diff options
| -rw-r--r-- | md5.c | 106 |
1 files changed, 23 insertions, 83 deletions
@@ -38,110 +38,50 @@ #include "macros.h" #include "nettle-write.h" -static void -md5_final(struct md5_ctx *ctx); - void md5_init(struct md5_ctx *ctx) { - ctx->digest[0] = 0x67452301; - ctx->digest[1] = 0xefcdab89; - ctx->digest[2] = 0x98badcfe; - ctx->digest[3] = 0x10325476; - - ctx->count_l = ctx->count_h = 0; + const uint32_t iv[_MD5_DIGEST_LENGTH] = + { + 0x67452301, + 0xefcdab89, + 0x98badcfe, + 0x10325476, + }; + memcpy(ctx->state, iv, sizeof(ctx->state)); + ctx->count_low = ctx->count_high = 0; ctx->index = 0; } -#define MD5_INCR(ctx) ((ctx)->count_h += !++(ctx)->count_l) +#define COMPRESS(ctx, data) (_nettle_md5_compress((ctx)->state, (data))) void md5_update(struct md5_ctx *ctx, unsigned length, const uint8_t *data) { - if (ctx->index) - { - /* Try to fill partial block */ - unsigned left = MD5_DATA_SIZE - ctx->index; - if (length < left) - { - memcpy(ctx->block + ctx->index, data, length); - ctx->index += length; - return; /* Finished */ - } - else - { - memcpy(ctx->block + ctx->index, data, left); - - _nettle_md5_compress(ctx->digest, ctx->block); - MD5_INCR(ctx); - - data += left; - length -= left; - } - } - while (length >= MD5_DATA_SIZE) - { - _nettle_md5_compress(ctx->digest, data); - MD5_INCR(ctx); - - data += MD5_DATA_SIZE; - length -= MD5_DATA_SIZE; - } - if ((ctx->index = length)) /* This assignment is intended */ - /* Buffer leftovers */ - memcpy(ctx->block, data, length); + MD_UPDATE(ctx, length, data, COMPRESS, MD_INCR(ctx)); } void md5_digest(struct md5_ctx *ctx, unsigned length, uint8_t *digest) -{ - assert(length <= MD5_DIGEST_SIZE); - - md5_final(ctx); - _nettle_write_le32(length, digest, ctx->digest); - md5_init(ctx); -} - -/* Final wrapup - pad to MD5_DATA_SIZE-byte boundary with the bit - * pattern 1 0* (64-bit count of bits processed, LSB-first) */ - -static void -md5_final(struct md5_ctx *ctx) { - uint32_t bitcount_high; - uint32_t bitcount_low; - unsigned i; + uint32_t high, low; - i = ctx->index; + assert(length <= MD5_DIGEST_SIZE); - /* Set the first char of padding to 0x80. This is safe since there - * is always at least one byte free */ - assert(i < MD5_DATA_SIZE); - ctx->block[i++] = 0x80; + MD_PAD(ctx, 8, COMPRESS); - if (i > (MD5_DATA_SIZE - 8)) - { - /* No room for length in this block. Process it and - pad with another one */ - memset(ctx->block + i, 0, MD5_DATA_SIZE - i); - - _nettle_md5_compress(ctx->digest, ctx->block); - i = 0; - } - if (i < (MD5_DATA_SIZE - 8)) - memset(ctx->block + i, 0, (MD5_DATA_SIZE - 8) - i); - - /* There are 512 = 2^9 bits in one block - * Little-endian order => Least significant word first */ + /* There are 512 = 2^9 bits in one block */ + high = (ctx->count_high << 9) | (ctx->count_low >> 23); + low = (ctx->count_low << 9) | (ctx->index << 3); - bitcount_low = (ctx->count_l << 9) | (ctx->index << 3); - bitcount_high = (ctx->count_h << 9) | (ctx->count_l >> 23); - LE_WRITE_UINT32(ctx->block + (MD5_DATA_SIZE - 8), bitcount_low); - LE_WRITE_UINT32(ctx->block + (MD5_DATA_SIZE - 4), bitcount_high); - - _nettle_md5_compress(ctx->digest, ctx->block); + LE_WRITE_UINT32(ctx->block + (MD5_DATA_SIZE - 8), low); + LE_WRITE_UINT32(ctx->block + (MD5_DATA_SIZE - 4), high); + _nettle_md5_compress(ctx->state, ctx->block); + + _nettle_write_le32(length, digest, ctx->state); + md5_init(ctx); } |