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