libsecurity_ssl/lib/sslHandshakeFinish.c

   1 /*
   2  * Copyright (c) 1999-2001,2005-2007,2010-2012 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*
  25  * sslHandshakeFinish.c - Finished and server hello done messages.
  26  */
  27
  28 #include "sslContext.h"
  29 #include "sslHandshake.h"
  30 #include "sslMemory.h"
  31 #include "sslDebug.h"
  32 #include "sslUtils.h"
  33 #include "sslDigests.h"
  34
  35 #include <string.h>
  36 #include <assert.h>
  37
  38 OSStatus
  39 SSLEncodeFinishedMessage(SSLRecord *finished, SSLContext *ctx)
  40 {   OSStatus        err;
  41     SSLBuffer       finishedMsg;
  42     Boolean         isServerMsg;
  43     unsigned            finishedSize;
  44         UInt8           *p;
  45     int             head;
  46
  47         /* size and version depend on negotiatedProtocol */
  48         switch(ctx->negProtocolVersion) {
  49                 case SSL_Version_3_0:
  50                         finishedSize = 36;
  51                         break;
  52         case DTLS_Version_1_0:
  53                 case TLS_Version_1_0:
  54         case TLS_Version_1_1:
  55         case TLS_Version_1_2: /* TODO: Support variable finishedSize. */
  56                         finishedSize = 12;
  57                         break;
  58                 default:
  59                         assert(0);
  60                         return errSSLInternal;
  61         }
  62     finished->protocolVersion = ctx->negProtocolVersion;
  63
  64     finished->contentType = SSL_RecordTypeHandshake;
  65         /* msg = type + 3 bytes len + finishedSize */
  66     head = SSLHandshakeHeaderSize(finished);
  67     if ((err = SSLAllocBuffer(&finished->contents, finishedSize + head)) != 0)
  68         return err;
  69
  70     p = SSLEncodeHandshakeHeader(ctx, finished, SSL_HdskFinished, finishedSize);
  71
  72     finishedMsg.data = p;
  73     finishedMsg.length = finishedSize;
  74
  75     isServerMsg = (ctx->protocolSide == kSSLServerSide) ? true : false;
  76     err = ctx->sslTslCalls->computeFinishedMac(ctx, finishedMsg, isServerMsg);
  77
  78     if(err)
  79         return err;
  80
  81     /* Keep this around for secure renegotiation */
  82     SSLFreeBuffer(&ctx->ownVerifyData);
  83     return SSLCopyBuffer(&finishedMsg, &ctx->ownVerifyData);
  84 }
  85
  86 OSStatus
  87 SSLProcessFinished(SSLBuffer message, SSLContext *ctx)
  88 {   OSStatus        err;
  89     SSLBuffer       expectedFinished;
  90     Boolean         isServerMsg;
  91     unsigned            finishedSize;
  92
  93         switch(ctx->negProtocolVersion) {
  94                 case SSL_Version_3_0:
  95                         finishedSize = 36;
  96                         break;
  97                 case DTLS_Version_1_0:
  98                 case TLS_Version_1_0:
  99         case TLS_Version_1_1:
 100         case TLS_Version_1_2: /* TODO: Support variable finishedSize. */
 101                         finishedSize = 12;
 102                         break;
 103                 default:
 104                         assert(0);
 105                         return errSSLInternal;
 106         }
 107     if (message.length != finishedSize) {
 108                 sslErrorLog("SSLProcessFinished: msg len error 1\n");
 109         return errSSLProtocol;
 110     }
 111     expectedFinished.data = 0;
 112     if ((err = SSLAllocBuffer(&expectedFinished, finishedSize)))
 113         return err;
 114     isServerMsg = (ctx->protocolSide == kSSLServerSide) ? false : true;
 115     if ((err = ctx->sslTslCalls->computeFinishedMac(ctx, expectedFinished, isServerMsg)) != 0)
 116         goto fail;
 117
 118     if (memcmp(expectedFinished.data, message.data, finishedSize) != 0)
 119     {
 120                 sslErrorLog("SSLProcessFinished: memcmp failure\n");
 121                 err = errSSLProtocol;
 122         goto fail;
 123     }
 124
 125     /* Keep this around for secure renegotiation */
 126     SSLFreeBuffer(&ctx->peerVerifyData);
 127     err = SSLCopyBuffer(&expectedFinished, &ctx->peerVerifyData);
 128
 129 fail:
 130     SSLFreeBuffer(&expectedFinished);
 131     return err;
 132 }
 133
 134 OSStatus
 135 SSLEncodeServerHelloDone(SSLRecord *helloDone, SSLContext *ctx)
 136 {   OSStatus          err;
 137     int               head;
 138
 139     helloDone->contentType = SSL_RecordTypeHandshake;
 140         assert(ctx->negProtocolVersion >= SSL_Version_3_0);
 141     helloDone->protocolVersion = ctx->negProtocolVersion;
 142     head = SSLHandshakeHeaderSize(helloDone);
 143     if ((err = SSLAllocBuffer(&helloDone->contents, head)))
 144         return err;
 145
 146     SSLEncodeHandshakeHeader(ctx, helloDone, SSL_HdskServerHelloDone, 0); /* Message has 0 length */
 147
 148     return errSecSuccess;
 149 }
 150
 151 OSStatus
 152 SSLProcessServerHelloDone(SSLBuffer message, SSLContext *ctx)
 153 {   assert(ctx->protocolSide == kSSLClientSide);
 154     if (message.length != 0) {
 155         sslErrorLog("SSLProcessServerHelloDone: nonzero msg len\n");
 156         return errSSLProtocol;
 157     }
 158     return errSecSuccess;
 159 }