diff options
| author | Jason A. Donenfeld <Jason@zx2c4.com> | 2017-11-11 12:24:51 +0900 |
|---|---|---|
| committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2017-11-11 12:24:51 +0900 |
| commit | b94c2091ac92c8acbcc5338146da6fc5888f4e54 (patch) | |
| tree | 913b7166bdc97970420a1064d14ec1dae04cd866 /src | |
| parent | 74e08c0f671ebddda400ede1a5f00d23d33b6179 (diff) | |
curve25519: reject deriving from NULL private keys
These aren't actually valid 25519 points pre-normalization, and doing
this is required to make unsetting private keys based on all zeros.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Diffstat (limited to 'src')
| -rw-r--r-- | src/crypto/curve25519.c | 7 | ||||
| -rw-r--r-- | src/netlink.c | 16 |
2 files changed, 16 insertions, 7 deletions
diff --git a/src/crypto/curve25519.c b/src/crypto/curve25519.c index afc2a99..232c6d4 100644 --- a/src/crypto/curve25519.c +++ b/src/crypto/curve25519.c @@ -619,6 +619,10 @@ bool curve25519(u8 mypublic[CURVE25519_POINT_SIZE], const u8 secret[CURVE25519_P bool curve25519_generate_public(u8 pub[CURVE25519_POINT_SIZE], const u8 secret[CURVE25519_POINT_SIZE]) { static const u8 basepoint[CURVE25519_POINT_SIZE] __aligned(32) = { 9 }; + + if (unlikely(!crypto_memneq(secret, null_point, CURVE25519_POINT_SIZE))) + return false; + #ifdef CONFIG_X86_64 if (curve25519_use_avx && irq_fpu_usable()) { kernel_fpu_begin(); @@ -1676,6 +1680,9 @@ bool curve25519_generate_public(u8 pub[CURVE25519_POINT_SIZE], const u8 secret[C { static const u8 basepoint[CURVE25519_POINT_SIZE] __aligned(32) = { 9 }; + if (unlikely(!crypto_memneq(secret, null_point, CURVE25519_POINT_SIZE))) + return false; + return curve25519(pub, secret, basepoint); } #endif diff --git a/src/netlink.c b/src/netlink.c index ba9e41b..f2e724a 100644 --- a/src/netlink.c +++ b/src/netlink.c @@ -421,15 +421,17 @@ static int set_device(struct sk_buff *skb, struct genl_info *info) if (info->attrs[WGDEVICE_A_PRIVATE_KEY] && nla_len(info->attrs[WGDEVICE_A_PRIVATE_KEY]) == NOISE_PUBLIC_KEY_LEN) { struct wireguard_peer *peer, *temp; - u8 public_key[NOISE_PUBLIC_KEY_LEN] = { 0 }, *private_key = nla_data(info->attrs[WGDEVICE_A_PRIVATE_KEY]); - /* We remove before setting, to prevent race, which means doing two 25519-genpub ops. */ - __attribute((unused)) bool unused = curve25519_generate_public(public_key, private_key); + u8 public_key[NOISE_PUBLIC_KEY_LEN], *private_key = nla_data(info->attrs[WGDEVICE_A_PRIVATE_KEY]); - peer = pubkey_hashtable_lookup(&wg->peer_hashtable, public_key); - if (peer) { - peer_put(peer); - peer_remove(peer); + /* We remove before setting, to prevent race, which means doing two 25519-genpub ops. */ + if (curve25519_generate_public(public_key, private_key)) { + peer = pubkey_hashtable_lookup(&wg->peer_hashtable, public_key); + if (peer) { + peer_put(peer); + peer_remove(peer); + } } + noise_set_static_identity_private_key(&wg->static_identity, private_key); list_for_each_entry_safe(peer, temp, &wg->peer_list, peer_list) { if (!noise_precompute_static_static(peer)) |