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>
60 #include <net/ipconfig.h>
61 #include <net/route.h>
63 #include <asm/uaccess.h>
64 #include <net/checksum.h>
65 #include <asm/processor.h>
67 /* Define this to allow debugging output */
71 #define DBG(x) printk x
73 #define DBG(x) do { } while(0)
76 #if defined(CONFIG_IP_PNP_DHCP)
79 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
80 #define IPCONFIG_BOOTP
82 #if defined(CONFIG_IP_PNP_RARP)
85 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
86 #define IPCONFIG_DYNAMIC
89 /* Define the friendly delay before and after opening net devices */
90 #define CONF_PRE_OPEN 500 /* Before opening: 1/2 second */
91 #define CONF_POST_OPEN 1 /* After opening: 1 second */
93 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
94 #define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */
95 #define CONF_SEND_RETRIES 6 /* Send six requests per open */
96 #define CONF_INTER_TIMEOUT (HZ/2) /* Inter-device timeout: 1/2 second */
97 #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
98 #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
99 #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
100 #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
101 #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
102 - '3' from resolv.h */
104 #define NONE __constant_htonl(INADDR_NONE)
107 * Public IP configuration
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.
114 int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
116 static int ic_enable __initdata = 0; /* IP config enabled? */
118 /* Protocol choice */
119 int ic_proto_enabled __initdata = 0
120 #ifdef IPCONFIG_BOOTP
123 #ifdef CONFIG_IP_PNP_DHCP
131 static int ic_host_name_set __initdata = 0; /* Host name set by us? */
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 */
137 __be32 ic_servaddr = NONE; /* Boot server IP address */
139 __be32 root_server_addr = NONE; /* Address of NFS server */
140 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
142 /* Persistent data: */
144 static int ic_proto_used; /* Protocol used, if any */
145 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
146 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
152 /* Name of user-selected boot device */
153 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
155 /* Protocols supported by available interfaces */
156 static int ic_proto_have_if __initdata = 0;
158 #ifdef IPCONFIG_DYNAMIC
159 static DEFINE_SPINLOCK(ic_recv_lock);
160 static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
163 static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
172 struct ic_device *next;
173 struct net_device *dev;
174 unsigned short flags;
179 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
180 static struct net_device *ic_dev __initdata = NULL; /* Selected device */
182 static int __init ic_open_devs(void)
184 struct ic_device *d, **last;
185 struct net_device *dev;
186 unsigned short oflags;
188 last = &ic_first_dev;
191 /* bring loopback device up first */
192 if (dev_change_flags(&loopback_dev, loopback_dev.flags | IFF_UP) < 0)
193 printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev.name);
195 for (dev = dev_base; dev; dev = dev->next) {
196 if (dev == &loopback_dev)
198 if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
199 (!(dev->flags & IFF_LOOPBACK) &&
200 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
201 strncmp(dev->name, "dummy", 5))) {
206 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
207 if (!(dev->flags & IFF_NOARP))
209 able &= ic_proto_enabled;
210 if (ic_proto_enabled && !able)
213 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
214 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
217 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
227 get_random_bytes(&d->xid, sizeof(__be32));
230 ic_proto_have_if |= able;
231 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
232 dev->name, able, d->xid));
240 if (user_dev_name[0])
241 printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
243 printk(KERN_ERR "IP-Config: No network devices available.\n");
249 static void __init ic_close_devs(void)
251 struct ic_device *d, *next;
252 struct net_device *dev;
260 DBG(("IP-Config: Downing %s\n", dev->name));
261 dev_change_flags(dev, d->flags);
269 * Interface to various network functions.
273 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
275 sin->sin_family = AF_INET;
276 sin->sin_addr.s_addr = addr;
277 sin->sin_port = port;
280 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
284 mm_segment_t oldfs = get_fs();
286 res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
291 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
295 mm_segment_t oldfs = get_fs();
297 res = ip_rt_ioctl(cmd, (void __user *) arg);
303 * Set up interface addresses and routes.
306 static int __init ic_setup_if(void)
309 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
312 memset(&ir, 0, sizeof(ir));
313 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
314 set_sockaddr(sin, ic_myaddr, 0);
315 if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
316 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
319 set_sockaddr(sin, ic_netmask, 0);
320 if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
321 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
324 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
325 if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
326 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
332 static int __init ic_setup_routes(void)
334 /* No need to setup device routes, only the default route... */
336 if (ic_gateway != NONE) {
340 memset(&rm, 0, sizeof(rm));
341 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
342 printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
345 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
346 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
347 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
348 rm.rt_flags = RTF_UP | RTF_GATEWAY;
349 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
350 printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
359 * Fill in default values for all missing parameters.
362 static int __init ic_defaults(void)
365 * At this point we have no userspace running so need not
366 * claim locks on system_utsname
369 if (!ic_host_name_set)
370 sprintf(init_utsname()->nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
372 if (root_server_addr == NONE)
373 root_server_addr = ic_servaddr;
375 if (ic_netmask == NONE) {
376 if (IN_CLASSA(ntohl(ic_myaddr)))
377 ic_netmask = htonl(IN_CLASSA_NET);
378 else if (IN_CLASSB(ntohl(ic_myaddr)))
379 ic_netmask = htonl(IN_CLASSB_NET);
380 else if (IN_CLASSC(ntohl(ic_myaddr)))
381 ic_netmask = htonl(IN_CLASSC_NET);
383 printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
387 printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
399 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
401 static struct packet_type rarp_packet_type __initdata = {
402 .type = __constant_htons(ETH_P_RARP),
403 .func = ic_rarp_recv,
406 static inline void ic_rarp_init(void)
408 dev_add_pack(&rarp_packet_type);
411 static inline void ic_rarp_cleanup(void)
413 dev_remove_pack(&rarp_packet_type);
417 * Process received RARP packet.
420 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
423 unsigned char *rarp_ptr;
425 unsigned char *sha, *tha; /* s for "source", t for "target" */
428 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
431 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
434 /* Basic sanity checks can be done without the lock. */
435 rarp = (struct arphdr *)skb->h.raw;
437 /* If this test doesn't pass, it's not IP, or we should
440 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
443 /* If it's not a RARP reply, delete it. */
444 if (rarp->ar_op != htons(ARPOP_RREPLY))
447 /* If it's not Ethernet, delete it. */
448 if (rarp->ar_pro != htons(ETH_P_IP))
451 if (!pskb_may_pull(skb,
452 sizeof(struct arphdr) +
453 (2 * dev->addr_len) +
457 /* OK, it is all there and looks valid, process... */
458 rarp = (struct arphdr *)skb->h.raw;
459 rarp_ptr = (unsigned char *) (rarp + 1);
461 /* One reply at a time, please. */
462 spin_lock(&ic_recv_lock);
464 /* If we already have a reply, just drop the packet */
468 /* Find the ic_device that the packet arrived on */
470 while (d && d->dev != dev)
473 goto drop_unlock; /* should never happen */
475 /* Extract variable-width fields */
477 rarp_ptr += dev->addr_len;
478 memcpy(&sip, rarp_ptr, 4);
481 rarp_ptr += dev->addr_len;
482 memcpy(&tip, rarp_ptr, 4);
484 /* Discard packets which are not meant for us. */
485 if (memcmp(tha, dev->dev_addr, dev->addr_len))
488 /* Discard packets which are not from specified server. */
489 if (ic_servaddr != NONE && ic_servaddr != sip)
492 /* We have a winner! */
494 if (ic_myaddr == NONE)
497 ic_got_reply = IC_RARP;
500 /* Show's over. Nothing to see here. */
501 spin_unlock(&ic_recv_lock);
504 /* Throw the packet out. */
511 * Send RARP request packet over a single interface.
513 static void __init ic_rarp_send_if(struct ic_device *d)
515 struct net_device *dev = d->dev;
516 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
517 dev->dev_addr, dev->dev_addr);
522 * DHCP/BOOTP support.
525 #ifdef IPCONFIG_BOOTP
527 struct bootp_pkt { /* BOOTP packet format */
528 struct iphdr iph; /* IP header */
529 struct udphdr udph; /* UDP header */
530 u8 op; /* 1=request, 2=reply */
531 u8 htype; /* HW address type */
532 u8 hlen; /* HW address length */
533 u8 hops; /* Used only by gateways */
534 __be32 xid; /* Transaction ID */
535 __be16 secs; /* Seconds since we started */
536 __be16 flags; /* Just what it says */
537 __be32 client_ip; /* Client's IP address if known */
538 __be32 your_ip; /* Assigned IP address */
539 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
540 __be32 relay_ip; /* IP address of BOOTP relay */
541 u8 hw_addr[16]; /* Client's HW address */
542 u8 serv_name[64]; /* Server host name */
543 u8 boot_file[128]; /* Name of boot file */
544 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
548 #define BOOTP_REQUEST 1
549 #define BOOTP_REPLY 2
551 /* DHCP message types */
552 #define DHCPDISCOVER 1
554 #define DHCPREQUEST 3
555 #define DHCPDECLINE 4
558 #define DHCPRELEASE 7
561 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
563 static struct packet_type bootp_packet_type __initdata = {
564 .type = __constant_htons(ETH_P_IP),
565 .func = ic_bootp_recv,
570 * Initialize DHCP/BOOTP extension fields in the request.
573 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
578 ic_dhcp_init_options(u8 *options)
580 u8 mt = ((ic_servaddr == NONE)
581 ? DHCPDISCOVER : DHCPREQUEST);
584 #ifdef IPCONFIG_DEBUG
585 printk("DHCP: Sending message type %d\n", mt);
588 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
591 *e++ = 53; /* DHCP message type */
595 if (mt == DHCPREQUEST) {
596 *e++ = 54; /* Server ID (IP address) */
598 memcpy(e, &ic_servaddr, 4);
601 *e++ = 50; /* Requested IP address */
603 memcpy(e, &ic_myaddr, 4);
609 static const u8 ic_req_params[] = {
611 3, /* Default gateway */
614 15, /* Domain name */
616 40, /* NIS domain name */
619 *e++ = 55; /* Parameter request list */
620 *e++ = sizeof(ic_req_params);
621 memcpy(e, ic_req_params, sizeof(ic_req_params));
622 e += sizeof(ic_req_params);
625 *e++ = 255; /* End of the list */
628 #endif /* IPCONFIG_DHCP */
630 static void __init ic_bootp_init_ext(u8 *e)
632 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
634 *e++ = 1; /* Subnet mask request */
637 *e++ = 3; /* Default gateway request */
640 *e++ = 5; /* Name server request */
643 *e++ = 12; /* Host name request */
646 *e++ = 40; /* NIS Domain name request */
649 *e++ = 17; /* Boot path */
653 *e++ = 57; /* set extension buffer size for reply */
655 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
658 *e++ = 255; /* End of the list */
663 * Initialize the DHCP/BOOTP mechanism.
665 static inline void ic_bootp_init(void)
669 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
670 ic_nameservers[i] = NONE;
672 dev_add_pack(&bootp_packet_type);
677 * DHCP/BOOTP cleanup.
679 static inline void ic_bootp_cleanup(void)
681 dev_remove_pack(&bootp_packet_type);
686 * Send DHCP/BOOTP request to single interface.
688 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
690 struct net_device *dev = d->dev;
693 int hh_len = LL_RESERVED_SPACE(dev);
696 /* Allocate packet */
697 skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
700 skb_reserve(skb, hh_len);
701 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
702 memset(b, 0, sizeof(struct bootp_pkt));
704 /* Construct IP header */
705 skb->nh.iph = h = &b->iph;
708 h->tot_len = htons(sizeof(struct bootp_pkt));
709 h->frag_off = htons(IP_DF);
711 h->protocol = IPPROTO_UDP;
712 h->daddr = htonl(INADDR_BROADCAST);
713 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
715 /* Construct UDP header */
716 b->udph.source = htons(68);
717 b->udph.dest = htons(67);
718 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
719 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
721 /* Construct DHCP/BOOTP header */
722 b->op = BOOTP_REQUEST;
723 if (dev->type < 256) /* check for false types */
724 b->htype = dev->type;
725 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
726 b->htype = ARPHRD_IEEE802;
727 else if (dev->type == ARPHRD_FDDI)
728 b->htype = ARPHRD_ETHER;
730 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
731 b->htype = dev->type; /* can cause undefined behavior */
733 b->hlen = dev->addr_len;
736 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
737 b->secs = htons(jiffies_diff / HZ);
740 /* add DHCP options or BOOTP extensions */
742 if (ic_proto_enabled & IC_USE_DHCP)
743 ic_dhcp_init_options(b->exten);
746 ic_bootp_init_ext(b->exten);
748 /* Chain packet down the line... */
750 skb->protocol = htons(ETH_P_IP);
751 if ((dev->hard_header &&
752 dev->hard_header(skb, dev, ntohs(skb->protocol), dev->broadcast, dev->dev_addr, skb->len) < 0) ||
753 dev_queue_xmit(skb) < 0)
759 * Copy BOOTP-supplied string if not already set.
761 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
767 memcpy(dest, src, len);
774 * Process BOOTP extensions.
776 static void __init ic_do_bootp_ext(u8 *ext)
781 #ifdef IPCONFIG_DEBUG
784 printk("DHCP/BOOTP: Got extension %d:",*ext);
785 for(c=ext+2; c<ext+2+ext[1]; c++)
791 case 1: /* Subnet mask */
792 if (ic_netmask == NONE)
793 memcpy(&ic_netmask, ext+1, 4);
795 case 3: /* Default gateway */
796 if (ic_gateway == NONE)
797 memcpy(&ic_gateway, ext+1, 4);
799 case 6: /* DNS server */
801 if (servers > CONF_NAMESERVERS_MAX)
802 servers = CONF_NAMESERVERS_MAX;
803 for (i = 0; i < servers; i++) {
804 if (ic_nameservers[i] == NONE)
805 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
808 case 12: /* Host name */
809 ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
810 ic_host_name_set = 1;
812 case 15: /* Domain name (DNS) */
813 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
815 case 17: /* Root path */
816 if (!root_server_path[0])
817 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
819 case 40: /* NIS Domain name (_not_ DNS) */
820 ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
827 * Receive BOOTP reply.
829 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
836 /* Perform verifications before taking the lock. */
837 if (skb->pkt_type == PACKET_OTHERHOST)
840 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
843 if (!pskb_may_pull(skb,
844 sizeof(struct iphdr) +
845 sizeof(struct udphdr)))
848 b = (struct bootp_pkt *) skb->nh.iph;
851 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
854 /* Fragments are not supported */
855 if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
857 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
862 if (skb->len < ntohs(h->tot_len))
865 if (ip_fast_csum((char *) h, h->ihl))
868 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
871 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
874 len = ntohs(b->udph.len) - sizeof(struct udphdr);
875 ext_len = len - (sizeof(*b) -
876 sizeof(struct iphdr) -
877 sizeof(struct udphdr) -
882 /* Ok the front looks good, make sure we can get at the rest. */
883 if (!pskb_may_pull(skb, skb->len))
886 b = (struct bootp_pkt *) skb->nh.iph;
889 /* One reply at a time, please. */
890 spin_lock(&ic_recv_lock);
892 /* If we already have a reply, just drop the packet */
896 /* Find the ic_device that the packet arrived on */
898 while (d && d->dev != dev)
901 goto drop_unlock; /* should never happen */
903 /* Is it a reply to our BOOTP request? */
904 if (b->op != BOOTP_REPLY ||
907 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
913 /* Parse extensions */
915 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
916 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
920 if (ic_proto_enabled & IC_USE_DHCP) {
921 __be32 server_id = NONE;
925 while (ext < end && *ext != 0xff) {
927 if (*opt == 0) /* Padding */
933 case 53: /* Message type */
937 case 54: /* Server ID (IP address) */
939 memcpy(&server_id, opt + 2, 4);
944 #ifdef IPCONFIG_DEBUG
945 printk("DHCP: Got message type %d\n", mt);
950 /* While in the process of accepting one offer,
953 if (ic_myaddr != NONE)
956 /* Let's accept that offer. */
957 ic_myaddr = b->your_ip;
958 ic_servaddr = server_id;
959 #ifdef IPCONFIG_DEBUG
960 printk("DHCP: Offered address %u.%u.%u.%u",
962 printk(" by server %u.%u.%u.%u\n",
963 NIPQUAD(ic_servaddr));
965 /* The DHCP indicated server address takes
966 * precedence over the bootp header one if
967 * they are different.
969 if ((server_id != NONE) &&
970 (b->server_ip != server_id))
971 b->server_ip = ic_servaddr;
975 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
982 /* Urque. Forget it*/
988 ic_dhcp_msgtype = mt;
991 #endif /* IPCONFIG_DHCP */
994 while (ext < end && *ext != 0xff) {
996 if (*opt == 0) /* Padding */
1000 ic_do_bootp_ext(opt);
1004 /* We have a winner! */
1006 ic_myaddr = b->your_ip;
1007 ic_servaddr = b->server_ip;
1008 if (ic_gateway == NONE && b->relay_ip)
1009 ic_gateway = b->relay_ip;
1010 if (ic_nameservers[0] == NONE)
1011 ic_nameservers[0] = ic_servaddr;
1012 ic_got_reply = IC_BOOTP;
1015 /* Show's over. Nothing to see here. */
1016 spin_unlock(&ic_recv_lock);
1019 /* Throw the packet out. */
1030 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1033 #ifdef IPCONFIG_DYNAMIC
1035 static int __init ic_dynamic(void)
1038 struct ic_device *d;
1039 unsigned long start_jiffies, timeout, jiff;
1040 int do_bootp = ic_proto_have_if & IC_BOOTP;
1041 int do_rarp = ic_proto_have_if & IC_RARP;
1044 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1045 * This routine gets only called when some pieces of information
1046 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1048 if (!ic_proto_enabled) {
1049 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1053 #ifdef IPCONFIG_BOOTP
1054 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1055 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1057 #ifdef IPCONFIG_RARP
1058 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1059 printk(KERN_ERR "RARP: No suitable device found.\n");
1062 if (!ic_proto_have_if)
1063 /* Error message already printed */
1069 #ifdef IPCONFIG_BOOTP
1073 #ifdef IPCONFIG_RARP
1079 * Send requests and wait, until we get an answer. This loop
1080 * seems to be a terrible waste of CPU time, but actually there is
1081 * only one process running at all, so we don't need to use any
1082 * scheduler functions.
1083 * [Actually we could now, but the nothing else running note still
1086 printk(KERN_NOTICE "Sending %s%s%s requests .",
1088 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1089 (do_bootp && do_rarp) ? " and " : "",
1090 do_rarp ? "RARP" : "");
1092 start_jiffies = jiffies;
1094 retries = CONF_SEND_RETRIES;
1095 get_random_bytes(&timeout, sizeof(timeout));
1096 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1098 #ifdef IPCONFIG_BOOTP
1099 if (do_bootp && (d->able & IC_BOOTP))
1100 ic_bootp_send_if(d, jiffies - start_jiffies);
1102 #ifdef IPCONFIG_RARP
1103 if (do_rarp && (d->able & IC_RARP))
1107 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1108 while (time_before(jiffies, jiff) && !ic_got_reply)
1109 schedule_timeout_uninterruptible(1);
1110 #ifdef IPCONFIG_DHCP
1111 /* DHCP isn't done until we get a DHCPACK. */
1112 if ((ic_got_reply & IC_BOOTP)
1113 && (ic_proto_enabled & IC_USE_DHCP)
1114 && ic_dhcp_msgtype != DHCPACK)
1120 #endif /* IPCONFIG_DHCP */
1131 printk(" timed out!\n");
1137 timeout = timeout CONF_TIMEOUT_MULT;
1138 if (timeout > CONF_TIMEOUT_MAX)
1139 timeout = CONF_TIMEOUT_MAX;
1144 #ifdef IPCONFIG_BOOTP
1148 #ifdef IPCONFIG_RARP
1153 if (!ic_got_reply) {
1158 printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1159 ((ic_got_reply & IC_RARP) ? "RARP"
1160 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1161 NIPQUAD(ic_servaddr));
1162 printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1167 #endif /* IPCONFIG_DYNAMIC */
1169 #ifdef CONFIG_PROC_FS
1171 static int pnp_seq_show(struct seq_file *seq, void *v)
1175 if (ic_proto_used & IC_PROTO)
1176 seq_printf(seq, "#PROTO: %s\n",
1177 (ic_proto_used & IC_RARP) ? "RARP"
1178 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1180 seq_puts(seq, "#MANUAL\n");
1184 "domain %s\n", ic_domain);
1185 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1186 if (ic_nameservers[i] != NONE)
1188 "nameserver %u.%u.%u.%u\n",
1189 NIPQUAD(ic_nameservers[i]));
1191 if (ic_servaddr != NONE)
1193 "bootserver %u.%u.%u.%u\n",
1194 NIPQUAD(ic_servaddr));
1198 static int pnp_seq_open(struct inode *indoe, struct file *file)
1200 return single_open(file, pnp_seq_show, NULL);
1203 static struct file_operations pnp_seq_fops = {
1204 .owner = THIS_MODULE,
1205 .open = pnp_seq_open,
1207 .llseek = seq_lseek,
1208 .release = single_release,
1210 #endif /* CONFIG_PROC_FS */
1213 * Extract IP address from the parameter string if needed. Note that we
1214 * need to have root_server_addr set _before_ IPConfig gets called as it
1217 __be32 __init root_nfs_parse_addr(char *name)
1224 while (octets < 4) {
1225 while (*cp >= '0' && *cp <= '9')
1227 if (cp == cq || cp - cq > 3)
1229 if (*cp == '.' || octets == 3)
1235 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1238 addr = in_aton(name);
1239 memmove(name, cp, strlen(cp) + 1);
1247 * IP Autoconfig dispatcher.
1250 static int __init ip_auto_config(void)
1254 #ifdef CONFIG_PROC_FS
1255 proc_net_fops_create("pnp", S_IRUGO, &pnp_seq_fops);
1256 #endif /* CONFIG_PROC_FS */
1261 DBG(("IP-Config: Entered.\n"));
1262 #ifdef IPCONFIG_DYNAMIC
1265 /* Give hardware a chance to settle */
1266 msleep(CONF_PRE_OPEN);
1268 /* Setup all network devices */
1269 if (ic_open_devs() < 0)
1272 /* Give drivers a chance to settle */
1273 ssleep(CONF_POST_OPEN);
1276 * If the config information is insufficient (e.g., our IP address or
1277 * IP address of the boot server is missing or we have multiple network
1278 * interfaces and no default was set), use BOOTP or RARP to get the
1281 if (ic_myaddr == NONE ||
1282 #ifdef CONFIG_ROOT_NFS
1283 (MAJOR(ROOT_DEV) == UNNAMED_MAJOR
1284 && root_server_addr == NONE
1285 && ic_servaddr == NONE) ||
1287 ic_first_dev->next) {
1288 #ifdef IPCONFIG_DYNAMIC
1290 int retries = CONF_OPEN_RETRIES;
1292 if (ic_dynamic() < 0) {
1296 * I don't know why, but sometimes the
1297 * eepro100 driver (at least) gets upset and
1298 * doesn't work the first time it's opened.
1299 * But then if you close it and reopen it, it
1300 * works just fine. So we need to try that at
1301 * least once before giving up.
1303 * Also, if the root will be NFS-mounted, we
1304 * have nowhere to go if DHCP fails. So we
1305 * just have to keep trying forever.
1309 #ifdef CONFIG_ROOT_NFS
1310 if (ROOT_DEV == Root_NFS) {
1312 "IP-Config: Retrying forever (NFS root)...\n");
1319 "IP-Config: Reopening network devices...\n");
1323 /* Oh, well. At least we tried. */
1324 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1327 #else /* !DYNAMIC */
1328 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1331 #endif /* IPCONFIG_DYNAMIC */
1333 /* Device selected manually or only one device -> use it */
1334 ic_dev = ic_first_dev->dev;
1337 addr = root_nfs_parse_addr(root_server_path);
1338 if (root_server_addr == NONE)
1339 root_server_addr = addr;
1342 * Use defaults whereever applicable.
1344 if (ic_defaults() < 0)
1348 * Close all network devices except the device we've
1349 * autoconfigured and set up routes.
1352 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1356 * Record which protocol was actually used.
1358 #ifdef IPCONFIG_DYNAMIC
1359 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1362 #ifndef IPCONFIG_SILENT
1364 * Clue in the operator.
1366 printk("IP-Config: Complete:");
1367 printk("\n device=%s", ic_dev->name);
1368 printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1369 printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1370 printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1371 printk(",\n host=%s, domain=%s, nis-domain=%s",
1372 utsname()->nodename, ic_domain, utsname()->domainname);
1373 printk(",\n bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1374 printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1375 printk(", rootpath=%s", root_server_path);
1377 #endif /* !SILENT */
1382 late_initcall(ip_auto_config);
1386 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1387 * command line parameter. It consists of option fields separated by colons in
1388 * the following order:
1390 * <client-ip>:<server-ip>:<gw-ip>:<netmask>:<host name>:<device>:<PROTO>
1392 * Any of the fields can be empty which means to use a default value:
1393 * <client-ip> - address given by BOOTP or RARP
1394 * <server-ip> - address of host returning BOOTP or RARP packet
1395 * <gw-ip> - none, or the address returned by BOOTP
1396 * <netmask> - automatically determined from <client-ip>, or the
1397 * one returned by BOOTP
1398 * <host name> - <client-ip> in ASCII notation, or the name returned
1400 * <device> - use all available devices
1402 * off|none - don't do autoconfig at all (DEFAULT)
1403 * on|any - use any configured protocol
1404 * dhcp|bootp|rarp - use only the specified protocol
1405 * both - use both BOOTP and RARP (not DHCP)
1407 static int __init ic_proto_name(char *name)
1409 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1412 #ifdef CONFIG_IP_PNP_DHCP
1413 else if (!strcmp(name, "dhcp")) {
1414 ic_proto_enabled &= ~IC_RARP;
1418 #ifdef CONFIG_IP_PNP_BOOTP
1419 else if (!strcmp(name, "bootp")) {
1420 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1424 #ifdef CONFIG_IP_PNP_RARP
1425 else if (!strcmp(name, "rarp")) {
1426 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1430 #ifdef IPCONFIG_DYNAMIC
1431 else if (!strcmp(name, "both")) {
1432 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1439 static int __init ip_auto_config_setup(char *addrs)
1444 ic_set_manually = 1;
1446 ic_enable = (*addrs &&
1447 (strcmp(addrs, "off") != 0) &&
1448 (strcmp(addrs, "none") != 0));
1452 if (ic_proto_name(addrs))
1455 /* Parse the whole string */
1458 if ((cp = strchr(ip, ':')))
1460 if (strlen(ip) > 0) {
1461 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1464 if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1468 if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1472 if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1476 if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1480 if ((dp = strchr(ip, '.'))) {
1482 strlcpy(utsname()->domainname, dp,
1483 sizeof(utsname()->domainname));
1485 strlcpy(utsname()->nodename, ip,
1486 sizeof(utsname()->nodename));
1487 ic_host_name_set = 1;
1490 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1504 static int __init nfsaddrs_config_setup(char *addrs)
1506 return ip_auto_config_setup(addrs);
1509 __setup("ip=", ip_auto_config_setup);
1510 __setup("nfsaddrs=", nfsaddrs_config_setup);