X-Git-Url: https://git.saurik.com/apple/security.git/blobdiff_plain/c25717e3bfe9397829b8aac32a966f746fc3c4f5..2965425374ca4413339436c2f706f7b5508402e2:/AppleCSP/DiffieHellman/DH_utils.cpp diff --git a/AppleCSP/DiffieHellman/DH_utils.cpp b/AppleCSP/DiffieHellman/DH_utils.cpp new file mode 100644 index 00000000..c1ecce3f --- /dev/null +++ b/AppleCSP/DiffieHellman/DH_utils.cpp @@ -0,0 +1,136 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include + +#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(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(&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; +} +