diff options
Diffstat (limited to 'net/ipv4/tcp_metrics.c')
| -rw-r--r-- | net/ipv4/tcp_metrics.c | 354 |
1 files changed, 341 insertions, 13 deletions
diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c index 0abe67bb4d3a..4c752a6e0bcd 100644 --- a/net/ipv4/tcp_metrics.c +++ b/net/ipv4/tcp_metrics.c @@ -8,6 +8,7 @@ #include <linux/init.h> #include <linux/tcp.h> #include <linux/hash.h> +#include <linux/tcp_metrics.h> #include <net/inet_connection_sock.h> #include <net/net_namespace.h> @@ -17,20 +18,10 @@ #include <net/ipv6.h> #include <net/dst.h> #include <net/tcp.h> +#include <net/genetlink.h> int sysctl_tcp_nometrics_save __read_mostly; -enum tcp_metric_index { - TCP_METRIC_RTT, - TCP_METRIC_RTTVAR, - TCP_METRIC_SSTHRESH, - TCP_METRIC_CWND, - TCP_METRIC_REORDERING, - - /* Always last. */ - TCP_METRIC_MAX, -}; - struct tcp_fastopen_metrics { u16 mss; u16 syn_loss:10; /* Recurring Fast Open SYN losses */ @@ -45,8 +36,10 @@ struct tcp_metrics_block { u32 tcpm_ts; u32 tcpm_ts_stamp; u32 tcpm_lock; - u32 tcpm_vals[TCP_METRIC_MAX]; + u32 tcpm_vals[TCP_METRIC_MAX + 1]; struct tcp_fastopen_metrics tcpm_fastopen; + + struct rcu_head rcu_head; }; static bool tcp_metric_locked(struct tcp_metrics_block *tm, @@ -690,6 +683,325 @@ void tcp_fastopen_cache_set(struct sock *sk, u16 mss, rcu_read_unlock(); } +static struct genl_family tcp_metrics_nl_family = { + .id = GENL_ID_GENERATE, + .hdrsize = 0, + .name = TCP_METRICS_GENL_NAME, + .version = TCP_METRICS_GENL_VERSION, + .maxattr = TCP_METRICS_ATTR_MAX, + .netnsok = true, +}; + +static struct nla_policy tcp_metrics_nl_policy[TCP_METRICS_ATTR_MAX + 1] = { + [TCP_METRICS_ATTR_ADDR_IPV4] = { .type = NLA_U32, }, + [TCP_METRICS_ATTR_ADDR_IPV6] = { .type = NLA_BINARY, + .len = sizeof(struct in6_addr), }, + /* Following attributes are not received for GET/DEL, + * we keep them for reference + */ +#if 0 + [TCP_METRICS_ATTR_AGE] = { .type = NLA_MSECS, }, + [TCP_METRICS_ATTR_TW_TSVAL] = { .type = NLA_U32, }, + [TCP_METRICS_ATTR_TW_TS_STAMP] = { .type = NLA_S32, }, + [TCP_METRICS_ATTR_VALS] = { .type = NLA_NESTED, }, + [TCP_METRICS_ATTR_FOPEN_MSS] = { .type = NLA_U16, }, + [TCP_METRICS_ATTR_FOPEN_SYN_DROPS] = { .type = NLA_U16, }, + [TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS] = { .type = NLA_MSECS, }, + [TCP_METRICS_ATTR_FOPEN_COOKIE] = { .type = NLA_BINARY, + .len = TCP_FASTOPEN_COOKIE_MAX, }, +#endif +}; + +/* Add attributes, caller cancels its header on failure */ +static int tcp_metrics_fill_info(struct sk_buff *msg, + struct tcp_metrics_block *tm) +{ + struct nlattr *nest; + int i; + + switch (tm->tcpm_addr.family) { + case AF_INET: + if (nla_put_be32(msg, TCP_METRICS_ATTR_ADDR_IPV4, + tm->tcpm_addr.addr.a4) < 0) + goto nla_put_failure; + break; + case AF_INET6: + if (nla_put(msg, TCP_METRICS_ATTR_ADDR_IPV6, 16, + tm->tcpm_addr.addr.a6) < 0) + goto nla_put_failure; + break; + default: + return -EAFNOSUPPORT; + } + + if (nla_put_msecs(msg, TCP_METRICS_ATTR_AGE, + jiffies - tm->tcpm_stamp) < 0) + goto nla_put_failure; + if (tm->tcpm_ts_stamp) { + if (nla_put_s32(msg, TCP_METRICS_ATTR_TW_TS_STAMP, + (s32) (get_seconds() - tm->tcpm_ts_stamp)) < 0) + goto nla_put_failure; + if (nla_put_u32(msg, TCP_METRICS_ATTR_TW_TSVAL, + tm->tcpm_ts) < 0) + goto nla_put_failure; + } + + { + int n = 0; + + nest = nla_nest_start(msg, TCP_METRICS_ATTR_VALS); + if (!nest) + goto nla_put_failure; + for (i = 0; i < TCP_METRIC_MAX + 1; i++) { + if (!tm->tcpm_vals[i]) + continue; + if (nla_put_u32(msg, i + 1, tm->tcpm_vals[i]) < 0) + goto nla_put_failure; + n++; + } + if (n) + nla_nest_end(msg, nest); + else + nla_nest_cancel(msg, nest); + } + + { + struct tcp_fastopen_metrics tfom_copy[1], *tfom; + unsigned int seq; + + do { + seq = read_seqbegin(&fastopen_seqlock); + tfom_copy[0] = tm->tcpm_fastopen; + } while (read_seqretry(&fastopen_seqlock, seq)); + + tfom = tfom_copy; + if (tfom->mss && + nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_MSS, + tfom->mss) < 0) + goto nla_put_failure; + if (tfom->syn_loss && + (nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROPS, + tfom->syn_loss) < 0 || + nla_put_msecs(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS, + jiffies - tfom->last_syn_loss) < 0)) + goto nla_put_failure; + if (tfom->cookie.len > 0 && + nla_put(msg, TCP_METRICS_ATTR_FOPEN_COOKIE, + tfom->cookie.len, tfom->cookie.val) < 0) + goto nla_put_failure; + } + + return 0; + +nla_put_failure: + return -EMSGSIZE; +} + +static int tcp_metrics_dump_info(struct sk_buff *skb, + struct netlink_callback *cb, + struct tcp_metrics_block *tm) +{ + void *hdr; + + hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &tcp_metrics_nl_family, NLM_F_MULTI, + TCP_METRICS_CMD_GET); + if (!hdr) + return -EMSGSIZE; + + if (tcp_metrics_fill_info(skb, tm) < 0) + goto nla_put_failure; + + return genlmsg_end(skb, hdr); + +nla_put_failure: + genlmsg_cancel(skb, hdr); + return -EMSGSIZE; +} + +static int tcp_metrics_nl_dump(struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct net *net = sock_net(skb->sk); + unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; + unsigned int row, s_row = cb->args[0]; + int s_col = cb->args[1], col = s_col; + + for (row = s_row; row < max_rows; row++, s_col = 0) { + struct tcp_metrics_block *tm; + struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash + row; + + rcu_read_lock(); + for (col = 0, tm = rcu_dereference(hb->chain); tm; + tm = rcu_dereference(tm->tcpm_next), col++) { + if (col < s_col) + continue; + if (tcp_metrics_dump_info(skb, cb, tm) < 0) { + rcu_read_unlock(); + goto done; + } + } + rcu_read_unlock(); + } + +done: + cb->args[0] = row; + cb->args[1] = col; + return skb->len; +} + +static int parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, + unsigned int *hash, int optional) +{ + struct nlattr *a; + + a = info->attrs[TCP_METRICS_ATTR_ADDR_IPV4]; + if (a) { + addr->family = AF_INET; + addr->addr.a4 = nla_get_be32(a); + *hash = (__force unsigned int) addr->addr.a4; + return 0; + } + a = info->attrs[TCP_METRICS_ATTR_ADDR_IPV6]; + if (a) { + if (nla_len(a) != sizeof(sizeof(struct in6_addr))) + return -EINVAL; + addr->family = AF_INET6; + memcpy(addr->addr.a6, nla_data(a), sizeof(addr->addr.a6)); + *hash = ipv6_addr_hash((struct in6_addr *) addr->addr.a6); + return 0; + } + return optional ? 1 : -EAFNOSUPPORT; +} + +static int tcp_metrics_nl_cmd_get(struct sk_buff *skb, struct genl_info *info) +{ + struct tcp_metrics_block *tm; + struct inetpeer_addr addr; + unsigned int hash; + struct sk_buff *msg; + struct net *net = genl_info_net(info); + void *reply; + int ret; + + ret = parse_nl_addr(info, &addr, &hash, 0); + if (ret < 0) + return ret; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + reply = genlmsg_put_reply(msg, info, &tcp_metrics_nl_family, 0, + info->genlhdr->cmd); + if (!reply) + goto nla_put_failure; + + hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); + ret = -ESRCH; + rcu_read_lock(); + for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; + tm = rcu_dereference(tm->tcpm_next)) { + if (addr_same(&tm->tcpm_addr, &addr)) { + ret = tcp_metrics_fill_info(msg, tm); + break; + } + } + rcu_read_unlock(); + if (ret < 0) + goto out_free; + + genlmsg_end(msg, reply); + return genlmsg_reply(msg, info); + +nla_put_failure: + ret = -EMSGSIZE; + +out_free: + nlmsg_free(msg); + return ret; +} + +#define deref_locked_genl(p) \ + rcu_dereference_protected(p, lockdep_genl_is_held() && \ + lockdep_is_held(&tcp_metrics_lock)) + +#define deref_genl(p) rcu_dereference_protected(p, lockdep_genl_is_held()) + +static int tcp_metrics_flush_all(struct net *net) +{ + unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; + struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash; + struct tcp_metrics_block *tm; + unsigned int row; + + for (row = 0; row < max_rows; row++, hb++) { + spin_lock_bh(&tcp_metrics_lock); + tm = deref_locked_genl(hb->chain); + if (tm) + hb->chain = NULL; + spin_unlock_bh(&tcp_metrics_lock); + while (tm) { + struct tcp_metrics_block *next; + + next = deref_genl(tm->tcpm_next); + kfree_rcu(tm, rcu_head); + tm = next; + } + } + return 0; +} + +static int tcp_metrics_nl_cmd_del(struct sk_buff *skb, struct genl_info *info) +{ + struct tcpm_hash_bucket *hb; + struct tcp_metrics_block *tm; + struct tcp_metrics_block __rcu **pp; + struct inetpeer_addr addr; + unsigned int hash; + struct net *net = genl_info_net(info); + int ret; + + ret = parse_nl_addr(info, &addr, &hash, 1); + if (ret < 0) + return ret; + if (ret > 0) + return tcp_metrics_flush_all(net); + + hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); + hb = net->ipv4.tcp_metrics_hash + hash; + pp = &hb->chain; + spin_lock_bh(&tcp_metrics_lock); + for (tm = deref_locked_genl(*pp); tm; + pp = &tm->tcpm_next, tm = deref_locked_genl(*pp)) { + if (addr_same(&tm->tcpm_addr, &addr)) { + *pp = tm->tcpm_next; + break; + } + } + spin_unlock_bh(&tcp_metrics_lock); + if (!tm) + return -ESRCH; + kfree_rcu(tm, rcu_head); + return 0; +} + +static struct genl_ops tcp_metrics_nl_ops[] = { + { + .cmd = TCP_METRICS_CMD_GET, + .doit = tcp_metrics_nl_cmd_get, + .dumpit = tcp_metrics_nl_dump, + .policy = tcp_metrics_nl_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = TCP_METRICS_CMD_DEL, + .doit = tcp_metrics_nl_cmd_del, + .policy = tcp_metrics_nl_policy, + .flags = GENL_ADMIN_PERM, + }, +}; + static unsigned int tcpmhash_entries; static int __init set_tcpmhash_entries(char *str) { @@ -753,5 +1065,21 @@ static __net_initdata struct pernet_operations tcp_net_metrics_ops = { void __init tcp_metrics_init(void) { - register_pernet_subsys(&tcp_net_metrics_ops); + int ret; + + ret = register_pernet_subsys(&tcp_net_metrics_ops); + if (ret < 0) + goto cleanup; + ret = genl_register_family_with_ops(&tcp_metrics_nl_family, + tcp_metrics_nl_ops, + ARRAY_SIZE(tcp_metrics_nl_ops)); + if (ret < 0) + goto cleanup_subsys; + return; + +cleanup_subsys: + unregister_pernet_subsys(&tcp_net_metrics_ops); + +cleanup: + return; } |