2 * $Id: ipconfig.c,v 1.46 2002/02/01 22:01:04 davem Exp $
4 * Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
5 * user-supplied information to configure own IP address and routes.
7 * Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
9 * Derived from network configuration code in fs/nfs/nfsroot.c,
10 * originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
12 * BOOTP rewritten to construct and analyse packets itself instead
13 * of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
14 * -- MJ, December 1998
16 * Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
17 * initialization scheme.
18 * - Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
20 * DHCP support added. To users this looks like a whole separate
21 * protocol, but we know it's just a bag on the side of BOOTP.
22 * -- Chip Salzenberg <chip@valinux.com>, May 2000
24 * Ported DHCP support from 2.2.16 to 2.4.0-test4
25 * -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
27 * Merged changes from 2.2.19 into 2.4.3
28 * -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
30 * Multiple Nameservers in /proc/net/pnp
31 * -- Josef Siemes <jsiemes@web.de>, Aug 2002
34 #include <linux/types.h>
35 #include <linux/string.h>
36 #include <linux/kernel.h>
37 #include <linux/jiffies.h>
38 #include <linux/random.h>
39 #include <linux/init.h>
40 #include <linux/utsname.h>
43 #include <linux/inet.h>
44 #include <linux/inetdevice.h>
45 #include <linux/netdevice.h>
46 #include <linux/if_arp.h>
47 #include <linux/skbuff.h>
49 #include <linux/socket.h>
50 #include <linux/route.h>
51 #include <linux/udp.h>
52 #include <linux/proc_fs.h>
53 #include <linux/seq_file.h>
54 #include <linux/major.h>
55 #include <linux/root_dev.h>
56 #include <linux/delay.h>
57 #include <linux/nfs_fs.h>
58 #include <net/net_namespace.h>
61 #include <net/ipconfig.h>
62 #include <net/route.h>
64 #include <asm/uaccess.h>
65 #include <net/checksum.h>
66 #include <asm/processor.h>
68 /* Define this to allow debugging output */
72 #define DBG(x) printk x
74 #define DBG(x) do { } while(0)
77 #if defined(CONFIG_IP_PNP_DHCP)
80 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
81 #define IPCONFIG_BOOTP
83 #if defined(CONFIG_IP_PNP_RARP)
86 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
87 #define IPCONFIG_DYNAMIC
90 /* Define the friendly delay before and after opening net devices */
91 #define CONF_PRE_OPEN 500 /* Before opening: 1/2 second */
92 #define CONF_POST_OPEN 1 /* After opening: 1 second */
94 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
95 #define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */
96 #define CONF_SEND_RETRIES 6 /* Send six requests per open */
97 #define CONF_INTER_TIMEOUT (HZ/2) /* Inter-device timeout: 1/2 second */
98 #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
99 #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
100 #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
101 #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
102 #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
103 - '3' from resolv.h */
105 #define NONE __constant_htonl(INADDR_NONE)
108 * Public IP configuration
111 /* This is used by platforms which might be able to set the ipconfig
112 * variables using firmware environment vars. If this is set, it will
113 * ignore such firmware variables.
115 int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
117 static int ic_enable __initdata = 0; /* IP config enabled? */
119 /* Protocol choice */
120 int ic_proto_enabled __initdata = 0
121 #ifdef IPCONFIG_BOOTP
124 #ifdef CONFIG_IP_PNP_DHCP
132 static int ic_host_name_set __initdata = 0; /* Host name set by us? */
134 __be32 ic_myaddr = NONE; /* My IP address */
135 static __be32 ic_netmask = NONE; /* Netmask for local subnet */
136 __be32 ic_gateway = NONE; /* Gateway IP address */
138 __be32 ic_servaddr = NONE; /* Boot server IP address */
140 __be32 root_server_addr = NONE; /* Address of NFS server */
141 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
143 /* Persistent data: */
145 static int ic_proto_used; /* Protocol used, if any */
146 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
147 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
153 /* Name of user-selected boot device */
154 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
156 /* Protocols supported by available interfaces */
157 static int ic_proto_have_if __initdata = 0;
159 #ifdef IPCONFIG_DYNAMIC
160 static DEFINE_SPINLOCK(ic_recv_lock);
161 static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
164 static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
173 struct ic_device *next;
174 struct net_device *dev;
175 unsigned short flags;
180 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
181 static struct net_device *ic_dev __initdata = NULL; /* Selected device */
183 static int __init ic_open_devs(void)
185 struct ic_device *d, **last;
186 struct net_device *dev;
187 unsigned short oflags;
189 last = &ic_first_dev;
192 /* bring loopback device up first */
193 if (dev_change_flags(&loopback_dev, loopback_dev.flags | IFF_UP) < 0)
194 printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev.name);
196 for_each_netdev(dev) {
197 if (dev == &loopback_dev)
199 if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
200 (!(dev->flags & IFF_LOOPBACK) &&
201 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
202 strncmp(dev->name, "dummy", 5))) {
207 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
208 if (!(dev->flags & IFF_NOARP))
210 able &= ic_proto_enabled;
211 if (ic_proto_enabled && !able)
214 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
215 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
218 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
228 get_random_bytes(&d->xid, sizeof(__be32));
231 ic_proto_have_if |= able;
232 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
233 dev->name, able, d->xid));
241 if (user_dev_name[0])
242 printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
244 printk(KERN_ERR "IP-Config: No network devices available.\n");
250 static void __init ic_close_devs(void)
252 struct ic_device *d, *next;
253 struct net_device *dev;
261 DBG(("IP-Config: Downing %s\n", dev->name));
262 dev_change_flags(dev, d->flags);
270 * Interface to various network functions.
274 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
276 sin->sin_family = AF_INET;
277 sin->sin_addr.s_addr = addr;
278 sin->sin_port = port;
281 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
285 mm_segment_t oldfs = get_fs();
287 res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
292 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
296 mm_segment_t oldfs = get_fs();
298 res = ip_rt_ioctl(cmd, (void __user *) arg);
304 * Set up interface addresses and routes.
307 static int __init ic_setup_if(void)
310 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
313 memset(&ir, 0, sizeof(ir));
314 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
315 set_sockaddr(sin, ic_myaddr, 0);
316 if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
317 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
320 set_sockaddr(sin, ic_netmask, 0);
321 if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
322 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
325 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
326 if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
327 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
333 static int __init ic_setup_routes(void)
335 /* No need to setup device routes, only the default route... */
337 if (ic_gateway != NONE) {
341 memset(&rm, 0, sizeof(rm));
342 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
343 printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
346 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
347 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
348 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
349 rm.rt_flags = RTF_UP | RTF_GATEWAY;
350 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
351 printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
360 * Fill in default values for all missing parameters.
363 static int __init ic_defaults(void)
366 * At this point we have no userspace running so need not
367 * claim locks on system_utsname
370 if (!ic_host_name_set)
371 sprintf(init_utsname()->nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
373 if (root_server_addr == NONE)
374 root_server_addr = ic_servaddr;
376 if (ic_netmask == NONE) {
377 if (IN_CLASSA(ntohl(ic_myaddr)))
378 ic_netmask = htonl(IN_CLASSA_NET);
379 else if (IN_CLASSB(ntohl(ic_myaddr)))
380 ic_netmask = htonl(IN_CLASSB_NET);
381 else if (IN_CLASSC(ntohl(ic_myaddr)))
382 ic_netmask = htonl(IN_CLASSC_NET);
384 printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
388 printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
400 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
402 static struct packet_type rarp_packet_type __initdata = {
403 .type = __constant_htons(ETH_P_RARP),
404 .func = ic_rarp_recv,
407 static inline void ic_rarp_init(void)
409 dev_add_pack(&rarp_packet_type);
412 static inline void ic_rarp_cleanup(void)
414 dev_remove_pack(&rarp_packet_type);
418 * Process received RARP packet.
421 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
424 unsigned char *rarp_ptr;
426 unsigned char *sha, *tha; /* s for "source", t for "target" */
429 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
432 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
435 /* Basic sanity checks can be done without the lock. */
436 rarp = (struct arphdr *)skb_transport_header(skb);
438 /* If this test doesn't pass, it's not IP, or we should
441 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
444 /* If it's not a RARP reply, delete it. */
445 if (rarp->ar_op != htons(ARPOP_RREPLY))
448 /* If it's not Ethernet, delete it. */
449 if (rarp->ar_pro != htons(ETH_P_IP))
452 if (!pskb_may_pull(skb,
453 sizeof(struct arphdr) +
454 (2 * dev->addr_len) +
458 /* OK, it is all there and looks valid, process... */
459 rarp = (struct arphdr *)skb_transport_header(skb);
460 rarp_ptr = (unsigned char *) (rarp + 1);
462 /* One reply at a time, please. */
463 spin_lock(&ic_recv_lock);
465 /* If we already have a reply, just drop the packet */
469 /* Find the ic_device that the packet arrived on */
471 while (d && d->dev != dev)
474 goto drop_unlock; /* should never happen */
476 /* Extract variable-width fields */
478 rarp_ptr += dev->addr_len;
479 memcpy(&sip, rarp_ptr, 4);
482 rarp_ptr += dev->addr_len;
483 memcpy(&tip, rarp_ptr, 4);
485 /* Discard packets which are not meant for us. */
486 if (memcmp(tha, dev->dev_addr, dev->addr_len))
489 /* Discard packets which are not from specified server. */
490 if (ic_servaddr != NONE && ic_servaddr != sip)
493 /* We have a winner! */
495 if (ic_myaddr == NONE)
498 ic_got_reply = IC_RARP;
501 /* Show's over. Nothing to see here. */
502 spin_unlock(&ic_recv_lock);
505 /* Throw the packet out. */
512 * Send RARP request packet over a single interface.
514 static void __init ic_rarp_send_if(struct ic_device *d)
516 struct net_device *dev = d->dev;
517 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
518 dev->dev_addr, dev->dev_addr);
523 * DHCP/BOOTP support.
526 #ifdef IPCONFIG_BOOTP
528 struct bootp_pkt { /* BOOTP packet format */
529 struct iphdr iph; /* IP header */
530 struct udphdr udph; /* UDP header */
531 u8 op; /* 1=request, 2=reply */
532 u8 htype; /* HW address type */
533 u8 hlen; /* HW address length */
534 u8 hops; /* Used only by gateways */
535 __be32 xid; /* Transaction ID */
536 __be16 secs; /* Seconds since we started */
537 __be16 flags; /* Just what it says */
538 __be32 client_ip; /* Client's IP address if known */
539 __be32 your_ip; /* Assigned IP address */
540 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
541 __be32 relay_ip; /* IP address of BOOTP relay */
542 u8 hw_addr[16]; /* Client's HW address */
543 u8 serv_name[64]; /* Server host name */
544 u8 boot_file[128]; /* Name of boot file */
545 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
549 #define BOOTP_REQUEST 1
550 #define BOOTP_REPLY 2
552 /* DHCP message types */
553 #define DHCPDISCOVER 1
555 #define DHCPREQUEST 3
556 #define DHCPDECLINE 4
559 #define DHCPRELEASE 7
562 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
564 static struct packet_type bootp_packet_type __initdata = {
565 .type = __constant_htons(ETH_P_IP),
566 .func = ic_bootp_recv,
571 * Initialize DHCP/BOOTP extension fields in the request.
574 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
579 ic_dhcp_init_options(u8 *options)
581 u8 mt = ((ic_servaddr == NONE)
582 ? DHCPDISCOVER : DHCPREQUEST);
585 #ifdef IPCONFIG_DEBUG
586 printk("DHCP: Sending message type %d\n", mt);
589 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
592 *e++ = 53; /* DHCP message type */
596 if (mt == DHCPREQUEST) {
597 *e++ = 54; /* Server ID (IP address) */
599 memcpy(e, &ic_servaddr, 4);
602 *e++ = 50; /* Requested IP address */
604 memcpy(e, &ic_myaddr, 4);
610 static const u8 ic_req_params[] = {
612 3, /* Default gateway */
615 15, /* Domain name */
617 40, /* NIS domain name */
620 *e++ = 55; /* Parameter request list */
621 *e++ = sizeof(ic_req_params);
622 memcpy(e, ic_req_params, sizeof(ic_req_params));
623 e += sizeof(ic_req_params);
626 *e++ = 255; /* End of the list */
629 #endif /* IPCONFIG_DHCP */
631 static void __init ic_bootp_init_ext(u8 *e)
633 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
635 *e++ = 1; /* Subnet mask request */
638 *e++ = 3; /* Default gateway request */
641 *e++ = 5; /* Name server request */
644 *e++ = 12; /* Host name request */
647 *e++ = 40; /* NIS Domain name request */
650 *e++ = 17; /* Boot path */
654 *e++ = 57; /* set extension buffer size for reply */
656 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
659 *e++ = 255; /* End of the list */
664 * Initialize the DHCP/BOOTP mechanism.
666 static inline void ic_bootp_init(void)
670 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
671 ic_nameservers[i] = NONE;
673 dev_add_pack(&bootp_packet_type);
678 * DHCP/BOOTP cleanup.
680 static inline void ic_bootp_cleanup(void)
682 dev_remove_pack(&bootp_packet_type);
687 * Send DHCP/BOOTP request to single interface.
689 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
691 struct net_device *dev = d->dev;
694 int hh_len = LL_RESERVED_SPACE(dev);
697 /* Allocate packet */
698 skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
701 skb_reserve(skb, hh_len);
702 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
703 memset(b, 0, sizeof(struct bootp_pkt));
705 /* Construct IP header */
706 skb_reset_network_header(skb);
710 h->tot_len = htons(sizeof(struct bootp_pkt));
711 h->frag_off = htons(IP_DF);
713 h->protocol = IPPROTO_UDP;
714 h->daddr = htonl(INADDR_BROADCAST);
715 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
717 /* Construct UDP header */
718 b->udph.source = htons(68);
719 b->udph.dest = htons(67);
720 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
721 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
723 /* Construct DHCP/BOOTP header */
724 b->op = BOOTP_REQUEST;
725 if (dev->type < 256) /* check for false types */
726 b->htype = dev->type;
727 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
728 b->htype = ARPHRD_IEEE802;
729 else if (dev->type == ARPHRD_FDDI)
730 b->htype = ARPHRD_ETHER;
732 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
733 b->htype = dev->type; /* can cause undefined behavior */
735 b->hlen = dev->addr_len;
738 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
739 b->secs = htons(jiffies_diff / HZ);
742 /* add DHCP options or BOOTP extensions */
744 if (ic_proto_enabled & IC_USE_DHCP)
745 ic_dhcp_init_options(b->exten);
748 ic_bootp_init_ext(b->exten);
750 /* Chain packet down the line... */
752 skb->protocol = htons(ETH_P_IP);
753 if ((dev->hard_header &&
754 dev->hard_header(skb, dev, ntohs(skb->protocol), dev->broadcast, dev->dev_addr, skb->len) < 0) ||
755 dev_queue_xmit(skb) < 0)
761 * Copy BOOTP-supplied string if not already set.
763 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
769 memcpy(dest, src, len);
776 * Process BOOTP extensions.
778 static void __init ic_do_bootp_ext(u8 *ext)
783 #ifdef IPCONFIG_DEBUG
786 printk("DHCP/BOOTP: Got extension %d:",*ext);
787 for (c=ext+2; c<ext+2+ext[1]; c++)
793 case 1: /* Subnet mask */
794 if (ic_netmask == NONE)
795 memcpy(&ic_netmask, ext+1, 4);
797 case 3: /* Default gateway */
798 if (ic_gateway == NONE)
799 memcpy(&ic_gateway, ext+1, 4);
801 case 6: /* DNS server */
803 if (servers > CONF_NAMESERVERS_MAX)
804 servers = CONF_NAMESERVERS_MAX;
805 for (i = 0; i < servers; i++) {
806 if (ic_nameservers[i] == NONE)
807 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
810 case 12: /* Host name */
811 ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
812 ic_host_name_set = 1;
814 case 15: /* Domain name (DNS) */
815 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
817 case 17: /* Root path */
818 if (!root_server_path[0])
819 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
821 case 40: /* NIS Domain name (_not_ DNS) */
822 ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
829 * Receive BOOTP reply.
831 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
838 /* Perform verifications before taking the lock. */
839 if (skb->pkt_type == PACKET_OTHERHOST)
842 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
845 if (!pskb_may_pull(skb,
846 sizeof(struct iphdr) +
847 sizeof(struct udphdr)))
850 b = (struct bootp_pkt *)skb_network_header(skb);
853 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
856 /* Fragments are not supported */
857 if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
859 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
864 if (skb->len < ntohs(h->tot_len))
867 if (ip_fast_csum((char *) h, h->ihl))
870 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
873 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
876 len = ntohs(b->udph.len) - sizeof(struct udphdr);
877 ext_len = len - (sizeof(*b) -
878 sizeof(struct iphdr) -
879 sizeof(struct udphdr) -
884 /* Ok the front looks good, make sure we can get at the rest. */
885 if (!pskb_may_pull(skb, skb->len))
888 b = (struct bootp_pkt *)skb_network_header(skb);
891 /* One reply at a time, please. */
892 spin_lock(&ic_recv_lock);
894 /* If we already have a reply, just drop the packet */
898 /* Find the ic_device that the packet arrived on */
900 while (d && d->dev != dev)
903 goto drop_unlock; /* should never happen */
905 /* Is it a reply to our BOOTP request? */
906 if (b->op != BOOTP_REPLY ||
909 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
915 /* Parse extensions */
917 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
918 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
922 if (ic_proto_enabled & IC_USE_DHCP) {
923 __be32 server_id = NONE;
927 while (ext < end && *ext != 0xff) {
929 if (*opt == 0) /* Padding */
935 case 53: /* Message type */
939 case 54: /* Server ID (IP address) */
941 memcpy(&server_id, opt + 2, 4);
946 #ifdef IPCONFIG_DEBUG
947 printk("DHCP: Got message type %d\n", mt);
952 /* While in the process of accepting one offer,
955 if (ic_myaddr != NONE)
958 /* Let's accept that offer. */
959 ic_myaddr = b->your_ip;
960 ic_servaddr = server_id;
961 #ifdef IPCONFIG_DEBUG
962 printk("DHCP: Offered address %u.%u.%u.%u",
964 printk(" by server %u.%u.%u.%u\n",
965 NIPQUAD(ic_servaddr));
967 /* The DHCP indicated server address takes
968 * precedence over the bootp header one if
969 * they are different.
971 if ((server_id != NONE) &&
972 (b->server_ip != server_id))
973 b->server_ip = ic_servaddr;
977 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
984 /* Urque. Forget it*/
990 ic_dhcp_msgtype = mt;
993 #endif /* IPCONFIG_DHCP */
996 while (ext < end && *ext != 0xff) {
998 if (*opt == 0) /* Padding */
1002 ic_do_bootp_ext(opt);
1006 /* We have a winner! */
1008 ic_myaddr = b->your_ip;
1009 ic_servaddr = b->server_ip;
1010 if (ic_gateway == NONE && b->relay_ip)
1011 ic_gateway = b->relay_ip;
1012 if (ic_nameservers[0] == NONE)
1013 ic_nameservers[0] = ic_servaddr;
1014 ic_got_reply = IC_BOOTP;
1017 /* Show's over. Nothing to see here. */
1018 spin_unlock(&ic_recv_lock);
1021 /* Throw the packet out. */
1032 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1035 #ifdef IPCONFIG_DYNAMIC
1037 static int __init ic_dynamic(void)
1040 struct ic_device *d;
1041 unsigned long start_jiffies, timeout, jiff;
1042 int do_bootp = ic_proto_have_if & IC_BOOTP;
1043 int do_rarp = ic_proto_have_if & IC_RARP;
1046 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1047 * This routine gets only called when some pieces of information
1048 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1050 if (!ic_proto_enabled) {
1051 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1055 #ifdef IPCONFIG_BOOTP
1056 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1057 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1059 #ifdef IPCONFIG_RARP
1060 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1061 printk(KERN_ERR "RARP: No suitable device found.\n");
1064 if (!ic_proto_have_if)
1065 /* Error message already printed */
1071 #ifdef IPCONFIG_BOOTP
1075 #ifdef IPCONFIG_RARP
1081 * Send requests and wait, until we get an answer. This loop
1082 * seems to be a terrible waste of CPU time, but actually there is
1083 * only one process running at all, so we don't need to use any
1084 * scheduler functions.
1085 * [Actually we could now, but the nothing else running note still
1088 printk(KERN_NOTICE "Sending %s%s%s requests .",
1090 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1091 (do_bootp && do_rarp) ? " and " : "",
1092 do_rarp ? "RARP" : "");
1094 start_jiffies = jiffies;
1096 retries = CONF_SEND_RETRIES;
1097 get_random_bytes(&timeout, sizeof(timeout));
1098 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1100 #ifdef IPCONFIG_BOOTP
1101 if (do_bootp && (d->able & IC_BOOTP))
1102 ic_bootp_send_if(d, jiffies - start_jiffies);
1104 #ifdef IPCONFIG_RARP
1105 if (do_rarp && (d->able & IC_RARP))
1109 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1110 while (time_before(jiffies, jiff) && !ic_got_reply)
1111 schedule_timeout_uninterruptible(1);
1112 #ifdef IPCONFIG_DHCP
1113 /* DHCP isn't done until we get a DHCPACK. */
1114 if ((ic_got_reply & IC_BOOTP)
1115 && (ic_proto_enabled & IC_USE_DHCP)
1116 && ic_dhcp_msgtype != DHCPACK)
1122 #endif /* IPCONFIG_DHCP */
1133 printk(" timed out!\n");
1139 timeout = timeout CONF_TIMEOUT_MULT;
1140 if (timeout > CONF_TIMEOUT_MAX)
1141 timeout = CONF_TIMEOUT_MAX;
1146 #ifdef IPCONFIG_BOOTP
1150 #ifdef IPCONFIG_RARP
1155 if (!ic_got_reply) {
1160 printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1161 ((ic_got_reply & IC_RARP) ? "RARP"
1162 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1163 NIPQUAD(ic_servaddr));
1164 printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1169 #endif /* IPCONFIG_DYNAMIC */
1171 #ifdef CONFIG_PROC_FS
1173 static int pnp_seq_show(struct seq_file *seq, void *v)
1177 if (ic_proto_used & IC_PROTO)
1178 seq_printf(seq, "#PROTO: %s\n",
1179 (ic_proto_used & IC_RARP) ? "RARP"
1180 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1182 seq_puts(seq, "#MANUAL\n");
1186 "domain %s\n", ic_domain);
1187 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1188 if (ic_nameservers[i] != NONE)
1190 "nameserver %u.%u.%u.%u\n",
1191 NIPQUAD(ic_nameservers[i]));
1193 if (ic_servaddr != NONE)
1195 "bootserver %u.%u.%u.%u\n",
1196 NIPQUAD(ic_servaddr));
1200 static int pnp_seq_open(struct inode *indoe, struct file *file)
1202 return single_open(file, pnp_seq_show, NULL);
1205 static const struct file_operations pnp_seq_fops = {
1206 .owner = THIS_MODULE,
1207 .open = pnp_seq_open,
1209 .llseek = seq_lseek,
1210 .release = single_release,
1212 #endif /* CONFIG_PROC_FS */
1215 * Extract IP address from the parameter string if needed. Note that we
1216 * need to have root_server_addr set _before_ IPConfig gets called as it
1219 __be32 __init root_nfs_parse_addr(char *name)
1226 while (octets < 4) {
1227 while (*cp >= '0' && *cp <= '9')
1229 if (cp == cq || cp - cq > 3)
1231 if (*cp == '.' || octets == 3)
1237 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1240 addr = in_aton(name);
1241 memmove(name, cp, strlen(cp) + 1);
1249 * IP Autoconfig dispatcher.
1252 static int __init ip_auto_config(void)
1256 #ifdef CONFIG_PROC_FS
1257 proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1258 #endif /* CONFIG_PROC_FS */
1263 DBG(("IP-Config: Entered.\n"));
1264 #ifdef IPCONFIG_DYNAMIC
1267 /* Give hardware a chance to settle */
1268 msleep(CONF_PRE_OPEN);
1270 /* Setup all network devices */
1271 if (ic_open_devs() < 0)
1274 /* Give drivers a chance to settle */
1275 ssleep(CONF_POST_OPEN);
1278 * If the config information is insufficient (e.g., our IP address or
1279 * IP address of the boot server is missing or we have multiple network
1280 * interfaces and no default was set), use BOOTP or RARP to get the
1283 if (ic_myaddr == NONE ||
1284 #ifdef CONFIG_ROOT_NFS
1285 (root_server_addr == NONE
1286 && ic_servaddr == NONE
1287 && ROOT_DEV == Root_NFS) ||
1289 ic_first_dev->next) {
1290 #ifdef IPCONFIG_DYNAMIC
1292 int retries = CONF_OPEN_RETRIES;
1294 if (ic_dynamic() < 0) {
1298 * I don't know why, but sometimes the
1299 * eepro100 driver (at least) gets upset and
1300 * doesn't work the first time it's opened.
1301 * But then if you close it and reopen it, it
1302 * works just fine. So we need to try that at
1303 * least once before giving up.
1305 * Also, if the root will be NFS-mounted, we
1306 * have nowhere to go if DHCP fails. So we
1307 * just have to keep trying forever.
1311 #ifdef CONFIG_ROOT_NFS
1312 if (ROOT_DEV == Root_NFS) {
1314 "IP-Config: Retrying forever (NFS root)...\n");
1321 "IP-Config: Reopening network devices...\n");
1325 /* Oh, well. At least we tried. */
1326 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1329 #else /* !DYNAMIC */
1330 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1333 #endif /* IPCONFIG_DYNAMIC */
1335 /* Device selected manually or only one device -> use it */
1336 ic_dev = ic_first_dev->dev;
1339 addr = root_nfs_parse_addr(root_server_path);
1340 if (root_server_addr == NONE)
1341 root_server_addr = addr;
1344 * Use defaults whereever applicable.
1346 if (ic_defaults() < 0)
1350 * Close all network devices except the device we've
1351 * autoconfigured and set up routes.
1354 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1358 * Record which protocol was actually used.
1360 #ifdef IPCONFIG_DYNAMIC
1361 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1364 #ifndef IPCONFIG_SILENT
1366 * Clue in the operator.
1368 printk("IP-Config: Complete:");
1369 printk("\n device=%s", ic_dev->name);
1370 printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1371 printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1372 printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1373 printk(",\n host=%s, domain=%s, nis-domain=%s",
1374 utsname()->nodename, ic_domain, utsname()->domainname);
1375 printk(",\n bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1376 printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1377 printk(", rootpath=%s", root_server_path);
1379 #endif /* !SILENT */
1384 late_initcall(ip_auto_config);
1388 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1389 * command line parameter. It consists of option fields separated by colons in
1390 * the following order:
1392 * <client-ip>:<server-ip>:<gw-ip>:<netmask>:<host name>:<device>:<PROTO>
1394 * Any of the fields can be empty which means to use a default value:
1395 * <client-ip> - address given by BOOTP or RARP
1396 * <server-ip> - address of host returning BOOTP or RARP packet
1397 * <gw-ip> - none, or the address returned by BOOTP
1398 * <netmask> - automatically determined from <client-ip>, or the
1399 * one returned by BOOTP
1400 * <host name> - <client-ip> in ASCII notation, or the name returned
1402 * <device> - use all available devices
1404 * off|none - don't do autoconfig at all (DEFAULT)
1405 * on|any - use any configured protocol
1406 * dhcp|bootp|rarp - use only the specified protocol
1407 * both - use both BOOTP and RARP (not DHCP)
1409 static int __init ic_proto_name(char *name)
1411 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1414 #ifdef CONFIG_IP_PNP_DHCP
1415 else if (!strcmp(name, "dhcp")) {
1416 ic_proto_enabled &= ~IC_RARP;
1420 #ifdef CONFIG_IP_PNP_BOOTP
1421 else if (!strcmp(name, "bootp")) {
1422 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1426 #ifdef CONFIG_IP_PNP_RARP
1427 else if (!strcmp(name, "rarp")) {
1428 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1432 #ifdef IPCONFIG_DYNAMIC
1433 else if (!strcmp(name, "both")) {
1434 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1441 static int __init ip_auto_config_setup(char *addrs)
1446 ic_set_manually = 1;
1448 ic_enable = (*addrs &&
1449 (strcmp(addrs, "off") != 0) &&
1450 (strcmp(addrs, "none") != 0));
1454 if (ic_proto_name(addrs))
1457 /* Parse the whole string */
1460 if ((cp = strchr(ip, ':')))
1462 if (strlen(ip) > 0) {
1463 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1466 if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1470 if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1474 if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1478 if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1482 if ((dp = strchr(ip, '.'))) {
1484 strlcpy(utsname()->domainname, dp,
1485 sizeof(utsname()->domainname));
1487 strlcpy(utsname()->nodename, ip,
1488 sizeof(utsname()->nodename));
1489 ic_host_name_set = 1;
1492 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1506 static int __init nfsaddrs_config_setup(char *addrs)
1508 return ip_auto_config_setup(addrs);
1511 __setup("ip=", ip_auto_config_setup);
1512 __setup("nfsaddrs=", nfsaddrs_config_setup);