Add a SHA1 implementation

Add an implementation of the SHA1 hash algorithm based on a public
domain project by Steve Reid <sreid@sea-to-sky.net>. You can get the
original sources from:

    ftp://ftp.funet.fi/pub/crypt/hash/sha/sha1.c

We will need this for several things. File names of note files will be
generated based on a hash their content instead of using a random name.
Items can be uniquely identified using a hash.

In addition to the regular sha1_init(), sha1_update() and sha1_final()
operations, our implementation also contains wrappers for hashing a
string or a stream.

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

3 files changed, 300 insertions, 0 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 12147a5..942e7a2 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -8,6 +8,7 @@ calcurse_SOURCES = \
 	htable.h \
 	llist.h \
 	llist_ts.h \
+	sha1.h \
 	apoint.c \
 	args.c \
 	calendar.c \
@@ -22,6 +23,7 @@ calcurse_SOURCES = \
 	note.c \
 	notify.c \
 	recur.c \
+	sha1.c \
 	sigs.c \
 	todo.c \
 	utf8.c \
diff --git a/src/sha1.c b/src/sha1.c
new file mode 100644
index 0000000..cc11dd7
--- /dev/null
+++ b/src/sha1.c
@@ -0,0 +1,241 @@
+/*
+ * Calcurse - text-based organizer
+ *
+ * Copyright (c) 2004-2011 calcurse Development Team <misc@calcurse.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the
+ *        following disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the
+ *        following disclaimer in the documentation and/or other
+ *        materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Send your feedback or comments to : misc@calcurse.org
+ * Calcurse home page : http://calcurse.org
+ *
+ * This code is based on Steve Reid's public domain SHA1 implementation.
+ *
+ * The original version is available at:
+ *    ftp://ftp.funet.fi/pub/crypt/hash/sha/sha1.c
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include "sha1.h"
+
+#define rol(val, n) (((val) << (n)) | ((val) >> (32 - (n))))
+
+#ifdef WORDS_BIGENDIAN
+#define blk0(i) block->l[i]
+#else
+#define blk0(i) (block->l[i] = (rol (block->l[i], 24) & \
+    (uint32_t)0xFF00FF00) | (rol (block->l[i], 8) & (uint32_t)0x00FF00FF))
+#endif
+
+#define blk(i) (block->l[i & 15] = rol (block->l[(i + 13) & 15] ^ \
+    block->l[(i + 8) & 15] ^ block->l[(i + 2) & 15] ^ block->l[i & 15], 1))
+
+#define R0(v, w, x, y, z, i) z += ((w & (x ^ y)) ^ y) + blk0 (i) + \
+    0x5A827999 + rol (v, 5); w = rol (w, 30);
+#define R1(v, w, x, y, z, i) z += ((w & (x ^ y)) ^ y) + blk (i) + \
+    0x5A827999 + rol (v, 5); w = rol (w, 30);
+#define R2(v, w, x, y, z, i) z += (w ^ x ^ y) + blk (i) + 0x6ED9EBA1 + \
+    rol (v, 5); w = rol(w, 30);
+#define R3(v, w, x, y, z, i) z += (((w | x) & y) | (w & x)) + blk (i) + \
+    0x8F1BBCDC + rol (v, 5); w = rol (w, 30);
+#define R4(v, w, x, y, z, i) z += (w ^ x ^ y) + blk (i) + 0xCA62C1D6 + \
+    rol (v, 5); w = rol (w, 30);
+
+void
+sha1_transform (uint32_t state[5], const uint8_t buffer[64])
+{
+  typedef union {
+    uint8_t c[64];
+    uint32_t l[16];
+  } b64_t;
+
+  b64_t *block = (b64_t *)buffer;
+  uint32_t a = state[0];
+  uint32_t b = state[1];
+  uint32_t c = state[2];
+  uint32_t d = state[3];
+  uint32_t e = state[4];
+
+  R0 (a, b, c, d, e, 0); R0 (e, a, b, c, d, 1);
+  R0 (d, e, a, b, c, 2); R0 (c, d, e, a, b, 3);
+  R0 (b, c, d, e, a, 4); R0 (a, b, c, d, e, 5);
+  R0 (e, a, b, c, d, 6); R0 (d, e, a, b, c, 7);
+  R0 (c, d, e, a, b, 8); R0 (b, c, d, e, a, 9);
+  R0 (a, b, c, d, e, 10); R0 (e, a, b, c, d, 11);
+  R0 (d, e, a, b, c, 12); R0 (c, d, e, a, b, 13);
+  R0 (b, c, d, e, a, 14); R0 (a, b, c, d, e, 15);
+  R1 (e, a, b, c, d, 16); R1 (d, e, a, b, c, 17);
+  R1 (c, d, e, a, b, 18); R1 (b, c, d, e, a, 19);
+  R2 (a, b, c, d, e, 20); R2 (e, a, b, c, d, 21);
+  R2 (d, e, a, b, c, 22); R2 (c, d, e, a, b, 23);
+  R2 (b, c, d, e, a, 24); R2 (a, b, c, d, e, 25);
+  R2 (e, a, b, c, d, 26); R2 (d, e, a, b, c, 27);
+  R2 (c, d, e, a, b, 28); R2 (b, c, d, e, a, 29);
+  R2 (a, b, c, d, e, 30); R2 (e, a, b, c, d, 31);
+  R2 (d, e, a, b, c, 32); R2 (c, d, e, a, b, 33);
+  R2 (b, c, d, e, a, 34); R2 (a, b, c, d, e, 35);
+  R2 (e, a, b, c, d, 36); R2 (d, e, a, b, c, 37);
+  R2 (c, d, e, a, b, 38); R2 (b, c, d, e, a, 39);
+  R3 (a, b, c, d, e, 40); R3 (e, a, b, c, d, 41);
+  R3 (d, e, a, b, c, 42); R3 (c, d, e, a, b, 43);
+  R3 (b, c, d, e, a, 44); R3 (a, b, c, d, e, 45);
+  R3 (e, a, b, c, d, 46); R3 (d, e, a, b, c, 47);
+  R3 (c, d, e, a, b, 48); R3 (b, c, d, e, a, 49);
+  R3 (a, b, c, d, e, 50); R3 (e, a, b, c, d, 51);
+  R3 (d, e, a, b, c, 52); R3 (c, d, e, a, b, 53);
+  R3 (b, c, d, e, a, 54); R3 (a, b, c, d, e, 55);
+  R3 (e, a, b, c, d, 56); R3 (d, e, a, b, c, 57);
+  R3 (c, d, e, a, b, 58); R3 (b, c, d, e, a, 59);
+  R4 (a, b, c, d, e, 60); R4 (e, a, b, c, d, 61);
+  R4 (d, e, a, b, c, 62); R4 (c, d, e, a, b, 63);
+  R4 (b, c, d, e, a, 64); R4 (a, b, c, d, e, 65);
+  R4 (e, a, b, c, d, 66); R4 (d, e, a, b, c, 67);
+  R4 (c, d, e, a, b, 68); R4 (b, c, d, e, a, 69);
+  R4 (a, b, c, d, e, 70); R4 (e, a, b, c, d, 71);
+  R4 (d, e, a, b, c, 72); R4 (c, d, e, a, b, 73);
+  R4 (b, c, d, e, a, 74); R4 (a, b, c, d, e, 75);
+  R4 (e, a, b, c, d, 76); R4 (d, e, a, b, c, 77);
+  R4 (c, d, e, a, b, 78); R4 (b, c, d, e, a, 79);
+
+  state[0] += a;
+  state[1] += b;
+  state[2] += c;
+  state[3] += d;
+  state[4] += e;
+
+  a = b = c = d = e = 0;
+}
+
+
+void
+sha1_init (sha1_ctx_t *ctx)
+{
+  ctx->state[0] = 0x67452301;
+  ctx->state[1] = 0xEFCDAB89;
+  ctx->state[2] = 0x98BADCFE;
+  ctx->state[3] = 0x10325476;
+  ctx->state[4] = 0xC3D2E1F0;
+
+  ctx->count[0] = ctx->count[1] = 0;
+}
+
+void
+sha1_update (sha1_ctx_t *ctx, const uint8_t *data, unsigned int len)
+{
+  unsigned int i, j;
+
+  j = (ctx->count[0] >> 3) & 63;
+  if ((ctx->count[0] += len << 3) < (len << 3))
+    ctx->count[1]++;
+  ctx->count[1] += (len >> 29);
+
+  if (j + len > 63)
+    {
+      memcpy (&ctx->buffer[j], data, (i = 64 - j));
+      sha1_transform (ctx->state, ctx->buffer);
+      for (; i + 63 < len; i += 64)
+        sha1_transform (ctx->state, &data[i]);
+      j = 0;
+    }
+  else
+    i = 0;
+  memcpy (&ctx->buffer[j], &data[i], len - i);
+}
+
+
+void
+sha1_final (sha1_ctx_t *ctx, uint8_t digest[SHA1_DIGESTLEN])
+{
+  uint32_t i, j;
+  uint8_t  finalcount[8];
+
+  for (i = 0; i < 8; i++)
+    {
+      finalcount[i] = (uint8_t)((ctx->count[(i >= 4 ? 0 : 1)] >>
+          ((3 - (i & 3)) * 8)) & 255);
+    }
+
+  sha1_update (ctx, (uint8_t *)"\200", 1);
+  while ((ctx->count[0] & 504) != 448)
+    sha1_update (ctx, (uint8_t *)"\0", 1);
+
+  sha1_update (ctx, finalcount, 8);
+  for (i = 0; i < SHA1_DIGESTLEN; i++)
+    digest[i] = (uint8_t)((ctx->state[i >> 2] >> ((3 - (i & 3)) * 8)) & 255);
+
+  i = j = 0;
+  memset (ctx->buffer, 0, SHA1_BLOCKLEN);
+  memset (ctx->state, 0, SHA1_DIGESTLEN);
+  memset (ctx->count, 0, 8);
+  memset (&finalcount, 0, 8);
+}
+
+void
+sha1_digest (const char *data, char *buffer)
+{
+  sha1_ctx_t ctx;
+  uint8_t digest[SHA1_DIGESTLEN];
+  int i;
+
+  sha1_init (&ctx);
+  sha1_update (&ctx, (const uint8_t *)data, strlen (data));
+  sha1_final (&ctx, (uint8_t *)digest);
+
+  for (i = 0; i < SHA1_DIGESTLEN; i++)
+    {
+      snprintf (buffer, 3, "%02x", digest[i]);
+      buffer += sizeof (char) * 2;
+    }
+}
+
+void
+sha1_stream (FILE *fp, char *buffer)
+{
+  sha1_ctx_t ctx;
+  uint8_t data[BUFSIZ];
+  size_t bytes_read;
+  uint8_t digest[SHA1_DIGESTLEN];
+  int i;
+
+  sha1_init (&ctx);
+
+  while (!feof (fp))
+    {
+      bytes_read = fread (data, 1, BUFSIZ, fp);
+      sha1_update (&ctx, data, bytes_read);
+    }
+
+  sha1_final (&ctx, (uint8_t *)digest);
+
+  for (i = 0; i < SHA1_DIGESTLEN; i++)
+    {
+      snprintf (buffer, 3, "%02x", digest[i]);
+      buffer += sizeof (char) * 2;
+    }
+}
diff --git a/src/sha1.h b/src/sha1.h
new file mode 100644
index 0000000..2e28bd4
--- /dev/null
+++ b/src/sha1.h
@@ -0,0 +1,57 @@
+/*
+ * Calcurse - text-based organizer
+ *
+ * Copyright (c) 2004-2011 calcurse Development Team <misc@calcurse.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the
+ *        following disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the
+ *        following disclaimer in the documentation and/or other
+ *        materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Send your feedback or comments to : misc@calcurse.org
+ * Calcurse home page : http://calcurse.org
+ *
+ * This code is based on Steve Reid's public domain SHA1 implementation.
+ *
+ * The original version is available at:
+ *    ftp://ftp.funet.fi/pub/crypt/hash/sha/sha1.c
+ *
+ */
+
+#include <stdint.h>
+
+#define SHA1_BLOCKLEN   64
+#define SHA1_DIGESTLEN  20
+
+typedef struct {
+  uint32_t state[5];
+  uint32_t count[2];
+  uint8_t buffer[SHA1_BLOCKLEN];
+} sha1_ctx_t;
+
+void sha1_init (sha1_ctx_t *);
+void sha1_update (sha1_ctx_t *, const uint8_t *, unsigned int);
+void sha1_final (sha1_ctx_t *, uint8_t *);
+void sha1_digest (const char *, char *);
+void sha1_stream (FILE *, char *);