scryptjane.c

/*
	scrypt-jane by Andrew M, https://github.com/floodyberry/scrypt-jane

	Public Domain or MIT License, whichever is easier
*/

#include <string.h>

#include "scryptjane.h"
#include "scryptjane/scrypt-jane-portable.h"
#include "scryptjane/scrypt-jane-hash.h"
#include "scryptjane/scrypt-jane-romix.h"
#include "scryptjane/scrypt-jane-test-vectors.h"

#define scrypt_maxNfactor 30  /* (1 << (30 + 1)) = ~2 billion */
#if (SCRYPT_BLOCK_BYTES == 64)
#define scrypt_r_32kb 8 /* (1 << 8) = 256 * 2 blocks in a chunk * 64 bytes = Max of 32kb in a chunk */
#elif (SCRYPT_BLOCK_BYTES == 128)
#define scrypt_r_32kb 7 /* (1 << 7) = 128 * 2 blocks in a chunk * 128 bytes = Max of 32kb in a chunk */
#elif (SCRYPT_BLOCK_BYTES == 256)
#define scrypt_r_32kb 6 /* (1 << 6) = 64 * 2 blocks in a chunk * 256 bytes = Max of 32kb in a chunk */
#elif (SCRYPT_BLOCK_BYTES == 512)
#define scrypt_r_32kb 5 /* (1 << 5) = 32 * 2 blocks in a chunk * 512 bytes = Max of 32kb in a chunk */
#endif
#define scrypt_maxrfactor scrypt_r_32kb /* 32kb */
#define scrypt_maxpfactor 25  /* (1 << 25) = ~33 million */

#include <stdio.h>
//#include <malloc.h>

static void NORETURN
scrypt_fatal_error_default(const char *msg) {
    fprintf(stderr, "%s\n", msg);
    exit(1);
}

static scrypt_fatal_errorfn scrypt_fatal_error = scrypt_fatal_error_default;

void
scrypt_set_fatal_error(scrypt_fatal_errorfn fn) {
    scrypt_fatal_error = fn;
}

static int
scrypt_power_on_self_test(void) {
    const scrypt_test_setting *t;
    uint8_t test_digest[64];
    uint32_t i;
    int res = 7, scrypt_valid;

    if (!scrypt_test_mix()) {
#if !defined(SCRYPT_TEST)
        scrypt_fatal_error("scrypt: mix function power-on-self-test failed");
#endif
        res &= ~1;
    }

    if (!scrypt_test_hash()) {
#if !defined(SCRYPT_TEST)
        scrypt_fatal_error("scrypt: hash function power-on-self-test failed");
#endif
        res &= ~2;
    }

    for (i = 0, scrypt_valid = 1; post_settings[i].pw; i++) {
        t = post_settings + i;
        scrypt((uint8_t *)t->pw, strlen(t->pw), (uint8_t *)t->salt, strlen(t->salt), t->Nfactor, t->rfactor, t->pfactor, test_digest, sizeof(test_digest));
        scrypt_valid &= scrypt_verify(post_vectors[i], test_digest, sizeof(test_digest));
    }
    
    if (!scrypt_valid) {
#if !defined(SCRYPT_TEST)
        scrypt_fatal_error("scrypt: scrypt power-on-self-test failed");
#endif
        res &= ~4;
    }

    return res;
}

typedef struct scrypt_aligned_alloc_t {
    uint8_t *mem, *ptr;
} scrypt_aligned_alloc;

#if defined(SCRYPT_TEST_SPEED)
static uint8_t *mem_base = (uint8_t *)0;
static size_t mem_bump = 0;

/* allocations are assumed to be multiples of 64 bytes and total allocations not to exceed ~1.01gb */
static scrypt_aligned_alloc
scrypt_alloc(uint64_t size) {
    scrypt_aligned_alloc aa;
    if (!mem_base) {
        mem_base = (uint8_t *)malloc((1024 * 1024 * 1024) + (1024 * 1024) + (SCRYPT_BLOCK_BYTES - 1));
        if (!mem_base)
            scrypt_fatal_error("scrypt: out of memory");
        mem_base = (uint8_t *)(((size_t)mem_base + (SCRYPT_BLOCK_BYTES - 1)) & ~(SCRYPT_BLOCK_BYTES - 1));
    }
    aa.mem = mem_base + mem_bump;
    aa.ptr = aa.mem;
    mem_bump += (size_t)size;
    return aa;
}

static void
scrypt_free(scrypt_aligned_alloc *aa) {
    mem_bump = 0;
}
#else
static scrypt_aligned_alloc
scrypt_alloc(uint64_t size) {
    static const size_t max_alloc = (size_t)-1;
    scrypt_aligned_alloc aa;
    size += (SCRYPT_BLOCK_BYTES - 1);
    if (size > max_alloc)
        scrypt_fatal_error("scrypt: not enough address space on this CPU to allocate required memory");
    aa.mem = (uint8_t *)malloc((size_t)size);
    aa.ptr = (uint8_t *)(((size_t)aa.mem + (SCRYPT_BLOCK_BYTES - 1)) & ~(SCRYPT_BLOCK_BYTES - 1));
    if (!aa.mem)
        scrypt_fatal_error("scrypt: out of memory");
    return aa;
}

static void
scrypt_free(scrypt_aligned_alloc *aa) {
    free(aa->mem);
}
#endif


void
scrypt(const uint8_t *password, size_t password_len, const uint8_t *salt, size_t salt_len, uint8_t Nfactor, uint8_t rfactor, uint8_t pfactor, uint8_t *out, size_t bytes) {
    scrypt_aligned_alloc YX, V;
    uint8_t *X, *Y;
    uint32_t N, r, p, chunk_bytes, i;

#if !defined(SCRYPT_CHOOSE_COMPILETIME)
    scrypt_ROMixfn scrypt_ROMix = scrypt_getROMix();
#endif

#if !defined(SCRYPT_TEST)
    static int power_on_self_test = 0;
    if (!power_on_self_test) {
        power_on_self_test = 1;
        if (!scrypt_power_on_self_test())
            scrypt_fatal_error("scrypt: power on self test failed");
    }
#endif

    if (Nfactor > scrypt_maxNfactor)
        scrypt_fatal_error("scrypt: N out of range");
    if (rfactor > scrypt_maxrfactor)
        scrypt_fatal_error("scrypt: r out of range");
    if (pfactor > scrypt_maxpfactor)
        scrypt_fatal_error("scrypt: p out of range");

    N = (1 << (Nfactor + 1));
    r = (1 << rfactor);
    p = (1 << pfactor);

    chunk_bytes = SCRYPT_BLOCK_BYTES * r * 2;
    V = scrypt_alloc((uint64_t)N * chunk_bytes);
    YX = scrypt_alloc((p + 1) * chunk_bytes);

    /* 1: X = PBKDF2(password, salt) */
    Y = YX.ptr;
    X = Y + chunk_bytes;
    scrypt_pbkdf2(password, password_len, salt, salt_len, 1, X, chunk_bytes * p);

    /* 2: X = ROMix(X) */
    for (i = 0; i < p; i++)
        scrypt_ROMix((scrypt_mix_word_t *)(X + (chunk_bytes * i)), (scrypt_mix_word_t *)Y, (scrypt_mix_word_t *)V.ptr, N, r);

    /* 3: Out = PBKDF2(password, X) */
    scrypt_pbkdf2(password, password_len, X, chunk_bytes * p, 1, out, bytes);

    scrypt_ensure_zero(YX.ptr, (p + 1) * chunk_bytes);

    scrypt_free(&V);
    scrypt_free(&YX);
}

#define max(a,b)            (((a) > (b)) ? (a) : (b))
#define min(a,b)            (((a) < (b)) ? (a) : (b))
unsigned char GetNfactorJane(int nTimestamp, int nChainStartTime, int nMin, int nMax) {

        const unsigned char minNfactor = nMin;//4;
        const unsigned char maxNfactor = nMax;//30;

        int l = 0, s, n;
        unsigned char N;

        if (nTimestamp <= nChainStartTime)
                return 4;

        s = nTimestamp - nChainStartTime;
        while ((s >> 1) > 3) {
            l += 1;
            s >>= 1;
        }

        s &= 3;

        n = (l * 170 + s * 25 - 2320) / 100;

        if (n < 0) n = 0;

        if (n > 255)
            printf("GetNfactor(%d) - something wrong(n == %d)\n", nTimestamp, n);

        N = (unsigned char)n;
        //printf("GetNfactor: %d -> %d %d : %d / %d\n", nTimestamp - nChainStartTime, l, s, n, min(max(N, minNfactor), maxNfactor));

        return min(max(N, minNfactor), maxNfactor);
}

void scryptjane_hash(const void* input, size_t inputlen, uint32_t *res, unsigned char Nfactor)
{
    return scrypt((const unsigned char*)input, inputlen,
                  (const unsigned char*)input, inputlen,
                   Nfactor, 0, 0, (unsigned char*)res, 32);
}