-
-/* Initialize structure containing state of computation.
- (RFC 1321, 3.3: Step 3) */
-void
-md5_init_ctx (ctx)
- struct md5_ctx *ctx;
-{
- ctx->A = 0x67452301;
- ctx->B = 0xefcdab89;
- ctx->C = 0x98badcfe;
- ctx->D = 0x10325476;
-
- ctx->total[0] = ctx->total[1] = 0;
- ctx->buflen = 0;
-}
-
-/* Put result from CTX in first 16 bytes following RESBUF. The result
- must be in little endian byte order.
-
- IMPORTANT: On some systems it is required that RESBUF is correctly
- aligned for a 32 bits value. */
-void *
-md5_read_ctx (ctx, resbuf)
- const struct md5_ctx *ctx;
- void *resbuf;
-{
- ((md5_uint32 *) resbuf)[0] = SWAP (ctx->A);
- ((md5_uint32 *) resbuf)[1] = SWAP (ctx->B);
- ((md5_uint32 *) resbuf)[2] = SWAP (ctx->C);
- ((md5_uint32 *) resbuf)[3] = SWAP (ctx->D);
-
- return resbuf;
-}
-
-/* Process the remaining bytes in the internal buffer and the usual
- prolog according to the standard and write the result to RESBUF.
-
- IMPORTANT: On some systems it is required that RESBUF is correctly
- aligned for a 32 bits value. */
-void *
-md5_finish_ctx (ctx, resbuf)
- struct md5_ctx *ctx;
- void *resbuf;
-{
- /* Take yet unprocessed bytes into account. */
- md5_uint32 bytes = ctx->buflen;
- size_t pad;
-
- /* Now count remaining bytes. */
- ctx->total[0] += bytes;
- if (ctx->total[0] < bytes)
- ++ctx->total[1];
-
- pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes;
- memcpy (&ctx->buffer[bytes], fillbuf, pad);
-
- /* Put the 64-bit file length in *bits* at the end of the buffer. */
- *(md5_uint32 *) &ctx->buffer[bytes + pad] = SWAP (ctx->total[0] << 3);
- *(md5_uint32 *) &ctx->buffer[bytes + pad + 4] = SWAP ((ctx->total[1] << 3) |
- (ctx->total[0] >> 29));
-
- /* Process last bytes. */
- md5_process_block (ctx->buffer, bytes + pad + 8, ctx);
-
- return md5_read_ctx (ctx, resbuf);
-}
-
-/* Compute MD5 message digest for bytes read from STREAM. The
- resulting message digest number will be written into the 16 bytes
- beginning at RESBLOCK. */
-int
-md5_stream (stream, resblock)
- FILE *stream;
- void *resblock;
-{
- /* Important: BLOCKSIZE must be a multiple of 64. */
-#define BLOCKSIZE 4096
- struct md5_ctx ctx;
- char buffer[BLOCKSIZE + 72];
- size_t sum;
-
- /* Initialize the computation context. */
- md5_init_ctx (&ctx);
-
- /* Iterate over full file contents. */
- while (1)
- {
- /* We read the file in blocks of BLOCKSIZE bytes. One call of the
- computation function processes the whole buffer so that with the
- next round of the loop another block can be read. */
- size_t n;
- sum = 0;
-
- /* Read block. Take care for partial reads. */
- do
- {
- n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
-
- sum += n;
- }
- while (sum < BLOCKSIZE && n != 0);
- if (n == 0 && ferror (stream))
- return 1;
-
- /* If end of file is reached, end the loop. */
- if (n == 0)
- break;
-
- /* Process buffer with BLOCKSIZE bytes. Note that
- BLOCKSIZE % 64 == 0
- */
- md5_process_block (buffer, BLOCKSIZE, &ctx);
- }
-
- /* Add the last bytes if necessary. */
- if (sum > 0)
- md5_process_bytes (buffer, sum, &ctx);
-
- /* Construct result in desired memory. */
- md5_finish_ctx (&ctx, resblock);
- return 0;
-}
-
-/* Compute MD5 message digest for LEN bytes beginning at BUFFER. The
- result is always in little endian byte order, so that a byte-wise
- output yields to the wanted ASCII representation of the message
- digest. */
-void *
-md5_buffer (buffer, len, resblock)
- const char *buffer;
- size_t len;
- void *resblock;
-{
- struct md5_ctx ctx;
-
- /* Initialize the computation context. */
- md5_init_ctx (&ctx);
-
- /* Process whole buffer but last len % 64 bytes. */
- md5_process_bytes (buffer, len, &ctx);
-
- /* Put result in desired memory area. */
- return md5_finish_ctx (&ctx, resblock);
-}
-
-
-void
-md5_process_bytes (buffer, len, ctx)
- const void *buffer;
- size_t len;
- struct md5_ctx *ctx;
-{
- /* When we already have some bits in our internal buffer concatenate
- both inputs first. */
- if (ctx->buflen != 0)
- {
- size_t left_over = ctx->buflen;
- size_t add = 128 - left_over > len ? len : 128 - left_over;
-
- memcpy (&ctx->buffer[left_over], buffer, add);
- ctx->buflen += add;
-
- if (ctx->buflen > 64)
- {
- md5_process_block (ctx->buffer, ctx->buflen & ~63, ctx);
-
- ctx->buflen &= 63;
- /* The regions in the following copy operation cannot overlap. */
- memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~63],
- ctx->buflen);
- }
-
- buffer = (const char *) buffer + add;
- len -= add;
- }
-
- /* Process available complete blocks. */
- if (len >= 64)
- {
-#if !_STRING_ARCH_unaligned
-/* To check alignment gcc has an appropriate operator. Other
- compilers don't. */
-# if __GNUC__ >= 2
-# define UNALIGNED_P(p) (((md5_uintptr) p) % __alignof__ (md5_uint32) != 0)
-# else
-# define UNALIGNED_P(p) (((md5_uintptr) p) % sizeof (md5_uint32) != 0)
-# endif
- if (UNALIGNED_P (buffer))
- while (len > 64)
- {
- md5_process_block (memcpy (ctx->buffer, buffer, 64), 64, ctx);
- buffer = (const char *) buffer + 64;
- len -= 64;
- }
- else
-#endif
- {
- md5_process_block (buffer, len & ~63, ctx);
- buffer = (const char *) buffer + (len & ~63);
- len &= 63;
- }
- }
-
- /* Move remaining bytes in internal buffer. */
- if (len > 0)
- {
- size_t left_over = ctx->buflen;
-
- memcpy (&ctx->buffer[left_over], buffer, len);
- left_over += len;
- if (left_over >= 64)
- {
- md5_process_block (ctx->buffer, 64, ctx);
- left_over -= 64;
- memcpy (ctx->buffer, &ctx->buffer[64], left_over);
- }
- ctx->buflen = left_over;
- }
-}
-
-