* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2017 */
+/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */
/* Copyright (c) Phil Pennock 2012 */
#if GNUTLS_VERSION_NUMBER >= 0x030109
# define SUPPORT_CORK
#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030506 && !defined(DISABLE_OCSP)
+# define SUPPORT_SRV_OCSP_STACK
+#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
#ifndef DISABLE_OCSP
# include <gnutls/ocsp.h>
#endif
+#ifdef SUPPORT_DANE
+# include <gnutls/dane.h>
+#endif
/* 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;
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 = {
.fd_in = -1,
.fd_out = -1,
.peer_cert_verified = FALSE,
+ .peer_dane_verified = FALSE,
.trigger_sni_changes =FALSE,
.have_set_peerdn = FALSE,
.host = NULL,
.exp_tls_verify_certificates = NULL,
.exp_tls_crl = NULL,
.exp_tls_require_ciphers = NULL,
- .exp_tls_ocsp_file = NULL,
.exp_tls_verify_cert_hostnames = NULL,
#ifndef DISABLE_EVENT
.event_action = NULL,
.xfer_buffer = NULL,
.xfer_buffer_lwm = 0,
.xfer_buffer_hwm = 0,
- .xfer_eof = 0,
- .xfer_error = 0,
+ .xfer_eof = FALSE,
+ .xfer_error = FALSE,
};
/* Not only do we have our own APIs which don't pass around state, assuming
/* 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. Possibly GNuTLS also looks for an environment variable
+"GNUTLS_DEBUG_LEVEL". */
#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) \
+#define exim_gnutls_err_check(rc, Label) do { \
+ if ((rc) != GNUTLS_E_SUCCESS) \
return tls_error((Label), gnutls_strerror(rc), host, errstr); \
} while (0)
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. */
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");
+exim_gnutls_err_check(rc, US"gnutls_dh_params_init");
m.data = NULL;
m.size = 0;
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");
+ exim_gnutls_err_check(rc, US"gnutls_dh_params_import_pkcs3");
DEBUG(D_tls) debug_printf("Loaded fixed standard D-H parameters\n");
return OK;
}
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");
+ exim_gnutls_err_check(rc, US"gnutls_dh_params_import_pkcs3");
DEBUG(D_tls) debug_printf("read D-H parameters from file \"%s\"\n", filename);
}
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");
+ exim_gnutls_err_check(rc, US"gnutls_dh_params_generate2");
/* 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
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");
+ exim_gnutls_err_check(rc, US"gnutls_dh_params_export_pkcs3(NULL) sizing");
m.size = sz;
if (!(m.data = malloc(m.size)))
return tls_error(US"memory allocation failed", strerror(errno), NULL, errstr);
if (rc != GNUTLS_E_SUCCESS)
{
free(m.data);
- exim_gnutls_err_check(US"gnutls_dh_params_export_pkcs3() real");
+ exim_gnutls_err_check(rc, US"gnutls_dh_params_export_pkcs3() real");
}
m.size = sz; /* shrink by 1, probably */
+/* 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(
+ string_sprintf("cert/key setup: cert=%s key=%s", certfile, keyfile),
+ gnutls_strerror(rc), host, errstr);
+return -rc;
+}
+
+
/*************************************************
* Variables re-expanded post-SNI *
*************************************************/
*/
static int
-tls_expand_session_files(exim_gnutls_state_st *state, uschar ** errstr)
+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;
}
rc = gnutls_certificate_allocate_credentials(&state->x509_cred);
-exim_gnutls_err_check(US"gnutls_certificate_allocate_credentials");
+exim_gnutls_err_check(rc, US"gnutls_certificate_allocate_credentials");
+
+#ifdef SUPPORT_SRV_OCSP_STACK
+gnutls_certificate_set_flags(state->x509_cred, GNUTLS_CERTIFICATE_API_V2);
+#endif
/* remember: expand_check_tlsvar() is expand_check() but fiddling with
state members, assuming consistent naming; and expand_check() returns
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
+ if (!expand_check(tls_ocsp_file, US"tls_ocsp_file", &ofile, errstr))
+ return DEFER;
+ olist = ofile;
+#endif
+ 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 %s registered\n", cfile);
-/* Set the OCSP stapling server info */
+ /* Set the OCSP stapling server info */
#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)
+ 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)))
+ {
+ /* 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. */
+
+# ifdef SUPPORT_SRV_OCSP_STACK
+ rc = gnutls_certificate_set_ocsp_status_request_function2(
+ state->x509_cred, gnutls_cert_index,
+ server_ocsp_stapling_cb, ofile);
+
+ exim_gnutls_err_check(rc,
+ US"gnutls_certificate_set_ocsp_status_request_function2");
+# else
+ 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
+
+ DEBUG(D_tls) debug_printf("OCSP response file = %s\n", ofile);
+ }
+ else
+ DEBUG(D_tls) debug_printf("ran out of OCSP response files in list\n");
+#endif
+ }
}
else
{
- if (!expand_check(tls_ocsp_file, US"tls_ocsp_file",
- &state->exp_tls_ocsp_file, errstr))
- 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 (cert_count < 0)
{
rc = cert_count;
- exim_gnutls_err_check(US"setting certificate trust");
+ exim_gnutls_err_check(rc, US"setting certificate trust");
}
DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", cert_count);
if (cert_count < 0)
{
rc = cert_count;
- exim_gnutls_err_check(US"gnutls_certificate_set_x509_crl_file");
+ exim_gnutls_err_check(rc, US"gnutls_certificate_set_x509_crl_file");
}
DEBUG(D_tls) debug_printf("Processed %d CRLs.\n", cert_count);
}
/* 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");
+exim_gnutls_err_check(rc, US"gnutls_credentials_set");
return OK;
}
if (!gnutls_allow_auto_pkcs11)
{
rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL);
- exim_gnutls_err_check(US"gnutls_pkcs11_init");
+ exim_gnutls_err_check(rc, US"gnutls_pkcs11_init");
}
#endif
rc = gnutls_global_init();
- exim_gnutls_err_check(US"gnutls_global_init");
+ exim_gnutls_err_check(rc, US"gnutls_global_init");
#if EXIM_GNUTLS_LIBRARY_LOG_LEVEL >= 0
DEBUG(D_tls)
DEBUG(D_tls) debug_printf("initialising GnuTLS server session\n");
rc = gnutls_init(&state->session, GNUTLS_SERVER);
}
-exim_gnutls_err_check(US"gnutls_init");
+exim_gnutls_err_check(rc, US"gnutls_init");
state->host = host;
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");
+ exim_gnutls_err_check(rc, US"gnutls_server_name_set");
}
}
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
p = US exim_default_gnutls_priority;
}
-exim_gnutls_err_check(string_sprintf(
+exim_gnutls_err_check(rc, string_sprintf(
"gnutls_priority_init(%s) failed at offset %ld, \"%.6s..\"",
p, errpos - CS p, errpos));
rc = gnutls_priority_set(state->session, state->priority_cache);
-exim_gnutls_err_check(US"gnutls_priority_set");
+exim_gnutls_err_check(rc, US"gnutls_priority_set");
gnutls_db_set_cache_expiration(state->session, ssl_session_timeout);
the peer information, but that's too new for some OSes.
Arguments:
- state exim_gnutls_state_st *
- errstr 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, uschar ** errstr)
+verify_certificate(exim_gnutls_state_st * state, uschar ** errstr)
{
int rc;
-unsigned int verify;
+uint verify;
+
+if (state->verify_requirement == VERIFY_NONE)
+ return TRUE;
*errstr = NULL;
*errstr = US"certificate not supplied";
}
else
+
+ {
+#ifdef SUPPORT_DANE
+ if (state->verify_requirement == VERIFY_DANE && state->host)
+ {
+ /* 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 CA-chain-verification and 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 *));
+ ddl = store_get(nrec * sizeof(int));
+ 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;
+ }
+ }
+ }
+
+ if (rc) goto tlsa_prob;
+ }
+ else
+# endif
+ {
+ 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;
+ }
+
+ 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;
+ }
+ state->peer_dane_verified = TRUE;
+
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ /* If a TA-mode TLSA record was used for verification we must additionally
+ verify the CA chain and the cert name. For EE-mode, skip it. */
+
+ if (usage & (1 << DANESSL_USAGE_DANE_EE))
+# endif
+ {
+ state->peer_cert_verified = TRUE;
+ goto goodcert;
+ }
+ }
+#endif
+
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. */
+/* Handle the result of verification. INVALID is set if any others are. */
-if (rc < 0 ||
- verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED)
- )
+if (rc < 0 || verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED))
{
state->peer_cert_verified = FALSE;
if (!*errstr)
*errstr, state->peerdn ? state->peerdn : US"<unset>");
if (state->verify_requirement >= VERIFY_REQUIRED)
- {
- gnutls_alert_send(state->session,
- GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
- return FALSE;
- }
+ goto badcert;
DEBUG(D_tls)
debug_printf("TLS verify failure overridden (host in tls_try_verify_hosts)\n");
}
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;
- }
+ goto badcert;
return TRUE;
}
}
state->peerdn ? state->peerdn : US"<unset>");
}
-state->tlsp->peerdn = state->peerdn;
+goodcert:
+ state->tlsp->peerdn = state->peerdn;
+ return TRUE;
-return TRUE;
+#ifdef SUPPORT_DANE
+tlsa_prob:
+ *errstr = string_sprintf("TLSA record problem: %s", dane_strerror(rc));
+#endif
+
+badcert:
+ gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
+ return FALSE;
}
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)
{
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));
/* Verify after the fact */
-if ( state->verify_requirement != VERIFY_NONE
- && !verify_certificate(state, errstr))
+if (!verify_certificate(state, errstr))
{
if (state->verify_requirement != VERIFY_OPTIONAL)
{
}
+
+
+#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_record * rr;
+dns_scan dnss;
+int i;
+const char ** dane_data;
+int * dane_data_len;
+
+for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS), i = 1;
+ rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
+ ) if (rr->type == T_TLSA) i++;
+
+dane_data = store_get(i * sizeof(uschar *));
+dane_data_len = store_get(i * sizeof(int));
+
+for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS), i = 0;
+ rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
+ ) if (rr->type == T_TLSA)
+ {
+ const uschar * p = rr->data;
+ 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] = 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
+
+
+
/*************************************************
* Start a TLS session in a client *
*************************************************/
host connected host (for messages)
addr the first address (not used)
tb transport (always smtp)
-
+ tlsa_dnsa non-NULL, 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
errstr error string pointer
Returns: OK/DEFER/FAIL (because using common functions),
tls_client_start(int fd, host_item *host,
address_item *addr ARG_UNUSED,
transport_instance * tb,
-#ifdef EXPERIMENTAL_DANE
- dns_answer * tlsa_dnsa ARG_UNUSED,
+#ifdef SUPPORT_DANE
+ dns_answer * tlsa_dnsa,
#endif
uschar ** errstr)
{
smtp_transport_options_block *ob =
(smtp_transport_options_block *)tb->options_block;
int rc;
-exim_gnutls_state_st *state = NULL;
+exim_gnutls_state_st * state = NULL;
#ifndef DISABLE_OCSP
BOOL require_ocsp =
verify_check_given_host(&ob->hosts_require_ocsp, host) == OK;
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 (tlsa_dnsa && dane_tlsa_load(state, 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(&ob->tls_verify_hosts, host) == OK
+ )
{
tls_client_setup_hostname_checks(host, state, ob);
DEBUG(D_tls)
sigalrm_seen = FALSE;
alarm(ob->command_timeout);
do
- {
rc = gnutls_handshake(state->session);
- } while ((rc == GNUTLS_E_AGAIN) ||
- (rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen));
+while (rc == GNUTLS_E_AGAIN || rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen);
alarm(0);
if (rc != GNUTLS_E_SUCCESS)
/* Verify late */
-if (state->verify_requirement != VERIFY_NONE &&
- !verify_certificate(state, errstr))
+if (!verify_certificate(state, errstr))
return tls_error(US"certificate verification failed", *errstr, state->host, errstr);
#ifndef DISABLE_OCSP
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:
+ 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(BOOL is_server, int shutdown)
{
exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
if (shutdown)
{
- DEBUG(D_tls) debug_printf("tls_close(): 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(0);
}
gnutls_deinit(state->session);
state->tlsp->active = -1;
+if (state->xfer_buffer) store_free(state->xfer_buffer);
memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
-if ((state_server.session == NULL) && (state_client.session == NULL))
+if (!state_server.session && !state_client.session)
{
gnutls_global_deinit();
exim_gnutls_base_init_done = FALSE;
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);
inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
MIN(ssl_xfer_buffer_size, lim));
if (sigalrm_seen)
{
DEBUG(D_tls) debug_printf("Got tls read timeout\n");
- state->xfer_error = 1;
+ state->xfer_error = TRUE;
return FALSE;
}
else if (inbytes < 0)
{
record_io_error(state, (int) inbytes, US"recv", NULL);
- state->xfer_error = 1;
+ state->xfer_error = TRUE;
return FALSE;
}
#ifndef DISABLE_DKIM
git://git.exim.org / users / jgh / exim.git / blobdiff