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-rw-r--r--net/ipv4/ping.c1209
1 files changed, 1209 insertions, 0 deletions
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
new file mode 100644
index 000000000..2e7abad48
--- /dev/null
+++ b/net/ipv4/ping.c
@@ -0,0 +1,1209 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * "Ping" sockets
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Based on ipv4/udp.c code.
+ *
+ * Authors: Vasiliy Kulikov / Openwall (for Linux 2.6),
+ * Pavel Kankovsky (for Linux 2.4.32)
+ *
+ * Pavel gave all rights to bugs to Vasiliy,
+ * none of the bugs are Pavel's now.
+ *
+ */
+
+#include <linux/uaccess.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <net/snmp.h>
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/protocol.h>
+#include <linux/skbuff.h>
+#include <linux/proc_fs.h>
+#include <linux/export.h>
+#include <net/sock.h>
+#include <net/ping.h>
+#include <net/udp.h>
+#include <net/route.h>
+#include <net/inet_common.h>
+#include <net/checksum.h>
+
+#if IS_ENABLED(CONFIG_IPV6)
+#include <linux/in6.h>
+#include <linux/icmpv6.h>
+#include <net/addrconf.h>
+#include <net/ipv6.h>
+#include <net/transp_v6.h>
+#endif
+
+struct ping_table {
+ struct hlist_nulls_head hash[PING_HTABLE_SIZE];
+ rwlock_t lock;
+};
+
+static struct ping_table ping_table;
+struct pingv6_ops pingv6_ops;
+EXPORT_SYMBOL_GPL(pingv6_ops);
+
+static u16 ping_port_rover;
+
+static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
+{
+ u32 res = (num + net_hash_mix(net)) & mask;
+
+ pr_debug("hash(%u) = %u\n", num, res);
+ return res;
+}
+EXPORT_SYMBOL_GPL(ping_hash);
+
+static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
+ struct net *net, unsigned int num)
+{
+ return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
+}
+
+int ping_get_port(struct sock *sk, unsigned short ident)
+{
+ struct hlist_nulls_node *node;
+ struct hlist_nulls_head *hlist;
+ struct inet_sock *isk, *isk2;
+ struct sock *sk2 = NULL;
+
+ isk = inet_sk(sk);
+ write_lock_bh(&ping_table.lock);
+ if (ident == 0) {
+ u32 i;
+ u16 result = ping_port_rover + 1;
+
+ for (i = 0; i < (1L << 16); i++, result++) {
+ if (!result)
+ result++; /* avoid zero */
+ hlist = ping_hashslot(&ping_table, sock_net(sk),
+ result);
+ ping_portaddr_for_each_entry(sk2, node, hlist) {
+ isk2 = inet_sk(sk2);
+
+ if (isk2->inet_num == result)
+ goto next_port;
+ }
+
+ /* found */
+ ping_port_rover = ident = result;
+ break;
+next_port:
+ ;
+ }
+ if (i >= (1L << 16))
+ goto fail;
+ } else {
+ hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
+ ping_portaddr_for_each_entry(sk2, node, hlist) {
+ isk2 = inet_sk(sk2);
+
+ /* BUG? Why is this reuse and not reuseaddr? ping.c
+ * doesn't turn off SO_REUSEADDR, and it doesn't expect
+ * that other ping processes can steal its packets.
+ */
+ if ((isk2->inet_num == ident) &&
+ (sk2 != sk) &&
+ (!sk2->sk_reuse || !sk->sk_reuse))
+ goto fail;
+ }
+ }
+
+ pr_debug("found port/ident = %d\n", ident);
+ isk->inet_num = ident;
+ if (sk_unhashed(sk)) {
+ pr_debug("was not hashed\n");
+ sock_hold(sk);
+ hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
+ sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
+ }
+ write_unlock_bh(&ping_table.lock);
+ return 0;
+
+fail:
+ write_unlock_bh(&ping_table.lock);
+ return 1;
+}
+EXPORT_SYMBOL_GPL(ping_get_port);
+
+int ping_hash(struct sock *sk)
+{
+ pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
+ BUG(); /* "Please do not press this button again." */
+
+ return 0;
+}
+
+void ping_unhash(struct sock *sk)
+{
+ struct inet_sock *isk = inet_sk(sk);
+
+ pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
+ write_lock_bh(&ping_table.lock);
+ if (sk_hashed(sk)) {
+ hlist_nulls_del(&sk->sk_nulls_node);
+ sk_nulls_node_init(&sk->sk_nulls_node);
+ sock_put(sk);
+ isk->inet_num = 0;
+ isk->inet_sport = 0;
+ sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
+ }
+ write_unlock_bh(&ping_table.lock);
+}
+EXPORT_SYMBOL_GPL(ping_unhash);
+
+static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
+{
+ struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
+ struct sock *sk = NULL;
+ struct inet_sock *isk;
+ struct hlist_nulls_node *hnode;
+ int dif, sdif;
+
+ if (skb->protocol == htons(ETH_P_IP)) {
+ dif = inet_iif(skb);
+ sdif = inet_sdif(skb);
+ pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
+ (int)ident, &ip_hdr(skb)->daddr, dif);
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (skb->protocol == htons(ETH_P_IPV6)) {
+ dif = inet6_iif(skb);
+ sdif = inet6_sdif(skb);
+ pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
+ (int)ident, &ipv6_hdr(skb)->daddr, dif);
+#endif
+ } else {
+ return NULL;
+ }
+
+ read_lock_bh(&ping_table.lock);
+
+ ping_portaddr_for_each_entry(sk, hnode, hslot) {
+ isk = inet_sk(sk);
+
+ pr_debug("iterate\n");
+ if (isk->inet_num != ident)
+ continue;
+
+ if (skb->protocol == htons(ETH_P_IP) &&
+ sk->sk_family == AF_INET) {
+ pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
+ (int) isk->inet_num, &isk->inet_rcv_saddr,
+ sk->sk_bound_dev_if);
+
+ if (isk->inet_rcv_saddr &&
+ isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
+ continue;
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (skb->protocol == htons(ETH_P_IPV6) &&
+ sk->sk_family == AF_INET6) {
+
+ pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
+ (int) isk->inet_num,
+ &sk->sk_v6_rcv_saddr,
+ sk->sk_bound_dev_if);
+
+ if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
+ !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
+ &ipv6_hdr(skb)->daddr))
+ continue;
+#endif
+ } else {
+ continue;
+ }
+
+ if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif &&
+ sk->sk_bound_dev_if != sdif)
+ continue;
+
+ sock_hold(sk);
+ goto exit;
+ }
+
+ sk = NULL;
+exit:
+ read_unlock_bh(&ping_table.lock);
+
+ return sk;
+}
+
+static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
+ kgid_t *high)
+{
+ kgid_t *data = net->ipv4.ping_group_range.range;
+ unsigned int seq;
+
+ do {
+ seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
+
+ *low = data[0];
+ *high = data[1];
+ } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
+}
+
+
+int ping_init_sock(struct sock *sk)
+{
+ struct net *net = sock_net(sk);
+ kgid_t group = current_egid();
+ struct group_info *group_info;
+ int i;
+ kgid_t low, high;
+ int ret = 0;
+
+ if (sk->sk_family == AF_INET6)
+ sk->sk_ipv6only = 1;
+
+ inet_get_ping_group_range_net(net, &low, &high);
+ if (gid_lte(low, group) && gid_lte(group, high))
+ return 0;
+
+ group_info = get_current_groups();
+ for (i = 0; i < group_info->ngroups; i++) {
+ kgid_t gid = group_info->gid[i];
+
+ if (gid_lte(low, gid) && gid_lte(gid, high))
+ goto out_release_group;
+ }
+
+ ret = -EACCES;
+
+out_release_group:
+ put_group_info(group_info);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ping_init_sock);
+
+void ping_close(struct sock *sk, long timeout)
+{
+ pr_debug("ping_close(sk=%p,sk->num=%u)\n",
+ inet_sk(sk), inet_sk(sk)->inet_num);
+ pr_debug("isk->refcnt = %d\n", refcount_read(&sk->sk_refcnt));
+
+ sk_common_release(sk);
+}
+EXPORT_SYMBOL_GPL(ping_close);
+
+/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
+static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
+ struct sockaddr *uaddr, int addr_len) {
+ struct net *net = sock_net(sk);
+ if (sk->sk_family == AF_INET) {
+ struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
+ u32 tb_id = RT_TABLE_LOCAL;
+ int chk_addr_ret;
+
+ if (addr_len < sizeof(*addr))
+ return -EINVAL;
+
+ if (addr->sin_family != AF_INET &&
+ !(addr->sin_family == AF_UNSPEC &&
+ addr->sin_addr.s_addr == htonl(INADDR_ANY)))
+ return -EAFNOSUPPORT;
+
+ pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
+ sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
+
+ tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
+ chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
+
+ if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
+ chk_addr_ret = RTN_LOCAL;
+
+ if ((!inet_can_nonlocal_bind(net, isk) &&
+ chk_addr_ret != RTN_LOCAL) ||
+ chk_addr_ret == RTN_MULTICAST ||
+ chk_addr_ret == RTN_BROADCAST)
+ return -EADDRNOTAVAIL;
+
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (sk->sk_family == AF_INET6) {
+ struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
+ int addr_type, scoped, has_addr;
+ struct net_device *dev = NULL;
+
+ if (addr_len < sizeof(*addr))
+ return -EINVAL;
+
+ if (addr->sin6_family != AF_INET6)
+ return -EAFNOSUPPORT;
+
+ pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
+ sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
+
+ addr_type = ipv6_addr_type(&addr->sin6_addr);
+ scoped = __ipv6_addr_needs_scope_id(addr_type);
+ if ((addr_type != IPV6_ADDR_ANY &&
+ !(addr_type & IPV6_ADDR_UNICAST)) ||
+ (scoped && !addr->sin6_scope_id))
+ return -EINVAL;
+
+ rcu_read_lock();
+ if (addr->sin6_scope_id) {
+ dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
+ if (!dev) {
+ rcu_read_unlock();
+ return -ENODEV;
+ }
+ }
+
+ if (!dev && sk->sk_bound_dev_if) {
+ dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
+ if (!dev) {
+ rcu_read_unlock();
+ return -ENODEV;
+ }
+ }
+ has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
+ scoped);
+ rcu_read_unlock();
+
+ if (!(ipv6_can_nonlocal_bind(net, isk) || has_addr ||
+ addr_type == IPV6_ADDR_ANY))
+ return -EADDRNOTAVAIL;
+
+ if (scoped)
+ sk->sk_bound_dev_if = addr->sin6_scope_id;
+#endif
+ } else {
+ return -EAFNOSUPPORT;
+ }
+ return 0;
+}
+
+static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
+{
+ if (saddr->sa_family == AF_INET) {
+ struct inet_sock *isk = inet_sk(sk);
+ struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
+ isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (saddr->sa_family == AF_INET6) {
+ struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
+#endif
+ }
+}
+
+static void ping_clear_saddr(struct sock *sk, int dif)
+{
+ sk->sk_bound_dev_if = dif;
+ if (sk->sk_family == AF_INET) {
+ struct inet_sock *isk = inet_sk(sk);
+ isk->inet_rcv_saddr = isk->inet_saddr = 0;
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (sk->sk_family == AF_INET6) {
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
+ memset(&np->saddr, 0, sizeof(np->saddr));
+#endif
+ }
+}
+/*
+ * We need our own bind because there are no privileged id's == local ports.
+ * Moreover, we don't allow binding to multi- and broadcast addresses.
+ */
+
+int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
+{
+ struct inet_sock *isk = inet_sk(sk);
+ unsigned short snum;
+ int err;
+ int dif = sk->sk_bound_dev_if;
+
+ err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
+ if (err)
+ return err;
+
+ lock_sock(sk);
+
+ err = -EINVAL;
+ if (isk->inet_num != 0)
+ goto out;
+
+ err = -EADDRINUSE;
+ ping_set_saddr(sk, uaddr);
+ snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
+ if (ping_get_port(sk, snum) != 0) {
+ ping_clear_saddr(sk, dif);
+ goto out;
+ }
+
+ pr_debug("after bind(): num = %hu, dif = %d\n",
+ isk->inet_num,
+ sk->sk_bound_dev_if);
+
+ err = 0;
+ if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
+ sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
+#if IS_ENABLED(CONFIG_IPV6)
+ if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
+ sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
+#endif
+
+ if (snum)
+ sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
+ isk->inet_sport = htons(isk->inet_num);
+ isk->inet_daddr = 0;
+ isk->inet_dport = 0;
+
+#if IS_ENABLED(CONFIG_IPV6)
+ if (sk->sk_family == AF_INET6)
+ memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
+#endif
+
+ sk_dst_reset(sk);
+out:
+ release_sock(sk);
+ pr_debug("ping_v4_bind -> %d\n", err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(ping_bind);
+
+/*
+ * Is this a supported type of ICMP message?
+ */
+
+static inline int ping_supported(int family, int type, int code)
+{
+ return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
+ (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
+}
+
+/*
+ * This routine is called by the ICMP module when it gets some
+ * sort of error condition.
+ */
+
+void ping_err(struct sk_buff *skb, int offset, u32 info)
+{
+ int family;
+ struct icmphdr *icmph;
+ struct inet_sock *inet_sock;
+ int type;
+ int code;
+ struct net *net = dev_net(skb->dev);
+ struct sock *sk;
+ int harderr;
+ int err;
+
+ if (skb->protocol == htons(ETH_P_IP)) {
+ family = AF_INET;
+ type = icmp_hdr(skb)->type;
+ code = icmp_hdr(skb)->code;
+ icmph = (struct icmphdr *)(skb->data + offset);
+ } else if (skb->protocol == htons(ETH_P_IPV6)) {
+ family = AF_INET6;
+ type = icmp6_hdr(skb)->icmp6_type;
+ code = icmp6_hdr(skb)->icmp6_code;
+ icmph = (struct icmphdr *) (skb->data + offset);
+ } else {
+ BUG();
+ }
+
+ /* We assume the packet has already been checked by icmp_unreach */
+
+ if (!ping_supported(family, icmph->type, icmph->code))
+ return;
+
+ pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
+ skb->protocol, type, code, ntohs(icmph->un.echo.id),
+ ntohs(icmph->un.echo.sequence));
+
+ sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
+ if (!sk) {
+ pr_debug("no socket, dropping\n");
+ return; /* No socket for error */
+ }
+ pr_debug("err on socket %p\n", sk);
+
+ err = 0;
+ harderr = 0;
+ inet_sock = inet_sk(sk);
+
+ if (skb->protocol == htons(ETH_P_IP)) {
+ switch (type) {
+ default:
+ case ICMP_TIME_EXCEEDED:
+ err = EHOSTUNREACH;
+ break;
+ case ICMP_SOURCE_QUENCH:
+ /* This is not a real error but ping wants to see it.
+ * Report it with some fake errno.
+ */
+ err = EREMOTEIO;
+ break;
+ case ICMP_PARAMETERPROB:
+ err = EPROTO;
+ harderr = 1;
+ break;
+ case ICMP_DEST_UNREACH:
+ if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
+ ipv4_sk_update_pmtu(skb, sk, info);
+ if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
+ err = EMSGSIZE;
+ harderr = 1;
+ break;
+ }
+ goto out;
+ }
+ err = EHOSTUNREACH;
+ if (code <= NR_ICMP_UNREACH) {
+ harderr = icmp_err_convert[code].fatal;
+ err = icmp_err_convert[code].errno;
+ }
+ break;
+ case ICMP_REDIRECT:
+ /* See ICMP_SOURCE_QUENCH */
+ ipv4_sk_redirect(skb, sk);
+ err = EREMOTEIO;
+ break;
+ }
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (skb->protocol == htons(ETH_P_IPV6)) {
+ harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
+#endif
+ }
+
+ /*
+ * RFC1122: OK. Passes ICMP errors back to application, as per
+ * 4.1.3.3.
+ */
+ if ((family == AF_INET && !inet_sock->recverr) ||
+ (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
+ if (!harderr || sk->sk_state != TCP_ESTABLISHED)
+ goto out;
+ } else {
+ if (family == AF_INET) {
+ ip_icmp_error(sk, skb, err, 0 /* no remote port */,
+ info, (u8 *)icmph);
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (family == AF_INET6) {
+ pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
+ info, (u8 *)icmph);
+#endif
+ }
+ }
+ sk->sk_err = err;
+ sk->sk_error_report(sk);
+out:
+ sock_put(sk);
+}
+EXPORT_SYMBOL_GPL(ping_err);
+
+/*
+ * Copy and checksum an ICMP Echo packet from user space into a buffer
+ * starting from the payload.
+ */
+
+int ping_getfrag(void *from, char *to,
+ int offset, int fraglen, int odd, struct sk_buff *skb)
+{
+ struct pingfakehdr *pfh = (struct pingfakehdr *)from;
+
+ if (offset == 0) {
+ fraglen -= sizeof(struct icmphdr);
+ if (fraglen < 0)
+ BUG();
+ if (!csum_and_copy_from_iter_full(to + sizeof(struct icmphdr),
+ fraglen, &pfh->wcheck,
+ &pfh->msg->msg_iter))
+ return -EFAULT;
+ } else if (offset < sizeof(struct icmphdr)) {
+ BUG();
+ } else {
+ if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
+ &pfh->msg->msg_iter))
+ return -EFAULT;
+ }
+
+#if IS_ENABLED(CONFIG_IPV6)
+ /* For IPv6, checksum each skb as we go along, as expected by
+ * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
+ * wcheck, it will be finalized in ping_v4_push_pending_frames.
+ */
+ if (pfh->family == AF_INET6) {
+ skb->csum = pfh->wcheck;
+ skb->ip_summed = CHECKSUM_NONE;
+ pfh->wcheck = 0;
+ }
+#endif
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ping_getfrag);
+
+static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
+ struct flowi4 *fl4)
+{
+ struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
+
+ if (!skb)
+ return 0;
+ pfh->wcheck = csum_partial((char *)&pfh->icmph,
+ sizeof(struct icmphdr), pfh->wcheck);
+ pfh->icmph.checksum = csum_fold(pfh->wcheck);
+ memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
+ skb->ip_summed = CHECKSUM_NONE;
+ return ip_push_pending_frames(sk, fl4);
+}
+
+int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
+ void *user_icmph, size_t icmph_len) {
+ u8 type, code;
+
+ if (len > 0xFFFF)
+ return -EMSGSIZE;
+
+ /* Must have at least a full ICMP header. */
+ if (len < icmph_len)
+ return -EINVAL;
+
+ /*
+ * Check the flags.
+ */
+
+ /* Mirror BSD error message compatibility */
+ if (msg->msg_flags & MSG_OOB)
+ return -EOPNOTSUPP;
+
+ /*
+ * Fetch the ICMP header provided by the userland.
+ * iovec is modified! The ICMP header is consumed.
+ */
+ if (memcpy_from_msg(user_icmph, msg, icmph_len))
+ return -EFAULT;
+
+ if (family == AF_INET) {
+ type = ((struct icmphdr *) user_icmph)->type;
+ code = ((struct icmphdr *) user_icmph)->code;
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (family == AF_INET6) {
+ type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
+ code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
+#endif
+ } else {
+ BUG();
+ }
+
+ if (!ping_supported(family, type, code))
+ return -EINVAL;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ping_common_sendmsg);
+
+static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
+{
+ struct net *net = sock_net(sk);
+ struct flowi4 fl4;
+ struct inet_sock *inet = inet_sk(sk);
+ struct ipcm_cookie ipc;
+ struct icmphdr user_icmph;
+ struct pingfakehdr pfh;
+ struct rtable *rt = NULL;
+ struct ip_options_data opt_copy;
+ int free = 0;
+ __be32 saddr, daddr, faddr;
+ u8 tos;
+ int err;
+
+ pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
+
+ err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
+ sizeof(user_icmph));
+ if (err)
+ return err;
+
+ /*
+ * Get and verify the address.
+ */
+
+ if (msg->msg_name) {
+ DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
+ if (msg->msg_namelen < sizeof(*usin))
+ return -EINVAL;
+ if (usin->sin_family != AF_INET)
+ return -EAFNOSUPPORT;
+ daddr = usin->sin_addr.s_addr;
+ /* no remote port */
+ } else {
+ if (sk->sk_state != TCP_ESTABLISHED)
+ return -EDESTADDRREQ;
+ daddr = inet->inet_daddr;
+ /* no remote port */
+ }
+
+ ipcm_init_sk(&ipc, inet);
+
+ if (msg->msg_controllen) {
+ err = ip_cmsg_send(sk, msg, &ipc, false);
+ if (unlikely(err)) {
+ kfree(ipc.opt);
+ return err;
+ }
+ if (ipc.opt)
+ free = 1;
+ }
+ if (!ipc.opt) {
+ struct ip_options_rcu *inet_opt;
+
+ rcu_read_lock();
+ inet_opt = rcu_dereference(inet->inet_opt);
+ if (inet_opt) {
+ memcpy(&opt_copy, inet_opt,
+ sizeof(*inet_opt) + inet_opt->opt.optlen);
+ ipc.opt = &opt_copy.opt;
+ }
+ rcu_read_unlock();
+ }
+
+ saddr = ipc.addr;
+ ipc.addr = faddr = daddr;
+
+ if (ipc.opt && ipc.opt->opt.srr) {
+ if (!daddr) {
+ err = -EINVAL;
+ goto out_free;
+ }
+ faddr = ipc.opt->opt.faddr;
+ }
+ tos = get_rttos(&ipc, inet);
+ if (sock_flag(sk, SOCK_LOCALROUTE) ||
+ (msg->msg_flags & MSG_DONTROUTE) ||
+ (ipc.opt && ipc.opt->opt.is_strictroute)) {
+ tos |= RTO_ONLINK;
+ }
+
+ if (ipv4_is_multicast(daddr)) {
+ if (!ipc.oif)
+ ipc.oif = inet->mc_index;
+ if (!saddr)
+ saddr = inet->mc_addr;
+ } else if (!ipc.oif)
+ ipc.oif = inet->uc_index;
+
+ flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
+ RT_SCOPE_UNIVERSE, sk->sk_protocol,
+ inet_sk_flowi_flags(sk), faddr, saddr, 0, 0,
+ sk->sk_uid);
+
+ fl4.fl4_icmp_type = user_icmph.type;
+ fl4.fl4_icmp_code = user_icmph.code;
+
+ security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
+ rt = ip_route_output_flow(net, &fl4, sk);
+ if (IS_ERR(rt)) {
+ err = PTR_ERR(rt);
+ rt = NULL;
+ if (err == -ENETUNREACH)
+ IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
+ goto out;
+ }
+
+ err = -EACCES;
+ if ((rt->rt_flags & RTCF_BROADCAST) &&
+ !sock_flag(sk, SOCK_BROADCAST))
+ goto out;
+
+ if (msg->msg_flags & MSG_CONFIRM)
+ goto do_confirm;
+back_from_confirm:
+
+ if (!ipc.addr)
+ ipc.addr = fl4.daddr;
+
+ lock_sock(sk);
+
+ pfh.icmph.type = user_icmph.type; /* already checked */
+ pfh.icmph.code = user_icmph.code; /* ditto */
+ pfh.icmph.checksum = 0;
+ pfh.icmph.un.echo.id = inet->inet_sport;
+ pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
+ pfh.msg = msg;
+ pfh.wcheck = 0;
+ pfh.family = AF_INET;
+
+ err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
+ 0, &ipc, &rt, msg->msg_flags);
+ if (err)
+ ip_flush_pending_frames(sk);
+ else
+ err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
+ release_sock(sk);
+
+out:
+ ip_rt_put(rt);
+out_free:
+ if (free)
+ kfree(ipc.opt);
+ if (!err) {
+ icmp_out_count(sock_net(sk), user_icmph.type);
+ return len;
+ }
+ return err;
+
+do_confirm:
+ if (msg->msg_flags & MSG_PROBE)
+ dst_confirm_neigh(&rt->dst, &fl4.daddr);
+ if (!(msg->msg_flags & MSG_PROBE) || len)
+ goto back_from_confirm;
+ err = 0;
+ goto out;
+}
+
+int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
+ int flags, int *addr_len)
+{
+ struct inet_sock *isk = inet_sk(sk);
+ int family = sk->sk_family;
+ struct sk_buff *skb;
+ int copied, err;
+
+ pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
+
+ err = -EOPNOTSUPP;
+ if (flags & MSG_OOB)
+ goto out;
+
+ if (flags & MSG_ERRQUEUE)
+ return inet_recv_error(sk, msg, len, addr_len);
+
+ skb = skb_recv_datagram(sk, flags, noblock, &err);
+ if (!skb)
+ goto out;
+
+ copied = skb->len;
+ if (copied > len) {
+ msg->msg_flags |= MSG_TRUNC;
+ copied = len;
+ }
+
+ /* Don't bother checking the checksum */
+ err = skb_copy_datagram_msg(skb, 0, msg, copied);
+ if (err)
+ goto done;
+
+ sock_recv_timestamp(msg, sk, skb);
+
+ /* Copy the address and add cmsg data. */
+ if (family == AF_INET) {
+ DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
+
+ if (sin) {
+ sin->sin_family = AF_INET;
+ sin->sin_port = 0 /* skb->h.uh->source */;
+ sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
+ memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
+ *addr_len = sizeof(*sin);
+ }
+
+ if (isk->cmsg_flags)
+ ip_cmsg_recv(msg, skb);
+
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (family == AF_INET6) {
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct ipv6hdr *ip6 = ipv6_hdr(skb);
+ DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
+
+ if (sin6) {
+ sin6->sin6_family = AF_INET6;
+ sin6->sin6_port = 0;
+ sin6->sin6_addr = ip6->saddr;
+ sin6->sin6_flowinfo = 0;
+ if (np->sndflow)
+ sin6->sin6_flowinfo = ip6_flowinfo(ip6);
+ sin6->sin6_scope_id =
+ ipv6_iface_scope_id(&sin6->sin6_addr,
+ inet6_iif(skb));
+ *addr_len = sizeof(*sin6);
+ }
+
+ if (inet6_sk(sk)->rxopt.all)
+ pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
+ if (skb->protocol == htons(ETH_P_IPV6) &&
+ inet6_sk(sk)->rxopt.all)
+ pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
+ else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
+ ip_cmsg_recv(msg, skb);
+#endif
+ } else {
+ BUG();
+ }
+
+ err = copied;
+
+done:
+ skb_free_datagram(sk, skb);
+out:
+ pr_debug("ping_recvmsg -> %d\n", err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(ping_recvmsg);
+
+int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+ pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
+ inet_sk(sk), inet_sk(sk)->inet_num, skb);
+ if (sock_queue_rcv_skb(sk, skb) < 0) {
+ kfree_skb(skb);
+ pr_debug("ping_queue_rcv_skb -> failed\n");
+ return -1;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
+
+
+/*
+ * All we need to do is get the socket.
+ */
+
+bool ping_rcv(struct sk_buff *skb)
+{
+ struct sock *sk;
+ struct net *net = dev_net(skb->dev);
+ struct icmphdr *icmph = icmp_hdr(skb);
+ bool rc = false;
+
+ /* We assume the packet has already been checked by icmp_rcv */
+
+ pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
+ skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
+
+ /* Push ICMP header back */
+ skb_push(skb, skb->data - (u8 *)icmph);
+
+ sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
+ if (sk) {
+ struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
+
+ pr_debug("rcv on socket %p\n", sk);
+ if (skb2 && !ping_queue_rcv_skb(sk, skb2))
+ rc = true;
+ sock_put(sk);
+ }
+
+ if (!rc)
+ pr_debug("no socket, dropping\n");
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(ping_rcv);
+
+struct proto ping_prot = {
+ .name = "PING",
+ .owner = THIS_MODULE,
+ .init = ping_init_sock,
+ .close = ping_close,
+ .connect = ip4_datagram_connect,
+ .disconnect = __udp_disconnect,
+ .setsockopt = ip_setsockopt,
+ .getsockopt = ip_getsockopt,
+ .sendmsg = ping_v4_sendmsg,
+ .recvmsg = ping_recvmsg,
+ .bind = ping_bind,
+ .backlog_rcv = ping_queue_rcv_skb,
+ .release_cb = ip4_datagram_release_cb,
+ .hash = ping_hash,
+ .unhash = ping_unhash,
+ .get_port = ping_get_port,
+ .obj_size = sizeof(struct inet_sock),
+};
+EXPORT_SYMBOL(ping_prot);
+
+#ifdef CONFIG_PROC_FS
+
+static struct sock *ping_get_first(struct seq_file *seq, int start)
+{
+ struct sock *sk;
+ struct ping_iter_state *state = seq->private;
+ struct net *net = seq_file_net(seq);
+
+ for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
+ ++state->bucket) {
+ struct hlist_nulls_node *node;
+ struct hlist_nulls_head *hslot;
+
+ hslot = &ping_table.hash[state->bucket];
+
+ if (hlist_nulls_empty(hslot))
+ continue;
+
+ sk_nulls_for_each(sk, node, hslot) {
+ if (net_eq(sock_net(sk), net) &&
+ sk->sk_family == state->family)
+ goto found;
+ }
+ }
+ sk = NULL;
+found:
+ return sk;
+}
+
+static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
+{
+ struct ping_iter_state *state = seq->private;
+ struct net *net = seq_file_net(seq);
+
+ do {
+ sk = sk_nulls_next(sk);
+ } while (sk && (!net_eq(sock_net(sk), net)));
+
+ if (!sk)
+ return ping_get_first(seq, state->bucket + 1);
+ return sk;
+}
+
+static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
+{
+ struct sock *sk = ping_get_first(seq, 0);
+
+ if (sk)
+ while (pos && (sk = ping_get_next(seq, sk)) != NULL)
+ --pos;
+ return pos ? NULL : sk;
+}
+
+void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
+ __acquires(ping_table.lock)
+{
+ struct ping_iter_state *state = seq->private;
+ state->bucket = 0;
+ state->family = family;
+
+ read_lock_bh(&ping_table.lock);
+
+ return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
+}
+EXPORT_SYMBOL_GPL(ping_seq_start);
+
+static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ return ping_seq_start(seq, pos, AF_INET);
+}
+
+void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct sock *sk;
+
+ if (v == SEQ_START_TOKEN)
+ sk = ping_get_idx(seq, 0);
+ else
+ sk = ping_get_next(seq, v);
+
+ ++*pos;
+ return sk;
+}
+EXPORT_SYMBOL_GPL(ping_seq_next);
+
+void ping_seq_stop(struct seq_file *seq, void *v)
+ __releases(ping_table.lock)
+{
+ read_unlock_bh(&ping_table.lock);
+}
+EXPORT_SYMBOL_GPL(ping_seq_stop);
+
+static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
+ int bucket)
+{
+ struct inet_sock *inet = inet_sk(sp);
+ __be32 dest = inet->inet_daddr;
+ __be32 src = inet->inet_rcv_saddr;
+ __u16 destp = ntohs(inet->inet_dport);
+ __u16 srcp = ntohs(inet->inet_sport);
+
+ seq_printf(f, "%5d: %08X:%04X %08X:%04X"
+ " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
+ bucket, src, srcp, dest, destp, sp->sk_state,
+ sk_wmem_alloc_get(sp),
+ sk_rmem_alloc_get(sp),
+ 0, 0L, 0,
+ from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
+ 0, sock_i_ino(sp),
+ refcount_read(&sp->sk_refcnt), sp,
+ atomic_read(&sp->sk_drops));
+}
+
+static int ping_v4_seq_show(struct seq_file *seq, void *v)
+{
+ seq_setwidth(seq, 127);
+ if (v == SEQ_START_TOKEN)
+ seq_puts(seq, " sl local_address rem_address st tx_queue "
+ "rx_queue tr tm->when retrnsmt uid timeout "
+ "inode ref pointer drops");
+ else {
+ struct ping_iter_state *state = seq->private;
+
+ ping_v4_format_sock(v, seq, state->bucket);
+ }
+ seq_pad(seq, '\n');
+ return 0;
+}
+
+static const struct seq_operations ping_v4_seq_ops = {
+ .start = ping_v4_seq_start,
+ .show = ping_v4_seq_show,
+ .next = ping_seq_next,
+ .stop = ping_seq_stop,
+};
+
+static int __net_init ping_v4_proc_init_net(struct net *net)
+{
+ if (!proc_create_net("icmp", 0444, net->proc_net, &ping_v4_seq_ops,
+ sizeof(struct ping_iter_state)))
+ return -ENOMEM;
+ return 0;
+}
+
+static void __net_exit ping_v4_proc_exit_net(struct net *net)
+{
+ remove_proc_entry("icmp", net->proc_net);
+}
+
+static struct pernet_operations ping_v4_net_ops = {
+ .init = ping_v4_proc_init_net,
+ .exit = ping_v4_proc_exit_net,
+};
+
+int __init ping_proc_init(void)
+{
+ return register_pernet_subsys(&ping_v4_net_ops);
+}
+
+void ping_proc_exit(void)
+{
+ unregister_pernet_subsys(&ping_v4_net_ops);
+}
+
+#endif
+
+void __init ping_init(void)
+{
+ int i;
+
+ for (i = 0; i < PING_HTABLE_SIZE; i++)
+ INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
+ rwlock_init(&ping_table.lock);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 18:38:50 +0000