/* * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved. * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved * Copyright 2005 Nokia. All rights reserved. * * Licensed under the OpenSSL license (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 #include "../ssl_locl.h" #include "statem_locl.h" #include "internal/constant_time_locl.h" #include "internal/cryptlib.h" #include #include #include #include #include #include #include #include #include static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt); /* * ossl_statem_server13_read_transition() encapsulates the logic for the allowed * handshake state transitions when a TLSv1.3 server is reading messages from * the client. The message type that the client has sent is provided in |mt|. * The current state is in |s->statem.hand_state|. * * Return values are 1 for success (transition allowed) and 0 on error * (transition not allowed) */ static int ossl_statem_server13_read_transition(SSL *s, int mt) { OSSL_STATEM *st = &s->statem; /* * Note: There is no case for TLS_ST_BEFORE because at that stage we have * not negotiated TLSv1.3 yet, so that case is handled by * ossl_statem_server_read_transition() */ switch (st->hand_state) { default: break; case TLS_ST_EARLY_DATA: if (s->hello_retry_request == SSL_HRR_PENDING) { if (mt == SSL3_MT_CLIENT_HELLO) { st->hand_state = TLS_ST_SR_CLNT_HELLO; return 1; } break; } else if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED) { if (mt == SSL3_MT_END_OF_EARLY_DATA) { st->hand_state = TLS_ST_SR_END_OF_EARLY_DATA; return 1; } break; } /* Fall through */ case TLS_ST_SR_END_OF_EARLY_DATA: case TLS_ST_SW_FINISHED: if (s->s3->tmp.cert_request) { if (mt == SSL3_MT_CERTIFICATE) { st->hand_state = TLS_ST_SR_CERT; return 1; } } else { if (mt == SSL3_MT_FINISHED) { st->hand_state = TLS_ST_SR_FINISHED; return 1; } } break; case TLS_ST_SR_CERT: if (s->session->peer == NULL) { if (mt == SSL3_MT_FINISHED) { st->hand_state = TLS_ST_SR_FINISHED; return 1; } } else { if (mt == SSL3_MT_CERTIFICATE_VERIFY) { st->hand_state = TLS_ST_SR_CERT_VRFY; return 1; } } break; case TLS_ST_SR_CERT_VRFY: if (mt == SSL3_MT_FINISHED) { st->hand_state = TLS_ST_SR_FINISHED; return 1; } break; case TLS_ST_OK: /* * Its never ok to start processing handshake messages in the middle of * early data (i.e. before we've received the end of early data alert) */ if (s->early_data_state == SSL_EARLY_DATA_READING) break; if (mt == SSL3_MT_CERTIFICATE && s->post_handshake_auth == SSL_PHA_REQUESTED) { st->hand_state = TLS_ST_SR_CERT; return 1; } if (mt == SSL3_MT_KEY_UPDATE) { st->hand_state = TLS_ST_SR_KEY_UPDATE; return 1; } break; } /* No valid transition found */ return 0; } /* * ossl_statem_server_read_transition() encapsulates the logic for the allowed * handshake state transitions when the server is reading messages from the * client. The message type that the client has sent is provided in |mt|. The * current state is in |s->statem.hand_state|. * * Return values are 1 for success (transition allowed) and 0 on error * (transition not allowed) */ int ossl_statem_server_read_transition(SSL *s, int mt) { OSSL_STATEM *st = &s->statem; if (SSL_IS_TLS13(s)) { if (!ossl_statem_server13_read_transition(s, mt)) goto err; return 1; } switch (st->hand_state) { default: break; case TLS_ST_BEFORE: case TLS_ST_OK: case DTLS_ST_SW_HELLO_VERIFY_REQUEST: if (mt == SSL3_MT_CLIENT_HELLO) { st->hand_state = TLS_ST_SR_CLNT_HELLO; return 1; } break; case TLS_ST_SW_SRVR_DONE: /* * If we get a CKE message after a ServerDone then either * 1) We didn't request a Certificate * OR * 2) If we did request one then * a) We allow no Certificate to be returned * AND * b) We are running SSL3 (in TLS1.0+ the client must return a 0 * list if we requested a certificate) */ if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) { if (s->s3->tmp.cert_request) { if (s->version == SSL3_VERSION) { if ((s->verify_mode & SSL_VERIFY_PEER) && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { /* * This isn't an unexpected message as such - we're just * not going to accept it because we require a client * cert. */ SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_OSSL_STATEM_SERVER_READ_TRANSITION, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); return 0; } st->hand_state = TLS_ST_SR_KEY_EXCH; return 1; } } else { st->hand_state = TLS_ST_SR_KEY_EXCH; return 1; } } else if (s->s3->tmp.cert_request) { if (mt == SSL3_MT_CERTIFICATE) { st->hand_state = TLS_ST_SR_CERT; return 1; } } break; case TLS_ST_SR_CERT: if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) { st->hand_state = TLS_ST_SR_KEY_EXCH; return 1; } break; case TLS_ST_SR_KEY_EXCH: /* * We should only process a CertificateVerify message if we have * received a Certificate from the client. If so then |s->session->peer| * will be non NULL. In some instances a CertificateVerify message is * not required even if the peer has sent a Certificate (e.g. such as in * the case of static DH). In that case |st->no_cert_verify| should be * set. */ if (s->session->peer == NULL || st->no_cert_verify) { if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) { /* * For the ECDH ciphersuites when the client sends its ECDH * pub key in a certificate, the CertificateVerify message is * not sent. Also for GOST ciphersuites when the client uses * its key from the certificate for key exchange. */ st->hand_state = TLS_ST_SR_CHANGE; return 1; } } else { if (mt == SSL3_MT_CERTIFICATE_VERIFY) { st->hand_state = TLS_ST_SR_CERT_VRFY; return 1; } } break; case TLS_ST_SR_CERT_VRFY: if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) { st->hand_state = TLS_ST_SR_CHANGE; return 1; } break; case TLS_ST_SR_CHANGE: #ifndef OPENSSL_NO_NEXTPROTONEG if (s->s3->npn_seen) { if (mt == SSL3_MT_NEXT_PROTO) { st->hand_state = TLS_ST_SR_NEXT_PROTO; return 1; } } else { #endif if (mt == SSL3_MT_FINISHED) { st->hand_state = TLS_ST_SR_FINISHED; return 1; } #ifndef OPENSSL_NO_NEXTPROTONEG } #endif break; #ifndef OPENSSL_NO_NEXTPROTONEG case TLS_ST_SR_NEXT_PROTO: if (mt == SSL3_MT_FINISHED) { st->hand_state = TLS_ST_SR_FINISHED; return 1; } break; #endif case TLS_ST_SW_FINISHED: if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) { st->hand_state = TLS_ST_SR_CHANGE; return 1; } break; } err: /* No valid transition found */ SSLfatal(s, SSL3_AD_UNEXPECTED_MESSAGE, SSL_F_OSSL_STATEM_SERVER_READ_TRANSITION, SSL_R_UNEXPECTED_MESSAGE); return 0; } /* * Should we send a ServerKeyExchange message? * * Valid return values are: * 1: Yes * 0: No */ static int send_server_key_exchange(SSL *s) { unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey; /* * only send a ServerKeyExchange if DH or fortezza but we have a * sign only certificate PSK: may send PSK identity hints For * ECC ciphersuites, we send a serverKeyExchange message only if * the cipher suite is either ECDH-anon or ECDHE. In other cases, * the server certificate contains the server's public key for * key exchange. */ if (alg_k & (SSL_kDHE | SSL_kECDHE) /* * PSK: send ServerKeyExchange if PSK identity hint if * provided */ #ifndef OPENSSL_NO_PSK /* Only send SKE if we have identity hint for plain PSK */ || ((alg_k & (SSL_kPSK | SSL_kRSAPSK)) && s->cert->psk_identity_hint) /* For other PSK always send SKE */ || (alg_k & (SSL_PSK & (SSL_kDHEPSK | SSL_kECDHEPSK))) #endif #ifndef OPENSSL_NO_SRP /* SRP: send ServerKeyExchange */ || (alg_k & SSL_kSRP) #endif ) { return 1; } return 0; } /* * Should we send a CertificateRequest message? * * Valid return values are: * 1: Yes * 0: No */ int send_certificate_request(SSL *s) { if ( /* don't request cert unless asked for it: */ s->verify_mode & SSL_VERIFY_PEER /* * don't request if post-handshake-only unless doing * post-handshake in TLSv1.3: */ && (!SSL_IS_TLS13(s) || !(s->verify_mode & SSL_VERIFY_POST_HANDSHAKE) || s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) /* * if SSL_VERIFY_CLIENT_ONCE is set, don't request cert * a second time: */ && (s->certreqs_sent < 1 || !(s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) /* * never request cert in anonymous ciphersuites (see * section "Certificate request" in SSL 3 drafts and in * RFC 2246): */ && (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) /* * ... except when the application insists on * verification (against the specs, but statem_clnt.c accepts * this for SSL 3) */ || (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) /* don't request certificate for SRP auth */ && !(s->s3->tmp.new_cipher->algorithm_auth & SSL_aSRP) /* * With normal PSK Certificates and Certificate Requests * are omitted */ && !(s->s3->tmp.new_cipher->algorithm_auth & SSL_aPSK)) { return 1; } return 0; } /* * ossl_statem_server13_write_transition() works out what handshake state to * move to next when a TLSv1.3 server is writing messages to be sent to the * client. */ static WRITE_TRAN ossl_statem_server13_write_transition(SSL *s) { OSSL_STATEM *st = &s->statem; /* * No case for TLS_ST_BEFORE, because at that stage we have not negotiated * TLSv1.3 yet, so that is handled by ossl_statem_server_write_transition() */ switch (st->hand_state) { default: /* Shouldn't happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_OSSL_STATEM_SERVER13_WRITE_TRANSITION, ERR_R_INTERNAL_ERROR); return WRITE_TRAN_ERROR; case TLS_ST_OK: if (s->key_update != SSL_KEY_UPDATE_NONE) { st->hand_state = TLS_ST_SW_KEY_UPDATE; return WRITE_TRAN_CONTINUE; } if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) { st->hand_state = TLS_ST_SW_CERT_REQ; return WRITE_TRAN_CONTINUE; } /* Try to read from the client instead */ return WRITE_TRAN_FINISHED; case TLS_ST_SR_CLNT_HELLO: st->hand_state = TLS_ST_SW_SRVR_HELLO; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_SRVR_HELLO: if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0 && s->hello_retry_request != SSL_HRR_COMPLETE) st->hand_state = TLS_ST_SW_CHANGE; else if (s->hello_retry_request == SSL_HRR_PENDING) st->hand_state = TLS_ST_EARLY_DATA; else st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_CHANGE: if (s->hello_retry_request == SSL_HRR_PENDING) st->hand_state = TLS_ST_EARLY_DATA; else st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_ENCRYPTED_EXTENSIONS: if (s->hit) st->hand_state = TLS_ST_SW_FINISHED; else if (send_certificate_request(s)) st->hand_state = TLS_ST_SW_CERT_REQ; else st->hand_state = TLS_ST_SW_CERT; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_CERT_REQ: if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) { s->post_handshake_auth = SSL_PHA_REQUESTED; st->hand_state = TLS_ST_OK; } else { st->hand_state = TLS_ST_SW_CERT; } return WRITE_TRAN_CONTINUE; case TLS_ST_SW_CERT: st->hand_state = TLS_ST_SW_CERT_VRFY; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_CERT_VRFY: st->hand_state = TLS_ST_SW_FINISHED; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_FINISHED: st->hand_state = TLS_ST_EARLY_DATA; return WRITE_TRAN_CONTINUE; case TLS_ST_EARLY_DATA: return WRITE_TRAN_FINISHED; case TLS_ST_SR_FINISHED: /* * Technically we have finished the handshake at this point, but we're * going to remain "in_init" for now and write out the session ticket * immediately. * TODO(TLS1.3): Perhaps we need to be able to control this behaviour * and give the application the opportunity to delay sending the * session ticket? */ if (s->post_handshake_auth == SSL_PHA_REQUESTED) s->post_handshake_auth = SSL_PHA_EXT_RECEIVED; st->hand_state = TLS_ST_SW_SESSION_TICKET; return WRITE_TRAN_CONTINUE; case TLS_ST_SR_KEY_UPDATE: if (s->key_update != SSL_KEY_UPDATE_NONE) { st->hand_state = TLS_ST_SW_KEY_UPDATE; return WRITE_TRAN_CONTINUE; } /* Fall through */ case TLS_ST_SW_KEY_UPDATE: case TLS_ST_SW_SESSION_TICKET: st->hand_state = TLS_ST_OK; return WRITE_TRAN_CONTINUE; } } /* * ossl_statem_server_write_transition() works out what handshake state to move * to next when the server is writing messages to be sent to the client. */ WRITE_TRAN ossl_statem_server_write_transition(SSL *s) { OSSL_STATEM *st = &s->statem; /* * Note that before the ClientHello we don't know what version we are going * to negotiate yet, so we don't take this branch until later */ if (SSL_IS_TLS13(s)) return ossl_statem_server13_write_transition(s); switch (st->hand_state) { default: /* Shouldn't happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_OSSL_STATEM_SERVER_WRITE_TRANSITION, ERR_R_INTERNAL_ERROR); return WRITE_TRAN_ERROR; case TLS_ST_OK: if (st->request_state == TLS_ST_SW_HELLO_REQ) { /* We must be trying to renegotiate */ st->hand_state = TLS_ST_SW_HELLO_REQ; st->request_state = TLS_ST_BEFORE; return WRITE_TRAN_CONTINUE; } /* Must be an incoming ClientHello */ if (!tls_setup_handshake(s)) { /* SSLfatal() already called */ return WRITE_TRAN_ERROR; } /* Fall through */ case TLS_ST_BEFORE: /* Just go straight to trying to read from the client */ return WRITE_TRAN_FINISHED; case TLS_ST_SW_HELLO_REQ: st->hand_state = TLS_ST_OK; return WRITE_TRAN_CONTINUE; case TLS_ST_SR_CLNT_HELLO: if (SSL_IS_DTLS(s) && !s->d1->cookie_verified && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)) { st->hand_state = DTLS_ST_SW_HELLO_VERIFY_REQUEST; } else if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) { /* We must have rejected the renegotiation */ st->hand_state = TLS_ST_OK; return WRITE_TRAN_CONTINUE; } else { st->hand_state = TLS_ST_SW_SRVR_HELLO; } return WRITE_TRAN_CONTINUE; case DTLS_ST_SW_HELLO_VERIFY_REQUEST: return WRITE_TRAN_FINISHED; case TLS_ST_SW_SRVR_HELLO: if (s->hit) { if (s->ext.ticket_expected) st->hand_state = TLS_ST_SW_SESSION_TICKET; else st->hand_state = TLS_ST_SW_CHANGE; } else { /* Check if it is anon DH or anon ECDH, */ /* normal PSK or SRP */ if (!(s->s3->tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP | SSL_aPSK))) { st->hand_state = TLS_ST_SW_CERT; } else if (send_server_key_exchange(s)) { st->hand_state = TLS_ST_SW_KEY_EXCH; } else if (send_certificate_request(s)) { st->hand_state = TLS_ST_SW_CERT_REQ; } else { st->hand_state = TLS_ST_SW_SRVR_DONE; } } return WRITE_TRAN_CONTINUE; case TLS_ST_SW_CERT: if (s->ext.status_expected) { st->hand_state = TLS_ST_SW_CERT_STATUS; return WRITE_TRAN_CONTINUE; } /* Fall through */ case TLS_ST_SW_CERT_STATUS: if (send_server_key_exchange(s)) { st->hand_state = TLS_ST_SW_KEY_EXCH; return WRITE_TRAN_CONTINUE; } /* Fall through */ case TLS_ST_SW_KEY_EXCH: if (send_certificate_request(s)) { st->hand_state = TLS_ST_SW_CERT_REQ; return WRITE_TRAN_CONTINUE; } /* Fall through */ case TLS_ST_SW_CERT_REQ: st->hand_state = TLS_ST_SW_SRVR_DONE; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_SRVR_DONE: return WRITE_TRAN_FINISHED; case TLS_ST_SR_FINISHED: if (s->hit) { st->hand_state = TLS_ST_OK; return WRITE_TRAN_CONTINUE; } else if (s->ext.ticket_expected) { st->hand_state = TLS_ST_SW_SESSION_TICKET; } else { st->hand_state = TLS_ST_SW_CHANGE; } return WRITE_TRAN_CONTINUE; case TLS_ST_SW_SESSION_TICKET: st->hand_state = TLS_ST_SW_CHANGE; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_CHANGE: st->hand_state = TLS_ST_SW_FINISHED; return WRITE_TRAN_CONTINUE; case TLS_ST_SW_FINISHED: if (s->hit) { return WRITE_TRAN_FINISHED; } st->hand_state = TLS_ST_OK; return WRITE_TRAN_CONTINUE; } } /* * Perform any pre work that needs to be done prior to sending a message from * the server to the client. */ WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst) { OSSL_STATEM *st = &s->statem; switch (st->hand_state) { default: /* No pre work to be done */ break; case TLS_ST_SW_HELLO_REQ: s->shutdown = 0; if (SSL_IS_DTLS(s)) dtls1_clear_sent_buffer(s); break; case DTLS_ST_SW_HELLO_VERIFY_REQUEST: s->shutdown = 0; if (SSL_IS_DTLS(s)) { dtls1_clear_sent_buffer(s); /* We don't buffer this message so don't use the timer */ st->use_timer = 0; } break; case TLS_ST_SW_SRVR_HELLO: if (SSL_IS_DTLS(s)) { /* * Messages we write from now on should be buffered and * retransmitted if necessary, so we need to use the timer now */ st->use_timer = 1; } break; case TLS_ST_SW_SRVR_DONE: #ifndef OPENSSL_NO_SCTP if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) { /* Calls SSLfatal() as required */ return dtls_wait_for_dry(s); } #endif return WORK_FINISHED_CONTINUE; case TLS_ST_SW_SESSION_TICKET: if (SSL_IS_TLS13(s)) { /* * Actually this is the end of the handshake, but we're going * straight into writing the session ticket out. So we finish off * the handshake, but keep the various buffers active. * * Calls SSLfatal as required. */ return tls_finish_handshake(s, wst, 0, 0); } if (SSL_IS_DTLS(s)) { /* * We're into the last flight. We don't retransmit the last flight * unless we need to, so we don't use the timer */ st->use_timer = 0; } break; case TLS_ST_SW_CHANGE: if (SSL_IS_TLS13(s)) break; s->session->cipher = s->s3->tmp.new_cipher; if (!s->method->ssl3_enc->setup_key_block(s)) { /* SSLfatal() already called */ return WORK_ERROR; } if (SSL_IS_DTLS(s)) { /* * We're into the last flight. We don't retransmit the last flight * unless we need to, so we don't use the timer. This might have * already been set to 0 if we sent a NewSessionTicket message, * but we'll set it again here in case we didn't. */ st->use_timer = 0; } return WORK_FINISHED_CONTINUE; case TLS_ST_EARLY_DATA: if (s->early_data_state != SSL_EARLY_DATA_ACCEPTING && (s->s3->flags & TLS1_FLAGS_STATELESS) == 0) return WORK_FINISHED_CONTINUE; /* Fall through */ case TLS_ST_OK: /* Calls SSLfatal() as required */ return tls_finish_handshake(s, wst, 1, 1); } return WORK_FINISHED_CONTINUE; } /* * Perform any work that needs to be done after sending a message from the * server to the client. */ WORK_STATE ossl_statem_server_post_work(SSL *s, WORK_STATE wst) { OSSL_STATEM *st = &s->statem; s->init_num = 0; switch (st->hand_state) { default: /* No post work to be done */ break; case TLS_ST_SW_HELLO_REQ: if (statem_flush(s) != 1) return WORK_MORE_A; if (!ssl3_init_finished_mac(s)) { /* SSLfatal() already called */ return WORK_ERROR; } break; case DTLS_ST_SW_HELLO_VERIFY_REQUEST: if (statem_flush(s) != 1) return WORK_MORE_A; /* HelloVerifyRequest resets Finished MAC */ if (s->version != DTLS1_BAD_VER && !ssl3_init_finished_mac(s)) { /* SSLfatal() already called */ return WORK_ERROR; } /* * The next message should be another ClientHello which we need to * treat like it was the first packet */ s->first_packet = 1; break; case TLS_ST_SW_SRVR_HELLO: if (SSL_IS_TLS13(s) && s->hello_retry_request == SSL_HRR_PENDING) { if ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) == 0 && statem_flush(s) != 1) return WORK_MORE_A; break; } #ifndef OPENSSL_NO_SCTP if (SSL_IS_DTLS(s) && s->hit) { unsigned char sctpauthkey[64]; char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)]; /* * Add new shared key for SCTP-Auth, will be ignored if no * SCTP used. */ memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL, sizeof(DTLS1_SCTP_AUTH_LABEL)); if (SSL_export_keying_material(s, sctpauthkey, sizeof(sctpauthkey), labelbuffer, sizeof(labelbuffer), NULL, 0, 0) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_OSSL_STATEM_SERVER_POST_WORK, ERR_R_INTERNAL_ERROR); return WORK_ERROR; } BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY, sizeof(sctpauthkey), sctpauthkey); } #endif if (!SSL_IS_TLS13(s) || ((s->options & SSL_OP_ENABLE_MIDDLEBOX_COMPAT) != 0 && s->hello_retry_request != SSL_HRR_COMPLETE)) break; /* Fall through */ case TLS_ST_SW_CHANGE: if (s->hello_retry_request == SSL_HRR_PENDING) { if (!statem_flush(s)) return WORK_MORE_A; break; } /* * TODO(TLS1.3): This actually causes a problem. We don't yet know * whether the next record we are going to receive is an unencrypted * alert, or an encrypted handshake message. We're going to need * something clever in the record layer for this. */ if (SSL_IS_TLS13(s)) { if (!s->method->ssl3_enc->setup_key_block(s) || !s->method->ssl3_enc->change_cipher_state(s, SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_WRITE)) { /* SSLfatal() already called */ return WORK_ERROR; } if (s->ext.early_data != SSL_EARLY_DATA_ACCEPTED && !s->method->ssl3_enc->change_cipher_state(s, SSL3_CC_HANDSHAKE |SSL3_CHANGE_CIPHER_SERVER_READ)) { /* SSLfatal() already called */ return WORK_ERROR; } break; } #ifndef OPENSSL_NO_SCTP if (SSL_IS_DTLS(s) && !s->hit) { /* * Change to new shared key of SCTP-Auth, will be ignored if * no SCTP used. */ BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL); } #endif if (!s->method->ssl3_enc->change_cipher_state(s, SSL3_CHANGE_CIPHER_SERVER_WRITE)) { /* SSLfatal() already called */ return WORK_ERROR; } if (SSL_IS_DTLS(s)) dtls1_reset_seq_numbers(s, SSL3_CC_WRITE); break; case TLS_ST_SW_SRVR_DONE: if (statem_flush(s) != 1) return WORK_MORE_A; break; case TLS_ST_SW_FINISHED: if (statem_flush(s) != 1) return WORK_MORE_A; #ifndef OPENSSL_NO_SCTP if (SSL_IS_DTLS(s) && s->hit) { /* * Change to new shared key of SCTP-Auth, will be ignored if * no SCTP used. */ BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL); } #endif if (SSL_IS_TLS13(s)) { if (!s->method->ssl3_enc->generate_master_secret(s, s->master_secret, s->handshake_secret, 0, &s->session->master_key_length) || !s->method->ssl3_enc->change_cipher_state(s, SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_SERVER_WRITE)) /* SSLfatal() already called */ return WORK_ERROR; } break; case TLS_ST_SW_CERT_REQ: if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) { if (statem_flush(s) != 1) return WORK_MORE_A; } break; case TLS_ST_SW_KEY_UPDATE: if (statem_flush(s) != 1) return WORK_MORE_A; if (!tls13_update_key(s, 1)) { /* SSLfatal() already called */ return WORK_ERROR; } break; case TLS_ST_SW_SESSION_TICKET: if (SSL_IS_TLS13(s) && statem_flush(s) != 1) return WORK_MORE_A; break; } return WORK_FINISHED_CONTINUE; } /* * Get the message construction function and message type for sending from the * server * * Valid return values are: * 1: Success * 0: Error */ int ossl_statem_server_construct_message(SSL *s, WPACKET *pkt, confunc_f *confunc, int *mt) { OSSL_STATEM *st = &s->statem; switch (st->hand_state) { default: /* Shouldn't happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_OSSL_STATEM_SERVER_CONSTRUCT_MESSAGE, SSL_R_BAD_HANDSHAKE_STATE); return 0; case TLS_ST_SW_CHANGE: if (SSL_IS_DTLS(s)) *confunc = dtls_construct_change_cipher_spec; else *confunc = tls_construct_change_cipher_spec; *mt = SSL3_MT_CHANGE_CIPHER_SPEC; break; case DTLS_ST_SW_HELLO_VERIFY_REQUEST: *confunc = dtls_construct_hello_verify_request; *mt = DTLS1_MT_HELLO_VERIFY_REQUEST; break; case TLS_ST_SW_HELLO_REQ: /* No construction function needed */ *confunc = NULL; *mt = SSL3_MT_HELLO_REQUEST; break; case TLS_ST_SW_SRVR_HELLO: *confunc = tls_construct_server_hello; *mt = SSL3_MT_SERVER_HELLO; break; case TLS_ST_SW_CERT: *confunc = tls_construct_server_certificate; *mt = SSL3_MT_CERTIFICATE; break; case TLS_ST_SW_CERT_VRFY: *confunc = tls_construct_cert_verify; *mt = SSL3_MT_CERTIFICATE_VERIFY; break; case TLS_ST_SW_KEY_EXCH: *confunc = tls_construct_server_key_exchange; *mt = SSL3_MT_SERVER_KEY_EXCHANGE; break; case TLS_ST_SW_CERT_REQ: *confunc = tls_construct_certificate_request; *mt = SSL3_MT_CERTIFICATE_REQUEST; break; case TLS_ST_SW_SRVR_DONE: *confunc = tls_construct_server_done; *mt = SSL3_MT_SERVER_DONE; break; case TLS_ST_SW_SESSION_TICKET: *confunc = tls_construct_new_session_ticket; *mt = SSL3_MT_NEWSESSION_TICKET; break; case TLS_ST_SW_CERT_STATUS: *confunc = tls_construct_cert_status; *mt = SSL3_MT_CERTIFICATE_STATUS; break; case TLS_ST_SW_FINISHED: *confunc = tls_construct_finished; *mt = SSL3_MT_FINISHED; break; case TLS_ST_EARLY_DATA: *confunc = NULL; *mt = SSL3_MT_DUMMY; break; case TLS_ST_SW_ENCRYPTED_EXTENSIONS: *confunc = tls_construct_encrypted_extensions; *mt = SSL3_MT_ENCRYPTED_EXTENSIONS; break; case TLS_ST_SW_KEY_UPDATE: *confunc = tls_construct_key_update; *mt = SSL3_MT_KEY_UPDATE; break; } return 1; } /* * Maximum size (excluding the Handshake header) of a ClientHello message, * calculated as follows: * * 2 + # client_version * 32 + # only valid length for random * 1 + # length of session_id * 32 + # maximum size for session_id * 2 + # length of cipher suites * 2^16-2 + # maximum length of cipher suites array * 1 + # length of compression_methods * 2^8-1 + # maximum length of compression methods * 2 + # length of extensions * 2^16-1 # maximum length of extensions */ #define CLIENT_HELLO_MAX_LENGTH 131396 #define CLIENT_KEY_EXCH_MAX_LENGTH 2048 #define NEXT_PROTO_MAX_LENGTH 514 /* * Returns the maximum allowed length for the current message that we are * reading. Excludes the message header. */ size_t ossl_statem_server_max_message_size(SSL *s) { OSSL_STATEM *st = &s->statem; switch (st->hand_state) { default: /* Shouldn't happen */ return 0; case TLS_ST_SR_CLNT_HELLO: return CLIENT_HELLO_MAX_LENGTH; case TLS_ST_SR_END_OF_EARLY_DATA: return END_OF_EARLY_DATA_MAX_LENGTH; case TLS_ST_SR_CERT: return s->max_cert_list; case TLS_ST_SR_KEY_EXCH: return CLIENT_KEY_EXCH_MAX_LENGTH; case TLS_ST_SR_CERT_VRFY: return SSL3_RT_MAX_PLAIN_LENGTH; #ifndef OPENSSL_NO_NEXTPROTONEG case TLS_ST_SR_NEXT_PROTO: return NEXT_PROTO_MAX_LENGTH; #endif case TLS_ST_SR_CHANGE: return CCS_MAX_LENGTH; case TLS_ST_SR_FINISHED: return FINISHED_MAX_LENGTH; case TLS_ST_SR_KEY_UPDATE: return KEY_UPDATE_MAX_LENGTH; } } /* * Process a message that the server has received from the client. */ MSG_PROCESS_RETURN ossl_statem_server_process_message(SSL *s, PACKET *pkt) { OSSL_STATEM *st = &s->statem; switch (st->hand_state) { default: /* Shouldn't happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_OSSL_STATEM_SERVER_PROCESS_MESSAGE, ERR_R_INTERNAL_ERROR); return MSG_PROCESS_ERROR; case TLS_ST_SR_CLNT_HELLO: return tls_process_client_hello(s, pkt); case TLS_ST_SR_END_OF_EARLY_DATA: return tls_process_end_of_early_data(s, pkt); case TLS_ST_SR_CERT: return tls_process_client_certificate(s, pkt); case TLS_ST_SR_KEY_EXCH: return tls_process_client_key_exchange(s, pkt); case TLS_ST_SR_CERT_VRFY: return tls_process_cert_verify(s, pkt); #ifndef OPENSSL_NO_NEXTPROTONEG case TLS_ST_SR_NEXT_PROTO: return tls_process_next_proto(s, pkt); #endif case TLS_ST_SR_CHANGE: return tls_process_change_cipher_spec(s, pkt); case TLS_ST_SR_FINISHED: return tls_process_finished(s, pkt); case TLS_ST_SR_KEY_UPDATE: return tls_process_key_update(s, pkt); } } /* * Perform any further processing required following the receipt of a message * from the client */ WORK_STATE ossl_statem_server_post_process_message(SSL *s, WORK_STATE wst) { OSSL_STATEM *st = &s->statem; switch (st->hand_state) { default: /* Shouldn't happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_OSSL_STATEM_SERVER_POST_PROCESS_MESSAGE, ERR_R_INTERNAL_ERROR); return WORK_ERROR; case TLS_ST_SR_CLNT_HELLO: return tls_post_process_client_hello(s, wst); case TLS_ST_SR_KEY_EXCH: return tls_post_process_client_key_exchange(s, wst); } } #ifndef OPENSSL_NO_SRP /* Returns 1 on success, 0 for retryable error, -1 for fatal error */ static int ssl_check_srp_ext_ClientHello(SSL *s) { int ret; int al = SSL_AD_UNRECOGNIZED_NAME; if ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_kSRP) && (s->srp_ctx.TLS_ext_srp_username_callback != NULL)) { if (s->srp_ctx.login == NULL) { /* * RFC 5054 says SHOULD reject, we do so if There is no srp * login name */ SSLfatal(s, SSL_AD_UNKNOWN_PSK_IDENTITY, SSL_F_SSL_CHECK_SRP_EXT_CLIENTHELLO, SSL_R_PSK_IDENTITY_NOT_FOUND); return -1; } else { ret = SSL_srp_server_param_with_username(s, &al); if (ret < 0) return 0; if (ret == SSL3_AL_FATAL) { SSLfatal(s, al, SSL_F_SSL_CHECK_SRP_EXT_CLIENTHELLO, al == SSL_AD_UNKNOWN_PSK_IDENTITY ? SSL_R_PSK_IDENTITY_NOT_FOUND : SSL_R_CLIENTHELLO_TLSEXT); return -1; } } } return 1; } #endif int dtls_raw_hello_verify_request(WPACKET *pkt, unsigned char *cookie, size_t cookie_len) { /* Always use DTLS 1.0 version: see RFC 6347 */ if (!WPACKET_put_bytes_u16(pkt, DTLS1_VERSION) || !WPACKET_sub_memcpy_u8(pkt, cookie, cookie_len)) return 0; return 1; } int dtls_construct_hello_verify_request(SSL *s, WPACKET *pkt) { unsigned int cookie_leni; if (s->ctx->app_gen_cookie_cb == NULL || s->ctx->app_gen_cookie_cb(s, s->d1->cookie, &cookie_leni) == 0 || cookie_leni > 255) { SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_DTLS_CONSTRUCT_HELLO_VERIFY_REQUEST, SSL_R_COOKIE_GEN_CALLBACK_FAILURE); return 0; } s->d1->cookie_len = cookie_leni; if (!dtls_raw_hello_verify_request(pkt, s->d1->cookie, s->d1->cookie_len)) { SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_DTLS_CONSTRUCT_HELLO_VERIFY_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #ifndef OPENSSL_NO_EC /*- * ssl_check_for_safari attempts to fingerprint Safari using OS X * SecureTransport using the TLS extension block in |hello|. * Safari, since 10.6, sends exactly these extensions, in this order: * SNI, * elliptic_curves * ec_point_formats * signature_algorithms (for TLSv1.2 only) * * We wish to fingerprint Safari because they broke ECDHE-ECDSA support in 10.8, * but they advertise support. So enabling ECDHE-ECDSA ciphers breaks them. * Sadly we cannot differentiate 10.6, 10.7 and 10.8.4 (which work), from * 10.8..10.8.3 (which don't work). */ static void ssl_check_for_safari(SSL *s, const CLIENTHELLO_MSG *hello) { static const unsigned char kSafariExtensionsBlock[] = { 0x00, 0x0a, /* elliptic_curves extension */ 0x00, 0x08, /* 8 bytes */ 0x00, 0x06, /* 6 bytes of curve ids */ 0x00, 0x17, /* P-256 */ 0x00, 0x18, /* P-384 */ 0x00, 0x19, /* P-521 */ 0x00, 0x0b, /* ec_point_formats */ 0x00, 0x02, /* 2 bytes */ 0x01, /* 1 point format */ 0x00, /* uncompressed */ /* The following is only present in TLS 1.2 */ 0x00, 0x0d, /* signature_algorithms */ 0x00, 0x0c, /* 12 bytes */ 0x00, 0x0a, /* 10 bytes */ 0x05, 0x01, /* SHA-384/RSA */ 0x04, 0x01, /* SHA-256/RSA */ 0x02, 0x01, /* SHA-1/RSA */ 0x04, 0x03, /* SHA-256/ECDSA */ 0x02, 0x03, /* SHA-1/ECDSA */ }; /* Length of the common prefix (first two extensions). */ static const size_t kSafariCommonExtensionsLength = 18; unsigned int type; PACKET sni, tmppkt; size_t ext_len; tmppkt = hello->extensions; if (!PACKET_forward(&tmppkt, 2) || !PACKET_get_net_2(&tmppkt, &type) || !PACKET_get_length_prefixed_2(&tmppkt, &sni)) { return; } if (type != TLSEXT_TYPE_server_name) return; ext_len = TLS1_get_client_version(s) >= TLS1_2_VERSION ? sizeof(kSafariExtensionsBlock) : kSafariCommonExtensionsLength; s->s3->is_probably_safari = PACKET_equal(&tmppkt, kSafariExtensionsBlock, ext_len); } #endif /* !OPENSSL_NO_EC */ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt) { /* |cookie| will only be initialized for DTLS. */ PACKET session_id, compression, extensions, cookie; static const unsigned char null_compression = 0; CLIENTHELLO_MSG *clienthello = NULL; /* Check if this is actually an unexpected renegotiation ClientHello */ if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) { if (!ossl_assert(!SSL_IS_TLS13(s))) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); goto err; } if ((s->options & SSL_OP_NO_RENEGOTIATION) != 0 || (!s->s3->send_connection_binding && (s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) == 0)) { ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); return MSG_PROCESS_FINISHED_READING; } s->renegotiate = 1; s->new_session = 1; } clienthello = OPENSSL_zalloc(sizeof(*clienthello)); if (clienthello == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); goto err; } /* * First, parse the raw ClientHello data into the CLIENTHELLO_MSG structure. */ clienthello->isv2 = RECORD_LAYER_is_sslv2_record(&s->rlayer); PACKET_null_init(&cookie); if (clienthello->isv2) { unsigned int mt; if (!SSL_IS_FIRST_HANDSHAKE(s) || s->hello_retry_request != SSL_HRR_NONE) { SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_UNEXPECTED_MESSAGE); goto err; } /*- * An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2 * header is sent directly on the wire, not wrapped as a TLS * record. Our record layer just processes the message length and passes * the rest right through. Its format is: * Byte Content * 0-1 msg_length - decoded by the record layer * 2 msg_type - s->init_msg points here * 3-4 version * 5-6 cipher_spec_length * 7-8 session_id_length * 9-10 challenge_length * ... ... */ if (!PACKET_get_1(pkt, &mt) || mt != SSL2_MT_CLIENT_HELLO) { /* * Should never happen. We should have tested this in the record * layer in order to have determined that this is a SSLv2 record * in the first place */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); goto err; } } if (!PACKET_get_net_2(pkt, &clienthello->legacy_version)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT); goto err; } /* Parse the message and load client random. */ if (clienthello->isv2) { /* * Handle an SSLv2 backwards compatible ClientHello * Note, this is only for SSLv3+ using the backward compatible format. * Real SSLv2 is not supported, and is rejected below. */ unsigned int ciphersuite_len, session_id_len, challenge_len; PACKET challenge; if (!PACKET_get_net_2(pkt, &ciphersuite_len) || !PACKET_get_net_2(pkt, &session_id_len) || !PACKET_get_net_2(pkt, &challenge_len)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_RECORD_LENGTH_MISMATCH); goto err; } if (session_id_len > SSL_MAX_SSL_SESSION_ID_LENGTH) { SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH); goto err; } if (!PACKET_get_sub_packet(pkt, &clienthello->ciphersuites, ciphersuite_len) || !PACKET_copy_bytes(pkt, clienthello->session_id, session_id_len) || !PACKET_get_sub_packet(pkt, &challenge, challenge_len) /* No extensions. */ || PACKET_remaining(pkt) != 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_RECORD_LENGTH_MISMATCH); goto err; } clienthello->session_id_len = session_id_len; /* Load the client random and compression list. We use SSL3_RANDOM_SIZE * here rather than sizeof(clienthello->random) because that is the limit * for SSLv3 and it is fixed. It won't change even if * sizeof(clienthello->random) does. */ challenge_len = challenge_len > SSL3_RANDOM_SIZE ? SSL3_RANDOM_SIZE : challenge_len; memset(clienthello->random, 0, SSL3_RANDOM_SIZE); if (!PACKET_copy_bytes(&challenge, clienthello->random + SSL3_RANDOM_SIZE - challenge_len, challenge_len) /* Advertise only null compression. */ || !PACKET_buf_init(&compression, &null_compression, 1)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); goto err; } PACKET_null_init(&clienthello->extensions); } else { /* Regular ClientHello. */ if (!PACKET_copy_bytes(pkt, clienthello->random, SSL3_RANDOM_SIZE) || !PACKET_get_length_prefixed_1(pkt, &session_id) || !PACKET_copy_all(&session_id, clienthello->session_id, SSL_MAX_SSL_SESSION_ID_LENGTH, &clienthello->session_id_len)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH); goto err; } if (SSL_IS_DTLS(s)) { if (!PACKET_get_length_prefixed_1(pkt, &cookie)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH); goto err; } if (!PACKET_copy_all(&cookie, clienthello->dtls_cookie, DTLS1_COOKIE_LENGTH, &clienthello->dtls_cookie_len)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); goto err; } /* * If we require cookies and this ClientHello doesn't contain one, * just return since we do not want to allocate any memory yet. * So check cookie length... */ if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) { if (clienthello->dtls_cookie_len == 0) return MSG_PROCESS_FINISHED_READING; } } if (!PACKET_get_length_prefixed_2(pkt, &clienthello->ciphersuites)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH); goto err; } if (!PACKET_get_length_prefixed_1(pkt, &compression)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH); goto err; } /* Could be empty. */ if (PACKET_remaining(pkt) == 0) { PACKET_null_init(&clienthello->extensions); } else { if (!PACKET_get_length_prefixed_2(pkt, &clienthello->extensions) || PACKET_remaining(pkt) != 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH); goto err; } } } if (!PACKET_copy_all(&compression, clienthello->compressions, MAX_COMPRESSIONS_SIZE, &clienthello->compressions_len)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); goto err; } /* Preserve the raw extensions PACKET for later use */ extensions = clienthello->extensions; if (!tls_collect_extensions(s, &extensions, SSL_EXT_CLIENT_HELLO, &clienthello->pre_proc_exts, &clienthello->pre_proc_exts_len, 1)) { /* SSLfatal already been called */ goto err; } s->clienthello = clienthello; return MSG_PROCESS_CONTINUE_PROCESSING; err: if (clienthello != NULL) OPENSSL_free(clienthello->pre_proc_exts); OPENSSL_free(clienthello); return MSG_PROCESS_ERROR; } static int tls_early_post_process_client_hello(SSL *s) { unsigned int j; int i, al = SSL_AD_INTERNAL_ERROR; int protverr; size_t loop; unsigned long id; #ifndef OPENSSL_NO_COMP SSL_COMP *comp = NULL; #endif const SSL_CIPHER *c; STACK_OF(SSL_CIPHER) *ciphers = NULL; STACK_OF(SSL_CIPHER) *scsvs = NULL; CLIENTHELLO_MSG *clienthello = s->clienthello; DOWNGRADE dgrd = DOWNGRADE_NONE; /* Finished parsing the ClientHello, now we can start processing it */ /* Give the ClientHello callback a crack at things */ if (s->ctx->client_hello_cb != NULL) { /* A failure in the ClientHello callback terminates the connection. */ switch (s->ctx->client_hello_cb(s, &al, s->ctx->client_hello_cb_arg)) { case SSL_CLIENT_HELLO_SUCCESS: break; case SSL_CLIENT_HELLO_RETRY: s->rwstate = SSL_CLIENT_HELLO_CB; return -1; case SSL_CLIENT_HELLO_ERROR: default: SSLfatal(s, al, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_CALLBACK_FAILED); goto err; } } /* Set up the client_random */ memcpy(s->s3->client_random, clienthello->random, SSL3_RANDOM_SIZE); /* Choose the version */ if (clienthello->isv2) { if (clienthello->legacy_version == SSL2_VERSION || (clienthello->legacy_version & 0xff00) != (SSL3_VERSION_MAJOR << 8)) { /* * This is real SSLv2 or something completely unknown. We don't * support it. */ SSLfatal(s, SSL_AD_PROTOCOL_VERSION, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL); goto err; } /* SSLv3/TLS */ s->client_version = clienthello->legacy_version; } /* * Do SSL/TLS version negotiation if applicable. For DTLS we just check * versions are potentially compatible. Version negotiation comes later. */ if (!SSL_IS_DTLS(s)) { protverr = ssl_choose_server_version(s, clienthello, &dgrd); } else if (s->method->version != DTLS_ANY_VERSION && DTLS_VERSION_LT((int)clienthello->legacy_version, s->version)) { protverr = SSL_R_VERSION_TOO_LOW; } else { protverr = 0; } if (protverr) { if (SSL_IS_FIRST_HANDSHAKE(s)) { /* like ssl3_get_record, send alert using remote version number */ s->version = s->client_version = clienthello->legacy_version; } SSLfatal(s, SSL_AD_PROTOCOL_VERSION, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, protverr); goto err; } /* TLSv1.3 specifies that a ClientHello must end on a record boundary */ if (SSL_IS_TLS13(s) && RECORD_LAYER_processed_read_pending(&s->rlayer)) { SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_NOT_ON_RECORD_BOUNDARY); goto err; } if (SSL_IS_DTLS(s)) { /* Empty cookie was already handled above by returning early. */ if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) { if (s->ctx->app_verify_cookie_cb != NULL) { if (s->ctx->app_verify_cookie_cb(s, clienthello->dtls_cookie, clienthello->dtls_cookie_len) == 0) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH); goto err; /* else cookie verification succeeded */ } /* default verification */ } else if (s->d1->cookie_len != clienthello->dtls_cookie_len || memcmp(clienthello->dtls_cookie, s->d1->cookie, s->d1->cookie_len) != 0) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH); goto err; } s->d1->cookie_verified = 1; } if (s->method->version == DTLS_ANY_VERSION) { protverr = ssl_choose_server_version(s, clienthello, &dgrd); if (protverr != 0) { s->version = s->client_version; SSLfatal(s, SSL_AD_PROTOCOL_VERSION, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, protverr); goto err; } } } s->hit = 0; if (!ssl_cache_cipherlist(s, &clienthello->ciphersuites, clienthello->isv2) || !bytes_to_cipher_list(s, &clienthello->ciphersuites, &ciphers, &scsvs, clienthello->isv2, 1)) { /* SSLfatal() already called */ goto err; } s->s3->send_connection_binding = 0; /* Check what signalling cipher-suite values were received. */ if (scsvs != NULL) { for(i = 0; i < sk_SSL_CIPHER_num(scsvs); i++) { c = sk_SSL_CIPHER_value(scsvs, i); if (SSL_CIPHER_get_id(c) == SSL3_CK_SCSV) { if (s->renegotiate) { /* SCSV is fatal if renegotiating */ SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_SCSV_RECEIVED_WHEN_RENEGOTIATING); goto err; } s->s3->send_connection_binding = 1; } else if (SSL_CIPHER_get_id(c) == SSL3_CK_FALLBACK_SCSV && !ssl_check_version_downgrade(s)) { /* * This SCSV indicates that the client previously tried * a higher version. We should fail if the current version * is an unexpected downgrade, as that indicates that the first * connection may have been tampered with in order to trigger * an insecure downgrade. */ SSLfatal(s, SSL_AD_INAPPROPRIATE_FALLBACK, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_INAPPROPRIATE_FALLBACK); goto err; } } } /* For TLSv1.3 we must select the ciphersuite *before* session resumption */ if (SSL_IS_TLS13(s)) { const SSL_CIPHER *cipher = ssl3_choose_cipher(s, ciphers, SSL_get_ciphers(s)); if (cipher == NULL) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_NO_SHARED_CIPHER); goto err; } if (s->hello_retry_request == SSL_HRR_PENDING && (s->s3->tmp.new_cipher == NULL || s->s3->tmp.new_cipher->id != cipher->id)) { /* * A previous HRR picked a different ciphersuite to the one we * just selected. Something must have changed. */ SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_BAD_CIPHER); goto err; } s->s3->tmp.new_cipher = cipher; } /* We need to do this before getting the session */ if (!tls_parse_extension(s, TLSEXT_IDX_extended_master_secret, SSL_EXT_CLIENT_HELLO, clienthello->pre_proc_exts, NULL, 0)) { /* SSLfatal() already called */ goto err; } /* * We don't allow resumption in a backwards compatible ClientHello. * TODO(openssl-team): in TLS1.1+, session_id MUST be empty. * * Versions before 0.9.7 always allow clients to resume sessions in * renegotiation. 0.9.7 and later allow this by default, but optionally * ignore resumption requests with flag * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather * than a change to default behavior so that applications relying on * this for security won't even compile against older library versions). * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to * request renegotiation but not a new session (s->new_session remains * unset): for servers, this essentially just means that the * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be * ignored. */ if (clienthello->isv2 || (s->new_session && (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) { if (!ssl_get_new_session(s, 1)) { /* SSLfatal() already called */ goto err; } } else { i = ssl_get_prev_session(s, clienthello); if (i == 1) { /* previous session */ s->hit = 1; } else if (i == -1) { /* SSLfatal() already called */ goto err; } else { /* i == 0 */ if (!ssl_get_new_session(s, 1)) { /* SSLfatal() already called */ goto err; } } } if (SSL_IS_TLS13(s)) { memcpy(s->tmp_session_id, s->clienthello->session_id, s->clienthello->session_id_len); s->tmp_session_id_len = s->clienthello->session_id_len; } /* * If it is a hit, check that the cipher is in the list. In TLSv1.3 we check * ciphersuite compatibility with the session as part of resumption. */ if (!SSL_IS_TLS13(s) && s->hit) { j = 0; id = s->session->cipher->id; #ifdef CIPHER_DEBUG fprintf(stderr, "client sent %d ciphers\n", sk_SSL_CIPHER_num(ciphers)); #endif for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) { c = sk_SSL_CIPHER_value(ciphers, i); #ifdef CIPHER_DEBUG fprintf(stderr, "client [%2d of %2d]:%s\n", i, sk_SSL_CIPHER_num(ciphers), SSL_CIPHER_get_name(c)); #endif if (c->id == id) { j = 1; break; } } if (j == 0) { /* * we need to have the cipher in the cipher list if we are asked * to reuse it */ SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_REQUIRED_CIPHER_MISSING); goto err; } } for (loop = 0; loop < clienthello->compressions_len; loop++) { if (clienthello->compressions[loop] == 0) break; } if (loop >= clienthello->compressions_len) { /* no compress */ SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_NO_COMPRESSION_SPECIFIED); goto err; } #ifndef OPENSSL_NO_EC if (s->options & SSL_OP_SAFARI_ECDHE_ECDSA_BUG) ssl_check_for_safari(s, clienthello); #endif /* !OPENSSL_NO_EC */ /* TLS extensions */ if (!tls_parse_all_extensions(s, SSL_EXT_CLIENT_HELLO, clienthello->pre_proc_exts, NULL, 0, 1)) { /* SSLfatal() already called */ goto err; } /* * Check if we want to use external pre-shared secret for this handshake * for not reused session only. We need to generate server_random before * calling tls_session_secret_cb in order to allow SessionTicket * processing to use it in key derivation. */ { unsigned char *pos; pos = s->s3->server_random; if (ssl_fill_hello_random(s, 1, pos, SSL3_RANDOM_SIZE, dgrd) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); goto err; } } if (!s->hit && s->version >= TLS1_VERSION && !SSL_IS_TLS13(s) && !SSL_IS_DTLS(s) && s->ext.session_secret_cb) { const SSL_CIPHER *pref_cipher = NULL; /* * s->session->master_key_length is a size_t, but this is an int for * backwards compat reasons */ int master_key_length; master_key_length = sizeof(s->session->master_key); if (s->ext.session_secret_cb(s, s->session->master_key, &master_key_length, ciphers, &pref_cipher, s->ext.session_secret_cb_arg) && master_key_length > 0) { s->session->master_key_length = master_key_length; s->hit = 1; s->session->ciphers = ciphers; s->session->verify_result = X509_V_OK; ciphers = NULL; /* check if some cipher was preferred by call back */ if (pref_cipher == NULL) pref_cipher = ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s)); if (pref_cipher == NULL) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_NO_SHARED_CIPHER); goto err; } s->session->cipher = pref_cipher; sk_SSL_CIPHER_free(s->cipher_list); s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers); sk_SSL_CIPHER_free(s->cipher_list_by_id); s->cipher_list_by_id = sk_SSL_CIPHER_dup(s->session->ciphers); } } /* * Worst case, we will use the NULL compression, but if we have other * options, we will now look for them. We have complen-1 compression * algorithms from the client, starting at q. */ s->s3->tmp.new_compression = NULL; if (SSL_IS_TLS13(s)) { /* * We already checked above that the NULL compression method appears in * the list. Now we check there aren't any others (which is illegal in * a TLSv1.3 ClientHello. */ if (clienthello->compressions_len != 1) { SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_INVALID_COMPRESSION_ALGORITHM); goto err; } } #ifndef OPENSSL_NO_COMP /* This only happens if we have a cache hit */ else if (s->session->compress_meth != 0) { int m, comp_id = s->session->compress_meth; unsigned int k; /* Perform sanity checks on resumed compression algorithm */ /* Can't disable compression */ if (!ssl_allow_compression(s)) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_INCONSISTENT_COMPRESSION); goto err; } /* Look for resumed compression method */ for (m = 0; m < sk_SSL_COMP_num(s->ctx->comp_methods); m++) { comp = sk_SSL_COMP_value(s->ctx->comp_methods, m); if (comp_id == comp->id) { s->s3->tmp.new_compression = comp; break; } } if (s->s3->tmp.new_compression == NULL) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_INVALID_COMPRESSION_ALGORITHM); goto err; } /* Look for resumed method in compression list */ for (k = 0; k < clienthello->compressions_len; k++) { if (clienthello->compressions[k] == comp_id) break; } if (k >= clienthello->compressions_len) { SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_REQUIRED_COMPRESSION_ALGORITHM_MISSING); goto err; } } else if (s->hit) { comp = NULL; } else if (ssl_allow_compression(s) && s->ctx->comp_methods) { /* See if we have a match */ int m, nn, v, done = 0; unsigned int o; nn = sk_SSL_COMP_num(s->ctx->comp_methods); for (m = 0; m < nn; m++) { comp = sk_SSL_COMP_value(s->ctx->comp_methods, m); v = comp->id; for (o = 0; o < clienthello->compressions_len; o++) { if (v == clienthello->compressions[o]) { done = 1; break; } } if (done) break; } if (done) s->s3->tmp.new_compression = comp; else comp = NULL; } #else /* * If compression is disabled we'd better not try to resume a session * using compression. */ if (s->session->compress_meth != 0) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, SSL_R_INCONSISTENT_COMPRESSION); goto err; } #endif /* * Given s->session->ciphers and SSL_get_ciphers, we must pick a cipher */ if (!s->hit || SSL_IS_TLS13(s)) { sk_SSL_CIPHER_free(s->session->ciphers); s->session->ciphers = ciphers; if (ciphers == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); goto err; } ciphers = NULL; } if (!s->hit) { #ifdef OPENSSL_NO_COMP s->session->compress_meth = 0; #else s->session->compress_meth = (comp == NULL) ? 0 : comp->id; #endif if (!tls1_set_server_sigalgs(s)) { /* SSLfatal() already called */ goto err; } } sk_SSL_CIPHER_free(ciphers); sk_SSL_CIPHER_free(scsvs); OPENSSL_free(clienthello->pre_proc_exts); OPENSSL_free(s->clienthello); s->clienthello = NULL; return 1; err: sk_SSL_CIPHER_free(ciphers); sk_SSL_CIPHER_free(scsvs); OPENSSL_free(clienthello->pre_proc_exts); OPENSSL_free(s->clienthello); s->clienthello = NULL; return 0; } /* * Call the status request callback if needed. Upon success, returns 1. * Upon failure, returns 0. */ static int tls_handle_status_request(SSL *s) { s->ext.status_expected = 0; /* * If status request then ask callback what to do. Note: this must be * called after servername callbacks in case the certificate has changed, * and must be called after the cipher has been chosen because this may * influence which certificate is sent */ if (s->ext.status_type != TLSEXT_STATUSTYPE_nothing && s->ctx != NULL && s->ctx->ext.status_cb != NULL) { int ret; /* If no certificate can't return certificate status */ if (s->s3->tmp.cert != NULL) { /* * Set current certificate to one we will use so SSL_get_certificate * et al can pick it up. */ s->cert->key = s->s3->tmp.cert; ret = s->ctx->ext.status_cb(s, s->ctx->ext.status_arg); switch (ret) { /* We don't want to send a status request response */ case SSL_TLSEXT_ERR_NOACK: s->ext.status_expected = 0; break; /* status request response should be sent */ case SSL_TLSEXT_ERR_OK: if (s->ext.ocsp.resp) s->ext.status_expected = 1; break; /* something bad happened */ case SSL_TLSEXT_ERR_ALERT_FATAL: default: SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_HANDLE_STATUS_REQUEST, SSL_R_CLIENTHELLO_TLSEXT); return 0; } } } return 1; } /* * Call the alpn_select callback if needed. Upon success, returns 1. * Upon failure, returns 0. */ int tls_handle_alpn(SSL *s) { const unsigned char *selected = NULL; unsigned char selected_len = 0; if (s->ctx->ext.alpn_select_cb != NULL && s->s3->alpn_proposed != NULL) { int r = s->ctx->ext.alpn_select_cb(s, &selected, &selected_len, s->s3->alpn_proposed, (unsigned int)s->s3->alpn_proposed_len, s->ctx->ext.alpn_select_cb_arg); if (r == SSL_TLSEXT_ERR_OK) { OPENSSL_free(s->s3->alpn_selected); s->s3->alpn_selected = OPENSSL_memdup(selected, selected_len); if (s->s3->alpn_selected == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_HANDLE_ALPN, ERR_R_INTERNAL_ERROR); return 0; } s->s3->alpn_selected_len = selected_len; #ifndef OPENSSL_NO_NEXTPROTONEG /* ALPN takes precedence over NPN. */ s->s3->npn_seen = 0; #endif /* Check ALPN is consistent with session */ if (s->session->ext.alpn_selected == NULL || selected_len != s->session->ext.alpn_selected_len || memcmp(selected, s->session->ext.alpn_selected, selected_len) != 0) { /* Not consistent so can't be used for early_data */ s->ext.early_data_ok = 0; if (!s->hit) { /* * This is a new session and so alpn_selected should have * been initialised to NULL. We should update it with the * selected ALPN. */ if (!ossl_assert(s->session->ext.alpn_selected == NULL)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_HANDLE_ALPN, ERR_R_INTERNAL_ERROR); return 0; } s->session->ext.alpn_selected = OPENSSL_memdup(selected, selected_len); if (s->session->ext.alpn_selected == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_HANDLE_ALPN, ERR_R_INTERNAL_ERROR); return 0; } s->session->ext.alpn_selected_len = selected_len; } } return 1; } else if (r != SSL_TLSEXT_ERR_NOACK) { SSLfatal(s, SSL_AD_NO_APPLICATION_PROTOCOL, SSL_F_TLS_HANDLE_ALPN, SSL_R_NO_APPLICATION_PROTOCOL); return 0; } /* * If r == SSL_TLSEXT_ERR_NOACK then behave as if no callback was * present. */ } /* Check ALPN is consistent with session */ if (s->session->ext.alpn_selected != NULL) { /* Not consistent so can't be used for early_data */ s->ext.early_data_ok = 0; } return 1; } WORK_STATE tls_post_process_client_hello(SSL *s, WORK_STATE wst) { const SSL_CIPHER *cipher; if (wst == WORK_MORE_A) { int rv = tls_early_post_process_client_hello(s); if (rv == 0) { /* SSLfatal() was already called */ goto err; } if (rv < 0) return WORK_MORE_A; wst = WORK_MORE_B; } if (wst == WORK_MORE_B) { if (!s->hit || SSL_IS_TLS13(s)) { /* Let cert callback update server certificates if required */ if (!s->hit && s->cert->cert_cb != NULL) { int rv = s->cert->cert_cb(s, s->cert->cert_cb_arg); if (rv == 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_POST_PROCESS_CLIENT_HELLO, SSL_R_CERT_CB_ERROR); goto err; } if (rv < 0) { s->rwstate = SSL_X509_LOOKUP; return WORK_MORE_B; } s->rwstate = SSL_NOTHING; } /* In TLSv1.3 we selected the ciphersuite before resumption */ if (!SSL_IS_TLS13(s)) { cipher = ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s)); if (cipher == NULL) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_POST_PROCESS_CLIENT_HELLO, SSL_R_NO_SHARED_CIPHER); goto err; } s->s3->tmp.new_cipher = cipher; } if (!s->hit) { if (!tls_choose_sigalg(s, 1)) { /* SSLfatal already called */ goto err; } /* check whether we should disable session resumption */ if (s->not_resumable_session_cb != NULL) s->session->not_resumable = s->not_resumable_session_cb(s, ((s->s3->tmp.new_cipher->algorithm_mkey & (SSL_kDHE | SSL_kECDHE)) != 0)); if (s->session->not_resumable) /* do not send a session ticket */ s->ext.ticket_expected = 0; } } else { /* Session-id reuse */ s->s3->tmp.new_cipher = s->session->cipher; } /*- * we now have the following setup. * client_random * cipher_list - our preferred list of ciphers * ciphers - the clients preferred list of ciphers * compression - basically ignored right now * ssl version is set - sslv3 * s->session - The ssl session has been setup. * s->hit - session reuse flag * s->s3->tmp.new_cipher- the new cipher to use. */ /* * Call status_request callback if needed. Has to be done after the * certificate callbacks etc above. */ if (!tls_handle_status_request(s)) { /* SSLfatal() already called */ goto err; } /* * Call alpn_select callback if needed. Has to be done after SNI and * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3 * we already did this because cipher negotiation happens earlier, and * we must handle ALPN before we decide whether to accept early_data. */ if (!SSL_IS_TLS13(s) && !tls_handle_alpn(s)) { /* SSLfatal() already called */ goto err; } wst = WORK_MORE_C; } #ifndef OPENSSL_NO_SRP if (wst == WORK_MORE_C) { int ret; if ((ret = ssl_check_srp_ext_ClientHello(s)) == 0) { /* * callback indicates further work to be done */ s->rwstate = SSL_X509_LOOKUP; return WORK_MORE_C; } if (ret < 0) { /* SSLfatal() already called */ goto err; } } #endif return WORK_FINISHED_STOP; err: return WORK_ERROR; } int tls_construct_server_hello(SSL *s, WPACKET *pkt) { int compm; size_t sl, len; int version; unsigned char *session_id; int usetls13 = SSL_IS_TLS13(s) || s->hello_retry_request == SSL_HRR_PENDING; version = usetls13 ? TLS1_2_VERSION : s->version; if (!WPACKET_put_bytes_u16(pkt, version) /* * Random stuff. Filling of the server_random takes place in * tls_process_client_hello() */ || !WPACKET_memcpy(pkt, s->hello_retry_request == SSL_HRR_PENDING ? hrrrandom : s->s3->server_random, SSL3_RANDOM_SIZE)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_HELLO, ERR_R_INTERNAL_ERROR); return 0; } /*- * There are several cases for the session ID to send * back in the server hello: * - For session reuse from the session cache, * we send back the old session ID. * - If stateless session reuse (using a session ticket) * is successful, we send back the client's "session ID" * (which doesn't actually identify the session). * - If it is a new session, we send back the new * session ID. * - However, if we want the new session to be single-use, * we send back a 0-length session ID. * - In TLSv1.3 we echo back the session id sent to us by the client * regardless * s->hit is non-zero in either case of session reuse, * so the following won't overwrite an ID that we're supposed * to send back. */ if (s->session->not_resumable || (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER) && !s->hit)) s->session->session_id_length = 0; if (usetls13) { sl = s->tmp_session_id_len; session_id = s->tmp_session_id; } else { sl = s->session->session_id_length; session_id = s->session->session_id; } if (sl > sizeof(s->session->session_id)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_HELLO, ERR_R_INTERNAL_ERROR); return 0; } /* set up the compression method */ #ifdef OPENSSL_NO_COMP compm = 0; #else if (usetls13 || s->s3->tmp.new_compression == NULL) compm = 0; else compm = s->s3->tmp.new_compression->id; #endif if (!WPACKET_sub_memcpy_u8(pkt, session_id, sl) || !s->method->put_cipher_by_char(s->s3->tmp.new_cipher, pkt, &len) || !WPACKET_put_bytes_u8(pkt, compm) || !tls_construct_extensions(s, pkt, s->hello_retry_request == SSL_HRR_PENDING ? SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST : (SSL_IS_TLS13(s) ? SSL_EXT_TLS1_3_SERVER_HELLO : SSL_EXT_TLS1_2_SERVER_HELLO), NULL, 0)) { /* SSLfatal() already called */ return 0; } if (s->hello_retry_request == SSL_HRR_PENDING) { /* Ditch the session. We'll create a new one next time around */ SSL_SESSION_free(s->session); s->session = NULL; s->hit = 0; /* * Re-initialise the Transcript Hash. We're going to prepopulate it with * a synthetic message_hash in place of ClientHello1. */ if (!create_synthetic_message_hash(s, NULL, 0, NULL, 0)) { /* SSLfatal() already called */ return 0; } } else if (!(s->verify_mode & SSL_VERIFY_PEER) && !ssl3_digest_cached_records(s, 0)) { /* SSLfatal() already called */; return 0; } return 1; } int tls_construct_server_done(SSL *s, WPACKET *pkt) { if (!s->s3->tmp.cert_request) { if (!ssl3_digest_cached_records(s, 0)) { /* SSLfatal() already called */ return 0; } } return 1; } int tls_construct_server_key_exchange(SSL *s, WPACKET *pkt) { #ifndef OPENSSL_NO_DH EVP_PKEY *pkdh = NULL; #endif #ifndef OPENSSL_NO_EC unsigned char *encodedPoint = NULL; size_t encodedlen = 0; int curve_id = 0; #endif const SIGALG_LOOKUP *lu = s->s3->tmp.sigalg; int i; unsigned long type; const BIGNUM *r[4]; EVP_MD_CTX *md_ctx = EVP_MD_CTX_new(); EVP_PKEY_CTX *pctx = NULL; size_t paramlen, paramoffset; if (!WPACKET_get_total_written(pkt, ¶moffset)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } if (md_ctx == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_MALLOC_FAILURE); goto err; } type = s->s3->tmp.new_cipher->algorithm_mkey; r[0] = r[1] = r[2] = r[3] = NULL; #ifndef OPENSSL_NO_PSK /* Plain PSK or RSAPSK nothing to do */ if (type & (SSL_kPSK | SSL_kRSAPSK)) { } else #endif /* !OPENSSL_NO_PSK */ #ifndef OPENSSL_NO_DH if (type & (SSL_kDHE | SSL_kDHEPSK)) { CERT *cert = s->cert; EVP_PKEY *pkdhp = NULL; DH *dh; if (s->cert->dh_tmp_auto) { DH *dhp = ssl_get_auto_dh(s); pkdh = EVP_PKEY_new(); if (pkdh == NULL || dhp == NULL) { DH_free(dhp); SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } EVP_PKEY_assign_DH(pkdh, dhp); pkdhp = pkdh; } else { pkdhp = cert->dh_tmp; } if ((pkdhp == NULL) && (s->cert->dh_tmp_cb != NULL)) { DH *dhp = s->cert->dh_tmp_cb(s, 0, 1024); pkdh = ssl_dh_to_pkey(dhp); if (pkdh == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } pkdhp = pkdh; } if (pkdhp == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, SSL_R_MISSING_TMP_DH_KEY); goto err; } if (!ssl_security(s, SSL_SECOP_TMP_DH, EVP_PKEY_security_bits(pkdhp), 0, pkdhp)) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, SSL_R_DH_KEY_TOO_SMALL); goto err; } if (s->s3->tmp.pkey != NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } s->s3->tmp.pkey = ssl_generate_pkey(pkdhp); if (s->s3->tmp.pkey == NULL) { /* SSLfatal() already called */ goto err; } dh = EVP_PKEY_get0_DH(s->s3->tmp.pkey); EVP_PKEY_free(pkdh); pkdh = NULL; DH_get0_pqg(dh, &r[0], NULL, &r[1]); DH_get0_key(dh, &r[2], NULL); } else #endif #ifndef OPENSSL_NO_EC if (type & (SSL_kECDHE | SSL_kECDHEPSK)) { if (s->s3->tmp.pkey != NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } /* Get NID of appropriate shared curve */ curve_id = tls1_shared_group(s, -2); if (curve_id == 0) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); goto err; } s->s3->tmp.pkey = ssl_generate_pkey_group(s, curve_id); /* Generate a new key for this curve */ if (s->s3->tmp.pkey == NULL) { /* SSLfatal() already called */ goto err; } /* Encode the public key. */ encodedlen = EVP_PKEY_get1_tls_encodedpoint(s->s3->tmp.pkey, &encodedPoint); if (encodedlen == 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_EC_LIB); goto err; } /* * We'll generate the serverKeyExchange message explicitly so we * can set these to NULLs */ r[0] = NULL; r[1] = NULL; r[2] = NULL; r[3] = NULL; } else #endif /* !OPENSSL_NO_EC */ #ifndef OPENSSL_NO_SRP if (type & SSL_kSRP) { if ((s->srp_ctx.N == NULL) || (s->srp_ctx.g == NULL) || (s->srp_ctx.s == NULL) || (s->srp_ctx.B == NULL)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, SSL_R_MISSING_SRP_PARAM); goto err; } r[0] = s->srp_ctx.N; r[1] = s->srp_ctx.g; r[2] = s->srp_ctx.s; r[3] = s->srp_ctx.B; } else #endif { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE); goto err; } if (((s->s3->tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP)) != 0) || ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_PSK)) != 0) { lu = NULL; } else if (lu == NULL) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } #ifndef OPENSSL_NO_PSK if (type & SSL_PSK) { size_t len = (s->cert->psk_identity_hint == NULL) ? 0 : strlen(s->cert->psk_identity_hint); /* * It should not happen that len > PSK_MAX_IDENTITY_LEN - we already * checked this when we set the identity hint - but just in case */ if (len > PSK_MAX_IDENTITY_LEN || !WPACKET_sub_memcpy_u16(pkt, s->cert->psk_identity_hint, len)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } } #endif for (i = 0; i < 4 && r[i] != NULL; i++) { unsigned char *binval; int res; #ifndef OPENSSL_NO_SRP if ((i == 2) && (type & SSL_kSRP)) { res = WPACKET_start_sub_packet_u8(pkt); } else #endif res = WPACKET_start_sub_packet_u16(pkt); if (!res) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } #ifndef OPENSSL_NO_DH /*- * for interoperability with some versions of the Microsoft TLS * stack, we need to zero pad the DHE pub key to the same length * as the prime */ if ((i == 2) && (type & (SSL_kDHE | SSL_kDHEPSK))) { size_t len = BN_num_bytes(r[0]) - BN_num_bytes(r[2]); if (len > 0) { if (!WPACKET_allocate_bytes(pkt, len, &binval)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } memset(binval, 0, len); } } #endif if (!WPACKET_allocate_bytes(pkt, BN_num_bytes(r[i]), &binval) || !WPACKET_close(pkt)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } BN_bn2bin(r[i], binval); } #ifndef OPENSSL_NO_EC if (type & (SSL_kECDHE | SSL_kECDHEPSK)) { /* * We only support named (not generic) curves. In this situation, the * ServerKeyExchange message has: [1 byte CurveType], [2 byte CurveName] * [1 byte length of encoded point], followed by the actual encoded * point itself */ if (!WPACKET_put_bytes_u8(pkt, NAMED_CURVE_TYPE) || !WPACKET_put_bytes_u8(pkt, 0) || !WPACKET_put_bytes_u8(pkt, curve_id) || !WPACKET_sub_memcpy_u8(pkt, encodedPoint, encodedlen)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } OPENSSL_free(encodedPoint); encodedPoint = NULL; } #endif /* not anonymous */ if (lu != NULL) { EVP_PKEY *pkey = s->s3->tmp.cert->privatekey; const EVP_MD *md; unsigned char *sigbytes1, *sigbytes2, *tbs; size_t siglen, tbslen; int rv; if (pkey == NULL || !tls1_lookup_md(lu, &md)) { /* Should never happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } /* Get length of the parameters we have written above */ if (!WPACKET_get_length(pkt, ¶mlen)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } /* send signature algorithm */ if (SSL_USE_SIGALGS(s) && !WPACKET_put_bytes_u16(pkt, lu->sigalg)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } /* * Create the signature. We don't know the actual length of the sig * until after we've created it, so we reserve enough bytes for it * up front, and then properly allocate them in the WPACKET * afterwards. */ siglen = EVP_PKEY_size(pkey); if (!WPACKET_sub_reserve_bytes_u16(pkt, siglen, &sigbytes1) || EVP_DigestSignInit(md_ctx, &pctx, md, NULL, pkey) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } if (lu->sig == EVP_PKEY_RSA_PSS) { if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0 || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, RSA_PSS_SALTLEN_DIGEST) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_EVP_LIB); goto err; } } tbslen = construct_key_exchange_tbs(s, &tbs, s->init_buf->data + paramoffset, paramlen); if (tbslen == 0) { /* SSLfatal() already called */ goto err; } rv = EVP_DigestSign(md_ctx, sigbytes1, &siglen, tbs, tbslen); OPENSSL_free(tbs); if (rv <= 0 || !WPACKET_sub_allocate_bytes_u16(pkt, siglen, &sigbytes2) || sigbytes1 != sigbytes2) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); goto err; } } EVP_MD_CTX_free(md_ctx); return 1; err: #ifndef OPENSSL_NO_DH EVP_PKEY_free(pkdh); #endif #ifndef OPENSSL_NO_EC OPENSSL_free(encodedPoint); #endif EVP_MD_CTX_free(md_ctx); return 0; } int tls_construct_certificate_request(SSL *s, WPACKET *pkt) { if (SSL_IS_TLS13(s)) { /* Send random context when doing post-handshake auth */ if (s->post_handshake_auth == SSL_PHA_REQUEST_PENDING) { OPENSSL_free(s->pha_context); s->pha_context_len = 32; if ((s->pha_context = OPENSSL_malloc(s->pha_context_len)) == NULL || RAND_bytes(s->pha_context, s->pha_context_len) <= 0 || !WPACKET_sub_memcpy_u8(pkt, s->pha_context, s->pha_context_len)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } /* reset the handshake hash back to just after the ClientFinished */ if (!tls13_restore_handshake_digest_for_pha(s)) { /* SSLfatal() already called */ return 0; } } else { if (!WPACKET_put_bytes_u8(pkt, 0)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } } if (!tls_construct_extensions(s, pkt, SSL_EXT_TLS1_3_CERTIFICATE_REQUEST, NULL, 0)) { /* SSLfatal() already called */ return 0; } goto done; } /* get the list of acceptable cert types */ if (!WPACKET_start_sub_packet_u8(pkt) || !ssl3_get_req_cert_type(s, pkt) || !WPACKET_close(pkt)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } if (SSL_USE_SIGALGS(s)) { const uint16_t *psigs; size_t nl = tls12_get_psigalgs(s, 1, &psigs); if (!WPACKET_start_sub_packet_u16(pkt) || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH) || !tls12_copy_sigalgs(s, pkt, psigs, nl) || !WPACKET_close(pkt)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } } if (!construct_ca_names(s, pkt)) { /* SSLfatal() already called */ return 0; } done: s->certreqs_sent++; s->s3->tmp.cert_request = 1; return 1; } static int tls_process_cke_psk_preamble(SSL *s, PACKET *pkt) { #ifndef OPENSSL_NO_PSK unsigned char psk[PSK_MAX_PSK_LEN]; size_t psklen; PACKET psk_identity; if (!PACKET_get_length_prefixed_2(pkt, &psk_identity)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, SSL_R_LENGTH_MISMATCH); return 0; } if (PACKET_remaining(&psk_identity) > PSK_MAX_IDENTITY_LEN) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, SSL_R_DATA_LENGTH_TOO_LONG); return 0; } if (s->psk_server_callback == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, SSL_R_PSK_NO_SERVER_CB); return 0; } if (!PACKET_strndup(&psk_identity, &s->session->psk_identity)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_INTERNAL_ERROR); return 0; } psklen = s->psk_server_callback(s, s->session->psk_identity, psk, sizeof(psk)); if (psklen > PSK_MAX_PSK_LEN) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_INTERNAL_ERROR); return 0; } else if (psklen == 0) { /* * PSK related to the given identity not found */ SSLfatal(s, SSL_AD_UNKNOWN_PSK_IDENTITY, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, SSL_R_PSK_IDENTITY_NOT_FOUND); return 0; } OPENSSL_free(s->s3->tmp.psk); s->s3->tmp.psk = OPENSSL_memdup(psk, psklen); OPENSSL_cleanse(psk, psklen); if (s->s3->tmp.psk == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_MALLOC_FAILURE); return 0; } s->s3->tmp.psklen = psklen; return 1; #else /* Should never happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_INTERNAL_ERROR); return 0; #endif } static int tls_process_cke_rsa(SSL *s, PACKET *pkt) { #ifndef OPENSSL_NO_RSA unsigned char rand_premaster_secret[SSL_MAX_MASTER_KEY_LENGTH]; int decrypt_len; unsigned char decrypt_good, version_good; size_t j, padding_len; PACKET enc_premaster; RSA *rsa = NULL; unsigned char *rsa_decrypt = NULL; int ret = 0; rsa = EVP_PKEY_get0_RSA(s->cert->pkeys[SSL_PKEY_RSA].privatekey); if (rsa == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA, SSL_R_MISSING_RSA_CERTIFICATE); return 0; } /* SSLv3 and pre-standard DTLS omit the length bytes. */ if (s->version == SSL3_VERSION || s->version == DTLS1_BAD_VER) { enc_premaster = *pkt; } else { if (!PACKET_get_length_prefixed_2(pkt, &enc_premaster) || PACKET_remaining(pkt) != 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_RSA, SSL_R_LENGTH_MISMATCH); return 0; } } /* * We want to be sure that the plaintext buffer size makes it safe to * iterate over the entire size of a premaster secret * (SSL_MAX_MASTER_KEY_LENGTH). Reject overly short RSA keys because * their ciphertext cannot accommodate a premaster secret anyway. */ if (RSA_size(rsa) < SSL_MAX_MASTER_KEY_LENGTH) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA, RSA_R_KEY_SIZE_TOO_SMALL); return 0; } rsa_decrypt = OPENSSL_malloc(RSA_size(rsa)); if (rsa_decrypt == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA, ERR_R_MALLOC_FAILURE); return 0; } /* * We must not leak whether a decryption failure occurs because of * Bleichenbacher's attack on PKCS #1 v1.5 RSA padding (see RFC 2246, * section 7.4.7.1). The code follows that advice of the TLS RFC and * generates a random premaster secret for the case that the decrypt * fails. See https://tools.ietf.org/html/rfc5246#section-7.4.7.1 */ if (RAND_bytes(rand_premaster_secret, sizeof(rand_premaster_secret)) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA, ERR_R_INTERNAL_ERROR); goto err; } /* * Decrypt with no padding. PKCS#1 padding will be removed as part of * the timing-sensitive code below. */ /* TODO(size_t): Convert this function */ decrypt_len = (int)RSA_private_decrypt((int)PACKET_remaining(&enc_premaster), PACKET_data(&enc_premaster), rsa_decrypt, rsa, RSA_NO_PADDING); if (decrypt_len < 0) { SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_F_TLS_PROCESS_CKE_RSA, ERR_R_INTERNAL_ERROR); goto err; } /* Check the padding. See RFC 3447, section 7.2.2. */ /* * The smallest padded premaster is 11 bytes of overhead. Small keys * are publicly invalid, so this may return immediately. This ensures * PS is at least 8 bytes. */ if (decrypt_len < 11 + SSL_MAX_MASTER_KEY_LENGTH) { SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_F_TLS_PROCESS_CKE_RSA, SSL_R_DECRYPTION_FAILED); goto err; } padding_len = decrypt_len - SSL_MAX_MASTER_KEY_LENGTH; decrypt_good = constant_time_eq_int_8(rsa_decrypt[0], 0) & constant_time_eq_int_8(rsa_decrypt[1], 2); for (j = 2; j < padding_len - 1; j++) { decrypt_good &= ~constant_time_is_zero_8(rsa_decrypt[j]); } decrypt_good &= constant_time_is_zero_8(rsa_decrypt[padding_len - 1]); /* * If the version in the decrypted pre-master secret is correct then * version_good will be 0xff, otherwise it'll be zero. The * Klima-Pokorny-Rosa extension of Bleichenbacher's attack * (http://eprint.iacr.org/2003/052/) exploits the version number * check as a "bad version oracle". Thus version checks are done in * constant time and are treated like any other decryption error. */ version_good = constant_time_eq_8(rsa_decrypt[padding_len], (unsigned)(s->client_version >> 8)); version_good &= constant_time_eq_8(rsa_decrypt[padding_len + 1], (unsigned)(s->client_version & 0xff)); /* * The premaster secret must contain the same version number as the * ClientHello to detect version rollback attacks (strangely, the * protocol does not offer such protection for DH ciphersuites). * However, buggy clients exist that send the negotiated protocol * version instead if the server does not support the requested * protocol version. If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such * clients. */ if (s->options & SSL_OP_TLS_ROLLBACK_BUG) { unsigned char workaround_good; workaround_good = constant_time_eq_8(rsa_decrypt[padding_len], (unsigned)(s->version >> 8)); workaround_good &= constant_time_eq_8(rsa_decrypt[padding_len + 1], (unsigned)(s->version & 0xff)); version_good |= workaround_good; } /* * Both decryption and version must be good for decrypt_good to * remain non-zero (0xff). */ decrypt_good &= version_good; /* * Now copy rand_premaster_secret over from p using * decrypt_good_mask. If decryption failed, then p does not * contain valid plaintext, however, a check above guarantees * it is still sufficiently large to read from. */ for (j = 0; j < sizeof(rand_premaster_secret); j++) { rsa_decrypt[padding_len + j] = constant_time_select_8(decrypt_good, rsa_decrypt[padding_len + j], rand_premaster_secret[j]); } if (!ssl_generate_master_secret(s, rsa_decrypt + padding_len, sizeof(rand_premaster_secret), 0)) { /* SSLfatal() already called */ goto err; } ret = 1; err: OPENSSL_free(rsa_decrypt); return ret; #else /* Should never happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA, ERR_R_INTERNAL_ERROR); return 0; #endif } static int tls_process_cke_dhe(SSL *s, PACKET *pkt) { #ifndef OPENSSL_NO_DH EVP_PKEY *skey = NULL; DH *cdh; unsigned int i; BIGNUM *pub_key; const unsigned char *data; EVP_PKEY *ckey = NULL; int ret = 0; if (!PACKET_get_net_2(pkt, &i) || PACKET_remaining(pkt) != i) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_DHE, SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG); goto err; } skey = s->s3->tmp.pkey; if (skey == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE, SSL_R_MISSING_TMP_DH_KEY); goto err; } if (PACKET_remaining(pkt) == 0L) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_DHE, SSL_R_MISSING_TMP_DH_KEY); goto err; } if (!PACKET_get_bytes(pkt, &data, i)) { /* We already checked we have enough data */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE, ERR_R_INTERNAL_ERROR); goto err; } ckey = EVP_PKEY_new(); if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) == 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE, SSL_R_BN_LIB); goto err; } cdh = EVP_PKEY_get0_DH(ckey); pub_key = BN_bin2bn(data, i, NULL); if (pub_key == NULL || !DH_set0_key(cdh, pub_key, NULL)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE, ERR_R_INTERNAL_ERROR); if (pub_key != NULL) BN_free(pub_key); goto err; } if (ssl_derive(s, skey, ckey, 1) == 0) { /* SSLfatal() already called */ goto err; } ret = 1; EVP_PKEY_free(s->s3->tmp.pkey); s->s3->tmp.pkey = NULL; err: EVP_PKEY_free(ckey); return ret; #else /* Should never happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE, ERR_R_INTERNAL_ERROR); return 0; #endif } static int tls_process_cke_ecdhe(SSL *s, PACKET *pkt) { #ifndef OPENSSL_NO_EC EVP_PKEY *skey = s->s3->tmp.pkey; EVP_PKEY *ckey = NULL; int ret = 0; if (PACKET_remaining(pkt) == 0L) { /* We don't support ECDH client auth */ SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_PROCESS_CKE_ECDHE, SSL_R_MISSING_TMP_ECDH_KEY); goto err; } else { unsigned int i; const unsigned char *data; /* * Get client's public key from encoded point in the * ClientKeyExchange message. */ /* Get encoded point length */ if (!PACKET_get_1(pkt, &i) || !PACKET_get_bytes(pkt, &data, i) || PACKET_remaining(pkt) != 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_ECDHE, SSL_R_LENGTH_MISMATCH); goto err; } ckey = EVP_PKEY_new(); if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_ECDHE, ERR_R_EVP_LIB); goto err; } if (EVP_PKEY_set1_tls_encodedpoint(ckey, data, i) == 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_ECDHE, ERR_R_EC_LIB); goto err; } } if (ssl_derive(s, skey, ckey, 1) == 0) { /* SSLfatal() already called */ goto err; } ret = 1; EVP_PKEY_free(s->s3->tmp.pkey); s->s3->tmp.pkey = NULL; err: EVP_PKEY_free(ckey); return ret; #else /* Should never happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_ECDHE, ERR_R_INTERNAL_ERROR); return 0; #endif } static int tls_process_cke_srp(SSL *s, PACKET *pkt) { #ifndef OPENSSL_NO_SRP unsigned int i; const unsigned char *data; if (!PACKET_get_net_2(pkt, &i) || !PACKET_get_bytes(pkt, &data, i)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_SRP, SSL_R_BAD_SRP_A_LENGTH); return 0; } if ((s->srp_ctx.A = BN_bin2bn(data, i, NULL)) == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_SRP, ERR_R_BN_LIB); return 0; } if (BN_ucmp(s->srp_ctx.A, s->srp_ctx.N) >= 0 || BN_is_zero(s->srp_ctx.A)) { SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_CKE_SRP, SSL_R_BAD_SRP_PARAMETERS); return 0; } OPENSSL_free(s->session->srp_username); s->session->srp_username = OPENSSL_strdup(s->srp_ctx.login); if (s->session->srp_username == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_SRP, ERR_R_MALLOC_FAILURE); return 0; } if (!srp_generate_server_master_secret(s)) { /* SSLfatal() already called */ return 0; } return 1; #else /* Should never happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_SRP, ERR_R_INTERNAL_ERROR); return 0; #endif } static int tls_process_cke_gost(SSL *s, PACKET *pkt) { #ifndef OPENSSL_NO_GOST EVP_PKEY_CTX *pkey_ctx; EVP_PKEY *client_pub_pkey = NULL, *pk = NULL; unsigned char premaster_secret[32]; const unsigned char *start; size_t outlen = 32, inlen; unsigned long alg_a; int Ttag, Tclass; long Tlen; size_t sess_key_len; const unsigned char *data; int ret = 0; /* Get our certificate private key */ alg_a = s->s3->tmp.new_cipher->algorithm_auth; if (alg_a & SSL_aGOST12) { /* * New GOST ciphersuites have SSL_aGOST01 bit too */ pk = s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey; if (pk == NULL) { pk = s->cert->pkeys[SSL_PKEY_GOST12_256].privatekey; } if (pk == NULL) { pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey; } } else if (alg_a & SSL_aGOST01) { pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey; } pkey_ctx = EVP_PKEY_CTX_new(pk, NULL); if (pkey_ctx == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_MALLOC_FAILURE); return 0; } if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_INTERNAL_ERROR); return 0; } /* * If client certificate is present and is of the same type, maybe * use it for key exchange. Don't mind errors from * EVP_PKEY_derive_set_peer, because it is completely valid to use a * client certificate for authorization only. */ client_pub_pkey = X509_get0_pubkey(s->session->peer); if (client_pub_pkey) { if (EVP_PKEY_derive_set_peer(pkey_ctx, client_pub_pkey) <= 0) ERR_clear_error(); } /* Decrypt session key */ sess_key_len = PACKET_remaining(pkt); if (!PACKET_get_bytes(pkt, &data, sess_key_len)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_INTERNAL_ERROR); goto err; } /* TODO(size_t): Convert this function */ if (ASN1_get_object((const unsigned char **)&data, &Tlen, &Ttag, &Tclass, (long)sess_key_len) != V_ASN1_CONSTRUCTED || Ttag != V_ASN1_SEQUENCE || Tclass != V_ASN1_UNIVERSAL) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_GOST, SSL_R_DECRYPTION_FAILED); goto err; } start = data; inlen = Tlen; if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, start, inlen) <= 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_GOST, SSL_R_DECRYPTION_FAILED); goto err; } /* Generate master secret */ if (!ssl_generate_master_secret(s, premaster_secret, sizeof(premaster_secret), 0)) { /* SSLfatal() already called */ goto err; } /* Check if pubkey from client certificate was used */ if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2, NULL) > 0) s->statem.no_cert_verify = 1; ret = 1; err: EVP_PKEY_CTX_free(pkey_ctx); return ret; #else /* Should never happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_INTERNAL_ERROR); return 0; #endif } MSG_PROCESS_RETURN tls_process_client_key_exchange(SSL *s, PACKET *pkt) { unsigned long alg_k; alg_k = s->s3->tmp.new_cipher->algorithm_mkey; /* For PSK parse and retrieve identity, obtain PSK key */ if ((alg_k & SSL_PSK) && !tls_process_cke_psk_preamble(s, pkt)) { /* SSLfatal() already called */ goto err; } if (alg_k & SSL_kPSK) { /* Identity extracted earlier: should be nothing left */ if (PACKET_remaining(pkt) != 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_KEY_EXCHANGE, SSL_R_LENGTH_MISMATCH); goto err; } /* PSK handled by ssl_generate_master_secret */ if (!ssl_generate_master_secret(s, NULL, 0, 0)) { /* SSLfatal() already called */ goto err; } } else if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) { if (!tls_process_cke_rsa(s, pkt)) { /* SSLfatal() already called */ goto err; } } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) { if (!tls_process_cke_dhe(s, pkt)) { /* SSLfatal() already called */ goto err; } } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) { if (!tls_process_cke_ecdhe(s, pkt)) { /* SSLfatal() already called */ goto err; } } else if (alg_k & SSL_kSRP) { if (!tls_process_cke_srp(s, pkt)) { /* SSLfatal() already called */ goto err; } } else if (alg_k & SSL_kGOST) { if (!tls_process_cke_gost(s, pkt)) { /* SSLfatal() already called */ goto err; } } else { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_KEY_EXCHANGE, SSL_R_UNKNOWN_CIPHER_TYPE); goto err; } return MSG_PROCESS_CONTINUE_PROCESSING; err: #ifndef OPENSSL_NO_PSK OPENSSL_clear_free(s->s3->tmp.psk, s->s3->tmp.psklen); s->s3->tmp.psk = NULL; #endif return MSG_PROCESS_ERROR; } WORK_STATE tls_post_process_client_key_exchange(SSL *s, WORK_STATE wst) { #ifndef OPENSSL_NO_SCTP if (wst == WORK_MORE_A) { if (SSL_IS_DTLS(s)) { unsigned char sctpauthkey[64]; char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)]; /* * Add new shared key for SCTP-Auth, will be ignored if no SCTP * used. */ memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL, sizeof(DTLS1_SCTP_AUTH_LABEL)); if (SSL_export_keying_material(s, sctpauthkey, sizeof(sctpauthkey), labelbuffer, sizeof(labelbuffer), NULL, 0, 0) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_POST_PROCESS_CLIENT_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); return WORK_ERROR; } BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY, sizeof(sctpauthkey), sctpauthkey); } } #endif if (s->statem.no_cert_verify || !s->session->peer) { /* * No certificate verify or no peer certificate so we no longer need * the handshake_buffer */ if (!ssl3_digest_cached_records(s, 0)) { /* SSLfatal() already called */ return WORK_ERROR; } return WORK_FINISHED_CONTINUE; } else { if (!s->s3->handshake_buffer) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_POST_PROCESS_CLIENT_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); return WORK_ERROR; } /* * For sigalgs freeze the handshake buffer. If we support * extms we've done this already so this is a no-op */ if (!ssl3_digest_cached_records(s, 1)) { /* SSLfatal() already called */ return WORK_ERROR; } } return WORK_FINISHED_CONTINUE; } MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt) { int i; MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR; X509 *x = NULL; unsigned long l; const unsigned char *certstart, *certbytes; STACK_OF(X509) *sk = NULL; PACKET spkt, context; size_t chainidx; SSL_SESSION *new_sess = NULL; if ((sk = sk_X509_new_null()) == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_MALLOC_FAILURE); goto err; } if (SSL_IS_TLS13(s) && (!PACKET_get_length_prefixed_1(pkt, &context) || (s->pha_context == NULL && PACKET_remaining(&context) != 0) || (s->pha_context != NULL && !PACKET_equal(&context, s->pha_context, s->pha_context_len)))) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_INVALID_CONTEXT); goto err; } if (!PACKET_get_length_prefixed_3(pkt, &spkt) || PACKET_remaining(pkt) != 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_LENGTH_MISMATCH); goto err; } for (chainidx = 0; PACKET_remaining(&spkt) > 0; chainidx++) { if (!PACKET_get_net_3(&spkt, &l) || !PACKET_get_bytes(&spkt, &certbytes, l)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_CERT_LENGTH_MISMATCH); goto err; } certstart = certbytes; x = d2i_X509(NULL, (const unsigned char **)&certbytes, l); if (x == NULL) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_ASN1_LIB); goto err; } if (certbytes != (certstart + l)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_CERT_LENGTH_MISMATCH); goto err; } if (SSL_IS_TLS13(s)) { RAW_EXTENSION *rawexts = NULL; PACKET extensions; if (!PACKET_get_length_prefixed_2(&spkt, &extensions)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_BAD_LENGTH); goto err; } if (!tls_collect_extensions(s, &extensions, SSL_EXT_TLS1_3_CERTIFICATE, &rawexts, NULL, chainidx == 0) || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE, rawexts, x, chainidx, PACKET_remaining(&spkt) == 0)) { OPENSSL_free(rawexts); goto err; } OPENSSL_free(rawexts); } if (!sk_X509_push(sk, x)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_MALLOC_FAILURE); goto err; } x = NULL; } if (sk_X509_num(sk) <= 0) { /* TLS does not mind 0 certs returned */ if (s->version == SSL3_VERSION) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_NO_CERTIFICATES_RETURNED); goto err; } /* Fail for TLS only if we required a certificate */ else if ((s->verify_mode & SSL_VERIFY_PEER) && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { SSLfatal(s, SSL_AD_CERTIFICATE_REQUIRED, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); goto err; } /* No client certificate so digest cached records */ if (s->s3->handshake_buffer && !ssl3_digest_cached_records(s, 0)) { /* SSLfatal() already called */ goto err; } } else { EVP_PKEY *pkey; i = ssl_verify_cert_chain(s, sk); if (i <= 0) { SSLfatal(s, ssl_verify_alarm_type(s->verify_result), SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_CERTIFICATE_VERIFY_FAILED); goto err; } if (i > 1) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, i); goto err; } pkey = X509_get0_pubkey(sk_X509_value(sk, 0)); if (pkey == NULL) { SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_UNKNOWN_CERTIFICATE_TYPE); goto err; } } /* * Sessions must be immutable once they go into the session cache. Otherwise * we can get multi-thread problems. Therefore we don't "update" sessions, * we replace them with a duplicate. Here, we need to do this every time * a new certificate is received via post-handshake authentication, as the * session may have already gone into the session cache. */ if (s->post_handshake_auth == SSL_PHA_REQUESTED) { int m = s->session_ctx->session_cache_mode; if ((new_sess = ssl_session_dup(s->session, 0)) == 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_MALLOC_FAILURE); goto err; } if (m & SSL_SESS_CACHE_SERVER) { /* * Remove the old session from the cache. We carry on if this fails */ SSL_CTX_remove_session(s->session_ctx, s->session); } SSL_SESSION_free(s->session); s->session = new_sess; } X509_free(s->session->peer); s->session->peer = sk_X509_shift(sk); s->session->verify_result = s->verify_result; sk_X509_pop_free(s->session->peer_chain, X509_free); s->session->peer_chain = sk; /* * Freeze the handshake buffer. For cert_verify_hash, sizeof(s->cert_verify_hash), &s->cert_verify_hash_len)) { /* SSLfatal() already called */ goto err; } ret = MSG_PROCESS_CONTINUE_READING; err: X509_free(x); sk_X509_pop_free(sk, X509_free); return ret; } int tls_construct_server_certificate(SSL *s, WPACKET *pkt) { CERT_PKEY *cpk = s->s3->tmp.cert; if (cpk == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_CERTIFICATE, ERR_R_INTERNAL_ERROR); return 0; } /* * In TLSv1.3 the certificate chain is always preceded by a 0 length context * for the server Certificate message */ if (SSL_IS_TLS13(s) && !WPACKET_put_bytes_u8(pkt, 0)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_CERTIFICATE, ERR_R_INTERNAL_ERROR); return 0; } if (!ssl3_output_cert_chain(s, pkt, cpk)) { /* SSLfatal() already called */ return 0; } return 1; } int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt) { unsigned char *senc = NULL; EVP_CIPHER_CTX *ctx = NULL; HMAC_CTX *hctx = NULL; unsigned char *p, *encdata1, *encdata2, *macdata1, *macdata2; const unsigned char *const_p; int len, slen_full, slen, lenfinal; SSL_SESSION *sess; unsigned int hlen; SSL_CTX *tctx = s->session_ctx; unsigned char iv[EVP_MAX_IV_LENGTH]; unsigned char key_name[TLSEXT_KEYNAME_LENGTH]; int iv_len; size_t macoffset, macendoffset; union { unsigned char age_add_c[sizeof(uint32_t)]; uint32_t age_add; } age_add_u; if (SSL_IS_TLS13(s)) { if (!ssl_generate_session_id(s, s->session)) { /* SSLfatal() already called */ goto err; } if (RAND_bytes(age_add_u.age_add_c, sizeof(age_add_u)) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); goto err; } s->session->ext.tick_age_add = age_add_u.age_add; /* * ticket_nonce is set to a single 0 byte because we only ever send a * single ticket per connection. IMPORTANT: If we ever support multiple * tickets per connection then this will need to be changed. */ OPENSSL_free(s->session->ext.tick_nonce); s->session->ext.tick_nonce = OPENSSL_zalloc(sizeof(char)); if (s->session->ext.tick_nonce == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE); goto err; } s->session->ext.tick_nonce_len = 1; s->session->time = (long)time(NULL); if (s->s3->alpn_selected != NULL) { OPENSSL_free(s->session->ext.alpn_selected); s->session->ext.alpn_selected = OPENSSL_memdup(s->s3->alpn_selected, s->s3->alpn_selected_len); if (s->session->ext.alpn_selected == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE); goto err; } s->session->ext.alpn_selected_len = s->s3->alpn_selected_len; } s->session->ext.max_early_data = s->max_early_data; } if (tctx->generate_ticket_cb != NULL && tctx->generate_ticket_cb(s, tctx->ticket_cb_data) == 0) goto err; /* get session encoding length */ slen_full = i2d_SSL_SESSION(s->session, NULL); /* * Some length values are 16 bits, so forget it if session is too * long */ if (slen_full == 0 || slen_full > 0xFF00) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); goto err; } senc = OPENSSL_malloc(slen_full); if (senc == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE); goto err; } ctx = EVP_CIPHER_CTX_new(); hctx = HMAC_CTX_new(); if (ctx == NULL || hctx == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE); goto err; } p = senc; if (!i2d_SSL_SESSION(s->session, &p)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); goto err; } /* * create a fresh copy (not shared with other threads) to clean up */ const_p = senc; sess = d2i_SSL_SESSION(NULL, &const_p, slen_full); if (sess == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); goto err; } slen = i2d_SSL_SESSION(sess, NULL); if (slen == 0 || slen > slen_full) { /* shouldn't ever happen */ SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); SSL_SESSION_free(sess); goto err; } p = senc; if (!i2d_SSL_SESSION(sess, &p)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); SSL_SESSION_free(sess); goto err; } SSL_SESSION_free(sess); /* * Initialize HMAC and cipher contexts. If callback present it does * all the work otherwise use generated values from parent ctx. */ if (tctx->ext.ticket_key_cb) { /* if 0 is returned, write an empty ticket */ int ret = tctx->ext.ticket_key_cb(s, key_name, iv, ctx, hctx, 1); if (ret == 0) { /* Put timeout and length */ if (!WPACKET_put_bytes_u32(pkt, 0) || !WPACKET_put_bytes_u16(pkt, 0)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); goto err; } OPENSSL_free(senc); EVP_CIPHER_CTX_free(ctx); HMAC_CTX_free(hctx); return 1; } if (ret < 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, SSL_R_CALLBACK_FAILED); goto err; } iv_len = EVP_CIPHER_CTX_iv_length(ctx); } else { const EVP_CIPHER *cipher = EVP_aes_256_cbc(); iv_len = EVP_CIPHER_iv_length(cipher); if (RAND_bytes(iv, iv_len) <= 0 || !EVP_EncryptInit_ex(ctx, cipher, NULL, tctx->ext.secure->tick_aes_key, iv) || !HMAC_Init_ex(hctx, tctx->ext.secure->tick_hmac_key, sizeof(tctx->ext.secure->tick_hmac_key), EVP_sha256(), NULL)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); goto err; } memcpy(key_name, tctx->ext.tick_key_name, sizeof(tctx->ext.tick_key_name)); } /* * Ticket lifetime hint: For TLSv1.2 this is advisory only and we leave this * unspecified for resumed session (for simplicity). * In TLSv1.3 we reset the "time" field above, and always specify the * timeout. */ if (!WPACKET_put_bytes_u32(pkt, (s->hit && !SSL_IS_TLS13(s)) ? 0 : s->session->timeout) || (SSL_IS_TLS13(s) && (!WPACKET_put_bytes_u32(pkt, age_add_u.age_add) || !WPACKET_sub_memcpy_u8(pkt, s->session->ext.tick_nonce, s->session->ext.tick_nonce_len))) /* Now the actual ticket data */ || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_get_total_written(pkt, &macoffset) /* Output key name */ || !WPACKET_memcpy(pkt, key_name, sizeof(key_name)) /* output IV */ || !WPACKET_memcpy(pkt, iv, iv_len) || !WPACKET_reserve_bytes(pkt, slen + EVP_MAX_BLOCK_LENGTH, &encdata1) /* Encrypt session data */ || !EVP_EncryptUpdate(ctx, encdata1, &len, senc, slen) || !WPACKET_allocate_bytes(pkt, len, &encdata2) || encdata1 != encdata2 || !EVP_EncryptFinal(ctx, encdata1 + len, &lenfinal) || !WPACKET_allocate_bytes(pkt, lenfinal, &encdata2) || encdata1 + len != encdata2 || len + lenfinal > slen + EVP_MAX_BLOCK_LENGTH || !WPACKET_get_total_written(pkt, &macendoffset) || !HMAC_Update(hctx, (unsigned char *)s->init_buf->data + macoffset, macendoffset - macoffset) || !WPACKET_reserve_bytes(pkt, EVP_MAX_MD_SIZE, &macdata1) || !HMAC_Final(hctx, macdata1, &hlen) || hlen > EVP_MAX_MD_SIZE || !WPACKET_allocate_bytes(pkt, hlen, &macdata2) || macdata1 != macdata2 || !WPACKET_close(pkt)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR); goto err; } if (SSL_IS_TLS13(s)) { ssl_update_cache(s, SSL_SESS_CACHE_SERVER); if (!tls_construct_extensions(s, pkt, SSL_EXT_TLS1_3_NEW_SESSION_TICKET, NULL, 0)) { /* SSLfatal() already called */ goto err; } } EVP_CIPHER_CTX_free(ctx); HMAC_CTX_free(hctx); OPENSSL_free(senc); return 1; err: OPENSSL_free(senc); EVP_CIPHER_CTX_free(ctx); HMAC_CTX_free(hctx); return 0; } /* * In TLSv1.3 this is called from the extensions code, otherwise it is used to * create a separate message. Returns 1 on success or 0 on failure. */ int tls_construct_cert_status_body(SSL *s, WPACKET *pkt) { if (!WPACKET_put_bytes_u8(pkt, s->ext.status_type) || !WPACKET_sub_memcpy_u24(pkt, s->ext.ocsp.resp, s->ext.ocsp.resp_len)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_STATUS_BODY, ERR_R_INTERNAL_ERROR); return 0; } return 1; } int tls_construct_cert_status(SSL *s, WPACKET *pkt) { if (!tls_construct_cert_status_body(s, pkt)) { /* SSLfatal() already called */ return 0; } return 1; } #ifndef OPENSSL_NO_NEXTPROTONEG /* * tls_process_next_proto reads a Next Protocol Negotiation handshake message. * It sets the next_proto member in s if found */ MSG_PROCESS_RETURN tls_process_next_proto(SSL *s, PACKET *pkt) { PACKET next_proto, padding; size_t next_proto_len; /*- * The payload looks like: * uint8 proto_len; * uint8 proto[proto_len]; * uint8 padding_len; * uint8 padding[padding_len]; */ if (!PACKET_get_length_prefixed_1(pkt, &next_proto) || !PACKET_get_length_prefixed_1(pkt, &padding) || PACKET_remaining(pkt) > 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_NEXT_PROTO, SSL_R_LENGTH_MISMATCH); return MSG_PROCESS_ERROR; } if (!PACKET_memdup(&next_proto, &s->ext.npn, &next_proto_len)) { s->ext.npn_len = 0; SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_NEXT_PROTO, ERR_R_INTERNAL_ERROR); return MSG_PROCESS_ERROR; } s->ext.npn_len = (unsigned char)next_proto_len; return MSG_PROCESS_CONTINUE_READING; } #endif static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt) { if (!tls_construct_extensions(s, pkt, SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS, NULL, 0)) { /* SSLfatal() already called */ return 0; } return 1; } MSG_PROCESS_RETURN tls_process_end_of_early_data(SSL *s, PACKET *pkt) { if (PACKET_remaining(pkt) != 0) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_END_OF_EARLY_DATA, SSL_R_LENGTH_MISMATCH); return MSG_PROCESS_ERROR; } if (s->early_data_state != SSL_EARLY_DATA_READING && s->early_data_state != SSL_EARLY_DATA_READ_RETRY) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_END_OF_EARLY_DATA, ERR_R_INTERNAL_ERROR); return MSG_PROCESS_ERROR; } /* * EndOfEarlyData signals a key change so the end of the message must be on * a record boundary. */ if (RECORD_LAYER_processed_read_pending(&s->rlayer)) { SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_TLS_PROCESS_END_OF_EARLY_DATA, SSL_R_NOT_ON_RECORD_BOUNDARY); return MSG_PROCESS_ERROR; } s->early_data_state = SSL_EARLY_DATA_FINISHED_READING; if (!s->method->ssl3_enc->change_cipher_state(s, SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_READ)) { /* SSLfatal() already called */ return MSG_PROCESS_ERROR; } return MSG_PROCESS_CONTINUE_READING; }