From 432490f9d455fb842d70219f22d9d2c812371676 Mon Sep 17 00:00:00 2001 From: Cyrill Gorcunov Date: Fri, 21 Oct 2016 13:03:44 +0300 Subject: [PATCH] net: ip, diag -- Add diag interface for raw sockets In criu we are actively using diag interface to collect sockets present in the system when dumping applications. And while for unix, tcp, udp[lite], packet, netlink it works as expected, the raw sockets do not have. Thus add it. v2: - add missing sock_put calls in raw_diag_dump_one (by eric.dumazet@) - implement @destroy for diag requests (by dsa@) v3: - add export of raw_abort for IPv6 (by dsa@) - pass net-admin flag into inet_sk_diag_fill due to changes in net-next branch (by dsa@) v4: - use @pad in struct inet_diag_req_v2 for raw socket protocol specification: raw module carries sockets which may have custom protocol passed from socket() syscall and sole @sdiag_protocol is not enough to match underlied ones - start reporting protocol specifed in socket() call when sockets are raw ones for the same reason: user space tools like ss may parse this attribute and use it for socket matching v5 (by eric.dumazet@): - use sock_hold in raw_sock_get instead of atomic_inc, we're holding (raw_v4_hashinfo|raw_v6_hashinfo)->lock when looking up so counter won't be zero here. v6: - use sdiag_raw_protocol() helper which will access @pad structure used for raw sockets protocol specification: we can't simply rename this member without breaking uapi v7: - sine sdiag_raw_protocol() helper is not suitable for uapi lets rather make an alias structure with proper names. __check_inet_diag_req_raw helper will catch if any of structure unintentionally changed. CC: David S. Miller CC: Eric Dumazet CC: David Ahern CC: Alexey Kuznetsov CC: James Morris CC: Hideaki YOSHIFUJI CC: Patrick McHardy CC: Andrey Vagin CC: Stephen Hemminger Signed-off-by: Cyrill Gorcunov Signed-off-by: David S. Miller --- include/net/raw.h | 6 + include/net/rawv6.h | 7 + include/uapi/linux/inet_diag.h | 17 +++ net/ipv4/Kconfig | 8 + net/ipv4/Makefile | 1 + net/ipv4/inet_diag.c | 9 ++ net/ipv4/raw.c | 21 ++- net/ipv4/raw_diag.c | 261 +++++++++++++++++++++++++++++++++ net/ipv6/raw.c | 7 +- 9 files changed, 333 insertions(+), 4 deletions(-) create mode 100644 net/ipv4/raw_diag.c diff --git a/include/net/raw.h b/include/net/raw.h index 3e789008394d32..57c33dd22ec4dc 100644 --- a/include/net/raw.h +++ b/include/net/raw.h @@ -23,6 +23,12 @@ extern struct proto raw_prot; +extern struct raw_hashinfo raw_v4_hashinfo; +struct sock *__raw_v4_lookup(struct net *net, struct sock *sk, + unsigned short num, __be32 raddr, + __be32 laddr, int dif); + +int raw_abort(struct sock *sk, int err); void raw_icmp_error(struct sk_buff *, int, u32); int raw_local_deliver(struct sk_buff *, int); diff --git a/include/net/rawv6.h b/include/net/rawv6.h index 87783dea0791c6..cbe4e9de189467 100644 --- a/include/net/rawv6.h +++ b/include/net/rawv6.h @@ -3,6 +3,13 @@ #include +extern struct raw_hashinfo raw_v6_hashinfo; +struct sock *__raw_v6_lookup(struct net *net, struct sock *sk, + unsigned short num, const struct in6_addr *loc_addr, + const struct in6_addr *rmt_addr, int dif); + +int raw_abort(struct sock *sk, int err); + void raw6_icmp_error(struct sk_buff *, int nexthdr, u8 type, u8 code, int inner_offset, __be32); bool raw6_local_deliver(struct sk_buff *, int); diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h index 509cd961068d5d..bbe201047df6c8 100644 --- a/include/uapi/linux/inet_diag.h +++ b/include/uapi/linux/inet_diag.h @@ -43,6 +43,23 @@ struct inet_diag_req_v2 { struct inet_diag_sockid id; }; +/* + * SOCK_RAW sockets require the underlied protocol to be + * additionally specified so we can use @pad member for + * this, but we can't rename it because userspace programs + * still may depend on this name. Instead lets use another + * structure definition as an alias for struct + * @inet_diag_req_v2. + */ +struct inet_diag_req_raw { + __u8 sdiag_family; + __u8 sdiag_protocol; + __u8 idiag_ext; + __u8 sdiag_raw_protocol; + __u32 idiag_states; + struct inet_diag_sockid id; +}; + enum { INET_DIAG_REQ_NONE, INET_DIAG_REQ_BYTECODE, diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig index 300b06888fdfd0..28e051a8e847c7 100644 --- a/net/ipv4/Kconfig +++ b/net/ipv4/Kconfig @@ -430,6 +430,14 @@ config INET_UDP_DIAG Support for UDP socket monitoring interface used by the ss tool. If unsure, say Y. +config INET_RAW_DIAG + tristate "RAW: socket monitoring interface" + depends on INET_DIAG && (IPV6 || IPV6=n) + default n + ---help--- + Support for RAW socket monitoring interface used by the ss tool. + If unsure, say Y. + config INET_DIAG_DESTROY bool "INET: allow privileged process to administratively close sockets" depends on INET_DIAG diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile index bc6a6c8b9bcd79..48af58a5686e3e 100644 --- a/net/ipv4/Makefile +++ b/net/ipv4/Makefile @@ -40,6 +40,7 @@ obj-$(CONFIG_NETFILTER) += netfilter.o netfilter/ obj-$(CONFIG_INET_DIAG) += inet_diag.o obj-$(CONFIG_INET_TCP_DIAG) += tcp_diag.o obj-$(CONFIG_INET_UDP_DIAG) += udp_diag.o +obj-$(CONFIG_INET_RAW_DIAG) += raw_diag.o obj-$(CONFIG_NET_TCPPROBE) += tcp_probe.o obj-$(CONFIG_TCP_CONG_BBR) += tcp_bbr.o obj-$(CONFIG_TCP_CONG_BIC) += tcp_bic.o diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index 0a1d4a896a261d..3b34024202d814 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -200,6 +200,15 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, if (sock_diag_put_meminfo(sk, skb, INET_DIAG_SKMEMINFO)) goto errout; + /* + * RAW sockets might have user-defined protocols assigned, + * so report the one supplied on socket creation. + */ + if (sk->sk_type == SOCK_RAW) { + if (nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol)) + goto errout; + } + if (!icsk) { handler->idiag_get_info(sk, r, NULL); goto out; diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index 90a85c95587244..03618ed035323f 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -89,9 +89,10 @@ struct raw_frag_vec { int hlen; }; -static struct raw_hashinfo raw_v4_hashinfo = { +struct raw_hashinfo raw_v4_hashinfo = { .lock = __RW_LOCK_UNLOCKED(raw_v4_hashinfo.lock), }; +EXPORT_SYMBOL_GPL(raw_v4_hashinfo); int raw_hash_sk(struct sock *sk) { @@ -120,7 +121,7 @@ void raw_unhash_sk(struct sock *sk) } EXPORT_SYMBOL_GPL(raw_unhash_sk); -static struct sock *__raw_v4_lookup(struct net *net, struct sock *sk, +struct sock *__raw_v4_lookup(struct net *net, struct sock *sk, unsigned short num, __be32 raddr, __be32 laddr, int dif) { sk_for_each_from(sk) { @@ -136,6 +137,7 @@ static struct sock *__raw_v4_lookup(struct net *net, struct sock *sk, found: return sk; } +EXPORT_SYMBOL_GPL(__raw_v4_lookup); /* * 0 - deliver @@ -912,6 +914,20 @@ static int compat_raw_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg } #endif +int raw_abort(struct sock *sk, int err) +{ + lock_sock(sk); + + sk->sk_err = err; + sk->sk_error_report(sk); + udp_disconnect(sk, 0); + + release_sock(sk); + + return 0; +} +EXPORT_SYMBOL_GPL(raw_abort); + struct proto raw_prot = { .name = "RAW", .owner = THIS_MODULE, @@ -937,6 +953,7 @@ struct proto raw_prot = { .compat_getsockopt = compat_raw_getsockopt, .compat_ioctl = compat_raw_ioctl, #endif + .diag_destroy = raw_abort, }; #ifdef CONFIG_PROC_FS diff --git a/net/ipv4/raw_diag.c b/net/ipv4/raw_diag.c new file mode 100644 index 00000000000000..ef3bea061b758f --- /dev/null +++ b/net/ipv4/raw_diag.c @@ -0,0 +1,261 @@ +#include + +#include +#include + +#include +#include + +#ifdef pr_fmt +# undef pr_fmt +#endif + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +static struct raw_hashinfo * +raw_get_hashinfo(const struct inet_diag_req_v2 *r) +{ + if (r->sdiag_family == AF_INET) { + return &raw_v4_hashinfo; +#if IS_ENABLED(CONFIG_IPV6) + } else if (r->sdiag_family == AF_INET6) { + return &raw_v6_hashinfo; +#endif + } else { + pr_warn_once("Unexpected inet family %d\n", + r->sdiag_family); + WARN_ON_ONCE(1); + return ERR_PTR(-EINVAL); + } +} + +/* + * Due to requirement of not breaking user API we can't simply + * rename @pad field in inet_diag_req_v2 structure, instead + * use helper to figure it out. + */ + +static struct sock *raw_lookup(struct net *net, struct sock *from, + const struct inet_diag_req_v2 *req) +{ + struct inet_diag_req_raw *r = (void *)req; + struct sock *sk = NULL; + + if (r->sdiag_family == AF_INET) + sk = __raw_v4_lookup(net, from, r->sdiag_raw_protocol, + r->id.idiag_dst[0], + r->id.idiag_src[0], + r->id.idiag_if); +#if IS_ENABLED(CONFIG_IPV6) + else + sk = __raw_v6_lookup(net, from, r->sdiag_raw_protocol, + (const struct in6_addr *)r->id.idiag_src, + (const struct in6_addr *)r->id.idiag_dst, + r->id.idiag_if); +#endif + return sk; +} + +static struct sock *raw_sock_get(struct net *net, const struct inet_diag_req_v2 *r) +{ + struct raw_hashinfo *hashinfo = raw_get_hashinfo(r); + struct sock *sk = NULL, *s; + int slot; + + if (IS_ERR(hashinfo)) + return ERR_CAST(hashinfo); + + read_lock(&hashinfo->lock); + for (slot = 0; slot < RAW_HTABLE_SIZE; slot++) { + sk_for_each(s, &hashinfo->ht[slot]) { + sk = raw_lookup(net, s, r); + if (sk) { + /* + * Grab it and keep until we fill + * diag meaage to be reported, so + * caller should call sock_put then. + * We can do that because we're keeping + * hashinfo->lock here. + */ + sock_hold(sk); + break; + } + } + } + read_unlock(&hashinfo->lock); + + return sk ? sk : ERR_PTR(-ENOENT); +} + +static int raw_diag_dump_one(struct sk_buff *in_skb, + const struct nlmsghdr *nlh, + const struct inet_diag_req_v2 *r) +{ + struct net *net = sock_net(in_skb->sk); + struct sk_buff *rep; + struct sock *sk; + int err; + + sk = raw_sock_get(net, r); + if (IS_ERR(sk)) + return PTR_ERR(sk); + + rep = nlmsg_new(sizeof(struct inet_diag_msg) + + sizeof(struct inet_diag_meminfo) + 64, + GFP_KERNEL); + if (!rep) { + sock_put(sk); + return -ENOMEM; + } + + err = inet_sk_diag_fill(sk, NULL, rep, r, + sk_user_ns(NETLINK_CB(in_skb).sk), + NETLINK_CB(in_skb).portid, + nlh->nlmsg_seq, 0, nlh, + netlink_net_capable(in_skb, CAP_NET_ADMIN)); + sock_put(sk); + + if (err < 0) { + kfree_skb(rep); + return err; + } + + err = netlink_unicast(net->diag_nlsk, rep, + NETLINK_CB(in_skb).portid, + MSG_DONTWAIT); + if (err > 0) + err = 0; + return err; +} + +static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, + struct netlink_callback *cb, + const struct inet_diag_req_v2 *r, + struct nlattr *bc, bool net_admin) +{ + if (!inet_diag_bc_sk(bc, sk)) + return 0; + + return inet_sk_diag_fill(sk, NULL, skb, r, + sk_user_ns(NETLINK_CB(cb->skb).sk), + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + cb->nlh, net_admin); +} + +static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, + const struct inet_diag_req_v2 *r, struct nlattr *bc) +{ + bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); + struct raw_hashinfo *hashinfo = raw_get_hashinfo(r); + struct net *net = sock_net(skb->sk); + int num, s_num, slot, s_slot; + struct sock *sk = NULL; + + if (IS_ERR(hashinfo)) + return; + + s_slot = cb->args[0]; + num = s_num = cb->args[1]; + + read_lock(&hashinfo->lock); + for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) { + num = 0; + + sk_for_each(sk, &hashinfo->ht[slot]) { + struct inet_sock *inet = inet_sk(sk); + + if (!net_eq(sock_net(sk), net)) + continue; + if (num < s_num) + goto next; + if (sk->sk_family != r->sdiag_family) + goto next; + if (r->id.idiag_sport != inet->inet_sport && + r->id.idiag_sport) + goto next; + if (r->id.idiag_dport != inet->inet_dport && + r->id.idiag_dport) + goto next; + if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) + goto out_unlock; +next: + num++; + } + } + +out_unlock: + read_unlock(&hashinfo->lock); + + cb->args[0] = slot; + cb->args[1] = num; +} + +static void raw_diag_get_info(struct sock *sk, struct inet_diag_msg *r, + void *info) +{ + r->idiag_rqueue = sk_rmem_alloc_get(sk); + r->idiag_wqueue = sk_wmem_alloc_get(sk); +} + +#ifdef CONFIG_INET_DIAG_DESTROY +static int raw_diag_destroy(struct sk_buff *in_skb, + const struct inet_diag_req_v2 *r) +{ + struct net *net = sock_net(in_skb->sk); + struct sock *sk; + + sk = raw_sock_get(net, r); + if (IS_ERR(sk)) + return PTR_ERR(sk); + return sock_diag_destroy(sk, ECONNABORTED); +} +#endif + +static const struct inet_diag_handler raw_diag_handler = { + .dump = raw_diag_dump, + .dump_one = raw_diag_dump_one, + .idiag_get_info = raw_diag_get_info, + .idiag_type = IPPROTO_RAW, + .idiag_info_size = 0, +#ifdef CONFIG_INET_DIAG_DESTROY + .destroy = raw_diag_destroy, +#endif +}; + +static void __always_unused __check_inet_diag_req_raw(void) +{ + /* + * Make sure the two structures are identical, + * except the @pad field. + */ +#define __offset_mismatch(m1, m2) \ + (offsetof(struct inet_diag_req_v2, m1) != \ + offsetof(struct inet_diag_req_raw, m2)) + + BUILD_BUG_ON(sizeof(struct inet_diag_req_v2) != + sizeof(struct inet_diag_req_raw)); + BUILD_BUG_ON(__offset_mismatch(sdiag_family, sdiag_family)); + BUILD_BUG_ON(__offset_mismatch(sdiag_protocol, sdiag_protocol)); + BUILD_BUG_ON(__offset_mismatch(idiag_ext, idiag_ext)); + BUILD_BUG_ON(__offset_mismatch(pad, sdiag_raw_protocol)); + BUILD_BUG_ON(__offset_mismatch(idiag_states, idiag_states)); + BUILD_BUG_ON(__offset_mismatch(id, id)); +#undef __offset_mismatch +} + +static int __init raw_diag_init(void) +{ + return inet_diag_register(&raw_diag_handler); +} + +static void __exit raw_diag_exit(void) +{ + inet_diag_unregister(&raw_diag_handler); +} + +module_init(raw_diag_init); +module_exit(raw_diag_exit); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-255 /* AF_INET - IPPROTO_RAW */); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10-255 /* AF_INET6 - IPPROTO_RAW */); diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index 54404f08efccaa..d7e8b955ade8f1 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -65,11 +65,12 @@ #define ICMPV6_HDRLEN 4 /* ICMPv6 header, RFC 4443 Section 2.1 */ -static struct raw_hashinfo raw_v6_hashinfo = { +struct raw_hashinfo raw_v6_hashinfo = { .lock = __RW_LOCK_UNLOCKED(raw_v6_hashinfo.lock), }; +EXPORT_SYMBOL_GPL(raw_v6_hashinfo); -static struct sock *__raw_v6_lookup(struct net *net, struct sock *sk, +struct sock *__raw_v6_lookup(struct net *net, struct sock *sk, unsigned short num, const struct in6_addr *loc_addr, const struct in6_addr *rmt_addr, int dif) { @@ -102,6 +103,7 @@ static struct sock *__raw_v6_lookup(struct net *net, struct sock *sk, found: return sk; } +EXPORT_SYMBOL_GPL(__raw_v6_lookup); /* * 0 - deliver @@ -1259,6 +1261,7 @@ struct proto rawv6_prot = { .compat_getsockopt = compat_rawv6_getsockopt, .compat_ioctl = compat_rawv6_ioctl, #endif + .diag_destroy = raw_abort, }; #ifdef CONFIG_PROC_FS