wbrawner/openssl
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Add a test for underflow in ecp_nistp521.c

Browse source 
The previous commit fixed an underflow that may occur in ecp_nistp521.c.
This commit adds a test for that condition. It is heavily based on an
original test harness by Billy Brumley.

Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/8405)
This commit is contained in:
Matt Caswell 2019-03-06 11:51:28 +00:00
parent 13fbce17fc
commit 6855b496b2
1 changed files with 69 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

69
test/ectest.c
View file

@ -1440,6 +1440,74 @@ err:
BN_CTX_free(ctx);
return r;
}
/*
* Tests a point known to cause an incorrect underflow in an old version of
* ecp_nist521.c
*/
static int underflow_test(void)
{
BN_CTX *ctx = NULL;
EC_GROUP *grp = NULL;
EC_POINT *P = NULL, *Q = NULL, *R = NULL;
BIGNUM *x1 = NULL, *y1 = NULL, *z1 = NULL, *x2 = NULL, *y2 = NULL;
BIGNUM *k = NULL;
int testresult = 0;
const char *x1str =
"1534f0077fffffe87e9adcfe000000000000000000003e05a21d2400002e031b1f4"
"b80000c6fafa4f3c1288798d624a247b5e2ffffffffffffffefe099241900004";
const char *p521m1 =
"1ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"
"fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe";
ctx = BN_CTX_new();
if (!TEST_ptr(ctx))
return 0;
BN_CTX_start(ctx);
x1 = BN_CTX_get(ctx);
y1 = BN_CTX_get(ctx);
z1 = BN_CTX_get(ctx);
x2 = BN_CTX_get(ctx);
y2 = BN_CTX_get(ctx);
k = BN_CTX_get(ctx);
if (!TEST_ptr(k))
goto err;
grp = EC_GROUP_new_by_curve_name(NID_secp521r1);
P = EC_POINT_new(grp);
Q = EC_POINT_new(grp);
R = EC_POINT_new(grp);
if (!TEST_ptr(grp) || !TEST_ptr(P) || !TEST_ptr(Q) || !TEST_ptr(R))
goto err;
if (!TEST_int_gt(BN_hex2bn(&x1, x1str), 0)
|| !TEST_int_gt(BN_hex2bn(&y1, p521m1), 0)
|| !TEST_int_gt(BN_hex2bn(&z1, p521m1), 0)
|| !TEST_int_gt(BN_hex2bn(&k, "02"), 0)
|| !TEST_true(EC_POINT_set_Jprojective_coordinates_GFp(grp, P, x1,
y1, z1, ctx))
|| !TEST_true(EC_POINT_mul(grp, Q, NULL, P, k, ctx))
|| !TEST_true(EC_POINT_get_affine_coordinates(grp, Q, x1, y1, ctx))
|| !TEST_true(EC_POINT_dbl(grp, R, P, ctx))
|| !TEST_true(EC_POINT_get_affine_coordinates(grp, R, x2, y2, ctx)))
goto err;
if (!TEST_int_eq(BN_cmp(x1, x2), 0)
|| !TEST_int_eq(BN_cmp(y1, y2), 0))
goto err;
testresult = 1;
err:
BN_CTX_end(ctx);
EC_POINT_free(P);
EC_POINT_free(Q);
EC_GROUP_free(grp);
BN_CTX_free(ctx);
return testresult;
}
# endif
static const unsigned char p521_named[] = {
@ -1547,6 +1615,7 @@ int setup_tests(void)
# endif
# ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
ADD_ALL_TESTS(nistp_single_test, OSSL_NELEM(nistp_tests_params));
ADD_TEST(underflow_test);
# endif
ADD_ALL_TESTS(internal_curve_test, crv_len);
ADD_ALL_TESTS(internal_curve_test_method, crv_len);