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-rw-r--r--crypto/rand/drbg_ctr.c200
1 files changed, 127 insertions, 73 deletions
diff --git a/crypto/rand/drbg_ctr.c b/crypto/rand/drbg_ctr.c
index 0f0ad1b37be4..a757d0a258ab 100644
--- a/crypto/rand/drbg_ctr.c
+++ b/crypto/rand/drbg_ctr.c
@@ -63,15 +63,15 @@ static void ctr_XOR(RAND_DRBG_CTR *ctr, const unsigned char *in, size_t inlen)
* Process a complete block using BCC algorithm of SP 800-90A 10.3.3
*/
__owur static int ctr_BCC_block(RAND_DRBG_CTR *ctr, unsigned char *out,
- const unsigned char *in)
+ const unsigned char *in, int len)
{
int i, outlen = AES_BLOCK_SIZE;
- for (i = 0; i < 16; i++)
+ for (i = 0; i < len; i++)
out[i] ^= in[i];
- if (!EVP_CipherUpdate(ctr->ctx_df, out, &outlen, out, AES_BLOCK_SIZE)
- || outlen != AES_BLOCK_SIZE)
+ if (!EVP_CipherUpdate(ctr->ctx_df, out, &outlen, out, len)
+ || outlen != len)
return 0;
return 1;
}
@@ -82,12 +82,16 @@ __owur static int ctr_BCC_block(RAND_DRBG_CTR *ctr, unsigned char *out,
*/
__owur static int ctr_BCC_blocks(RAND_DRBG_CTR *ctr, const unsigned char *in)
{
- if (!ctr_BCC_block(ctr, ctr->KX, in)
- || !ctr_BCC_block(ctr, ctr->KX + 16, in))
- return 0;
- if (ctr->keylen != 16 && !ctr_BCC_block(ctr, ctr->KX + 32, in))
- return 0;
- return 1;
+ unsigned char in_tmp[48];
+ unsigned char num_of_blk = 2;
+
+ memcpy(in_tmp, in, 16);
+ memcpy(in_tmp + 16, in, 16);
+ if (ctr->keylen != 16) {
+ memcpy(in_tmp + 32, in, 16);
+ num_of_blk = 3;
+ }
+ return ctr_BCC_block(ctr, ctr->KX, in_tmp, AES_BLOCK_SIZE * num_of_blk);
}
/*
@@ -96,19 +100,14 @@ __owur static int ctr_BCC_blocks(RAND_DRBG_CTR *ctr, const unsigned char *in)
*/
__owur static int ctr_BCC_init(RAND_DRBG_CTR *ctr)
{
+ unsigned char bltmp[48] = {0};
+ unsigned char num_of_blk;
+
memset(ctr->KX, 0, 48);
- memset(ctr->bltmp, 0, 16);
- if (!ctr_BCC_block(ctr, ctr->KX, ctr->bltmp))
- return 0;
- ctr->bltmp[3] = 1;
- if (!ctr_BCC_block(ctr, ctr->KX + 16, ctr->bltmp))
- return 0;
- if (ctr->keylen != 16) {
- ctr->bltmp[3] = 2;
- if (!ctr_BCC_block(ctr, ctr->KX + 32, ctr->bltmp))
- return 0;
- }
- return 1;
+ num_of_blk = ctr->keylen == 16 ? 2 : 3;
+ bltmp[(AES_BLOCK_SIZE * 1) + 3] = 1;
+ bltmp[(AES_BLOCK_SIZE * 2) + 3] = 2;
+ return ctr_BCC_block(ctr, ctr->KX, bltmp, num_of_blk * AES_BLOCK_SIZE);
}
/*
@@ -197,20 +196,20 @@ __owur static int ctr_df(RAND_DRBG_CTR *ctr,
|| !ctr_BCC_final(ctr))
return 0;
/* Set up key K */
- if (!EVP_CipherInit_ex(ctr->ctx, ctr->cipher, NULL, ctr->KX, NULL, 1))
+ if (!EVP_CipherInit_ex(ctr->ctx_ecb, NULL, NULL, ctr->KX, NULL, -1))
return 0;
/* X follows key K */
- if (!EVP_CipherUpdate(ctr->ctx, ctr->KX, &outlen, ctr->KX + ctr->keylen,
+ if (!EVP_CipherUpdate(ctr->ctx_ecb, ctr->KX, &outlen, ctr->KX + ctr->keylen,
AES_BLOCK_SIZE)
|| outlen != AES_BLOCK_SIZE)
return 0;
- if (!EVP_CipherUpdate(ctr->ctx, ctr->KX + 16, &outlen, ctr->KX,
+ if (!EVP_CipherUpdate(ctr->ctx_ecb, ctr->KX + 16, &outlen, ctr->KX,
AES_BLOCK_SIZE)
|| outlen != AES_BLOCK_SIZE)
return 0;
if (ctr->keylen != 16)
- if (!EVP_CipherUpdate(ctr->ctx, ctr->KX + 32, &outlen, ctr->KX + 16,
- AES_BLOCK_SIZE)
+ if (!EVP_CipherUpdate(ctr->ctx_ecb, ctr->KX + 32, &outlen,
+ ctr->KX + 16, AES_BLOCK_SIZE)
|| outlen != AES_BLOCK_SIZE)
return 0;
return 1;
@@ -229,31 +228,25 @@ __owur static int ctr_update(RAND_DRBG *drbg,
{
RAND_DRBG_CTR *ctr = &drbg->data.ctr;
int outlen = AES_BLOCK_SIZE;
+ unsigned char V_tmp[48], out[48];
+ unsigned char len;
/* correct key is already set up. */
+ memcpy(V_tmp, ctr->V, 16);
inc_128(ctr);
- if (!EVP_CipherUpdate(ctr->ctx, ctr->K, &outlen, ctr->V, AES_BLOCK_SIZE)
- || outlen != AES_BLOCK_SIZE)
- return 0;
-
- /* If keylen longer than 128 bits need extra encrypt */
- if (ctr->keylen != 16) {
+ memcpy(V_tmp + 16, ctr->V, 16);
+ if (ctr->keylen == 16) {
+ len = 32;
+ } else {
inc_128(ctr);
- if (!EVP_CipherUpdate(ctr->ctx, ctr->K+16, &outlen, ctr->V,
- AES_BLOCK_SIZE)
- || outlen != AES_BLOCK_SIZE)
- return 0;
+ memcpy(V_tmp + 32, ctr->V, 16);
+ len = 48;
}
- inc_128(ctr);
- if (!EVP_CipherUpdate(ctr->ctx, ctr->V, &outlen, ctr->V, AES_BLOCK_SIZE)
- || outlen != AES_BLOCK_SIZE)
+ if (!EVP_CipherUpdate(ctr->ctx_ecb, out, &outlen, V_tmp, len)
+ || outlen != len)
return 0;
-
- /* If 192 bit key part of V is on end of K */
- if (ctr->keylen == 24) {
- memcpy(ctr->V + 8, ctr->V, 8);
- memcpy(ctr->V, ctr->K + 24, 8);
- }
+ memcpy(ctr->K, out, ctr->keylen);
+ memcpy(ctr->V, out + ctr->keylen, 16);
if ((drbg->flags & RAND_DRBG_FLAG_CTR_NO_DF) == 0) {
/* If no input reuse existing derived value */
@@ -268,7 +261,8 @@ __owur static int ctr_update(RAND_DRBG *drbg,
ctr_XOR(ctr, in2, in2len);
}
- if (!EVP_CipherInit_ex(ctr->ctx, ctr->cipher, NULL, ctr->K, NULL, 1))
+ if (!EVP_CipherInit_ex(ctr->ctx_ecb, NULL, NULL, ctr->K, NULL, -1)
+ || !EVP_CipherInit_ex(ctr->ctx_ctr, NULL, NULL, ctr->K, NULL, -1))
return 0;
return 1;
}
@@ -285,8 +279,10 @@ __owur static int drbg_ctr_instantiate(RAND_DRBG *drbg,
memset(ctr->K, 0, sizeof(ctr->K));
memset(ctr->V, 0, sizeof(ctr->V));
- if (!EVP_CipherInit_ex(ctr->ctx, ctr->cipher, NULL, ctr->K, NULL, 1))
+ if (!EVP_CipherInit_ex(ctr->ctx_ecb, NULL, NULL, ctr->K, NULL, -1))
return 0;
+
+ inc_128(ctr);
if (!ctr_update(drbg, entropy, entropylen, pers, perslen, nonce, noncelen))
return 0;
return 1;
@@ -296,20 +292,40 @@ __owur static int drbg_ctr_reseed(RAND_DRBG *drbg,
const unsigned char *entropy, size_t entropylen,
const unsigned char *adin, size_t adinlen)
{
+ RAND_DRBG_CTR *ctr = &drbg->data.ctr;
+
if (entropy == NULL)
return 0;
+
+ inc_128(ctr);
if (!ctr_update(drbg, entropy, entropylen, adin, adinlen, NULL, 0))
return 0;
return 1;
}
+static void ctr96_inc(unsigned char *counter)
+{
+ u32 n = 12, c = 1;
+
+ do {
+ --n;
+ c += counter[n];
+ counter[n] = (u8)c;
+ c >>= 8;
+ } while (n);
+}
+
__owur static int drbg_ctr_generate(RAND_DRBG *drbg,
unsigned char *out, size_t outlen,
const unsigned char *adin, size_t adinlen)
{
RAND_DRBG_CTR *ctr = &drbg->data.ctr;
+ unsigned int ctr32, blocks;
+ int outl, buflen;
if (adin != NULL && adinlen != 0) {
+ inc_128(ctr);
+
if (!ctr_update(drbg, adin, adinlen, NULL, 0, NULL, 0))
return 0;
/* This means we reuse derived value */
@@ -321,28 +337,53 @@ __owur static int drbg_ctr_generate(RAND_DRBG *drbg,
adinlen = 0;
}
- for ( ; ; ) {
- int outl = AES_BLOCK_SIZE;
+ inc_128(ctr);
+ if (outlen == 0) {
inc_128(ctr);
- if (outlen < 16) {
- /* Use K as temp space as it will be updated */
- if (!EVP_CipherUpdate(ctr->ctx, ctr->K, &outl, ctr->V,
- AES_BLOCK_SIZE)
- || outl != AES_BLOCK_SIZE)
- return 0;
- memcpy(out, ctr->K, outlen);
- break;
- }
- if (!EVP_CipherUpdate(ctr->ctx, out, &outl, ctr->V, AES_BLOCK_SIZE)
- || outl != AES_BLOCK_SIZE)
+
+ if (!ctr_update(drbg, adin, adinlen, NULL, 0, NULL, 0))
return 0;
- out += 16;
- outlen -= 16;
- if (outlen == 0)
- break;
+ return 1;
}
+ memset(out, 0, outlen);
+
+ do {
+ if (!EVP_CipherInit_ex(ctr->ctx_ctr,
+ NULL, NULL, NULL, ctr->V, -1))
+ return 0;
+
+ /*-
+ * outlen has type size_t while EVP_CipherUpdate takes an
+ * int argument and thus cannot be guaranteed to process more
+ * than 2^31-1 bytes at a time. We process such huge generate
+ * requests in 2^30 byte chunks, which is the greatest multiple
+ * of AES block size lower than or equal to 2^31-1.
+ */
+ buflen = outlen > (1U << 30) ? (1U << 30) : outlen;
+ blocks = (buflen + 15) / 16;
+
+ ctr32 = GETU32(ctr->V + 12) + blocks;
+ if (ctr32 < blocks) {
+ /* 32-bit counter overflow into V. */
+ if (ctr32 != 0) {
+ blocks -= ctr32;
+ buflen = blocks * 16;
+ ctr32 = 0;
+ }
+ ctr96_inc(ctr->V);
+ }
+ PUTU32(ctr->V + 12, ctr32);
+
+ if (!EVP_CipherUpdate(ctr->ctx_ctr, out, &outl, out, buflen)
+ || outl != buflen)
+ return 0;
+
+ out += buflen;
+ outlen -= buflen;
+ } while (outlen);
+
if (!ctr_update(drbg, adin, adinlen, NULL, 0, NULL, 0))
return 0;
return 1;
@@ -350,7 +391,8 @@ __owur static int drbg_ctr_generate(RAND_DRBG *drbg,
static int drbg_ctr_uninstantiate(RAND_DRBG *drbg)
{
- EVP_CIPHER_CTX_free(drbg->data.ctr.ctx);
+ EVP_CIPHER_CTX_free(drbg->data.ctr.ctx_ecb);
+ EVP_CIPHER_CTX_free(drbg->data.ctr.ctx_ctr);
EVP_CIPHER_CTX_free(drbg->data.ctr.ctx_df);
OPENSSL_cleanse(&drbg->data.ctr, sizeof(drbg->data.ctr));
return 1;
@@ -374,25 +416,36 @@ int drbg_ctr_init(RAND_DRBG *drbg)
return 0;
case NID_aes_128_ctr:
keylen = 16;
- ctr->cipher = EVP_aes_128_ecb();
+ ctr->cipher_ecb = EVP_aes_128_ecb();
+ ctr->cipher_ctr = EVP_aes_128_ctr();
break;
case NID_aes_192_ctr:
keylen = 24;
- ctr->cipher = EVP_aes_192_ecb();
+ ctr->cipher_ecb = EVP_aes_192_ecb();
+ ctr->cipher_ctr = EVP_aes_192_ctr();
break;
case NID_aes_256_ctr:
keylen = 32;
- ctr->cipher = EVP_aes_256_ecb();
+ ctr->cipher_ecb = EVP_aes_256_ecb();
+ ctr->cipher_ctr = EVP_aes_256_ctr();
break;
}
drbg->meth = &drbg_ctr_meth;
ctr->keylen = keylen;
- if (ctr->ctx == NULL)
- ctr->ctx = EVP_CIPHER_CTX_new();
- if (ctr->ctx == NULL)
+ if (ctr->ctx_ecb == NULL)
+ ctr->ctx_ecb = EVP_CIPHER_CTX_new();
+ if (ctr->ctx_ctr == NULL)
+ ctr->ctx_ctr = EVP_CIPHER_CTX_new();
+ if (ctr->ctx_ecb == NULL || ctr->ctx_ctr == NULL
+ || !EVP_CipherInit_ex(ctr->ctx_ecb,
+ ctr->cipher_ecb, NULL, NULL, NULL, 1)
+ || !EVP_CipherInit_ex(ctr->ctx_ctr,
+ ctr->cipher_ctr, NULL, NULL, NULL, 1))
return 0;
+
+ drbg->meth = &drbg_ctr_meth;
drbg->strength = keylen * 8;
drbg->seedlen = keylen + 16;
@@ -410,7 +463,8 @@ int drbg_ctr_init(RAND_DRBG *drbg)
if (ctr->ctx_df == NULL)
return 0;
/* Set key schedule for df_key */
- if (!EVP_CipherInit_ex(ctr->ctx_df, ctr->cipher, NULL, df_key, NULL, 1))
+ if (!EVP_CipherInit_ex(ctr->ctx_df,
+ ctr->cipher_ecb, NULL, df_key, NULL, 1))
return 0;
drbg->min_entropylen = ctr->keylen;