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v3.15
 
   1/*
   2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   3 *		operating system.  INET is implemented using the  BSD Socket
   4 *		interface as the means of communication with the user level.
   5 *
   6 *		"Ping" sockets
   7 *
   8 *		This program is free software; you can redistribute it and/or
   9 *		modify it under the terms of the GNU General Public License
  10 *		as published by the Free Software Foundation; either version
  11 *		2 of the License, or (at your option) any later version.
  12 *
  13 * Based on ipv4/udp.c code.
  14 *
  15 * Authors:	Vasiliy Kulikov / Openwall (for Linux 2.6),
  16 *		Pavel Kankovsky (for Linux 2.4.32)
  17 *
  18 * Pavel gave all rights to bugs to Vasiliy,
  19 * none of the bugs are Pavel's now.
  20 *
  21 */
  22
  23#include <linux/uaccess.h>
  24#include <linux/types.h>
  25#include <linux/fcntl.h>
  26#include <linux/socket.h>
  27#include <linux/sockios.h>
  28#include <linux/in.h>
  29#include <linux/errno.h>
  30#include <linux/timer.h>
  31#include <linux/mm.h>
  32#include <linux/inet.h>
  33#include <linux/netdevice.h>
  34#include <net/snmp.h>
  35#include <net/ip.h>
  36#include <net/icmp.h>
  37#include <net/protocol.h>
  38#include <linux/skbuff.h>
  39#include <linux/proc_fs.h>
  40#include <linux/export.h>
  41#include <net/sock.h>
  42#include <net/ping.h>
  43#include <net/udp.h>
  44#include <net/route.h>
  45#include <net/inet_common.h>
  46#include <net/checksum.h>
  47
  48#if IS_ENABLED(CONFIG_IPV6)
  49#include <linux/in6.h>
  50#include <linux/icmpv6.h>
  51#include <net/addrconf.h>
  52#include <net/ipv6.h>
  53#include <net/transp_v6.h>
  54#endif
  55
  56struct ping_table {
  57	struct hlist_nulls_head	hash[PING_HTABLE_SIZE];
  58	rwlock_t		lock;
  59};
  60
  61static struct ping_table ping_table;
  62struct pingv6_ops pingv6_ops;
  63EXPORT_SYMBOL_GPL(pingv6_ops);
  64
  65static u16 ping_port_rover;
  66
  67static inline int ping_hashfn(struct net *net, unsigned int num, unsigned int mask)
  68{
  69	int res = (num + net_hash_mix(net)) & mask;
  70
  71	pr_debug("hash(%d) = %d\n", num, res);
  72	return res;
  73}
  74EXPORT_SYMBOL_GPL(ping_hash);
  75
  76static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
  77					     struct net *net, unsigned int num)
  78{
  79	return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
  80}
  81
  82int ping_get_port(struct sock *sk, unsigned short ident)
  83{
  84	struct hlist_nulls_node *node;
  85	struct hlist_nulls_head *hlist;
  86	struct inet_sock *isk, *isk2;
  87	struct sock *sk2 = NULL;
  88
  89	isk = inet_sk(sk);
  90	write_lock_bh(&ping_table.lock);
  91	if (ident == 0) {
  92		u32 i;
  93		u16 result = ping_port_rover + 1;
  94
  95		for (i = 0; i < (1L << 16); i++, result++) {
  96			if (!result)
  97				result++; /* avoid zero */
  98			hlist = ping_hashslot(&ping_table, sock_net(sk),
  99					    result);
 100			ping_portaddr_for_each_entry(sk2, node, hlist) {
 101				isk2 = inet_sk(sk2);
 102
 103				if (isk2->inet_num == result)
 104					goto next_port;
 105			}
 106
 107			/* found */
 108			ping_port_rover = ident = result;
 109			break;
 110next_port:
 111			;
 112		}
 113		if (i >= (1L << 16))
 114			goto fail;
 115	} else {
 116		hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
 117		ping_portaddr_for_each_entry(sk2, node, hlist) {
 118			isk2 = inet_sk(sk2);
 119
 120			/* BUG? Why is this reuse and not reuseaddr? ping.c
 121			 * doesn't turn off SO_REUSEADDR, and it doesn't expect
 122			 * that other ping processes can steal its packets.
 123			 */
 124			if ((isk2->inet_num == ident) &&
 125			    (sk2 != sk) &&
 126			    (!sk2->sk_reuse || !sk->sk_reuse))
 127				goto fail;
 128		}
 129	}
 130
 131	pr_debug("found port/ident = %d\n", ident);
 132	isk->inet_num = ident;
 133	if (sk_unhashed(sk)) {
 134		pr_debug("was not hashed\n");
 135		sock_hold(sk);
 136		hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
 137		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 138	}
 139	write_unlock_bh(&ping_table.lock);
 140	return 0;
 141
 142fail:
 143	write_unlock_bh(&ping_table.lock);
 144	return 1;
 145}
 146EXPORT_SYMBOL_GPL(ping_get_port);
 147
 148void ping_hash(struct sock *sk)
 149{
 150	pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
 151	BUG(); /* "Please do not press this button again." */
 
 
 152}
 153
 154void ping_unhash(struct sock *sk)
 155{
 156	struct inet_sock *isk = inet_sk(sk);
 
 157	pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
 
 158	if (sk_hashed(sk)) {
 159		write_lock_bh(&ping_table.lock);
 160		hlist_nulls_del(&sk->sk_nulls_node);
 
 161		sock_put(sk);
 162		isk->inet_num = 0;
 163		isk->inet_sport = 0;
 164		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 165		write_unlock_bh(&ping_table.lock);
 166	}
 
 167}
 168EXPORT_SYMBOL_GPL(ping_unhash);
 169
 170static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
 171{
 172	struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
 173	struct sock *sk = NULL;
 174	struct inet_sock *isk;
 175	struct hlist_nulls_node *hnode;
 176	int dif = skb->dev->ifindex;
 177
 178	if (skb->protocol == htons(ETH_P_IP)) {
 179		pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
 180			 (int)ident, &ip_hdr(skb)->daddr, dif);
 181#if IS_ENABLED(CONFIG_IPV6)
 182	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 183		pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
 184			 (int)ident, &ipv6_hdr(skb)->daddr, dif);
 185#endif
 186	}
 187
 188	read_lock_bh(&ping_table.lock);
 189
 190	ping_portaddr_for_each_entry(sk, hnode, hslot) {
 191		isk = inet_sk(sk);
 192
 193		pr_debug("iterate\n");
 194		if (isk->inet_num != ident)
 195			continue;
 196
 197		if (skb->protocol == htons(ETH_P_IP) &&
 198		    sk->sk_family == AF_INET) {
 199			pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
 200				 (int) isk->inet_num, &isk->inet_rcv_saddr,
 201				 sk->sk_bound_dev_if);
 202
 203			if (isk->inet_rcv_saddr &&
 204			    isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
 205				continue;
 206#if IS_ENABLED(CONFIG_IPV6)
 207		} else if (skb->protocol == htons(ETH_P_IPV6) &&
 208			   sk->sk_family == AF_INET6) {
 209
 210			pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
 211				 (int) isk->inet_num,
 212				 &sk->sk_v6_rcv_saddr,
 213				 sk->sk_bound_dev_if);
 214
 215			if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 216			    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
 217					     &ipv6_hdr(skb)->daddr))
 218				continue;
 219#endif
 
 
 220		}
 221
 222		if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
 223			continue;
 224
 225		sock_hold(sk);
 226		goto exit;
 227	}
 228
 229	sk = NULL;
 230exit:
 231	read_unlock_bh(&ping_table.lock);
 232
 233	return sk;
 234}
 235
 236static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
 237					  kgid_t *high)
 238{
 239	kgid_t *data = net->ipv4.ping_group_range.range;
 240	unsigned int seq;
 241
 242	do {
 243		seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
 244
 245		*low = data[0];
 246		*high = data[1];
 247	} while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
 248}
 249
 250
 251int ping_init_sock(struct sock *sk)
 252{
 253	struct net *net = sock_net(sk);
 254	kgid_t group = current_egid();
 255	struct group_info *group_info;
 256	int i, j, count;
 257	kgid_t low, high;
 258	int ret = 0;
 259
 
 
 
 260	inet_get_ping_group_range_net(net, &low, &high);
 261	if (gid_lte(low, group) && gid_lte(group, high))
 262		return 0;
 263
 264	group_info = get_current_groups();
 265	count = group_info->ngroups;
 266	for (i = 0; i < group_info->nblocks; i++) {
 267		int cp_count = min_t(int, NGROUPS_PER_BLOCK, count);
 268		for (j = 0; j < cp_count; j++) {
 269			kgid_t gid = group_info->blocks[i][j];
 270			if (gid_lte(low, gid) && gid_lte(gid, high))
 271				goto out_release_group;
 272		}
 273
 274		count -= cp_count;
 
 275	}
 276
 277	ret = -EACCES;
 278
 279out_release_group:
 280	put_group_info(group_info);
 281	return ret;
 282}
 283EXPORT_SYMBOL_GPL(ping_init_sock);
 284
 285void ping_close(struct sock *sk, long timeout)
 286{
 287	pr_debug("ping_close(sk=%p,sk->num=%u)\n",
 288		 inet_sk(sk), inet_sk(sk)->inet_num);
 289	pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
 290
 291	sk_common_release(sk);
 292}
 293EXPORT_SYMBOL_GPL(ping_close);
 294
 295/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
 296static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
 297				struct sockaddr *uaddr, int addr_len) {
 298	struct net *net = sock_net(sk);
 299	if (sk->sk_family == AF_INET) {
 300		struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
 301		int chk_addr_ret;
 302
 303		if (addr_len < sizeof(*addr))
 304			return -EINVAL;
 305
 
 
 
 
 
 306		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
 307			 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
 308
 309		chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
 310
 311		if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
 312			chk_addr_ret = RTN_LOCAL;
 313
 314		if ((sysctl_ip_nonlocal_bind == 0 &&
 315		    isk->freebind == 0 && isk->transparent == 0 &&
 316		     chk_addr_ret != RTN_LOCAL) ||
 317		    chk_addr_ret == RTN_MULTICAST ||
 318		    chk_addr_ret == RTN_BROADCAST)
 319			return -EADDRNOTAVAIL;
 320
 321#if IS_ENABLED(CONFIG_IPV6)
 322	} else if (sk->sk_family == AF_INET6) {
 323		struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
 324		int addr_type, scoped, has_addr;
 325		struct net_device *dev = NULL;
 326
 327		if (addr_len < sizeof(*addr))
 328			return -EINVAL;
 329
 330		if (addr->sin6_family != AF_INET6)
 331			return -EINVAL;
 332
 333		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
 334			 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
 335
 336		addr_type = ipv6_addr_type(&addr->sin6_addr);
 337		scoped = __ipv6_addr_needs_scope_id(addr_type);
 338		if ((addr_type != IPV6_ADDR_ANY &&
 339		     !(addr_type & IPV6_ADDR_UNICAST)) ||
 340		    (scoped && !addr->sin6_scope_id))
 341			return -EINVAL;
 342
 343		rcu_read_lock();
 344		if (addr->sin6_scope_id) {
 345			dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
 346			if (!dev) {
 347				rcu_read_unlock();
 348				return -ENODEV;
 349			}
 350		}
 351		has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
 352						    scoped);
 353		rcu_read_unlock();
 354
 355		if (!(isk->freebind || isk->transparent || has_addr ||
 356		      addr_type == IPV6_ADDR_ANY))
 357			return -EADDRNOTAVAIL;
 358
 359		if (scoped)
 360			sk->sk_bound_dev_if = addr->sin6_scope_id;
 361#endif
 362	} else {
 363		return -EAFNOSUPPORT;
 364	}
 365	return 0;
 366}
 367
 368static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
 369{
 370	if (saddr->sa_family == AF_INET) {
 371		struct inet_sock *isk = inet_sk(sk);
 372		struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
 373		isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
 374#if IS_ENABLED(CONFIG_IPV6)
 375	} else if (saddr->sa_family == AF_INET6) {
 376		struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
 377		struct ipv6_pinfo *np = inet6_sk(sk);
 378		sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
 379#endif
 380	}
 381}
 382
 383static void ping_clear_saddr(struct sock *sk, int dif)
 384{
 385	sk->sk_bound_dev_if = dif;
 386	if (sk->sk_family == AF_INET) {
 387		struct inet_sock *isk = inet_sk(sk);
 388		isk->inet_rcv_saddr = isk->inet_saddr = 0;
 389#if IS_ENABLED(CONFIG_IPV6)
 390	} else if (sk->sk_family == AF_INET6) {
 391		struct ipv6_pinfo *np = inet6_sk(sk);
 392		memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
 393		memset(&np->saddr, 0, sizeof(np->saddr));
 394#endif
 395	}
 396}
 397/*
 398 * We need our own bind because there are no privileged id's == local ports.
 399 * Moreover, we don't allow binding to multi- and broadcast addresses.
 400 */
 401
 402int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 403{
 404	struct inet_sock *isk = inet_sk(sk);
 405	unsigned short snum;
 406	int err;
 407	int dif = sk->sk_bound_dev_if;
 408
 409	err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
 410	if (err)
 411		return err;
 412
 413	lock_sock(sk);
 414
 415	err = -EINVAL;
 416	if (isk->inet_num != 0)
 417		goto out;
 418
 419	err = -EADDRINUSE;
 420	ping_set_saddr(sk, uaddr);
 421	snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
 422	if (ping_get_port(sk, snum) != 0) {
 423		ping_clear_saddr(sk, dif);
 424		goto out;
 425	}
 426
 427	pr_debug("after bind(): num = %d, dif = %d\n",
 428		 (int)isk->inet_num,
 429		 (int)sk->sk_bound_dev_if);
 430
 431	err = 0;
 432	if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
 433		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 434#if IS_ENABLED(CONFIG_IPV6)
 435	if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 436		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 437#endif
 438
 439	if (snum)
 440		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 441	isk->inet_sport = htons(isk->inet_num);
 442	isk->inet_daddr = 0;
 443	isk->inet_dport = 0;
 444
 445#if IS_ENABLED(CONFIG_IPV6)
 446	if (sk->sk_family == AF_INET6)
 447		memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
 448#endif
 449
 450	sk_dst_reset(sk);
 451out:
 452	release_sock(sk);
 453	pr_debug("ping_v4_bind -> %d\n", err);
 454	return err;
 455}
 456EXPORT_SYMBOL_GPL(ping_bind);
 457
 458/*
 459 * Is this a supported type of ICMP message?
 460 */
 461
 462static inline int ping_supported(int family, int type, int code)
 463{
 464	return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
 465	       (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
 466}
 467
 468/*
 469 * This routine is called by the ICMP module when it gets some
 470 * sort of error condition.
 471 */
 472
 473void ping_err(struct sk_buff *skb, int offset, u32 info)
 474{
 475	int family;
 476	struct icmphdr *icmph;
 477	struct inet_sock *inet_sock;
 478	int type;
 479	int code;
 480	struct net *net = dev_net(skb->dev);
 481	struct sock *sk;
 482	int harderr;
 483	int err;
 484
 485	if (skb->protocol == htons(ETH_P_IP)) {
 486		family = AF_INET;
 487		type = icmp_hdr(skb)->type;
 488		code = icmp_hdr(skb)->code;
 489		icmph = (struct icmphdr *)(skb->data + offset);
 490	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 491		family = AF_INET6;
 492		type = icmp6_hdr(skb)->icmp6_type;
 493		code = icmp6_hdr(skb)->icmp6_code;
 494		icmph = (struct icmphdr *) (skb->data + offset);
 495	} else {
 496		BUG();
 497	}
 498
 499	/* We assume the packet has already been checked by icmp_unreach */
 500
 501	if (!ping_supported(family, icmph->type, icmph->code))
 502		return;
 503
 504	pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
 505		 skb->protocol, type, code, ntohs(icmph->un.echo.id),
 506		 ntohs(icmph->un.echo.sequence));
 507
 508	sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 509	if (sk == NULL) {
 510		pr_debug("no socket, dropping\n");
 511		return;	/* No socket for error */
 512	}
 513	pr_debug("err on socket %p\n", sk);
 514
 515	err = 0;
 516	harderr = 0;
 517	inet_sock = inet_sk(sk);
 518
 519	if (skb->protocol == htons(ETH_P_IP)) {
 520		switch (type) {
 521		default:
 522		case ICMP_TIME_EXCEEDED:
 523			err = EHOSTUNREACH;
 524			break;
 525		case ICMP_SOURCE_QUENCH:
 526			/* This is not a real error but ping wants to see it.
 527			 * Report it with some fake errno.
 528			 */
 529			err = EREMOTEIO;
 530			break;
 531		case ICMP_PARAMETERPROB:
 532			err = EPROTO;
 533			harderr = 1;
 534			break;
 535		case ICMP_DEST_UNREACH:
 536			if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
 537				ipv4_sk_update_pmtu(skb, sk, info);
 538				if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
 539					err = EMSGSIZE;
 540					harderr = 1;
 541					break;
 542				}
 543				goto out;
 544			}
 545			err = EHOSTUNREACH;
 546			if (code <= NR_ICMP_UNREACH) {
 547				harderr = icmp_err_convert[code].fatal;
 548				err = icmp_err_convert[code].errno;
 549			}
 550			break;
 551		case ICMP_REDIRECT:
 552			/* See ICMP_SOURCE_QUENCH */
 553			ipv4_sk_redirect(skb, sk);
 554			err = EREMOTEIO;
 555			break;
 556		}
 557#if IS_ENABLED(CONFIG_IPV6)
 558	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 559		harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
 560#endif
 561	}
 562
 563	/*
 564	 *      RFC1122: OK.  Passes ICMP errors back to application, as per
 565	 *	4.1.3.3.
 566	 */
 567	if ((family == AF_INET && !inet_sock->recverr) ||
 568	    (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
 569		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 570			goto out;
 571	} else {
 572		if (family == AF_INET) {
 573			ip_icmp_error(sk, skb, err, 0 /* no remote port */,
 574				      info, (u8 *)icmph);
 575#if IS_ENABLED(CONFIG_IPV6)
 576		} else if (family == AF_INET6) {
 577			pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
 578						   info, (u8 *)icmph);
 579#endif
 580		}
 581	}
 582	sk->sk_err = err;
 583	sk->sk_error_report(sk);
 584out:
 585	sock_put(sk);
 586}
 587EXPORT_SYMBOL_GPL(ping_err);
 588
 589/*
 590 *	Copy and checksum an ICMP Echo packet from user space into a buffer
 591 *	starting from the payload.
 592 */
 593
 594int ping_getfrag(void *from, char *to,
 595		 int offset, int fraglen, int odd, struct sk_buff *skb)
 596{
 597	struct pingfakehdr *pfh = (struct pingfakehdr *)from;
 598
 599	if (offset == 0) {
 600		if (fraglen < sizeof(struct icmphdr))
 
 601			BUG();
 602		if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
 603			    pfh->iov, 0, fraglen - sizeof(struct icmphdr),
 604			    &pfh->wcheck))
 605			return -EFAULT;
 606	} else if (offset < sizeof(struct icmphdr)) {
 607			BUG();
 608	} else {
 609		if (csum_partial_copy_fromiovecend
 610				(to, pfh->iov, offset - sizeof(struct icmphdr),
 611				 fraglen, &pfh->wcheck))
 612			return -EFAULT;
 613	}
 614
 615#if IS_ENABLED(CONFIG_IPV6)
 616	/* For IPv6, checksum each skb as we go along, as expected by
 617	 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
 618	 * wcheck, it will be finalized in ping_v4_push_pending_frames.
 619	 */
 620	if (pfh->family == AF_INET6) {
 621		skb->csum = pfh->wcheck;
 622		skb->ip_summed = CHECKSUM_NONE;
 623		pfh->wcheck = 0;
 624	}
 625#endif
 626
 627	return 0;
 628}
 629EXPORT_SYMBOL_GPL(ping_getfrag);
 630
 631static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
 632				       struct flowi4 *fl4)
 633{
 634	struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
 635
 
 
 636	pfh->wcheck = csum_partial((char *)&pfh->icmph,
 637		sizeof(struct icmphdr), pfh->wcheck);
 638	pfh->icmph.checksum = csum_fold(pfh->wcheck);
 639	memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
 640	skb->ip_summed = CHECKSUM_NONE;
 641	return ip_push_pending_frames(sk, fl4);
 642}
 643
 644int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
 645			void *user_icmph, size_t icmph_len) {
 646	u8 type, code;
 647
 648	if (len > 0xFFFF)
 649		return -EMSGSIZE;
 650
 
 
 
 
 651	/*
 652	 *	Check the flags.
 653	 */
 654
 655	/* Mirror BSD error message compatibility */
 656	if (msg->msg_flags & MSG_OOB)
 657		return -EOPNOTSUPP;
 658
 659	/*
 660	 *	Fetch the ICMP header provided by the userland.
 661	 *	iovec is modified! The ICMP header is consumed.
 662	 */
 663	if (memcpy_fromiovec(user_icmph, msg->msg_iov, icmph_len))
 664		return -EFAULT;
 665
 666	if (family == AF_INET) {
 667		type = ((struct icmphdr *) user_icmph)->type;
 668		code = ((struct icmphdr *) user_icmph)->code;
 669#if IS_ENABLED(CONFIG_IPV6)
 670	} else if (family == AF_INET6) {
 671		type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
 672		code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
 673#endif
 674	} else {
 675		BUG();
 676	}
 677
 678	if (!ping_supported(family, type, code))
 679		return -EINVAL;
 680
 681	return 0;
 682}
 683EXPORT_SYMBOL_GPL(ping_common_sendmsg);
 684
 685static int ping_v4_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 686			   size_t len)
 687{
 688	struct net *net = sock_net(sk);
 689	struct flowi4 fl4;
 690	struct inet_sock *inet = inet_sk(sk);
 691	struct ipcm_cookie ipc;
 692	struct icmphdr user_icmph;
 693	struct pingfakehdr pfh;
 694	struct rtable *rt = NULL;
 695	struct ip_options_data opt_copy;
 696	int free = 0;
 697	__be32 saddr, daddr, faddr;
 698	u8  tos;
 699	int err;
 700
 701	pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
 702
 703	err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
 704				  sizeof(user_icmph));
 705	if (err)
 706		return err;
 707
 708	/*
 709	 *	Get and verify the address.
 710	 */
 711
 712	if (msg->msg_name) {
 713		DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
 714		if (msg->msg_namelen < sizeof(*usin))
 715			return -EINVAL;
 716		if (usin->sin_family != AF_INET)
 717			return -EINVAL;
 718		daddr = usin->sin_addr.s_addr;
 719		/* no remote port */
 720	} else {
 721		if (sk->sk_state != TCP_ESTABLISHED)
 722			return -EDESTADDRREQ;
 723		daddr = inet->inet_daddr;
 724		/* no remote port */
 725	}
 726
 727	ipc.addr = inet->inet_saddr;
 728	ipc.opt = NULL;
 729	ipc.oif = sk->sk_bound_dev_if;
 730	ipc.tx_flags = 0;
 731	ipc.ttl = 0;
 732	ipc.tos = -1;
 733
 734	sock_tx_timestamp(sk, &ipc.tx_flags);
 735
 736	if (msg->msg_controllen) {
 737		err = ip_cmsg_send(sock_net(sk), msg, &ipc, false);
 738		if (err)
 
 739			return err;
 
 740		if (ipc.opt)
 741			free = 1;
 742	}
 743	if (!ipc.opt) {
 744		struct ip_options_rcu *inet_opt;
 745
 746		rcu_read_lock();
 747		inet_opt = rcu_dereference(inet->inet_opt);
 748		if (inet_opt) {
 749			memcpy(&opt_copy, inet_opt,
 750			       sizeof(*inet_opt) + inet_opt->opt.optlen);
 751			ipc.opt = &opt_copy.opt;
 752		}
 753		rcu_read_unlock();
 754	}
 755
 756	saddr = ipc.addr;
 757	ipc.addr = faddr = daddr;
 758
 759	if (ipc.opt && ipc.opt->opt.srr) {
 760		if (!daddr)
 761			return -EINVAL;
 
 
 762		faddr = ipc.opt->opt.faddr;
 763	}
 764	tos = get_rttos(&ipc, inet);
 765	if (sock_flag(sk, SOCK_LOCALROUTE) ||
 766	    (msg->msg_flags & MSG_DONTROUTE) ||
 767	    (ipc.opt && ipc.opt->opt.is_strictroute)) {
 768		tos |= RTO_ONLINK;
 769	}
 770
 771	if (ipv4_is_multicast(daddr)) {
 772		if (!ipc.oif)
 773			ipc.oif = inet->mc_index;
 774		if (!saddr)
 775			saddr = inet->mc_addr;
 776	} else if (!ipc.oif)
 777		ipc.oif = inet->uc_index;
 778
 779	flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
 780			   RT_SCOPE_UNIVERSE, sk->sk_protocol,
 781			   inet_sk_flowi_flags(sk), faddr, saddr, 0, 0);
 
 
 
 
 782
 783	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
 784	rt = ip_route_output_flow(net, &fl4, sk);
 785	if (IS_ERR(rt)) {
 786		err = PTR_ERR(rt);
 787		rt = NULL;
 788		if (err == -ENETUNREACH)
 789			IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
 790		goto out;
 791	}
 792
 793	err = -EACCES;
 794	if ((rt->rt_flags & RTCF_BROADCAST) &&
 795	    !sock_flag(sk, SOCK_BROADCAST))
 796		goto out;
 797
 798	if (msg->msg_flags & MSG_CONFIRM)
 799		goto do_confirm;
 800back_from_confirm:
 801
 802	if (!ipc.addr)
 803		ipc.addr = fl4.daddr;
 804
 805	lock_sock(sk);
 806
 807	pfh.icmph.type = user_icmph.type; /* already checked */
 808	pfh.icmph.code = user_icmph.code; /* ditto */
 809	pfh.icmph.checksum = 0;
 810	pfh.icmph.un.echo.id = inet->inet_sport;
 811	pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
 812	pfh.iov = msg->msg_iov;
 813	pfh.wcheck = 0;
 814	pfh.family = AF_INET;
 815
 816	err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
 817			0, &ipc, &rt, msg->msg_flags);
 818	if (err)
 819		ip_flush_pending_frames(sk);
 820	else
 821		err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
 822	release_sock(sk);
 823
 824out:
 825	ip_rt_put(rt);
 
 826	if (free)
 827		kfree(ipc.opt);
 828	if (!err) {
 829		icmp_out_count(sock_net(sk), user_icmph.type);
 830		return len;
 831	}
 832	return err;
 833
 834do_confirm:
 835	dst_confirm(&rt->dst);
 
 836	if (!(msg->msg_flags & MSG_PROBE) || len)
 837		goto back_from_confirm;
 838	err = 0;
 839	goto out;
 840}
 841
 842int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 843		 size_t len, int noblock, int flags, int *addr_len)
 844{
 845	struct inet_sock *isk = inet_sk(sk);
 846	int family = sk->sk_family;
 847	struct sk_buff *skb;
 848	int copied, err;
 849
 850	pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
 851
 852	err = -EOPNOTSUPP;
 853	if (flags & MSG_OOB)
 854		goto out;
 855
 856	if (flags & MSG_ERRQUEUE) {
 857		if (family == AF_INET) {
 858			return ip_recv_error(sk, msg, len, addr_len);
 859#if IS_ENABLED(CONFIG_IPV6)
 860		} else if (family == AF_INET6) {
 861			return pingv6_ops.ipv6_recv_error(sk, msg, len,
 862							  addr_len);
 863#endif
 864		}
 865	}
 866
 867	skb = skb_recv_datagram(sk, flags, noblock, &err);
 868	if (!skb)
 869		goto out;
 870
 871	copied = skb->len;
 872	if (copied > len) {
 873		msg->msg_flags |= MSG_TRUNC;
 874		copied = len;
 875	}
 876
 877	/* Don't bother checking the checksum */
 878	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 879	if (err)
 880		goto done;
 881
 882	sock_recv_timestamp(msg, sk, skb);
 883
 884	/* Copy the address and add cmsg data. */
 885	if (family == AF_INET) {
 886		DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
 887
 888		if (sin) {
 889			sin->sin_family = AF_INET;
 890			sin->sin_port = 0 /* skb->h.uh->source */;
 891			sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 892			memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 893			*addr_len = sizeof(*sin);
 894		}
 895
 896		if (isk->cmsg_flags)
 897			ip_cmsg_recv(msg, skb);
 898
 899#if IS_ENABLED(CONFIG_IPV6)
 900	} else if (family == AF_INET6) {
 901		struct ipv6_pinfo *np = inet6_sk(sk);
 902		struct ipv6hdr *ip6 = ipv6_hdr(skb);
 903		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 904
 905		if (sin6) {
 906			sin6->sin6_family = AF_INET6;
 907			sin6->sin6_port = 0;
 908			sin6->sin6_addr = ip6->saddr;
 909			sin6->sin6_flowinfo = 0;
 910			if (np->sndflow)
 911				sin6->sin6_flowinfo = ip6_flowinfo(ip6);
 912			sin6->sin6_scope_id =
 913				ipv6_iface_scope_id(&sin6->sin6_addr,
 914						    IP6CB(skb)->iif);
 915			*addr_len = sizeof(*sin6);
 916		}
 917
 918		if (inet6_sk(sk)->rxopt.all)
 919			pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
 920		if (skb->protocol == htons(ETH_P_IPV6) &&
 921		    inet6_sk(sk)->rxopt.all)
 922			pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
 923		else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
 924			ip_cmsg_recv(msg, skb);
 925#endif
 926	} else {
 927		BUG();
 928	}
 929
 930	err = copied;
 931
 932done:
 933	skb_free_datagram(sk, skb);
 934out:
 935	pr_debug("ping_recvmsg -> %d\n", err);
 936	return err;
 937}
 938EXPORT_SYMBOL_GPL(ping_recvmsg);
 939
 940int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 941{
 942	pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
 943		 inet_sk(sk), inet_sk(sk)->inet_num, skb);
 944	if (sock_queue_rcv_skb(sk, skb) < 0) {
 945		kfree_skb(skb);
 946		pr_debug("ping_queue_rcv_skb -> failed\n");
 947		return -1;
 948	}
 949	return 0;
 950}
 951EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
 952
 953
 954/*
 955 *	All we need to do is get the socket.
 956 */
 957
 958void ping_rcv(struct sk_buff *skb)
 959{
 960	struct sock *sk;
 961	struct net *net = dev_net(skb->dev);
 962	struct icmphdr *icmph = icmp_hdr(skb);
 963
 964	/* We assume the packet has already been checked by icmp_rcv */
 965
 966	pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
 967		 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
 968
 969	/* Push ICMP header back */
 970	skb_push(skb, skb->data - (u8 *)icmph);
 971
 972	sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 973	if (sk != NULL) {
 
 
 974		pr_debug("rcv on socket %p\n", sk);
 975		ping_queue_rcv_skb(sk, skb_get(skb));
 
 976		sock_put(sk);
 977		return;
 978	}
 979	pr_debug("no socket, dropping\n");
 980
 981	/* We're called from icmp_rcv(). kfree_skb() is done there. */
 982}
 983EXPORT_SYMBOL_GPL(ping_rcv);
 984
 985struct proto ping_prot = {
 986	.name =		"PING",
 987	.owner =	THIS_MODULE,
 988	.init =		ping_init_sock,
 989	.close =	ping_close,
 990	.connect =	ip4_datagram_connect,
 991	.disconnect =	udp_disconnect,
 992	.setsockopt =	ip_setsockopt,
 993	.getsockopt =	ip_getsockopt,
 994	.sendmsg =	ping_v4_sendmsg,
 995	.recvmsg =	ping_recvmsg,
 996	.bind =		ping_bind,
 997	.backlog_rcv =	ping_queue_rcv_skb,
 998	.release_cb =	ip4_datagram_release_cb,
 999	.hash =		ping_hash,
1000	.unhash =	ping_unhash,
1001	.get_port =	ping_get_port,
1002	.obj_size =	sizeof(struct inet_sock),
1003};
1004EXPORT_SYMBOL(ping_prot);
1005
1006#ifdef CONFIG_PROC_FS
1007
1008static struct sock *ping_get_first(struct seq_file *seq, int start)
1009{
1010	struct sock *sk;
1011	struct ping_iter_state *state = seq->private;
1012	struct net *net = seq_file_net(seq);
1013
1014	for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1015	     ++state->bucket) {
1016		struct hlist_nulls_node *node;
1017		struct hlist_nulls_head *hslot;
1018
1019		hslot = &ping_table.hash[state->bucket];
1020
1021		if (hlist_nulls_empty(hslot))
1022			continue;
1023
1024		sk_nulls_for_each(sk, node, hslot) {
1025			if (net_eq(sock_net(sk), net) &&
1026			    sk->sk_family == state->family)
1027				goto found;
1028		}
1029	}
1030	sk = NULL;
1031found:
1032	return sk;
1033}
1034
1035static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1036{
1037	struct ping_iter_state *state = seq->private;
1038	struct net *net = seq_file_net(seq);
1039
1040	do {
1041		sk = sk_nulls_next(sk);
1042	} while (sk && (!net_eq(sock_net(sk), net)));
1043
1044	if (!sk)
1045		return ping_get_first(seq, state->bucket + 1);
1046	return sk;
1047}
1048
1049static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1050{
1051	struct sock *sk = ping_get_first(seq, 0);
1052
1053	if (sk)
1054		while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1055			--pos;
1056	return pos ? NULL : sk;
1057}
1058
1059void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
 
1060{
1061	struct ping_iter_state *state = seq->private;
1062	state->bucket = 0;
1063	state->family = family;
1064
1065	read_lock_bh(&ping_table.lock);
1066
1067	return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1068}
1069EXPORT_SYMBOL_GPL(ping_seq_start);
1070
1071static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1072{
1073	return ping_seq_start(seq, pos, AF_INET);
1074}
1075
1076void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1077{
1078	struct sock *sk;
1079
1080	if (v == SEQ_START_TOKEN)
1081		sk = ping_get_idx(seq, 0);
1082	else
1083		sk = ping_get_next(seq, v);
1084
1085	++*pos;
1086	return sk;
1087}
1088EXPORT_SYMBOL_GPL(ping_seq_next);
1089
1090void ping_seq_stop(struct seq_file *seq, void *v)
 
1091{
1092	read_unlock_bh(&ping_table.lock);
1093}
1094EXPORT_SYMBOL_GPL(ping_seq_stop);
1095
1096static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1097		int bucket)
1098{
1099	struct inet_sock *inet = inet_sk(sp);
1100	__be32 dest = inet->inet_daddr;
1101	__be32 src = inet->inet_rcv_saddr;
1102	__u16 destp = ntohs(inet->inet_dport);
1103	__u16 srcp = ntohs(inet->inet_sport);
1104
1105	seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1106		" %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
1107		bucket, src, srcp, dest, destp, sp->sk_state,
1108		sk_wmem_alloc_get(sp),
1109		sk_rmem_alloc_get(sp),
1110		0, 0L, 0,
1111		from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1112		0, sock_i_ino(sp),
1113		atomic_read(&sp->sk_refcnt), sp,
1114		atomic_read(&sp->sk_drops));
1115}
1116
1117static int ping_v4_seq_show(struct seq_file *seq, void *v)
1118{
1119	seq_setwidth(seq, 127);
1120	if (v == SEQ_START_TOKEN)
1121		seq_puts(seq, "  sl  local_address rem_address   st tx_queue "
1122			   "rx_queue tr tm->when retrnsmt   uid  timeout "
1123			   "inode ref pointer drops");
1124	else {
1125		struct ping_iter_state *state = seq->private;
1126
1127		ping_v4_format_sock(v, seq, state->bucket);
1128	}
1129	seq_pad(seq, '\n');
1130	return 0;
1131}
1132
1133static const struct seq_operations ping_v4_seq_ops = {
1134	.show		= ping_v4_seq_show,
1135	.start		= ping_v4_seq_start,
 
1136	.next		= ping_seq_next,
1137	.stop		= ping_seq_stop,
1138};
1139
1140static int ping_seq_open(struct inode *inode, struct file *file)
1141{
1142	struct ping_seq_afinfo *afinfo = PDE_DATA(inode);
1143	return seq_open_net(inode, file, &afinfo->seq_ops,
1144			   sizeof(struct ping_iter_state));
1145}
1146
1147const struct file_operations ping_seq_fops = {
1148	.open		= ping_seq_open,
1149	.read		= seq_read,
1150	.llseek		= seq_lseek,
1151	.release	= seq_release_net,
1152};
1153EXPORT_SYMBOL_GPL(ping_seq_fops);
1154
1155static struct ping_seq_afinfo ping_v4_seq_afinfo = {
1156	.name		= "icmp",
1157	.family		= AF_INET,
1158	.seq_fops	= &ping_seq_fops,
1159	.seq_ops	= {
1160		.start		= ping_v4_seq_start,
1161		.show		= ping_v4_seq_show,
1162		.next		= ping_seq_next,
1163		.stop		= ping_seq_stop,
1164	},
1165};
1166
1167int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
1168{
1169	struct proc_dir_entry *p;
1170	p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1171			     afinfo->seq_fops, afinfo);
1172	if (!p)
1173		return -ENOMEM;
1174	return 0;
1175}
1176EXPORT_SYMBOL_GPL(ping_proc_register);
1177
1178void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
1179{
1180	remove_proc_entry(afinfo->name, net->proc_net);
1181}
1182EXPORT_SYMBOL_GPL(ping_proc_unregister);
1183
1184static int __net_init ping_v4_proc_init_net(struct net *net)
1185{
1186	return ping_proc_register(net, &ping_v4_seq_afinfo);
1187}
1188
1189static void __net_exit ping_v4_proc_exit_net(struct net *net)
1190{
1191	ping_proc_unregister(net, &ping_v4_seq_afinfo);
1192}
1193
1194static struct pernet_operations ping_v4_net_ops = {
1195	.init = ping_v4_proc_init_net,
1196	.exit = ping_v4_proc_exit_net,
1197};
1198
1199int __init ping_proc_init(void)
1200{
1201	return register_pernet_subsys(&ping_v4_net_ops);
1202}
1203
1204void ping_proc_exit(void)
1205{
1206	unregister_pernet_subsys(&ping_v4_net_ops);
1207}
1208
1209#endif
1210
1211void __init ping_init(void)
1212{
1213	int i;
1214
1215	for (i = 0; i < PING_HTABLE_SIZE; i++)
1216		INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1217	rwlock_init(&ping_table.lock);
1218}
v5.9
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   4 *		operating system.  INET is implemented using the  BSD Socket
   5 *		interface as the means of communication with the user level.
   6 *
   7 *		"Ping" sockets
   8 *
 
 
 
 
 
   9 * Based on ipv4/udp.c code.
  10 *
  11 * Authors:	Vasiliy Kulikov / Openwall (for Linux 2.6),
  12 *		Pavel Kankovsky (for Linux 2.4.32)
  13 *
  14 * Pavel gave all rights to bugs to Vasiliy,
  15 * none of the bugs are Pavel's now.
 
  16 */
  17
  18#include <linux/uaccess.h>
  19#include <linux/types.h>
  20#include <linux/fcntl.h>
  21#include <linux/socket.h>
  22#include <linux/sockios.h>
  23#include <linux/in.h>
  24#include <linux/errno.h>
  25#include <linux/timer.h>
  26#include <linux/mm.h>
  27#include <linux/inet.h>
  28#include <linux/netdevice.h>
  29#include <net/snmp.h>
  30#include <net/ip.h>
  31#include <net/icmp.h>
  32#include <net/protocol.h>
  33#include <linux/skbuff.h>
  34#include <linux/proc_fs.h>
  35#include <linux/export.h>
  36#include <net/sock.h>
  37#include <net/ping.h>
  38#include <net/udp.h>
  39#include <net/route.h>
  40#include <net/inet_common.h>
  41#include <net/checksum.h>
  42
  43#if IS_ENABLED(CONFIG_IPV6)
  44#include <linux/in6.h>
  45#include <linux/icmpv6.h>
  46#include <net/addrconf.h>
  47#include <net/ipv6.h>
  48#include <net/transp_v6.h>
  49#endif
  50
  51struct ping_table {
  52	struct hlist_nulls_head	hash[PING_HTABLE_SIZE];
  53	rwlock_t		lock;
  54};
  55
  56static struct ping_table ping_table;
  57struct pingv6_ops pingv6_ops;
  58EXPORT_SYMBOL_GPL(pingv6_ops);
  59
  60static u16 ping_port_rover;
  61
  62static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
  63{
  64	u32 res = (num + net_hash_mix(net)) & mask;
  65
  66	pr_debug("hash(%u) = %u\n", num, res);
  67	return res;
  68}
  69EXPORT_SYMBOL_GPL(ping_hash);
  70
  71static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
  72					     struct net *net, unsigned int num)
  73{
  74	return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
  75}
  76
  77int ping_get_port(struct sock *sk, unsigned short ident)
  78{
  79	struct hlist_nulls_node *node;
  80	struct hlist_nulls_head *hlist;
  81	struct inet_sock *isk, *isk2;
  82	struct sock *sk2 = NULL;
  83
  84	isk = inet_sk(sk);
  85	write_lock_bh(&ping_table.lock);
  86	if (ident == 0) {
  87		u32 i;
  88		u16 result = ping_port_rover + 1;
  89
  90		for (i = 0; i < (1L << 16); i++, result++) {
  91			if (!result)
  92				result++; /* avoid zero */
  93			hlist = ping_hashslot(&ping_table, sock_net(sk),
  94					    result);
  95			ping_portaddr_for_each_entry(sk2, node, hlist) {
  96				isk2 = inet_sk(sk2);
  97
  98				if (isk2->inet_num == result)
  99					goto next_port;
 100			}
 101
 102			/* found */
 103			ping_port_rover = ident = result;
 104			break;
 105next_port:
 106			;
 107		}
 108		if (i >= (1L << 16))
 109			goto fail;
 110	} else {
 111		hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
 112		ping_portaddr_for_each_entry(sk2, node, hlist) {
 113			isk2 = inet_sk(sk2);
 114
 115			/* BUG? Why is this reuse and not reuseaddr? ping.c
 116			 * doesn't turn off SO_REUSEADDR, and it doesn't expect
 117			 * that other ping processes can steal its packets.
 118			 */
 119			if ((isk2->inet_num == ident) &&
 120			    (sk2 != sk) &&
 121			    (!sk2->sk_reuse || !sk->sk_reuse))
 122				goto fail;
 123		}
 124	}
 125
 126	pr_debug("found port/ident = %d\n", ident);
 127	isk->inet_num = ident;
 128	if (sk_unhashed(sk)) {
 129		pr_debug("was not hashed\n");
 130		sock_hold(sk);
 131		hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
 132		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 133	}
 134	write_unlock_bh(&ping_table.lock);
 135	return 0;
 136
 137fail:
 138	write_unlock_bh(&ping_table.lock);
 139	return 1;
 140}
 141EXPORT_SYMBOL_GPL(ping_get_port);
 142
 143int ping_hash(struct sock *sk)
 144{
 145	pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
 146	BUG(); /* "Please do not press this button again." */
 147
 148	return 0;
 149}
 150
 151void ping_unhash(struct sock *sk)
 152{
 153	struct inet_sock *isk = inet_sk(sk);
 154
 155	pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
 156	write_lock_bh(&ping_table.lock);
 157	if (sk_hashed(sk)) {
 
 158		hlist_nulls_del(&sk->sk_nulls_node);
 159		sk_nulls_node_init(&sk->sk_nulls_node);
 160		sock_put(sk);
 161		isk->inet_num = 0;
 162		isk->inet_sport = 0;
 163		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 
 164	}
 165	write_unlock_bh(&ping_table.lock);
 166}
 167EXPORT_SYMBOL_GPL(ping_unhash);
 168
 169static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
 170{
 171	struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
 172	struct sock *sk = NULL;
 173	struct inet_sock *isk;
 174	struct hlist_nulls_node *hnode;
 175	int dif = skb->dev->ifindex;
 176
 177	if (skb->protocol == htons(ETH_P_IP)) {
 178		pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
 179			 (int)ident, &ip_hdr(skb)->daddr, dif);
 180#if IS_ENABLED(CONFIG_IPV6)
 181	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 182		pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
 183			 (int)ident, &ipv6_hdr(skb)->daddr, dif);
 184#endif
 185	}
 186
 187	read_lock_bh(&ping_table.lock);
 188
 189	ping_portaddr_for_each_entry(sk, hnode, hslot) {
 190		isk = inet_sk(sk);
 191
 192		pr_debug("iterate\n");
 193		if (isk->inet_num != ident)
 194			continue;
 195
 196		if (skb->protocol == htons(ETH_P_IP) &&
 197		    sk->sk_family == AF_INET) {
 198			pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
 199				 (int) isk->inet_num, &isk->inet_rcv_saddr,
 200				 sk->sk_bound_dev_if);
 201
 202			if (isk->inet_rcv_saddr &&
 203			    isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
 204				continue;
 205#if IS_ENABLED(CONFIG_IPV6)
 206		} else if (skb->protocol == htons(ETH_P_IPV6) &&
 207			   sk->sk_family == AF_INET6) {
 208
 209			pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
 210				 (int) isk->inet_num,
 211				 &sk->sk_v6_rcv_saddr,
 212				 sk->sk_bound_dev_if);
 213
 214			if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
 215			    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
 216					     &ipv6_hdr(skb)->daddr))
 217				continue;
 218#endif
 219		} else {
 220			continue;
 221		}
 222
 223		if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
 224			continue;
 225
 226		sock_hold(sk);
 227		goto exit;
 228	}
 229
 230	sk = NULL;
 231exit:
 232	read_unlock_bh(&ping_table.lock);
 233
 234	return sk;
 235}
 236
 237static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
 238					  kgid_t *high)
 239{
 240	kgid_t *data = net->ipv4.ping_group_range.range;
 241	unsigned int seq;
 242
 243	do {
 244		seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
 245
 246		*low = data[0];
 247		*high = data[1];
 248	} while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
 249}
 250
 251
 252int ping_init_sock(struct sock *sk)
 253{
 254	struct net *net = sock_net(sk);
 255	kgid_t group = current_egid();
 256	struct group_info *group_info;
 257	int i;
 258	kgid_t low, high;
 259	int ret = 0;
 260
 261	if (sk->sk_family == AF_INET6)
 262		sk->sk_ipv6only = 1;
 263
 264	inet_get_ping_group_range_net(net, &low, &high);
 265	if (gid_lte(low, group) && gid_lte(group, high))
 266		return 0;
 267
 268	group_info = get_current_groups();
 269	for (i = 0; i < group_info->ngroups; i++) {
 270		kgid_t gid = group_info->gid[i];
 
 
 
 
 
 
 271
 272		if (gid_lte(low, gid) && gid_lte(gid, high))
 273			goto out_release_group;
 274	}
 275
 276	ret = -EACCES;
 277
 278out_release_group:
 279	put_group_info(group_info);
 280	return ret;
 281}
 282EXPORT_SYMBOL_GPL(ping_init_sock);
 283
 284void ping_close(struct sock *sk, long timeout)
 285{
 286	pr_debug("ping_close(sk=%p,sk->num=%u)\n",
 287		 inet_sk(sk), inet_sk(sk)->inet_num);
 288	pr_debug("isk->refcnt = %d\n", refcount_read(&sk->sk_refcnt));
 289
 290	sk_common_release(sk);
 291}
 292EXPORT_SYMBOL_GPL(ping_close);
 293
 294/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
 295static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
 296				struct sockaddr *uaddr, int addr_len) {
 297	struct net *net = sock_net(sk);
 298	if (sk->sk_family == AF_INET) {
 299		struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
 300		int chk_addr_ret;
 301
 302		if (addr_len < sizeof(*addr))
 303			return -EINVAL;
 304
 305		if (addr->sin_family != AF_INET &&
 306		    !(addr->sin_family == AF_UNSPEC &&
 307		      addr->sin_addr.s_addr == htonl(INADDR_ANY)))
 308			return -EAFNOSUPPORT;
 309
 310		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
 311			 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
 312
 313		chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
 314
 315		if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
 316			chk_addr_ret = RTN_LOCAL;
 317
 318		if ((!inet_can_nonlocal_bind(net, isk) &&
 
 319		     chk_addr_ret != RTN_LOCAL) ||
 320		    chk_addr_ret == RTN_MULTICAST ||
 321		    chk_addr_ret == RTN_BROADCAST)
 322			return -EADDRNOTAVAIL;
 323
 324#if IS_ENABLED(CONFIG_IPV6)
 325	} else if (sk->sk_family == AF_INET6) {
 326		struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
 327		int addr_type, scoped, has_addr;
 328		struct net_device *dev = NULL;
 329
 330		if (addr_len < sizeof(*addr))
 331			return -EINVAL;
 332
 333		if (addr->sin6_family != AF_INET6)
 334			return -EAFNOSUPPORT;
 335
 336		pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
 337			 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
 338
 339		addr_type = ipv6_addr_type(&addr->sin6_addr);
 340		scoped = __ipv6_addr_needs_scope_id(addr_type);
 341		if ((addr_type != IPV6_ADDR_ANY &&
 342		     !(addr_type & IPV6_ADDR_UNICAST)) ||
 343		    (scoped && !addr->sin6_scope_id))
 344			return -EINVAL;
 345
 346		rcu_read_lock();
 347		if (addr->sin6_scope_id) {
 348			dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
 349			if (!dev) {
 350				rcu_read_unlock();
 351				return -ENODEV;
 352			}
 353		}
 354		has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
 355						    scoped);
 356		rcu_read_unlock();
 357
 358		if (!(ipv6_can_nonlocal_bind(net, isk) || has_addr ||
 359		      addr_type == IPV6_ADDR_ANY))
 360			return -EADDRNOTAVAIL;
 361
 362		if (scoped)
 363			sk->sk_bound_dev_if = addr->sin6_scope_id;
 364#endif
 365	} else {
 366		return -EAFNOSUPPORT;
 367	}
 368	return 0;
 369}
 370
 371static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
 372{
 373	if (saddr->sa_family == AF_INET) {
 374		struct inet_sock *isk = inet_sk(sk);
 375		struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
 376		isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
 377#if IS_ENABLED(CONFIG_IPV6)
 378	} else if (saddr->sa_family == AF_INET6) {
 379		struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
 380		struct ipv6_pinfo *np = inet6_sk(sk);
 381		sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
 382#endif
 383	}
 384}
 385
 386static void ping_clear_saddr(struct sock *sk, int dif)
 387{
 388	sk->sk_bound_dev_if = dif;
 389	if (sk->sk_family == AF_INET) {
 390		struct inet_sock *isk = inet_sk(sk);
 391		isk->inet_rcv_saddr = isk->inet_saddr = 0;
 392#if IS_ENABLED(CONFIG_IPV6)
 393	} else if (sk->sk_family == AF_INET6) {
 394		struct ipv6_pinfo *np = inet6_sk(sk);
 395		memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
 396		memset(&np->saddr, 0, sizeof(np->saddr));
 397#endif
 398	}
 399}
 400/*
 401 * We need our own bind because there are no privileged id's == local ports.
 402 * Moreover, we don't allow binding to multi- and broadcast addresses.
 403 */
 404
 405int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 406{
 407	struct inet_sock *isk = inet_sk(sk);
 408	unsigned short snum;
 409	int err;
 410	int dif = sk->sk_bound_dev_if;
 411
 412	err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
 413	if (err)
 414		return err;
 415
 416	lock_sock(sk);
 417
 418	err = -EINVAL;
 419	if (isk->inet_num != 0)
 420		goto out;
 421
 422	err = -EADDRINUSE;
 423	ping_set_saddr(sk, uaddr);
 424	snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
 425	if (ping_get_port(sk, snum) != 0) {
 426		ping_clear_saddr(sk, dif);
 427		goto out;
 428	}
 429
 430	pr_debug("after bind(): num = %hu, dif = %d\n",
 431		 isk->inet_num,
 432		 sk->sk_bound_dev_if);
 433
 434	err = 0;
 435	if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
 436		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 437#if IS_ENABLED(CONFIG_IPV6)
 438	if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 439		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 440#endif
 441
 442	if (snum)
 443		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 444	isk->inet_sport = htons(isk->inet_num);
 445	isk->inet_daddr = 0;
 446	isk->inet_dport = 0;
 447
 448#if IS_ENABLED(CONFIG_IPV6)
 449	if (sk->sk_family == AF_INET6)
 450		memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
 451#endif
 452
 453	sk_dst_reset(sk);
 454out:
 455	release_sock(sk);
 456	pr_debug("ping_v4_bind -> %d\n", err);
 457	return err;
 458}
 459EXPORT_SYMBOL_GPL(ping_bind);
 460
 461/*
 462 * Is this a supported type of ICMP message?
 463 */
 464
 465static inline int ping_supported(int family, int type, int code)
 466{
 467	return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
 468	       (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
 469}
 470
 471/*
 472 * This routine is called by the ICMP module when it gets some
 473 * sort of error condition.
 474 */
 475
 476void ping_err(struct sk_buff *skb, int offset, u32 info)
 477{
 478	int family;
 479	struct icmphdr *icmph;
 480	struct inet_sock *inet_sock;
 481	int type;
 482	int code;
 483	struct net *net = dev_net(skb->dev);
 484	struct sock *sk;
 485	int harderr;
 486	int err;
 487
 488	if (skb->protocol == htons(ETH_P_IP)) {
 489		family = AF_INET;
 490		type = icmp_hdr(skb)->type;
 491		code = icmp_hdr(skb)->code;
 492		icmph = (struct icmphdr *)(skb->data + offset);
 493	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 494		family = AF_INET6;
 495		type = icmp6_hdr(skb)->icmp6_type;
 496		code = icmp6_hdr(skb)->icmp6_code;
 497		icmph = (struct icmphdr *) (skb->data + offset);
 498	} else {
 499		BUG();
 500	}
 501
 502	/* We assume the packet has already been checked by icmp_unreach */
 503
 504	if (!ping_supported(family, icmph->type, icmph->code))
 505		return;
 506
 507	pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
 508		 skb->protocol, type, code, ntohs(icmph->un.echo.id),
 509		 ntohs(icmph->un.echo.sequence));
 510
 511	sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 512	if (!sk) {
 513		pr_debug("no socket, dropping\n");
 514		return;	/* No socket for error */
 515	}
 516	pr_debug("err on socket %p\n", sk);
 517
 518	err = 0;
 519	harderr = 0;
 520	inet_sock = inet_sk(sk);
 521
 522	if (skb->protocol == htons(ETH_P_IP)) {
 523		switch (type) {
 524		default:
 525		case ICMP_TIME_EXCEEDED:
 526			err = EHOSTUNREACH;
 527			break;
 528		case ICMP_SOURCE_QUENCH:
 529			/* This is not a real error but ping wants to see it.
 530			 * Report it with some fake errno.
 531			 */
 532			err = EREMOTEIO;
 533			break;
 534		case ICMP_PARAMETERPROB:
 535			err = EPROTO;
 536			harderr = 1;
 537			break;
 538		case ICMP_DEST_UNREACH:
 539			if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
 540				ipv4_sk_update_pmtu(skb, sk, info);
 541				if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
 542					err = EMSGSIZE;
 543					harderr = 1;
 544					break;
 545				}
 546				goto out;
 547			}
 548			err = EHOSTUNREACH;
 549			if (code <= NR_ICMP_UNREACH) {
 550				harderr = icmp_err_convert[code].fatal;
 551				err = icmp_err_convert[code].errno;
 552			}
 553			break;
 554		case ICMP_REDIRECT:
 555			/* See ICMP_SOURCE_QUENCH */
 556			ipv4_sk_redirect(skb, sk);
 557			err = EREMOTEIO;
 558			break;
 559		}
 560#if IS_ENABLED(CONFIG_IPV6)
 561	} else if (skb->protocol == htons(ETH_P_IPV6)) {
 562		harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
 563#endif
 564	}
 565
 566	/*
 567	 *      RFC1122: OK.  Passes ICMP errors back to application, as per
 568	 *	4.1.3.3.
 569	 */
 570	if ((family == AF_INET && !inet_sock->recverr) ||
 571	    (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
 572		if (!harderr || sk->sk_state != TCP_ESTABLISHED)
 573			goto out;
 574	} else {
 575		if (family == AF_INET) {
 576			ip_icmp_error(sk, skb, err, 0 /* no remote port */,
 577				      info, (u8 *)icmph);
 578#if IS_ENABLED(CONFIG_IPV6)
 579		} else if (family == AF_INET6) {
 580			pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
 581						   info, (u8 *)icmph);
 582#endif
 583		}
 584	}
 585	sk->sk_err = err;
 586	sk->sk_error_report(sk);
 587out:
 588	sock_put(sk);
 589}
 590EXPORT_SYMBOL_GPL(ping_err);
 591
 592/*
 593 *	Copy and checksum an ICMP Echo packet from user space into a buffer
 594 *	starting from the payload.
 595 */
 596
 597int ping_getfrag(void *from, char *to,
 598		 int offset, int fraglen, int odd, struct sk_buff *skb)
 599{
 600	struct pingfakehdr *pfh = (struct pingfakehdr *)from;
 601
 602	if (offset == 0) {
 603		fraglen -= sizeof(struct icmphdr);
 604		if (fraglen < 0)
 605			BUG();
 606		if (!csum_and_copy_from_iter_full(to + sizeof(struct icmphdr),
 607			    fraglen, &pfh->wcheck,
 608			    &pfh->msg->msg_iter))
 609			return -EFAULT;
 610	} else if (offset < sizeof(struct icmphdr)) {
 611			BUG();
 612	} else {
 613		if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
 614					    &pfh->msg->msg_iter))
 
 615			return -EFAULT;
 616	}
 617
 618#if IS_ENABLED(CONFIG_IPV6)
 619	/* For IPv6, checksum each skb as we go along, as expected by
 620	 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
 621	 * wcheck, it will be finalized in ping_v4_push_pending_frames.
 622	 */
 623	if (pfh->family == AF_INET6) {
 624		skb->csum = pfh->wcheck;
 625		skb->ip_summed = CHECKSUM_NONE;
 626		pfh->wcheck = 0;
 627	}
 628#endif
 629
 630	return 0;
 631}
 632EXPORT_SYMBOL_GPL(ping_getfrag);
 633
 634static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
 635				       struct flowi4 *fl4)
 636{
 637	struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
 638
 639	if (!skb)
 640		return 0;
 641	pfh->wcheck = csum_partial((char *)&pfh->icmph,
 642		sizeof(struct icmphdr), pfh->wcheck);
 643	pfh->icmph.checksum = csum_fold(pfh->wcheck);
 644	memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
 645	skb->ip_summed = CHECKSUM_NONE;
 646	return ip_push_pending_frames(sk, fl4);
 647}
 648
 649int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
 650			void *user_icmph, size_t icmph_len) {
 651	u8 type, code;
 652
 653	if (len > 0xFFFF)
 654		return -EMSGSIZE;
 655
 656	/* Must have at least a full ICMP header. */
 657	if (len < icmph_len)
 658		return -EINVAL;
 659
 660	/*
 661	 *	Check the flags.
 662	 */
 663
 664	/* Mirror BSD error message compatibility */
 665	if (msg->msg_flags & MSG_OOB)
 666		return -EOPNOTSUPP;
 667
 668	/*
 669	 *	Fetch the ICMP header provided by the userland.
 670	 *	iovec is modified! The ICMP header is consumed.
 671	 */
 672	if (memcpy_from_msg(user_icmph, msg, icmph_len))
 673		return -EFAULT;
 674
 675	if (family == AF_INET) {
 676		type = ((struct icmphdr *) user_icmph)->type;
 677		code = ((struct icmphdr *) user_icmph)->code;
 678#if IS_ENABLED(CONFIG_IPV6)
 679	} else if (family == AF_INET6) {
 680		type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
 681		code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
 682#endif
 683	} else {
 684		BUG();
 685	}
 686
 687	if (!ping_supported(family, type, code))
 688		return -EINVAL;
 689
 690	return 0;
 691}
 692EXPORT_SYMBOL_GPL(ping_common_sendmsg);
 693
 694static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
 695{
 696	struct net *net = sock_net(sk);
 697	struct flowi4 fl4;
 698	struct inet_sock *inet = inet_sk(sk);
 699	struct ipcm_cookie ipc;
 700	struct icmphdr user_icmph;
 701	struct pingfakehdr pfh;
 702	struct rtable *rt = NULL;
 703	struct ip_options_data opt_copy;
 704	int free = 0;
 705	__be32 saddr, daddr, faddr;
 706	u8  tos;
 707	int err;
 708
 709	pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
 710
 711	err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
 712				  sizeof(user_icmph));
 713	if (err)
 714		return err;
 715
 716	/*
 717	 *	Get and verify the address.
 718	 */
 719
 720	if (msg->msg_name) {
 721		DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
 722		if (msg->msg_namelen < sizeof(*usin))
 723			return -EINVAL;
 724		if (usin->sin_family != AF_INET)
 725			return -EAFNOSUPPORT;
 726		daddr = usin->sin_addr.s_addr;
 727		/* no remote port */
 728	} else {
 729		if (sk->sk_state != TCP_ESTABLISHED)
 730			return -EDESTADDRREQ;
 731		daddr = inet->inet_daddr;
 732		/* no remote port */
 733	}
 734
 735	ipcm_init_sk(&ipc, inet);
 
 
 
 
 
 
 
 736
 737	if (msg->msg_controllen) {
 738		err = ip_cmsg_send(sk, msg, &ipc, false);
 739		if (unlikely(err)) {
 740			kfree(ipc.opt);
 741			return err;
 742		}
 743		if (ipc.opt)
 744			free = 1;
 745	}
 746	if (!ipc.opt) {
 747		struct ip_options_rcu *inet_opt;
 748
 749		rcu_read_lock();
 750		inet_opt = rcu_dereference(inet->inet_opt);
 751		if (inet_opt) {
 752			memcpy(&opt_copy, inet_opt,
 753			       sizeof(*inet_opt) + inet_opt->opt.optlen);
 754			ipc.opt = &opt_copy.opt;
 755		}
 756		rcu_read_unlock();
 757	}
 758
 759	saddr = ipc.addr;
 760	ipc.addr = faddr = daddr;
 761
 762	if (ipc.opt && ipc.opt->opt.srr) {
 763		if (!daddr) {
 764			err = -EINVAL;
 765			goto out_free;
 766		}
 767		faddr = ipc.opt->opt.faddr;
 768	}
 769	tos = get_rttos(&ipc, inet);
 770	if (sock_flag(sk, SOCK_LOCALROUTE) ||
 771	    (msg->msg_flags & MSG_DONTROUTE) ||
 772	    (ipc.opt && ipc.opt->opt.is_strictroute)) {
 773		tos |= RTO_ONLINK;
 774	}
 775
 776	if (ipv4_is_multicast(daddr)) {
 777		if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif))
 778			ipc.oif = inet->mc_index;
 779		if (!saddr)
 780			saddr = inet->mc_addr;
 781	} else if (!ipc.oif)
 782		ipc.oif = inet->uc_index;
 783
 784	flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos,
 785			   RT_SCOPE_UNIVERSE, sk->sk_protocol,
 786			   inet_sk_flowi_flags(sk), faddr, saddr, 0, 0,
 787			   sk->sk_uid);
 788
 789	fl4.fl4_icmp_type = user_icmph.type;
 790	fl4.fl4_icmp_code = user_icmph.code;
 791
 792	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
 793	rt = ip_route_output_flow(net, &fl4, sk);
 794	if (IS_ERR(rt)) {
 795		err = PTR_ERR(rt);
 796		rt = NULL;
 797		if (err == -ENETUNREACH)
 798			IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
 799		goto out;
 800	}
 801
 802	err = -EACCES;
 803	if ((rt->rt_flags & RTCF_BROADCAST) &&
 804	    !sock_flag(sk, SOCK_BROADCAST))
 805		goto out;
 806
 807	if (msg->msg_flags & MSG_CONFIRM)
 808		goto do_confirm;
 809back_from_confirm:
 810
 811	if (!ipc.addr)
 812		ipc.addr = fl4.daddr;
 813
 814	lock_sock(sk);
 815
 816	pfh.icmph.type = user_icmph.type; /* already checked */
 817	pfh.icmph.code = user_icmph.code; /* ditto */
 818	pfh.icmph.checksum = 0;
 819	pfh.icmph.un.echo.id = inet->inet_sport;
 820	pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
 821	pfh.msg = msg;
 822	pfh.wcheck = 0;
 823	pfh.family = AF_INET;
 824
 825	err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
 826			0, &ipc, &rt, msg->msg_flags);
 827	if (err)
 828		ip_flush_pending_frames(sk);
 829	else
 830		err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
 831	release_sock(sk);
 832
 833out:
 834	ip_rt_put(rt);
 835out_free:
 836	if (free)
 837		kfree(ipc.opt);
 838	if (!err) {
 839		icmp_out_count(sock_net(sk), user_icmph.type);
 840		return len;
 841	}
 842	return err;
 843
 844do_confirm:
 845	if (msg->msg_flags & MSG_PROBE)
 846		dst_confirm_neigh(&rt->dst, &fl4.daddr);
 847	if (!(msg->msg_flags & MSG_PROBE) || len)
 848		goto back_from_confirm;
 849	err = 0;
 850	goto out;
 851}
 852
 853int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
 854		 int flags, int *addr_len)
 855{
 856	struct inet_sock *isk = inet_sk(sk);
 857	int family = sk->sk_family;
 858	struct sk_buff *skb;
 859	int copied, err;
 860
 861	pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
 862
 863	err = -EOPNOTSUPP;
 864	if (flags & MSG_OOB)
 865		goto out;
 866
 867	if (flags & MSG_ERRQUEUE)
 868		return inet_recv_error(sk, msg, len, addr_len);
 
 
 
 
 
 
 
 
 869
 870	skb = skb_recv_datagram(sk, flags, noblock, &err);
 871	if (!skb)
 872		goto out;
 873
 874	copied = skb->len;
 875	if (copied > len) {
 876		msg->msg_flags |= MSG_TRUNC;
 877		copied = len;
 878	}
 879
 880	/* Don't bother checking the checksum */
 881	err = skb_copy_datagram_msg(skb, 0, msg, copied);
 882	if (err)
 883		goto done;
 884
 885	sock_recv_timestamp(msg, sk, skb);
 886
 887	/* Copy the address and add cmsg data. */
 888	if (family == AF_INET) {
 889		DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
 890
 891		if (sin) {
 892			sin->sin_family = AF_INET;
 893			sin->sin_port = 0 /* skb->h.uh->source */;
 894			sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 895			memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 896			*addr_len = sizeof(*sin);
 897		}
 898
 899		if (isk->cmsg_flags)
 900			ip_cmsg_recv(msg, skb);
 901
 902#if IS_ENABLED(CONFIG_IPV6)
 903	} else if (family == AF_INET6) {
 904		struct ipv6_pinfo *np = inet6_sk(sk);
 905		struct ipv6hdr *ip6 = ipv6_hdr(skb);
 906		DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
 907
 908		if (sin6) {
 909			sin6->sin6_family = AF_INET6;
 910			sin6->sin6_port = 0;
 911			sin6->sin6_addr = ip6->saddr;
 912			sin6->sin6_flowinfo = 0;
 913			if (np->sndflow)
 914				sin6->sin6_flowinfo = ip6_flowinfo(ip6);
 915			sin6->sin6_scope_id =
 916				ipv6_iface_scope_id(&sin6->sin6_addr,
 917						    inet6_iif(skb));
 918			*addr_len = sizeof(*sin6);
 919		}
 920
 921		if (inet6_sk(sk)->rxopt.all)
 922			pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
 923		if (skb->protocol == htons(ETH_P_IPV6) &&
 924		    inet6_sk(sk)->rxopt.all)
 925			pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
 926		else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
 927			ip_cmsg_recv(msg, skb);
 928#endif
 929	} else {
 930		BUG();
 931	}
 932
 933	err = copied;
 934
 935done:
 936	skb_free_datagram(sk, skb);
 937out:
 938	pr_debug("ping_recvmsg -> %d\n", err);
 939	return err;
 940}
 941EXPORT_SYMBOL_GPL(ping_recvmsg);
 942
 943int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 944{
 945	pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
 946		 inet_sk(sk), inet_sk(sk)->inet_num, skb);
 947	if (sock_queue_rcv_skb(sk, skb) < 0) {
 948		kfree_skb(skb);
 949		pr_debug("ping_queue_rcv_skb -> failed\n");
 950		return -1;
 951	}
 952	return 0;
 953}
 954EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
 955
 956
 957/*
 958 *	All we need to do is get the socket.
 959 */
 960
 961bool ping_rcv(struct sk_buff *skb)
 962{
 963	struct sock *sk;
 964	struct net *net = dev_net(skb->dev);
 965	struct icmphdr *icmph = icmp_hdr(skb);
 966
 967	/* We assume the packet has already been checked by icmp_rcv */
 968
 969	pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
 970		 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
 971
 972	/* Push ICMP header back */
 973	skb_push(skb, skb->data - (u8 *)icmph);
 974
 975	sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
 976	if (sk) {
 977		struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 978
 979		pr_debug("rcv on socket %p\n", sk);
 980		if (skb2)
 981			ping_queue_rcv_skb(sk, skb2);
 982		sock_put(sk);
 983		return true;
 984	}
 985	pr_debug("no socket, dropping\n");
 986
 987	return false;
 988}
 989EXPORT_SYMBOL_GPL(ping_rcv);
 990
 991struct proto ping_prot = {
 992	.name =		"PING",
 993	.owner =	THIS_MODULE,
 994	.init =		ping_init_sock,
 995	.close =	ping_close,
 996	.connect =	ip4_datagram_connect,
 997	.disconnect =	__udp_disconnect,
 998	.setsockopt =	ip_setsockopt,
 999	.getsockopt =	ip_getsockopt,
1000	.sendmsg =	ping_v4_sendmsg,
1001	.recvmsg =	ping_recvmsg,
1002	.bind =		ping_bind,
1003	.backlog_rcv =	ping_queue_rcv_skb,
1004	.release_cb =	ip4_datagram_release_cb,
1005	.hash =		ping_hash,
1006	.unhash =	ping_unhash,
1007	.get_port =	ping_get_port,
1008	.obj_size =	sizeof(struct inet_sock),
1009};
1010EXPORT_SYMBOL(ping_prot);
1011
1012#ifdef CONFIG_PROC_FS
1013
1014static struct sock *ping_get_first(struct seq_file *seq, int start)
1015{
1016	struct sock *sk;
1017	struct ping_iter_state *state = seq->private;
1018	struct net *net = seq_file_net(seq);
1019
1020	for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1021	     ++state->bucket) {
1022		struct hlist_nulls_node *node;
1023		struct hlist_nulls_head *hslot;
1024
1025		hslot = &ping_table.hash[state->bucket];
1026
1027		if (hlist_nulls_empty(hslot))
1028			continue;
1029
1030		sk_nulls_for_each(sk, node, hslot) {
1031			if (net_eq(sock_net(sk), net) &&
1032			    sk->sk_family == state->family)
1033				goto found;
1034		}
1035	}
1036	sk = NULL;
1037found:
1038	return sk;
1039}
1040
1041static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1042{
1043	struct ping_iter_state *state = seq->private;
1044	struct net *net = seq_file_net(seq);
1045
1046	do {
1047		sk = sk_nulls_next(sk);
1048	} while (sk && (!net_eq(sock_net(sk), net)));
1049
1050	if (!sk)
1051		return ping_get_first(seq, state->bucket + 1);
1052	return sk;
1053}
1054
1055static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1056{
1057	struct sock *sk = ping_get_first(seq, 0);
1058
1059	if (sk)
1060		while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1061			--pos;
1062	return pos ? NULL : sk;
1063}
1064
1065void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1066	__acquires(ping_table.lock)
1067{
1068	struct ping_iter_state *state = seq->private;
1069	state->bucket = 0;
1070	state->family = family;
1071
1072	read_lock_bh(&ping_table.lock);
1073
1074	return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1075}
1076EXPORT_SYMBOL_GPL(ping_seq_start);
1077
1078static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1079{
1080	return ping_seq_start(seq, pos, AF_INET);
1081}
1082
1083void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1084{
1085	struct sock *sk;
1086
1087	if (v == SEQ_START_TOKEN)
1088		sk = ping_get_idx(seq, 0);
1089	else
1090		sk = ping_get_next(seq, v);
1091
1092	++*pos;
1093	return sk;
1094}
1095EXPORT_SYMBOL_GPL(ping_seq_next);
1096
1097void ping_seq_stop(struct seq_file *seq, void *v)
1098	__releases(ping_table.lock)
1099{
1100	read_unlock_bh(&ping_table.lock);
1101}
1102EXPORT_SYMBOL_GPL(ping_seq_stop);
1103
1104static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1105		int bucket)
1106{
1107	struct inet_sock *inet = inet_sk(sp);
1108	__be32 dest = inet->inet_daddr;
1109	__be32 src = inet->inet_rcv_saddr;
1110	__u16 destp = ntohs(inet->inet_dport);
1111	__u16 srcp = ntohs(inet->inet_sport);
1112
1113	seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1114		" %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u",
1115		bucket, src, srcp, dest, destp, sp->sk_state,
1116		sk_wmem_alloc_get(sp),
1117		sk_rmem_alloc_get(sp),
1118		0, 0L, 0,
1119		from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1120		0, sock_i_ino(sp),
1121		refcount_read(&sp->sk_refcnt), sp,
1122		atomic_read(&sp->sk_drops));
1123}
1124
1125static int ping_v4_seq_show(struct seq_file *seq, void *v)
1126{
1127	seq_setwidth(seq, 127);
1128	if (v == SEQ_START_TOKEN)
1129		seq_puts(seq, "  sl  local_address rem_address   st tx_queue "
1130			   "rx_queue tr tm->when retrnsmt   uid  timeout "
1131			   "inode ref pointer drops");
1132	else {
1133		struct ping_iter_state *state = seq->private;
1134
1135		ping_v4_format_sock(v, seq, state->bucket);
1136	}
1137	seq_pad(seq, '\n');
1138	return 0;
1139}
1140
1141static const struct seq_operations ping_v4_seq_ops = {
 
1142	.start		= ping_v4_seq_start,
1143	.show		= ping_v4_seq_show,
1144	.next		= ping_seq_next,
1145	.stop		= ping_seq_stop,
1146};
1147
1148static int __net_init ping_v4_proc_init_net(struct net *net)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1149{
1150	if (!proc_create_net("icmp", 0444, net->proc_net, &ping_v4_seq_ops,
1151			sizeof(struct ping_iter_state)))
 
 
1152		return -ENOMEM;
1153	return 0;
1154}
 
 
 
 
 
 
 
 
 
 
 
 
1155
1156static void __net_exit ping_v4_proc_exit_net(struct net *net)
1157{
1158	remove_proc_entry("icmp", net->proc_net);
1159}
1160
1161static struct pernet_operations ping_v4_net_ops = {
1162	.init = ping_v4_proc_init_net,
1163	.exit = ping_v4_proc_exit_net,
1164};
1165
1166int __init ping_proc_init(void)
1167{
1168	return register_pernet_subsys(&ping_v4_net_ops);
1169}
1170
1171void ping_proc_exit(void)
1172{
1173	unregister_pernet_subsys(&ping_v4_net_ops);
1174}
1175
1176#endif
1177
1178void __init ping_init(void)
1179{
1180	int i;
1181
1182	for (i = 0; i < PING_HTABLE_SIZE; i++)
1183		INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1184	rwlock_init(&ping_table.lock);
1185}