Signed-off-by: Leonard Crestez <cdleonard@xxxxxxxxx> --- Documentation/networking/tcp_authopt.rst | 10 +++ net/ipv4/tcp_authopt.c | 100 ++++++++++++++++++++++- 2 files changed, 109 insertions(+), 1 deletion(-) diff --git a/Documentation/networking/tcp_authopt.rst b/Documentation/networking/tcp_authopt.rst index 6520c6d02755..eaf389f99139 100644 --- a/Documentation/networking/tcp_authopt.rst +++ b/Documentation/networking/tcp_authopt.rst @@ -69,10 +69,20 @@ The rnextkeyid value sent on the wire is usually the recv_id of the current key used for sending. If the TCP_AUTHOPT_LOCK_RNEXTKEY flag is set in `tcp_authopt.flags` the value of `tcp_authopt.send_rnextkeyid` is send instead. This can be used to implement smooth rollover: the peer will switch its keyid to the received rnextkeyid when it is available. +Proc interface +-------------- + +The ``/proc/net/tcp_authopt`` file contains a tab-separated table of keys. The +first line contains column names. The number of columns might increase in the +future if more matching criteria are added. Here is an example of the table:: + + flags send_id recv_id alg addr l3index + 0x44 0 0 1 10.10.2.2/31 0 + ABI Reference ============= .. kernel-doc:: include/uapi/linux/tcp.h :identifiers: tcp_authopt tcp_authopt_flag tcp_authopt_key tcp_authopt_key_flag tcp_authopt_alg diff --git a/net/ipv4/tcp_authopt.c b/net/ipv4/tcp_authopt.c index 64bcb2a38472..22ce68c933a9 100644 --- a/net/ipv4/tcp_authopt.c +++ b/net/ipv4/tcp_authopt.c @@ -5,10 +5,11 @@ #include <net/ipv6.h> #include <net/tcp.h> #include <linux/kref.h> #include <crypto/hash.h> #include <linux/inetdevice.h> +#include <linux/proc_fs.h> /* This is mainly intended to protect against local privilege escalations through * a rarely used feature so it is deliberately not namespaced. */ int sysctl_tcp_authopt; @@ -1661,26 +1662,123 @@ int __tcp_authopt_inbound_check(struct sock *sk, struct sk_buff *skb, return 1; } EXPORT_SYMBOL(__tcp_authopt_inbound_check); +struct tcp_authopt_iter_state { + struct seq_net_private p; +}; + +static struct tcp_authopt_key_info *tcp_authopt_get_key_index(struct netns_tcp_authopt *net, + int index) +{ + struct tcp_authopt_key_info *key; + + hlist_for_each_entry(key, &net->head, node) { + if (--index < 0) + return key; + } + + return NULL; +} + +static void *tcp_authopt_seq_start(struct seq_file *seq, loff_t *pos) + __acquires(RCU) +{ + struct netns_tcp_authopt *net = &seq_file_net(seq)->tcp_authopt; + + rcu_read_lock(); + if (*pos == 0) + return SEQ_START_TOKEN; + else + return tcp_authopt_get_key_index(net, *pos - 1); +} + +static void tcp_authopt_seq_stop(struct seq_file *seq, void *v) + __releases(RCU) +{ + rcu_read_unlock(); +} + +static void *tcp_authopt_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + struct netns_tcp_authopt *net = &seq_file_net(seq)->tcp_authopt; + void *ret; + + ret = tcp_authopt_get_key_index(net, *pos); + ++*pos; + + return ret; +} + +static int tcp_authopt_seq_show(struct seq_file *seq, void *v) +{ + struct tcp_authopt_key_info *key = v; + + /* FIXME: Document somewhere */ + /* Key is deliberately inaccessible */ + if (v == SEQ_START_TOKEN) { + seq_puts(seq, "flags\tsend_id\trecv_id\talg\taddr\tl3index\n"); + return 0; + } + + seq_printf(seq, "0x%x\t%d\t%d\t%d", + key->flags, key->send_id, key->recv_id, (int)key->alg_id); + if (key->flags & TCP_AUTHOPT_KEY_ADDR_BIND) { + if (key->addr.ss_family == AF_INET6) + seq_printf(seq, "\t%pI6", &((struct sockaddr_in6 *)&key->addr)->sin6_addr); + else + seq_printf(seq, "\t%pI4", &((struct sockaddr_in *)&key->addr)->sin_addr); + if (key->flags & TCP_AUTHOPT_KEY_PREFIXLEN) + seq_printf(seq, "/%d", key->prefixlen); + } else { + seq_puts(seq, "\t*"); + } + seq_printf(seq, "\t%d", key->l3index); + seq_puts(seq, "\n"); + + return 0; +} + +static const struct seq_operations tcp_authopt_seq_ops = { + .start = tcp_authopt_seq_start, + .next = tcp_authopt_seq_next, + .stop = tcp_authopt_seq_stop, + .show = tcp_authopt_seq_show, +}; + +static int __net_init tcp_authopt_proc_init_net(struct net *net) +{ + if (!proc_create_net("tcp_authopt", 0400, net->proc_net, + &tcp_authopt_seq_ops, + sizeof(struct tcp_authopt_iter_state))) + return -ENOMEM; + return 0; +} + +static void __net_exit tcp_authopt_proc_exit_net(struct net *net) +{ + remove_proc_entry("tcp_authopt", net->proc_net); +} + static int tcp_authopt_init_net(struct net *full_net) { struct netns_tcp_authopt *net = &full_net->tcp_authopt; mutex_init(&net->mutex); INIT_HLIST_HEAD(&net->head); - return 0; + return tcp_authopt_proc_init_net(full_net); } static void tcp_authopt_exit_net(struct net *full_net) { struct netns_tcp_authopt *net = &full_net->tcp_authopt; struct tcp_authopt_key_info *key; struct hlist_node *n; + tcp_authopt_proc_exit_net(full_net); mutex_lock(&net->mutex); hlist_for_each_entry_safe(key, n, &net->head, node) { hlist_del_rcu(&key->node); tcp_authopt_key_put(key); -- 2.25.1