Skip to content

Commit

Permalink
EC_POINT_is_on_curve does not return a boolean
Browse files Browse the repository at this point in the history 
The function EC_POINT_is_on_curve does not return a boolean value.
It returns 1 if the point is on the curve, 0 if it is not, and -1
on error. Many usages within OpenSSL were incorrectly using this
function and therefore not correctly handling error conditions.

With thanks to the Open Crypto Audit Project for reporting this issue.

Reviewed-by: Kurt Roeckx <[email protected]>
  • Loading branch information
@mattcaswell
mattcaswell committed Jun 10, 2015
1 parent b8b12aa commit 68886be
Show file tree
Hide file tree
Showing 6 changed files with 23 additions and 16 deletions.
2 changes: 1 addition & 1 deletion crypto/ec/ec2_oct.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -384,7 +384,7 @@ int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point,
}

/* test required by X9.62 */
if (!EC_POINT_is_on_curve(group, point, ctx)) {
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;
}
Expand Down
2 changes: 1 addition & 1 deletion crypto/ec/ec_check.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -85,7 +85,7 @@ int EC_GROUP_check(const EC_GROUP *group, BN_CTX *ctx)
ECerr(EC_F_EC_GROUP_CHECK, EC_R_UNDEFINED_GENERATOR);
goto err;
}
if (!EC_POINT_is_on_curve(group, group->generator, ctx)) {
if (EC_POINT_is_on_curve(group, group->generator, ctx) <= 0) {
ECerr(EC_F_EC_GROUP_CHECK, EC_R_POINT_IS_NOT_ON_CURVE);
goto err;
}
Expand Down
2 changes: 1 addition & 1 deletion crypto/ec/ec_key.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -296,7 +296,7 @@ int EC_KEY_check_key(const EC_KEY *eckey)
goto err;

/* testing whether the pub_key is on the elliptic curve */
if (!EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx)) {
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;
}
Expand Down
7 changes: 7 additions & 0 deletions crypto/ec/ec_lib.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -949,6 +949,13 @@ int EC_POINT_is_at_infinity(const EC_GROUP *group, const EC_POINT *point)
return group->meth->is_at_infinity(group, point);
}

/*
* Check whether an EC_POINT is on the curve or not. Note that the return
* value for this function should NOT be treated as a boolean. Return values:
* 1: The point is on the curve
* 0: The point is not on the curve
* -1: An error occurred
*/
int EC_POINT_is_on_curve(const EC_GROUP *group, const EC_POINT *point,
BN_CTX *ctx)
{
Expand Down
2 changes: 1 addition & 1 deletion crypto/ec/ecp_oct.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -410,7 +410,7 @@ int ec_GFp_simple_oct2point(const EC_GROUP *group, EC_POINT *point,
}

/* test required by X9.62 */
if (!EC_POINT_is_on_curve(group, point, ctx)) {
if (EC_POINT_is_on_curve(group, point, ctx) <= 0) {
ECerr(EC_F_EC_GFP_SIMPLE_OCT2POINT, EC_R_POINT_IS_NOT_ON_CURVE);
goto err;
}
Expand Down
24 changes: 12 additions & 12 deletions test/ectest.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -319,7 +319,7 @@ static void prime_field_tests(void)
ABORT;
if (!EC_POINT_set_compressed_coordinates_GFp(group, Q, x, 1, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, Q, ctx)) {
if (EC_POINT_is_on_curve(group, Q, ctx) <= 0) {
if (!EC_POINT_get_affine_coordinates_GFp(group, Q, x, y, ctx))
ABORT;
fprintf(stderr, "Point is not on curve: x = 0x");
Expand Down Expand Up @@ -439,7 +439,7 @@ static void prime_field_tests(void)
ABORT;
if (!EC_POINT_set_affine_coordinates_GFp(group, P, x, y, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, P, ctx))
if (EC_POINT_is_on_curve(group, P, ctx) <= 0)
ABORT;
if (!BN_hex2bn(&z, "0100000000000000000001F4C8F927AED3CA752257"))
ABORT;
Expand Down Expand Up @@ -488,7 +488,7 @@ static void prime_field_tests(void)
ABORT;
if (!EC_POINT_set_compressed_coordinates_GFp(group, P, x, 1, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, P, ctx))
if (EC_POINT_is_on_curve(group, P, ctx) <= 0)
ABORT;
if (!BN_hex2bn(&z, "FFFFFFFFFFFFFFFFFFFFFFFF99DEF836146BC9B1B4D22831"))
ABORT;
Expand Down Expand Up @@ -541,7 +541,7 @@ static void prime_field_tests(void)
ABORT;
if (!EC_POINT_set_compressed_coordinates_GFp(group, P, x, 0, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, P, ctx))
if (EC_POINT_is_on_curve(group, P, ctx) <= 0)
ABORT;
if (!BN_hex2bn
(&z, "FFFFFFFFFFFFFFFFFFFFFFFFFFFF16A2E0B8F03E13DD29455C5C2A3D"))
Expand Down Expand Up @@ -600,7 +600,7 @@ static void prime_field_tests(void)
ABORT;
if (!EC_POINT_set_compressed_coordinates_GFp(group, P, x, 1, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, P, ctx))
if (EC_POINT_is_on_curve(group, P, ctx) <= 0)
ABORT;
if (!BN_hex2bn(&z, "FFFFFFFF00000000FFFFFFFFFFFFFFFFBCE6FAADA7179E"
"84F3B9CAC2FC632551"))
Expand Down Expand Up @@ -656,7 +656,7 @@ static void prime_field_tests(void)
ABORT;
if (!EC_POINT_set_compressed_coordinates_GFp(group, P, x, 1, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, P, ctx))
if (EC_POINT_is_on_curve(group, P, ctx) <= 0)
ABORT;
if (!BN_hex2bn(&z, "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
"FFC7634D81F4372DDF581A0DB248B0A77AECEC196ACCC52973"))
Expand Down Expand Up @@ -715,7 +715,7 @@ static void prime_field_tests(void)
ABORT;
if (!EC_POINT_set_compressed_coordinates_GFp(group, P, x, 0, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, P, ctx))
if (EC_POINT_is_on_curve(group, P, ctx) <= 0)
ABORT;
if (!BN_hex2bn(&z, "1FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
"FFFFFFFFFFFFFFFFFFFFA51868783BF2F966B7FCC0148F709A5D03BB5"
Expand Down Expand Up @@ -759,7 +759,7 @@ static void prime_field_tests(void)
ABORT;
if (!EC_POINT_dbl(group, P, P, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, P, ctx))
if (EC_POINT_is_on_curve(group, P, ctx) <= 0)
ABORT;
if (!EC_POINT_invert(group, Q, ctx))
ABORT; /* P = -2Q */
Expand Down Expand Up @@ -877,7 +877,7 @@ static void prime_field_tests(void)
# define CHAR2_CURVE_TEST_INTERNAL(_name, _p, _a, _b, _x, _y, _y_bit, _order, _cof, _degree, _variable) \
if (!BN_hex2bn(&x, _x)) ABORT; \
if (!EC_POINT_set_compressed_coordinates_GF2m(group, P, x, _y_bit, ctx)) ABORT; \
if (!EC_POINT_is_on_curve(group, P, ctx)) ABORT; \
if (EC_POINT_is_on_curve(group, P, ctx) <= 0) ABORT; \
if (!BN_hex2bn(&z, _order)) ABORT; \
if (!BN_hex2bn(&cof, _cof)) ABORT; \
if (!EC_GROUP_set_generator(group, P, z, cof)) ABORT; \
Expand All @@ -895,7 +895,7 @@ static void prime_field_tests(void)
if (!BN_hex2bn(&x, _x)) ABORT; \
if (!BN_hex2bn(&y, _y)) ABORT; \
if (!EC_POINT_set_affine_coordinates_GF2m(group, P, x, y, ctx)) ABORT; \
if (!EC_POINT_is_on_curve(group, P, ctx)) ABORT; \
if (EC_POINT_is_on_curve(group, P, ctx) <= 0) ABORT; \
if (!BN_hex2bn(&z, _order)) ABORT; \
if (!BN_hex2bn(&cof, _cof)) ABORT; \
if (!EC_GROUP_set_generator(group, P, z, cof)) ABORT; \
Expand Down Expand Up @@ -1024,7 +1024,7 @@ static void char2_field_tests(void)
if (!EC_POINT_set_affine_coordinates_GF2m(group, Q, x, y, ctx))
ABORT;
# endif
if (!EC_POINT_is_on_curve(group, Q, ctx)) {
if (EC_POINT_is_on_curve(group, Q, ctx) <= 0) {
/* Change test based on whether binary point compression is enabled or not. */
# ifdef OPENSSL_EC_BIN_PT_COMP
if (!EC_POINT_get_affine_coordinates_GF2m(group, Q, x, y, ctx))
Expand Down Expand Up @@ -1245,7 +1245,7 @@ static void char2_field_tests(void)
ABORT;
if (!EC_POINT_dbl(group, P, P, ctx))
ABORT;
if (!EC_POINT_is_on_curve(group, P, ctx))
if (EC_POINT_is_on_curve(group, P, ctx) <= 0)
ABORT;
if (!EC_POINT_invert(group, Q, ctx))
ABORT; /* P = -2Q */
Expand Down

0 comments on commit 68886be

Please sign in to comment.