Commit 1330b6ef authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

skb: make drop reason booleanable 



We have a number of cases where function returns drop/no drop
decision as a boolean. Now that we want to report the reason
code as well we have to pass extra output arguments.

We can make the reason code evaluate correctly as bool.

I believe we're good to reorder the reasons as they are
reported to user space as strings.

Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 11633199

include/linux/skbuff.h

+1 −0
Original line number Diff line number Diff line
@@ -314,6 +314,7 @@ struct sk_buff; 
 * used to translate the reason to string.

 */

enum skb_drop_reason {

	SKB_NOT_DROPPED_YET = 0,

	SKB_DROP_REASON_NOT_SPECIFIED,	/* drop reason is not specified */

	SKB_DROP_REASON_NO_SOCKET,	/* socket not found */

	SKB_DROP_REASON_PKT_TOO_SMALL,	/* packet size is too small */

include/net/tcp.h

+11 −10
Original line number Diff line number Diff line
@@ -1674,8 +1674,9 @@ tcp_md5_do_lookup(const struct sock *sk, int l3index, 
		return NULL;

	return __tcp_md5_do_lookup(sk, l3index, addr, family);

}

bool tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb,

			  enum skb_drop_reason *reason,



enum skb_drop_reason

tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb,

		     const void *saddr, const void *daddr,

		     int family, int dif, int sdif);
@@ -1688,13 +1689,13 @@ tcp_md5_do_lookup(const struct sock *sk, int l3index, 
{

	return NULL;

}

static inline bool tcp_inbound_md5_hash(const struct sock *sk,

					const struct sk_buff *skb,

					enum skb_drop_reason *reason,



static inline enum skb_drop_reason

tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb,

		     const void *saddr, const void *daddr,

					int family, int dif, int sdif)

		     int family, int dif, int sdif);

{

	return false;

	return SKB_NOT_DROPPED_YET;

}

#define tcp_twsk_md5_key(twsk)	NULL

#endif

net/ipv4/tcp.c

+9 −12
Original line number Diff line number Diff line
@@ -4434,8 +4434,8 @@ int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, const struct tcp_md5sig_key *ke 
EXPORT_SYMBOL(tcp_md5_hash_key);



/* Called with rcu_read_lock() */

bool tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb,

			  enum skb_drop_reason *reason,

enum skb_drop_reason

tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb,

		     const void *saddr, const void *daddr,

		     int family, int dif, int sdif)

{
@@ -4464,18 +4464,16 @@ bool tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, 


	/* We've parsed the options - do we have a hash? */

	if (!hash_expected && !hash_location)

		return false;

		return SKB_NOT_DROPPED_YET;



	if (hash_expected && !hash_location) {

		*reason = SKB_DROP_REASON_TCP_MD5NOTFOUND;

		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);

		return true;

		return SKB_DROP_REASON_TCP_MD5NOTFOUND;

	}



	if (!hash_expected && hash_location) {

		*reason = SKB_DROP_REASON_TCP_MD5UNEXPECTED;

		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);

		return true;

		return SKB_DROP_REASON_TCP_MD5UNEXPECTED;

	}



	/* check the signature */
@@ -4483,7 +4481,6 @@ bool tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, 
						 NULL, skb);



	if (genhash || memcmp(hash_location, newhash, 16) != 0) {

		*reason = SKB_DROP_REASON_TCP_MD5FAILURE;

		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE);

		if (family == AF_INET) {

			net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s L3 index %d\n",
@@ -4497,9 +4494,9 @@ bool tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, 
					saddr, ntohs(th->source),

					daddr, ntohs(th->dest), l3index);

		}

		return true;

		return SKB_DROP_REASON_TCP_MD5FAILURE;

	}

	return false;

	return SKB_NOT_DROPPED_YET;

}

EXPORT_SYMBOL(tcp_inbound_md5_hash);

net/ipv4/tcp_ipv4.c

+7 −5
Original line number Diff line number Diff line
@@ -1965,9 +1965,10 @@ int tcp_v4_rcv(struct sk_buff *skb) 
		struct sock *nsk;



		sk = req->rsk_listener;

		if (unlikely(tcp_inbound_md5_hash(sk, skb, &drop_reason,

		drop_reason = tcp_inbound_md5_hash(sk, skb,

						   &iph->saddr, &iph->daddr,

						  AF_INET, dif, sdif))) {

						   AF_INET, dif, sdif);

		if (unlikely(drop_reason)) {

			sk_drops_add(sk, skb);

			reqsk_put(req);

			goto discard_it;
@@ -2041,8 +2042,9 @@ int tcp_v4_rcv(struct sk_buff *skb) 
		goto discard_and_relse;

	}



	if (tcp_inbound_md5_hash(sk, skb, &drop_reason, &iph->saddr,

				 &iph->daddr, AF_INET, dif, sdif))

	drop_reason = tcp_inbound_md5_hash(sk, skb, &iph->saddr,

					   &iph->daddr, AF_INET, dif, sdif);

	if (drop_reason)

		goto discard_and_relse;



	nf_reset_ct(skb);

net/ipv6/tcp_ipv6.c

+7 −4
Original line number Diff line number Diff line
@@ -1632,8 +1632,10 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb) 
		struct sock *nsk;



		sk = req->rsk_listener;

		if (tcp_inbound_md5_hash(sk, skb, &drop_reason, &hdr->saddr,

					 &hdr->daddr, AF_INET6, dif, sdif)) {

		drop_reason = tcp_inbound_md5_hash(sk, skb,

						   &hdr->saddr, &hdr->daddr,

						   AF_INET6, dif, sdif);

		if (drop_reason) {

			sk_drops_add(sk, skb);

			reqsk_put(req);

			goto discard_it;
@@ -1704,8 +1706,9 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb) 
		goto discard_and_relse;

	}



	if (tcp_inbound_md5_hash(sk, skb, &drop_reason, &hdr->saddr,

				 &hdr->daddr, AF_INET6, dif, sdif))

	drop_reason = tcp_inbound_md5_hash(sk, skb, &hdr->saddr, &hdr->daddr,

					   AF_INET6, dif, sdif);

	if (drop_reason)

		goto discard_and_relse;



	if (tcp_filter(sk, skb)) {