X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/038597d295fa0ebd48ed4c00a6dfff0f30a2353a..0cbf2b821bb13da0268556d0e30ea627d5592c60:/src/src/tls-openssl.c diff --git a/src/src/tls-openssl.c b/src/src/tls-openssl.c index f183e8b45..3430e4eac 100644 --- a/src/src/tls-openssl.c +++ b/src/src/tls-openssl.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. */ /* Portions Copyright (c) The OpenSSL Project 1999 */ @@ -22,6 +22,9 @@ functions from the OpenSSL library. */ #include #include #include +#ifndef OPENSSL_NO_ECDH +# include +#endif #ifndef DISABLE_OCSP # include #endif @@ -38,12 +41,37 @@ functions from the OpenSSL library. */ #if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT) # define EXIM_HAVE_OPENSSL_TLSEXT #endif -#if OPENSSL_VERSION_NUMBER >= 0x010100000L -# define EXIM_HAVE_OPENSSL_CHECKHOST -#endif -#if OPENSSL_VERSION_NUMBER >= 0x010000000L \ + +/* + * X509_check_host provides sane certificate hostname checking, but was added + * to OpenSSL late, after other projects forked off the code-base. So in + * addition to guarding against the base version number, beware that LibreSSL + * does not (at this time) support this function. + * + * If LibreSSL gains a different API, perhaps via libtls, then we'll probably + * opt to disentangle and ask a LibreSSL user to provide glue for a third + * crypto provider for libtls instead of continuing to tie the OpenSSL glue + * into even twistier knots. If LibreSSL gains the same API, we can just + * change this guard and punt the issue for a while longer. + */ +#ifndef LIBRESSL_VERSION_NUMBER +# if OPENSSL_VERSION_NUMBER >= 0x010100000L +# define EXIM_HAVE_OPENSSL_CHECKHOST +# endif +# if OPENSSL_VERSION_NUMBER >= 0x010000000L \ && (OPENSSL_VERSION_NUMBER & 0x0000ff000L) >= 0x000002000L -# define EXIM_HAVE_OPENSSL_CHECKHOST +# define EXIM_HAVE_OPENSSL_CHECKHOST +# endif + +# if !defined(OPENSSL_NO_ECDH) +# if OPENSSL_VERSION_NUMBER >= 0x0090800fL +# define EXIM_HAVE_ECDH +# endif +# if OPENSSL_VERSION_NUMBER >= 0x10002000L +# define EXIM_HAVE_OPENSSL_ECDH_AUTO +# define EXIM_HAVE_OPENSSL_EC_NIST2NID +# endif +# endif #endif #if !defined(EXIM_HAVE_OPENSSL_TLSEXT) && !defined(DISABLE_OCSP) @@ -124,7 +152,7 @@ typedef struct tls_ext_ctx_cb { /* only passed down to tls_error: */ host_item *host; const uschar * verify_cert_hostnames; -#ifdef EXPERIMENTAL_EVENT +#ifndef DISABLE_EVENT uschar * event_action; #endif } tls_ext_ctx_cb; @@ -254,7 +282,7 @@ for(i= 0; iu_ocsp.client.verify_store, cert)) ERR_clear_error(); } #endif -#ifdef EXPERIMENTAL_EVENT +#ifndef DISABLE_EVENT if (verify_event(tlsp, cert, depth, dn, calledp, optionalp, US"SSL")) return 0; /* reject, with peercert set */ #endif @@ -426,7 +454,7 @@ else } } -#ifdef EXPERIMENTAL_EVENT +#ifndef DISABLE_EVENT if (verify_event(tlsp, cert, depth, dn, calledp, optionalp, US"SSL")) return 0; /* reject, with peercert set */ #endif @@ -463,7 +491,7 @@ verify_callback_client_dane(int state, X509_STORE_CTX * x509ctx) { X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx); uschar dn[256]; -#ifdef EXPERIMENTAL_EVENT +#ifndef DISABLE_EVENT int depth = X509_STORE_CTX_get_error_depth(x509ctx); BOOL dummy_called, optional = FALSE; #endif @@ -473,7 +501,7 @@ dn[sizeof(dn)-1] = '\0'; DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s\n", dn); -#ifdef EXPERIMENTAL_EVENT +#ifndef DISABLE_EVENT if (verify_event(&tls_out, cert, depth, dn, &dummy_called, &optional, US"DANE")) return 0; /* reject, with peercert set */ @@ -629,42 +657,74 @@ Returns: TRUE if OK (nothing to set up, or setup worked) */ static BOOL -init_ecdh(SSL_CTX *sctx, host_item *host) +init_ecdh(SSL_CTX * sctx, host_item * host) { +#ifdef OPENSSL_NO_ECDH +return TRUE; +#else + +EC_KEY * ecdh; +uschar * exp_curve; +int nid; +BOOL rv; + if (host) /* No ECDH setup for clients, only for servers */ return TRUE; -#ifndef SSL_CTX_set_tmp_ecdh -/* No elliptic curve API in OpenSSL, skip it */ +# ifndef EXIM_HAVE_ECDH DEBUG(D_tls) debug_printf("No OpenSSL API to define ECDH parameters, skipping\n"); return TRUE; -#else -# ifndef NID_X9_62_prime256v1 -/* For now, stick to NIST P-256 to get "something" running. -If that's not available, bail */ -DEBUG(D_tls) - debug_printf("NIST P-256 EC curve not available, skipping ECDH setup\n"); -return TRUE; # else + +if (!expand_check(tls_eccurve, US"tls_eccurve", &exp_curve)) + return FALSE; +if (!exp_curve || !*exp_curve) + return TRUE; + +# ifdef EXIM_HAVE_OPENSSL_ECDH_AUTO +/* check if new enough library to support auto ECDH temp key parameter selection */ +if (Ustrcmp(exp_curve, "auto") == 0) { - EC_KEY * ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1); - BOOL rv; + DEBUG(D_tls) debug_printf( + "ECDH temp key parameter settings: OpenSSL 1.2+ autoselection\n"); + SSL_CTX_set_ecdh_auto(sctx, 1); + return TRUE; + } +# endif - /* The "tmp" in the name here refers to setting a tempoary key - not to the stability of the interface. */ +DEBUG(D_tls) debug_printf("ECDH: curve '%s'\n", exp_curve); +if ( (nid = OBJ_sn2nid (CCS exp_curve)) == NID_undef +# ifdef EXIM_HAVE_OPENSSL_EC_NIST2NID + && (nid = EC_curve_nist2nid(CCS exp_curve)) == NID_undef +# endif + ) + { + tls_error(string_sprintf("Unknown curve name tls_eccurve '%s'", + exp_curve), + host, NULL); + return FALSE; + } - if ((rv = SSL_CTX_set_tmp_ecdh(sctx, ecdh) != 0)) - { - DEBUG(D_tls) debug_printf("ECDH: enable NIST P-256 curve\n"); - } - else - tls_error(US"Error enabling NIST P-256 curve", host, NULL); - EC_KEY_free(ecdh); - return rv; +if (!(ecdh = EC_KEY_new_by_curve_name(nid))) + { + tls_error(US"Unable to create ec curve", host, NULL); + return FALSE; } -# endif -#endif + +/* The "tmp" in the name here refers to setting a temporary key +not to the stability of the interface. */ + +if ((rv = SSL_CTX_set_tmp_ecdh(sctx, ecdh) == 0)) + tls_error(string_sprintf("Error enabling '%s' curve", exp_curve), host, NULL); +else + DEBUG(D_tls) debug_printf("ECDH: enabled '%s' curve\n", exp_curve); + +EC_KEY_free(ecdh); +return !rv; + +# endif /*EXIM_HAVE_ECDH*/ +#endif /*OPENSSL_NO_ECDH*/ } @@ -1009,7 +1069,7 @@ uschar *response_der; int response_der_len; DEBUG(D_tls) - debug_printf("Received TLS status request (OCSP stapling); %s response.", + debug_printf("Received TLS status request (OCSP stapling); %s response\n", cbinfo->u_ocsp.server.response ? "have" : "lack"); tls_in.ocsp = OCSP_NOT_RESP; @@ -1051,8 +1111,7 @@ len = SSL_get_tlsext_status_ocsp_resp(s, &p); if(!p) { /* Expect this when we requested ocsp but got none */ - if ( cbinfo->u_ocsp.client.verify_required - && log_extra_selector & LX_tls_cipher) + if (cbinfo->u_ocsp.client.verify_required && LOGGING(tls_cipher)) log_write(0, LOG_MAIN, "Received TLS status callback, null content"); else DEBUG(D_tls) debug_printf(" null\n"); @@ -1062,7 +1121,7 @@ if(!p) if(!(rsp = d2i_OCSP_RESPONSE(NULL, &p, len))) { tls_out.ocsp = OCSP_FAILED; - if (log_extra_selector & LX_tls_cipher) + if (LOGGING(tls_cipher)) log_write(0, LOG_MAIN, "Received TLS cert status response, parse error"); else DEBUG(D_tls) debug_printf(" parse error\n"); @@ -1072,7 +1131,7 @@ if(!(rsp = d2i_OCSP_RESPONSE(NULL, &p, len))) if(!(bs = OCSP_response_get1_basic(rsp))) { tls_out.ocsp = OCSP_FAILED; - if (log_extra_selector & LX_tls_cipher) + if (LOGGING(tls_cipher)) log_write(0, LOG_MAIN, "Received TLS cert status response, error parsing response"); else DEBUG(D_tls) debug_printf(" error parsing response\n"); @@ -1103,7 +1162,7 @@ if(!(bs = OCSP_response_get1_basic(rsp))) cbinfo->u_ocsp.client.verify_store, 0)) <= 0) { tls_out.ocsp = OCSP_FAILED; - if (log_extra_selector & LX_tls_cipher) + if (LOGGING(tls_cipher)) log_write(0, LOG_MAIN, "Received TLS cert status response, itself unverifiable"); BIO_printf(bp, "OCSP response verify failure\n"); ERR_print_errors(bp); @@ -1225,7 +1284,7 @@ else cbinfo->dhparam = dhparam; cbinfo->server_cipher_list = NULL; cbinfo->host = host; -#ifdef EXPERIMENTAL_EVENT +#ifndef DISABLE_EVENT cbinfo->event_action = NULL; #endif @@ -1306,6 +1365,7 @@ else DEBUG(D_tls) debug_printf("no SSL CTX options to set\n"); /* Initialize with DH parameters if supplied */ +/* Initialize ECDH temp key parameter selection */ if ( !init_dh(*ctxp, dhparam, host) || !init_ecdh(*ctxp, host) @@ -1778,7 +1838,7 @@ tls_client_basic_ctx_init(SSL_CTX * ctx, ) { int rc; -/* 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 is not set. Check only the specified host patterns if one of them is defined */ @@ -1800,7 +1860,7 @@ if ((rc = setup_certs(ctx, ob->tls_verify_certificates, if (verify_check_given_host(&ob->tls_verify_cert_hostnames, host) == OK) { cbinfo->verify_cert_hostnames = -#ifdef EXPERIMENTAL_INTERNATIONAL +#ifdef SUPPORT_I18N string_domain_utf8_to_alabel(host->name, NULL); #else host->name; @@ -2052,7 +2112,7 @@ if (request_ocsp) } #endif -#ifdef EXPERIMENTAL_EVENT +#ifndef DISABLE_EVENT client_static_cbinfo->event_action = tb->event_action; #endif