diff options
Diffstat (limited to 'nix/libutil/sha1.c')
| -rw-r--r-- | nix/libutil/sha1.c | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/nix/libutil/sha1.c b/nix/libutil/sha1.c new file mode 100644 index 0000000000..d9d294d155 --- /dev/null +++ b/nix/libutil/sha1.c @@ -0,0 +1,369 @@ +/* $Id$ */ + +/* sha.c - Implementation of the Secure Hash Algorithm + * + * Copyright (C) 1995, A.M. Kuchling + * + * Distribute and use freely; there are no restrictions on further + * dissemination and usage except those imposed by the laws of your + * country of residence. + * + * Adapted to pike and some cleanup by Niels Möller. + */ + +/* $Id$ */ + +/* SHA: NIST's Secure Hash Algorithm */ + +/* Based on SHA code originally posted to sci.crypt by Peter Gutmann + in message <30ajo5$oe8@ccu2.auckland.ac.nz>. + Modified to test for endianness on creation of SHA objects by AMK. + Also, the original specification of SHA was found to have a weakness + by NSA/NIST. This code implements the fixed version of SHA. +*/ + +/* Here's the first paragraph of Peter Gutmann's posting: + +The following is my SHA (FIPS 180) code updated to allow use of the "fixed" +SHA, thanks to Jim Gillogly and an anonymous contributor for the information on +what's changed in the new version. The fix is a simple change which involves +adding a single rotate in the initial expansion function. It is unknown +whether this is an optimal solution to the problem which was discovered in the +SHA or whether it's simply a bandaid which fixes the problem with a minimum of +effort (for example the reengineering of a great many Capstone chips). +*/ + +#include "sha1.h" + +#include <string.h> + +void sha_copy(struct SHA_CTX *dest, struct SHA_CTX *src) +{ + unsigned int i; + + dest->count_l=src->count_l; + dest->count_h=src->count_h; + for(i=0; i<SHA_DIGESTLEN; i++) + dest->digest[i]=src->digest[i]; + for(i=0; i < src->index; i++) + dest->block[i] = src->block[i]; + dest->index = src->index; +} + + +/* The SHA f()-functions. The f1 and f3 functions can be optimized to + save one boolean operation each - thanks to Rich Schroeppel, + rcs@cs.arizona.edu for discovering this */ + +/*#define f1(x,y,z) ( ( x & y ) | ( ~x & z ) ) // Rounds 0-19 */ +#define f1(x,y,z) ( z ^ ( x & ( y ^ z ) ) ) /* Rounds 0-19 */ +#define f2(x,y,z) ( x ^ y ^ z ) /* Rounds 20-39 */ +/*#define f3(x,y,z) ( ( x & y ) | ( x & z ) | ( y & z ) ) // Rounds 40-59 */ +#define f3(x,y,z) ( ( x & y ) | ( z & ( x | y ) ) ) /* Rounds 40-59 */ +#define f4(x,y,z) ( x ^ y ^ z ) /* Rounds 60-79 */ + +/* The SHA Mysterious Constants */ + +#define K1 0x5A827999L /* Rounds 0-19 */ +#define K2 0x6ED9EBA1L /* Rounds 20-39 */ +#define K3 0x8F1BBCDCL /* Rounds 40-59 */ +#define K4 0xCA62C1D6L /* Rounds 60-79 */ + +/* SHA initial values */ + +#define h0init 0x67452301L +#define h1init 0xEFCDAB89L +#define h2init 0x98BADCFEL +#define h3init 0x10325476L +#define h4init 0xC3D2E1F0L + +/* 32-bit rotate left - kludged with shifts */ + +#define ROTL(n,X) ( ( (X) << (n) ) | ( (X) >> ( 32 - (n) ) ) ) + +/* The initial expanding function. The hash function is defined over an + 80-word expanded input array W, where the first 16 are copies of the input + data, and the remaining 64 are defined by + + W[ i ] = W[ i - 16 ] ^ W[ i - 14 ] ^ W[ i - 8 ] ^ W[ i - 3 ] + + This implementation generates these values on the fly in a circular + buffer - thanks to Colin Plumb, colin@nyx10.cs.du.edu for this + optimization. + + The updated SHA changes the expanding function by adding a rotate of 1 + bit. Thanks to Jim Gillogly, jim@rand.org, and an anonymous contributor + for this information */ + +#define expand(W,i) ( W[ i & 15 ] = \ + ROTL( 1, ( W[ i & 15 ] ^ W[ (i - 14) & 15 ] ^ \ + W[ (i - 8) & 15 ] ^ W[ (i - 3) & 15 ] ) ) ) + + +/* The prototype SHA sub-round. The fundamental sub-round is: + + a' = e + ROTL( 5, a ) + f( b, c, d ) + k + data; + b' = a; + c' = ROTL( 30, b ); + d' = c; + e' = d; + + but this is implemented by unrolling the loop 5 times and renaming the + variables ( e, a, b, c, d ) = ( a', b', c', d', e' ) each iteration. + This code is then replicated 20 times for each of the 4 functions, using + the next 20 values from the W[] array each time */ + +#define subRound(a, b, c, d, e, f, k, data) \ + ( e += ROTL( 5, a ) + f( b, c, d ) + k + data, b = ROTL( 30, b ) ) + +/* Initialize the SHA values */ + +void SHA1_Init(struct SHA_CTX *ctx) +{ + /* Set the h-vars to their initial values */ + ctx->digest[ 0 ] = h0init; + ctx->digest[ 1 ] = h1init; + ctx->digest[ 2 ] = h2init; + ctx->digest[ 3 ] = h3init; + ctx->digest[ 4 ] = h4init; + + /* Initialize bit count */ + ctx->count_l = ctx->count_h = 0; + + /* Initialize buffer */ + ctx->index = 0; +} + +/* Perform the SHA transformation. Note that this code, like MD5, seems to + break some optimizing compilers due to the complexity of the expressions + and the size of the basic block. It may be necessary to split it into + sections, e.g. based on the four subrounds + + Note that this function destroys the data area */ + +static void sha_transform(struct SHA_CTX *ctx, uint32_t *data ) +{ + uint32_t A, B, C, D, E; /* Local vars */ + + /* Set up first buffer and local data buffer */ + A = ctx->digest[0]; + B = ctx->digest[1]; + C = ctx->digest[2]; + D = ctx->digest[3]; + E = ctx->digest[4]; + + /* Heavy mangling, in 4 sub-rounds of 20 interations each. */ + subRound( A, B, C, D, E, f1, K1, data[ 0] ); + subRound( E, A, B, C, D, f1, K1, data[ 1] ); + subRound( D, E, A, B, C, f1, K1, data[ 2] ); + subRound( C, D, E, A, B, f1, K1, data[ 3] ); + subRound( B, C, D, E, A, f1, K1, data[ 4] ); + subRound( A, B, C, D, E, f1, K1, data[ 5] ); + subRound( E, A, B, C, D, f1, K1, data[ 6] ); + subRound( D, E, A, B, C, f1, K1, data[ 7] ); + subRound( C, D, E, A, B, f1, K1, data[ 8] ); + subRound( B, C, D, E, A, f1, K1, data[ 9] ); + subRound( A, B, C, D, E, f1, K1, data[10] ); + subRound( E, A, B, C, D, f1, K1, data[11] ); + subRound( D, E, A, B, C, f1, K1, data[12] ); + subRound( C, D, E, A, B, f1, K1, data[13] ); + subRound( B, C, D, E, A, f1, K1, data[14] ); + subRound( A, B, C, D, E, f1, K1, data[15] ); + subRound( E, A, B, C, D, f1, K1, expand( data, 16 ) ); + subRound( D, E, A, B, C, f1, K1, expand( data, 17 ) ); + subRound( C, D, E, A, B, f1, K1, expand( data, 18 ) ); + subRound( B, C, D, E, A, f1, K1, expand( data, 19 ) ); + + subRound( A, B, C, D, E, f2, K2, expand( data, 20 ) ); + subRound( E, A, B, C, D, f2, K2, expand( data, 21 ) ); + subRound( D, E, A, B, C, f2, K2, expand( data, 22 ) ); + subRound( C, D, E, A, B, f2, K2, expand( data, 23 ) ); + subRound( B, C, D, E, A, f2, K2, expand( data, 24 ) ); + subRound( A, B, C, D, E, f2, K2, expand( data, 25 ) ); + subRound( E, A, B, C, D, f2, K2, expand( data, 26 ) ); + subRound( D, E, A, B, C, f2, K2, expand( data, 27 ) ); + subRound( C, D, E, A, B, f2, K2, expand( data, 28 ) ); + subRound( B, C, D, E, A, f2, K2, expand( data, 29 ) ); + subRound( A, B, C, D, E, f2, K2, expand( data, 30 ) ); + subRound( E, A, B, C, D, f2, K2, expand( data, 31 ) ); + subRound( D, E, A, B, C, f2, K2, expand( data, 32 ) ); + subRound( C, D, E, A, B, f2, K2, expand( data, 33 ) ); + subRound( B, C, D, E, A, f2, K2, expand( data, 34 ) ); + subRound( A, B, C, D, E, f2, K2, expand( data, 35 ) ); + subRound( E, A, B, C, D, f2, K2, expand( data, 36 ) ); + subRound( D, E, A, B, C, f2, K2, expand( data, 37 ) ); + subRound( C, D, E, A, B, f2, K2, expand( data, 38 ) ); + subRound( B, C, D, E, A, f2, K2, expand( data, 39 ) ); + + subRound( A, B, C, D, E, f3, K3, expand( data, 40 ) ); + subRound( E, A, B, C, D, f3, K3, expand( data, 41 ) ); + subRound( D, E, A, B, C, f3, K3, expand( data, 42 ) ); + subRound( C, D, E, A, B, f3, K3, expand( data, 43 ) ); + subRound( B, C, D, E, A, f3, K3, expand( data, 44 ) ); + subRound( A, B, C, D, E, f3, K3, expand( data, 45 ) ); + subRound( E, A, B, C, D, f3, K3, expand( data, 46 ) ); + subRound( D, E, A, B, C, f3, K3, expand( data, 47 ) ); + subRound( C, D, E, A, B, f3, K3, expand( data, 48 ) ); + subRound( B, C, D, E, A, f3, K3, expand( data, 49 ) ); + subRound( A, B, C, D, E, f3, K3, expand( data, 50 ) ); + subRound( E, A, B, C, D, f3, K3, expand( data, 51 ) ); + subRound( D, E, A, B, C, f3, K3, expand( data, 52 ) ); + subRound( C, D, E, A, B, f3, K3, expand( data, 53 ) ); + subRound( B, C, D, E, A, f3, K3, expand( data, 54 ) ); + subRound( A, B, C, D, E, f3, K3, expand( data, 55 ) ); + subRound( E, A, B, C, D, f3, K3, expand( data, 56 ) ); + subRound( D, E, A, B, C, f3, K3, expand( data, 57 ) ); + subRound( C, D, E, A, B, f3, K3, expand( data, 58 ) ); + subRound( B, C, D, E, A, f3, K3, expand( data, 59 ) ); + + subRound( A, B, C, D, E, f4, K4, expand( data, 60 ) ); + subRound( E, A, B, C, D, f4, K4, expand( data, 61 ) ); + subRound( D, E, A, B, C, f4, K4, expand( data, 62 ) ); + subRound( C, D, E, A, B, f4, K4, expand( data, 63 ) ); + subRound( B, C, D, E, A, f4, K4, expand( data, 64 ) ); + subRound( A, B, C, D, E, f4, K4, expand( data, 65 ) ); + subRound( E, A, B, C, D, f4, K4, expand( data, 66 ) ); + subRound( D, E, A, B, C, f4, K4, expand( data, 67 ) ); + subRound( C, D, E, A, B, f4, K4, expand( data, 68 ) ); + subRound( B, C, D, E, A, f4, K4, expand( data, 69 ) ); + subRound( A, B, C, D, E, f4, K4, expand( data, 70 ) ); + subRound( E, A, B, C, D, f4, K4, expand( data, 71 ) ); + subRound( D, E, A, B, C, f4, K4, expand( data, 72 ) ); + subRound( C, D, E, A, B, f4, K4, expand( data, 73 ) ); + subRound( B, C, D, E, A, f4, K4, expand( data, 74 ) ); + subRound( A, B, C, D, E, f4, K4, expand( data, 75 ) ); + subRound( E, A, B, C, D, f4, K4, expand( data, 76 ) ); + subRound( D, E, A, B, C, f4, K4, expand( data, 77 ) ); + subRound( C, D, E, A, B, f4, K4, expand( data, 78 ) ); + subRound( B, C, D, E, A, f4, K4, expand( data, 79 ) ); + + /* Build message digest */ + ctx->digest[0] += A; + ctx->digest[1] += B; + ctx->digest[2] += C; + ctx->digest[3] += D; + ctx->digest[4] += E; +} + +#if 1 + +#ifndef EXTRACT_UCHAR +#define EXTRACT_UCHAR(p) (*(unsigned char *)(p)) +#endif + +#define STRING2INT(s) ((((((EXTRACT_UCHAR(s) << 8) \ + | EXTRACT_UCHAR(s+1)) << 8) \ + | EXTRACT_UCHAR(s+2)) << 8) \ + | EXTRACT_UCHAR(s+3)) +#else +uint32_t STRING2INT(unsigned char *s) +{ + uint32_t r; + unsigned int i; + + for (i = 0, r = 0; i < 4; i++, s++) + r = (r << 8) | *s; + return r; +} +#endif + +static void sha_block(struct SHA_CTX *ctx, const unsigned char *block) +{ + uint32_t data[SHA_DATALEN]; + unsigned int i; + + /* Update block count */ + if (!++ctx->count_l) + ++ctx->count_h; + + /* Endian independent conversion */ + for (i = 0; i<SHA_DATALEN; i++, block += 4) + data[i] = STRING2INT(block); + + sha_transform(ctx, data); +} + +void SHA1_Update(struct SHA_CTX *ctx, const unsigned char *buffer, uint32_t len) +{ + if (ctx->index) + { /* Try to fill partial block */ + unsigned left = SHA_DATASIZE - ctx->index; + if (len < left) + { + memcpy(ctx->block + ctx->index, buffer, len); + ctx->index += len; + return; /* Finished */ + } + else + { + memcpy(ctx->block + ctx->index, buffer, left); + sha_block(ctx, ctx->block); + buffer += left; + len -= left; + } + } + while (len >= SHA_DATASIZE) + { + sha_block(ctx, buffer); + buffer += SHA_DATASIZE; + len -= SHA_DATASIZE; + } + if ((ctx->index = len)) /* This assignment is intended */ + /* Buffer leftovers */ + memcpy(ctx->block, buffer, len); +} + +/* Final wrapup - pad to SHA_DATASIZE-byte boundary with the bit pattern + 1 0* (64-bit count of bits processed, MSB-first) */ + +void SHA1_Final(unsigned char *s, struct SHA_CTX *ctx) +{ + uint32_t data[SHA_DATALEN]; + unsigned int i; + unsigned int words; + + i = ctx->index; + /* Set the first char of padding to 0x80. This is safe since there is + always at least one byte free */ + ctx->block[i++] = 0x80; + + /* Fill rest of word */ + for( ; i & 3; i++) + ctx->block[i] = 0; + + /* i is now a multiple of the word size 4 */ + words = i >> 2; + for (i = 0; i < words; i++) + data[i] = STRING2INT(ctx->block + 4*i); + + if (words > (SHA_DATALEN-2)) + { /* No room for length in this block. Process it and + * pad with another one */ + for (i = words ; i < SHA_DATALEN; i++) + data[i] = 0; + sha_transform(ctx, data); + for (i = 0; i < (SHA_DATALEN-2); i++) + data[i] = 0; + } + else + for (i = words ; i < SHA_DATALEN - 2; i++) + data[i] = 0; + /* Theres 512 = 2^9 bits in one block */ + data[SHA_DATALEN-2] = (ctx->count_h << 9) | (ctx->count_l >> 23); + data[SHA_DATALEN-1] = (ctx->count_l << 9) | (ctx->index << 3); + sha_transform(ctx, data); + sha_digest(ctx, s); +} + +void sha_digest(struct SHA_CTX *ctx, unsigned char *s) +{ + unsigned int i; + + for (i = 0; i < SHA_DIGESTLEN; i++) + { + *s++ = ctx->digest[i] >> 24; + *s++ = 0xff & (ctx->digest[i] >> 16); + *s++ = 0xff & (ctx->digest[i] >> 8); + *s++ = 0xff & ctx->digest[i]; + } +} |