Add TCP_AO_REPAIR setsockopt(), getsockopt(). They let a user to repair
TCP-AO ISNs/SNEs. Also let the user hack around when (tp->repair) is on
and add ao_info on a socket in any supported state.
As SNEs now can be read/written at any moment, use
WRITE_ONCE()/READ_ONCE() to set/read them.
Signed-off-by: Dmitry Safonov <[email protected]>
Acked-by: David Ahern <[email protected]>
---
include/net/tcp_ao.h | 14 +++++++
include/uapi/linux/tcp.h | 8 ++++
net/ipv4/tcp.c | 24 +++++++----
net/ipv4/tcp_ao.c | 90 ++++++++++++++++++++++++++++++++++++++--
4 files changed, 125 insertions(+), 11 deletions(-)
diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h
index da04efa1aaa5..dfdd980c5d87 100644
--- a/include/net/tcp_ao.h
+++ b/include/net/tcp_ao.h
@@ -197,6 +197,8 @@ void tcp_ao_time_wait(struct tcp_timewait_sock *tcptw, struct tcp_sock *tp);
bool tcp_ao_ignore_icmp(const struct sock *sk, int type, int code);
int tcp_ao_get_mkts(struct sock *sk, sockptr_t optval, sockptr_t optlen);
int tcp_ao_get_sock_info(struct sock *sk, sockptr_t optval, sockptr_t optlen);
+int tcp_ao_get_repair(struct sock *sk, sockptr_t optval, sockptr_t optlen);
+int tcp_ao_set_repair(struct sock *sk, sockptr_t optval, unsigned int optlen);
enum skb_drop_reason tcp_inbound_ao_hash(struct sock *sk,
const struct sk_buff *skb, unsigned short int family,
const struct request_sock *req, int l3index,
@@ -315,6 +317,18 @@ static inline int tcp_ao_get_sock_info(struct sock *sk, sockptr_t optval, sockpt
{
return -ENOPROTOOPT;
}
+
+static inline int tcp_ao_get_repair(struct sock *sk,
+ sockptr_t optval, sockptr_t optlen)
+{
+ return -ENOPROTOOPT;
+}
+
+static inline int tcp_ao_set_repair(struct sock *sk,
+ sockptr_t optval, unsigned int optlen)
+{
+ return -ENOPROTOOPT;
+}
#endif
#if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AO)
diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h
index 25d62ecb9532..3440f8bbab46 100644
--- a/include/uapi/linux/tcp.h
+++ b/include/uapi/linux/tcp.h
@@ -133,6 +133,7 @@ enum {
#define TCP_AO_DEL_KEY 39 /* Delete MKT */
#define TCP_AO_INFO 40 /* Set/list TCP-AO per-socket options */
#define TCP_AO_GET_KEYS 41 /* List MKT(s) */
+#define TCP_AO_REPAIR 42 /* Get/Set SNEs and ISNs */
#define TCP_REPAIR_ON 1
#define TCP_REPAIR_OFF 0
@@ -457,6 +458,13 @@ struct tcp_ao_getsockopt { /* getsockopt(TCP_AO_GET_KEYS) */
__u64 pkt_bad; /* out: segments that failed verification */
} __attribute__((aligned(8)));
+struct tcp_ao_repair { /* {s,g}etsockopt(TCP_AO_REPAIR) */
+ __be32 snt_isn;
+ __be32 rcv_isn;
+ __u32 snd_sne;
+ __u32 rcv_sne;
+} __attribute__((aligned(8)));
+
/* setsockopt(fd, IPPROTO_TCP, TCP_ZEROCOPY_RECEIVE, ...) */
#define TCP_RECEIVE_ZEROCOPY_FLAG_TLB_CLEAN_HINT 0x1
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index d745086bf1a8..7263cd609cfb 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3597,20 +3597,28 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname,
__tcp_sock_set_quickack(sk, val);
break;
+ case TCP_AO_REPAIR:
+ err = tcp_ao_set_repair(sk, optval, optlen);
+ break;
#ifdef CONFIG_TCP_AO
case TCP_AO_ADD_KEY:
case TCP_AO_DEL_KEY:
case TCP_AO_INFO: {
/* If this is the first TCP-AO setsockopt() on the socket,
- * sk_state has to be LISTEN or CLOSE
+ * sk_state has to be LISTEN or CLOSE. Allow TCP_REPAIR
+ * in any state.
*/
- if (((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) ||
- rcu_dereference_protected(tcp_sk(sk)->ao_info,
+ if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
+ goto ao_parse;
+ if (rcu_dereference_protected(tcp_sk(sk)->ao_info,
lockdep_sock_is_held(sk)))
- err = tp->af_specific->ao_parse(sk, optname, optval,
- optlen);
- else
- err = -EISCONN;
+ goto ao_parse;
+ if (tp->repair)
+ goto ao_parse;
+ err = -EISCONN;
+ break;
+ao_parse:
+ err = tp->af_specific->ao_parse(sk, optname, optval, optlen);
break;
}
#endif
@@ -4277,6 +4285,8 @@ int do_tcp_getsockopt(struct sock *sk, int level,
return err;
}
#endif
+ case TCP_AO_REPAIR:
+ return tcp_ao_get_repair(sk, optval, optlen);
case TCP_AO_GET_KEYS:
case TCP_AO_INFO: {
int err;
diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c
index 522d3c84ac96..8a5c2824a9b4 100644
--- a/net/ipv4/tcp_ao.c
+++ b/net/ipv4/tcp_ao.c
@@ -1439,6 +1439,16 @@ static struct tcp_ao_info *setsockopt_ao_info(struct sock *sk)
return ERR_PTR(-ESOCKTNOSUPPORT);
}
+static struct tcp_ao_info *getsockopt_ao_info(struct sock *sk)
+{
+ if (sk_fullsock(sk))
+ return rcu_dereference(tcp_sk(sk)->ao_info);
+ else if (sk->sk_state == TCP_TIME_WAIT)
+ return rcu_dereference(tcp_twsk(sk)->ao_info);
+
+ return ERR_PTR(-ESOCKTNOSUPPORT);
+}
+
#define TCP_AO_KEYF_ALL (TCP_AO_KEYF_IFINDEX | TCP_AO_KEYF_EXCLUDE_OPT)
#define TCP_AO_GET_KEYF_VALID (TCP_AO_KEYF_IFINDEX)
@@ -1620,11 +1630,13 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family,
if (ret < 0)
goto err_free_sock;
- /* Change this condition if we allow adding keys in states
- * like close_wait, syn_sent or fin_wait...
- */
- if (sk->sk_state == TCP_ESTABLISHED)
+ if (!((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))) {
tcp_ao_cache_traffic_keys(sk, ao_info, key);
+ if (first) {
+ ao_info->current_key = key;
+ ao_info->rnext_key = key;
+ }
+ }
tcp_ao_link_mkt(ao_info, key);
if (first) {
@@ -1875,6 +1887,8 @@ static int tcp_ao_info_cmd(struct sock *sk, unsigned short int family,
if (IS_ERR(ao_info))
return PTR_ERR(ao_info);
if (!ao_info) {
+ if (!((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)))
+ return -EINVAL;
ao_info = tcp_ao_alloc_info(GFP_KERNEL);
if (!ao_info)
return -ENOMEM;
@@ -2257,3 +2271,71 @@ int tcp_ao_get_sock_info(struct sock *sk, sockptr_t optval, sockptr_t optlen)
return 0;
}
+int tcp_ao_set_repair(struct sock *sk, sockptr_t optval, unsigned int optlen)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct tcp_ao_repair cmd;
+ struct tcp_ao_key *key;
+ struct tcp_ao_info *ao;
+ int err;
+
+ if (optlen < sizeof(cmd))
+ return -EINVAL;
+
+ err = copy_struct_from_sockptr(&cmd, sizeof(cmd), optval, optlen);
+ if (err)
+ return err;
+
+ if (!tp->repair)
+ return -EPERM;
+
+ ao = setsockopt_ao_info(sk);
+ if (IS_ERR(ao))
+ return PTR_ERR(ao);
+ if (!ao)
+ return -ENOENT;
+
+ WRITE_ONCE(ao->lisn, cmd.snt_isn);
+ WRITE_ONCE(ao->risn, cmd.rcv_isn);
+ WRITE_ONCE(ao->snd_sne, cmd.snd_sne);
+ WRITE_ONCE(ao->rcv_sne, cmd.rcv_sne);
+
+ hlist_for_each_entry_rcu(key, &ao->head, node)
+ tcp_ao_cache_traffic_keys(sk, ao, key);
+
+ return 0;
+}
+
+int tcp_ao_get_repair(struct sock *sk, sockptr_t optval, sockptr_t optlen)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct tcp_ao_repair opt;
+ struct tcp_ao_info *ao;
+ int len;
+
+ if (copy_from_sockptr(&len, optlen, sizeof(int)))
+ return -EFAULT;
+
+ if (len <= 0)
+ return -EINVAL;
+
+ if (!tp->repair)
+ return -EPERM;
+
+ rcu_read_lock();
+ ao = getsockopt_ao_info(sk);
+ if (IS_ERR_OR_NULL(ao)) {
+ rcu_read_unlock();
+ return ao ? PTR_ERR(ao) : -ENOENT;
+ }
+
+ opt.snt_isn = ao->lisn;
+ opt.rcv_isn = ao->risn;
+ opt.snd_sne = READ_ONCE(ao->snd_sne);
+ opt.rcv_sne = READ_ONCE(ao->rcv_sne);
+ rcu_read_unlock();
+
+ if (copy_to_sockptr(optval, &opt, min_t(int, len, sizeof(opt))))
+ return -EFAULT;
+ return 0;
+}
--
2.41.0