diff options
Diffstat (limited to 'security/nss/lib/ssl/sslspec.c')
| -rw-r--r-- | security/nss/lib/ssl/sslspec.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/security/nss/lib/ssl/sslspec.c b/security/nss/lib/ssl/sslspec.c new file mode 100644 index 0000000000..c5bedad7a6 --- /dev/null +++ b/security/nss/lib/ssl/sslspec.c @@ -0,0 +1,277 @@ +/* -*- 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); + } +} |