* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2018 */
+/* Copyright (c) University of Cambridge 1995 - 2019 */
+/* Copyright (c) The Exim Maintainers 2020 - 2021 */
/* See the file NOTICE for conditions of use and distribution. */
/* Portions Copyright (c) The OpenSSL Project 1999 */
#endif
#if OPENSSL_VERSION_NUMBER >= 0x10100000L
# define EXIM_HAVE_OCSP_RESP_COUNT
+# define OPENSSL_AUTO_SHA256
#else
# define EXIM_HAVE_EPHEM_RSA_KEX
# define EXIM_HAVE_RAND_PSEUDO
# define EXIM_HAVE_SHA256
#endif
-/*
- * X509_check_host provides sane certificate hostname checking, but was added
- * to OpenSSL late, after other projects forked off the code-base. So in
- * addition to guarding against the base version number, beware that LibreSSL
- * does not (at this time) support this function.
- *
- * If LibreSSL gains a different API, perhaps via libtls, then we'll probably
- * opt to disentangle and ask a LibreSSL user to provide glue for a third
- * crypto provider for libtls instead of continuing to tie the OpenSSL glue
- * into even twistier knots. If LibreSSL gains the same API, we can just
- * change this guard and punt the issue for a while longer.
- */
+/* X509_check_host provides sane certificate hostname checking, but was added
+to OpenSSL late, after other projects forked off the code-base. So in
+addition to guarding against the base version number, beware that LibreSSL
+does not (at this time) support this function.
+
+If LibreSSL gains a different API, perhaps via libtls, then we'll probably
+opt to disentangle and ask a LibreSSL user to provide glue for a third
+crypto provider for libtls instead of continuing to tie the OpenSSL glue
+into even twistier knots. If LibreSSL gains the same API, we can just
+change this guard and punt the issue for a while longer. */
+
#ifndef LIBRESSL_VERSION_NUMBER
# if OPENSSL_VERSION_NUMBER >= 0x010100000L
# define EXIM_HAVE_OPENSSL_CHECKHOST
# define EXIM_HAVE_OPENSSL_DH_BITS
# define EXIM_HAVE_OPENSSL_TLS_METHOD
+# define EXIM_HAVE_OPENSSL_KEYLOG
+# define EXIM_HAVE_OPENSSL_CIPHER_GET_ID
+# define EXIM_HAVE_SESSION_TICKET
+# define EXIM_HAVE_OPESSL_TRACE
+# define EXIM_HAVE_OPESSL_GET0_SERIAL
+# ifndef DISABLE_OCSP
+# define EXIM_HAVE_OCSP
+# endif
+# define EXIM_HAVE_ALPN /* fail ret from hshake-cb is ignored by LibreSSL */
# else
# define EXIM_NEED_OPENSSL_INIT
# endif
# endif
#endif
+#if LIBRESSL_VERSION_NUMBER >= 0x3040000fL
+# define EXIM_HAVE_OPENSSL_CIPHER_GET_ID
+#endif
+
#if !defined(LIBRESSL_VERSION_NUMBER) \
|| LIBRESSL_VERSION_NUMBER >= 0x20010000L
# if !defined(OPENSSL_NO_ECDH)
# endif
#endif
+#ifndef LIBRESSL_VERSION_NUMBER
+# if OPENSSL_VERSION_NUMBER >= 0x010101000L
+# define OPENSSL_HAVE_KEYLOG_CB
+# define OPENSSL_HAVE_NUM_TICKETS
+# define EXIM_HAVE_OPENSSL_CIPHER_STD_NAME
+# else
+# define OPENSSL_BAD_SRVR_OURCERT
+# endif
+#endif
+
#if !defined(EXIM_HAVE_OPENSSL_TLSEXT) && !defined(DISABLE_OCSP)
# warning "OpenSSL library version too old; define DISABLE_OCSP in Makefile"
# define DISABLE_OCSP
#endif
+#ifndef DISABLE_TLS_RESUME
+# if OPENSSL_VERSION_NUMBER < 0x0101010L
+# error OpenSSL version too old for session-resumption
+# endif
+#endif
+
#ifdef EXIM_HAVE_OPENSSL_CHECKHOST
# include <openssl/x509v3.h>
#endif
+#ifndef EXIM_HAVE_OPENSSL_CIPHER_STD_NAME
+# ifndef EXIM_HAVE_OPENSSL_CIPHER_GET_ID
+# define SSL_CIPHER_get_id(c) (c->id)
+# endif
+# ifndef MACRO_PREDEF
+# include "tls-cipher-stdname.c"
+# endif
+#endif
+
/*************************************************
* OpenSSL option parse *
*************************************************/
to apply.
This list is current as of:
- ==> 1.0.1b <==
-Plus SSL_OP_SAFARI_ECDHE_ECDSA_BUG from 2013-June patch/discussion on openssl-dev
-Plus SSL_OP_NO_TLSv1_3 for 1.1.2-dev
+ ==> 1.1.1c <==
+
+XXX could we autobuild this list, as with predefined-macros?
+Seems just parsing ssl.h for SSL_OP_.* would be enough (except to exclude DTLS).
+Also allow a numeric literal?
*/
static exim_openssl_option exim_openssl_options[] = {
/* KEEP SORTED ALPHABETICALLY! */
#ifdef SSL_OP_ALL
- { US"all", SSL_OP_ALL },
+ { US"all", (long) SSL_OP_ALL },
+#endif
+#ifdef SSL_OP_ALLOW_NO_DHE_KEX
+ { US"allow_no_dhe_kex", SSL_OP_ALLOW_NO_DHE_KEX },
#endif
#ifdef SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
{ US"allow_unsafe_legacy_renegotiation", SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION },
#ifdef SSL_OP_CIPHER_SERVER_PREFERENCE
{ US"cipher_server_preference", SSL_OP_CIPHER_SERVER_PREFERENCE },
#endif
+#ifdef SSL_OP_CRYPTOPRO_TLSEXT_BUG
+ { US"cryptopro_tlsext_bug", SSL_OP_CRYPTOPRO_TLSEXT_BUG },
+#endif
#ifdef SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS
{ US"dont_insert_empty_fragments", SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS },
#endif
+#ifdef SSL_OP_ENABLE_MIDDLEBOX_COMPAT
+ { US"enable_middlebox_compat", SSL_OP_ENABLE_MIDDLEBOX_COMPAT },
+#endif
#ifdef SSL_OP_EPHEMERAL_RSA
{ US"ephemeral_rsa", SSL_OP_EPHEMERAL_RSA },
#endif
#ifdef SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG
{ US"netscape_reuse_cipher_change_bug", SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG },
#endif
+#ifdef SSL_OP_NO_ANTI_REPLAY
+ { US"no_anti_replay", SSL_OP_NO_ANTI_REPLAY },
+#endif
#ifdef SSL_OP_NO_COMPRESSION
{ US"no_compression", SSL_OP_NO_COMPRESSION },
#endif
+#ifdef SSL_OP_NO_ENCRYPT_THEN_MAC
+ { US"no_encrypt_then_mac", SSL_OP_NO_ENCRYPT_THEN_MAC },
+#endif
+#ifdef SSL_OP_NO_RENEGOTIATION
+ { US"no_renegotiation", SSL_OP_NO_RENEGOTIATION },
+#endif
#ifdef SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
{ US"no_session_resumption_on_renegotiation", SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION },
#endif
{ US"no_tlsv1", SSL_OP_NO_TLSv1 },
#endif
#ifdef SSL_OP_NO_TLSv1_1
-#if SSL_OP_NO_TLSv1_1 == 0x00000400L
+# if SSL_OP_NO_TLSv1_1 == 0x00000400L
/* Error in chosen value in 1.0.1a; see first item in CHANGES for 1.0.1b */
-#warning OpenSSL 1.0.1a uses a bad value for SSL_OP_NO_TLSv1_1, ignoring
-#else
+# warning OpenSSL 1.0.1a uses a bad value for SSL_OP_NO_TLSv1_1, ignoring
+# else
{ US"no_tlsv1_1", SSL_OP_NO_TLSv1_1 },
-#endif
+# endif
#endif
#ifdef SSL_OP_NO_TLSv1_2
{ US"no_tlsv1_2", SSL_OP_NO_TLSv1_2 },
#ifdef SSL_OP_NO_TLSv1_3
{ US"no_tlsv1_3", SSL_OP_NO_TLSv1_3 },
#endif
+#ifdef SSL_OP_PRIORITIZE_CHACHA
+ { US"prioritize_chacha", SSL_OP_PRIORITIZE_CHACHA },
+#endif
#ifdef SSL_OP_SAFARI_ECDHE_ECDSA_BUG
{ US"safari_ecdhe_ecdsa_bug", SSL_OP_SAFARI_ECDHE_ECDSA_BUG },
#endif
#ifdef SSL_OP_TLS_ROLLBACK_BUG
{ US"tls_rollback_bug", SSL_OP_TLS_ROLLBACK_BUG },
#endif
+#ifdef SSL_OP_TLSEXT_PADDING
+ { US"tlsext_padding", SSL_OP_TLSEXT_PADDING },
+#endif
};
#ifndef MACRO_PREDEF
static int exim_openssl_options_size = nelem(exim_openssl_options);
+static long init_options = 0;
#endif
#ifdef MACRO_PREDEF
void
options_tls(void)
{
-struct exim_openssl_option * o;
uschar buf[64];
-for (o = exim_openssl_options;
+for (struct exim_openssl_option * o = exim_openssl_options;
o < exim_openssl_options + nelem(exim_openssl_options); o++)
{
/* Trailing X is workaround for problem with _OPT_OPENSSL_NO_TLSV1
spf(buf, sizeof(buf), US"_OPT_OPENSSL_%T_X", o->name);
builtin_macro_create(buf);
}
+
+# ifndef DISABLE_TLS_RESUME
+builtin_macro_create_var(US"_RESUME_DECODE", RESUME_DECODE_STRING );
+# endif
+# ifdef SSL_OP_NO_TLSv1_3
+builtin_macro_create(US"_HAVE_TLS1_3");
+# endif
+# ifdef OPENSSL_BAD_SRVR_OURCERT
+builtin_macro_create(US"_TLS_BAD_MULTICERT_IN_OURCERT");
+# endif
+# ifdef EXIM_HAVE_OCSP
+builtin_macro_create(US"_HAVE_TLS_OCSP");
+builtin_macro_create(US"_HAVE_TLS_OCSP_LIST");
+# endif
+# ifdef EXIM_HAVE_ALPN
+builtin_macro_create(US"_HAVE_TLS_ALPN");
+# endif
}
#else
typedef struct {
SSL_CTX * ctx;
SSL * ssl;
+ gstring * corked;
} exim_openssl_client_tls_ctx;
-static SSL_CTX *server_ctx = NULL;
-static SSL *server_ssl = NULL;
+
+/* static SSL_CTX *server_ctx = NULL; */
+/* static SSL *server_ssl = NULL; */
#ifdef EXIM_HAVE_OPENSSL_TLSEXT
static SSL_CTX *server_sni = NULL;
#endif
+#ifdef EXIM_HAVE_ALPN
+static BOOL server_seen_alpn = FALSE;
+#endif
static char ssl_errstring[256];
-static int ssl_session_timeout = 200;
+static int ssl_session_timeout = 7200; /* Two hours */
static BOOL client_verify_optional = FALSE;
static BOOL server_verify_optional = FALSE;
static BOOL reexpand_tls_files_for_sni = FALSE;
-typedef struct tls_ext_ctx_cb {
- uschar *certificate;
- uschar *privatekey;
- BOOL is_server;
+typedef struct ocsp_resp {
+ struct ocsp_resp * next;
+ OCSP_RESPONSE * resp;
+} ocsp_resplist;
+
+typedef struct exim_openssl_state {
+ exim_tlslib_state lib_state;
+#define lib_ctx libdata0
+#define lib_ssl libdata1
+
+ tls_support * tlsp;
+ uschar * certificate;
+ uschar * privatekey;
+ BOOL is_server;
#ifndef DISABLE_OCSP
STACK_OF(X509) *verify_stack; /* chain for verifying the proof */
union {
struct {
uschar *file;
- uschar *file_expanded;
- OCSP_RESPONSE *response;
+ const uschar *file_expanded;
+ ocsp_resplist *olist;
} server;
struct {
X509_STORE *verify_store; /* non-null if status requested */
} client;
} u_ocsp;
#endif
- uschar *dhparam;
+ uschar * dhparam;
/* these are cached from first expand */
- uschar *server_cipher_list;
+ uschar * server_cipher_list;
/* only passed down to tls_error: */
- host_item *host;
+ host_item * host;
const uschar * verify_cert_hostnames;
#ifndef DISABLE_EVENT
- uschar * event_action;
+ uschar * event_action;
#endif
-} tls_ext_ctx_cb;
+} exim_openssl_state_st;
/* should figure out a cleanup of API to handle state preserved per
implementation, for various reasons, which can be void * in the APIs.
For now, we hack around it. */
-tls_ext_ctx_cb *client_static_cbinfo = NULL;
-tls_ext_ctx_cb *server_static_cbinfo = NULL;
+exim_openssl_state_st *client_static_state = NULL; /*XXX should not use static; multiple concurrent clients! */
+exim_openssl_state_st state_server = {.is_server = TRUE};
static int
-setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host, BOOL optional,
- int (*cert_vfy_cb)(int, X509_STORE_CTX *), uschar ** errstr );
+setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host,
+ uschar ** errstr );
/* Callbacks */
-#ifdef EXIM_HAVE_OPENSSL_TLSEXT
-static int tls_servername_cb(SSL *s, int *ad ARG_UNUSED, void *arg);
-#endif
#ifndef DISABLE_OCSP
static int tls_server_stapling_cb(SSL *s, void *arg);
#endif
+
+/* Daemon-called, before every connection, key create/rotate */
+#ifndef DISABLE_TLS_RESUME
+static void tk_init(void);
+static int tls_exdata_idx = -1;
+#endif
+
+static void
+tls_per_lib_daemon_tick(void)
+{
+#ifndef DISABLE_TLS_RESUME
+tk_init();
+#endif
+}
+
+/* Called once at daemon startup */
+
+static void
+tls_per_lib_daemon_init(void)
+{
+tls_daemon_creds_reload();
+}
+
+
/*************************************************
* Handle TLS error *
*************************************************/
-/*************************************************
-* Callback to generate RSA key *
-*************************************************/
-
-/*
-Arguments:
- s SSL connection (not used)
- export not used
- keylength keylength
-
-Returns: pointer to generated key
-*/
+/**************************************************
+* General library initalisation *
+**************************************************/
-static RSA *
-rsa_callback(SSL *s, int export, int keylength)
+static BOOL
+lib_rand_init(void * addr)
{
-RSA *rsa_key;
-#ifdef EXIM_HAVE_RSA_GENKEY_EX
-BIGNUM *bn = BN_new();
-#endif
-
-export = export; /* Shut picky compilers up */
-DEBUG(D_tls) debug_printf("Generating %d bit RSA key...\n", keylength);
+randstuff r;
+if (!RAND_status()) return TRUE;
-#ifdef EXIM_HAVE_RSA_GENKEY_EX
-if ( !BN_set_word(bn, (unsigned long)RSA_F4)
- || !(rsa_key = RSA_new())
- || !RSA_generate_key_ex(rsa_key, keylength, bn, NULL)
- )
-#else
-if (!(rsa_key = RSA_generate_key(keylength, RSA_F4, NULL, NULL)))
-#endif
+gettimeofday(&r.tv, NULL);
+r.p = getpid();
+RAND_seed(US (&r), sizeof(r));
+RAND_seed(US big_buffer, big_buffer_size);
+if (addr) RAND_seed(US addr, sizeof(addr));
- {
- ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
- log_write(0, LOG_MAIN|LOG_PANIC, "TLS error (RSA_generate_key): %s",
- ssl_errstring);
- return NULL;
- }
-return rsa_key;
+return RAND_status();
}
-
-/* Extreme debug
-#ifndef DISABLE_OCSP
-void
-x509_store_dump_cert_s_names(X509_STORE * store)
+static void
+tls_openssl_init(void)
{
-STACK_OF(X509_OBJECT) * roots= store->objs;
-int i;
-static uschar name[256];
+static BOOL once = FALSE;
+if (once) return;
+once = TRUE;
-for(i= 0; i<sk_X509_OBJECT_num(roots); i++)
- {
- X509_OBJECT * tmp_obj= sk_X509_OBJECT_value(roots, i);
- if(tmp_obj->type == X509_LU_X509)
- {
- X509_NAME * sn = X509_get_subject_name(tmp_obj->data.x509);
- if (X509_NAME_oneline(sn, CS name, sizeof(name)))
- {
- name[sizeof(name)-1] = '\0';
- debug_printf(" %s\n", name);
- }
- }
- }
-}
+#ifdef EXIM_NEED_OPENSSL_INIT
+SSL_load_error_strings(); /* basic set up */
+OpenSSL_add_ssl_algorithms();
#endif
-*/
-
-
-#ifndef DISABLE_EVENT
-static int
-verify_event(tls_support * tlsp, X509 * cert, int depth, const uschar * dn,
- BOOL *calledp, const BOOL *optionalp, const uschar * what)
-{
-uschar * ev;
-uschar * yield;
-X509 * old_cert;
-ev = tlsp == &tls_out ? client_static_cbinfo->event_action : event_action;
-if (ev)
- {
- DEBUG(D_tls) debug_printf("verify_event: %s %d\n", what, depth);
- old_cert = tlsp->peercert;
- tlsp->peercert = X509_dup(cert);
- /* NB we do not bother setting peerdn */
- if ((yield = event_raise(ev, US"tls:cert", string_sprintf("%d", depth))))
- {
- log_write(0, LOG_MAIN, "[%s] %s verify denied by event-action: "
- "depth=%d cert=%s: %s",
- tlsp == &tls_out ? deliver_host_address : sender_host_address,
- what, depth, dn, yield);
- *calledp = TRUE;
- if (!*optionalp)
- {
- if (old_cert) tlsp->peercert = old_cert; /* restore 1st failing cert */
- return 1; /* reject (leaving peercert set) */
- }
- DEBUG(D_tls) debug_printf("Event-action verify failure overridden "
- "(host in tls_try_verify_hosts)\n");
- }
- X509_free(tlsp->peercert);
- tlsp->peercert = old_cert;
- }
-return 0;
-}
+#if defined(EXIM_HAVE_SHA256) && !defined(OPENSSL_AUTO_SHA256)
+/* SHA256 is becoming ever more popular. This makes sure it gets added to the
+list of available digests. */
+EVP_add_digest(EVP_sha256());
#endif
-/*************************************************
-* Callback for verification *
-*************************************************/
+(void) lib_rand_init(NULL);
+(void) tls_openssl_options_parse(openssl_options, &init_options);
+}
-/* The SSL library does certificate verification if set up to do so. This
-callback has the current yes/no state is in "state". If verification succeeded,
-we set the certificate-verified flag. If verification failed, what happens
-depends on whether the client is required to present a verifiable certificate
-or not.
-If verification is optional, we change the state to yes, but still log the
-verification error. For some reason (it really would help to have proper
-documentation of OpenSSL), this callback function then gets called again, this
-time with state = 1. We must take care not to set the private verified flag on
-the second time through.
-Note: this function is not called if the client fails to present a certificate
-when asked. We get here only if a certificate has been received. Handling of
-optional verification for this case is done when requesting SSL to verify, by
-setting SSL_VERIFY_FAIL_IF_NO_PEER_CERT in the non-optional case.
+/*************************************************
+* Initialize for DH *
+*************************************************/
-May be called multiple times for different issues with a certificate, even
-for a given "depth" in the certificate chain.
+/* If dhparam is set, expand it, and load up the parameters for DH encryption.
Arguments:
- preverify_ok current yes/no state as 1/0
- x509ctx certificate information.
- tlsp per-direction (client vs. server) support data
- calledp has-been-called flag
- optionalp verification-is-optional flag
+ sctx The current SSL CTX (inbound or outbound)
+ dhparam DH parameter file or fixed parameter identity string
+ host connected host, if client; NULL if server
+ errstr error string pointer
-Returns: 0 if verification should fail, otherwise 1
+Returns: TRUE if OK (nothing to set up, or setup worked)
*/
-static int
-verify_callback(int preverify_ok, X509_STORE_CTX * x509ctx,
- tls_support * tlsp, BOOL * calledp, BOOL * optionalp)
+static BOOL
+init_dh(SSL_CTX *sctx, uschar *dhparam, const host_item *host, uschar ** errstr)
{
-X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx);
-int depth = X509_STORE_CTX_get_error_depth(x509ctx);
-uschar dn[256];
+BIO *bio;
+DH *dh;
+uschar *dhexpanded;
+const char *pem;
+int dh_bitsize;
-if (!X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)))
+if (!expand_check(dhparam, US"tls_dhparam", &dhexpanded, errstr))
+ return FALSE;
+
+if (!dhexpanded || !*dhexpanded)
+ bio = BIO_new_mem_buf(CS std_dh_prime_default(), -1);
+else if (dhexpanded[0] == '/')
{
- DEBUG(D_tls) debug_printf("X509_NAME_oneline() error\n");
- log_write(0, LOG_MAIN, "[%s] SSL verify error: internal error",
- tlsp == &tls_out ? deliver_host_address : sender_host_address);
- return 0;
+ if (!(bio = BIO_new_file(CS dhexpanded, "r")))
+ {
+ tls_error(string_sprintf("could not read dhparams file %s", dhexpanded),
+ host, US strerror(errno), errstr);
+ return FALSE;
+ }
}
-dn[sizeof(dn)-1] = '\0';
-
-if (preverify_ok == 0)
+else
{
- uschar * extra = verify_mode ? string_sprintf(" (during %c-verify for [%s])",
- *verify_mode, sender_host_address)
- : US"";
- log_write(0, LOG_MAIN, "[%s] SSL verify error%s: depth=%d error=%s cert=%s",
- tlsp == &tls_out ? deliver_host_address : sender_host_address,
- extra, depth,
- X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)), dn);
- *calledp = TRUE;
- if (!*optionalp)
+ if (Ustrcmp(dhexpanded, "none") == 0)
{
- if (!tlsp->peercert)
- tlsp->peercert = X509_dup(cert); /* record failing cert */
- return 0; /* reject */
+ DEBUG(D_tls) debug_printf("Requested no DH parameters.\n");
+ return TRUE;
}
- DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in "
- "tls_try_verify_hosts)\n");
+
+ if (!(pem = std_dh_prime_named(dhexpanded)))
+ {
+ tls_error(string_sprintf("Unknown standard DH prime \"%s\"", dhexpanded),
+ host, US strerror(errno), errstr);
+ return FALSE;
+ }
+ bio = BIO_new_mem_buf(CS pem, -1);
}
-else if (depth != 0)
+if (!(dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL)))
{
- DEBUG(D_tls) debug_printf("SSL verify ok: depth=%d SN=%s\n", depth, dn);
+ BIO_free(bio);
+ tls_error(string_sprintf("Could not read tls_dhparams \"%s\"", dhexpanded),
+ host, NULL, errstr);
+ return FALSE;
+ }
+
+/* note: our default limit of 2236 is not a multiple of 8; the limit comes from
+ * an NSS limit, and the GnuTLS APIs handle bit-sizes fine, so we went with
+ * 2236. But older OpenSSL can only report in bytes (octets), not bits.
+ * If someone wants to dance at the edge, then they can raise the limit or use
+ * current libraries. */
+#ifdef EXIM_HAVE_OPENSSL_DH_BITS
+/* Added in commit 26c79d5641d; `git describe --contains` says OpenSSL_1_1_0-pre1~1022
+ * This predates OpenSSL_1_1_0 (before a, b, ...) so is in all 1.1.0 */
+dh_bitsize = DH_bits(dh);
+#else
+dh_bitsize = 8 * DH_size(dh);
+#endif
+
+/* Even if it is larger, we silently return success rather than cause things
+ * to fail out, so that a too-large DH will not knock out all TLS; it's a
+ * debatable choice. */
+if (dh_bitsize > tls_dh_max_bits)
+ {
+ DEBUG(D_tls)
+ debug_printf("dhparams file %d bits, is > tls_dh_max_bits limit of %d\n",
+ dh_bitsize, tls_dh_max_bits);
+ }
+else
+ {
+ SSL_CTX_set_tmp_dh(sctx, dh);
+ DEBUG(D_tls)
+ debug_printf("Diffie-Hellman initialized from %s with %d-bit prime\n",
+ dhexpanded ? dhexpanded : US"default", dh_bitsize);
+ }
+
+DH_free(dh);
+BIO_free(bio);
+
+return TRUE;
+}
+
+
+
+
+/*************************************************
+* Initialize for ECDH *
+*************************************************/
+
+/* Load parameters for ECDH encryption.
+
+For now, we stick to NIST P-256 because: it's simple and easy to configure;
+it avoids any patent issues that might bite redistributors; despite events in
+the news and concerns over curve choices, we're not cryptographers, we're not
+pretending to be, and this is "good enough" to be better than no support,
+protecting against most adversaries. Given another year or two, there might
+be sufficient clarity about a "right" way forward to let us make an informed
+decision, instead of a knee-jerk reaction.
+
+Longer-term, we should look at supporting both various named curves and
+external files generated with "openssl ecparam", much as we do for init_dh().
+We should also support "none" as a value, to explicitly avoid initialisation.
+
+Patches welcome.
+
+Arguments:
+ sctx The current SSL CTX (inbound or outbound)
+ host connected host, if client; NULL if server
+ errstr error string pointer
+
+Returns: TRUE if OK (nothing to set up, or setup worked)
+*/
+
+static BOOL
+init_ecdh(SSL_CTX * sctx, host_item * host, uschar ** errstr)
+{
+#ifdef OPENSSL_NO_ECDH
+return TRUE;
+#else
+
+EC_KEY * ecdh;
+uschar * exp_curve;
+int nid;
+BOOL rv;
+
+if (host) /* No ECDH setup for clients, only for servers */
+ return TRUE;
+
+# ifndef EXIM_HAVE_ECDH
+DEBUG(D_tls)
+ debug_printf("No OpenSSL API to define ECDH parameters, skipping\n");
+return TRUE;
+# else
+
+if (!expand_check(tls_eccurve, US"tls_eccurve", &exp_curve, errstr))
+ return FALSE;
+if (!exp_curve || !*exp_curve)
+ return TRUE;
+
+/* "auto" needs to be handled carefully.
+ * OpenSSL < 1.0.2: we do not select anything, but fallback to prime256v1
+ * OpenSSL < 1.1.0: we have to call SSL_CTX_set_ecdh_auto
+ * (openssl/ssl.h defines SSL_CTRL_SET_ECDH_AUTO)
+ * OpenSSL >= 1.1.0: we do not set anything, the libray does autoselection
+ * https://github.com/openssl/openssl/commit/fe6ef2472db933f01b59cad82aa925736935984b
+ */
+if (Ustrcmp(exp_curve, "auto") == 0)
+ {
+#if OPENSSL_VERSION_NUMBER < 0x10002000L
+ DEBUG(D_tls) debug_printf(
+ "ECDH OpenSSL < 1.0.2: temp key parameter settings: overriding \"auto\" with \"prime256v1\"\n");
+ exp_curve = US"prime256v1";
+#else
+# if defined SSL_CTRL_SET_ECDH_AUTO
+ DEBUG(D_tls) debug_printf(
+ "ECDH OpenSSL 1.0.2+: temp key parameter settings: autoselection\n");
+ SSL_CTX_set_ecdh_auto(sctx, 1);
+ return TRUE;
+# else
+ DEBUG(D_tls) debug_printf(
+ "ECDH OpenSSL 1.1.0+: temp key parameter settings: default selection\n");
+ return TRUE;
+# endif
+#endif
+ }
+
+DEBUG(D_tls) debug_printf("ECDH: curve '%s'\n", exp_curve);
+if ( (nid = OBJ_sn2nid (CCS exp_curve)) == NID_undef
+# ifdef EXIM_HAVE_OPENSSL_EC_NIST2NID
+ && (nid = EC_curve_nist2nid(CCS exp_curve)) == NID_undef
+# endif
+ )
+ {
+ tls_error(string_sprintf("Unknown curve name tls_eccurve '%s'", exp_curve),
+ host, NULL, errstr);
+ return FALSE;
+ }
+
+if (!(ecdh = EC_KEY_new_by_curve_name(nid)))
+ {
+ tls_error(US"Unable to create ec curve", host, NULL, errstr);
+ return FALSE;
+ }
+
+/* The "tmp" in the name here refers to setting a temporary key
+not to the stability of the interface. */
+
+if ((rv = SSL_CTX_set_tmp_ecdh(sctx, ecdh) == 0))
+ tls_error(string_sprintf("Error enabling '%s' curve", exp_curve), host, NULL, errstr);
+else
+ DEBUG(D_tls) debug_printf("ECDH: enabled '%s' curve\n", exp_curve);
+
+EC_KEY_free(ecdh);
+return !rv;
+
+# endif /*EXIM_HAVE_ECDH*/
+#endif /*OPENSSL_NO_ECDH*/
+}
+
+
+
+/*************************************************
+* Expand key and cert file specs *
+*************************************************/
+
+/*
+Arguments:
+ s SSL connection (not used)
+ export not used
+ keylength keylength
+
+Returns: pointer to generated key
+*/
+
+static RSA *
+rsa_callback(SSL *s, int export, int keylength)
+{
+RSA *rsa_key;
+#ifdef EXIM_HAVE_RSA_GENKEY_EX
+BIGNUM *bn = BN_new();
+#endif
+
+DEBUG(D_tls) debug_printf("Generating %d bit RSA key...\n", keylength);
+
+#ifdef EXIM_HAVE_RSA_GENKEY_EX
+if ( !BN_set_word(bn, (unsigned long)RSA_F4)
+ || !(rsa_key = RSA_new())
+ || !RSA_generate_key_ex(rsa_key, keylength, bn, NULL)
+ )
+#else
+if (!(rsa_key = RSA_generate_key(keylength, RSA_F4, NULL, NULL)))
+#endif
+
+ {
+ ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
+ log_write(0, LOG_MAIN|LOG_PANIC, "TLS error (RSA_generate_key): %s",
+ ssl_errstring);
+ return NULL;
+ }
+return rsa_key;
+}
+
+
+
+/* Create and install a selfsigned certificate, for use in server mode */
+/*XXX we could arrange to call this during prelo for a null tls_certificate option.
+The normal cache inval + relo will suffice.
+Just need a timer for inval. */
+
+static int
+tls_install_selfsign(SSL_CTX * sctx, uschar ** errstr)
+{
+X509 * x509 = NULL;
+EVP_PKEY * pkey;
+RSA * rsa;
+X509_NAME * name;
+uschar * where;
+
+DEBUG(D_tls) debug_printf("TLS: generating selfsigned server cert\n");
+where = US"allocating pkey";
+if (!(pkey = EVP_PKEY_new()))
+ goto err;
+
+where = US"allocating cert";
+if (!(x509 = X509_new()))
+ goto err;
+
+where = US"generating pkey";
+if (!(rsa = rsa_callback(NULL, 0, 2048)))
+ goto err;
+
+where = US"assigning pkey";
+if (!EVP_PKEY_assign_RSA(pkey, rsa))
+ goto err;
+
+X509_set_version(x509, 2); /* N+1 - version 3 */
+ASN1_INTEGER_set(X509_get_serialNumber(x509), 1);
+X509_gmtime_adj(X509_get_notBefore(x509), 0);
+X509_gmtime_adj(X509_get_notAfter(x509), (long)2 * 60 * 60); /* 2 hour */
+X509_set_pubkey(x509, pkey);
+
+name = X509_get_subject_name(x509);
+X509_NAME_add_entry_by_txt(name, "C",
+ MBSTRING_ASC, CUS "UK", -1, -1, 0);
+X509_NAME_add_entry_by_txt(name, "O",
+ MBSTRING_ASC, CUS "Exim Developers", -1, -1, 0);
+X509_NAME_add_entry_by_txt(name, "CN",
+ MBSTRING_ASC, CUS smtp_active_hostname, -1, -1, 0);
+X509_set_issuer_name(x509, name);
+
+where = US"signing cert";
+if (!X509_sign(x509, pkey, EVP_md5()))
+ goto err;
+
+where = US"installing selfsign cert";
+if (!SSL_CTX_use_certificate(sctx, x509))
+ goto err;
+
+where = US"installing selfsign key";
+if (!SSL_CTX_use_PrivateKey(sctx, pkey))
+ goto err;
+
+return OK;
+
+err:
+ (void) tls_error(where, NULL, NULL, errstr);
+ if (x509) X509_free(x509);
+ if (pkey) EVP_PKEY_free(pkey);
+ return DEFER;
+}
+
+
+
+
+
+
+
+/*************************************************
+* Information callback *
+*************************************************/
+
+/* The SSL library functions call this from time to time to indicate what they
+are doing. We copy the string to the debugging output when TLS debugging has
+been requested.
+
+Arguments:
+ s the SSL connection
+ where
+ ret
+
+Returns: nothing
+*/
+
+static void
+info_callback(SSL *s, int where, int ret)
+{
+DEBUG(D_tls)
+ {
+ const uschar * str;
+
+ if (where & SSL_ST_CONNECT)
+ str = US"SSL_connect";
+ else if (where & SSL_ST_ACCEPT)
+ str = US"SSL_accept";
+ else
+ str = US"SSL info (undefined)";
+
+ if (where & SSL_CB_LOOP)
+ debug_printf("%s: %s\n", str, SSL_state_string_long(s));
+ else if (where & SSL_CB_ALERT)
+ debug_printf("SSL3 alert %s:%s:%s\n",
+ str = where & SSL_CB_READ ? US"read" : US"write",
+ SSL_alert_type_string_long(ret), SSL_alert_desc_string_long(ret));
+ else if (where & SSL_CB_EXIT)
+ {
+ if (ret == 0)
+ debug_printf("%s: failed in %s\n", str, SSL_state_string_long(s));
+ else if (ret < 0)
+ debug_printf("%s: error in %s\n", str, SSL_state_string_long(s));
+ }
+ else if (where & SSL_CB_HANDSHAKE_START)
+ debug_printf("%s: hshake start: %s\n", str, SSL_state_string_long(s));
+ else if (where & SSL_CB_HANDSHAKE_DONE)
+ debug_printf("%s: hshake done: %s\n", str, SSL_state_string_long(s));
+ }
+}
+
+#ifdef OPENSSL_HAVE_KEYLOG_CB
+static void
+keylog_callback(const SSL *ssl, const char *line)
+{
+char * filename;
+FILE * fp;
+DEBUG(D_tls) debug_printf("%.200s\n", line);
+if (!(filename = getenv("SSLKEYLOGFILE"))) return;
+if (!(fp = fopen(filename, "a"))) return;
+fprintf(fp, "%s\n", line);
+fclose(fp);
+}
+#endif
+
+
+
+
+
+#ifndef DISABLE_EVENT
+static int
+verify_event(tls_support * tlsp, X509 * cert, int depth, const uschar * dn,
+ BOOL *calledp, const BOOL *optionalp, const uschar * what)
+{
+uschar * ev;
+uschar * yield;
+X509 * old_cert;
+
+ev = tlsp == &tls_out ? client_static_state->event_action : event_action;
+if (ev)
+ {
+ DEBUG(D_tls) debug_printf("verify_event: %s %d\n", what, depth);
+ old_cert = tlsp->peercert;
+ tlsp->peercert = X509_dup(cert);
+ /* NB we do not bother setting peerdn */
+ if ((yield = event_raise(ev, US"tls:cert", string_sprintf("%d", depth))))
+ {
+ log_write(0, LOG_MAIN, "[%s] %s verify denied by event-action: "
+ "depth=%d cert=%s: %s",
+ tlsp == &tls_out ? deliver_host_address : sender_host_address,
+ what, depth, dn, yield);
+ *calledp = TRUE;
+ if (!*optionalp)
+ {
+ if (old_cert) tlsp->peercert = old_cert; /* restore 1st failing cert */
+ return 1; /* reject (leaving peercert set) */
+ }
+ DEBUG(D_tls) debug_printf("Event-action verify failure overridden "
+ "(host in tls_try_verify_hosts)\n");
+ tlsp->verify_override = TRUE;
+ }
+ X509_free(tlsp->peercert);
+ tlsp->peercert = old_cert;
+ }
+return 0;
+}
+#endif
+
+/*************************************************
+* Callback for verification *
+*************************************************/
+
+/* The SSL library does certificate verification if set up to do so. This
+callback has the current yes/no state is in "state". If verification succeeded,
+we set the certificate-verified flag. If verification failed, what happens
+depends on whether the client is required to present a verifiable certificate
+or not.
+
+If verification is optional, we change the state to yes, but still log the
+verification error. For some reason (it really would help to have proper
+documentation of OpenSSL), this callback function then gets called again, this
+time with state = 1. We must take care not to set the private verified flag on
+the second time through.
+
+Note: this function is not called if the client fails to present a certificate
+when asked. We get here only if a certificate has been received. Handling of
+optional verification for this case is done when requesting SSL to verify, by
+setting SSL_VERIFY_FAIL_IF_NO_PEER_CERT in the non-optional case.
+
+May be called multiple times for different issues with a certificate, even
+for a given "depth" in the certificate chain.
+
+Arguments:
+ preverify_ok current yes/no state as 1/0
+ x509ctx certificate information.
+ tlsp per-direction (client vs. server) support data
+ calledp has-been-called flag
+ optionalp verification-is-optional flag
+
+Returns: 0 if verification should fail, otherwise 1
+*/
+
+static int
+verify_callback(int preverify_ok, X509_STORE_CTX * x509ctx,
+ tls_support * tlsp, BOOL * calledp, BOOL * optionalp)
+{
+X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx);
+int depth = X509_STORE_CTX_get_error_depth(x509ctx);
+uschar dn[256];
+
+if (!X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)))
+ {
+ DEBUG(D_tls) debug_printf("X509_NAME_oneline() error\n");
+ log_write(0, LOG_MAIN, "[%s] SSL verify error: internal error",
+ tlsp == &tls_out ? deliver_host_address : sender_host_address);
+ return 0;
+ }
+dn[sizeof(dn)-1] = '\0';
+
+tlsp->verify_override = FALSE;
+if (preverify_ok == 0)
+ {
+ uschar * extra = verify_mode ? string_sprintf(" (during %c-verify for [%s])",
+ *verify_mode, sender_host_address)
+ : US"";
+ log_write(0, LOG_MAIN, "[%s] SSL verify error%s: depth=%d error=%s cert=%s",
+ tlsp == &tls_out ? deliver_host_address : sender_host_address,
+ extra, depth,
+ X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)), dn);
+ *calledp = TRUE;
+ if (!*optionalp)
+ {
+ if (!tlsp->peercert)
+ tlsp->peercert = X509_dup(cert); /* record failing cert */
+ return 0; /* reject */
+ }
+ DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in "
+ "tls_try_verify_hosts)\n");
+ tlsp->verify_override = TRUE;
+ }
+
+else if (depth != 0)
+ {
+ DEBUG(D_tls) debug_printf("SSL verify ok: depth=%d SN=%s\n", depth, dn);
#ifndef DISABLE_OCSP
- if (tlsp == &tls_out && client_static_cbinfo->u_ocsp.client.verify_store)
+ if (tlsp == &tls_out && client_static_state->u_ocsp.client.verify_store)
{ /* client, wanting stapling */
/* Add the server cert's signing chain as the one
for the verification of the OCSP stapled information. */
- if (!X509_STORE_add_cert(client_static_cbinfo->u_ocsp.client.verify_store,
+ if (!X509_STORE_add_cert(client_static_state->u_ocsp.client.verify_store,
cert))
ERR_clear_error();
- sk_X509_push(client_static_cbinfo->verify_stack, cert);
+ sk_X509_push(client_static_state->verify_stack, cert);
}
#endif
#ifndef DISABLE_EVENT
const uschar * verify_cert_hostnames;
if ( tlsp == &tls_out
- && ((verify_cert_hostnames = client_static_cbinfo->verify_cert_hostnames)))
+ && ((verify_cert_hostnames = client_static_state->verify_cert_hostnames)))
/* client, wanting hostname check */
{
tlsp->peercert = X509_dup(cert); /* record failing cert */
return 0; /* reject */
}
- DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in "
+ DEBUG(D_tls) debug_printf("SSL verify name failure overridden (host in "
"tls_try_verify_hosts)\n");
+ tlsp->verify_override = TRUE;
}
}
DEBUG(D_tls) debug_printf("SSL%s verify ok: depth=0 SN=%s\n",
*calledp ? "" : " authenticated", dn);
- if (!*calledp) tlsp->certificate_verified = TRUE;
*calledp = TRUE;
}
&client_verify_callback_called, &client_verify_optional);
}
-static int
-verify_callback_server(int preverify_ok, X509_STORE_CTX *x509ctx)
-{
-return verify_callback(preverify_ok, x509ctx, &tls_in,
- &server_verify_callback_called, &server_verify_optional);
-}
+static int
+verify_callback_server(int preverify_ok, X509_STORE_CTX *x509ctx)
+{
+return verify_callback(preverify_ok, x509ctx, &tls_in,
+ &server_verify_callback_called, &server_verify_optional);
+}
+
+
+#ifdef SUPPORT_DANE
+
+/* This gets called *by* the dane library verify callback, which interposes
+itself.
+*/
+static int
+verify_callback_client_dane(int preverify_ok, X509_STORE_CTX * x509ctx)
+{
+X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx);
+uschar dn[256];
+int depth = X509_STORE_CTX_get_error_depth(x509ctx);
+#ifndef DISABLE_EVENT
+BOOL dummy_called, optional = FALSE;
+#endif
+
+if (!X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)))
+ {
+ DEBUG(D_tls) debug_printf("X509_NAME_oneline() error\n");
+ log_write(0, LOG_MAIN, "[%s] SSL verify error: internal error",
+ deliver_host_address);
+ return 0;
+ }
+dn[sizeof(dn)-1] = '\0';
+
+DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s depth %d %s\n",
+ preverify_ok ? "ok":"BAD", depth, dn);
+
+#ifndef DISABLE_EVENT
+ if (verify_event(&tls_out, cert, depth, dn,
+ &dummy_called, &optional, US"DANE"))
+ return 0; /* reject, with peercert set */
+#endif
+
+if (preverify_ok == 1)
+ {
+ tls_out.dane_verified = TRUE;
+#ifndef DISABLE_OCSP
+ if (client_static_state->u_ocsp.client.verify_store)
+ { /* client, wanting stapling */
+ /* Add the server cert's signing chain as the one
+ for the verification of the OCSP stapled information. */
+
+ if (!X509_STORE_add_cert(client_static_state->u_ocsp.client.verify_store,
+ cert))
+ ERR_clear_error();
+ sk_X509_push(client_static_state->verify_stack, cert);
+ }
+#endif
+ }
+else
+ {
+ int err = X509_STORE_CTX_get_error(x509ctx);
+ DEBUG(D_tls)
+ debug_printf(" - err %d '%s'\n", err, X509_verify_cert_error_string(err));
+ if (err == X509_V_ERR_APPLICATION_VERIFICATION)
+ preverify_ok = 1;
+ }
+return preverify_ok;
+}
+
+#endif /*SUPPORT_DANE*/
+
+
+#ifndef DISABLE_OCSP
+/*************************************************
+* Load OCSP information into state *
+*************************************************/
+/* Called to load the server OCSP response from the given file into memory, once
+caller has determined this is needed. Checks validity. Debugs a message
+if invalid.
+
+ASSUMES: single response, for single cert.
+
+Arguments:
+ state various parts of session state
+ filename the filename putatively holding an OCSP response
+ is_pem file is PEM format; otherwise is DER
+*/
+
+static void
+ocsp_load_response(exim_openssl_state_st * state, const uschar * filename,
+ BOOL is_pem)
+{
+BIO * bio;
+OCSP_RESPONSE * resp;
+OCSP_BASICRESP * basic_response;
+OCSP_SINGLERESP * single_response;
+ASN1_GENERALIZEDTIME * rev, * thisupd, * nextupd;
+STACK_OF(X509) * sk;
+unsigned long verify_flags;
+int status, reason, i;
+
+DEBUG(D_tls)
+ debug_printf("tls_ocsp_file (%s) '%s'\n", is_pem ? "PEM" : "DER", filename);
+
+if (!filename || !*filename) return;
+
+ERR_clear_error();
+if (!(bio = BIO_new_file(CS filename, "rb")))
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "Failed to open OCSP response file \"%s\": %.100s",
+ filename, ERR_reason_error_string(ERR_get_error()));
+ return;
+ }
+
+if (is_pem)
+ {
+ uschar * data, * freep;
+ char * dummy;
+ long len;
+ if (!PEM_read_bio(bio, &dummy, &dummy, &data, &len))
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "Failed to read PEM file \"%s\": %.100s",
+ filename, ERR_reason_error_string(ERR_get_error()));
+ return;
+ }
+ freep = data;
+ resp = d2i_OCSP_RESPONSE(NULL, CUSS &data, len);
+ OPENSSL_free(freep);
+ }
+else
+ resp = d2i_OCSP_RESPONSE_bio(bio, NULL);
+BIO_free(bio);
+
+if (!resp)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "Error reading OCSP response from \"%s\": %s",
+ filename, ERR_reason_error_string(ERR_get_error()));
+ return;
+ }
+
+if ((status = OCSP_response_status(resp)) != OCSP_RESPONSE_STATUS_SUCCESSFUL)
+ {
+ DEBUG(D_tls) debug_printf("OCSP response not valid: %s (%d)\n",
+ OCSP_response_status_str(status), status);
+ goto bad;
+ }
+
+#ifdef notdef
+ {
+ BIO * bp = BIO_new_fp(debug_file, BIO_NOCLOSE);
+ OCSP_RESPONSE_print(bp, resp, 0); /* extreme debug: stapling content */
+ BIO_free(bp);
+ }
+#endif
+
+if (!(basic_response = OCSP_response_get1_basic(resp)))
+ {
+ DEBUG(D_tls)
+ debug_printf("OCSP response parse error: unable to extract basic response.\n");
+ goto bad;
+ }
+
+sk = state->verify_stack;
+verify_flags = OCSP_NOVERIFY; /* check sigs, but not purpose */
+
+/* May need to expose ability to adjust those flags?
+OCSP_NOSIGS OCSP_NOVERIFY OCSP_NOCHAIN OCSP_NOCHECKS OCSP_NOEXPLICIT
+OCSP_TRUSTOTHER OCSP_NOINTERN */
+
+/* This does a full verify on the OCSP proof before we load it for serving
+up; possibly overkill - just date-checks might be nice enough.
+
+OCSP_basic_verify takes a "store" arg, but does not
+use it for the chain verification, which is all we do
+when OCSP_NOVERIFY is set. The content from the wire
+"basic_response" and a cert-stack "sk" are all that is used.
+
+We have a stack, loaded in setup_certs() if tls_verify_certificates
+was a file (not a directory, or "system"). It is unfortunate we
+cannot used the connection context store, as that would neatly
+handle the "system" case too, but there seems to be no library
+function for getting a stack from a store.
+[ In OpenSSL 1.1 - ? X509_STORE_CTX_get0_chain(ctx) ? ]
+We do not free the stack since it could be needed a second time for
+SNI handling.
+
+Separately we might try to replace using OCSP_basic_verify() - which seems to not
+be a public interface into the OpenSSL library (there's no manual entry) -
+But what with? We also use OCSP_basic_verify in the client stapling callback.
+And there we NEED it; we must verify that status... unless the
+library does it for us anyway? */
+if ((i = OCSP_basic_verify(basic_response, sk, NULL, verify_flags)) < 0)
+ {
+ DEBUG(D_tls)
+ {
+ ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
+ debug_printf("OCSP response verify failure: %s\n", US ssl_errstring);
+ }
+ goto bad;
+ }
-#ifdef SUPPORT_DANE
+/* Here's the simplifying assumption: there's only one response, for the
+one certificate we use, and nothing for anything else in a chain. If this
+proves false, we need to extract a cert id from our issued cert
+(tls_certificate) and use that for OCSP_resp_find_status() (which finds the
+right cert in the stack and then calls OCSP_single_get0_status()).
-/* This gets called *by* the dane library verify callback, which interposes
-itself.
+I'm hoping to avoid reworking a bunch more of how we handle state here.
+
+XXX that will change when we add support for (TLS1.3) whole-chain stapling
*/
-static int
-verify_callback_client_dane(int preverify_ok, X509_STORE_CTX * x509ctx)
-{
-X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx);
-uschar dn[256];
-int depth = X509_STORE_CTX_get_error_depth(x509ctx);
-#ifndef DISABLE_EVENT
-BOOL dummy_called, optional = FALSE;
-#endif
-if (!X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)))
+if (!(single_response = OCSP_resp_get0(basic_response, 0)))
{
- DEBUG(D_tls) debug_printf("X509_NAME_oneline() error\n");
- log_write(0, LOG_MAIN, "[%s] SSL verify error: internal error",
- deliver_host_address);
- return 0;
+ DEBUG(D_tls)
+ debug_printf("Unable to get first response from OCSP basic response.\n");
+ goto bad;
}
-dn[sizeof(dn)-1] = '\0';
-
-DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s depth %d %s\n",
- preverify_ok ? "ok":"BAD", depth, dn);
-
-#ifndef DISABLE_EVENT
- if (verify_event(&tls_out, cert, depth, dn,
- &dummy_called, &optional, US"DANE"))
- return 0; /* reject, with peercert set */
-#endif
-if (preverify_ok == 1)
+status = OCSP_single_get0_status(single_response, &reason, &rev, &thisupd, &nextupd);
+if (status != V_OCSP_CERTSTATUS_GOOD)
{
- tls_out.dane_verified = tls_out.certificate_verified = TRUE;
-#ifndef DISABLE_OCSP
- if (client_static_cbinfo->u_ocsp.client.verify_store)
- { /* client, wanting stapling */
- /* Add the server cert's signing chain as the one
- for the verification of the OCSP stapled information. */
+ DEBUG(D_tls) debug_printf("OCSP response bad cert status: %s (%d) %s (%d)\n",
+ OCSP_cert_status_str(status), status,
+ OCSP_crl_reason_str(reason), reason);
+ goto bad;
+ }
- if (!X509_STORE_add_cert(client_static_cbinfo->u_ocsp.client.verify_store,
- cert))
- ERR_clear_error();
- sk_X509_push(client_static_cbinfo->verify_stack, cert);
- }
-#endif
+if (!OCSP_check_validity(thisupd, nextupd, EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE))
+ {
+ DEBUG(D_tls) debug_printf("OCSP status invalid times.\n");
+ goto bad;
}
-else
+
+supply_response:
+ /* Add the resp to the list used by tls_server_stapling_cb() */
{
- int err = X509_STORE_CTX_get_error(x509ctx);
- DEBUG(D_tls)
- debug_printf(" - err %d '%s'\n", err, X509_verify_cert_error_string(err));
- if (err == X509_V_ERR_APPLICATION_VERIFICATION)
- preverify_ok = 1;
+ ocsp_resplist ** op = &state->u_ocsp.server.olist, * oentry;
+ while (oentry = *op)
+ op = &oentry->next;
+ *op = oentry = store_get(sizeof(ocsp_resplist), FALSE);
+ oentry->next = NULL;
+ oentry->resp = resp;
}
-return preverify_ok;
+return;
+
+bad:
+ if (f.running_in_test_harness)
+ {
+ extern char ** environ;
+ if (environ) for (uschar ** p = USS environ; *p; p++)
+ if (Ustrncmp(*p, "EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK", 42) == 0)
+ {
+ DEBUG(D_tls) debug_printf("Supplying known bad OCSP response\n");
+ goto supply_response;
+ }
+ }
+return;
}
-#endif /*SUPPORT_DANE*/
+static void
+ocsp_free_response_list(exim_openssl_state_st * cbinfo)
+{
+for (ocsp_resplist * olist = cbinfo->u_ocsp.server.olist; olist;
+ olist = olist->next)
+ OCSP_RESPONSE_free(olist->resp);
+cbinfo->u_ocsp.server.olist = NULL;
+}
+#endif /*!DISABLE_OCSP*/
-/*************************************************
-* Information callback *
-*************************************************/
-/* The SSL library functions call this from time to time to indicate what they
-are doing. We copy the string to the debugging output when TLS debugging has
-been requested.
-Arguments:
- s the SSL connection
- where
- ret
-Returns: nothing
-*/
-static void
-info_callback(SSL *s, int where, int ret)
+static int
+tls_add_certfile(SSL_CTX * sctx, exim_openssl_state_st * cbinfo, uschar * file,
+ uschar ** errstr)
{
-DEBUG(D_tls)
- {
- const uschar * str;
-
- if (where & SSL_ST_CONNECT)
- str = US"SSL_connect";
- else if (where & SSL_ST_ACCEPT)
- str = US"SSL_accept";
- else
- str = US"SSL info (undefined)";
+DEBUG(D_tls) debug_printf("tls_certificate file '%s'\n", file);
+if (!SSL_CTX_use_certificate_chain_file(sctx, CS file))
+ return tls_error(string_sprintf(
+ "SSL_CTX_use_certificate_chain_file file=%s", file),
+ cbinfo->host, NULL, errstr);
+return 0;
+}
- if (where & SSL_CB_LOOP)
- debug_printf("%s: %s\n", str, SSL_state_string_long(s));
- else if (where & SSL_CB_ALERT)
- debug_printf("SSL3 alert %s:%s:%s\n",
- str = where & SSL_CB_READ ? US"read" : US"write",
- SSL_alert_type_string_long(ret), SSL_alert_desc_string_long(ret));
- else if (where & SSL_CB_EXIT)
- if (ret == 0)
- debug_printf("%s: failed in %s\n", str, SSL_state_string_long(s));
- else if (ret < 0)
- debug_printf("%s: error in %s\n", str, SSL_state_string_long(s));
- else if (where & SSL_CB_HANDSHAKE_START)
- debug_printf("%s: hshake start: %s\n", str, SSL_state_string_long(s));
- else if (where & SSL_CB_HANDSHAKE_DONE)
- debug_printf("%s: hshake done: %s\n", str, SSL_state_string_long(s));
- }
+static int
+tls_add_pkeyfile(SSL_CTX * sctx, exim_openssl_state_st * cbinfo, uschar * file,
+ uschar ** errstr)
+{
+DEBUG(D_tls) debug_printf("tls_privatekey file '%s'\n", file);
+if (!SSL_CTX_use_PrivateKey_file(sctx, CS file, SSL_FILETYPE_PEM))
+ return tls_error(string_sprintf(
+ "SSL_CTX_use_PrivateKey_file file=%s", file), cbinfo->host, NULL, errstr);
+return 0;
}
-/*************************************************
-* Initialize for DH *
-*************************************************/
-/* If dhparam is set, expand it, and load up the parameters for DH encryption.
+/* Called once during tls_init and possibly again during TLS setup, for a
+new context, if Server Name Indication was used and tls_sni was seen in
+the certificate string.
Arguments:
- sctx The current SSL CTX (inbound or outbound)
- dhparam DH parameter file or fixed parameter identity string
- host connected host, if client; NULL if server
- errstr error string pointer
+ sctx the SSL_CTX* to update
+ state various parts of session state
+ errstr error string pointer
-Returns: TRUE if OK (nothing to set up, or setup worked)
+Returns: OK/DEFER/FAIL
*/
-static BOOL
-init_dh(SSL_CTX *sctx, uschar *dhparam, const host_item *host, uschar ** errstr)
+static int
+tls_expand_session_files(SSL_CTX * sctx, exim_openssl_state_st * state,
+ uschar ** errstr)
{
-BIO *bio;
-DH *dh;
-uschar *dhexpanded;
-const char *pem;
-int dh_bitsize;
-
-if (!expand_check(dhparam, US"tls_dhparam", &dhexpanded, errstr))
- return FALSE;
+uschar * expanded;
-if (!dhexpanded || !*dhexpanded)
- bio = BIO_new_mem_buf(CS std_dh_prime_default(), -1);
-else if (dhexpanded[0] == '/')
+if (!state->certificate)
{
- if (!(bio = BIO_new_file(CS dhexpanded, "r")))
- {
- tls_error(string_sprintf("could not read dhparams file %s", dhexpanded),
- host, US strerror(errno), errstr);
- return FALSE;
- }
+ if (!state->is_server) /* client */
+ return OK;
+ /* server */
+ if (tls_install_selfsign(sctx, errstr) != OK)
+ return DEFER;
}
else
{
- if (Ustrcmp(dhexpanded, "none") == 0)
- {
- DEBUG(D_tls) debug_printf("Requested no DH parameters.\n");
- return TRUE;
- }
-
- if (!(pem = std_dh_prime_named(dhexpanded)))
- {
- tls_error(string_sprintf("Unknown standard DH prime \"%s\"", dhexpanded),
- host, US strerror(errno), errstr);
- return FALSE;
- }
- bio = BIO_new_mem_buf(CS pem, -1);
- }
-
-if (!(dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL)))
- {
- BIO_free(bio);
- tls_error(string_sprintf("Could not read tls_dhparams \"%s\"", dhexpanded),
- host, NULL, errstr);
- return FALSE;
- }
+ int err;
-/* note: our default limit of 2236 is not a multiple of 8; the limit comes from
- * an NSS limit, and the GnuTLS APIs handle bit-sizes fine, so we went with
- * 2236. But older OpenSSL can only report in bytes (octets), not bits.
- * If someone wants to dance at the edge, then they can raise the limit or use
- * current libraries. */
-#ifdef EXIM_HAVE_OPENSSL_DH_BITS
-/* Added in commit 26c79d5641d; `git describe --contains` says OpenSSL_1_1_0-pre1~1022
- * This predates OpenSSL_1_1_0 (before a, b, ...) so is in all 1.1.0 */
-dh_bitsize = DH_bits(dh);
-#else
-dh_bitsize = 8 * DH_size(dh);
-#endif
+ if ( !reexpand_tls_files_for_sni
+ && ( Ustrstr(state->certificate, US"tls_sni")
+ || Ustrstr(state->certificate, US"tls_in_sni")
+ || Ustrstr(state->certificate, US"tls_out_sni")
+ ) )
+ reexpand_tls_files_for_sni = TRUE;
-/* Even if it is larger, we silently return success rather than cause things
- * to fail out, so that a too-large DH will not knock out all TLS; it's a
- * debatable choice. */
-if (dh_bitsize > tls_dh_max_bits)
- {
- DEBUG(D_tls)
- debug_printf("dhparams file %d bits, is > tls_dh_max_bits limit of %d\n",
- dh_bitsize, tls_dh_max_bits);
- }
-else
- {
- SSL_CTX_set_tmp_dh(sctx, dh);
- DEBUG(D_tls)
- debug_printf("Diffie-Hellman initialized from %s with %d-bit prime\n",
- dhexpanded ? dhexpanded : US"default", dh_bitsize);
- }
+ if (!expand_check(state->certificate, US"tls_certificate", &expanded, errstr))
+ return DEFER;
-DH_free(dh);
-BIO_free(bio);
+ if (expanded)
+ if (state->is_server)
+ {
+ const uschar * file_list = expanded;
+ int sep = 0;
+ uschar * file;
+#ifndef DISABLE_OCSP
+ const uschar * olist = state->u_ocsp.server.file;
+ int osep = 0;
+ uschar * ofile;
+ BOOL fmt_pem = FALSE;
-return TRUE;
-}
+ if (olist)
+ if (!expand_check(olist, US"tls_ocsp_file", USS &olist, errstr))
+ return DEFER;
+ if (olist && !*olist)
+ olist = NULL;
+ if ( state->u_ocsp.server.file_expanded && olist
+ && (Ustrcmp(olist, state->u_ocsp.server.file_expanded) == 0))
+ {
+ DEBUG(D_tls) debug_printf(" - value unchanged, using existing values\n");
+ olist = NULL;
+ }
+ else
+ {
+ ocsp_free_response_list(state);
+ state->u_ocsp.server.file_expanded = olist;
+ }
+#endif
+ while (file = string_nextinlist(&file_list, &sep, NULL, 0))
+ {
+ if ((err = tls_add_certfile(sctx, state, file, errstr)))
+ return err;
+#ifndef DISABLE_OCSP
+ if (olist)
+ if ((ofile = string_nextinlist(&olist, &osep, NULL, 0)))
+ {
+ if (Ustrncmp(ofile, US"PEM ", 4) == 0)
+ {
+ fmt_pem = TRUE;
+ ofile += 4;
+ }
+ else if (Ustrncmp(ofile, US"DER ", 4) == 0)
+ {
+ fmt_pem = FALSE;
+ ofile += 4;
+ }
+ ocsp_load_response(state, ofile, fmt_pem);
+ }
+ else
+ DEBUG(D_tls) debug_printf("ran out of ocsp file list\n");
+#endif
+ }
+ }
+ else /* would there ever be a need for multiple client certs? */
+ if ((err = tls_add_certfile(sctx, state, expanded, errstr)))
+ return err;
-/*************************************************
-* Initialize for ECDH *
-*************************************************/
+ if ( state->privatekey
+ && !expand_check(state->privatekey, US"tls_privatekey", &expanded, errstr))
+ return DEFER;
-/* Load parameters for ECDH encryption.
+ /* If expansion was forced to fail, key_expanded will be NULL. If the result
+ of the expansion is an empty string, ignore it also, and assume the private
+ key is in the same file as the certificate. */
-For now, we stick to NIST P-256 because: it's simple and easy to configure;
-it avoids any patent issues that might bite redistributors; despite events in
-the news and concerns over curve choices, we're not cryptographers, we're not
-pretending to be, and this is "good enough" to be better than no support,
-protecting against most adversaries. Given another year or two, there might
-be sufficient clarity about a "right" way forward to let us make an informed
-decision, instead of a knee-jerk reaction.
+ if (expanded && *expanded)
+ if (state->is_server)
+ {
+ const uschar * file_list = expanded;
+ int sep = 0;
+ uschar * file;
-Longer-term, we should look at supporting both various named curves and
-external files generated with "openssl ecparam", much as we do for init_dh().
-We should also support "none" as a value, to explicitly avoid initialisation.
+ while (file = string_nextinlist(&file_list, &sep, NULL, 0))
+ if ((err = tls_add_pkeyfile(sctx, state, file, errstr)))
+ return err;
+ }
+ else /* would there ever be a need for multiple client certs? */
+ if ((err = tls_add_pkeyfile(sctx, state, expanded, errstr)))
+ return err;
+ }
-Patches welcome.
+return OK;
+}
-Arguments:
- sctx The current SSL CTX (inbound or outbound)
- host connected host, if client; NULL if server
- errstr error string pointer
-Returns: TRUE if OK (nothing to set up, or setup worked)
-*/
-static BOOL
-init_ecdh(SSL_CTX * sctx, host_item * host, uschar ** errstr)
-{
-#ifdef OPENSSL_NO_ECDH
-return TRUE;
-#else
-EC_KEY * ecdh;
-uschar * exp_curve;
-int nid;
-BOOL rv;
+/**************************************************
+* One-time init credentials for server and client *
+**************************************************/
-if (host) /* No ECDH setup for clients, only for servers */
- return TRUE;
+static int
+server_load_ciphers(SSL_CTX * ctx, exim_openssl_state_st * state,
+ uschar * ciphers, uschar ** errstr)
+{
+for (uschar * s = ciphers; *s; s++ ) if (*s == '_') *s = '-';
+DEBUG(D_tls) debug_printf("required ciphers: %s\n", ciphers);
+if (!SSL_CTX_set_cipher_list(ctx, CS ciphers))
+ return tls_error(US"SSL_CTX_set_cipher_list", NULL, NULL, errstr);
+state->server_cipher_list = ciphers;
+return OK;
+}
-# ifndef EXIM_HAVE_ECDH
-DEBUG(D_tls)
- debug_printf("No OpenSSL API to define ECDH parameters, skipping\n");
-return TRUE;
-# else
-if (!expand_check(tls_eccurve, US"tls_eccurve", &exp_curve, errstr))
- return FALSE;
-if (!exp_curve || !*exp_curve)
- return TRUE;
-/* "auto" needs to be handled carefully.
- * OpenSSL < 1.0.2: we do not select anything, but fallback to prime256v1
- * OpenSSL < 1.1.0: we have to call SSL_CTX_set_ecdh_auto
- * (openssl/ssl.h defines SSL_CTRL_SET_ECDH_AUTO)
- * OpenSSL >= 1.1.0: we do not set anything, the libray does autoselection
- * https://github.com/openssl/openssl/commit/fe6ef2472db933f01b59cad82aa925736935984b
- */
-if (Ustrcmp(exp_curve, "auto") == 0)
- {
-#if OPENSSL_VERSION_NUMBER < 0x10002000L
- DEBUG(D_tls) debug_printf(
- "ECDH OpenSSL < 1.0.2: temp key parameter settings: overriding \"auto\" with \"prime256v1\"\n");
- exp_curve = US"prime256v1";
+static int
+lib_ctx_new(SSL_CTX ** ctxp, host_item * host, uschar ** errstr)
+{
+SSL_CTX * ctx;
+#ifdef EXIM_HAVE_OPENSSL_TLS_METHOD
+if (!(ctx = SSL_CTX_new(host ? TLS_client_method() : TLS_server_method())))
#else
-# if defined SSL_CTRL_SET_ECDH_AUTO
- DEBUG(D_tls) debug_printf(
- "ECDH OpenSSL 1.0.2+ temp key parameter settings: autoselection\n");
- SSL_CTX_set_ecdh_auto(sctx, 1);
- return TRUE;
-# else
- DEBUG(D_tls) debug_printf(
- "ECDH OpenSSL 1.1.0+ temp key parameter settings: default selection\n");
- return TRUE;
-# endif
+if (!(ctx = SSL_CTX_new(host ? SSLv23_client_method() : SSLv23_server_method())))
#endif
- }
+ return tls_error(US"SSL_CTX_new", host, NULL, errstr);
-DEBUG(D_tls) debug_printf("ECDH: curve '%s'\n", exp_curve);
-if ( (nid = OBJ_sn2nid (CCS exp_curve)) == NID_undef
-# ifdef EXIM_HAVE_OPENSSL_EC_NIST2NID
- && (nid = EC_curve_nist2nid(CCS exp_curve)) == NID_undef
-# endif
- )
- {
- tls_error(string_sprintf("Unknown curve name tls_eccurve '%s'", exp_curve),
- host, NULL, errstr);
- return FALSE;
- }
+/* Set up the information callback, which outputs if debugging is at a suitable
+level. */
-if (!(ecdh = EC_KEY_new_by_curve_name(nid)))
+DEBUG(D_tls)
{
- tls_error(US"Unable to create ec curve", host, NULL, errstr);
- return FALSE;
+ SSL_CTX_set_info_callback(ctx, (void (*)())info_callback);
+#if defined(EXIM_HAVE_OPESSL_TRACE) && !defined(OPENSSL_NO_SSL_TRACE)
+ /* this needs a debug build of OpenSSL */
+ SSL_CTX_set_msg_callback(ctx, (void (*)())SSL_trace);
+#endif
+#ifdef OPENSSL_HAVE_KEYLOG_CB
+ SSL_CTX_set_keylog_callback(ctx, (void (*)())keylog_callback);
+#endif
}
-/* The "tmp" in the name here refers to setting a temporary key
-not to the stability of the interface. */
-
-if ((rv = SSL_CTX_set_tmp_ecdh(sctx, ecdh) == 0))
- tls_error(string_sprintf("Error enabling '%s' curve", exp_curve), host, NULL, errstr);
-else
- DEBUG(D_tls) debug_printf("ECDH: enabled '%s' curve\n", exp_curve);
-
-EC_KEY_free(ecdh);
-return !rv;
-
-# endif /*EXIM_HAVE_ECDH*/
-#endif /*OPENSSL_NO_ECDH*/
+/* Automatically re-try reads/writes after renegotiation. */
+(void) SSL_CTX_set_mode(ctx, SSL_MODE_AUTO_RETRY);
+*ctxp = ctx;
+return OK;
}
+static unsigned
+tls_server_creds_init(void)
+{
+SSL_CTX * ctx;
+uschar * dummy_errstr;
+unsigned lifetime = 0;
+tls_openssl_init();
-#ifndef DISABLE_OCSP
-/*************************************************
-* Load OCSP information into state *
-*************************************************/
-/* Called to load the server OCSP response from the given file into memory, once
-caller has determined this is needed. Checks validity. Debugs a message
-if invalid.
-
-ASSUMES: single response, for single cert.
-
-Arguments:
- sctx the SSL_CTX* to update
- cbinfo various parts of session state
- expanded the filename putatively holding an OCSP response
+state_server.lib_state = null_tls_preload;
-*/
+if (lib_ctx_new(&ctx, NULL, &dummy_errstr) != OK)
+ return 0;
+state_server.lib_state.lib_ctx = ctx;
-static void
-ocsp_load_response(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo, const uschar *expanded)
-{
-BIO * bio;
-OCSP_RESPONSE * resp;
-OCSP_BASICRESP * basic_response;
-OCSP_SINGLERESP * single_response;
-ASN1_GENERALIZEDTIME * rev, * thisupd, * nextupd;
-STACK_OF(X509) * sk;
-unsigned long verify_flags;
-int status, reason, i;
+/* Preload DH params and EC curve */
-cbinfo->u_ocsp.server.file_expanded = string_copy(expanded);
-if (cbinfo->u_ocsp.server.response)
+if (opt_unset_or_noexpand(tls_dhparam))
{
- OCSP_RESPONSE_free(cbinfo->u_ocsp.server.response);
- cbinfo->u_ocsp.server.response = NULL;
+ DEBUG(D_tls) debug_printf("TLS: preloading DH params for server\n");
+ if (init_dh(ctx, tls_dhparam, NULL, &dummy_errstr))
+ state_server.lib_state.dh = TRUE;
}
-
-if (!(bio = BIO_new_file(CS cbinfo->u_ocsp.server.file_expanded, "rb")))
+if (opt_unset_or_noexpand(tls_eccurve))
{
- DEBUG(D_tls) debug_printf("Failed to open OCSP response file \"%s\"\n",
- cbinfo->u_ocsp.server.file_expanded);
- return;
+ DEBUG(D_tls) debug_printf("TLS: preloading ECDH curve for server\n");
+ if (init_ecdh(ctx, NULL, &dummy_errstr))
+ state_server.lib_state.ecdh = TRUE;
}
-resp = d2i_OCSP_RESPONSE_bio(bio, NULL);
-BIO_free(bio);
-if (!resp)
+#if defined(EXIM_HAVE_INOTIFY) || defined(EXIM_HAVE_KEVENT)
+/* If we can, preload the server-side cert, key and ocsp */
+
+if ( opt_set_and_noexpand(tls_certificate)
+# ifndef DISABLE_OCSP
+ && opt_unset_or_noexpand(tls_ocsp_file)
+#endif
+ && opt_unset_or_noexpand(tls_privatekey))
{
- DEBUG(D_tls) debug_printf("Error reading OCSP response.\n");
- return;
+ /* Set watches on the filenames. The implementation does de-duplication
+ so we can just blindly do them all. */
+
+ if ( tls_set_watch(tls_certificate, TRUE)
+# ifndef DISABLE_OCSP
+ && tls_set_watch(tls_ocsp_file, TRUE)
+#endif
+ && tls_set_watch(tls_privatekey, TRUE))
+ {
+ state_server.certificate = tls_certificate;
+ state_server.privatekey = tls_privatekey;
+#ifndef DISABLE_OCSP
+ state_server.u_ocsp.server.file = tls_ocsp_file;
+#endif
+
+ DEBUG(D_tls) debug_printf("TLS: preloading server certs\n");
+ if (tls_expand_session_files(ctx, &state_server, &dummy_errstr) == OK)
+ state_server.lib_state.conn_certs = TRUE;
+ }
+ }
+else if ( !tls_certificate && !tls_privatekey
+# ifndef DISABLE_OCSP
+ && !tls_ocsp_file
+#endif
+ )
+ { /* Generate & preload a selfsigned cert. No files to watch. */
+ if (tls_expand_session_files(ctx, &state_server, &dummy_errstr) == OK)
+ {
+ state_server.lib_state.conn_certs = TRUE;
+ lifetime = f.running_in_test_harness ? 2 : 60 * 60; /* 1 hour */
+ }
}
+else
+ DEBUG(D_tls) debug_printf("TLS: not preloading server certs\n");
-if ((status = OCSP_response_status(resp)) != OCSP_RESPONSE_STATUS_SUCCESSFUL)
+
+/* If we can, preload the Authorities for checking client certs against.
+Actual choice to do verify is made (tls_{,try_}verify_hosts)
+at TLS conn startup */
+
+if ( opt_set_and_noexpand(tls_verify_certificates)
+ && opt_unset_or_noexpand(tls_crl))
{
- DEBUG(D_tls) debug_printf("OCSP response not valid: %s (%d)\n",
- OCSP_response_status_str(status), status);
- goto bad;
+ /* Watch the default dir also as they are always included */
+
+ if ( tls_set_watch(CUS X509_get_default_cert_file(), FALSE)
+ && tls_set_watch(tls_verify_certificates, FALSE)
+ && tls_set_watch(tls_crl, FALSE))
+ {
+ DEBUG(D_tls) debug_printf("TLS: preloading CA bundle for server\n");
+
+ if (setup_certs(ctx, tls_verify_certificates, tls_crl, NULL, &dummy_errstr)
+ == OK)
+ state_server.lib_state.cabundle = TRUE;
+ }
}
+else
+ DEBUG(D_tls) debug_printf("TLS: not preloading CA bundle for server\n");
+#endif /* EXIM_HAVE_INOTIFY */
-if (!(basic_response = OCSP_response_get1_basic(resp)))
+
+/* If we can, preload the ciphers control string */
+
+if (opt_set_and_noexpand(tls_require_ciphers))
{
- DEBUG(D_tls)
- debug_printf("OCSP response parse error: unable to extract basic response.\n");
- goto bad;
+ DEBUG(D_tls) debug_printf("TLS: preloading cipher list for server\n");
+ if (server_load_ciphers(ctx, &state_server, tls_require_ciphers,
+ &dummy_errstr) == OK)
+ state_server.lib_state.pri_string = TRUE;
}
+else
+ DEBUG(D_tls) debug_printf("TLS: not preloading cipher list for server\n");
+return lifetime;
+}
-sk = cbinfo->verify_stack;
-verify_flags = OCSP_NOVERIFY; /* check sigs, but not purpose */
-
-/* May need to expose ability to adjust those flags?
-OCSP_NOSIGS OCSP_NOVERIFY OCSP_NOCHAIN OCSP_NOCHECKS OCSP_NOEXPLICIT
-OCSP_TRUSTOTHER OCSP_NOINTERN */
-/* This does a full verify on the OCSP proof before we load it for serving
-up; possibly overkill - just date-checks might be nice enough.
-OCSP_basic_verify takes a "store" arg, but does not
-use it for the chain verification, which is all we do
-when OCSP_NOVERIFY is set. The content from the wire
-"basic_response" and a cert-stack "sk" are all that is used.
-We have a stack, loaded in setup_certs() if tls_verify_certificates
-was a file (not a directory, or "system"). It is unfortunate we
-cannot used the connection context store, as that would neatly
-handle the "system" case too, but there seems to be no library
-function for getting a stack from a store.
-[ In OpenSSL 1.1 - ? X509_STORE_CTX_get0_chain(ctx) ? ]
-We do not free the stack since it could be needed a second time for
-SNI handling.
+/* Preload whatever creds are static, onto a transport. The client can then
+just copy the pointer as it starts up.
+Called from the daemon after a cache-invalidate with watch set; called from
+a queue-run startup with watch clear. */
-Separately we might try to replace using OCSP_basic_verify() - which seems to not
-be a public interface into the OpenSSL library (there's no manual entry) -
-But what with? We also use OCSP_basic_verify in the client stapling callback.
-And there we NEED it; we must verify that status... unless the
-library does it for us anyway? */
+static void
+tls_client_creds_init(transport_instance * t, BOOL watch)
+{
+smtp_transport_options_block * ob = t->options_block;
+exim_openssl_state_st tpt_dummy_state;
+host_item * dummy_host = (host_item *)1;
+uschar * dummy_errstr;
+SSL_CTX * ctx;
-if ((i = OCSP_basic_verify(basic_response, sk, NULL, verify_flags)) < 0)
- {
- DEBUG(D_tls)
- {
- ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
- debug_printf("OCSP response verify failure: %s\n", US ssl_errstring);
- }
- goto bad;
- }
+tls_openssl_init();
-/* Here's the simplifying assumption: there's only one response, for the
-one certificate we use, and nothing for anything else in a chain. If this
-proves false, we need to extract a cert id from our issued cert
-(tls_certificate) and use that for OCSP_resp_find_status() (which finds the
-right cert in the stack and then calls OCSP_single_get0_status()).
+ob->tls_preload = null_tls_preload;
+if (lib_ctx_new(&ctx, dummy_host, &dummy_errstr) != OK)
+ return;
+ob->tls_preload.lib_ctx = ctx;
-I'm hoping to avoid reworking a bunch more of how we handle state here. */
+tpt_dummy_state.lib_state = ob->tls_preload;
-if (!(single_response = OCSP_resp_get0(basic_response, 0)))
+if (opt_unset_or_noexpand(tls_dhparam))
{
- DEBUG(D_tls)
- debug_printf("Unable to get first response from OCSP basic response.\n");
- goto bad;
+ DEBUG(D_tls) debug_printf("TLS: preloading DH params for transport '%s'\n", t->name);
+ if (init_dh(ctx, tls_dhparam, NULL, &dummy_errstr))
+ ob->tls_preload.dh = TRUE;
}
-
-status = OCSP_single_get0_status(single_response, &reason, &rev, &thisupd, &nextupd);
-if (status != V_OCSP_CERTSTATUS_GOOD)
+if (opt_unset_or_noexpand(tls_eccurve))
{
- DEBUG(D_tls) debug_printf("OCSP response bad cert status: %s (%d) %s (%d)\n",
- OCSP_cert_status_str(status), status,
- OCSP_crl_reason_str(reason), reason);
- goto bad;
+ DEBUG(D_tls) debug_printf("TLS: preloading ECDH curve for transport '%s'\n", t->name);
+ if (init_ecdh(ctx, NULL, &dummy_errstr))
+ ob->tls_preload.ecdh = TRUE;
}
-if (!OCSP_check_validity(thisupd, nextupd, EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE))
+#if defined(EXIM_HAVE_INOTIFY) || defined(EXIM_HAVE_KEVENT)
+if ( opt_set_and_noexpand(ob->tls_certificate)
+ && opt_unset_or_noexpand(ob->tls_privatekey))
{
- DEBUG(D_tls) debug_printf("OCSP status invalid times.\n");
- goto bad;
+ if ( !watch
+ || ( tls_set_watch(ob->tls_certificate, FALSE)
+ && tls_set_watch(ob->tls_privatekey, FALSE)
+ ) )
+ {
+ uschar * pkey = ob->tls_privatekey;
+
+ DEBUG(D_tls)
+ debug_printf("TLS: preloading client certs for transport '%s'\n",t->name);
+
+ if ( tls_add_certfile(ctx, &tpt_dummy_state, ob->tls_certificate,
+ &dummy_errstr) == 0
+ && tls_add_pkeyfile(ctx, &tpt_dummy_state,
+ pkey ? pkey : ob->tls_certificate,
+ &dummy_errstr) == 0
+ )
+ ob->tls_preload.conn_certs = TRUE;
+ }
}
+else
+ DEBUG(D_tls)
+ debug_printf("TLS: not preloading client certs, for transport '%s'\n", t->name);
-supply_response:
- cbinfo->u_ocsp.server.response = resp; /*XXX stack?*/
-return;
-bad:
- if (f.running_in_test_harness)
+if ( opt_set_and_noexpand(ob->tls_verify_certificates)
+ && opt_unset_or_noexpand(ob->tls_crl))
+ {
+ if ( !watch
+ || tls_set_watch(CUS X509_get_default_cert_file(), FALSE)
+ && tls_set_watch(ob->tls_verify_certificates, FALSE)
+ && tls_set_watch(ob->tls_crl, FALSE)
+ )
{
- extern char ** environ;
- uschar ** p;
- if (environ) for (p = USS environ; *p; p++)
- if (Ustrncmp(*p, "EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK", 42) == 0)
- {
- DEBUG(D_tls) debug_printf("Supplying known bad OCSP response\n");
- goto supply_response;
- }
- }
-return;
-}
-#endif /*!DISABLE_OCSP*/
-
+ DEBUG(D_tls)
+ debug_printf("TLS: preloading CA bundle for transport '%s'\n", t->name);
+ if (setup_certs(ctx, ob->tls_verify_certificates,
+ ob->tls_crl, dummy_host, &dummy_errstr) == OK)
+ ob->tls_preload.cabundle = TRUE;
+ }
+ }
+else
+ DEBUG(D_tls)
+ debug_printf("TLS: not preloading CA bundle, for transport '%s'\n", t->name);
+#endif /*EXIM_HAVE_INOTIFY*/
+}
-/* Create and install a selfsigned certificate, for use in server mode */
-static int
-tls_install_selfsign(SSL_CTX * sctx, uschar ** errstr)
+#if defined(EXIM_HAVE_INOTIFY) || defined(EXIM_HAVE_KEVENT)
+/* Invalidate the creds cached, by dropping the current ones.
+Call when we notice one of the source files has changed. */
+
+static void
+tls_server_creds_invalidate(void)
{
-X509 * x509 = NULL;
-EVP_PKEY * pkey;
-RSA * rsa;
-X509_NAME * name;
-uschar * where;
+SSL_CTX_free(state_server.lib_state.lib_ctx);
+state_server.lib_state = null_tls_preload;
+}
-where = US"allocating pkey";
-if (!(pkey = EVP_PKEY_new()))
- goto err;
-where = US"allocating cert";
-if (!(x509 = X509_new()))
- goto err;
+static void
+tls_client_creds_invalidate(transport_instance * t)
+{
+smtp_transport_options_block * ob = t->options_block;
+SSL_CTX_free(ob->tls_preload.lib_ctx);
+ob->tls_preload = null_tls_preload;
+}
-where = US"generating pkey";
-if (!(rsa = rsa_callback(NULL, 0, 2048)))
- goto err;
+#else
-where = US"assigning pkey";
-if (!EVP_PKEY_assign_RSA(pkey, rsa))
- goto err;
+static void
+tls_server_creds_invalidate(void)
+{ return; }
-X509_set_version(x509, 2); /* N+1 - version 3 */
-ASN1_INTEGER_set(X509_get_serialNumber(x509), 1);
-X509_gmtime_adj(X509_get_notBefore(x509), 0);
-X509_gmtime_adj(X509_get_notAfter(x509), (long)60 * 60); /* 1 hour */
-X509_set_pubkey(x509, pkey);
+static void
+tls_client_creds_invalidate(transport_instance * t)
+{ return; }
-name = X509_get_subject_name(x509);
-X509_NAME_add_entry_by_txt(name, "C",
- MBSTRING_ASC, CUS "UK", -1, -1, 0);
-X509_NAME_add_entry_by_txt(name, "O",
- MBSTRING_ASC, CUS "Exim Developers", -1, -1, 0);
-X509_NAME_add_entry_by_txt(name, "CN",
- MBSTRING_ASC, CUS smtp_active_hostname, -1, -1, 0);
-X509_set_issuer_name(x509, name);
+#endif /*EXIM_HAVE_INOTIFY*/
-where = US"signing cert";
-if (!X509_sign(x509, pkey, EVP_md5()))
- goto err;
-where = US"installing selfsign cert";
-if (!SSL_CTX_use_certificate(sctx, x509))
- goto err;
+/* Extreme debug
+#ifndef DISABLE_OCSP
+void
+x509_store_dump_cert_s_names(X509_STORE * store)
+{
+STACK_OF(X509_OBJECT) * roots= store->objs;
+static uschar name[256];
-where = US"installing selfsign key";
-if (!SSL_CTX_use_PrivateKey(sctx, pkey))
- goto err;
+for (int i= 0; i < sk_X509_OBJECT_num(roots); i++)
+ {
+ X509_OBJECT * tmp_obj= sk_X509_OBJECT_value(roots, i);
+ if(tmp_obj->type == X509_LU_X509)
+ {
+ X509_NAME * sn = X509_get_subject_name(tmp_obj->data.x509);
+ if (X509_NAME_oneline(sn, CS name, sizeof(name)))
+ {
+ name[sizeof(name)-1] = '\0';
+ debug_printf(" %s\n", name);
+ }
+ }
+ }
+}
+#endif
+*/
-return OK;
-err:
- (void) tls_error(where, NULL, NULL, errstr);
- if (x509) X509_free(x509);
- if (pkey) EVP_PKEY_free(pkey);
- return DEFER;
-}
+#ifndef DISABLE_TLS_RESUME
+/* Manage the keysets used for encrypting the session tickets, on the server. */
+typedef struct { /* Session ticket encryption key */
+ uschar name[16];
+ const EVP_CIPHER * aes_cipher;
+ uschar aes_key[32]; /* size needed depends on cipher. aes_128 implies 128/8 = 16? */
+ const EVP_MD * hmac_hash;
+ uschar hmac_key[16];
+ time_t renew;
+ time_t expire;
+} exim_stek;
+static exim_stek exim_tk; /* current key */
+static exim_stek exim_tk_old; /* previous key */
-static int
-tls_add_certfile(SSL_CTX * sctx, tls_ext_ctx_cb * cbinfo, uschar * file,
- uschar ** errstr)
+static void
+tk_init(void)
{
-DEBUG(D_tls) debug_printf("tls_certificate file %s\n", file);
-if (!SSL_CTX_use_certificate_chain_file(sctx, CS file))
- return tls_error(string_sprintf(
- "SSL_CTX_use_certificate_chain_file file=%s", file),
- cbinfo->host, NULL, errstr);
-return 0;
-}
+time_t t = time(NULL);
-static int
-tls_add_pkeyfile(SSL_CTX * sctx, tls_ext_ctx_cb * cbinfo, uschar * file,
- uschar ** errstr)
-{
-DEBUG(D_tls) debug_printf("tls_privatekey file %s\n", file);
-if (!SSL_CTX_use_PrivateKey_file(sctx, CS file, SSL_FILETYPE_PEM))
- return tls_error(string_sprintf(
- "SSL_CTX_use_PrivateKey_file file=%s", file), cbinfo->host, NULL, errstr);
-return 0;
-}
+if (exim_tk.name[0])
+ {
+ if (exim_tk.renew >= t) return;
+ exim_tk_old = exim_tk;
+ }
+if (f.running_in_test_harness) ssl_session_timeout = 6;
-/*************************************************
-* Expand key and cert file specs *
-*************************************************/
+DEBUG(D_tls) debug_printf("OpenSSL: %s STEK\n", exim_tk.name[0] ? "rotating" : "creating");
+if (RAND_bytes(exim_tk.aes_key, sizeof(exim_tk.aes_key)) <= 0) return;
+if (RAND_bytes(exim_tk.hmac_key, sizeof(exim_tk.hmac_key)) <= 0) return;
+if (RAND_bytes(exim_tk.name+1, sizeof(exim_tk.name)-1) <= 0) return;
-/* Called once during tls_init and possibly again during TLS setup, for a
-new context, if Server Name Indication was used and tls_sni was seen in
-the certificate string.
+exim_tk.name[0] = 'E';
+exim_tk.aes_cipher = EVP_aes_256_cbc();
+exim_tk.hmac_hash = EVP_sha256();
+exim_tk.expire = t + ssl_session_timeout;
+exim_tk.renew = t + ssl_session_timeout/2;
+}
-Arguments:
- sctx the SSL_CTX* to update
- cbinfo various parts of session state
- errstr error string pointer
+static exim_stek *
+tk_current(void)
+{
+if (!exim_tk.name[0]) return NULL;
+return &exim_tk;
+}
-Returns: OK/DEFER/FAIL
-*/
+static exim_stek *
+tk_find(const uschar * name)
+{
+return memcmp(name, exim_tk.name, sizeof(exim_tk.name)) == 0 ? &exim_tk
+ : memcmp(name, exim_tk_old.name, sizeof(exim_tk_old.name)) == 0 ? &exim_tk_old
+ : NULL;
+}
+/* Callback for session tickets, on server */
static int
-tls_expand_session_files(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo,
- uschar ** errstr)
+ticket_key_callback(SSL * ssl, uschar key_name[16],
+ uschar * iv, EVP_CIPHER_CTX * c_ctx, HMAC_CTX * hctx, int enc)
{
-uschar *expanded;
+tls_support * tlsp = state_server.tlsp;
+exim_stek * key;
-if (!cbinfo->certificate)
+if (enc)
{
- if (!cbinfo->is_server) /* client */
- return OK;
- /* server */
- if (tls_install_selfsign(sctx, errstr) != OK)
- return DEFER;
- }
-else
- {
- int err;
-
- if (Ustrstr(cbinfo->certificate, US"tls_sni") ||
- Ustrstr(cbinfo->certificate, US"tls_in_sni") ||
- Ustrstr(cbinfo->certificate, US"tls_out_sni")
- )
- reexpand_tls_files_for_sni = TRUE;
-
- if (!expand_check(cbinfo->certificate, US"tls_certificate", &expanded, errstr))
- return DEFER;
-
- if (expanded)
- if (cbinfo->is_server)
- {
- const uschar * file_list = expanded;
- int sep = 0;
- uschar * file;
-
- while (file = string_nextinlist(&file_list, &sep, NULL, 0))
- if ((err = tls_add_certfile(sctx, cbinfo, file, errstr)))
- return err;
- }
- else /* would there ever be a need for multiple client certs? */
- if ((err = tls_add_certfile(sctx, cbinfo, expanded, errstr)))
- return err;
+ DEBUG(D_tls) debug_printf("ticket_key_callback: create new session\n");
+ tlsp->resumption |= RESUME_CLIENT_REQUESTED;
- if ( cbinfo->privatekey
- && !expand_check(cbinfo->privatekey, US"tls_privatekey", &expanded, errstr))
- return DEFER;
+ if (RAND_bytes(iv, EVP_MAX_IV_LENGTH) <= 0)
+ return -1; /* insufficient random */
- /* If expansion was forced to fail, key_expanded will be NULL. If the result
- of the expansion is an empty string, ignore it also, and assume the private
- key is in the same file as the certificate. */
+ if (!(key = tk_current())) /* current key doesn't exist or isn't valid */
+ return 0; /* key couldn't be created */
+ memcpy(key_name, key->name, 16);
+ DEBUG(D_tls) debug_printf("STEK expire " TIME_T_FMT "\n", key->expire - time(NULL));
- if (expanded && *expanded)
- if (cbinfo->is_server)
- {
- const uschar * file_list = expanded;
- int sep = 0;
- uschar * file;
+ /*XXX will want these dependent on the ssl session strength */
+ HMAC_Init_ex(hctx, key->hmac_key, sizeof(key->hmac_key),
+ key->hmac_hash, NULL);
+ EVP_EncryptInit_ex(c_ctx, key->aes_cipher, NULL, key->aes_key, iv);
- while (file = string_nextinlist(&file_list, &sep, NULL, 0))
- if ((err = tls_add_pkeyfile(sctx, cbinfo, file, errstr)))
- return err;
- }
- else /* would there ever be a need for multiple client certs? */
- if ((err = tls_add_pkeyfile(sctx, cbinfo, expanded, errstr)))
- return err;
+ DEBUG(D_tls) debug_printf("ticket created\n");
+ return 1;
}
-
-#ifndef DISABLE_OCSP
-if (cbinfo->is_server && cbinfo->u_ocsp.server.file)
+else
{
- /*XXX stack*/
- if (!expand_check(cbinfo->u_ocsp.server.file, US"tls_ocsp_file", &expanded, errstr))
- return DEFER;
+ time_t now = time(NULL);
- if (expanded && *expanded)
+ DEBUG(D_tls) debug_printf("ticket_key_callback: retrieve session\n");
+ tlsp->resumption |= RESUME_CLIENT_SUGGESTED;
+
+ if (!(key = tk_find(key_name)) || key->expire < now)
{
- DEBUG(D_tls) debug_printf("tls_ocsp_file %s\n", expanded);
- if ( cbinfo->u_ocsp.server.file_expanded
- && (Ustrcmp(expanded, cbinfo->u_ocsp.server.file_expanded) == 0))
+ DEBUG(D_tls)
{
- DEBUG(D_tls) debug_printf(" - value unchanged, using existing values\n");
+ debug_printf("ticket not usable (%s)\n", key ? "expired" : "not found");
+ if (key) debug_printf("STEK expire " TIME_T_FMT "\n", key->expire - now);
}
- else
- ocsp_load_response(sctx, cbinfo, expanded);
+ return 0;
}
+
+ HMAC_Init_ex(hctx, key->hmac_key, sizeof(key->hmac_key),
+ key->hmac_hash, NULL);
+ EVP_DecryptInit_ex(c_ctx, key->aes_cipher, NULL, key->aes_key, iv);
+
+ DEBUG(D_tls) debug_printf("ticket usable, STEK expire " TIME_T_FMT "\n", key->expire - now);
+
+ /* The ticket lifetime and renewal are the same as the STEK lifetime and
+ renewal, which is overenthusiastic. A factor of, say, 3x longer STEK would
+ be better. To do that we'd have to encode ticket lifetime in the name as
+ we don't yet see the restored session. Could check posthandshake for TLS1.3
+ and trigger a new ticket then, but cannot do that for TLS1.2 */
+ return key->renew < now ? 2 : 1;
}
+}
#endif
-return OK;
-}
+static void
+setup_cert_verify(SSL_CTX * ctx, BOOL optional,
+ int (*cert_vfy_cb)(int, X509_STORE_CTX *))
+{
+/* If verification is optional, don't fail if no certificate */
+
+SSL_CTX_set_verify(ctx,
+ SSL_VERIFY_PEER | (optional ? 0 : SSL_VERIFY_FAIL_IF_NO_PEER_CERT),
+ cert_vfy_cb);
+}
/*************************************************
arg Callback of "our" registered data
Returns: SSL_TLSEXT_ERR_{OK,ALERT_WARNING,ALERT_FATAL,NOACK}
+
+XXX might need to change to using ClientHello callback,
+per https://www.openssl.org/docs/manmaster/man3/SSL_client_hello_cb_fn.html
*/
#ifdef EXIM_HAVE_OPENSSL_TLSEXT
tls_servername_cb(SSL *s, int *ad ARG_UNUSED, void *arg)
{
const char *servername = SSL_get_servername(s, TLSEXT_NAMETYPE_host_name);
-tls_ext_ctx_cb *cbinfo = (tls_ext_ctx_cb *) arg;
+exim_openssl_state_st *state = (exim_openssl_state_st *) arg;
int rc;
int old_pool = store_pool;
uschar * dummy_errstr;
/* Make the extension value available for expansion */
store_pool = POOL_PERM;
-tls_in.sni = string_copy(US servername);
+tls_in.sni = string_copy_taint(US servername, TRUE);
store_pool = old_pool;
if (!reexpand_tls_files_for_sni)
not confident that memcpy wouldn't break some internal reference counting.
Especially since there's a references struct member, which would be off. */
-#ifdef EXIM_HAVE_OPENSSL_TLS_METHOD
-if (!(server_sni = SSL_CTX_new(TLS_server_method())))
-#else
-if (!(server_sni = SSL_CTX_new(SSLv23_server_method())))
-#endif
- {
- ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
- DEBUG(D_tls) debug_printf("SSL_CTX_new() failed: %s\n", ssl_errstring);
+if (lib_ctx_new(&server_sni, NULL, &dummy_errstr) != OK)
goto bad;
- }
/* Not sure how many of these are actually needed, since SSL object
already exists. Might even need this selfsame callback, for reneg? */
-SSL_CTX_set_info_callback(server_sni, SSL_CTX_get_info_callback(server_ctx));
-SSL_CTX_set_mode(server_sni, SSL_CTX_get_mode(server_ctx));
-SSL_CTX_set_options(server_sni, SSL_CTX_get_options(server_ctx));
-SSL_CTX_set_timeout(server_sni, SSL_CTX_get_timeout(server_ctx));
-SSL_CTX_set_tlsext_servername_callback(server_sni, tls_servername_cb);
-SSL_CTX_set_tlsext_servername_arg(server_sni, cbinfo);
+ {
+ SSL_CTX * ctx = state_server.lib_state.lib_ctx;
+ SSL_CTX_set_info_callback(server_sni, SSL_CTX_get_info_callback(ctx));
+ SSL_CTX_set_mode(server_sni, SSL_CTX_get_mode(ctx));
+ SSL_CTX_set_options(server_sni, SSL_CTX_get_options(ctx));
+ SSL_CTX_set_timeout(server_sni, SSL_CTX_get_timeout(ctx));
+ SSL_CTX_set_tlsext_servername_callback(server_sni, tls_servername_cb);
+ SSL_CTX_set_tlsext_servername_arg(server_sni, state);
+ }
-if ( !init_dh(server_sni, cbinfo->dhparam, NULL, &dummy_errstr)
+if ( !init_dh(server_sni, state->dhparam, NULL, &dummy_errstr)
|| !init_ecdh(server_sni, NULL, &dummy_errstr)
)
goto bad;
-if ( cbinfo->server_cipher_list
- && !SSL_CTX_set_cipher_list(server_sni, CS cbinfo->server_cipher_list))
+if ( state->server_cipher_list
+ && !SSL_CTX_set_cipher_list(server_sni, CS state->server_cipher_list))
goto bad;
#ifndef DISABLE_OCSP
-if (cbinfo->u_ocsp.server.file)
+if (state->u_ocsp.server.file)
{
SSL_CTX_set_tlsext_status_cb(server_sni, tls_server_stapling_cb);
- SSL_CTX_set_tlsext_status_arg(server_sni, cbinfo);
+ SSL_CTX_set_tlsext_status_arg(server_sni, state);
}
#endif
-if ((rc = setup_certs(server_sni, tls_verify_certificates, tls_crl, NULL, FALSE,
- verify_callback_server, &dummy_errstr)) != OK)
- goto bad;
+ {
+ uschar * expcerts;
+ if ( !expand_check(tls_verify_certificates, US"tls_verify_certificates",
+ &expcerts, &dummy_errstr)
+ || (rc = setup_certs(server_sni, expcerts, tls_crl, NULL,
+ &dummy_errstr)) != OK)
+ goto bad;
+
+ if (expcerts && *expcerts)
+ setup_cert_verify(server_sni, FALSE, verify_callback_server);
+ }
/* do this after setup_certs, because this can require the certs for verifying
OCSP information. */
-if ((rc = tls_expand_session_files(server_sni, cbinfo, &dummy_errstr)) != OK)
+if ((rc = tls_expand_session_files(server_sni, state, &dummy_errstr)) != OK)
goto bad;
DEBUG(D_tls) debug_printf("Switching SSL context.\n");
SSL_set_SSL_CTX(s, server_sni);
return SSL_TLSEXT_ERR_OK;
-bad: return SSL_TLSEXT_ERR_ALERT_FATAL;
-}
-#endif /* EXIM_HAVE_OPENSSL_TLSEXT */
+bad: return SSL_TLSEXT_ERR_ALERT_FATAL;
+}
+#endif /* EXIM_HAVE_OPENSSL_TLSEXT */
+
+
+
+
+#ifdef EXIM_HAVE_ALPN
+/*************************************************
+* Callback to handle ALPN *
+*************************************************/
+
+/* Called on server if tls_alpn nonblank after expansion,
+when client offers ALPN, after the SNI callback.
+If set and not matching the list then we dump the connection */
+
+static int
+tls_server_alpn_cb(SSL *ssl, const uschar ** out, uschar * outlen,
+ const uschar * in, unsigned int inlen, void * arg)
+{
+server_seen_alpn = TRUE;
+DEBUG(D_tls)
+ {
+ debug_printf("Received TLS ALPN offer:");
+ for (int pos = 0, siz; pos < inlen; pos += siz+1)
+ {
+ siz = in[pos];
+ if (pos + 1 + siz > inlen) siz = inlen - pos - 1;
+ debug_printf(" '%.*s'", siz, in + pos + 1);
+ }
+ debug_printf(". Our list: '%s'\n", tls_alpn);
+ }
+
+/* Look for an acceptable ALPN */
+
+if ( inlen > 1 /* at least one name */
+ && in[0]+1 == inlen /* filling the vector, so exactly one name */
+ )
+ {
+ const uschar * list = tls_alpn;
+ int sep = 0;
+ for (uschar * name; name = string_nextinlist(&list, &sep, NULL, 0); )
+ if (Ustrncmp(in+1, name, in[0]) == 0)
+ {
+ *out = in+1; /* we checked for exactly one, so can just point to it */
+ *outlen = inlen;
+ return SSL_TLSEXT_ERR_OK; /* use ALPN */
+ }
+ }
+
+/* More than one name from clilent, or name did not match our list. */
+
+/* This will be fatal to the TLS conn; would be nice to kill TCP also.
+Maybe as an option in future; for now leave control to the config (must-tls). */
+DEBUG(D_tls) debug_printf("TLS ALPN rejected\n");
+return SSL_TLSEXT_ERR_ALERT_FATAL;
+}
+#endif /* EXIM_HAVE_ALPN */
static int
tls_server_stapling_cb(SSL *s, void *arg)
{
-const tls_ext_ctx_cb *cbinfo = (tls_ext_ctx_cb *) arg;
-uschar *response_der; /*XXX blob */
+const exim_openssl_state_st * state = arg;
+ocsp_resplist * olist = state->u_ocsp.server.olist;
+uschar * response_der; /*XXX blob */
int response_der_len;
-/*XXX stack: use SSL_get_certificate() to see which cert; from that work
-out which ocsp blob to send. Unfortunately, SSL_get_certificate is known
-buggy in current OpenSSL; it returns the last cert loaded always rather than
-the one actually presented. So we can't support a stack of OCSP proofs at
-this time. */
-
DEBUG(D_tls)
- debug_printf("Received TLS status request (OCSP stapling); %s response\n",
- cbinfo->u_ocsp.server.response ? "have" : "lack");
+ debug_printf("Received TLS status request (OCSP stapling); %s response list\n",
+ olist ? "have" : "lack");
tls_in.ocsp = OCSP_NOT_RESP;
-if (!cbinfo->u_ocsp.server.response)
+if (!olist)
+ return SSL_TLSEXT_ERR_NOACK;
+
+#ifdef EXIM_HAVE_OPESSL_GET0_SERIAL
+ {
+ const X509 * cert_sent = SSL_get_certificate(s);
+ const ASN1_INTEGER * cert_serial = X509_get0_serialNumber(cert_sent);
+ const BIGNUM * cert_bn = ASN1_INTEGER_to_BN(cert_serial, NULL);
+
+ for (; olist; olist = olist->next)
+ {
+ OCSP_BASICRESP * bs = OCSP_response_get1_basic(olist->resp);
+ const OCSP_SINGLERESP * single = OCSP_resp_get0(bs, 0);
+ const OCSP_CERTID * cid = OCSP_SINGLERESP_get0_id(single);
+ ASN1_INTEGER * res_cert_serial;
+ const BIGNUM * resp_bn;
+ ASN1_OCTET_STRING * res_cert_iNameHash;
+
+
+ (void) OCSP_id_get0_info(&res_cert_iNameHash, NULL, NULL, &res_cert_serial,
+ (OCSP_CERTID *) cid);
+ resp_bn = ASN1_INTEGER_to_BN(res_cert_serial, NULL);
+
+ DEBUG(D_tls)
+ {
+ debug_printf("cert serial: %s\n", BN_bn2hex(cert_bn));
+ debug_printf("resp serial: %s\n", BN_bn2hex(resp_bn));
+ }
+
+ if (BN_cmp(cert_bn, resp_bn) == 0)
+ {
+ DEBUG(D_tls) debug_printf("matched serial for ocsp\n");
+
+ /*XXX TODO: check the rest of the list for duplicate matches.
+ If any, need to also check the Issuer Name hash.
+ Without this, we will provide the wrong status in the case of
+ duplicate id. */
+
+ break;
+ }
+ DEBUG(D_tls) debug_printf("not match serial for ocsp\n");
+ }
+ if (!olist)
+ {
+ DEBUG(D_tls) debug_printf("failed to find match for ocsp\n");
+ return SSL_TLSEXT_ERR_NOACK;
+ }
+ }
+#else
+if (olist->next)
+ {
+ DEBUG(D_tls) debug_printf("OpenSSL version too early to support multi-leaf OCSP\n");
return SSL_TLSEXT_ERR_NOACK;
+ }
+#endif
+/*XXX could we do the i2d earlier, rather than during the callback? */
response_der = NULL;
-response_der_len = i2d_OCSP_RESPONSE(cbinfo->u_ocsp.server.response, /*XXX stack*/
- &response_der);
+response_der_len = i2d_OCSP_RESPONSE(olist->resp, &response_der);
if (response_der_len <= 0)
return SSL_TLSEXT_ERR_NOACK;
-SSL_set_tlsext_status_ocsp_resp(server_ssl, response_der, response_der_len);
+SSL_set_tlsext_status_ocsp_resp(state_server.lib_state.lib_ssl,
+ response_der, response_der_len);
tls_in.ocsp = OCSP_VFIED;
return SSL_TLSEXT_ERR_OK;
}
static int
tls_client_stapling_cb(SSL *s, void *arg)
{
-tls_ext_ctx_cb * cbinfo = arg;
+exim_openssl_state_st * cbinfo = arg;
const unsigned char * p;
int len;
OCSP_RESPONSE * rsp;
OCSP_BASICRESP * bs;
int i;
-DEBUG(D_tls) debug_printf("Received TLS status response (OCSP stapling):");
+DEBUG(D_tls) debug_printf("Received TLS status callback (OCSP stapling):\n");
len = SSL_get_tlsext_status_ocsp_resp(s, &p);
if(!p)
{
/* Expect this when we requested ocsp but got none */
if (cbinfo->u_ocsp.client.verify_required && LOGGING(tls_cipher))
- log_write(0, LOG_MAIN, "Received TLS status callback, null content");
+ log_write(0, LOG_MAIN, "Required TLS certificate status not received");
else
DEBUG(D_tls) debug_printf(" null\n");
return cbinfo->u_ocsp.client.verify_required ? 0 : 1;
}
-if(!(rsp = d2i_OCSP_RESPONSE(NULL, &p, len)))
- {
- tls_out.ocsp = OCSP_FAILED;
+if (!(rsp = d2i_OCSP_RESPONSE(NULL, &p, len)))
+ {
+ tls_out.ocsp = OCSP_FAILED; /*XXX should use tlsp-> to permit concurrent outbound */
if (LOGGING(tls_cipher))
log_write(0, LOG_MAIN, "Received TLS cert status response, parse error");
else
DEBUG(D_tls) debug_printf(" parse error\n");
return 0;
- }
+ }
-if(!(bs = OCSP_response_get1_basic(rsp)))
+if (!(bs = OCSP_response_get1_basic(rsp)))
{
tls_out.ocsp = OCSP_FAILED;
if (LOGGING(tls_cipher))
*/
{
BIO * bp = NULL;
- int status, reason;
- ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd;
+#ifndef EXIM_HAVE_OCSP_RESP_COUNT
+ STACK_OF(OCSP_SINGLERESP) * sresp = bs->tbsResponseData->responses;
+#endif
DEBUG(D_tls) bp = BIO_new_fp(debug_file, BIO_NOCLOSE);
/* DEBUG(D_tls) x509_store_dump_cert_s_names(cbinfo->u_ocsp.client.verify_store); */
if ((i = OCSP_basic_verify(bs, cbinfo->verify_stack,
- cbinfo->u_ocsp.client.verify_store, 0)) <= 0)
- {
- tls_out.ocsp = OCSP_FAILED;
- if (LOGGING(tls_cipher)) log_write(0, LOG_MAIN,
- "Received TLS cert status response, itself unverifiable: %s",
- ERR_reason_error_string(ERR_peek_error()));
- BIO_printf(bp, "OCSP response verify failure\n");
- ERR_print_errors(bp);
- OCSP_RESPONSE_print(bp, rsp, 0);
- goto failed;
- }
+ cbinfo->u_ocsp.client.verify_store, OCSP_NOEXPLICIT)) <= 0)
+ if (ERR_peek_error())
+ {
+ tls_out.ocsp = OCSP_FAILED;
+ if (LOGGING(tls_cipher)) log_write(0, LOG_MAIN,
+ "Received TLS cert status response, itself unverifiable: %s",
+ ERR_reason_error_string(ERR_peek_error()));
+ BIO_printf(bp, "OCSP response verify failure\n");
+ ERR_print_errors(bp);
+ OCSP_RESPONSE_print(bp, rsp, 0);
+ goto failed;
+ }
+ else
+ DEBUG(D_tls) debug_printf("no explicit trust for OCSP signing"
+ " in the root CA certificate; ignoring\n");
- BIO_printf(bp, "OCSP response well-formed and signed OK\n");
+ DEBUG(D_tls) debug_printf("OCSP response well-formed and signed OK\n");
/*XXX So we have a good stapled OCSP status. How do we know
it is for the cert of interest? OpenSSL 1.1.0 has a routine
For now, carry on blindly accepting the resp. */
- {
- OCSP_SINGLERESP * single;
-
+ for (int idx =
#ifdef EXIM_HAVE_OCSP_RESP_COUNT
- if (OCSP_resp_count(bs) != 1)
+ OCSP_resp_count(bs) - 1;
#else
- STACK_OF(OCSP_SINGLERESP) * sresp = bs->tbsResponseData->responses;
- if (sk_OCSP_SINGLERESP_num(sresp) != 1)
+ sk_OCSP_SINGLERESP_num(sresp) - 1;
#endif
- {
- tls_out.ocsp = OCSP_FAILED;
- log_write(0, LOG_MAIN, "OCSP stapling "
- "with multiple responses not handled");
- goto failed;
- }
- single = OCSP_resp_get0(bs, 0);
+ idx >= 0; idx--)
+ {
+ OCSP_SINGLERESP * single = OCSP_resp_get0(bs, idx);
+ int status, reason;
+ ASN1_GENERALIZEDTIME * rev, * thisupd, * nextupd;
+
+ /*XXX so I can see putting a loop in here to handle a rsp with >1 singleresp
+ - but what happens with a GnuTLS-style input?
+
+ we could do with a debug label for each singleresp
+ - it has a certID with a serialNumber, but I see no API to get that
+ */
status = OCSP_single_get0_status(single, &reason, &rev,
&thisupd, &nextupd);
- }
- DEBUG(D_tls) time_print(bp, "This OCSP Update", thisupd);
- DEBUG(D_tls) if(nextupd) time_print(bp, "Next OCSP Update", nextupd);
- if (!OCSP_check_validity(thisupd, nextupd,
- EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE))
- {
- tls_out.ocsp = OCSP_FAILED;
- DEBUG(D_tls) ERR_print_errors(bp);
- log_write(0, LOG_MAIN, "Server OSCP dates invalid");
- }
- else
- {
+ DEBUG(D_tls) time_print(bp, "This OCSP Update", thisupd);
+ DEBUG(D_tls) if(nextupd) time_print(bp, "Next OCSP Update", nextupd);
+ if (!OCSP_check_validity(thisupd, nextupd,
+ EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE))
+ {
+ tls_out.ocsp = OCSP_FAILED;
+ DEBUG(D_tls) ERR_print_errors(bp);
+ log_write(0, LOG_MAIN, "Server OSCP dates invalid");
+ goto failed;
+ }
+
DEBUG(D_tls) BIO_printf(bp, "Certificate status: %s\n",
OCSP_cert_status_str(status));
switch(status)
{
case V_OCSP_CERTSTATUS_GOOD:
- tls_out.ocsp = OCSP_VFIED;
- i = 1;
- goto good;
+ continue; /* the idx loop */
case V_OCSP_CERTSTATUS_REVOKED:
- tls_out.ocsp = OCSP_FAILED;
log_write(0, LOG_MAIN, "Server certificate revoked%s%s",
reason != -1 ? "; reason: " : "",
reason != -1 ? OCSP_crl_reason_str(reason) : "");
DEBUG(D_tls) time_print(bp, "Revocation Time", rev);
break;
default:
- tls_out.ocsp = OCSP_FAILED;
log_write(0, LOG_MAIN,
"Server certificate status unknown, in OCSP stapling");
break;
}
+
+ goto failed;
}
+
+ i = 1;
+ tls_out.ocsp = OCSP_VFIED;
+ goto good;
+
failed:
+ tls_out.ocsp = OCSP_FAILED;
i = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
good:
BIO_free(bp);
/*************************************************
* Initialize for TLS *
*************************************************/
-
/* Called from both server and client code, to do preliminary initialization
of the library. We allocate and return a context structure.
Arguments:
- ctxp returned SSL context
host connected host, if client; NULL if server
- dhparam DH parameter file
- certificate certificate file
- privatekey private key
+ ob transport options block, if client; NULL if server
ocsp_file file of stapling info (server); flag for require ocsp (client)
addr address if client; NULL if server (for some randomness)
- cbp place to put allocated callback context
+ caller_state place to put pointer to allocated state-struct
errstr error string pointer
Returns: OK/DEFER/FAIL
*/
static int
-tls_init(SSL_CTX **ctxp, host_item *host, uschar *dhparam, uschar *certificate,
- uschar *privatekey,
+tls_init(host_item * host, smtp_transport_options_block * ob,
#ifndef DISABLE_OCSP
- uschar *ocsp_file, /*XXX stack, in server*/
+ uschar *ocsp_file,
#endif
- address_item *addr, tls_ext_ctx_cb ** cbp, uschar ** errstr)
+ address_item *addr, exim_openssl_state_st ** caller_state,
+ tls_support * tlsp,
+ uschar ** errstr)
{
SSL_CTX * ctx;
-long init_options;
+exim_openssl_state_st * state;
int rc;
-tls_ext_ctx_cb * cbinfo;
-cbinfo = store_malloc(sizeof(tls_ext_ctx_cb));
-cbinfo->certificate = certificate;
-cbinfo->privatekey = privatekey;
-cbinfo->is_server = host==NULL;
-#ifndef DISABLE_OCSP
-cbinfo->verify_stack = NULL;
-if (!host)
+if (host) /* client */
{
- cbinfo->u_ocsp.server.file = ocsp_file;
- cbinfo->u_ocsp.server.file_expanded = NULL;
- cbinfo->u_ocsp.server.response = NULL;
+ state = store_malloc(sizeof(exim_openssl_state_st));
+ memset(state, 0, sizeof(*state));
+ state->certificate = ob->tls_certificate;
+ state->privatekey = ob->tls_privatekey;
+ state->is_server = FALSE;
+ state->dhparam = NULL;
+ state->lib_state = ob->tls_preload;
+ }
+else /* server */
+ {
+ state = &state_server;
+ state->certificate = tls_certificate;
+ state->privatekey = tls_privatekey;
+ state->is_server = TRUE;
+ state->dhparam = tls_dhparam;
+ state->lib_state = state_server.lib_state;
}
-else
- cbinfo->u_ocsp.client.verify_store = NULL;
-#endif
-cbinfo->dhparam = dhparam;
-cbinfo->server_cipher_list = NULL;
-cbinfo->host = host;
-#ifndef DISABLE_EVENT
-cbinfo->event_action = NULL;
-#endif
-
-#ifdef EXIM_NEED_OPENSSL_INIT
-SSL_load_error_strings(); /* basic set up */
-OpenSSL_add_ssl_algorithms();
-#endif
-#ifdef EXIM_HAVE_SHA256
-/* SHA256 is becoming ever more popular. This makes sure it gets added to the
-list of available digests. */
-EVP_add_digest(EVP_sha256());
-#endif
+state->tlsp = tlsp;
+state->host = host;
-/* Create a context.
-The OpenSSL docs in 1.0.1b have not been updated to clarify TLS variant
-negotiation in the different methods; as far as I can tell, the only
-*_{server,client}_method which allows negotiation is SSLv23, which exists even
-when OpenSSL is built without SSLv2 support.
-By disabling with openssl_options, we can let admins re-enable with the
-existing knob. */
+if (!state->lib_state.pri_string)
+ state->server_cipher_list = NULL;
-#ifdef EXIM_HAVE_OPENSSL_TLS_METHOD
-if (!(ctx = SSL_CTX_new(host ? TLS_client_method() : TLS_server_method())))
-#else
-if (!(ctx = SSL_CTX_new(host ? SSLv23_client_method() : SSLv23_server_method())))
+#ifndef DISABLE_EVENT
+state->event_action = NULL;
#endif
- return tls_error(US"SSL_CTX_new", host, NULL, errstr);
+
+tls_openssl_init();
/* It turns out that we need to seed the random number generator this early in
order to get the full complement of ciphers to work. It took me roughly a day
On systems that have /dev/urandom, SSL may automatically seed itself from
there. Otherwise, we have to make something up as best we can. Double check
-afterwards. */
+afterwards.
-if (!RAND_status())
- {
- randstuff r;
- gettimeofday(&r.tv, NULL);
- r.p = getpid();
-
- RAND_seed(US (&r), sizeof(r));
- RAND_seed(US big_buffer, big_buffer_size);
- if (addr != NULL) RAND_seed(US addr, sizeof(addr));
-
- if (!RAND_status())
- return tls_error(US"RAND_status", host,
- US"unable to seed random number generator", errstr);
- }
-
-/* Set up the information callback, which outputs if debugging is at a suitable
-level. */
+Although we likely called this before, at daemon startup, this is a chance
+to mix in further variable info (time, pid) if needed. */
-DEBUG(D_tls) SSL_CTX_set_info_callback(ctx, (void (*)())info_callback);
-
-/* Automatically re-try reads/writes after renegotiation. */
-(void) SSL_CTX_set_mode(ctx, SSL_MODE_AUTO_RETRY);
+if (!lib_rand_init(addr))
+ return tls_error(US"RAND_status", host,
+ US"unable to seed random number generator", errstr);
/* Apply administrator-supplied work-arounds.
Historically we applied just one requested option,
No OpenSSL version number checks: the options we accept depend upon the
availability of the option value macros from OpenSSL. */
-if (!tls_openssl_options_parse(openssl_options, &init_options))
- return tls_error(US"openssl_options parsing failed", host, NULL, errstr);
+if (!init_options)
+ if (!tls_openssl_options_parse(openssl_options, &init_options))
+ return tls_error(US"openssl_options parsing failed", host, NULL, errstr);
+
+/* Create a context.
+The OpenSSL docs in 1.0.1b have not been updated to clarify TLS variant
+negotiation in the different methods; as far as I can tell, the only
+*_{server,client}_method which allows negotiation is SSLv23, which exists even
+when OpenSSL is built without SSLv2 support.
+By disabling with openssl_options, we can let admins re-enable with the
+existing knob. */
+
+if (!(ctx = state->lib_state.lib_ctx))
+ {
+ if ((rc = lib_ctx_new(&ctx, host, errstr)) != OK)
+ return rc;
+ state->lib_state.lib_ctx = ctx;
+ }
+#ifndef DISABLE_TLS_RESUME
+tlsp->resumption = RESUME_SUPPORTED;
+#endif
if (init_options)
{
+#ifndef DISABLE_TLS_RESUME
+ /* Should the server offer session resumption? */
+ if (!host && verify_check_host(&tls_resumption_hosts) == OK)
+ {
+ DEBUG(D_tls) debug_printf("tls_resumption_hosts overrides openssl_options\n");
+ init_options &= ~SSL_OP_NO_TICKET;
+ tlsp->resumption |= RESUME_SERVER_TICKET; /* server will give ticket on request */
+ tlsp->host_resumable = TRUE;
+ }
+#endif
+
DEBUG(D_tls) debug_printf("setting SSL CTX options: %#lx\n", init_options);
if (!(SSL_CTX_set_options(ctx, init_options)))
return tls_error(string_sprintf(
/* Initialize with DH parameters if supplied */
/* Initialize ECDH temp key parameter selection */
-if ( !init_dh(ctx, dhparam, host, errstr)
- || !init_ecdh(ctx, host, errstr)
- )
- return DEFER;
+if (state->lib_state.dh)
+ { DEBUG(D_tls) debug_printf("TLS: DH params were preloaded\n"); }
+else
+ if (!init_dh(ctx, state->dhparam, host, errstr)) return DEFER;
+
+if (state->lib_state.ecdh)
+ { DEBUG(D_tls) debug_printf("TLS: ECDH curve was preloaded\n"); }
+else
+ if (!init_ecdh(ctx, host, errstr)) return DEFER;
/* Set up certificate and key (and perhaps OCSP info) */
-if ((rc = tls_expand_session_files(ctx, cbinfo, errstr)) != OK)
- return rc;
+if (state->lib_state.conn_certs)
+ {
+ DEBUG(D_tls)
+ debug_printf("TLS: %s certs were preloaded\n", host ? "client":"server");
+ }
+else
+ {
+#ifndef DISABLE_OCSP
+ if (!host)
+ {
+ state->u_ocsp.server.file = ocsp_file;
+ state->u_ocsp.server.file_expanded = NULL;
+ state->u_ocsp.server.olist = NULL;
+ }
+#endif
+ if ((rc = tls_expand_session_files(ctx, state, errstr)) != OK) return rc;
+ }
/* If we need to handle SNI or OCSP, do so */
#ifdef EXIM_HAVE_OPENSSL_TLSEXT
# ifndef DISABLE_OCSP
- if (!(cbinfo->verify_stack = sk_X509_new_null()))
+ if (!(state->verify_stack = sk_X509_new_null()))
{
DEBUG(D_tls) debug_printf("failed to create stack for stapling verify\n");
return FAIL;
if (!host) /* server */
{
# ifndef DISABLE_OCSP
- /* We check u_ocsp.server.file, not server.response, because we care about if
+ /* We check u_ocsp.server.file, not server.olist, because we care about if
the option exists, not what the current expansion might be, as SNI might
change the certificate and OCSP file in use between now and the time the
callback is invoked. */
- if (cbinfo->u_ocsp.server.file)
+ if (state->u_ocsp.server.file)
{
SSL_CTX_set_tlsext_status_cb(ctx, tls_server_stapling_cb);
- SSL_CTX_set_tlsext_status_arg(ctx, cbinfo);
+ SSL_CTX_set_tlsext_status_arg(ctx, state);
}
# endif
/* We always do this, so that $tls_sni is available even if not used in
tls_certificate */
SSL_CTX_set_tlsext_servername_callback(ctx, tls_servername_cb);
- SSL_CTX_set_tlsext_servername_arg(ctx, cbinfo);
+ SSL_CTX_set_tlsext_servername_arg(ctx, state);
+
+# ifdef EXIM_HAVE_ALPN
+ if (tls_alpn && *tls_alpn)
+ {
+ uschar * exp_alpn;
+ if ( expand_check(tls_alpn, US"tls_alpn", &exp_alpn, errstr)
+ && *exp_alpn && !isblank(*exp_alpn))
+ {
+ tls_alpn = exp_alpn; /* subprocess so ok to overwrite */
+ SSL_CTX_set_alpn_select_cb(ctx, tls_server_alpn_cb, state);
+ }
+ else
+ tls_alpn = NULL;
+ }
+# endif
}
# ifndef DISABLE_OCSP
else /* client */
if(ocsp_file) /* wanting stapling */
{
- if (!(cbinfo->u_ocsp.client.verify_store = X509_STORE_new()))
+ if (!(state->u_ocsp.client.verify_store = X509_STORE_new()))
{
DEBUG(D_tls) debug_printf("failed to create store for stapling verify\n");
return FAIL;
}
SSL_CTX_set_tlsext_status_cb(ctx, tls_client_stapling_cb);
- SSL_CTX_set_tlsext_status_arg(ctx, cbinfo);
+ SSL_CTX_set_tlsext_status_arg(ctx, state);
}
# endif
#endif
-cbinfo->verify_cert_hostnames = NULL;
+state->verify_cert_hostnames = NULL;
#ifdef EXIM_HAVE_EPHEM_RSA_KEX
/* Set up the RSA callback */
SSL_CTX_set_tmp_rsa_callback(ctx, rsa_callback);
#endif
-/* Finally, set the timeout, and we are done */
+/* Finally, set the session cache timeout, and we are done.
+The period appears to be also used for (server-generated) session tickets */
SSL_CTX_set_timeout(ctx, ssl_session_timeout);
DEBUG(D_tls) debug_printf("Initialized TLS\n");
-*cbp = cbinfo;
-*ctxp = ctx;
+*caller_state = state;
return OK;
}
/*
Argument: pointer to an SSL structure for the connection
- buffer to use for answer
- size of buffer
pointer to number of bits for cipher
-Returns: nothing
+Returns: pointer to allocated string in perm-pool
*/
-static void
-construct_cipher_name(SSL *ssl, uschar *cipherbuf, int bsize, int *bits)
+static uschar *
+construct_cipher_name(SSL * ssl, const uschar * ver, int * bits)
{
+int pool = store_pool;
/* With OpenSSL 1.0.0a, 'c' needs to be const but the documentation doesn't
yet reflect that. It should be a safe change anyway, even 0.9.8 versions have
the accessor functions use const in the prototype. */
-const uschar * ver = CUS SSL_get_version(ssl);
const SSL_CIPHER * c = (const SSL_CIPHER *) SSL_get_current_cipher(ssl);
+uschar * s;
SSL_CIPHER_get_bits(c, bits);
-string_format(cipherbuf, bsize, "%s:%s:%u", ver,
- SSL_CIPHER_get_name(c), *bits);
+store_pool = POOL_PERM;
+s = string_sprintf("%s:%s:%u", ver, SSL_CIPHER_get_name(c), *bits);
+store_pool = pool;
+DEBUG(D_tls) debug_printf("Cipher: %s\n", s);
+return s;
+}
+
+
+/* Get IETF-standard name for ciphersuite.
+Argument: pointer to an SSL structure for the connection
+Returns: pointer to string
+*/
+
+static const uschar *
+cipher_stdname_ssl(SSL * ssl)
+{
+#ifdef EXIM_HAVE_OPENSSL_CIPHER_STD_NAME
+return CUS SSL_CIPHER_standard_name(SSL_get_current_cipher(ssl));
+#else
+ushort id = 0xffff & SSL_CIPHER_get_id(SSL_get_current_cipher(ssl));
+return cipher_stdname(id >> 8, id & 0xff);
+#endif
+}
+
-DEBUG(D_tls) debug_printf("Cipher: %s\n", cipherbuf);
+static const uschar *
+tlsver_name(SSL * ssl)
+{
+uschar * s, * p;
+int pool = store_pool;
+
+store_pool = POOL_PERM;
+s = string_copy(US SSL_get_version(ssl));
+store_pool = pool;
+if ((p = Ustrchr(s, 'v'))) /* TLSv1.2 -> TLS1.2 */
+ for (;; p++) if (!(*p = p[1])) break;
+return CUS s;
}
{ DEBUG(D_tls) debug_printf("X509_NAME_oneline() error\n"); }
else
{
- peerdn[siz-1] = '\0';
- tlsp->peerdn = peerdn; /*XXX a static buffer... */
+ int oldpool = store_pool;
+
+ peerdn[siz-1] = '\0'; /* paranoia */
+ store_pool = POOL_PERM;
+ tlsp->peerdn = string_copy(peerdn);
+ store_pool = oldpool;
+
+ /* We used to set CV in the cert-verify callbacks (either plain or dane)
+ but they don't get called on session-resumption. So use the official
+ interface, which uses the resumed value. Unfortunately this claims verified
+ when it actually failed but we're in try-verify mode, due to us wanting the
+ knowlege that it failed so needing to have the callback and forcing a
+ permissive return. If we don't force it, the TLS startup is failed.
+ The extra bit of information is set in verify_override in the cb, stashed
+ for resumption next to the TLS session, and used here. */
+
+ if (!tlsp->verify_override)
+ tlsp->certificate_verified =
+#ifdef SUPPORT_DANE
+ tlsp->dane_verified ||
+#endif
+ SSL_get_verify_result(ssl) == X509_V_OK;
}
}
/* Load certs from file, return TRUE on success */
static BOOL
-chain_from_pem_file(const uschar * file, STACK_OF(X509) * verify_stack)
+chain_from_pem_file(const uschar * file, STACK_OF(X509) ** vp)
{
BIO * bp;
-X509 * x;
+STACK_OF(X509) * verify_stack = *vp;
-while (sk_X509_num(verify_stack) > 0)
- X509_free(sk_X509_pop(verify_stack));
+if (verify_stack)
+ while (sk_X509_num(verify_stack) > 0)
+ X509_free(sk_X509_pop(verify_stack));
+else
+ verify_stack = sk_X509_new_null();
if (!(bp = BIO_new_file(CS file, "r"))) return FALSE;
-while ((x = PEM_read_bio_X509(bp, NULL, 0, NULL)))
+for (X509 * x; x = PEM_read_bio_X509(bp, NULL, 0, NULL); )
sk_X509_push(verify_stack, x);
BIO_free(bp);
+*vp = verify_stack;
return TRUE;
}
#endif
Arguments:
sctx SSL_CTX* to initialise
- certs certs file or NULL
+ certs certs file, expanded
crl CRL file or NULL
host NULL in a server; the remote host in a client
- optional TRUE if called from a server for a host in tls_try_verify_hosts;
- otherwise passed as FALSE
- cert_vfy_cb Callback function for certificate verification
errstr error string pointer
Returns: OK/DEFER/FAIL
*/
static int
-setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host, BOOL optional,
- int (*cert_vfy_cb)(int, X509_STORE_CTX *), uschar ** errstr)
+setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host,
+ uschar ** errstr)
{
uschar *expcerts, *expcrl;
if (!SSL_CTX_set_default_verify_paths(sctx))
return tls_error(US"SSL_CTX_set_default_verify_paths", host, NULL, errstr);
- if (Ustrcmp(expcerts, "system") != 0)
+ if (Ustrcmp(expcerts, "system") != 0 && Ustrncmp(expcerts, "system,", 7) != 0)
{
struct stat statbuf;
{ file = NULL; dir = expcerts; }
else
{
+ STACK_OF(X509) * verify_stack =
+#ifndef DISABLE_OCSP
+ !host ? state_server.verify_stack :
+#endif
+ NULL;
+ STACK_OF(X509) ** vp = &verify_stack;
+
file = expcerts; dir = NULL;
#ifndef DISABLE_OCSP
/* In the server if we will be offering an OCSP proof, load chain from
file for verifying the OCSP proof at load time. */
+/*XXX Glitch! The file here is tls_verify_certs: the chain for verifying the client cert.
+This is inconsistent with the need to verify the OCSP proof of the server cert.
+*/
if ( !host
&& statbuf.st_size > 0
- && server_static_cbinfo->u_ocsp.server.file
- && !chain_from_pem_file(file, server_static_cbinfo->verify_stack)
+ && state_server.u_ocsp.server.file
+ && !chain_from_pem_file(file, vp)
)
{
log_write(0, LOG_MAIN|LOG_PANIC,
#endif
}
- /* If a certificate file is empty, the next function fails with an
+ /* If a certificate file is empty, the load function fails with an
unhelpful error message. If we skip it, we get the correct behaviour (no
certificates are recognized, but the error message is still misleading (it
says no certificate was supplied). But this is better. */
if ( (!file || statbuf.st_size > 0)
&& !SSL_CTX_load_verify_locations(sctx, CS file, CS dir))
- return tls_error(US"SSL_CTX_load_verify_locations", host, NULL, errstr);
-
- /* Load the list of CAs for which we will accept certs, for sending
- to the client. This is only for the one-file tls_verify_certificates
- variant.
- If a list isn't loaded into the server, but
- some verify locations are set, the server end appears to make
- a wildcard request for client certs.
+ return tls_error(US"SSL_CTX_load_verify_locations",
+ host, NULL, errstr);
+
+ /* On the server load the list of CAs for which we will accept certs, for
+ sending to the client. This is only for the one-file
+ tls_verify_certificates variant.
+ If a list isn't loaded into the server, but some verify locations are set,
+ the server end appears to make a wildcard request for client certs.
Meanwhile, the client library as default behaviour *ignores* the list
we send over the wire - see man SSL_CTX_set_client_cert_cb.
Because of this, and that the dir variant is likely only used for
- the public-CA bundle (not for a private CA), not worth fixing.
- */
+ the public-CA bundle (not for a private CA), not worth fixing. */
+
if (file)
{
STACK_OF(X509_NAME) * names = SSL_load_client_CA_file(CS file);
+ int i = sk_X509_NAME_num(names);
- SSL_CTX_set_client_CA_list(sctx, names);
- DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n",
- sk_X509_NAME_num(names));
+ if (!host) SSL_CTX_set_client_CA_list(sctx, names);
+ DEBUG(D_tls) debug_printf("Added %d additional certificate authorit%s\n",
+ i, i>1 ? "ies":"y");
}
+ else
+ DEBUG(D_tls)
+ debug_printf("Added dir for additional certificate authorities\n");
}
}
}
#endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
-
- /* If verification is optional, don't fail if no certificate */
-
- SSL_CTX_set_verify(sctx,
- SSL_VERIFY_PEER | (optional ? 0 : SSL_VERIFY_FAIL_IF_NO_PEER_CERT),
- cert_vfy_cb);
}
return OK;
/*************************************************
* Start a TLS session in a server *
*************************************************/
-
/* This is called when Exim is running as a server, after having received
the STARTTLS command. It must respond to that command, and then negotiate
a TLS session.
Arguments:
- require_ciphers allowed ciphers
errstr pointer to error message
Returns: OK on success
*/
int
-tls_server_start(const uschar * require_ciphers, uschar ** errstr)
+tls_server_start(uschar ** errstr)
{
int rc;
uschar * expciphers;
-tls_ext_ctx_cb * cbinfo;
+exim_openssl_state_st * dummy_statep;
+SSL_CTX * ctx;
+SSL * ssl;
static uschar peerdn[256];
-static uschar cipherbuf[256];
/* Check for previous activation */
/* Initialize the SSL library. If it fails, it will already have logged
the error. */
-rc = tls_init(&server_ctx, NULL, tls_dhparam, tls_certificate, tls_privatekey,
+rc = tls_init(NULL, NULL,
#ifndef DISABLE_OCSP
- tls_ocsp_file, /*XXX stack*/
+ tls_ocsp_file,
#endif
- NULL, &server_static_cbinfo, errstr);
+ NULL, &dummy_statep, &tls_in, errstr);
if (rc != OK) return rc;
-cbinfo = server_static_cbinfo;
-
-if (!expand_check(require_ciphers, US"tls_require_ciphers", &expciphers, errstr))
- return FAIL;
+ctx = state_server.lib_state.lib_ctx;
/* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they
were historically separated by underscores. So that I can use either form in my
TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256
*/
-if (expciphers)
+if (state_server.lib_state.pri_string)
+ { DEBUG(D_tls) debug_printf("TLS: cipher list was preloaded\n"); }
+else
{
- uschar * s = expciphers;
- while (*s != 0) { if (*s == '_') *s = '-'; s++; }
- DEBUG(D_tls) debug_printf("required ciphers: %s\n", expciphers);
- if (!SSL_CTX_set_cipher_list(server_ctx, CS expciphers))
- return tls_error(US"SSL_CTX_set_cipher_list", NULL, NULL, errstr);
- cbinfo->server_cipher_list = expciphers;
+ if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers, errstr))
+ return FAIL;
+
+ if ( expciphers
+ && (rc = server_load_ciphers(ctx, &state_server, expciphers, errstr)) != OK)
+ return rc;
}
/* If this is a host for which certificate verification is mandatory or
server_verify_callback_called = FALSE;
if (verify_check_host(&tls_verify_hosts) == OK)
- {
- rc = setup_certs(server_ctx, tls_verify_certificates, tls_crl, NULL,
- FALSE, verify_callback_server, errstr);
- if (rc != OK) return rc;
server_verify_optional = FALSE;
- }
else if (verify_check_host(&tls_try_verify_hosts) == OK)
- {
- rc = setup_certs(server_ctx, tls_verify_certificates, tls_crl, NULL,
- TRUE, verify_callback_server, errstr);
- if (rc != OK) return rc;
server_verify_optional = TRUE;
+else
+ goto skip_certs;
+
+ {
+ uschar * expcerts;
+ if (!expand_check(tls_verify_certificates, US"tls_verify_certificates",
+ &expcerts, errstr))
+ return DEFER;
+ DEBUG(D_tls) debug_printf("tls_verify_certificates: %s\n", expcerts);
+
+ if (state_server.lib_state.cabundle)
+ { DEBUG(D_tls) debug_printf("TLS: CA bundle for server was preloaded\n"); }
+ else
+ if ((rc = setup_certs(ctx, expcerts, tls_crl, NULL, errstr)) != OK)
+ return rc;
+
+ if (expcerts && *expcerts)
+ setup_cert_verify(ctx, server_verify_optional, verify_callback_server);
}
+skip_certs: ;
+
+#ifndef DISABLE_TLS_RESUME
+SSL_CTX_set_tlsext_ticket_key_cb(ctx, ticket_key_callback);
+/* despite working, appears to always return failure, so ignoring */
+#endif
+#ifdef OPENSSL_HAVE_NUM_TICKETS
+# ifndef DISABLE_TLS_RESUME
+SSL_CTX_set_num_tickets(ctx, tls_in.host_resumable ? 1 : 0);
+# else
+SSL_CTX_set_num_tickets(ctx, 0); /* send no TLS1.3 stateful-tickets */
+# endif
+#endif
+
/* Prepare for new connection */
-if (!(server_ssl = SSL_new(server_ctx)))
+if (!(ssl = SSL_new(ctx)))
return tls_error(US"SSL_new", NULL, NULL, errstr);
+state_server.lib_state.lib_ssl = ssl;
/* Warning: we used to SSL_clear(ssl) here, it was removed.
*
the response. Other smtp_printf() calls do not need it, because in non-TLS
mode, the fflush() happens when smtp_getc() is called. */
-SSL_set_session_id_context(server_ssl, sid_ctx, Ustrlen(sid_ctx));
+SSL_set_session_id_context(ssl, sid_ctx, Ustrlen(sid_ctx));
if (!tls_in.on_connect)
{
smtp_printf("220 TLS go ahead\r\n", FALSE);
/* Now negotiate the TLS session. We put our own timer on it, since it seems
that the OpenSSL library doesn't. */
-SSL_set_wfd(server_ssl, fileno(smtp_out));
-SSL_set_rfd(server_ssl, fileno(smtp_in));
-SSL_set_accept_state(server_ssl);
+SSL_set_wfd(ssl, fileno(smtp_out));
+SSL_set_rfd(ssl, fileno(smtp_in));
+SSL_set_accept_state(ssl);
DEBUG(D_tls) debug_printf("Calling SSL_accept\n");
+ERR_clear_error();
sigalrm_seen = FALSE;
if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
-rc = SSL_accept(server_ssl);
+rc = SSL_accept(ssl);
ALARM_CLR(0);
if (rc <= 0)
{
- (void) tls_error(US"SSL_accept", NULL, sigalrm_seen ? US"timed out" : NULL, errstr);
- return FAIL;
+ int error = SSL_get_error(ssl, rc);
+ switch(error)
+ {
+ case SSL_ERROR_NONE:
+ break;
+
+ case SSL_ERROR_ZERO_RETURN:
+ DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n");
+ (void) tls_error(US"SSL_accept", NULL, sigalrm_seen ? US"timed out" : NULL, errstr);
+
+ if (SSL_get_shutdown(ssl) == SSL_RECEIVED_SHUTDOWN)
+ SSL_shutdown(ssl);
+
+ tls_close(NULL, TLS_NO_SHUTDOWN);
+ return FAIL;
+
+ /* Handle genuine errors */
+ case SSL_ERROR_SSL:
+ {
+ uschar * s = NULL;
+ int r = ERR_GET_REASON(ERR_peek_error());
+ if ( r == SSL_R_WRONG_VERSION_NUMBER
+#ifdef SSL_R_VERSION_TOO_LOW
+ || r == SSL_R_VERSION_TOO_LOW
+#endif
+ || r == SSL_R_UNKNOWN_PROTOCOL || r == SSL_R_UNSUPPORTED_PROTOCOL)
+ s = string_sprintf("%s (%s)", s, SSL_get_version(ssl));
+ (void) tls_error(US"SSL_accept", NULL, sigalrm_seen ? US"timed out" : s, errstr);
+ return FAIL;
+ }
+
+ default:
+ DEBUG(D_tls) debug_printf("Got SSL error %d\n", error);
+ if (error == SSL_ERROR_SYSCALL)
+ {
+ if (!errno)
+ {
+ *errstr = US"SSL_accept: TCP connection closed by peer";
+ return FAIL;
+ }
+ DEBUG(D_tls) debug_printf(" - syscall %s\n", strerror(errno));
+ }
+ (void) tls_error(US"SSL_accept", NULL,
+ sigalrm_seen ? US"timed out"
+ : ERR_peek_error() ? NULL : string_sprintf("ret %d", error),
+ errstr);
+ return FAIL;
+ }
}
DEBUG(D_tls) debug_printf("SSL_accept was successful\n");
ERR_clear_error(); /* Even success can leave errors in the stack. Seen with
- anon-authentication ciphersuite negociated. */
+ anon-authentication ciphersuite negotiated. */
+
+#ifndef DISABLE_TLS_RESUME
+if (SSL_session_reused(ssl))
+ {
+ tls_in.resumption |= RESUME_USED;
+ DEBUG(D_tls) debug_printf("Session reused\n");
+ }
+#endif
+
+#ifdef EXIM_HAVE_ALPN
+/* If require-alpn, check server_seen_alpn here. Else abort TLS */
+if (!tls_alpn || !*tls_alpn)
+ { DEBUG(D_tls) debug_printf("TLS: was not watching for ALPN\n"); }
+else if (!server_seen_alpn)
+ if (verify_check_host(&hosts_require_alpn) == OK)
+ {
+ /* We'd like to send a definitive Alert but OpenSSL provides no facility */
+ SSL_shutdown(ssl);
+ tls_error(US"handshake", NULL, US"ALPN required but not negotiated", errstr);
+ return FAIL;
+ }
+ else
+ { DEBUG(D_tls) debug_printf("TLS: no ALPN presented in handshake\n"); }
+else DEBUG(D_tls)
+ {
+ const uschar * name;
+ unsigned len;
+ SSL_get0_alpn_selected(ssl, &name, &len);
+ if (len && name)
+ debug_printf("ALPN negotiated: '%.*s'\n", (int)*name, name+1);
+ else
+ debug_printf("ALPN: no protocol negotiated\n");
+ }
+#endif
+
-/* TLS has been set up. Adjust the input functions to read via TLS,
-and initialize things. */
+/* TLS has been set up. Record data for the connection,
+adjust the input functions to read via TLS, and initialize things. */
-peer_cert(server_ssl, &tls_in, peerdn, sizeof(peerdn));
+#ifdef SSL_get_extms_support
+tls_in.ext_master_secret = SSL_get_extms_support(ssl) == 1;
+#endif
+peer_cert(ssl, &tls_in, peerdn, sizeof(peerdn));
-construct_cipher_name(server_ssl, cipherbuf, sizeof(cipherbuf), &tls_in.bits);
-tls_in.cipher = cipherbuf;
+tls_in.ver = tlsver_name(ssl);
+tls_in.cipher = construct_cipher_name(ssl, tls_in.ver, &tls_in.bits);
+tls_in.cipher_stdname = cipher_stdname_ssl(ssl);
DEBUG(D_tls)
{
uschar buf[2048];
- if (SSL_get_shared_ciphers(server_ssl, CS buf, sizeof(buf)) != NULL)
+ if (SSL_get_shared_ciphers(ssl, CS buf, sizeof(buf)))
debug_printf("Shared ciphers: %s\n", buf);
+
+#ifdef EXIM_HAVE_OPENSSL_KEYLOG
+ {
+ BIO * bp = BIO_new_fp(debug_file, BIO_NOCLOSE);
+ SSL_SESSION_print_keylog(bp, SSL_get_session(ssl));
+ BIO_free(bp);
+ }
+#endif
+
+#ifdef EXIM_HAVE_SESSION_TICKET
+ {
+ SSL_SESSION * ss = SSL_get_session(ssl);
+ if (SSL_SESSION_has_ticket(ss)) /* 1.1.0 */
+ debug_printf("The session has a ticket, life %lu seconds\n",
+ SSL_SESSION_get_ticket_lifetime_hint(ss));
+ }
+#endif
+ }
+
+/* Record the certificate we presented */
+ {
+ X509 * crt = SSL_get_certificate(ssl);
+ tls_in.ourcert = crt ? X509_dup(crt) : NULL;
}
-/* Record the certificate we presented */
+/* Channel-binding info for authenticators
+See description in https://paquier.xyz/postgresql-2/channel-binding-openssl/ */
{
- X509 * crt = SSL_get_certificate(server_ssl);
- tls_in.ourcert = crt ? X509_dup(crt) : NULL;
+ uschar c, * s;
+ size_t len = SSL_get_peer_finished(ssl, &c, 0);
+ int old_pool = store_pool;
+
+ SSL_get_peer_finished(ssl, s = store_get((int)len, FALSE), len);
+ store_pool = POOL_PERM;
+ tls_in.channelbinding = b64encode_taint(CUS s, (int)len, FALSE);
+ store_pool = old_pool;
+ DEBUG(D_tls) debug_printf("Have channel bindings cached for possible auth usage %p\n", tls_in.channelbinding);
}
/* Only used by the server-side tls (tls_in), including tls_getc.
receive_getc = tls_getc;
receive_getbuf = tls_getbuf;
receive_get_cache = tls_get_cache;
+receive_hasc = tls_hasc;
receive_ungetc = tls_ungetc;
receive_feof = tls_feof;
receive_ferror = tls_ferror;
static int
tls_client_basic_ctx_init(SSL_CTX * ctx,
- host_item * host, smtp_transport_options_block * ob, tls_ext_ctx_cb * cbinfo,
+ host_item * host, smtp_transport_options_block * ob, exim_openssl_state_st * state,
uschar ** errstr)
{
int rc;
-/* stick to the old behaviour for compatibility if tls_verify_certificates is
- set but both tls_verify_hosts and tls_try_verify_hosts is not set. Check only
- the specified host patterns if one of them is defined */
-if ( ( !ob->tls_verify_hosts
- && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts)
+/* Back-compatible old behaviour if tls_verify_certificates is set but both
+tls_verify_hosts and tls_try_verify_hosts are not set. Check only the specified
+host patterns if one of them is set with content. */
+
+if ( ( ( !ob->tls_verify_hosts || !ob->tls_verify_hosts
+ || Ustrcmp(ob->tls_try_verify_hosts, ":") == 0
+ )
+ && ( !ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts
+ || Ustrcmp(ob->tls_try_verify_hosts, ":") == 0
+ )
)
|| verify_check_given_host(CUSS &ob->tls_verify_hosts, host) == OK
)
else
return OK;
-if ((rc = setup_certs(ctx, ob->tls_verify_certificates,
- ob->tls_crl, host, client_verify_optional, verify_callback_client,
- errstr)) != OK)
- return rc;
+ {
+ uschar * expcerts;
+ if (!expand_check(ob->tls_verify_certificates, US"tls_verify_certificates",
+ &expcerts, errstr))
+ return DEFER;
+ DEBUG(D_tls) debug_printf("tls_verify_certificates: %s\n", expcerts);
+
+ if (state->lib_state.cabundle)
+ { DEBUG(D_tls) debug_printf("TLS: CA bundle was preloaded\n"); }
+ else
+ if ((rc = setup_certs(ctx, expcerts, ob->tls_crl, host, errstr)) != OK)
+ return rc;
+
+ if (expcerts && *expcerts)
+ setup_cert_verify(ctx, client_verify_optional, verify_callback_client);
+ }
if (verify_check_given_host(CUSS &ob->tls_verify_cert_hostnames, host) == OK)
{
- cbinfo->verify_cert_hostnames =
+ state->verify_cert_hostnames =
#ifdef SUPPORT_I18N
- string_domain_utf8_to_alabel(host->name, NULL);
+ string_domain_utf8_to_alabel(host->certname, NULL);
#else
- host->name;
+ host->certname;
#endif
DEBUG(D_tls) debug_printf("Cert hostname to check: \"%s\"\n",
- cbinfo->verify_cert_hostnames);
+ state->verify_cert_hostnames);
}
return OK;
}
static int
dane_tlsa_load(SSL * ssl, host_item * host, dns_answer * dnsa, uschar ** errstr)
{
-dns_record * rr;
dns_scan dnss;
const char * hostnames[2] = { CS host->name, NULL };
int found = 0;
if (DANESSL_init(ssl, NULL, hostnames) != 1)
return tls_error(US"hostnames load", host, NULL, errstr);
-for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS);
- rr;
+for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
) if (rr->type == T_TLSA && rr->size > 3)
{
+#ifndef DISABLE_TLS_RESUME
+/* On the client, get any stashed session for the given IP from hints db
+and apply it to the ssl-connection for attempted resumption. */
+
+static void
+tls_retrieve_session(tls_support * tlsp, SSL * ssl, const uschar * key)
+{
+tlsp->resumption |= RESUME_SUPPORTED;
+if (tlsp->host_resumable)
+ {
+ dbdata_tls_session * dt;
+ int len;
+ open_db dbblock, * dbm_file;
+
+ tlsp->resumption |= RESUME_CLIENT_REQUESTED;
+ DEBUG(D_tls) debug_printf("checking for resumable session for %s\n", key);
+ if ((dbm_file = dbfn_open(US"tls", O_RDWR, &dbblock, FALSE, FALSE)))
+ {
+ /* key for the db is the IP */
+ if ((dt = dbfn_read_with_length(dbm_file, key, &len)))
+ {
+ SSL_SESSION * ss = NULL;
+ const uschar * sess_asn1 = dt->session;
+
+ len -= sizeof(dbdata_tls_session);
+ if (!(d2i_SSL_SESSION(&ss, &sess_asn1, (long)len)))
+ {
+ DEBUG(D_tls)
+ {
+ ERR_error_string_n(ERR_get_error(),
+ ssl_errstring, sizeof(ssl_errstring));
+ debug_printf("decoding session: %s\n", ssl_errstring);
+ }
+ }
+ else
+ {
+ unsigned long lifetime =
+#ifdef EXIM_HAVE_SESSION_TICKET
+ SSL_SESSION_get_ticket_lifetime_hint(ss);
+#else /* Use, fairly arbitrilarily, what we as server would */
+ f.running_in_test_harness ? 6 : ssl_session_timeout;
+#endif
+ if (lifetime + dt->time_stamp < time(NULL))
+ {
+ DEBUG(D_tls) debug_printf("session expired\n");
+ dbfn_delete(dbm_file, key);
+ }
+ else if (!SSL_set_session(ssl, ss))
+ {
+ DEBUG(D_tls)
+ {
+ ERR_error_string_n(ERR_get_error(),
+ ssl_errstring, sizeof(ssl_errstring));
+ debug_printf("applying session to ssl: %s\n", ssl_errstring);
+ }
+ }
+ else
+ {
+ DEBUG(D_tls) debug_printf("good session\n");
+ tlsp->resumption |= RESUME_CLIENT_SUGGESTED;
+ tlsp->verify_override = dt->verify_override;
+ tlsp->ocsp = dt->ocsp;
+ }
+ }
+ }
+ else
+ DEBUG(D_tls) debug_printf("no session record\n");
+ dbfn_close(dbm_file);
+ }
+ }
+}
+
+
+/* On the client, save the session for later resumption */
+
+static int
+tls_save_session_cb(SSL * ssl, SSL_SESSION * ss)
+{
+exim_openssl_state_st * cbinfo = SSL_get_ex_data(ssl, tls_exdata_idx);
+tls_support * tlsp;
+
+DEBUG(D_tls) debug_printf("tls_save_session_cb\n");
+
+if (!cbinfo || !(tlsp = cbinfo->tlsp)->host_resumable) return 0;
+
+# ifdef OPENSSL_HAVE_NUM_TICKETS
+if (SSL_SESSION_is_resumable(ss)) /* 1.1.1 */
+# endif
+ {
+ int len = i2d_SSL_SESSION(ss, NULL);
+ int dlen = sizeof(dbdata_tls_session) + len;
+ dbdata_tls_session * dt = store_get(dlen, TRUE);
+ uschar * s = dt->session;
+ open_db dbblock, * dbm_file;
+
+ DEBUG(D_tls) debug_printf("session is resumable\n");
+ tlsp->resumption |= RESUME_SERVER_TICKET; /* server gave us a ticket */
+
+ dt->verify_override = tlsp->verify_override;
+ dt->ocsp = tlsp->ocsp;
+ (void) i2d_SSL_SESSION(ss, &s); /* s gets bumped to end */
+
+ if ((dbm_file = dbfn_open(US"tls", O_RDWR, &dbblock, FALSE, FALSE)))
+ {
+ const uschar * key = cbinfo->host->address;
+ dbfn_delete(dbm_file, key);
+ dbfn_write(dbm_file, key, dt, dlen);
+ dbfn_close(dbm_file);
+ DEBUG(D_tls) debug_printf("wrote session (len %u) to db\n",
+ (unsigned)dlen);
+ }
+ }
+return 1;
+}
+
+
+static void
+tls_client_ctx_resume_prehandshake(
+ exim_openssl_client_tls_ctx * exim_client_ctx, tls_support * tlsp,
+ smtp_transport_options_block * ob, host_item * host)
+{
+/* Should the client request a session resumption ticket? */
+if (verify_check_given_host(CUSS &ob->tls_resumption_hosts, host) == OK)
+ {
+ tlsp->host_resumable = TRUE;
+
+ SSL_CTX_set_session_cache_mode(exim_client_ctx->ctx,
+ SSL_SESS_CACHE_CLIENT
+ | SSL_SESS_CACHE_NO_INTERNAL | SSL_SESS_CACHE_NO_AUTO_CLEAR);
+ SSL_CTX_sess_set_new_cb(exim_client_ctx->ctx, tls_save_session_cb);
+ }
+}
+
+static BOOL
+tls_client_ssl_resume_prehandshake(SSL * ssl, tls_support * tlsp,
+ host_item * host, uschar ** errstr)
+{
+if (tlsp->host_resumable)
+ {
+ DEBUG(D_tls)
+ debug_printf("tls_resumption_hosts overrides openssl_options, enabling tickets\n");
+ SSL_clear_options(ssl, SSL_OP_NO_TICKET);
+
+ tls_exdata_idx = SSL_get_ex_new_index(0, 0, 0, 0, 0);
+ if (!SSL_set_ex_data(ssl, tls_exdata_idx, client_static_state))
+ {
+ tls_error(US"set ex_data", host, NULL, errstr);
+ return FALSE;
+ }
+ debug_printf("tls_exdata_idx %d cbinfo %p\n", tls_exdata_idx, client_static_state);
+ }
+
+tlsp->resumption = RESUME_SUPPORTED;
+/* Pick up a previous session, saved on an old ticket */
+tls_retrieve_session(tlsp, ssl, host->address);
+return TRUE;
+}
+
+static void
+tls_client_resume_posthandshake(exim_openssl_client_tls_ctx * exim_client_ctx,
+ tls_support * tlsp)
+{
+if (SSL_session_reused(exim_client_ctx->ssl))
+ {
+ DEBUG(D_tls) debug_printf("The session was reused\n");
+ tlsp->resumption |= RESUME_USED;
+ }
+}
+#endif /* !DISABLE_TLS_RESUME */
+
+
+#ifdef EXIM_HAVE_ALPN
+/* Expand and convert an Exim list to an ALPN list. False return for fail.
+NULL plist return for silent no-ALPN.
+*/
+
+static BOOL
+tls_alpn_plist(const uschar * tls_alpn, const uschar ** plist, unsigned * plen,
+ uschar ** errstr)
+{
+uschar * exp_alpn;
+
+if (!expand_check(tls_alpn, US"tls_alpn", &exp_alpn, errstr))
+ return FALSE;
+
+if (!exp_alpn)
+ {
+ DEBUG(D_tls) debug_printf("Setting TLS ALPN forced to fail, not sending\n");
+ *plist = NULL;
+ }
+else
+ {
+ /* The server implementation only accepts exactly one protocol name
+ but it's little extra code complexity in the client. */
+
+ const uschar * list = exp_alpn;
+ uschar * p = store_get(Ustrlen(exp_alpn), is_tainted(exp_alpn)), * s, * t;
+ int sep = 0;
+ uschar len;
+
+ for (t = p; s = string_nextinlist(&list, &sep, NULL, 0); t += len)
+ {
+ *t++ = len = (uschar) Ustrlen(s);
+ memcpy(t, s, len);
+ }
+ *plist = (*plen = t - p) ? p : NULL;
+ }
+return TRUE;
+}
+#endif /* EXIM_HAVE_ALPN */
+
+
/*************************************************
* Start a TLS session in a client *
*************************************************/
/* Called from the smtp transport after STARTTLS has been accepted.
-Argument:
- fd the fd of the connection
- host connected host (for messages and option-tests)
- addr the first address (for some randomness; can be NULL)
- tb transport (always smtp)
- tlsa_dnsa tlsa lookup, if DANE, else null
- tlsp record details of channel configuration here; must be non-NULL
- errstr error string pointer
-
-Returns: Pointer to TLS session context, or NULL on error
+Arguments:
+ cctx connection context
+ conn_args connection details
+ cookie datum for randomness; can be NULL
+ tlsp record details of TLS channel configuration here; must be non-NULL
+ errstr error string pointer
+
+Returns: TRUE for success with TLS session context set in connection context,
+ FALSE on error
*/
-void *
-tls_client_start(int fd, host_item *host, address_item *addr,
- transport_instance * tb,
-#ifdef SUPPORT_DANE
- dns_answer * tlsa_dnsa,
-#endif
- tls_support * tlsp, uschar ** errstr)
+BOOL
+tls_client_start(client_conn_ctx * cctx, smtp_connect_args * conn_args,
+ void * cookie, tls_support * tlsp, uschar ** errstr)
{
+host_item * host = conn_args->host; /* for msgs and option-tests */
+transport_instance * tb = conn_args->tblock; /* always smtp or NULL */
smtp_transport_options_block * ob = tb
? (smtp_transport_options_block *)tb->options_block
: &smtp_transport_option_defaults;
exim_openssl_client_tls_ctx * exim_client_ctx;
-static uschar peerdn[256];
uschar * expciphers;
int rc;
-static uschar cipherbuf[256];
+static uschar peerdn[256];
#ifndef DISABLE_OCSP
BOOL request_ocsp = FALSE;
rc = store_pool;
store_pool = POOL_PERM;
-exim_client_ctx = store_get(sizeof(exim_openssl_client_tls_ctx));
+exim_client_ctx = store_get(sizeof(exim_openssl_client_tls_ctx), FALSE);
+exim_client_ctx->corked = NULL;
store_pool = rc;
#ifdef SUPPORT_DANE
#ifndef DISABLE_OCSP
{
# ifdef SUPPORT_DANE
- if ( tlsa_dnsa
+ /*XXX this should be moved to caller, to be common across gnutls/openssl */
+ if ( conn_args->dane
&& ob->hosts_request_ocsp[0] == '*'
&& ob->hosts_request_ocsp[1] == '\0'
)
}
#endif
-rc = tls_init(&exim_client_ctx->ctx, host, NULL,
- ob->tls_certificate, ob->tls_privatekey,
+rc = tls_init(host, ob,
#ifndef DISABLE_OCSP
(void *)(long)request_ocsp,
#endif
- addr, &client_static_cbinfo, errstr);
-if (rc != OK) return NULL;
+ cookie, &client_static_state, tlsp, errstr);
+if (rc != OK) return FALSE;
+
+exim_client_ctx->ctx = client_static_state->lib_state.lib_ctx;
tlsp->certificate_verified = FALSE;
client_verify_callback_called = FALSE;
expciphers = NULL;
#ifdef SUPPORT_DANE
-if (tlsa_dnsa)
+if (conn_args->dane)
{
/* We fall back to tls_require_ciphers if unset, empty or forced failure, but
other failures should be treated as problems. */
if (ob->dane_require_tls_ciphers &&
!expand_check(ob->dane_require_tls_ciphers, US"dane_require_tls_ciphers",
&expciphers, errstr))
- return NULL;
+ return FALSE;
if (expciphers && *expciphers == '\0')
expciphers = NULL;
}
if (!expciphers &&
!expand_check(ob->tls_require_ciphers, US"tls_require_ciphers",
&expciphers, errstr))
- return NULL;
+ return FALSE;
/* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they
are separated by underscores. So that I can use either form in my tests, and
if (!SSL_CTX_set_cipher_list(exim_client_ctx->ctx, CS expciphers))
{
tls_error(US"SSL_CTX_set_cipher_list", host, NULL, errstr);
- return NULL;
+ return FALSE;
}
}
#ifdef SUPPORT_DANE
-if (tlsa_dnsa)
+if (conn_args->dane)
{
SSL_CTX_set_verify(exim_client_ctx->ctx,
SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
if (!DANESSL_library_init())
{
tls_error(US"library init", host, NULL, errstr);
- return NULL;
+ return FALSE;
}
if (DANESSL_CTX_init(exim_client_ctx->ctx) <= 0)
{
tls_error(US"context init", host, NULL, errstr);
- return NULL;
+ return FALSE;
}
}
else
#endif
- if (tls_client_basic_ctx_init(exim_client_ctx->ctx, host, ob,
- client_static_cbinfo, errstr) != OK)
- return NULL;
+if (tls_client_basic_ctx_init(exim_client_ctx->ctx, host, ob,
+ client_static_state, errstr) != OK)
+ return FALSE;
+
+#ifndef DISABLE_TLS_RESUME
+tls_client_ctx_resume_prehandshake(exim_client_ctx, tlsp, ob, host);
+#endif
+
if (!(exim_client_ctx->ssl = SSL_new(exim_client_ctx->ctx)))
{
tls_error(US"SSL_new", host, NULL, errstr);
- return NULL;
+ return FALSE;
}
SSL_set_session_id_context(exim_client_ctx->ssl, sid_ctx, Ustrlen(sid_ctx));
-SSL_set_fd(exim_client_ctx->ssl, fd);
+
+SSL_set_fd(exim_client_ctx->ssl, cctx->sock);
SSL_set_connect_state(exim_client_ctx->ssl);
if (ob->tls_sni)
{
if (!expand_check(ob->tls_sni, US"tls_sni", &tlsp->sni, errstr))
- return NULL;
+ return FALSE;
if (!tlsp->sni)
{
DEBUG(D_tls) debug_printf("Setting TLS SNI forced to fail, not sending\n");
}
}
+if (ob->tls_alpn)
+#ifdef EXIM_HAVE_ALPN
+ {
+ const uschar * plist;
+ unsigned plen;
+
+ if (!tls_alpn_plist(ob->tls_alpn, &plist, &plen, errstr))
+ return FALSE;
+ if (plist)
+ if (SSL_set_alpn_protos(exim_client_ctx->ssl, plist, plen) != 0)
+ {
+ tls_error(US"alpn init", host, NULL, errstr);
+ return FALSE;
+ }
+ else
+ DEBUG(D_tls) debug_printf("Setting TLS ALPN '%s'\n", ob->tls_alpn);
+ }
+#else
+ log_write(0, LOG_MAIN, "ALPN unusable with this OpenSSL library version; ignoring \"%s\"\n",
+ ob->tls_alpn);
+#endif
+
#ifdef SUPPORT_DANE
-if (tlsa_dnsa)
- if (dane_tlsa_load(exim_client_ctx->ssl, host, tlsa_dnsa, errstr) != OK)
- return NULL;
+if (conn_args->dane)
+ if (dane_tlsa_load(exim_client_ctx->ssl, host, &conn_args->tlsa_dnsa, errstr) != OK)
+ return FALSE;
#endif
#ifndef DISABLE_OCSP
if (request_ocsp)
{
SSL_set_tlsext_status_type(exim_client_ctx->ssl, TLSEXT_STATUSTYPE_ocsp);
- client_static_cbinfo->u_ocsp.client.verify_required = require_ocsp;
+ client_static_state->u_ocsp.client.verify_required = require_ocsp;
tlsp->ocsp = OCSP_NOT_RESP;
}
#endif
+#ifndef DISABLE_TLS_RESUME
+if (!tls_client_ssl_resume_prehandshake(exim_client_ctx->ssl, tlsp, host,
+ errstr))
+ return FALSE;
+#endif
+
#ifndef DISABLE_EVENT
-client_static_cbinfo->event_action = tb ? tb->event_action : NULL;
+client_static_state->event_action = tb ? tb->event_action : NULL;
#endif
/* There doesn't seem to be a built-in timeout on connection. */
ALARM_CLR(0);
#ifdef SUPPORT_DANE
-if (tlsa_dnsa)
+if (conn_args->dane)
DANESSL_cleanup(exim_client_ctx->ssl);
#endif
if (rc <= 0)
{
tls_error(US"SSL_connect", host, sigalrm_seen ? US"timed out" : NULL, errstr);
- return NULL;
+ return FALSE;
}
-DEBUG(D_tls) debug_printf("SSL_connect succeeded\n");
+DEBUG(D_tls)
+ {
+ debug_printf("SSL_connect succeeded\n");
+#ifdef EXIM_HAVE_OPENSSL_KEYLOG
+ {
+ BIO * bp = BIO_new_fp(debug_file, BIO_NOCLOSE);
+ SSL_SESSION_print_keylog(bp, SSL_get_session(exim_client_ctx->ssl));
+ BIO_free(bp);
+ }
+#endif
+ }
+
+#ifndef DISABLE_TLS_RESUME
+tls_client_resume_posthandshake(exim_client_ctx, tlsp);
+#endif
+
+#ifdef EXIM_HAVE_ALPN
+if (ob->tls_alpn) /* We requested. See what was negotiated. */
+ {
+ const uschar * name;
+ unsigned len;
+
+ SSL_get0_alpn_selected(exim_client_ctx->ssl, &name, &len);
+ if (len > 0)
+ { DEBUG(D_tls) debug_printf("ALPN negotiated %u: '%.*s'\n", len, (int)*name, name+1); }
+ else if (verify_check_given_host(CUSS &ob->hosts_require_alpn, host) == OK)
+ {
+ /* Would like to send a relevant fatal Alert, but OpenSSL has no API */
+ tls_error(US"handshake", host, US"ALPN required but not negotiated", errstr);
+ return FALSE;
+ }
+ }
+#endif
+#ifdef SSL_get_extms_support
+tlsp->ext_master_secret = SSL_get_extms_support(exim_client_ctx->ssl) == 1;
+#endif
peer_cert(exim_client_ctx->ssl, tlsp, peerdn, sizeof(peerdn));
-construct_cipher_name(exim_client_ctx->ssl, cipherbuf, sizeof(cipherbuf), &tlsp->bits);
-tlsp->cipher = cipherbuf;
+tlsp->ver = tlsver_name(exim_client_ctx->ssl);
+tlsp->cipher = construct_cipher_name(exim_client_ctx->ssl, tlsp->ver, &tlsp->bits);
+tlsp->cipher_stdname = cipher_stdname_ssl(exim_client_ctx->ssl);
/* Record the certificate we presented */
{
tlsp->ourcert = crt ? X509_dup(crt) : NULL;
}
-tlsp->active.sock = fd;
+/*XXX will this work with continued-TLS? */
+/* Channel-binding info for authenticators */
+ {
+ uschar c, * s;
+ size_t len = SSL_get_finished(exim_client_ctx->ssl, &c, 0);
+ int old_pool = store_pool;
+
+ SSL_get_finished(exim_client_ctx->ssl, s = store_get((int)len, TRUE), len);
+ store_pool = POOL_PERM;
+ tlsp->channelbinding = b64encode_taint(CUS s, (int)len, TRUE);
+ store_pool = old_pool;
+ DEBUG(D_tls) debug_printf("Have channel bindings cached for possible auth usage %p %p\n", tlsp->channelbinding, tlsp);
+ }
+
+tlsp->active.sock = cctx->sock;
tlsp->active.tls_ctx = exim_client_ctx;
-return exim_client_ctx;
+cctx->tls_ctx = exim_client_ctx;
+return TRUE;
}
static BOOL
tls_refill(unsigned lim)
{
+SSL * ssl = state_server.lib_state.lib_ssl;
int error;
int inbytes;
-DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", server_ssl,
+DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", ssl,
ssl_xfer_buffer, ssl_xfer_buffer_size);
+ERR_clear_error();
if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
-inbytes = SSL_read(server_ssl, CS ssl_xfer_buffer,
+inbytes = SSL_read(ssl, CS ssl_xfer_buffer,
MIN(ssl_xfer_buffer_size, lim));
-error = SSL_get_error(server_ssl, inbytes);
+error = SSL_get_error(ssl, inbytes);
if (smtp_receive_timeout > 0) ALARM_CLR(0);
if (had_command_timeout) /* set by signal handler */
case SSL_ERROR_ZERO_RETURN:
DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n");
- receive_getc = smtp_getc;
- receive_getbuf = smtp_getbuf;
- receive_get_cache = smtp_get_cache;
- receive_ungetc = smtp_ungetc;
- receive_feof = smtp_feof;
- receive_ferror = smtp_ferror;
- receive_smtp_buffered = smtp_buffered;
-
- if (SSL_get_shutdown(server_ssl) == SSL_RECEIVED_SHUTDOWN)
- SSL_shutdown(server_ssl);
-
-#ifndef DISABLE_OCSP
- sk_X509_pop_free(server_static_cbinfo->verify_stack, X509_free);
- server_static_cbinfo->verify_stack = NULL;
-#endif
- SSL_free(server_ssl);
- SSL_CTX_free(server_ctx);
- server_ctx = NULL;
- server_ssl = NULL;
- tls_in.active.sock = -1;
- tls_in.active.tls_ctx = NULL;
- tls_in.bits = 0;
- tls_in.cipher = NULL;
- tls_in.peerdn = NULL;
- tls_in.sni = NULL;
+ if (SSL_get_shutdown(ssl) == SSL_RECEIVED_SHUTDOWN)
+ SSL_shutdown(ssl);
+ tls_close(NULL, TLS_NO_SHUTDOWN);
return FALSE;
/* Handle genuine errors */
return ssl_xfer_buffer[ssl_xfer_buffer_lwm++];
}
+BOOL
+tls_hasc(void)
+{
+return ssl_xfer_buffer_lwm < ssl_xfer_buffer_hwm;
+}
+
uschar *
tls_getbuf(unsigned * len)
{
void
-tls_get_cache()
+tls_get_cache(unsigned lim)
{
#ifndef DISABLE_DKIM
int n = ssl_xfer_buffer_hwm - ssl_xfer_buffer_lwm;
+debug_printf("tls_get_cache\n");
+if (n > lim)
+ n = lim;
if (n > 0)
dkim_exim_verify_feed(ssl_xfer_buffer+ssl_xfer_buffer_lwm, n);
#endif
BOOL
tls_could_read(void)
{
-return ssl_xfer_buffer_lwm < ssl_xfer_buffer_hwm || SSL_pending(server_ssl) > 0;
+return ssl_xfer_buffer_lwm < ssl_xfer_buffer_hwm
+ || SSL_pending(state_server.lib_state.lib_ssl) > 0;
}
int
tls_read(void * ct_ctx, uschar *buff, size_t len)
{
-SSL * ssl = ct_ctx ? ((exim_openssl_client_tls_ctx *)ct_ctx)->ssl : server_ssl;
+SSL * ssl = ct_ctx ? ((exim_openssl_client_tls_ctx *)ct_ctx)->ssl
+ : state_server.lib_state.lib_ssl;
int inbytes;
int error;
DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", ssl,
buff, (unsigned int)len);
+ERR_clear_error();
inbytes = SSL_read(ssl, CS buff, len);
error = SSL_get_error(ssl, inbytes);
Returns: the number of bytes after a successful write,
-1 after a failed write
-Used by both server-side and client-side TLS.
+Used by both server-side and client-side TLS. Calling with len zero and more unset
+will flush buffered writes; buff can be null for this case.
*/
int
-tls_write(void * ct_ctx, const uschar *buff, size_t len, BOOL more)
+tls_write(void * ct_ctx, const uschar * buff, size_t len, BOOL more)
{
-int outbytes, error, left;
-SSL * ssl = ct_ctx ? ((exim_openssl_client_tls_ctx *)ct_ctx)->ssl : server_ssl;
-static gstring * corked = NULL;
+size_t olen = len;
+int outbytes, error;
+SSL * ssl = ct_ctx
+ ? ((exim_openssl_client_tls_ctx *)ct_ctx)->ssl
+ : state_server.lib_state.lib_ssl;
+static gstring * server_corked = NULL;
+gstring ** corkedp = ct_ctx
+ ? &((exim_openssl_client_tls_ctx *)ct_ctx)->corked : &server_corked;
+gstring * corked = *corkedp;
DEBUG(D_tls) debug_printf("%s(%p, %lu%s)\n", __FUNCTION__,
buff, (unsigned long)len, more ? ", more" : "");
/* Lacking a CORK or MSG_MORE facility (such as GnuTLS has) we copy data when
"more" is notified. This hack is only ok if small amounts are involved AND only
one stream does it, in one context (i.e. no store reset). Currently it is used
-for the responses to the received SMTP MAIL , RCPT, DATA sequence, only. */
-/*XXX + if PIPE_COMMAND, banner & ehlo-resp for smmtp-on-connect. Suspect there's
-a store reset there. */
-
-if (!ct_ctx && (more || corked))
+for the responses to the received SMTP MAIL , RCPT, DATA sequence, only.
+We support callouts done by the server process by using a separate client
+context for the stashed information. */
+/* + if PIPE_COMMAND, banner & ehlo-resp for smmtp-on-connect. Suspect there's
+a store reset there, so use POOL_PERM. */
+/* + if CHUNKING, cmds EHLO,MAIL,RCPT(s),BDAT */
+
+if (more || corked)
{
-#ifdef EXPERIMENTAL_PIPE_CONNECT
+ if (!len) buff = US &error; /* dummy just so that string_catn is ok */
+
int save_pool = store_pool;
store_pool = POOL_PERM;
-#endif
corked = string_catn(corked, buff, len);
-#ifdef EXPERIMENTAL_PIPE_CONNECT
store_pool = save_pool;
-#endif
if (more)
+ {
+ *corkedp = corked;
return len;
+ }
buff = CUS corked->s;
len = corked->ptr;
- corked = NULL;
+ *corkedp = NULL;
}
-for (left = len; left > 0;)
+for (int left = len; left > 0;)
{
DEBUG(D_tls) debug_printf("SSL_write(%p, %p, %d)\n", ssl, buff, left);
+ ERR_clear_error();
outbytes = SSL_write(ssl, CS buff, left);
error = SSL_get_error(ssl, outbytes);
DEBUG(D_tls) debug_printf("outbytes=%d error=%d\n", outbytes, error);
switch (error)
{
+ case SSL_ERROR_NONE: /* the usual case */
+ left -= outbytes;
+ buff += outbytes;
+ break;
+
case SSL_ERROR_SSL:
ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
log_write(0, LOG_MAIN, "TLS error (SSL_write): %s", ssl_errstring);
return -1;
- case SSL_ERROR_NONE:
- left -= outbytes;
- buff += outbytes;
- break;
-
case SSL_ERROR_ZERO_RETURN:
log_write(0, LOG_MAIN, "SSL channel closed on write");
return -1;
case SSL_ERROR_SYSCALL:
- log_write(0, LOG_MAIN, "SSL_write: (from %s) syscall: %s",
- sender_fullhost ? sender_fullhost : US"<unknown>",
- strerror(errno));
+ if (ct_ctx || errno != ECONNRESET || !f.smtp_in_quit)
+ log_write(0, LOG_MAIN, "SSL_write: (from %s) syscall: %s",
+ sender_fullhost ? sender_fullhost : US"<unknown>",
+ strerror(errno));
+ else if (LOGGING(protocol_detail))
+ log_write(0, LOG_MAIN, "[%s] after QUIT, client reset TCP before"
+ " SMTP response and TLS close\n", sender_host_address);
+ else
+ DEBUG(D_tls) debug_printf("[%s] SSL_write: after QUIT,"
+ " client reset TCP before TLS close\n", sender_host_address);
return -1;
default:
return -1;
}
}
-return len;
+return olen;
}
+/*
+Arguments:
+ ct_ctx client TLS context pointer, or NULL for the one global server context
+*/
+
+void
+tls_shutdown_wr(void * ct_ctx)
+{
+exim_openssl_client_tls_ctx * o_ctx = ct_ctx;
+SSL ** sslp = o_ctx ? &o_ctx->ssl : (SSL **) &state_server.lib_state.lib_ssl;
+int * fdp = o_ctx ? &tls_out.active.sock : &tls_in.active.sock;
+int rc;
+
+if (*fdp < 0) return; /* TLS was not active */
+
+tls_write(ct_ctx, NULL, 0, FALSE); /* flush write buffer */
+
+HDEBUG(D_transport|D_tls|D_acl|D_v) debug_printf_indent(" SMTP(TLS shutdown)>>\n");
+rc = SSL_shutdown(*sslp);
+if (rc < 0) DEBUG(D_tls)
+ {
+ ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
+ debug_printf("SSL_shutdown: %s\n", ssl_errstring);
+ }
+}
+
/*************************************************
* Close down a TLS session *
*************************************************/
Arguments:
ct_ctx client TLS context pointer, or NULL for the one global server context
- shutdown 1 if TLS close-alert is to be sent,
+ do_shutdown 0 no data-flush or TLS close-alert
+ 1 if TLS close-alert is to be sent,
2 if also response to be waited for
Returns: nothing
*/
void
-tls_close(void * ct_ctx, int shutdown)
+tls_close(void * ct_ctx, int do_shutdown)
{
exim_openssl_client_tls_ctx * o_ctx = ct_ctx;
-SSL_CTX **ctxp = o_ctx ? &o_ctx->ctx : &server_ctx;
-SSL **sslp = o_ctx ? &o_ctx->ssl : &server_ssl;
-int *fdp = o_ctx ? &tls_out.active.sock : &tls_in.active.sock;
+SSL ** sslp = o_ctx ? &o_ctx->ssl : (SSL **) &state_server.lib_state.lib_ssl;
+int * fdp = o_ctx ? &tls_out.active.sock : &tls_in.active.sock;
if (*fdp < 0) return; /* TLS was not active */
-if (shutdown)
+if (do_shutdown)
{
int rc;
DEBUG(D_tls) debug_printf("tls_close(): shutting down TLS%s\n",
- shutdown > 1 ? " (with response-wait)" : "");
+ do_shutdown > 1 ? " (with response-wait)" : "");
+
+ tls_write(ct_ctx, NULL, 0, FALSE); /* flush write buffer */
if ( (rc = SSL_shutdown(*sslp)) == 0 /* send "close notify" alert */
- && shutdown > 1)
+ && do_shutdown > 1)
{
ALARM(2);
rc = SSL_shutdown(*sslp); /* wait for response */
}
}
-#ifndef DISABLE_OCSP
if (!o_ctx) /* server side */
{
- sk_X509_pop_free(server_static_cbinfo->verify_stack, X509_free);
- server_static_cbinfo->verify_stack = NULL;
- }
+#ifndef DISABLE_OCSP
+ sk_X509_pop_free(state_server.verify_stack, X509_free);
+ state_server.verify_stack = NULL;
#endif
-SSL_CTX_free(*ctxp);
+ receive_getc = smtp_getc;
+ receive_getbuf = smtp_getbuf;
+ receive_get_cache = smtp_get_cache;
+ receive_hasc = smtp_hasc;
+ receive_ungetc = smtp_ungetc;
+ receive_feof = smtp_feof;
+ receive_ferror = smtp_ferror;
+ receive_smtp_buffered = smtp_buffered;
+ tls_in.active.tls_ctx = NULL;
+ tls_in.sni = NULL;
+ /* Leave bits, peercert, cipher, peerdn, certificate_verified set, for logging */
+ }
+
SSL_free(*sslp);
-*ctxp = NULL;
*sslp = NULL;
*fdp = -1;
}
SSL_CTX *ctx;
uschar *s, *expciphers, *err;
-/* this duplicates from tls_init(), we need a better "init just global
-state, for no specific purpose" singleton function of our own */
-
-#ifdef EXIM_NEED_OPENSSL_INIT
-SSL_load_error_strings();
-OpenSSL_add_ssl_algorithms();
-#endif
-#if (OPENSSL_VERSION_NUMBER >= 0x0090800fL) && !defined(OPENSSL_NO_SHA256)
-/* SHA256 is becoming ever more popular. This makes sure it gets added to the
-list of available digests. */
-EVP_add_digest(EVP_sha256());
-#endif
+tls_openssl_init();
if (!(tls_require_ciphers && *tls_require_ciphers))
return NULL;
err = NULL;
-#ifdef EXIM_HAVE_OPENSSL_TLS_METHOD
-if (!(ctx = SSL_CTX_new(TLS_server_method())))
-#else
-if (!(ctx = SSL_CTX_new(SSLv23_server_method())))
-#endif
+if (lib_ctx_new(&ctx, NULL, &err) == OK)
{
- ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
- return string_sprintf("SSL_CTX_new() failed: %s", ssl_errstring);
- }
+ DEBUG(D_tls)
+ debug_printf("tls_require_ciphers expands to \"%s\"\n", expciphers);
-DEBUG(D_tls)
- debug_printf("tls_require_ciphers expands to \"%s\"\n", expciphers);
+ if (!SSL_CTX_set_cipher_list(ctx, CS expciphers))
+ {
+ ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
+ err = string_sprintf("SSL_CTX_set_cipher_list(%s) failed: %s",
+ expciphers, ssl_errstring);
+ }
-if (!SSL_CTX_set_cipher_list(ctx, CS expciphers))
- {
- ERR_error_string_n(ERR_get_error(), ssl_errstring, sizeof(ssl_errstring));
- err = string_sprintf("SSL_CTX_set_cipher_list(%s) failed: %s",
- expciphers, ssl_errstring);
+ SSL_CTX_free(ctx);
}
-
-SSL_CTX_free(ctx);
-
return err;
}
int i, needed_len;
static pid_t pidlast = 0;
pid_t pidnow;
-uschar *p;
uschar smallbuf[sizeof(r)];
if (max <= 1)
}
r = 0;
-for (p = smallbuf; needed_len; --needed_len, ++p)
- {
- r *= 256;
- r += *p;
- }
+for (uschar * p = smallbuf; needed_len; --needed_len, ++p)
+ r = 256 * r + *p;
/* We don't particularly care about weighted results; if someone wants
smooth distribution and cares enough then they should submit a patch then. */
tls_openssl_options_parse(uschar *option_spec, long *results)
{
long result, item;
-uschar *s, *end;
-uschar keep_c;
+uschar * exp, * end;
BOOL adding, item_parsed;
+/* Server: send no (<= TLS1.2) session tickets */
result = SSL_OP_NO_TICKET;
+
/* Prior to 4.80 we or'd in SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS; removed
- * from default because it increases BEAST susceptibility. */
+from default because it increases BEAST susceptibility. */
#ifdef SSL_OP_NO_SSLv2
result |= SSL_OP_NO_SSLv2;
#endif
+#ifdef SSL_OP_NO_SSLv3
+result |= SSL_OP_NO_SSLv3;
+#endif
#ifdef SSL_OP_SINGLE_DH_USE
result |= SSL_OP_SINGLE_DH_USE;
#endif
+#ifdef SSL_OP_NO_RENEGOTIATION
+result |= SSL_OP_NO_RENEGOTIATION;
+#endif
if (!option_spec)
{
return TRUE;
}
-for (s=option_spec; *s != '\0'; /**/)
+if (!expand_check(option_spec, US"openssl_options", &exp, &end))
+ return FALSE;
+
+for (uschar * s = exp; *s; /**/)
{
while (isspace(*s)) ++s;
if (*s == '\0')
return FALSE;
}
adding = *s++ == '+';
- for (end = s; (*end != '\0') && !isspace(*end); ++end) /**/ ;
- keep_c = *end;
- *end = '\0';
- item_parsed = tls_openssl_one_option_parse(s, &item);
- *end = keep_c;
+ for (end = s; *end && !isspace(*end); ) end++;
+ item_parsed = tls_openssl_one_option_parse(string_copyn(s, end-s), &item);
if (!item_parsed)
{
DEBUG(D_tls) debug_printf("openssl option setting unrecognised: \"%s\"\n", s);
return FALSE;
}
- DEBUG(D_tls) debug_printf("openssl option, %s from %lx: %lx (%s)\n",
- adding ? "adding" : "removing", result, item, s);
+ DEBUG(D_tls) debug_printf("openssl option, %s %08lx: %08lx (%s)\n",
+ adding ? "adding to " : "removing from", result, item, s);
if (adding)
result |= item;
else
git://git.exim.org / exim.git / blobdiff