static enum ssl_hs_wait_t do_process_second_client_hello(SSL *ssl, SSL_HANDSHAKE *hs) { if (!tls13_check_message_type(ssl, SSL3_MT_CLIENT_HELLO)) { return ssl_hs_error; } struct ssl_early_callback_ctx client_hello; if (!ssl_early_callback_init(ssl, &client_hello, ssl->init_msg, ssl->init_num)) { OPENSSL_PUT_ERROR(SSL, SSL_R_CLIENTHELLO_PARSE_FAILED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return ssl_hs_error; } int need_retry; if (!resolve_ecdhe_secret(ssl, &need_retry, &client_hello)) { if (need_retry) { /* Only send one HelloRetryRequest. */ ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE); } return ssl_hs_error; } if (!ssl->method->hash_current_message(ssl)) { return ssl_hs_error; } ssl->method->received_flight(ssl); hs->state = state_send_server_hello; return ssl_hs_ok; }
static enum ssl_hs_wait_t do_select_parameters(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; /* The short record header extension is incompatible with early data. */ if (ssl->s3->skip_early_data && ssl->s3->short_header) { OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION); return ssl_hs_error; } SSL_CLIENT_HELLO client_hello; if (!ssl_client_hello_init(ssl, &client_hello, ssl->init_msg, ssl->init_num)) { OPENSSL_PUT_ERROR(SSL, SSL_R_CLIENTHELLO_PARSE_FAILED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return ssl_hs_error; } /* Negotiate the cipher suite. */ ssl->s3->tmp.new_cipher = choose_tls13_cipher(ssl, &client_hello); if (ssl->s3->tmp.new_cipher == NULL) { OPENSSL_PUT_ERROR(SSL, SSL_R_NO_SHARED_CIPHER); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); return ssl_hs_error; } /* Decode the ticket if we agree on a PSK key exchange mode. */ uint8_t alert = SSL_AD_DECODE_ERROR; SSL_SESSION *session = NULL; CBS pre_shared_key, binders; if (hs->accept_psk_mode && ssl_client_hello_get_extension(&client_hello, &pre_shared_key, TLSEXT_TYPE_pre_shared_key)) { /* Verify that the pre_shared_key extension is the last extension in * ClientHello. */ if (CBS_data(&pre_shared_key) + CBS_len(&pre_shared_key) != client_hello.extensions + client_hello.extensions_len) { OPENSSL_PUT_ERROR(SSL, SSL_R_PRE_SHARED_KEY_MUST_BE_LAST); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return ssl_hs_error; } if (!ssl_ext_pre_shared_key_parse_clienthello(hs, &session, &binders, &alert, &pre_shared_key)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); return ssl_hs_error; } } if (session != NULL && !ssl_session_is_resumable(ssl, session)) { SSL_SESSION_free(session); session = NULL; } /* Set up the new session, either using the original one as a template or * creating a fresh one. */ if (session == NULL) { if (!ssl_get_new_session(hs, 1 /* server */)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } ssl->s3->new_session->cipher = ssl->s3->tmp.new_cipher; /* On new sessions, stash the SNI value in the session. */ if (hs->hostname != NULL) { OPENSSL_free(ssl->s3->new_session->tlsext_hostname); ssl->s3->new_session->tlsext_hostname = BUF_strdup(hs->hostname); if (ssl->s3->new_session->tlsext_hostname == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } } } else { /* Check the PSK binder. */ if (!tls13_verify_psk_binder(ssl, session, &binders)) { SSL_SESSION_free(session); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR); return ssl_hs_error; } /* Only authentication information carries over in TLS 1.3. */ ssl->s3->new_session = SSL_SESSION_dup(session, SSL_SESSION_DUP_AUTH_ONLY); if (ssl->s3->new_session == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } ssl->s3->session_reused = 1; SSL_SESSION_free(session); /* Resumption incorporates fresh key material, so refresh the timeout. */ ssl_session_renew_timeout(ssl, ssl->s3->new_session, ssl->initial_ctx->session_psk_dhe_timeout); } if (ssl->ctx->dos_protection_cb != NULL && ssl->ctx->dos_protection_cb(&client_hello) == 0) { /* Connection rejected for DOS reasons. */ OPENSSL_PUT_ERROR(SSL, SSL_R_CONNECTION_REJECTED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } /* HTTP/2 negotiation depends on the cipher suite, so ALPN negotiation was * deferred. Complete it now. */ if (!ssl_negotiate_alpn(hs, &alert, &client_hello)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); return ssl_hs_error; } /* The PRF hash is now known. Set up the key schedule and hash the * ClientHello. */ size_t hash_len = EVP_MD_size(ssl_get_handshake_digest(ssl_get_algorithm_prf(ssl))); if (!tls13_init_key_schedule(hs) || !ssl_hash_current_message(ssl)) { return ssl_hs_error; } /* Incorporate the PSK into the running secret. */ if (ssl->s3->session_reused) { if (!tls13_advance_key_schedule(hs, ssl->s3->new_session->master_key, ssl->s3->new_session->master_key_length)) { return ssl_hs_error; } } else if (!tls13_advance_key_schedule(hs, kZeroes, hash_len)) { return ssl_hs_error; } ssl->method->received_flight(ssl); /* Resolve ECDHE and incorporate it into the secret. */ int need_retry; if (!resolve_ecdhe_secret(hs, &need_retry, &client_hello)) { if (need_retry) { hs->tls13_state = state_send_hello_retry_request; return ssl_hs_ok; } return ssl_hs_error; } hs->tls13_state = state_send_server_hello; return ssl_hs_ok; }
static enum ssl_hs_wait_t do_select_parameters(SSL *ssl, SSL_HANDSHAKE *hs) { /* Call |cert_cb| to update server certificates if required. */ if (ssl->cert->cert_cb != NULL) { int rv = ssl->cert->cert_cb(ssl, ssl->cert->cert_cb_arg); if (rv == 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } if (rv < 0) { hs->state = state_select_parameters; return ssl_hs_x509_lookup; } } struct ssl_early_callback_ctx client_hello; if (!ssl_early_callback_init(ssl, &client_hello, ssl->init_msg, ssl->init_num)) { OPENSSL_PUT_ERROR(SSL, SSL_R_CLIENTHELLO_PARSE_FAILED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return ssl_hs_error; } const SSL_CIPHER *cipher = ssl3_choose_cipher(ssl, &client_hello, ssl_get_cipher_preferences(ssl)); if (cipher == NULL) { OPENSSL_PUT_ERROR(SSL, SSL_R_NO_SHARED_CIPHER); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); return ssl_hs_error; } ssl->s3->new_session->cipher = cipher; ssl->s3->tmp.new_cipher = cipher; ssl->method->received_flight(ssl); /* The PRF hash is now known. Set up the key schedule and hash the * ClientHello. */ size_t hash_len = EVP_MD_size(ssl_get_handshake_digest(ssl_get_algorithm_prf(ssl))); if (!tls13_init_key_schedule(ssl, kZeroes, hash_len)) { return ssl_hs_error; } /* Resolve PSK and incorporate it into the secret. */ if (!resolve_psk_secret(ssl)) { return ssl_hs_error; } /* Resolve ECDHE and incorporate it into the secret. */ int need_retry; if (!resolve_ecdhe_secret(ssl, &need_retry, &client_hello)) { if (need_retry) { hs->state = state_send_hello_retry_request; return ssl_hs_ok; } return ssl_hs_error; } hs->state = state_send_server_hello; return ssl_hs_ok; }
static enum ssl_hs_wait_t do_select_session(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; SSL_CLIENT_HELLO client_hello; if (!ssl_client_hello_init(ssl, &client_hello, ssl->init_msg, ssl->init_num)) { OPENSSL_PUT_ERROR(SSL, SSL_R_CLIENTHELLO_PARSE_FAILED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return ssl_hs_error; } uint8_t alert = SSL_AD_DECODE_ERROR; SSL_SESSION *session = NULL; switch (select_session(hs, &alert, &session, &ssl->s3->ticket_age_skew, &client_hello)) { case ssl_ticket_aead_ignore_ticket: assert(session == NULL); if (!ssl_get_new_session(hs, 1 /* server */)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } break; case ssl_ticket_aead_success: /* Carry over authentication information from the previous handshake into * a fresh session. */ hs->new_session = SSL_SESSION_dup(session, SSL_SESSION_DUP_AUTH_ONLY); if (/* Early data must be acceptable for this ticket. */ ssl->cert->enable_early_data && session->ticket_max_early_data != 0 && /* The client must have offered early data. */ hs->early_data_offered && /* Channel ID is incompatible with 0-RTT. */ !ssl->s3->tlsext_channel_id_valid && /* The negotiated ALPN must match the one in the ticket. */ ssl->s3->alpn_selected_len == session->early_alpn_len && OPENSSL_memcmp(ssl->s3->alpn_selected, session->early_alpn, ssl->s3->alpn_selected_len) == 0) { ssl->early_data_accepted = 1; } SSL_SESSION_free(session); if (hs->new_session == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } ssl->s3->session_reused = 1; /* Resumption incorporates fresh key material, so refresh the timeout. */ ssl_session_renew_timeout(ssl, hs->new_session, ssl->session_ctx->session_psk_dhe_timeout); break; case ssl_ticket_aead_error: ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); return ssl_hs_error; case ssl_ticket_aead_retry: hs->tls13_state = state_select_session; return ssl_hs_pending_ticket; } /* Record connection properties in the new session. */ hs->new_session->cipher = hs->new_cipher; if (hs->hostname != NULL) { OPENSSL_free(hs->new_session->tlsext_hostname); hs->new_session->tlsext_hostname = BUF_strdup(hs->hostname); if (hs->new_session->tlsext_hostname == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } } /* Store the initial negotiated ALPN in the session. */ if (ssl->s3->alpn_selected != NULL) { hs->new_session->early_alpn = BUF_memdup(ssl->s3->alpn_selected, ssl->s3->alpn_selected_len); if (hs->new_session->early_alpn == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } hs->new_session->early_alpn_len = ssl->s3->alpn_selected_len; } if (ssl->ctx->dos_protection_cb != NULL && ssl->ctx->dos_protection_cb(&client_hello) == 0) { /* Connection rejected for DOS reasons. */ OPENSSL_PUT_ERROR(SSL, SSL_R_CONNECTION_REJECTED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return ssl_hs_error; } /* Incorporate the PSK into the running secret. */ if (ssl->s3->session_reused) { if (!tls13_advance_key_schedule(hs, hs->new_session->master_key, hs->new_session->master_key_length)) { return ssl_hs_error; } } else if (!tls13_advance_key_schedule(hs, kZeroes, hs->hash_len)) { return ssl_hs_error; } if (ssl->early_data_accepted) { if (!tls13_derive_early_secrets(hs)) { return ssl_hs_error; } } else if (hs->early_data_offered) { ssl->s3->skip_early_data = 1; } ssl->method->received_flight(ssl); /* Resolve ECDHE and incorporate it into the secret. */ int need_retry; if (!resolve_ecdhe_secret(hs, &need_retry, &client_hello)) { if (need_retry) { ssl->early_data_accepted = 0; ssl->s3->skip_early_data = 1; hs->tls13_state = state_send_hello_retry_request; return ssl_hs_ok; } return ssl_hs_error; } hs->tls13_state = state_send_server_hello; return ssl_hs_ok; }