Annotation of sys/crypto/sha1.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: sha1.c,v 1.7 2007/07/20 19:54:01 otto Exp $ */
! 2:
! 3: /*
! 4: * SHA-1 in C
! 5: * By Steve Reid <steve@edmweb.com>
! 6: * 100% Public Domain
! 7: *
! 8: * Test Vectors (from FIPS PUB 180-1)
! 9: * "abc"
! 10: * A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
! 11: * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
! 12: * 84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
! 13: * A million repetitions of "a"
! 14: * 34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
! 15: */
! 16:
! 17: /* #define LITTLE_ENDIAN * This should be #define'd already, if true. */
! 18: /* #define SHA1HANDSOFF * Copies data before messing with it. */
! 19:
! 20: #define SHA1HANDSOFF
! 21:
! 22: #include <sys/param.h>
! 23: #include <sys/systm.h>
! 24:
! 25: #include <crypto/sha1.h>
! 26:
! 27: #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
! 28:
! 29: /* blk0() and blk() perform the initial expand. */
! 30: /* I got the idea of expanding during the round function from SSLeay */
! 31: #if BYTE_ORDER == LITTLE_ENDIAN
! 32: #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
! 33: |(rol(block->l[i],8)&0x00FF00FF))
! 34: #else
! 35: #define blk0(i) block->l[i]
! 36: #endif
! 37: #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
! 38: ^block->l[(i+2)&15]^block->l[i&15],1))
! 39:
! 40: /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
! 41: #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
! 42: #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
! 43: #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
! 44: #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
! 45: #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
! 46:
! 47: /* Hash a single 512-bit block. This is the core of the algorithm. */
! 48:
! 49: void
! 50: SHA1Transform(u_int32_t state[5], unsigned char buffer[SHA1_BLOCK_LENGTH])
! 51: {
! 52: u_int32_t a, b, c, d, e;
! 53: typedef union {
! 54: unsigned char c[64];
! 55: unsigned int l[16];
! 56: } CHAR64LONG16;
! 57: CHAR64LONG16* block;
! 58: #ifdef SHA1HANDSOFF
! 59: unsigned char workspace[SHA1_BLOCK_LENGTH];
! 60:
! 61: block = (CHAR64LONG16 *)workspace;
! 62: bcopy(buffer, block, SHA1_BLOCK_LENGTH);
! 63: #else
! 64: block = (CHAR64LONG16 *)buffer;
! 65: #endif
! 66: /* Copy context->state[] to working vars */
! 67: a = state[0];
! 68: b = state[1];
! 69: c = state[2];
! 70: d = state[3];
! 71: e = state[4];
! 72:
! 73: /* 4 rounds of 20 operations each. Loop unrolled. */
! 74: 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);
! 75: 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);
! 76: 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);
! 77: 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);
! 78: 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);
! 79: 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);
! 80: 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);
! 81: 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);
! 82: 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);
! 83: 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);
! 84: 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);
! 85: 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);
! 86: 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);
! 87: 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);
! 88: 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);
! 89: 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);
! 90: 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);
! 91: 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);
! 92: 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);
! 93: 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);
! 94:
! 95: /* Add the working vars back into context.state[] */
! 96: state[0] += a;
! 97: state[1] += b;
! 98: state[2] += c;
! 99: state[3] += d;
! 100: state[4] += e;
! 101: /* Wipe variables */
! 102: a = b = c = d = e = 0;
! 103: }
! 104:
! 105:
! 106: /* SHA1Init - Initialize new context */
! 107:
! 108: void
! 109: SHA1Init(SHA1_CTX *context)
! 110: {
! 111: /* SHA1 initialization constants */
! 112: context->count = 0;
! 113: context->state[0] = 0x67452301;
! 114: context->state[1] = 0xEFCDAB89;
! 115: context->state[2] = 0x98BADCFE;
! 116: context->state[3] = 0x10325476;
! 117: context->state[4] = 0xC3D2E1F0;
! 118: }
! 119:
! 120:
! 121: /* Run your data through this. */
! 122:
! 123: void
! 124: SHA1Update(SHA1_CTX *context, unsigned char *data, unsigned int len)
! 125: {
! 126: unsigned int i;
! 127: unsigned int j;
! 128:
! 129: j = (u_int32_t)((context->count >> 3) & 63);
! 130: context->count += (len << 3);
! 131: if ((j + len) > 63) {
! 132: bcopy(data, &context->buffer[j], (i = 64 - j));
! 133: SHA1Transform(context->state, context->buffer);
! 134: for ( ; i + 63 < len; i += 64) {
! 135: SHA1Transform(context->state, &data[i]);
! 136: }
! 137: j = 0;
! 138: }
! 139: else i = 0;
! 140: bcopy(&data[i], &context->buffer[j], len - i);
! 141: }
! 142:
! 143:
! 144: /* Add padding and return the message digest. */
! 145:
! 146: void
! 147: SHA1Final(unsigned char digest[SHA1_DIGEST_LENGTH], SHA1_CTX *context)
! 148: {
! 149: unsigned int i;
! 150: unsigned char finalcount[8];
! 151:
! 152: for (i = 0; i < 8; i++) {
! 153: finalcount[i] = (unsigned char)((context->count >>
! 154: ((7 - (i & 7)) * 8)) & 255); /* Endian independent */
! 155: }
! 156: SHA1Update(context, (unsigned char *)"\200", 1);
! 157: while ((context->count & 504) != 448) {
! 158: SHA1Update(context, (unsigned char *)"\0", 1);
! 159: }
! 160: SHA1Update(context, finalcount, 8); /* Should cause a SHA1Transform() */
! 161:
! 162: if (digest)
! 163: for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {
! 164: digest[i] = (unsigned char)((context->state[i >> 2] >>
! 165: ((3 - (i & 3)) * 8)) & 255);
! 166: }
! 167: #if 0 /* We want to use this for "keyfill" */
! 168: /* Wipe variables */
! 169: i = 0;
! 170: bzero(context->buffer, 64);
! 171: bzero(context->state, 20);
! 172: bzero(context->count, 8);
! 173: bzero(&finalcount, 8);
! 174: #ifdef SHA1HANDSOFF /* make SHA1Transform overwrite its own static vars */
! 175: SHA1Transform(context->state, context->buffer);
! 176: #endif
! 177: #endif
! 178: }
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