diff options
Diffstat (limited to 'net/ipv4/inet_diag.c')
| -rw-r--r-- | net/ipv4/inet_diag.c | 1124 |
1 files changed, 1124 insertions, 0 deletions
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c new file mode 100644 index 000000000..34b77aa87 --- /dev/null +++ b/net/ipv4/inet_diag.c @@ -0,0 +1,1124 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * inet_diag.c Module for monitoring INET transport protocols sockets. + * + * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/fcntl.h> +#include <linux/random.h> +#include <linux/slab.h> +#include <linux/cache.h> +#include <linux/init.h> +#include <linux/time.h> + +#include <net/icmp.h> +#include <net/tcp.h> +#include <net/ipv6.h> +#include <net/inet_common.h> +#include <net/inet_connection_sock.h> +#include <net/bpf_sk_storage.h> +#include <net/netlink.h> + +#include <linux/inet.h> +#include <linux/stddef.h> + +#include <linux/inet_diag.h> +#include <linux/sock_diag.h> + +static const struct inet_diag_handler __rcu **inet_diag_table; + +struct inet_diag_entry { + const __be32 *saddr; + const __be32 *daddr; + u16 sport; + u16 dport; + u16 family; + u16 userlocks; + u32 ifindex; + u32 mark; +#ifdef CONFIG_SOCK_CGROUP_DATA + u64 cgroup_id; +#endif +}; + +static const struct inet_diag_handler *inet_diag_lock_handler(int proto) +{ + const struct inet_diag_handler *handler; + + if (proto < 0 || proto >= IPPROTO_MAX) + return NULL; + + if (!READ_ONCE(inet_diag_table[proto])) + sock_load_diag_module(AF_INET, proto); + + rcu_read_lock(); + handler = rcu_dereference(inet_diag_table[proto]); + if (handler && !try_module_get(handler->owner)) + handler = NULL; + rcu_read_unlock(); + + return handler; +} + +static void inet_diag_unlock_handler(const struct inet_diag_handler *handler) +{ + module_put(handler->owner); +} + +void inet_diag_msg_common_fill(struct inet_diag_msg *r, struct sock *sk) +{ + r->idiag_family = READ_ONCE(sk->sk_family); + + r->id.idiag_sport = htons(READ_ONCE(sk->sk_num)); + r->id.idiag_dport = READ_ONCE(sk->sk_dport); + r->id.idiag_if = READ_ONCE(sk->sk_bound_dev_if); + sock_diag_save_cookie(sk, r->id.idiag_cookie); + +#if IS_ENABLED(CONFIG_IPV6) + if (r->idiag_family == AF_INET6) { + data_race(*(struct in6_addr *)r->id.idiag_src = sk->sk_v6_rcv_saddr); + data_race(*(struct in6_addr *)r->id.idiag_dst = sk->sk_v6_daddr); + } else +#endif + { + memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src)); + memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst)); + + r->id.idiag_src[0] = READ_ONCE(sk->sk_rcv_saddr); + r->id.idiag_dst[0] = READ_ONCE(sk->sk_daddr); + } +} +EXPORT_SYMBOL_GPL(inet_diag_msg_common_fill); + +int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb, + struct inet_diag_msg *r, int ext, + struct user_namespace *user_ns, + bool net_admin) +{ + const struct inet_sock *inet = inet_sk(sk); + struct inet_diag_sockopt inet_sockopt; + + if (nla_put_u8(skb, INET_DIAG_SHUTDOWN, sk->sk_shutdown)) + goto errout; + + /* IPv6 dual-stack sockets use inet->tos for IPv4 connections, + * hence this needs to be included regardless of socket family. + */ + if (ext & (1 << (INET_DIAG_TOS - 1))) + if (nla_put_u8(skb, INET_DIAG_TOS, READ_ONCE(inet->tos)) < 0) + goto errout; + +#if IS_ENABLED(CONFIG_IPV6) + if (r->idiag_family == AF_INET6) { + if (ext & (1 << (INET_DIAG_TCLASS - 1))) + if (nla_put_u8(skb, INET_DIAG_TCLASS, + inet6_sk(sk)->tclass) < 0) + goto errout; + + if (((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) && + nla_put_u8(skb, INET_DIAG_SKV6ONLY, ipv6_only_sock(sk))) + goto errout; + } +#endif + + if (net_admin && nla_put_u32(skb, INET_DIAG_MARK, READ_ONCE(sk->sk_mark))) + goto errout; + + if (ext & (1 << (INET_DIAG_CLASS_ID - 1)) || + ext & (1 << (INET_DIAG_TCLASS - 1))) { + u32 classid = 0; + +#ifdef CONFIG_CGROUP_NET_CLASSID + classid = sock_cgroup_classid(&sk->sk_cgrp_data); +#endif + /* Fallback to socket priority if class id isn't set. + * Classful qdiscs use it as direct reference to class. + * For cgroup2 classid is always zero. + */ + if (!classid) + classid = READ_ONCE(sk->sk_priority); + + if (nla_put_u32(skb, INET_DIAG_CLASS_ID, classid)) + goto errout; + } + +#ifdef CONFIG_SOCK_CGROUP_DATA + if (nla_put_u64_64bit(skb, INET_DIAG_CGROUP_ID, + cgroup_id(sock_cgroup_ptr(&sk->sk_cgrp_data)), + INET_DIAG_PAD)) + goto errout; +#endif + + r->idiag_uid = from_kuid_munged(user_ns, sk_uid(sk)); + r->idiag_inode = sock_i_ino(sk); + + memset(&inet_sockopt, 0, sizeof(inet_sockopt)); + inet_sockopt.recverr = inet_test_bit(RECVERR, sk); + inet_sockopt.is_icsk = inet_test_bit(IS_ICSK, sk); + inet_sockopt.freebind = inet_test_bit(FREEBIND, sk); + inet_sockopt.hdrincl = inet_test_bit(HDRINCL, sk); + inet_sockopt.mc_loop = inet_test_bit(MC_LOOP, sk); + inet_sockopt.transparent = inet_test_bit(TRANSPARENT, sk); + inet_sockopt.mc_all = inet_test_bit(MC_ALL, sk); + inet_sockopt.nodefrag = inet_test_bit(NODEFRAG, sk); + inet_sockopt.bind_address_no_port = inet_test_bit(BIND_ADDRESS_NO_PORT, sk); + inet_sockopt.recverr_rfc4884 = inet_test_bit(RECVERR_RFC4884, sk); + inet_sockopt.defer_connect = inet_test_bit(DEFER_CONNECT, sk); + if (nla_put(skb, INET_DIAG_SOCKOPT, sizeof(inet_sockopt), + &inet_sockopt)) + goto errout; + + return 0; +errout: + return 1; +} +EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill); + +static int inet_diag_parse_attrs(const struct nlmsghdr *nlh, int hdrlen, + struct nlattr **req_nlas) +{ + struct nlattr *nla; + int remaining; + + nlmsg_for_each_attr(nla, nlh, hdrlen, remaining) { + int type = nla_type(nla); + + if (type == INET_DIAG_REQ_PROTOCOL && nla_len(nla) != sizeof(u32)) + return -EINVAL; + + if (type < __INET_DIAG_REQ_MAX) + req_nlas[type] = nla; + } + return 0; +} + +static int inet_diag_get_protocol(const struct inet_diag_req_v2 *req, + const struct inet_diag_dump_data *data) +{ + if (data->req_nlas[INET_DIAG_REQ_PROTOCOL]) + return nla_get_u32(data->req_nlas[INET_DIAG_REQ_PROTOCOL]); + return req->sdiag_protocol; +} + +#define MAX_DUMP_ALLOC_SIZE (KMALLOC_MAX_SIZE - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) + +int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, + struct sk_buff *skb, struct netlink_callback *cb, + const struct inet_diag_req_v2 *req, + u16 nlmsg_flags, bool net_admin) +{ + const struct tcp_congestion_ops *ca_ops; + const struct inet_diag_handler *handler; + struct inet_diag_dump_data *cb_data; + int ext = req->idiag_ext; + struct inet_diag_msg *r; + struct nlmsghdr *nlh; + struct nlattr *attr; + void *info = NULL; + u8 icsk_pending; + int protocol; + + cb_data = cb->data; + protocol = inet_diag_get_protocol(req, cb_data); + + /* inet_diag_lock_handler() made sure inet_diag_table[] is stable. */ + handler = rcu_dereference_protected(inet_diag_table[protocol], 1); + DEBUG_NET_WARN_ON_ONCE(!handler); + if (!handler) + return -ENXIO; + + nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags); + if (!nlh) + return -EMSGSIZE; + + r = nlmsg_data(nlh); + BUG_ON(!sk_fullsock(sk)); + + inet_diag_msg_common_fill(r, sk); + r->idiag_state = sk->sk_state; + r->idiag_timer = IDIAG_TIMER_OFF; + r->idiag_retrans = 0; + r->idiag_expires = 0; + + if (inet_diag_msg_attrs_fill(sk, skb, r, ext, + sk_user_ns(NETLINK_CB(cb->skb).sk), + net_admin)) + goto errout; + + if (ext & (1 << (INET_DIAG_MEMINFO - 1))) { + struct inet_diag_meminfo minfo = { + .idiag_rmem = sk_rmem_alloc_get(sk), + .idiag_wmem = READ_ONCE(sk->sk_wmem_queued), + .idiag_fmem = READ_ONCE(sk->sk_forward_alloc), + .idiag_tmem = sk_wmem_alloc_get(sk), + }; + + if (nla_put(skb, INET_DIAG_MEMINFO, sizeof(minfo), &minfo) < 0) + goto errout; + } + + if (ext & (1 << (INET_DIAG_SKMEMINFO - 1))) + 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; + } + + icsk_pending = smp_load_acquire(&icsk->icsk_pending); + if (icsk_pending == ICSK_TIME_RETRANS || + icsk_pending == ICSK_TIME_REO_TIMEOUT || + icsk_pending == ICSK_TIME_LOSS_PROBE) { + r->idiag_timer = IDIAG_TIMER_ON; + r->idiag_retrans = READ_ONCE(icsk->icsk_retransmits); + r->idiag_expires = + jiffies_delta_to_msecs(tcp_timeout_expires(sk) - jiffies); + } else if (icsk_pending == ICSK_TIME_PROBE0) { + r->idiag_timer = IDIAG_TIMER_PROBE0; + r->idiag_retrans = READ_ONCE(icsk->icsk_probes_out); + r->idiag_expires = + jiffies_delta_to_msecs(tcp_timeout_expires(sk) - jiffies); + } else if (timer_pending(&icsk->icsk_keepalive_timer)) { + r->idiag_timer = IDIAG_TIMER_KEEPALIVE; + r->idiag_retrans = READ_ONCE(icsk->icsk_probes_out); + r->idiag_expires = + jiffies_delta_to_msecs(icsk->icsk_keepalive_timer.expires - jiffies); + } else if ((READ_ONCE(icsk->icsk_ack.pending) & ICSK_ACK_TIMER) && + timer_pending(&icsk->icsk_delack_timer)) { + r->idiag_timer = IDIAG_TIMER_DELACK; + r->idiag_expires = + jiffies_delta_to_msecs(icsk_delack_timeout(icsk) - jiffies); + } + + if ((ext & (1 << (INET_DIAG_INFO - 1))) && handler->idiag_info_size) { + attr = nla_reserve_64bit(skb, INET_DIAG_INFO, + handler->idiag_info_size, + INET_DIAG_PAD); + if (!attr) + goto errout; + + info = nla_data(attr); + } + + if (ext & (1 << (INET_DIAG_CONG - 1))) { + int err = 0; + + rcu_read_lock(); + ca_ops = READ_ONCE(icsk->icsk_ca_ops); + if (ca_ops) + err = nla_put_string(skb, INET_DIAG_CONG, ca_ops->name); + rcu_read_unlock(); + if (err < 0) + goto errout; + } + + handler->idiag_get_info(sk, r, info); + + if (ext & (1 << (INET_DIAG_INFO - 1)) && handler->idiag_get_aux) + if (handler->idiag_get_aux(sk, net_admin, skb) < 0) + goto errout; + + if (sk->sk_state < TCP_TIME_WAIT) { + union tcp_cc_info info; + size_t sz = 0; + int attr; + + rcu_read_lock(); + ca_ops = READ_ONCE(icsk->icsk_ca_ops); + if (ca_ops && ca_ops->get_info) + sz = ca_ops->get_info(sk, ext, &attr, &info); + rcu_read_unlock(); + if (sz && nla_put(skb, attr, sz, &info) < 0) + goto errout; + } + + /* Keep it at the end for potential retry with a larger skb, + * or else do best-effort fitting, which is only done for the + * first_nlmsg. + */ + if (cb_data->bpf_stg_diag) { + bool first_nlmsg = ((unsigned char *)nlh == skb->data); + unsigned int prev_min_dump_alloc; + unsigned int total_nla_size = 0; + unsigned int msg_len; + int err; + + msg_len = skb_tail_pointer(skb) - (unsigned char *)nlh; + err = bpf_sk_storage_diag_put(cb_data->bpf_stg_diag, sk, skb, + INET_DIAG_SK_BPF_STORAGES, + &total_nla_size); + + if (!err) + goto out; + + total_nla_size += msg_len; + prev_min_dump_alloc = cb->min_dump_alloc; + if (total_nla_size > prev_min_dump_alloc) + cb->min_dump_alloc = min_t(u32, total_nla_size, + MAX_DUMP_ALLOC_SIZE); + + if (!first_nlmsg) + goto errout; + + if (cb->min_dump_alloc > prev_min_dump_alloc) + /* Retry with pskb_expand_head() with + * __GFP_DIRECT_RECLAIM + */ + goto errout; + + WARN_ON_ONCE(total_nla_size <= prev_min_dump_alloc); + + /* Send what we have for this sk + * and move on to the next sk in the following + * dump() + */ + } + +out: + nlmsg_end(skb, nlh); + return 0; + +errout: + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; +} +EXPORT_SYMBOL_GPL(inet_sk_diag_fill); + +static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb, + const struct nlmsghdr *nlh, + int hdrlen, + const struct inet_diag_req_v2 *req) +{ + const struct inet_diag_handler *handler; + struct inet_diag_dump_data dump_data; + int err, protocol; + + memset(&dump_data, 0, sizeof(dump_data)); + err = inet_diag_parse_attrs(nlh, hdrlen, dump_data.req_nlas); + if (err) + return err; + + protocol = inet_diag_get_protocol(req, &dump_data); + + handler = inet_diag_lock_handler(protocol); + if (!handler) + return -ENOENT; + + if (cmd == SOCK_DIAG_BY_FAMILY) { + struct netlink_callback cb = { + .nlh = nlh, + .skb = in_skb, + .data = &dump_data, + }; + err = handler->dump_one(&cb, req); + } else if (cmd == SOCK_DESTROY && handler->destroy) { + err = handler->destroy(in_skb, req); + } else { + err = -EOPNOTSUPP; + } + inet_diag_unlock_handler(handler); + + return err; +} + +static int bitstring_match(const __be32 *a1, const __be32 *a2, int bits) +{ + int words = bits >> 5; + + bits &= 0x1f; + + if (words) { + if (memcmp(a1, a2, words << 2)) + return 0; + } + if (bits) { + __be32 w1, w2; + __be32 mask; + + w1 = a1[words]; + w2 = a2[words]; + + mask = htonl((0xffffffff) << (32 - bits)); + + if ((w1 ^ w2) & mask) + return 0; + } + + return 1; +} + +static int inet_diag_bc_run(const struct nlattr *_bc, + const struct inet_diag_entry *entry) +{ + const void *bc = nla_data(_bc); + int len = nla_len(_bc); + + while (len > 0) { + int yes = 1; + const struct inet_diag_bc_op *op = bc; + + switch (op->code) { + case INET_DIAG_BC_NOP: + break; + case INET_DIAG_BC_JMP: + yes = 0; + break; + case INET_DIAG_BC_S_EQ: + yes = entry->sport == op[1].no; + break; + case INET_DIAG_BC_S_GE: + yes = entry->sport >= op[1].no; + break; + case INET_DIAG_BC_S_LE: + yes = entry->sport <= op[1].no; + break; + case INET_DIAG_BC_D_EQ: + yes = entry->dport == op[1].no; + break; + case INET_DIAG_BC_D_GE: + yes = entry->dport >= op[1].no; + break; + case INET_DIAG_BC_D_LE: + yes = entry->dport <= op[1].no; + break; + case INET_DIAG_BC_AUTO: + yes = !(entry->userlocks & SOCK_BINDPORT_LOCK); + break; + case INET_DIAG_BC_S_COND: + case INET_DIAG_BC_D_COND: { + const struct inet_diag_hostcond *cond; + const __be32 *addr; + + cond = (const struct inet_diag_hostcond *)(op + 1); + if (cond->port != -1 && + cond->port != (op->code == INET_DIAG_BC_S_COND ? + entry->sport : entry->dport)) { + yes = 0; + break; + } + + if (op->code == INET_DIAG_BC_S_COND) + addr = entry->saddr; + else + addr = entry->daddr; + + if (cond->family != AF_UNSPEC && + cond->family != entry->family) { + if (entry->family == AF_INET6 && + cond->family == AF_INET) { + if (addr[0] == 0 && addr[1] == 0 && + addr[2] == htonl(0xffff) && + bitstring_match(addr + 3, + cond->addr, + cond->prefix_len)) + break; + } + yes = 0; + break; + } + + if (cond->prefix_len == 0) + break; + if (bitstring_match(addr, cond->addr, + cond->prefix_len)) + break; + yes = 0; + break; + } + case INET_DIAG_BC_DEV_COND: { + u32 ifindex; + + ifindex = *((const u32 *)(op + 1)); + if (ifindex != entry->ifindex) + yes = 0; + break; + } + case INET_DIAG_BC_MARK_COND: { + struct inet_diag_markcond *cond; + + cond = (struct inet_diag_markcond *)(op + 1); + if ((entry->mark & cond->mask) != cond->mark) + yes = 0; + break; + } +#ifdef CONFIG_SOCK_CGROUP_DATA + case INET_DIAG_BC_CGROUP_COND: { + u64 cgroup_id; + + cgroup_id = get_unaligned((const u64 *)(op + 1)); + if (cgroup_id != entry->cgroup_id) + yes = 0; + break; + } +#endif + } + + if (yes) { + len -= op->yes; + bc += op->yes; + } else { + len -= op->no; + bc += op->no; + } + } + return len == 0; +} + +/* This helper is available for all sockets (ESTABLISH, TIMEWAIT, SYN_RECV) + */ +static void entry_fill_addrs(struct inet_diag_entry *entry, + const struct sock *sk) +{ +#if IS_ENABLED(CONFIG_IPV6) + if (entry->family == AF_INET6) { + entry->saddr = sk->sk_v6_rcv_saddr.s6_addr32; + entry->daddr = sk->sk_v6_daddr.s6_addr32; + } else +#endif + { + entry->saddr = &sk->sk_rcv_saddr; + entry->daddr = &sk->sk_daddr; + } +} + +int inet_diag_bc_sk(const struct inet_diag_dump_data *cb_data, struct sock *sk) +{ + const struct nlattr *bc = cb_data->inet_diag_nla_bc; + const struct inet_sock *inet = inet_sk(sk); + struct inet_diag_entry entry; + + if (!bc) + return 1; + + entry.family = READ_ONCE(sk->sk_family); + entry_fill_addrs(&entry, sk); + entry.sport = READ_ONCE(inet->inet_num); + entry.dport = ntohs(READ_ONCE(inet->inet_dport)); + entry.ifindex = READ_ONCE(sk->sk_bound_dev_if); + if (cb_data->userlocks_needed) + entry.userlocks = sk_fullsock(sk) ? READ_ONCE(sk->sk_userlocks) : 0; + if (cb_data->mark_needed) { + if (sk_fullsock(sk)) + entry.mark = READ_ONCE(sk->sk_mark); + else if (sk->sk_state == TCP_NEW_SYN_RECV) + entry.mark = inet_rsk(inet_reqsk(sk))->ir_mark; + else if (sk->sk_state == TCP_TIME_WAIT) + entry.mark = inet_twsk(sk)->tw_mark; + else + entry.mark = 0; + } +#ifdef CONFIG_SOCK_CGROUP_DATA + if (cb_data->cgroup_needed) + entry.cgroup_id = sk_fullsock(sk) ? + cgroup_id(sock_cgroup_ptr(&sk->sk_cgrp_data)) : 0; +#endif + + return inet_diag_bc_run(bc, &entry); +} +EXPORT_SYMBOL_GPL(inet_diag_bc_sk); + +static int valid_cc(const void *bc, int len, int cc) +{ + while (len >= 0) { + const struct inet_diag_bc_op *op = bc; + + if (cc > len) + return 0; + if (cc == len) + return 1; + if (op->yes < 4 || op->yes & 3) + return 0; + len -= op->yes; + bc += op->yes; + } + return 0; +} + +/* data is u32 ifindex */ +static bool valid_devcond(const struct inet_diag_bc_op *op, int len, + int *min_len) +{ + /* Check ifindex space. */ + *min_len += sizeof(u32); + if (len < *min_len) + return false; + + return true; +} +/* Validate an inet_diag_hostcond. */ +static bool valid_hostcond(const struct inet_diag_bc_op *op, int len, + int *min_len) +{ + struct inet_diag_hostcond *cond; + int addr_len; + + /* Check hostcond space. */ + *min_len += sizeof(struct inet_diag_hostcond); + if (len < *min_len) + return false; + cond = (struct inet_diag_hostcond *)(op + 1); + + /* Check address family and address length. */ + switch (cond->family) { + case AF_UNSPEC: + addr_len = 0; + break; + case AF_INET: + addr_len = sizeof(struct in_addr); + break; + case AF_INET6: + addr_len = sizeof(struct in6_addr); + break; + default: + return false; + } + *min_len += addr_len; + if (len < *min_len) + return false; + + /* Check prefix length (in bits) vs address length (in bytes). */ + if (cond->prefix_len > 8 * addr_len) + return false; + + return true; +} + +/* Validate a port comparison operator. */ +static bool valid_port_comparison(const struct inet_diag_bc_op *op, + int len, int *min_len) +{ + /* Port comparisons put the port in a follow-on inet_diag_bc_op. */ + *min_len += sizeof(struct inet_diag_bc_op); + if (len < *min_len) + return false; + return true; +} + +static bool valid_markcond(const struct inet_diag_bc_op *op, int len, + int *min_len) +{ + *min_len += sizeof(struct inet_diag_markcond); + return len >= *min_len; +} + +#ifdef CONFIG_SOCK_CGROUP_DATA +static bool valid_cgroupcond(const struct inet_diag_bc_op *op, int len, + int *min_len) +{ + *min_len += sizeof(u64); + return len >= *min_len; +} +#endif + +static int inet_diag_bc_audit(struct inet_diag_dump_data *cb_data, + const struct sk_buff *skb) +{ + const struct nlattr *attr = cb_data->inet_diag_nla_bc; + const void *bytecode, *bc; + int bytecode_len, len; + bool net_admin; + + if (!attr) + return 0; + + if (nla_len(attr) < sizeof(struct inet_diag_bc_op)) + return -EINVAL; + + net_admin = netlink_net_capable(skb, CAP_NET_ADMIN); + bytecode = bc = nla_data(attr); + len = bytecode_len = nla_len(attr); + + while (len > 0) { + int min_len = sizeof(struct inet_diag_bc_op); + const struct inet_diag_bc_op *op = bc; + + switch (op->code) { + case INET_DIAG_BC_S_COND: + case INET_DIAG_BC_D_COND: + if (!valid_hostcond(bc, len, &min_len)) + return -EINVAL; + break; + case INET_DIAG_BC_DEV_COND: + if (!valid_devcond(bc, len, &min_len)) + return -EINVAL; + break; + case INET_DIAG_BC_S_EQ: + case INET_DIAG_BC_S_GE: + case INET_DIAG_BC_S_LE: + case INET_DIAG_BC_D_EQ: + case INET_DIAG_BC_D_GE: + case INET_DIAG_BC_D_LE: + if (!valid_port_comparison(bc, len, &min_len)) + return -EINVAL; + break; + case INET_DIAG_BC_MARK_COND: + if (!net_admin) + return -EPERM; + if (!valid_markcond(bc, len, &min_len)) + return -EINVAL; + cb_data->mark_needed = true; + break; +#ifdef CONFIG_SOCK_CGROUP_DATA + case INET_DIAG_BC_CGROUP_COND: + if (!valid_cgroupcond(bc, len, &min_len)) + return -EINVAL; + cb_data->cgroup_needed = true; + break; +#endif + case INET_DIAG_BC_AUTO: + cb_data->userlocks_needed = true; + fallthrough; + case INET_DIAG_BC_JMP: + case INET_DIAG_BC_NOP: + break; + default: + return -EINVAL; + } + + if (op->code != INET_DIAG_BC_NOP) { + if (op->no < min_len || op->no > len + 4 || op->no & 3) + return -EINVAL; + if (op->no < len && + !valid_cc(bytecode, bytecode_len, len - op->no)) + return -EINVAL; + } + + if (op->yes < min_len || op->yes > len + 4 || op->yes & 3) + return -EINVAL; + bc += op->yes; + len -= op->yes; + } + return len == 0 ? 0 : -EINVAL; +} + +static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, + const struct inet_diag_req_v2 *r) +{ + struct inet_diag_dump_data *cb_data = cb->data; + const struct inet_diag_handler *handler; + u32 prev_min_dump_alloc; + int protocol, err = 0; + + protocol = inet_diag_get_protocol(r, cb_data); + +again: + prev_min_dump_alloc = cb->min_dump_alloc; + handler = inet_diag_lock_handler(protocol); + if (handler) { + handler->dump(skb, cb, r); + inet_diag_unlock_handler(handler); + } else { + err = -ENOENT; + } + /* The skb is not large enough to fit one sk info and + * inet_sk_diag_fill() has requested for a larger skb. + */ + if (!skb->len && cb->min_dump_alloc > prev_min_dump_alloc) { + err = pskb_expand_head(skb, 0, cb->min_dump_alloc, GFP_KERNEL); + if (!err) + goto again; + } + + return err ? : skb->len; +} + +static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh)); +} + +static int __inet_diag_dump_start(struct netlink_callback *cb, int hdrlen) +{ + const struct nlmsghdr *nlh = cb->nlh; + struct inet_diag_dump_data *cb_data; + struct sk_buff *skb = cb->skb; + struct nlattr *nla; + int err; + + cb_data = kzalloc_obj(*cb_data); + if (!cb_data) + return -ENOMEM; + + err = inet_diag_parse_attrs(nlh, hdrlen, cb_data->req_nlas); + if (err) { + kfree(cb_data); + return err; + } + err = inet_diag_bc_audit(cb_data, skb); + if (err) { + kfree(cb_data); + return err; + } + + nla = cb_data->inet_diag_nla_bpf_stgs; + if (nla) { + struct bpf_sk_storage_diag *bpf_stg_diag; + + bpf_stg_diag = bpf_sk_storage_diag_alloc(nla); + if (IS_ERR(bpf_stg_diag)) { + kfree(cb_data); + return PTR_ERR(bpf_stg_diag); + } + cb_data->bpf_stg_diag = bpf_stg_diag; + } + + cb->data = cb_data; + return 0; +} + +static int inet_diag_dump_start(struct netlink_callback *cb) +{ + return __inet_diag_dump_start(cb, sizeof(struct inet_diag_req_v2)); +} + +static int inet_diag_dump_start_compat(struct netlink_callback *cb) +{ + return __inet_diag_dump_start(cb, sizeof(struct inet_diag_req)); +} + +static int inet_diag_dump_done(struct netlink_callback *cb) +{ + struct inet_diag_dump_data *cb_data = cb->data; + + bpf_sk_storage_diag_free(cb_data->bpf_stg_diag); + kfree(cb->data); + + return 0; +} + +static int inet_diag_type2proto(int type) +{ + switch (type) { + case TCPDIAG_GETSOCK: + return IPPROTO_TCP; + default: + return 0; + } +} + +static int inet_diag_dump_compat(struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct inet_diag_req *rc = nlmsg_data(cb->nlh); + struct inet_diag_req_v2 req; + + req.sdiag_family = AF_UNSPEC; /* compatibility */ + req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type); + req.idiag_ext = rc->idiag_ext; + req.pad = 0; + req.idiag_states = rc->idiag_states; + req.id = rc->id; + + return __inet_diag_dump(skb, cb, &req); +} + +static int inet_diag_get_exact_compat(struct sk_buff *in_skb, + const struct nlmsghdr *nlh) +{ + struct inet_diag_req *rc = nlmsg_data(nlh); + struct inet_diag_req_v2 req; + + req.sdiag_family = rc->idiag_family; + req.sdiag_protocol = inet_diag_type2proto(nlh->nlmsg_type); + req.idiag_ext = rc->idiag_ext; + req.pad = 0; + req.idiag_states = rc->idiag_states; + req.id = rc->id; + + return inet_diag_cmd_exact(SOCK_DIAG_BY_FAMILY, in_skb, nlh, + sizeof(struct inet_diag_req), &req); +} + +static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh) +{ + int hdrlen = sizeof(struct inet_diag_req); + struct net *net = sock_net(skb->sk); + + if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX || + nlmsg_len(nlh) < hdrlen) + return -EINVAL; + + if (nlh->nlmsg_flags & NLM_F_DUMP) { + struct netlink_dump_control c = { + .start = inet_diag_dump_start_compat, + .done = inet_diag_dump_done, + .dump = inet_diag_dump_compat, + }; + return netlink_dump_start(net->diag_nlsk, skb, nlh, &c); + } + + return inet_diag_get_exact_compat(skb, nlh); +} + +static int inet_diag_handler_cmd(struct sk_buff *skb, struct nlmsghdr *h) +{ + int hdrlen = sizeof(struct inet_diag_req_v2); + struct net *net = sock_net(skb->sk); + + if (nlmsg_len(h) < hdrlen) + return -EINVAL; + + if (h->nlmsg_type == SOCK_DIAG_BY_FAMILY && + h->nlmsg_flags & NLM_F_DUMP) { + struct netlink_dump_control c = { + .start = inet_diag_dump_start, + .done = inet_diag_dump_done, + .dump = inet_diag_dump, + }; + return netlink_dump_start(net->diag_nlsk, skb, h, &c); + } + + return inet_diag_cmd_exact(h->nlmsg_type, skb, h, hdrlen, + nlmsg_data(h)); +} + +static +int inet_diag_handler_get_info(struct sk_buff *skb, struct sock *sk) +{ + const struct inet_diag_handler *handler; + struct nlmsghdr *nlh; + struct nlattr *attr; + struct inet_diag_msg *r; + void *info = NULL; + int err = 0; + + nlh = nlmsg_put(skb, 0, 0, SOCK_DIAG_BY_FAMILY, sizeof(*r), 0); + if (!nlh) + return -ENOMEM; + + r = nlmsg_data(nlh); + memset(r, 0, sizeof(*r)); + inet_diag_msg_common_fill(r, sk); + if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_STREAM) + r->id.idiag_sport = inet_sk(sk)->inet_sport; + r->idiag_state = sk->sk_state; + + if ((err = nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol))) { + nlmsg_cancel(skb, nlh); + return err; + } + + handler = inet_diag_lock_handler(sk->sk_protocol); + if (!handler) { + nlmsg_cancel(skb, nlh); + return -ENOENT; + } + + attr = handler->idiag_info_size + ? nla_reserve_64bit(skb, INET_DIAG_INFO, + handler->idiag_info_size, + INET_DIAG_PAD) + : NULL; + if (attr) + info = nla_data(attr); + + handler->idiag_get_info(sk, r, info); + inet_diag_unlock_handler(handler); + + nlmsg_end(skb, nlh); + return 0; +} + +static const struct sock_diag_handler inet_diag_handler = { + .owner = THIS_MODULE, + .family = AF_INET, + .dump = inet_diag_handler_cmd, + .get_info = inet_diag_handler_get_info, + .destroy = inet_diag_handler_cmd, +}; + +static const struct sock_diag_handler inet6_diag_handler = { + .owner = THIS_MODULE, + .family = AF_INET6, + .dump = inet_diag_handler_cmd, + .get_info = inet_diag_handler_get_info, + .destroy = inet_diag_handler_cmd, +}; + +int inet_diag_register(const struct inet_diag_handler *h) +{ + const __u16 type = h->idiag_type; + + if (type >= IPPROTO_MAX) + return -EINVAL; + + return !cmpxchg((const struct inet_diag_handler **)&inet_diag_table[type], + NULL, h) ? 0 : -EEXIST; +} +EXPORT_SYMBOL_GPL(inet_diag_register); + +void inet_diag_unregister(const struct inet_diag_handler *h) +{ + const __u16 type = h->idiag_type; + + if (type >= IPPROTO_MAX) + return; + + xchg((const struct inet_diag_handler **)&inet_diag_table[type], + NULL); +} +EXPORT_SYMBOL_GPL(inet_diag_unregister); + +static const struct sock_diag_inet_compat inet_diag_compat = { + .owner = THIS_MODULE, + .fn = inet_diag_rcv_msg_compat, +}; + +static int __init inet_diag_init(void) +{ + const int inet_diag_table_size = (IPPROTO_MAX * + sizeof(struct inet_diag_handler *)); + int err = -ENOMEM; + + inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL); + if (!inet_diag_table) + goto out; + + err = sock_diag_register(&inet_diag_handler); + if (err) + goto out_free_nl; + + err = sock_diag_register(&inet6_diag_handler); + if (err) + goto out_free_inet; + + sock_diag_register_inet_compat(&inet_diag_compat); +out: + return err; + +out_free_inet: + sock_diag_unregister(&inet_diag_handler); +out_free_nl: + kfree(inet_diag_table); + goto out; +} + +static void __exit inet_diag_exit(void) +{ + sock_diag_unregister(&inet6_diag_handler); + sock_diag_unregister(&inet_diag_handler); + sock_diag_unregister_inet_compat(&inet_diag_compat); + kfree(inet_diag_table); +} + +module_init(inet_diag_init); +module_exit(inet_diag_exit); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("INET/INET6: socket monitoring via SOCK_DIAG"); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2 /* AF_INET */); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10 /* AF_INET6 */); |