diff options
author | Steffen Klassert <steffen.klassert@secunet.com> | 2021-07-18 09:11:06 +0200 |
---|---|---|
committer | Steffen Klassert <steffen.klassert@secunet.com> | 2021-07-21 09:49:19 +0200 |
commit | 2d151d39073aff498358543801fca0f670fea981 (patch) | |
tree | 76abb9648c571bb6fc5ccb5d7c25f000e22c1273 /net/xfrm/xfrm_policy.c | |
parent | f8fdadef92b7a39e9a9a83bc2df68731ac6c298b (diff) |
xfrm: Add possibility to set the default to block if we have no policy
As the default we assume the traffic to pass, if we have no
matching IPsec policy. With this patch, we have a possibility to
change this default from allow to block. It can be configured
via netlink. Each direction (input/output/forward) can be
configured separately. With the default to block configuered,
we need allow policies for all packet flows we accept.
We do not use default policy lookup for the loopback device.
v1->v2
- fix compiling when XFRM is disabled
- Reported-by: kernel test robot <lkp@intel.com>
Co-developed-by: Christian Langrock <christian.langrock@secunet.com>
Signed-off-by: Christian Langrock <christian.langrock@secunet.com>
Co-developed-by: Antony Antony <antony.antony@secunet.com>
Signed-off-by: Antony Antony <antony.antony@secunet.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Diffstat (limited to 'net/xfrm/xfrm_policy.c')
-rw-r--r-- | net/xfrm/xfrm_policy.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 827d84255021..d5cb082e11fc 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -3165,6 +3165,11 @@ ok: return dst; nopol: + if (!(dst_orig->dev->flags & IFF_LOOPBACK) && + !xfrm_default_allow(net, dir)) { + err = -EPERM; + goto error; + } if (!(flags & XFRM_LOOKUP_ICMP)) { dst = dst_orig; goto ok; @@ -3553,6 +3558,11 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, } if (!pol) { + if (!xfrm_default_allow(net, dir)) { + XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); + return 0; + } + if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { xfrm_secpath_reject(xerr_idx, skb, &fl); XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); @@ -3607,6 +3617,12 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, tpp[ti++] = &pols[pi]->xfrm_vec[i]; } xfrm_nr = ti; + + if (!xfrm_default_allow(net, dir) && !xfrm_nr) { + XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); + goto reject; + } + if (npols > 1) { xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); tpp = stp; |