/* * SSL3 Protocol * * ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is the Netscape security libraries. * * The Initial Developer of the Original Code is * Netscape Communications Corporation. * Portions created by the Initial Developer are Copyright (C) 1994-2000 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Dr Vipul Gupta and * Douglas Stebila , Sun Microsystems Laboratories * Nagendra Modadugu , Google Inc. * * Alternatively, the contents of this file may be used under the terms of * either the GNU General Public License Version 2 or later (the "GPL"), or * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ /* TLS extension code moved here from ssl3ecc.c */ /* $Id: ssl3ext.c,v 1.3 2008/10/06 22:04:15 nelson%bolyard.com Exp $ */ #include "nssrenam.h" #include "nss.h" #include "ssl.h" #include "sslimpl.h" #include "pk11pub.h" #include "blapi.h" #include "prinit.h" static unsigned char key_name[SESS_TICKET_KEY_NAME_LEN]; static PK11SymKey *session_ticket_enc_key_pkcs11 = NULL; static PK11SymKey *session_ticket_mac_key_pkcs11 = NULL; static unsigned char session_ticket_enc_key[32]; static unsigned char session_ticket_mac_key[SHA256_LENGTH]; static PRBool session_ticket_keys_initialized = PR_FALSE; static PRCallOnceType generate_session_keys_once; static PRInt32 ssl3_SendServerNameXtn(sslSocket * ss, PRBool append, PRUint32 maxBytes); static SECStatus ssl3_ParseEncryptedSessionTicket(sslSocket *ss, SECItem *data, EncryptedSessionTicket *enc_session_ticket); static SECStatus ssl3_AppendToItem(SECItem *item, const unsigned char *buf, PRUint32 bytes); static SECStatus ssl3_AppendNumberToItem(SECItem *item, PRUint32 num, PRInt32 lenSize); static SECStatus ssl3_GetSessionTicketKeysPKCS11(sslSocket *ss, PK11SymKey **aes_key, PK11SymKey **mac_key); static SECStatus ssl3_GetSessionTicketKeys(const unsigned char **aes_key, PRUint32 *aes_key_length, const unsigned char **mac_key, PRUint32 *mac_key_length); /* * Write bytes. Using this function means the SECItem structure * cannot be freed. The caller is expected to call this function * on a shallow copy of the structure. */ static SECStatus ssl3_AppendToItem(SECItem *item, const unsigned char *buf, PRUint32 bytes) { if (bytes > item->len) return SECFailure; PORT_Memcpy(item->data, buf, bytes); item->data += bytes; item->len -= bytes; return SECSuccess; } /* * Write a number in network byte order. Using this function means the * SECItem structure cannot be freed. The caller is expected to call * this function on a shallow copy of the structure. */ static SECStatus ssl3_AppendNumberToItem(SECItem *item, PRUint32 num, PRInt32 lenSize) { SECStatus rv; uint8 b[4]; uint8 * p = b; switch (lenSize) { case 4: *p++ = (uint8) (num >> 24); case 3: *p++ = (uint8) (num >> 16); case 2: *p++ = (uint8) (num >> 8); case 1: *p = (uint8) num; } rv = ssl3_AppendToItem(item, &b[0], lenSize); return rv; } static SECStatus ssl3_SessionTicketShutdown(void* appData, void* nssData) { if (session_ticket_enc_key_pkcs11) { PK11_FreeSymKey(session_ticket_enc_key_pkcs11); session_ticket_enc_key_pkcs11 = NULL; } if (session_ticket_mac_key_pkcs11) { PK11_FreeSymKey(session_ticket_mac_key_pkcs11); session_ticket_mac_key_pkcs11 = NULL; } PORT_Memset(&generate_session_keys_once, 0, sizeof(generate_session_keys_once)); return SECSuccess; } static PRStatus ssl3_GenerateSessionTicketKeysPKCS11(void *data) { SECStatus rv; sslSocket *ss = (sslSocket *)data; SECKEYPrivateKey *svrPrivKey = ss->serverCerts[kt_rsa].SERVERKEY; SECKEYPublicKey *svrPubKey = ss->serverCerts[kt_rsa].serverKeyPair->pubKey; if (svrPrivKey == NULL || svrPubKey == NULL) { SSL_DBG(("%d: SSL[%d]: Pub or priv key(s) is NULL.", SSL_GETPID(), ss->fd)); goto loser; } /* Get a copy of the session keys from shared memory. */ PORT_Memcpy(key_name, SESS_TICKET_KEY_NAME_PREFIX, sizeof(SESS_TICKET_KEY_NAME_PREFIX)); if (!ssl_GetSessionTicketKeysPKCS11(svrPrivKey, svrPubKey, ss->pkcs11PinArg, &key_name[SESS_TICKET_KEY_NAME_PREFIX_LEN], &session_ticket_enc_key_pkcs11, &session_ticket_mac_key_pkcs11)) return PR_FAILURE; rv = NSS_RegisterShutdown(ssl3_SessionTicketShutdown, NULL); if (rv != SECSuccess) goto loser; return PR_SUCCESS; loser: ssl3_SessionTicketShutdown(NULL, NULL); return PR_FAILURE; } static SECStatus ssl3_GetSessionTicketKeysPKCS11(sslSocket *ss, PK11SymKey **aes_key, PK11SymKey **mac_key) { if (PR_CallOnceWithArg(&generate_session_keys_once, ssl3_GenerateSessionTicketKeysPKCS11, ss) != PR_SUCCESS) return SECFailure; if (session_ticket_enc_key_pkcs11 == NULL || session_ticket_mac_key_pkcs11 == NULL) return SECFailure; *aes_key = session_ticket_enc_key_pkcs11; *mac_key = session_ticket_mac_key_pkcs11; return SECSuccess; } static PRStatus ssl3_GenerateSessionTicketKeys(void) { PORT_Memcpy(key_name, SESS_TICKET_KEY_NAME_PREFIX, sizeof(SESS_TICKET_KEY_NAME_PREFIX)); if (!ssl_GetSessionTicketKeys(&key_name[SESS_TICKET_KEY_NAME_PREFIX_LEN], session_ticket_enc_key, session_ticket_mac_key)) return PR_FAILURE; session_ticket_keys_initialized = PR_TRUE; return PR_SUCCESS; } static SECStatus ssl3_GetSessionTicketKeys(const unsigned char **aes_key, PRUint32 *aes_key_length, const unsigned char **mac_key, PRUint32 *mac_key_length) { if (PR_CallOnce(&generate_session_keys_once, ssl3_GenerateSessionTicketKeys) != SECSuccess) return SECFailure; if (!session_ticket_keys_initialized) return SECFailure; *aes_key = session_ticket_enc_key; *aes_key_length = sizeof(session_ticket_enc_key); *mac_key = session_ticket_mac_key; *mac_key_length = sizeof(session_ticket_mac_key); return SECSuccess; } /* Table of handlers for received TLS hello extensions, one per extension. * In the second generation, this table will be dynamic, and functions * will be registered here. */ static const ssl3HelloExtensionHandler clientHelloHandlers[] = { { server_name_xtn, &ssl3_HandleServerNameXtn }, #ifdef NSS_ENABLE_ECC { elliptic_curves_xtn, &ssl3_HandleSupportedCurvesXtn }, { ec_point_formats_xtn, &ssl3_HandleSupportedPointFormatsXtn }, #endif { session_ticket_xtn, &ssl3_ServerHandleSessionTicketXtn }, { -1, NULL } }; static const ssl3HelloExtensionHandler serverHelloHandlers[] = { { server_name_xtn, &ssl3_HandleServerNameXtn }, /* TODO: add a handler for ec_point_formats_xtn */ { session_ticket_xtn, &ssl3_ClientHandleSessionTicketXtn }, { -1, NULL } }; /* Table of functions to format TLS hello extensions, one per extension. * This static table is for the formatting of client hello extensions. * The server's table of hello senders is dynamic, in the socket struct, * and sender functions are registered there. */ static const ssl3HelloExtensionSender clientHelloSenders[MAX_EXTENSIONS] = { { server_name_xtn, &ssl3_SendServerNameXtn }, #ifdef NSS_ENABLE_ECC { elliptic_curves_xtn, &ssl3_SendSupportedCurvesXtn }, { ec_point_formats_xtn, &ssl3_SendSupportedPointFormatsXtn }, #else { -1, NULL }, { -1, NULL }, #endif { session_ticket_xtn, ssl3_SendSessionTicketXtn } }; static PRBool arrayContainsExtension(const PRUint16 *array, PRUint32 len, PRUint16 ex_type) { int i; for (i = 0; i < len; i++) { if (ex_type == array[i]) return PR_TRUE; } return PR_FALSE; } PRBool ssl3_ExtensionNegotiated(sslSocket *ss, PRUint16 ex_type) { TLSExtensionData *xtnData = &ss->xtnData; return arrayContainsExtension(xtnData->negotiated, xtnData->numNegotiated, ex_type); } static PRBool ssl3_ClientExtensionAdvertised(sslSocket *ss, PRUint16 ex_type) { TLSExtensionData *xtnData = &ss->xtnData; return arrayContainsExtension(xtnData->advertised, xtnData->numAdvertised, ex_type); } /* Format an SNI extension, using the name from the socket's URL, * unless that name is a dotted decimal string. */ static PRInt32 ssl3_SendServerNameXtn( sslSocket * ss, PRBool append, PRUint32 maxBytes) { PRUint32 len; PRNetAddr netAddr; /* must have a hostname */ if (!ss || !ss->url || !ss->url[0]) return 0; /* must not be an IPv4 or IPv6 address */ if (PR_SUCCESS == PR_StringToNetAddr(ss->url, &netAddr)) { /* is an IP address (v4 or v6) */ return 0; } len = PORT_Strlen(ss->url); if (append && maxBytes >= len + 9) { SECStatus rv; /* extension_type */ rv = ssl3_AppendHandshakeNumber(ss, server_name_xtn, 2); if (rv != SECSuccess) return -1; /* length of extension_data */ rv = ssl3_AppendHandshakeNumber(ss, len + 5, 2); if (rv != SECSuccess) return -1; /* length of server_name_list */ rv = ssl3_AppendHandshakeNumber(ss, len + 3, 2); if (rv != SECSuccess) return -1; /* Name Type (host_name) */ rv = ssl3_AppendHandshake(ss, "\0", 1); if (rv != SECSuccess) return -1; /* HostName (length and value) */ rv = ssl3_AppendHandshakeVariable(ss, (unsigned char *)ss->url, len, 2); if (rv != SECSuccess) return -1; if (!ss->sec.isServer) { TLSExtensionData *xtnData = &ss->xtnData; xtnData->advertised[xtnData->numAdvertised++] = server_name_xtn; } } return len + 9; } /* handle an incoming SNI extension, by ignoring it. */ SECStatus ssl3_HandleServerNameXtn(sslSocket * ss, PRUint16 ex_type, SECItem *data) { /* TODO: if client, should verify extension_data is empty. */ /* TODO: if server, should send empty extension_data. */ /* For now, we ignore this, as if we didn't understand it. :-) */ return SECSuccess; } /* Called by both clients and servers. * Clients sends a filled in session ticket if one is available, and otherwise * sends an empty ticket. Servers always send empty tickets. */ PRInt32 ssl3_SendSessionTicketXtn( sslSocket * ss, PRBool append, PRUint32 maxBytes) { PRInt32 extension_length; NewSessionTicket *session_ticket = NULL; /* Ignore the SessionTicket extension if processing is disabled. */ if (!ss->opt.enableSessionTickets) return 0; /* Empty extension length = extension_type (2-bytes) + * length(extension_data) (2-bytes) */ extension_length = 4; /* If we are a client then send a session ticket if one is availble. * Servers that support the extension and are willing to negotiate the * the extension always respond with an empty extension. */ if (!ss->sec.isServer) { sslSessionID *sid = ss->sec.ci.sid; session_ticket = &sid->u.ssl3.sessionTicket; if (session_ticket->ticket.data) { if (ss->xtnData.ticketTimestampVerified) { extension_length += session_ticket->ticket.len; } else if (!append && (session_ticket->ticket_lifetime_hint == 0 || (session_ticket->ticket_lifetime_hint + session_ticket->received_timestamp > ssl_Time()))) { extension_length += session_ticket->ticket.len; ss->xtnData.ticketTimestampVerified = PR_TRUE; } } } if (append && maxBytes >= extension_length) { SECStatus rv; /* extension_type */ rv = ssl3_AppendHandshakeNumber(ss, session_ticket_xtn, 2); if (rv != SECSuccess) goto loser; if (session_ticket && session_ticket->ticket.data && ss->xtnData.ticketTimestampVerified) { rv = ssl3_AppendHandshakeVariable(ss, session_ticket->ticket.data, session_ticket->ticket.len, 2); ss->xtnData.ticketTimestampVerified = PR_FALSE; } else { rv = ssl3_AppendHandshakeNumber(ss, 0, 2); } if (rv != SECSuccess) goto loser; if (!ss->sec.isServer) { TLSExtensionData *xtnData = &ss->xtnData; xtnData->advertised[xtnData->numAdvertised++] = session_ticket_xtn; } } else if (maxBytes < extension_length) { PORT_Assert(0); return 0; } return extension_length; loser: ss->xtnData.ticketTimestampVerified = PR_FALSE; return -1; } /* * NewSessionTicket * Called from ssl3_HandleFinished */ SECStatus ssl3_SendNewSessionTicket(sslSocket *ss) { int i; SECStatus rv; NewSessionTicket ticket; SECItem plaintext; SECItem plaintext_item = {0, NULL, 0}; SECItem ciphertext = {0, NULL, 0}; PRUint32 ciphertext_length; PRBool ms_is_wrapped; unsigned char wrapped_ms[SSL3_MASTER_SECRET_LENGTH]; SECItem ms_item = {0, NULL, 0}; SSL3KEAType effectiveExchKeyType = ssl_kea_null; PRUint32 padding_length; PRUint32 message_length; PRUint32 cert_length; uint8 length_buf[4]; PRUint32 now; PK11SymKey *aes_key_pkcs11; PK11SymKey *mac_key_pkcs11; const unsigned char *aes_key; const unsigned char *mac_key; PRUint32 aes_key_length; PRUint32 mac_key_length; PRUint64 aes_ctx_buf[MAX_CIPHER_CONTEXT_LLONGS]; AESContext *aes_ctx; CK_MECHANISM_TYPE cipherMech = CKM_AES_CBC; PK11Context *aes_ctx_pkcs11; const SECHashObject *hashObj = NULL; PRUint64 hmac_ctx_buf[MAX_MAC_CONTEXT_LLONGS]; HMACContext *hmac_ctx; CK_MECHANISM_TYPE macMech = CKM_SHA256_HMAC; PK11Context *hmac_ctx_pkcs11; unsigned char computed_mac[TLS_EX_SESS_TICKET_MAC_LENGTH]; unsigned int computed_mac_length; unsigned char iv[AES_BLOCK_SIZE]; SECItem ivItem; CK_MECHANISM_TYPE msWrapMech = 0; /* dummy default value, * must be >= 0 */ SSL_TRC(3, ("%d: SSL3[%d]: send session_ticket handshake", SSL_GETPID(), ss->fd)); PORT_Assert( ss->opt.noLocks || ssl_HaveXmitBufLock(ss)); PORT_Assert( ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss)); ticket.ticket_lifetime_hint = TLS_EX_SESS_TICKET_LIFETIME_HINT; cert_length = (ss->opt.requestCertificate && ss->sec.ci.sid->peerCert) ? 3 + ss->sec.ci.sid->peerCert->derCert.len : 0; /* Get IV and encryption keys */ ivItem.data = iv; ivItem.len = sizeof(iv); rv = PK11_GenerateRandom(iv, sizeof(iv)); if (rv != SECSuccess) goto loser; if (ss->opt.bypassPKCS11) { rv = ssl3_GetSessionTicketKeys(&aes_key, &aes_key_length, &mac_key, &mac_key_length); } else { rv = ssl3_GetSessionTicketKeysPKCS11(ss, &aes_key_pkcs11, &mac_key_pkcs11); } if (rv != SECSuccess) goto loser; if (ss->ssl3.pwSpec->msItem.len && ss->ssl3.pwSpec->msItem.data) { /* The master secret is available unwrapped. */ ms_item.data = ss->ssl3.pwSpec->msItem.data; ms_item.len = ss->ssl3.pwSpec->msItem.len; ms_is_wrapped = PR_FALSE; } else { /* Extract the master secret wrapped. */ sslSessionID sid; PORT_Memset(&sid, 0, sizeof(sslSessionID)); if (ss->ssl3.hs.kea_def->kea == kea_ecdhe_rsa) { effectiveExchKeyType = kt_rsa; } else { effectiveExchKeyType = ss->ssl3.hs.kea_def->exchKeyType; } rv = ssl3_CacheWrappedMasterSecret(ss, &sid, ss->ssl3.pwSpec, effectiveExchKeyType); if (rv == SECSuccess) { if (sid.u.ssl3.keys.wrapped_master_secret_len > sizeof(wrapped_ms)) goto loser; memcpy(wrapped_ms, sid.u.ssl3.keys.wrapped_master_secret, sid.u.ssl3.keys.wrapped_master_secret_len); ms_item.data = wrapped_ms; ms_item.len = sid.u.ssl3.keys.wrapped_master_secret_len; msWrapMech = sid.u.ssl3.masterWrapMech; } else { /* TODO: else send an empty ticket. */ goto loser; } ms_is_wrapped = PR_TRUE; } ciphertext_length = sizeof(PRUint16) /* ticket_version */ + sizeof(SSL3ProtocolVersion) /* ssl_version */ + sizeof(ssl3CipherSuite) /* ciphersuite */ + 1 /* compression */ + 10 /* cipher spec parameters */ + 1 /* SessionTicket.ms_is_wrapped */ + 1 /* effectiveExchKeyType */ + 4 /* msWrapMech */ + 2 /* master_secret.length */ + ms_item.len /* master_secret */ + 1 /* client_auth_type */ + cert_length /* cert */ + sizeof(ticket.ticket_lifetime_hint); padding_length = AES_BLOCK_SIZE - (ciphertext_length % AES_BLOCK_SIZE); ciphertext_length += padding_length; message_length = sizeof(ticket.ticket_lifetime_hint) /* ticket_lifetime_hint */ + 2 /* length field for NewSessionTicket.ticket */ + SESS_TICKET_KEY_NAME_LEN /* key_name */ + AES_BLOCK_SIZE /* iv */ + 2 /* length field for NewSessionTicket.ticket.encrypted_state */ + ciphertext_length /* encrypted_state */ + TLS_EX_SESS_TICKET_MAC_LENGTH; /* mac */ if (SECITEM_AllocItem(NULL, &plaintext_item, ciphertext_length) == NULL) goto loser; plaintext = plaintext_item; /* ticket_version */ rv = ssl3_AppendNumberToItem(&plaintext, TLS_EX_SESS_TICKET_VERSION, sizeof(PRUint16)); if (rv != SECSuccess) goto loser; /* ssl_version */ rv = ssl3_AppendNumberToItem(&plaintext, ss->version, sizeof(SSL3ProtocolVersion)); if (rv != SECSuccess) goto loser; /* ciphersuite */ rv = ssl3_AppendNumberToItem(&plaintext, ss->ssl3.hs.cipher_suite, sizeof(ssl3CipherSuite)); if (rv != SECSuccess) goto loser; /* compression */ rv = ssl3_AppendNumberToItem(&plaintext, ss->ssl3.hs.compression, 1); if (rv != SECSuccess) goto loser; /* cipher spec parameters */ rv = ssl3_AppendNumberToItem(&plaintext, ss->sec.authAlgorithm, 1); if (rv != SECSuccess) goto loser; rv = ssl3_AppendNumberToItem(&plaintext, ss->sec.authKeyBits, 4); if (rv != SECSuccess) goto loser; rv = ssl3_AppendNumberToItem(&plaintext, ss->sec.keaType, 1); if (rv != SECSuccess) goto loser; rv = ssl3_AppendNumberToItem(&plaintext, ss->sec.keaKeyBits, 4); if (rv != SECSuccess) goto loser; /* master_secret */ rv = ssl3_AppendNumberToItem(&plaintext, ms_is_wrapped, 1); if (rv != SECSuccess) goto loser; rv = ssl3_AppendNumberToItem(&plaintext, effectiveExchKeyType, 1); if (rv != SECSuccess) goto loser; rv = ssl3_AppendNumberToItem(&plaintext, msWrapMech, 4); if (rv != SECSuccess) goto loser; rv = ssl3_AppendNumberToItem(&plaintext, ms_item.len, 2); if (rv != SECSuccess) goto loser; rv = ssl3_AppendToItem(&plaintext, ms_item.data, ms_item.len); if (rv != SECSuccess) goto loser; /* client_identity */ if (ss->opt.requestCertificate && ss->sec.ci.sid->peerCert) { rv = ssl3_AppendNumberToItem(&plaintext, CLIENT_AUTH_CERTIFICATE, 1); if (rv != SECSuccess) goto loser; rv = ssl3_AppendNumberToItem(&plaintext, ss->sec.ci.sid->peerCert->derCert.len, 3); if (rv != SECSuccess) goto loser; rv = ssl3_AppendToItem(&plaintext, ss->sec.ci.sid->peerCert->derCert.data, ss->sec.ci.sid->peerCert->derCert.len); if (rv != SECSuccess) goto loser; } else { rv = ssl3_AppendNumberToItem(&plaintext, 0, 1); if (rv != SECSuccess) goto loser; } /* timestamp */ now = ssl_Time(); rv = ssl3_AppendNumberToItem(&plaintext, now, sizeof(ticket.ticket_lifetime_hint)); if (rv != SECSuccess) goto loser; PORT_Assert(plaintext.len == padding_length); for (i = 0; i < padding_length; i++) plaintext.data[i] = (unsigned char)padding_length; if (SECITEM_AllocItem(NULL, &ciphertext, ciphertext_length) == NULL) { rv = SECFailure; goto loser; } /* Generate encrypted portion of ticket. */ if (ss->opt.bypassPKCS11) { aes_ctx = (AESContext *)aes_ctx_buf; rv = AES_InitContext(aes_ctx, aes_key, aes_key_length, iv, NSS_AES_CBC, 1, AES_BLOCK_SIZE); if (rv != SECSuccess) goto loser; rv = AES_Encrypt(aes_ctx, ciphertext.data, &ciphertext.len, ciphertext.len, plaintext_item.data, plaintext_item.len); if (rv != SECSuccess) goto loser; } else { aes_ctx_pkcs11 = PK11_CreateContextBySymKey(cipherMech, CKA_ENCRYPT, aes_key_pkcs11, &ivItem); if (!aes_ctx_pkcs11) goto loser; rv = PK11_CipherOp(aes_ctx_pkcs11, ciphertext.data, (int *)&ciphertext.len, ciphertext.len, plaintext_item.data, plaintext_item.len); PK11_Finalize(aes_ctx_pkcs11); PK11_DestroyContext(aes_ctx_pkcs11, PR_TRUE); if (rv != SECSuccess) goto loser; } /* Convert ciphertext length to network order. */ length_buf[0] = (ciphertext.len >> 8) & 0xff; length_buf[1] = (ciphertext.len ) & 0xff; /* Compute MAC. */ if (ss->opt.bypassPKCS11) { hmac_ctx = (HMACContext *)hmac_ctx_buf; hashObj = HASH_GetRawHashObject(HASH_AlgSHA256); if (HMAC_Init(hmac_ctx, hashObj, mac_key, mac_key_length, PR_FALSE) != SECSuccess) goto loser; HMAC_Begin(hmac_ctx); HMAC_Update(hmac_ctx, key_name, SESS_TICKET_KEY_NAME_LEN); HMAC_Update(hmac_ctx, iv, sizeof(iv)); HMAC_Update(hmac_ctx, (unsigned char *)length_buf, 2); HMAC_Update(hmac_ctx, ciphertext.data, ciphertext.len); HMAC_Finish(hmac_ctx, computed_mac, &computed_mac_length, sizeof(computed_mac)); } else { SECItem macParam; macParam.data = NULL; macParam.len = 0; hmac_ctx_pkcs11 = PK11_CreateContextBySymKey(macMech, CKA_SIGN, mac_key_pkcs11, &macParam); if (!hmac_ctx_pkcs11) goto loser; rv = PK11_DigestBegin(hmac_ctx_pkcs11); rv = PK11_DigestOp(hmac_ctx_pkcs11, key_name, SESS_TICKET_KEY_NAME_LEN); rv = PK11_DigestOp(hmac_ctx_pkcs11, iv, sizeof(iv)); rv = PK11_DigestOp(hmac_ctx_pkcs11, (unsigned char *)length_buf, 2); rv = PK11_DigestOp(hmac_ctx_pkcs11, ciphertext.data, ciphertext.len); rv = PK11_DigestFinal(hmac_ctx_pkcs11, computed_mac, &computed_mac_length, sizeof(computed_mac)); PK11_DestroyContext(hmac_ctx_pkcs11, PR_TRUE); if (rv != SECSuccess) goto loser; } /* Serialize the handshake message. */ rv = ssl3_AppendHandshakeHeader(ss, new_session_ticket, message_length); if (rv != SECSuccess) goto loser; rv = ssl3_AppendHandshakeNumber(ss, ticket.ticket_lifetime_hint, sizeof(ticket.ticket_lifetime_hint)); if (rv != SECSuccess) goto loser; rv = ssl3_AppendHandshakeNumber(ss, message_length - sizeof(ticket.ticket_lifetime_hint) - 2, 2); if (rv != SECSuccess) goto loser; rv = ssl3_AppendHandshake(ss, key_name, SESS_TICKET_KEY_NAME_LEN); if (rv != SECSuccess) goto loser; rv = ssl3_AppendHandshake(ss, iv, sizeof(iv)); if (rv != SECSuccess) goto loser; rv = ssl3_AppendHandshakeVariable(ss, ciphertext.data, ciphertext.len, 2); if (rv != SECSuccess) goto loser; rv = ssl3_AppendHandshake(ss, computed_mac, computed_mac_length); if (rv != SECSuccess) goto loser; loser: if (plaintext_item.data) SECITEM_FreeItem(&plaintext_item, PR_FALSE); if (ciphertext.data) SECITEM_FreeItem(&ciphertext, PR_FALSE); return rv; } /* When a client receives a SessionTicket extension a NewSessionTicket * message is expected during the handshake. */ SECStatus ssl3_ClientHandleSessionTicketXtn(sslSocket *ss, PRUint16 ex_type, SECItem *data) { if (data->len != 0) return SECFailure; /* Keep track of negotiated extensions. */ ss->xtnData.negotiated[ss->xtnData.numNegotiated++] = ex_type; return SECSuccess; } SECStatus ssl3_ServerHandleSessionTicketXtn(sslSocket *ss, PRUint16 ex_type, SECItem *data) { SECStatus rv; SECItem *decrypted_state = NULL; SessionTicket *parsed_session_ticket = NULL; sslSessionID *sid = NULL; SSL3Statistics *ssl3stats; /* Ignore the SessionTicket extension if processing is disabled. */ if (!ss->opt.enableSessionTickets) return SECSuccess; /* Keep track of negotiated extensions. */ ss->xtnData.negotiated[ss->xtnData.numNegotiated++] = ex_type; /* Parse the received ticket sent in by the client. We are * lenient about some parse errors, falling back to a fullshake * instead of terminating the current connection. */ if (data->len == 0) { ss->xtnData.emptySessionTicket = PR_TRUE; } else { int i; SECItem extension_data; EncryptedSessionTicket enc_session_ticket; unsigned char computed_mac[TLS_EX_SESS_TICKET_MAC_LENGTH]; unsigned int computed_mac_length; const SECHashObject *hashObj; const unsigned char *aes_key; const unsigned char *mac_key; PK11SymKey *aes_key_pkcs11; PK11SymKey *mac_key_pkcs11; PRUint32 aes_key_length; PRUint32 mac_key_length; PRUint64 hmac_ctx_buf[MAX_MAC_CONTEXT_LLONGS]; HMACContext *hmac_ctx; PK11Context *hmac_ctx_pkcs11; CK_MECHANISM_TYPE macMech = CKM_SHA256_HMAC; PRUint64 aes_ctx_buf[MAX_CIPHER_CONTEXT_LLONGS]; AESContext *aes_ctx; PK11Context *aes_ctx_pkcs11; CK_MECHANISM_TYPE cipherMech = CKM_AES_CBC; unsigned char * padding; PRUint32 padding_length; unsigned char *buffer; unsigned int buffer_len; PRInt32 temp; SECItem cert_item; /* Turn off stateless session resumption if the client sends a * SessionTicket extension, even if the extension turns out to be * malformed (ss->sec.ci.sid is non-NULL when doing session * renegotiation.) */ if (ss->sec.ci.sid != NULL) { ss->sec.uncache(ss->sec.ci.sid); ssl_FreeSID(ss->sec.ci.sid); ss->sec.ci.sid = NULL; } extension_data.data = data->data; /* Keep a copy for future use. */ extension_data.len = data->len; if (ssl3_ParseEncryptedSessionTicket(ss, data, &enc_session_ticket) != SECSuccess) return SECFailure; /* Get session ticket keys. */ if (ss->opt.bypassPKCS11) { rv = ssl3_GetSessionTicketKeys(&aes_key, &aes_key_length, &mac_key, &mac_key_length); } else { rv = ssl3_GetSessionTicketKeysPKCS11(ss, &aes_key_pkcs11, &mac_key_pkcs11); } if (rv != SECSuccess) { SSL_DBG(("%d: SSL[%d]: Unable to get/generate session ticket keys.", SSL_GETPID(), ss->fd)); goto loser; } /* If the ticket sent by the client was generated under a key different * from the one we have, bypass ticket processing. */ if (PORT_Memcmp(enc_session_ticket.key_name, key_name, SESS_TICKET_KEY_NAME_LEN) != 0) { SSL_DBG(("%d: SSL[%d]: Session ticket key_name sent mismatch.", SSL_GETPID(), ss->fd)); goto no_ticket; } /* Verify the MAC on the ticket. MAC verification may also * fail if the MAC key has been recently refreshed. */ if (ss->opt.bypassPKCS11) { hmac_ctx = (HMACContext *)hmac_ctx_buf; hashObj = HASH_GetRawHashObject(HASH_AlgSHA256); if (HMAC_Init(hmac_ctx, hashObj, mac_key, sizeof(session_ticket_mac_key), PR_FALSE) != SECSuccess) goto no_ticket; HMAC_Begin(hmac_ctx); HMAC_Update(hmac_ctx, extension_data.data, extension_data.len - TLS_EX_SESS_TICKET_MAC_LENGTH); if (HMAC_Finish(hmac_ctx, computed_mac, &computed_mac_length, sizeof(computed_mac)) != SECSuccess) goto no_ticket; } else { SECItem macParam; macParam.data = NULL; macParam.len = 0; hmac_ctx_pkcs11 = PK11_CreateContextBySymKey(macMech, CKA_SIGN, mac_key_pkcs11, &macParam); if (!hmac_ctx_pkcs11) { SSL_DBG(("%d: SSL[%d]: Unable to create HMAC context: %d.", SSL_GETPID(), ss->fd, PORT_GetError())); goto no_ticket; } else { SSL_DBG(("%d: SSL[%d]: Successfully created HMAC context.", SSL_GETPID(), ss->fd)); } rv = PK11_DigestBegin(hmac_ctx_pkcs11); rv = PK11_DigestOp(hmac_ctx_pkcs11, extension_data.data, extension_data.len - TLS_EX_SESS_TICKET_MAC_LENGTH); if (rv != SECSuccess) { PK11_DestroyContext(hmac_ctx_pkcs11, PR_TRUE); goto no_ticket; } rv = PK11_DigestFinal(hmac_ctx_pkcs11, computed_mac, &computed_mac_length, sizeof(computed_mac)); PK11_DestroyContext(hmac_ctx_pkcs11, PR_TRUE); if (rv != SECSuccess) goto no_ticket; } if (PORT_Memcmp(computed_mac, enc_session_ticket.mac, computed_mac_length) != 0) { SSL_DBG(("%d: SSL[%d]: Session ticket MAC mismatch.", SSL_GETPID(), ss->fd)); goto no_ticket; } /* We ignore key_name for now. * This is ok as MAC verification succeeded. */ /* Decrypt the ticket. */ /* Plaintext is shorter than the ciphertext due to padding. */ decrypted_state = SECITEM_AllocItem(NULL, NULL, enc_session_ticket.encrypted_state.len); if (ss->opt.bypassPKCS11) { aes_ctx = (AESContext *)aes_ctx_buf; rv = AES_InitContext(aes_ctx, aes_key, sizeof(session_ticket_enc_key), enc_session_ticket.iv, NSS_AES_CBC, 0,AES_BLOCK_SIZE); if (rv != SECSuccess) { SSL_DBG(("%d: SSL[%d]: Unable to create AES context.", SSL_GETPID(), ss->fd)); goto no_ticket; } rv = AES_Decrypt(aes_ctx, decrypted_state->data, &decrypted_state->len, decrypted_state->len, enc_session_ticket.encrypted_state.data, enc_session_ticket.encrypted_state.len); if (rv != SECSuccess) goto no_ticket; } else { SECItem ivItem; ivItem.data = enc_session_ticket.iv; ivItem.len = AES_BLOCK_SIZE; aes_ctx_pkcs11 = PK11_CreateContextBySymKey(cipherMech, CKA_DECRYPT, aes_key_pkcs11, &ivItem); if (!aes_ctx_pkcs11) { SSL_DBG(("%d: SSL[%d]: Unable to create AES context.", SSL_GETPID(), ss->fd)); goto no_ticket; } rv = PK11_CipherOp(aes_ctx_pkcs11, decrypted_state->data, (int *)&decrypted_state->len, decrypted_state->len, enc_session_ticket.encrypted_state.data, enc_session_ticket.encrypted_state.len); PK11_Finalize(aes_ctx_pkcs11); PK11_DestroyContext(aes_ctx_pkcs11, PR_TRUE); if (rv != SECSuccess) goto no_ticket; } /* Check padding. */ padding_length = (PRUint32)decrypted_state->data[decrypted_state->len - 1]; if (padding_length == 0 || padding_length > AES_BLOCK_SIZE) goto no_ticket; padding = &decrypted_state->data[decrypted_state->len - padding_length]; for (i = 0; i < padding_length; i++, padding++) { if (padding_length != (PRUint32)*padding) goto no_ticket; } /* Deserialize session state. */ buffer = decrypted_state->data; buffer_len = decrypted_state->len; parsed_session_ticket = PORT_ZAlloc(sizeof(SessionTicket)); if (parsed_session_ticket == NULL) { rv = SECFailure; goto loser; } /* Read ticket_version (which is ignored for now.) */ temp = ssl3_ConsumeHandshakeNumber(ss, 2, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->ticket_version = (SSL3ProtocolVersion)temp; /* Read SSLVersion. */ temp = ssl3_ConsumeHandshakeNumber(ss, 2, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->ssl_version = (SSL3ProtocolVersion)temp; /* Read cipher_suite. */ temp = ssl3_ConsumeHandshakeNumber(ss, 2, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->cipher_suite = (ssl3CipherSuite)temp; /* Read compression_method. */ temp = ssl3_ConsumeHandshakeNumber(ss, 1, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->compression_method = (SSL3CompressionMethod)temp; /* Read cipher spec parameters. */ temp = ssl3_ConsumeHandshakeNumber(ss, 1, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->authAlgorithm = (SSLSignType)temp; temp = ssl3_ConsumeHandshakeNumber(ss, 4, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->authKeyBits = (PRUint32)temp; temp = ssl3_ConsumeHandshakeNumber(ss, 1, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->keaType = (SSLKEAType)temp; temp = ssl3_ConsumeHandshakeNumber(ss, 4, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->keaKeyBits = (PRUint32)temp; /* Read wrapped master_secret. */ temp = ssl3_ConsumeHandshakeNumber(ss, 1, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->ms_is_wrapped = (PRBool)temp; temp = ssl3_ConsumeHandshakeNumber(ss, 1, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->exchKeyType = (SSL3KEAType)temp; temp = ssl3_ConsumeHandshakeNumber(ss, 4, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->msWrapMech = (CK_MECHANISM_TYPE)temp; temp = ssl3_ConsumeHandshakeNumber(ss, 2, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->ms_length = (PRUint16)temp; if (parsed_session_ticket->ms_length == 0 || /* sanity check MS. */ parsed_session_ticket->ms_length > sizeof(parsed_session_ticket->master_secret)) goto no_ticket; /* Allow for the wrapped master secret to be longer. */ if (buffer_len < sizeof(SSL3_MASTER_SECRET_LENGTH)) goto no_ticket; PORT_Memcpy(parsed_session_ticket->master_secret, buffer, parsed_session_ticket->ms_length); buffer += parsed_session_ticket->ms_length; buffer_len -= parsed_session_ticket->ms_length; /* Read client_identity */ temp = ssl3_ConsumeHandshakeNumber(ss, 1, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->client_identity.client_auth_type = (ClientAuthenticationType)temp; switch(parsed_session_ticket->client_identity.client_auth_type) { case CLIENT_AUTH_ANONYMOUS: break; case CLIENT_AUTH_CERTIFICATE: rv = ssl3_ConsumeHandshakeVariable(ss, &cert_item, 3, &buffer, &buffer_len); if (rv != SECSuccess) goto no_ticket; rv = SECITEM_CopyItem(NULL, &parsed_session_ticket->peer_cert, &cert_item); if (rv != SECSuccess) goto no_ticket; break; default: goto no_ticket; } /* Read timestamp. */ temp = ssl3_ConsumeHandshakeNumber(ss, 4, &buffer, &buffer_len); if (temp < 0) goto no_ticket; parsed_session_ticket->timestamp = (PRUint32)temp; /* Done parsing. Check that all bytes have been consumed. */ if (buffer_len != padding_length) goto no_ticket; /* Use the ticket if it has not expired, otherwise free the allocated * memory since the ticket is of no use. */ if (parsed_session_ticket->timestamp != 0 && parsed_session_ticket->timestamp + TLS_EX_SESS_TICKET_LIFETIME_HINT > ssl_Time()) { sid = ssl3_NewSessionID(ss, PR_TRUE); if (sid == NULL) { rv = SECFailure; goto loser; } /* Copy over parameters. */ sid->version = parsed_session_ticket->ssl_version; sid->u.ssl3.cipherSuite = parsed_session_ticket->cipher_suite; sid->u.ssl3.compression = parsed_session_ticket->compression_method; sid->authAlgorithm = parsed_session_ticket->authAlgorithm; sid->authKeyBits = parsed_session_ticket->authKeyBits; sid->keaType = parsed_session_ticket->keaType; sid->keaKeyBits = parsed_session_ticket->keaKeyBits; /* Copy master secret. */ if (ss->opt.bypassPKCS11 && parsed_session_ticket->ms_is_wrapped) goto no_ticket; if (parsed_session_ticket->ms_length > sizeof(sid->u.ssl3.keys.wrapped_master_secret)) goto no_ticket; PORT_Memcpy(sid->u.ssl3.keys.wrapped_master_secret, parsed_session_ticket->master_secret, parsed_session_ticket->ms_length); sid->u.ssl3.keys.wrapped_master_secret_len = parsed_session_ticket->ms_length; sid->u.ssl3.exchKeyType = parsed_session_ticket->exchKeyType; sid->u.ssl3.masterWrapMech = parsed_session_ticket->msWrapMech; sid->u.ssl3.keys.msIsWrapped = parsed_session_ticket->ms_is_wrapped; sid->u.ssl3.masterValid = PR_TRUE; sid->u.ssl3.keys.resumable = PR_TRUE; /* Copy over client cert from session ticket if there is one. */ if (parsed_session_ticket->peer_cert.data != NULL) { if (sid->peerCert != NULL) CERT_DestroyCertificate(sid->peerCert); sid->peerCert = CERT_NewTempCertificate(ss->dbHandle, &parsed_session_ticket->peer_cert, NULL, PR_FALSE, PR_TRUE); if (sid->peerCert == NULL) { rv = SECFailure; goto loser; } } ss->statelessResume = PR_TRUE; ss->sec.ci.sid = sid; } } if (0) { no_ticket: SSL_DBG(("%d: SSL[%d]: Session ticket parsing failed.", SSL_GETPID(), ss->fd)); ssl3stats = SSL_GetStatistics(); SSL_AtomicIncrementLong(& ssl3stats->hch_sid_ticket_parse_failures ); if (sid) { ssl_FreeSID(sid); sid = NULL; } } rv = SECSuccess; loser: if (decrypted_state != NULL) { SECITEM_FreeItem(decrypted_state, PR_TRUE); decrypted_state = NULL; } if (parsed_session_ticket != NULL) { if (parsed_session_ticket->peer_cert.data) { SECITEM_FreeItem(&parsed_session_ticket->peer_cert, PR_FALSE); } PORT_ZFree(parsed_session_ticket, sizeof(SessionTicket)); } return rv; } /* * Read bytes. Using this function means the SECItem structure * cannot be freed. The caller is expected to call this function * on a shallow copy of the structure. */ static SECStatus ssl3_ConsumeFromItem(SECItem *item, unsigned char **buf, PRUint32 bytes) { if (bytes > item->len) return SECFailure; *buf = item->data; item->data += bytes; item->len -= bytes; return SECSuccess; } static SECStatus ssl3_ParseEncryptedSessionTicket(sslSocket *ss, SECItem *data, EncryptedSessionTicket *enc_session_ticket) { if (ssl3_ConsumeFromItem(data, &enc_session_ticket->key_name, SESS_TICKET_KEY_NAME_LEN) != SECSuccess) return SECFailure; if (ssl3_ConsumeFromItem(data, &enc_session_ticket->iv, AES_BLOCK_SIZE) != SECSuccess) return SECFailure; if (ssl3_ConsumeHandshakeVariable(ss, &enc_session_ticket->encrypted_state, 2, &data->data, &data->len) != SECSuccess) return SECFailure; if (ssl3_ConsumeFromItem(data, &enc_session_ticket->mac, TLS_EX_SESS_TICKET_MAC_LENGTH) != SECSuccess) return SECFailure; if (data->len != 0) /* Make sure that we have consumed all bytes. */ return SECFailure; return SECSuccess; } /* go through hello extensions in buffer "b". * For each one, find the extension handler in the table, and * if present, invoke that handler. * Servers ignore any extensions with unknown extension types. * Clients reject any extensions with unadvertised extension types. */ SECStatus ssl3_HandleHelloExtensions(sslSocket *ss, SSL3Opaque **b, PRUint32 *length) { const ssl3HelloExtensionHandler * handlers = ss->sec.isServer ? clientHelloHandlers : serverHelloHandlers; while (*length) { const ssl3HelloExtensionHandler * handler; SECStatus rv; PRInt32 extension_type; SECItem extension_data; /* Get the extension's type field */ extension_type = ssl3_ConsumeHandshakeNumber(ss, 2, b, length); if (extension_type < 0) /* failure to decode extension_type */ return SECFailure; /* alert already sent */ /* get the data for this extension, so we can pass it or skip it. */ rv = ssl3_ConsumeHandshakeVariable(ss, &extension_data, 2, b, length); if (rv != SECSuccess) return rv; /* Check whether the server sent an extension which was not advertised * in the ClientHello. */ if (!ss->sec.isServer && !ssl3_ClientExtensionAdvertised(ss, extension_type)) return SECFailure; /* TODO: send unsupported_extension alert */ /* Check whether an extension has been sent multiple times. */ if (ssl3_ExtensionNegotiated(ss, extension_type)) return SECFailure; /* find extension_type in table of Hello Extension Handlers */ for (handler = handlers; handler->ex_type >= 0; handler++) { /* if found, call this handler */ if (handler->ex_type == extension_type) { rv = (*handler->ex_handler)(ss, (PRUint16)extension_type, &extension_data); /* Ignore this result */ /* Treat all bad extensions as unrecognized types. */ break; } } } return SECSuccess; } /* Add a callback function to the table of senders of server hello extensions. */ SECStatus ssl3_RegisterServerHelloExtensionSender(sslSocket *ss, PRUint16 ex_type, ssl3HelloExtensionSenderFunc cb) { int i; ssl3HelloExtensionSender *sender = &ss->xtnData.serverSenders[0]; for (i = 0; i < MAX_EXTENSIONS; ++i, ++sender) { if (!sender->ex_sender) { sender->ex_type = ex_type; sender->ex_sender = cb; return SECSuccess; } /* detect duplicate senders */ PORT_Assert(sender->ex_type != ex_type); if (sender->ex_type == ex_type) { /* duplicate */ break; } } PORT_Assert(i < MAX_EXTENSIONS); /* table needs to grow */ PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); return SECFailure; } /* call each of the extension senders and return the accumulated length */ PRInt32 ssl3_CallHelloExtensionSenders(sslSocket *ss, PRBool append, PRUint32 maxBytes, const ssl3HelloExtensionSender *sender) { PRInt32 total_exten_len = 0; int i; if (!sender) sender = &clientHelloSenders[0]; for (i = 0; i < MAX_EXTENSIONS; ++i, ++sender) { if (sender->ex_sender) { PRInt32 extLen = (*sender->ex_sender)(ss, append, maxBytes); if (extLen < 0) return -1; maxBytes -= extLen; total_exten_len += extLen; } } return total_exten_len; }