* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2015 */
+/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */
/* Copyright (c) Phil Pennock 2012 */
The code herein is a revamp of GnuTLS integration using the current APIs; the
original tls-gnu.c was based on a patch which was contributed by Nikos
-Mavroyanopoulos. The revamp is partially a rewrite, partially cut&paste as
+Mavrogiannopoulos. The revamp is partially a rewrite, partially cut&paste as
appropriate.
APIs current as of GnuTLS 2.12.18; note that the GnuTLS manual is for GnuTLS 3,
#include <gnutls/x509.h>
/* man-page is incorrect, gnutls_rnd() is not in gnutls.h: */
#include <gnutls/crypto.h>
+
/* needed to disable PKCS11 autoload unless requested */
#if GNUTLS_VERSION_NUMBER >= 0x020c00
# include <gnutls/pkcs11.h>
#if GNUTLS_VERSION_NUMBER >= 0x030014
# define SUPPORT_SYSDEFAULT_CABUNDLE
#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030104
+# define GNUTLS_CERT_VFY_STATUS_PRINT
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030109
+# define SUPPORT_CORK
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x03010a
+# define SUPPORT_GNUTLS_SESS_DESC
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030500
+# define SUPPORT_GNUTLS_KEYLOG
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030506 && !defined(DISABLE_OCSP)
+# define SUPPORT_SRV_OCSP_STACK
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030603
+# define EXIM_HAVE_TLS1_3
+# define SUPPORT_GNUTLS_EXT_RAW_PARSE
+# define GNUTLS_OCSP_STATUS_REQUEST_GET2
+#endif
+
+#ifdef SUPPORT_DANE
+# if GNUTLS_VERSION_NUMBER >= 0x030000
+# define DANESSL_USAGE_DANE_TA 2
+# define DANESSL_USAGE_DANE_EE 3
+# else
+# error GnuTLS version too early for DANE
+# endif
+# if GNUTLS_VERSION_NUMBER < 0x999999
+# define GNUTLS_BROKEN_DANE_VALIDATION
+# endif
+#endif
+
+#ifdef EXPERIMENTAL_TLS_RESUME
+# if GNUTLS_VERSION_NUMBER < 0x030603
+# error GNUTLS version too early for session-resumption
+# endif
+#endif
#ifndef DISABLE_OCSP
# include <gnutls/ocsp.h>
#endif
+#ifdef SUPPORT_DANE
+# include <gnutls/dane.h>
+#endif
+
+#include "tls-cipher-stdname.c"
+
+
+#ifdef MACRO_PREDEF
+void
+options_tls(void)
+{
+# ifdef EXPERIMENTAL_TLS_RESUME
+builtin_macro_create_var(US"_RESUME_DECODE", RESUME_DECODE_STRING );
+# endif
+# ifdef EXIM_HAVE_TLS1_3
+builtin_macro_create(US"_HAVE_TLS1_3");
+# endif
+}
+#else
+
/* GnuTLS 2 vs 3
/* Values for verify_requirement */
enum peer_verify_requirement
- { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED };
+ { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED, VERIFY_DANE };
/* This holds most state for server or client; with this, we can set up an
outbound TLS-enabled connection in an ACL callout, while not stomping all
int fd_in;
int fd_out;
BOOL peer_cert_verified;
+ BOOL peer_dane_verified;
BOOL trigger_sni_changes;
BOOL have_set_peerdn;
- const struct host_item *host;
- gnutls_x509_crt_t peercert;
+ const struct host_item *host; /* NULL if server */
+ gnutls_x509_crt_t peercert;
uschar *peerdn;
uschar *ciphersuite;
uschar *received_sni;
uschar *exp_tls_verify_certificates;
uschar *exp_tls_crl;
uschar *exp_tls_require_ciphers;
- uschar *exp_tls_ocsp_file;
const uschar *exp_tls_verify_cert_hostnames;
#ifndef DISABLE_EVENT
uschar *event_action;
#endif
+#ifdef SUPPORT_DANE
+ char * const * dane_data;
+ const int * dane_data_len;
+#endif
tls_support *tlsp; /* set in tls_init() */
uschar *xfer_buffer;
int xfer_buffer_lwm;
int xfer_buffer_hwm;
- int xfer_eof;
- int xfer_error;
+ BOOL xfer_eof; /*XXX never gets set! */
+ BOOL xfer_error;
} exim_gnutls_state_st;
static const exim_gnutls_state_st exim_gnutls_state_init = {
- NULL, NULL, NULL, VERIFY_NONE, -1, -1, FALSE, FALSE, FALSE,
- NULL, NULL, NULL, NULL,
- NULL, NULL, NULL, NULL, NULL, NULL,
- NULL, NULL, NULL, NULL, NULL, NULL, NULL,
- NULL,
-#ifndef DISABLE_EVENT
- NULL,
-#endif
- NULL,
- NULL, 0, 0, 0, 0,
+ /* all elements not explicitly intialised here get 0/NULL/FALSE */
+ .fd_in = -1,
+ .fd_out = -1,
};
/* Not only do we have our own APIs which don't pass around state, assuming
XXX But see gnutls_session_get_ptr()
*/
-static exim_gnutls_state_st state_server, state_client;
+static exim_gnutls_state_st state_server;
/* dh_params are initialised once within the lifetime of a process using TLS;
if we used TLS in a long-lived daemon, we'd have to reconsider this. But we
static gnutls_dh_params_t dh_server_params = NULL;
-/* No idea how this value was chosen; preserving it. Default is 3600. */
-
-static const int ssl_session_timeout = 200;
+static int ssl_session_timeout = 7200; /* Two hours */
-static const char * const exim_default_gnutls_priority = "NORMAL";
+static const uschar * const exim_default_gnutls_priority = US"NORMAL";
/* Guard library core initialisation */
#ifndef DISABLE_OCSP
static BOOL gnutls_buggy_ocsp = FALSE;
+static BOOL exim_testharness_disable_ocsp_validity_check = FALSE;
#endif
+#ifdef EXPERIMENTAL_TLS_RESUME
+static gnutls_datum_t server_sessticket_key;
+#endif
/* ------------------------------------------------------------------------ */
/* macros */
/* Set this to control gnutls_global_set_log_level(); values 0 to 9 will setup
the library logging; a value less than 0 disables the calls to set up logging
-callbacks. */
+callbacks. GNuTLS also looks for an environment variable - except not for
+setuid binaries, making it useless - "GNUTLS_DEBUG_LEVEL".
+Allegedly the testscript line "GNUTLS_DEBUG_LEVEL=9 sudo exim ..." would work,
+but the env var must be added to /etc/sudoers too. */
#ifndef EXIM_GNUTLS_LIBRARY_LOG_LEVEL
# define EXIM_GNUTLS_LIBRARY_LOG_LEVEL -1
#endif
# define EXIM_SERVER_DH_BITS_PRE2_12 1024
#endif
-#define exim_gnutls_err_check(Label) do { \
- if (rc != GNUTLS_E_SUCCESS) { return tls_error((Label), gnutls_strerror(rc), host); } } while (0)
-
-#define expand_check_tlsvar(Varname) expand_check(state->Varname, US #Varname, &state->exp_##Varname)
+#define expand_check_tlsvar(Varname, errstr) \
+ expand_check(state->Varname, US #Varname, &state->exp_##Varname, errstr)
#if GNUTLS_VERSION_NUMBER >= 0x020c00
# define HAVE_GNUTLS_SESSION_CHANNEL_BINDING
static int exim_sni_handling_cb(gnutls_session_t session);
-#ifndef DISABLE_OCSP
-static int server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,
- gnutls_datum_t * ocsp_response);
+#ifdef EXPERIMENTAL_TLS_RESUME
+static int
+tls_server_ticket_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg);
#endif
+/* Daemon one-time initialisation */
+void
+tls_daemon_init(void)
+{
+#ifdef EXPERIMENTAL_TLS_RESUME
+/* We are dependent on the GnuTLS implementation of the Session Ticket
+encryption; both the strength and the key rotation period. We hope that
+the strength at least matches that of the ciphersuite (but GnuTLS does not
+document this). */
+
+static BOOL once = FALSE;
+if (once) return;
+once = TRUE;
+gnutls_session_ticket_key_generate(&server_sessticket_key); /* >= 2.10.0 */
+if (f.running_in_test_harness) ssl_session_timeout = 6;
+#endif
+}
/* ------------------------------------------------------------------------ */
/* Static functions */
usually obtained from gnutls_strerror()
host NULL if setting up a server;
the connected host if setting up a client
+ errstr pointer to returned error string
Returns: OK/DEFER/FAIL
*/
static int
-tls_error(const uschar *prefix, const char *msg, const host_item *host)
+tls_error(const uschar *prefix, const uschar *msg, const host_item *host,
+ uschar ** errstr)
{
-if (host)
- {
- log_write(0, LOG_MAIN, "H=%s [%s] TLS error on connection (%s)%s%s",
- host->name, host->address, prefix, msg ? ": " : "", msg ? msg : "");
- return FAIL;
- }
-else
- {
- uschar *conn_info = smtp_get_connection_info();
- if (Ustrncmp(conn_info, US"SMTP ", 5) == 0)
- conn_info += 5;
- /* I'd like to get separated H= here, but too hard for now */
- log_write(0, LOG_MAIN, "TLS error on %s (%s)%s%s",
- conn_info, prefix, msg ? ": " : "", msg ? msg : "");
- return DEFER;
- }
+if (errstr)
+ *errstr = string_sprintf("(%s)%s%s", prefix, msg ? ": " : "", msg ? msg : US"");
+return host ? FAIL : DEFER;
}
+static int
+tls_error_gnu(const uschar *prefix, int err, const host_item *host,
+ uschar ** errstr)
+{
+return tls_error(prefix, US gnutls_strerror(err), host, errstr);
+}
+
+static int
+tls_error_sys(const uschar *prefix, int err, const host_item *host,
+ uschar ** errstr)
+{
+return tls_error(prefix, US strerror(err), host, errstr);
+}
/*************************************************
state the current GnuTLS exim state container
rc the GnuTLS error code, or 0 if it's a local error
when text identifying read or write
- text local error text when ec is 0
+ text local error text when rc is 0
Returns: nothing
*/
static void
record_io_error(exim_gnutls_state_st *state, int rc, uschar *when, uschar *text)
{
-const char *msg;
+const uschar * msg;
+uschar * errstr;
if (rc == GNUTLS_E_FATAL_ALERT_RECEIVED)
- msg = CS string_sprintf("%s: %s", US gnutls_strerror(rc),
+ msg = string_sprintf("A TLS fatal alert has been received: %s",
US gnutls_alert_get_name(gnutls_alert_get(state->session)));
else
- msg = gnutls_strerror(rc);
+ msg = US gnutls_strerror(rc);
-tls_error(when, msg, state->host);
+(void) tls_error(when, msg, state->host, &errstr);
+
+if (state->host)
+ log_write(0, LOG_MAIN, "H=%s [%s] TLS error on connection %s",
+ state->host->name, state->host->address, errstr);
+else
+ {
+ uschar * conn_info = smtp_get_connection_info();
+ if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5;
+ /* I'd like to get separated H= here, but too hard for now */
+ log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr);
+ }
}
static void
extract_exim_vars_from_tls_state(exim_gnutls_state_st * state)
{
-gnutls_cipher_algorithm_t cipher;
#ifdef HAVE_GNUTLS_SESSION_CHANNEL_BINDING
int old_pool;
int rc;
#endif
tls_support * tlsp = state->tlsp;
-tlsp->active = state->fd_out;
-
-cipher = gnutls_cipher_get(state->session);
-/* returns size in "bytes" */
-tlsp->bits = gnutls_cipher_get_key_size(cipher) * 8;
-
-tlsp->cipher = state->ciphersuite;
+tlsp->active.sock = state->fd_out;
+tlsp->active.tls_ctx = state;
DEBUG(D_tls) debug_printf("cipher: %s\n", state->ciphersuite);
tlsp->certificate_verified = state->peer_cert_verified;
+#ifdef SUPPORT_DANE
+tlsp->dane_verified = state->peer_dane_verified;
+#endif
/* note that tls_channelbinding_b64 is not saved to the spool file, since it's
only available for use for authenticators while this TLS session is running. */
#ifdef HAVE_GNUTLS_SESSION_CHANNEL_BINDING
channel.data = NULL;
channel.size = 0;
-rc = gnutls_session_channel_binding(state->session, GNUTLS_CB_TLS_UNIQUE, &channel);
-if (rc) {
- DEBUG(D_tls) debug_printf("Channel binding error: %s\n", gnutls_strerror(rc));
-} else {
+if ((rc = gnutls_session_channel_binding(state->session, GNUTLS_CB_TLS_UNIQUE, &channel)))
+ { DEBUG(D_tls) debug_printf("Channel binding error: %s\n", gnutls_strerror(rc)); }
+else
+ {
old_pool = store_pool;
store_pool = POOL_PERM;
- tls_channelbinding_b64 = b64encode(channel.data, (int)channel.size);
+ tls_channelbinding_b64 = b64encode(CUS channel.data, (int)channel.size);
store_pool = old_pool;
DEBUG(D_tls) debug_printf("Have channel bindings cached for possible auth usage.\n");
-}
+ }
#endif
/* peercert is set in peer_status() */
*/
static int
-init_server_dh(void)
+init_server_dh(uschar ** errstr)
{
int fd, rc;
unsigned int dh_bits;
size_t sz;
uschar *exp_tls_dhparam;
BOOL use_file_in_spool = FALSE;
-BOOL use_fixed_file = FALSE;
host_item *host = NULL; /* dummy for macros */
DEBUG(D_tls) debug_printf("Initialising GnuTLS server params.\n");
-rc = gnutls_dh_params_init(&dh_server_params);
-exim_gnutls_err_check(US"gnutls_dh_params_init");
+if ((rc = gnutls_dh_params_init(&dh_server_params)))
+ return tls_error_gnu(US"gnutls_dh_params_init", rc, host, errstr);
m.data = NULL;
m.size = 0;
-if (!expand_check(tls_dhparam, US"tls_dhparam", &exp_tls_dhparam))
+if (!expand_check(tls_dhparam, US"tls_dhparam", &exp_tls_dhparam, errstr))
return DEFER;
if (!exp_tls_dhparam)
}
else if (exp_tls_dhparam[0] != '/')
{
- m.data = US std_dh_prime_named(exp_tls_dhparam);
- if (m.data == NULL)
- return tls_error(US"No standard prime named", CS exp_tls_dhparam, NULL);
+ if (!(m.data = US std_dh_prime_named(exp_tls_dhparam)))
+ return tls_error(US"No standard prime named", exp_tls_dhparam, NULL, errstr);
m.size = Ustrlen(m.data);
}
else
- {
- use_fixed_file = TRUE;
filename = exp_tls_dhparam;
- }
if (m.data)
{
- rc = gnutls_dh_params_import_pkcs3(dh_server_params, &m, GNUTLS_X509_FMT_PEM);
- exim_gnutls_err_check(US"gnutls_dh_params_import_pkcs3");
+ if ((rc = gnutls_dh_params_import_pkcs3(dh_server_params, &m, GNUTLS_X509_FMT_PEM)))
+ return tls_error_gnu(US"gnutls_dh_params_import_pkcs3", rc, host, errstr);
DEBUG(D_tls) debug_printf("Loaded fixed standard D-H parameters\n");
return OK;
}
#ifdef HAVE_GNUTLS_SEC_PARAM_CONSTANTS
/* If you change this constant, also change dh_param_fn_ext so that we can use a
different filename and ensure we have sufficient bits. */
-dh_bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, GNUTLS_SEC_PARAM_NORMAL);
-if (!dh_bits)
- return tls_error(US"gnutls_sec_param_to_pk_bits() failed", NULL, NULL);
+
+if (!(dh_bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, GNUTLS_SEC_PARAM_NORMAL)))
+ return tls_error(US"gnutls_sec_param_to_pk_bits() failed", NULL, NULL, errstr);
DEBUG(D_tls)
debug_printf("GnuTLS tells us that for D-H PK, NORMAL is %d bits.\n",
dh_bits);
{
if (!string_format(filename_buf, sizeof(filename_buf),
"%s/gnutls-params-%d", spool_directory, dh_bits))
- return tls_error(US"overlong filename", NULL, NULL);
+ return tls_error(US"overlong filename", NULL, NULL, errstr);
filename = filename_buf;
}
/* Open the cache file for reading and if successful, read it and set up the
parameters. */
-fd = Uopen(filename, O_RDONLY, 0);
-if (fd >= 0)
+if ((fd = Uopen(filename, O_RDONLY, 0)) >= 0)
{
struct stat statbuf;
FILE *fp;
{
saved_errno = errno;
(void)close(fd);
- return tls_error(US"TLS cache stat failed", strerror(saved_errno), NULL);
+ return tls_error_sys(US"TLS cache stat failed", saved_errno, NULL, errstr);
}
if (!S_ISREG(statbuf.st_mode))
{
(void)close(fd);
- return tls_error(US"TLS cache not a file", NULL, NULL);
+ return tls_error(US"TLS cache not a file", NULL, NULL, errstr);
}
if (!(fp = fdopen(fd, "rb")))
{
saved_errno = errno;
(void)close(fd);
- return tls_error(US"fdopen(TLS cache stat fd) failed",
- strerror(saved_errno), NULL);
+ return tls_error_sys(US"fdopen(TLS cache stat fd) failed",
+ saved_errno, NULL, errstr);
}
m.size = statbuf.st_size;
- if (!(m.data = malloc(m.size)))
+ if (!(m.data = store_malloc(m.size)))
{
fclose(fp);
- return tls_error(US"malloc failed", strerror(errno), NULL);
+ return tls_error_sys(US"malloc failed", errno, NULL, errstr);
}
if (!(sz = fread(m.data, m.size, 1, fp)))
{
saved_errno = errno;
fclose(fp);
- free(m.data);
- return tls_error(US"fread failed", strerror(saved_errno), NULL);
+ store_free(m.data);
+ return tls_error_sys(US"fread failed", saved_errno, NULL, errstr);
}
fclose(fp);
rc = gnutls_dh_params_import_pkcs3(dh_server_params, &m, GNUTLS_X509_FMT_PEM);
- free(m.data);
- exim_gnutls_err_check(US"gnutls_dh_params_import_pkcs3");
+ store_free(m.data);
+ if (rc)
+ return tls_error_gnu(US"gnutls_dh_params_import_pkcs3", rc, host, errstr);
DEBUG(D_tls) debug_printf("read D-H parameters from file \"%s\"\n", filename);
}
}
else
return tls_error(string_open_failed(errno, "\"%s\" for reading", filename),
- NULL, NULL);
+ NULL, NULL, errstr);
/* If ret < 0, either the cache file does not exist, or the data it contains
is not useful. One particular case of this is when upgrading from an older
if ((PATH_MAX - Ustrlen(filename)) < 10)
return tls_error(US"Filename too long to generate replacement",
- CS filename, NULL);
+ filename, NULL, errstr);
- temp_fn = string_copy(US "%s.XXXXXXX");
- fd = mkstemp(CS temp_fn); /* modifies temp_fn */
- if (fd < 0)
- return tls_error(US"Unable to open temp file", strerror(errno), NULL);
- (void)fchown(fd, exim_uid, exim_gid); /* Probably not necessary */
+ temp_fn = string_copy(US"%s.XXXXXXX");
+ if ((fd = mkstemp(CS temp_fn)) < 0) /* modifies temp_fn */
+ return tls_error_sys(US"Unable to open temp file", errno, NULL, errstr);
+ (void)exim_chown(temp_fn, exim_uid, exim_gid); /* Probably not necessary */
/* GnuTLS overshoots!
* If we ask for 2236, we might get 2237 or more.
DEBUG(D_tls)
debug_printf("requesting generation of %d bit Diffie-Hellman prime ...\n",
dh_bits_gen);
- rc = gnutls_dh_params_generate2(dh_server_params, dh_bits_gen);
- exim_gnutls_err_check(US"gnutls_dh_params_generate2");
+ if ((rc = gnutls_dh_params_generate2(dh_server_params, dh_bits_gen)))
+ return tls_error_gnu(US"gnutls_dh_params_generate2", rc, host, errstr);
/* gnutls_dh_params_export_pkcs3() will tell us the exact size, every time,
and I confirmed that a NULL call to get the size first is how the GnuTLS
sz = 0;
m.data = NULL;
- rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
- m.data, &sz);
- if (rc != GNUTLS_E_SHORT_MEMORY_BUFFER)
- exim_gnutls_err_check(US"gnutls_dh_params_export_pkcs3(NULL) sizing");
+ if ( (rc = gnutls_dh_params_export_pkcs3(dh_server_params,
+ GNUTLS_X509_FMT_PEM, m.data, &sz))
+ && rc != GNUTLS_E_SHORT_MEMORY_BUFFER)
+ return tls_error_gnu(US"gnutls_dh_params_export_pkcs3(NULL) sizing",
+ rc, host, errstr);
m.size = sz;
- if (!(m.data = malloc(m.size)))
- return tls_error(US"memory allocation failed", strerror(errno), NULL);
+ if (!(m.data = store_malloc(m.size)))
+ return tls_error_sys(US"memory allocation failed", errno, NULL, errstr);
/* this will return a size 1 less than the allocation size above */
- rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
- m.data, &sz);
- if (rc != GNUTLS_E_SUCCESS)
+ if ((rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
+ m.data, &sz)))
{
- free(m.data);
- exim_gnutls_err_check(US"gnutls_dh_params_export_pkcs3() real");
+ store_free(m.data);
+ return tls_error_gnu(US"gnutls_dh_params_export_pkcs3() real", rc, host, errstr);
}
m.size = sz; /* shrink by 1, probably */
- sz = write_to_fd_buf(fd, m.data, (size_t) m.size);
- if (sz != m.size)
+ if ((sz = write_to_fd_buf(fd, m.data, (size_t) m.size)) != m.size)
{
- free(m.data);
- return tls_error(US"TLS cache write D-H params failed",
- strerror(errno), NULL);
+ store_free(m.data);
+ return tls_error_sys(US"TLS cache write D-H params failed",
+ errno, NULL, errstr);
}
- free(m.data);
- sz = write_to_fd_buf(fd, US"\n", 1);
- if (sz != 1)
- return tls_error(US"TLS cache write D-H params final newline failed",
- strerror(errno), NULL);
+ store_free(m.data);
+ if ((sz = write_to_fd_buf(fd, US"\n", 1)) != 1)
+ return tls_error_sys(US"TLS cache write D-H params final newline failed",
+ errno, NULL, errstr);
- rc = close(fd);
- if (rc)
- return tls_error(US"TLS cache write close() failed",
- strerror(errno), NULL);
+ if ((rc = close(fd)))
+ return tls_error_sys(US"TLS cache write close() failed", errno, NULL, errstr);
if (Urename(temp_fn, filename) < 0)
- return tls_error(string_sprintf("failed to rename \"%s\" as \"%s\"",
- temp_fn, filename), strerror(errno), NULL);
+ return tls_error_sys(string_sprintf("failed to rename \"%s\" as \"%s\"",
+ temp_fn, filename), errno, NULL, errstr);
DEBUG(D_tls) debug_printf("wrote D-H parameters to file \"%s\"\n", filename);
}
/* Create and install a selfsigned certificate, for use in server mode */
static int
-tls_install_selfsign(exim_gnutls_state_st * state)
+tls_install_selfsign(exim_gnutls_state_st * state, uschar ** errstr)
{
gnutls_x509_crt_t cert = NULL;
time_t now;
where = US"generating pkey";
if ((rc = gnutls_x509_privkey_generate(pkey, GNUTLS_PK_RSA,
#ifdef SUPPORT_PARAM_TO_PK_BITS
- gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_LOW),
+# ifndef GNUTLS_SEC_PARAM_MEDIUM
+# define GNUTLS_SEC_PARAM_MEDIUM GNUTLS_SEC_PARAM_HIGH
+# endif
+ gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_MEDIUM),
#else
- 1024,
+ 2048,
#endif
0)))
goto err;
where = US"configuring cert";
-now = 0;
+now = 1;
if ( (rc = gnutls_x509_crt_set_version(cert, 3))
|| (rc = gnutls_x509_crt_set_serial(cert, &now, sizeof(now)))
|| (rc = gnutls_x509_crt_set_activation_time(cert, now = time(NULL)))
return rc;
err:
- rc = tls_error(where, gnutls_strerror(rc), NULL);
+ rc = tls_error_gnu(where, rc, NULL, errstr);
goto out;
}
+/* Add certificate and key, from files.
+
+Return:
+ Zero or negative: good. Negate value for certificate index if < 0.
+ Greater than zero: FAIL or DEFER code.
+*/
+
+static int
+tls_add_certfile(exim_gnutls_state_st * state, const host_item * host,
+ uschar * certfile, uschar * keyfile, uschar ** errstr)
+{
+int rc = gnutls_certificate_set_x509_key_file(state->x509_cred,
+ CS certfile, CS keyfile, GNUTLS_X509_FMT_PEM);
+if (rc < 0)
+ return tls_error_gnu(
+ string_sprintf("cert/key setup: cert=%s key=%s", certfile, keyfile),
+ rc, host, errstr);
+return -rc;
+}
+
+
+#if !defined(DISABLE_OCSP) && !defined(SUPPORT_GNUTLS_EXT_RAW_PARSE)
+/* Load an OCSP proof from file for sending by the server. Called
+on getting a status-request handshake message, for earlier versions
+of GnuTLS. */
+
+static int
+server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,
+ gnutls_datum_t * ocsp_response)
+{
+int ret;
+DEBUG(D_tls) debug_printf("OCSP stapling callback: %s\n", US ptr);
+
+if ((ret = gnutls_load_file(ptr, ocsp_response)) < 0)
+ {
+ DEBUG(D_tls) debug_printf("Failed to load ocsp stapling file %s\n",
+ CS ptr);
+ tls_in.ocsp = OCSP_NOT_RESP;
+ return GNUTLS_E_NO_CERTIFICATE_STATUS;
+ }
+
+tls_in.ocsp = OCSP_VFY_NOT_TRIED;
+return 0;
+}
+#endif
+
+
+#ifdef SUPPORT_GNUTLS_EXT_RAW_PARSE
+/* Make a note that we saw a status-request */
+static int
+tls_server_clienthello_ext(void * ctx, unsigned tls_id,
+ const unsigned char *data, unsigned size)
+{
+/* https://www.iana.org/assignments/tls-extensiontype-values/tls-extensiontype-values.xhtml */
+if (tls_id == 5) /* status_request */
+ {
+ DEBUG(D_tls) debug_printf("Seen status_request extension from client\n");
+ tls_in.ocsp = OCSP_NOT_RESP;
+ }
+return 0;
+}
+
+/* Callback for client-hello, on server, if we think we might serve stapled-OCSP */
+static int
+tls_server_clienthello_cb(gnutls_session_t session, unsigned int htype,
+ unsigned when, unsigned int incoming, const gnutls_datum_t * msg)
+{
+/* Call fn for each extension seen. 3.6.3 onwards */
+return gnutls_ext_raw_parse(NULL, tls_server_clienthello_ext, msg,
+ GNUTLS_EXT_RAW_FLAG_TLS_CLIENT_HELLO);
+}
+
+
+/* Make a note that we saw a status-response */
+static int
+tls_server_servercerts_ext(void * ctx, unsigned tls_id,
+ const unsigned char *data, unsigned size)
+{
+/* debug_printf("%s %u\n", __FUNCTION__, tls_id); */
+/* https://www.iana.org/assignments/tls-extensiontype-values/tls-extensiontype-values.xhtml */
+if (FALSE && tls_id == 5) /* status_request */
+ {
+ DEBUG(D_tls) debug_printf("Seen status_request extension\n");
+ tls_in.ocsp = exim_testharness_disable_ocsp_validity_check
+ ? OCSP_VFY_NOT_TRIED : OCSP_VFIED; /* We know that GnuTLS verifies responses */
+ }
+return 0;
+}
+
+/* Callback for certificates packet, on server, if we think we might serve stapled-OCSP */
+static int
+tls_server_servercerts_cb(gnutls_session_t session, unsigned int htype,
+ unsigned when, unsigned int incoming, const gnutls_datum_t * msg)
+{
+/* Call fn for each extension seen. 3.6.3 onwards */
+#ifdef notdef
+/*XXX crashes */
+return gnutls_ext_raw_parse(NULL, tls_server_servercerts_ext, msg, 0);
+#endif
+}
+#endif
+
+/*XXX in tls1.3 the cert-status travel as an extension next to the cert, in the
+ "Handshake Protocol: Certificate" record.
+So we need to spot the Certificate handshake message, parse it and spot any status_request extension(s)
+
+This is different to tls1.2 - where it is a separate record (wireshake term) / handshake message (gnutls term).
+*/
+
+#if defined(EXPERIMENTAL_TLS_RESUME) || defined(SUPPORT_GNUTLS_EXT_RAW_PARSE)
+/* Callback for certificate-status, on server. We sent stapled OCSP. */
+static int
+tls_server_certstatus_cb(gnutls_session_t session, unsigned int htype,
+ unsigned when, unsigned int incoming, const gnutls_datum_t * msg)
+{
+DEBUG(D_tls) debug_printf("Sending certificate-status\n"); /*XXX we get this for tls1.2 but not for 1.3 */
+#ifdef SUPPORT_SRV_OCSP_STACK
+tls_in.ocsp = exim_testharness_disable_ocsp_validity_check
+ ? OCSP_VFY_NOT_TRIED : OCSP_VFIED; /* We know that GnuTLS verifies responses */
+#else
+tls_in.ocsp = OCSP_VFY_NOT_TRIED;
+#endif
+return 0;
+}
+
+/* Callback for handshake messages, on server */
+static int
+tls_server_hook_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg)
+{
+/* debug_printf("%s: htype %u\n", __FUNCTION__, htype); */
+switch (htype)
+ {
+# ifdef SUPPORT_GNUTLS_EXT_RAW_PARSE
+ case GNUTLS_HANDSHAKE_CLIENT_HELLO:
+ return tls_server_clienthello_cb(sess, htype, when, incoming, msg);
+ case GNUTLS_HANDSHAKE_CERTIFICATE_PKT:
+ return tls_server_servercerts_cb(sess, htype, when, incoming, msg);
+# endif
+ case GNUTLS_HANDSHAKE_CERTIFICATE_STATUS:
+ return tls_server_certstatus_cb(sess, htype, when, incoming, msg);
+# ifdef EXPERIMENTAL_TLS_RESUME
+ case GNUTLS_HANDSHAKE_NEW_SESSION_TICKET:
+ return tls_server_ticket_cb(sess, htype, when, incoming, msg);
+# endif
+ default:
+ return 0;
+ }
+}
+#endif
+
+
+#if !defined(DISABLE_OCSP) && defined(SUPPORT_GNUTLS_EXT_RAW_PARSE)
+static void
+tls_server_testharness_ocsp_fiddle(void)
+{
+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("Permitting known bad OCSP response\n");
+ exim_testharness_disable_ocsp_validity_check = TRUE;
+ }
+}
+#endif
+
/*************************************************
* Variables re-expanded post-SNI *
*************************************************/
Arguments:
state exim_gnutls_state_st *
+ errstr error string pointer
Returns: OK/DEFER/FAIL
*/
static int
-tls_expand_session_files(exim_gnutls_state_st *state)
+tls_expand_session_files(exim_gnutls_state_st * state, uschar ** errstr)
{
struct stat statbuf;
int rc;
if (!host) /* server */
if (!state->received_sni)
{
- if (state->tls_certificate &&
- (Ustrstr(state->tls_certificate, US"tls_sni") ||
- Ustrstr(state->tls_certificate, US"tls_in_sni") ||
- Ustrstr(state->tls_certificate, US"tls_out_sni")
- ))
+ if ( state->tls_certificate
+ && ( Ustrstr(state->tls_certificate, US"tls_sni")
+ || Ustrstr(state->tls_certificate, US"tls_in_sni")
+ || Ustrstr(state->tls_certificate, US"tls_out_sni")
+ ) )
{
DEBUG(D_tls) debug_printf("We will re-expand TLS session files if we receive SNI.\n");
state->trigger_sni_changes = TRUE;
saved_tls_crl = state->exp_tls_crl;
}
-rc = gnutls_certificate_allocate_credentials(&state->x509_cred);
-exim_gnutls_err_check(US"gnutls_certificate_allocate_credentials");
+if ((rc = gnutls_certificate_allocate_credentials(&state->x509_cred)))
+ return tls_error_gnu(US"gnutls_certificate_allocate_credentials",
+ rc, host, errstr);
+
+#ifdef SUPPORT_SRV_OCSP_STACK
+gnutls_certificate_set_flags(state->x509_cred, GNUTLS_CERTIFICATE_API_V2);
+
+# if !defined(DISABLE_OCSP) && defined(SUPPORT_GNUTLS_EXT_RAW_PARSE)
+if (!host && tls_ocsp_file)
+ {
+ if (f.running_in_test_harness)
+ tls_server_testharness_ocsp_fiddle();
+
+ if (exim_testharness_disable_ocsp_validity_check)
+ gnutls_certificate_set_flags(state->x509_cred,
+ GNUTLS_CERTIFICATE_API_V2 | GNUTLS_CERTIFICATE_SKIP_OCSP_RESPONSE_CHECK);
+ }
+# endif
+#endif
/* remember: expand_check_tlsvar() is expand_check() but fiddling with
state members, assuming consistent naming; and expand_check() returns
/* check if we at least have a certificate, before doing expensive
D-H generation. */
-if (!expand_check_tlsvar(tls_certificate))
+if (!expand_check_tlsvar(tls_certificate, errstr))
return DEFER;
/* certificate is mandatory in server, optional in client */
|| !*state->exp_tls_certificate
)
if (!host)
- return tls_install_selfsign(state);
+ return tls_install_selfsign(state, errstr);
else
DEBUG(D_tls) debug_printf("TLS: no client certificate specified; okay\n");
-if (state->tls_privatekey && !expand_check_tlsvar(tls_privatekey))
+if (state->tls_privatekey && !expand_check_tlsvar(tls_privatekey, errstr))
return DEFER;
/* tls_privatekey is optional, defaulting to same file as certificate */
-if (state->tls_privatekey == NULL || *state->tls_privatekey == '\0')
+if (!state->tls_privatekey || !*state->tls_privatekey)
{
state->tls_privatekey = state->tls_certificate;
state->exp_tls_privatekey = state->exp_tls_certificate;
DEBUG(D_tls) debug_printf("TLS SNI: have a changed cert/key pair.\n");
}
- rc = gnutls_certificate_set_x509_key_file(state->x509_cred,
- CS state->exp_tls_certificate, CS state->exp_tls_privatekey,
- GNUTLS_X509_FMT_PEM);
- exim_gnutls_err_check(
- string_sprintf("cert/key setup: cert=%s key=%s",
- state->exp_tls_certificate, state->exp_tls_privatekey));
- DEBUG(D_tls) debug_printf("TLS: cert/key registered\n");
- } /* tls_certificate */
+ if (!host) /* server */
+ {
+ const uschar * clist = state->exp_tls_certificate;
+ const uschar * klist = state->exp_tls_privatekey;
+ const uschar * olist;
+ int csep = 0, ksep = 0, osep = 0, cnt = 0;
+ uschar * cfile, * kfile, * ofile;
+#ifndef DISABLE_OCSP
+# ifdef SUPPORT_GNUTLS_EXT_RAW_PARSE
+ gnutls_x509_crt_fmt_t ocsp_fmt = GNUTLS_X509_FMT_DER;
+# endif
+ if (!expand_check(tls_ocsp_file, US"tls_ocsp_file", &ofile, errstr))
+ return DEFER;
+ olist = ofile;
+#endif
-/* Set the OCSP stapling server info */
+ while (cfile = string_nextinlist(&clist, &csep, NULL, 0))
+
+ if (!(kfile = string_nextinlist(&klist, &ksep, NULL, 0)))
+ return tls_error(US"cert/key setup: out of keys", NULL, host, errstr);
+ else if (0 < (rc = tls_add_certfile(state, host, cfile, kfile, errstr)))
+ return rc;
+ else
+ {
+ int gnutls_cert_index = -rc;
+ DEBUG(D_tls) debug_printf("TLS: cert/key %d %s registered\n",
+ gnutls_cert_index, cfile);
#ifndef DISABLE_OCSP
-if ( !host /* server */
- && tls_ocsp_file
- )
- {
- if (gnutls_buggy_ocsp)
- {
- DEBUG(D_tls) debug_printf("GnuTLS library is buggy for OCSP; avoiding\n");
+ if (tls_ocsp_file)
+ {
+ /* Set the OCSP stapling server info */
+ if (gnutls_buggy_ocsp)
+ {
+ DEBUG(D_tls)
+ debug_printf("GnuTLS library is buggy for OCSP; avoiding\n");
+ }
+ else if ((ofile = string_nextinlist(&olist, &osep, NULL, 0)))
+ {
+ DEBUG(D_tls) debug_printf("OCSP response file %d = %s\n",
+ gnutls_cert_index, ofile);
+# ifdef SUPPORT_GNUTLS_EXT_RAW_PARSE
+ if (Ustrncmp(ofile, US"PEM ", 4) == 0)
+ {
+ ocsp_fmt = GNUTLS_X509_FMT_PEM;
+ ofile += 4;
+ }
+ else if (Ustrncmp(ofile, US"DER ", 4) == 0)
+ {
+ ocsp_fmt = GNUTLS_X509_FMT_DER;
+ ofile += 4;
+ }
+
+ if ((rc = gnutls_certificate_set_ocsp_status_request_file2(
+ state->x509_cred, CCS ofile, gnutls_cert_index,
+ ocsp_fmt)) < 0)
+ return tls_error_gnu(
+ US"gnutls_certificate_set_ocsp_status_request_file2",
+ rc, host, errstr);
+ DEBUG(D_tls)
+ debug_printf(" %d response%s loaded\n", rc, rc>1 ? "s":"");
+
+ /* Arrange callbacks for OCSP request observability */
+
+ gnutls_handshake_set_hook_function(state->session,
+ GNUTLS_HANDSHAKE_ANY, GNUTLS_HOOK_POST, tls_server_hook_cb);
+
+# else
+# if defined(SUPPORT_SRV_OCSP_STACK)
+ if ((rc = gnutls_certificate_set_ocsp_status_request_function2(
+ state->x509_cred, gnutls_cert_index,
+ server_ocsp_stapling_cb, ofile)))
+ return tls_error_gnu(
+ US"gnutls_certificate_set_ocsp_status_request_function2",
+ rc, host, errstr);
+ else
+# endif
+ {
+ if (cnt++ > 0)
+ {
+ DEBUG(D_tls)
+ debug_printf("oops; multiple OCSP files not supported\n");
+ break;
+ }
+ gnutls_certificate_set_ocsp_status_request_function(
+ state->x509_cred, server_ocsp_stapling_cb, ofile);
+ }
+# endif /* SUPPORT_GNUTLS_EXT_RAW_PARSE */
+ }
+ else
+ DEBUG(D_tls) debug_printf("ran out of OCSP response files in list\n");
+ }
+#endif /* DISABLE_OCSP */
+ }
}
- else
+ else /* client */
{
- if (!expand_check(tls_ocsp_file, US"tls_ocsp_file",
- &state->exp_tls_ocsp_file))
- return DEFER;
-
- /* Use the full callback method for stapling just to get observability.
- More efficient would be to read the file once only, if it never changed
- (due to SNI). Would need restart on file update, or watch datestamp. */
-
- gnutls_certificate_set_ocsp_status_request_function(state->x509_cred,
- server_ocsp_stapling_cb, state->exp_tls_ocsp_file);
-
- DEBUG(D_tls) debug_printf("OCSP response file = %s\n", state->exp_tls_ocsp_file);
+ if (0 < (rc = tls_add_certfile(state, host,
+ state->exp_tls_certificate, state->exp_tls_privatekey, errstr)))
+ return rc;
+ DEBUG(D_tls) debug_printf("TLS: cert/key registered\n");
}
- }
-#endif
+
+ } /* tls_certificate */
/* Set the trusted CAs file if one is provided, and then add the CRL if one is
if (state->tls_verify_certificates && *state->tls_verify_certificates)
{
- if (!expand_check_tlsvar(tls_verify_certificates))
+ if (!expand_check_tlsvar(tls_verify_certificates, errstr))
return DEFER;
#ifndef SUPPORT_SYSDEFAULT_CABUNDLE
if (Ustrcmp(state->exp_tls_verify_certificates, "system") == 0)
state->exp_tls_verify_certificates = NULL;
#endif
if (state->tls_crl && *state->tls_crl)
- if (!expand_check_tlsvar(tls_crl))
+ if (!expand_check_tlsvar(tls_crl, errstr))
return DEFER;
if (!(state->exp_tls_verify_certificates &&
{
if (Ustat(state->exp_tls_verify_certificates, &statbuf) < 0)
{
- log_write(0, LOG_MAIN|LOG_PANIC, "could not stat %s "
+ log_write(0, LOG_MAIN|LOG_PANIC, "could not stat '%s' "
"(tls_verify_certificates): %s", state->exp_tls_verify_certificates,
strerror(errno));
return DEFER;
#endif
gnutls_certificate_set_x509_trust_file(state->x509_cred,
CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM);
+
+#ifdef SUPPORT_CA_DIR
+ /* Mimic the behaviour with OpenSSL of not advertising a usable-cert list
+ when using the directory-of-certs config model. */
+
+ if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
+ gnutls_certificate_send_x509_rdn_sequence(state->session, 1);
+#endif
}
if (cert_count < 0)
- {
- rc = cert_count;
- exim_gnutls_err_check(US"setting certificate trust");
- }
-DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", cert_count);
+ return tls_error_gnu(US"setting certificate trust", cert_count, host, errstr);
+DEBUG(D_tls)
+ debug_printf("Added %d certificate authorities.\n", cert_count);
if (state->tls_crl && *state->tls_crl &&
state->exp_tls_crl && *state->exp_tls_crl)
{
DEBUG(D_tls) debug_printf("loading CRL file = %s\n", state->exp_tls_crl);
- cert_count = gnutls_certificate_set_x509_crl_file(state->x509_cred,
- CS state->exp_tls_crl, GNUTLS_X509_FMT_PEM);
- if (cert_count < 0)
- {
- rc = cert_count;
- exim_gnutls_err_check(US"gnutls_certificate_set_x509_crl_file");
- }
+ if ((cert_count = gnutls_certificate_set_x509_crl_file(state->x509_cred,
+ CS state->exp_tls_crl, GNUTLS_X509_FMT_PEM)) < 0)
+ return tls_error_gnu(US"gnutls_certificate_set_x509_crl_file",
+ cert_count, host, errstr);
+
DEBUG(D_tls) debug_printf("Processed %d CRLs.\n", cert_count);
}
Arguments:
state exim_gnutls_state_st *
+ errstr error string pointer
Returns: OK/DEFER/FAIL
*/
static int
-tls_set_remaining_x509(exim_gnutls_state_st *state)
+tls_set_remaining_x509(exim_gnutls_state_st *state, uschar ** errstr)
{
int rc;
const host_item *host = state->host; /* macro should be reconsidered? */
if (!state->host)
{
if (!dh_server_params)
- {
- rc = init_server_dh();
- if (rc != OK) return rc;
- }
+ if ((rc = init_server_dh(errstr)) != OK) return rc;
gnutls_certificate_set_dh_params(state->x509_cred, dh_server_params);
}
/* Link the credentials to the session. */
-rc = gnutls_credentials_set(state->session, GNUTLS_CRD_CERTIFICATE, state->x509_cred);
-exim_gnutls_err_check(US"gnutls_credentials_set");
+if ((rc = gnutls_credentials_set(state->session,
+ GNUTLS_CRD_CERTIFICATE, state->x509_cred)))
+ return tls_error_gnu(US"gnutls_credentials_set", rc, host, errstr);
return OK;
}
crl CRL file
require_ciphers tls_require_ciphers setting
caller_state returned state-info structure
+ errstr error string pointer
Returns: OK/DEFER/FAIL
*/
const uschar *cas,
const uschar *crl,
const uschar *require_ciphers,
- exim_gnutls_state_st **caller_state)
+ exim_gnutls_state_st **caller_state,
+ tls_support * tlsp,
+ uschar ** errstr)
{
-exim_gnutls_state_st *state;
+exim_gnutls_state_st * state;
int rc;
size_t sz;
-const char *errpos;
-uschar *p;
-BOOL want_default_priorities;
+const char * errpos;
+const uschar * p;
if (!exim_gnutls_base_init_done)
{
environment variables are used and so breaks for users calling mailq.
To prevent this, we init PKCS11 first, which is the documented approach. */
if (!gnutls_allow_auto_pkcs11)
- {
- rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL);
- exim_gnutls_err_check(US"gnutls_pkcs11_init");
- }
+ if ((rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL)))
+ return tls_error_gnu(US"gnutls_pkcs11_init", rc, host, errstr);
#endif
- rc = gnutls_global_init();
- exim_gnutls_err_check(US"gnutls_global_init");
+ if ((rc = gnutls_global_init()))
+ return tls_error_gnu(US"gnutls_global_init", rc, host, errstr);
#if EXIM_GNUTLS_LIBRARY_LOG_LEVEL >= 0
DEBUG(D_tls)
{
gnutls_global_set_log_function(exim_gnutls_logger_cb);
- /* arbitrarily chosen level; bump upto 9 for more */
+ /* arbitrarily chosen level; bump up to 9 for more */
gnutls_global_set_log_level(EXIM_GNUTLS_LIBRARY_LOG_LEVEL);
}
#endif
if (host)
{
- state = &state_client;
+ /* For client-side sessions we allocate a context. This lets us run
+ several in parallel. */
+ int old_pool = store_pool;
+ store_pool = POOL_PERM;
+ state = store_get(sizeof(exim_gnutls_state_st), FALSE);
+ store_pool = old_pool;
+
memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
- state->tlsp = &tls_out;
+ state->tlsp = tlsp;
DEBUG(D_tls) debug_printf("initialising GnuTLS client session\n");
rc = gnutls_init(&state->session, GNUTLS_CLIENT);
}
{
state = &state_server;
memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
- state->tlsp = &tls_in;
+ state->tlsp = tlsp;
DEBUG(D_tls) debug_printf("initialising GnuTLS server session\n");
rc = gnutls_init(&state->session, GNUTLS_SERVER);
}
-exim_gnutls_err_check(US"gnutls_init");
+if (rc)
+ return tls_error_gnu(US"gnutls_init", rc, host, errstr);
state->host = host;
DEBUG(D_tls)
debug_printf("Expanding various TLS configuration options for session credentials.\n");
-rc = tls_expand_session_files(state);
-if (rc != OK) return rc;
+if ((rc = tls_expand_session_files(state, errstr)) != OK) return rc;
/* These are all other parts of the x509_cred handling, since SNI in GnuTLS
requires a new structure afterwards. */
-rc = tls_set_remaining_x509(state);
-if (rc != OK) return rc;
+if ((rc = tls_set_remaining_x509(state, errstr)) != OK) return rc;
/* set SNI in client, only */
if (host)
{
- if (!expand_check(sni, US"tls_out_sni", &state->tlsp->sni))
+ if (!expand_check(sni, US"tls_out_sni", &state->tlsp->sni, errstr))
return DEFER;
if (state->tlsp->sni && *state->tlsp->sni)
{
DEBUG(D_tls)
debug_printf("Setting TLS client SNI to \"%s\"\n", state->tlsp->sni);
sz = Ustrlen(state->tlsp->sni);
- rc = gnutls_server_name_set(state->session,
- GNUTLS_NAME_DNS, state->tlsp->sni, sz);
- exim_gnutls_err_check(US"gnutls_server_name_set");
+ if ((rc = gnutls_server_name_set(state->session,
+ GNUTLS_NAME_DNS, state->tlsp->sni, sz)))
+ return tls_error_gnu(US"gnutls_server_name_set", rc, host, errstr);
}
}
else if (state->tls_sni)
DEBUG(D_tls) debug_printf("*** PROBABLY A BUG *** " \
- "have an SNI set for a client [%s]\n", state->tls_sni);
+ "have an SNI set for a server [%s]\n", state->tls_sni);
/* This is the priority string support,
http://www.gnutls.org/manual/html_node/Priority-Strings.html
This was backwards incompatible, but means Exim no longer needs to track
all algorithms and provide string forms for them. */
-want_default_priorities = TRUE;
-
+p = NULL;
if (state->tls_require_ciphers && *state->tls_require_ciphers)
{
- if (!expand_check_tlsvar(tls_require_ciphers))
+ if (!expand_check_tlsvar(tls_require_ciphers, errstr))
return DEFER;
if (state->exp_tls_require_ciphers && *state->exp_tls_require_ciphers)
{
- DEBUG(D_tls) debug_printf("GnuTLS session cipher/priority \"%s\"\n",
- state->exp_tls_require_ciphers);
-
- rc = gnutls_priority_init(&state->priority_cache,
- CS state->exp_tls_require_ciphers, &errpos);
- want_default_priorities = FALSE;
p = state->exp_tls_require_ciphers;
+ DEBUG(D_tls) debug_printf("GnuTLS session cipher/priority \"%s\"\n", p);
}
}
-if (want_default_priorities)
+if (!p)
{
+ p = exim_default_gnutls_priority;
DEBUG(D_tls)
- debug_printf("GnuTLS using default session cipher/priority \"%s\"\n",
- exim_default_gnutls_priority);
- rc = gnutls_priority_init(&state->priority_cache,
- exim_default_gnutls_priority, &errpos);
- p = US exim_default_gnutls_priority;
+ debug_printf("GnuTLS using default session cipher/priority \"%s\"\n", p);
}
-exim_gnutls_err_check(string_sprintf(
- "gnutls_priority_init(%s) failed at offset %ld, \"%.6s..\"",
- p, errpos - CS p, errpos));
+if ((rc = gnutls_priority_init(&state->priority_cache, CCS p, &errpos)))
+ return tls_error_gnu(string_sprintf(
+ "gnutls_priority_init(%s) failed at offset %ld, \"%.6s..\"",
+ p, errpos - CS p, errpos),
+ rc, host, errstr);
+
+if ((rc = gnutls_priority_set(state->session, state->priority_cache)))
+ return tls_error_gnu(US"gnutls_priority_set", rc, host, errstr);
-rc = gnutls_priority_set(state->session, state->priority_cache);
-exim_gnutls_err_check(US"gnutls_priority_set");
+/* This also sets the server ticket expiration time to the same, and
+the STEK rotation time to 3x. */
gnutls_db_set_cache_expiration(state->session, ssl_session_timeout);
* Extract peer information *
*************************************************/
+static const uschar *
+cipher_stdname_kcm(gnutls_kx_algorithm_t kx, gnutls_cipher_algorithm_t cipher,
+ gnutls_mac_algorithm_t mac)
+{
+uschar cs_id[2];
+gnutls_kx_algorithm_t kx_i;
+gnutls_cipher_algorithm_t cipher_i;
+gnutls_mac_algorithm_t mac_i;
+
+for (size_t i = 0;
+ gnutls_cipher_suite_info(i, cs_id, &kx_i, &cipher_i, &mac_i, NULL);
+ i++)
+ if (kx_i == kx && cipher_i == cipher && mac_i == mac)
+ return cipher_stdname(cs_id[0], cs_id[1]);
+return NULL;
+}
+
+
+
/* Called from both server and client code.
Only this is allowed to set state->peerdn and state->have_set_peerdn
and we use that to detect double-calls.
Arguments:
state exim_gnutls_state_st *
+ errstr pointer to error string
Returns: OK/DEFER/FAIL
*/
static int
-peer_status(exim_gnutls_state_st *state)
+peer_status(exim_gnutls_state_st * state, uschar ** errstr)
{
-uschar cipherbuf[256];
-const gnutls_datum_t *cert_list;
+gnutls_session_t session = state->session;
+const gnutls_datum_t * cert_list;
int old_pool, rc;
unsigned int cert_list_size = 0;
gnutls_protocol_t protocol;
gnutls_mac_algorithm_t mac;
gnutls_certificate_type_t ct;
gnutls_x509_crt_t crt;
-uschar *p, *dn_buf;
+uschar * dn_buf;
size_t sz;
if (state->have_set_peerdn)
state->peerdn = NULL;
/* tls_cipher */
-cipher = gnutls_cipher_get(state->session);
-protocol = gnutls_protocol_get_version(state->session);
-mac = gnutls_mac_get(state->session);
-kx = gnutls_kx_get(state->session);
-
-string_format(cipherbuf, sizeof(cipherbuf),
- "%s:%s:%d",
- gnutls_protocol_get_name(protocol),
- gnutls_cipher_suite_get_name(kx, cipher, mac),
- (int) gnutls_cipher_get_key_size(cipher) * 8);
-
-/* I don't see a way that spaces could occur, in the current GnuTLS
-code base, but it was a concern in the old code and perhaps older GnuTLS
-releases did return "TLS 1.0"; play it safe, just in case. */
-for (p = cipherbuf; *p != '\0'; ++p)
- if (isspace(*p))
- *p = '-';
+cipher = gnutls_cipher_get(session);
+protocol = gnutls_protocol_get_version(session);
+mac = gnutls_mac_get(session);
+kx =
+#ifdef GNUTLS_TLS1_3
+ protocol >= GNUTLS_TLS1_3 ? 0 :
+#endif
+ gnutls_kx_get(session);
+
old_pool = store_pool;
-store_pool = POOL_PERM;
-state->ciphersuite = string_copy(cipherbuf);
+ {
+ tls_support * tlsp = state->tlsp;
+ store_pool = POOL_PERM;
+
+#ifdef SUPPORT_GNUTLS_SESS_DESC
+ {
+ gstring * g = NULL;
+ uschar * s = US gnutls_session_get_desc(session), c;
+
+ /* Nikos M suggests we use this by preference. It returns like:
+ (TLS1.3)-(ECDHE-SECP256R1)-(RSA-PSS-RSAE-SHA256)-(AES-256-GCM)
+
+ For partial back-compat, put a colon after the TLS version, replace the
+ )-( grouping with __, replace in-group - with _ and append the :keysize. */
+
+ /* debug_printf("peer_status: gnutls_session_get_desc %s\n", s); */
+
+ for (s++; (c = *s) && c != ')'; s++) g = string_catn(g, s, 1);
+ g = string_catn(g, US":", 1);
+ if (*s) s++; /* now on _ between groups */
+ while ((c = *s))
+ {
+ for (*++s && ++s; (c = *s) && c != ')'; s++) g = string_catn(g, c == '-' ? US"_" : s, 1);
+ /* now on ) closing group */
+ if ((c = *s) && *++s == '-') g = string_catn(g, US"__", 2);
+ /* now on _ between groups */
+ }
+ g = string_catn(g, US":", 1);
+ g = string_cat(g, string_sprintf("%d", (int) gnutls_cipher_get_key_size(cipher) * 8));
+ state->ciphersuite = string_from_gstring(g);
+ }
+#else
+ state->ciphersuite = string_sprintf("%s:%s:%d",
+ gnutls_protocol_get_name(protocol),
+ gnutls_cipher_suite_get_name(kx, cipher, mac),
+ (int) gnutls_cipher_get_key_size(cipher) * 8);
+
+ /* I don't see a way that spaces could occur, in the current GnuTLS
+ code base, but it was a concern in the old code and perhaps older GnuTLS
+ releases did return "TLS 1.0"; play it safe, just in case. */
+
+ for (uschar * p = state->ciphersuite; *p; p++) if (isspace(*p)) *p = '-';
+#endif
+
+/* debug_printf("peer_status: ciphersuite %s\n", state->ciphersuite); */
+
+ tlsp->cipher = state->ciphersuite;
+ tlsp->bits = gnutls_cipher_get_key_size(cipher) * 8;
+
+ tlsp->cipher_stdname = cipher_stdname_kcm(kx, cipher, mac);
+ }
store_pool = old_pool;
-state->tlsp->cipher = state->ciphersuite;
/* tls_peerdn */
-cert_list = gnutls_certificate_get_peers(state->session, &cert_list_size);
+cert_list = gnutls_certificate_get_peers(session, &cert_list_size);
-if (cert_list == NULL || cert_list_size == 0)
+if (!cert_list || cert_list_size == 0)
{
DEBUG(D_tls) debug_printf("TLS: no certificate from peer (%p & %d)\n",
cert_list, cert_list_size);
if (state->verify_requirement >= VERIFY_REQUIRED)
return tls_error(US"certificate verification failed",
- "no certificate received from peer", state->host);
+ US"no certificate received from peer", state->host, errstr);
return OK;
}
-ct = gnutls_certificate_type_get(state->session);
-if (ct != GNUTLS_CRT_X509)
+if ((ct = gnutls_certificate_type_get(session)) != GNUTLS_CRT_X509)
{
- const char *ctn = gnutls_certificate_type_get_name(ct);
+ const uschar * ctn = US gnutls_certificate_type_get_name(ct);
DEBUG(D_tls)
debug_printf("TLS: peer cert not X.509 but instead \"%s\"\n", ctn);
if (state->verify_requirement >= VERIFY_REQUIRED)
return tls_error(US"certificate verification not possible, unhandled type",
- ctn, state->host);
+ ctn, state->host, errstr);
return OK;
}
DEBUG(D_tls) debug_printf("TLS: peer cert problem: %s: %s\n", \
(Label), gnutls_strerror(rc)); \
if (state->verify_requirement >= VERIFY_REQUIRED) \
- return tls_error((Label), gnutls_strerror(rc), state->host); \
+ return tls_error_gnu((Label), rc, state->host, errstr); \
return OK; \
} \
} while (0)
exim_gnutls_peer_err(US"getting size for cert DN failed");
return FAIL; /* should not happen */
}
-dn_buf = store_get_perm(sz);
+dn_buf = store_get_perm(sz, TRUE); /* tainted */
rc = gnutls_x509_crt_get_dn(crt, CS dn_buf, &sz);
exim_gnutls_peer_err(US"failed to extract certificate DN [gnutls_x509_crt_get_dn(cert 0)]");
the peer information, but that's too new for some OSes.
Arguments:
- state exim_gnutls_state_st *
- error where to put an error message
+ state exim_gnutls_state_st *
+ errstr where to put an error message
Returns:
FALSE if the session should be rejected
*/
static BOOL
-verify_certificate(exim_gnutls_state_st *state, const char **error)
+verify_certificate(exim_gnutls_state_st * state, uschar ** errstr)
{
int rc;
-unsigned int verify;
+uint verify;
+
+DEBUG(D_tls) debug_printf("TLS: checking peer certificate\n");
+*errstr = NULL;
+rc = peer_status(state, errstr);
-*error = NULL;
+if (state->verify_requirement == VERIFY_NONE)
+ return TRUE;
-if ((rc = peer_status(state)) != OK)
+if (rc != OK || !state->peerdn)
{
verify = GNUTLS_CERT_INVALID;
- *error = "certificate not supplied";
+ *errstr = US"certificate not supplied";
}
else
- rc = gnutls_certificate_verify_peers2(state->session, &verify);
-
-/* Handle the result of verification. INVALID seems to be set as well
-as REVOKED, but leave the test for both. */
-if (rc < 0 ||
- verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED)
- )
{
- state->peer_cert_verified = FALSE;
- if (!*error)
- *error = verify & GNUTLS_CERT_REVOKED
- ? "certificate revoked" : "certificate invalid";
-
- DEBUG(D_tls)
- debug_printf("TLS certificate verification failed (%s): peerdn=\"%s\"\n",
- *error, state->peerdn ? state->peerdn : US"<unset>");
-
- if (state->verify_requirement >= VERIFY_REQUIRED)
+#ifdef SUPPORT_DANE
+ if (state->verify_requirement == VERIFY_DANE && state->host)
{
- gnutls_alert_send(state->session,
- GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
- return FALSE;
- }
- DEBUG(D_tls)
- debug_printf("TLS verify failure overridden (host in tls_try_verify_hosts)\n");
- }
+ /* Using dane_verify_session_crt() would be easy, as it does it all for us
+ including talking to a DNS resolver. But we want to do that bit ourselves
+ as the testsuite intercepts and fakes its own DNS environment. */
+
+ dane_state_t s;
+ dane_query_t r;
+ uint lsize;
+ const gnutls_datum_t * certlist =
+ gnutls_certificate_get_peers(state->session, &lsize);
+ int usage = tls_out.tlsa_usage;
+
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ /* Split the TLSA records into two sets, TA and EE selectors. Run the
+ dane-verification separately so that we know which selector verified;
+ then we know whether to do name-verification (needed for TA but not EE). */
+
+ if (usage == ((1<<DANESSL_USAGE_DANE_TA) | (1<<DANESSL_USAGE_DANE_EE)))
+ { /* a mixed-usage bundle */
+ int i, j, nrec;
+ const char ** dd;
+ int * ddl;
+
+ for(nrec = 0; state->dane_data_len[nrec]; ) nrec++;
+ nrec++;
+
+ dd = store_get(nrec * sizeof(uschar *), FALSE);
+ ddl = store_get(nrec * sizeof(int), FALSE);
+ nrec--;
+
+ if ((rc = dane_state_init(&s, 0)))
+ goto tlsa_prob;
+
+ for (usage = DANESSL_USAGE_DANE_EE;
+ usage >= DANESSL_USAGE_DANE_TA; usage--)
+ { /* take records with this usage */
+ for (j = i = 0; i < nrec; i++)
+ if (state->dane_data[i][0] == usage)
+ {
+ dd[j] = state->dane_data[i];
+ ddl[j++] = state->dane_data_len[i];
+ }
+ if (j)
+ {
+ dd[j] = NULL;
+ ddl[j] = 0;
+
+ if ((rc = dane_raw_tlsa(s, &r, (char * const *)dd, ddl, 1, 0)))
+ goto tlsa_prob;
+
+ if ((rc = dane_verify_crt_raw(s, certlist, lsize,
+ gnutls_certificate_type_get(state->session),
+ r, 0,
+ usage == DANESSL_USAGE_DANE_EE
+ ? DANE_VFLAG_ONLY_CHECK_EE_USAGE : 0,
+ &verify)))
+ {
+ DEBUG(D_tls)
+ debug_printf("TLSA record problem: %s\n", dane_strerror(rc));
+ }
+ else if (verify == 0) /* verification passed */
+ {
+ usage = 1 << usage;
+ break;
+ }
+ }
+ }
-else
- {
- if (state->exp_tls_verify_cert_hostnames)
- {
- int sep = 0;
- const uschar * list = state->exp_tls_verify_cert_hostnames;
- uschar * name;
- while ((name = string_nextinlist(&list, &sep, NULL, 0)))
- if (gnutls_x509_crt_check_hostname(state->tlsp->peercert, CS name))
- break;
- if (!name)
+ if (rc) goto tlsa_prob;
+ }
+ else
+# endif
{
- DEBUG(D_tls)
- debug_printf("TLS certificate verification failed: cert name mismatch\n");
- if (state->verify_requirement >= VERIFY_REQUIRED)
- {
- gnutls_alert_send(state->session,
- GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
- return FALSE;
- }
- return TRUE;
+ if ( (rc = dane_state_init(&s, 0))
+ || (rc = dane_raw_tlsa(s, &r, state->dane_data, state->dane_data_len,
+ 1, 0))
+ || (rc = dane_verify_crt_raw(s, certlist, lsize,
+ gnutls_certificate_type_get(state->session),
+ r, 0,
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ usage == (1 << DANESSL_USAGE_DANE_EE)
+ ? DANE_VFLAG_ONLY_CHECK_EE_USAGE : 0,
+# else
+ 0,
+# endif
+ &verify))
+ )
+ goto tlsa_prob;
}
- }
- state->peer_cert_verified = TRUE;
- DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=\"%s\"\n",
- state->peerdn ? state->peerdn : US"<unset>");
- }
-state->tlsp->peerdn = state->peerdn;
+ if (verify != 0) /* verification failed */
+ {
+ gnutls_datum_t str;
+ (void) dane_verification_status_print(verify, &str, 0);
+ *errstr = US str.data; /* don't bother to free */
+ goto badcert;
+ }
-return TRUE;
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ /* If a TA-mode TLSA record was used for verification we must additionally
+ verify the cert name (but not the CA chain). For EE-mode, skip it. */
+
+ if (usage & (1 << DANESSL_USAGE_DANE_EE))
+# endif
+ {
+ state->peer_dane_verified = state->peer_cert_verified = TRUE;
+ goto goodcert;
+ }
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ /* Assume that the name on the A-record is the one that should be matching
+ the cert. An alternate view is that the domain part of the email address
+ is also permissible. */
+
+ if (gnutls_x509_crt_check_hostname(state->tlsp->peercert,
+ CS state->host->name))
+ {
+ state->peer_dane_verified = state->peer_cert_verified = TRUE;
+ goto goodcert;
+ }
+# endif
+ }
+#endif /*SUPPORT_DANE*/
+
+ rc = gnutls_certificate_verify_peers2(state->session, &verify);
+ }
+
+/* Handle the result of verification. INVALID is set if any others are. */
+
+if (rc < 0 || verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED))
+ {
+ state->peer_cert_verified = FALSE;
+ if (!*errstr)
+ {
+#ifdef GNUTLS_CERT_VFY_STATUS_PRINT
+ DEBUG(D_tls)
+ {
+ gnutls_datum_t txt;
+
+ if (gnutls_certificate_verification_status_print(verify,
+ gnutls_certificate_type_get(state->session), &txt, 0)
+ == GNUTLS_E_SUCCESS)
+ {
+ debug_printf("%s\n", txt.data);
+ gnutls_free(txt.data);
+ }
+ }
+#endif
+ *errstr = verify & GNUTLS_CERT_REVOKED
+ ? US"certificate revoked" : US"certificate invalid";
+ }
+
+ DEBUG(D_tls)
+ debug_printf("TLS certificate verification failed (%s): peerdn=\"%s\"\n",
+ *errstr, state->peerdn ? state->peerdn : US"<unset>");
+
+ if (state->verify_requirement >= VERIFY_REQUIRED)
+ goto badcert;
+ DEBUG(D_tls)
+ debug_printf("TLS verify failure overridden (host in tls_try_verify_hosts)\n");
+ }
+
+else
+ {
+ /* Client side, check the server's certificate name versus the name on the
+ A-record for the connection we made. What to do for server side - what name
+ to use for client? We document that there is no such checking for server
+ side. */
+
+ if ( state->exp_tls_verify_cert_hostnames
+ && !gnutls_x509_crt_check_hostname(state->tlsp->peercert,
+ CS state->exp_tls_verify_cert_hostnames)
+ )
+ {
+ DEBUG(D_tls)
+ debug_printf("TLS certificate verification failed: cert name mismatch\n");
+ if (state->verify_requirement >= VERIFY_REQUIRED)
+ goto badcert;
+ return TRUE;
+ }
+
+ state->peer_cert_verified = TRUE;
+ DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=\"%s\"\n",
+ state->peerdn ? state->peerdn : US"<unset>");
+ }
+
+goodcert:
+ state->tlsp->peerdn = state->peerdn;
+ return TRUE;
+
+#ifdef SUPPORT_DANE
+tlsa_prob:
+ *errstr = string_sprintf("TLSA record problem: %s",
+ rc == DANE_E_REQUESTED_DATA_NOT_AVAILABLE ? "none usable" : dane_strerror(rc));
+#endif
+
+badcert:
+ gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
+ return FALSE;
}
exim_gnutls_state_st *state = &state_server;
unsigned int sni_type;
int rc, old_pool;
+uschar * dummy_errstr;
rc = gnutls_server_name_get(session, sni_name, &data_len, &sni_type, 0);
if (rc != GNUTLS_E_SUCCESS)
{
- DEBUG(D_tls) {
+ DEBUG(D_tls)
if (rc == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE)
debug_printf("TLS: no SNI presented in handshake.\n");
else
debug_printf("TLS failure: gnutls_server_name_get(): %s [%d]\n",
gnutls_strerror(rc), rc);
- };
return 0;
}
/* We now have a UTF-8 string in sni_name */
old_pool = store_pool;
store_pool = POOL_PERM;
-state->received_sni = string_copyn(US sni_name, data_len);
+state->received_sni = string_copy_taint(US sni_name, TRUE);
store_pool = old_pool;
/* We set this one now so that variable expansions below will work */
if (!state->trigger_sni_changes)
return 0;
-rc = tls_expand_session_files(state);
-if (rc != OK)
+if ((rc = tls_expand_session_files(state, &dummy_errstr)) != OK)
{
/* If the setup of certs/etc failed before handshake, TLS would not have
been offered. The best we can do now is abort. */
return GNUTLS_E_APPLICATION_ERROR_MIN;
}
-rc = tls_set_remaining_x509(state);
+rc = tls_set_remaining_x509(state, &dummy_errstr);
if (rc != OK) return GNUTLS_E_APPLICATION_ERROR_MIN;
return 0;
-#ifndef DISABLE_OCSP
-
-static int
-server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,
- gnutls_datum_t * ocsp_response)
-{
-int ret;
-
-if ((ret = gnutls_load_file(ptr, ocsp_response)) < 0)
- {
- DEBUG(D_tls) debug_printf("Failed to load ocsp stapling file %s\n",
- (char *)ptr);
- tls_in.ocsp = OCSP_NOT_RESP;
- return GNUTLS_E_NO_CERTIFICATE_STATUS;
- }
-
-tls_in.ocsp = OCSP_VFY_NOT_TRIED;
-return 0;
-}
-
-#endif
-
-
#ifndef DISABLE_EVENT
/*
We use this callback to get observability and detail-level control
uschar * yield;
exim_gnutls_state_st * state = gnutls_session_get_ptr(session);
-cert_list = gnutls_certificate_get_peers(session, &cert_list_size);
-if (cert_list)
+if ((cert_list = gnutls_certificate_get_peers(session, &cert_list_size)))
while (cert_list_size--)
{
- rc = import_cert(&cert_list[cert_list_size], &crt);
- if (rc != GNUTLS_E_SUCCESS)
+ if ((rc = import_cert(&cert_list[cert_list_size], &crt)) != GNUTLS_E_SUCCESS)
{
DEBUG(D_tls) debug_printf("TLS: peer cert problem: depth %d: %s\n",
cert_list_size, gnutls_strerror(rc));
#endif
+static gstring *
+ddump(gnutls_datum_t * d)
+{
+gstring * g = string_get((d->size+1) * 2);
+uschar * s = d->data;
+for (unsigned i = d->size; i > 0; i--, s++)
+ {
+ g = string_catn(g, US "0123456789abcdef" + (*s >> 4), 1);
+ g = string_catn(g, US "0123456789abcdef" + (*s & 0xf), 1);
+ }
+return g;
+}
+
+static void
+post_handshake_debug(exim_gnutls_state_st * state)
+{
+#ifdef SUPPORT_GNUTLS_SESS_DESC
+debug_printf("%s\n", gnutls_session_get_desc(state->session));
+#endif
+#ifdef SUPPORT_GNUTLS_KEYLOG
+
+# ifdef EXIM_HAVE_TLS1_3
+if (gnutls_protocol_get_version(state->session) < GNUTLS_TLS1_3)
+#else
+if (TRUE)
+#endif
+ {
+ gnutls_datum_t c, s;
+ gstring * gc, * gs;
+ /* we only want the client random and the master secret */
+ gnutls_session_get_random(state->session, &c, &s);
+ gnutls_session_get_master_secret(state->session, &s);
+ gc = ddump(&c);
+ gs = ddump(&s);
+ debug_printf("CLIENT_RANDOM %.*s %.*s\n", (int)gc->ptr, gc->s, (int)gs->ptr, gs->s);
+ }
+else
+ debug_printf("To get keying info for TLS1.3 is hard:\n"
+ " set environment variable SSLKEYLOGFILE to a filename writable by uid exim\n"
+ " add SSLKEYLOGFILE to keep_environment in the exim config\n"
+ " run exim as root\n"
+ " if using sudo, add SSLKEYLOGFILE to env_keep in /etc/sudoers\n"
+ " (works for TLS1.2 also, and saves cut-paste into file)\n");
+#endif
+}
+
+
+#ifdef EXPERIMENTAL_TLS_RESUME
+static int
+tls_server_ticket_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg)
+{
+DEBUG(D_tls) debug_printf("newticket cb\n");
+tls_in.resumption |= RESUME_CLIENT_REQUESTED;
+return 0;
+}
+
+static void
+tls_server_resume_prehandshake(exim_gnutls_state_st * state)
+{
+/* Should the server offer session resumption? */
+tls_in.resumption = RESUME_SUPPORTED;
+if (verify_check_host(&tls_resumption_hosts) == OK)
+ {
+ int rc;
+ /* GnuTLS appears to not do ticket overlap, but does emit a fresh ticket when
+ an offered resumption is unacceptable. We lose one resumption per ticket
+ lifetime, and sessions cannot be indefinitely re-used. There seems to be no
+ way (3.6.7) of changing the default number of 2 TLS1.3 tickets issued, but at
+ least they go out in a single packet. */
+
+ if (!(rc = gnutls_session_ticket_enable_server(state->session,
+ &server_sessticket_key)))
+ tls_in.resumption |= RESUME_SERVER_TICKET;
+ else
+ DEBUG(D_tls)
+ debug_printf("enabling session tickets: %s\n", US gnutls_strerror(rc));
+
+ /* Try to tell if we see a ticket request */
+ gnutls_handshake_set_hook_function(state->session,
+ GNUTLS_HANDSHAKE_ANY, GNUTLS_HOOK_POST, tls_server_hook_cb);
+ }
+}
+static void
+tls_server_resume_posthandshake(exim_gnutls_state_st * state)
+{
+if (gnutls_session_resumption_requested(state->session))
+ {
+ /* This tells us the client sent a full ticket. We use a
+ callback on session-ticket request, elsewhere, to tell
+ if a client asked for a ticket. */
+
+ tls_in.resumption |= RESUME_CLIENT_SUGGESTED;
+ DEBUG(D_tls) debug_printf("client requested resumption\n");
+ }
+if (gnutls_session_is_resumed(state->session))
+ {
+ tls_in.resumption |= RESUME_USED;
+ DEBUG(D_tls) debug_printf("Session resumed\n");
+ }
+}
+#endif
/* ------------------------------------------------------------------------ */
/* Exported functions */
Arguments:
require_ciphers list of allowed ciphers or NULL
+ errstr pointer to error string
Returns: OK on success
DEFER for errors before the start of the negotiation
- FAIL for errors during the negotation; the server can't
+ FAIL for errors during the negotiation; the server can't
continue running.
*/
int
-tls_server_start(const uschar *require_ciphers)
+tls_server_start(const uschar * require_ciphers, uschar ** errstr)
{
int rc;
-const char *error;
-exim_gnutls_state_st *state = NULL;
+exim_gnutls_state_st * state = NULL;
/* Check for previous activation */
-if (tls_in.active >= 0)
+if (tls_in.active.sock >= 0)
{
- tls_error(US"STARTTLS received after TLS started", "", NULL);
- smtp_printf("554 Already in TLS\r\n");
+ tls_error(US"STARTTLS received after TLS started", US "", NULL, errstr);
+ smtp_printf("554 Already in TLS\r\n", FALSE);
return FAIL;
}
DEBUG(D_tls) debug_printf("initialising GnuTLS as a server\n");
-rc = tls_init(NULL, tls_certificate, tls_privatekey,
+if ((rc = tls_init(NULL, tls_certificate, tls_privatekey,
NULL, tls_verify_certificates, tls_crl,
- require_ciphers, &state);
-if (rc != OK) return rc;
+ require_ciphers, &state, &tls_in, errstr)) != OK) return rc;
+
+#ifdef EXPERIMENTAL_TLS_RESUME
+tls_server_resume_prehandshake(state);
+#endif
/* If this is a host for which certificate verification is mandatory or
optional, set up appropriately. */
if (!state->tlsp->on_connect)
{
- smtp_printf("220 TLS go ahead\r\n");
+ smtp_printf("220 TLS go ahead\r\n", FALSE);
fflush(smtp_out);
}
/* Now negotiate the TLS session. We put our own timer on it, since it seems
-that the GnuTLS library doesn't. */
+that the GnuTLS library doesn't.
+From 3.1.0 there is gnutls_handshake_set_timeout() - but it requires you
+to set (and clear down afterwards) up a pull-timeout callback function that does
+a select, so we're no better off unless avoiding signals becomes an issue. */
gnutls_transport_set_ptr2(state->session,
(gnutls_transport_ptr_t)(long) fileno(smtp_in),
state->fd_out = fileno(smtp_out);
sigalrm_seen = FALSE;
-if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
+if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
do
rc = gnutls_handshake(state->session);
while (rc == GNUTLS_E_AGAIN || rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen);
-alarm(0);
+ALARM_CLR(0);
if (rc != GNUTLS_E_SUCCESS)
{
until the server times out. */
if (sigalrm_seen)
- tls_error(US"gnutls_handshake", "timed out", NULL);
+ {
+ tls_error(US"gnutls_handshake", US"timed out", NULL, errstr);
+ gnutls_db_remove_session(state->session);
+ }
else
{
- tls_error(US"gnutls_handshake", gnutls_strerror(rc), NULL);
- gnutls_alert_send_appropriate(state->session, rc);
+ tls_error_gnu(US"gnutls_handshake", rc, NULL, errstr);
+ (void) gnutls_alert_send_appropriate(state->session, rc);
+ gnutls_deinit(state->session);
+ gnutls_certificate_free_credentials(state->x509_cred);
millisleep(500);
- shutdown(fileno(smtp_out), SHUT_WR);
- for (rc = 1024; fgetc(smtp_in) != EOF && rc > 0; ) rc--; /* drain skt */
+ shutdown(state->fd_out, SHUT_WR);
+ for (int i = 1024; fgetc(smtp_in) != EOF && i > 0; ) i--; /* drain skt */
(void)fclose(smtp_out);
(void)fclose(smtp_in);
smtp_out = smtp_in = NULL;
return FAIL;
}
-DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
+#ifdef EXPERIMENTAL_TLS_RESUME
+tls_server_resume_posthandshake(state);
+#endif
+
+DEBUG(D_tls) post_handshake_debug(state);
/* Verify after the fact */
-if ( state->verify_requirement != VERIFY_NONE
- && !verify_certificate(state, &error))
+if (!verify_certificate(state, errstr))
{
if (state->verify_requirement != VERIFY_OPTIONAL)
{
- tls_error(US"certificate verification failed", error, NULL);
+ (void) tls_error(US"certificate verification failed", *errstr, NULL, errstr);
return FAIL;
}
DEBUG(D_tls)
debug_printf("TLS: continuing on only because verification was optional, after: %s\n",
- error);
+ *errstr);
}
-/* Figure out peer DN, and if authenticated, etc. */
-
-if ((rc = peer_status(state)) != OK) return rc;
-
/* Sets various Exim expansion variables; always safe within server */
extract_exim_vars_from_tls_state(state);
state->xfer_buffer = store_malloc(ssl_xfer_buffer_size);
receive_getc = tls_getc;
+receive_getbuf = tls_getbuf;
receive_get_cache = tls_get_cache;
receive_ungetc = tls_ungetc;
receive_feof = tls_feof;
tls_client_setup_hostname_checks(host_item * host, exim_gnutls_state_st * state,
smtp_transport_options_block * ob)
{
-if (verify_check_given_host(&ob->tls_verify_cert_hostnames, host) == OK)
+if (verify_check_given_host(CUSS &ob->tls_verify_cert_hostnames, host) == OK)
{
state->exp_tls_verify_cert_hostnames =
#ifdef SUPPORT_I18N
}
+
+
+#ifdef SUPPORT_DANE
+/* Given our list of RRs from the TLSA lookup, build a lookup block in
+GnuTLS-DANE's preferred format. Hang it on the state str for later
+use in DANE verification.
+
+We point at the dnsa data not copy it, so it must remain valid until
+after verification is done.*/
+
+static BOOL
+dane_tlsa_load(exim_gnutls_state_st * state, dns_answer * dnsa)
+{
+dns_scan dnss;
+int i;
+const char ** dane_data;
+int * dane_data_len;
+
+i = 1;
+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) i++;
+
+dane_data = store_get(i * sizeof(uschar *), FALSE);
+dane_data_len = store_get(i * sizeof(int), FALSE);
+
+i = 0;
+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)
+ {
+ const uschar * p = rr->data;
+/*XXX need somehow to mark rr and its data as tainted. Doues this mean copying it? */
+ uint8_t usage = p[0], sel = p[1], type = p[2];
+
+ DEBUG(D_tls)
+ debug_printf("TLSA: %d %d %d size %d\n", usage, sel, type, rr->size);
+
+ if ( (usage != DANESSL_USAGE_DANE_TA && usage != DANESSL_USAGE_DANE_EE)
+ || (sel != 0 && sel != 1)
+ )
+ continue;
+ switch(type)
+ {
+ case 0: /* Full: cannot check at present */
+ break;
+ case 1: if (rr->size != 3 + 256/8) continue; /* sha2-256 */
+ break;
+ case 2: if (rr->size != 3 + 512/8) continue; /* sha2-512 */
+ break;
+ default: continue;
+ }
+
+ tls_out.tlsa_usage |= 1<<usage;
+ dane_data[i] = CS p;
+ dane_data_len[i++] = rr->size;
+ }
+
+if (!i) return FALSE;
+
+dane_data[i] = NULL;
+dane_data_len[i] = 0;
+
+state->dane_data = (char * const *)dane_data;
+state->dane_data_len = dane_data_len;
+return TRUE;
+}
+#endif
+
+
+
+#ifdef EXPERIMENTAL_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. Although
+there is a gnutls_session_ticket_enable_client() interface it is
+documented as unnecessary (as of 3.6.7) as "session tickets are emabled
+by deafult". There seems to be no way to disable them, so even hosts not
+enabled by the transport option will be sent a ticket request. We will
+however avoid storing and retrieving session information. */
+
+static void
+tls_retrieve_session(tls_support * tlsp, gnutls_session_t session,
+ host_item * host, smtp_transport_options_block * ob)
+{
+tlsp->resumption = RESUME_SUPPORTED;
+if (verify_check_given_host(CUSS &ob->tls_resumption_hosts, host) == OK)
+ {
+ dbdata_tls_session * dt;
+ int len, rc;
+ open_db dbblock, * dbm_file;
+
+ DEBUG(D_tls)
+ debug_printf("check for resumable session for %s\n", host->address);
+ tlsp->host_resumable = TRUE;
+ tlsp->resumption |= RESUME_CLIENT_REQUESTED;
+ if ((dbm_file = dbfn_open(US"tls", O_RDONLY, &dbblock, FALSE, FALSE)))
+ {
+ /* Key for the db is the IP. We'd like to filter the retrieved session
+ for ticket advisory expiry, but 3.6.1 seems to give no access to that */
+
+ if ((dt = dbfn_read_with_length(dbm_file, host->address, &len)))
+ if (!(rc = gnutls_session_set_data(session,
+ CUS dt->session, (size_t)len - sizeof(dbdata_tls_session))))
+ {
+ DEBUG(D_tls) debug_printf("good session\n");
+ tlsp->resumption |= RESUME_CLIENT_SUGGESTED;
+ }
+ else DEBUG(D_tls) debug_printf("setting session resumption data: %s\n",
+ US gnutls_strerror(rc));
+ dbfn_close(dbm_file);
+ }
+ }
+}
+
+
+static void
+tls_save_session(tls_support * tlsp, gnutls_session_t session, const host_item * host)
+{
+/* TLS 1.2 - we get both the callback and the direct posthandshake call,
+but this flag is not set until the second. TLS 1.3 it's the other way about.
+Keep both calls as the session data cannot be extracted before handshake
+completes. */
+
+if (gnutls_session_get_flags(session) & GNUTLS_SFLAGS_SESSION_TICKET)
+ {
+ gnutls_datum_t tkt;
+ int rc;
+
+ DEBUG(D_tls) debug_printf("server offered session ticket\n");
+ tlsp->ticket_received = TRUE;
+ tlsp->resumption |= RESUME_SERVER_TICKET;
+
+ if (tlsp->host_resumable)
+ if (!(rc = gnutls_session_get_data2(session, &tkt)))
+ {
+ open_db dbblock, * dbm_file;
+ int dlen = sizeof(dbdata_tls_session) + tkt.size;
+ dbdata_tls_session * dt = store_get(dlen, TRUE);
+
+ DEBUG(D_tls) debug_printf("session data size %u\n", (unsigned)tkt.size);
+ memcpy(dt->session, tkt.data, tkt.size);
+ gnutls_free(tkt.data);
+
+ if ((dbm_file = dbfn_open(US"tls", O_RDWR, &dbblock, FALSE, FALSE)))
+ {
+ /* key for the db is the IP */
+ dbfn_delete(dbm_file, host->address);
+ dbfn_write(dbm_file, host->address, dt, dlen);
+ dbfn_close(dbm_file);
+
+ DEBUG(D_tls)
+ debug_printf("wrote session db (len %u)\n", (unsigned)dlen);
+ }
+ }
+ else DEBUG(D_tls)
+ debug_printf("extract session data: %s\n", US gnutls_strerror(rc));
+ }
+}
+
+
+/* With a TLS1.3 session, the ticket(s) are not seen until
+the first data read is attempted. And there's often two of them.
+Pick them up with this callback. We are also called for 1.2
+but we do nothing.
+*/
+static int
+tls_client_ticket_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg)
+{
+exim_gnutls_state_st * state = gnutls_session_get_ptr(sess);
+tls_support * tlsp = state->tlsp;
+
+DEBUG(D_tls) debug_printf("newticket cb\n");
+
+if (!tlsp->ticket_received)
+ tls_save_session(tlsp, sess, state->host);
+return 0;
+}
+
+
+static void
+tls_client_resume_prehandshake(exim_gnutls_state_st * state,
+ tls_support * tlsp, host_item * host,
+ smtp_transport_options_block * ob)
+{
+gnutls_session_set_ptr(state->session, state);
+gnutls_handshake_set_hook_function(state->session,
+ GNUTLS_HANDSHAKE_NEW_SESSION_TICKET, GNUTLS_HOOK_POST, tls_client_ticket_cb);
+
+tls_retrieve_session(tlsp, state->session, host, ob);
+}
+
+static void
+tls_client_resume_posthandshake(exim_gnutls_state_st * state,
+ tls_support * tlsp, host_item * host)
+{
+if (gnutls_session_is_resumed(state->session))
+ {
+ DEBUG(D_tls) debug_printf("Session resumed\n");
+ tlsp->resumption |= RESUME_USED;
+ }
+
+tls_save_session(tlsp, state->session, host);
+}
+#endif /* EXPERIMENTAL_TLS_RESUME */
+
+
/*************************************************
* Start a TLS session in a client *
*************************************************/
/* Called from the smtp transport after STARTTLS has been accepted.
Arguments:
- fd the fd of the connection
- host connected host (for messages)
- addr the first address (not used)
- tb transport (always smtp)
-
-Returns: OK/DEFER/FAIL (because using common functions),
- but for a client, DEFER and FAIL have the same meaning
+ cctx connection context
+ conn_args connection details
+ cookie datum for randomness (not used)
+ tlsp record details of channel configuration here; must be non-NULL
+ errstr error string pointer
+
+Returns: TRUE for success with TLS session context set in smtp context,
+ FALSE on error
*/
-int
-tls_client_start(int fd, host_item *host,
- address_item *addr ARG_UNUSED,
- transport_instance *tb
-#ifdef EXPERIMENTAL_DANE
- , dns_answer * unused_tlsa_dnsa
-#endif
- )
+BOOL
+tls_client_start(client_conn_ctx * cctx, smtp_connect_args * conn_args,
+ void * cookie ARG_UNUSED,
+ tls_support * tlsp, uschar ** errstr)
{
-smtp_transport_options_block *ob =
- (smtp_transport_options_block *)tb->options_block;
+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;
int rc;
-const char *error;
-exim_gnutls_state_st *state = NULL;
+exim_gnutls_state_st * state = NULL;
+uschar * cipher_list = NULL;
+
#ifndef DISABLE_OCSP
BOOL require_ocsp =
- verify_check_given_host(&ob->hosts_require_ocsp, host) == OK;
+ verify_check_given_host(CUSS &ob->hosts_require_ocsp, host) == OK;
BOOL request_ocsp = require_ocsp ? TRUE
- : verify_check_given_host(&ob->hosts_request_ocsp, host) == OK;
+ : verify_check_given_host(CUSS &ob->hosts_request_ocsp, host) == OK;
+#endif
+
+DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", cctx->sock);
+
+#ifdef SUPPORT_DANE
+/* If dane is flagged, have either request or require dane for this host, and
+a TLSA record found. Therefore, dane verify required. Which implies cert must
+be requested and supplied, dane verify must pass, and cert verify irrelevant
+(incl. hostnames), and (caller handled) require_tls */
+
+if (conn_args->dane && ob->dane_require_tls_ciphers)
+ {
+ /* not using expand_check_tlsvar because not yet in state */
+ if (!expand_check(ob->dane_require_tls_ciphers, US"dane_require_tls_ciphers",
+ &cipher_list, errstr))
+ return FALSE;
+ cipher_list = cipher_list && *cipher_list
+ ? ob->dane_require_tls_ciphers : ob->tls_require_ciphers;
+ }
#endif
-DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", fd);
+if (!cipher_list)
+ cipher_list = ob->tls_require_ciphers;
-if ((rc = tls_init(host, ob->tls_certificate, ob->tls_privatekey,
+if (tls_init(host, ob->tls_certificate, ob->tls_privatekey,
ob->tls_sni, ob->tls_verify_certificates, ob->tls_crl,
- ob->tls_require_ciphers, &state)) != OK)
- return rc;
+ cipher_list, &state, tlsp, errstr) != OK)
+ return FALSE;
{
int dh_min_bits = ob->tls_dh_min_bits;
set but both tls_verify_hosts and tls_try_verify_hosts are unset. Check only
the specified host patterns if one of them is defined */
-if ( ( state->exp_tls_verify_certificates
- && !ob->tls_verify_hosts
- && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts)
- )
- || verify_check_given_host(&ob->tls_verify_hosts, host) == OK
- )
+#ifdef SUPPORT_DANE
+if (conn_args->dane && dane_tlsa_load(state, &conn_args->tlsa_dnsa))
+ {
+ DEBUG(D_tls)
+ debug_printf("TLS: server certificate DANE required.\n");
+ state->verify_requirement = VERIFY_DANE;
+ gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE);
+ }
+else
+#endif
+ if ( ( state->exp_tls_verify_certificates
+ && !ob->tls_verify_hosts
+ && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts)
+ )
+ || verify_check_given_host(CUSS &ob->tls_verify_hosts, host) == OK
+ )
{
tls_client_setup_hostname_checks(host, state, ob);
DEBUG(D_tls)
state->verify_requirement = VERIFY_REQUIRED;
gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE);
}
-else if (verify_check_given_host(&ob->tls_try_verify_hosts, host) == OK)
+else if (verify_check_given_host(CUSS &ob->tls_try_verify_hosts, host) == OK)
{
tls_client_setup_hostname_checks(host, state, ob);
DEBUG(D_tls)
DEBUG(D_tls) debug_printf("TLS: will request OCSP stapling\n");
if ((rc = gnutls_ocsp_status_request_enable_client(state->session,
NULL, 0, NULL)) != OK)
- return tls_error(US"cert-status-req",
- gnutls_strerror(rc), state->host);
- tls_out.ocsp = OCSP_NOT_RESP;
+ {
+ tls_error_gnu(US"cert-status-req", rc, state->host, errstr);
+ return FALSE;
+ }
+ tlsp->ocsp = OCSP_NOT_RESP;
}
#endif
+#ifdef EXPERIMENTAL_TLS_RESUME
+tls_client_resume_prehandshake(state, tlsp, host, ob);
+#endif
+
#ifndef DISABLE_EVENT
-if (tb->event_action)
+if (tb && tb->event_action)
{
state->event_action = tb->event_action;
gnutls_session_set_ptr(state->session, state);
}
#endif
-gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr_t)(long) fd);
-state->fd_in = fd;
-state->fd_out = fd;
+gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr_t)(long) cctx->sock);
+state->fd_in = cctx->sock;
+state->fd_out = cctx->sock;
DEBUG(D_tls) debug_printf("about to gnutls_handshake\n");
/* There doesn't seem to be a built-in timeout on connection. */
sigalrm_seen = FALSE;
-alarm(ob->command_timeout);
+ALARM(ob->command_timeout);
do
- {
rc = gnutls_handshake(state->session);
- } while ((rc == GNUTLS_E_AGAIN) ||
- (rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen));
-alarm(0);
+while (rc == GNUTLS_E_AGAIN || rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen);
+ALARM_CLR(0);
if (rc != GNUTLS_E_SUCCESS)
+ {
if (sigalrm_seen)
{
gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_USER_CANCELED);
- return tls_error(US"gnutls_handshake", "timed out", state->host);
+ tls_error(US"gnutls_handshake", US"timed out", state->host, errstr);
}
else
- return tls_error(US"gnutls_handshake", gnutls_strerror(rc), state->host);
+ tls_error_gnu(US"gnutls_handshake", rc, state->host, errstr);
+ return FALSE;
+ }
-DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
+DEBUG(D_tls) post_handshake_debug(state);
/* Verify late */
-if (state->verify_requirement != VERIFY_NONE &&
- !verify_certificate(state, &error))
- return tls_error(US"certificate verification failed", error, state->host);
+if (!verify_certificate(state, errstr))
+ {
+ tls_error(US"certificate verification failed", *errstr, state->host, errstr);
+ return FALSE;
+ }
#ifndef DISABLE_OCSP
-if (require_ocsp)
+if (request_ocsp)
{
DEBUG(D_tls)
{
gnutls_datum_t stapling;
gnutls_ocsp_resp_t resp;
gnutls_datum_t printed;
- if ( (rc= gnutls_ocsp_status_request_get(state->session, &stapling)) == 0
- && (rc= gnutls_ocsp_resp_init(&resp)) == 0
- && (rc= gnutls_ocsp_resp_import(resp, &stapling)) == 0
- && (rc= gnutls_ocsp_resp_print(resp, GNUTLS_OCSP_PRINT_FULL, &printed)) == 0
- )
- {
- debug_printf("%.4096s", printed.data);
- gnutls_free(printed.data);
- }
- else
- (void) tls_error(US"ocsp decode", gnutls_strerror(rc), state->host);
+ unsigned idx = 0;
+
+ for (;
+# ifdef GNUTLS_OCSP_STATUS_REQUEST_GET2
+ (rc = gnutls_ocsp_status_request_get2(state->session, idx, &stapling)) == 0;
+#else
+ (rc = gnutls_ocsp_status_request_get(state->session, &stapling)) == 0;
+#endif
+ idx++)
+ if ( (rc= gnutls_ocsp_resp_init(&resp)) == 0
+ && (rc= gnutls_ocsp_resp_import(resp, &stapling)) == 0
+ && (rc= gnutls_ocsp_resp_print(resp, GNUTLS_OCSP_PRINT_COMPACT, &printed)) == 0
+ )
+ {
+ debug_printf("%.4096s", printed.data);
+ gnutls_free(printed.data);
+ }
+ else
+ (void) tls_error_gnu(US"ocsp decode", rc, state->host, errstr);
+ if (idx == 0 && rc)
+ (void) tls_error_gnu(US"ocsp decode", rc, state->host, errstr);
}
if (gnutls_ocsp_status_request_is_checked(state->session, 0) == 0)
{
- tls_out.ocsp = OCSP_FAILED;
- return tls_error(US"certificate status check failed", NULL, state->host);
+ tlsp->ocsp = OCSP_FAILED;
+ tls_error(US"certificate status check failed", NULL, state->host, errstr);
+ if (require_ocsp)
+ return FALSE;
+ }
+ else
+ {
+ DEBUG(D_tls) debug_printf("Passed OCSP checking\n");
+ tlsp->ocsp = OCSP_VFIED;
}
- DEBUG(D_tls) debug_printf("Passed OCSP checking\n");
- tls_out.ocsp = OCSP_VFIED;
}
#endif
-/* Figure out peer DN, and if authenticated, etc. */
-
-if ((rc = peer_status(state)) != OK)
- return rc;
+#ifdef EXPERIMENTAL_TLS_RESUME
+tls_client_resume_posthandshake(state, tlsp, host);
+#endif
/* Sets various Exim expansion variables; may need to adjust for ACL callouts */
extract_exim_vars_from_tls_state(state);
-return OK;
+cctx->tls_ctx = state;
+return TRUE;
}
daemon, to shut down the TLS library, without actually doing a shutdown (which
would tamper with the TLS session in the parent process).
-Arguments: TRUE if gnutls_bye is to be called
+Arguments:
+ ct_ctx client context pointer, or NULL for the one global server context
+ shutdown 1 if TLS close-alert is to be sent,
+ 2 if also response to be waited for
+
Returns: nothing
*/
void
-tls_close(BOOL is_server, BOOL shutdown)
+tls_close(void * ct_ctx, int shutdown)
{
-exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
+exim_gnutls_state_st * state = ct_ctx ? ct_ctx : &state_server;
+tls_support * tlsp = state->tlsp;
-if (!state->tlsp || state->tlsp->active < 0) return; /* TLS was not active */
+if (!tlsp || tlsp->active.sock < 0) return; /* TLS was not active */
if (shutdown)
{
- DEBUG(D_tls) debug_printf("tls_close() from '%s': shutting down TLS\n");
- gnutls_bye(state->session, GNUTLS_SHUT_WR);
+ DEBUG(D_tls) debug_printf("tls_close(): shutting down TLS%s\n",
+ shutdown > 1 ? " (with response-wait)" : "");
+
+ ALARM(2);
+ gnutls_bye(state->session, shutdown > 1 ? GNUTLS_SHUT_RDWR : GNUTLS_SHUT_WR);
+ ALARM_CLR(0);
+ }
+
+if (!ct_ctx) /* server */
+ {
+ 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;
}
gnutls_deinit(state->session);
+gnutls_certificate_free_credentials(state->x509_cred);
+
+tlsp->active.sock = -1;
+tlsp->active.tls_ctx = NULL;
+/* Leave bits, peercert, cipher, peerdn, certificate_verified set, for logging */
+tls_channelbinding_b64 = NULL;
+
-state->tlsp->active = -1;
+if (state->xfer_buffer) store_free(state->xfer_buffer);
memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
+}
+
+
+
+
+static BOOL
+tls_refill(unsigned lim)
+{
+exim_gnutls_state_st * state = &state_server;
+ssize_t inbytes;
+
+DEBUG(D_tls) debug_printf("Calling gnutls_record_recv(%p, %p, %u)\n",
+ state->session, state->xfer_buffer, ssl_xfer_buffer_size);
+
+sigalrm_seen = FALSE;
+if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
+
+do
+ inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
+ MIN(ssl_xfer_buffer_size, lim));
+while (inbytes == GNUTLS_E_AGAIN);
+
+if (smtp_receive_timeout > 0) ALARM_CLR(0);
-if ((state_server.session == NULL) && (state_client.session == NULL))
+if (had_command_timeout) /* set by signal handler */
+ smtp_command_timeout_exit(); /* does not return */
+if (had_command_sigterm)
+ smtp_command_sigterm_exit();
+if (had_data_timeout)
+ smtp_data_timeout_exit();
+if (had_data_sigint)
+ smtp_data_sigint_exit();
+
+/* Timeouts do not get this far. A zero-byte return appears to mean that the
+TLS session has been closed down, not that the socket itself has been closed
+down. Revert to non-TLS handling. */
+
+if (sigalrm_seen)
{
- gnutls_global_deinit();
- exim_gnutls_base_init_done = FALSE;
+ DEBUG(D_tls) debug_printf("Got tls read timeout\n");
+ state->xfer_error = TRUE;
+ return FALSE;
}
-}
-
+else if (inbytes == 0)
+ {
+ DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
+ tls_close(NULL, TLS_NO_SHUTDOWN);
+ return FALSE;
+ }
+/* Handle genuine errors */
+else if (inbytes < 0)
+ {
+ DEBUG(D_tls) debug_printf("%s: err from gnutls_record_recv\n", __FUNCTION__);
+ record_io_error(state, (int) inbytes, US"recv", NULL);
+ state->xfer_error = TRUE;
+ return FALSE;
+ }
+#ifndef DISABLE_DKIM
+dkim_exim_verify_feed(state->xfer_buffer, inbytes);
+#endif
+state->xfer_buffer_hwm = (int) inbytes;
+state->xfer_buffer_lwm = 0;
+return TRUE;
+}
/*************************************************
* TLS version of getc *
This feeds DKIM and should be used for all message-body reads.
-Arguments: none
+Arguments: lim Maximum amount to read/buffer
Returns: the next character or EOF
*/
int
-tls_getc(void)
+tls_getc(unsigned lim)
{
-exim_gnutls_state_st *state = &state_server;
-if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
- {
- ssize_t inbytes;
-
- DEBUG(D_tls) debug_printf("Calling gnutls_record_recv(%p, %p, %u)\n",
- state->session, state->xfer_buffer, ssl_xfer_buffer_size);
-
- if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
- inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
- ssl_xfer_buffer_size);
- alarm(0);
-
- /* Timeouts do not get this far; see command_timeout_handler().
- A zero-byte return appears to mean that the TLS session has been
- closed down, not that the socket itself has been closed down. Revert to
- non-TLS handling. */
-
- if (sigalrm_seen)
- {
- DEBUG(D_tls) debug_printf("Got tls read timeout\n");
- state->xfer_error = 1;
- return EOF;
- }
+exim_gnutls_state_st * state = &state_server;
- else if (inbytes == 0)
- {
- DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
+if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
+ if (!tls_refill(lim))
+ return state->xfer_error ? EOF : smtp_getc(lim);
- receive_getc = smtp_getc;
- receive_get_cache = smtp_get_cache;
- receive_ungetc = smtp_ungetc;
- receive_feof = smtp_feof;
- receive_ferror = smtp_ferror;
- receive_smtp_buffered = smtp_buffered;
+/* Something in the buffer; return next uschar */
- gnutls_deinit(state->session);
- state->session = NULL;
- state->tlsp->active = -1;
- state->tlsp->bits = 0;
- state->tlsp->certificate_verified = FALSE;
- tls_channelbinding_b64 = NULL;
- state->tlsp->cipher = NULL;
- state->tlsp->peercert = NULL;
- state->tlsp->peerdn = NULL;
-
- return smtp_getc();
- }
+return state->xfer_buffer[state->xfer_buffer_lwm++];
+}
- /* Handle genuine errors */
+uschar *
+tls_getbuf(unsigned * len)
+{
+exim_gnutls_state_st * state = &state_server;
+unsigned size;
+uschar * buf;
- else if (inbytes < 0)
+if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
+ if (!tls_refill(*len))
{
- record_io_error(state, (int) inbytes, US"recv", NULL);
- state->xfer_error = 1;
- return EOF;
+ if (!state->xfer_error) return smtp_getbuf(len);
+ *len = 0;
+ return NULL;
}
-#ifndef DISABLE_DKIM
- dkim_exim_verify_feed(state->xfer_buffer, inbytes);
-#endif
- state->xfer_buffer_hwm = (int) inbytes;
- state->xfer_buffer_lwm = 0;
- }
-/* Something in the buffer; return next uschar */
-
-return state->xfer_buffer[state->xfer_buffer_lwm++];
+if ((size = state->xfer_buffer_hwm - state->xfer_buffer_lwm) > *len)
+ size = *len;
+buf = &state->xfer_buffer[state->xfer_buffer_lwm];
+state->xfer_buffer_lwm += size;
+*len = size;
+return buf;
}
+
void
tls_get_cache()
{
}
+BOOL
+tls_could_read(void)
+{
+return state_server.xfer_buffer_lwm < state_server.xfer_buffer_hwm
+ || gnutls_record_check_pending(state_server.session) > 0;
+}
+
+
/*************************************************
then the caller must feed DKIM.
Arguments:
+ ct_ctx client context pointer, or NULL for the one global server context
buff buffer of data
len size of buffer
Returns: the number of bytes read
- -1 after a failed read
+ -1 after a failed read, including EOF
*/
int
-tls_read(BOOL is_server, uschar *buff, size_t len)
+tls_read(void * ct_ctx, uschar *buff, size_t len)
{
-exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
+exim_gnutls_state_st * state = ct_ctx ? ct_ctx : &state_server;
ssize_t inbytes;
if (len > INT_MAX)
debug_printf("Calling gnutls_record_recv(%p, %p, " SIZE_T_FMT ")\n",
state->session, buff, len);
-inbytes = gnutls_record_recv(state->session, buff, len);
+do
+ inbytes = gnutls_record_recv(state->session, buff, len);
+while (inbytes == GNUTLS_E_AGAIN);
+
if (inbytes > 0) return inbytes;
if (inbytes == 0)
{
DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
}
-else record_io_error(state, (int)inbytes, US"recv", NULL);
+else
+ {
+ DEBUG(D_tls) debug_printf("%s: err from gnutls_record_recv\n", __FUNCTION__);
+ record_io_error(state, (int)inbytes, US"recv", NULL);
+ }
return -1;
}
/*
Arguments:
- is_server channel specifier
+ ct_ctx client context pointer, or NULL for the one global server context
buff buffer of data
len number of bytes
+ more more data expected soon
Returns: the number of bytes after a successful write,
-1 after a failed write
*/
int
-tls_write(BOOL is_server, const uschar *buff, size_t len)
+tls_write(void * ct_ctx, const uschar * buff, size_t len, BOOL more)
{
ssize_t outbytes;
size_t left = len;
-exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
+exim_gnutls_state_st * state = ct_ctx ? ct_ctx : &state_server;
+#ifdef SUPPORT_CORK
+static BOOL corked = FALSE;
+
+if (more && !corked) gnutls_record_cork(state->session);
+#endif
+
+DEBUG(D_tls) debug_printf("%s(%p, " SIZE_T_FMT "%s)\n", __FUNCTION__,
+ buff, left, more ? ", more" : "");
-DEBUG(D_tls) debug_printf("tls_do_write(%p, " SIZE_T_FMT ")\n", buff, left);
while (left > 0)
{
DEBUG(D_tls) debug_printf("gnutls_record_send(SSL, %p, " SIZE_T_FMT ")\n",
buff, left);
- outbytes = gnutls_record_send(state->session, buff, left);
+
+ do
+ outbytes = gnutls_record_send(state->session, buff, left);
+ while (outbytes == GNUTLS_E_AGAIN);
DEBUG(D_tls) debug_printf("outbytes=" SSIZE_T_FMT "\n", outbytes);
if (outbytes < 0)
{
+ DEBUG(D_tls) debug_printf("%s: gnutls_record_send err\n", __FUNCTION__);
record_io_error(state, outbytes, US"send", NULL);
return -1;
}
len = INT_MAX;
}
+#ifdef SUPPORT_CORK
+if (more != corked)
+ {
+ if (!more) (void) gnutls_record_uncork(state->session, 0);
+ corked = more;
+ }
+#endif
+
return (int) len;
}
{
unsigned int r;
int i, needed_len;
-uschar *p;
uschar smallbuf[sizeof(r)];
if (max <= 1)
needed_len = sizeof(r);
/* Don't take 8 times more entropy than needed if int is 8 octets and we were
- * asked for a number less than 10. */
+asked for a number less than 10. */
+
for (r = max, i = 0; r; ++i)
r >>= 1;
i = (i + 7) / 8;
return vaguely_random_number_fallback(max);
}
r = 0;
-for (p = smallbuf; needed_len; --needed_len, ++p)
- {
- r *= 256;
- r += *p;
- }
+for (uschar * p = smallbuf; needed_len; --needed_len, ++p)
+ r = r * 256 + *p;
/* We don't particularly care about weighted results; if someone wants
* smooth distribution and cares enough then they should submit a patch then. */
uschar *expciphers = NULL;
gnutls_priority_t priority_cache;
const char *errpos;
+uschar * dummy_errstr;
#define validate_check_rc(Label) do { \
if (rc != GNUTLS_E_SUCCESS) { if (exim_gnutls_base_init_done) gnutls_global_deinit(); \
if (!(tls_require_ciphers && *tls_require_ciphers))
return_deinit(NULL);
-if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers))
+if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers,
+ &dummy_errstr))
return_deinit(US"failed to expand tls_require_ciphers");
if (!(expciphers && *expciphers))
gnutls_check_version(NULL));
}
+#endif /*!MACRO_PREDEF*/
/* vi: aw ai sw=2
*/
/* End of tls-gnu.c */
git://git.exim.org / exim.git / blobdiff