1. a project: C to Euphoria for hash algorithm
- Posted by Alan Tu <ATU5713 at COMPUSERVE.COM> Aug 05, 1998
- 512 views
There's a secure hash algorithm called SHA-1. I think it'd be interestin= g to translate the C source code to Euphoria, see how one can use the elegance of Euphoria to tackle this C monster. On top of that, we can th= en have someone or a group post it to the website for public use. Well, I don't know heads or tails of C, so I'm just putting it on the list, and s= ee what happens. Nitty-Gritty /* NIST Secure Hash Algorithm */ /* heavily modified by Uwe Hollerbach uh at alumni.caltech edu */ /* from Peter C. Gutmann's implementation as found in */ /* Applied Cryptography by Bruce Schneier */ /* NIST's proposed modification to SHA of 7/11/94 may be */ /* activated by defining USE_MODIFIED_SHA */ begin source: #include <stdlib.h> #include <stdio.h> #include <string.h> #include "sha.h" /* SHA f()-functions */ #define f1(x,y,z) ((x & y) | (~x & z)) #define f2(x,y,z) (x ^ y ^ z) #define f3(x,y,z) ((x & y) | (x & z) | (y & z)) #define f4(x,y,z) (x ^ y ^ z) /* SHA constants */ #define CONST1 0x5a827999L #define CONST2 0x6ed9eba1L #define CONST3 0x8f1bbcdcL #define CONST4 0xca62c1d6L /* 32-bit rotate */ #define ROT32(x,n) ((x << n) | (x >> (32 - n))) #define FUNC(n,i) \ temp =3D ROT32(A,5) + f##n(B,C,D) + E + W[i] + CONST##n; \ E =3D D; D =3D C; C =3D ROT32(B,30); B =3D A; A =3D temp /* do SHA transformation */ static void sha_transform(SHA_INFO *sha_info) { int i; LONG temp, A, B, C, D, E, W[80]; for (i =3D 0; i < 16; ++i) { W[i] =3D sha_info->data[i]; } for (i =3D 16; i < 80; ++i) { W[i] =3D W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16]; #ifdef USE_MODIFIED_SHA W[i] =3D ROT32(W[i], 1); #endif /* USE_MODIFIED_SHA */ } A =3D sha_info->digest[0]; B =3D sha_info->digest[1]; C =3D sha_info->digest[2]; D =3D sha_info->digest[3]; E =3D sha_info->digest[4]; #ifdef UNROLL_LOOPS FUNC(1, 0); FUNC(1, 1); FUNC(1, 2); FUNC(1, 3); FUNC(1, 4); FUNC(1, 5); FUNC(1, 6); FUNC(1, 7); FUNC(1, 8); FUNC(1, 9); FUNC(1,10); FUNC(1,11); FUNC(1,12); FUNC(1,13); FUNC(1,14); FUNC(1,15); FUNC(1,16); FUNC(1,17); FUNC(1,18); FUNC(1,19); FUNC(2,20); FUNC(2,21); FUNC(2,22); FUNC(2,23); FUNC(2,24); FUNC(2,25); FUNC(2,26); FUNC(2,27); FUNC(2,28); FUNC(2,29); FUNC(2,30); FUNC(2,31); FUNC(2,32); FUNC(2,33); FUNC(2,34); FUNC(2,35); FUNC(2,36); FUNC(2,37); FUNC(2,38); FUNC(2,39); FUNC(3,40); FUNC(3,41); FUNC(3,42); FUNC(3,43); FUNC(3,44); FUNC(3,45); FUNC(3,46); FUNC(3,47); FUNC(3,48); FUNC(3,49); FUNC(3,50); FUNC(3,51); FUNC(3,52); FUNC(3,53); FUNC(3,54); FUNC(3,55); FUNC(3,56); FUNC(3,57); FUNC(3,58); FUNC(3,59); FUNC(4,60); FUNC(4,61); FUNC(4,62); FUNC(4,63); FUNC(4,64); FUNC(4,65); FUNC(4,66); FUNC(4,67); FUNC(4,68); FUNC(4,69); FUNC(4,70); FUNC(4,71); FUNC(4,72); FUNC(4,73); FUNC(4,74); FUNC(4,75); FUNC(4,76); FUNC(4,77); FUNC(4,78); FUNC(4,79); #else /* !UNROLL_LOOPS */ for (i =3D 0; i < 20; ++i) { FUNC(1,i); } for (i =3D 20; i < 40; ++i) { FUNC(2,i); } for (i =3D 40; i < 60; ++i) { FUNC(3,i); } for (i =3D 60; i < 80; ++i) { FUNC(4,i); } #endif /* !UNROLL_LOOPS */ sha_info->digest[0] +=3D A; sha_info->digest[1] +=3D B; sha_info->digest[2] +=3D C; sha_info->digest[3] +=3D D; sha_info->digest[4] +=3D E; } #ifdef LITTLE_ENDIAN /* change endianness of data */ static void byte_reverse(LONG *buffer, int count) { int i; BYTE ct[4], *cp; count /=3D sizeof(LONG); cp =3D (BYTE *) buffer; for (i =3D 0; i < count; ++i) { ct[0] =3D cp[0]; ct[1] =3D cp[1]; ct[2] =3D cp[2]; ct[3] =3D cp[3]; cp[0] =3D ct[3]; cp[1] =3D ct[2]; cp[2] =3D ct[1]; cp[3] =3D ct[0]; cp +=3D sizeof(LONG); } } #endif /* LITTLE_ENDIAN */ /* initialize the SHA digest */ void sha_init(SHA_INFO *sha_info) { sha_info->digest[0] =3D 0x67452301L; sha_info->digest[1] =3D 0xefcdab89L; sha_info->digest[2] =3D 0x98badcfeL; sha_info->digest[3] =3D 0x10325476L; sha_info->digest[4] =3D 0xc3d2e1f0L; sha_info->count_lo =3D 0L; sha_info->count_hi =3D 0L; } /* update the SHA digest */ void sha_update(SHA_INFO *sha_info, BYTE *buffer, int count) { if ((sha_info->count_lo + ((LONG) count << 3)) < sha_info->count_lo) = { ++sha_info->count_hi; } sha_info->count_lo +=3D (LONG) count << 3; sha_info->count_hi +=3D (LONG) count >> 29; while (count >=3D SHA_BLOCKSIZE) { memcpy(sha_info->data, buffer, SHA_BLOCKSIZE); #ifdef LITTLE_ENDIAN byte_reverse(sha_info->data, SHA_BLOCKSIZE); #endif /* LITTLE_ENDIAN */ sha_transform(sha_info); buffer +=3D SHA_BLOCKSIZE; count -=3D SHA_BLOCKSIZE; } memcpy(sha_info->data, buffer, count); } /* finish computing the SHA digest */ void sha_final(SHA_INFO *sha_info) { int count; LONG lo_bit_count, hi_bit_count; lo_bit_count =3D sha_info->count_lo; hi_bit_count =3D sha_info->count_hi; count =3D (int) ((lo_bit_count >> 3) & 0x3f); ((BYTE *) sha_info->data)[count++] =3D 0x80; if (count > 56) { memset((BYTE *) &sha_info->data + count, 0, 64 - count); #ifdef LITTLE_ENDIAN byte_reverse(sha_info->data, SHA_BLOCKSIZE); #endif /* LITTLE_ENDIAN */ sha_transform(sha_info); memset(&sha_info->data, 0, 56); } else { memset((BYTE *) &sha_info->data + count, 0, 56 - count); } #ifdef LITTLE_ENDIAN byte_reverse(sha_info->data, SHA_BLOCKSIZE); #endif /* LITTLE_ENDIAN */ sha_info->data[14] =3D hi_bit_count; sha_info->data[15] =3D lo_bit_count; sha_transform(sha_info); } /* compute the SHA digest of a FILE stream */ #define BLOCK_SIZE 8192 void sha_stream(SHA_INFO *sha_info, FILE *fin) { int i; BYTE data[BLOCK_SIZE]; sha_init(sha_info); while ((i =3D fread(data, 1, BLOCK_SIZE, fin)) > 0) { sha_update(sha_info, data, i); } sha_final(sha_info); } /* print a SHA digest */ void sha_print(SHA_INFO *sha_info) { printf("%08lx %08lx %08lx %08lx %08lx\n", sha_info->digest[0], sha_info->digest[1], sha_info->digest[2], sha_info->digest[3], sha_info->digest[4]); } end source =