From: Fan Du Date: Tue, 17 Sep 2013 07:14:13 +0000 (+0800) Subject: xfrm: Guard IPsec anti replay window against replay bitmap X-Git-Tag: firefly_0821_release~176^2~5117^2~46^2~3 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=33fce60d6a6e137035f8e23a89d7fd55f3a24cda;p=firefly-linux-kernel-4.4.55.git xfrm: Guard IPsec anti replay window against replay bitmap For legacy IPsec anti replay mechanism: bitmap in struct xfrm_replay_state could only provide a 32 bits window size limit in current design, thus user level parameter sadb_sa_replay should honor this limit, otherwise misleading outputs("replay=244") by setkey -D will be: 192.168.25.2 192.168.22.2 esp mode=transport spi=147561170(0x08cb9ad2) reqid=0(0x00000000) E: aes-cbc 9a8d7468 7655cf0b 719d27be b0ddaac2 A: hmac-sha1 2d2115c2 ebf7c126 1c54f186 3b139b58 264a7331 seq=0x00000000 replay=244 flags=0x00000000 state=mature created: Sep 17 14:00:00 2013 current: Sep 17 14:00:22 2013 diff: 22(s) hard: 30(s) soft: 26(s) last: Sep 17 14:00:00 2013 hard: 0(s) soft: 0(s) current: 1408(bytes) hard: 0(bytes) soft: 0(bytes) allocated: 22 hard: 0 soft: 0 sadb_seq=1 pid=4854 refcnt=0 192.168.22.2 192.168.25.2 esp mode=transport spi=255302123(0x0f3799eb) reqid=0(0x00000000) E: aes-cbc 6485d990 f61a6bd5 e5660252 608ad282 A: hmac-sha1 0cca811a eb4fa893 c47ae56c 98f6e413 87379a88 seq=0x00000000 replay=244 flags=0x00000000 state=mature created: Sep 17 14:00:00 2013 current: Sep 17 14:00:22 2013 diff: 22(s) hard: 30(s) soft: 26(s) last: Sep 17 14:00:00 2013 hard: 0(s) soft: 0(s) current: 1408(bytes) hard: 0(bytes) soft: 0(bytes) allocated: 22 hard: 0 soft: 0 sadb_seq=0 pid=4854 refcnt=0 And also, optimizing xfrm_replay_check window checking by setting the desirable x->props.replay_window with only doing the comparison once for all when xfrm_state is first born. Signed-off-by: Fan Du Signed-off-by: Steffen Klassert --- diff --git a/net/key/af_key.c b/net/key/af_key.c index 9d585370c5b4..911ef03bf8fb 100644 --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -1098,7 +1098,8 @@ static struct xfrm_state * pfkey_msg2xfrm_state(struct net *net, x->id.proto = proto; x->id.spi = sa->sadb_sa_spi; - x->props.replay_window = sa->sadb_sa_replay; + x->props.replay_window = min_t(unsigned int, sa->sadb_sa_replay, + (sizeof(x->replay.bitmap) * 8)); if (sa->sadb_sa_flags & SADB_SAFLAGS_NOECN) x->props.flags |= XFRM_STATE_NOECN; if (sa->sadb_sa_flags & SADB_SAFLAGS_DECAP_DSCP) diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c index 8dafe6d3c6e4..eeca388effc7 100644 --- a/net/xfrm/xfrm_replay.c +++ b/net/xfrm/xfrm_replay.c @@ -129,8 +129,7 @@ static int xfrm_replay_check(struct xfrm_state *x, return 0; diff = x->replay.seq - seq; - if (diff >= min_t(unsigned int, x->props.replay_window, - sizeof(x->replay.bitmap) * 8)) { + if (diff >= x->props.replay_window) { x->stats.replay_window++; goto err; } diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 4b26ceedff26..f964d4c00ffb 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -446,7 +446,8 @@ static void copy_from_user_state(struct xfrm_state *x, struct xfrm_usersa_info * memcpy(&x->sel, &p->sel, sizeof(x->sel)); memcpy(&x->lft, &p->lft, sizeof(x->lft)); x->props.mode = p->mode; - x->props.replay_window = p->replay_window; + x->props.replay_window = min_t(unsigned int, p->replay_window, + sizeof(x->replay.bitmap) * 8); x->props.reqid = p->reqid; x->props.family = p->family; memcpy(&x->props.saddr, &p->saddr, sizeof(x->props.saddr));