diff options
| author | NIIBE Yutaka <gniibe@fsij.org> | 2021-02-02 10:16:13 +0900 |
|---|---|---|
| committer | Werner Koch <wk@gnupg.org> | 2021-02-04 12:44:07 +0100 |
| commit | 1d312bc65846916c120506ae237235c8fbbea897 (patch) | |
| tree | 60cd489de0456a9f5939956e1c7604e41aea4407 | |
| parent | 16e855d49ca26432218a7be7416f193de1c31878 (diff) | |
| download | libgcrypt-1d312bc65846916c120506ae237235c8fbbea897.tar.gz | |
ecc: Add checking key for ECDSA.
* cipher/ecc-ecdsa.c (_gcry_ecc_ecdsa_verify): Validate public key.
* cipher/ecc-gost.c (_gcry_ecc_gost_verify): Likewise.
--
GnuPG-bug-id: 5282
Reported-by: Guido Vranken <guidovranken@gmail.com>
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
Backported-from-master: 598d0f3e0294a487e01b88cc714a8cd0a47329bb
| -rw-r--r-- | cipher/ecc-ecdsa.c | 6 | ||||
| -rw-r--r-- | cipher/ecc-gost.c | 6 |
2 files changed, 12 insertions, 0 deletions
diff --git a/cipher/ecc-ecdsa.c b/cipher/ecc-ecdsa.c index 56846f44..82b609e5 100644 --- a/cipher/ecc-ecdsa.c +++ b/cipher/ecc-ecdsa.c @@ -199,6 +199,12 @@ _gcry_ecc_ecdsa_verify (gcry_mpi_t input, ECC_public_key *pkey, ctx = _gcry_mpi_ec_p_internal_new (pkey->E.model, pkey->E.dialect, 0, pkey->E.p, pkey->E.a, pkey->E.b); + if (!_gcry_mpi_ec_curve_point (&pkey->Q, ctx)) + { + err = GPG_ERR_BROKEN_PUBKEY; + goto leave; + } + /* h = s^(-1) (mod n) */ mpi_invm (h, s, pkey->E.n); /* h1 = hash * s^(-1) (mod n) */ diff --git a/cipher/ecc-gost.c b/cipher/ecc-gost.c index 0362a6c7..a68750fa 100644 --- a/cipher/ecc-gost.c +++ b/cipher/ecc-gost.c @@ -168,6 +168,12 @@ _gcry_ecc_gost_verify (gcry_mpi_t input, ECC_public_key *pkey, ctx = _gcry_mpi_ec_p_internal_new (pkey->E.model, pkey->E.dialect, 0, pkey->E.p, pkey->E.a, pkey->E.b); + if (!_gcry_mpi_ec_curve_point (&pkey->Q, ctx)) + { + err = GPG_ERR_BROKEN_PUBKEY; + goto leave; + } + mpi_mod (e, input, pkey->E.n); /* e = hash mod n */ if (!mpi_cmp_ui (e, 0)) mpi_set_ui (e, 1); |