+++ /dev/null
-//
-// OTRMath.c
-// libsecurity_libSecOTR
-//
-// Created by Mitch Adler on 1/28/11.
-// Copyright 2011 Apple Inc. All rights reserved.
-//
-
-#include "SecOTRMath.h"
-#include "SecOTRMathPrivate.h"
-
-#include "SecOTRPacketData.h"
-
-#include <AssertMacros.h>
-
-#include <pthread.h>
-
-#include <Security/SecRandom.h>
-
-#include <corecrypto/ccsha2.h>
-#include <corecrypto/cczp.h>
-
-#include <limits.h>
-
-static inline
-void cczp_init_from_bytes(cc_size n, cczp_t zp, size_t pSize, const void *p, size_t rSize, const void* r)
-{
- CCZP_N(zp) = n;
- zp.zp->mod_prime = cczp_mod;
- ccn_read_uint(n, CCZP_PRIME(zp), pSize, p);
- ccn_read_uint(n+1, CCZP_RECIP(zp), rSize, r);
-
-}
-
-static pthread_once_t kOTRImportGroupData = PTHREAD_ONCE_INIT;
-
-static cc_unit sOTRGenerator[kOTRDHGroupUnits];
-static cczp_decl_n(kOTRDHGroupUnits, sOTRGroup_zp);
-
-static void setupGroupValues()
-{
- __Check( kExponentiationUnits == kOTRDHGroupUnits );
-
- cczp_init_from_bytes(kOTRDHGroupUnits, sOTRGroup_zp,
- sizeof(kOTRDHGroup), kOTRDHGroup,
- sizeof(kOTRDHGroup_Recip), kOTRDHGroup_Recip);
-
- ccn_seti(kOTRDHGroupUnits, sOTRGenerator, kOTRGeneratorValue);
-}
-
-void OTRExponentiate(cc_unit* res, const cc_unit* base, const cc_unit* exponent)
-{
- pthread_once(&kOTRImportGroupData, setupGroupValues);
-
- cczp_power(sOTRGroup_zp, res, base, exponent);
-}
-
-void OTRGroupExponentiate(cc_unit* res, const cc_unit* exponent)
-{
- pthread_once(&kOTRImportGroupData, setupGroupValues);
-
- OTRExponentiate(res, sOTRGenerator, exponent);
-}
-
-//
-// Random Number Generation
-//
-
-OSStatus GetRandomBytesInLSBs(size_t bytesOfRandomness, size_t n, cc_unit* place)
-{
- OSStatus result = errSecParam;
- require(bytesOfRandomness * 8 <= ccn_bitsof_n(n), fail);
- {
- uint8_t randomBytes[bytesOfRandomness];
-
- result = SecRandomCopyBytes(kSecRandomDefault, sizeof(randomBytes), randomBytes);
-
- require_noerr(result, fail);
-
- ccn_read_uint(n, place, sizeof(randomBytes), randomBytes);
-
- bzero(randomBytes, bytesOfRandomness);
- }
-fail:
- return result;
-}
-
-OSStatus FillWithRandomBytes(size_t n, cc_unit* place)
-{
- return GetRandomBytesInLSBs(ccn_sizeof(n), n, place);
-}
-
-
-static const uint8_t kIVZero[16] = { };
-
-static void AES_CTR_Transform(size_t keySize, const uint8_t* key,
- const uint8_t iv[16],
- size_t howMuch, const uint8_t* from, uint8_t* to)
-{
- const struct ccmode_ctr* ctr_encrypt = ccaes_ctr_crypt_mode();
- ccctr_ctx_decl(ctr_encrypt->size, ctr_ctx);
- ctr_encrypt->init(ctr_encrypt, ctr_ctx, keySize, key, iv);
-
- ctr_encrypt->ctr(ctr_ctx, howMuch, from, to);
-}
-
-void AES_CTR_HighHalf_Transform(size_t keySize, const uint8_t* key,
- uint64_t highHalf,
- size_t howMuch, const uint8_t* from, uint8_t* to)
-{
- uint8_t iv[16] = { highHalf >> 56, highHalf >> 48, highHalf >> 40, highHalf >> 32,
- highHalf >> 24, highHalf >> 16, highHalf >> 8 , highHalf >> 0,
- 0, 0, 0, 0,
- 0, 0, 0, 0 };
- AES_CTR_Transform(keySize, key, iv, howMuch, from, to);
-}
-
-void AES_CTR_IV0_Transform(size_t keySize, const uint8_t* key,
- size_t howMuch, const uint8_t* from, uint8_t* to)
-{
- AES_CTR_Transform(keySize, key, kIVZero, howMuch, from, to);
-}
-
-
-//
-// Key Derivation
-//
-
-static void HashMPIWithPrefix(uint8_t byte, cc_size sN, const cc_unit* s, uint8_t* buffer)
-{
- CFMutableDataRef dataToHash = CFDataCreateMutable(kCFAllocatorDefault, 0);
- CFDataAppendBytes(dataToHash, &byte, 1);
-
- AppendMPI(dataToHash, sN, s);
-
- uint8_t *bytesToHash = CFDataGetMutableBytePtr(dataToHash);
- CFIndex amountToHash = CFDataGetLength(dataToHash);
-
- /* 64 bits cast: amountToHash is the size of an identity +1 , which is currently hardcoded and never more than 2^32 bytes */
- assert((unsigned long)amountToHash<UINT32_MAX); /* Debug check, Correct as long as CFIndex is a signed long and CC_LONG is a uint32_t */
-
- (void) CC_SHA256(bytesToHash, (CC_LONG)amountToHash, buffer);
-
- bzero(bytesToHash, (size_t)amountToHash);
- CFReleaseNull(dataToHash);
-}
-
-void DeriveOTR256BitsFromS(KeyType whichKey, cc_size sN, const cc_unit* s, size_t keySize, uint8_t* key)
-{
- HashMPIWithPrefix(whichKey, sN, s, key);
-}
-
-void DeriveOTR128BitPairFromS(KeyType whichKey, size_t sSize, const cc_unit* s,
- size_t firstKeySize, uint8_t* firstKey,
- size_t secondKeySize, uint8_t* secondKey)
-{
- uint8_t hashBuffer[CCSHA256_OUTPUT_SIZE];
-
- HashMPIWithPrefix(whichKey, sSize, s, hashBuffer);
-
- if (firstKey) {
- firstKeySize = firstKeySize > CCSHA256_OUTPUT_SIZE/2 ? CCSHA256_OUTPUT_SIZE/2 : firstKeySize;
- memcpy(firstKey, hashBuffer, firstKeySize);
- }
- if (secondKey) {
- secondKeySize = secondKeySize > CCSHA256_OUTPUT_SIZE/2 ? CCSHA256_OUTPUT_SIZE/2 : secondKeySize;
- memcpy(secondKey, hashBuffer, secondKeySize);
- }
-
- bzero(hashBuffer, CCSHA256_OUTPUT_SIZE);
-
-}
-
-void DeriveOTR64BitsFromS(KeyType whichKey, size_t sn, const cc_unit* s,
- size_t topKeySize, uint8_t* topKey)
-{
- uint8_t hashBuffer[CCSHA256_OUTPUT_SIZE];
-
- HashMPIWithPrefix(whichKey, sn, s, hashBuffer);
-
- topKeySize = topKeySize > CCSHA256_OUTPUT_SIZE/2 ? CCSHA256_OUTPUT_SIZE/2 : topKeySize;
- memcpy(topKey, hashBuffer, topKeySize);
-
- bzero(hashBuffer, CCSHA256_OUTPUT_SIZE);
-}
-
projects / apple / security.git / blobdiff