#include "universal.h"

#if SUPPORT_SHA1

// SHA-1 code originally from ftp://ftp.funet.fi/pub/crypt/hash/sha/sha1.c
//  License: public domain.
//  I cleaned it up a little for MojoSetup's specific purposes. --ryan.

/*
SHA-1 in C
By Steve Reid <steve@edmweb.com>
100% Public Domain

Test Vectors (from FIPS PUB 180-1)
"abc"
  A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
  84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
A million repetitions of "a"
  34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
*/

#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 */
#if PLATFORM_LITTLEENDIAN
#define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
    |(rol(block->l[i],8)&0x00FF00FF))
#else
#define blk0(i) block->l[i]
#endif
#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) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);


/* Hash a single 512-bit block. This is the core of the algorithm. */

static void MojoSha1_transform(uint32 state[5], const uint8 buffer[64])
{
    uint32 a, b, c, d, e;
    typedef union {
        uint8 c[64];
        uint32 l[16];
    } CHAR64LONG16;
    CHAR64LONG16* block;
    static uint8 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;
    /* Wipe variables */
    a = b = c = d = e = 0;
}


/* MojoSha1_init - Initialize new context */

void MojoSha1_init(MojoSha1 *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 MojoSha1_append(MojoSha1 *context, const uint8 *data, uint32 len)
{
    uint32 i, j;

    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], data, (i = 64-j));
        MojoSha1_transform(context->state, context->buffer);
        for ( ; i + 63 < len; i += 64) {
            MojoSha1_transform(context->state, &data[i]);
        }
        j = 0;
    }
    else i = 0;
    memcpy(&context->buffer[j], &data[i], len - i);
}


/* Add padding and return the message digest. */

void MojoSha1_finish(MojoSha1 *context, uint8 digest[20])
{
    uint32 i, j;
    uint8 finalcount[8];

    for (i = 0; i < 8; i++) {
        finalcount[i] = (uint8)((context->count[(i >= 4 ? 0 : 1)]
         >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
    }
    MojoSha1_append(context, (uint8 *)"\200", 1);
    while ((context->count[0] & 504) != 448) {
        MojoSha1_append(context, (uint8 *)"\0", 1);
    }
    MojoSha1_append(context, finalcount, 8);  /* Should cause a MojoSha1_transform() */
    for (i = 0; i < 20; i++) {
        digest[i] = (uint8)
         ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
    }
    /* Wipe variables */
    i = j = 0;
    memset(context->buffer, 0, 64);
    memset(context->state, 0, 20);
    memset(context->count, 0, 8);
    memset(&finalcount, 0, 8);
    MojoSha1_transform(context->state, context->buffer);
}

#endif  // SUPPORT_SHA1

#if TEST_SHA1
int main(int argc, char **argv)
{
    int i = 0;
    for (i = 1; i < argc; i++)
    {
        FILE *in = NULL;
        MojoSha1 ctx;
        MojoSha1_init(&ctx);
        in = fopen(argv[i], "rb");
        if (!in)
            perror("fopen");
        else
        {
            uint8 dig[20];
            int err = 0;
            while ( (!err) && (!feof(in)) )
            {
                uint8 buf[1024];
                size_t rc = fread(buf, 1, sizeof (buf), in);
                if (rc > 0)
                    MojoSha1_append(&ctx, buf, rc);
                err = ferror(in);
            } // while

            if (err)
                perror("fread");
            fclose(in);
            MojoSha1_finish(&ctx, dig);

            if (!err)
            {
                printf("%s: %x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x\n",
                    argv[i],
                    (int) dig[0],  (int) dig[1],  (int) dig[2],  (int) dig[3],
                    (int) dig[4],  (int) dig[5],  (int) dig[6],  (int) dig[7],
                    (int) dig[8],  (int) dig[9],  (int) dig[10], (int) dig[11],
                    (int) dig[12], (int) dig[13], (int) dig[14], (int) dig[15],
                    (int) dig[16], (int) dig[17], (int) dig[18], (int) dig[19]);
            } // if
        } // else
    } // for

    return 0;
} // main
#endif

// end of checksum_sha1.c ...