C++ BN_get_word函數代碼示例

CHECK_RETVAL_BOOL \
static BOOLEAN selfTestGeneralOps1( void )
	{
	BIGNUM a;

	/* Simple tests that don't need the support of higher-level routines 
	   like importBignum() */
	BN_init( &a );
	if( !BN_zero( &a ) )
		return( FALSE );
	if( !BN_is_zero( &a ) || BN_is_one( &a ) )
		return( FALSE );
	if( !BN_is_word( &a, 0 ) || BN_is_word( &a, 1 ) )
		return( FALSE );
	if( BN_is_odd( &a ) )
		return( FALSE );
	if( BN_get_word( &a ) != 0 )
		return( FALSE );
	if( !BN_one( &a ) )
		return( FALSE );
	if( BN_is_zero( &a ) || !BN_is_one( &a ) )
		return( FALSE );
	if( BN_is_word( &a, 0 ) || !BN_is_word( &a, 1 ) )
		return( FALSE );
	if( !BN_is_odd( &a ) )
		return( FALSE );
	if( BN_num_bytes( &a ) != 1 )
		return( FALSE );
	if( BN_get_word( &a ) != 1 )
		return( FALSE );
	BN_clear( &a );

	return( TRUE );
	}

bool android_pubkey_encode(const RSA* key, uint8_t* key_buffer, size_t size) {
  RSAPublicKey* key_struct = (RSAPublicKey*)key_buffer;
  bool ret = false;
  BN_CTX* ctx = BN_CTX_new();
  BIGNUM* r32 = BN_new();
  BIGNUM* n0inv = BN_new();
  BIGNUM* rr = BN_new();

  if (sizeof(RSAPublicKey) > size ||
      RSA_size(key) != ANDROID_PUBKEY_MODULUS_SIZE) {
    goto cleanup;
  }

  // Store the modulus size.
  key_struct->modulus_size_words = ANDROID_PUBKEY_MODULUS_SIZE_WORDS;

  // Compute and store n0inv = -1 / N[0] mod 2^32.
  if (!ctx || !r32 || !n0inv || !BN_set_bit(r32, 32) ||
      !BN_mod(n0inv, key->n, r32, ctx) ||
      !BN_mod_inverse(n0inv, n0inv, r32, ctx) || !BN_sub(n0inv, r32, n0inv)) {
    goto cleanup;
  }
  key_struct->n0inv = (uint32_t)BN_get_word(n0inv);

  // Store the modulus.
  if (!android_pubkey_encode_bignum(key->n, key_struct->modulus)) {
    goto cleanup;
  }

  // Compute and store rr = (2^(rsa_size)) ^ 2 mod N.
  if (!ctx || !rr || !BN_set_bit(rr, ANDROID_PUBKEY_MODULUS_SIZE * 8) ||
      !BN_mod_sqr(rr, rr, key->n, ctx) ||
      !android_pubkey_encode_bignum(rr, key_struct->rr)) {
    goto cleanup;
  }

  // Store the exponent.
  key_struct->exponent = (uint32_t)BN_get_word(key->e);

  ret = true;

cleanup:
  BN_free(rr);
  BN_free(n0inv);
  BN_free(r32);
  BN_CTX_free(ctx);
  return ret;
}

static u_long
get_ulong(struct number *n)
{

	normalize(n, 0);
	return (BN_get_word(n->number));
}

static int
test_BN_import_export(void)
{
    BIGNUM *bn;
    int ret = 0;
    int i;

    bn = BN_new();

    for (i = 0; i < sizeof(ietests)/sizeof(ietests[0]); i++) {
	size_t len;
	unsigned char *p;
	if (!BN_bin2bn((unsigned char*)ietests[i].data, ietests[i].len, bn))
	    return 1;
	if (BN_get_word(bn) != ietests[i].num)
	    return 1;
	len = BN_num_bytes(bn);
	if (len != ietests[i].len)
	    return 1;
	p = malloc(len + 1);
	p[len] = 0xf4;
	BN_bn2bin(bn, p);
	if (p[len] != 0xf4)
	    return 1;
	if (memcmp(p, ietests[i].data, ietests[i].len) != 0)
	    return 1;
	free(p);
    }

    BN_free(bn);
    return ret;
}

static void
to_ascii(void)
{
	struct number *n;
	struct value *value;
	char str[2];

	value = pop();
	if (value != NULL) {
		str[1] = '\0';
		switch (value->type) {
		case BCODE_NONE:
			return;
		case BCODE_NUMBER:
			n = value->u.num;
			normalize(n, 0);
			if (BN_num_bits(n->number) > 8)
				bn_check(BN_mask_bits(n->number, 8));
			str[0] = (char)BN_get_word(n->number);
			break;
		case BCODE_STRING:
			str[0] = value->u.string[0];
			break;
		}
		stack_free_value(value);
		push_string(bstrdup(str));
	}
}

void b58encode_check(void *buf, size_t len, char *result)
{
	unsigned char hash1[32];
	unsigned char hash2[32];

	int d, p;

	BN_CTX *bnctx;
	BIGNUM *bn, *bndiv, *bntmp;
	BIGNUM bna, bnb, bnbase, bnrem;
	unsigned char *binres;
	int brlen, zpfx;

	bnctx = BN_CTX_new();
	BN_init(&bna);
	BN_init(&bnb);
	BN_init(&bnbase);
	BN_init(&bnrem);
	BN_set_word(&bnbase, 58);

	bn = &bna;
	bndiv = &bnb;

	brlen = (2 * len) + 4;
	binres = (unsigned char*) malloc(brlen);
	memcpy(binres, buf, len);

	SHA256(binres, len, hash1);
	SHA256(hash1, sizeof(hash1), hash2);
	memcpy(&binres[len], hash2, 4);

	BN_bin2bn(binres, len + 4, bn);

	for (zpfx = 0; zpfx < (len + 4) && binres[zpfx] == 0; zpfx++);

	p = brlen;
	while (!BN_is_zero(bn)) {
		BN_div(bndiv, &bnrem, bn, &bnbase, bnctx);
		bntmp = bn;
		bn = bndiv;
		bndiv = bntmp;
		d = BN_get_word(&bnrem);
		binres[--p] = b58alphabet[d];
	}

	while (zpfx--) {
		binres[--p] = b58alphabet[0];
	}

	memcpy(result, &binres[p], brlen - p);
	result[brlen - p] = '\0';

	free(binres);
	BN_clear_free(&bna);
	BN_clear_free(&bnb);
	BN_clear_free(&bnbase);
	BN_clear_free(&bnrem);
	BN_CTX_free(bnctx);
}

int rsa_plaintext_to_word(const rsa_plaintext_t *m, unsigned long *a)
{
	OPENSSL_assert(m);
	OPENSSL_assert(a);
	
	*a = BN_get_word(m);
	return 0;
}

static int fdt_add_bignum(void *blob, int noffset, const char *prop_name,
			  BIGNUM *num, int num_bits)
{
	int nwords = num_bits / 32;
	int size;
	uint32_t *buf, *ptr;
	BIGNUM *tmp, *big2, *big32, *big2_32;
	BN_CTX *ctx;
	int ret;

	tmp = BN_new();
	big2 = BN_new();
	big32 = BN_new();
	big2_32 = BN_new();
	if (!tmp || !big2 || !big32 || !big2_32) {
		fprintf(stderr, "Out of memory (bignum)\n");
		return -ENOMEM;
	}
	ctx = BN_CTX_new();
	if (!tmp) {
		fprintf(stderr, "Out of memory (bignum context)\n");
		return -ENOMEM;
	}
	BN_set_word(big2, 2L);
	BN_set_word(big32, 32L);
	BN_exp(big2_32, big2, big32, ctx); /* B = 2^32 */

	size = nwords * sizeof(uint32_t);
	buf = malloc(size);
	if (!buf) {
		fprintf(stderr, "Out of memory (%d bytes)\n", size);
		return -ENOMEM;
	}

	/* Write out modulus as big endian array of integers */
	for (ptr = buf + nwords - 1; ptr >= buf; ptr--) {
		BN_mod(tmp, num, big2_32, ctx); /* n = N mod B */
		*ptr = cpu_to_fdt32(BN_get_word(tmp));
		BN_rshift(num, num, 32); /*  N = N/B */
	}

	/*
	 * We try signing with successively increasing size values, so this
	 * might fail several times
	 */
	ret = fdt_setprop(blob, noffset, prop_name, buf, size);
	if (ret)
		return -FDT_ERR_NOSPACE;
	free(buf);
	BN_free(tmp);
	BN_free(big2);
	BN_free(big32);
	BN_free(big2_32);

	return ret;
}

/*
 * rsa_get_exponent(): - Get the public exponent from an RSA key
 */
static int rsa_get_exponent(RSA *key, uint64_t *e)
{
	int ret;
	BIGNUM *bn_te;
	uint64_t te;

	ret = -EINVAL;
	bn_te = NULL;

	if (!e)
		goto cleanup;

	if (BN_num_bits(key->e) > 64)
		goto cleanup;

	*e = BN_get_word(key->e);

	if (BN_num_bits(key->e) < 33) {
		ret = 0;
		goto cleanup;
	}

	bn_te = BN_dup(key->e);
	if (!bn_te)
		goto cleanup;

	if (!BN_rshift(bn_te, bn_te, 32))
		goto cleanup;

	if (!BN_mask_bits(bn_te, 32))
		goto cleanup;

	te = BN_get_word(bn_te);
	te <<= 32;
	*e |= te;
	ret = 0;

cleanup:
	if (bn_te)
		BN_free(bn_te);

	return ret;
}

static int fdt_add_bignum(void *blob, int noffset, const char *prop_name,
			  BIGNUM *num, int num_bits)
{
	int nwords = num_bits / 32;
	int size;
	uint32_t *buf, *ptr;
	BIGNUM *tmp, *big2, *big32, *big2_32;
	BN_CTX *ctx;
	int ret;

	tmp = BN_new();
	big2 = BN_new();
	big32 = BN_new();
	big2_32 = BN_new();
	if (!tmp || !big2 || !big32 || !big2_32) {
		fprintf(stderr, "Out of memory (bignum)\n");
		return -ENOMEM;
	}
	ctx = BN_CTX_new();
	if (!tmp) {
		fprintf(stderr, "Out of memory (bignum context)\n");
		return -ENOMEM;
	}
	BN_set_word(big2, 2L);
	BN_set_word(big32, 32L);
	BN_exp(big2_32, big2, big32, ctx); /* B = 2^32 */

	size = nwords * sizeof(uint32_t);
	buf = malloc(size);
	if (!buf) {
		fprintf(stderr, "Out of memory (%d bytes)\n", size);
		return -ENOMEM;
	}

	/* Write out modulus as big endian array of integers */
	for (ptr = buf + nwords - 1; ptr >= buf; ptr--) {
		BN_mod(tmp, num, big2_32, ctx); /* n = N mod B */
		*ptr = cpu_to_fdt32(BN_get_word(tmp));
		BN_rshift(num, num, 32); /*  N = N/B */
	}

	ret = fdt_setprop(blob, noffset, prop_name, buf, size);
	if (ret) {
		fprintf(stderr, "Failed to write public key to FIT\n");
		return -ENOSPC;
	}
	free(buf);
	BN_free(tmp);
	BN_free(big2);
	BN_free(big32);
	BN_free(big2_32);

	return ret;
}

static void
not(void)
{
	struct number *a;

	a = pop_number();
	if (a == NULL)
		return;
	a->scale = 0;
	bn_check(BN_set_word(a->number, BN_get_word(a->number) ? 0 : 1));
	push_number(a);
}

static int stackint(GPtrArray *stack, int index)
{
	struct buffer *buf = stacktop(stack, index);
	BIGNUM bn;
	BN_init(&bn);

	int ret = -1;

	if (!CastToBigNum(&bn, buf))
		goto out;

	if (!BN_is_negative(&bn))
		ret = BN_get_word(&bn);
	else {
		BN_set_negative(&bn, 0);
		ret = BN_get_word(&bn);
		ret = -ret;
	}

out:
	BN_clear_free(&bn);
	return ret;
}

int bn_probable_prime_dh_coprime(BIGNUM *rnd, int bits, BN_CTX *ctx)
{
    int i;
    BIGNUM *offset_index;
    BIGNUM *offset_count;
    int ret = 0;

    OPENSSL_assert(bits > prime_multiplier_bits);

    BN_CTX_start(ctx);
    if ((offset_index = BN_CTX_get(ctx)) == NULL)
        goto err;
    if ((offset_count = BN_CTX_get(ctx)) == NULL)
        goto err;

    if (!BN_add_word(offset_count, prime_offset_count))
        goto err;

 loop:
    if (!BN_rand(rnd, bits - prime_multiplier_bits,
                 BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ODD))
        goto err;
    if (BN_is_bit_set(rnd, bits))
        goto loop;
    if (!BN_rand_range(offset_index, offset_count))
        goto err;

    if (!BN_mul_word(rnd, prime_multiplier)
        || !BN_add_word(rnd, prime_offsets[BN_get_word(offset_index)]))
        goto err;

    /* we now have a random number 'rand' to test. */

    /* skip coprimes */
    for (i = first_prime_index; i < NUMPRIMES; i++) {
        /* check that rnd is a prime */
        BN_ULONG mod = BN_mod_word(rnd, (BN_ULONG)primes[i]);
        if (mod == (BN_ULONG)-1)
            goto err;
        if (mod <= 1)
            goto loop;
    }
    ret = 1;

 err:
    BN_CTX_end(ctx);
    bn_check_top(rnd);
    return ret;
}

static int
set_get(unsigned long num)
{
    BIGNUM *bn;

    bn = BN_new();
    if (!BN_set_word(bn, num))
	return 1;

    if (BN_get_word(bn) != num)
	return 1;

    BN_free(bn);
    return 0;
}

/*place base58 encoding of data into result*/
void base58_encode(unsigned char *data, unsigned int len, char *result) {
	const char code_string[] = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";

    BIGNUM *x, *rem, *base, *tmp, *tmp2;
    x = BN_new();
	rem = BN_new();
	base = BN_new();
	tmp = BN_new();
	char * output_string = malloc(64);

	x = BN_bin2bn(data, len, x);

	BN_set_word(rem, 1);
	BN_set_word(base, 58);

	BN_CTX *bnctx;
	bnctx = BN_CTX_new();

	int i = 0;
	while (!BN_is_zero(x)) {
		BN_div(tmp, rem, x, base, bnctx);
		output_string[i++] = code_string[BN_get_word(rem)];
		tmp2 = x;
		x = tmp;
		tmp = tmp2;
	}

	//public key
	int i2 = 0;
	while (data[i2] == 0) {
		output_string[i++] = code_string[0];
		i2++;
	}

	int base58len = i;
	while (i>=0) {
		result[base58len-i] = output_string[i-1];
		i--;
	}
	result[base58len] = 0;

	BN_free(x);
	BN_free(base);
	BN_free(rem);
	BN_free(tmp);
	BN_CTX_free(bnctx);
	free(output_string);
}