[PATCH v2 0/2] Add UID/GID info to NFQUEUE

[PATCH v2 0/2] Add UID/GID info to NFQUEUE

[valentina.giusti]

From: Valentina Giusti <valentina.giusti@oss.bmw-carit.de>

Hi,

here is the second version of this patchset, modified in accordance with Florian
Westphal's comments to the first version.

I hope this one looks better :)

--
Best Regards,
Val

[PATCH v2 1/2] netfilter_queue: enable UID/GID socket info retrieval

[valentina.giusti]

From: Valentina Giusti <valentina.giusti@oss.bmw-carit.de>

Thanks to commits 41063e9 (ipv4: Early TCP socket demux) and 421b388 (udp: ipv4:
Add udp early demux) it is now possible to parse UID and GID socket info
also for incoming TCP and UDP connections. Having this info available, it
is convenient to let NFQUEUE parse it in order to improve and refine the
traffic analysis in userspace.

Signed-off-by: Valentina Giusti <valentina.giusti@bmw-carit.de>
---
 include/uapi/linux/netfilter/nfnetlink_queue.h |  5 ++++-
 net/netfilter/nfnetlink_queue_core.c           | 31 ++++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/netfilter/nfnetlink_queue.h b/include/uapi/linux/netfilter/nfnetlink_queue.h
index 0132bad..8dd819e 100644
--- a/include/uapi/linux/netfilter/nfnetlink_queue.h
+++ b/include/uapi/linux/netfilter/nfnetlink_queue.h
@@ -47,6 +47,8 @@ enum nfqnl_attr_type {
 	NFQA_CAP_LEN,			/* __u32 length of captured packet */
 	NFQA_SKB_INFO,			/* __u32 skb meta information */
 	NFQA_EXP,			/* nf_conntrack_netlink.h */
+	NFQA_UID,			/* __u32 sk uid */
+	NFQA_GID,			/* __u32 sk gid */
 
 	__NFQA_MAX
 };
@@ -99,7 +101,8 @@ enum nfqnl_attr_config {
 #define NFQA_CFG_F_FAIL_OPEN			(1 << 0)
 #define NFQA_CFG_F_CONNTRACK			(1 << 1)
 #define NFQA_CFG_F_GSO				(1 << 2)
-#define NFQA_CFG_F_MAX				(1 << 3)
+#define NFQA_CFG_F_UID_GID			(1 << 3)
+#define NFQA_CFG_F_MAX				(1 << 4)
 
 /* flags for NFQA_SKB_INFO */
 /* packet appears to have wrong checksums, but they are ok */
diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c
index 21258cf..2cdef07 100644
--- a/net/netfilter/nfnetlink_queue_core.c
+++ b/net/netfilter/nfnetlink_queue_core.c
@@ -297,6 +297,29 @@ nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
 	return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
 }
 
+static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
+{
+	const struct cred *cred;
+
+	if (sk && sk->sk_state != TCP_TIME_WAIT) {
+		read_lock_bh(&sk->sk_callback_lock);
+		if (sk->sk_socket && sk->sk_socket->file) {
+			cred = sk->sk_socket->file->f_cred;
+			if (nla_put_u32(skb, NFQA_UID, htonl(cred->fsuid)))
+				goto nla_put_failure;
+			if (nla_put_u32(skb, NFQA_GID, htonl(cred->fsgid)))
+				goto nla_put_failure;
+		}
+		read_unlock_bh(&sk->sk_callback_lock);
+	}
+
+	return 0;
+
+nla_put_failure:
+	read_unlock_bh(&sk->sk_callback_lock);
+	return -1;
+}
+
 static struct sk_buff *
 nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 			   struct nf_queue_entry *entry,
@@ -372,6 +395,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	if (queue->flags & NFQA_CFG_F_CONNTRACK)
 		ct = nfqnl_ct_get(entskb, &size, &ctinfo);
 
+	if (queue->flags & NFQA_CFG_F_UID_GID)
+		size +=  (nla_total_size(sizeof(u_int32_t))	/* uid */
+			+ nla_total_size(sizeof(u_int32_t)));	/* gid */
+
 	skb = nfnetlink_alloc_skb(net, size, queue->peer_portid,
 				  GFP_ATOMIC);
 	if (!skb)
@@ -484,6 +511,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 			goto nla_put_failure;
 	}
 
+	if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk)
+		if (nfqnl_put_sk_uidgid(skb, entskb->sk))
+			goto nla_put_failure;
+
 	if (ct && nfqnl_ct_put(skb, ct, ctinfo) < 0)
 		goto nla_put_failure;
 
-- 
1.8.5.1

[PATCH v2 2/2] libnetfilter_queue: add support for UID/GID socket info

[valentina.giusti]

From: Valentina Giusti <Valentina.Giusti@bmw-carit.de>

With this patch libnetfilter_queue is able to parse UID/GID
socket information.

Signed-off-by: Valentina Giusti <Valentina.Giusti@bmw-carit.de>
---
 include/libnetfilter_queue/libnetfilter_queue.h    |  4 ++++
 include/libnetfilter_queue/linux_nfnetlink_queue.h |  5 +++-
 include/linux/netfilter/nfnetlink_queue.h          |  6 ++++-
 src/libnetfilter_queue.c                           | 28 ++++++++++++++++++++++
 src/nlmsg.c                                        |  2 ++
 5 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/include/libnetfilter_queue/libnetfilter_queue.h b/include/libnetfilter_queue/libnetfilter_queue.h
index b9f16e2..b4e2679 100644
--- a/include/libnetfilter_queue/libnetfilter_queue.h
+++ b/include/libnetfilter_queue/libnetfilter_queue.h
@@ -103,6 +103,8 @@ extern u_int32_t nfq_get_indev(struct nfq_data *nfad);
 extern u_int32_t nfq_get_physindev(struct nfq_data *nfad);
 extern u_int32_t nfq_get_outdev(struct nfq_data *nfad);
 extern u_int32_t nfq_get_physoutdev(struct nfq_data *nfad);
+extern u_int32_t nfq_get_uid(struct nfq_data *nfad);
+extern u_int32_t nfq_get_gid(struct nfq_data *nfad);
 
 extern int nfq_get_indev_name(struct nlif_handle *nlif_handle,
 			      struct nfq_data *nfad, char *name);
@@ -125,6 +127,8 @@ enum {
 	NFQ_XML_PHYSDEV	= (1 << 3),
 	NFQ_XML_PAYLOAD	= (1 << 4),
 	NFQ_XML_TIME	= (1 << 5),
+	NFQ_XML_UID	= (1 << 6),
+	NFQ_XML_GID	= (1 << 7),
 	NFQ_XML_ALL	= ~0U,
 };
 
diff --git a/include/libnetfilter_queue/linux_nfnetlink_queue.h b/include/libnetfilter_queue/linux_nfnetlink_queue.h
index 81a485b..884ab0e 100644
--- a/include/libnetfilter_queue/linux_nfnetlink_queue.h
+++ b/include/libnetfilter_queue/linux_nfnetlink_queue.h
@@ -50,6 +50,8 @@ enum nfqnl_attr_type {
 	NFQA_CAP_LEN,                   /* __u32 length of captured packet */
 	NFQA_SKB_INFO,                  /* __u32 skb meta information */
 
+	NFQA_UID,			/* __u32 sk uid */
+	NFQA_GID,			/* __u32 sk gid */
 	__NFQA_MAX
 };
 #define NFQA_MAX (__NFQA_MAX - 1)
@@ -101,7 +103,8 @@ enum nfqnl_attr_config {
 #define NFQA_CFG_F_FAIL_OPEN		(1 << 0)
 #define NFQA_CFG_F_CONNTRACK		(1 << 1)
 #define NFQA_CFG_F_GSO			(1 << 2)
-#define NFQA_CFG_F_MAX			(1 << 3)
+#define NFQA_CFG_F_UID_GID		(1 << 3)
+#define NFQA_CFG_F_MAX			(1 << 4)
 
 /* flags for NFQA_SKB_INFO */
 /* packet appears to have wrong checksums, but they are ok */
diff --git a/include/linux/netfilter/nfnetlink_queue.h b/include/linux/netfilter/nfnetlink_queue.h
index a2308ae..22f5d45 100644
--- a/include/linux/netfilter/nfnetlink_queue.h
+++ b/include/linux/netfilter/nfnetlink_queue.h
@@ -46,6 +46,9 @@ enum nfqnl_attr_type {
 	NFQA_CT_INFO,			/* enum ip_conntrack_info */
 	NFQA_CAP_LEN,			/* __u32 length of captured packet */
 	NFQA_SKB_INFO,			/* __u32 skb meta information */
+	NFQA_EXP,			/* nf_conntrack_netlink.h */
+	NFQA_UID,			/* __u32 sk uid */
+	NFQA_GID,			/* __u32 sk gid */
 
 	__NFQA_MAX
 };
@@ -98,7 +101,8 @@ enum nfqnl_attr_config {
 #define NFQA_CFG_F_FAIL_OPEN			(1 << 0)
 #define NFQA_CFG_F_CONNTRACK			(1 << 1)
 #define NFQA_CFG_F_GSO				(1 << 2)
-#define NFQA_CFG_F_MAX				(1 << 3)
+#define NFQA_CFG_F_UID_GID			(1 << 3)
+#define NFQA_CFG_F_MAX				(1 << 4)
 
 /* flags for NFQA_SKB_INFO */
 /* packet appears to have wrong checksums, but they are ok */
diff --git a/src/libnetfilter_queue.c b/src/libnetfilter_queue.c
index fa8efe7..bf1266b 100644
--- a/src/libnetfilter_queue.c
+++ b/src/libnetfilter_queue.c
@@ -668,6 +668,9 @@ EXPORT_SYMBOL(nfq_set_mode);
  *  if this bit is set, the layer 3/4 checksums of the packet appear incorrect,
  *  but are not (because they will be corrected later by the kernel).
  *
+ *  - NFQA_CFG_F_UID_GID: the kernel will dump UID and GID of the socket to
+ *  which each packet belongs.
+ *
  * Here's a little code snippet to show how to use this API:
  * \verbatim
 	uint32_t flags = NFQA_CFG_F_FAIL_OPEN;
@@ -1180,6 +1183,18 @@ struct nfqnl_msg_packet_hw *nfq_get_packet_hw(struct nfq_data *nfad)
 }
 EXPORT_SYMBOL(nfq_get_packet_hw);
 
+uint32_t nfq_get_uid(struct nfq_data *nfad)
+{
+	return ntohl(nfnl_get_data(nfad->data, NFQA_UID, u_int32_t));
+}
+EXPORT_SYMBOL(nfq_get_uid);
+
+uint32_t nfq_get_gid(struct nfq_data *nfad)
+{
+	return ntohl(nfnl_get_data(nfad->data, NFQA_GID, u_int32_t));
+}
+EXPORT_SYMBOL(nfq_get_gid);
+
 /**
  * nfq_get_payload - get payload 
  * \param nfad Netlink packet data handle passed to callback function
@@ -1250,6 +1265,7 @@ int nfq_snprintf_xml(char *buf, size_t rem, struct nfq_data *tb, int flags)
 	struct nfqnl_msg_packet_hdr *ph;
 	struct nfqnl_msg_packet_hw *hwph;
 	u_int32_t mark, ifi;
+	u_int32_t uid, gid;
 	int size, offset = 0, len = 0, ret;
 	unsigned char *data;
 
@@ -1365,6 +1381,18 @@ int nfq_snprintf_xml(char *buf, size_t rem, struct nfq_data *tb, int flags)
 		SNPRINTF_FAILURE(size, rem, offset, len);
 	}
 
+	uid = nfq_get_uid(tb);
+	if (uid && (flags & NFQ_XML_UID)) {
+		size = snprintf(buf + offset, rem, "<uid>%u</uid>", uid);
+		SNPRINTF_FAILURE(size, rem, offset, len);
+	}
+
+	gid = nfq_get_gid(tb);
+	if (gid && (flags & NFQ_XML_GID)) {
+		size = snprintf(buf + offset, rem, "<gid>%u</gid>", gid);
+		SNPRINTF_FAILURE(size, rem, offset, len);
+	}
+
 	ret = nfq_get_payload(tb, &data);
 	if (ret >= 0 && (flags & NFQ_XML_PAYLOAD)) {
 		int i;
diff --git a/src/nlmsg.c b/src/nlmsg.c
index e7a30e0..81e170e 100644
--- a/src/nlmsg.c
+++ b/src/nlmsg.c
@@ -134,6 +134,8 @@ static int nfq_pkt_parse_attr_cb(const struct nlattr *attr, void *data)
 	case NFQA_IFINDEX_PHYSOUTDEV:
 	case NFQA_CAP_LEN:
 	case NFQA_SKB_INFO:
+	case NFQA_UID:
+	case NFQA_GID:
 		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
 			return MNL_CB_ERROR;
 		break;
-- 
1.8.5.1

Re: [PATCH v2 1/2] netfilter_queue: enable UID/GID socket info retrieval

[Florian Westphal]

valentina.giusti@bmw-carit.de <valentina.giusti@bmw-carit.de> wrote:
> From: Valentina Giusti <valentina.giusti@oss.bmw-carit.de>
> 
> Thanks to commits 41063e9 (ipv4: Early TCP socket demux) and 421b388 (udp: ipv4:
> Add udp early demux) it is now possible to parse UID and GID socket info
> also for incoming TCP and UDP connections. Having this info available, it
> is convenient to let NFQUEUE parse it in order to improve and refine the
> traffic analysis in userspace.

> diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c
> index 21258cf..2cdef07 100644
> --- a/net/netfilter/nfnetlink_queue_core.c
> +++ b/net/netfilter/nfnetlink_queue_core.c
> @@ -297,6 +297,29 @@ nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
>  	return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
>  }
>  
> +static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
> +{
> +	const struct cred *cred;
> +
> +	if (sk && sk->sk_state != TCP_TIME_WAIT) {
[..]
> +	if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk)
> +		if (nfqnl_put_sk_uidgid(skb, entskb->sk))
> +			goto nla_put_failure;

Minor nit: sk is tested for non-null twice.  Suggestion:

if ((queue->flags & NFQA_CFG_F_UID_GID) &&
     nfqnl_put_sk_uidgid(skb, entskb->sk))
          goto nla_put_failure;

I don't think its necessary to resubmit the patch though, thus:

Reviewed-by: Florian Westphal <fw@strlen.de>

Re: [PATCH v2 1/2] netfilter_queue: enable UID/GID socket info retrieval

[Pablo Neira Ayuso]

Hi,

On Thu, Dec 19, 2013 at 12:03:26PM +0100, valentina.giusti@bmw-carit.de wrote:
> From: Valentina Giusti <valentina.giusti@oss.bmw-carit.de>
> 
> Thanks to commits 41063e9 (ipv4: Early TCP socket demux) and 421b388 (udp: ipv4:
> Add udp early demux) it is now possible to parse UID and GID socket info
> also for incoming TCP and UDP connections. Having this info available, it
> is convenient to let NFQUEUE parse it in order to improve and refine the
> traffic analysis in userspace.
> 
> Signed-off-by: Valentina Giusti <valentina.giusti@bmw-carit.de>
> ---
>  include/uapi/linux/netfilter/nfnetlink_queue.h |  5 ++++-
>  net/netfilter/nfnetlink_queue_core.c           | 31 ++++++++++++++++++++++++++
>  2 files changed, 35 insertions(+), 1 deletion(-)
> 
> diff --git a/include/uapi/linux/netfilter/nfnetlink_queue.h b/include/uapi/linux/netfilter/nfnetlink_queue.h
> index 0132bad..8dd819e 100644
> --- a/include/uapi/linux/netfilter/nfnetlink_queue.h
> +++ b/include/uapi/linux/netfilter/nfnetlink_queue.h
> @@ -47,6 +47,8 @@ enum nfqnl_attr_type {
>  	NFQA_CAP_LEN,			/* __u32 length of captured packet */
>  	NFQA_SKB_INFO,			/* __u32 skb meta information */
>  	NFQA_EXP,			/* nf_conntrack_netlink.h */
> +	NFQA_UID,			/* __u32 sk uid */
> +	NFQA_GID,			/* __u32 sk gid */
>  
>  	__NFQA_MAX
>  };
> @@ -99,7 +101,8 @@ enum nfqnl_attr_config {
>  #define NFQA_CFG_F_FAIL_OPEN			(1 << 0)
>  #define NFQA_CFG_F_CONNTRACK			(1 << 1)
>  #define NFQA_CFG_F_GSO				(1 << 2)
> -#define NFQA_CFG_F_MAX				(1 << 3)
> +#define NFQA_CFG_F_UID_GID			(1 << 3)
> +#define NFQA_CFG_F_MAX				(1 << 4)
>  
>  /* flags for NFQA_SKB_INFO */
>  /* packet appears to have wrong checksums, but they are ok */
> diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c
> index 21258cf..2cdef07 100644
> --- a/net/netfilter/nfnetlink_queue_core.c
> +++ b/net/netfilter/nfnetlink_queue_core.c
> @@ -297,6 +297,29 @@ nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
>  	return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
>  }
>  
> +static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
> +{
> +	const struct cred *cred;
> +
> +	if (sk && sk->sk_state != TCP_TIME_WAIT) {
> +		read_lock_bh(&sk->sk_callback_lock);
> +		if (sk->sk_socket && sk->sk_socket->file) {
> +			cred = sk->sk_socket->file->f_cred;
> +			if (nla_put_u32(skb, NFQA_UID, htonl(cred->fsuid)))

I'm hitting this compilation error here:

net/netfilter/nfnetlink_queue_core.c: In function ‘nfqnl_put_sk_uidgid’:
net/netfilter/nfnetlink_queue_core.c:308:4: error: aggregate value used where an integer was expected

It seems that in recent kernels you have to use:

        from_kuid_munged(&init_user_ns, cred->fsuid);

to retrieve the integer that represents the uid.

Please, 


> +				goto nla_put_failure;
> +			if (nla_put_u32(skb, NFQA_GID, htonl(cred->fsgid)))
                                    ^^^

Minor nitpick: This has to be _be32 otherwise sparse will complain
(spotted by Florian Westphal).

Make sure you patch is also clean when running make C=2.

Also remove the extra checking for socket that Florian mentioned and
resubmit. Thanks.

Re: [PATCH v2 1/2] netfilter_queue: enable UID/GID socket info retrieval

[Pablo Neira Ayuso]

On Fri, Dec 20, 2013 at 10:26:38AM +0100, Pablo Neira Ayuso wrote:
> Hi,
> 
> On Thu, Dec 19, 2013 at 12:03:26PM +0100, valentina.giusti@bmw-carit.de wrote:
> > From: Valentina Giusti <valentina.giusti@oss.bmw-carit.de>
> > 
> > Thanks to commits 41063e9 (ipv4: Early TCP socket demux) and 421b388 (udp: ipv4:
> > Add udp early demux) it is now possible to parse UID and GID socket info
> > also for incoming TCP and UDP connections. Having this info available, it
> > is convenient to let NFQUEUE parse it in order to improve and refine the
> > traffic analysis in userspace.
> > 
> > Signed-off-by: Valentina Giusti <valentina.giusti@bmw-carit.de>
> > ---
> >  include/uapi/linux/netfilter/nfnetlink_queue.h |  5 ++++-
> >  net/netfilter/nfnetlink_queue_core.c           | 31 ++++++++++++++++++++++++++
> >  2 files changed, 35 insertions(+), 1 deletion(-)
> > 
> > diff --git a/include/uapi/linux/netfilter/nfnetlink_queue.h b/include/uapi/linux/netfilter/nfnetlink_queue.h
> > index 0132bad..8dd819e 100644
> > --- a/include/uapi/linux/netfilter/nfnetlink_queue.h
> > +++ b/include/uapi/linux/netfilter/nfnetlink_queue.h
> > @@ -47,6 +47,8 @@ enum nfqnl_attr_type {
> >  	NFQA_CAP_LEN,			/* __u32 length of captured packet */
> >  	NFQA_SKB_INFO,			/* __u32 skb meta information */
> >  	NFQA_EXP,			/* nf_conntrack_netlink.h */
> > +	NFQA_UID,			/* __u32 sk uid */
> > +	NFQA_GID,			/* __u32 sk gid */
> >  
> >  	__NFQA_MAX
> >  };
> > @@ -99,7 +101,8 @@ enum nfqnl_attr_config {
> >  #define NFQA_CFG_F_FAIL_OPEN			(1 << 0)
> >  #define NFQA_CFG_F_CONNTRACK			(1 << 1)
> >  #define NFQA_CFG_F_GSO				(1 << 2)
> > -#define NFQA_CFG_F_MAX				(1 << 3)
> > +#define NFQA_CFG_F_UID_GID			(1 << 3)
> > +#define NFQA_CFG_F_MAX				(1 << 4)
> >  
> >  /* flags for NFQA_SKB_INFO */
> >  /* packet appears to have wrong checksums, but they are ok */
> > diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c
> > index 21258cf..2cdef07 100644
> > --- a/net/netfilter/nfnetlink_queue_core.c
> > +++ b/net/netfilter/nfnetlink_queue_core.c
> > @@ -297,6 +297,29 @@ nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
> >  	return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
> >  }
> >  
> > +static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
> > +{
> > +	const struct cred *cred;
> > +
> > +	if (sk && sk->sk_state != TCP_TIME_WAIT) {
> > +		read_lock_bh(&sk->sk_callback_lock);
> > +		if (sk->sk_socket && sk->sk_socket->file) {
> > +			cred = sk->sk_socket->file->f_cred;
> > +			if (nla_put_u32(skb, NFQA_UID, htonl(cred->fsuid)))
> 
> I'm hitting this compilation error here:
> 
> net/netfilter/nfnetlink_queue_core.c: In function ‘nfqnl_put_sk_uidgid’:
> net/netfilter/nfnetlink_queue_core.c:308:4: error: aggregate value used where an integer was expected
> 
> It seems that in recent kernels you have to use:
> 
>         from_kuid_munged(&init_user_ns, cred->fsuid);
> 
> to retrieve the integer that represents the uid.
> 
> Please, 

sorry, I left this sentence incomplete, I was telling... Please, test
your patches with current git trees :-). Thanks.

Re: [PATCH v2 1/2] netfilter_queue: enable UID/GID socket info retrieval

[Valentina Giusti]

Hi,

On 12/20/2013 10:29 AM, Pablo Neira Ayuso wrote:
> On Fri, Dec 20, 2013 at 10:26:38AM +0100, Pablo Neira Ayuso wrote:
>> Hi,
>>
>> On Thu, Dec 19, 2013 at 12:03:26PM +0100, valentina.giusti@bmw-carit.de wrote:
>>> From: Valentina Giusti <valentina.giusti@oss.bmw-carit.de>
>>>
>>> Thanks to commits 41063e9 (ipv4: Early TCP socket demux) and 421b388 (udp: ipv4:
>>> Add udp early demux) it is now possible to parse UID and GID socket info
>>> also for incoming TCP and UDP connections. Having this info available, it
>>> is convenient to let NFQUEUE parse it in order to improve and refine the
>>> traffic analysis in userspace.
>>>
>>> Signed-off-by: Valentina Giusti <valentina.giusti@bmw-carit.de>
>>> ---
>>>   include/uapi/linux/netfilter/nfnetlink_queue.h |  5 ++++-
>>>   net/netfilter/nfnetlink_queue_core.c           | 31 ++++++++++++++++++++++++++
>>>   2 files changed, 35 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/include/uapi/linux/netfilter/nfnetlink_queue.h b/include/uapi/linux/netfilter/nfnetlink_queue.h
>>> index 0132bad..8dd819e 100644
>>> --- a/include/uapi/linux/netfilter/nfnetlink_queue.h
>>> +++ b/include/uapi/linux/netfilter/nfnetlink_queue.h
>>> @@ -47,6 +47,8 @@ enum nfqnl_attr_type {
>>>   	NFQA_CAP_LEN,			/* __u32 length of captured packet */
>>>   	NFQA_SKB_INFO,			/* __u32 skb meta information */
>>>   	NFQA_EXP,			/* nf_conntrack_netlink.h */
>>> +	NFQA_UID,			/* __u32 sk uid */
>>> +	NFQA_GID,			/* __u32 sk gid */
>>>   
>>>   	__NFQA_MAX
>>>   };
>>> @@ -99,7 +101,8 @@ enum nfqnl_attr_config {
>>>   #define NFQA_CFG_F_FAIL_OPEN			(1 << 0)
>>>   #define NFQA_CFG_F_CONNTRACK			(1 << 1)
>>>   #define NFQA_CFG_F_GSO				(1 << 2)
>>> -#define NFQA_CFG_F_MAX				(1 << 3)
>>> +#define NFQA_CFG_F_UID_GID			(1 << 3)
>>> +#define NFQA_CFG_F_MAX				(1 << 4)
>>>   
>>>   /* flags for NFQA_SKB_INFO */
>>>   /* packet appears to have wrong checksums, but they are ok */
>>> diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c
>>> index 21258cf..2cdef07 100644
>>> --- a/net/netfilter/nfnetlink_queue_core.c
>>> +++ b/net/netfilter/nfnetlink_queue_core.c
>>> @@ -297,6 +297,29 @@ nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
>>>   	return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
>>>   }
>>>   
>>> +static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
>>> +{
>>> +	const struct cred *cred;
>>> +
>>> +	if (sk && sk->sk_state != TCP_TIME_WAIT) {
>>> +		read_lock_bh(&sk->sk_callback_lock);
>>> +		if (sk->sk_socket && sk->sk_socket->file) {
>>> +			cred = sk->sk_socket->file->f_cred;
>>> +			if (nla_put_u32(skb, NFQA_UID, htonl(cred->fsuid)))
>> I'm hitting this compilation error here:
>>
>> net/netfilter/nfnetlink_queue_core.c: In function ‘nfqnl_put_sk_uidgid’:
>> net/netfilter/nfnetlink_queue_core.c:308:4: error: aggregate value used where an integer was expected
>>
>> It seems that in recent kernels you have to use:
>>
>>          from_kuid_munged(&init_user_ns, cred->fsuid);
>>
>> to retrieve the integer that represents the uid.
>>
>> Please,
> sorry, I left this sentence incomplete, I was telling... Please, test
> your patches with current git trees :-). Thanks.

Thank you for reviewing the patches, I'll send a new version soon :)

--
Cheers,
Val

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Re: [PATCH v2 1/2] netfilter_queue: enable UID/GID socket info retrieval

[Valentina Giusti]

Hi,

On 12/20/2013 10:29 AM, Pablo Neira Ayuso wrote:
> On Fri, Dec 20, 2013 at 10:26:38AM +0100, Pablo Neira Ayuso wrote:
>> Hi,
>>
>> On Thu, Dec 19, 2013 at 12:03:26PM +0100, valentina.giusti@bmw-carit.de wrote:
>>> From: Valentina Giusti <valentina.giusti@oss.bmw-carit.de>
>>>
>>> Thanks to commits 41063e9 (ipv4: Early TCP socket demux) and 421b388 (udp: ipv4:
>>> Add udp early demux) it is now possible to parse UID and GID socket info
>>> also for incoming TCP and UDP connections. Having this info available, it
>>> is convenient to let NFQUEUE parse it in order to improve and refine the
>>> traffic analysis in userspace.
>>>
>>> Signed-off-by: Valentina Giusti <valentina.giusti@bmw-carit.de>
>>> ---
>>>   include/uapi/linux/netfilter/nfnetlink_queue.h |  5 ++++-
>>>   net/netfilter/nfnetlink_queue_core.c           | 31 ++++++++++++++++++++++++++
>>>   2 files changed, 35 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/include/uapi/linux/netfilter/nfnetlink_queue.h b/include/uapi/linux/netfilter/nfnetlink_queue.h
>>> index 0132bad..8dd819e 100644
>>> --- a/include/uapi/linux/netfilter/nfnetlink_queue.h
>>> +++ b/include/uapi/linux/netfilter/nfnetlink_queue.h
>>> @@ -47,6 +47,8 @@ enum nfqnl_attr_type {
>>>   	NFQA_CAP_LEN,			/* __u32 length of captured packet */
>>>   	NFQA_SKB_INFO,			/* __u32 skb meta information */
>>>   	NFQA_EXP,			/* nf_conntrack_netlink.h */
>>> +	NFQA_UID,			/* __u32 sk uid */
>>> +	NFQA_GID,			/* __u32 sk gid */
>>>   
>>>   	__NFQA_MAX
>>>   };
>>> @@ -99,7 +101,8 @@ enum nfqnl_attr_config {
>>>   #define NFQA_CFG_F_FAIL_OPEN			(1 << 0)
>>>   #define NFQA_CFG_F_CONNTRACK			(1 << 1)
>>>   #define NFQA_CFG_F_GSO				(1 << 2)
>>> -#define NFQA_CFG_F_MAX				(1 << 3)
>>> +#define NFQA_CFG_F_UID_GID			(1 << 3)
>>> +#define NFQA_CFG_F_MAX				(1 << 4)
>>>   
>>>   /* flags for NFQA_SKB_INFO */
>>>   /* packet appears to have wrong checksums, but they are ok */
>>> diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c
>>> index 21258cf..2cdef07 100644
>>> --- a/net/netfilter/nfnetlink_queue_core.c
>>> +++ b/net/netfilter/nfnetlink_queue_core.c
>>> @@ -297,6 +297,29 @@ nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
>>>   	return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
>>>   }
>>>   
>>> +static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
>>> +{
>>> +	const struct cred *cred;
>>> +
>>> +	if (sk && sk->sk_state != TCP_TIME_WAIT) {
>>> +		read_lock_bh(&sk->sk_callback_lock);
>>> +		if (sk->sk_socket && sk->sk_socket->file) {
>>> +			cred = sk->sk_socket->file->f_cred;
>>> +			if (nla_put_u32(skb, NFQA_UID, htonl(cred->fsuid)))
>> I'm hitting this compilation error here:
>>
>> net/netfilter/nfnetlink_queue_core.c: In function ‘nfqnl_put_sk_uidgid’:
>> net/netfilter/nfnetlink_queue_core.c:308:4: error: aggregate value used where an integer was expected
>>
>> It seems that in recent kernels you have to use:
>>
>>          from_kuid_munged(&init_user_ns, cred->fsuid);
>>
>> to retrieve the integer that represents the uid.
>>
>> Please,
> sorry, I left this sentence incomplete, I was telling... Please, test
> your patches with current git trees :-). Thanks.

Just to be on the safe side, I am testing my patches against the nf-next 
tree, branch master. Is that correct?

Thanks,
Val

Re: [PATCH v2 1/2] netfilter_queue: enable UID/GID socket info retrieval

[Florian Westphal]

Valentina Giusti <valentina.giusti@bmw-carit.de> wrote:
> Just to be on the safe side, I am testing my patches against the
> nf-next tree, branch master. Is that correct?

Yes, thats correct.