+/*
+ * Copyright (c) 1999-2001,2005-2014 Apple Inc. All Rights Reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+/*
+ * cipherSpecs.c - SSLCipherSpec declarations
+ */
+
+#include "sslBuildFlags.h"
+#include "sslContext.h"
+#include "sslCipherSpecs.h"
+#include "sslDebug.h"
+#include "sslMemory.h"
+#include "sslDebug.h"
+#include "sslUtils.h"
+#include "sslPriv.h"
+
+#include <tls_handshake.h>
+
+#include <string.h>
+#include <assert.h>
+#include <Security/SecBase.h>
+
+#include <TargetConditionals.h>
+
+
+/* SecureTransport needs it's own copy of KnownCipherSuites for now, there is a copy in coreTLS,
+ that is exported, but it actually should only included the "default" not the supported */
+
+#define ENABLE_ECDH 1
+#define ENABLE_AES_GCM 0
+#define ENABLE_PSK 1
+
+static const uint16_t STKnownCipherSuites[] = {
+#if ENABLE_AES_GCM
+ TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
+ TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
+#endif
+ TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
+ TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
+ TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
+ TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
+ TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA,
+#if ENABLE_AES_GCM
+ TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
+ TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+#endif
+ TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
+ TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+ TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
+ TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
+ TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
+#if ENABLE_ECDH
+#if ENABLE_AES_GCM
+ TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384,
+ TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256,
+#endif
+ TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384,
+ TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256,
+ TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA,
+ TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA,
+ TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
+#if ENABLE_AES_GCM
+ TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384,
+ TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256,
+#endif
+ TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384,
+ TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256,
+ TLS_ECDH_RSA_WITH_AES_256_CBC_SHA,
+ TLS_ECDH_RSA_WITH_AES_128_CBC_SHA,
+ TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA,
+#endif
+
+#if ENABLE_AES_GCM
+ TLS_DHE_RSA_WITH_AES_256_GCM_SHA384,
+ TLS_DHE_RSA_WITH_AES_128_GCM_SHA256,
+#endif // ENABLE_AES_GCM
+ TLS_DHE_RSA_WITH_AES_256_CBC_SHA256,
+ TLS_DHE_RSA_WITH_AES_128_CBC_SHA256,
+ TLS_DHE_RSA_WITH_AES_256_CBC_SHA,
+ TLS_DHE_RSA_WITH_AES_128_CBC_SHA,
+ SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA,
+
+#if ENABLE_AES_GCM
+ TLS_RSA_WITH_AES_256_GCM_SHA384,
+ TLS_RSA_WITH_AES_128_GCM_SHA256,
+#endif
+ TLS_RSA_WITH_AES_256_CBC_SHA256,
+ TLS_RSA_WITH_AES_128_CBC_SHA256,
+ TLS_RSA_WITH_AES_256_CBC_SHA,
+ TLS_RSA_WITH_AES_128_CBC_SHA,
+ SSL_RSA_WITH_3DES_EDE_CBC_SHA,
+
+#if ENABLE_RC4
+ TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
+ TLS_ECDHE_RSA_WITH_RC4_128_SHA,
+ TLS_ECDH_ECDSA_WITH_RC4_128_SHA,
+ TLS_ECDH_RSA_WITH_RC4_128_SHA,
+ SSL_RSA_WITH_RC4_128_SHA,
+ SSL_RSA_WITH_RC4_128_MD5,
+#endif
+
+
+ /* Unsafe ciphersuites */
+
+#if ENABLE_AES_GCM
+ TLS_DH_anon_WITH_AES_256_GCM_SHA384,
+ TLS_DH_anon_WITH_AES_128_GCM_SHA256,
+#endif
+ TLS_DH_anon_WITH_AES_128_CBC_SHA256,
+ TLS_DH_anon_WITH_AES_256_CBC_SHA256,
+ TLS_DH_anon_WITH_AES_128_CBC_SHA,
+ TLS_DH_anon_WITH_AES_256_CBC_SHA,
+ SSL_DH_anon_WITH_RC4_128_MD5,
+ SSL_DH_anon_WITH_3DES_EDE_CBC_SHA,
+
+ TLS_ECDHE_ECDSA_WITH_NULL_SHA,
+ TLS_ECDHE_RSA_WITH_NULL_SHA,
+#if ENABLE_ECDH
+ TLS_ECDH_ECDSA_WITH_NULL_SHA,
+ TLS_ECDH_RSA_WITH_NULL_SHA,
+#endif
+
+#if ENABLE_PSK
+ TLS_PSK_WITH_AES_256_CBC_SHA384,
+ TLS_PSK_WITH_AES_128_CBC_SHA256,
+ TLS_PSK_WITH_AES_256_CBC_SHA,
+ TLS_PSK_WITH_AES_128_CBC_SHA,
+ TLS_PSK_WITH_RC4_128_SHA,
+ TLS_PSK_WITH_3DES_EDE_CBC_SHA,
+ TLS_PSK_WITH_NULL_SHA384,
+ TLS_PSK_WITH_NULL_SHA256,
+ TLS_PSK_WITH_NULL_SHA,
+#endif
+
+ TLS_RSA_WITH_NULL_SHA256,
+ SSL_RSA_WITH_NULL_SHA,
+ SSL_RSA_WITH_NULL_MD5
+
+};
+
+static const unsigned STCipherSuiteCount = sizeof(STKnownCipherSuites)/sizeof(STKnownCipherSuites[0]);
+
+
+/*
+ * Build ctx->validCipherSpecs as a copy of KnownCipherSpecs, assuming that
+ * validCipherSpecs is currently not valid (i.e., SSLSetEnabledCiphers() has
+ * not been called).
+ */
+OSStatus sslBuildCipherSuiteArray(SSLContext *ctx)
+{
+ size_t size;
+ unsigned dex;
+
+ assert(ctx != NULL);
+ assert(ctx->validCipherSuites == NULL);
+
+ ctx->numValidCipherSuites = STCipherSuiteCount;
+ size = STCipherSuiteCount * sizeof(uint16_t);
+ ctx->validCipherSuites = (uint16_t *)sslMalloc(size);
+ if(ctx->validCipherSuites == NULL) {
+ ctx->numValidCipherSuites = 0;
+ return errSecAllocate;
+ }
+
+ /*
+ * Trim out inappropriate ciphers:
+ * -- trim anonymous ciphers if !ctx->anonCipherEnable
+ * -- trim ECDSA ciphers for server side if appropriate
+ * -- trim ECDSA ciphers if TLSv1 disable or SSLv2 enabled (since
+ * we MUST do the Client Hello extensions to make these ciphers
+ * work reliably)
+ * -- trim Stream ciphers if DTLSv1 enable
+ * -- trim CBC ciphers when doing SSLv3 fallback
+ */
+ uint16_t *dst = ctx->validCipherSuites;
+ const uint16_t *src = STKnownCipherSuites;
+
+ bool trimECDSA = false;
+ if((ctx->protocolSide==kSSLServerSide) && !SSL_ECDSA_SERVER) {
+ trimECDSA = true;
+ }
+ if(ctx->minProtocolVersion == SSL_Version_2_0
+ || ctx->maxProtocolVersion == SSL_Version_3_0) {
+ /* We trim ECDSA cipher suites if SSL2 is enabled or
+ The maximum allowed protocol is SSL3. Note that this
+ won't trim ECDSA cipherspecs for DTLS which should be
+ the right thing to do here. */
+ trimECDSA = true;
+ }
+
+ /* trim Stream Ciphers for DTLS */
+ bool trimRC4 = ctx->isDTLS;
+
+ /* trim CBC cipher when doing SSLv3 only fallback */
+ bool trimCBC = (ctx->protocolSide==kSSLClientSide)
+ && (ctx->maxProtocolVersion == SSL_Version_3_0)
+ && ctx->fallbackEnabled;
+
+ bool trimDHE = (ctx->protocolSide==kSSLServerSide) &&
+ !ctx->dhParamsEncoded.length;
+
+ for(dex=0; dex<STCipherSuiteCount; dex++) {
+ KeyExchangeMethod kem = sslCipherSuiteGetKeyExchangeMethod(*src);
+ uint8_t keySize = sslCipherSuiteGetSymmetricCipherKeySize(*src);
+ HMAC_Algs mac = sslCipherSuiteGetMacAlgorithm(*src);
+ SSL_CipherAlgorithm cipher = sslCipherSuiteGetSymmetricCipherAlgorithm(*src);
+ /* First skip ECDSA ciphers as appropriate */
+ switch(kem) {
+ case SSL_ECDH_ECDSA:
+ case SSL_ECDHE_ECDSA:
+ case SSL_ECDH_RSA:
+ case SSL_ECDHE_RSA:
+ case SSL_ECDH_anon:
+ if(trimECDSA) {
+ /* Skip this one */
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ }
+ else {
+ break;
+ }
+ default:
+ break;
+ }
+ if(!ctx->anonCipherEnable) {
+ /* trim out the anonymous (and null-auth-cipher) ciphers */
+ if(mac == HA_Null) {
+ /* skip this one */
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ }
+ switch(kem) {
+ case SSL_DH_anon:
+ case SSL_DH_anon_EXPORT:
+ case SSL_ECDH_anon:
+ /* skip this one */
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ default:
+ break;
+ }
+ }
+ if(ctx->falseStartEnabled) {
+ switch(kem){
+ case SSL_ECDHE_ECDSA:
+ case SSL_ECDHE_RSA:
+ case SSL_DHE_RSA:
+ case SSL_DHE_DSS:
+ /* Ok for false start */
+ break;
+ default:
+ /* Not ok, skip */
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ }
+ switch(cipher) {
+ case SSL_CipherAlgorithmAES_128_CBC:
+ case SSL_CipherAlgorithmAES_128_GCM:
+ case SSL_CipherAlgorithmAES_256_CBC:
+ case SSL_CipherAlgorithmAES_256_GCM:
+ case SSL_CipherAlgorithmRC4_128:
+ /* Ok for false start */
+ break;
+ default:
+ /* Not ok, skip*/
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ }
+ }
+
+ /* This will skip the simple DES cipher suites, but not the NULL cipher ones */
+ if (keySize == 8)
+ {
+ /* skip this one */
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ }
+
+ /* Trim PSK ciphersuites, they need to be enabled explicitely */
+ if (kem==TLS_PSK) {
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ }
+
+ if (trimDHE) {
+ switch(kem) {
+ case SSL_DHE_DSS:
+ case SSL_DHE_DSS_EXPORT:
+ case SSL_DHE_RSA:
+ case SSL_DHE_RSA_EXPORT:
+ /* skip this one */
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ default:
+ break;
+ }
+ }
+
+ if (trimRC4 && (cipher==SSL_CipherAlgorithmRC4_128)) {
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ }
+
+ if(trimCBC) {
+ switch (cipher) {
+ case SSL_CipherAlgorithmAES_128_CBC:
+ case SSL_CipherAlgorithmAES_256_CBC:
+ case SSL_CipherAlgorithm3DES_CBC:
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ default:
+ break;
+ }
+ }
+
+ if(cipher==SSL_CipherAlgorithmNull) {
+ ctx->numValidCipherSuites--;
+ src++;
+ continue;
+ }
+
+ /* This one is good to go */
+ *dst++ = *src++;
+ }
+
+ // sslAnalyzeCipherSpecs(ctx);
+
+ tls_handshake_set_ciphersuites(ctx->hdsk, ctx->validCipherSuites, ctx->numValidCipherSuites);
+
+ return errSecSuccess;
+}
+
+
+/*
+ * Convert an array of SSLCipherSuites (which is always KnownCipherSpecs)
+ * to an array of SSLCipherSuites.
+ */
+static OSStatus
+cipherSuitesToCipherSuites(
+ size_t numCipherSuites,
+ const uint16_t *cipherSuites,
+ SSLCipherSuite *ciphers, /* RETURNED */
+ size_t *numCiphers) /* IN/OUT */
+{
+ size_t i;
+ if(*numCiphers < numCipherSuites) {
+ return errSSLBufferOverflow;
+ }
+
+ /* NOTE: this is required to go from uint16_t to SSLCipherSuite
+ which is either 32 or 16 bits, depending on the platform */
+ for(i=0;i<numCipherSuites; i++) {
+ ciphers[i]=cipherSuites[i];
+ }
+ *numCiphers = numCipherSuites;
+ return errSecSuccess;
+}
+
+/***
+ *** Publically exported functions declared in SecureTransport.h
+ ***/
+
+/*
+ * Determine number and values of all of the SSLCipherSuites we support.
+ * Caller allocates output buffer for SSLGetSupportedCiphers() and passes in
+ * its size in *numCiphers. If supplied buffer is too small, errSSLBufferOverflow
+ * will be returned.
+ */
+OSStatus
+SSLGetNumberSupportedCiphers (SSLContextRef ctx,
+ size_t *numCiphers)
+{
+ if((ctx == NULL) || (numCiphers == NULL)) {
+ return errSecParam;
+ }
+ *numCiphers = STCipherSuiteCount;
+ return errSecSuccess;
+}
+
+OSStatus
+SSLGetSupportedCiphers (SSLContextRef ctx,
+ SSLCipherSuite *ciphers, /* RETURNED */
+ size_t *numCiphers) /* IN/OUT */
+{
+ if((ctx == NULL) || (ciphers == NULL) || (numCiphers == NULL)) {
+ return errSecParam;
+ }
+ return cipherSuitesToCipherSuites(STCipherSuiteCount,
+ STKnownCipherSuites,
+ ciphers,
+ numCiphers);
+}
+
+/*
+ * Specify a (typically) restricted set of SSLCipherSuites to be enabled by
+ * the current SSLContext. Can only be called when no session is active. Default
+ * set of enabled SSLCipherSuites is NOT the same as the complete set of supported
+ * SSLCipherSuites as obtained by SSLGetSupportedCiphers().
+ */
+OSStatus
+SSLSetEnabledCiphers (SSLContextRef ctx,
+ const SSLCipherSuite *ciphers,
+ size_t numCiphers)
+{
+ size_t size;
+ unsigned foundCiphers=0;
+ unsigned callerDex;
+ unsigned tableDex;
+
+ if((ctx == NULL) || (ciphers == NULL) || (numCiphers == 0)) {
+ return errSecParam;
+ }
+ if(sslIsSessionActive(ctx)) {
+ /* can't do this with an active session */
+ return errSecBadReq;
+ }
+ size = numCiphers * sizeof(uint16_t);
+ ctx->validCipherSuites = (uint16_t *)sslMalloc(size);
+ if(ctx->validCipherSuites == NULL) {
+ ctx->numValidCipherSuites = 0;
+ return errSecAllocate;
+ }
+
+ /*
+ * Run thru caller's specs, keep only the supported ones.
+ */
+ for(callerDex=0; callerDex<numCiphers; callerDex++) {
+ /* find matching CipherSpec in our known table */
+ for(tableDex=0; tableDex<STCipherSuiteCount; tableDex++) {
+ if(ciphers[callerDex] == STKnownCipherSuites[tableDex]) {
+ ctx->validCipherSuites[foundCiphers] = STKnownCipherSuites[tableDex];
+ foundCiphers++;
+ break;
+ }
+ }
+ }
+
+ if(foundCiphers==0) {
+ /* caller specified only unsupported ciphersuites */
+ sslFree(ctx->validCipherSuites);
+ ctx->validCipherSuites = NULL;
+ return errSSLBadCipherSuite;
+ }
+
+ /* success */
+ ctx->numValidCipherSuites = foundCiphers;
+
+ tls_handshake_set_ciphersuites(ctx->hdsk, ctx->validCipherSuites, ctx->numValidCipherSuites);
+
+ return errSecSuccess;
+}
+
+/*
+ * Determine number and values of all of the SSLCipherSuites currently enabled.
+ * Caller allocates output buffer for SSLGetEnabledCiphers() and passes in
+ * its size in *numCiphers. If supplied buffer is too small, errSSLBufferOverflow
+ * will be returned.
+ */
+OSStatus
+SSLGetNumberEnabledCiphers (SSLContextRef ctx,
+ size_t *numCiphers)
+{
+ if((ctx == NULL) || (numCiphers == NULL)) {
+ return errSecParam;
+ }
+ if(ctx->validCipherSuites == NULL) {
+ /* hasn't been set; use default */
+ *numCiphers = STCipherSuiteCount;
+ }
+ else {
+ /* caller set via SSLSetEnabledCiphers */
+ *numCiphers = ctx->numValidCipherSuites;
+ }
+ return errSecSuccess;
+}
+
+OSStatus
+SSLGetEnabledCiphers (SSLContextRef ctx,
+ SSLCipherSuite *ciphers, /* RETURNED */
+ size_t *numCiphers) /* IN/OUT */
+{
+ if((ctx == NULL) || (ciphers == NULL) || (numCiphers == NULL)) {
+ return errSecParam;
+ }
+ if(ctx->validCipherSuites == NULL) {
+ /* hasn't been set; use default */
+ return cipherSuitesToCipherSuites(STCipherSuiteCount,
+ STKnownCipherSuites,
+ ciphers,
+ numCiphers);
+ }
+ else {
+ /* use the ones specified in SSLSetEnabledCiphers() */
+ return cipherSuitesToCipherSuites(ctx->numValidCipherSuites,
+ ctx->validCipherSuites,
+ ciphers,
+ numCiphers);
+ }
+}
projects / apple / security.git / blobdiff