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 /* vendor class identifier */
144 static char vendor_class_identifier[253] __initdata;
146 /* Persistent data: */
148 static int ic_proto_used; /* Protocol used, if any */
149 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
150 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
156 /* Name of user-selected boot device */
157 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
159 /* Protocols supported by available interfaces */
160 static int ic_proto_have_if __initdata = 0;
162 #ifdef IPCONFIG_DYNAMIC
163 static DEFINE_SPINLOCK(ic_recv_lock);
164 static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
167 static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
176 struct ic_device *next;
177 struct net_device *dev;
178 unsigned short flags;
183 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
184 static struct net_device *ic_dev __initdata = NULL; /* Selected device */
186 static int __init ic_open_devs(void)
188 struct ic_device *d, **last;
189 struct net_device *dev;
190 unsigned short oflags;
192 last = &ic_first_dev;
195 /* bring loopback device up first */
196 for_each_netdev(&init_net, dev) {
197 if (!(dev->flags & IFF_LOOPBACK))
199 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
200 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
203 for_each_netdev(&init_net, dev) {
204 if (dev->flags & IFF_LOOPBACK)
206 if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
207 (!(dev->flags & IFF_LOOPBACK) &&
208 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
209 strncmp(dev->name, "dummy", 5))) {
214 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
215 if (!(dev->flags & IFF_NOARP))
217 able &= ic_proto_enabled;
218 if (ic_proto_enabled && !able)
221 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
222 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
225 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
235 get_random_bytes(&d->xid, sizeof(__be32));
238 ic_proto_have_if |= able;
239 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
240 dev->name, able, d->xid));
248 if (user_dev_name[0])
249 printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
251 printk(KERN_ERR "IP-Config: No network devices available.\n");
257 static void __init ic_close_devs(void)
259 struct ic_device *d, *next;
260 struct net_device *dev;
268 DBG(("IP-Config: Downing %s\n", dev->name));
269 dev_change_flags(dev, d->flags);
277 * Interface to various network functions.
281 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
283 sin->sin_family = AF_INET;
284 sin->sin_addr.s_addr = addr;
285 sin->sin_port = port;
288 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
292 mm_segment_t oldfs = get_fs();
294 res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
299 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
303 mm_segment_t oldfs = get_fs();
305 res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
311 * Set up interface addresses and routes.
314 static int __init ic_setup_if(void)
317 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
320 memset(&ir, 0, sizeof(ir));
321 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
322 set_sockaddr(sin, ic_myaddr, 0);
323 if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
324 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
327 set_sockaddr(sin, ic_netmask, 0);
328 if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
329 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
332 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
333 if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
334 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
340 static int __init ic_setup_routes(void)
342 /* No need to setup device routes, only the default route... */
344 if (ic_gateway != NONE) {
348 memset(&rm, 0, sizeof(rm));
349 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
350 printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
353 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
354 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
355 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
356 rm.rt_flags = RTF_UP | RTF_GATEWAY;
357 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
358 printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
367 * Fill in default values for all missing parameters.
370 static int __init ic_defaults(void)
373 * At this point we have no userspace running so need not
374 * claim locks on system_utsname
377 if (!ic_host_name_set)
378 sprintf(init_utsname()->nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
380 if (root_server_addr == NONE)
381 root_server_addr = ic_servaddr;
383 if (ic_netmask == NONE) {
384 if (IN_CLASSA(ntohl(ic_myaddr)))
385 ic_netmask = htonl(IN_CLASSA_NET);
386 else if (IN_CLASSB(ntohl(ic_myaddr)))
387 ic_netmask = htonl(IN_CLASSB_NET);
388 else if (IN_CLASSC(ntohl(ic_myaddr)))
389 ic_netmask = htonl(IN_CLASSC_NET);
391 printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
395 printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
407 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
409 static struct packet_type rarp_packet_type __initdata = {
410 .type = __constant_htons(ETH_P_RARP),
411 .func = ic_rarp_recv,
414 static inline void ic_rarp_init(void)
416 dev_add_pack(&rarp_packet_type);
419 static inline void ic_rarp_cleanup(void)
421 dev_remove_pack(&rarp_packet_type);
425 * Process received RARP packet.
428 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
431 unsigned char *rarp_ptr;
433 unsigned char *sha, *tha; /* s for "source", t for "target" */
436 if (dev->nd_net != &init_net)
439 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
442 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
445 /* Basic sanity checks can be done without the lock. */
446 rarp = (struct arphdr *)skb_transport_header(skb);
448 /* If this test doesn't pass, it's not IP, or we should
451 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
454 /* If it's not a RARP reply, delete it. */
455 if (rarp->ar_op != htons(ARPOP_RREPLY))
458 /* If it's not Ethernet, delete it. */
459 if (rarp->ar_pro != htons(ETH_P_IP))
462 if (!pskb_may_pull(skb, arp_hdr_len(dev)))
465 /* OK, it is all there and looks valid, process... */
466 rarp = (struct arphdr *)skb_transport_header(skb);
467 rarp_ptr = (unsigned char *) (rarp + 1);
469 /* One reply at a time, please. */
470 spin_lock(&ic_recv_lock);
472 /* If we already have a reply, just drop the packet */
476 /* Find the ic_device that the packet arrived on */
478 while (d && d->dev != dev)
481 goto drop_unlock; /* should never happen */
483 /* Extract variable-width fields */
485 rarp_ptr += dev->addr_len;
486 memcpy(&sip, rarp_ptr, 4);
489 rarp_ptr += dev->addr_len;
490 memcpy(&tip, rarp_ptr, 4);
492 /* Discard packets which are not meant for us. */
493 if (memcmp(tha, dev->dev_addr, dev->addr_len))
496 /* Discard packets which are not from specified server. */
497 if (ic_servaddr != NONE && ic_servaddr != sip)
500 /* We have a winner! */
502 if (ic_myaddr == NONE)
505 ic_got_reply = IC_RARP;
508 /* Show's over. Nothing to see here. */
509 spin_unlock(&ic_recv_lock);
512 /* Throw the packet out. */
519 * Send RARP request packet over a single interface.
521 static void __init ic_rarp_send_if(struct ic_device *d)
523 struct net_device *dev = d->dev;
524 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
525 dev->dev_addr, dev->dev_addr);
530 * DHCP/BOOTP support.
533 #ifdef IPCONFIG_BOOTP
535 struct bootp_pkt { /* BOOTP packet format */
536 struct iphdr iph; /* IP header */
537 struct udphdr udph; /* UDP header */
538 u8 op; /* 1=request, 2=reply */
539 u8 htype; /* HW address type */
540 u8 hlen; /* HW address length */
541 u8 hops; /* Used only by gateways */
542 __be32 xid; /* Transaction ID */
543 __be16 secs; /* Seconds since we started */
544 __be16 flags; /* Just what it says */
545 __be32 client_ip; /* Client's IP address if known */
546 __be32 your_ip; /* Assigned IP address */
547 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
548 __be32 relay_ip; /* IP address of BOOTP relay */
549 u8 hw_addr[16]; /* Client's HW address */
550 u8 serv_name[64]; /* Server host name */
551 u8 boot_file[128]; /* Name of boot file */
552 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
556 #define BOOTP_REQUEST 1
557 #define BOOTP_REPLY 2
559 /* DHCP message types */
560 #define DHCPDISCOVER 1
562 #define DHCPREQUEST 3
563 #define DHCPDECLINE 4
566 #define DHCPRELEASE 7
569 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
571 static struct packet_type bootp_packet_type __initdata = {
572 .type = __constant_htons(ETH_P_IP),
573 .func = ic_bootp_recv,
578 * Initialize DHCP/BOOTP extension fields in the request.
581 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
586 ic_dhcp_init_options(u8 *options)
588 u8 mt = ((ic_servaddr == NONE)
589 ? DHCPDISCOVER : DHCPREQUEST);
593 #ifdef IPCONFIG_DEBUG
594 printk("DHCP: Sending message type %d\n", mt);
597 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
600 *e++ = 53; /* DHCP message type */
604 if (mt == DHCPREQUEST) {
605 *e++ = 54; /* Server ID (IP address) */
607 memcpy(e, &ic_servaddr, 4);
610 *e++ = 50; /* Requested IP address */
612 memcpy(e, &ic_myaddr, 4);
618 static const u8 ic_req_params[] = {
620 3, /* Default gateway */
623 15, /* Domain name */
625 40, /* NIS domain name */
628 *e++ = 55; /* Parameter request list */
629 *e++ = sizeof(ic_req_params);
630 memcpy(e, ic_req_params, sizeof(ic_req_params));
631 e += sizeof(ic_req_params);
633 if (*vendor_class_identifier) {
634 printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
635 vendor_class_identifier);
636 *e++ = 60; /* Class-identifier */
637 len = strlen(vendor_class_identifier);
639 memcpy(e, vendor_class_identifier, len);
644 *e++ = 255; /* End of the list */
647 #endif /* IPCONFIG_DHCP */
649 static void __init ic_bootp_init_ext(u8 *e)
651 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
653 *e++ = 1; /* Subnet mask request */
656 *e++ = 3; /* Default gateway request */
659 *e++ = 5; /* Name server request */
662 *e++ = 12; /* Host name request */
665 *e++ = 40; /* NIS Domain name request */
668 *e++ = 17; /* Boot path */
672 *e++ = 57; /* set extension buffer size for reply */
674 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
677 *e++ = 255; /* End of the list */
682 * Initialize the DHCP/BOOTP mechanism.
684 static inline void ic_bootp_init(void)
688 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
689 ic_nameservers[i] = NONE;
691 dev_add_pack(&bootp_packet_type);
696 * DHCP/BOOTP cleanup.
698 static inline void ic_bootp_cleanup(void)
700 dev_remove_pack(&bootp_packet_type);
705 * Send DHCP/BOOTP request to single interface.
707 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
709 struct net_device *dev = d->dev;
712 int hh_len = LL_RESERVED_SPACE(dev);
715 /* Allocate packet */
716 skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
719 skb_reserve(skb, hh_len);
720 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
721 memset(b, 0, sizeof(struct bootp_pkt));
723 /* Construct IP header */
724 skb_reset_network_header(skb);
728 h->tot_len = htons(sizeof(struct bootp_pkt));
729 h->frag_off = htons(IP_DF);
731 h->protocol = IPPROTO_UDP;
732 h->daddr = htonl(INADDR_BROADCAST);
733 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
735 /* Construct UDP header */
736 b->udph.source = htons(68);
737 b->udph.dest = htons(67);
738 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
739 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
741 /* Construct DHCP/BOOTP header */
742 b->op = BOOTP_REQUEST;
743 if (dev->type < 256) /* check for false types */
744 b->htype = dev->type;
745 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
746 b->htype = ARPHRD_IEEE802;
747 else if (dev->type == ARPHRD_FDDI)
748 b->htype = ARPHRD_ETHER;
750 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
751 b->htype = dev->type; /* can cause undefined behavior */
753 b->hlen = dev->addr_len;
756 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
757 b->secs = htons(jiffies_diff / HZ);
760 /* add DHCP options or BOOTP extensions */
762 if (ic_proto_enabled & IC_USE_DHCP)
763 ic_dhcp_init_options(b->exten);
766 ic_bootp_init_ext(b->exten);
768 /* Chain packet down the line... */
770 skb->protocol = htons(ETH_P_IP);
771 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
772 dev->broadcast, dev->dev_addr, skb->len) < 0 ||
773 dev_queue_xmit(skb) < 0)
779 * Copy BOOTP-supplied string if not already set.
781 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
787 memcpy(dest, src, len);
794 * Process BOOTP extensions.
796 static void __init ic_do_bootp_ext(u8 *ext)
801 #ifdef IPCONFIG_DEBUG
804 printk("DHCP/BOOTP: Got extension %d:",*ext);
805 for (c=ext+2; c<ext+2+ext[1]; c++)
811 case 1: /* Subnet mask */
812 if (ic_netmask == NONE)
813 memcpy(&ic_netmask, ext+1, 4);
815 case 3: /* Default gateway */
816 if (ic_gateway == NONE)
817 memcpy(&ic_gateway, ext+1, 4);
819 case 6: /* DNS server */
821 if (servers > CONF_NAMESERVERS_MAX)
822 servers = CONF_NAMESERVERS_MAX;
823 for (i = 0; i < servers; i++) {
824 if (ic_nameservers[i] == NONE)
825 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
828 case 12: /* Host name */
829 ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
830 ic_host_name_set = 1;
832 case 15: /* Domain name (DNS) */
833 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
835 case 17: /* Root path */
836 if (!root_server_path[0])
837 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
839 case 40: /* NIS Domain name (_not_ DNS) */
840 ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
847 * Receive BOOTP reply.
849 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
856 if (dev->nd_net != &init_net)
859 /* Perform verifications before taking the lock. */
860 if (skb->pkt_type == PACKET_OTHERHOST)
863 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
866 if (!pskb_may_pull(skb,
867 sizeof(struct iphdr) +
868 sizeof(struct udphdr)))
871 b = (struct bootp_pkt *)skb_network_header(skb);
874 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
877 /* Fragments are not supported */
878 if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
880 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
885 if (skb->len < ntohs(h->tot_len))
888 if (ip_fast_csum((char *) h, h->ihl))
891 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
894 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
897 len = ntohs(b->udph.len) - sizeof(struct udphdr);
898 ext_len = len - (sizeof(*b) -
899 sizeof(struct iphdr) -
900 sizeof(struct udphdr) -
905 /* Ok the front looks good, make sure we can get at the rest. */
906 if (!pskb_may_pull(skb, skb->len))
909 b = (struct bootp_pkt *)skb_network_header(skb);
912 /* One reply at a time, please. */
913 spin_lock(&ic_recv_lock);
915 /* If we already have a reply, just drop the packet */
919 /* Find the ic_device that the packet arrived on */
921 while (d && d->dev != dev)
924 goto drop_unlock; /* should never happen */
926 /* Is it a reply to our BOOTP request? */
927 if (b->op != BOOTP_REPLY ||
930 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
936 /* Parse extensions */
938 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
939 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
943 if (ic_proto_enabled & IC_USE_DHCP) {
944 __be32 server_id = NONE;
948 while (ext < end && *ext != 0xff) {
950 if (*opt == 0) /* Padding */
956 case 53: /* Message type */
960 case 54: /* Server ID (IP address) */
962 memcpy(&server_id, opt + 2, 4);
967 #ifdef IPCONFIG_DEBUG
968 printk("DHCP: Got message type %d\n", mt);
973 /* While in the process of accepting one offer,
976 if (ic_myaddr != NONE)
979 /* Let's accept that offer. */
980 ic_myaddr = b->your_ip;
981 ic_servaddr = server_id;
982 #ifdef IPCONFIG_DEBUG
983 printk("DHCP: Offered address %u.%u.%u.%u",
985 printk(" by server %u.%u.%u.%u\n",
986 NIPQUAD(ic_servaddr));
988 /* The DHCP indicated server address takes
989 * precedence over the bootp header one if
990 * they are different.
992 if ((server_id != NONE) &&
993 (b->server_ip != server_id))
994 b->server_ip = ic_servaddr;
998 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1005 /* Urque. Forget it*/
1011 ic_dhcp_msgtype = mt;
1014 #endif /* IPCONFIG_DHCP */
1017 while (ext < end && *ext != 0xff) {
1019 if (*opt == 0) /* Padding */
1023 ic_do_bootp_ext(opt);
1027 /* We have a winner! */
1029 ic_myaddr = b->your_ip;
1030 ic_servaddr = b->server_ip;
1031 if (ic_gateway == NONE && b->relay_ip)
1032 ic_gateway = b->relay_ip;
1033 if (ic_nameservers[0] == NONE)
1034 ic_nameservers[0] = ic_servaddr;
1035 ic_got_reply = IC_BOOTP;
1038 /* Show's over. Nothing to see here. */
1039 spin_unlock(&ic_recv_lock);
1042 /* Throw the packet out. */
1053 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1056 #ifdef IPCONFIG_DYNAMIC
1058 static int __init ic_dynamic(void)
1061 struct ic_device *d;
1062 unsigned long start_jiffies, timeout, jiff;
1063 int do_bootp = ic_proto_have_if & IC_BOOTP;
1064 int do_rarp = ic_proto_have_if & IC_RARP;
1067 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1068 * This routine gets only called when some pieces of information
1069 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1071 if (!ic_proto_enabled) {
1072 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1076 #ifdef IPCONFIG_BOOTP
1077 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1078 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1080 #ifdef IPCONFIG_RARP
1081 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1082 printk(KERN_ERR "RARP: No suitable device found.\n");
1085 if (!ic_proto_have_if)
1086 /* Error message already printed */
1092 #ifdef IPCONFIG_BOOTP
1096 #ifdef IPCONFIG_RARP
1102 * Send requests and wait, until we get an answer. This loop
1103 * seems to be a terrible waste of CPU time, but actually there is
1104 * only one process running at all, so we don't need to use any
1105 * scheduler functions.
1106 * [Actually we could now, but the nothing else running note still
1109 printk(KERN_NOTICE "Sending %s%s%s requests .",
1111 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1112 (do_bootp && do_rarp) ? " and " : "",
1113 do_rarp ? "RARP" : "");
1115 start_jiffies = jiffies;
1117 retries = CONF_SEND_RETRIES;
1118 get_random_bytes(&timeout, sizeof(timeout));
1119 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1121 #ifdef IPCONFIG_BOOTP
1122 if (do_bootp && (d->able & IC_BOOTP))
1123 ic_bootp_send_if(d, jiffies - start_jiffies);
1125 #ifdef IPCONFIG_RARP
1126 if (do_rarp && (d->able & IC_RARP))
1130 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1131 while (time_before(jiffies, jiff) && !ic_got_reply)
1132 schedule_timeout_uninterruptible(1);
1133 #ifdef IPCONFIG_DHCP
1134 /* DHCP isn't done until we get a DHCPACK. */
1135 if ((ic_got_reply & IC_BOOTP)
1136 && (ic_proto_enabled & IC_USE_DHCP)
1137 && ic_dhcp_msgtype != DHCPACK)
1143 #endif /* IPCONFIG_DHCP */
1154 printk(" timed out!\n");
1160 timeout = timeout CONF_TIMEOUT_MULT;
1161 if (timeout > CONF_TIMEOUT_MAX)
1162 timeout = CONF_TIMEOUT_MAX;
1167 #ifdef IPCONFIG_BOOTP
1171 #ifdef IPCONFIG_RARP
1176 if (!ic_got_reply) {
1181 printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1182 ((ic_got_reply & IC_RARP) ? "RARP"
1183 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1184 NIPQUAD(ic_servaddr));
1185 printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1190 #endif /* IPCONFIG_DYNAMIC */
1192 #ifdef CONFIG_PROC_FS
1194 static int pnp_seq_show(struct seq_file *seq, void *v)
1198 if (ic_proto_used & IC_PROTO)
1199 seq_printf(seq, "#PROTO: %s\n",
1200 (ic_proto_used & IC_RARP) ? "RARP"
1201 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1203 seq_puts(seq, "#MANUAL\n");
1207 "domain %s\n", ic_domain);
1208 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1209 if (ic_nameservers[i] != NONE)
1211 "nameserver %u.%u.%u.%u\n",
1212 NIPQUAD(ic_nameservers[i]));
1214 if (ic_servaddr != NONE)
1216 "bootserver %u.%u.%u.%u\n",
1217 NIPQUAD(ic_servaddr));
1221 static int pnp_seq_open(struct inode *indoe, struct file *file)
1223 return single_open(file, pnp_seq_show, NULL);
1226 static const struct file_operations pnp_seq_fops = {
1227 .owner = THIS_MODULE,
1228 .open = pnp_seq_open,
1230 .llseek = seq_lseek,
1231 .release = single_release,
1233 #endif /* CONFIG_PROC_FS */
1236 * Extract IP address from the parameter string if needed. Note that we
1237 * need to have root_server_addr set _before_ IPConfig gets called as it
1240 __be32 __init root_nfs_parse_addr(char *name)
1247 while (octets < 4) {
1248 while (*cp >= '0' && *cp <= '9')
1250 if (cp == cq || cp - cq > 3)
1252 if (*cp == '.' || octets == 3)
1258 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1261 addr = in_aton(name);
1262 memmove(name, cp, strlen(cp) + 1);
1270 * IP Autoconfig dispatcher.
1273 static int __init ip_auto_config(void)
1277 #ifdef CONFIG_PROC_FS
1278 proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1279 #endif /* CONFIG_PROC_FS */
1284 DBG(("IP-Config: Entered.\n"));
1285 #ifdef IPCONFIG_DYNAMIC
1288 /* Give hardware a chance to settle */
1289 msleep(CONF_PRE_OPEN);
1291 /* Setup all network devices */
1292 if (ic_open_devs() < 0)
1295 /* Give drivers a chance to settle */
1296 ssleep(CONF_POST_OPEN);
1299 * If the config information is insufficient (e.g., our IP address or
1300 * IP address of the boot server is missing or we have multiple network
1301 * interfaces and no default was set), use BOOTP or RARP to get the
1304 if (ic_myaddr == NONE ||
1305 #ifdef CONFIG_ROOT_NFS
1306 (root_server_addr == NONE
1307 && ic_servaddr == NONE
1308 && ROOT_DEV == Root_NFS) ||
1310 ic_first_dev->next) {
1311 #ifdef IPCONFIG_DYNAMIC
1313 int retries = CONF_OPEN_RETRIES;
1315 if (ic_dynamic() < 0) {
1319 * I don't know why, but sometimes the
1320 * eepro100 driver (at least) gets upset and
1321 * doesn't work the first time it's opened.
1322 * But then if you close it and reopen it, it
1323 * works just fine. So we need to try that at
1324 * least once before giving up.
1326 * Also, if the root will be NFS-mounted, we
1327 * have nowhere to go if DHCP fails. So we
1328 * just have to keep trying forever.
1332 #ifdef CONFIG_ROOT_NFS
1333 if (ROOT_DEV == Root_NFS) {
1335 "IP-Config: Retrying forever (NFS root)...\n");
1342 "IP-Config: Reopening network devices...\n");
1346 /* Oh, well. At least we tried. */
1347 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1350 #else /* !DYNAMIC */
1351 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1354 #endif /* IPCONFIG_DYNAMIC */
1356 /* Device selected manually or only one device -> use it */
1357 ic_dev = ic_first_dev->dev;
1360 addr = root_nfs_parse_addr(root_server_path);
1361 if (root_server_addr == NONE)
1362 root_server_addr = addr;
1365 * Use defaults whereever applicable.
1367 if (ic_defaults() < 0)
1371 * Close all network devices except the device we've
1372 * autoconfigured and set up routes.
1375 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1379 * Record which protocol was actually used.
1381 #ifdef IPCONFIG_DYNAMIC
1382 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1385 #ifndef IPCONFIG_SILENT
1387 * Clue in the operator.
1389 printk("IP-Config: Complete:");
1390 printk("\n device=%s", ic_dev->name);
1391 printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1392 printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1393 printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1394 printk(",\n host=%s, domain=%s, nis-domain=%s",
1395 utsname()->nodename, ic_domain, utsname()->domainname);
1396 printk(",\n bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1397 printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1398 printk(", rootpath=%s", root_server_path);
1400 #endif /* !SILENT */
1405 late_initcall(ip_auto_config);
1409 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1410 * command line parameter. See Documentation/nfsroot.txt.
1412 static int __init ic_proto_name(char *name)
1414 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1417 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1420 #ifdef CONFIG_IP_PNP_DHCP
1421 else if (!strcmp(name, "dhcp")) {
1422 ic_proto_enabled &= ~IC_RARP;
1426 #ifdef CONFIG_IP_PNP_BOOTP
1427 else if (!strcmp(name, "bootp")) {
1428 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1432 #ifdef CONFIG_IP_PNP_RARP
1433 else if (!strcmp(name, "rarp")) {
1434 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1438 #ifdef IPCONFIG_DYNAMIC
1439 else if (!strcmp(name, "both")) {
1440 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1447 static int __init ip_auto_config_setup(char *addrs)
1452 ic_set_manually = 1;
1456 * If any dhcp, bootp etc options are set, leave autoconfig on
1457 * and skip the below static IP processing.
1459 if (ic_proto_name(addrs))
1462 /* If no static IP is given, turn off autoconfig and bail. */
1464 strcmp(addrs, "off") == 0 ||
1465 strcmp(addrs, "none") == 0) {
1470 /* Parse string for static IP assignment. */
1473 if ((cp = strchr(ip, ':')))
1475 if (strlen(ip) > 0) {
1476 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1479 if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1483 if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1487 if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1491 if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1495 if ((dp = strchr(ip, '.'))) {
1497 strlcpy(utsname()->domainname, dp,
1498 sizeof(utsname()->domainname));
1500 strlcpy(utsname()->nodename, ip,
1501 sizeof(utsname()->nodename));
1502 ic_host_name_set = 1;
1505 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1508 if (ic_proto_name(ip) == 0 &&
1509 ic_myaddr == NONE) {
1522 static int __init nfsaddrs_config_setup(char *addrs)
1524 return ip_auto_config_setup(addrs);
1527 static int __init vendor_class_identifier_setup(char *addrs)
1529 if (strlcpy(vendor_class_identifier, addrs,
1530 sizeof(vendor_class_identifier))
1531 >= sizeof(vendor_class_identifier))
1532 printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1533 vendor_class_identifier);
1537 __setup("ip=", ip_auto_config_setup);
1538 __setup("nfsaddrs=", nfsaddrs_config_setup);
1539 __setup("dhcpclass=", vendor_class_identifier_setup);