From 61723b393292f1e4ea27f8d123384d50b176c29d Mon Sep 17 00:00:00 2001 From: Davide Caratti Date: Fri, 30 Aug 2019 12:25:48 +0200 Subject: tcp: ulp: add functions to dump ulp-specific information currently, only getsockopt(TCP_ULP) can be invoked to know if a ULP is on top of a TCP socket. Extend idiag_get_aux() and idiag_get_aux_size(), introduced by commit b37e88407c1d ("inet_diag: allow protocols to provide additional data"), to report the ULP name and other information that can be made available by the ULP through optional functions. Users having CAP_NET_ADMIN privileges will then be able to retrieve this information through inet_diag_handler, if they specify INET_DIAG_INFO in the request. Signed-off-by: Davide Caratti Signed-off-by: David S. Miller --- include/net/tcp.h | 3 +++ include/uapi/linux/inet_diag.h | 8 +++++++ net/ipv4/tcp_diag.c | 52 +++++++++++++++++++++++++++++++++++++++++- 3 files changed, 62 insertions(+), 1 deletion(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 77fe87f7a992..c9a3f9688223 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2122,6 +2122,9 @@ struct tcp_ulp_ops { void (*update)(struct sock *sk, struct proto *p); /* cleanup ulp */ void (*release)(struct sock *sk); + /* diagnostic */ + int (*get_info)(const struct sock *sk, struct sk_buff *skb); + size_t (*get_info_size)(const struct sock *sk); char name[TCP_ULP_NAME_MAX]; struct module *owner; diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h index e8baca85bac6..e2c6273274f3 100644 --- a/include/uapi/linux/inet_diag.h +++ b/include/uapi/linux/inet_diag.h @@ -153,11 +153,19 @@ enum { INET_DIAG_BBRINFO, /* request as INET_DIAG_VEGASINFO */ INET_DIAG_CLASS_ID, /* request as INET_DIAG_TCLASS */ INET_DIAG_MD5SIG, + INET_DIAG_ULP_INFO, __INET_DIAG_MAX, }; #define INET_DIAG_MAX (__INET_DIAG_MAX - 1) +enum { + INET_ULP_INFO_UNSPEC, + INET_ULP_INFO_NAME, + __INET_ULP_INFO_MAX, +}; +#define INET_ULP_INFO_MAX (__INET_ULP_INFO_MAX - 1) + /* INET_DIAG_MEM */ struct inet_diag_meminfo { diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c index a3a386236d93..babc156deabb 100644 --- a/net/ipv4/tcp_diag.c +++ b/net/ipv4/tcp_diag.c @@ -81,13 +81,42 @@ static int tcp_diag_put_md5sig(struct sk_buff *skb, } #endif +static int tcp_diag_put_ulp(struct sk_buff *skb, struct sock *sk, + const struct tcp_ulp_ops *ulp_ops) +{ + struct nlattr *nest; + int err; + + nest = nla_nest_start_noflag(skb, INET_DIAG_ULP_INFO); + if (!nest) + return -EMSGSIZE; + + err = nla_put_string(skb, INET_ULP_INFO_NAME, ulp_ops->name); + if (err) + goto nla_failure; + + if (ulp_ops->get_info) + err = ulp_ops->get_info(sk, skb); + if (err) + goto nla_failure; + + nla_nest_end(skb, nest); + return 0; + +nla_failure: + nla_nest_cancel(skb, nest); + return err; +} + static int tcp_diag_get_aux(struct sock *sk, bool net_admin, struct sk_buff *skb) { + struct inet_connection_sock *icsk = inet_csk(sk); + int err = 0; + #ifdef CONFIG_TCP_MD5SIG if (net_admin) { struct tcp_md5sig_info *md5sig; - int err = 0; rcu_read_lock(); md5sig = rcu_dereference(tcp_sk(sk)->md5sig_info); @@ -99,11 +128,21 @@ static int tcp_diag_get_aux(struct sock *sk, bool net_admin, } #endif + if (net_admin) { + const struct tcp_ulp_ops *ulp_ops; + + ulp_ops = icsk->icsk_ulp_ops; + if (ulp_ops) + err = tcp_diag_put_ulp(skb, sk, ulp_ops); + if (err) + return err; + } return 0; } static size_t tcp_diag_get_aux_size(struct sock *sk, bool net_admin) { + struct inet_connection_sock *icsk = inet_csk(sk); size_t size = 0; #ifdef CONFIG_TCP_MD5SIG @@ -124,6 +163,17 @@ static size_t tcp_diag_get_aux_size(struct sock *sk, bool net_admin) } #endif + if (net_admin) { + const struct tcp_ulp_ops *ulp_ops; + + ulp_ops = icsk->icsk_ulp_ops; + if (ulp_ops) { + size += nla_total_size(0) + + nla_total_size(TCP_ULP_NAME_MAX); + if (ulp_ops->get_info_size) + size += ulp_ops->get_info_size(sk); + } + } return size; } -- cgit v1.2.3-59-g8ed1b