Index: mozilla/security/nss/lib/freebl/gcm.c |
=================================================================== |
--- mozilla/security/nss/lib/freebl/gcm.c (revision 191424) |
+++ mozilla/security/nss/lib/freebl/gcm.c (working copy) |
@@ -1,846 +0,0 @@ |
-/* This Source Code Form is subject to the terms of the Mozilla Public |
- * License, v. 2.0. If a copy of the MPL was not distributed with this |
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
- |
-#ifdef FREEBL_NO_DEPEND |
-#include "stubs.h" |
-#endif |
-#include "blapii.h" |
-#include "blapit.h" |
-#include "gcm.h" |
-#include "ctr.h" |
-#include "secerr.h" |
-#include "prtypes.h" |
-#include "pkcs11t.h" |
- |
-#include <limits.h> |
- |
-/************************************************************************** |
- * First implement the Galois hash function of GCM (gcmHash) * |
- **************************************************************************/ |
-#define GCM_HASH_LEN_LEN 8 /* gcm hash defines lengths to be 64 bits */ |
- |
-typedef struct gcmHashContextStr gcmHashContext; |
- |
-static SECStatus gcmHash_InitContext(gcmHashContext *hash, |
- const unsigned char *H, |
- unsigned int blocksize); |
-static void gcmHash_DestroyContext(gcmHashContext *ghash, PRBool freeit); |
-static SECStatus gcmHash_Update(gcmHashContext *ghash, |
- const unsigned char *buf, unsigned int len, |
- unsigned int blocksize); |
-static SECStatus gcmHash_Sync(gcmHashContext *ghash, unsigned int blocksize); |
-static SECStatus gcmHash_Final(gcmHashContext *gcm, unsigned char *outbuf, |
- unsigned int *outlen, unsigned int maxout, |
- unsigned int blocksize); |
-static SECStatus gcmHash_Reset(gcmHashContext *ghash, |
- const unsigned char *inbuf, |
- unsigned int inbufLen, unsigned int blocksize); |
- |
-/* compile time defines to select how the GF2 multiply is calculated. |
- * There are currently 2 algorithms implemented here: MPI and ALGORITHM_1. |
- * |
- * MPI uses the GF2m implemented in mpi to support GF2 ECC. |
- * ALGORITHM_1 is the Algorithm 1 in both NIST SP 800-38D and |
- * "The Galois/Counter Mode of Operation (GCM)", McGrew & Viega. |
- */ |
-#if !defined(GCM_USE_ALGORITHM_1) && !defined(GCM_USE_MPI) |
-#define GCM_USE_MPI 1 /* MPI is about 5x faster with the |
- * same or less complexity. It's possible to use |
- * tables to speed things up even more */ |
-#endif |
- |
-/* GCM defines the bit string to be LSB first, which is exactly |
- * opposite everyone else, including hardware. build array |
- * to reverse everything. */ |
-static const unsigned char gcm_byte_rev[256] = { |
- 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, |
- 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0, |
- 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, |
- 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, |
- 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, |
- 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4, |
- 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, |
- 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc, |
- 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, |
- 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2, |
- 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, |
- 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa, |
- 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, |
- 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6, |
- 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, |
- 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, |
- 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, |
- 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1, |
- 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, |
- 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9, |
- 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, |
- 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5, |
- 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, |
- 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd, |
- 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, |
- 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3, |
- 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, |
- 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb, |
- 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, |
- 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7, |
- 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, |
- 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff |
-}; |
- |
- |
-#ifdef GCM_TRACE |
-#include <stdio.h> |
- |
-#define GCM_TRACE_X(ghash,label) { \ |
- unsigned char _X[MAX_BLOCK_SIZE]; int i; \ |
- gcm_getX(ghash, _X, blocksize); \ |
- printf(label,(ghash)->m); \ |
- for (i=0; i < blocksize; i++) printf("%02x",_X[i]); \ |
- printf("\n"); } |
-#define GCM_TRACE_BLOCK(label,buf,blocksize) {\ |
- printf(label); \ |
- for (i=0; i < blocksize; i++) printf("%02x",buf[i]); \ |
- printf("\n"); } |
-#else |
-#define GCM_TRACE_X(ghash,label) |
-#define GCM_TRACE_BLOCK(label,buf,blocksize) |
-#endif |
- |
-#ifdef GCM_USE_MPI |
- |
-#ifdef GCM_USE_ALGORITHM_1 |
-#error "Only define one of GCM_USE_MPI, GCM_USE_ALGORITHM_1" |
-#endif |
-/* use the MPI functions to calculate Xn = (Xn-1^C_i)*H mod poly */ |
-#include "mpi.h" |
-#include "secmpi.h" |
-#include "mplogic.h" |
-#include "mp_gf2m.h" |
- |
-/* state needed to handle GCM Hash function */ |
-struct gcmHashContextStr { |
- mp_int H; |
- mp_int X; |
- mp_int C_i; |
- const unsigned int *poly; |
- unsigned char buffer[MAX_BLOCK_SIZE]; |
- unsigned int bufLen; |
- int m; /* XXX what is m? */ |
- unsigned char counterBuf[2*GCM_HASH_LEN_LEN]; |
- PRUint64 cLen; |
-}; |
- |
-/* f = x^128 + x^7 + x^2 + x + 1 */ |
-static const unsigned int poly_128[] = { 128, 7, 2, 1, 0 }; |
- |
-/* sigh, GCM defines the bit strings exactly backwards from everything else */ |
-static void |
-gcm_reverse(unsigned char *target, const unsigned char *src, |
- unsigned int blocksize) |
-{ |
- unsigned int i; |
- for (i=0; i < blocksize; i++) { |
- target[blocksize-i-1] = gcm_byte_rev[src[i]]; |
- } |
-} |
- |
-/* Initialize a gcmHashContext */ |
-static SECStatus |
-gcmHash_InitContext(gcmHashContext *ghash, const unsigned char *H, |
- unsigned int blocksize) |
-{ |
- mp_err err = MP_OKAY; |
- unsigned char H_rev[MAX_BLOCK_SIZE]; |
- |
- MP_DIGITS(&ghash->H) = 0; |
- MP_DIGITS(&ghash->X) = 0; |
- MP_DIGITS(&ghash->C_i) = 0; |
- CHECK_MPI_OK( mp_init(&ghash->H) ); |
- CHECK_MPI_OK( mp_init(&ghash->X) ); |
- CHECK_MPI_OK( mp_init(&ghash->C_i) ); |
- |
- mp_zero(&ghash->X); |
- gcm_reverse(H_rev, H, blocksize); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&ghash->H, H_rev, blocksize) ); |
- |
- /* set the irreducible polynomial. Each blocksize has its own polynomial. |
- * for now only blocksize 16 (=128 bits) is defined */ |
- switch (blocksize) { |
- case 16: /* 128 bits */ |
- ghash->poly = poly_128; |
- break; |
- default: |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- goto cleanup; |
- } |
- ghash->cLen = 0; |
- ghash->bufLen = 0; |
- ghash->m = 0; |
- PORT_Memset(ghash->counterBuf, 0, sizeof(ghash->counterBuf)); |
- return SECSuccess; |
-cleanup: |
- gcmHash_DestroyContext(ghash, PR_FALSE); |
- return SECFailure; |
-} |
- |
-/* Destroy a HashContext (Note we zero the digits so this function |
- * is idempotent if called with freeit == PR_FALSE */ |
-static void |
-gcmHash_DestroyContext(gcmHashContext *ghash, PRBool freeit) |
-{ |
- mp_clear(&ghash->H); |
- mp_clear(&ghash->X); |
- mp_clear(&ghash->C_i); |
- MP_DIGITS(&ghash->H) = 0; |
- MP_DIGITS(&ghash->X) = 0; |
- MP_DIGITS(&ghash->C_i) = 0; |
- if (freeit) { |
- PORT_Free(ghash); |
- } |
-} |
- |
-static SECStatus |
-gcm_getX(gcmHashContext *ghash, unsigned char *T, unsigned int blocksize) |
-{ |
- int len; |
- mp_err err; |
- unsigned char tmp_buf[MAX_BLOCK_SIZE]; |
- unsigned char *X; |
- |
- len = mp_unsigned_octet_size(&ghash->X); |
- if (len <= 0) { |
- PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); |
- return SECFailure; |
- } |
- X = tmp_buf; |
- PORT_Assert((unsigned int)len <= blocksize); |
- if ((unsigned int)len > blocksize) { |
- PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); |
- return SECFailure; |
- } |
- /* zero pad the result */ |
- if (len != blocksize) { |
- PORT_Memset(X,0,blocksize-len); |
- X += blocksize-len; |
- } |
- |
- err = mp_to_unsigned_octets(&ghash->X, X, len); |
- if (err < 0) { |
- PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); |
- return SECFailure; |
- } |
- gcm_reverse(T, tmp_buf, blocksize); |
- return SECSuccess; |
-} |
- |
-static SECStatus |
-gcm_HashMult(gcmHashContext *ghash, const unsigned char *buf, |
- unsigned int count, unsigned int blocksize) |
-{ |
- SECStatus rv = SECFailure; |
- mp_err err = MP_OKAY; |
- unsigned char tmp_buf[MAX_BLOCK_SIZE]; |
- unsigned int i; |
- |
- for (i=0; i < count; i++, buf += blocksize) { |
- ghash->m++; |
- gcm_reverse(tmp_buf, buf, blocksize); |
- CHECK_MPI_OK(mp_read_unsigned_octets(&ghash->C_i, tmp_buf, blocksize)); |
- CHECK_MPI_OK(mp_badd(&ghash->X, &ghash->C_i, &ghash->C_i)); |
- /* |
- * Looking to speed up GCM, this the the place to do it. |
- * There are two areas that can be exploited to speed up this code. |
- * |
- * 1) H is a constant in this multiply. We can precompute H * (0 - 255) |
- * at init time and this becomes an blockize xors of our table lookup. |
- * |
- * 2) poly is a constant for each blocksize. We can calculate the |
- * modulo reduction by a series of adds and shifts. |
- * |
- * For now we are after functionality, so we will go ahead and use |
- * the builtin bmulmod from mpi |
- */ |
- CHECK_MPI_OK(mp_bmulmod(&ghash->C_i, &ghash->H, |
- ghash->poly, &ghash->X)); |
- GCM_TRACE_X(ghash, "X%d = ") |
- } |
- rv = SECSuccess; |
-cleanup: |
- if (rv != SECSuccess) { |
- MP_TO_SEC_ERROR(err); |
- } |
- return rv; |
-} |
- |
-static void |
-gcm_zeroX(gcmHashContext *ghash) |
-{ |
- mp_zero(&ghash->X); |
- ghash->m = 0; |
-} |
- |
-#endif |
- |
-#ifdef GCM_USE_ALGORITHM_1 |
-/* use algorithm 1 of McGrew & Viega "The Galois/Counter Mode of Operation" */ |
- |
-#define GCM_ARRAY_SIZE (MAX_BLOCK_SIZE/sizeof(unsigned long)) |
- |
-struct gcmHashContextStr { |
- unsigned long H[GCM_ARRAY_SIZE]; |
- unsigned long X[GCM_ARRAY_SIZE]; |
- unsigned long R; |
- unsigned char buffer[MAX_BLOCK_SIZE]; |
- unsigned int bufLen; |
- int m; |
- unsigned char counterBuf[2*GCM_HASH_LEN_LEN]; |
- PRUint64 cLen; |
-}; |
- |
-static void |
-gcm_bytes_to_longs(unsigned long *l, const unsigned char *c, unsigned int len) |
-{ |
- int i,j; |
- int array_size = len/sizeof(unsigned long); |
- |
- PORT_Assert(len % sizeof(unsigned long) == 0); |
- for (i=0; i < array_size; i++) { |
- unsigned long tmp = 0; |
- int byte_offset = i * sizeof(unsigned long); |
- for (j=sizeof(unsigned long)-1; j >= 0; j--) { |
- tmp = (tmp << PR_BITS_PER_BYTE) | gcm_byte_rev[c[byte_offset+j]]; |
- } |
- l[i] = tmp; |
- } |
-} |
- |
-static void |
-gcm_longs_to_bytes(const unsigned long *l, unsigned char *c, unsigned int len) |
-{ |
- int i,j; |
- int array_size = len/sizeof(unsigned long); |
- |
- PORT_Assert(len % sizeof(unsigned long) == 0); |
- for (i=0; i < array_size; i++) { |
- unsigned long tmp = l[i]; |
- int byte_offset = i * sizeof(unsigned long); |
- for (j=0; j < sizeof(unsigned long); j++) { |
- c[byte_offset+j] = gcm_byte_rev[tmp & 0xff]; |
- tmp = (tmp >> PR_BITS_PER_BYTE); |
- } |
- } |
-} |
- |
- |
-/* Initialize a gcmHashContext */ |
-static SECStatus |
-gcmHash_InitContext(gcmHashContext *ghash, const unsigned char *H, |
- unsigned int blocksize) |
-{ |
- PORT_Memset(ghash->X, 0, sizeof(ghash->X)); |
- PORT_Memset(ghash->H, 0, sizeof(ghash->H)); |
- gcm_bytes_to_longs(ghash->H, H, blocksize); |
- |
- /* set the irreducible polynomial. Each blocksize has its own polynommial |
- * for now only blocksize 16 (=128 bits) is defined */ |
- switch (blocksize) { |
- case 16: /* 128 bits */ |
- ghash->R = (unsigned long) 0x87; /* x^7 + x^2 + x +1 */ |
- break; |
- default: |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- goto cleanup; |
- } |
- ghash->cLen = 0; |
- ghash->bufLen = 0; |
- ghash->m = 0; |
- PORT_Memset(ghash->counterBuf, 0, sizeof(ghash->counterBuf)); |
- return SECSuccess; |
-cleanup: |
- return SECFailure; |
-} |
- |
-/* Destroy a HashContext (Note we zero the digits so this function |
- * is idempotent if called with freeit == PR_FALSE */ |
-static void |
-gcmHash_DestroyContext(gcmHashContext *ghash, PRBool freeit) |
-{ |
- if (freeit) { |
- PORT_Free(ghash); |
- } |
-} |
- |
-static unsigned long |
-gcm_shift_one(unsigned long *t, unsigned int count) |
-{ |
- unsigned long carry = 0; |
- unsigned long nextcarry = 0; |
- unsigned int i; |
- for (i=0; i < count; i++) { |
- nextcarry = t[i] >> ((sizeof(unsigned long)*PR_BITS_PER_BYTE)-1); |
- t[i] = (t[i] << 1) | carry; |
- carry = nextcarry; |
- } |
- return carry; |
-} |
- |
-static SECStatus |
-gcm_getX(gcmHashContext *ghash, unsigned char *T, unsigned int blocksize) |
-{ |
- gcm_longs_to_bytes(ghash->X, T, blocksize); |
- return SECSuccess; |
-} |
- |
-#define GCM_XOR(t, s, len) \ |
- for (l=0; l < len; l++) t[l] ^= s[l] |
- |
-static SECStatus |
-gcm_HashMult(gcmHashContext *ghash, const unsigned char *buf, |
- unsigned int count, unsigned int blocksize) |
-{ |
- unsigned long C_i[GCM_ARRAY_SIZE]; |
- unsigned int arraysize = blocksize/sizeof(unsigned long); |
- unsigned int i, j, k, l; |
- |
- for (i=0; i < count; i++, buf += blocksize) { |
- ghash->m++; |
- gcm_bytes_to_longs(C_i, buf, blocksize); |
- GCM_XOR(C_i, ghash->X, arraysize); |
- /* multiply X = C_i * H */ |
- PORT_Memset(ghash->X, 0, sizeof(ghash->X)); |
- for (j=0; j < arraysize; j++) { |
- unsigned long H = ghash->H[j]; |
- for (k=0; k < sizeof(unsigned long)*PR_BITS_PER_BYTE; k++) { |
- if (H & 1) { |
- GCM_XOR(ghash->X, C_i, arraysize); |
- } |
- if (gcm_shift_one(C_i, arraysize)) { |
- C_i[0] = C_i[0] ^ ghash->R; |
- } |
- H = H >> 1; |
- } |
- } |
- GCM_TRACE_X(ghash, "X%d = ") |
- } |
- return SECSuccess; |
-} |
- |
- |
-static void |
-gcm_zeroX(gcmHashContext *ghash) |
-{ |
- PORT_Memset(ghash->X, 0, sizeof(ghash->X)); |
- ghash->m = 0; |
-} |
-#endif |
- |
-/* |
- * implement GCM GHASH using the freebl GHASH function. The gcm_HashMult |
- * function always takes blocksize lengths of data. gcmHash_Update will |
- * format the data properly. |
- */ |
-static SECStatus |
-gcmHash_Update(gcmHashContext *ghash, const unsigned char *buf, |
- unsigned int len, unsigned int blocksize) |
-{ |
- unsigned int blocks; |
- SECStatus rv; |
- |
- ghash->cLen += (len*PR_BITS_PER_BYTE); |
- |
- /* first deal with the current buffer of data. Try to fill it out so |
- * we can hash it */ |
- if (ghash->bufLen) { |
- unsigned int needed = PR_MIN(len, blocksize - ghash->bufLen); |
- if (needed != 0) { |
- PORT_Memcpy(ghash->buffer+ghash->bufLen, buf, needed); |
- } |
- buf += needed; |
- len -= needed; |
- ghash->bufLen += needed; |
- if (len == 0) { |
- /* didn't add enough to hash the data, nothing more do do */ |
- return SECSuccess; |
- } |
- PORT_Assert(ghash->bufLen == blocksize); |
- /* hash the buffer and clear it */ |
- rv = gcm_HashMult(ghash, ghash->buffer, 1, blocksize); |
- PORT_Memset(ghash->buffer, 0, blocksize); |
- ghash->bufLen = 0; |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- } |
- /* now hash any full blocks remaining in the data stream */ |
- blocks = len/blocksize; |
- if (blocks) { |
- rv = gcm_HashMult(ghash, buf, blocks, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- buf += blocks*blocksize; |
- len -= blocks*blocksize; |
- } |
- |
- /* save any remainder in the buffer to be hashed with the next call */ |
- if (len != 0) { |
- PORT_Memcpy(ghash->buffer, buf, len); |
- ghash->bufLen = len; |
- } |
- return SECSuccess; |
-} |
- |
-/* |
- * write out any partial blocks zero padded through the GHASH engine, |
- * save the lengths for the final completion of the hash |
- */ |
-static SECStatus |
-gcmHash_Sync(gcmHashContext *ghash, unsigned int blocksize) |
-{ |
- int i; |
- SECStatus rv; |
- |
- /* copy the previous counter to the upper block */ |
- PORT_Memcpy(ghash->counterBuf, &ghash->counterBuf[GCM_HASH_LEN_LEN], |
- GCM_HASH_LEN_LEN); |
- /* copy the current counter in the lower block */ |
- for (i=0; i < GCM_HASH_LEN_LEN; i++) { |
- ghash->counterBuf[GCM_HASH_LEN_LEN+i] = |
- (ghash->cLen >> ((GCM_HASH_LEN_LEN-1-i)*PR_BITS_PER_BYTE)) & 0xff; |
- } |
- ghash->cLen = 0; |
- |
- /* now zero fill the buffer and hash the last block */ |
- if (ghash->bufLen) { |
- PORT_Memset(ghash->buffer+ghash->bufLen, 0, blocksize - ghash->bufLen); |
- rv = gcm_HashMult(ghash, ghash->buffer, 1, blocksize); |
- PORT_Memset(ghash->buffer, 0, blocksize); |
- ghash->bufLen = 0; |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- } |
- return SECSuccess; |
-} |
- |
-/* |
- * This does the final sync, hashes the lengths, then returns |
- * "T", the hashed output. |
- */ |
-static SECStatus |
-gcmHash_Final(gcmHashContext *ghash, unsigned char *outbuf, |
- unsigned int *outlen, unsigned int maxout, |
- unsigned int blocksize) |
-{ |
- unsigned char T[MAX_BLOCK_SIZE]; |
- SECStatus rv; |
- |
- rv = gcmHash_Sync(ghash, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- |
- rv = gcm_HashMult(ghash, ghash->counterBuf, (GCM_HASH_LEN_LEN*2)/blocksize, |
- blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- |
- GCM_TRACE_X(ghash, "GHASH(H,A,C) = ") |
- |
- rv = gcm_getX(ghash, T, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- |
- if (maxout > blocksize) maxout = blocksize; |
- PORT_Memcpy(outbuf, T, maxout); |
- *outlen = maxout; |
- return SECSuccess; |
-} |
- |
-SECStatus |
-gcmHash_Reset(gcmHashContext *ghash, const unsigned char *AAD, |
- unsigned int AADLen, unsigned int blocksize) |
-{ |
- SECStatus rv; |
- |
- ghash->cLen = 0; |
- PORT_Memset(ghash->counterBuf, 0, GCM_HASH_LEN_LEN*2); |
- ghash->bufLen = 0; |
- gcm_zeroX(ghash); |
- |
- /* now kick things off by hashing the Additional Authenticated Data */ |
- if (AADLen != 0) { |
- rv = gcmHash_Update(ghash, AAD, AADLen, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- } |
- rv = gcmHash_Sync(ghash, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- return SECSuccess; |
-} |
- |
-/************************************************************************** |
- * Now implement the GCM using gcmHash and CTR * |
- **************************************************************************/ |
- |
-/* state to handle the full GCM operation (hash and counter) */ |
-struct GCMContextStr { |
- gcmHashContext ghash_context; |
- CTRContext ctr_context; |
- unsigned long tagBits; |
- unsigned char tagKey[MAX_BLOCK_SIZE]; |
-}; |
- |
-GCMContext * |
-GCM_CreateContext(void *context, freeblCipherFunc cipher, |
- const unsigned char *params, unsigned int blocksize) |
-{ |
- GCMContext *gcm = NULL; |
- gcmHashContext *ghash; |
- unsigned char H[MAX_BLOCK_SIZE]; |
- unsigned int tmp; |
- PRBool freeCtr = PR_FALSE; |
- PRBool freeHash = PR_FALSE; |
- const CK_GCM_PARAMS *gcmParams = (const CK_GCM_PARAMS *)params; |
- CK_AES_CTR_PARAMS ctrParams; |
- SECStatus rv; |
- |
- if (blocksize > MAX_BLOCK_SIZE || blocksize > sizeof(ctrParams.cb)) { |
- PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); |
- return NULL; |
- } |
- gcm = PORT_ZNew(GCMContext); |
- if (gcm == NULL) { |
- return NULL; |
- } |
- /* first fill in the ghash context */ |
- ghash = &gcm->ghash_context; |
- PORT_Memset(H, 0, blocksize); |
- rv = (*cipher)(context, H, &tmp, blocksize, H, blocksize, blocksize); |
- if (rv != SECSuccess) { |
- goto loser; |
- } |
- rv = gcmHash_InitContext(ghash, H, blocksize); |
- if (rv != SECSuccess) { |
- goto loser; |
- } |
- freeHash = PR_TRUE; |
- |
- /* fill in the Counter context */ |
- ctrParams.ulCounterBits = 32; |
- PORT_Memset(ctrParams.cb, 0, sizeof(ctrParams.cb)); |
- if ((blocksize == 16) && (gcmParams->ulIvLen == 12)) { |
- PORT_Memcpy(ctrParams.cb, gcmParams->pIv, gcmParams->ulIvLen); |
- ctrParams.cb[blocksize-1] = 1; |
- } else { |
- rv = gcmHash_Update(ghash, gcmParams->pIv, gcmParams->ulIvLen, |
- blocksize); |
- if (rv != SECSuccess) { |
- goto loser; |
- } |
- rv = gcmHash_Final(ghash, ctrParams.cb, &tmp, blocksize, blocksize); |
- if (rv != SECSuccess) { |
- goto loser; |
- } |
- } |
- rv = CTR_InitContext(&gcm->ctr_context, context, cipher, |
- (unsigned char *)&ctrParams, blocksize); |
- if (rv != SECSuccess) { |
- goto loser; |
- } |
- freeCtr = PR_TRUE; |
- |
- /* fill in the gcm structure */ |
- gcm->tagBits = gcmParams->ulTagBits; /* save for final step */ |
- /* calculate the final tag key. NOTE: gcm->tagKey is zero to start with. |
- * if this assumption changes, we would need to explicitly clear it here */ |
- rv = CTR_Update(&gcm->ctr_context, gcm->tagKey, &tmp, blocksize, |
- gcm->tagKey, blocksize, blocksize); |
- if (rv != SECSuccess) { |
- goto loser; |
- } |
- |
- /* finally mix in the AAD data */ |
- rv = gcmHash_Reset(ghash, gcmParams->pAAD, gcmParams->ulAADLen, blocksize); |
- if (rv != SECSuccess) { |
- goto loser; |
- } |
- |
- return gcm; |
- |
-loser: |
- if (freeCtr) { |
- CTR_DestroyContext(&gcm->ctr_context, PR_FALSE); |
- } |
- if (freeHash) { |
- gcmHash_DestroyContext(&gcm->ghash_context, PR_FALSE); |
- } |
- if (gcm) { |
- PORT_Free(gcm); |
- } |
- return NULL; |
-} |
- |
-void |
-GCM_DestroyContext(GCMContext *gcm, PRBool freeit) |
-{ |
- /* these two are statically allocated and will be freed when we free |
- * gcm. call their destroy functions to free up any locally |
- * allocated data (like mp_int's) */ |
- CTR_DestroyContext(&gcm->ctr_context, PR_FALSE); |
- gcmHash_DestroyContext(&gcm->ghash_context, PR_FALSE); |
- if (freeit) { |
- PORT_Free(gcm); |
- } |
-} |
- |
-static SECStatus |
-gcm_GetTag(GCMContext *gcm, unsigned char *outbuf, |
- unsigned int *outlen, unsigned int maxout, |
- unsigned int blocksize) |
-{ |
- unsigned int tagBytes; |
- unsigned int extra; |
- unsigned int i; |
- SECStatus rv; |
- |
- tagBytes = (gcm->tagBits + (PR_BITS_PER_BYTE-1)) / PR_BITS_PER_BYTE; |
- extra = tagBytes*PR_BITS_PER_BYTE - gcm->tagBits; |
- |
- if (outbuf == NULL) { |
- *outlen = tagBytes; |
- PORT_SetError(SEC_ERROR_OUTPUT_LEN); |
- return SECFailure; |
- } |
- |
- if (maxout < tagBytes) { |
- *outlen = tagBytes; |
- PORT_SetError(SEC_ERROR_OUTPUT_LEN); |
- return SECFailure; |
- } |
- maxout = tagBytes; |
- rv = gcmHash_Final(&gcm->ghash_context, outbuf, outlen, maxout, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- |
- GCM_TRACE_BLOCK("GHASH=", outbuf, blocksize); |
- GCM_TRACE_BLOCK("Y0=", gcm->tagKey, blocksize); |
- for (i=0; i < *outlen; i++) { |
- outbuf[i] ^= gcm->tagKey[i]; |
- } |
- GCM_TRACE_BLOCK("Y0=", gcm->tagKey, blocksize); |
- GCM_TRACE_BLOCK("T=", outbuf, blocksize); |
- /* mask off any extra bits we got */ |
- if (extra) { |
- outbuf[tagBytes-1] &= ~((1 << extra)-1); |
- } |
- return SECSuccess; |
-} |
- |
- |
-/* |
- * See The Galois/Counter Mode of Operation, McGrew and Viega. |
- * GCM is basically counter mode with a specific initialization and |
- * built in macing operation. |
- */ |
-SECStatus |
-GCM_EncryptUpdate(GCMContext *gcm, unsigned char *outbuf, |
- unsigned int *outlen, unsigned int maxout, |
- const unsigned char *inbuf, unsigned int inlen, |
- unsigned int blocksize) |
-{ |
- SECStatus rv; |
- unsigned int tagBytes; |
- unsigned int len; |
- |
- tagBytes = (gcm->tagBits + (PR_BITS_PER_BYTE-1)) / PR_BITS_PER_BYTE; |
- if (UINT_MAX - inlen < tagBytes) { |
- PORT_SetError(SEC_ERROR_INPUT_LEN); |
- return SECFailure; |
- } |
- if (maxout < inlen + tagBytes) { |
- *outlen = inlen + tagBytes; |
- PORT_SetError(SEC_ERROR_OUTPUT_LEN); |
- return SECFailure; |
- } |
- |
- rv = CTR_Update(&gcm->ctr_context, outbuf, outlen, maxout, |
- inbuf, inlen, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- rv = gcmHash_Update(&gcm->ghash_context, outbuf, *outlen, blocksize); |
- if (rv != SECSuccess) { |
- PORT_Memset(outbuf, 0, *outlen); /* clear the output buffer */ |
- *outlen = 0; |
- return SECFailure; |
- } |
- rv = gcm_GetTag(gcm, outbuf + *outlen, &len, maxout - *outlen, blocksize); |
- if (rv != SECSuccess) { |
- PORT_Memset(outbuf, 0, *outlen); /* clear the output buffer */ |
- *outlen = 0; |
- return SECFailure; |
- }; |
- *outlen += len; |
- return SECSuccess; |
-} |
- |
-/* |
- * See The Galois/Counter Mode of Operation, McGrew and Viega. |
- * GCM is basically counter mode with a specific initialization and |
- * built in macing operation. NOTE: the only difference between Encrypt |
- * and Decrypt is when we calculate the mac. That is because the mac must |
- * always be calculated on the cipher text, not the plain text, so for |
- * encrypt, we do the CTR update first and for decrypt we do the mac first. |
- */ |
-SECStatus |
-GCM_DecryptUpdate(GCMContext *gcm, unsigned char *outbuf, |
- unsigned int *outlen, unsigned int maxout, |
- const unsigned char *inbuf, unsigned int inlen, |
- unsigned int blocksize) |
-{ |
- SECStatus rv; |
- unsigned int tagBytes; |
- unsigned char tag[MAX_BLOCK_SIZE]; |
- const unsigned char *intag; |
- unsigned int len; |
- |
- tagBytes = (gcm->tagBits + (PR_BITS_PER_BYTE-1)) / PR_BITS_PER_BYTE; |
- |
- /* get the authentication block */ |
- if (inlen < tagBytes) { |
- PORT_SetError(SEC_ERROR_INPUT_LEN); |
- return SECFailure; |
- } |
- |
- inlen -= tagBytes; |
- intag = inbuf + inlen; |
- |
- /* verify the block */ |
- rv = gcmHash_Update(&gcm->ghash_context, inbuf, inlen, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- rv = gcm_GetTag(gcm, tag, &len, blocksize, blocksize); |
- if (rv != SECSuccess) { |
- return SECFailure; |
- } |
- /* Don't decrypt if we can't authenticate the encrypted data! |
- * This assumes that if tagBits is not a multiple of 8, intag will |
- * preserve the masked off missing bits. */ |
- if (NSS_SecureMemcmp(tag, intag, tagBytes) != 0) { |
- /* force a CKR_ENCRYPTED_DATA_INVALID error at in softoken */ |
- PORT_SetError(SEC_ERROR_BAD_DATA); |
- return SECFailure; |
- } |
- /* finish the decryption */ |
- return CTR_Update(&gcm->ctr_context, outbuf, outlen, maxout, |
- inbuf, inlen, blocksize); |
-} |