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Unified Diff: nss/lib/freebl/gcm.c

Issue 2078763002: Delete bundled copy of NSS and replace with README. (Closed) Base URL: https://chromium.googlesource.com/chromium/deps/nss@master
Patch Set: Delete bundled copy of NSS and replace with README. Created 4 years, 6 months ago
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Index: nss/lib/freebl/gcm.c
diff --git a/nss/lib/freebl/gcm.c b/nss/lib/freebl/gcm.c
deleted file mode 100644
index c8ba7383a11284044d937202e71898f2060a59e9..0000000000000000000000000000000000000000
--- a/nss/lib/freebl/gcm.c
+++ /dev/null
@@ -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);
-}
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