--- /dev/null
+/* sha1.c - Functions to compute SHA1 message digest of files or
+ memory blocks according to the NIST specification FIPS-180-1.
+
+ Copyright (C) 2000, 2001, 2003, 2004, 2005, 2006, 2008 Free Software
+ Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by the
+ Free Software Foundation; either version 2, or (at your option) any
+ later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+/* Written by Scott G. Miller
+ Credits:
+ Robert Klep <robert@ilse.nl> -- Expansion function fix
+*/
+
+#include <config.h>
+
+#include "sha1.h"
+
+#include <stddef.h>
+#include <string.h>
+
+#if USE_UNLOCKED_IO
+# include "unlocked-io.h"
+#endif
+
+#ifdef WORDS_BIGENDIAN
+# define SWAP(n) (n)
+#else
+# define SWAP(n) \
+ (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
+#endif
+
+#define BLOCKSIZE 4096
+#if BLOCKSIZE % 64 != 0
+# error "invalid BLOCKSIZE"
+#endif
+
+/* This array contains the bytes used to pad the buffer to the next
+ 64-byte boundary. (RFC 1321, 3.1: Step 1) */
+static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ... */ };
+
+
+/* Take a pointer to a 160 bit block of data (five 32 bit ints) and
+ initialize it to the start constants of the SHA1 algorithm. This
+ must be called before using hash in the call to sha1_hash. */
+void
+sha1_init_ctx (struct sha1_ctx *ctx)
+{
+ ctx->A = 0x67452301;
+ ctx->B = 0xefcdab89;
+ ctx->C = 0x98badcfe;
+ ctx->D = 0x10325476;
+ ctx->E = 0xc3d2e1f0;
+
+ ctx->total[0] = ctx->total[1] = 0;
+ ctx->buflen = 0;
+}
+
+/* Put result from CTX in first 20 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-bit value. */
+void *
+sha1_read_ctx (const struct sha1_ctx *ctx, void *resbuf)
+{
+ ((sha1_uint32 *) resbuf)[0] = SWAP (ctx->A);
+ ((sha1_uint32 *) resbuf)[1] = SWAP (ctx->B);
+ ((sha1_uint32 *) resbuf)[2] = SWAP (ctx->C);
+ ((sha1_uint32 *) resbuf)[3] = SWAP (ctx->D);
+ ((sha1_uint32 *) resbuf)[4] = SWAP (ctx->E);
+
+ 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-bit value. */
+void *
+sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf)
+{
+ /* Take yet unprocessed bytes into account. */
+ sha1_uint32 bytes = ctx->buflen;
+ size_t size = (bytes < 56) ? 64 / 4 : 64 * 2 / 4;
+
+ /* Now count remaining bytes. */
+ ctx->total[0] += bytes;
+ if (ctx->total[0] < bytes)
+ ++ctx->total[1];
+
+ /* Put the 64-bit file length in *bits* at the end of the buffer. */
+ ctx->buffer[size - 2] = SWAP ((ctx->total[1] << 3) | (ctx->total[0] >> 29));
+ ctx->buffer[size - 1] = SWAP (ctx->total[0] << 3);
+
+ memcpy (&((char *) ctx->buffer)[bytes], fillbuf, (size - 2) * 4 - bytes);
+
+ /* Process last bytes. */
+ sha1_process_block (ctx->buffer, size * 4, ctx);
+
+ return sha1_read_ctx (ctx, resbuf);
+}
+
+/* Compute SHA1 message digest for bytes read from STREAM. The
+ resulting message digest number will be written into the 16 bytes
+ beginning at RESBLOCK. */
+int
+sha1_stream (FILE *stream, void *resblock)
+{
+ struct sha1_ctx ctx;
+ char buffer[BLOCKSIZE + 72];
+ size_t sum;
+
+ /* Initialize the computation context. */
+ sha1_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. */
+ while (1)
+ {
+ n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
+
+ sum += n;
+
+ if (sum == BLOCKSIZE)
+ break;
+
+ if (n == 0)
+ {
+ /* Check for the error flag IFF N == 0, so that we don't
+ exit the loop after a partial read due to e.g., EAGAIN
+ or EWOULDBLOCK. */
+ if (ferror (stream))
+ return 1;
+ goto process_partial_block;
+ }
+
+ /* We've read at least one byte, so ignore errors. But always
+ check for EOF, since feof may be true even though N > 0.
+ Otherwise, we could end up calling fread after EOF. */
+ if (feof (stream))
+ goto process_partial_block;
+ }
+
+ /* Process buffer with BLOCKSIZE bytes. Note that
+ BLOCKSIZE % 64 == 0
+ */
+ sha1_process_block (buffer, BLOCKSIZE, &ctx);
+ }
+
+ process_partial_block:;
+
+ /* Process any remaining bytes. */
+ if (sum > 0)
+ sha1_process_bytes (buffer, sum, &ctx);
+
+ /* Construct result in desired memory. */
+ sha1_finish_ctx (&ctx, resblock);
+ return 0;
+}
+
+/* Compute SHA1 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 *
+sha1_buffer (const char *buffer, size_t len, void *resblock)
+{
+ struct sha1_ctx ctx;
+
+ /* Initialize the computation context. */
+ sha1_init_ctx (&ctx);
+
+ /* Process whole buffer but last len % 64 bytes. */
+ sha1_process_bytes (buffer, len, &ctx);
+
+ /* Put result in desired memory area. */
+ return sha1_finish_ctx (&ctx, resblock);
+}
+
+void
+sha1_process_bytes (const void *buffer, size_t len, struct sha1_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 (&((char *) ctx->buffer)[left_over], buffer, add);
+ ctx->buflen += add;
+
+ if (ctx->buflen > 64)
+ {
+ sha1_process_block (ctx->buffer, ctx->buflen & ~63, ctx);
+
+ ctx->buflen &= 63;
+ /* The regions in the following copy operation cannot overlap. */
+ memcpy (ctx->buffer,
+ &((char *) 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
+# define alignof(type) offsetof (struct { char c; type x; }, x)
+# define UNALIGNED_P(p) (((size_t) p) % alignof (sha1_uint32) != 0)
+ if (UNALIGNED_P (buffer))
+ while (len > 64)
+ {
+ sha1_process_block (memcpy (ctx->buffer, buffer, 64), 64, ctx);
+ buffer = (const char *) buffer + 64;
+ len -= 64;
+ }
+ else
+#endif
+ {
+ sha1_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 (&((char *) ctx->buffer)[left_over], buffer, len);
+ left_over += len;
+ if (left_over >= 64)
+ {
+ sha1_process_block (ctx->buffer, 64, ctx);
+ left_over -= 64;
+ memcpy (ctx->buffer, &ctx->buffer[16], left_over);
+ }
+ ctx->buflen = left_over;
+ }
+}
+
+/* --- Code below is the primary difference between md5.c and sha1.c --- */
+
+/* SHA1 round constants */
+#define K1 0x5a827999
+#define K2 0x6ed9eba1
+#define K3 0x8f1bbcdc
+#define K4 0xca62c1d6
+
+/* Round functions. Note that F2 is the same as F4. */
+#define F1(B,C,D) ( D ^ ( B & ( C ^ D ) ) )
+#define F2(B,C,D) (B ^ C ^ D)
+#define F3(B,C,D) ( ( B & C ) | ( D & ( B | C ) ) )
+#define F4(B,C,D) (B ^ C ^ D)
+
+/* Process LEN bytes of BUFFER, accumulating context into CTX.
+ It is assumed that LEN % 64 == 0.
+ Most of this code comes from GnuPG's cipher/sha1.c. */
+
+void
+sha1_process_block (const void *buffer, size_t len, struct sha1_ctx *ctx)
+{
+ const sha1_uint32 *words = (const sha1_uint32*) buffer;
+ size_t nwords = len / sizeof (sha1_uint32);
+ const sha1_uint32 *endp = words + nwords;
+ sha1_uint32 x[16];
+ sha1_uint32 a = ctx->A;
+ sha1_uint32 b = ctx->B;
+ sha1_uint32 c = ctx->C;
+ sha1_uint32 d = ctx->D;
+ sha1_uint32 e = ctx->E;
+
+ /* First increment the byte count. RFC 1321 specifies the possible
+ length of the file up to 2^64 bits. Here we only compute the
+ number of bytes. Do a double word increment. */
+ ctx->total[0] += len;
+ if (ctx->total[0] < len)
+ ++ctx->total[1];
+
+#define rol(x, n) (((x) << (n)) | ((sha1_uint32) (x) >> (32 - (n))))
+
+#define M(I) ( tm = x[I&0x0f] ^ x[(I-14)&0x0f] \
+ ^ x[(I-8)&0x0f] ^ x[(I-3)&0x0f] \
+ , (x[I&0x0f] = rol(tm, 1)) )
+
+#define R(A,B,C,D,E,F,K,M) do { E += rol( A, 5 ) \
+ + F( B, C, D ) \
+ + K \
+ + M; \
+ B = rol( B, 30 ); \
+ } while(0)
+
+ while (words < endp)
+ {
+ sha1_uint32 tm;
+ int t;
+ for (t = 0; t < 16; t++)
+ {
+ x[t] = SWAP (*words);
+ words++;
+ }
+
+ R( a, b, c, d, e, F1, K1, x[ 0] );
+ R( e, a, b, c, d, F1, K1, x[ 1] );
+ R( d, e, a, b, c, F1, K1, x[ 2] );
+ R( c, d, e, a, b, F1, K1, x[ 3] );
+ R( b, c, d, e, a, F1, K1, x[ 4] );
+ R( a, b, c, d, e, F1, K1, x[ 5] );
+ R( e, a, b, c, d, F1, K1, x[ 6] );
+ R( d, e, a, b, c, F1, K1, x[ 7] );
+ R( c, d, e, a, b, F1, K1, x[ 8] );
+ R( b, c, d, e, a, F1, K1, x[ 9] );
+ R( a, b, c, d, e, F1, K1, x[10] );
+ R( e, a, b, c, d, F1, K1, x[11] );
+ R( d, e, a, b, c, F1, K1, x[12] );
+ R( c, d, e, a, b, F1, K1, x[13] );
+ R( b, c, d, e, a, F1, K1, x[14] );
+ R( a, b, c, d, e, F1, K1, x[15] );
+ R( e, a, b, c, d, F1, K1, M(16) );
+ R( d, e, a, b, c, F1, K1, M(17) );
+ R( c, d, e, a, b, F1, K1, M(18) );
+ R( b, c, d, e, a, F1, K1, M(19) );
+ R( a, b, c, d, e, F2, K2, M(20) );
+ R( e, a, b, c, d, F2, K2, M(21) );
+ R( d, e, a, b, c, F2, K2, M(22) );
+ R( c, d, e, a, b, F2, K2, M(23) );
+ R( b, c, d, e, a, F2, K2, M(24) );
+ R( a, b, c, d, e, F2, K2, M(25) );
+ R( e, a, b, c, d, F2, K2, M(26) );
+ R( d, e, a, b, c, F2, K2, M(27) );
+ R( c, d, e, a, b, F2, K2, M(28) );
+ R( b, c, d, e, a, F2, K2, M(29) );
+ R( a, b, c, d, e, F2, K2, M(30) );
+ R( e, a, b, c, d, F2, K2, M(31) );
+ R( d, e, a, b, c, F2, K2, M(32) );
+ R( c, d, e, a, b, F2, K2, M(33) );
+ R( b, c, d, e, a, F2, K2, M(34) );
+ R( a, b, c, d, e, F2, K2, M(35) );
+ R( e, a, b, c, d, F2, K2, M(36) );
+ R( d, e, a, b, c, F2, K2, M(37) );
+ R( c, d, e, a, b, F2, K2, M(38) );
+ R( b, c, d, e, a, F2, K2, M(39) );
+ R( a, b, c, d, e, F3, K3, M(40) );
+ R( e, a, b, c, d, F3, K3, M(41) );
+ R( d, e, a, b, c, F3, K3, M(42) );
+ R( c, d, e, a, b, F3, K3, M(43) );
+ R( b, c, d, e, a, F3, K3, M(44) );
+ R( a, b, c, d, e, F3, K3, M(45) );
+ R( e, a, b, c, d, F3, K3, M(46) );
+ R( d, e, a, b, c, F3, K3, M(47) );
+ R( c, d, e, a, b, F3, K3, M(48) );
+ R( b, c, d, e, a, F3, K3, M(49) );
+ R( a, b, c, d, e, F3, K3, M(50) );
+ R( e, a, b, c, d, F3, K3, M(51) );
+ R( d, e, a, b, c, F3, K3, M(52) );
+ R( c, d, e, a, b, F3, K3, M(53) );
+ R( b, c, d, e, a, F3, K3, M(54) );
+ R( a, b, c, d, e, F3, K3, M(55) );
+ R( e, a, b, c, d, F3, K3, M(56) );
+ R( d, e, a, b, c, F3, K3, M(57) );
+ R( c, d, e, a, b, F3, K3, M(58) );
+ R( b, c, d, e, a, F3, K3, M(59) );
+ R( a, b, c, d, e, F4, K4, M(60) );
+ R( e, a, b, c, d, F4, K4, M(61) );
+ R( d, e, a, b, c, F4, K4, M(62) );
+ R( c, d, e, a, b, F4, K4, M(63) );
+ R( b, c, d, e, a, F4, K4, M(64) );
+ R( a, b, c, d, e, F4, K4, M(65) );
+ R( e, a, b, c, d, F4, K4, M(66) );
+ R( d, e, a, b, c, F4, K4, M(67) );
+ R( c, d, e, a, b, F4, K4, M(68) );
+ R( b, c, d, e, a, F4, K4, M(69) );
+ R( a, b, c, d, e, F4, K4, M(70) );
+ R( e, a, b, c, d, F4, K4, M(71) );
+ R( d, e, a, b, c, F4, K4, M(72) );
+ R( c, d, e, a, b, F4, K4, M(73) );
+ R( b, c, d, e, a, F4, K4, M(74) );
+ R( a, b, c, d, e, F4, K4, M(75) );
+ R( e, a, b, c, d, F4, K4, M(76) );
+ R( d, e, a, b, c, F4, K4, M(77) );
+ R( c, d, e, a, b, F4, K4, M(78) );
+ R( b, c, d, e, a, F4, K4, M(79) );
+
+ a = ctx->A += a;
+ b = ctx->B += b;
+ c = ctx->C += c;
+ d = ctx->D += d;
+ e = ctx->E += e;
+ }
+}
OSDN Git Service
