sha1.c
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00001 /*
00002  * modified for ldns by Jelte Jansen, original taken from OpenBSD:
00003  * 
00004  * SHA-1 in C
00005  * By Steve Reid <steve@edmweb.com>
00006  * 100% Public Domain
00007  * 
00008  * Test Vectors (from FIPS PUB 180-1)
00009  * "abc"
00010  *   A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
00011  * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
00012  *   84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
00013  * A million repetitions of "a"
00014  *   34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
00015 */
00016 
00017 /* #define LITTLE_ENDIAN * This should be #define'd already, if true. */
00018 
00019 #include <ldns/config.h>
00020 #include <ldns/ldns.h>
00021 #include <strings.h>
00022 
00023 #define SHA1HANDSOFF 1 /* Copies data before messing with it. */
00024 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
00025 
00026 /* blk0() and blk() perform the initial expand. */
00027 /* I got the idea of expanding during the round function from SSLeay */
00028 #if BYTE_ORDER == LITTLE_ENDIAN
00029 #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
00030     |(rol(block->l[i],8)&0x00FF00FF))
00031 #else
00032 #define blk0(i) block->l[i]
00033 #endif
00034 #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
00035     ^block->l[(i+2)&15]^block->l[i&15],1))
00036 
00037 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
00038 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
00039 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
00040 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
00041 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
00042 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
00043 
00044 /* Hash a single 512-bit block. This is the core of the algorithm. */
00045 
00046 void
00047 ldns_sha1_transform(uint32_t state[5], const unsigned char buffer[LDNS_SHA1_BLOCK_LENGTH])
00048 {
00049     uint32_t a, b, c, d, e;
00050     typedef union {
00051         unsigned char c[64];
00052         unsigned int l[16];
00053     } CHAR64LONG16;
00054     CHAR64LONG16* block;
00055 #ifdef SHA1HANDSOFF
00056     unsigned char workspace[LDNS_SHA1_BLOCK_LENGTH];
00057 
00058     block = (CHAR64LONG16 *)workspace;
00059     memmove(block, buffer, LDNS_SHA1_BLOCK_LENGTH);
00060 #else
00061     block = (CHAR64LONG16 *)buffer;
00062 #endif
00063     /* Copy context->state[] to working vars */
00064     a = state[0];
00065     b = state[1];
00066     c = state[2];
00067     d = state[3];
00068     e = state[4];
00069 
00070     /* 4 rounds of 20 operations each. Loop unrolled. */
00071     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);
00072     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);
00073     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);
00074     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);
00075     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);
00076     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);
00077     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);
00078     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);
00079     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);
00080     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);
00081     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);
00082     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);
00083     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);
00084     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);
00085     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);
00086     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);
00087     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);
00088     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);
00089     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);
00090     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);
00091 
00092     /* Add the working vars back into context.state[] */
00093     state[0] += a;
00094     state[1] += b;
00095     state[2] += c;
00096     state[3] += d;
00097     state[4] += e;
00098     /* Wipe variables */
00099     a = b = c = d = e = 0;
00100 }
00101 
00102 
00103 /* SHA1Init - Initialize new context */
00104 
00105 void
00106 ldns_sha1_init(ldns_sha1_ctx *context)
00107 {
00108     /* SHA1 initialization constants */
00109     context->count = 0;
00110     context->state[0] = 0x67452301;
00111     context->state[1] = 0xEFCDAB89;
00112     context->state[2] = 0x98BADCFE;
00113     context->state[3] = 0x10325476;
00114     context->state[4] = 0xC3D2E1F0;
00115 }
00116 
00117 
00118 /* Run your data through this. */
00119 
00120 void
00121 ldns_sha1_update(ldns_sha1_ctx *context, const unsigned char *data, unsigned int len)
00122 {
00123     unsigned int i;
00124     unsigned int j;
00125 
00126     j = (unsigned)(uint32_t)((context->count >> 3) & 63);
00127     context->count += (len << 3);
00128     if ((j + len) > 63) {
00129         memmove(&context->buffer[j], data, (i = 64 - j));
00130         ldns_sha1_transform(context->state, context->buffer);
00131         for ( ; i + 63 < len; i += 64) {
00132             ldns_sha1_transform(context->state, &data[i]);
00133         }
00134         j = 0;
00135     }
00136     else i = 0;
00137     memmove(&context->buffer[j], &data[i], len - i);
00138 }
00139 
00140 
00141 /* Add padding and return the message digest. */
00142 
00143 void
00144 ldns_sha1_final(unsigned char digest[LDNS_SHA1_DIGEST_LENGTH], ldns_sha1_ctx *context)
00145 {
00146     unsigned int i;
00147     unsigned char finalcount[8];
00148 
00149     for (i = 0; i < 8; i++) {
00150         finalcount[i] = (unsigned char)((context->count >>
00151             ((7 - (i & 7)) * 8)) & 255);  /* Endian independent */
00152     }
00153     ldns_sha1_update(context, (unsigned char *)"\200", 1);
00154     while ((context->count & 504) != 448) {
00155         ldns_sha1_update(context, (unsigned char *)"\0", 1);
00156     }
00157     ldns_sha1_update(context, finalcount, 8);  /* Should cause a SHA1Transform() */
00158 
00159     if (digest != NULL)
00160         for (i = 0; i < LDNS_SHA1_DIGEST_LENGTH; i++) {
00161             digest[i] = (unsigned char)((context->state[i >> 2] >>
00162                 ((3 - (i & 3)) * 8)) & 255);
00163       }
00164 #ifdef SHA1HANDSOFF  /* make SHA1Transform overwrite its own static vars */
00165     ldns_sha1_transform(context->state, context->buffer);
00166 #endif
00167 }
00168 
00169 unsigned char *
00170 ldns_sha1(unsigned char *data, unsigned int data_len, unsigned char *digest)
00171 {
00172     ldns_sha1_ctx ctx;
00173     ldns_sha1_init(&ctx);
00174     ldns_sha1_update(&ctx, data, data_len);
00175     ldns_sha1_final(digest, &ctx);
00176     return digest;
00177 }