2014-06-07 21:25:25

by Dmitry Popov

[permalink] [raw]
Subject: [PATCH] ip_vti: Fix 'ip tunnel add' with 'key' parameters

ip tunnel add remote 10.2.2.1 local 10.2.2.2 mode vti ikey 1 okey 2
translates to p->iflags = VTI_ISVTI|GRE_KEY and p->i_key = 1, but GRE_KEY !=
TUNNEL_KEY, so ip_tunnel_ioctl would set i_key to 0 (same story with o_key)
making us unable to create vti tunnels with [io]key via ip tunnel.

We cannot simply translate GRE_KEY to TUNNEL_KEY (as GRE module does) because
vti_tunnels with same local/remote addresses but different ikeys will be treated
as different then. So, imo the best option here is to move p->i_flags&*_KEY
check for vti tunnels from ip_tunnel.c to ip_vti.c and to think about [io]_mark
field for ip_tunnel_parm in the future.

Signed-off-by: Dmitry Popov <[email protected]>
---
net/ipv4/ip_tunnel.c | 10 ++++++----
net/ipv4/ip_vti.c | 8 +++++++-
2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 2acc233..0a03ad1 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -747,10 +747,12 @@ int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
goto done;
if (p->iph.ttl)
p->iph.frag_off |= htons(IP_DF);
- if (!(p->i_flags&TUNNEL_KEY))
- p->i_key = 0;
- if (!(p->o_flags&TUNNEL_KEY))
- p->o_key = 0;
+ if (!(p->i_flags&VTI_ISVTI)) {
+ if (!(p->i_flags&TUNNEL_KEY))
+ p->i_key = 0;
+ if (!(p->o_flags&TUNNEL_KEY))
+ p->o_key = 0;
+ }

t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);

diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index 13ef00f..b8960f3 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -313,7 +313,13 @@ vti_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
return -EINVAL;
}

- p.i_flags |= VTI_ISVTI;
+ if (!(p.i_flags & GRE_KEY))
+ p.i_key = 0;
+ if (!(p.o_flags & GRE_KEY))
+ p.o_key = 0;
+
+ p.i_flags = VTI_ISVTI;
+
err = ip_tunnel_ioctl(dev, &p, cmd);
if (err)
return err;


2014-06-07 21:55:59

by Sergei Shtylyov

[permalink] [raw]
Subject: Re: [PATCH] ip_vti: Fix 'ip tunnel add' with 'key' parameters

hello.

On 06/08/2014 01:25 AM, Dmitry Popov wrote:

> ip tunnel add remote 10.2.2.1 local 10.2.2.2 mode vti ikey 1 okey 2
> translates to p->iflags = VTI_ISVTI|GRE_KEY and p->i_key = 1, but GRE_KEY !=
> TUNNEL_KEY, so ip_tunnel_ioctl would set i_key to 0 (same story with o_key)
> making us unable to create vti tunnels with [io]key via ip tunnel.

> We cannot simply translate GRE_KEY to TUNNEL_KEY (as GRE module does) because
> vti_tunnels with same local/remote addresses but different ikeys will be treated
> as different then. So, imo the best option here is to move p->i_flags&*_KEY
> check for vti tunnels from ip_tunnel.c to ip_vti.c and to think about [io]_mark
> field for ip_tunnel_parm in the future.

> Signed-off-by: Dmitry Popov <[email protected]>
> ---
> net/ipv4/ip_tunnel.c | 10 ++++++----
> net/ipv4/ip_vti.c | 8 +++++++-
> 2 files changed, 13 insertions(+), 5 deletions(-)

> diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
> index 2acc233..0a03ad1 100644
> --- a/net/ipv4/ip_tunnel.c
> +++ b/net/ipv4/ip_tunnel.c
> @@ -747,10 +747,12 @@ int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
> goto done;
> if (p->iph.ttl)
> p->iph.frag_off |= htons(IP_DF);
> - if (!(p->i_flags&TUNNEL_KEY))
> - p->i_key = 0;
> - if (!(p->o_flags&TUNNEL_KEY))
> - p->o_key = 0;
> + if (!(p->i_flags&VTI_ISVTI)) {
> + if (!(p->i_flags&TUNNEL_KEY))
> + p->i_key = 0;
> + if (!(p->o_flags&TUNNEL_KEY))

Please surround & with spaces for consistency; this also would follow the
general kernel coding style.

[...]

WBR, Sergei

2014-06-07 22:01:09

by Dmitry Popov

[permalink] [raw]
Subject: Re: [PATCH] ip_vti: Fix 'ip tunnel add' with 'key' parameters

On Sun, 08 Jun 2014 01:55:22 +0400
Sergei Shtylyov <[email protected]> wrote:

> Please surround & with spaces for consistency; this also would follow the
> general kernel coding style.

> WBR, Sergei
>

Okay, original code was without spaces, didn't want to break this, I will resend.