static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in,
BIGNUM **kinvp, BIGNUM **rp,
const unsigned char *dgst, int dlen)
{
BN_CTX *ctx = NULL;
BIGNUM *k = NULL, *r = NULL, *X = NULL;
const BIGNUM *order;
EC_POINT *tmp_point = NULL;
const EC_GROUP *group;
int ret = 0;
int order_bits;
if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if (!EC_KEY_can_sign(eckey)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
return 0;
}
if (ctx_in == NULL) {
if ((ctx = BN_CTX_new()) == NULL) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE);
return 0;
}
} else
ctx = ctx_in;
k = BN_new(); /* this value is later returned in *kinvp */
r = BN_new(); /* this value is later returned in *rp */
X = BN_new();
if (k == NULL || r == NULL || X == NULL) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE);
goto err;
}
if ((tmp_point = EC_POINT_new(group)) == NULL) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
goto err;
}
order = EC_GROUP_get0_order(group);
if (order == NULL) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
goto err;
}
/* Preallocate space */
order_bits = BN_num_bits(order);
if (!BN_set_bit(k, order_bits)
|| !BN_set_bit(r, order_bits)
|| !BN_set_bit(X, order_bits))
goto err;
do {
/* get random k */
do
if (dgst != NULL) {
if (!BN_generate_dsa_nonce
(k, order, EC_KEY_get0_private_key(eckey), dgst, dlen,
ctx)) {
ECerr(EC_F_ECDSA_SIGN_SETUP,
EC_R_RANDOM_NUMBER_GENERATION_FAILED);
goto err;
}
} else {
if (!BN_priv_rand_range(k, order)) {
ECerr(EC_F_ECDSA_SIGN_SETUP,
EC_R_RANDOM_NUMBER_GENERATION_FAILED);
goto err;
}
}
while (BN_is_zero(k));
/* compute r the x-coordinate of generator * k */
if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
goto err;
}
if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) ==
NID_X9_62_prime_field) {
if (!EC_POINT_get_affine_coordinates_GFp
(group, tmp_point, X, NULL, ctx)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
goto err;
}
}
#ifndef OPENSSL_NO_EC2M
else { /* NID_X9_62_characteristic_two_field */
if (!EC_POINT_get_affine_coordinates_GF2m(group,
tmp_point, X, NULL,
ctx)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
goto err;
}
}
#endif
if (!BN_nnmod(r, X, order, ctx)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
goto err;
}
}
while (BN_is_zero(r));
/* Check if optimized inverse is implemented */
if (EC_GROUP_do_inverse_ord(group, k, k, ctx) == 0) {
/* compute the inverse of k */
if (group->mont_data != NULL) {
/*
* We want inverse in constant time, therefore we utilize the fact
* order must be prime and use Fermats Little Theorem instead.
*/
if (!BN_set_word(X, 2)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
goto err;
}
if (!BN_mod_sub(X, order, X, order, ctx)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
goto err;
}
BN_set_flags(X, BN_FLG_CONSTTIME);
if (!BN_mod_exp_mont_consttime(k, k, X, order, ctx,
group->mont_data)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
goto err;
}
} else {
if (!BN_mod_inverse(k, k, order, ctx)) {
ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
goto err;
}
}
}
/* clear old values if necessary */
BN_clear_free(*rp);
BN_clear_free(*kinvp);
/* save the pre-computed values */
*rp = r;
*kinvp = k;
ret = 1;
err:
if (!ret) {
BN_clear_free(k);
BN_clear_free(r);
}
if (ctx != ctx_in)
BN_CTX_free(ctx);
EC_POINT_free(tmp_point);
BN_clear_free(X);
return ret;
}
EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src)
{
EC_EXTRA_DATA *d;
if (dest == NULL || src == NULL)
{
ECerr(EC_F_EC_KEY_COPY, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
/* copy the parameters */
if (src->group)
{
const EC_METHOD *meth = EC_GROUP_method_of(src->group);
/* clear the old group */
if (dest->group)
EC_GROUP_free(dest->group);
dest->group = EC_GROUP_new(meth);
if (dest->group == NULL)
return NULL;
if (!EC_GROUP_copy(dest->group, src->group))
return NULL;
}
/* copy the public key */
if (src->pub_key && src->group)
{
if (dest->pub_key)
EC_POINT_free(dest->pub_key);
dest->pub_key = EC_POINT_new(src->group);
if (dest->pub_key == NULL)
return NULL;
if (!EC_POINT_copy(dest->pub_key, src->pub_key))
return NULL;
}
/* copy the private key */
if (src->priv_key)
{
if (dest->priv_key == NULL)
{
dest->priv_key = BN_new();
if (dest->priv_key == NULL)
return NULL;
}
if (!BN_copy(dest->priv_key, src->priv_key))
return NULL;
}
/* copy method/extra data */
EC_EX_DATA_free_all_data(&dest->method_data);
for (d = src->method_data; d != NULL; d = d->next)
{
void *t = d->dup_func(d->data);
if (t == NULL)
return 0;
if (!EC_EX_DATA_set_data(&dest->method_data, t, d->dup_func, d->free_func, d->clear_free_func))
return 0;
}
/* copy the rest */
dest->enc_flag = src->enc_flag;
dest->conv_form = src->conv_form;
dest->version = src->version;
dest->flags = src->flags;
return dest;
}
int EC_KEY_check_key(const EC_KEY *eckey)
{
int ok = 0;
BN_CTX *ctx = NULL;
const BIGNUM *order = NULL;
EC_POINT *point = NULL;
if (!eckey || !eckey->group || !eckey->pub_key)
{
ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key))
{
ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_AT_INFINITY);
goto err;
}
if ((ctx = BN_CTX_new()) == NULL)
goto err;
if ((point = EC_POINT_new(eckey->group)) == NULL)
goto err;
/* testing whether the pub_key is on the elliptic curve */
if (EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx) <= 0)
{
ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_IS_NOT_ON_CURVE);
goto err;
}
/* testing whether pub_key * order is the point at infinity */
order = &eckey->group->order;
if (BN_is_zero(order))
{
ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_GROUP_ORDER);
goto err;
}
if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx))
{
ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB);
goto err;
}
if (!EC_POINT_is_at_infinity(eckey->group, point))
{
ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER);
goto err;
}
/* in case the priv_key is present :
* check if generator * priv_key == pub_key
*/
if (eckey->priv_key)
{
if (BN_cmp(eckey->priv_key, order) >= 0)
{
ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER);
goto err;
}
if (!EC_POINT_mul(eckey->group, point, eckey->priv_key,
NULL, NULL, ctx))
{
ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB);
goto err;
}
if (EC_POINT_cmp(eckey->group, point, eckey->pub_key,
ctx) != 0)
{
ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_PRIVATE_KEY);
goto err;
}
}
ok = 1;
err:
if (ctx != NULL)
BN_CTX_free(ctx);
if (point != NULL)
EC_POINT_free(point);
return(ok);
}
/*
* Converts an EC_POINT to an octet string. If buf is NULL, the encoded
* length will be returned. If the length len of buf is smaller than required
* an error will be returned.
*/
size_t ec_GF2m_simple_point2oct(const EC_GROUP *group, const EC_POINT *point,
point_conversion_form_t form,
unsigned char *buf, size_t len, BN_CTX *ctx)
{
size_t ret;
BN_CTX *new_ctx = NULL;
int used_ctx = 0;
BIGNUM *x, *y, *yxi;
size_t field_len, i, skip;
if ((form != POINT_CONVERSION_COMPRESSED)
&& (form != POINT_CONVERSION_UNCOMPRESSED)
&& (form != POINT_CONVERSION_HYBRID)) {
ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_INVALID_FORM);
goto err;
}
if (EC_POINT_is_at_infinity(group, point)) {
/* encodes to a single 0 octet */
if (buf != NULL) {
if (len < 1) {
ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL);
return 0;
}
buf[0] = 0;
}
return 1;
}
/* ret := required output buffer length */
field_len = (EC_GROUP_get_degree(group) + 7) / 8;
ret =
(form ==
POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len;
/* if 'buf' is NULL, just return required length */
if (buf != NULL) {
if (len < ret) {
ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL);
goto err;
}
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
BN_CTX_start(ctx);
used_ctx = 1;
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
yxi = BN_CTX_get(ctx);
if (yxi == NULL)
goto err;
if (!EC_POINT_get_affine_coordinates_GF2m(group, point, x, y, ctx))
goto err;
buf[0] = form;
if ((form != POINT_CONVERSION_UNCOMPRESSED) && !BN_is_zero(x)) {
if (!group->meth->field_div(group, yxi, y, x, ctx))
goto err;
if (BN_is_odd(yxi))
buf[0]++;
}
i = 1;
skip = field_len - BN_num_bytes(x);
if (skip > field_len) {
ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR);
goto err;
}
while (skip > 0) {
buf[i++] = 0;
skip--;
}
skip = BN_bn2bin(x, buf + i);
i += skip;
if (i != 1 + field_len) {
ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR);
goto err;
}
if (form == POINT_CONVERSION_UNCOMPRESSED
|| form == POINT_CONVERSION_HYBRID) {
skip = field_len - BN_num_bytes(y);
if (skip > field_len) {
ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR);
goto err;
}
while (skip > 0) {
buf[i++] = 0;
skip--;
}
skip = BN_bn2bin(y, buf + i);
i += skip;
}
if (i != ret) {
ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR);
goto err;
}
}
if (used_ctx)
BN_CTX_end(ctx);
BN_CTX_free(new_ctx);
return ret;
err:
if (used_ctx)
BN_CTX_end(ctx);
BN_CTX_free(new_ctx);
return 0;
}
/*-
* Calculates and sets the affine coordinates of an EC_POINT from the given
* compressed coordinates. Uses algorithm 2.3.4 of SEC 1.
* Note that the simple implementation only uses affine coordinates.
*
* The method is from the following publication:
*
* Harper, Menezes, Vanstone:
* "Public-Key Cryptosystems with Very Small Key Lengths",
* EUROCRYPT '92, Springer-Verlag LNCS 658,
* published February 1993
*
* US Patents 6,141,420 and 6,618,483 (Vanstone, Mullin, Agnew) describe
* the same method, but claim no priority date earlier than July 29, 1994
* (and additionally fail to cite the EUROCRYPT '92 publication as prior art).
*/
int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *group,
EC_POINT *point,
const BIGNUM *x_, int y_bit,
BN_CTX *ctx)
{
BN_CTX *new_ctx = NULL;
BIGNUM *tmp, *x, *y, *z;
int ret = 0, z0;
/* clear error queue */
ERR_clear_error();
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
y_bit = (y_bit != 0) ? 1 : 0;
BN_CTX_start(ctx);
tmp = BN_CTX_get(ctx);
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
z = BN_CTX_get(ctx);
if (z == NULL)
goto err;
if (!BN_GF2m_mod_arr(x, x_, group->poly))
goto err;
if (BN_is_zero(x)) {
if (!BN_GF2m_mod_sqrt_arr(y, group->b, group->poly, ctx))
goto err;
} else {
if (!group->meth->field_sqr(group, tmp, x, ctx))
goto err;
if (!group->meth->field_div(group, tmp, group->b, tmp, ctx))
goto err;
if (!BN_GF2m_add(tmp, group->a, tmp))
goto err;
if (!BN_GF2m_add(tmp, x, tmp))
goto err;
if (!BN_GF2m_mod_solve_quad_arr(z, tmp, group->poly, ctx)) {
unsigned long err = ERR_peek_last_error();
if (ERR_GET_LIB(err) == ERR_LIB_BN
&& ERR_GET_REASON(err) == BN_R_NO_SOLUTION) {
ERR_clear_error();
ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES,
EC_R_INVALID_COMPRESSED_POINT);
} else
ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES,
ERR_R_BN_LIB);
goto err;
}
z0 = (BN_is_odd(z)) ? 1 : 0;
if (!group->meth->field_mul(group, y, x, z, ctx))
goto err;
if (z0 != y_bit) {
if (!BN_GF2m_add(y, y, x))
goto err;
}
}
if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx))
goto err;
ret = 1;
err:
BN_CTX_end(ctx);
BN_CTX_free(new_ctx);
return ret;
}
int ECPKParameters_print(BIO *bp, const EC_GROUP *x, int off)
{
unsigned char *buffer=NULL;
size_t buf_len=0, i;
int ret=0, reason=ERR_R_BIO_LIB;
BN_CTX *ctx=NULL;
const EC_POINT *point=NULL;
BIGNUM *p=NULL, *a=NULL, *b=NULL, *gen=NULL,
*order=NULL, *cofactor=NULL;
const unsigned char *seed;
size_t seed_len=0;
static const char *gen_compressed = "Generator (compressed):";
static const char *gen_uncompressed = "Generator (uncompressed):";
static const char *gen_hybrid = "Generator (hybrid):";
if (!x)
{
reason = ERR_R_PASSED_NULL_PARAMETER;
goto err;
}
if (EC_GROUP_get_asn1_flag(x))
{
/* the curve parameter are given by an asn1 OID */
int nid;
if (!BIO_indent(bp, off, 128))
goto err;
nid = EC_GROUP_get_curve_name(x);
if (nid == 0)
goto err;
if (BIO_printf(bp, "ASN1 OID: %s", OBJ_nid2sn(nid)) <= 0)
goto err;
if (BIO_printf(bp, "\n") <= 0)
goto err;
}
else
{
/* explicit parameters */
int is_char_two = 0;
point_conversion_form_t form;
int tmp_nid = EC_METHOD_get_field_type(EC_GROUP_method_of(x));
if (tmp_nid == NID_X9_62_characteristic_two_field)
is_char_two = 1;
if ((p = BN_new()) == NULL || (a = BN_new()) == NULL ||
(b = BN_new()) == NULL || (order = BN_new()) == NULL ||
(cofactor = BN_new()) == NULL)
{
reason = ERR_R_MALLOC_FAILURE;
goto err;
}
if (is_char_two)
{
if (!EC_GROUP_get_curve_GF2m(x, p, a, b, ctx))
{
reason = ERR_R_EC_LIB;
goto err;
}
}
else /* prime field */
{
if (!EC_GROUP_get_curve_GFp(x, p, a, b, ctx))
{
reason = ERR_R_EC_LIB;
goto err;
}
}
if ((point = EC_GROUP_get0_generator(x)) == NULL)
{
reason = ERR_R_EC_LIB;
goto err;
}
if (!EC_GROUP_get_order(x, order, NULL) ||
!EC_GROUP_get_cofactor(x, cofactor, NULL))
{
reason = ERR_R_EC_LIB;
goto err;
}
form = EC_GROUP_get_point_conversion_form(x);
if ((gen = EC_POINT_point2bn(x, point,
form, NULL, ctx)) == NULL)
{
reason = ERR_R_EC_LIB;
goto err;
}
buf_len = (size_t)BN_num_bytes(p);
if (buf_len < (i = (size_t)BN_num_bytes(a)))
buf_len = i;
if (buf_len < (i = (size_t)BN_num_bytes(b)))
buf_len = i;
if (buf_len < (i = (size_t)BN_num_bytes(gen)))
buf_len = i;
if (buf_len < (i = (size_t)BN_num_bytes(order)))
buf_len = i;
if (buf_len < (i = (size_t)BN_num_bytes(cofactor)))
buf_len = i;
if ((seed = EC_GROUP_get0_seed(x)) != NULL)
seed_len = EC_GROUP_get_seed_len(x);
buf_len += 10;
if ((buffer = OPENSSL_malloc(buf_len)) == NULL)
{
reason = ERR_R_MALLOC_FAILURE;
goto err;
}
if (!BIO_indent(bp, off, 128))
goto err;
/* print the 'short name' of the field type */
if (BIO_printf(bp, "Field Type: %s\n", OBJ_nid2sn(tmp_nid))
<= 0)
goto err;
if (is_char_two)
{
/* print the 'short name' of the base type OID */
int basis_type = EC_GROUP_get_basis_type(x);
if (basis_type == 0)
goto err;
if (!BIO_indent(bp, off, 128))
goto err;
if (BIO_printf(bp, "Basis Type: %s\n",
OBJ_nid2sn(basis_type)) <= 0)
goto err;
/* print the polynomial */
if ((p != NULL) && !print(bp, "Polynomial:", p, buffer,
off))
goto err;
}
else
{
if ((p != NULL) && !print(bp, "Prime:", p, buffer,off))
goto err;
}
if ((a != NULL) && !print(bp, "A: ", a, buffer, off))
goto err;
if ((b != NULL) && !print(bp, "B: ", b, buffer, off))
goto err;
if (form == POINT_CONVERSION_COMPRESSED)
{
if ((gen != NULL) && !print(bp, gen_compressed, gen,
buffer, off))
goto err;
}
else if (form == POINT_CONVERSION_UNCOMPRESSED)
{
if ((gen != NULL) && !print(bp, gen_uncompressed, gen,
buffer, off))
goto err;
}
else /* form == POINT_CONVERSION_HYBRID */
{
if ((gen != NULL) && !print(bp, gen_hybrid, gen,
buffer, off))
goto err;
}
if ((order != NULL) && !print(bp, "Order: ", order,
buffer, off)) goto err;
if ((cofactor != NULL) && !print(bp, "Cofactor: ", cofactor,
buffer, off)) goto err;
if (seed && !print_bin(bp, "Seed:", seed, seed_len, off))
goto err;
}
ret=1;
err:
if (!ret)
ECerr(EC_F_ECPKPARAMETERS_PRINT, reason);
if (p)
BN_free(p);
if (a)
BN_free(a);
if (b)
BN_free(b);
if (gen)
BN_free(gen);
if (order)
BN_free(order);
if (cofactor)
BN_free(cofactor);
if (ctx)
BN_CTX_free(ctx);
if (buffer != NULL)
OPENSSL_free(buffer);
return(ret);
}
int EC_GROUP_copy(EC_GROUP *dest, const EC_GROUP *src)
{
EC_EXTRA_DATA *d;
if (dest->meth->group_copy == 0)
{
ECerr(EC_F_EC_GROUP_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
if (dest->meth != src->meth)
{
ECerr(EC_F_EC_GROUP_COPY, EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
if (dest == src)
return 1;
EC_EX_DATA_free_all_data(&dest->extra_data);
for (d = src->extra_data; d != NULL; d = d->next)
{
void *t = d->dup_func(d->data);
if (t == NULL)
return 0;
if (!EC_EX_DATA_set_data(&dest->extra_data, t, d->dup_func, d->free_func, d->clear_free_func))
return 0;
}
if (src->generator != NULL)
{
if (dest->generator == NULL)
{
dest->generator = EC_POINT_new(dest);
if (dest->generator == NULL) return 0;
}
if (!EC_POINT_copy(dest->generator, src->generator)) return 0;
}
else
{
/* src->generator == NULL */
if (dest->generator != NULL)
{
EC_POINT_clear_free(dest->generator);
dest->generator = NULL;
}
}
if (!BN_copy(&dest->order, &src->order)) return 0;
if (!BN_copy(&dest->cofactor, &src->cofactor)) return 0;
dest->curve_name = src->curve_name;
dest->asn1_flag = src->asn1_flag;
dest->asn1_form = src->asn1_form;
if (src->seed)
{
if (dest->seed)
OPENSSL_free(dest->seed);
dest->seed = clBnAlloc( "EC_GROUP_copy",src->seed_len); /* pcg */
if (dest->seed == NULL)
return 0;
if (!memcpy(dest->seed, src->seed, src->seed_len))
return 0;
dest->seed_len = src->seed_len;
}
else
{
if (dest->seed)
OPENSSL_free(dest->seed);
dest->seed = NULL;
dest->seed_len = 0;
}
return dest->meth->group_copy(dest, src);
}
/* Determine the modified width-(w+1) Non-Adjacent Form (wNAF) of 'scalar'.
* This is an array r[] of values that are either zero or odd with an
* absolute value less than 2^w satisfying
* scalar = \sum_j r[j]*2^j
* where at most one of any w+1 consecutive digits is non-zero
* with the exception that the most significant digit may be only
* w-1 zeros away from that next non-zero digit.
*/
static signed char *
compute_wNAF(const BIGNUM * scalar, int w, size_t * ret_len)
{
int window_val;
int ok = 0;
signed char *r = NULL;
int sign = 1;
int bit, next_bit, mask;
size_t len = 0, j;
if (BN_is_zero(scalar)) {
r = malloc(1);
if (!r) {
ECerr(EC_F_COMPUTE_WNAF, ERR_R_MALLOC_FAILURE);
goto err;
}
r[0] = 0;
*ret_len = 1;
return r;
}
if (w <= 0 || w > 7) {
/* 'signed char' can represent integers with
* absolute values less than 2^7 */
ECerr(EC_F_COMPUTE_WNAF, ERR_R_INTERNAL_ERROR);
goto err;
}
bit = 1 << w; /* at most 128 */
next_bit = bit << 1; /* at most 256 */
mask = next_bit - 1; /* at most 255 */
if (BN_is_negative(scalar)) {
sign = -1;
}
if (scalar->d == NULL || scalar->top == 0) {
ECerr(EC_F_COMPUTE_WNAF, ERR_R_INTERNAL_ERROR);
goto err;
}
len = BN_num_bits(scalar);
r = malloc(len + 1); /* modified wNAF may be one digit longer than
* binary representation (*ret_len will be
* set to the actual length, i.e. at most
* BN_num_bits(scalar) + 1) */
if (r == NULL) {
ECerr(EC_F_COMPUTE_WNAF, ERR_R_MALLOC_FAILURE);
goto err;
}
window_val = scalar->d[0] & mask;
j = 0;
while ((window_val != 0) || (j + w + 1 < len)) {
/* if j+w+1 >= len, window_val will not increase */
int digit = 0;
/* 0 <= window_val <= 2^(w+1) */
if (window_val & 1) {
/* 0 < window_val < 2^(w+1) */
if (window_val & bit) {
digit = window_val - next_bit; /* -2^w < digit < 0 */
#if 1 /* modified wNAF */
if (j + w + 1 >= len) {
/*
* special case for generating
* modified wNAFs: no new bits will
* be added into window_val, so using
* a positive digit here will
* decrease the total length of the
* representation
*/
digit = window_val & (mask >> 1); /* 0 < digit < 2^w */
}
#endif
} else {
static EC_GROUP *ec_group_new_from_data(const ec_list_element curve)
{
EC_GROUP *group = NULL;
EC_POINT *P = NULL;
BN_CTX *ctx = NULL;
BIGNUM *p = NULL, *a = NULL, *b = NULL, *x = NULL, *y = NULL, *order =
NULL;
int ok = 0;
int seed_len, param_len;
const EC_METHOD *meth;
const EC_CURVE_DATA *data;
const unsigned char *params;
/* If no curve data curve method must handle everything */
if (curve.data == NULL)
return EC_GROUP_new(curve.meth != NULL ? curve.meth() : NULL);
if ((ctx = BN_CTX_new()) == NULL) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_MALLOC_FAILURE);
goto err;
}
data = curve.data;
seed_len = data->seed_len;
param_len = data->param_len;
params = (const unsigned char *)(data + 1); /* skip header */
params += seed_len; /* skip seed */
if ((p = BN_bin2bn(params + 0 * param_len, param_len, NULL)) == NULL
|| (a = BN_bin2bn(params + 1 * param_len, param_len, NULL)) == NULL
|| (b = BN_bin2bn(params + 2 * param_len, param_len, NULL)) == NULL) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_BN_LIB);
goto err;
}
if (curve.meth != 0) {
meth = curve.meth();
if (((group = EC_GROUP_new(meth)) == NULL) ||
(!(group->meth->group_set_curve(group, p, a, b, ctx)))) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
} else if (data->field_type == NID_X9_62_prime_field) {
if ((group = EC_GROUP_new_curve_GFp(p, a, b, ctx)) == NULL) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
}
#ifndef OPENSSL_NO_EC2M
else { /* field_type ==
* NID_X9_62_characteristic_two_field */
if ((group = EC_GROUP_new_curve_GF2m(p, a, b, ctx)) == NULL) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
}
#endif
if ((P = EC_POINT_new(group)) == NULL) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
if ((x = BN_bin2bn(params + 3 * param_len, param_len, NULL)) == NULL
|| (y = BN_bin2bn(params + 4 * param_len, param_len, NULL)) == NULL) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_BN_LIB);
goto err;
}
if (!EC_POINT_set_affine_coordinates_GFp(group, P, x, y, ctx)) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
if ((order = BN_bin2bn(params + 5 * param_len, param_len, NULL)) == NULL
|| !BN_set_word(x, (BN_ULONG)data->cofactor)) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_BN_LIB);
goto err;
}
if (!EC_GROUP_set_generator(group, P, order, x)) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
if (seed_len) {
if (!EC_GROUP_set_seed(group, params - seed_len, seed_len)) {
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
}
ok = 1;
err:
if (!ok) {
EC_GROUP_free(group);
group = NULL;
}
EC_POINT_free(P);
BN_CTX_free(ctx);
BN_free(p);
BN_free(a);
BN_free(b);
BN_free(order);
BN_free(x);
BN_free(y);
return group;
}
static int pkey_ec_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
{
EC_PKEY_CTX *dctx = ctx->data;
EC_GROUP *group;
switch (type) {
case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID:
group = EC_GROUP_new_by_curve_name(p1);
if (group == NULL) {
ECerr(EC_F_PKEY_EC_CTRL, EC_R_INVALID_CURVE);
return 0;
}
EC_GROUP_free(dctx->gen_group);
dctx->gen_group = group;
return 1;
case EVP_PKEY_CTRL_EC_PARAM_ENC:
if (!dctx->gen_group) {
ECerr(EC_F_PKEY_EC_CTRL, EC_R_NO_PARAMETERS_SET);
return 0;
}
EC_GROUP_set_asn1_flag(dctx->gen_group, p1);
return 1;
#ifndef OPENSSL_NO_EC
case EVP_PKEY_CTRL_EC_ECDH_COFACTOR:
if (p1 == -2) {
if (dctx->cofactor_mode != -1)
return dctx->cofactor_mode;
else {
EC_KEY *ec_key = ctx->pkey->pkey.ec;
return EC_KEY_get_flags(ec_key) & EC_FLAG_COFACTOR_ECDH ? 1 :
0;
}
} else if (p1 < -1 || p1 > 1)
return -2;
dctx->cofactor_mode = p1;
if (p1 != -1) {
EC_KEY *ec_key = ctx->pkey->pkey.ec;
if (!ec_key->group)
return -2;
/* If cofactor is 1 cofactor mode does nothing */
if (BN_is_one(ec_key->group->cofactor))
return 1;
if (!dctx->co_key) {
dctx->co_key = EC_KEY_dup(ec_key);
if (!dctx->co_key)
return 0;
}
if (p1)
EC_KEY_set_flags(dctx->co_key, EC_FLAG_COFACTOR_ECDH);
else
EC_KEY_clear_flags(dctx->co_key, EC_FLAG_COFACTOR_ECDH);
} else {
EC_KEY_free(dctx->co_key);
dctx->co_key = NULL;
}
return 1;
#endif
case EVP_PKEY_CTRL_EC_KDF_TYPE:
if (p1 == -2)
return dctx->kdf_type;
if (p1 != EVP_PKEY_ECDH_KDF_NONE && p1 != EVP_PKEY_ECDH_KDF_X9_62)
return -2;
dctx->kdf_type = p1;
return 1;
#ifndef OPENSSL_NO_SM2
case EVP_PKEY_CTRL_EC_SCHEME:
if (p1 == -2) {
return dctx->ec_scheme;
}
if (p1 != NID_secg_scheme && p1 != NID_sm_scheme) {
ECerr(EC_F_PKEY_EC_CTRL, EC_R_INVALID_EC_SCHEME);
return 0;
}
dctx->ec_scheme = p1;
return 1;
case EVP_PKEY_CTRL_SIGNER_ID:
if (!p2 || !strlen((char *)p2) || strlen((char *)p2) > SM2_MAX_ID_LENGTH) {
ECerr(EC_F_PKEY_EC_CTRL, EC_R_INVALID_SIGNER_ID);
return 0;
} else {
char *id = NULL;
if (!(id = OPENSSL_strdup((char *)p2))) {
ECerr(EC_F_PKEY_EC_CTRL, ERR_R_MALLOC_FAILURE);
return 0;
}
if (dctx->signer_id)
OPENSSL_free(dctx->signer_id);
dctx->signer_id = id;
if (dctx->ec_scheme == NID_sm_scheme) {
EC_KEY *ec_key = ctx->pkey->pkey.ec;
unsigned char zid[SM3_DIGEST_LENGTH];
size_t zidlen = SM3_DIGEST_LENGTH;
if (!SM2_compute_id_digest(EVP_sm3(), dctx->signer_id,
strlen(dctx->signer_id), zid, &zidlen, ec_key)) {
ECerr(EC_F_PKEY_EC_CTRL, ERR_R_SM2_LIB);
return 0;
}
if (!dctx->signer_zid) {
if (!(dctx->signer_zid = OPENSSL_malloc(zidlen))) {
ECerr(EC_F_PKEY_EC_CTRL, ERR_R_MALLOC_FAILURE);
return 0;
}
}
memcpy(dctx->signer_zid, zid, zidlen);
}
}
return 1;
case EVP_PKEY_CTRL_GET_SIGNER_ID:
*(const char **)p2 = dctx->signer_id;
return 1;
case EVP_PKEY_CTRL_GET_SIGNER_ZID:
if (dctx->ec_scheme != NID_sm_scheme) {
*(const unsigned char **)p2 = NULL;
return -2;
}
if (!dctx->signer_zid) {
EC_KEY *ec_key = ctx->pkey->pkey.ec;
unsigned char *zid;
size_t zidlen = SM3_DIGEST_LENGTH;
if (!(zid = OPENSSL_malloc(zidlen))) {
ECerr(EC_F_PKEY_EC_CTRL, ERR_R_MALLOC_FAILURE);
return 0;
}
if (!SM2_compute_id_digest(EVP_sm3(), SM2_DEFAULT_ID,
SM2_DEFAULT_ID_LENGTH, zid, &zidlen, ec_key)) {
ECerr(EC_F_PKEY_EC_CTRL, ERR_R_SM2_LIB);
OPENSSL_free(zid);
return 0;
}
dctx->signer_zid = zid;
}
*(const unsigned char **)p2 = dctx->signer_zid;
return 1;
case EVP_PKEY_CTRL_EC_ENCRYPT_PARAM:
if (p1 == -2) {
return dctx->ec_encrypt_param;
}
dctx->ec_encrypt_param = p1;
return 1;
#endif
case EVP_PKEY_CTRL_EC_KDF_MD:
dctx->kdf_md = p2;
return 1;
case EVP_PKEY_CTRL_GET_EC_KDF_MD:
*(const EVP_MD **)p2 = dctx->kdf_md;
return 1;
case EVP_PKEY_CTRL_EC_KDF_OUTLEN:
if (p1 <= 0)
return -2;
dctx->kdf_outlen = (size_t)p1;
return 1;
case EVP_PKEY_CTRL_GET_EC_KDF_OUTLEN:
*(int *)p2 = dctx->kdf_outlen;
return 1;
case EVP_PKEY_CTRL_EC_KDF_UKM:
OPENSSL_free(dctx->kdf_ukm);
dctx->kdf_ukm = p2;
if (p2)
dctx->kdf_ukmlen = p1;
else
dctx->kdf_ukmlen = 0;
return 1;
case EVP_PKEY_CTRL_GET_EC_KDF_UKM:
*(unsigned char **)p2 = dctx->kdf_ukm;
return dctx->kdf_ukmlen;
case EVP_PKEY_CTRL_MD:
if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
#ifndef OPENSSL_NO_SM3
EVP_MD_type((const EVP_MD *)p2) != NID_sm3 &&
#endif
EVP_MD_type((const EVP_MD *)p2) != NID_ecdsa_with_SHA1 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha256 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha384 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha512) {
ECerr(EC_F_PKEY_EC_CTRL, EC_R_INVALID_DIGEST_TYPE);
return 0;
}
dctx->md = p2;
return 1;
case EVP_PKEY_CTRL_GET_MD:
*(const EVP_MD **)p2 = dctx->md;
return 1;
case EVP_PKEY_CTRL_PEER_KEY:
/* Default behaviour is OK */
case EVP_PKEY_CTRL_DIGESTINIT:
case EVP_PKEY_CTRL_PKCS7_SIGN:
case EVP_PKEY_CTRL_CMS_SIGN:
return 1;
default:
return -2;
}
}
/* Setup EVP_PKEY using public, private or generation */
static int ecx_key_op(EVP_PKEY *pkey, int id, const X509_ALGOR *palg,
const unsigned char *p, int plen, ecx_key_op_t op)
{
ECX_KEY *key = NULL;
unsigned char *privkey, *pubkey;
if (op != KEY_OP_KEYGEN) {
if (palg != NULL) {
int ptype;
/* Algorithm parameters must be absent */
X509_ALGOR_get0(NULL, &ptype, NULL, palg);
if (ptype != V_ASN1_UNDEF) {
ECerr(EC_F_ECX_KEY_OP, EC_R_INVALID_ENCODING);
return 0;
}
}
if (p == NULL || plen != KEYLENID(id)) {
ECerr(EC_F_ECX_KEY_OP, EC_R_INVALID_ENCODING);
return 0;
}
}
key = OPENSSL_zalloc(sizeof(*key));
if (key == NULL) {
ECerr(EC_F_ECX_KEY_OP, ERR_R_MALLOC_FAILURE);
return 0;
}
pubkey = key->pubkey;
if (op == KEY_OP_PUBLIC) {
memcpy(pubkey, p, plen);
} else {
privkey = key->privkey = OPENSSL_secure_malloc(KEYLENID(id));
if (privkey == NULL) {
ECerr(EC_F_ECX_KEY_OP, ERR_R_MALLOC_FAILURE);
goto err;
}
if (op == KEY_OP_KEYGEN) {
if (RAND_priv_bytes(privkey, KEYLENID(id)) <= 0) {
OPENSSL_secure_free(privkey);
key->privkey = NULL;
goto err;
}
if (id == EVP_PKEY_X25519) {
privkey[0] &= 248;
privkey[X25519_KEYLEN - 1] &= 127;
privkey[X25519_KEYLEN - 1] |= 64;
} else if (id == EVP_PKEY_X448) {
privkey[0] &= 252;
privkey[X448_KEYLEN - 1] |= 128;
}
} else {
memcpy(privkey, p, KEYLENID(id));
}
switch (id) {
case EVP_PKEY_X25519:
X25519_public_from_private(pubkey, privkey);
break;
case EVP_PKEY_ED25519:
ED25519_public_from_private(pubkey, privkey);
break;
case EVP_PKEY_X448:
X448_public_from_private(pubkey, privkey);
break;
case EVP_PKEY_ED448:
ED448_public_from_private(pubkey, privkey);
break;
}
}
EVP_PKEY_assign(pkey, id, key);
return 1;
err:
OPENSSL_free(key);
return 0;
}
static int do_EC_KEY_print(BIO *bp, const EC_KEY *x, int off, ec_print_t ktype)
{
const char *ecstr;
unsigned char *priv = NULL, *pub = NULL;
size_t privlen = 0, publen = 0;
int ret = 0;
const EC_GROUP *group;
if (x == NULL || (group = EC_KEY_get0_group(x)) == NULL) {
ECerr(EC_F_DO_EC_KEY_PRINT, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if (ktype != EC_KEY_PRINT_PARAM && EC_KEY_get0_public_key(x) != NULL) {
publen = EC_KEY_key2buf(x, EC_KEY_get_conv_form(x), &pub, NULL);
if (publen == 0)
goto err;
}
if (ktype == EC_KEY_PRINT_PRIVATE && EC_KEY_get0_private_key(x) != NULL) {
privlen = EC_KEY_priv2buf(x, &priv);
if (privlen == 0)
goto err;
}
if (ktype == EC_KEY_PRINT_PRIVATE)
ecstr = "Private-Key";
else if (ktype == EC_KEY_PRINT_PUBLIC)
ecstr = "Public-Key";
else
ecstr = "ECDSA-Parameters";
if (!BIO_indent(bp, off, 128))
goto err;
if (BIO_printf(bp, "%s: (%d bit)\n", ecstr,
EC_GROUP_order_bits(group)) <= 0)
goto err;
if (privlen != 0) {
if (BIO_printf(bp, "%*spriv:\n", off, "") <= 0)
goto err;
if (ASN1_buf_print(bp, priv, privlen, off + 4) == 0)
goto err;
}
if (publen != 0) {
if (BIO_printf(bp, "%*spub:\n", off, "") <= 0)
goto err;
if (ASN1_buf_print(bp, pub, publen, off + 4) == 0)
goto err;
}
if (!ECPKParameters_print(bp, group, off))
goto err;
ret = 1;
err:
if (!ret)
ECerr(EC_F_DO_EC_KEY_PRINT, ERR_R_EC_LIB);
OPENSSL_clear_free(priv, privlen);
OPENSSL_free(pub);
return ret;
}
/*-
* This implementation is based on the following primitives in the IEEE 1363 standard:
* - ECKAS-DH1
* - ECSVDP-DH
* Finally an optional KDF is applied.
*/
int ossl_ecdh_compute_key(void *out, size_t outlen, const EC_POINT *pub_key,
const EC_KEY *ecdh,
void *(*KDF) (const void *in, size_t inlen,
void *out, size_t *outlen))
{
BN_CTX *ctx;
EC_POINT *tmp = NULL;
BIGNUM *x = NULL, *y = NULL;
const BIGNUM *priv_key;
const EC_GROUP *group;
int ret = -1;
size_t buflen, len;
unsigned char *buf = NULL;
if (outlen > INT_MAX) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, ERR_R_MALLOC_FAILURE); /* sort of,
* anyway */
return -1;
}
if (ecdh->group->meth->ecdh_compute_key != 0)
return ecdh->group->meth->ecdh_compute_key(out, outlen, pub_key, ecdh,
KDF);
if ((ctx = BN_CTX_new()) == NULL)
goto err;
BN_CTX_start(ctx);
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
priv_key = EC_KEY_get0_private_key(ecdh);
if (priv_key == NULL) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, EC_R_NO_PRIVATE_VALUE);
goto err;
}
group = EC_KEY_get0_group(ecdh);
if (EC_KEY_get_flags(ecdh) & EC_FLAG_COFACTOR_ECDH) {
if (!EC_GROUP_get_cofactor(group, x, NULL) ||
!BN_mul(x, x, priv_key, ctx)) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, ERR_R_MALLOC_FAILURE);
goto err;
}
priv_key = x;
}
if ((tmp = EC_POINT_new(group)) == NULL) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, ERR_R_MALLOC_FAILURE);
goto err;
}
if (!EC_POINT_mul(group, tmp, NULL, pub_key, priv_key, ctx)) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, EC_R_POINT_ARITHMETIC_FAILURE);
goto err;
}
if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) ==
NID_X9_62_prime_field) {
if (!EC_POINT_get_affine_coordinates_GFp(group, tmp, x, y, ctx)) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, EC_R_POINT_ARITHMETIC_FAILURE);
goto err;
}
}
#ifndef OPENSSL_NO_EC2M
else {
if (!EC_POINT_get_affine_coordinates_GF2m(group, tmp, x, y, ctx)) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, EC_R_POINT_ARITHMETIC_FAILURE);
goto err;
}
}
#endif
buflen = (EC_GROUP_get_degree(group) + 7) / 8;
len = BN_num_bytes(x);
if (len > buflen) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, ERR_R_INTERNAL_ERROR);
goto err;
}
if ((buf = OPENSSL_malloc(buflen)) == NULL) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, ERR_R_MALLOC_FAILURE);
goto err;
}
memset(buf, 0, buflen - len);
if (len != (size_t)BN_bn2bin(x, buf + buflen - len)) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, ERR_R_BN_LIB);
goto err;
}
if (KDF != 0) {
if (KDF(buf, buflen, out, &outlen) == NULL) {
ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, EC_R_KDF_FAILED);
goto err;
}
ret = outlen;
} else {
/* no KDF, just copy as much as we can */
if (outlen > buflen)
outlen = buflen;
memcpy(out, buf, outlen);
ret = outlen;
}
err:
EC_POINT_free(tmp);
if (ctx)
BN_CTX_end(ctx);
BN_CTX_free(ctx);
OPENSSL_free(buf);
return (ret);
}
int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
const ECDSA_SIG *sig, EC_KEY *eckey)
{
int ret = -1, i;
BN_CTX *ctx;
const BIGNUM *order;
BIGNUM *u1, *u2, *m, *X;
EC_POINT *point = NULL;
const EC_GROUP *group;
const EC_POINT *pub_key;
/* check input values */
if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL ||
(pub_key = EC_KEY_get0_public_key(eckey)) == NULL || sig == NULL) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, EC_R_MISSING_PARAMETERS);
return -1;
}
if (!EC_KEY_can_sign(eckey)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
return -1;
}
ctx = BN_CTX_new();
if (ctx == NULL) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_MALLOC_FAILURE);
return -1;
}
BN_CTX_start(ctx);
u1 = BN_CTX_get(ctx);
u2 = BN_CTX_get(ctx);
m = BN_CTX_get(ctx);
X = BN_CTX_get(ctx);
if (X == NULL) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
goto err;
}
order = EC_GROUP_get0_order(group);
if (order == NULL) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);
goto err;
}
if (BN_is_zero(sig->r) || BN_is_negative(sig->r) ||
BN_ucmp(sig->r, order) >= 0 || BN_is_zero(sig->s) ||
BN_is_negative(sig->s) || BN_ucmp(sig->s, order) >= 0) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, EC_R_BAD_SIGNATURE);
ret = 0; /* signature is invalid */
goto err;
}
/* calculate tmp1 = inv(S) mod order */
/* Check if optimized inverse is implemented */
if (EC_GROUP_do_inverse_ord(group, u2, sig->s, ctx) == 0) {
if (!BN_mod_inverse(u2, sig->s, order, ctx)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
goto err;
}
}
/* digest -> m */
i = BN_num_bits(order);
/*
* Need to truncate digest if it is too long: first truncate whole bytes.
*/
if (8 * dgst_len > i)
dgst_len = (i + 7) / 8;
if (!BN_bin2bn(dgst, dgst_len, m)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
goto err;
}
/* If still too long truncate remaining bits with a shift */
if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
goto err;
}
/* u1 = m * tmp mod order */
if (!BN_mod_mul(u1, m, u2, order, ctx)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
goto err;
}
/* u2 = r * w mod q */
if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
goto err;
}
if ((point = EC_POINT_new(group)) == NULL) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_MALLOC_FAILURE);
goto err;
}
if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);
goto err;
}
if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) ==
NID_X9_62_prime_field) {
if (!EC_POINT_get_affine_coordinates_GFp(group, point, X, NULL, ctx)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);
goto err;
}
}
#ifndef OPENSSL_NO_EC2M
else { /* NID_X9_62_characteristic_two_field */
if (!EC_POINT_get_affine_coordinates_GF2m(group, point, X, NULL, ctx)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);
goto err;
}
}
#endif
if (!BN_nnmod(u1, X, order, ctx)) {
ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
goto err;
}
/* if the signature is correct u1 is equal to sig->r */
ret = (BN_ucmp(u1, sig->r) == 0);
err:
BN_CTX_end(ctx);
BN_CTX_free(ctx);
EC_POINT_free(point);
return ret;
}
static int
eckey_priv_decode(EVP_PKEY * pkey, PKCS8_PRIV_KEY_INFO * p8)
{
const unsigned char *p = NULL;
void *pval;
int ptype, pklen;
EC_KEY *eckey = NULL;
X509_ALGOR *palg;
if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
return 0;
X509_ALGOR_get0(NULL, &ptype, &pval, palg);
eckey = eckey_type2param(ptype, pval);
if (!eckey)
goto ecliberr;
/* We have parameters now set private key */
if (!d2i_ECPrivateKey(&eckey, &p, pklen)) {
ECerr(EC_F_ECKEY_PRIV_DECODE, EC_R_DECODE_ERROR);
goto ecerr;
}
/* calculate public key (if necessary) */
if (EC_KEY_get0_public_key(eckey) == NULL) {
const BIGNUM *priv_key;
const EC_GROUP *group;
EC_POINT *pub_key;
/*
* the public key was not included in the SEC1 private key =>
* calculate the public key
*/
group = EC_KEY_get0_group(eckey);
pub_key = EC_POINT_new(group);
if (pub_key == NULL) {
ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
goto ecliberr;
}
if (!EC_POINT_copy(pub_key, EC_GROUP_get0_generator(group))) {
EC_POINT_free(pub_key);
ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
goto ecliberr;
}
priv_key = EC_KEY_get0_private_key(eckey);
if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, NULL)) {
EC_POINT_free(pub_key);
ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
goto ecliberr;
}
if (EC_KEY_set_public_key(eckey, pub_key) == 0) {
EC_POINT_free(pub_key);
ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
goto ecliberr;
}
EC_POINT_free(pub_key);
}
EVP_PKEY_assign_EC_KEY(pkey, eckey);
return 1;
ecliberr:
ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB);
ecerr:
if (eckey)
EC_KEY_free(eckey);
return 0;
}
EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src)
{
if (dest == NULL || src == NULL) {
ECerr(EC_F_EC_KEY_COPY, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
if (src->meth != dest->meth) {
if (dest->meth->finish != NULL)
dest->meth->finish(dest);
if (dest->group && dest->group->meth->keyfinish)
dest->group->meth->keyfinish(dest);
#ifndef OPENSSL_NO_ENGINE
if (ENGINE_finish(dest->engine) == 0)
return 0;
dest->engine = NULL;
#endif
}
/* copy the parameters */
if (src->group != NULL) {
const EC_METHOD *meth = EC_GROUP_method_of(src->group);
/* clear the old group */
EC_GROUP_free(dest->group);
dest->group = EC_GROUP_new(meth);
if (dest->group == NULL)
return NULL;
if (!EC_GROUP_copy(dest->group, src->group))
return NULL;
/* copy the public key */
if (src->pub_key != NULL) {
EC_POINT_free(dest->pub_key);
dest->pub_key = EC_POINT_new(src->group);
if (dest->pub_key == NULL)
return NULL;
if (!EC_POINT_copy(dest->pub_key, src->pub_key))
return NULL;
}
/* copy the private key */
if (src->priv_key != NULL) {
if (dest->priv_key == NULL) {
dest->priv_key = BN_new();
if (dest->priv_key == NULL)
return NULL;
}
if (!BN_copy(dest->priv_key, src->priv_key))
return NULL;
if (src->group->meth->keycopy
&& src->group->meth->keycopy(dest, src) == 0)
return NULL;
}
}
/* copy the rest */
dest->enc_flag = src->enc_flag;
dest->conv_form = src->conv_form;
dest->version = src->version;
dest->flags = src->flags;
if (!CRYPTO_dup_ex_data(CRYPTO_EX_INDEX_EC_KEY,
&dest->ex_data, &src->ex_data))
return NULL;
if (src->meth != dest->meth) {
#ifndef OPENSSL_NO_ENGINE
if (src->engine != NULL && ENGINE_init(src->engine) == 0)
return NULL;
dest->engine = src->engine;
#endif
dest->meth = src->meth;
}
if (src->meth->copy != NULL && src->meth->copy(dest, src) == 0)
return NULL;
return dest;
}
static int
do_EC_KEY_print(BIO * bp, const EC_KEY * x, int off, int ktype)
{
unsigned char *buffer = NULL;
const char *ecstr;
size_t buf_len = 0, i;
int ret = 0, reason = ERR_R_BIO_LIB;
BIGNUM *pub_key = NULL, *order = NULL;
BN_CTX *ctx = NULL;
const EC_GROUP *group;
const EC_POINT *public_key;
const BIGNUM *priv_key;
if (x == NULL || (group = EC_KEY_get0_group(x)) == NULL) {
reason = ERR_R_PASSED_NULL_PARAMETER;
goto err;
}
ctx = BN_CTX_new();
if (ctx == NULL) {
reason = ERR_R_MALLOC_FAILURE;
goto err;
}
if (ktype > 0) {
public_key = EC_KEY_get0_public_key(x);
if ((pub_key = EC_POINT_point2bn(group, public_key,
EC_KEY_get_conv_form(x), NULL, ctx)) == NULL) {
reason = ERR_R_EC_LIB;
goto err;
}
if (pub_key)
buf_len = (size_t) BN_num_bytes(pub_key);
}
if (ktype == 2) {
priv_key = EC_KEY_get0_private_key(x);
if (priv_key && (i = (size_t) BN_num_bytes(priv_key)) > buf_len)
buf_len = i;
} else
priv_key = NULL;
if (ktype > 0) {
buf_len += 10;
if ((buffer = malloc(buf_len)) == NULL) {
reason = ERR_R_MALLOC_FAILURE;
goto err;
}
}
if (ktype == 2)
ecstr = "Private-Key";
else if (ktype == 1)
ecstr = "Public-Key";
else
ecstr = "ECDSA-Parameters";
if (!BIO_indent(bp, off, 128))
goto err;
if ((order = BN_new()) == NULL)
goto err;
if (!EC_GROUP_get_order(group, order, NULL))
goto err;
if (BIO_printf(bp, "%s: (%d bit)\n", ecstr,
BN_num_bits(order)) <= 0)
goto err;
if ((priv_key != NULL) && !ASN1_bn_print(bp, "priv:", priv_key,
buffer, off))
goto err;
if ((pub_key != NULL) && !ASN1_bn_print(bp, "pub: ", pub_key,
buffer, off))
goto err;
if (!ECPKParameters_print(bp, group, off))
goto err;
ret = 1;
err:
if (!ret)
ECerr(EC_F_DO_EC_KEY_PRINT, reason);
BN_free(pub_key);
BN_free(order);
BN_CTX_free(ctx);
free(buffer);
return (ret);
}
int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, EC_POINT *points[], BN_CTX *ctx)
{
BN_CTX *new_ctx = NULL;
BIGNUM *tmp0, *tmp1;
size_t pow2 = 0;
BIGNUM **heap = NULL;
size_t i;
int ret = 0;
if (num == 0)
return 1;
if (ctx == NULL)
{
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
BN_CTX_start(ctx);
tmp0 = BN_CTX_get(ctx);
tmp1 = BN_CTX_get(ctx);
if (tmp0 == NULL || tmp1 == NULL) goto err;
/* Before converting the individual points, compute inverses of all Z values.
* Modular inversion is rather slow, but luckily we can do with a single
* explicit inversion, plus about 3 multiplications per input value.
*/
pow2 = 1;
while (num > pow2)
pow2 <<= 1;
/* Now pow2 is the smallest power of 2 satifsying pow2 >= num.
* We need twice that. */
pow2 <<= 1;
heap = OPENSSL_malloc(pow2 * sizeof heap[0]);
if (heap == NULL) goto err;
/* The array is used as a binary tree, exactly as in heapsort:
*
* heap[1]
* heap[2] heap[3]
* heap[4] heap[5] heap[6] heap[7]
* heap[8]heap[9] heap[10]heap[11] heap[12]heap[13] heap[14] heap[15]
*
* We put the Z's in the last line;
* then we set each other node to the product of its two child-nodes (where
* empty or 0 entries are treated as ones);
* then we invert heap[1];
* then we invert each other node by replacing it by the product of its
* parent (after inversion) and its sibling (before inversion).
*/
heap[0] = NULL;
for (i = pow2/2 - 1; i > 0; i--)
heap[i] = NULL;
for (i = 0; i < num; i++)
heap[pow2/2 + i] = &points[i]->Z;
for (i = pow2/2 + num; i < pow2; i++)
heap[i] = NULL;
/* set each node to the product of its children */
for (i = pow2/2 - 1; i > 0; i--)
{
heap[i] = BN_new();
if (heap[i] == NULL) goto err;
if (heap[2*i] != NULL)
{
if ((heap[2*i + 1] == NULL) || BN_is_zero(heap[2*i + 1]))
{
if (!BN_copy(heap[i], heap[2*i])) goto err;
}
else
{
if (BN_is_zero(heap[2*i]))
{
if (!BN_copy(heap[i], heap[2*i + 1])) goto err;
}
else
{
if (!group->meth->field_mul(group, heap[i],
heap[2*i], heap[2*i + 1], ctx)) goto err;
}
}
}
}
/* invert heap[1] */
if (!BN_is_zero(heap[1]))
{
if (!BN_mod_inverse(heap[1], heap[1], &group->field, ctx))
{
ECerr(EC_F_EC_GFP_SIMPLE_POINTS_MAKE_AFFINE, ERR_R_BN_LIB);
goto err;
}
}
if (group->meth->field_encode != 0)
{
/* in the Montgomery case, we just turned R*H (representing H)
* into 1/(R*H), but we need R*(1/H) (representing 1/H);
* i.e. we have need to multiply by the Montgomery factor twice */
if (!group->meth->field_encode(group, heap[1], heap[1], ctx)) goto err;
if (!group->meth->field_encode(group, heap[1], heap[1], ctx)) goto err;
}
/* set other heap[i]'s to their inverses */
for (i = 2; i < pow2/2 + num; i += 2)
{
/* i is even */
if ((heap[i + 1] != NULL) && !BN_is_zero(heap[i + 1]))
{
if (!group->meth->field_mul(group, tmp0, heap[i/2], heap[i + 1], ctx)) goto err;
if (!group->meth->field_mul(group, tmp1, heap[i/2], heap[i], ctx)) goto err;
if (!BN_copy(heap[i], tmp0)) goto err;
if (!BN_copy(heap[i + 1], tmp1)) goto err;
}
else
{
if (!BN_copy(heap[i], heap[i/2])) goto err;
}
}
/* we have replaced all non-zero Z's by their inverses, now fix up all the points */
for (i = 0; i < num; i++)
{
EC_POINT *p = points[i];
if (!BN_is_zero(&p->Z))
{
/* turn (X, Y, 1/Z) into (X/Z^2, Y/Z^3, 1) */
if (!group->meth->field_sqr(group, tmp1, &p->Z, ctx)) goto err;
if (!group->meth->field_mul(group, &p->X, &p->X, tmp1, ctx)) goto err;
if (!group->meth->field_mul(group, tmp1, tmp1, &p->Z, ctx)) goto err;
if (!group->meth->field_mul(group, &p->Y, &p->Y, tmp1, ctx)) goto err;
if (group->meth->field_set_to_one != 0)
{
if (!group->meth->field_set_to_one(group, &p->Z, ctx)) goto err;
}
else
{
if (!BN_one(&p->Z)) goto err;
}
p->Z_is_one = 1;
}
}
ret = 1;
err:
BN_CTX_end(ctx);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
if (heap != NULL)
{
/* heap[pow2/2] .. heap[pow2-1] have not been allocated locally! */
for (i = pow2/2 - 1; i > 0; i--)
{
if (heap[i] != NULL)
BN_clear_free(heap[i]);
}
OPENSSL_free(heap);
}
return ret;
}
int EC_KEY_print(BIO *bp, const EC_KEY *x, int off)
{
unsigned char *buffer=NULL;
size_t buf_len=0, i;
int ret=0, reason=ERR_R_BIO_LIB;
BIGNUM *pub_key=NULL, *order=NULL;
BN_CTX *ctx=NULL;
const EC_GROUP *group;
const EC_POINT *public_key;
const BIGNUM *priv_key;
if (x == NULL || (group = EC_KEY_get0_group(x)) == NULL)
{
reason = ERR_R_PASSED_NULL_PARAMETER;
goto err;
}
public_key = EC_KEY_get0_public_key(x);
if ((pub_key = EC_POINT_point2bn(group, public_key,
EC_KEY_get_conv_form(x), NULL, ctx)) == NULL)
{
reason = ERR_R_EC_LIB;
goto err;
}
buf_len = (size_t)BN_num_bytes(pub_key);
priv_key = EC_KEY_get0_private_key(x);
if (priv_key != NULL)
{
if ((i = (size_t)BN_num_bytes(priv_key)) > buf_len)
buf_len = i;
}
buf_len += 10;
if ((buffer = OPENSSL_malloc(buf_len)) == NULL)
{
reason = ERR_R_MALLOC_FAILURE;
goto err;
}
if (priv_key != NULL)
{
if (!BIO_indent(bp, off, 128))
goto err;
if ((order = BN_new()) == NULL)
goto err;
if (!EC_GROUP_get_order(group, order, NULL))
goto err;
if (BIO_printf(bp, "Private-Key: (%d bit)\n",
BN_num_bits(order)) <= 0) goto err;
}
if ((priv_key != NULL) && !print(bp, "priv:", priv_key,
buffer, off))
goto err;
if ((pub_key != NULL) && !print(bp, "pub: ", pub_key,
buffer, off))
goto err;
if (!ECPKParameters_print(bp, group, off))
goto err;
ret=1;
err:
if (!ret)
ECerr(EC_F_EC_KEY_PRINT, reason);
if (pub_key)
BN_free(pub_key);
if (order)
BN_free(order);
if (ctx)
BN_CTX_free(ctx);
if (buffer != NULL)
OPENSSL_free(buffer);
return(ret);
}
int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num,
EC_POINT *points[], BN_CTX *ctx)
{
BN_CTX *new_ctx = NULL;
BIGNUM *tmp, *tmp_Z;
BIGNUM **prod_Z = NULL;
size_t i;
int ret = 0;
if (num == 0)
return 1;
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
BN_CTX_start(ctx);
tmp = BN_CTX_get(ctx);
tmp_Z = BN_CTX_get(ctx);
if (tmp == NULL || tmp_Z == NULL)
goto err;
prod_Z = OPENSSL_malloc(num * sizeof prod_Z[0]);
if (prod_Z == NULL)
goto err;
for (i = 0; i < num; i++) {
prod_Z[i] = BN_new();
if (prod_Z[i] == NULL)
goto err;
}
/*
* Set each prod_Z[i] to the product of points[0]->Z .. points[i]->Z,
* skipping any zero-valued inputs (pretend that they're 1).
*/
if (!BN_is_zero(&points[0]->Z)) {
if (!BN_copy(prod_Z[0], &points[0]->Z))
goto err;
} else {
if (group->meth->field_set_to_one != 0) {
if (!group->meth->field_set_to_one(group, prod_Z[0], ctx))
goto err;
} else {
if (!BN_one(prod_Z[0]))
goto err;
}
}
for (i = 1; i < num; i++) {
if (!BN_is_zero(&points[i]->Z)) {
if (!group->meth->field_mul(group, prod_Z[i], prod_Z[i - 1],
&points[i]->Z, ctx))
goto err;
} else {
if (!BN_copy(prod_Z[i], prod_Z[i - 1]))
goto err;
}
}
/*
* Now use a single explicit inversion to replace every non-zero
* points[i]->Z by its inverse.
*/
if (!BN_mod_inverse(tmp, prod_Z[num - 1], &group->field, ctx)) {
ECerr(EC_F_EC_GFP_SIMPLE_POINTS_MAKE_AFFINE, ERR_R_BN_LIB);
goto err;
}
if (group->meth->field_encode != 0) {
/*
* In the Montgomery case, we just turned R*H (representing H) into
* 1/(R*H), but we need R*(1/H) (representing 1/H); i.e. we need to
* multiply by the Montgomery factor twice.
*/
if (!group->meth->field_encode(group, tmp, tmp, ctx))
goto err;
if (!group->meth->field_encode(group, tmp, tmp, ctx))
goto err;
}
for (i = num - 1; i > 0; --i) {
/*
* Loop invariant: tmp is the product of the inverses of points[0]->Z
* .. points[i]->Z (zero-valued inputs skipped).
*/
if (!BN_is_zero(&points[i]->Z)) {
/*
* Set tmp_Z to the inverse of points[i]->Z (as product of Z
* inverses 0 .. i, Z values 0 .. i - 1).
*/
if (!group->
meth->field_mul(group, tmp_Z, prod_Z[i - 1], tmp, ctx))
goto err;
/*
* Update tmp to satisfy the loop invariant for i - 1.
*/
if (!group->meth->field_mul(group, tmp, tmp, &points[i]->Z, ctx))
goto err;
/* Replace points[i]->Z by its inverse. */
if (!BN_copy(&points[i]->Z, tmp_Z))
goto err;
}
}
if (!BN_is_zero(&points[0]->Z)) {
/* Replace points[0]->Z by its inverse. */
if (!BN_copy(&points[0]->Z, tmp))
goto err;
}
/* Finally, fix up the X and Y coordinates for all points. */
for (i = 0; i < num; i++) {
EC_POINT *p = points[i];
if (!BN_is_zero(&p->Z)) {
/* turn (X, Y, 1/Z) into (X/Z^2, Y/Z^3, 1) */
if (!group->meth->field_sqr(group, tmp, &p->Z, ctx))
goto err;
if (!group->meth->field_mul(group, &p->X, &p->X, tmp, ctx))
goto err;
if (!group->meth->field_mul(group, tmp, tmp, &p->Z, ctx))
goto err;
if (!group->meth->field_mul(group, &p->Y, &p->Y, tmp, ctx))
goto err;
if (group->meth->field_set_to_one != 0) {
if (!group->meth->field_set_to_one(group, &p->Z, ctx))
goto err;
} else {
if (!BN_one(&p->Z))
goto err;
}
p->Z_is_one = 1;
}
}
ret = 1;
err:
BN_CTX_end(ctx);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
if (prod_Z != NULL) {
for (i = 0; i < num; i++) {
if (prod_Z[i] == NULL)
break;
BN_clear_free(prod_Z[i]);
}
OPENSSL_free(prod_Z);
}
return ret;
}
/* Computes scalar*point and stores the result in r.
* point can not equal r.
* Uses a modified algorithm 2P of
* Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over
* GF(2^m) without precomputation" (CHES '99, LNCS 1717).
*
* To protect against side-channel attack the function uses constant time swap,
* avoiding conditional branches.
*/
static int ec_GF2m_montgomery_point_multiply(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
const EC_POINT *point, BN_CTX *ctx)
{
BIGNUM *x1, *x2, *z1, *z2;
int ret = 0, i;
BN_ULONG mask,word;
if (r == point)
{
ECerr(EC_F_EC_GF2M_MONTGOMERY_POINT_MULTIPLY, EC_R_INVALID_ARGUMENT);
return 0;
}
/* if result should be point at infinity */
if ((scalar == NULL) || BN_is_zero(scalar) || (point == NULL) ||
EC_POINT_is_at_infinity(group, point))
{
return EC_POINT_set_to_infinity(group, r);
}
/* only support affine coordinates */
if (!point->Z_is_one) return 0;
/* Since point_multiply is static we can guarantee that ctx != NULL. */
BN_CTX_start(ctx);
x1 = BN_CTX_get(ctx);
z1 = BN_CTX_get(ctx);
if (z1 == NULL) goto err;
x2 = &r->X;
z2 = &r->Y;
bn_wexpand(x1, group->field.top);
bn_wexpand(z1, group->field.top);
bn_wexpand(x2, group->field.top);
bn_wexpand(z2, group->field.top);
if (!BN_GF2m_mod_arr(x1, &point->X, group->poly)) goto err; /* x1 = x */
if (!BN_one(z1)) goto err; /* z1 = 1 */
if (!group->meth->field_sqr(group, z2, x1, ctx)) goto err; /* z2 = x1^2 = x^2 */
if (!group->meth->field_sqr(group, x2, z2, ctx)) goto err;
if (!BN_GF2m_add(x2, x2, &group->b)) goto err; /* x2 = x^4 + b */
/* find top most bit and go one past it */
i = scalar->top - 1;
mask = BN_TBIT;
word = scalar->d[i];
while (!(word & mask)) mask >>= 1;
mask >>= 1;
/* if top most bit was at word break, go to next word */
if (!mask)
{
i--;
mask = BN_TBIT;
}
for (; i >= 0; i--)
{
word = scalar->d[i];
while (mask)
{
BN_consttime_swap(word & mask, x1, x2, group->field.top);
BN_consttime_swap(word & mask, z1, z2, group->field.top);
if (!gf2m_Madd(group, &point->X, x2, z2, x1, z1, ctx)) goto err;
if (!gf2m_Mdouble(group, x1, z1, ctx)) goto err;
BN_consttime_swap(word & mask, x1, x2, group->field.top);
BN_consttime_swap(word & mask, z1, z2, group->field.top);
mask >>= 1;
}
mask = BN_TBIT;
}
/* convert out of "projective" coordinates */
i = gf2m_Mxy(group, &point->X, &point->Y, x1, z1, x2, z2, ctx);
if (i == 0) goto err;
else if (i == 1)
{
if (!EC_POINT_set_to_infinity(group, r)) goto err;
}
else
{
if (!BN_one(&r->Z)) goto err;
r->Z_is_one = 1;
}
/* GF(2^m) field elements should always have BIGNUM::neg = 0 */
BN_set_negative(&r->X, 0);
BN_set_negative(&r->Y, 0);
ret = 1;
err:
BN_CTX_end(ctx);
return ret;
}
int ec_GFp_simple_group_check_discriminant(const EC_GROUP *group, BN_CTX *ctx)
{
int ret = 0;
BIGNUM *a, *b, *order, *tmp_1, *tmp_2;
const BIGNUM *p = &group->field;
BN_CTX *new_ctx = NULL;
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL) {
ECerr(EC_F_EC_GFP_SIMPLE_GROUP_CHECK_DISCRIMINANT,
ERR_R_MALLOC_FAILURE);
goto err;
}
}
BN_CTX_start(ctx);
a = BN_CTX_get(ctx);
b = BN_CTX_get(ctx);
tmp_1 = BN_CTX_get(ctx);
tmp_2 = BN_CTX_get(ctx);
order = BN_CTX_get(ctx);
if (order == NULL)
goto err;
if (group->meth->field_decode) {
if (!group->meth->field_decode(group, a, &group->a, ctx))
goto err;
if (!group->meth->field_decode(group, b, &group->b, ctx))
goto err;
} else {
if (!BN_copy(a, &group->a))
goto err;
if (!BN_copy(b, &group->b))
goto err;
}
/*-
* check the discriminant:
* y^2 = x^3 + a*x + b is an elliptic curve <=> 4*a^3 + 27*b^2 != 0 (mod p)
* 0 =< a, b < p
*/
if (BN_is_zero(a)) {
if (BN_is_zero(b))
goto err;
} else if (!BN_is_zero(b)) {
if (!BN_mod_sqr(tmp_1, a, p, ctx))
goto err;
if (!BN_mod_mul(tmp_2, tmp_1, a, p, ctx))
goto err;
if (!BN_lshift(tmp_1, tmp_2, 2))
goto err;
/* tmp_1 = 4*a^3 */
if (!BN_mod_sqr(tmp_2, b, p, ctx))
goto err;
if (!BN_mul_word(tmp_2, 27))
goto err;
/* tmp_2 = 27*b^2 */
if (!BN_mod_add(a, tmp_1, tmp_2, p, ctx))
goto err;
if (BN_is_zero(a))
goto err;
}
ret = 1;
err:
if (ctx != NULL)
BN_CTX_end(ctx);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
return ret;
}
/*
* Converts an octet string representation to an EC_POINT. Note that the
* simple implementation only uses affine coordinates.
*/
int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point,
const unsigned char *buf, size_t len,
BN_CTX *ctx)
{
point_conversion_form_t form;
int y_bit;
BN_CTX *new_ctx = NULL;
BIGNUM *x, *y, *yxi;
size_t field_len, enc_len;
int ret = 0;
if (len == 0) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_BUFFER_TOO_SMALL);
return 0;
}
form = buf[0];
y_bit = form & 1;
form = form & ~1U;
if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED)
&& (form != POINT_CONVERSION_UNCOMPRESSED)
&& (form != POINT_CONVERSION_HYBRID)) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
return 0;
}
if ((form == 0 || form == POINT_CONVERSION_UNCOMPRESSED) && y_bit) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
return 0;
}
if (form == 0) {
if (len != 1) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
return 0;
}
return EC_POINT_set_to_infinity(group, point);
}
field_len = (EC_GROUP_get_degree(group) + 7) / 8;
enc_len =
(form ==
POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len;
if (len != enc_len) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
return 0;
}
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
BN_CTX_start(ctx);
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
yxi = BN_CTX_get(ctx);
if (yxi == NULL)
goto err;
if (!BN_bin2bn(buf + 1, field_len, x))
goto err;
if (BN_ucmp(x, group->field) >= 0) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
goto err;
}
if (form == POINT_CONVERSION_COMPRESSED) {
if (!EC_POINT_set_compressed_coordinates_GF2m
(group, point, x, y_bit, ctx))
goto err;
} else {
if (!BN_bin2bn(buf + 1 + field_len, field_len, y))
goto err;
if (BN_ucmp(y, group->field) >= 0) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
goto err;
}
if (form == POINT_CONVERSION_HYBRID) {
if (!group->meth->field_div(group, yxi, y, x, ctx))
goto err;
if (y_bit != BN_is_odd(yxi)) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING);
goto err;
}
}
if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx))
goto err;
}
/* test required by X9.62 */
if (EC_POINT_is_on_curve(group, point, ctx) <= 0) {
ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_POINT_IS_NOT_ON_CURVE);
goto err;
}
ret = 1;
err:
BN_CTX_end(ctx);
BN_CTX_free(new_ctx);
return ret;
}
int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group,
const EC_POINT *point,
BIGNUM *x, BIGNUM *y,
BN_CTX *ctx)
{
BN_CTX *new_ctx = NULL;
BIGNUM *Z, *Z_1, *Z_2, *Z_3;
const BIGNUM *Z_;
int ret = 0;
if (EC_POINT_is_at_infinity(group, point)) {
ECerr(EC_F_EC_GFP_SIMPLE_POINT_GET_AFFINE_COORDINATES,
EC_R_POINT_AT_INFINITY);
return 0;
}
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
BN_CTX_start(ctx);
Z = BN_CTX_get(ctx);
Z_1 = BN_CTX_get(ctx);
Z_2 = BN_CTX_get(ctx);
Z_3 = BN_CTX_get(ctx);
if (Z_3 == NULL)
goto err;
/* transform (X, Y, Z) into (x, y) := (X/Z^2, Y/Z^3) */
if (group->meth->field_decode) {
if (!group->meth->field_decode(group, Z, &point->Z, ctx))
goto err;
Z_ = Z;
} else {
Z_ = &point->Z;
}
if (BN_is_one(Z_)) {
if (group->meth->field_decode) {
if (x != NULL) {
if (!group->meth->field_decode(group, x, &point->X, ctx))
goto err;
}
if (y != NULL) {
if (!group->meth->field_decode(group, y, &point->Y, ctx))
goto err;
}
} else {
if (x != NULL) {
if (!BN_copy(x, &point->X))
goto err;
}
if (y != NULL) {
if (!BN_copy(y, &point->Y))
goto err;
}
}
} else {
if (!BN_mod_inverse(Z_1, Z_, &group->field, ctx)) {
ECerr(EC_F_EC_GFP_SIMPLE_POINT_GET_AFFINE_COORDINATES,
ERR_R_BN_LIB);
goto err;
}
if (group->meth->field_encode == 0) {
/* field_sqr works on standard representation */
if (!group->meth->field_sqr(group, Z_2, Z_1, ctx))
goto err;
} else {
if (!BN_mod_sqr(Z_2, Z_1, &group->field, ctx))
goto err;
}
if (x != NULL) {
/*
* in the Montgomery case, field_mul will cancel out Montgomery
* factor in X:
*/
if (!group->meth->field_mul(group, x, &point->X, Z_2, ctx))
goto err;
}
if (y != NULL) {
if (group->meth->field_encode == 0) {
/*
* field_mul works on standard representation
*/
if (!group->meth->field_mul(group, Z_3, Z_2, Z_1, ctx))
goto err;
} else {
if (!BN_mod_mul(Z_3, Z_2, Z_1, &group->field, ctx))
goto err;
}
/*
* in the Montgomery case, field_mul will cancel out Montgomery
* factor in Y:
*/
if (!group->meth->field_mul(group, y, &point->Y, Z_3, ctx))
goto err;
}
}
ret = 1;
err:
BN_CTX_end(ctx);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
return ret;
}
int EC_GROUP_copy(EC_GROUP *dest, const EC_GROUP *src)
{
if (dest->meth->group_copy == 0) {
ECerr(EC_F_EC_GROUP_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return 0;
}
if (dest->meth != src->meth) {
ECerr(EC_F_EC_GROUP_COPY, EC_R_INCOMPATIBLE_OBJECTS);
return 0;
}
if (dest == src)
return 1;
dest->curve_name = src->curve_name;
/* Copy precomputed */
dest->pre_comp_type = src->pre_comp_type;
switch (src->pre_comp_type) {
case PCT_none:
dest->pre_comp.ec = NULL;
break;
case PCT_nistz256:
#ifdef ECP_NISTZ256_ASM
dest->pre_comp.nistz256 = EC_nistz256_pre_comp_dup(src->pre_comp.nistz256);
#endif
break;
#ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
case PCT_nistp224:
dest->pre_comp.nistp224 = EC_nistp224_pre_comp_dup(src->pre_comp.nistp224);
break;
case PCT_nistp256:
dest->pre_comp.nistp256 = EC_nistp256_pre_comp_dup(src->pre_comp.nistp256);
break;
case PCT_nistp521:
dest->pre_comp.nistp521 = EC_nistp521_pre_comp_dup(src->pre_comp.nistp521);
break;
#else
case PCT_nistp224:
case PCT_nistp256:
case PCT_nistp521:
break;
#endif
case PCT_ec:
dest->pre_comp.ec = EC_ec_pre_comp_dup(src->pre_comp.ec);
break;
}
if (src->mont_data != NULL) {
if (dest->mont_data == NULL) {
dest->mont_data = BN_MONT_CTX_new();
if (dest->mont_data == NULL)
return 0;
}
if (!BN_MONT_CTX_copy(dest->mont_data, src->mont_data))
return 0;
} else {
/* src->generator == NULL */
BN_MONT_CTX_free(dest->mont_data);
dest->mont_data = NULL;
}
if (src->generator != NULL) {
if (dest->generator == NULL) {
dest->generator = EC_POINT_new(dest);
if (dest->generator == NULL)
return 0;
}
if (!EC_POINT_copy(dest->generator, src->generator))
return 0;
} else {
/* src->generator == NULL */
EC_POINT_clear_free(dest->generator);
dest->generator = NULL;
}
if ((src->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
if (!BN_copy(dest->order, src->order))
return 0;
if (!BN_copy(dest->cofactor, src->cofactor))
return 0;
}
dest->asn1_flag = src->asn1_flag;
dest->asn1_form = src->asn1_form;
if (src->seed) {
OPENSSL_free(dest->seed);
if ((dest->seed = OPENSSL_malloc(src->seed_len)) == NULL) {
ECerr(EC_F_EC_GROUP_COPY, ERR_R_MALLOC_FAILURE);
return 0;
}
if (!memcpy(dest->seed, src->seed, src->seed_len))
return 0;
dest->seed_len = src->seed_len;
} else {
OPENSSL_free(dest->seed);
dest->seed = NULL;
dest->seed_len = 0;
}
return dest->meth->group_copy(dest, src);
}
int ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *group,
EC_POINT *point,
const BIGNUM *x_, int y_bit,
BN_CTX *ctx)
{
BN_CTX *new_ctx = NULL;
BIGNUM *tmp1, *tmp2, *x, *y;
int ret = 0;
/* clear error queue */
ERR_clear_error();
if (ctx == NULL) {
ctx = new_ctx = BN_CTX_new();
if (ctx == NULL)
return 0;
}
y_bit = (y_bit != 0);
BN_CTX_start(ctx);
tmp1 = BN_CTX_get(ctx);
tmp2 = BN_CTX_get(ctx);
x = BN_CTX_get(ctx);
y = BN_CTX_get(ctx);
if (y == NULL)
goto err;
/*-
* Recover y. We have a Weierstrass equation
* y^2 = x^3 + a*x + b,
* so y is one of the square roots of x^3 + a*x + b.
*/
/* tmp1 := x^3 */
if (!BN_nnmod(x, x_, &group->field, ctx))
goto err;
if (group->meth->field_decode == 0) {
/* field_{sqr,mul} work on standard representation */
if (!group->meth->field_sqr(group, tmp2, x_, ctx))
goto err;
if (!group->meth->field_mul(group, tmp1, tmp2, x_, ctx))
goto err;
} else {
if (!BN_mod_sqr(tmp2, x_, &group->field, ctx))
goto err;
if (!BN_mod_mul(tmp1, tmp2, x_, &group->field, ctx))
goto err;
}
/* tmp1 := tmp1 + a*x */
if (group->a_is_minus3) {
if (!BN_mod_lshift1_quick(tmp2, x, &group->field))
goto err;
if (!BN_mod_add_quick(tmp2, tmp2, x, &group->field))
goto err;
if (!BN_mod_sub_quick(tmp1, tmp1, tmp2, &group->field))
goto err;
} else {
if (group->meth->field_decode) {
if (!group->meth->field_decode(group, tmp2, &group->a, ctx))
goto err;
if (!BN_mod_mul(tmp2, tmp2, x, &group->field, ctx))
goto err;
} else {
/* field_mul works on standard representation */
if (!group->meth->field_mul(group, tmp2, &group->a, x, ctx))
goto err;
}
if (!BN_mod_add_quick(tmp1, tmp1, tmp2, &group->field))
goto err;
}
/* tmp1 := tmp1 + b */
if (group->meth->field_decode) {
if (!group->meth->field_decode(group, tmp2, &group->b, ctx))
goto err;
if (!BN_mod_add_quick(tmp1, tmp1, tmp2, &group->field))
goto err;
} else {
if (!BN_mod_add_quick(tmp1, tmp1, &group->b, &group->field))
goto err;
}
if (!BN_mod_sqrt(y, tmp1, &group->field, ctx)) {
unsigned long err = ERR_peek_last_error();
if (ERR_GET_LIB(err) == ERR_LIB_BN
&& ERR_GET_REASON(err) == BN_R_NOT_A_SQUARE) {
ERR_clear_error();
ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES,
EC_R_INVALID_COMPRESSED_POINT);
} else
ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES,
ERR_R_BN_LIB);
goto err;
}
if (y_bit != BN_is_odd(y)) {
if (BN_is_zero(y)) {
int kron;
kron = BN_kronecker(x, &group->field, ctx);
if (kron == -2)
goto err;
if (kron == 1)
ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES,
EC_R_INVALID_COMPRESSION_BIT);
else
/*
* BN_mod_sqrt() should have cought this error (not a square)
*/
ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES,
EC_R_INVALID_COMPRESSED_POINT);
goto err;
}
if (!BN_usub(y, &group->field, y))
goto err;
}
if (y_bit != BN_is_odd(y)) {
ECerr(EC_F_EC_GFP_SIMPLE_SET_COMPRESSED_COORDINATES,
ERR_R_INTERNAL_ERROR);
goto err;
}
if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx))
goto err;
ret = 1;
err:
BN_CTX_end(ctx);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
return ret;
}
int EC_KEY_generate_key(EC_KEY *eckey)
{
int ok = 0;
BN_CTX *ctx = NULL;
BIGNUM *priv_key = NULL, *order = NULL;
EC_POINT *pub_key = NULL;
#ifdef OPENSSL_FIPS
if (FIPS_mode())
return FIPS_ec_key_generate_key(eckey);
#endif
if (!eckey || !eckey->group)
{
ECerr(EC_F_EC_KEY_GENERATE_KEY, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if ((order = BN_new()) == NULL) goto err;
if ((ctx = BN_CTX_new()) == NULL) goto err;
if (eckey->priv_key == NULL)
{
priv_key = BN_new();
if (priv_key == NULL)
goto err;
}
else
priv_key = eckey->priv_key;
if (!EC_GROUP_get_order(eckey->group, order, ctx))
goto err;
do
if (!BN_rand_range(priv_key, order))
goto err;
while (BN_is_zero(priv_key));
if (eckey->pub_key == NULL)
{
pub_key = EC_POINT_new(eckey->group);
if (pub_key == NULL)
goto err;
}
else
pub_key = eckey->pub_key;
if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx))
goto err;
eckey->priv_key = priv_key;
eckey->pub_key = pub_key;
ok=1;
err:
if (order)
BN_free(order);
if (pub_key != NULL && eckey->pub_key == NULL)
EC_POINT_free(pub_key);
if (priv_key != NULL && eckey->priv_key == NULL)
BN_free(priv_key);
if (ctx != NULL)
BN_CTX_free(ctx);
return(ok);
}
static int ecdh_cms_set_shared_info(EVP_PKEY_CTX *pctx, CMS_RecipientInfo *ri)
{
int rv = 0;
X509_ALGOR *alg, *kekalg = NULL;
ASN1_OCTET_STRING *ukm;
const unsigned char *p;
unsigned char *der = NULL;
int plen, keylen;
const EVP_CIPHER *kekcipher;
EVP_CIPHER_CTX *kekctx;
if (!CMS_RecipientInfo_kari_get0_alg(ri, &alg, &ukm))
return 0;
if (!ecdh_cms_set_kdf_param(pctx, OBJ_obj2nid(alg->algorithm)))
{
ECerr(EC_F_ECDH_CMS_SET_SHARED_INFO, EC_R_KDF_PARAMETER_ERROR);
return 0;
}
if (alg->parameter->type != V_ASN1_SEQUENCE)
return 0;
p = alg->parameter->value.sequence->data;
plen = alg->parameter->value.sequence->length;
kekalg = d2i_X509_ALGOR(NULL, &p, plen);
if (!kekalg)
goto err;
kekctx = CMS_RecipientInfo_kari_get0_ctx(ri);
if (!kekctx)
goto err;
kekcipher = EVP_get_cipherbyobj(kekalg->algorithm);
if (!kekcipher || EVP_CIPHER_mode(kekcipher) != EVP_CIPH_WRAP_MODE)
goto err;
if (!EVP_EncryptInit_ex(kekctx, kekcipher, NULL, NULL, NULL))
goto err;
if (EVP_CIPHER_asn1_to_param(kekctx, kekalg->parameter) <= 0)
goto err;
keylen = EVP_CIPHER_CTX_key_length(kekctx);
if (EVP_PKEY_CTX_set_ecdh_kdf_outlen(pctx, keylen) <= 0)
goto err;
plen = CMS_SharedInfo_encode(&der, kekalg, ukm, keylen);
if (!plen)
goto err;
if (EVP_PKEY_CTX_set0_ecdh_kdf_ukm(pctx, der, plen) <= 0)
goto err;
der = NULL;
rv = 1;
err:
if (kekalg)
X509_ALGOR_free(kekalg);
if (der)
OPENSSL_free(der);
return rv;
}
int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, BIGNUM *y)
{
BN_CTX *ctx = NULL;
BIGNUM *tx, *ty;
EC_POINT *point = NULL;
int ok = 0, tmp_nid, is_char_two = 0;
if (!key || !key->group || !x || !y)
{
ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES,
ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
ctx = BN_CTX_new();
if (!ctx)
goto err;
point = EC_POINT_new(key->group);
if (!point)
goto err;
tmp_nid = EC_METHOD_get_field_type(EC_GROUP_method_of(key->group));
if (tmp_nid == NID_X9_62_characteristic_two_field)
is_char_two = 1;
tx = BN_CTX_get(ctx);
ty = BN_CTX_get(ctx);
#ifndef OPENSSL_NO_EC2M
if (is_char_two)
{
if (!EC_POINT_set_affine_coordinates_GF2m(key->group, point,
x, y, ctx))
goto err;
if (!EC_POINT_get_affine_coordinates_GF2m(key->group, point,
tx, ty, ctx))
goto err;
}
else
#endif
{
if (!EC_POINT_set_affine_coordinates_GFp(key->group, point,
x, y, ctx))
goto err;
if (!EC_POINT_get_affine_coordinates_GFp(key->group, point,
tx, ty, ctx))
goto err;
}
/* Check if retrieved coordinates match originals: if not values
* are out of range.
*/
if (BN_cmp(x, tx) || BN_cmp(y, ty))
{
ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES,
EC_R_COORDINATES_OUT_OF_RANGE);
goto err;
}
if (!EC_KEY_set_public_key(key, point))
goto err;
if (EC_KEY_check_key(key) == 0)
goto err;
ok = 1;
err:
if (ctx)
BN_CTX_free(ctx);
if (point)
EC_POINT_free(point);
return ok;
}
ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
const BIGNUM *in_kinv, const BIGNUM *in_r,
EC_KEY *eckey)
{
int ok = 0, i;
BIGNUM *kinv = NULL, *s, *m = NULL, *tmp = NULL;
const BIGNUM *order, *ckinv;
BN_CTX *ctx = NULL;
const EC_GROUP *group;
ECDSA_SIG *ret;
const BIGNUM *priv_key;
group = EC_KEY_get0_group(eckey);
priv_key = EC_KEY_get0_private_key(eckey);
if (group == NULL || priv_key == NULL) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_PASSED_NULL_PARAMETER);
return NULL;
}
if (!EC_KEY_can_sign(eckey)) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
return NULL;
}
ret = ECDSA_SIG_new();
if (ret == NULL) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_MALLOC_FAILURE);
return NULL;
}
ret->r = BN_new();
ret->s = BN_new();
if (ret->r == NULL || ret->s == NULL) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_MALLOC_FAILURE);
goto err;
}
s = ret->s;
if ((ctx = BN_CTX_new()) == NULL ||
(tmp = BN_new()) == NULL || (m = BN_new()) == NULL) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_MALLOC_FAILURE);
goto err;
}
order = EC_GROUP_get0_order(group);
if (order == NULL) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_EC_LIB);
goto err;
}
i = BN_num_bits(order);
/*
* Need to truncate digest if it is too long: first truncate whole bytes.
*/
if (8 * dgst_len > i)
dgst_len = (i + 7) / 8;
if (!BN_bin2bn(dgst, dgst_len, m)) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
goto err;
}
/* If still too long truncate remaining bits with a shift */
if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
goto err;
}
do {
if (in_kinv == NULL || in_r == NULL) {
if (!ecdsa_sign_setup(eckey, ctx, &kinv, &ret->r, dgst, dgst_len)) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_ECDSA_LIB);
goto err;
}
ckinv = kinv;
} else {
ckinv = in_kinv;
if (BN_copy(ret->r, in_r) == NULL) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_MALLOC_FAILURE);
goto err;
}
}
if (!BN_mod_mul(tmp, priv_key, ret->r, order, ctx)) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
goto err;
}
if (!BN_mod_add_quick(s, tmp, m, order)) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
goto err;
}
if (!BN_mod_mul(s, s, ckinv, order, ctx)) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
goto err;
}
if (BN_is_zero(s)) {
/*
* if kinv and r have been supplied by the caller, don't
* generate new kinv and r values
*/
if (in_kinv != NULL && in_r != NULL) {
ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, EC_R_NEED_NEW_SETUP_VALUES);
goto err;
}
} else
/* s != 0 => we have a valid signature */
break;
}
while (1);
ok = 1;
err:
if (!ok) {
ECDSA_SIG_free(ret);
ret = NULL;
}
BN_CTX_free(ctx);
BN_clear_free(m);
BN_clear_free(tmp);
BN_clear_free(kinv);
return ret;
}