commit 0d9873ac0daa82fa9d43c1eb7e93ec75758f2063 Author: George Kadianakis desnacked@riseup.net Date: Wed Jun 28 14:10:10 2017 +0300
ed25519: Check retval of unpack_negative_vartime in donna. --- src/common/crypto_ed25519.c | 10 ++++++---- src/ext/ed25519/donna/ed25519_tor.c | 4 +++- 2 files changed, 9 insertions(+), 5 deletions(-)
diff --git a/src/common/crypto_ed25519.c b/src/common/crypto_ed25519.c index 1a6d19b..d61549b 100644 --- a/src/common/crypto_ed25519.c +++ b/src/common/crypto_ed25519.c @@ -497,7 +497,8 @@ ed25519_public_key_from_curve25519_public_key(ed25519_public_key_t *pubkey, * service descriptors are encrypted with a key derived from the service's * long-term public key, and then signed with (and stored at a position * indexed by) a short-term key derived by blinding the long-term keys. - */ + * + * Return 0 if blinding was successful, else return -1. */ int ed25519_keypair_blind(ed25519_keypair_t *out, const ed25519_keypair_t *inp, @@ -508,7 +509,9 @@ ed25519_keypair_blind(ed25519_keypair_t *out, get_ed_impl()->blind_secret_key(out->seckey.seckey, inp->seckey.seckey, param);
- ed25519_public_blind(&pubkey_check, &inp->pubkey, param); + if (ed25519_public_blind(&pubkey_check, &inp->pubkey, param) < 0) { + return -1; + } ed25519_public_key_generate(&out->pubkey, &out->seckey);
tor_assert(fast_memeq(pubkey_check.pubkey, out->pubkey.pubkey, 32)); @@ -528,8 +531,7 @@ ed25519_public_blind(ed25519_public_key_t *out, const ed25519_public_key_t *inp, const uint8_t *param) { - get_ed_impl()->blind_public_key(out->pubkey, inp->pubkey, param); - return 0; + return get_ed_impl()->blind_public_key(out->pubkey, inp->pubkey, param); }
/** diff --git a/src/ext/ed25519/donna/ed25519_tor.c b/src/ext/ed25519/donna/ed25519_tor.c index bd11027..6bc2267 100644 --- a/src/ext/ed25519/donna/ed25519_tor.c +++ b/src/ext/ed25519/donna/ed25519_tor.c @@ -304,7 +304,9 @@ ed25519_donna_blind_public_key(unsigned char *out, const unsigned char *inp, /* No "ge25519_unpack", negate the public key. */ memcpy(pkcopy, inp, 32); pkcopy[31] ^= (1<<7); - ge25519_unpack_negative_vartime(&A, pkcopy); + if (!ge25519_unpack_negative_vartime(&A, pkcopy)) { + return -1; + }
/* A' = [tweak] * A + [0] * basepoint. */ ge25519_double_scalarmult_vartime(&Aprime, &A, t, zero);