/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ /* * Handling of cipher specs. * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include "ssl.h" #include "sslexp.h" #include "sslimpl.h" #include "sslproto.h" #include "pk11func.h" #include "secitem.h" #include "sslimpl.h" /* Record protection algorithms, indexed by SSL3BulkCipher. * * The |max_records| field (|mr| below) is set to a number that is higher than * recommended in some literature (esp. TLS 1.3) because we currently abort the * connection when this limit is reached and we want to ensure that we only * rarely hit this limit. See bug 1268745 for details. */ #define MR_MAX RECORD_SEQ_MAX /* 2^48-1 */ #define MR_128 (0x5aULL << 28) /* For AES and similar. */ #define MR_LOW (1ULL << 20) /* For weak ciphers. */ /* clang-format off */ static const ssl3BulkCipherDef ssl_bulk_cipher_defs[] = { /* |--------- Lengths ---------| */ /* cipher calg : s : */ /* : e b n */ /* oid short_name mr : c l o */ /* k r o t n */ /* e e i c a c */ /* y t type v k g e */ {cipher_null, ssl_calg_null, 0, 0, type_stream, 0, 0, 0, 0, SEC_OID_NULL_CIPHER, "NULL", MR_MAX}, {cipher_rc4, ssl_calg_rc4, 16,16, type_stream, 0, 0, 0, 0, SEC_OID_RC4, "RC4", MR_LOW}, {cipher_des, ssl_calg_des, 8, 8, type_block, 8, 8, 0, 0, SEC_OID_DES_CBC, "DES-CBC", MR_LOW}, {cipher_3des, ssl_calg_3des, 24,24, type_block, 8, 8, 0, 0, SEC_OID_DES_EDE3_CBC, "3DES-EDE-CBC", MR_LOW}, {cipher_aes_128, ssl_calg_aes, 16,16, type_block, 16,16, 0, 0, SEC_OID_AES_128_CBC, "AES-128", MR_128}, {cipher_aes_256, ssl_calg_aes, 32,32, type_block, 16,16, 0, 0, SEC_OID_AES_256_CBC, "AES-256", MR_128}, {cipher_camellia_128, ssl_calg_camellia, 16,16, type_block, 16,16, 0, 0, SEC_OID_CAMELLIA_128_CBC, "Camellia-128", MR_128}, {cipher_camellia_256, ssl_calg_camellia, 32,32, type_block, 16,16, 0, 0, SEC_OID_CAMELLIA_256_CBC, "Camellia-256", MR_128}, {cipher_seed, ssl_calg_seed, 16,16, type_block, 16,16, 0, 0, SEC_OID_SEED_CBC, "SEED-CBC", MR_128}, {cipher_aes_128_gcm, ssl_calg_aes_gcm, 16,16, type_aead, 4, 0,16, 8, SEC_OID_AES_128_GCM, "AES-128-GCM", MR_128}, {cipher_aes_256_gcm, ssl_calg_aes_gcm, 32,32, type_aead, 4, 0,16, 8, SEC_OID_AES_256_GCM, "AES-256-GCM", MR_128}, {cipher_chacha20, ssl_calg_chacha20, 32,32, type_aead, 12, 0,16, 0, SEC_OID_CHACHA20_POLY1305, "ChaCha20-Poly1305", MR_MAX}, {cipher_missing, ssl_calg_null, 0, 0, type_stream, 0, 0, 0, 0, SEC_OID_UNKNOWN, "missing", 0U}, }; /* clang-format on */ const ssl3BulkCipherDef * ssl_GetBulkCipherDef(const ssl3CipherSuiteDef *suiteDef) { SSL3BulkCipher bulkCipher = suiteDef->bulk_cipher_alg; PORT_Assert(bulkCipher < PR_ARRAY_SIZE(ssl_bulk_cipher_defs)); PORT_Assert(ssl_bulk_cipher_defs[bulkCipher].cipher == bulkCipher); return &ssl_bulk_cipher_defs[bulkCipher]; } /* indexed by SSL3MACAlgorithm */ static const ssl3MACDef ssl_mac_defs[] = { /* pad_size is only used for SSL 3.0 MAC. See RFC 6101 Sec. 5.2.3.1. */ /* mac mmech pad_size mac_size */ { ssl_mac_null, CKM_INVALID_MECHANISM, 0, 0, 0 }, { ssl_mac_md5, CKM_SSL3_MD5_MAC, 48, MD5_LENGTH, SEC_OID_HMAC_MD5 }, { ssl_mac_sha, CKM_SSL3_SHA1_MAC, 40, SHA1_LENGTH, SEC_OID_HMAC_SHA1 }, { ssl_hmac_md5, CKM_MD5_HMAC, 0, MD5_LENGTH, SEC_OID_HMAC_MD5 }, { ssl_hmac_sha, CKM_SHA_1_HMAC, 0, SHA1_LENGTH, SEC_OID_HMAC_SHA1 }, { ssl_hmac_sha256, CKM_SHA256_HMAC, 0, SHA256_LENGTH, SEC_OID_HMAC_SHA256 }, { ssl_mac_aead, CKM_INVALID_MECHANISM, 0, 0, 0 }, { ssl_hmac_sha384, CKM_SHA384_HMAC, 0, SHA384_LENGTH, SEC_OID_HMAC_SHA384 } }; const ssl3MACDef * ssl_GetMacDefByAlg(SSL3MACAlgorithm mac) { /* Cast here for clang: https://bugs.llvm.org/show_bug.cgi?id=16154 */ PORT_Assert((size_t)mac < PR_ARRAY_SIZE(ssl_mac_defs)); PORT_Assert(ssl_mac_defs[mac].mac == mac); return &ssl_mac_defs[mac]; } const ssl3MACDef * ssl_GetMacDef(const sslSocket *ss, const ssl3CipherSuiteDef *suiteDef) { SSL3MACAlgorithm mac = suiteDef->mac_alg; if (ss->version > SSL_LIBRARY_VERSION_3_0) { switch (mac) { case ssl_mac_md5: mac = ssl_hmac_md5; break; case ssl_mac_sha: mac = ssl_hmac_sha; break; default: break; } } return ssl_GetMacDefByAlg(mac); } ssl3CipherSpec * ssl_FindCipherSpecByEpoch(sslSocket *ss, SSLSecretDirection direction, DTLSEpoch epoch) { PRCList *cur_p; for (cur_p = PR_LIST_HEAD(&ss->ssl3.hs.cipherSpecs); cur_p != &ss->ssl3.hs.cipherSpecs; cur_p = PR_NEXT_LINK(cur_p)) { ssl3CipherSpec *spec = (ssl3CipherSpec *)cur_p; if (spec->epoch != epoch) { continue; } if (direction != spec->direction) { continue; } return spec; } return NULL; } ssl3CipherSpec * ssl_CreateCipherSpec(sslSocket *ss, SSLSecretDirection direction) { ssl3CipherSpec *spec = PORT_ZNew(ssl3CipherSpec); if (!spec) { return NULL; } spec->refCt = 1; spec->version = ss->version; spec->direction = direction; spec->recordSizeLimit = MAX_FRAGMENT_LENGTH; SSL_TRC(10, ("%d: SSL[%d]: new %s spec %d ct=%d", SSL_GETPID(), ss->fd, SPEC_DIR(spec), spec, spec->refCt)); return spec; } void ssl_SaveCipherSpec(sslSocket *ss, ssl3CipherSpec *spec) { PR_APPEND_LINK(&spec->link, &ss->ssl3.hs.cipherSpecs); } /* Called from ssl3_InitState. */ /* Caller must hold the SpecWriteLock. */ SECStatus ssl_SetupNullCipherSpec(sslSocket *ss, SSLSecretDirection dir) { ssl3CipherSpec *spec; PORT_Assert(ss->opt.noLocks || ssl_HaveSpecWriteLock(ss)); spec = ssl_CreateCipherSpec(ss, dir); if (!spec) { return SECFailure; } /* Set default versions. This value will be used to generate and send * alerts if a version is not negotiated. These values are overridden when * sending a ClientHello and when a version is negotiated. */ spec->version = SSL_LIBRARY_VERSION_TLS_1_0; spec->recordVersion = IS_DTLS(ss) ? SSL_LIBRARY_VERSION_DTLS_1_0_WIRE : SSL_LIBRARY_VERSION_TLS_1_0; spec->cipherDef = &ssl_bulk_cipher_defs[cipher_null]; PORT_Assert(spec->cipherDef->cipher == cipher_null); spec->macDef = &ssl_mac_defs[ssl_mac_null]; PORT_Assert(spec->macDef->mac == ssl_mac_null); spec->cipher = Null_Cipher; spec->phase = "cleartext"; dtls_InitRecvdRecords(&spec->recvdRecords); ssl_SaveCipherSpec(ss, spec); if (dir == ssl_secret_read) { ss->ssl3.crSpec = spec; } else { ss->ssl3.cwSpec = spec; } return SECSuccess; } void ssl_CipherSpecAddRef(ssl3CipherSpec *spec) { ++spec->refCt; SSL_TRC(10, ("%d: SSL[-]: Increment ref ct for %s spec %d. new ct = %d", SSL_GETPID(), SPEC_DIR(spec), spec, spec->refCt)); } void ssl_DestroyKeyMaterial(ssl3KeyMaterial *keyMaterial) { PK11_FreeSymKey(keyMaterial->key); PK11_FreeSymKey(keyMaterial->macKey); if (keyMaterial->macContext != NULL) { PK11_DestroyContext(keyMaterial->macContext, PR_TRUE); } } static void ssl_FreeCipherSpec(ssl3CipherSpec *spec) { SSL_TRC(10, ("%d: SSL[-]: Freeing %s spec %d. epoch=%d", SSL_GETPID(), SPEC_DIR(spec), spec, spec->epoch)); PR_REMOVE_LINK(&spec->link); /* PORT_Assert( ss->opt.noLocks || ssl_HaveSpecWriteLock(ss)); Don't have ss! */ if (spec->cipherContext) { PK11_DestroyContext(spec->cipherContext, PR_TRUE); } PK11_FreeSymKey(spec->masterSecret); ssl_DestroyKeyMaterial(&spec->keyMaterial); ssl_DestroyMaskingContextInner(spec->maskContext); PORT_ZFree(spec, sizeof(*spec)); } /* This function is never called on a spec which is on the * cipherSpecs list. */ void ssl_CipherSpecRelease(ssl3CipherSpec *spec) { if (!spec) { return; } PORT_Assert(spec->refCt > 0); --spec->refCt; SSL_TRC(10, ("%d: SSL[-]: decrement refct for %s spec %d. epoch=%d new ct = %d", SSL_GETPID(), SPEC_DIR(spec), spec, spec->epoch, spec->refCt)); if (!spec->refCt) { ssl_FreeCipherSpec(spec); } } void ssl_DestroyCipherSpecs(PRCList *list) { while (!PR_CLIST_IS_EMPTY(list)) { ssl3CipherSpec *spec = (ssl3CipherSpec *)PR_LIST_TAIL(list); ssl_FreeCipherSpec(spec); } } void ssl_CipherSpecReleaseByEpoch(sslSocket *ss, SSLSecretDirection dir, DTLSEpoch epoch) { ssl3CipherSpec *spec; SSL_TRC(10, ("%d: SSL[%d]: releasing %s cipher spec for epoch %d", SSL_GETPID(), ss->fd, (dir == ssl_secret_read) ? "read" : "write", epoch)); spec = ssl_FindCipherSpecByEpoch(ss, dir, epoch); if (spec) { ssl_CipherSpecRelease(spec); } }