Security-54.tar.gz

[apple/security.git] / AppleCSP / DiffieHellman / DH_utils.cpp

diff --git a/AppleCSP/DiffieHellman/DH_utils.cpp b/AppleCSP/DiffieHellman/DH_utils.cpp
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+++ b/AppleCSP/DiffieHellman/DH_utils.cpp
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+/*
+ * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
+ * 
+ * The contents of this file constitute Original Code as defined in and are
+ * subject to the Apple Public Source License Version 1.2 (the 'License').
+ * You may not use this file except in compliance with the License. Please obtain
+ * a copy of the License at http://www.apple.com/publicsource and read it before
+ * using this file.
+ * 
+ * This 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.
+ */
+
+
+/*
+ * DH_utils.cpp
+ */
+
+#include "DH_utils.h"
+#include "DH_keys.h"
+#include <opensslUtils/openRsaSnacc.h>
+#include <Security/logging.h>
+#include <Security/debugging.h>
+#include <open_ssl/opensslUtils/opensslUtils.h>
+#include <openssl/bn.h>
+#include <openssl/dh.h>
+#include <openssl/err.h>
+
+#define dhMiscDebug(args...)   debug("dhMisc", ## args)
+
+/* 
+ * Given a Context:
+ * -- obtain CSSM key (there must only be one)
+ * -- validate keyClass - MUST be private! (DH public keys are never found
+ *    in contexts.)
+ * -- validate keyUsage
+ * -- convert to DH *, allocating the DH key if necessary
+ */
+DH *contextToDhKey(
+       const Context           &context,
+       AppleCSPSession         &session,
+       CSSM_KEYUSE                     usage,            // CSSM_KEYUSE_ENCRYPT, CSSM_KEYUSE_SIGN, etc.
+       bool                            &mallocdKey)  // RETURNED
+{
+    CssmKey &cssmKey = 
+               context.get<CssmKey>(CSSM_ATTRIBUTE_KEY, CSSMERR_CSP_MISSING_ATTR_KEY);
+       const CSSM_KEYHEADER &hdr = cssmKey.KeyHeader;
+       if(hdr.AlgorithmId != CSSM_ALGID_DH) {
+               CssmError::throwMe(CSSMERR_CSP_ALGID_MISMATCH);
+       }
+       if(hdr.KeyClass != CSSM_KEYCLASS_PRIVATE_KEY) {
+               CssmError::throwMe(CSSMERR_CSP_INVALID_KEY_CLASS);
+       }
+       cspValidateIntendedKeyUsage(&hdr, usage);
+       return cssmKeyToDh(cssmKey, session, mallocdKey);
+}
+/* 
+ * Convert a CssmKey (Private only!) to an DH * key. May result in the 
+ * creation of a new DH (when cssmKey is a raw key); allocdKey is true 
+ * in that case in which case the caller generally has to free the allocd key).
+ */
+DH *cssmKeyToDh(
+       const CssmKey   &cssmKey,
+       AppleCSPSession &session,
+       bool                    &allocdKey)             // RETURNED
+{
+       DH *dhKey = NULL;
+       allocdKey = false;
+       
+       const CSSM_KEYHEADER *hdr = &cssmKey.KeyHeader;
+       if(hdr->AlgorithmId != CSSM_ALGID_DH) {
+               // someone else's key (should never happen)
+               CssmError::throwMe(CSSMERR_CSP_INVALID_ALGORITHM);
+       }
+       assert(hdr->KeyClass == CSSM_KEYCLASS_PRIVATE_KEY);
+       switch(hdr->BlobType) {
+               case CSSM_KEYBLOB_RAW:
+                       dhKey = rawCssmKeyToDh(cssmKey);
+                       allocdKey = true;
+                       break;
+               case CSSM_KEYBLOB_REFERENCE:
+               {
+                       BinaryKey &binKey = session.lookupRefKey(cssmKey);
+                       DHBinaryKey *dhBinKey = dynamic_cast<DHBinaryKey *>(&binKey);
+                       /* this cast failing means that this is some other
+                        * kind of binary key */
+                       if(dhBinKey == NULL) {
+                               dhMiscDebug("cssmKeyToDh: wrong BinaryKey subclass\n");
+                               CssmError::throwMe(CSSMERR_CSP_INVALID_KEY);
+                       }
+                       assert(dhBinKey->mDhKey != NULL);
+                       dhKey = dhBinKey->mDhKey;
+                       break;
+               }
+               default:
+                       CssmError::throwMe(CSSMERR_CSP_KEY_BLOB_TYPE_INCORRECT);
+       }
+       return dhKey;
+}
+
+/* 
+ * Convert a raw CssmKey (Private only!)  to a newly alloc'd DH key.
+ */
+DH *rawCssmKeyToDh(
+       const CssmKey   &cssmKey)
+{
+       const CSSM_KEYHEADER *hdr = &cssmKey.KeyHeader;
+       
+       if(hdr->AlgorithmId != CSSM_ALGID_DH) {
+               // someone else's key (should never happen)
+               CssmError::throwMe(CSSMERR_CSP_INVALID_ALGORITHM);
+       }
+       assert(hdr->BlobType == CSSM_KEYBLOB_RAW); 
+       assert(hdr->KeyClass == CSSM_KEYCLASS_PRIVATE_KEY);
+       if(hdr->Format != DH_PRIV_KEY_FORMAT) {
+               CssmError::throwMe(CSSMERR_CSP_INVALID_ATTR_PRIVATE_KEY_FORMAT);
+       }
+       
+       DH *dhKey = DH_new();
+       if(dhKey == NULL) {
+               CssmError::throwMe(CSSMERR_CSP_MEMORY_ERROR);
+       }
+       CSSM_RETURN crtn;
+       crtn = DHPrivateKeyDecode(dhKey, 
+               cssmKey.KeyData.Data, 
+               cssmKey.KeyData.Length);
+       if(crtn) {
+               CssmError::throwMe(crtn);
+       }
+       return dhKey;
+}
+