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/* 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
/* Thanks to Thomas Pornin for the ideas how to implement the constat time
* binary multiplication. */
#ifdef FREEBL_NO_DEPEND
#include "stubs.h"
#endif
#include "blapii.h"
#include "blapit.h"
#include "blapi.h"
#include "gcm.h"
#include "ctr.h"
#include "secerr.h"
#include "prtypes.h"
#include "pkcs11t.h"
#include <limits.h>
/* old gcc doesn't support some poly64x2_t intrinsic */
#if defined(__aarch64__) && defined(IS_LITTLE_ENDIAN) && \
(defined(__clang__) || defined(__GNUC__) && __GNUC__ > 6)
#define USE_ARM_GCM
#elif defined(__arm__) && defined(IS_LITTLE_ENDIAN) && \
!defined(NSS_DISABLE_ARM32_NEON)
/* We don't test on big endian platform, so disable this on big endian. */
#define USE_ARM_GCM
#endif
/* Forward declarations */
SECStatus gcm_HashInit_hw(gcmHashContext *ghash);
SECStatus gcm_HashWrite_hw(gcmHashContext *ghash, unsigned char *outbuf);
SECStatus gcm_HashMult_hw(gcmHashContext *ghash, const unsigned char *buf,
unsigned int count);
SECStatus gcm_HashZeroX_hw(gcmHashContext *ghash);
SECStatus gcm_HashMult_sftw(gcmHashContext *ghash, const unsigned char *buf,
unsigned int count);
SECStatus gcm_HashMult_sftw32(gcmHashContext *ghash, const unsigned char *buf,
unsigned int count);
/* Stub definitions for the above *_hw functions, which shouldn't be
* used unless NSS_X86_OR_X64 is defined */
#if !defined(NSS_X86_OR_X64) && !defined(USE_ARM_GCM) && !defined(USE_PPC_CRYPTO)
SECStatus
gcm_HashWrite_hw(gcmHashContext *ghash, unsigned char *outbuf)
{
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
SECStatus
gcm_HashMult_hw(gcmHashContext *ghash, const unsigned char *buf,
unsigned int count)
{
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
SECStatus
gcm_HashInit_hw(gcmHashContext *ghash)
{
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
SECStatus
gcm_HashZeroX_hw(gcmHashContext *ghash)
{
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
#endif /* !NSS_X86_OR_X64 && !USE_ARM_GCM && !USE_PPC_CRYPTO */
uint64_t
get64(const unsigned char *bytes)
{
return ((uint64_t)bytes[0]) << 56 |
((uint64_t)bytes[1]) << 48 |
((uint64_t)bytes[2]) << 40 |
((uint64_t)bytes[3]) << 32 |
((uint64_t)bytes[4]) << 24 |
((uint64_t)bytes[5]) << 16 |
((uint64_t)bytes[6]) << 8 |
((uint64_t)bytes[7]);
}
/* Initialize a gcmHashContext */
SECStatus
gcmHash_InitContext(gcmHashContext *ghash, const unsigned char *H, PRBool sw)
{
SECStatus rv = SECSuccess;
ghash->cLen = 0;
ghash->bufLen = 0;
PORT_Memset(ghash->counterBuf, 0, sizeof(ghash->counterBuf));
ghash->h_low = get64(H + 8);
ghash->h_high = get64(H);
#ifdef USE_ARM_GCM
#if defined(__aarch64__)
if (arm_pmull_support() && !sw) {
#else
if (arm_neon_support() && !sw) {
#endif
#elif defined(USE_PPC_CRYPTO)
if (ppc_crypto_support() && !sw) {
#else
if (clmul_support() && !sw) {
#endif
rv = gcm_HashInit_hw(ghash);
} else {
/* We fall back to the software implementation if we can't use / don't
* want to use pclmul. */
#ifdef HAVE_INT128_SUPPORT
ghash->ghash_mul = gcm_HashMult_sftw;
#else
ghash->ghash_mul = gcm_HashMult_sftw32;
#endif
ghash->x_high = ghash->x_low = 0;
ghash->hw = PR_FALSE;
}
return rv;
}
#ifdef HAVE_INT128_SUPPORT
/* Binary multiplication x * y = r_high << 64 | r_low. */
void
bmul(uint64_t x, uint64_t y, uint64_t *r_high, uint64_t *r_low)
{
uint128_t x1, x2, x3, x4, x5;
uint128_t y1, y2, y3, y4, y5;
uint128_t r, z;
uint128_t m1 = (uint128_t)0x2108421084210842 << 64 | 0x1084210842108421;
uint128_t m2 = (uint128_t)0x4210842108421084 << 64 | 0x2108421084210842;
uint128_t m3 = (uint128_t)0x8421084210842108 << 64 | 0x4210842108421084;
uint128_t m4 = (uint128_t)0x0842108421084210 << 64 | 0x8421084210842108;
uint128_t m5 = (uint128_t)0x1084210842108421 << 64 | 0x0842108421084210;
x1 = x & m1;
y1 = y & m1;
x2 = x & m2;
y2 = y & m2;
x3 = x & m3;
y3 = y & m3;
x4 = x & m4;
y4 = y & m4;
x5 = x & m5;
y5 = y & m5;
z = (x1 * y1) ^ (x2 * y5) ^ (x3 * y4) ^ (x4 * y3) ^ (x5 * y2);
r = z & m1;
z = (x1 * y2) ^ (x2 * y1) ^ (x3 * y5) ^ (x4 * y4) ^ (x5 * y3);
r |= z & m2;
z = (x1 * y3) ^ (x2 * y2) ^ (x3 * y1) ^ (x4 * y5) ^ (x5 * y4);
r |= z & m3;
z = (x1 * y4) ^ (x2 * y3) ^ (x3 * y2) ^ (x4 * y1) ^ (x5 * y5);
r |= z & m4;
z = (x1 * y5) ^ (x2 * y4) ^ (x3 * y3) ^ (x4 * y2) ^ (x5 * y1);
r |= z & m5;
*r_high = (uint64_t)(r >> 64);
*r_low = (uint64_t)r;
}
SECStatus
gcm_HashMult_sftw(gcmHashContext *ghash, const unsigned char *buf,
unsigned int count)
{
uint64_t ci_low, ci_high;
size_t i;
uint64_t z2_low, z2_high, z0_low, z0_high, z1a_low, z1a_high;
uint128_t z_high = 0, z_low = 0;
ci_low = ghash->x_low;
ci_high = ghash->x_high;
for (i = 0; i < count; i++, buf += 16) {
ci_low ^= get64(buf + 8);
ci_high ^= get64(buf);
/* Do binary mult ghash->X = C * ghash->H (Karatsuba). */
bmul(ci_high, ghash->h_high, &z2_high, &z2_low);
bmul(ci_low, ghash->h_low, &z0_high, &z0_low);
bmul(ci_high ^ ci_low, ghash->h_high ^ ghash->h_low, &z1a_high, &z1a_low);
z1a_high ^= z2_high ^ z0_high;
z1a_low ^= z2_low ^ z0_low;
z_high = ((uint128_t)z2_high << 64) | (z2_low ^ z1a_high);
z_low = (((uint128_t)z0_high << 64) | z0_low) ^ (((uint128_t)z1a_low) << 64);
/* Shift one (multiply by x) as gcm spec is stupid. */
z_high = (z_high << 1) | (z_low >> 127);
z_low <<= 1;
/* Reduce */
z_low ^= (z_low << 127) ^ (z_low << 126) ^ (z_low << 121);
z_high ^= z_low ^ (z_low >> 1) ^ (z_low >> 2) ^ (z_low >> 7);
ci_low = (uint64_t)z_high;
ci_high = (uint64_t)(z_high >> 64);
}
ghash->x_low = ci_low;
ghash->x_high = ci_high;
return SECSuccess;
}
#else
/* Binary multiplication x * y = r_high << 32 | r_low. */
void
bmul32(uint32_t x, uint32_t y, uint32_t *r_high, uint32_t *r_low)
{
uint32_t x0, x1, x2, x3;
uint32_t y0, y1, y2, y3;
uint32_t m1 = (uint32_t)0x11111111;
uint32_t m2 = (uint32_t)0x22222222;
uint32_t m4 = (uint32_t)0x44444444;
uint32_t m8 = (uint32_t)0x88888888;
uint64_t z0, z1, z2, z3;
uint64_t z;
x0 = x & m1;
x1 = x & m2;
x2 = x & m4;
x3 = x & m8;
y0 = y & m1;
y1 = y & m2;
y2 = y & m4;
y3 = y & m8;
z0 = ((uint64_t)x0 * y0) ^ ((uint64_t)x1 * y3) ^
((uint64_t)x2 * y2) ^ ((uint64_t)x3 * y1);
z1 = ((uint64_t)x0 * y1) ^ ((uint64_t)x1 * y0) ^
((uint64_t)x2 * y3) ^ ((uint64_t)x3 * y2);
z2 = ((uint64_t)x0 * y2) ^ ((uint64_t)x1 * y1) ^
((uint64_t)x2 * y0) ^ ((uint64_t)x3 * y3);
z3 = ((uint64_t)x0 * y3) ^ ((uint64_t)x1 * y2) ^
((uint64_t)x2 * y1) ^ ((uint64_t)x3 * y0);
z0 &= ((uint64_t)m1 << 32) | m1;
z1 &= ((uint64_t)m2 << 32) | m2;
z2 &= ((uint64_t)m4 << 32) | m4;
z3 &= ((uint64_t)m8 << 32) | m8;
z = z0 | z1 | z2 | z3;
*r_high = (uint32_t)(z >> 32);
*r_low = (uint32_t)z;
}
SECStatus
gcm_HashMult_sftw32(gcmHashContext *ghash, const unsigned char *buf,
unsigned int count)
{
size_t i;
uint64_t ci_low, ci_high;
uint64_t z_high_h, z_high_l, z_low_h, z_low_l;
uint32_t ci_high_h, ci_high_l, ci_low_h, ci_low_l;
uint32_t b_a_h, b_a_l, a_a_h, a_a_l, b_b_h, b_b_l;
uint32_t a_b_h, a_b_l, b_c_h, b_c_l, a_c_h, a_c_l, c_c_h, c_c_l;
uint32_t ci_highXlow_h, ci_highXlow_l, c_a_h, c_a_l, c_b_h, c_b_l;
uint32_t h_high_h = (uint32_t)(ghash->h_high >> 32);
uint32_t h_high_l = (uint32_t)ghash->h_high;
uint32_t h_low_h = (uint32_t)(ghash->h_low >> 32);
uint32_t h_low_l = (uint32_t)ghash->h_low;
uint32_t h_highXlow_h = h_high_h ^ h_low_h;
uint32_t h_highXlow_l = h_high_l ^ h_low_l;
uint32_t h_highX_xored = h_highXlow_h ^ h_highXlow_l;
for (i = 0; i < count; i++, buf += 16) {
ci_low = ghash->x_low ^ get64(buf + 8);
ci_high = ghash->x_high ^ get64(buf);
ci_low_h = (uint32_t)(ci_low >> 32);
ci_low_l = (uint32_t)ci_low;
ci_high_h = (uint32_t)(ci_high >> 32);
ci_high_l = (uint32_t)ci_high;
ci_highXlow_h = ci_high_h ^ ci_low_h;
ci_highXlow_l = ci_high_l ^ ci_low_l;
/* Do binary mult ghash->X = C * ghash->H (recursive Karatsuba). */
bmul32(ci_high_h, h_high_h, &a_a_h, &a_a_l);
bmul32(ci_high_l, h_high_l, &a_b_h, &a_b_l);
bmul32(ci_high_h ^ ci_high_l, h_high_h ^ h_high_l, &a_c_h, &a_c_l);
a_c_h ^= a_a_h ^ a_b_h;
a_c_l ^= a_a_l ^ a_b_l;
a_a_l ^= a_c_h;
a_b_h ^= a_c_l;
/* ci_high * h_high = a_a_h:a_a_l:a_b_h:a_b_l */
bmul32(ci_low_h, h_low_h, &b_a_h, &b_a_l);
bmul32(ci_low_l, h_low_l, &b_b_h, &b_b_l);
bmul32(ci_low_h ^ ci_low_l, h_low_h ^ h_low_l, &b_c_h, &b_c_l);
b_c_h ^= b_a_h ^ b_b_h;
b_c_l ^= b_a_l ^ b_b_l;
b_a_l ^= b_c_h;
b_b_h ^= b_c_l;
/* ci_low * h_low = b_a_h:b_a_l:b_b_h:b_b_l */
bmul32(ci_highXlow_h, h_highXlow_h, &c_a_h, &c_a_l);
bmul32(ci_highXlow_l, h_highXlow_l, &c_b_h, &c_b_l);
bmul32(ci_highXlow_h ^ ci_highXlow_l, h_highX_xored, &c_c_h, &c_c_l);
c_c_h ^= c_a_h ^ c_b_h;
c_c_l ^= c_a_l ^ c_b_l;
c_a_l ^= c_c_h;
c_b_h ^= c_c_l;
/* (ci_high ^ ci_low) * (h_high ^ h_low) = c_a_h:c_a_l:c_b_h:c_b_l */
c_a_h ^= b_a_h ^ a_a_h;
c_a_l ^= b_a_l ^ a_a_l;
c_b_h ^= b_b_h ^ a_b_h;
c_b_l ^= b_b_l ^ a_b_l;
z_high_h = ((uint64_t)a_a_h << 32) | a_a_l;
z_high_l = (((uint64_t)a_b_h << 32) | a_b_l) ^
(((uint64_t)c_a_h << 32) | c_a_l);
z_low_h = (((uint64_t)b_a_h << 32) | b_a_l) ^
(((uint64_t)c_b_h << 32) | c_b_l);
z_low_l = ((uint64_t)b_b_h << 32) | b_b_l;
/* Shift one (multiply by x) as gcm spec is stupid. */
z_high_h = z_high_h << 1 | z_high_l >> 63;
z_high_l = z_high_l << 1 | z_low_h >> 63;
z_low_h = z_low_h << 1 | z_low_l >> 63;
z_low_l <<= 1;
/* Reduce */
z_low_h ^= (z_low_l << 63) ^ (z_low_l << 62) ^ (z_low_l << 57);
z_high_h ^= z_low_h ^ (z_low_h >> 1) ^ (z_low_h >> 2) ^ (z_low_h >> 7);
z_high_l ^= z_low_l ^ (z_low_l >> 1) ^ (z_low_l >> 2) ^ (z_low_l >> 7) ^
(z_low_h << 63) ^ (z_low_h << 62) ^ (z_low_h << 57);
ghash->x_high = z_high_h;
ghash->x_low = z_high_l;
}
return SECSuccess;
}
#endif /* HAVE_INT128_SUPPORT */
static SECStatus
gcm_zeroX(gcmHashContext *ghash)
{
SECStatus rv = SECSuccess;
if (ghash->hw) {
rv = gcm_HashZeroX_hw(ghash);
}
ghash->x_high = ghash->x_low = 0;
return rv;
}
/*
* implement GCM GHASH using the freebl GHASH function. The gcm_HashMult
* function always takes AES_BLOCK_SIZE lengths of data. gcmHash_Update will
* format the data properly.
*/
SECStatus
gcmHash_Update(gcmHashContext *ghash, const unsigned char *buf,
unsigned int len)
{
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, AES_BLOCK_SIZE - 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 == AES_BLOCK_SIZE);
/* hash the buffer and clear it */
rv = ghash->ghash_mul(ghash, ghash->buffer, 1);
PORT_Memset(ghash->buffer, 0, AES_BLOCK_SIZE);
ghash->bufLen = 0;
if (rv != SECSuccess) {
return SECFailure;
}
}
/* now hash any full blocks remaining in the data stream */
blocks = len / AES_BLOCK_SIZE;
if (blocks) {
rv = ghash->ghash_mul(ghash, buf, blocks);
if (rv != SECSuccess) {
return SECFailure;
}
buf += blocks * AES_BLOCK_SIZE;
len -= blocks * AES_BLOCK_SIZE;
}
/* 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)
{
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, AES_BLOCK_SIZE - ghash->bufLen);
rv = ghash->ghash_mul(ghash, ghash->buffer, 1);
PORT_Memset(ghash->buffer, 0, AES_BLOCK_SIZE);
ghash->bufLen = 0;
if (rv != SECSuccess) {
return SECFailure;
}
}
return SECSuccess;
}
#define WRITE64(x, bytes) \
(bytes)[0] = (x) >> 56; \
(bytes)[1] = (x) >> 48; \
(bytes)[2] = (x) >> 40; \
(bytes)[3] = (x) >> 32; \
(bytes)[4] = (x) >> 24; \
(bytes)[5] = (x) >> 16; \
(bytes)[6] = (x) >> 8; \
(bytes)[7] = (x);
/*
* This does the final sync, hashes the lengths, then returns
* "T", the hashed output.
*/
SECStatus
gcmHash_Final(gcmHashContext *ghash, unsigned char *outbuf,
unsigned int *outlen, unsigned int maxout)
{
unsigned char T[MAX_BLOCK_SIZE];
SECStatus rv;
rv = gcmHash_Sync(ghash);
if (rv != SECSuccess) {
goto cleanup;
}
rv = ghash->ghash_mul(ghash, ghash->counterBuf,
(GCM_HASH_LEN_LEN * 2) / AES_BLOCK_SIZE);
if (rv != SECSuccess) {
goto cleanup;
}
if (ghash->hw) {
rv = gcm_HashWrite_hw(ghash, T);
if (rv != SECSuccess) {
goto cleanup;
}
} else {
WRITE64(ghash->x_low, T + 8);
WRITE64(ghash->x_high, T);
}
if (maxout > AES_BLOCK_SIZE) {
maxout = AES_BLOCK_SIZE;
}
PORT_Memcpy(outbuf, T, maxout);
*outlen = maxout;
rv = SECSuccess;
cleanup:
PORT_Memset(T, 0, sizeof(T));
return rv;
}
SECStatus
gcmHash_Reset(gcmHashContext *ghash, const unsigned char *AAD,
unsigned int AADLen)
{
SECStatus rv;
// Limit AADLen in accordance with SP800-38D
if (sizeof(AADLen) >= 8) {
unsigned long long AADLen_ull = AADLen;
if (AADLen_ull > (1ULL << 61) - 1) {
PORT_SetError(SEC_ERROR_INPUT_LEN);
return SECFailure;
}
}
ghash->cLen = 0;
PORT_Memset(ghash->counterBuf, 0, GCM_HASH_LEN_LEN * 2);
ghash->bufLen = 0;
rv = gcm_zeroX(ghash);
if (rv != SECSuccess) {
return rv;
}
/* now kick things off by hashing the Additional Authenticated Data */
if (AADLen != 0) {
rv = gcmHash_Update(ghash, AAD, AADLen);
if (rv != SECSuccess) {
return SECFailure;
}
rv = gcmHash_Sync(ghash);
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;
freeblCipherFunc cipher;
void *cipher_context;
unsigned long tagBits;
unsigned char tagKey[MAX_BLOCK_SIZE];
PRBool ctr_context_init;
gcmIVContext gcm_iv;
};
SECStatus gcm_InitCounter(GCMContext *gcm, const unsigned char *iv,
unsigned int ivLen, unsigned int tagBits,
const unsigned char *aad, unsigned int aadLen);
GCMContext *
GCM_CreateContext(void *context, freeblCipherFunc cipher,
const unsigned char *params)
{
GCMContext *gcm = NULL;
gcmHashContext *ghash = NULL;
unsigned char H[MAX_BLOCK_SIZE];
unsigned int tmp;
const CK_NSS_GCM_PARAMS *gcmParams = (const CK_NSS_GCM_PARAMS *)params;
SECStatus rv;
#ifdef DISABLE_HW_GCM
const PRBool sw = PR_TRUE;
#else
const PRBool sw = PR_FALSE;
#endif
gcm = PORT_ZNew(GCMContext);
if (gcm == NULL) {
return NULL;
}
gcm->cipher = cipher;
gcm->cipher_context = context;
ghash = PORT_ZNewAligned(gcmHashContext, 16, mem);
/* first plug in the ghash context */
gcm->ghash_context = ghash;
PORT_Memset(H, 0, AES_BLOCK_SIZE);
rv = (*cipher)(context, H, &tmp, AES_BLOCK_SIZE, H, AES_BLOCK_SIZE, AES_BLOCK_SIZE);
if (rv != SECSuccess) {
goto loser;
}
rv = gcmHash_InitContext(ghash, H, sw);
if (rv != SECSuccess) {
goto loser;
}
gcm_InitIVContext(&gcm->gcm_iv);
gcm->ctr_context_init = PR_FALSE;
/* if gcmPara/ms is NULL, then we are creating an PKCS #11 MESSAGE
* style context, in which we initialize the key once, then do separate
* iv/aad's for each message. In that case we only initialize the key
* and ghash. We initialize the counter in each separate message */
if (gcmParams == NULL) {
/* OK we are finished with init, if we are doing MESSAGE interface,
* return from here */
return gcm;
}
rv = gcm_InitCounter(gcm, gcmParams->pIv, gcmParams->ulIvLen,
gcmParams->ulTagBits, gcmParams->pAAD,
gcmParams->ulAADLen);
if (rv != SECSuccess) {
goto loser;
}
PORT_Memset(H, 0, AES_BLOCK_SIZE);
gcm->ctr_context_init = PR_TRUE;
return gcm;
loser:
PORT_Memset(H, 0, AES_BLOCK_SIZE);
if (ghash && ghash->mem) {
void *mem = ghash->mem;
PORT_Memset(ghash, 0, sizeof(gcmHashContext));
PORT_Free(mem);
}
if (gcm) {
PORT_ZFree(gcm, sizeof(GCMContext));
}
return NULL;
}
SECStatus
gcm_InitCounter(GCMContext *gcm, const unsigned char *iv, unsigned int ivLen,
unsigned int tagBits, const unsigned char *aad,
unsigned int aadLen)
{
gcmHashContext *ghash = gcm->ghash_context;
unsigned int tmp;
PRBool freeCtr = PR_FALSE;
CK_AES_CTR_PARAMS ctrParams;
SECStatus rv;
/* Verify our parameters here */
if (ivLen == 0) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
goto loser;
}
if (tagBits != 128 && tagBits != 120 &&
tagBits != 112 && tagBits != 104 &&
tagBits != 96 && tagBits != 64 &&
tagBits != 32) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
goto loser;
}
/* fill in the Counter context */
ctrParams.ulCounterBits = 32;
PORT_Memset(ctrParams.cb, 0, sizeof(ctrParams.cb));
if (ivLen == 12) {
PORT_Memcpy(ctrParams.cb, iv, ivLen);
ctrParams.cb[AES_BLOCK_SIZE - 1] = 1;
} else {
rv = gcmHash_Reset(ghash, NULL, 0);
if (rv != SECSuccess) {
goto loser;
}
rv = gcmHash_Update(ghash, iv, ivLen);
if (rv != SECSuccess) {
goto loser;
}
rv = gcmHash_Final(ghash, ctrParams.cb, &tmp, AES_BLOCK_SIZE);
if (rv != SECSuccess) {
goto loser;
}
}
rv = CTR_InitContext(&gcm->ctr_context, gcm->cipher_context, gcm->cipher,
(unsigned char *)&ctrParams);
if (rv != SECSuccess) {
goto loser;
}
freeCtr = PR_TRUE;
/* fill in the gcm structure */
gcm->tagBits = tagBits; /* 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 */
PORT_Memset(gcm->tagKey, 0, sizeof(gcm->tagKey));
rv = CTR_Update(&gcm->ctr_context, gcm->tagKey, &tmp, AES_BLOCK_SIZE,
gcm->tagKey, AES_BLOCK_SIZE, AES_BLOCK_SIZE);
if (rv != SECSuccess) {
goto loser;
}
/* finally mix in the AAD data */
rv = gcmHash_Reset(ghash, aad, aadLen);
if (rv != SECSuccess) {
goto loser;
}
PORT_Memset(&ctrParams, 0, sizeof ctrParams);
return SECSuccess;
loser:
PORT_Memset(&ctrParams, 0, sizeof ctrParams);
if (freeCtr) {
CTR_DestroyContext(&gcm->ctr_context, PR_FALSE);
}
return SECFailure;
}
void
GCM_DestroyContext(GCMContext *gcm, PRBool freeit)
{
void *mem = gcm->ghash_context->mem;
/* ctr_context is 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) */
if (gcm->ctr_context_init) {
CTR_DestroyContext(&gcm->ctr_context, PR_FALSE);
}
PORT_Memset(gcm->ghash_context, 0, sizeof(gcmHashContext));
PORT_Free(mem);
PORT_Memset(&gcm->tagBits, 0, sizeof(gcm->tagBits));
PORT_Memset(gcm->tagKey, 0, sizeof(gcm->tagKey));
if (freeit) {
PORT_Free(gcm);
}
}
static SECStatus
gcm_GetTag(GCMContext *gcm, unsigned char *outbuf,
unsigned int *outlen, unsigned int maxout)
{
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);
if (rv != SECSuccess) {
return SECFailure;
}
for (i = 0; i < *outlen; i++) {
outbuf[i] ^= gcm->tagKey[i];
}
/* 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;
PORT_Assert(blocksize == AES_BLOCK_SIZE);
if (blocksize != AES_BLOCK_SIZE) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (!gcm->ctr_context_init) {
PORT_SetError(SEC_ERROR_NOT_INITIALIZED);
return SECFailure;
}
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, AES_BLOCK_SIZE);
if (rv != SECSuccess) {
return SECFailure;
}
rv = gcmHash_Update(gcm->ghash_context, outbuf, *outlen);
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);
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;
PORT_Assert(blocksize == AES_BLOCK_SIZE);
if (blocksize != AES_BLOCK_SIZE) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (!gcm->ctr_context_init) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
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);
if (rv != SECSuccess) {
return SECFailure;
}
rv = gcm_GetTag(gcm, tag, &len, AES_BLOCK_SIZE);
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);
PORT_Memset(tag, 0, sizeof(tag));
return SECFailure;
}
PORT_Memset(tag, 0, sizeof(tag));
/* finish the decryption */
return CTR_Update(&gcm->ctr_context, outbuf, outlen, maxout,
inbuf, inlen, AES_BLOCK_SIZE);
}
void
gcm_InitIVContext(gcmIVContext *gcmIv)
{
gcmIv->counter = 0;
gcmIv->max_count = 0;
gcmIv->ivGen = CKG_GENERATE;
gcmIv->ivLen = 0;
gcmIv->fixedBits = 0;
}
/*
* generate the IV on the fly and return it to the application.
* This function keeps a counter, which may be used in the IV
* generation, or may be used in simply to make sure we don't
* generate to many IV's from this same key.
* PKCS #11 defines 4 generating values:
* 1) CKG_NO_GENERATE: just use the passed in IV as it.
* 2) CKG_GENERATE: the application doesn't care what generation
* scheme is use (we default to counter in this code).
* 3) CKG_GENERATE_COUNTER: The IV is the value of a counter.
* 4) CKG_GENERATE_RANDOM: The IV is randomly generated.
* We add a fifth rule:
* 5) CKG_GENERATE_COUNTER_XOR: The Counter value is xor'ed with
* the IV.
* The value fixedBits specifies the number of bits that will be passed
* on from the original IV. The counter or the random data is is loaded
* in the remainder of the IV not covered by fixedBits, overwriting any
* data there. In the xor case the counter is xor'ed with the data in the
* IV. In all cases only bits outside of fixedBits is modified.
* The number of IV's we can generate is restricted by the size of the
* variable part of the IV and the generation algorithm used. Because of
* this, we require subsequent calls on this context to use the same
* generator, IV len, and fixed bits as the first call.
*/
SECStatus
gcm_GenerateIV(gcmIVContext *gcmIv, unsigned char *iv, unsigned int ivLen,
unsigned int fixedBits, CK_GENERATOR_FUNCTION ivGen)
{
unsigned int i;
unsigned int flexBits;
unsigned int ivOffset;
unsigned int ivNewCount;
unsigned char ivMask;
unsigned char ivSave;
SECStatus rv;
if (gcmIv->counter != 0) {
/* If we've already generated a message, make sure all subsequent
* messages are using the same generator */
if ((gcmIv->ivGen != ivGen) || (gcmIv->fixedBits != fixedBits) ||
(gcmIv->ivLen != ivLen)) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
} else {
/* remember these values */
gcmIv->ivGen = ivGen;
gcmIv->fixedBits = fixedBits;
gcmIv->ivLen = ivLen;
/* now calculate how may bits of IV we have to supply */
flexBits = ivLen * PR_BITS_PER_BYTE; /* bytes->bits */
/* first make sure we aren't going to overflow */
if (flexBits < fixedBits) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
flexBits -= fixedBits;
/* if we are generating a random number reduce the acceptable bits to
* avoid birthday attacks */
if (ivGen == CKG_GENERATE_RANDOM) {
if (flexBits <= GCMIV_RANDOM_BIRTHDAY_BITS) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
/* see freebl/blapit.h for how we calculate
* GCMIV_RANDOM_BIRTHDAY_BITS */
flexBits -= GCMIV_RANDOM_BIRTHDAY_BITS;
flexBits = flexBits >> 1;
}
if (flexBits == 0) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
/* Turn those bits into the number of IV's we can safely return */
if (flexBits >= sizeof(gcmIv->max_count) * PR_BITS_PER_BYTE) {
gcmIv->max_count = PR_UINT64(0xffffffffffffffff);
} else {
gcmIv->max_count = PR_UINT64(1) << flexBits;
}
}
/* no generate, accept the IV from the source */
if (ivGen == CKG_NO_GENERATE) {
gcmIv->counter = 1;
return SECSuccess;
}
/* make sure we haven't exceeded the number of IVs we can return
* for this key, generator, and IV size */
if (gcmIv->counter >= gcmIv->max_count) {
/* use a unique error from just bad user input */
PORT_SetError(SEC_ERROR_EXTRA_INPUT);
return SECFailure;
}
/* build to mask to handle the first byte of the IV */
ivOffset = fixedBits / PR_BITS_PER_BYTE;
ivMask = 0xff >> ((8 - (fixedBits & 7)) & 7);
ivNewCount = ivLen - ivOffset;
/* finally generate the IV */
switch (ivGen) {
case CKG_GENERATE: /* default to counter */
case CKG_GENERATE_COUNTER:
iv[ivOffset] = (iv[ivOffset] & ~ivMask) |
(PORT_GET_BYTE_BE(gcmIv->counter, 0, ivNewCount) & ivMask);
for (i = 1; i < ivNewCount; i++) {
iv[ivOffset + i] = PORT_GET_BYTE_BE(gcmIv->counter, i, ivNewCount);
}
break;
/* for TLS 1.3 */
case CKG_GENERATE_COUNTER_XOR:
iv[ivOffset] ^=
(PORT_GET_BYTE_BE(gcmIv->counter, 0, ivNewCount) & ivMask);
for (i = 1; i < ivNewCount; i++) {
iv[ivOffset + i] ^= PORT_GET_BYTE_BE(gcmIv->counter, i, ivNewCount);
}
break;
case CKG_GENERATE_RANDOM:
ivSave = iv[ivOffset] & ~ivMask;
rv = RNG_GenerateGlobalRandomBytes(iv + ivOffset, ivNewCount);
iv[ivOffset] = ivSave | (iv[ivOffset] & ivMask);
if (rv != SECSuccess) {
return rv;
}
break;
}
gcmIv->counter++;
return SECSuccess;
}
SECStatus
GCM_EncryptAEAD(GCMContext *gcm, unsigned char *outbuf,
unsigned int *outlen, unsigned int maxout,
const unsigned char *inbuf, unsigned int inlen,
void *params, unsigned int paramLen,
const unsigned char *aad, unsigned int aadLen,
unsigned int blocksize)
{
SECStatus rv;
unsigned int tagBytes;
unsigned int len;
const CK_GCM_MESSAGE_PARAMS *gcmParams =
(const CK_GCM_MESSAGE_PARAMS *)params;
PORT_Assert(blocksize == AES_BLOCK_SIZE);
if (blocksize != AES_BLOCK_SIZE) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* paramLen comes all the way from the application layer, make sure
* it's correct */
if (paramLen != sizeof(CK_GCM_MESSAGE_PARAMS)) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
/* if we were initialized with the C_EncryptInit, we shouldn't be in this
* function */
if (gcm->ctr_context_init) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (maxout < inlen) {
*outlen = inlen;
PORT_SetError(SEC_ERROR_OUTPUT_LEN);
return SECFailure;
}
rv = gcm_GenerateIV(&gcm->gcm_iv, gcmParams->pIv, gcmParams->ulIvLen,
gcmParams->ulIvFixedBits, gcmParams->ivGenerator);
if (rv != SECSuccess) {
return SECFailure;
}
rv = gcm_InitCounter(gcm, gcmParams->pIv, gcmParams->ulIvLen,
gcmParams->ulTagBits, aad, aadLen);
if (rv != SECSuccess) {
return SECFailure;
}
tagBytes = (gcm->tagBits + (PR_BITS_PER_BYTE - 1)) / PR_BITS_PER_BYTE;
rv = CTR_Update(&gcm->ctr_context, outbuf, outlen, maxout,
inbuf, inlen, AES_BLOCK_SIZE);
CTR_DestroyContext(&gcm->ctr_context, PR_FALSE);
if (rv != SECSuccess) {
return SECFailure;
}
rv = gcmHash_Update(gcm->ghash_context, outbuf, *outlen);
if (rv != SECSuccess) {
PORT_Memset(outbuf, 0, *outlen); /* clear the output buffer */
*outlen = 0;
return SECFailure;
}
rv = gcm_GetTag(gcm, gcmParams->pTag, &len, tagBytes);
if (rv != SECSuccess) {
PORT_Memset(outbuf, 0, *outlen); /* clear the output buffer */
*outlen = 0;
return SECFailure;
};
return SECSuccess;
}
SECStatus
GCM_DecryptAEAD(GCMContext *gcm, unsigned char *outbuf,
unsigned int *outlen, unsigned int maxout,
const unsigned char *inbuf, unsigned int inlen,
void *params, unsigned int paramLen,
const unsigned char *aad, unsigned int aadLen,
unsigned int blocksize)
{
SECStatus rv;
unsigned int tagBytes;
unsigned char tag[MAX_BLOCK_SIZE];
const unsigned char *intag;
unsigned int len;
const CK_GCM_MESSAGE_PARAMS *gcmParams =
(const CK_GCM_MESSAGE_PARAMS *)params;
PORT_Assert(blocksize == AES_BLOCK_SIZE);
if (blocksize != AES_BLOCK_SIZE) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* paramLen comes all the way from the application layer, make sure
* it's correct */
if (paramLen != sizeof(CK_GCM_MESSAGE_PARAMS)) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
/* if we were initialized with the C_DecryptInit, we shouldn't be in this
* function */
if (gcm->ctr_context_init) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (maxout < inlen) {
*outlen = inlen;
PORT_SetError(SEC_ERROR_OUTPUT_LEN);
return SECFailure;
}
rv = gcm_InitCounter(gcm, gcmParams->pIv, gcmParams->ulIvLen,
gcmParams->ulTagBits, aad, aadLen);
if (rv != SECSuccess) {
return SECFailure;
}
tagBytes = (gcm->tagBits + (PR_BITS_PER_BYTE - 1)) / PR_BITS_PER_BYTE;
intag = gcmParams->pTag;
PORT_Assert(tagBytes != 0);
/* verify the block */
rv = gcmHash_Update(gcm->ghash_context, inbuf, inlen);
if (rv != SECSuccess) {
CTR_DestroyContext(&gcm->ctr_context, PR_FALSE);
return SECFailure;
}
rv = gcm_GetTag(gcm, tag, &len, AES_BLOCK_SIZE);
if (rv != SECSuccess) {
CTR_DestroyContext(&gcm->ctr_context, PR_FALSE);
return SECFailure;
}
/* Don't decrypt if we can't authenticate the encrypted data!
* This assumes that if tagBits is may not be 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 */
CTR_DestroyContext(&gcm->ctr_context, PR_FALSE);
PORT_SetError(SEC_ERROR_BAD_DATA);
PORT_Memset(tag, 0, sizeof(tag));
return SECFailure;
}
PORT_Memset(tag, 0, sizeof(tag));
/* finish the decryption */
rv = CTR_Update(&gcm->ctr_context, outbuf, outlen, maxout,
inbuf, inlen, AES_BLOCK_SIZE);
CTR_DestroyContext(&gcm->ctr_context, PR_FALSE);
return rv;
}