sha256: Use const where possible and add watchdog function

In preparation for making the hash function common, we may as well use
const where we can.

Also add a watchdog version of the hashing function.

Signed-off-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Simon Glass 2012-12-05 14:46:34 +00:00 committed by Tom Rini
parent a7d1d76579
commit ec7381fbf6
2 changed files with 42 additions and 3 deletions

View file

@ -3,6 +3,9 @@
#define SHA256_SUM_LEN 32
/* Reset watchdog each time we process this many bytes */
#define CHUNKSZ_SHA256 (64 * 1024)
typedef struct {
uint32_t total[2];
uint32_t state[8];
@ -10,7 +13,10 @@ typedef struct {
} sha256_context;
void sha256_starts(sha256_context * ctx);
void sha256_update(sha256_context * ctx, uint8_t * input, uint32_t length);
void sha256_update(sha256_context *ctx, const uint8_t *input, uint32_t length);
void sha256_finish(sha256_context * ctx, uint8_t digest[SHA256_SUM_LEN]);
void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
unsigned char *output, unsigned int chunk_sz);
#endif /* _SHA256_H */

View file

@ -60,7 +60,7 @@ void sha256_starts(sha256_context * ctx)
ctx->state[7] = 0x5BE0CD19;
}
void sha256_process(sha256_context * ctx, uint8_t data[64])
static void sha256_process(sha256_context *ctx, const uint8_t data[64])
{
uint32_t temp1, temp2;
uint32_t W[64];
@ -191,7 +191,7 @@ void sha256_process(sha256_context * ctx, uint8_t data[64])
ctx->state[7] += H;
}
void sha256_update(sha256_context * ctx, uint8_t * input, uint32_t length)
void sha256_update(sha256_context *ctx, const uint8_t *input, uint32_t length)
{
uint32_t left, fill;
@ -260,3 +260,36 @@ void sha256_finish(sha256_context * ctx, uint8_t digest[32])
PUT_UINT32_BE(ctx->state[6], digest, 24);
PUT_UINT32_BE(ctx->state[7], digest, 28);
}
/*
* Output = SHA-256( input buffer ). Trigger the watchdog every 'chunk_sz'
* bytes of input processed.
*/
void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
unsigned char *output, unsigned int chunk_sz)
{
sha256_context ctx;
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
unsigned char *end, *curr;
int chunk;
#endif
sha256_starts(&ctx);
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
curr = input;
end = input + ilen;
while (curr < end) {
chunk = end - curr;
if (chunk > chunk_sz)
chunk = chunk_sz;
sha256_update(&ctx, curr, chunk);
curr += chunk;
WATCHDOG_RESET();
}
#else
sha256_update(&ctx, input, ilen);
#endif
sha256_finish(&ctx, output);
}