ws_utils.c

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#include "ws_utils.h"
#include <cwist/core/mem/alloc.h>
#include <stdlib.h>
#include <string.h>
 
#define ROL(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
 
/* blk0() and blk() Constants */
#if defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
#define blk0(i) (block->l[i])
#else
#define blk0(i) \
    (block->l[i] = (ROL(block->l[i], 24) & 0xFF00FF00) | (ROL(block->l[i], 8) & 0x00FF00FF))
#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);
 
typedef struct {
    uint32_t state[5];
    uint32_t count[2];
    uint8_t buffer[64];
} SHA1_CTX;
 
static void SHA1Transform(uint32_t state[5], const uint8_t *buffer) {
    uint32_t a, b, c, d, e;
    typedef union {
        uint8_t c[64];
        uint32_t l[16];
    } CHAR64LONG16;
    CHAR64LONG16 block[1]; /* use array to appear as a pointer */
 
    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 to context.state[] */
    state[0] += a;
    state[1] += b;
    state[2] += c;
    state[3] += d;
    state[4] += e;
}
 
static void SHA1Init(SHA1_CTX *context) {
    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;
}
 
static void SHA1Update(SHA1_CTX *context, const uint8_t *data, uint32_t len) {
    uint32_t i, j;
    j = context->count[0];
    if ((context->count[0] += len << 3) < j) context->count[1]++;
    context->count[1] += (len >> 29);
    j = (j >> 3) & 63;
    if ((j + len) > 63) {
        memcpy(&context->buffer[j], data, (i = 64 - j));
        /* GCC's -Wstringop-overread fires on this classic buffered-SHA1
         * shape: the block buffer is provably full here (j + 64 - j bytes),
         * and the loop below only runs while i + 63 < len. */
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstringop-overread"
        SHA1Transform(context->state, context->buffer);
        for (; i + 63 < len; i += 64) {
            SHA1Transform(context->state, &data[i]);
        }
#pragma GCC diagnostic pop
        j = 0;
    } else
        i = 0;
    memcpy(&context->buffer[j], &data[i], len - i);
}
 
static void SHA1Final(uint8_t digest[20], SHA1_CTX *context) {
    unsigned i;
    uint8_t finalcount[8];
    uint8_t c;
    for (i = 0; i < 8; i++) {
        finalcount[i] =
            (unsigned char)((context->count[(i >= 4 ? 0 : 1)] >> ((3 - (i & 3)) * 8)) & 255);
    }
    c = 0200;
    SHA1Update(context, &c, 1);
    while ((context->count[0] & 504) != 448) {
        c = 0000;
        SHA1Update(context, &c, 1);
    }
    SHA1Update(context, finalcount, 8);
    for (i = 0; i < 20; i++) {
        digest[i] = (unsigned char)((context->state[i >> 2] >> ((3 - (i & 3)) * 8)) & 255);
    }
}
 
void sha1(const uint8_t *data, size_t len, uint8_t *hash) {
    SHA1_CTX ctx;
    SHA1Init(&ctx);
    SHA1Update(&ctx, data, (uint32_t)len);
    SHA1Final(hash, &ctx);
}
 
/* --- Base64 Implementation --- */
 
static const char encoding_table[] = {
    'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
    'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
    'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
    'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'};
static const int mod_table[] = {0, 2, 1};
 
char *base64_encode(const uint8_t *data, size_t input_length, size_t *output_length) {
    *output_length = 4 * ((input_length + 2) / 3);
    char *encoded_data = (char *)cwist_alloc(*output_length + 1);
    if (encoded_data == NULL) return NULL;
 
    for (size_t i = 0, j = 0; i < input_length;) {
        uint32_t octet_a = i < input_length ? (unsigned char)data[i++] : 0;
        uint32_t octet_b = i < input_length ? (unsigned char)data[i++] : 0;
        uint32_t octet_c = i < input_length ? (unsigned char)data[i++] : 0;
 
        uint32_t triple = (octet_a << 0x10) + (octet_b << 0x08) + octet_c;
 
        encoded_data[j++] = encoding_table[(triple >> 3 * 6) & 0x3F];
        encoded_data[j++] = encoding_table[(triple >> 2 * 6) & 0x3F];
        encoded_data[j++] = encoding_table[(triple >> 1 * 6) & 0x3F];
        encoded_data[j++] = encoding_table[(triple >> 0 * 6) & 0x3F];
    }
 
    for (int i = 0; i < mod_table[input_length % 3]; i++)
        encoded_data[*output_length - 1 - i] = '=';
 
    encoded_data[*output_length] = '\0';
    return encoded_data;
}