X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=ssl%2Fstatem%2Fextensions.c;h=96c5394bd67a90999fe1117e44afbefd3f2d5830;hb=9784ec04745a8c8ecbf5610c0a2f5540e1e0f2cd;hp=c9e7d30eaae150454dbe15a77938e91b20551ba9;hpb=0247086d9a0713e18a0f16949039a40fdb63ff7e;p=oweals%2Fopenssl.git diff --git a/ssl/statem/extensions.c b/ssl/statem/extensions.c index c9e7d30eaa..96c5394bd6 100644 --- a/ssl/statem/extensions.c +++ b/ssl/statem/extensions.c @@ -7,6 +7,7 @@ * https://www.openssl.org/source/license.html */ +#include #include "../ssl_locl.h" #include "statem_locl.h" @@ -29,6 +30,13 @@ static int init_npn(SSL *s, unsigned int context); static int init_alpn(SSL *s, unsigned int context); static int final_alpn(SSL *s, unsigned int context, int sent, int *al); static int init_sig_algs(SSL *s, unsigned int context); +static int init_certificate_authorities(SSL *s, unsigned int context); +static int tls_construct_certificate_authorities(SSL *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx, int *al); +static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx, int *al); #ifndef OPENSSL_NO_SRP static int init_srp(SSL *s, unsigned int context); #endif @@ -36,11 +44,14 @@ static int init_etm(SSL *s, unsigned int context); static int init_ems(SSL *s, unsigned int context); static int final_ems(SSL *s, unsigned int context, int sent, int *al); static int init_psk_kex_modes(SSL *s, unsigned int context); +#ifndef OPENSSL_NO_EC static int final_key_share(SSL *s, unsigned int context, int sent, int *al); +#endif #ifndef OPENSSL_NO_SRTP static int init_srtp(SSL *s, unsigned int context); #endif static int final_sig_algs(SSL *s, unsigned int context, int sent, int *al); +static int final_early_data(SSL *s, unsigned int context, int sent, int *al); /* Structure to define a built-in extension */ typedef struct extensions_definition_st { @@ -57,15 +68,17 @@ typedef struct extensions_definition_st { */ int (*init)(SSL *s, unsigned int context); /* Parse extension sent from client to server */ - int (*parse_ctos)(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al); + int (*parse_ctos)(SSL *s, PACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al); /* Parse extension send from server to client */ - int (*parse_stoc)(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al); + int (*parse_stoc)(SSL *s, PACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al); /* Construct extension sent from server to client */ - int (*construct_stoc)(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, - int *al); + int (*construct_stoc)(SSL *s, WPACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al); /* Construct extension sent from client to server */ - int (*construct_ctos)(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, - int *al); + int (*construct_ctos)(SSL *s, WPACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al); /* * Finalise extension after parsing. Always called where an extensions was * initialised even if the extension was not present. |sent| is set to 1 if @@ -153,8 +166,9 @@ static const EXTENSION_DEFINITION ext_defs[] = { }, { TLSEXT_TYPE_signature_algorithms, - EXT_CLIENT_HELLO, - init_sig_algs, tls_parse_ctos_sig_algs, NULL, NULL, + EXT_CLIENT_HELLO | EXT_TLS1_3_CERTIFICATE_REQUEST, + init_sig_algs, tls_parse_ctos_sig_algs, + tls_parse_ctos_sig_algs, tls_construct_ctos_sig_algs, tls_construct_ctos_sig_algs, final_sig_algs }, #ifndef OPENSSL_NO_OCSP @@ -203,7 +217,7 @@ static const EXTENSION_DEFINITION ext_defs[] = { #endif { TLSEXT_TYPE_encrypt_then_mac, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY, + EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY | EXT_SSL3_ALLOWED, init_etm, tls_parse_ctos_etm, tls_parse_stoc_etm, tls_construct_stoc_etm, tls_construct_ctos_etm, NULL }, @@ -237,12 +251,12 @@ static const EXTENSION_DEFINITION ext_defs[] = { NULL, NULL, NULL, tls_construct_ctos_supported_versions, NULL }, { - /* Must be before key_share */ TLSEXT_TYPE_psk_kex_modes, EXT_CLIENT_HELLO | EXT_TLS_IMPLEMENTATION_ONLY | EXT_TLS1_3_ONLY, init_psk_kex_modes, tls_parse_ctos_psk_kex_modes, NULL, NULL, tls_construct_ctos_psk_kex_modes, NULL }, +#ifndef OPENSSL_NO_EC { /* * Must be in this list after supported_groups. We need that to have @@ -256,6 +270,14 @@ static const EXTENSION_DEFINITION ext_defs[] = { tls_construct_stoc_key_share, tls_construct_ctos_key_share, final_key_share }, +#endif + { + TLSEXT_TYPE_cookie, + EXT_CLIENT_HELLO | EXT_TLS1_3_HELLO_RETRY_REQUEST + | EXT_TLS_IMPLEMENTATION_ONLY | EXT_TLS1_3_ONLY, + NULL, NULL, tls_parse_stoc_cookie, NULL, tls_construct_ctos_cookie, + NULL + }, { /* * Special unsolicited ServerHello extension only used when @@ -265,9 +287,24 @@ static const EXTENSION_DEFINITION ext_defs[] = { EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY, NULL, NULL, NULL, tls_construct_stoc_cryptopro_bug, NULL, NULL }, + { + TLSEXT_TYPE_early_data, + EXT_CLIENT_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS + | EXT_TLS1_3_NEW_SESSION_TICKET, + NULL, tls_parse_ctos_early_data, tls_parse_stoc_early_data, + tls_construct_stoc_early_data, tls_construct_ctos_early_data, + final_early_data + }, + { + TLSEXT_TYPE_certificate_authorities, + EXT_CLIENT_HELLO | EXT_TLS1_3_CERTIFICATE_REQUEST | EXT_TLS1_3_ONLY, + init_certificate_authorities, + tls_parse_certificate_authorities, tls_parse_certificate_authorities, + tls_construct_certificate_authorities, + tls_construct_certificate_authorities, NULL, + }, { /* Must be immediately before pre_shared_key */ - /* TODO(TLS1.3): Fix me */ TLSEXT_TYPE_padding, EXT_CLIENT_HELLO, NULL, @@ -288,7 +325,7 @@ static const EXTENSION_DEFINITION ext_defs[] = { * Verify whether we are allowed to use the extension |type| in the current * |context|. Returns 1 to indicate the extension is allowed or unknown or 0 to * indicate the extension is not allowed. If returning 1 then |*found| is set to - * 1 if we found a definition for the extension, and |*idx| is set to its index + * the definition for the extension we found. */ static int verify_extension(SSL *s, unsigned int context, unsigned int type, custom_ext_methods *meths, RAW_EXTENSION *rawexlist, @@ -377,10 +414,11 @@ static int extension_is_relevant(SSL *s, unsigned int extctx, * extensions that we know about. We ignore others. */ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, - RAW_EXTENSION **res, int *al) + RAW_EXTENSION **res, int *al, size_t *len) { PACKET extensions = *packet; size_t i = 0; + size_t num_exts; custom_ext_methods *exts = NULL; RAW_EXTENSION *raw_extensions = NULL; const EXTENSION_DEFINITION *thisexd; @@ -398,9 +436,8 @@ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, exts = &s->cert->cli_ext; } - raw_extensions = OPENSSL_zalloc((OSSL_NELEM(ext_defs) - + (exts != NULL ? exts->meths_count : 0)) - * sizeof(*raw_extensions)); + num_exts = OSSL_NELEM(ext_defs) + (exts != NULL ? exts->meths_count : 0); + raw_extensions = OPENSSL_zalloc(num_exts * sizeof(*raw_extensions)); if (raw_extensions == NULL) { *al = SSL_AD_INTERNAL_ERROR; SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_MALLOC_FAILURE); @@ -420,10 +457,14 @@ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, } /* * Verify this extension is allowed. We only check duplicates for - * extensions that we recognise. + * extensions that we recognise. We also have a special case for the + * PSK extension, which must be the last one in the ClientHello. */ if (!verify_extension(s, context, type, exts, raw_extensions, &thisex) - || (thisex != NULL && thisex->present == 1)) { + || (thisex != NULL && thisex->present == 1) + || (type == TLSEXT_TYPE_psk + && (context & EXT_CLIENT_HELLO) != 0 + && PACKET_remaining(&extensions) != 0)) { SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION); *al = SSL_AD_ILLEGAL_PARAMETER; goto err; @@ -449,6 +490,8 @@ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, } *res = raw_extensions; + if (len != NULL) + *len = num_exts; return 1; err: @@ -471,7 +514,8 @@ int tls_parse_extension(SSL *s, TLSEXT_INDEX idx, int context, RAW_EXTENSION *exts, X509 *x, size_t chainidx, int *al) { RAW_EXTENSION *currext = &exts[idx]; - int (*parser)(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) = NULL; + int (*parser)(SSL *s, PACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al) = NULL; /* Skip if the extension is not present */ if (!currext->present) @@ -500,7 +544,7 @@ int tls_parse_extension(SSL *s, TLSEXT_INDEX idx, int context, parser = s->server ? extdef->parse_ctos : extdef->parse_stoc; if (parser != NULL) - return parser(s, &currext->data, x, chainidx, al); + return parser(s, &currext->data, context, x, chainidx, al); /* * If the parser is NULL we fall through to the custom extension @@ -634,8 +678,8 @@ int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context, } for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs); i++, thisexd++) { - int (*construct)(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, - int *al); + int (*construct)(SSL *s, WPACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al); /* Skip if not relevant for our context */ if ((thisexd->context & context) == 0) @@ -662,7 +706,7 @@ int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context, || construct == NULL) continue; - if (!construct(s, pkt, x, chainidx, &tmpal)) + if (!construct(s, pkt, context, x, chainidx, &tmpal)) goto err; } @@ -737,10 +781,10 @@ static int final_server_name(SSL *s, unsigned int context, int sent, if (s->ctx != NULL && s->ctx->ext.servername_cb != 0) ret = s->ctx->ext.servername_cb(s, &altmp, s->ctx->ext.servername_arg); - else if (s->initial_ctx != NULL - && s->initial_ctx->ext.servername_cb != 0) - ret = s->initial_ctx->ext.servername_cb(s, &altmp, - s->initial_ctx->ext.servername_arg); + else if (s->session_ctx != NULL + && s->session_ctx->ext.servername_cb != 0) + ret = s->session_ctx->ext.servername_cb(s, &altmp, + s->session_ctx->ext.servername_arg); switch (ret) { case SSL_TLSEXT_ERR_ALERT_FATAL: @@ -841,8 +885,8 @@ static int init_alpn(SSL *s, unsigned int context) { OPENSSL_free(s->s3->alpn_selected); s->s3->alpn_selected = NULL; + s->s3->alpn_selected_len = 0; if (s->server) { - s->s3->alpn_selected_len = 0; OPENSSL_free(s->s3->alpn_proposed); s->s3->alpn_proposed = NULL; s->s3->alpn_proposed_len = 0; @@ -906,7 +950,7 @@ static int init_srp(SSL *s, unsigned int context) static int init_etm(SSL *s, unsigned int context) { - s->s3->flags &= ~TLS1_FLAGS_ENCRYPT_THEN_MAC; + s->ext.use_etm = 0; return 1; } @@ -937,6 +981,47 @@ static int final_ems(SSL *s, unsigned int context, int sent, int *al) return 1; } +static int init_certificate_authorities(SSL *s, unsigned int context) +{ + sk_X509_NAME_pop_free(s->s3->tmp.peer_ca_names, X509_NAME_free); + s->s3->tmp.peer_ca_names = NULL; + return 1; +} + +static int tls_construct_certificate_authorities(SSL *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx, int *al) +{ + const STACK_OF(X509_NAME) *ca_sk = SSL_get0_CA_list(s); + + if (ca_sk == NULL || sk_X509_NAME_num(ca_sk) == 0) + return 1; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_certificate_authorities) + || !WPACKET_start_sub_packet_u16(pkt) + || !construct_ca_names(s, pkt) + || !WPACKET_close(pkt)) { + SSLerr(SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES, + ERR_R_INTERNAL_ERROR); + return 0; + } + + return 1; +} + +static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx, int *al) +{ + if (!parse_ca_names(s, pkt, al)) + return 0; + if (PACKET_remaining(pkt) != 0) { + *al = SSL_AD_DECODE_ERROR; + return 0; + } + return 1; +} + #ifndef OPENSSL_NO_SRTP static int init_srtp(SSL *s, unsigned int context) { @@ -958,7 +1043,7 @@ static int final_sig_algs(SSL *s, unsigned int context, int sent, int *al) return 1; } - +#ifndef OPENSSL_NO_EC static int final_key_share(SSL *s, unsigned int context, int sent, int *al) { if (!SSL_IS_TLS13(s)) @@ -966,22 +1051,102 @@ static int final_key_share(SSL *s, unsigned int context, int sent, int *al) /* * If + * we are a client + * AND * we have no key_share * AND * (we are not resuming * OR the kex_mode doesn't allow non key_share resumes) * THEN - * fail + * fail; */ - if (((s->server && s->s3->peer_tmp == NULL) || (!s->server && !sent)) + if (!s->server + && !sent && (!s->hit || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0)) { - /* No suitable share */ - /* TODO(TLS1.3): Send a HelloRetryRequest */ + /* Nothing left we can do - just fail */ *al = SSL_AD_HANDSHAKE_FAILURE; SSLerr(SSL_F_FINAL_KEY_SHARE, SSL_R_NO_SUITABLE_KEY_SHARE); return 0; } + /* + * If + * we are a server + * AND + * we have no key_share + * THEN + * If + * we didn't already send a HelloRetryRequest + * AND + * the client sent a key_share extension + * AND + * (we are not resuming + * OR the kex_mode allows key_share resumes) + * AND + * a shared group exists + * THEN + * send a HelloRetryRequest + * ELSE If + * we are not resuming + * OR + * the kex_mode doesn't allow non key_share resumes + * THEN + * fail; + */ + if (s->server && s->s3->peer_tmp == NULL) { + /* No suitable share */ + if (s->hello_retry_request == 0 && sent + && (!s->hit + || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE) + != 0)) { + const unsigned char *pcurves, *pcurvestmp, *clntcurves; + size_t num_curves, clnt_num_curves, i; + unsigned int group_id = 0; + + /* Check if a shared group exists */ + + /* Get the clients list of supported groups. */ + if (!tls1_get_curvelist(s, 1, &clntcurves, &clnt_num_curves)) { + *al = SSL_AD_INTERNAL_ERROR; + SSLerr(SSL_F_FINAL_KEY_SHARE, ERR_R_INTERNAL_ERROR); + return 0; + } + + /* Get our list of available groups */ + if (!tls1_get_curvelist(s, 0, &pcurves, &num_curves)) { + *al = SSL_AD_INTERNAL_ERROR; + SSLerr(SSL_F_FINAL_KEY_SHARE, ERR_R_INTERNAL_ERROR); + return 0; + } + + /* Find the first group we allow that is also in client's list */ + for (i = 0, pcurvestmp = pcurves; i < num_curves; + i++, pcurvestmp += 2) { + group_id = bytestogroup(pcurvestmp); + + if (check_in_list(s, group_id, clntcurves, clnt_num_curves, 1)) + break; + } + + if (i < num_curves) { + /* A shared group exists so send a HelloRetryRequest */ + s->s3->group_id = group_id; + s->hello_retry_request = 1; + return 1; + } + } + if (!s->hit + || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0) { + /* Nothing left we can do - just fail */ + *al = SSL_AD_HANDSHAKE_FAILURE; + SSLerr(SSL_F_FINAL_KEY_SHARE, SSL_R_NO_SUITABLE_KEY_SHARE); + return 0; + } + } + + /* We have a key_share so don't send any more HelloRetryRequest messages */ + if (s->server) + s->hello_retry_request = 0; /* * For a client side resumption with no key_share we need to generate @@ -996,11 +1161,11 @@ static int final_key_share(SSL *s, unsigned int context, int sent, int *al) return 1; } +#endif static int init_psk_kex_modes(SSL *s, unsigned int context) { s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_NONE; - return 1; } @@ -1014,7 +1179,7 @@ int tls_psk_do_binder(SSL *s, const EVP_MD *md, const unsigned char *msgstart, unsigned char hash[EVP_MAX_MD_SIZE], binderkey[EVP_MAX_MD_SIZE]; unsigned char finishedkey[EVP_MAX_MD_SIZE], tmpbinder[EVP_MAX_MD_SIZE]; const char resumption_label[] = "resumption psk binder key"; - size_t hashsize = EVP_MD_size(md), bindersize; + size_t bindersize, hashsize = EVP_MD_size(md); int ret = -1; /* Generate the early_secret */ @@ -1052,13 +1217,52 @@ int tls_psk_do_binder(SSL *s, const EVP_MD *md, const unsigned char *msgstart, goto err; } + if (EVP_DigestInit_ex(mctx, md, NULL) <= 0) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; + } + /* - * Get a hash of the ClientHello up to the start of the binders. - * TODO(TLS1.3): This will need to be tweaked when we implement - * HelloRetryRequest to include the digest of the previous messages here. + * Get a hash of the ClientHello up to the start of the binders. If we are + * following a HelloRetryRequest then this includes the hash of the first + * ClientHello and the HelloRetryRequest itself. */ - if (EVP_DigestInit_ex(mctx, md, NULL) <= 0 - || EVP_DigestUpdate(mctx, msgstart, binderoffset) <= 0 + if (s->hello_retry_request) { + size_t hdatalen; + void *hdata; + + hdatalen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata); + if (hdatalen <= 0) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, SSL_R_BAD_HANDSHAKE_LENGTH); + goto err; + } + + /* + * For servers the handshake buffer data will include the second + * ClientHello - which we don't want - so we need to take that bit off. + */ + if (s->server) { + PACKET hashprefix, msg; + + /* Find how many bytes are left after the first two messages */ + if (!PACKET_buf_init(&hashprefix, hdata, hdatalen) + || !PACKET_forward(&hashprefix, 1) + || !PACKET_get_length_prefixed_3(&hashprefix, &msg) + || !PACKET_forward(&hashprefix, 1) + || !PACKET_get_length_prefixed_3(&hashprefix, &msg)) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; + } + hdatalen -= PACKET_remaining(&hashprefix); + } + + if (EVP_DigestUpdate(mctx, hdata, hdatalen) <= 0) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; + } + } + + if (EVP_DigestUpdate(mctx, msgstart, binderoffset) <= 0 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) { SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); goto err; @@ -1097,3 +1301,32 @@ int tls_psk_do_binder(SSL *s, const EVP_MD *md, const unsigned char *msgstart, return ret; } + +static int final_early_data(SSL *s, unsigned int context, int sent, int *al) +{ + if (!s->server || !sent) + return 1; + + if (s->max_early_data == 0 + || !s->hit + || s->session->ext.tick_identity != 0 + || s->early_data_state != SSL_EARLY_DATA_ACCEPTING + || !s->ext.early_data_ok + || s->hello_retry_request + || s->s3->alpn_selected_len != s->session->ext.alpn_selected_len + || (s->s3->alpn_selected_len > 0 + && memcmp(s->s3->alpn_selected, s->session->ext.alpn_selected, + s->s3->alpn_selected_len) != 0)) { + s->ext.early_data = SSL_EARLY_DATA_REJECTED; + } else { + s->ext.early_data = SSL_EARLY_DATA_ACCEPTED; + + if (!tls13_change_cipher_state(s, + SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_SERVER_READ)) { + *al = SSL_AD_INTERNAL_ERROR; + return 0; + } + } + + return 1; +}