[PATCH 0/3] pull request (net): ipsec 2022-05-18

[PATCH 0/3] pull request (net): ipsec 2022-05-18

[Steffen Klassert]

1) Fix "disable_policy" flag use when arriving from different devices.
   From Eyal Birger.

2) Fix error handling of pfkey_broadcast in function pfkey_process.
   From Jiasheng Jiang.

3) Check the encryption module availability consistency in pfkey.
   From Thomas Bartschies.

Please pull or let me know if there are problems.

Thanks!

The following changes since commit 79396934e289dbc501316c1d1f975bb4c88ae460:

  net: dsa: b53: convert to phylink_pcs (2022-05-01 17:51:06 +0100)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec.git master

for you to fetch changes up to 015c44d7bff3f44d569716117becd570c179ca32:

  net: af_key: check encryption module availability consistency (2022-05-18 09:42:16 +0200)

----------------------------------------------------------------
Eyal Birger (1):
      xfrm: fix "disable_policy" flag use when arriving from different devices

Jiasheng Jiang (1):
      net: af_key: add check for pfkey_broadcast in function pfkey_process

Thomas Bartschies (1):
      net: af_key: check encryption module availability consistency

 include/net/ip.h   |  1 +
 include/net/xfrm.h | 14 +++++++++++++-
 net/ipv4/route.c   | 23 ++++++++++++++++++-----
 net/key/af_key.c   | 12 +++++++-----
 4 files changed, 39 insertions(+), 11 deletions(-)

[PATCH 1/3] xfrm: fix "disable_policy" flag use when arriving from different devices

[Steffen Klassert]

From: Eyal Birger <eyal.birger@gmail.com>

In IPv4 setting the "disable_policy" flag on a device means no policy
should be enforced for traffic originating from the device. This was
implemented by seting the DST_NOPOLICY flag in the dst based on the
originating device.

However, dsts are cached in nexthops regardless of the originating
devices, in which case, the DST_NOPOLICY flag value may be incorrect.

Consider the following setup:

                     +------------------------------+
                     | ROUTER                       |
  +-------------+    | +-----------------+          |
  | ipsec src   |----|-|ipsec0           |          |
  +-------------+    | |disable_policy=0 |   +----+ |
                     | +-----------------+   |eth1|-|-----
  +-------------+    | +-----------------+   +----+ |
  | noipsec src |----|-|eth0             |          |
  +-------------+    | |disable_policy=1 |          |
                     | +-----------------+          |
                     +------------------------------+

Where ROUTER has a default route towards eth1.

dst entries for traffic arriving from eth0 would have DST_NOPOLICY
and would be cached and therefore can be reused by traffic originating
from ipsec0, skipping policy check.

Fix by setting a IPSKB_NOPOLICY flag in IPCB and observing it instead
of the DST in IN/FWD IPv4 policy checks.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/ip.h   |  1 +
 include/net/xfrm.h | 14 +++++++++++++-
 net/ipv4/route.c   | 23 ++++++++++++++++++-----
 3 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/include/net/ip.h b/include/net/ip.h
index 3984f2c39c4b..0161137914cf 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -56,6 +56,7 @@ struct inet_skb_parm {
 #define IPSKB_DOREDIRECT	BIT(5)
 #define IPSKB_FRAG_PMTU		BIT(6)
 #define IPSKB_L3SLAVE		BIT(7)
+#define IPSKB_NOPOLICY		BIT(8)
 
 	u16			frag_max_size;
 };
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 6fb899ff5afc..d2efddce65d4 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1093,6 +1093,18 @@ static inline bool __xfrm_check_nopolicy(struct net *net, struct sk_buff *skb,
 	return false;
 }
 
+static inline bool __xfrm_check_dev_nopolicy(struct sk_buff *skb,
+					     int dir, unsigned short family)
+{
+	if (dir != XFRM_POLICY_OUT && family == AF_INET) {
+		/* same dst may be used for traffic originating from
+		 * devices with different policy settings.
+		 */
+		return IPCB(skb)->flags & IPSKB_NOPOLICY;
+	}
+	return skb_dst(skb) && (skb_dst(skb)->flags & DST_NOPOLICY);
+}
+
 static inline int __xfrm_policy_check2(struct sock *sk, int dir,
 				       struct sk_buff *skb,
 				       unsigned int family, int reverse)
@@ -1104,7 +1116,7 @@ static inline int __xfrm_policy_check2(struct sock *sk, int dir,
 		return __xfrm_policy_check(sk, ndir, skb, family);
 
 	return __xfrm_check_nopolicy(net, skb, dir) ||
-	       (skb_dst(skb) && (skb_dst(skb)->flags & DST_NOPOLICY)) ||
+	       __xfrm_check_dev_nopolicy(skb, dir, family) ||
 	       __xfrm_policy_check(sk, ndir, skb, family);
 }
 
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 98c6f3429593..fe5d14ef5c4d 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1726,6 +1726,7 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	struct in_device *in_dev = __in_dev_get_rcu(dev);
 	unsigned int flags = RTCF_MULTICAST;
 	struct rtable *rth;
+	bool no_policy;
 	u32 itag = 0;
 	int err;
 
@@ -1736,8 +1737,12 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	if (our)
 		flags |= RTCF_LOCAL;
 
+	no_policy = IN_DEV_ORCONF(in_dev, NOPOLICY);
+	if (no_policy)
+		IPCB(skb)->flags |= IPSKB_NOPOLICY;
+
 	rth = rt_dst_alloc(dev_net(dev)->loopback_dev, flags, RTN_MULTICAST,
-			   IN_DEV_ORCONF(in_dev, NOPOLICY), false);
+			   no_policy, false);
 	if (!rth)
 		return -ENOBUFS;
 
@@ -1795,7 +1800,7 @@ static int __mkroute_input(struct sk_buff *skb,
 	struct rtable *rth;
 	int err;
 	struct in_device *out_dev;
-	bool do_cache;
+	bool do_cache, no_policy;
 	u32 itag = 0;
 
 	/* get a working reference to the output device */
@@ -1840,6 +1845,10 @@ static int __mkroute_input(struct sk_buff *skb,
 		}
 	}
 
+	no_policy = IN_DEV_ORCONF(in_dev, NOPOLICY);
+	if (no_policy)
+		IPCB(skb)->flags |= IPSKB_NOPOLICY;
+
 	fnhe = find_exception(nhc, daddr);
 	if (do_cache) {
 		if (fnhe)
@@ -1852,8 +1861,7 @@ static int __mkroute_input(struct sk_buff *skb,
 		}
 	}
 
-	rth = rt_dst_alloc(out_dev->dev, 0, res->type,
-			   IN_DEV_ORCONF(in_dev, NOPOLICY),
+	rth = rt_dst_alloc(out_dev->dev, 0, res->type, no_policy,
 			   IN_DEV_ORCONF(out_dev, NOXFRM));
 	if (!rth) {
 		err = -ENOBUFS;
@@ -2228,6 +2236,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	struct rtable	*rth;
 	struct flowi4	fl4;
 	bool do_cache = true;
+	bool no_policy;
 
 	/* IP on this device is disabled. */
 
@@ -2346,6 +2355,10 @@ out:	return err;
 	RT_CACHE_STAT_INC(in_brd);
 
 local_input:
+	no_policy = IN_DEV_ORCONF(in_dev, NOPOLICY);
+	if (no_policy)
+		IPCB(skb)->flags |= IPSKB_NOPOLICY;
+
 	do_cache &= res->fi && !itag;
 	if (do_cache) {
 		struct fib_nh_common *nhc = FIB_RES_NHC(*res);
@@ -2360,7 +2373,7 @@ out:	return err;
 
 	rth = rt_dst_alloc(ip_rt_get_dev(net, res),
 			   flags | RTCF_LOCAL, res->type,
-			   IN_DEV_ORCONF(in_dev, NOPOLICY), false);
+			   no_policy, false);
 	if (!rth)
 		goto e_nobufs;
 
-- 
2.25.1

[PATCH 2/3] net: af_key: add check for pfkey_broadcast in function pfkey_process

[Steffen Klassert]

From: Jiasheng Jiang <jiasheng@iscas.ac.cn>

If skb_clone() returns null pointer, pfkey_broadcast() will
return error.
Therefore, it should be better to check the return value of
pfkey_broadcast() and return error if fails.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/key/af_key.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/key/af_key.c b/net/key/af_key.c
index fd51db3be91c..92e9d75dba2f 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -2826,8 +2826,10 @@ static int pfkey_process(struct sock *sk, struct sk_buff *skb, const struct sadb
 	void *ext_hdrs[SADB_EXT_MAX];
 	int err;
 
-	pfkey_broadcast(skb_clone(skb, GFP_KERNEL), GFP_KERNEL,
-			BROADCAST_PROMISC_ONLY, NULL, sock_net(sk));
+	err = pfkey_broadcast(skb_clone(skb, GFP_KERNEL), GFP_KERNEL,
+			      BROADCAST_PROMISC_ONLY, NULL, sock_net(sk));
+	if (err)
+		return err;
 
 	memset(ext_hdrs, 0, sizeof(ext_hdrs));
 	err = parse_exthdrs(skb, hdr, ext_hdrs);
-- 
2.25.1

[PATCH 3/3] net: af_key: check encryption module availability consistency

[Steffen Klassert]

From: Thomas Bartschies <thomas.bartschies@cvk.de>

Since the recent introduction supporting the SM3 and SM4 hash algos for IPsec, the kernel
produces invalid pfkey acquire messages, when these encryption modules are disabled. This
happens because the availability of the algos wasn't checked in all necessary functions.
This patch adds these checks.

Signed-off-by: Thomas Bartschies <thomas.bartschies@cvk.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/key/af_key.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/key/af_key.c b/net/key/af_key.c
index 92e9d75dba2f..339d95df19d3 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -2900,7 +2900,7 @@ static int count_ah_combs(const struct xfrm_tmpl *t)
 			break;
 		if (!aalg->pfkey_supported)
 			continue;
-		if (aalg_tmpl_set(t, aalg))
+		if (aalg_tmpl_set(t, aalg) && aalg->available)
 			sz += sizeof(struct sadb_comb);
 	}
 	return sz + sizeof(struct sadb_prop);
@@ -2918,7 +2918,7 @@ static int count_esp_combs(const struct xfrm_tmpl *t)
 		if (!ealg->pfkey_supported)
 			continue;
 
-		if (!(ealg_tmpl_set(t, ealg)))
+		if (!(ealg_tmpl_set(t, ealg) && ealg->available))
 			continue;
 
 		for (k = 1; ; k++) {
@@ -2929,7 +2929,7 @@ static int count_esp_combs(const struct xfrm_tmpl *t)
 			if (!aalg->pfkey_supported)
 				continue;
 
-			if (aalg_tmpl_set(t, aalg))
+			if (aalg_tmpl_set(t, aalg) && aalg->available)
 				sz += sizeof(struct sadb_comb);
 		}
 	}
-- 
2.25.1

Re: [PATCH 1/3] xfrm: fix "disable_policy" flag use when arriving from different devices

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net.git (master)
by Steffen Klassert <steffen.klassert@secunet.com>:

On Wed, 18 May 2022 10:19:36 +0200 you wrote:
> From: Eyal Birger <eyal.birger@gmail.com>
> 
> In IPv4 setting the "disable_policy" flag on a device means no policy
> should be enforced for traffic originating from the device. This was
> implemented by seting the DST_NOPOLICY flag in the dst based on the
> originating device.
> 
> [...]

Here is the summary with links:
  - [1/3] xfrm: fix "disable_policy" flag use when arriving from different devices
    https://git.kernel.org/netdev/net/c/e6175a2ed1f1
  - [2/3] net: af_key: add check for pfkey_broadcast in function pfkey_process
    https://git.kernel.org/netdev/net/c/4dc2a5a8f675
  - [3/3] net: af_key: check encryption module availability consistency
    https://git.kernel.org/netdev/net/c/015c44d7bff3

You are awesome, thank you!
-- 
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