diff options
Diffstat (limited to 'crypto/openssl/ssl/statem/extensions_srvr.c')
| -rw-r--r-- | crypto/openssl/ssl/statem/extensions_srvr.c | 2422 |
1 files changed, 2422 insertions, 0 deletions
diff --git a/crypto/openssl/ssl/statem/extensions_srvr.c b/crypto/openssl/ssl/statem/extensions_srvr.c new file mode 100644 index 000000000000..1a09913ad63f --- /dev/null +++ b/crypto/openssl/ssl/statem/extensions_srvr.c @@ -0,0 +1,2422 @@ +/* + * Copyright 2016-2025 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the Apache License 2.0 (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html + */ + +#include <openssl/ocsp.h> +#include "../ssl_local.h" +#include "statem_local.h" +#include "internal/cryptlib.h" +#include "internal/ssl_unwrap.h" + +#define COOKIE_STATE_FORMAT_VERSION 1 + +/* + * 2 bytes for packet length, 2 bytes for format version, 2 bytes for + * protocol version, 2 bytes for group id, 2 bytes for cipher id, 1 byte for + * key_share present flag, 8 bytes for timestamp, 2 bytes for the hashlen, + * EVP_MAX_MD_SIZE for transcript hash, 1 byte for app cookie length, app cookie + * length bytes, SHA256_DIGEST_LENGTH bytes for the HMAC of the whole thing. + */ +#define MAX_COOKIE_SIZE (2 + 2 + 2 + 2 + 2 + 1 + 8 + 2 + EVP_MAX_MD_SIZE + 1 \ + + SSL_COOKIE_LENGTH + SHA256_DIGEST_LENGTH) + +/* + * Message header + 2 bytes for protocol version + number of random bytes + + * + 1 byte for legacy session id length + number of bytes in legacy session id + * + 2 bytes for ciphersuite + 1 byte for legacy compression + * + 2 bytes for extension block length + 6 bytes for key_share extension + * + 4 bytes for cookie extension header + the number of bytes in the cookie + */ +#define MAX_HRR_SIZE (SSL3_HM_HEADER_LENGTH + 2 + SSL3_RANDOM_SIZE + 1 \ + + SSL_MAX_SSL_SESSION_ID_LENGTH + 2 + 1 + 2 + 6 + 4 \ + + MAX_COOKIE_SIZE) + +/* + * Parse the client's renegotiation binding and abort if it's not right + */ +int tls_parse_ctos_renegotiate(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + unsigned int ilen; + const unsigned char *data; + int ok; + + /* Parse the length byte */ + if (!PACKET_get_1(pkt, &ilen) + || !PACKET_get_bytes(pkt, &data, ilen)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RENEGOTIATION_ENCODING_ERR); + return 0; + } + + /* Check that the extension matches */ + if (ilen != s->s3.previous_client_finished_len) { + SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_RENEGOTIATION_MISMATCH); + return 0; + } + + ok = memcmp(data, s->s3.previous_client_finished, + s->s3.previous_client_finished_len); +#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION + if (ok) { + if ((data[0] ^ s->s3.previous_client_finished[0]) != 0xFF) { + ok = 0; + } + } +#endif + if (ok) { + SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_RENEGOTIATION_MISMATCH); + return 0; + } + + s->s3.send_connection_binding = 1; + + return 1; +} + +/*- + * The servername extension is treated as follows: + * + * - Only the hostname type is supported with a maximum length of 255. + * - The servername is rejected if too long or if it contains zeros, + * in which case an fatal alert is generated. + * - The servername field is maintained together with the session cache. + * - When a session is resumed, the servername call back invoked in order + * to allow the application to position itself to the right context. + * - The servername is acknowledged if it is new for a session or when + * it is identical to a previously used for the same session. + * Applications can control the behaviour. They can at any time + * set a 'desirable' servername for a new SSL object. This can be the + * case for example with HTTPS when a Host: header field is received and + * a renegotiation is requested. In this case, a possible servername + * presented in the new client hello is only acknowledged if it matches + * the value of the Host: field. + * - Applications must use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION + * if they provide for changing an explicit servername context for the + * session, i.e. when the session has been established with a servername + * extension. + * - On session reconnect, the servername extension may be absent. + */ +int tls_parse_ctos_server_name(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, X509 *x, size_t chainidx) +{ + unsigned int servname_type; + PACKET sni, hostname; + + if (!PACKET_as_length_prefixed_2(pkt, &sni) + /* ServerNameList must be at least 1 byte long. */ + || PACKET_remaining(&sni) == 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + /* + * Although the intent was for server_name to be extensible, RFC 4366 + * was not clear about it; and so OpenSSL among other implementations, + * always and only allows a 'host_name' name types. + * RFC 6066 corrected the mistake but adding new name types + * is nevertheless no longer feasible, so act as if no other + * SNI types can exist, to simplify parsing. + * + * Also note that the RFC permits only one SNI value per type, + * i.e., we can only have a single hostname. + */ + if (!PACKET_get_1(&sni, &servname_type) + || servname_type != TLSEXT_NAMETYPE_host_name + || !PACKET_as_length_prefixed_2(&sni, &hostname)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + /* + * In TLSv1.2 and below the SNI is associated with the session. In TLSv1.3 + * we always use the SNI value from the handshake. + */ + if (!s->hit || SSL_CONNECTION_IS_TLS13(s)) { + if (PACKET_remaining(&hostname) > TLSEXT_MAXLEN_host_name) { + SSLfatal(s, SSL_AD_UNRECOGNIZED_NAME, SSL_R_BAD_EXTENSION); + return 0; + } + + if (PACKET_contains_zero_byte(&hostname)) { + SSLfatal(s, SSL_AD_UNRECOGNIZED_NAME, SSL_R_BAD_EXTENSION); + return 0; + } + + /* + * Store the requested SNI in the SSL as temporary storage. + * If we accept it, it will get stored in the SSL_SESSION as well. + */ + OPENSSL_free(s->ext.hostname); + s->ext.hostname = NULL; + if (!PACKET_strndup(&hostname, &s->ext.hostname)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + + s->servername_done = 1; + } else { + /* + * In TLSv1.2 and below we should check if the SNI is consistent between + * the initial handshake and the resumption. In TLSv1.3 SNI is not + * associated with the session. + */ + s->servername_done = (s->session->ext.hostname != NULL) + && PACKET_equal(&hostname, s->session->ext.hostname, + strlen(s->session->ext.hostname)); + } + + return 1; +} + +int tls_parse_ctos_maxfragmentlen(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + unsigned int value; + + if (PACKET_remaining(pkt) != 1 || !PACKET_get_1(pkt, &value)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + /* Received |value| should be a valid max-fragment-length code. */ + if (!IS_MAX_FRAGMENT_LENGTH_EXT_VALID(value)) { + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, + SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH); + return 0; + } + + /* + * When doing a full handshake or a renegotiation max_fragment_len_mode will + * be TLSEXT_max_fragment_length_UNSPECIFIED + * + * In case of a resumption max_fragment_len_mode will be one of + * TLSEXT_max_fragment_length_DISABLED, TLSEXT_max_fragment_length_512, + * TLSEXT_max_fragment_length_1024, TLSEXT_max_fragment_length_2048. + * TLSEXT_max_fragment_length_4096 + * + * RFC 6066: The negotiated length applies for the duration of the session + * including session resumptions. + * + * So we only set the value in case it is unspecified. + */ + if (s->session->ext.max_fragment_len_mode == TLSEXT_max_fragment_length_UNSPECIFIED) + /* + * Store it in session, so it'll become binding for us + * and we'll include it in a next Server Hello. + */ + s->session->ext.max_fragment_len_mode = value; + + return 1; +} + +#ifndef OPENSSL_NO_SRP +int tls_parse_ctos_srp(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ + PACKET srp_I; + + if (!PACKET_as_length_prefixed_1(pkt, &srp_I) + || PACKET_contains_zero_byte(&srp_I)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (!PACKET_strndup(&srp_I, &s->srp_ctx.login)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + + return 1; +} +#endif + +int tls_parse_ctos_ec_pt_formats(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + PACKET ec_point_format_list; + + if (!PACKET_as_length_prefixed_1(pkt, &ec_point_format_list) + || PACKET_remaining(&ec_point_format_list) == 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (!s->hit) { + if (!PACKET_memdup(&ec_point_format_list, + &s->ext.peer_ecpointformats, + &s->ext.peer_ecpointformats_len)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + } + + return 1; +} + +int tls_parse_ctos_session_ticket(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + if (s->ext.session_ticket_cb && + !s->ext.session_ticket_cb(SSL_CONNECTION_GET_USER_SSL(s), + PACKET_data(pkt), PACKET_remaining(pkt), + s->ext.session_ticket_cb_arg)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + + return 1; +} + +int tls_parse_ctos_sig_algs_cert(SSL_CONNECTION *s, PACKET *pkt, + ossl_unused unsigned int context, + ossl_unused X509 *x, + ossl_unused size_t chainidx) +{ + PACKET supported_sig_algs; + + if (!PACKET_as_length_prefixed_2(pkt, &supported_sig_algs) + || PACKET_remaining(&supported_sig_algs) == 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + /* + * We use this routine on both clients and servers, and when clients + * get asked for PHA we need to always save the sigalgs regardless + * of whether it was a resumption or not. + */ + if ((!s->server || (s->server && !s->hit)) + && !tls1_save_sigalgs(s, &supported_sig_algs, 1)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + return 1; +} + +int tls_parse_ctos_sig_algs(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, X509 *x, size_t chainidx) +{ + PACKET supported_sig_algs; + + if (!PACKET_as_length_prefixed_2(pkt, &supported_sig_algs) + || PACKET_remaining(&supported_sig_algs) == 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + /* + * We use this routine on both clients and servers, and when clients + * get asked for PHA we need to always save the sigalgs regardless + * of whether it was a resumption or not. + */ + if ((!s->server || (s->server && !s->hit)) + && !tls1_save_sigalgs(s, &supported_sig_algs, 0)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + return 1; +} + +#ifndef OPENSSL_NO_OCSP +int tls_parse_ctos_status_request(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + PACKET responder_id_list, exts; + + /* We ignore this in a resumption handshake */ + if (s->hit) + return 1; + + /* Not defined if we get one of these in a client Certificate */ + if (x != NULL) + return 1; + + if (!PACKET_get_1(pkt, (unsigned int *)&s->ext.status_type)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp) { + /* + * We don't know what to do with any other type so ignore it. + */ + s->ext.status_type = TLSEXT_STATUSTYPE_nothing; + return 1; + } + + if (!PACKET_get_length_prefixed_2 (pkt, &responder_id_list)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + /* + * We remove any OCSP_RESPIDs from a previous handshake + * to prevent unbounded memory growth - CVE-2016-6304 + */ + sk_OCSP_RESPID_pop_free(s->ext.ocsp.ids, OCSP_RESPID_free); + if (PACKET_remaining(&responder_id_list) > 0) { + s->ext.ocsp.ids = sk_OCSP_RESPID_new_null(); + if (s->ext.ocsp.ids == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB); + return 0; + } + } else { + s->ext.ocsp.ids = NULL; + } + + while (PACKET_remaining(&responder_id_list) > 0) { + OCSP_RESPID *id; + PACKET responder_id; + const unsigned char *id_data; + + if (!PACKET_get_length_prefixed_2(&responder_id_list, &responder_id) + || PACKET_remaining(&responder_id) == 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + id_data = PACKET_data(&responder_id); + id = d2i_OCSP_RESPID(NULL, &id_data, + (int)PACKET_remaining(&responder_id)); + if (id == NULL) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (id_data != PACKET_end(&responder_id)) { + OCSP_RESPID_free(id); + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + + return 0; + } + + if (!sk_OCSP_RESPID_push(s->ext.ocsp.ids, id)) { + OCSP_RESPID_free(id); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + + return 0; + } + } + + /* Read in request_extensions */ + if (!PACKET_as_length_prefixed_2(pkt, &exts)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (PACKET_remaining(&exts) > 0) { + const unsigned char *ext_data = PACKET_data(&exts); + + sk_X509_EXTENSION_pop_free(s->ext.ocsp.exts, + X509_EXTENSION_free); + s->ext.ocsp.exts = + d2i_X509_EXTENSIONS(NULL, &ext_data, (int)PACKET_remaining(&exts)); + if (s->ext.ocsp.exts == NULL || ext_data != PACKET_end(&exts)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + } + + return 1; +} +#endif + +#ifndef OPENSSL_NO_NEXTPROTONEG +int tls_parse_ctos_npn(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ + /* + * We shouldn't accept this extension on a + * renegotiation. + */ + if (SSL_IS_FIRST_HANDSHAKE(s)) + s->s3.npn_seen = 1; + + return 1; +} +#endif + +/* + * Save the ALPN extension in a ClientHello.|pkt| holds the contents of the ALPN + * extension, not including type and length. Returns: 1 on success, 0 on error. + */ +int tls_parse_ctos_alpn(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ + PACKET protocol_list, save_protocol_list, protocol; + + if (!SSL_IS_FIRST_HANDSHAKE(s)) + return 1; + + if (!PACKET_as_length_prefixed_2(pkt, &protocol_list) + || PACKET_remaining(&protocol_list) < 2) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + save_protocol_list = protocol_list; + do { + /* Protocol names can't be empty. */ + if (!PACKET_get_length_prefixed_1(&protocol_list, &protocol) + || PACKET_remaining(&protocol) == 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + } while (PACKET_remaining(&protocol_list) != 0); + + OPENSSL_free(s->s3.alpn_proposed); + s->s3.alpn_proposed = NULL; + s->s3.alpn_proposed_len = 0; + if (!PACKET_memdup(&save_protocol_list, + &s->s3.alpn_proposed, &s->s3.alpn_proposed_len)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + + return 1; +} + +#ifndef OPENSSL_NO_SRTP +int tls_parse_ctos_use_srtp(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, X509 *x, size_t chainidx) +{ + STACK_OF(SRTP_PROTECTION_PROFILE) *srvr; + unsigned int ct, mki_len, id; + int i, srtp_pref; + PACKET subpkt; + SSL *ssl = SSL_CONNECTION_GET_SSL(s); + + /* Ignore this if we have no SRTP profiles */ + if (SSL_get_srtp_profiles(ssl) == NULL) + return 1; + + /* Pull off the length of the cipher suite list and check it is even */ + if (!PACKET_get_net_2(pkt, &ct) || (ct & 1) != 0 + || !PACKET_get_sub_packet(pkt, &subpkt, ct)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, + SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); + return 0; + } + + srvr = SSL_get_srtp_profiles(ssl); + s->srtp_profile = NULL; + /* Search all profiles for a match initially */ + srtp_pref = sk_SRTP_PROTECTION_PROFILE_num(srvr); + + while (PACKET_remaining(&subpkt)) { + if (!PACKET_get_net_2(&subpkt, &id)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, + SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); + return 0; + } + + /* + * Only look for match in profiles of higher preference than + * current match. + * If no profiles have been have been configured then this + * does nothing. + */ + for (i = 0; i < srtp_pref; i++) { + SRTP_PROTECTION_PROFILE *sprof = + sk_SRTP_PROTECTION_PROFILE_value(srvr, i); + + if (sprof->id == id) { + s->srtp_profile = sprof; + srtp_pref = i; + break; + } + } + } + + /* Now extract the MKI value as a sanity check, but discard it for now */ + if (!PACKET_get_1(pkt, &mki_len)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, + SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); + return 0; + } + + if (!PACKET_forward(pkt, mki_len) + || PACKET_remaining(pkt)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_SRTP_MKI_VALUE); + return 0; + } + + return 1; +} +#endif + +int tls_parse_ctos_etm(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ + if (!(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)) + s->ext.use_etm = 1; + + return 1; +} + +/* + * Process a psk_kex_modes extension received in the ClientHello. |pkt| contains + * the raw PACKET data for the extension. Returns 1 on success or 0 on failure. + */ +int tls_parse_ctos_psk_kex_modes(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ +#ifndef OPENSSL_NO_TLS1_3 + PACKET psk_kex_modes; + unsigned int mode; + + if (!PACKET_as_length_prefixed_1(pkt, &psk_kex_modes) + || PACKET_remaining(&psk_kex_modes) == 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + while (PACKET_get_1(&psk_kex_modes, &mode)) { + if (mode == TLSEXT_KEX_MODE_KE_DHE) + s->ext.psk_kex_mode |= TLSEXT_KEX_MODE_FLAG_KE_DHE; + else if (mode == TLSEXT_KEX_MODE_KE + && (s->options & SSL_OP_ALLOW_NO_DHE_KEX) != 0) + s->ext.psk_kex_mode |= TLSEXT_KEX_MODE_FLAG_KE; + } + + if (((s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) != 0) + && (s->options & SSL_OP_PREFER_NO_DHE_KEX) != 0) { + + /* + * If NO_DHE is supported and preferred, then we only remember this + * mode. DHE PSK will not be used for sure, because in any case where + * it would be supported (i.e. if a key share is present), NO_DHE would + * be supported as well. As the latter is preferred it would be + * chosen. By removing DHE PSK here, we don't have to deal with the + * SSL_OP_PREFER_NO_DHE_KEX option in any other place. + */ + s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_KE; + } + +#endif + + return 1; +} + +/* + * Use function tls_parse_ctos_key_share with helper functions extract_keyshares, + * check_overlap and tls_accept_ksgroup to parse the key_share extension(s) + * received in the ClientHello and to select the group used of the key exchange + */ + +#ifndef OPENSSL_NO_TLS1_3 +/* + * Accept a key share group by setting the related variables in s->s3 and + * by generating a pubkey for this group + */ +static int tls_accept_ksgroup(SSL_CONNECTION *s, uint16_t ksgroup, PACKET *encoded_pubkey) +{ + /* Accept the key share group */ + s->s3.group_id = ksgroup; + s->s3.group_id_candidate = ksgroup; + /* Cache the selected group ID in the SSL_SESSION */ + s->session->kex_group = ksgroup; + if ((s->s3.peer_tmp = ssl_generate_param_group(s, ksgroup)) == NULL) { + SSLfatal(s, + SSL_AD_INTERNAL_ERROR, + SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS); + return 0; + } + if (tls13_set_encoded_pub_key(s->s3.peer_tmp, + PACKET_data(encoded_pubkey), + PACKET_remaining(encoded_pubkey)) <= 0) { + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_ECPOINT); + return 0; + } + return 1; +} + +# define GROUPLIST_INCREMENT 32 /* Memory allocation chunk size (nominally 64 Bytes chunks) */ + +typedef enum KS_EXTRACTION_RESULT { + EXTRACTION_FAILURE, + EXTRACTION_SUCCESS, + EXTRACTION_SUCCESS_HRR +} KS_EXTRACTION_RESULT; + +static KS_EXTRACTION_RESULT extract_keyshares(SSL_CONNECTION *s, PACKET *key_share_list, + const uint16_t *clntgroups, size_t clnt_num_groups, + const uint16_t *srvrgroups, size_t srvr_num_groups, + uint16_t **keyshares_arr, PACKET **encoded_pubkey_arr, + size_t *keyshares_cnt, size_t *keyshares_max) +{ + PACKET encoded_pubkey; + size_t key_share_pos = 0; + size_t previous_key_share_pos = 0; + unsigned int group_id = 0; + + /* Prepare memory to hold the extracted key share groups and related pubkeys */ + *keyshares_arr = OPENSSL_malloc(*keyshares_max * sizeof(**keyshares_arr)); + if (*keyshares_arr == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + goto failure; + } + *encoded_pubkey_arr = OPENSSL_malloc(*keyshares_max * sizeof(**encoded_pubkey_arr)); + if (*encoded_pubkey_arr == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + goto failure; + } + + while (PACKET_remaining(key_share_list) > 0) { + /* Get the group_id for the current share and its encoded_pubkey */ + if (!PACKET_get_net_2(key_share_list, &group_id) + || !PACKET_get_length_prefixed_2(key_share_list, &encoded_pubkey) + || PACKET_remaining(&encoded_pubkey) == 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + goto failure; + } + + /* + * If we sent an HRR then the key_share sent back MUST be for the group + * we requested, and must be the only key_share sent. + */ + if (s->s3.group_id != 0 + && (group_id != s->s3.group_id + || PACKET_remaining(key_share_list) != 0)) { + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE); + goto failure; + } + + /* + * Check if this share is in supported_groups sent from client + * RFC 8446 also mandates that clients send keyshares in the same + * order as listed in the supported groups extension, but its not + * required that the server check that, and some clients violate this + * so instead of failing the connection when that occurs, log a trace + * message indicating the client discrepancy. + */ + if (!check_in_list(s, group_id, clntgroups, clnt_num_groups, 0, &key_share_pos)) { + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE); + goto failure; + } + + if (key_share_pos < previous_key_share_pos) + OSSL_TRACE1(TLS, "key share group id %d is out of RFC 8446 order\n", group_id); + + previous_key_share_pos = key_share_pos; + + if (s->s3.group_id != 0) { + /* + * We have sent a HRR, and the key share we got back is + * the one we expected and is the only key share and is + * in the list of supported_groups (checked + * above already), hence we accept this key share group + */ + if (!tls_accept_ksgroup(s, s->s3.group_id, &encoded_pubkey)) + goto failure; /* SSLfatal already called */ + /* We have selected a key share group via HRR, hence we're done here */ + return EXTRACTION_SUCCESS_HRR; + } + + /* + * We tolerate but ignore a group id that we don't think is + * suitable for TLSv1.3 or which is not supported by the server + */ + if (!check_in_list(s, group_id, srvrgroups, srvr_num_groups, 1, NULL) + || !tls_group_allowed(s, group_id, SSL_SECOP_CURVE_SUPPORTED) + || !tls_valid_group(s, group_id, TLS1_3_VERSION, TLS1_3_VERSION, + 0, NULL)) { + /* Share not suitable or not supported, check next share */ + continue; + } + + /* Memorize this key share group ID and its encoded point */ + (*keyshares_arr)[*keyshares_cnt] = group_id; + (*encoded_pubkey_arr)[(*keyshares_cnt)++] = encoded_pubkey; + + /* + * Memory management (remark: While limiting the client to only allow + * a maximum of OPENSSL_CLIENT_MAX_KEY_SHARES to be sent, the server can + * handle any number of key shares) + */ + if (*keyshares_cnt == *keyshares_max) { + PACKET *tmp_pkt; + uint16_t *tmp = + OPENSSL_realloc(*keyshares_arr, + (*keyshares_max + GROUPLIST_INCREMENT) * sizeof(**keyshares_arr)); + + if (tmp == NULL) + goto failure; + *keyshares_arr = tmp; + tmp_pkt = + OPENSSL_realloc(*encoded_pubkey_arr, + (*keyshares_max + GROUPLIST_INCREMENT) * + sizeof(**encoded_pubkey_arr)); + if (tmp_pkt == NULL) + goto failure; + *encoded_pubkey_arr = tmp_pkt; + *keyshares_max += GROUPLIST_INCREMENT; + } + + } + + return EXTRACTION_SUCCESS; + +failure: + /* Fatal error -> free any allocated memory and return 0 */ + OPENSSL_free(*keyshares_arr); + OPENSSL_free(*encoded_pubkey_arr); + return EXTRACTION_FAILURE; +} +#endif + +/* + * For each group in the priority list of groups, check if that group is + * also present in the secondary list; if so, select the first overlap and + * assign to selected_group and also set the related index in the candidate group list, + * or set selected_group to 0 if no overlap + */ +#ifndef OPENSSL_NO_TLS1_3 +static void check_overlap(SSL_CONNECTION *s, + const uint16_t *prio_groups, size_t prio_num_groups, + const uint16_t *candidate_groups, size_t candidate_num_groups, + int *prio_group_idx, int *candidate_group_idx, + uint16_t *selected_group) +{ + uint16_t current_group; + size_t group_idx = prio_num_groups; + size_t new_group_idx = 0; + + *candidate_group_idx = 0; + *prio_group_idx = 0; + *selected_group = 0; + + for (current_group = 0; current_group < candidate_num_groups; current_group++) { + if (!check_in_list(s, candidate_groups[current_group], prio_groups, + prio_num_groups, 1, &new_group_idx) + || !tls_group_allowed(s, candidate_groups[current_group], + SSL_SECOP_CURVE_SUPPORTED) + || !tls_valid_group(s, candidate_groups[current_group], TLS1_3_VERSION, + TLS1_3_VERSION, 0, NULL)) + /* No overlap or group not suitable, check next group */ + continue; + + /* + * is the found new_group_idx earlier in the priority list than + * initial or last group_idx? + */ + if (new_group_idx < group_idx) { + group_idx = new_group_idx; + *candidate_group_idx = current_group; + *prio_group_idx = group_idx; + *selected_group = prio_groups[group_idx]; + } + } +} +#endif + +int tls_parse_ctos_key_share(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, X509 *x, size_t chainidx) +{ +#ifndef OPENSSL_NO_TLS1_3 + PACKET key_share_list; + const uint16_t *clntgroups, *srvrgroups; + const size_t *srvrtuples; + uint16_t *first_group_in_tuple; + size_t clnt_num_groups, srvr_num_groups, srvr_num_tuples; + PACKET *encoded_pubkey_arr = NULL; + uint16_t *keyshares_arr = NULL; + size_t keyshares_cnt = 0; + size_t keyshares_max = GROUPLIST_INCREMENT; + /* We conservatively assume that we did not find a suitable group */ + uint16_t group_id_candidate = 0; + KS_EXTRACTION_RESULT ks_extraction_result; + size_t current_tuple; + int ret = 0; + + s->s3.group_id_candidate = 0; + if (s->hit && (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE) == 0) + return 1; + + /* Sanity check */ + if (s->s3.peer_tmp != NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + + if (!PACKET_as_length_prefixed_2(pkt, &key_share_list)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + return 0; + } + + /* Get list of server supported groups and the group tuples */ + tls1_get_supported_groups(s, &srvrgroups, &srvr_num_groups); + tls1_get_group_tuples(s, &srvrtuples, &srvr_num_tuples); + /* Get the clients list of supported groups. */ + tls1_get_peer_groups(s, &clntgroups, &clnt_num_groups); + + if (clnt_num_groups == 0) { + /* + * This can only happen if the supported_groups extension was not sent, + * because we verify that the length is non-zero when we process that + * extension. + */ + SSLfatal(s, SSL_AD_MISSING_EXTENSION, + SSL_R_MISSING_SUPPORTED_GROUPS_EXTENSION); + return 0; + } + + if (s->s3.group_id != 0 && PACKET_remaining(&key_share_list) == 0) { + /* + * If we set a group_id already, then we must have sent an HRR + * requesting a new key_share. If we haven't got one then that is an + * error + */ + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE); + return 0; + } + + /* We parse the key share extension and memorize the entries (after some checks) */ + ks_extraction_result = extract_keyshares(s, + &key_share_list, + clntgroups, clnt_num_groups, + srvrgroups, srvr_num_groups, + &keyshares_arr, &encoded_pubkey_arr, + &keyshares_cnt, &keyshares_max); + + if (ks_extraction_result == EXTRACTION_FAILURE) /* Fatal error during tests */ + return 0; /* Memory already freed and SSLfatal already called */ + if (ks_extraction_result == EXTRACTION_SUCCESS_HRR) /* Successful HRR */ + goto end; + + /* + * We now have the folowing lists available to make a decision for + * which group the server should use for key exchange : + * From client: clntgroups[clnt_num_groups], + * keyshares_arr[keyshares_cnt], encoded_pubkey_arr[keyshares_cnt] + * From server: srvrgroups[srvr_num_groups], srvrtuples[srvr_num_tuples] + * + * Group selection algorithm: + * For all tuples do: + * key share group(s) overlapping with current tuple? + * --> Yes: accept group_id for SH + * --> No: is any of the client supported_groups overlapping with current tuple? + * --> Yes: memorize group_id for HRR, break + * --> No: continue to check next tuple + * + * Remark: Selection priority different for client- or server-preference + */ + first_group_in_tuple = (uint16_t *)srvrgroups; + for (current_tuple = 0; current_tuple < srvr_num_tuples; current_tuple++) { + size_t number_of_groups_in_tuple = srvrtuples[current_tuple]; + int prio_group_idx = 0, candidate_group_idx = 0; + + /* Server or client preference ? */ + if (s->options & SSL_OP_CIPHER_SERVER_PREFERENCE) { + /* Server preference */ + /* Is there overlap with a key share group? */ + check_overlap(s, + first_group_in_tuple, number_of_groups_in_tuple, + keyshares_arr, keyshares_cnt, + &prio_group_idx, &candidate_group_idx, + &group_id_candidate); + if (group_id_candidate > 0) { /* Overlap found -> accept the key share group */ + if (!tls_accept_ksgroup(s, group_id_candidate, + &encoded_pubkey_arr[candidate_group_idx])) + goto err; /* SSLfatal already called */ + /* We have all info for a SH, hence we're done here */ + goto end; + } else { + /* + * There's no overlap with a key share, but is there at least a client + * supported_group overlapping with the current tuple? + */ + check_overlap(s, + first_group_in_tuple, number_of_groups_in_tuple, + clntgroups, clnt_num_groups, + &prio_group_idx, &candidate_group_idx, + &group_id_candidate); + if (group_id_candidate > 0) { + /* + * We did not have a key share overlap, but at least the supported + * groups overlap hence we can stop searching + * (and report group_id_candidate 'upward' for HRR) + */ + s->s3.group_id_candidate = group_id_candidate; + goto end; + } else { + /* + * Neither key share nor supported_groups overlap current + * tuple, hence we try the next tuple + */ + first_group_in_tuple = &first_group_in_tuple[number_of_groups_in_tuple]; + continue; + } + } + + } else { /* We have client preference */ + check_overlap(s, + keyshares_arr, keyshares_cnt, + first_group_in_tuple, number_of_groups_in_tuple, + &prio_group_idx, &candidate_group_idx, + &group_id_candidate); + if (group_id_candidate > 0) { + if (!tls_accept_ksgroup(s, group_id_candidate, &encoded_pubkey_arr[prio_group_idx])) + goto err; + goto end; + } else { + check_overlap(s, + clntgroups, clnt_num_groups, + first_group_in_tuple, number_of_groups_in_tuple, + &prio_group_idx, &candidate_group_idx, + &group_id_candidate); + if (group_id_candidate > 0) { + s->s3.group_id_candidate = group_id_candidate; + goto end; + } else { + first_group_in_tuple = &first_group_in_tuple[number_of_groups_in_tuple]; + continue; + } + } + } + } + +end: + ret = 1; + +err: + OPENSSL_free(keyshares_arr); + OPENSSL_free(encoded_pubkey_arr); + return ret; + +#endif + + return 1; +} + +int tls_parse_ctos_cookie(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ +#ifndef OPENSSL_NO_TLS1_3 + unsigned int format, version, key_share, group_id; + EVP_MD_CTX *hctx; + EVP_PKEY *pkey; + PACKET cookie, raw, chhash, appcookie; + WPACKET hrrpkt; + const unsigned char *data, *mdin, *ciphdata; + unsigned char hmac[SHA256_DIGEST_LENGTH]; + unsigned char hrr[MAX_HRR_SIZE]; + size_t rawlen, hmaclen, hrrlen, ciphlen; + uint64_t tm, now; + SSL *ssl = SSL_CONNECTION_GET_SSL(s); + SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); + + /* Ignore any cookie if we're not set up to verify it */ + if (sctx->verify_stateless_cookie_cb == NULL + || (s->s3.flags & TLS1_FLAGS_STATELESS) == 0) + return 1; + + if (!PACKET_as_length_prefixed_2(pkt, &cookie)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + return 0; + } + + raw = cookie; + data = PACKET_data(&raw); + rawlen = PACKET_remaining(&raw); + if (rawlen < SHA256_DIGEST_LENGTH + || !PACKET_forward(&raw, rawlen - SHA256_DIGEST_LENGTH)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + return 0; + } + mdin = PACKET_data(&raw); + + /* Verify the HMAC of the cookie */ + hctx = EVP_MD_CTX_create(); + pkey = EVP_PKEY_new_raw_private_key_ex(sctx->libctx, "HMAC", + sctx->propq, + s->session_ctx->ext.cookie_hmac_key, + sizeof(s->session_ctx->ext.cookie_hmac_key)); + if (hctx == NULL || pkey == NULL) { + EVP_MD_CTX_free(hctx); + EVP_PKEY_free(pkey); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); + return 0; + } + + hmaclen = SHA256_DIGEST_LENGTH; + if (EVP_DigestSignInit_ex(hctx, NULL, "SHA2-256", sctx->libctx, + sctx->propq, pkey, NULL) <= 0 + || EVP_DigestSign(hctx, hmac, &hmaclen, data, + rawlen - SHA256_DIGEST_LENGTH) <= 0 + || hmaclen != SHA256_DIGEST_LENGTH) { + EVP_MD_CTX_free(hctx); + EVP_PKEY_free(pkey); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + + EVP_MD_CTX_free(hctx); + EVP_PKEY_free(pkey); + + if (CRYPTO_memcmp(hmac, mdin, SHA256_DIGEST_LENGTH) != 0) { + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_COOKIE_MISMATCH); + return 0; + } + + if (!PACKET_get_net_2(&cookie, &format)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + return 0; + } + /* Check the cookie format is something we recognise. Ignore it if not */ + if (format != COOKIE_STATE_FORMAT_VERSION) + return 1; + + /* + * The rest of these checks really shouldn't fail since we have verified the + * HMAC above. + */ + + /* Check the version number is sane */ + if (!PACKET_get_net_2(&cookie, &version)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + return 0; + } + if (version != TLS1_3_VERSION) { + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, + SSL_R_BAD_PROTOCOL_VERSION_NUMBER); + return 0; + } + + if (!PACKET_get_net_2(&cookie, &group_id)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + return 0; + } + + ciphdata = PACKET_data(&cookie); + if (!PACKET_forward(&cookie, 2)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + return 0; + } + if (group_id != s->s3.group_id + || s->s3.tmp.new_cipher + != ssl_get_cipher_by_char(s, ciphdata, 0)) { + /* + * We chose a different cipher or group id this time around to what is + * in the cookie. Something must have changed. + */ + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_CIPHER); + return 0; + } + + if (!PACKET_get_1(&cookie, &key_share) + || !PACKET_get_net_8(&cookie, &tm) + || !PACKET_get_length_prefixed_2(&cookie, &chhash) + || !PACKET_get_length_prefixed_1(&cookie, &appcookie) + || PACKET_remaining(&cookie) != SHA256_DIGEST_LENGTH) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH); + return 0; + } + + /* We tolerate a cookie age of up to 10 minutes (= 60 * 10 seconds) */ + now = time(NULL); + if (tm > now || (now - tm) > 600) { + /* Cookie is stale. Ignore it */ + return 1; + } + + /* Verify the app cookie */ + if (sctx->verify_stateless_cookie_cb(SSL_CONNECTION_GET_USER_SSL(s), + PACKET_data(&appcookie), + PACKET_remaining(&appcookie)) == 0) { + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_COOKIE_MISMATCH); + return 0; + } + + /* + * Reconstruct the HRR that we would have sent in response to the original + * ClientHello so we can add it to the transcript hash. + * Note: This won't work with custom HRR extensions + */ + if (!WPACKET_init_static_len(&hrrpkt, hrr, sizeof(hrr), 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + if (!WPACKET_put_bytes_u8(&hrrpkt, SSL3_MT_SERVER_HELLO) + || !WPACKET_start_sub_packet_u24(&hrrpkt) + || !WPACKET_put_bytes_u16(&hrrpkt, TLS1_2_VERSION) + || !WPACKET_memcpy(&hrrpkt, hrrrandom, SSL3_RANDOM_SIZE) + || !WPACKET_sub_memcpy_u8(&hrrpkt, s->tmp_session_id, + s->tmp_session_id_len) + || !ssl->method->put_cipher_by_char(s->s3.tmp.new_cipher, &hrrpkt, + &ciphlen) + || !WPACKET_put_bytes_u8(&hrrpkt, 0) + || !WPACKET_start_sub_packet_u16(&hrrpkt)) { + WPACKET_cleanup(&hrrpkt); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + if (!WPACKET_put_bytes_u16(&hrrpkt, TLSEXT_TYPE_supported_versions) + || !WPACKET_start_sub_packet_u16(&hrrpkt) + || !WPACKET_put_bytes_u16(&hrrpkt, s->version) + || !WPACKET_close(&hrrpkt)) { + WPACKET_cleanup(&hrrpkt); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + if (key_share) { + if (!WPACKET_put_bytes_u16(&hrrpkt, TLSEXT_TYPE_key_share) + || !WPACKET_start_sub_packet_u16(&hrrpkt) + || !WPACKET_put_bytes_u16(&hrrpkt, s->s3.group_id) + || !WPACKET_close(&hrrpkt)) { + WPACKET_cleanup(&hrrpkt); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + } + if (!WPACKET_put_bytes_u16(&hrrpkt, TLSEXT_TYPE_cookie) + || !WPACKET_start_sub_packet_u16(&hrrpkt) + || !WPACKET_sub_memcpy_u16(&hrrpkt, data, rawlen) + || !WPACKET_close(&hrrpkt) /* cookie extension */ + || !WPACKET_close(&hrrpkt) /* extension block */ + || !WPACKET_close(&hrrpkt) /* message */ + || !WPACKET_get_total_written(&hrrpkt, &hrrlen) + || !WPACKET_finish(&hrrpkt)) { + WPACKET_cleanup(&hrrpkt); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + + /* Reconstruct the transcript hash */ + if (!create_synthetic_message_hash(s, PACKET_data(&chhash), + PACKET_remaining(&chhash), hrr, + hrrlen)) { + /* SSLfatal() already called */ + return 0; + } + + /* Act as if this ClientHello came after a HelloRetryRequest */ + s->hello_retry_request = SSL_HRR_PENDING; + + s->ext.cookieok = 1; +#endif + + return 1; +} + +int tls_parse_ctos_supported_groups(SSL_CONNECTION *s, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + PACKET supported_groups_list; + + /* Each group is 2 bytes and we must have at least 1. */ + if (!PACKET_as_length_prefixed_2(pkt, &supported_groups_list) + || PACKET_remaining(&supported_groups_list) == 0 + || (PACKET_remaining(&supported_groups_list) % 2) != 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (!s->hit || SSL_CONNECTION_IS_TLS13(s)) { + OPENSSL_free(s->ext.peer_supportedgroups); + s->ext.peer_supportedgroups = NULL; + s->ext.peer_supportedgroups_len = 0; + if (!tls1_save_u16(&supported_groups_list, + &s->ext.peer_supportedgroups, + &s->ext.peer_supportedgroups_len)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + } + + return 1; +} + +int tls_parse_ctos_ems(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ + /* The extension must always be empty */ + if (PACKET_remaining(pkt) != 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (s->options & SSL_OP_NO_EXTENDED_MASTER_SECRET) + return 1; + + s->s3.flags |= TLS1_FLAGS_RECEIVED_EXTMS; + + return 1; +} + + +int tls_parse_ctos_early_data(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ + if (PACKET_remaining(pkt) != 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (s->hello_retry_request != SSL_HRR_NONE) { + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_EXTENSION); + return 0; + } + + return 1; +} + +static SSL_TICKET_STATUS tls_get_stateful_ticket(SSL_CONNECTION *s, PACKET *tick, + SSL_SESSION **sess) +{ + SSL_SESSION *tmpsess = NULL; + + s->ext.ticket_expected = 1; + + switch (PACKET_remaining(tick)) { + case 0: + return SSL_TICKET_EMPTY; + + case SSL_MAX_SSL_SESSION_ID_LENGTH: + break; + + default: + return SSL_TICKET_NO_DECRYPT; + } + + tmpsess = lookup_sess_in_cache(s, PACKET_data(tick), + SSL_MAX_SSL_SESSION_ID_LENGTH); + + if (tmpsess == NULL) + return SSL_TICKET_NO_DECRYPT; + + *sess = tmpsess; + return SSL_TICKET_SUCCESS; +} + +int tls_parse_ctos_psk(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ + PACKET identities, binders, binder; + size_t binderoffset; + int hashsize; + SSL_SESSION *sess = NULL; + unsigned int id, i, ext = 0; + const EVP_MD *md = NULL; + SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); + SSL *ussl = SSL_CONNECTION_GET_USER_SSL(s); + + /* + * If we have no PSK kex mode that we recognise then we can't resume so + * ignore this extension + */ + if ((s->ext.psk_kex_mode + & (TLSEXT_KEX_MODE_FLAG_KE | TLSEXT_KEX_MODE_FLAG_KE_DHE)) == 0) + return 1; + + if (!PACKET_get_length_prefixed_2(pkt, &identities)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + s->ext.ticket_expected = 0; + for (id = 0; PACKET_remaining(&identities) != 0; id++) { + PACKET identity; + unsigned long ticket_agel; + size_t idlen; + + if (!PACKET_get_length_prefixed_2(&identities, &identity) + || !PACKET_get_net_4(&identities, &ticket_agel)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + idlen = PACKET_remaining(&identity); + if (s->psk_find_session_cb != NULL + && !s->psk_find_session_cb(ussl, PACKET_data(&identity), idlen, + &sess)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + +#ifndef OPENSSL_NO_PSK + if (sess == NULL + && s->psk_server_callback != NULL + && idlen <= PSK_MAX_IDENTITY_LEN) { + char *pskid = NULL; + unsigned char pskdata[PSK_MAX_PSK_LEN]; + unsigned int pskdatalen; + + if (!PACKET_strndup(&identity, &pskid)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + pskdatalen = s->psk_server_callback(ussl, pskid, pskdata, + sizeof(pskdata)); + OPENSSL_free(pskid); + if (pskdatalen > PSK_MAX_PSK_LEN) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } else if (pskdatalen > 0) { + const SSL_CIPHER *cipher; + const unsigned char tls13_aes128gcmsha256_id[] = { 0x13, 0x01 }; + + /* + * We found a PSK using an old style callback. We don't know + * the digest so we default to SHA256 as per the TLSv1.3 spec + */ + cipher = SSL_CIPHER_find(SSL_CONNECTION_GET_SSL(s), + tls13_aes128gcmsha256_id); + if (cipher == NULL) { + OPENSSL_cleanse(pskdata, pskdatalen); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + + sess = SSL_SESSION_new(); + if (sess == NULL + || !SSL_SESSION_set1_master_key(sess, pskdata, + pskdatalen) + || !SSL_SESSION_set_cipher(sess, cipher) + || !SSL_SESSION_set_protocol_version(sess, + TLS1_3_VERSION)) { + OPENSSL_cleanse(pskdata, pskdatalen); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + goto err; + } + OPENSSL_cleanse(pskdata, pskdatalen); + } + } +#endif /* OPENSSL_NO_PSK */ + + if (sess != NULL) { + /* We found a PSK */ + SSL_SESSION *sesstmp = ssl_session_dup(sess, 0); + + if (sesstmp == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + goto err; + } + SSL_SESSION_free(sess); + sess = sesstmp; + + /* + * We've just been told to use this session for this context so + * make sure the sid_ctx matches up. + */ + memcpy(sess->sid_ctx, s->sid_ctx, s->sid_ctx_length); + sess->sid_ctx_length = s->sid_ctx_length; + ext = 1; + if (id == 0) + s->ext.early_data_ok = 1; + s->ext.ticket_expected = 1; + } else { + OSSL_TIME t, age, expire; + int ret; + + /* + * If we are using anti-replay protection then we behave as if + * SSL_OP_NO_TICKET is set - we are caching tickets anyway so there + * is no point in using full stateless tickets. + */ + if ((s->options & SSL_OP_NO_TICKET) != 0 + || (s->max_early_data > 0 + && (s->options & SSL_OP_NO_ANTI_REPLAY) == 0)) + ret = tls_get_stateful_ticket(s, &identity, &sess); + else + ret = tls_decrypt_ticket(s, PACKET_data(&identity), + PACKET_remaining(&identity), NULL, 0, + &sess); + + if (ret == SSL_TICKET_EMPTY) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if (ret == SSL_TICKET_FATAL_ERR_MALLOC + || ret == SSL_TICKET_FATAL_ERR_OTHER) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return 0; + } + if (ret == SSL_TICKET_NONE || ret == SSL_TICKET_NO_DECRYPT) + continue; + + /* Check for replay */ + if (s->max_early_data > 0 + && (s->options & SSL_OP_NO_ANTI_REPLAY) == 0 + && !SSL_CTX_remove_session(s->session_ctx, sess)) { + SSL_SESSION_free(sess); + sess = NULL; + continue; + } + + age = ossl_time_subtract(ossl_ms2time(ticket_agel), + ossl_ms2time(sess->ext.tick_age_add)); + t = ossl_time_subtract(ossl_time_now(), sess->time); + + /* + * Although internally we use OSS_TIME which has ns granularity, + * when SSL_SESSION structures are serialised/deserialised we use + * second granularity for the sess->time field. Therefore it could + * appear that the client's ticket age is longer than ours (our + * ticket age calculation should always be slightly longer than the + * client's due to the network latency). Therefore we add 1000ms to + * our age calculation to adjust for rounding errors. + */ + expire = ossl_time_add(t, ossl_ms2time(1000)); + + if (id == 0 + && ossl_time_compare(sess->timeout, t) >= 0 + && ossl_time_compare(age, expire) <= 0 + && ossl_time_compare(ossl_time_add(age, TICKET_AGE_ALLOWANCE), + expire) >= 0) { + /* + * Ticket age is within tolerance and not expired. We allow it + * for early data + */ + s->ext.early_data_ok = 1; + } + } + + md = ssl_md(sctx, sess->cipher->algorithm2); + if (md == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + goto err; + } + if (!EVP_MD_is_a(md, + EVP_MD_get0_name(ssl_md(sctx, + s->s3.tmp.new_cipher->algorithm2)))) { + /* The ciphersuite is not compatible with this session. */ + SSL_SESSION_free(sess); + sess = NULL; + s->ext.early_data_ok = 0; + s->ext.ticket_expected = 0; + continue; + } + break; + } + + if (sess == NULL) + return 1; + + binderoffset = PACKET_data(pkt) - (const unsigned char *)s->init_buf->data; + hashsize = EVP_MD_get_size(md); + if (hashsize <= 0) + goto err; + + if (!PACKET_get_length_prefixed_2(pkt, &binders)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + goto err; + } + + for (i = 0; i <= id; i++) { + if (!PACKET_get_length_prefixed_1(&binders, &binder)) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + goto err; + } + } + + if (PACKET_remaining(&binder) != (size_t)hashsize) { + SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + goto err; + } + if (tls_psk_do_binder(s, md, (const unsigned char *)s->init_buf->data, + binderoffset, PACKET_data(&binder), NULL, sess, 0, + ext) != 1) { + /* SSLfatal() already called */ + goto err; + } + + s->ext.tick_identity = id; + + SSL_SESSION_free(s->session); + s->session = sess; + return 1; +err: + SSL_SESSION_free(sess); + return 0; +} + +int tls_parse_ctos_post_handshake_auth(SSL_CONNECTION *s, PACKET *pkt, + ossl_unused unsigned int context, + ossl_unused X509 *x, + ossl_unused size_t chainidx) +{ + if (PACKET_remaining(pkt) != 0) { + SSLfatal(s, SSL_AD_DECODE_ERROR, + SSL_R_POST_HANDSHAKE_AUTH_ENCODING_ERR); + return 0; + } + + s->post_handshake_auth = SSL_PHA_EXT_RECEIVED; + + return 1; +} + +/* + * Add the server's renegotiation binding + */ +EXT_RETURN tls_construct_stoc_renegotiate(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + if (!s->s3.send_connection_binding) + return EXT_RETURN_NOT_SENT; + + /* Still add this even if SSL_OP_NO_RENEGOTIATION is set */ + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_renegotiate) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_start_sub_packet_u8(pkt) + || !WPACKET_memcpy(pkt, s->s3.previous_client_finished, + s->s3.previous_client_finished_len) + || !WPACKET_memcpy(pkt, s->s3.previous_server_finished, + s->s3.previous_server_finished_len) + || !WPACKET_close(pkt) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_server_name(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + if (s->servername_done != 1) + return EXT_RETURN_NOT_SENT; + + /* + * Prior to TLSv1.3 we ignore any SNI in the current handshake if resuming. + * We just use the servername from the initial handshake. + */ + if (s->hit && !SSL_CONNECTION_IS_TLS13(s)) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_server_name) + || !WPACKET_put_bytes_u16(pkt, 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +/* Add/include the server's max fragment len extension into ServerHello */ +EXT_RETURN tls_construct_stoc_maxfragmentlen(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + if (!USE_MAX_FRAGMENT_LENGTH_EXT(s->session)) + return EXT_RETURN_NOT_SENT; + + /*- + * 4 bytes for this extension type and extension length + * 1 byte for the Max Fragment Length code value. + */ + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_max_fragment_length) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u8(pkt, s->session->ext.max_fragment_len_mode) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_ec_pt_formats(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + unsigned long alg_k = s->s3.tmp.new_cipher->algorithm_mkey; + unsigned long alg_a = s->s3.tmp.new_cipher->algorithm_auth; + int using_ecc = ((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA)) + && (s->ext.peer_ecpointformats != NULL); + const unsigned char *plist; + size_t plistlen; + + if (!using_ecc) + return EXT_RETURN_NOT_SENT; + + tls1_get_formatlist(s, &plist, &plistlen); + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_ec_point_formats) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_sub_memcpy_u8(pkt, plist, plistlen) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_supported_groups(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + const uint16_t *groups; + size_t numgroups, i, first = 1; + int version; + + /* s->s3.group_id is non zero if we accepted a key_share */ + if (s->s3.group_id == 0) + return EXT_RETURN_NOT_SENT; + + /* Get our list of supported groups */ + tls1_get_supported_groups(s, &groups, &numgroups); + if (numgroups == 0) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + /* Copy group ID if supported */ + version = SSL_version(SSL_CONNECTION_GET_SSL(s)); + for (i = 0; i < numgroups; i++) { + uint16_t group = groups[i]; + + if (tls_valid_group(s, group, version, version, 0, NULL) + && tls_group_allowed(s, group, SSL_SECOP_CURVE_SUPPORTED)) { + if (first) { + /* + * Check if the client is already using our preferred group. If + * so we don't need to add this extension + */ + if (s->s3.group_id == group) + return EXT_RETURN_NOT_SENT; + + /* Add extension header */ + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_groups) + /* Sub-packet for supported_groups extension */ + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_start_sub_packet_u16(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + first = 0; + } + if (!WPACKET_put_bytes_u16(pkt, group)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + } + } + + if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_session_ticket(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + if (!s->ext.ticket_expected || !tls_use_ticket(s)) { + s->ext.ticket_expected = 0; + return EXT_RETURN_NOT_SENT; + } + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_session_ticket) + || !WPACKET_put_bytes_u16(pkt, 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +#ifndef OPENSSL_NO_OCSP +EXT_RETURN tls_construct_stoc_status_request(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + /* We don't currently support this extension inside a CertificateRequest */ + if (context == SSL_EXT_TLS1_3_CERTIFICATE_REQUEST) + return EXT_RETURN_NOT_SENT; + + if (!s->ext.status_expected) + return EXT_RETURN_NOT_SENT; + + if (SSL_CONNECTION_IS_TLS13(s) && chainidx != 0) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_status_request) + || !WPACKET_start_sub_packet_u16(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + /* + * In TLSv1.3 we include the certificate status itself. In <= TLSv1.2 we + * send back an empty extension, with the certificate status appearing as a + * separate message + */ + if (SSL_CONNECTION_IS_TLS13(s) && !tls_construct_cert_status_body(s, pkt)) { + /* SSLfatal() already called */ + return EXT_RETURN_FAIL; + } + if (!WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} +#endif + +#ifndef OPENSSL_NO_NEXTPROTONEG +EXT_RETURN tls_construct_stoc_next_proto_neg(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + const unsigned char *npa; + unsigned int npalen; + int ret; + int npn_seen = s->s3.npn_seen; + SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); + + s->s3.npn_seen = 0; + if (!npn_seen || sctx->ext.npn_advertised_cb == NULL) + return EXT_RETURN_NOT_SENT; + + ret = sctx->ext.npn_advertised_cb(SSL_CONNECTION_GET_USER_SSL(s), &npa, + &npalen, sctx->ext.npn_advertised_cb_arg); + if (ret == SSL_TLSEXT_ERR_OK) { + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_next_proto_neg) + || !WPACKET_sub_memcpy_u16(pkt, npa, npalen)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + s->s3.npn_seen = 1; + return EXT_RETURN_SENT; + } + + return EXT_RETURN_NOT_SENT; +} +#endif + +EXT_RETURN tls_construct_stoc_alpn(SSL_CONNECTION *s, WPACKET *pkt, unsigned int context, + X509 *x, size_t chainidx) +{ + if (s->s3.alpn_selected == NULL) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, + TLSEXT_TYPE_application_layer_protocol_negotiation) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_sub_memcpy_u8(pkt, s->s3.alpn_selected, + s->s3.alpn_selected_len) + || !WPACKET_close(pkt) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +#ifndef OPENSSL_NO_SRTP +EXT_RETURN tls_construct_stoc_use_srtp(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + if (s->srtp_profile == NULL) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_use_srtp) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u16(pkt, 2) + || !WPACKET_put_bytes_u16(pkt, s->srtp_profile->id) + || !WPACKET_put_bytes_u8(pkt, 0) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} +#endif + +EXT_RETURN tls_construct_stoc_etm(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + if (!s->ext.use_etm) + return EXT_RETURN_NOT_SENT; + + /* + * Don't use encrypt_then_mac if AEAD or RC4 might want to disable + * for other cases too. + */ + if (s->s3.tmp.new_cipher->algorithm_mac == SSL_AEAD + || s->s3.tmp.new_cipher->algorithm_enc == SSL_RC4 + || s->s3.tmp.new_cipher->algorithm_enc == SSL_eGOST2814789CNT + || s->s3.tmp.new_cipher->algorithm_enc == SSL_eGOST2814789CNT12 + || s->s3.tmp.new_cipher->algorithm_enc == SSL_MAGMA + || s->s3.tmp.new_cipher->algorithm_enc == SSL_KUZNYECHIK) { + s->ext.use_etm = 0; + return EXT_RETURN_NOT_SENT; + } + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_encrypt_then_mac) + || !WPACKET_put_bytes_u16(pkt, 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_ems(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + if ((s->s3.flags & TLS1_FLAGS_RECEIVED_EXTMS) == 0) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_extended_master_secret) + || !WPACKET_put_bytes_u16(pkt, 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_supported_versions(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + if (!ossl_assert(SSL_CONNECTION_IS_TLS13(s))) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_versions) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u16(pkt, s->version) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_key_share(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ +#ifndef OPENSSL_NO_TLS1_3 + unsigned char *encoded_pubkey; + size_t encoded_pubkey_len = 0; + EVP_PKEY *ckey = s->s3.peer_tmp, *skey = NULL; + const TLS_GROUP_INFO *ginf = NULL; + + if (s->hello_retry_request == SSL_HRR_PENDING) { + if (ckey != NULL) { + /* Original key_share was acceptable so don't ask for another one */ + return EXT_RETURN_NOT_SENT; + } + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_key_share) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u16(pkt, s->s3.group_id) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; + } + + if (ckey == NULL) { + /* No key_share received from client - must be resuming */ + if (!s->hit || !tls13_generate_handshake_secret(s, NULL, 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + return EXT_RETURN_NOT_SENT; + } + + if (s->hit && (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE) == 0) { + /* + * PSK ('hit') and explicitly not doing DHE. If the client sent the + * DHE option, we take it by default, except if non-DHE would be + * preferred by config, but this case would have been handled in + * tls_parse_ctos_psk_kex_modes(). + */ + return EXT_RETURN_NOT_SENT; + } + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_key_share) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u16(pkt, s->s3.group_id)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + if ((ginf = tls1_group_id_lookup(SSL_CONNECTION_GET_CTX(s), + s->s3.group_id)) == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + if (!ginf->is_kem) { + /* Regular KEX */ + skey = ssl_generate_pkey(s, ckey); + if (skey == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SSL_LIB); + return EXT_RETURN_FAIL; + } + + /* Generate encoding of server key */ + encoded_pubkey_len = EVP_PKEY_get1_encoded_public_key(skey, &encoded_pubkey); + if (encoded_pubkey_len == 0) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EC_LIB); + EVP_PKEY_free(skey); + return EXT_RETURN_FAIL; + } + + if (!WPACKET_sub_memcpy_u16(pkt, encoded_pubkey, encoded_pubkey_len) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + EVP_PKEY_free(skey); + OPENSSL_free(encoded_pubkey); + return EXT_RETURN_FAIL; + } + OPENSSL_free(encoded_pubkey); + + /* + * This causes the crypto state to be updated based on the derived keys + */ + s->s3.tmp.pkey = skey; + if (ssl_derive(s, skey, ckey, 1) == 0) { + /* SSLfatal() already called */ + return EXT_RETURN_FAIL; + } + } else { + /* KEM mode */ + unsigned char *ct = NULL; + size_t ctlen = 0; + + /* + * This does not update the crypto state. + * + * The generated pms is stored in `s->s3.tmp.pms` to be later used via + * ssl_gensecret(). + */ + if (ssl_encapsulate(s, ckey, &ct, &ctlen, 0) == 0) { + /* SSLfatal() already called */ + return EXT_RETURN_FAIL; + } + + if (ctlen == 0) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + OPENSSL_free(ct); + return EXT_RETURN_FAIL; + } + + if (!WPACKET_sub_memcpy_u16(pkt, ct, ctlen) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + OPENSSL_free(ct); + return EXT_RETURN_FAIL; + } + OPENSSL_free(ct); + + /* + * This causes the crypto state to be updated based on the generated pms + */ + if (ssl_gensecret(s, s->s3.tmp.pms, s->s3.tmp.pmslen) == 0) { + /* SSLfatal() already called */ + return EXT_RETURN_FAIL; + } + } + s->s3.did_kex = 1; + return EXT_RETURN_SENT; +#else + return EXT_RETURN_FAIL; +#endif +} + +EXT_RETURN tls_construct_stoc_cookie(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ +#ifndef OPENSSL_NO_TLS1_3 + unsigned char *hashval1, *hashval2, *appcookie1, *appcookie2, *cookie; + unsigned char *hmac, *hmac2; + size_t startlen, ciphlen, totcookielen, hashlen, hmaclen, appcookielen; + EVP_MD_CTX *hctx; + EVP_PKEY *pkey; + int ret = EXT_RETURN_FAIL; + SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); + SSL *ssl = SSL_CONNECTION_GET_SSL(s); + SSL *ussl = SSL_CONNECTION_GET_USER_SSL(s); + + if ((s->s3.flags & TLS1_FLAGS_STATELESS) == 0) + return EXT_RETURN_NOT_SENT; + + if (sctx->gen_stateless_cookie_cb == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_COOKIE_CALLBACK_SET); + return EXT_RETURN_FAIL; + } + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_cookie) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_get_total_written(pkt, &startlen) + || !WPACKET_reserve_bytes(pkt, MAX_COOKIE_SIZE, &cookie) + || !WPACKET_put_bytes_u16(pkt, COOKIE_STATE_FORMAT_VERSION) + || !WPACKET_put_bytes_u16(pkt, TLS1_3_VERSION) + || !WPACKET_put_bytes_u16(pkt, s->s3.group_id) + || !ssl->method->put_cipher_by_char(s->s3.tmp.new_cipher, pkt, + &ciphlen) + /* Is there a key_share extension present in this HRR? */ + || !WPACKET_put_bytes_u8(pkt, s->s3.peer_tmp == NULL) + || !WPACKET_put_bytes_u64(pkt, time(NULL)) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_reserve_bytes(pkt, EVP_MAX_MD_SIZE, &hashval1)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + /* + * Get the hash of the initial ClientHello. ssl_handshake_hash() operates + * on raw buffers, so we first reserve sufficient bytes (above) and then + * subsequently allocate them (below) + */ + if (!ssl3_digest_cached_records(s, 0) + || !ssl_handshake_hash(s, hashval1, EVP_MAX_MD_SIZE, &hashlen)) { + /* SSLfatal() already called */ + return EXT_RETURN_FAIL; + } + + if (!WPACKET_allocate_bytes(pkt, hashlen, &hashval2) + || !ossl_assert(hashval1 == hashval2) + || !WPACKET_close(pkt) + || !WPACKET_start_sub_packet_u8(pkt) + || !WPACKET_reserve_bytes(pkt, SSL_COOKIE_LENGTH, &appcookie1)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + /* Generate the application cookie */ + if (sctx->gen_stateless_cookie_cb(ussl, appcookie1, + &appcookielen) == 0) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COOKIE_GEN_CALLBACK_FAILURE); + return EXT_RETURN_FAIL; + } + + if (!WPACKET_allocate_bytes(pkt, appcookielen, &appcookie2) + || !ossl_assert(appcookie1 == appcookie2) + || !WPACKET_close(pkt) + || !WPACKET_get_total_written(pkt, &totcookielen) + || !WPACKET_reserve_bytes(pkt, SHA256_DIGEST_LENGTH, &hmac)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + hmaclen = SHA256_DIGEST_LENGTH; + + totcookielen -= startlen; + if (!ossl_assert(totcookielen <= MAX_COOKIE_SIZE - SHA256_DIGEST_LENGTH)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + /* HMAC the cookie */ + hctx = EVP_MD_CTX_create(); + pkey = EVP_PKEY_new_raw_private_key_ex(sctx->libctx, "HMAC", + sctx->propq, + s->session_ctx->ext.cookie_hmac_key, + sizeof(s->session_ctx->ext.cookie_hmac_key)); + if (hctx == NULL || pkey == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); + goto err; + } + + if (EVP_DigestSignInit_ex(hctx, NULL, "SHA2-256", sctx->libctx, + sctx->propq, pkey, NULL) <= 0 + || EVP_DigestSign(hctx, hmac, &hmaclen, cookie, + totcookielen) <= 0) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + goto err; + } + + if (!ossl_assert(totcookielen + hmaclen <= MAX_COOKIE_SIZE)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + goto err; + } + + if (!WPACKET_allocate_bytes(pkt, hmaclen, &hmac2) + || !ossl_assert(hmac == hmac2) + || !ossl_assert(cookie == hmac - totcookielen) + || !WPACKET_close(pkt) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + goto err; + } + + ret = EXT_RETURN_SENT; + + err: + EVP_MD_CTX_free(hctx); + EVP_PKEY_free(pkey); + return ret; +#else + return EXT_RETURN_FAIL; +#endif +} + +EXT_RETURN tls_construct_stoc_cryptopro_bug(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + const unsigned char cryptopro_ext[36] = { + 0xfd, 0xe8, /* 65000 */ + 0x00, 0x20, /* 32 bytes length */ + 0x30, 0x1e, 0x30, 0x08, 0x06, 0x06, 0x2a, 0x85, + 0x03, 0x02, 0x02, 0x09, 0x30, 0x08, 0x06, 0x06, + 0x2a, 0x85, 0x03, 0x02, 0x02, 0x16, 0x30, 0x08, + 0x06, 0x06, 0x2a, 0x85, 0x03, 0x02, 0x02, 0x17 + }; + + if (((s->s3.tmp.new_cipher->id & 0xFFFF) != 0x80 + && (s->s3.tmp.new_cipher->id & 0xFFFF) != 0x81) + || (SSL_get_options(SSL_CONNECTION_GET_SSL(s)) + & SSL_OP_CRYPTOPRO_TLSEXT_BUG) == 0) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_memcpy(pkt, cryptopro_ext, sizeof(cryptopro_ext))) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_early_data(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx) +{ + if (context == SSL_EXT_TLS1_3_NEW_SESSION_TICKET) { + if (s->max_early_data == 0) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_early_data) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u32(pkt, s->max_early_data) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; + } + + if (s->ext.early_data != SSL_EARLY_DATA_ACCEPTED) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_early_data) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_psk(SSL_CONNECTION *s, WPACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + if (!s->hit) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u16(pkt, s->ext.tick_identity) + || !WPACKET_close(pkt)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} + +EXT_RETURN tls_construct_stoc_client_cert_type(SSL_CONNECTION *sc, WPACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + if (sc->ext.client_cert_type_ctos == OSSL_CERT_TYPE_CTOS_ERROR + && (send_certificate_request(sc) + || sc->post_handshake_auth == SSL_PHA_EXT_RECEIVED)) { + /* Did not receive an acceptable cert type - and doing client auth */ + SSLfatal(sc, SSL_AD_UNSUPPORTED_CERTIFICATE, SSL_R_BAD_EXTENSION); + return EXT_RETURN_FAIL; + } + + if (sc->ext.client_cert_type == TLSEXT_cert_type_x509) { + sc->ext.client_cert_type_ctos = OSSL_CERT_TYPE_CTOS_NONE; + return EXT_RETURN_NOT_SENT; + } + + /* + * Note: only supposed to send this if we are going to do a cert request, + * but TLSv1.3 could do a PHA request if the client supports it + */ + if ((!send_certificate_request(sc) && sc->post_handshake_auth != SSL_PHA_EXT_RECEIVED) + || sc->ext.client_cert_type_ctos != OSSL_CERT_TYPE_CTOS_GOOD + || sc->client_cert_type == NULL) { + /* if we don't send it, reset to TLSEXT_cert_type_x509 */ + sc->ext.client_cert_type_ctos = OSSL_CERT_TYPE_CTOS_NONE; + sc->ext.client_cert_type = TLSEXT_cert_type_x509; + return EXT_RETURN_NOT_SENT; + } + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_client_cert_type) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u8(pkt, sc->ext.client_cert_type) + || !WPACKET_close(pkt)) { + SSLfatal(sc, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + return EXT_RETURN_SENT; +} + +/* One of |pref|, |other| is configured and the values are sanitized */ +static int reconcile_cert_type(const unsigned char *pref, size_t pref_len, + const unsigned char *other, size_t other_len, + uint8_t *chosen_cert_type) +{ + size_t i; + + for (i = 0; i < pref_len; i++) { + if (memchr(other, pref[i], other_len) != NULL) { + *chosen_cert_type = pref[i]; + return OSSL_CERT_TYPE_CTOS_GOOD; + } + } + return OSSL_CERT_TYPE_CTOS_ERROR; +} + +int tls_parse_ctos_client_cert_type(SSL_CONNECTION *sc, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + PACKET supported_cert_types; + const unsigned char *data; + size_t len; + + /* Ignore the extension */ + if (sc->client_cert_type == NULL) { + sc->ext.client_cert_type_ctos = OSSL_CERT_TYPE_CTOS_NONE; + sc->ext.client_cert_type = TLSEXT_cert_type_x509; + return 1; + } + + if (!PACKET_as_length_prefixed_1(pkt, &supported_cert_types)) { + sc->ext.client_cert_type_ctos = OSSL_CERT_TYPE_CTOS_ERROR; + SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + if ((len = PACKET_remaining(&supported_cert_types)) == 0) { + sc->ext.client_cert_type_ctos = OSSL_CERT_TYPE_CTOS_ERROR; + SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + if (!PACKET_get_bytes(&supported_cert_types, &data, len)) { + sc->ext.client_cert_type_ctos = OSSL_CERT_TYPE_CTOS_ERROR; + SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + /* client_cert_type: client (peer) has priority */ + sc->ext.client_cert_type_ctos = reconcile_cert_type(data, len, + sc->client_cert_type, sc->client_cert_type_len, + &sc->ext.client_cert_type); + + /* Ignore the error until sending - so we can check cert auth*/ + return 1; +} + +EXT_RETURN tls_construct_stoc_server_cert_type(SSL_CONNECTION *sc, WPACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + if (sc->ext.server_cert_type == TLSEXT_cert_type_x509) { + sc->ext.server_cert_type_ctos = OSSL_CERT_TYPE_CTOS_NONE; + return EXT_RETURN_NOT_SENT; + } + if (sc->ext.server_cert_type_ctos != OSSL_CERT_TYPE_CTOS_GOOD + || sc->server_cert_type == NULL) { + /* if we don't send it, reset to TLSEXT_cert_type_x509 */ + sc->ext.server_cert_type_ctos = OSSL_CERT_TYPE_CTOS_NONE; + sc->ext.server_cert_type = TLSEXT_cert_type_x509; + return EXT_RETURN_NOT_SENT; + } + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_server_cert_type) + || !WPACKET_start_sub_packet_u16(pkt) + || !WPACKET_put_bytes_u8(pkt, sc->ext.server_cert_type) + || !WPACKET_close(pkt)) { + SSLfatal(sc, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + return EXT_RETURN_SENT; +} + +int tls_parse_ctos_server_cert_type(SSL_CONNECTION *sc, PACKET *pkt, + unsigned int context, + X509 *x, size_t chainidx) +{ + PACKET supported_cert_types; + const unsigned char *data; + size_t len; + + /* Ignore the extension */ + if (sc->server_cert_type == NULL) { + sc->ext.server_cert_type_ctos = OSSL_CERT_TYPE_CTOS_NONE; + sc->ext.server_cert_type = TLSEXT_cert_type_x509; + return 1; + } + + if (!PACKET_as_length_prefixed_1(pkt, &supported_cert_types)) { + SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + + if ((len = PACKET_remaining(&supported_cert_types)) == 0) { + SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + if (!PACKET_get_bytes(&supported_cert_types, &data, len)) { + SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); + return 0; + } + /* server_cert_type: server (this) has priority */ + sc->ext.server_cert_type_ctos = reconcile_cert_type(sc->server_cert_type, sc->server_cert_type_len, + data, len, + &sc->ext.server_cert_type); + if (sc->ext.server_cert_type_ctos == OSSL_CERT_TYPE_CTOS_GOOD) + return 1; + + /* Did not receive an acceptable cert type */ + SSLfatal(sc, SSL_AD_UNSUPPORTED_CERTIFICATE, SSL_R_BAD_EXTENSION); + return 0; +} |