[PATCH v7 13/22] net/tcp: Add TCP-AO segments counters
From: Dmitry Safonov
Date: Wed Jun 14 2023 - 19:11:33 EST
Introduce segment counters that are useful for troubleshooting/debugging
as well as for writing tests.
Now there are global snmp counters as well as per-socket and per-key.
Co-developed-by: Francesco Ruggeri <fruggeri@xxxxxxxxxx>
Signed-off-by: Francesco Ruggeri <fruggeri@xxxxxxxxxx>
Co-developed-by: Salam Noureddine <noureddine@xxxxxxxxxx>
Signed-off-by: Salam Noureddine <noureddine@xxxxxxxxxx>
Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx>
---
include/net/dropreason-core.h | 15 +++++++++++----
include/net/tcp.h | 15 +++++++++++----
include/net/tcp_ao.h | 10 ++++++++++
include/uapi/linux/snmp.h | 4 ++++
include/uapi/linux/tcp.h | 8 +++++++-
net/ipv4/proc.c | 4 ++++
net/ipv4/tcp_ao.c | 33 +++++++++++++++++++++++++++++----
net/ipv4/tcp_ipv4.c | 2 +-
net/ipv6/tcp_ipv6.c | 4 ++--
9 files changed, 79 insertions(+), 16 deletions(-)
diff --git a/include/net/dropreason-core.h b/include/net/dropreason-core.h
index 0ff272d3b680..44ac4ebd8513 100644
--- a/include/net/dropreason-core.h
+++ b/include/net/dropreason-core.h
@@ -165,17 +165,24 @@ enum skb_drop_reason {
*/
SKB_DROP_REASON_TCP_MD5FAILURE,
/**
- * @SKB_DROP_REASON_TCP_AONOTFOUND: no TCP-AO hash and one was expected
+ * @SKB_DROP_REASON_TCP_AONOTFOUND: no TCP-AO hash and one was expected,
+ * corresponding to LINUX_MIB_TCPAOREQUIRED
*/
SKB_DROP_REASON_TCP_AONOTFOUND,
/**
* @SKB_DROP_REASON_TCP_AOUNEXPECTED: TCP-AO hash is present and it
- * was not expected.
+ * was not expected, corresponding to LINUX_MIB_TCPAOKEYNOTFOUND
*/
SKB_DROP_REASON_TCP_AOUNEXPECTED,
- /** @SKB_DROP_REASON_TCP_AOKEYNOTFOUND: TCP-AO key is unknown */
+ /**
+ * @SKB_DROP_REASON_TCP_AOKEYNOTFOUND: TCP-AO key is unknown,
+ * corresponding to LINUX_MIB_TCPAOKEYNOTFOUND
+ */
SKB_DROP_REASON_TCP_AOKEYNOTFOUND,
- /** @SKB_DROP_REASON_TCP_AOFAILURE: TCP-AO hash is wrong */
+ /**
+ * @SKB_DROP_REASON_TCP_AOFAILURE: TCP-AO hash is wrong,
+ * corresponding to LINUX_MIB_TCPAOBAD
+ */
SKB_DROP_REASON_TCP_AOFAILURE,
/**
* @SKB_DROP_REASON_SOCKET_BACKLOG: failed to add skb to socket backlog (
diff --git a/include/net/tcp.h b/include/net/tcp.h
index b3fa6aada5c7..d09f994f7562 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -2579,7 +2579,7 @@ static inline int tcp_parse_auth_options(const struct tcphdr *th,
}
static inline bool tcp_ao_required(struct sock *sk, const void *saddr,
- int family)
+ int family, bool stat_inc)
{
#ifdef CONFIG_TCP_AO
struct tcp_ao_info *ao_info;
@@ -2591,8 +2591,13 @@ static inline bool tcp_ao_required(struct sock *sk, const void *saddr,
return false;
ao_key = tcp_ao_do_lookup(sk, saddr, family, -1, -1, 0);
- if (ao_info->ao_required || ao_key)
+ if (ao_info->ao_required || ao_key) {
+ if (stat_inc) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOREQUIRED);
+ atomic64_inc(&ao_info->counters.ao_required);
+ }
return true;
+ }
#endif
return false;
}
@@ -2614,8 +2619,10 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req,
return SKB_DROP_REASON_TCP_AUTH_HDR;
if (req) {
- if (tcp_rsk_used_ao(req) != !!aoh)
+ if (tcp_rsk_used_ao(req) != !!aoh) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD);
return SKB_DROP_REASON_TCP_AOFAILURE;
+ }
}
/* sdif set, means packet ingressed via a device
@@ -2630,7 +2637,7 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req,
* the last key is impossible to remove, so there's
* always at least one current_key.
*/
- if (tcp_ao_required(sk, saddr, family))
+ if (tcp_ao_required(sk, saddr, family, true))
return SKB_DROP_REASON_TCP_AONOTFOUND;
if (unlikely(tcp_md5_do_lookup(sk, l3index, saddr, family))) {
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h
index 880eeee4a6b9..9930e56e35be 100644
--- a/include/net/tcp_ao.h
+++ b/include/net/tcp_ao.h
@@ -20,6 +20,13 @@ struct tcp_ao_hdr {
u8 rnext_keyid;
};
+struct tcp_ao_counters {
+ atomic64_t pkt_good;
+ atomic64_t pkt_bad;
+ atomic64_t key_not_found;
+ atomic64_t ao_required;
+};
+
struct tcp_ao_key {
struct hlist_node node;
union tcp_ao_addr addr;
@@ -35,6 +42,8 @@ struct tcp_ao_key {
u8 maclen;
u8 digest_size;
struct rcu_head rcu;
+ atomic64_t pkt_good;
+ atomic64_t pkt_bad;
u8 traffic_keys[];
};
@@ -83,6 +92,7 @@ struct tcp_ao_info {
*/
struct tcp_ao_key *current_key;
struct tcp_ao_key *rnext_key;
+ struct tcp_ao_counters counters;
u32 ao_required :1,
__unused :31;
__be32 lisn;
diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h
index 26f33a4c253d..06ddf4cd295c 100644
--- a/include/uapi/linux/snmp.h
+++ b/include/uapi/linux/snmp.h
@@ -296,6 +296,10 @@ enum
LINUX_MIB_TCPMIGRATEREQSUCCESS, /* TCPMigrateReqSuccess */
LINUX_MIB_TCPMIGRATEREQFAILURE, /* TCPMigrateReqFailure */
LINUX_MIB_TCPPLBREHASH, /* TCPPLBRehash */
+ LINUX_MIB_TCPAOREQUIRED, /* TCPAORequired */
+ LINUX_MIB_TCPAOBAD, /* TCPAOBad */
+ LINUX_MIB_TCPAOKEYNOTFOUND, /* TCPAOKeyNotFound */
+ LINUX_MIB_TCPAOGOOD, /* TCPAOGood */
__LINUX_MIB_MAX
};
diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h
index 250e0ce2cc38..3fe0612ec59a 100644
--- a/include/uapi/linux/tcp.h
+++ b/include/uapi/linux/tcp.h
@@ -391,9 +391,15 @@ struct tcp_ao_info_opt { /* setsockopt(TCP_AO_INFO) */
__u32 set_current :1, /* corresponding ::current_key */
set_rnext :1, /* corresponding ::rnext */
ao_required :1, /* don't accept non-AO connects */
- reserved :29; /* must be 0 */
+ set_counters :1, /* set/clear ::pkt_* counters */
+ reserved :28; /* must be 0 */
+ __u16 reserved2; /* padding, must be 0 */
__u8 current_key; /* KeyID to set as Current_key */
__u8 rnext; /* KeyID to set as Rnext_key */
+ __u64 pkt_good; /* verified segments */
+ __u64 pkt_bad; /* failed verification */
+ __u64 pkt_key_not_found; /* could not find a key to verify */
+ __u64 pkt_ao_required; /* segments missing TCP-AO sign */
} __attribute__((aligned(8)));
/* setsockopt(fd, IPPROTO_TCP, TCP_ZEROCOPY_RECEIVE, ...) */
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index eaf1d3113b62..3f643cd29cfe 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -298,6 +298,10 @@ static const struct snmp_mib snmp4_net_list[] = {
SNMP_MIB_ITEM("TCPMigrateReqSuccess", LINUX_MIB_TCPMIGRATEREQSUCCESS),
SNMP_MIB_ITEM("TCPMigrateReqFailure", LINUX_MIB_TCPMIGRATEREQFAILURE),
SNMP_MIB_ITEM("TCPPLBRehash", LINUX_MIB_TCPPLBREHASH),
+ SNMP_MIB_ITEM("TCPAORequired", LINUX_MIB_TCPAOREQUIRED),
+ SNMP_MIB_ITEM("TCPAOBad", LINUX_MIB_TCPAOBAD),
+ SNMP_MIB_ITEM("TCPAOKeyNotFound", LINUX_MIB_TCPAOKEYNOTFOUND),
+ SNMP_MIB_ITEM("TCPAOGood", LINUX_MIB_TCPAOGOOD),
SNMP_MIB_SENTINEL
};
diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c
index 3f405bf1fd82..4c618d339009 100644
--- a/net/ipv4/tcp_ao.c
+++ b/net/ipv4/tcp_ao.c
@@ -194,6 +194,8 @@ static struct tcp_ao_key *tcp_ao_copy_key(struct sock *sk,
*new_key = *key;
INIT_HLIST_NODE(&new_key->node);
tcp_sigpool_get(new_key->tcp_sigpool_id);
+ atomic64_set(&new_key->pkt_good, 0);
+ atomic64_set(&new_key->pkt_bad, 0);
return new_key;
}
@@ -735,14 +737,25 @@ tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb,
u8 maclen = aoh->length - sizeof(struct tcp_ao_hdr);
const struct tcphdr *th = tcp_hdr(skb);
- if (maclen != tcp_ao_maclen(key))
+ if (maclen != tcp_ao_maclen(key)) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD);
+ atomic64_inc(&info->counters.pkt_bad);
+ atomic64_inc(&key->pkt_bad);
return SKB_DROP_REASON_TCP_AOFAILURE;
+ }
/* XXX: make it per-AF callback? */
tcp_ao_hash_skb(family, newhash, key, sk, skb, traffic_key,
(phash - (u8 *)th), sne);
- if (memcmp(phash, newhash, maclen))
+ if (memcmp(phash, newhash, maclen)) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD);
+ atomic64_inc(&info->counters.pkt_bad);
+ atomic64_inc(&key->pkt_bad);
return SKB_DROP_REASON_TCP_AOFAILURE;
+ }
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOGOOD);
+ atomic64_inc(&info->counters.pkt_good);
+ atomic64_inc(&key->pkt_good);
return SKB_NOT_DROPPED_YET;
}
@@ -761,8 +774,10 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
u32 sne = 0;
info = rcu_dereference(tcp_sk(sk)->ao_info);
- if (!info)
+ if (!info) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND);
return SKB_DROP_REASON_TCP_AOUNEXPECTED;
+ }
if (unlikely(th->syn)) {
sisn = th->seq;
@@ -857,6 +872,8 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
traffic_key, phash, sne);
key_not_found:
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND);
+ atomic64_inc(&info->counters.key_not_found);
return SKB_DROP_REASON_TCP_AOKEYNOTFOUND;
}
EXPORT_SYMBOL_GPL(tcp_inbound_ao_hash);
@@ -1422,6 +1439,8 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family,
key->keyflags = cmd.keyflags;
key->sndid = cmd.sndid;
key->rcvid = cmd.rcvid;
+ atomic64_set(&key->pkt_good, 0);
+ atomic64_set(&key->pkt_bad, 0);
ret = tcp_ao_parse_crypto(&cmd, key);
if (ret < 0)
@@ -1635,7 +1654,7 @@ static int tcp_ao_info_cmd(struct sock *sk, unsigned short int family,
return -EINVAL;
}
- if (cmd.reserved != 0)
+ if (cmd.reserved != 0 || cmd.reserved2 != 0)
return -EINVAL;
ao_info = setsockopt_ao_info(sk);
@@ -1670,6 +1689,12 @@ static int tcp_ao_info_cmd(struct sock *sk, unsigned short int family,
goto out;
}
}
+ if (cmd.set_counters) {
+ atomic64_set(&ao_info->counters.pkt_good, cmd.pkt_good);
+ atomic64_set(&ao_info->counters.pkt_bad, cmd.pkt_bad);
+ atomic64_set(&ao_info->counters.key_not_found, cmd.pkt_key_not_found);
+ atomic64_set(&ao_info->counters.ao_required, cmd.pkt_ao_required);
+ }
ao_info->ao_required = cmd.ao_required;
if (new_current)
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 1a0c2f1485fa..9799ab8e7e00 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1523,7 +1523,7 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, int optname,
/* Don't allow keys for peers that have a matching TCP-AO key.
* See the comment in tcp_ao_add_cmd()
*/
- if (tcp_ao_required(sk, addr, AF_INET))
+ if (tcp_ao_required(sk, addr, AF_INET, false))
return -EKEYREJECTED;
return tcp_md5_do_add(sk, addr, AF_INET, prefixlen, l3index, flags,
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index cd9b3714d8a6..0c45c0020ff9 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -664,7 +664,7 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname,
/* Don't allow keys for peers that have a matching TCP-AO key.
* See the comment in tcp_ao_add_cmd()
*/
- if (tcp_ao_required(sk, addr, AF_INET))
+ if (tcp_ao_required(sk, addr, AF_INET, false))
return -EKEYREJECTED;
return tcp_md5_do_add(sk, addr,
AF_INET, prefixlen, l3index, flags,
@@ -676,7 +676,7 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname,
/* Don't allow keys for peers that have a matching TCP-AO key.
* See the comment in tcp_ao_add_cmd()
*/
- if (tcp_ao_required(sk, addr, AF_INET6))
+ if (tcp_ao_required(sk, addr, AF_INET6, false))
return -EKEYREJECTED;
return tcp_md5_do_add(sk, addr, AF_INET6, prefixlen, l3index, flags,
--
2.40.0