- add checksum functions

1 files changed, 230 insertions, 0 deletions

diff --git a/src/sha1.c b/src/sha1.c
new file mode 100644
index 0000000..74262a9
--- /dev/null
+++ b/src/sha1.c
@@ -0,0 +1,230 @@
+/*
+SHA-1 in C
+By Steve Reid <sreid@sea-to-sky.net>
+100% Public Domain
+
+-----------------
+Modified 7/98
+By James H. Brown <jbrown@burgoyne.com>
+Still 100% Public Domain
+
+Corrected a problem which generated improper hash values on 16 bit machines
+Routine SHA1Update changed from
+	void SHA1Update(SHA1_CTX* context, unsigned char* data, unsigned int
+len)
+to
+	void SHA1Update(SHA1_CTX* context, unsigned char* data, unsigned
+long len)
+
+The 'len' parameter was declared an int which works fine on 32 bit machines.
+However, on 16 bit machines an int is too small for the shifts being done
+against
+it.  This caused the hash function to generate incorrect values if len was
+greater than 8191 (8K - 1) due to the 'len << 3' on line 3 of SHA1Update().
+
+Since the file IO in main() reads 16K at a time, any file 8K or larger would
+be guaranteed to generate the wrong hash (e.g. Test Vector #3, a million
+"a"s).
+
+I also changed the declaration of variables i & j in SHA1Update to
+unsigned long from unsigned int for the same reason.
+
+These changes should make no difference to any 32 bit implementations since
+an
+int and a long are the same size in those environments.
+
+--
+I also corrected a few compiler warnings generated by Borland C.
+1. Added #include <process.h> for exit() prototype
+2. Removed unused variable 'j' in SHA1Final
+3. Changed exit(0) to return(0) at end of main.
+
+ALL changes I made can be located by searching for comments containing 'JHB'
+-----------------
+Modified 8/98
+By Steve Reid <sreid@sea-to-sky.net>
+Still 100% public domain
+
+1- Removed #include <process.h> and used return() instead of exit()
+2- Fixed overwriting of finalcount in SHA1Final() (discovered by Chris Hall)
+3- Changed email address from steve@edmweb.com to sreid@sea-to-sky.net
+
+-----------------
+Modified 4/01
+By Saul Kravitz <Saul.Kravitz@celera.com>
+Still 100% PD
+Modified to run on Compaq Alpha hardware.
+
+-----------------
+Modified 07/2002
+By Ralph Giles <giles@ghostscript.com>
+Still 100% public domain
+modified for use with stdint types, autoconf
+code cleanup, removed attribution comments
+switched SHA1Final() argument order for consistency
+use SHA1_ prefix for public api
+move public api to sha1.h
+*/
+
+/*
+Test Vectors (from FIPS PUB 180-1)
+"abc"
+  A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
+"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
+  84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
+A million repetitions of "a"
+  34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
+*/
+
+#include <stdio.h>
+#include <string.h>
+#include <endian.h>
+#include "sha1.h"
+
+
+static void SHA1_Transform(uint32_t state[5], const uint8_t buffer[64]);
+
+#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
+
+/* blk0() and blk() perform the initial expand. */
+/* I got the idea of expanding during the round function from SSLeay */
+/* FIXME: can we do this in an endian-proof way? */
+#if __BYTE_ORDER == __BIG_ENDIAN
+#define blk0(i) block->l[i]
+#else
+#define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
+    |(rol(block->l[i],8)&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))
+
+/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
+#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);
+
+
+/* Hash a single 512-bit block. This is the core of the algorithm. */
+static void SHA1_Transform(uint32_t state[5], const uint8_t buffer[64])
+{
+    uint32_t a, b, c, d, e;
+    typedef union {
+        uint8_t c[64];
+        uint32_t l[16];
+    } CHAR64LONG16;
+    CHAR64LONG16* block;
+
+    block = (CHAR64LONG16*)buffer;
+
+    /* Copy context->state[] to working vars */
+    a = state[0];
+    b = state[1];
+    c = state[2];
+    d = state[3];
+    e = state[4];
+
+    /* 4 rounds of 20 operations each. Loop unrolled. */
+    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);
+
+    /* Add the working vars back into context.state[] */
+    state[0] += a;
+    state[1] += b;
+    state[2] += c;
+    state[3] += d;
+    state[4] += e;
+
+    /* Wipe variables */
+    a = b = c = d = e = 0;
+}
+
+
+/* SHA1Init - Initialize new context */
+void sat_SHA1_Init(SHA1_CTX* context)
+{
+    /* SHA1 initialization constants */
+    context->state[0] = 0x67452301;
+    context->state[1] = 0xEFCDAB89;
+    context->state[2] = 0x98BADCFE;
+    context->state[3] = 0x10325476;
+    context->state[4] = 0xC3D2E1F0;
+    context->count[0] = context->count[1] = 0;
+}
+
+
+/* Run your data through this. */
+void sat_SHA1_Update(SHA1_CTX* context, const uint8_t* data, const size_t len)
+{
+    size_t i, j;
+
+#ifdef VERBOSE
+    SHAPrintContext(context, "before");
+#endif
+
+    j = (context->count[0] >> 3) & 63;
+    if ((context->count[0] += len << 3) < (len << 3)) context->count[1]++;
+    context->count[1] += (len >> 29);
+    if ((j + len) > 63) {
+        memcpy(&context->buffer[j], data, (i = 64-j));
+        SHA1_Transform(context->state, context->buffer);
+        for ( ; i + 63 < len; i += 64) {
+            SHA1_Transform(context->state, data + i);
+        }
+        j = 0;
+    }
+    else i = 0;
+    memcpy(&context->buffer[j], &data[i], len - i);
+
+#ifdef VERBOSE
+    SHAPrintContext(context, "after ");
+#endif
+}
+
+
+/* Add padding and return the message digest. */
+void sat_SHA1_Final(SHA1_CTX* context, uint8_t digest[SHA1_DIGEST_SIZE])
+{
+    uint32_t i;
+    uint8_t  finalcount[8];
+
+    for (i = 0; i < 8; i++) {
+        finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)]
+         >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
+    }
+    sat_SHA1_Update(context, (uint8_t *)"\200", 1);
+    while ((context->count[0] & 504) != 448) {
+        sat_SHA1_Update(context, (uint8_t *)"\0", 1);
+    }
+    sat_SHA1_Update(context, finalcount, 8);  /* Should cause a SHA1_Transform() */
+    for (i = 0; i < SHA1_DIGEST_SIZE; i++) {
+        digest[i] = (uint8_t)
+         ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
+    }
+
+    /* Wipe variables */
+    i = 0;
+    memset(context->buffer, 0, 64);
+    memset(context->state, 0, 20);
+    memset(context->count, 0, 8);
+    memset(finalcount, 0, 8);	/* SWR */
+}