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