X-Git-Url: https://vcs.fsf.org/?p=exim.git;a=blobdiff_plain;f=src%2Fsrc%2Ftls-gnu.c;h=601197475c71ca424f372f7e236ba3a29529779b;hp=d0e1c35d77af1036112b658096cc25937a9aea08;hb=f4d091fbe1f4cc0a6a7c11c174eaca32402290ec;hpb=65867078f62db450bd8f91100600f6de559e7590 diff --git a/src/src/tls-gnu.c b/src/src/tls-gnu.c index d0e1c35d7..601197475 100644 --- a/src/src/tls-gnu.c +++ b/src/src/tls-gnu.c @@ -2,7 +2,7 @@ * Exim - an Internet mail transport agent * *************************************************/ -/* Copyright (c) University of Cambridge 1995 - 2014 */ +/* Copyright (c) University of Cambridge 1995 - 2015 */ /* See the file NOTICE for conditions of use and distribution. */ /* Copyright (c) Phil Pennock 2012 */ @@ -43,7 +43,24 @@ require current GnuTLS, then we'll drop support for the ancient libraries). #if GNUTLS_VERSION_NUMBER >= 0x020c00 # include #endif -#ifdef EXPERIMENTAL_OCSP +#if GNUTLS_VERSION_NUMBER < 0x030103 && !defined(DISABLE_OCSP) +# warning "GnuTLS library version too old; define DISABLE_OCSP in Makefile" +# define DISABLE_OCSP +#endif +#if GNUTLS_VERSION_NUMBER < 0x020a00 && !defined(DISABLE_EVENT) +# warning "GnuTLS library version too old; tls:cert event unsupported" +# define DISABLE_EVENT +#endif +#if GNUTLS_VERSION_NUMBER >= 0x030306 +# define SUPPORT_CA_DIR +#else +# undef SUPPORT_CA_DIR +#endif +#if GNUTLS_VERSION_NUMBER >= 0x030014 +# define SUPPORT_SYSDEFAULT_CABUNDLE +#endif + +#ifndef DISABLE_OCSP # include #endif @@ -60,7 +77,8 @@ Changes: /* Values for verify_requirement */ -enum peer_verify_requirement { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED }; +enum peer_verify_requirement + { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED }; /* 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 @@ -95,12 +113,17 @@ typedef struct exim_gnutls_state { const uschar *tls_verify_certificates; const uschar *tls_crl; const uschar *tls_require_ciphers; + uschar *exp_tls_certificate; uschar *exp_tls_privatekey; - uschar *exp_tls_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 tls_support *tlsp; /* set in tls_init() */ @@ -115,7 +138,11 @@ 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, NULL, NULL, NULL, NULL, NULL, + NULL, +#ifndef DISABLE_EVENT + NULL, +#endif NULL, NULL, 0, 0, 0, 0, }; @@ -127,7 +154,9 @@ context we're currently dealing with" pointer and rely upon being single-threaded to keep from processing data on an inbound TLS connection while talking to another TLS connection for an outbound check. This does mean that there's no way for heart-beats to be responded to, for the duration of the -second connection. */ +second connection. +XXX But see gnutls_session_get_ptr() +*/ static exim_gnutls_state_st state_server, state_client; @@ -147,6 +176,10 @@ static const char * const exim_default_gnutls_priority = "NORMAL"; static BOOL exim_gnutls_base_init_done = FALSE; +#ifndef DISABLE_OCSP +static BOOL gnutls_buggy_ocsp = FALSE; +#endif + /* ------------------------------------------------------------------------ */ /* macros */ @@ -157,18 +190,18 @@ static BOOL exim_gnutls_base_init_done = FALSE; the library logging; a value less than 0 disables the calls to set up logging callbacks. */ #ifndef EXIM_GNUTLS_LIBRARY_LOG_LEVEL -#define EXIM_GNUTLS_LIBRARY_LOG_LEVEL -1 +# define EXIM_GNUTLS_LIBRARY_LOG_LEVEL -1 #endif #ifndef EXIM_CLIENT_DH_MIN_BITS -#define EXIM_CLIENT_DH_MIN_BITS 1024 +# define EXIM_CLIENT_DH_MIN_BITS 1024 #endif /* With GnuTLS 2.12.x+ we have gnutls_sec_param_to_pk_bits() with which we can ask for a bit-strength. Without that, we stick to the constant we had before, for now. */ #ifndef EXIM_SERVER_DH_BITS_PRE2_12 -#define EXIM_SERVER_DH_BITS_PRE2_12 1024 +# define EXIM_SERVER_DH_BITS_PRE2_12 1024 #endif #define exim_gnutls_err_check(Label) do { \ @@ -177,18 +210,18 @@ before, for now. */ #define expand_check_tlsvar(Varname) expand_check(state->Varname, US #Varname, &state->exp_##Varname) #if GNUTLS_VERSION_NUMBER >= 0x020c00 -#define HAVE_GNUTLS_SESSION_CHANNEL_BINDING -#define HAVE_GNUTLS_SEC_PARAM_CONSTANTS -#define HAVE_GNUTLS_RND +# define HAVE_GNUTLS_SESSION_CHANNEL_BINDING +# define HAVE_GNUTLS_SEC_PARAM_CONSTANTS +# define HAVE_GNUTLS_RND /* The security fix we provide with the gnutls_allow_auto_pkcs11 option * (4.82 PP/09) introduces a compatibility regression. The symbol simply * isn't available sometimes, so this needs to become a conditional * compilation; the sanest way to deal with this being a problem on * older OSes is to block it in the Local/Makefile with this compiler * definition */ -#ifndef AVOID_GNUTLS_PKCS11 -#define HAVE_GNUTLS_PKCS11 -#endif /* AVOID_GNUTLS_PKCS11 */ +# ifndef AVOID_GNUTLS_PKCS11 +# define HAVE_GNUTLS_PKCS11 +# endif /* AVOID_GNUTLS_PKCS11 */ #endif @@ -203,6 +236,10 @@ static void exim_gnutls_logger_cb(int level, const char *message); 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); +#endif @@ -235,7 +272,7 @@ tls_error(const uschar *prefix, const char *msg, const host_item *host) { if (host) { - log_write(0, LOG_MAIN, "TLS error on connection to %s [%s] (%s)%s%s", + 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; } @@ -244,6 +281,7 @@ 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; @@ -289,13 +327,19 @@ tls_error(when, msg, state->host); * Set various Exim expansion vars * *************************************************/ -#define exim_gnutls_cert_err(Label) do { \ - if (rc != GNUTLS_E_SUCCESS) { \ - DEBUG(D_tls) debug_printf("TLS: cert problem: %s: %s\n", (Label), gnutls_strerror(rc)); \ - return rc; } } while (0) +#define exim_gnutls_cert_err(Label) \ + do \ + { \ + if (rc != GNUTLS_E_SUCCESS) \ + { \ + DEBUG(D_tls) debug_printf("TLS: cert problem: %s: %s\n", \ + (Label), gnutls_strerror(rc)); \ + return rc; \ + } \ + } while (0) static int -import_cert(const gnutls_datum * cert, gnutls_x509_crt_t * crtp) +import_cert(const gnutls_datum_t * cert, gnutls_x509_crt_t * crtp) { int rc; @@ -369,7 +413,7 @@ if (rc) { } else { old_pool = store_pool; store_pool = POOL_PERM; - tls_channelbinding_b64 = auth_b64encode(channel.data, (int)channel.size); + tls_channelbinding_b64 = b64encode(channel.data, (int)channel.size); store_pool = old_pool; DEBUG(D_tls) debug_printf("Have channel bindings cached for possible auth usage.\n"); } @@ -381,7 +425,7 @@ tlsp->sni = state->received_sni; /* record our certificate */ { - const gnutls_datum * cert = gnutls_certificate_get_ours(state->session); + const gnutls_datum_t * cert = gnutls_certificate_get_ours(state->session); gnutls_x509_crt_t crt; tlsp->ourcert = cert && import_cert(cert, &crt)==0 ? crt : NULL; @@ -413,7 +457,7 @@ init_server_dh(void) { int fd, rc; unsigned int dh_bits; -gnutls_datum m; +gnutls_datum_t m; uschar filename_buf[PATH_MAX]; uschar *filename = NULL; size_t sz; @@ -786,23 +830,30 @@ if (state->exp_tls_certificate && *state->exp_tls_certificate) /* Set the OCSP stapling server info */ -#ifdef EXPERIMENTAL_OCSP +#ifndef DISABLE_OCSP if ( !host /* server */ && tls_ocsp_file ) { - uschar * expanded; - int rc; + if (gnutls_buggy_ocsp) + { + DEBUG(D_tls) debug_printf("GnuTLS library is buggy for OCSP; avoiding\n"); + } + else + { + if (!expand_check(tls_ocsp_file, US"tls_ocsp_file", + &state->exp_tls_ocsp_file)) + return DEFER; - if (!expand_check(tls_ocsp_file, US"tls_ocsp_file", &expanded)) - 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. */ - /* Lazy way; would like callback to emit debug on actual response */ + gnutls_certificate_set_ocsp_status_request_function(state->x509_cred, + server_ocsp_stapling_cb, state->exp_tls_ocsp_file); - rc = gnutls_certificate_set_ocsp_status_request_file(state->x509_cred, - expanded, 0); - exim_gnutls_err_check(US"gnutls_certificate_set_ocsp_status_request_file"); - DEBUG(D_tls) debug_printf("Set OCSP response file %s\n", expanded); + DEBUG(D_tls) debug_printf("OCSP response file = %s\n", state->exp_tls_ocsp_file); + } } #endif @@ -817,6 +868,10 @@ if (state->tls_verify_certificates && *state->tls_verify_certificates) { if (!expand_check_tlsvar(tls_verify_certificates)) 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)) return DEFER; @@ -837,46 +892,65 @@ else return OK; } -if (Ustat(state->exp_tls_verify_certificates, &statbuf) < 0) +#ifdef SUPPORT_SYSDEFAULT_CABUNDLE +if (Ustrcmp(state->exp_tls_verify_certificates, "system") == 0) + cert_count = gnutls_certificate_set_x509_system_trust(state->x509_cred); +else +#endif { - log_write(0, LOG_MAIN|LOG_PANIC, "could not stat %s " - "(tls_verify_certificates): %s", state->exp_tls_verify_certificates, - strerror(errno)); - return DEFER; - } + if (Ustat(state->exp_tls_verify_certificates, &statbuf) < 0) + { + log_write(0, LOG_MAIN|LOG_PANIC, "could not stat %s " + "(tls_verify_certificates): %s", state->exp_tls_verify_certificates, + strerror(errno)); + return DEFER; + } -/* The test suite passes in /dev/null; we could check for that path explicitly, -but who knows if someone has some weird FIFO which always dumps some certs, or -other weirdness. The thing we really want to check is that it's not a -directory, since while OpenSSL supports that, GnuTLS does not. -So s/!S_ISREG/S_ISDIR/ and change some messsaging ... */ -if (S_ISDIR(statbuf.st_mode)) - { - DEBUG(D_tls) - debug_printf("verify certificates path is a dir: \"%s\"\n", - state->exp_tls_verify_certificates); - log_write(0, LOG_MAIN|LOG_PANIC, - "tls_verify_certificates \"%s\" is a directory", - state->exp_tls_verify_certificates); - return DEFER; - } +#ifndef SUPPORT_CA_DIR + /* The test suite passes in /dev/null; we could check for that path explicitly, + but who knows if someone has some weird FIFO which always dumps some certs, or + other weirdness. The thing we really want to check is that it's not a + directory, since while OpenSSL supports that, GnuTLS does not. + So s/!S_ISREG/S_ISDIR/ and change some messsaging ... */ + if (S_ISDIR(statbuf.st_mode)) + { + DEBUG(D_tls) + debug_printf("verify certificates path is a dir: \"%s\"\n", + state->exp_tls_verify_certificates); + log_write(0, LOG_MAIN|LOG_PANIC, + "tls_verify_certificates \"%s\" is a directory", + state->exp_tls_verify_certificates); + return DEFER; + } +#endif -DEBUG(D_tls) debug_printf("verify certificates = %s size=" OFF_T_FMT "\n", - state->exp_tls_verify_certificates, statbuf.st_size); + DEBUG(D_tls) debug_printf("verify certificates = %s size=" OFF_T_FMT "\n", + state->exp_tls_verify_certificates, statbuf.st_size); -if (statbuf.st_size == 0) - { - DEBUG(D_tls) - debug_printf("cert file empty, no certs, no verification, ignoring any CRL\n"); - return OK; + if (statbuf.st_size == 0) + { + DEBUG(D_tls) + debug_printf("cert file empty, no certs, no verification, ignoring any CRL\n"); + return OK; + } + + cert_count = + +#ifdef SUPPORT_CA_DIR + (statbuf.st_mode & S_IFMT) == S_IFDIR + ? + gnutls_certificate_set_x509_trust_dir(state->x509_cred, + CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM) + : +#endif + gnutls_certificate_set_x509_trust_file(state->x509_cred, + CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM); } -cert_count = gnutls_certificate_set_x509_trust_file(state->x509_cred, - CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM); if (cert_count < 0) { rc = cert_count; - exim_gnutls_err_check(US"gnutls_certificate_set_x509_trust_file"); + exim_gnutls_err_check(US"setting certificate trust"); } DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", cert_count); @@ -948,6 +1022,38 @@ return OK; * Initialize for GnuTLS * *************************************************/ + +#ifndef DISABLE_OCSP + +static BOOL +tls_is_buggy_ocsp(void) +{ +const uschar * s; +uschar maj, mid, mic; + +s = CUS gnutls_check_version(NULL); +maj = atoi(CCS s); +if (maj == 3) + { + while (*s && *s != '.') s++; + mid = atoi(CCS ++s); + if (mid <= 2) + return TRUE; + else if (mid >= 5) + return FALSE; + else + { + while (*s && *s != '.') s++; + mic = atoi(CCS ++s); + return mic <= (mid == 3 ? 16 : 3); + } + } +return FALSE; +} + +#endif + + /* Called from both server and client code. In the case of a server, errors before actual TLS negotiation return DEFER. @@ -1011,6 +1117,11 @@ if (!exim_gnutls_base_init_done) } #endif +#ifndef DISABLE_OCSP + if (tls_ocsp_file && (gnutls_buggy_ocsp = tls_is_buggy_ocsp())) + log_write(0, LOG_MAIN, "OCSP unusable with this GnuTLS library version"); +#endif + exim_gnutls_base_init_done = TRUE; } @@ -1058,15 +1169,15 @@ if (rc != OK) return rc; /* set SNI in client, only */ if (host) { - if (!expand_check(state->tlsp->sni, US"tls_out_sni", &state->exp_tls_sni)) + if (!expand_check(sni, US"tls_out_sni", &state->tlsp->sni)) return DEFER; - if (state->exp_tls_sni && *state->exp_tls_sni) + if (state->tlsp->sni && *state->tlsp->sni) { DEBUG(D_tls) - debug_printf("Setting TLS client SNI to \"%s\"\n", state->exp_tls_sni); - sz = Ustrlen(state->exp_tls_sni); + 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->exp_tls_sni, sz); + GNUTLS_NAME_DNS, state->tlsp->sni, sz); exim_gnutls_err_check(US"gnutls_server_name_set"); } } @@ -1166,7 +1277,7 @@ static int peer_status(exim_gnutls_state_st *state) { uschar cipherbuf[256]; -const gnutls_datum *cert_list; +const gnutls_datum_t *cert_list; int old_pool, rc; unsigned int cert_list_size = 0; gnutls_protocol_t protocol; @@ -1215,7 +1326,7 @@ if (cert_list == NULL || 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) + if (state->verify_requirement >= VERIFY_REQUIRED) return tls_error(US"certificate verification failed", "no certificate received from peer", state->host); return OK; @@ -1227,17 +1338,23 @@ if (ct != GNUTLS_CRT_X509) const char *ctn = 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) + if (state->verify_requirement >= VERIFY_REQUIRED) return tls_error(US"certificate verification not possible, unhandled type", ctn, state->host); return OK; } -#define exim_gnutls_peer_err(Label) do { \ - if (rc != GNUTLS_E_SUCCESS) { \ - 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 OK; } } while (0) +#define exim_gnutls_peer_err(Label) \ + do { \ + if (rc != GNUTLS_E_SUCCESS) \ + { \ + 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 OK; \ + } \ + } while (0) rc = import_cert(&cert_list[0], &crt); exim_gnutls_peer_err(US"cert 0"); @@ -1301,7 +1418,9 @@ else /* 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)) +if (rc < 0 || + verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED) + ) { state->peer_cert_verified = FALSE; if (!*error) @@ -1309,21 +1428,44 @@ if (rc < 0 || verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED)) ? "certificate revoked" : "certificate invalid"; DEBUG(D_tls) - debug_printf("TLS certificate verification failed (%s): peerdn=%s\n", + debug_printf("TLS certificate verification failed (%s): peerdn=\"%s\"\n", *error, state->peerdn ? state->peerdn : US""); - if (state->verify_requirement == VERIFY_REQUIRED) + if (state->verify_requirement >= VERIFY_REQUIRED) { - gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE); + 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"); } + 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) + { + 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; + } + } state->peer_cert_verified = TRUE; - DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=%s\n", + DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=\"%s\"\n", state->peerdn ? state->peerdn : US""); } @@ -1433,6 +1575,79 @@ 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 +for an exim TLS connection (either direction), raising a tls:cert event +for each cert in the chain presented by the peer. Any event +can deny verification. + +Return 0 for the handshake to continue or non-zero to terminate. +*/ + +static int +verify_cb(gnutls_session_t session) +{ +const gnutls_datum_t * cert_list; +unsigned int cert_list_size = 0; +gnutls_x509_crt_t crt; +int rc; +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) + while (cert_list_size--) + { + rc = import_cert(&cert_list[cert_list_size], &crt); + if (rc != GNUTLS_E_SUCCESS) + { + DEBUG(D_tls) debug_printf("TLS: peer cert problem: depth %d: %s\n", + cert_list_size, gnutls_strerror(rc)); + break; + } + + state->tlsp->peercert = crt; + if ((yield = event_raise(state->event_action, + US"tls:cert", string_sprintf("%d", cert_list_size)))) + { + log_write(0, LOG_MAIN, + "SSL verify denied by event-action: depth=%d: %s", + cert_list_size, yield); + return 1; /* reject */ + } + state->tlsp->peercert = NULL; + } + +return 0; +} + +#endif + + /* ------------------------------------------------------------------------ */ /* Exported functions */ @@ -1487,23 +1702,35 @@ optional, set up appropriately. */ if (verify_check_host(&tls_verify_hosts) == OK) { - DEBUG(D_tls) debug_printf("TLS: a client certificate will be required.\n"); + DEBUG(D_tls) + debug_printf("TLS: a client certificate will be required.\n"); state->verify_requirement = VERIFY_REQUIRED; gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE); } else if (verify_check_host(&tls_try_verify_hosts) == OK) { - DEBUG(D_tls) debug_printf("TLS: a client certificate will be requested but not required.\n"); + DEBUG(D_tls) + debug_printf("TLS: a client certificate will be requested but not required.\n"); state->verify_requirement = VERIFY_OPTIONAL; gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUEST); } else { - DEBUG(D_tls) debug_printf("TLS: a client certificate will not be requested.\n"); + DEBUG(D_tls) + debug_printf("TLS: a client certificate will not be requested.\n"); state->verify_requirement = VERIFY_NONE; gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_IGNORE); } +#ifndef DISABLE_EVENT +if (event_action) + { + state->event_action = event_action; + gnutls_session_set_ptr(state->session, state); + gnutls_certificate_set_verify_function(state->x509_cred, verify_cb); + } +#endif + /* Register SNI handling; always, even if not in tls_certificate, so that the expansion variable $tls_sni is always available. */ @@ -1526,8 +1753,8 @@ if (!state->tlsp->on_connect) that the GnuTLS library doesn't. */ gnutls_transport_set_ptr2(state->session, - (gnutls_transport_ptr)fileno(smtp_in), - (gnutls_transport_ptr)fileno(smtp_out)); + (gnutls_transport_ptr_t)(long) fileno(smtp_in), + (gnutls_transport_ptr_t)(long) fileno(smtp_out)); state->fd_in = fileno(smtp_in); state->fd_out = fileno(smtp_out); @@ -1600,6 +1827,25 @@ return OK; +static void +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) + { + state->exp_tls_verify_cert_hostnames = +#ifdef SUPPORT_I18N + string_domain_utf8_to_alabel(host->name, NULL); +#else + host->name; +#endif + DEBUG(D_tls) + debug_printf("TLS: server cert verification includes hostname: \"%s\".\n", + state->exp_tls_verify_cert_hostnames); + } +} + + /************************************************* * Start a TLS session in a client * *************************************************/ @@ -1610,7 +1856,7 @@ Arguments: fd the fd of the connection host connected host (for messages) addr the first address (not used) - ob smtp transport options + tb transport (always smtp) Returns: OK/DEFER/FAIL (because using common functions), but for a client, DEFER and FAIL have the same meaning @@ -1619,15 +1865,22 @@ Returns: OK/DEFER/FAIL (because using common functions), int tls_client_start(int fd, host_item *host, address_item *addr ARG_UNUSED, - void *v_ob) + transport_instance *tb +#ifdef EXPERIMENTAL_DANE + , dne_answer * unused_tlsa_dnsa +#endif + ) { -smtp_transport_options_block *ob = v_ob; +smtp_transport_options_block *ob = + (smtp_transport_options_block *)tb->options_block; int rc; const char *error; exim_gnutls_state_st *state = NULL; -#ifdef EXPERIMENTAL_OCSP -BOOL require_ocsp = verify_check_this_host(&ob->hosts_require_ocsp, - NULL, host->name, host->address, NULL) == OK; +#ifndef DISABLE_OCSP +BOOL require_ocsp = + verify_check_given_host(&ob->hosts_require_ocsp, host) == OK; +BOOL request_ocsp = require_ocsp ? TRUE + : verify_check_given_host(&ob->hosts_request_ocsp, host) == OK; #endif DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", fd); @@ -1654,47 +1907,62 @@ if ((rc = tls_init(host, ob->tls_certificate, ob->tls_privatekey, gnutls_dh_set_prime_bits(state->session, dh_min_bits); } -/* Stick to the old behaviour for compatibility if tls_verify_certificates is +/* Stick to the old behaviour for compatibility if tls_verify_certificates is 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 - ) - || - verify_check_host(&ob->tls_verify_hosts) == OK +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 ) { - DEBUG(D_tls) debug_printf("TLS: server certificate verification required.\n"); + tls_client_setup_hostname_checks(host, state, ob); + DEBUG(D_tls) + debug_printf("TLS: server certificate verification required.\n"); state->verify_requirement = VERIFY_REQUIRED; gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE); } -else if (verify_check_host(&ob->tls_try_verify_hosts) == OK) +else if (verify_check_given_host(&ob->tls_try_verify_hosts, host) == OK) { - DEBUG(D_tls) debug_printf("TLS: server certificate verification optional.\n"); + tls_client_setup_hostname_checks(host, state, ob); + DEBUG(D_tls) + debug_printf("TLS: server certificate verification optional.\n"); state->verify_requirement = VERIFY_OPTIONAL; gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUEST); } else { - DEBUG(D_tls) debug_printf("TLS: server certificate verification not required.\n"); + DEBUG(D_tls) + debug_printf("TLS: server certificate verification not required.\n"); state->verify_requirement = VERIFY_NONE; gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_IGNORE); } -#ifdef EXPERIMENTAL_OCSP /* since GnuTLS 3.1.3 */ -if (require_ocsp) +#ifndef DISABLE_OCSP + /* supported since GnuTLS 3.1.3 */ +if (request_ocsp) { 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; + } +#endif + +#ifndef DISABLE_EVENT +if (tb->event_action) + { + state->event_action = tb->event_action; + gnutls_session_set_ptr(state->session, state); + gnutls_certificate_set_verify_function(state->x509_cred, verify_cb); } #endif -gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr)fd); +gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr_t)(long) fd); state->fd_in = fd; state->fd_out = fd; @@ -1722,7 +1990,7 @@ if (state->verify_requirement != VERIFY_NONE && !verify_certificate(state, &error)) return tls_error(US"certificate verification failed", error, state->host); -#ifdef EXPERIMENTAL_OCSP +#ifndef DISABLE_OCSP if (require_ocsp) { DEBUG(D_tls) @@ -1744,8 +2012,12 @@ if (require_ocsp) } 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); + } DEBUG(D_tls) debug_printf("Passed OCSP checking\n"); + tls_out.ocsp = OCSP_VFIED; } #endif