OSX/libsecurity_apple_csp/lib/SignatureContext.cpp

   1 /*
   2  * Copyright (c) 2000-2001,2011,2014 Apple Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18
  19 /*
  20  * SignatureContext.h - AppleCSPContext sublass for generic sign/verify
  21  */
  22
  23 #include "SignatureContext.h"
  24 #include "AppleCSPUtils.h"
  25 #include "AppleCSPSession.h"
  26 #include <Security/cssmtype.h>
  27
  28 #include <security_utilities/debugging.h>
  29
  30 #define cspSigDebug(args...)    secdebug("cspSig", ## args)
  31
  32 SignatureContext::~SignatureContext()
  33 {
  34         delete &mDigest;
  35         delete &mSigner;
  36         mInitFlag = false;
  37 }
  38
  39 /* both sign & verify */
  40 void SignatureContext::init(
  41         const Context &context,
  42         bool isSigning)
  43 {
  44         mDigest.digestInit();
  45         mSigner.signerInit(context, isSigning);
  46         mInitFlag = true;
  47 }
  48
  49 /* both sign & verify */
  50 void SignatureContext::update(
  51         const CssmData &data)
  52 {
  53         mDigest.digestUpdate(data.Data, data.Length);
  54 }
  55
  56 /* sign only */
  57 void SignatureContext::final(
  58         CssmData &out)
  59 {
  60         void            *digest;
  61         size_t          digestLen;
  62         void            *sig = out.data();
  63         size_t          sigLen = out.length();
  64
  65         /* first obtain the digest */
  66         digestLen = mDigest.digestSizeInBytes();
  67         digest = session().malloc(digestLen);
  68         mDigest.digestFinal(digest);
  69
  70         /* now sign */
  71         try {
  72                 mSigner.sign(digest,
  73                         digestLen,
  74                         sig,
  75                         &sigLen);
  76         }
  77         catch(...) {
  78                 session().free(digest);
  79                 throw;
  80         }
  81         session().free(digest);
  82         if(out.length() < sigLen) {
  83                 cspSigDebug("SignatureContext: mallocd sig too small!");
  84                 CssmError::throwMe(CSSMERR_CSP_INTERNAL_ERROR);
  85         }
  86         out.length(sigLen);
  87 }
  88
  89 /* verify only */
  90 void SignatureContext::final(
  91         const CssmData &in)
  92 {
  93         void            *digest;
  94         size_t          digestLen;
  95
  96         /* first obtain the digest */
  97         digestLen = mDigest.digestSizeInBytes();
  98         digest = session().malloc(digestLen);
  99         mDigest.digestFinal(digest);
 100
 101         /* now verify */
 102         try {
 103                 mSigner.verify(digest,
 104                         digestLen,
 105                         in.Data,
 106                         in.Length);
 107         }
 108         catch(...) {
 109                 session().free(digest);
 110                 throw;
 111         }
 112         session().free(digest);
 113 }
 114
 115 size_t SignatureContext::outputSize(
 116         bool final,
 117         size_t inSize)
 118 {
 119         return mSigner.maxSigSize();
 120 }
 121
 122 /* for raw sign/verify - optionally called after init */
 123 void SignatureContext::setDigestAlgorithm(
 124         CSSM_ALGORITHMS digestAlg)
 125 {
 126         mSigner.setDigestAlg(digestAlg);
 127 }