sha1.c

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/** Local implementation of the SHA1 hashing scheme
 *
 * SHA-1 in C 100% Public Domain
 *
 * @file src/lib/util/sha1.c
 *
 * @author Steve Reid (steve@edmweb.com)
 */
RCSID("$Id: 0bcccca9037e19df3bb39d453cc44e9107c626dd $")
 
#include <freeradius-devel/util/sha1.h>
 
 
#ifndef WITH_OPENSSL_SHA1
#  define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
 
/* blk0() and blk() perform the initial expand. */
/* I got the idea of expanding during the round function from SSLeay */
 
#  define blk0(i) (block->l[i] = htonl(block->l[i]))
 
#  define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
    ^block->l[(i+2)&15]^block->l[i&15],1))
 
/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
#  define R0(v,w,x,y,z,i) do { z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30); } while (0)
#  define R1(v,w,x,y,z,i) do { z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30); } while (0)
#  define R2(v,w,x,y,z,i) do { z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30); } while (0)
#  define R3(v,w,x,y,z,i) do { z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30); } while (0)
#  define R4(v,w,x,y,z,i) do { z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30); } while (0)
 
 
/* Hash a single 512-bit block. This is the core of the algorithm. */
 
void fr_sha1_transform(uint32_t state[static 5], uint8_t const buffer[static 64])
{
        uint32_t a, b, c, d, e;
        typedef union {
                uint8_t c[64];
                uint32_t l[16];
        } CHAR64LONG16;
        CHAR64LONG16 *block;
        uint8_t workspace[64];
 
        block = (CHAR64LONG16*)workspace;
        memcpy(block, buffer, 64);
 
        /* Copy context->state[] to working vars */
        a = state[0];
        b = state[1];
        c = state[2];
        d = state[3];
        e = state[4];
 
        /* 4 rounds of 20 operations each. Loop unrolled. */
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
        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);
 
        /* Add the working vars back into context.state[] */
        state[0] += a;
        state[1] += b;
        state[2] += c;
        state[3] += d;
        state[4] += e;
 
#  ifndef STATIC_ANALYZER
        /* Wipe variables */
        a = b = c = d = e = 0;
#  endif
}
 
 
/* fr_sha1_init - Initialize new context */
 
void fr_sha1_init(fr_sha1_ctx* context)
{
        /* SHA1 initialization constants */
        context->state[0] = 0x67452301;
        context->state[1] = 0xEFCDAB89;
        context->state[2] = 0x98BADCFE;
        context->state[3] = 0x10325476;
        context->state[4] = 0xC3D2E1F0;
        context->count[0] = context->count[1] = 0;
}
 
/* Run your data through this. */
void fr_sha1_update(fr_sha1_ctx *context, uint8_t const *in, size_t len)
{
        unsigned int i, j;
 
        /*
         *      If len == 0, there's nothing to do:
         *      First, len == 0 impolies len * 8 == 0, so the contents of
         *      context->count wouldn't change.
         *      j by construction is <= 63, so if len == 0, j + len == j <= 63, and
         *      i would be set to 0 and the final memcpy() would "copy" 0
         *      bytes, so the contents of context->buffer wouldn't change either.
         */
        if (len == 0) return;
 
        j = (context->count[0] >> 3) & 63;
        if ((context->count[0] += len << 3) < (len << 3)) {
                context->count[1]++;
        }
 
        context->count[1] += (len >> 29);
        if ((j + len) > 63) {
                memcpy(&context->buffer[j], in, (i = 64-j));
                fr_sha1_transform(context->state, context->buffer);
                for ( ; i + 63 < len; i += 64) {
                        fr_sha1_transform(context->state, &in[i]);
                }
                j = 0;
        } else {
                i = 0;
        }
        memcpy(&context->buffer[j], &in[i], len - i);
}
 
 
/* Add padding and return the message digest. */
 
void fr_sha1_final(uint8_t digest[static SHA1_DIGEST_LENGTH], fr_sha1_ctx *context)
{
        uint32_t i, j;
        uint8_t finalcount[8];
 
        for (i = 0; i < 8; i++) {
                finalcount[i] = (uint8_t)((context->count[(i >= 4 ? 0 : 1)] >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
        }
 
        fr_sha1_update(context, (unsigned char const *) "\200", 1);
 
        while ((context->count[0] & 504) != 448) {
                fr_sha1_update(context, (unsigned char const *) "\0", 1);
        }
        fr_sha1_update(context, finalcount, 8);  /* Should cause a fr_sha1_transform() */
        for (i = 0; i < 20; i++) {
                digest[i] = (uint8_t)((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
        }
 
#  ifndef STATIC_ANALYZER
        /* Wipe variables */
        i = j = 0;
        memset(context->buffer, 0, 64);
        memset(context->state, 0, 20);
        memset(context->count, 0, 8);
        memset(&finalcount, 0, 8);
#  endif
 
#  ifdef SHA1HANDSOFF  /* make fr_sha1_transform overwrite it's own static vars */
        fr_sha1_transform(context->state, context->buffer);
#  endif
}
 
void fr_sha1_final_no_len(uint8_t digest[static SHA1_DIGEST_LENGTH], fr_sha1_ctx *context)
{
        uint32_t i, j;
 
        for (i = 0; i < 20; i++) {
                digest[i] = (uint8_t)((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
        }
 
#  ifndef STATIC_ANALYZER
        /* Wipe variables */
        i = j = 0;
        memset(context->buffer, 0, 64);
        memset(context->state, 0, 20);
        memset(context->count, 0, 8);
#  endif
 
#  ifdef SHA1HANDSOFF  /* make fr_sha1_transform overwrite it's own static vars */
        fr_sha1_transform(context->state, context->buffer);
#  endif
}
#endif