libgit-thin: Update QUESTIONS file
[git/libgit-gsoc.git] / mozilla-sha1 / sha1.c
blob3f06b835675206912777a774d91c3ba611fa5a06
1 /*
2 * The contents of this file are subject to the Mozilla Public
3 * License Version 1.1 (the "License"); you may not use this file
4 * except in compliance with the License. You may obtain a copy of
5 * the License at http://www.mozilla.org/MPL/
7 * Software distributed under the License is distributed on an "AS
8 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
9 * implied. See the License for the specific language governing
10 * rights and limitations under the License.
12 * The Original Code is SHA 180-1 Reference Implementation (Compact version)
14 * The Initial Developer of the Original Code is Paul Kocher of
15 * Cryptography Research. Portions created by Paul Kocher are
16 * Copyright (C) 1995-9 by Cryptography Research, Inc. All
17 * Rights Reserved.
19 * Contributor(s):
21 * Paul Kocher
23 * Alternatively, the contents of this file may be used under the
24 * terms of the GNU General Public License Version 2 or later (the
25 * "GPL"), in which case the provisions of the GPL are applicable
26 * instead of those above. If you wish to allow use of your
27 * version of this file only under the terms of the GPL and not to
28 * allow others to use your version of this file under the MPL,
29 * indicate your decision by deleting the provisions above and
30 * replace them with the notice and other provisions required by
31 * the GPL. If you do not delete the provisions above, a recipient
32 * may use your version of this file under either the MPL or the
33 * GPL.
36 #include "sha1.h"
38 static void shaHashBlock(SHA_CTX *ctx);
40 void SHA1_Init(SHA_CTX *ctx) {
41 int i;
43 ctx->lenW = 0;
44 ctx->sizeHi = ctx->sizeLo = 0;
46 /* Initialize H with the magic constants (see FIPS180 for constants)
48 ctx->H[0] = 0x67452301;
49 ctx->H[1] = 0xefcdab89;
50 ctx->H[2] = 0x98badcfe;
51 ctx->H[3] = 0x10325476;
52 ctx->H[4] = 0xc3d2e1f0;
54 for (i = 0; i < 80; i++)
55 ctx->W[i] = 0;
59 void SHA1_Update(SHA_CTX *ctx, const void *_dataIn, int len) {
60 const unsigned char *dataIn = _dataIn;
61 int i;
63 /* Read the data into W and process blocks as they get full
65 for (i = 0; i < len; i++) {
66 ctx->W[ctx->lenW / 4] <<= 8;
67 ctx->W[ctx->lenW / 4] |= (unsigned int)dataIn[i];
68 if ((++ctx->lenW) % 64 == 0) {
69 shaHashBlock(ctx);
70 ctx->lenW = 0;
72 ctx->sizeLo += 8;
73 ctx->sizeHi += (ctx->sizeLo < 8);
78 void SHA1_Final(unsigned char hashout[20], SHA_CTX *ctx) {
79 unsigned char pad0x80 = 0x80;
80 unsigned char pad0x00 = 0x00;
81 unsigned char padlen[8];
82 int i;
84 /* Pad with a binary 1 (e.g. 0x80), then zeroes, then length
86 padlen[0] = (unsigned char)((ctx->sizeHi >> 24) & 255);
87 padlen[1] = (unsigned char)((ctx->sizeHi >> 16) & 255);
88 padlen[2] = (unsigned char)((ctx->sizeHi >> 8) & 255);
89 padlen[3] = (unsigned char)((ctx->sizeHi >> 0) & 255);
90 padlen[4] = (unsigned char)((ctx->sizeLo >> 24) & 255);
91 padlen[5] = (unsigned char)((ctx->sizeLo >> 16) & 255);
92 padlen[6] = (unsigned char)((ctx->sizeLo >> 8) & 255);
93 padlen[7] = (unsigned char)((ctx->sizeLo >> 0) & 255);
94 SHA1_Update(ctx, &pad0x80, 1);
95 while (ctx->lenW != 56)
96 SHA1_Update(ctx, &pad0x00, 1);
97 SHA1_Update(ctx, padlen, 8);
99 /* Output hash
101 for (i = 0; i < 20; i++) {
102 hashout[i] = (unsigned char)(ctx->H[i / 4] >> 24);
103 ctx->H[i / 4] <<= 8;
107 * Re-initialize the context (also zeroizes contents)
109 SHA1_Init(ctx);
113 #define SHA_ROT(X,n) (((X) << (n)) | ((X) >> (32-(n))))
115 static void shaHashBlock(SHA_CTX *ctx) {
116 int t;
117 unsigned int A,B,C,D,E,TEMP;
119 for (t = 16; t <= 79; t++)
120 ctx->W[t] =
121 SHA_ROT(ctx->W[t-3] ^ ctx->W[t-8] ^ ctx->W[t-14] ^ ctx->W[t-16], 1);
123 A = ctx->H[0];
124 B = ctx->H[1];
125 C = ctx->H[2];
126 D = ctx->H[3];
127 E = ctx->H[4];
129 for (t = 0; t <= 19; t++) {
130 TEMP = SHA_ROT(A,5) + (((C^D)&B)^D) + E + ctx->W[t] + 0x5a827999;
131 E = D; D = C; C = SHA_ROT(B, 30); B = A; A = TEMP;
133 for (t = 20; t <= 39; t++) {
134 TEMP = SHA_ROT(A,5) + (B^C^D) + E + ctx->W[t] + 0x6ed9eba1;
135 E = D; D = C; C = SHA_ROT(B, 30); B = A; A = TEMP;
137 for (t = 40; t <= 59; t++) {
138 TEMP = SHA_ROT(A,5) + ((B&C)|(D&(B|C))) + E + ctx->W[t] + 0x8f1bbcdc;
139 E = D; D = C; C = SHA_ROT(B, 30); B = A; A = TEMP;
141 for (t = 60; t <= 79; t++) {
142 TEMP = SHA_ROT(A,5) + (B^C^D) + E + ctx->W[t] + 0xca62c1d6;
143 E = D; D = C; C = SHA_ROT(B, 30); B = A; A = TEMP;
146 ctx->H[0] += A;
147 ctx->H[1] += B;
148 ctx->H[2] += C;
149 ctx->H[3] += D;
150 ctx->H[4] += E;