libdrizzle/sha1.c Source File

00001 
00006 /*
00007  * SHA-1 in C
00008  * By Steve Reid <steve@edmweb.com>
00009  * 100% Public Domain
00010  *
00011  * Test Vectors (from FIPS PUB 180-1)
00012  * "abc"
00013  *   A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
00014  * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
00015  *   84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
00016  * A million repetitions of "a"
00017  *   34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
00018  */
00019 
00020 #include "common.h"
00021 
00022 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
00023 
00024 /* Solaris + gcc don't always define this. */
00025 #ifndef BYTE_ORDER
00026 # define LITTLE_ENDIAN 1234
00027 # define BIG_ENDIAN 4321
00028 # if defined(sparc) || defined(__sparc) || defined(__sparc__)
00029 #  define BYTE_ORDER BIG_ENDIAN
00030 # endif
00031 #endif /* BYTE_ORDER */
00032 
00033 /*
00034  * blk0() and blk() perform the initial expand.
00035  * I got the idea of expanding during the round function from SSLeay
00036  */
00037 #if BYTE_ORDER == LITTLE_ENDIAN
00038 # define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
00039     |(rol(block->l[i],8)&0x00FF00FF))
00040 #else
00041 # define blk0(i) block->l[i]
00042 #endif
00043 #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
00044     ^block->l[(i+2)&15]^block->l[i&15],1))
00045 
00046 /*
00047  * (R0+R1), R2, R3, R4 are the different operations (rounds) used in SHA1
00048  */
00049 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
00050 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
00051 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
00052 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
00053 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
00054 
00055 /*
00056  * Hash a single 512-bit block. This is the core of the algorithm.
00057  */
00058 void
00059 SHA1Transform(uint32_t state[5], const uint8_t buffer[SHA1_BLOCK_LENGTH])
00060 {
00061         uint32_t a, b, c, d, e;
00062         uint32_t workspace_buffer[SHA1_BLOCK_LENGTH / 4];
00063         uint8_t *workspace;
00064         typedef union {
00065                 uint8_t c[64];
00066                 uint32_t l[16];
00067         } CHAR64LONG16;
00068         CHAR64LONG16 *block = (CHAR64LONG16 *)workspace_buffer;
00069         workspace= (uint8_t *)workspace_buffer;
00070 
00071         (void)memcpy(block, buffer, SHA1_BLOCK_LENGTH);
00072 
00073         /* Copy context->state[] to working vars */
00074         a = state[0];
00075         b = state[1];
00076         c = state[2];
00077         d = state[3];
00078         e = state[4];
00079 
00080         /* 4 rounds of 20 operations each. Loop unrolled. */
00081         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);
00082         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);
00083         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);
00084         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);
00085         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);
00086         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);
00087         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);
00088         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);
00089         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);
00090         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);
00091         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);
00092         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);
00093         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);
00094         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);
00095         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);
00096         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);
00097         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);
00098         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);
00099         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);
00100         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);
00101 
00102         /* Add the working vars back into context.state[] */
00103         state[0] += a;
00104         state[1] += b;
00105         state[2] += c;
00106         state[3] += d;
00107         state[4] += e;
00108 
00109         /* Wipe variables */
00110         a = b = c = d = e = 0;
00111 }
00112 
00113 
00114 /*
00115  * SHA1Init - Initialize new context
00116  */
00117 void
00118 SHA1Init(SHA1_CTX *context)
00119 {
00120 
00121         /* SHA1 initialization constants */
00122         context->count = 0;
00123         context->state[0] = 0x67452301;
00124         context->state[1] = 0xEFCDAB89;
00125         context->state[2] = 0x98BADCFE;
00126         context->state[3] = 0x10325476;
00127         context->state[4] = 0xC3D2E1F0;
00128 }
00129 
00130 
00131 /*
00132  * Run your data through this.
00133  */
00134 void
00135 SHA1Update(SHA1_CTX *context, const uint8_t *data, size_t len)
00136 {
00137         size_t i, j;
00138 
00139         j = (size_t)((context->count >> 3) & 63);
00140         context->count += (len << 3);
00141         if ((j + len) > 63) {
00142                 (void)memcpy(&context->buffer[j], data, (i = 64-j));
00143                 SHA1Transform(context->state, context->buffer);
00144                 for ( ; i + 63 < len; i += 64)
00145                         SHA1Transform(context->state, (uint8_t *)&data[i]);
00146                 j = 0;
00147         } else {
00148                 i = 0;
00149         }
00150         (void)memcpy(&context->buffer[j], &data[i], len - i);
00151 }
00152 
00153 
00154 /*
00155  * Add padding and return the message digest.
00156  */
00157 void
00158 SHA1Pad(SHA1_CTX *context)
00159 {
00160         uint8_t finalcount[8];
00161         u_int i;
00162 
00163         for (i = 0; i < 8; i++) {
00164                 finalcount[i] = (uint8_t)((context->count >>
00165                     ((7 - (i & 7)) * 8)) & 255);        /* Endian independent */
00166         }
00167         SHA1Update(context, (uint8_t *)"\200", 1);
00168         while ((context->count & 504) != 448)
00169                 SHA1Update(context, (uint8_t *)"\0", 1);
00170         SHA1Update(context, finalcount, 8); /* Should cause a SHA1Transform() */
00171 }
00172 
00173 void
00174 SHA1Final(uint8_t digest[SHA1_DIGEST_LENGTH], SHA1_CTX *context)
00175 {
00176         u_int i;
00177 
00178         SHA1Pad(context);
00179         if (digest) {
00180                 for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {
00181                         digest[i] = (uint8_t)
00182                            ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
00183                 }
00184                 memset(context, 0, sizeof(*context));
00185         }
00186 }
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libdrizzle/sha1.c
