File renamed from sha.c.

Include sha1.h, not sha.h.

1 files changed, 434 insertions, 0 deletions

diff --git a/lib/sha1.c b/lib/sha1.c
new file mode 100644
index 000000000..52766bac5
--- /dev/null
+++ b/lib/sha1.c
@@ -0,0 +1,434 @@
+/* sha.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 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+/* Written by Scott G. Miller
+   Credits:
+      Robert Klep <robert@ilse.nl>  -- Expansion function fix
+*/
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "sha1.h"
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "unlocked-io.h"
+
+/*
+  Not-swap is a macro that does an endian swap on architectures that are
+  big-endian, as SHA needs some data in a little-endian format
+*/
+
+#ifdef WORDS_BIGENDIAN
+# define NOTSWAP(n) (n)
+# define SWAP(n)							\
+    (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
+#else
+# define NOTSWAP(n)                                                         \
+    (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
+# define SWAP(n) (n)
+#endif
+
+#define BLOCKSIZE 4096
+/* Ensure that BLOCKSIZE is a multiple of 64.  */
+#if BLOCKSIZE % 64 != 0
+/* FIXME-someday (soon?): use #error instead of this kludge.  */
+"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, ...  */ };
+
+
+/*
+  Takes a pointer to a 160 bit block of data (five 32 bit ints) and
+  intializes it to the start constants of the SHA1 algorithm.  This
+  must be called before using hash in the call to sha_hash
+*/
+void
+sha_init_ctx (struct sha_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 bits value.  */
+void *
+sha_read_ctx (const struct sha_ctx *ctx, void *resbuf)
+{
+  ((md5_uint32 *) resbuf)[0] = NOTSWAP (ctx->A);
+  ((md5_uint32 *) resbuf)[1] = NOTSWAP (ctx->B);
+  ((md5_uint32 *) resbuf)[2] = NOTSWAP (ctx->C);
+  ((md5_uint32 *) resbuf)[3] = NOTSWAP (ctx->D);
+  ((md5_uint32 *) resbuf)[4] = NOTSWAP (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 bits value.  */
+void *
+sha_finish_ctx (struct sha_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 + 4] = NOTSWAP (ctx->total[0] << 3);
+  *(md5_uint32 *) &ctx->buffer[bytes + pad] = NOTSWAP ((ctx->total[1] << 3) |
+						    (ctx->total[0] >> 29));
+
+  /* Process last bytes.  */
+  sha_process_block (ctx->buffer, bytes + pad + 8, ctx);
+
+  return sha_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
+sha_stream (FILE *stream, void *resblock)
+{
+  struct sha_ctx ctx;
+  char buffer[BLOCKSIZE + 72];
+  size_t sum;
+
+  /* Initialize the computation context.  */
+  sha_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
+       */
+      sha_process_block (buffer, BLOCKSIZE, &ctx);
+    }
+
+ process_partial_block:;
+
+  /* Process any remaining bytes.  */
+  if (sum > 0)
+    sha_process_bytes (buffer, sum, &ctx);
+
+  /* Construct result in desired memory.  */
+  sha_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 *
+sha_buffer (const char *buffer, size_t len, void *resblock)
+{
+  struct sha_ctx ctx;
+
+  /* Initialize the computation context.  */
+  sha_init_ctx (&ctx);
+
+  /* Process whole buffer but last len % 64 bytes.  */
+  sha_process_bytes (buffer, len, &ctx);
+
+  /* Put result in desired memory area.  */
+  return sha_finish_ctx (&ctx, resblock);
+}
+
+void
+sha_process_bytes (const void *buffer, size_t len, struct sha_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)
+	{
+	  sha_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)
+	  {
+	    sha_process_block (memcpy (ctx->buffer, buffer, 64), 64, ctx);
+	    buffer = (const char *) buffer + 64;
+	    len -= 64;
+	  }
+      else
+#endif
+	{
+	  sha_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)
+	{
+	  sha_process_block (ctx->buffer, 64, ctx);
+	  left_over -= 64;
+	  memcpy (ctx->buffer, &ctx->buffer[64], left_over);
+	}
+      ctx->buflen = left_over;
+    }
+}
+
+/* --- Code below is the primary difference between md5.c and sha.c --- */
+
+/* SHA1 round constants */
+#define K1 0x5a827999L
+#define K2 0x6ed9eba1L
+#define K3 0x8f1bbcdcL
+#define K4 0xca62c1d6L
+
+/* 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
+sha_process_block (const void *buffer, size_t len, struct sha_ctx *ctx)
+{
+  const md5_uint32 *words = buffer;
+  size_t nwords = len / sizeof (md5_uint32);
+  const md5_uint32 *endp = words + nwords;
+  md5_uint32 x[16];
+  md5_uint32 a = ctx->A;
+  md5_uint32 b = ctx->B;
+  md5_uint32 c = ctx->C;
+  md5_uint32 d = ctx->D;
+  md5_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 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)
+    {
+      md5_uint32 tm;
+      int t;
+      /* FIXME: see sha1.c for a better implementation.  */
+      for (t = 0; t < 16; t++)
+	{
+	  x[t] = NOTSWAP (*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;
+    }
+}