sha2: Write final hash directly to output buffer

This avoids having the last output in internal memory that's not wiped.

References #2388.
This commit is contained in:
Tobias Brunner
2017-08-07 16:55:33 +02:00
parent e0c78d7516
commit 1a75514b76
+26 -56
View File
@@ -226,7 +226,7 @@ static void sha256_write(private_sha256_hasher_t *ctx,
/** /**
* finalize SHA256 hash * finalize SHA256 hash
*/ */
static void sha256_final(private_sha256_hasher_t *ctx) static void sha256_final(private_sha256_hasher_t *ctx, u_char *buf, size_t len)
{ {
register int j; register int j;
uint64_t bitLength; uint64_t bitLength;
@@ -255,8 +255,7 @@ static void sha256_final(private_sha256_hasher_t *ctx)
ctx->sha_out[63] = bitLength; ctx->sha_out[63] = bitLength;
sha256_transform(ctx, &ctx->sha_out[0]); sha256_transform(ctx, &ctx->sha_out[0]);
/* return results in ctx->sha_out[0...31] */ datap = buf;
datap = &ctx->sha_out[0];
j = 0; j = 0;
do { do {
i = ctx->sha_H[j]; i = ctx->sha_H[j];
@@ -265,7 +264,7 @@ static void sha256_final(private_sha256_hasher_t *ctx)
datap[2] = i >> 8; datap[2] = i >> 8;
datap[3] = i; datap[3] = i;
datap += 4; datap += 4;
} while(++j < 8); } while(++j < len / 4);
} }
/* update macros for SHA512 */ /* update macros for SHA512 */
@@ -371,7 +370,7 @@ static void sha512_write(private_sha512_hasher_t *ctx,
/** /**
* Finalize a SHA384/SHA512 hash * Finalize a SHA384/SHA512 hash
*/ */
static void sha512_final(private_sha512_hasher_t *ctx) static void sha512_final(private_sha512_hasher_t *ctx, u_char *buf, size_t len)
{ {
register int j; register int j;
uint64_t bitLength, bitLengthMSB; uint64_t bitLength, bitLengthMSB;
@@ -409,8 +408,7 @@ static void sha512_final(private_sha512_hasher_t *ctx)
ctx->sha_out[127] = bitLength; ctx->sha_out[127] = bitLength;
sha512_transform(ctx, &ctx->sha_out[0]); sha512_transform(ctx, &ctx->sha_out[0]);
/* return results in ctx->sha_out[0...63] */ datap = buf;
datap = &ctx->sha_out[0];
j = 0; j = 0;
do { do {
i = ctx->sha_H[j]; i = ctx->sha_H[j];
@@ -423,7 +421,7 @@ static void sha512_final(private_sha512_hasher_t *ctx)
datap[6] = i >> 8; datap[6] = i >> 8;
datap[7] = i; datap[7] = i;
datap += 8; datap += 8;
} while(++j < 8); } while(++j < len / 8);
} }
METHOD(hasher_t, reset224, bool, METHOD(hasher_t, reset224, bool,
@@ -432,7 +430,6 @@ METHOD(hasher_t, reset224, bool,
memcpy(&this->sha_H[0], &sha224_hashInit[0], sizeof(this->sha_H)); memcpy(&this->sha_H[0], &sha224_hashInit[0], sizeof(this->sha_H));
this->sha_blocks = 0; this->sha_blocks = 0;
this->sha_bufCnt = 0; this->sha_bufCnt = 0;
return TRUE; return TRUE;
} }
@@ -442,7 +439,6 @@ METHOD(hasher_t, reset256, bool,
memcpy(&this->sha_H[0], &sha256_hashInit[0], sizeof(this->sha_H)); memcpy(&this->sha_H[0], &sha256_hashInit[0], sizeof(this->sha_H));
this->sha_blocks = 0; this->sha_blocks = 0;
this->sha_bufCnt = 0; this->sha_bufCnt = 0;
return TRUE; return TRUE;
} }
@@ -453,7 +449,6 @@ METHOD(hasher_t, reset384, bool,
this->sha_blocks = 0; this->sha_blocks = 0;
this->sha_blocksMSB = 0; this->sha_blocksMSB = 0;
this->sha_bufCnt = 0; this->sha_bufCnt = 0;
return TRUE; return TRUE;
} }
@@ -464,7 +459,6 @@ METHOD(hasher_t, reset512, bool,
this->sha_blocks = 0; this->sha_blocks = 0;
this->sha_blocksMSB = 0; this->sha_blocksMSB = 0;
this->sha_bufCnt = 0; this->sha_bufCnt = 0;
return TRUE; return TRUE;
} }
@@ -474,8 +468,7 @@ METHOD(hasher_t, get_hash224, bool,
sha256_write(this, chunk.ptr, chunk.len); sha256_write(this, chunk.ptr, chunk.len);
if (buffer != NULL) if (buffer != NULL)
{ {
sha256_final(this); sha256_final(this, buffer, HASH_SIZE_SHA224);
memcpy(buffer, this->sha_out, HASH_SIZE_SHA224);
reset224(this); reset224(this);
} }
return TRUE; return TRUE;
@@ -487,8 +480,7 @@ METHOD(hasher_t, get_hash256, bool,
sha256_write(this, chunk.ptr, chunk.len); sha256_write(this, chunk.ptr, chunk.len);
if (buffer != NULL) if (buffer != NULL)
{ {
sha256_final(this); sha256_final(this, buffer, HASH_SIZE_SHA256);
memcpy(buffer, this->sha_out, HASH_SIZE_SHA256);
reset256(this); reset256(this);
} }
return TRUE; return TRUE;
@@ -500,8 +492,7 @@ METHOD(hasher_t, get_hash384, bool,
sha512_write(this, chunk.ptr, chunk.len); sha512_write(this, chunk.ptr, chunk.len);
if (buffer != NULL) if (buffer != NULL)
{ {
sha512_final(this); sha512_final(this, buffer, HASH_SIZE_SHA384);
memcpy(buffer, this->sha_out, HASH_SIZE_SHA384);
reset384(this); reset384(this);
} }
return TRUE; return TRUE;
@@ -513,8 +504,7 @@ METHOD(hasher_t, get_hash512, bool,
sha512_write(this, chunk.ptr, chunk.len); sha512_write(this, chunk.ptr, chunk.len);
if (buffer != NULL) if (buffer != NULL)
{ {
sha512_final(this); sha512_final(this, buffer, HASH_SIZE_SHA512);
memcpy(buffer, this->sha_out, HASH_SIZE_SHA512);
reset512(this); reset512(this);
} }
return TRUE; return TRUE;
@@ -523,69 +513,49 @@ METHOD(hasher_t, get_hash512, bool,
METHOD(hasher_t, allocate_hash224, bool, METHOD(hasher_t, allocate_hash224, bool,
private_sha256_hasher_t *this, chunk_t chunk, chunk_t *hash) private_sha256_hasher_t *this, chunk_t chunk, chunk_t *hash)
{ {
chunk_t allocated_hash; chunk_t allocated_hash = chunk_empty;
sha256_write(this, chunk.ptr, chunk.len); if (hash)
if (hash != NULL)
{ {
sha256_final(this); *hash = allocated_hash = chunk_alloc(HASH_SIZE_SHA224);
allocated_hash = chunk_alloc(HASH_SIZE_SHA224);
memcpy(allocated_hash.ptr, this->sha_out, HASH_SIZE_SHA224);
reset224(this);
*hash = allocated_hash;
} }
return TRUE; return get_hash224(this, chunk, allocated_hash.ptr);
} }
METHOD(hasher_t, allocate_hash256, bool, METHOD(hasher_t, allocate_hash256, bool,
private_sha256_hasher_t *this, chunk_t chunk, chunk_t *hash) private_sha256_hasher_t *this, chunk_t chunk, chunk_t *hash)
{ {
chunk_t allocated_hash; chunk_t allocated_hash = chunk_empty;
sha256_write(this, chunk.ptr, chunk.len); if (hash)
if (hash != NULL)
{ {
sha256_final(this); *hash = allocated_hash = chunk_alloc(HASH_SIZE_SHA256);
allocated_hash = chunk_alloc(HASH_SIZE_SHA256);
memcpy(allocated_hash.ptr, this->sha_out, HASH_SIZE_SHA256);
reset256(this);
*hash = allocated_hash;
} }
return TRUE; return get_hash256(this, chunk, allocated_hash.ptr);
} }
METHOD(hasher_t, allocate_hash384, bool, METHOD(hasher_t, allocate_hash384, bool,
private_sha512_hasher_t *this, chunk_t chunk, chunk_t *hash) private_sha512_hasher_t *this, chunk_t chunk, chunk_t *hash)
{ {
chunk_t allocated_hash; chunk_t allocated_hash = chunk_empty;
sha512_write(this, chunk.ptr, chunk.len); if (hash)
if (hash != NULL)
{ {
sha512_final(this); *hash = allocated_hash = chunk_alloc(HASH_SIZE_SHA384);
allocated_hash = chunk_alloc(HASH_SIZE_SHA384);
memcpy(allocated_hash.ptr, this->sha_out, HASH_SIZE_SHA384);
reset384(this);
*hash = allocated_hash;
} }
return TRUE; return get_hash384(this, chunk, allocated_hash.ptr);
} }
METHOD(hasher_t, allocate_hash512, bool, METHOD(hasher_t, allocate_hash512, bool,
private_sha512_hasher_t *this, chunk_t chunk, chunk_t *hash) private_sha512_hasher_t *this, chunk_t chunk, chunk_t *hash)
{ {
chunk_t allocated_hash; chunk_t allocated_hash = chunk_empty;
sha512_write(this, chunk.ptr, chunk.len); if (hash)
if (hash != NULL)
{ {
sha512_final(this); *hash = allocated_hash = chunk_alloc(HASH_SIZE_SHA512);
allocated_hash = chunk_alloc(HASH_SIZE_SHA512);
memcpy(allocated_hash.ptr, this->sha_out, HASH_SIZE_SHA512);
reset512(this);
*hash = allocated_hash;
} }
return TRUE; return get_hash512(this, chunk, allocated_hash.ptr);
} }
METHOD(hasher_t, get_hash_size224, size_t, METHOD(hasher_t, get_hash_size224, size_t,