1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
4 * user-supplied information to configure own IP address and routes.
5 *
6 * Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
7 *
8 * Derived from network configuration code in fs/nfs/nfsroot.c,
9 * originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
10 *
11 * BOOTP rewritten to construct and analyse packets itself instead
12 * of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
13 * -- MJ, December 1998
14 *
15 * Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
16 * initialization scheme.
17 * - Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
18 *
19 * DHCP support added. To users this looks like a whole separate
20 * protocol, but we know it's just a bag on the side of BOOTP.
21 * -- Chip Salzenberg <chip@valinux.com>, May 2000
22 *
23 * Ported DHCP support from 2.2.16 to 2.4.0-test4
24 * -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
25 *
26 * Merged changes from 2.2.19 into 2.4.3
27 * -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
28 *
29 * Multiple Nameservers in /proc/net/pnp
30 * -- Josef Siemes <jsiemes@web.de>, Aug 2002
31 *
32 * NTP servers in /proc/net/ipconfig/ntp_servers
33 * -- Chris Novakovic <chris@chrisn.me.uk>, April 2018
34 */
35
36 #include <linux/types.h>
37 #include <linux/string.h>
38 #include <linux/kernel.h>
39 #include <linux/jiffies.h>
40 #include <linux/random.h>
41 #include <linux/init.h>
42 #include <linux/utsname.h>
43 #include <linux/in.h>
44 #include <linux/if.h>
45 #include <linux/inet.h>
46 #include <linux/inetdevice.h>
47 #include <linux/netdevice.h>
48 #include <linux/if_arp.h>
49 #include <linux/skbuff.h>
50 #include <linux/ip.h>
51 #include <linux/socket.h>
52 #include <linux/route.h>
53 #include <linux/udp.h>
54 #include <linux/proc_fs.h>
55 #include <linux/seq_file.h>
56 #include <linux/major.h>
57 #include <linux/root_dev.h>
58 #include <linux/delay.h>
59 #include <linux/nfs_fs.h>
60 #include <linux/slab.h>
61 #include <linux/export.h>
62 #include <net/net_namespace.h>
63 #include <net/arp.h>
64 #include <net/ip.h>
65 #include <net/ipconfig.h>
66 #include <net/route.h>
67
68 #include <linux/uaccess.h>
69 #include <net/checksum.h>
70 #include <asm/processor.h>
71
72 #if defined(CONFIG_IP_PNP_DHCP)
73 #define IPCONFIG_DHCP
74 #endif
75 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
76 #define IPCONFIG_BOOTP
77 #endif
78 #if defined(CONFIG_IP_PNP_RARP)
79 #define IPCONFIG_RARP
80 #endif
81 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
82 #define IPCONFIG_DYNAMIC
83 #endif
84
85 /* Define the friendly delay before and after opening net devices */
86 #define CONF_POST_OPEN 10 /* After opening: 10 msecs */
87
88 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
89 #define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */
90 #define CONF_SEND_RETRIES 6 /* Send six requests per open */
91 #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
92 #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
93 #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
94 #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
95 #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
96 - '3' from resolv.h */
97 #define CONF_NTP_SERVERS_MAX 3 /* Maximum number of NTP servers */
98
99 #define NONE cpu_to_be32(INADDR_NONE)
100 #define ANY cpu_to_be32(INADDR_ANY)
101
102 /* Wait for carrier timeout default in seconds */
103 static unsigned int carrier_timeout = 120;
104
105 /*
106 * Public IP configuration
107 */
108
109 /* This is used by platforms which might be able to set the ipconfig
110 * variables using firmware environment vars. If this is set, it will
111 * ignore such firmware variables.
112 */
113 int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
114
115 static int ic_enable __initdata; /* IP config enabled? */
116
117 /* Protocol choice */
118 int ic_proto_enabled __initdata = 0
119 #ifdef IPCONFIG_BOOTP
120 | IC_BOOTP
121 #endif
122 #ifdef CONFIG_IP_PNP_DHCP
123 | IC_USE_DHCP
124 #endif
125 #ifdef IPCONFIG_RARP
126 | IC_RARP
127 #endif
128 ;
129
130 static int ic_host_name_set __initdata; /* Host name set by us? */
131
132 __be32 ic_myaddr = NONE; /* My IP address */
133 static __be32 ic_netmask = NONE; /* Netmask for local subnet */
134 __be32 ic_gateway = NONE; /* Gateway IP address */
135
136 #ifdef IPCONFIG_DYNAMIC
137 static __be32 ic_addrservaddr = NONE; /* IP Address of the IP addresses'server */
138 #endif
139
140 __be32 ic_servaddr = NONE; /* Boot server IP address */
141
142 __be32 root_server_addr = NONE; /* Address of NFS server */
143 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
144
145 /* vendor class identifier */
146 static char vendor_class_identifier[253] __initdata;
147
148 #if defined(CONFIG_IP_PNP_DHCP)
149 static char dhcp_client_identifier[253] __initdata;
150 #endif
151
152 /* Persistent data: */
153
154 #ifdef IPCONFIG_DYNAMIC
155 static int ic_proto_used; /* Protocol used, if any */
156 #else
157 #define ic_proto_used 0
158 #endif
159 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
160 static __be32 ic_ntp_servers[CONF_NTP_SERVERS_MAX]; /* NTP server IP addresses */
161 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
162
163 /*
164 * Private state.
165 */
166
167 /* Name of user-selected boot device */
168 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
169
170 /* Protocols supported by available interfaces */
171 static int ic_proto_have_if __initdata;
172
173 /* MTU for boot device */
174 static int ic_dev_mtu __initdata;
175
176 #ifdef IPCONFIG_DYNAMIC
177 static DEFINE_SPINLOCK(ic_recv_lock);
178 static volatile int ic_got_reply __initdata; /* Proto(s) that replied */
179 #endif
180 #ifdef IPCONFIG_DHCP
181 static int ic_dhcp_msgtype __initdata; /* DHCP msg type received */
182 #endif
183
184
185 /*
186 * Network devices
187 */
188
189 struct ic_device {
190 struct ic_device *next;
191 struct net_device *dev;
192 unsigned short flags;
193 short able;
194 __be32 xid;
195 };
196
197 static struct ic_device *ic_first_dev __initdata; /* List of open device */
198 static struct ic_device *ic_dev __initdata; /* Selected device */
199
ic_is_init_dev(struct net_device * dev)200 static bool __init ic_is_init_dev(struct net_device *dev)
201 {
202 if (dev->flags & IFF_LOOPBACK)
203 return false;
204 return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
205 (!(dev->flags & IFF_LOOPBACK) &&
206 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
207 strncmp(dev->name, "dummy", 5));
208 }
209
ic_open_devs(void)210 static int __init ic_open_devs(void)
211 {
212 struct ic_device *d, **last;
213 struct net_device *dev;
214 unsigned short oflags;
215 unsigned long start, next_msg;
216
217 last = &ic_first_dev;
218 rtnl_lock();
219
220 /* bring loopback device up first */
221 for_each_netdev(&init_net, dev) {
222 if (!(dev->flags & IFF_LOOPBACK))
223 continue;
224 if (dev_change_flags(dev, dev->flags | IFF_UP, NULL) < 0)
225 pr_err("IP-Config: Failed to open %s\n", dev->name);
226 }
227
228 for_each_netdev(&init_net, dev) {
229 if (ic_is_init_dev(dev)) {
230 int able = 0;
231 if (dev->mtu >= 364)
232 able |= IC_BOOTP;
233 else
234 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
235 dev->name, dev->mtu);
236 if (!(dev->flags & IFF_NOARP))
237 able |= IC_RARP;
238 able &= ic_proto_enabled;
239 if (ic_proto_enabled && !able)
240 continue;
241 oflags = dev->flags;
242 if (dev_change_flags(dev, oflags | IFF_UP, NULL) < 0) {
243 pr_err("IP-Config: Failed to open %s\n",
244 dev->name);
245 continue;
246 }
247 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
248 rtnl_unlock();
249 return -ENOMEM;
250 }
251 d->dev = dev;
252 *last = d;
253 last = &d->next;
254 d->flags = oflags;
255 d->able = able;
256 if (able & IC_BOOTP)
257 get_random_bytes(&d->xid, sizeof(__be32));
258 else
259 d->xid = 0;
260 ic_proto_have_if |= able;
261 pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
262 dev->name, able, d->xid);
263 }
264 }
265 /* Devices with a complex topology like SFP ethernet interfaces needs
266 * the rtnl_lock at init. The carrier wait-loop must therefore run
267 * without holding it.
268 */
269 rtnl_unlock();
270
271 /* no point in waiting if we could not bring up at least one device */
272 if (!ic_first_dev)
273 goto have_carrier;
274
275 /* wait for a carrier on at least one device */
276 start = jiffies;
277 next_msg = start + msecs_to_jiffies(20000);
278 while (time_before(jiffies, start +
279 msecs_to_jiffies(carrier_timeout * 1000))) {
280 int wait, elapsed;
281
282 rtnl_lock();
283 for_each_netdev(&init_net, dev)
284 if (ic_is_init_dev(dev) && netif_carrier_ok(dev)) {
285 rtnl_unlock();
286 goto have_carrier;
287 }
288 rtnl_unlock();
289
290 msleep(1);
291
292 if (time_before(jiffies, next_msg))
293 continue;
294
295 elapsed = jiffies_to_msecs(jiffies - start);
296 wait = (carrier_timeout * 1000 - elapsed + 500) / 1000;
297 pr_info("Waiting up to %d more seconds for network.\n", wait);
298 next_msg = jiffies + msecs_to_jiffies(20000);
299 }
300 have_carrier:
301
302 *last = NULL;
303
304 if (!ic_first_dev) {
305 if (user_dev_name[0])
306 pr_err("IP-Config: Device `%s' not found\n",
307 user_dev_name);
308 else
309 pr_err("IP-Config: No network devices available\n");
310 return -ENODEV;
311 }
312 return 0;
313 }
314
315 /* Close all network interfaces except the one we've autoconfigured, and its
316 * lowers, in case it's a stacked virtual interface.
317 */
ic_close_devs(void)318 static void __init ic_close_devs(void)
319 {
320 struct net_device *selected_dev = ic_dev ? ic_dev->dev : NULL;
321 struct ic_device *d, *next;
322 struct net_device *dev;
323
324 rtnl_lock();
325 next = ic_first_dev;
326 while ((d = next)) {
327 bool bring_down = (d != ic_dev);
328 struct net_device *lower;
329 struct list_head *iter;
330
331 next = d->next;
332 dev = d->dev;
333
334 if (selected_dev) {
335 netdev_for_each_lower_dev(selected_dev, lower, iter) {
336 if (dev == lower) {
337 bring_down = false;
338 break;
339 }
340 }
341 }
342 if (bring_down) {
343 pr_debug("IP-Config: Downing %s\n", dev->name);
344 dev_change_flags(dev, d->flags, NULL);
345 }
346 kfree(d);
347 }
348 rtnl_unlock();
349 }
350
351 /*
352 * Interface to various network functions.
353 */
354
355 static inline void
set_sockaddr(struct sockaddr_in * sin,__be32 addr,__be16 port)356 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
357 {
358 sin->sin_family = AF_INET;
359 sin->sin_addr.s_addr = addr;
360 sin->sin_port = port;
361 }
362
363 /*
364 * Set up interface addresses and routes.
365 */
366
ic_setup_if(void)367 static int __init ic_setup_if(void)
368 {
369 struct ifreq ir;
370 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
371 int err;
372
373 memset(&ir, 0, sizeof(ir));
374 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
375 set_sockaddr(sin, ic_myaddr, 0);
376 if ((err = devinet_ioctl(&init_net, SIOCSIFADDR, &ir)) < 0) {
377 pr_err("IP-Config: Unable to set interface address (%d)\n",
378 err);
379 return -1;
380 }
381 set_sockaddr(sin, ic_netmask, 0);
382 if ((err = devinet_ioctl(&init_net, SIOCSIFNETMASK, &ir)) < 0) {
383 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
384 err);
385 return -1;
386 }
387 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
388 if ((err = devinet_ioctl(&init_net, SIOCSIFBRDADDR, &ir)) < 0) {
389 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
390 err);
391 return -1;
392 }
393 /* Handle the case where we need non-standard MTU on the boot link (a network
394 * using jumbo frames, for instance). If we can't set the mtu, don't error
395 * out, we'll try to muddle along.
396 */
397 if (ic_dev_mtu != 0) {
398 rtnl_lock();
399 if ((err = dev_set_mtu(ic_dev->dev, ic_dev_mtu)) < 0)
400 pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
401 ic_dev_mtu, err);
402 rtnl_unlock();
403 }
404 return 0;
405 }
406
ic_setup_routes(void)407 static int __init ic_setup_routes(void)
408 {
409 /* No need to setup device routes, only the default route... */
410
411 if (ic_gateway != NONE) {
412 struct rtentry rm;
413 int err;
414
415 memset(&rm, 0, sizeof(rm));
416 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
417 pr_err("IP-Config: Gateway not on directly connected network\n");
418 return -1;
419 }
420 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
421 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
422 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
423 rm.rt_flags = RTF_UP | RTF_GATEWAY;
424 if ((err = ip_rt_ioctl(&init_net, SIOCADDRT, &rm)) < 0) {
425 pr_err("IP-Config: Cannot add default route (%d)\n",
426 err);
427 return -1;
428 }
429 }
430
431 return 0;
432 }
433
434 /*
435 * Fill in default values for all missing parameters.
436 */
437
ic_defaults(void)438 static int __init ic_defaults(void)
439 {
440 /*
441 * At this point we have no userspace running so need not
442 * claim locks on system_utsname
443 */
444
445 if (!ic_host_name_set)
446 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
447
448 if (root_server_addr == NONE)
449 root_server_addr = ic_servaddr;
450
451 if (ic_netmask == NONE) {
452 if (IN_CLASSA(ntohl(ic_myaddr)))
453 ic_netmask = htonl(IN_CLASSA_NET);
454 else if (IN_CLASSB(ntohl(ic_myaddr)))
455 ic_netmask = htonl(IN_CLASSB_NET);
456 else if (IN_CLASSC(ntohl(ic_myaddr)))
457 ic_netmask = htonl(IN_CLASSC_NET);
458 else if (IN_CLASSE(ntohl(ic_myaddr)))
459 ic_netmask = htonl(IN_CLASSE_NET);
460 else {
461 pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
462 &ic_myaddr);
463 return -1;
464 }
465 pr_notice("IP-Config: Guessing netmask %pI4\n",
466 &ic_netmask);
467 }
468
469 return 0;
470 }
471
472 /*
473 * RARP support.
474 */
475
476 #ifdef IPCONFIG_RARP
477
478 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
479
480 static struct packet_type rarp_packet_type __initdata = {
481 .type = cpu_to_be16(ETH_P_RARP),
482 .func = ic_rarp_recv,
483 };
484
ic_rarp_init(void)485 static inline void __init ic_rarp_init(void)
486 {
487 dev_add_pack(&rarp_packet_type);
488 }
489
ic_rarp_cleanup(void)490 static inline void __init ic_rarp_cleanup(void)
491 {
492 dev_remove_pack(&rarp_packet_type);
493 }
494
495 /*
496 * Process received RARP packet.
497 */
498 static int __init
ic_rarp_recv(struct sk_buff * skb,struct net_device * dev,struct packet_type * pt,struct net_device * orig_dev)499 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
500 {
501 struct arphdr *rarp;
502 unsigned char *rarp_ptr;
503 __be32 sip, tip;
504 unsigned char *tha; /* t for "target" */
505 struct ic_device *d;
506
507 if (!net_eq(dev_net(dev), &init_net))
508 goto drop;
509
510 skb = skb_share_check(skb, GFP_ATOMIC);
511 if (!skb)
512 return NET_RX_DROP;
513
514 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
515 goto drop;
516
517 /* Basic sanity checks can be done without the lock. */
518 rarp = (struct arphdr *)skb_transport_header(skb);
519
520 /* If this test doesn't pass, it's not IP, or we should
521 * ignore it anyway.
522 */
523 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
524 goto drop;
525
526 /* If it's not a RARP reply, delete it. */
527 if (rarp->ar_op != htons(ARPOP_RREPLY))
528 goto drop;
529
530 /* If it's not Ethernet, delete it. */
531 if (rarp->ar_pro != htons(ETH_P_IP))
532 goto drop;
533
534 if (!pskb_may_pull(skb, arp_hdr_len(dev)))
535 goto drop;
536
537 /* OK, it is all there and looks valid, process... */
538 rarp = (struct arphdr *)skb_transport_header(skb);
539 rarp_ptr = (unsigned char *) (rarp + 1);
540
541 /* One reply at a time, please. */
542 spin_lock(&ic_recv_lock);
543
544 /* If we already have a reply, just drop the packet */
545 if (ic_got_reply)
546 goto drop_unlock;
547
548 /* Find the ic_device that the packet arrived on */
549 d = ic_first_dev;
550 while (d && d->dev != dev)
551 d = d->next;
552 if (!d)
553 goto drop_unlock; /* should never happen */
554
555 /* Extract variable-width fields */
556 rarp_ptr += dev->addr_len;
557 memcpy(&sip, rarp_ptr, 4);
558 rarp_ptr += 4;
559 tha = rarp_ptr;
560 rarp_ptr += dev->addr_len;
561 memcpy(&tip, rarp_ptr, 4);
562
563 /* Discard packets which are not meant for us. */
564 if (memcmp(tha, dev->dev_addr, dev->addr_len))
565 goto drop_unlock;
566
567 /* Discard packets which are not from specified server. */
568 if (ic_servaddr != NONE && ic_servaddr != sip)
569 goto drop_unlock;
570
571 /* We have a winner! */
572 ic_dev = d;
573 if (ic_myaddr == NONE)
574 ic_myaddr = tip;
575 ic_servaddr = sip;
576 ic_addrservaddr = sip;
577 ic_got_reply = IC_RARP;
578
579 drop_unlock:
580 /* Show's over. Nothing to see here. */
581 spin_unlock(&ic_recv_lock);
582
583 drop:
584 /* Throw the packet out. */
585 kfree_skb(skb);
586 return 0;
587 }
588
589
590 /*
591 * Send RARP request packet over a single interface.
592 */
ic_rarp_send_if(struct ic_device * d)593 static void __init ic_rarp_send_if(struct ic_device *d)
594 {
595 struct net_device *dev = d->dev;
596 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
597 dev->dev_addr, dev->dev_addr);
598 }
599 #endif
600
601 /*
602 * Predefine Nameservers
603 */
ic_nameservers_predef(void)604 static inline void __init ic_nameservers_predef(void)
605 {
606 int i;
607
608 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
609 ic_nameservers[i] = NONE;
610 }
611
612 /* Predefine NTP servers */
ic_ntp_servers_predef(void)613 static inline void __init ic_ntp_servers_predef(void)
614 {
615 int i;
616
617 for (i = 0; i < CONF_NTP_SERVERS_MAX; i++)
618 ic_ntp_servers[i] = NONE;
619 }
620
621 /*
622 * DHCP/BOOTP support.
623 */
624
625 #ifdef IPCONFIG_BOOTP
626
627 struct bootp_pkt { /* BOOTP packet format */
628 struct iphdr iph; /* IP header */
629 struct udphdr udph; /* UDP header */
630 u8 op; /* 1=request, 2=reply */
631 u8 htype; /* HW address type */
632 u8 hlen; /* HW address length */
633 u8 hops; /* Used only by gateways */
634 __be32 xid; /* Transaction ID */
635 __be16 secs; /* Seconds since we started */
636 __be16 flags; /* Just what it says */
637 __be32 client_ip; /* Client's IP address if known */
638 __be32 your_ip; /* Assigned IP address */
639 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
640 __be32 relay_ip; /* IP address of BOOTP relay */
641 u8 hw_addr[16]; /* Client's HW address */
642 u8 serv_name[64]; /* Server host name */
643 u8 boot_file[128]; /* Name of boot file */
644 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
645 };
646
647 /* packet ops */
648 #define BOOTP_REQUEST 1
649 #define BOOTP_REPLY 2
650
651 /* DHCP message types */
652 #define DHCPDISCOVER 1
653 #define DHCPOFFER 2
654 #define DHCPREQUEST 3
655 #define DHCPDECLINE 4
656 #define DHCPACK 5
657 #define DHCPNAK 6
658 #define DHCPRELEASE 7
659 #define DHCPINFORM 8
660
661 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
662
663 static struct packet_type bootp_packet_type __initdata = {
664 .type = cpu_to_be16(ETH_P_IP),
665 .func = ic_bootp_recv,
666 };
667
668 /*
669 * Initialize DHCP/BOOTP extension fields in the request.
670 */
671
672 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
673
674 #ifdef IPCONFIG_DHCP
675
676 static void __init
ic_dhcp_init_options(u8 * options,struct ic_device * d)677 ic_dhcp_init_options(u8 *options, struct ic_device *d)
678 {
679 u8 mt = ((ic_servaddr == NONE)
680 ? DHCPDISCOVER : DHCPREQUEST);
681 u8 *e = options;
682 int len;
683
684 pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
685
686 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
687 e += 4;
688
689 *e++ = 53; /* DHCP message type */
690 *e++ = 1;
691 *e++ = mt;
692
693 if (mt == DHCPREQUEST) {
694 *e++ = 54; /* Server ID (IP address) */
695 *e++ = 4;
696 memcpy(e, &ic_servaddr, 4);
697 e += 4;
698
699 *e++ = 50; /* Requested IP address */
700 *e++ = 4;
701 memcpy(e, &ic_myaddr, 4);
702 e += 4;
703 }
704
705 /* always? */
706 {
707 static const u8 ic_req_params[] = {
708 1, /* Subnet mask */
709 3, /* Default gateway */
710 6, /* DNS server */
711 12, /* Host name */
712 15, /* Domain name */
713 17, /* Boot path */
714 26, /* MTU */
715 40, /* NIS domain name */
716 42, /* NTP servers */
717 };
718
719 *e++ = 55; /* Parameter request list */
720 *e++ = sizeof(ic_req_params);
721 memcpy(e, ic_req_params, sizeof(ic_req_params));
722 e += sizeof(ic_req_params);
723
724 if (ic_host_name_set) {
725 *e++ = 12; /* host-name */
726 len = strlen(utsname()->nodename);
727 *e++ = len;
728 memcpy(e, utsname()->nodename, len);
729 e += len;
730 }
731 if (*vendor_class_identifier) {
732 pr_info("DHCP: sending class identifier \"%s\"\n",
733 vendor_class_identifier);
734 *e++ = 60; /* Class-identifier */
735 len = strlen(vendor_class_identifier);
736 *e++ = len;
737 memcpy(e, vendor_class_identifier, len);
738 e += len;
739 }
740 len = strlen(dhcp_client_identifier + 1);
741 /* the minimum length of identifier is 2, include 1 byte type,
742 * and can not be larger than the length of options
743 */
744 if (len >= 1 && len < 312 - (e - options) - 1) {
745 *e++ = 61;
746 *e++ = len + 1;
747 memcpy(e, dhcp_client_identifier, len + 1);
748 e += len + 1;
749 }
750 }
751
752 *e++ = 255; /* End of the list */
753 }
754
755 #endif /* IPCONFIG_DHCP */
756
ic_bootp_init_ext(u8 * e)757 static void __init ic_bootp_init_ext(u8 *e)
758 {
759 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
760 e += 4;
761 *e++ = 1; /* Subnet mask request */
762 *e++ = 4;
763 e += 4;
764 *e++ = 3; /* Default gateway request */
765 *e++ = 4;
766 e += 4;
767 #if CONF_NAMESERVERS_MAX > 0
768 *e++ = 6; /* (DNS) name server request */
769 *e++ = 4 * CONF_NAMESERVERS_MAX;
770 e += 4 * CONF_NAMESERVERS_MAX;
771 #endif
772 *e++ = 12; /* Host name request */
773 *e++ = 32;
774 e += 32;
775 *e++ = 40; /* NIS Domain name request */
776 *e++ = 32;
777 e += 32;
778 *e++ = 17; /* Boot path */
779 *e++ = 40;
780 e += 40;
781
782 *e++ = 57; /* set extension buffer size for reply */
783 *e++ = 2;
784 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
785 *e++ = 150;
786
787 *e++ = 255; /* End of the list */
788 }
789
790
791 /*
792 * Initialize the DHCP/BOOTP mechanism.
793 */
ic_bootp_init(void)794 static inline void __init ic_bootp_init(void)
795 {
796 /* Re-initialise all name servers and NTP servers to NONE, in case any
797 * were set via the "ip=" or "nfsaddrs=" kernel command line parameters:
798 * any IP addresses specified there will already have been decoded but
799 * are no longer needed
800 */
801 ic_nameservers_predef();
802 ic_ntp_servers_predef();
803
804 dev_add_pack(&bootp_packet_type);
805 }
806
807
808 /*
809 * DHCP/BOOTP cleanup.
810 */
ic_bootp_cleanup(void)811 static inline void __init ic_bootp_cleanup(void)
812 {
813 dev_remove_pack(&bootp_packet_type);
814 }
815
816
817 /*
818 * Send DHCP/BOOTP request to single interface.
819 */
ic_bootp_send_if(struct ic_device * d,unsigned long jiffies_diff)820 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
821 {
822 struct net_device *dev = d->dev;
823 struct sk_buff *skb;
824 struct bootp_pkt *b;
825 struct iphdr *h;
826 int hlen = LL_RESERVED_SPACE(dev);
827 int tlen = dev->needed_tailroom;
828
829 /* Allocate packet */
830 skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
831 GFP_KERNEL);
832 if (!skb)
833 return;
834 skb_reserve(skb, hlen);
835 b = skb_put_zero(skb, sizeof(struct bootp_pkt));
836
837 /* Construct IP header */
838 skb_reset_network_header(skb);
839 h = ip_hdr(skb);
840 h->version = 4;
841 h->ihl = 5;
842 h->tot_len = htons(sizeof(struct bootp_pkt));
843 h->frag_off = htons(IP_DF);
844 h->ttl = 64;
845 h->protocol = IPPROTO_UDP;
846 h->daddr = htonl(INADDR_BROADCAST);
847 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
848
849 /* Construct UDP header */
850 b->udph.source = htons(68);
851 b->udph.dest = htons(67);
852 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
853 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
854
855 /* Construct DHCP/BOOTP header */
856 b->op = BOOTP_REQUEST;
857 if (dev->type < 256) /* check for false types */
858 b->htype = dev->type;
859 else if (dev->type == ARPHRD_FDDI)
860 b->htype = ARPHRD_ETHER;
861 else {
862 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
863 dev->name);
864 b->htype = dev->type; /* can cause undefined behavior */
865 }
866
867 /* server_ip and your_ip address are both already zero per RFC2131 */
868 b->hlen = dev->addr_len;
869 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
870 b->secs = htons(jiffies_diff / HZ);
871 b->xid = d->xid;
872
873 /* add DHCP options or BOOTP extensions */
874 #ifdef IPCONFIG_DHCP
875 if (ic_proto_enabled & IC_USE_DHCP)
876 ic_dhcp_init_options(b->exten, d);
877 else
878 #endif
879 ic_bootp_init_ext(b->exten);
880
881 /* Chain packet down the line... */
882 skb->dev = dev;
883 skb->protocol = htons(ETH_P_IP);
884 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
885 dev->broadcast, dev->dev_addr, skb->len) < 0) {
886 kfree_skb(skb);
887 printk("E");
888 return;
889 }
890
891 if (dev_queue_xmit(skb) < 0)
892 printk("E");
893 }
894
895
896 /*
897 * Copy BOOTP-supplied string
898 */
ic_bootp_string(char * dest,char * src,int len,int max)899 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
900 {
901 if (!len)
902 return 0;
903 if (len > max-1)
904 len = max-1;
905 memcpy(dest, src, len);
906 dest[len] = '\0';
907 return 1;
908 }
909
910
911 /*
912 * Process BOOTP extensions.
913 */
ic_do_bootp_ext(u8 * ext)914 static void __init ic_do_bootp_ext(u8 *ext)
915 {
916 u8 servers;
917 int i;
918 __be16 mtu;
919
920 u8 *c;
921
922 pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
923 for (c=ext+2; c<ext+2+ext[1]; c++)
924 pr_debug(" %02x", *c);
925 pr_debug("\n");
926
927 switch (*ext++) {
928 case 1: /* Subnet mask */
929 if (ic_netmask == NONE)
930 memcpy(&ic_netmask, ext+1, 4);
931 break;
932 case 3: /* Default gateway */
933 if (ic_gateway == NONE)
934 memcpy(&ic_gateway, ext+1, 4);
935 break;
936 case 6: /* DNS server */
937 servers= *ext/4;
938 if (servers > CONF_NAMESERVERS_MAX)
939 servers = CONF_NAMESERVERS_MAX;
940 for (i = 0; i < servers; i++) {
941 if (ic_nameservers[i] == NONE)
942 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
943 }
944 break;
945 case 12: /* Host name */
946 if (!ic_host_name_set) {
947 ic_bootp_string(utsname()->nodename, ext+1, *ext,
948 __NEW_UTS_LEN);
949 ic_host_name_set = 1;
950 }
951 break;
952 case 15: /* Domain name (DNS) */
953 if (!ic_domain[0])
954 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
955 break;
956 case 17: /* Root path */
957 if (!root_server_path[0])
958 ic_bootp_string(root_server_path, ext+1, *ext,
959 sizeof(root_server_path));
960 break;
961 case 26: /* Interface MTU */
962 memcpy(&mtu, ext+1, sizeof(mtu));
963 ic_dev_mtu = ntohs(mtu);
964 break;
965 case 40: /* NIS Domain name (_not_ DNS) */
966 ic_bootp_string(utsname()->domainname, ext+1, *ext,
967 __NEW_UTS_LEN);
968 break;
969 case 42: /* NTP servers */
970 servers = *ext / 4;
971 if (servers > CONF_NTP_SERVERS_MAX)
972 servers = CONF_NTP_SERVERS_MAX;
973 for (i = 0; i < servers; i++) {
974 if (ic_ntp_servers[i] == NONE)
975 memcpy(&ic_ntp_servers[i], ext+1+4*i, 4);
976 }
977 break;
978 }
979 }
980
981
982 /*
983 * Receive BOOTP reply.
984 */
ic_bootp_recv(struct sk_buff * skb,struct net_device * dev,struct packet_type * pt,struct net_device * orig_dev)985 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
986 {
987 struct bootp_pkt *b;
988 struct iphdr *h;
989 struct ic_device *d;
990 int len, ext_len;
991
992 if (!net_eq(dev_net(dev), &init_net))
993 goto drop;
994
995 /* Perform verifications before taking the lock. */
996 if (skb->pkt_type == PACKET_OTHERHOST)
997 goto drop;
998
999 skb = skb_share_check(skb, GFP_ATOMIC);
1000 if (!skb)
1001 return NET_RX_DROP;
1002
1003 if (!pskb_may_pull(skb,
1004 sizeof(struct iphdr) +
1005 sizeof(struct udphdr)))
1006 goto drop;
1007
1008 b = (struct bootp_pkt *)skb_network_header(skb);
1009 h = &b->iph;
1010
1011 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
1012 goto drop;
1013
1014 /* Fragments are not supported */
1015 if (ip_is_fragment(h)) {
1016 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
1017 goto drop;
1018 }
1019
1020 if (skb->len < ntohs(h->tot_len))
1021 goto drop;
1022
1023 if (ip_fast_csum((char *) h, h->ihl))
1024 goto drop;
1025
1026 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
1027 goto drop;
1028
1029 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1030 goto drop;
1031
1032 len = ntohs(b->udph.len) - sizeof(struct udphdr);
1033 ext_len = len - (sizeof(*b) -
1034 sizeof(struct iphdr) -
1035 sizeof(struct udphdr) -
1036 sizeof(b->exten));
1037 if (ext_len < 0)
1038 goto drop;
1039
1040 /* Ok the front looks good, make sure we can get at the rest. */
1041 if (!pskb_may_pull(skb, skb->len))
1042 goto drop;
1043
1044 b = (struct bootp_pkt *)skb_network_header(skb);
1045 h = &b->iph;
1046
1047 /* One reply at a time, please. */
1048 spin_lock(&ic_recv_lock);
1049
1050 /* If we already have a reply, just drop the packet */
1051 if (ic_got_reply)
1052 goto drop_unlock;
1053
1054 /* Find the ic_device that the packet arrived on */
1055 d = ic_first_dev;
1056 while (d && d->dev != dev)
1057 d = d->next;
1058 if (!d)
1059 goto drop_unlock; /* should never happen */
1060
1061 /* Is it a reply to our BOOTP request? */
1062 if (b->op != BOOTP_REPLY ||
1063 b->xid != d->xid) {
1064 net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1065 d->dev->name, b->op, b->xid);
1066 goto drop_unlock;
1067 }
1068
1069 /* Parse extensions */
1070 if (ext_len >= 4 &&
1071 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1072 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1073 u8 *ext;
1074
1075 #ifdef IPCONFIG_DHCP
1076 if (ic_proto_enabled & IC_USE_DHCP) {
1077 __be32 server_id = NONE;
1078 int mt = 0;
1079
1080 ext = &b->exten[4];
1081 while (ext < end && *ext != 0xff) {
1082 u8 *opt = ext++;
1083 if (*opt == 0) /* Padding */
1084 continue;
1085 ext += *ext + 1;
1086 if (ext >= end)
1087 break;
1088 switch (*opt) {
1089 case 53: /* Message type */
1090 if (opt[1])
1091 mt = opt[2];
1092 break;
1093 case 54: /* Server ID (IP address) */
1094 if (opt[1] >= 4)
1095 memcpy(&server_id, opt + 2, 4);
1096 break;
1097 }
1098 }
1099
1100 pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name);
1101
1102 switch (mt) {
1103 case DHCPOFFER:
1104 /* While in the process of accepting one offer,
1105 * ignore all others.
1106 */
1107 if (ic_myaddr != NONE)
1108 goto drop_unlock;
1109
1110 /* Let's accept that offer. */
1111 ic_myaddr = b->your_ip;
1112 ic_servaddr = server_id;
1113 pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1114 &ic_myaddr, &b->iph.saddr);
1115 /* The DHCP indicated server address takes
1116 * precedence over the bootp header one if
1117 * they are different.
1118 */
1119 if ((server_id != NONE) &&
1120 (b->server_ip != server_id))
1121 b->server_ip = ic_servaddr;
1122 break;
1123
1124 case DHCPACK:
1125 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1126 goto drop_unlock;
1127
1128 /* Yeah! */
1129 break;
1130
1131 default:
1132 /* Urque. Forget it*/
1133 ic_myaddr = NONE;
1134 ic_servaddr = NONE;
1135 goto drop_unlock;
1136 }
1137
1138 ic_dhcp_msgtype = mt;
1139
1140 }
1141 #endif /* IPCONFIG_DHCP */
1142
1143 ext = &b->exten[4];
1144 while (ext < end && *ext != 0xff) {
1145 u8 *opt = ext++;
1146 if (*opt == 0) /* Padding */
1147 continue;
1148 ext += *ext + 1;
1149 if (ext < end)
1150 ic_do_bootp_ext(opt);
1151 }
1152 }
1153
1154 /* We have a winner! */
1155 ic_dev = d;
1156 ic_myaddr = b->your_ip;
1157 ic_servaddr = b->server_ip;
1158 ic_addrservaddr = b->iph.saddr;
1159 if (ic_gateway == NONE && b->relay_ip)
1160 ic_gateway = b->relay_ip;
1161 if (ic_nameservers[0] == NONE)
1162 ic_nameservers[0] = ic_servaddr;
1163 ic_got_reply = IC_BOOTP;
1164
1165 drop_unlock:
1166 /* Show's over. Nothing to see here. */
1167 spin_unlock(&ic_recv_lock);
1168
1169 drop:
1170 /* Throw the packet out. */
1171 kfree_skb(skb);
1172
1173 return 0;
1174 }
1175
1176
1177 #endif
1178
1179
1180 /*
1181 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1182 */
1183
1184 #ifdef IPCONFIG_DYNAMIC
1185
ic_dynamic(void)1186 static int __init ic_dynamic(void)
1187 {
1188 int retries;
1189 struct ic_device *d;
1190 unsigned long start_jiffies, timeout, jiff;
1191 int do_bootp = ic_proto_have_if & IC_BOOTP;
1192 int do_rarp = ic_proto_have_if & IC_RARP;
1193
1194 /*
1195 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1196 * This routine gets only called when some pieces of information
1197 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1198 */
1199 if (!ic_proto_enabled) {
1200 pr_err("IP-Config: Incomplete network configuration information\n");
1201 return -1;
1202 }
1203
1204 #ifdef IPCONFIG_BOOTP
1205 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1206 pr_err("DHCP/BOOTP: No suitable device found\n");
1207 #endif
1208 #ifdef IPCONFIG_RARP
1209 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1210 pr_err("RARP: No suitable device found\n");
1211 #endif
1212
1213 if (!ic_proto_have_if)
1214 /* Error message already printed */
1215 return -1;
1216
1217 /*
1218 * Setup protocols
1219 */
1220 #ifdef IPCONFIG_BOOTP
1221 if (do_bootp)
1222 ic_bootp_init();
1223 #endif
1224 #ifdef IPCONFIG_RARP
1225 if (do_rarp)
1226 ic_rarp_init();
1227 #endif
1228
1229 /*
1230 * Send requests and wait, until we get an answer. This loop
1231 * seems to be a terrible waste of CPU time, but actually there is
1232 * only one process running at all, so we don't need to use any
1233 * scheduler functions.
1234 * [Actually we could now, but the nothing else running note still
1235 * applies.. - AC]
1236 */
1237 pr_notice("Sending %s%s%s requests .",
1238 do_bootp
1239 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1240 (do_bootp && do_rarp) ? " and " : "",
1241 do_rarp ? "RARP" : "");
1242
1243 start_jiffies = jiffies;
1244 d = ic_first_dev;
1245 retries = CONF_SEND_RETRIES;
1246 get_random_bytes(&timeout, sizeof(timeout));
1247 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1248 for (;;) {
1249 #ifdef IPCONFIG_BOOTP
1250 if (do_bootp && (d->able & IC_BOOTP))
1251 ic_bootp_send_if(d, jiffies - start_jiffies);
1252 #endif
1253 #ifdef IPCONFIG_RARP
1254 if (do_rarp && (d->able & IC_RARP))
1255 ic_rarp_send_if(d);
1256 #endif
1257
1258 if (!d->next) {
1259 jiff = jiffies + timeout;
1260 while (time_before(jiffies, jiff) && !ic_got_reply)
1261 schedule_timeout_uninterruptible(1);
1262 }
1263 #ifdef IPCONFIG_DHCP
1264 /* DHCP isn't done until we get a DHCPACK. */
1265 if ((ic_got_reply & IC_BOOTP) &&
1266 (ic_proto_enabled & IC_USE_DHCP) &&
1267 ic_dhcp_msgtype != DHCPACK) {
1268 ic_got_reply = 0;
1269 /* continue on device that got the reply */
1270 d = ic_dev;
1271 pr_cont(",");
1272 continue;
1273 }
1274 #endif /* IPCONFIG_DHCP */
1275
1276 if (ic_got_reply) {
1277 pr_cont(" OK\n");
1278 break;
1279 }
1280
1281 if ((d = d->next))
1282 continue;
1283
1284 if (! --retries) {
1285 pr_cont(" timed out!\n");
1286 break;
1287 }
1288
1289 d = ic_first_dev;
1290
1291 timeout = timeout CONF_TIMEOUT_MULT;
1292 if (timeout > CONF_TIMEOUT_MAX)
1293 timeout = CONF_TIMEOUT_MAX;
1294
1295 pr_cont(".");
1296 }
1297
1298 #ifdef IPCONFIG_BOOTP
1299 if (do_bootp)
1300 ic_bootp_cleanup();
1301 #endif
1302 #ifdef IPCONFIG_RARP
1303 if (do_rarp)
1304 ic_rarp_cleanup();
1305 #endif
1306
1307 if (!ic_got_reply) {
1308 ic_myaddr = NONE;
1309 return -1;
1310 }
1311
1312 pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1313 ((ic_got_reply & IC_RARP) ? "RARP"
1314 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1315 &ic_addrservaddr, &ic_myaddr);
1316
1317 return 0;
1318 }
1319
1320 #endif /* IPCONFIG_DYNAMIC */
1321
1322 #ifdef CONFIG_PROC_FS
1323 /* proc_dir_entry for /proc/net/ipconfig */
1324 static struct proc_dir_entry *ipconfig_dir;
1325
1326 /* Name servers: */
pnp_seq_show(struct seq_file * seq,void * v)1327 static int pnp_seq_show(struct seq_file *seq, void *v)
1328 {
1329 int i;
1330
1331 if (ic_proto_used & IC_PROTO)
1332 seq_printf(seq, "#PROTO: %s\n",
1333 (ic_proto_used & IC_RARP) ? "RARP"
1334 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1335 else
1336 seq_puts(seq, "#MANUAL\n");
1337
1338 if (ic_domain[0])
1339 seq_printf(seq,
1340 "domain %s\n", ic_domain);
1341 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1342 if (ic_nameservers[i] != NONE)
1343 seq_printf(seq, "nameserver %pI4\n",
1344 &ic_nameservers[i]);
1345 }
1346 if (ic_servaddr != NONE)
1347 seq_printf(seq, "bootserver %pI4\n",
1348 &ic_servaddr);
1349 return 0;
1350 }
1351
1352 /* Create the /proc/net/ipconfig directory */
ipconfig_proc_net_init(void)1353 static int __init ipconfig_proc_net_init(void)
1354 {
1355 ipconfig_dir = proc_net_mkdir(&init_net, "ipconfig", init_net.proc_net);
1356 if (!ipconfig_dir)
1357 return -ENOMEM;
1358
1359 return 0;
1360 }
1361
1362 /* Create a new file under /proc/net/ipconfig */
ipconfig_proc_net_create(const char * name,const struct proc_ops * proc_ops)1363 static int ipconfig_proc_net_create(const char *name,
1364 const struct proc_ops *proc_ops)
1365 {
1366 char *pname;
1367 struct proc_dir_entry *p;
1368
1369 if (!ipconfig_dir)
1370 return -ENOMEM;
1371
1372 pname = kasprintf(GFP_KERNEL, "%s%s", "ipconfig/", name);
1373 if (!pname)
1374 return -ENOMEM;
1375
1376 p = proc_create(pname, 0444, init_net.proc_net, proc_ops);
1377 kfree(pname);
1378 if (!p)
1379 return -ENOMEM;
1380
1381 return 0;
1382 }
1383
1384 /* Write NTP server IP addresses to /proc/net/ipconfig/ntp_servers */
ntp_servers_show(struct seq_file * seq,void * v)1385 static int ntp_servers_show(struct seq_file *seq, void *v)
1386 {
1387 int i;
1388
1389 for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1390 if (ic_ntp_servers[i] != NONE)
1391 seq_printf(seq, "%pI4\n", &ic_ntp_servers[i]);
1392 }
1393 return 0;
1394 }
1395 DEFINE_PROC_SHOW_ATTRIBUTE(ntp_servers);
1396 #endif /* CONFIG_PROC_FS */
1397
1398 /*
1399 * Extract IP address from the parameter string if needed. Note that we
1400 * need to have root_server_addr set _before_ IPConfig gets called as it
1401 * can override it.
1402 */
root_nfs_parse_addr(char * name)1403 __be32 __init root_nfs_parse_addr(char *name)
1404 {
1405 __be32 addr;
1406 int octets = 0;
1407 char *cp, *cq;
1408
1409 cp = cq = name;
1410 while (octets < 4) {
1411 while (*cp >= '0' && *cp <= '9')
1412 cp++;
1413 if (cp == cq || cp - cq > 3)
1414 break;
1415 if (*cp == '.' || octets == 3)
1416 octets++;
1417 if (octets < 4)
1418 cp++;
1419 cq = cp;
1420 }
1421 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1422 if (*cp == ':')
1423 *cp++ = '\0';
1424 addr = in_aton(name);
1425 memmove(name, cp, strlen(cp) + 1);
1426 } else
1427 addr = NONE;
1428
1429 return addr;
1430 }
1431
1432 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1433
wait_for_devices(void)1434 static int __init wait_for_devices(void)
1435 {
1436 int i;
1437 bool try_init_devs = true;
1438
1439 for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1440 struct net_device *dev;
1441 int found = 0;
1442
1443 /* make sure deferred device probes are finished */
1444 wait_for_device_probe();
1445
1446 rtnl_lock();
1447 for_each_netdev(&init_net, dev) {
1448 if (ic_is_init_dev(dev)) {
1449 found = 1;
1450 break;
1451 }
1452 }
1453 rtnl_unlock();
1454 if (found)
1455 return 0;
1456 if (try_init_devs &&
1457 (ROOT_DEV == Root_NFS || ROOT_DEV == Root_CIFS)) {
1458 try_init_devs = false;
1459 wait_for_init_devices_probe();
1460 }
1461 ssleep(1);
1462 }
1463 return -ENODEV;
1464 }
1465
1466 /*
1467 * IP Autoconfig dispatcher.
1468 */
1469
ip_auto_config(void)1470 static int __init ip_auto_config(void)
1471 {
1472 __be32 addr;
1473 #ifdef IPCONFIG_DYNAMIC
1474 int retries = CONF_OPEN_RETRIES;
1475 #endif
1476 int err;
1477 unsigned int i, count;
1478
1479 /* Initialise all name servers and NTP servers to NONE (but only if the
1480 * "ip=" or "nfsaddrs=" kernel command line parameters weren't decoded,
1481 * otherwise we'll overwrite the IP addresses specified there)
1482 */
1483 if (ic_set_manually == 0) {
1484 ic_nameservers_predef();
1485 ic_ntp_servers_predef();
1486 }
1487
1488 #ifdef CONFIG_PROC_FS
1489 proc_create_single("pnp", 0444, init_net.proc_net, pnp_seq_show);
1490
1491 if (ipconfig_proc_net_init() == 0)
1492 ipconfig_proc_net_create("ntp_servers", &ntp_servers_proc_ops);
1493 #endif /* CONFIG_PROC_FS */
1494
1495 if (!ic_enable)
1496 return 0;
1497
1498 pr_debug("IP-Config: Entered.\n");
1499 #ifdef IPCONFIG_DYNAMIC
1500 try_try_again:
1501 #endif
1502 /* Wait for devices to appear */
1503 err = wait_for_devices();
1504 if (err)
1505 return err;
1506
1507 /* Setup all network devices */
1508 err = ic_open_devs();
1509 if (err)
1510 return err;
1511
1512 /* Give drivers a chance to settle */
1513 msleep(CONF_POST_OPEN);
1514
1515 /*
1516 * If the config information is insufficient (e.g., our IP address or
1517 * IP address of the boot server is missing or we have multiple network
1518 * interfaces and no default was set), use BOOTP or RARP to get the
1519 * missing values.
1520 */
1521 if (ic_myaddr == NONE ||
1522 #if defined(CONFIG_ROOT_NFS) || defined(CONFIG_CIFS_ROOT)
1523 (root_server_addr == NONE &&
1524 ic_servaddr == NONE &&
1525 (ROOT_DEV == Root_NFS || ROOT_DEV == Root_CIFS)) ||
1526 #endif
1527 ic_first_dev->next) {
1528 #ifdef IPCONFIG_DYNAMIC
1529 if (ic_dynamic() < 0) {
1530 ic_close_devs();
1531
1532 /*
1533 * I don't know why, but sometimes the
1534 * eepro100 driver (at least) gets upset and
1535 * doesn't work the first time it's opened.
1536 * But then if you close it and reopen it, it
1537 * works just fine. So we need to try that at
1538 * least once before giving up.
1539 *
1540 * Also, if the root will be NFS-mounted, we
1541 * have nowhere to go if DHCP fails. So we
1542 * just have to keep trying forever.
1543 *
1544 * -- Chip
1545 */
1546 #ifdef CONFIG_ROOT_NFS
1547 if (ROOT_DEV == Root_NFS) {
1548 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1549 goto try_try_again;
1550 }
1551 #endif
1552 #ifdef CONFIG_CIFS_ROOT
1553 if (ROOT_DEV == Root_CIFS) {
1554 pr_err("IP-Config: Retrying forever (CIFS root)...\n");
1555 goto try_try_again;
1556 }
1557 #endif
1558
1559 if (--retries) {
1560 pr_err("IP-Config: Reopening network devices...\n");
1561 goto try_try_again;
1562 }
1563
1564 /* Oh, well. At least we tried. */
1565 pr_err("IP-Config: Auto-configuration of network failed\n");
1566 return -1;
1567 }
1568 #else /* !DYNAMIC */
1569 pr_err("IP-Config: Incomplete network configuration information\n");
1570 ic_close_devs();
1571 return -1;
1572 #endif /* IPCONFIG_DYNAMIC */
1573 } else {
1574 /* Device selected manually or only one device -> use it */
1575 ic_dev = ic_first_dev;
1576 }
1577
1578 addr = root_nfs_parse_addr(root_server_path);
1579 if (root_server_addr == NONE)
1580 root_server_addr = addr;
1581
1582 /*
1583 * Use defaults wherever applicable.
1584 */
1585 if (ic_defaults() < 0)
1586 return -1;
1587
1588 /*
1589 * Record which protocol was actually used.
1590 */
1591 #ifdef IPCONFIG_DYNAMIC
1592 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1593 #endif
1594
1595 #ifndef IPCONFIG_SILENT
1596 /*
1597 * Clue in the operator.
1598 */
1599 pr_info("IP-Config: Complete:\n");
1600
1601 pr_info(" device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1602 ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1603 &ic_myaddr, &ic_netmask, &ic_gateway);
1604 pr_info(" host=%s, domain=%s, nis-domain=%s\n",
1605 utsname()->nodename, ic_domain, utsname()->domainname);
1606 pr_info(" bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1607 &ic_servaddr, &root_server_addr, root_server_path);
1608 if (ic_dev_mtu)
1609 pr_cont(", mtu=%d", ic_dev_mtu);
1610 /* Name servers (if any): */
1611 for (i = 0, count = 0; i < CONF_NAMESERVERS_MAX; i++) {
1612 if (ic_nameservers[i] != NONE) {
1613 if (i == 0)
1614 pr_info(" nameserver%u=%pI4",
1615 i, &ic_nameservers[i]);
1616 else
1617 pr_cont(", nameserver%u=%pI4",
1618 i, &ic_nameservers[i]);
1619
1620 count++;
1621 }
1622 if ((i + 1 == CONF_NAMESERVERS_MAX) && count > 0)
1623 pr_cont("\n");
1624 }
1625 /* NTP servers (if any): */
1626 for (i = 0, count = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1627 if (ic_ntp_servers[i] != NONE) {
1628 if (i == 0)
1629 pr_info(" ntpserver%u=%pI4",
1630 i, &ic_ntp_servers[i]);
1631 else
1632 pr_cont(", ntpserver%u=%pI4",
1633 i, &ic_ntp_servers[i]);
1634
1635 count++;
1636 }
1637 if ((i + 1 == CONF_NTP_SERVERS_MAX) && count > 0)
1638 pr_cont("\n");
1639 }
1640 #endif /* !SILENT */
1641
1642 /*
1643 * Close all network devices except the device we've
1644 * autoconfigured and set up routes.
1645 */
1646 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1647 err = -1;
1648 else
1649 err = 0;
1650
1651 ic_close_devs();
1652
1653 return err;
1654 }
1655
1656 late_initcall(ip_auto_config);
1657
1658
1659 /*
1660 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1661 * command line parameter. See Documentation/admin-guide/nfs/nfsroot.rst.
1662 */
ic_proto_name(char * name)1663 static int __init ic_proto_name(char *name)
1664 {
1665 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1666 return 1;
1667 }
1668 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1669 return 0;
1670 }
1671 #ifdef CONFIG_IP_PNP_DHCP
1672 else if (!strncmp(name, "dhcp", 4)) {
1673 char *client_id;
1674
1675 ic_proto_enabled &= ~IC_RARP;
1676 client_id = strstr(name, "dhcp,");
1677 if (client_id) {
1678 char *v;
1679
1680 client_id = client_id + 5;
1681 v = strchr(client_id, ',');
1682 if (!v)
1683 return 1;
1684 *v = 0;
1685 if (kstrtou8(client_id, 0, dhcp_client_identifier))
1686 pr_debug("DHCP: Invalid client identifier type\n");
1687 strncpy(dhcp_client_identifier + 1, v + 1, 251);
1688 *v = ',';
1689 }
1690 return 1;
1691 }
1692 #endif
1693 #ifdef CONFIG_IP_PNP_BOOTP
1694 else if (!strcmp(name, "bootp")) {
1695 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1696 return 1;
1697 }
1698 #endif
1699 #ifdef CONFIG_IP_PNP_RARP
1700 else if (!strcmp(name, "rarp")) {
1701 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1702 return 1;
1703 }
1704 #endif
1705 #ifdef IPCONFIG_DYNAMIC
1706 else if (!strcmp(name, "both")) {
1707 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1708 return 1;
1709 }
1710 #endif
1711 return 0;
1712 }
1713
ip_auto_config_setup(char * addrs)1714 static int __init ip_auto_config_setup(char *addrs)
1715 {
1716 char *cp, *ip, *dp;
1717 int num = 0;
1718
1719 ic_set_manually = 1;
1720 ic_enable = 1;
1721
1722 /*
1723 * If any dhcp, bootp etc options are set, leave autoconfig on
1724 * and skip the below static IP processing.
1725 */
1726 if (ic_proto_name(addrs))
1727 return 1;
1728
1729 /* If no static IP is given, turn off autoconfig and bail. */
1730 if (*addrs == 0 ||
1731 strcmp(addrs, "off") == 0 ||
1732 strcmp(addrs, "none") == 0) {
1733 ic_enable = 0;
1734 return 1;
1735 }
1736
1737 /* Initialise all name servers and NTP servers to NONE */
1738 ic_nameservers_predef();
1739 ic_ntp_servers_predef();
1740
1741 /* Parse string for static IP assignment. */
1742 ip = addrs;
1743 while (ip && *ip) {
1744 if ((cp = strchr(ip, ':')))
1745 *cp++ = '\0';
1746 if (strlen(ip) > 0) {
1747 pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1748 switch (num) {
1749 case 0:
1750 if ((ic_myaddr = in_aton(ip)) == ANY)
1751 ic_myaddr = NONE;
1752 break;
1753 case 1:
1754 if ((ic_servaddr = in_aton(ip)) == ANY)
1755 ic_servaddr = NONE;
1756 break;
1757 case 2:
1758 if ((ic_gateway = in_aton(ip)) == ANY)
1759 ic_gateway = NONE;
1760 break;
1761 case 3:
1762 if ((ic_netmask = in_aton(ip)) == ANY)
1763 ic_netmask = NONE;
1764 break;
1765 case 4:
1766 if ((dp = strchr(ip, '.'))) {
1767 *dp++ = '\0';
1768 strscpy(utsname()->domainname, dp,
1769 sizeof(utsname()->domainname));
1770 }
1771 strscpy(utsname()->nodename, ip,
1772 sizeof(utsname()->nodename));
1773 ic_host_name_set = 1;
1774 break;
1775 case 5:
1776 strscpy(user_dev_name, ip, sizeof(user_dev_name));
1777 break;
1778 case 6:
1779 if (ic_proto_name(ip) == 0 &&
1780 ic_myaddr == NONE) {
1781 ic_enable = 0;
1782 }
1783 break;
1784 case 7:
1785 if (CONF_NAMESERVERS_MAX >= 1) {
1786 ic_nameservers[0] = in_aton(ip);
1787 if (ic_nameservers[0] == ANY)
1788 ic_nameservers[0] = NONE;
1789 }
1790 break;
1791 case 8:
1792 if (CONF_NAMESERVERS_MAX >= 2) {
1793 ic_nameservers[1] = in_aton(ip);
1794 if (ic_nameservers[1] == ANY)
1795 ic_nameservers[1] = NONE;
1796 }
1797 break;
1798 case 9:
1799 if (CONF_NTP_SERVERS_MAX >= 1) {
1800 ic_ntp_servers[0] = in_aton(ip);
1801 if (ic_ntp_servers[0] == ANY)
1802 ic_ntp_servers[0] = NONE;
1803 }
1804 break;
1805 }
1806 }
1807 ip = cp;
1808 num++;
1809 }
1810
1811 return 1;
1812 }
1813 __setup("ip=", ip_auto_config_setup);
1814
nfsaddrs_config_setup(char * addrs)1815 static int __init nfsaddrs_config_setup(char *addrs)
1816 {
1817 return ip_auto_config_setup(addrs);
1818 }
1819 __setup("nfsaddrs=", nfsaddrs_config_setup);
1820
vendor_class_identifier_setup(char * addrs)1821 static int __init vendor_class_identifier_setup(char *addrs)
1822 {
1823 if (strscpy(vendor_class_identifier, addrs,
1824 sizeof(vendor_class_identifier))
1825 >= sizeof(vendor_class_identifier))
1826 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1827 vendor_class_identifier);
1828 return 1;
1829 }
1830 __setup("dhcpclass=", vendor_class_identifier_setup);
1831
set_carrier_timeout(char * str)1832 static int __init set_carrier_timeout(char *str)
1833 {
1834 ssize_t ret;
1835
1836 if (!str)
1837 return 0;
1838
1839 ret = kstrtouint(str, 0, &carrier_timeout);
1840 if (ret)
1841 return 0;
1842
1843 return 1;
1844 }
1845 __setup("carrier_timeout=", set_carrier_timeout);
1846