#ifndef OPENSSL_NO_OCB
-union ublock {
- unsigned char *chrblk;
- OCB_BLOCK *ocbblk;
-};
-
/*
* Calculate the number of binary trailing zero's in any given number
*/
/*
* Shift a block of 16 bytes left by shift bits
*/
-static void ocb_block_lshift(OCB_BLOCK *in, size_t shift, OCB_BLOCK *out)
+static void ocb_block_lshift(const unsigned char *in, size_t shift,
+ unsigned char *out)
{
unsigned char shift_mask;
int i;
unsigned char mask[15];
- union ublock locin;
- union ublock locout;
-
- locin.ocbblk = in;
- locout.ocbblk = out;
shift_mask = 0xff;
shift_mask <<= (8 - shift);
for (i = 15; i >= 0; i--) {
if (i > 0) {
- mask[i - 1] = locin.chrblk[i] & shift_mask;
+ mask[i - 1] = in[i] & shift_mask;
mask[i - 1] >>= 8 - shift;
}
- locout.chrblk[i] = locin.chrblk[i] << shift;
+ out[i] = in[i] << shift;
if (i != 15) {
- locout.chrblk[i] ^= mask[i];
+ out[i] ^= mask[i];
}
}
}
static void ocb_double(OCB_BLOCK *in, OCB_BLOCK *out)
{
unsigned char mask;
- union ublock locin;
- union ublock locout;
-
- locin.ocbblk = in;
- locout.ocbblk = out;
/*
* Calculate the mask based on the most significant bit. There are more
* efficient ways to do this - but this way is constant time
*/
- mask = locin.chrblk[0] & 0x80;
+ mask = in->c[0] & 0x80;
mask >>= 7;
mask *= 135;
- ocb_block_lshift(in, 1, out);
+ ocb_block_lshift(in->c, 1, out->c);
- locout.chrblk[15] ^= mask;
+ out->c[15] ^= mask;
}
/*
*/
static OCB_BLOCK *ocb_lookup_l(OCB128_CONTEXT *ctx, size_t idx)
{
- if (idx <= ctx->l_index) {
+ size_t l_index = ctx->l_index;
+
+ if (idx <= l_index) {
return ctx->l + idx;
}
/* We don't have it - so calculate it */
- ctx->l_index++;
- if (ctx->l_index == ctx->max_l_index) {
- ctx->max_l_index *= 2;
+ if (idx >= ctx->max_l_index) {
+ /*
+ * Each additional entry allows to process almost double as
+ * much data, so that in linear world the table will need to
+ * be expanded with smaller and smaller increments. Originally
+ * it was doubling in size, which was a waste. Growing it
+ * linearly is not formally optimal, but is simpler to implement.
+ * We grow table by minimally required 4*n that would accommodate
+ * the index.
+ */
+ ctx->max_l_index += (idx - ctx->max_l_index + 4) & ~3;
ctx->l =
OPENSSL_realloc(ctx->l, ctx->max_l_index * sizeof(OCB_BLOCK));
if (!ctx->l)
return NULL;
}
- ocb_double(ctx->l + (idx - 1), ctx->l + idx);
+ while (l_index < idx) {
+ ocb_double(ctx->l + l_index, ctx->l + l_index + 1);
+ l_index++;
+ }
+ ctx->l_index = l_index;
return ctx->l + idx;
}
static void ocb_encrypt(OCB128_CONTEXT *ctx, OCB_BLOCK *in, OCB_BLOCK *out,
void *keyenc)
{
- union ublock locin;
- union ublock locout;
-
- locin.ocbblk = in;
- locout.ocbblk = out;
-
- ctx->encrypt(locin.chrblk, locout.chrblk, keyenc);
+ ctx->encrypt(in->c, out->c, keyenc);
}
/*
static void ocb_decrypt(OCB128_CONTEXT *ctx, OCB_BLOCK *in, OCB_BLOCK *out,
void *keydec)
{
- union ublock locin;
- union ublock locout;
-
- locin.ocbblk = in;
- locout.ocbblk = out;
-
- ctx->decrypt(locin.chrblk, locout.chrblk, keydec);
+ ctx->decrypt(in->c, out->c, keydec);
}
/*
OCB128_CONTEXT *octx;
int ret;
- if ((octx = (OCB128_CONTEXT *)OPENSSL_malloc(sizeof(OCB128_CONTEXT)))) {
+ if ((octx = OPENSSL_malloc(sizeof(*octx))) != NULL) {
ret = CRYPTO_ocb128_init(octx, keyenc, keydec, encrypt, decrypt);
if (ret)
return octx;
int CRYPTO_ocb128_init(OCB128_CONTEXT *ctx, void *keyenc, void *keydec,
block128_f encrypt, block128_f decrypt)
{
- /* Clear everything to NULLs */
memset(ctx, 0, sizeof(*ctx));
-
ctx->l_index = 0;
- ctx->max_l_index = 1;
+ ctx->max_l_index = 5;
ctx->l = OPENSSL_malloc(ctx->max_l_index * 16);
- if (!ctx->l)
+ if (ctx->l == NULL)
return 0;
/*
/* L_0 = double(L_$) */
ocb_double(&ctx->l_dollar, ctx->l);
+ /* L_{i} = double(L_{i-1}) */
+ ocb_double(ctx->l, ctx->l+1);
+ ocb_double(ctx->l+1, ctx->l+2);
+ ocb_double(ctx->l+2, ctx->l+3);
+ ocb_double(ctx->l+3, ctx->l+4);
+ ctx->l_index = 4; /* enough to process up to 496 bytes */
+
return 1;
}
dest->keydec = keydec;
if (src->l) {
dest->l = OPENSSL_malloc(src->max_l_index * 16);
- if (!dest->l)
+ if (dest->l == NULL)
return 0;
memcpy(dest->l, src->l, (src->l_index + 1) * 16);
}
unsigned char ktop[16], tmp[16], mask;
unsigned char stretch[24], nonce[16];
size_t bottom, shift;
- union ublock offset;
-
- offset.ocbblk = &ctx->offset;
/*
* Spec says IV is 120 bits or fewer - it allows non byte aligned lengths.
/* Offset_0 = Stretch[1+bottom..128+bottom] */
shift = bottom % 8;
- ocb_block_lshift((OCB_BLOCK *)(stretch + (bottom / 8)), shift,
- &ctx->offset);
+ ocb_block_lshift(stretch + (bottom / 8), shift, ctx->offset.c);
mask = 0xff;
mask <<= 8 - shift;
- offset.chrblk[15] |=
+ ctx->offset.c[15] |=
(*(stretch + (bottom / 8) + 16) & mask) >> (8 - shift);
return 1;
ocb_block16_xor(&ctx->offset_aad, &ctx->l_star, &ctx->offset_aad);
/* CipherInput = (A_* || 1 || zeros(127-bitlen(A_*))) xor Offset_* */
- memset((void *)&tmp1, 0, 16);
- memcpy((void *)&tmp1, aad + (num_blocks * 16), last_len);
+ memset(&tmp1, 0, 16);
+ memcpy(&tmp1, aad + (num_blocks * 16), last_len);
((unsigned char *)&tmp1)[last_len] = 0x80;
ocb_block16_xor(&ctx->offset_aad, &tmp1, &tmp2);
/* C_i = Offset_i xor ENCIPHER(K, P_i xor Offset_i) */
inblock = (OCB_BLOCK *)(in + ((i - ctx->blocks_processed - 1) * 16));
- ocb_block16_xor(&ctx->offset, inblock, &tmp1);
+ ocb_block16_xor_misaligned(&ctx->offset, inblock, &tmp1);
+ /* Checksum_i = Checksum_{i-1} xor P_i */
+ ocb_block16_xor_misaligned(&ctx->checksum, inblock, &ctx->checksum);
ocb_encrypt(ctx, &tmp1, &tmp2, ctx->keyenc);
outblock =
(OCB_BLOCK *)(out + ((i - ctx->blocks_processed - 1) * 16));
- ocb_block16_xor(&ctx->offset, &tmp2, outblock);
+ ocb_block16_xor_misaligned(&ctx->offset, &tmp2, outblock);
- /* Checksum_i = Checksum_{i-1} xor P_i */
- ocb_block16_xor(&ctx->checksum, inblock, &ctx->checksum);
}
/*
out + (num_blocks * 16));
/* Checksum_* = Checksum_m xor (P_* || 1 || zeros(127-bitlen(P_*))) */
- memset((void *)&tmp1, 0, 16);
- memcpy((void *)&tmp1, in + (len / 16) * 16, last_len);
+ memset(&tmp1, 0, 16);
+ memcpy(&tmp1, in + (len / 16) * 16, last_len);
((unsigned char *)(&tmp1))[last_len] = 0x80;
ocb_block16_xor(&ctx->checksum, &tmp1, &ctx->checksum);
}
/* P_i = Offset_i xor DECIPHER(K, C_i xor Offset_i) */
inblock = (OCB_BLOCK *)(in + ((i - ctx->blocks_processed - 1) * 16));
- ocb_block16_xor(&ctx->offset, inblock, &tmp1);
+ ocb_block16_xor_misaligned(&ctx->offset, inblock, &tmp1);
ocb_decrypt(ctx, &tmp1, &tmp2, ctx->keydec);
outblock =
(OCB_BLOCK *)(out + ((i - ctx->blocks_processed - 1) * 16));
- ocb_block16_xor(&ctx->offset, &tmp2, outblock);
+ ocb_block16_xor_misaligned(&ctx->offset, &tmp2, outblock);
/* Checksum_i = Checksum_{i-1} xor P_i */
- ocb_block16_xor(&ctx->checksum, outblock, &ctx->checksum);
+ ocb_block16_xor_misaligned(&ctx->checksum, outblock, &ctx->checksum);
}
/*
out + (num_blocks * 16));
/* Checksum_* = Checksum_m xor (P_* || 1 || zeros(127-bitlen(P_*))) */
- memset((void *)&tmp1, 0, 16);
- memcpy((void *)&tmp1, out + (len / 16) * 16, last_len);
+ memset(&tmp1, 0, 16);
+ memcpy(&tmp1, out + (len / 16) * 16, last_len);
((unsigned char *)(&tmp1))[last_len] = 0x80;
ocb_block16_xor(&ctx->checksum, &tmp1, &ctx->checksum);
}
void CRYPTO_ocb128_cleanup(OCB128_CONTEXT *ctx)
{
if (ctx) {
- if (ctx->l) {
- OPENSSL_cleanse(ctx->l, ctx->max_l_index * 16);
- OPENSSL_free(ctx->l);
- }
+ OPENSSL_clear_free(ctx->l, ctx->max_l_index * 16);
OPENSSL_cleanse(ctx, sizeof(*ctx));
}
}
projects / openssl.git / blobdiff