diff options
| author | Jason A. Donenfeld <Jason@zx2c4.com> | 2017-09-22 04:04:00 +0200 |
|---|---|---|
| committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2017-09-24 23:10:15 +0200 |
| commit | 14b46145b769adb1903f48415659d69be3cf986e (patch) | |
| tree | 25e5c9e9c61baa38bf8457cf4dc081665cef9597 | |
| parent | 875b45f7b010200de8836cd3773af3ad9fbee0fb (diff) | |
tools: use key_is_zero for comparing to zeros
Maybe an attacker on the system could use the infoleak in /proc to gauge
how long a wg(8) process takes to complete and determine the number of
leading zeros. This is somewhat ridiculous, but it's possible somebody
somewhere might at somepoint care in the future, so alright.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
| -rw-r--r-- | src/config.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/src/config.c b/src/config.c index af7d049..a4a6782 100644 --- a/src/config.c +++ b/src/config.c @@ -8,6 +8,7 @@ #include "hashtables.h" #include "peer.h" #include "uapi.h" +#include <crypto/algapi.h> static int set_device_port(struct wireguard_device *wg, u16 port) { @@ -86,7 +87,7 @@ static int set_peer(struct wireguard_device *wg, void __user *user_peer, size_t down_write(&peer->handshake.lock); memset(&peer->handshake.preshared_key, 0, NOISE_SYMMETRIC_KEY_LEN); up_write(&peer->handshake.lock); - } else if (memcmp(zeros, in_peer.preshared_key, WG_KEY_LEN)) { + } else if (crypto_memneq(zeros, in_peer.preshared_key, WG_KEY_LEN)) { down_write(&peer->handshake.lock); memcpy(&peer->handshake.preshared_key, in_peer.preshared_key, NOISE_SYMMETRIC_KEY_LEN); up_write(&peer->handshake.lock); @@ -165,7 +166,7 @@ int config_set_device(struct wireguard_device *wg, void __user *user_device) if (in_device.flags & WGDEVICE_REMOVE_PRIVATE_KEY) { noise_set_static_identity_private_key(&wg->static_identity, NULL); modified_static_identity = true; - } else if (memcmp(zeros, in_device.private_key, WG_KEY_LEN)) { + } else if (crypto_memneq(zeros, in_device.private_key, WG_KEY_LEN)) { u8 public_key[NOISE_PUBLIC_KEY_LEN] = { 0 }; struct wireguard_peer *peer; /* We remove before setting, to prevent race, which means doing two 25519-genpub ops. */ |