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(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,
463 sizeof(struct arphdr) +
464 (2 * dev->addr_len) +
468 /* OK, it is all there and looks valid, process... */
469 rarp = (struct arphdr *)skb_transport_header(skb);
470 rarp_ptr = (unsigned char *) (rarp + 1);
472 /* One reply at a time, please. */
473 spin_lock(&ic_recv_lock);
475 /* If we already have a reply, just drop the packet */
479 /* Find the ic_device that the packet arrived on */
481 while (d && d->dev != dev)
484 goto drop_unlock; /* should never happen */
486 /* Extract variable-width fields */
488 rarp_ptr += dev->addr_len;
489 memcpy(&sip, rarp_ptr, 4);
492 rarp_ptr += dev->addr_len;
493 memcpy(&tip, rarp_ptr, 4);
495 /* Discard packets which are not meant for us. */
496 if (memcmp(tha, dev->dev_addr, dev->addr_len))
499 /* Discard packets which are not from specified server. */
500 if (ic_servaddr != NONE && ic_servaddr != sip)
503 /* We have a winner! */
505 if (ic_myaddr == NONE)
508 ic_got_reply = IC_RARP;
511 /* Show's over. Nothing to see here. */
512 spin_unlock(&ic_recv_lock);
515 /* Throw the packet out. */
522 * Send RARP request packet over a single interface.
524 static void __init ic_rarp_send_if(struct ic_device *d)
526 struct net_device *dev = d->dev;
527 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
528 dev->dev_addr, dev->dev_addr);
533 * DHCP/BOOTP support.
536 #ifdef IPCONFIG_BOOTP
538 struct bootp_pkt { /* BOOTP packet format */
539 struct iphdr iph; /* IP header */
540 struct udphdr udph; /* UDP header */
541 u8 op; /* 1=request, 2=reply */
542 u8 htype; /* HW address type */
543 u8 hlen; /* HW address length */
544 u8 hops; /* Used only by gateways */
545 __be32 xid; /* Transaction ID */
546 __be16 secs; /* Seconds since we started */
547 __be16 flags; /* Just what it says */
548 __be32 client_ip; /* Client's IP address if known */
549 __be32 your_ip; /* Assigned IP address */
550 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
551 __be32 relay_ip; /* IP address of BOOTP relay */
552 u8 hw_addr[16]; /* Client's HW address */
553 u8 serv_name[64]; /* Server host name */
554 u8 boot_file[128]; /* Name of boot file */
555 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
559 #define BOOTP_REQUEST 1
560 #define BOOTP_REPLY 2
562 /* DHCP message types */
563 #define DHCPDISCOVER 1
565 #define DHCPREQUEST 3
566 #define DHCPDECLINE 4
569 #define DHCPRELEASE 7
572 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
574 static struct packet_type bootp_packet_type __initdata = {
575 .type = __constant_htons(ETH_P_IP),
576 .func = ic_bootp_recv,
581 * Initialize DHCP/BOOTP extension fields in the request.
584 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
589 ic_dhcp_init_options(u8 *options)
591 u8 mt = ((ic_servaddr == NONE)
592 ? DHCPDISCOVER : DHCPREQUEST);
596 #ifdef IPCONFIG_DEBUG
597 printk("DHCP: Sending message type %d\n", mt);
600 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
603 *e++ = 53; /* DHCP message type */
607 if (mt == DHCPREQUEST) {
608 *e++ = 54; /* Server ID (IP address) */
610 memcpy(e, &ic_servaddr, 4);
613 *e++ = 50; /* Requested IP address */
615 memcpy(e, &ic_myaddr, 4);
621 static const u8 ic_req_params[] = {
623 3, /* Default gateway */
626 15, /* Domain name */
628 40, /* NIS domain name */
631 *e++ = 55; /* Parameter request list */
632 *e++ = sizeof(ic_req_params);
633 memcpy(e, ic_req_params, sizeof(ic_req_params));
634 e += sizeof(ic_req_params);
636 if (*vendor_class_identifier) {
637 printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
638 vendor_class_identifier);
639 *e++ = 60; /* Class-identifier */
640 len = strlen(vendor_class_identifier);
642 memcpy(e, vendor_class_identifier, len);
647 *e++ = 255; /* End of the list */
650 #endif /* IPCONFIG_DHCP */
652 static void __init ic_bootp_init_ext(u8 *e)
654 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
656 *e++ = 1; /* Subnet mask request */
659 *e++ = 3; /* Default gateway request */
662 *e++ = 5; /* Name server request */
665 *e++ = 12; /* Host name request */
668 *e++ = 40; /* NIS Domain name request */
671 *e++ = 17; /* Boot path */
675 *e++ = 57; /* set extension buffer size for reply */
677 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
680 *e++ = 255; /* End of the list */
685 * Initialize the DHCP/BOOTP mechanism.
687 static inline void ic_bootp_init(void)
691 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
692 ic_nameservers[i] = NONE;
694 dev_add_pack(&bootp_packet_type);
699 * DHCP/BOOTP cleanup.
701 static inline void ic_bootp_cleanup(void)
703 dev_remove_pack(&bootp_packet_type);
708 * Send DHCP/BOOTP request to single interface.
710 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
712 struct net_device *dev = d->dev;
715 int hh_len = LL_RESERVED_SPACE(dev);
718 /* Allocate packet */
719 skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
722 skb_reserve(skb, hh_len);
723 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
724 memset(b, 0, sizeof(struct bootp_pkt));
726 /* Construct IP header */
727 skb_reset_network_header(skb);
731 h->tot_len = htons(sizeof(struct bootp_pkt));
732 h->frag_off = htons(IP_DF);
734 h->protocol = IPPROTO_UDP;
735 h->daddr = htonl(INADDR_BROADCAST);
736 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
738 /* Construct UDP header */
739 b->udph.source = htons(68);
740 b->udph.dest = htons(67);
741 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
742 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
744 /* Construct DHCP/BOOTP header */
745 b->op = BOOTP_REQUEST;
746 if (dev->type < 256) /* check for false types */
747 b->htype = dev->type;
748 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
749 b->htype = ARPHRD_IEEE802;
750 else if (dev->type == ARPHRD_FDDI)
751 b->htype = ARPHRD_ETHER;
753 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
754 b->htype = dev->type; /* can cause undefined behavior */
757 /* server_ip and your_ip address are both already zero per RFC2131 */
758 b->hlen = dev->addr_len;
759 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
760 b->secs = htons(jiffies_diff / HZ);
763 /* add DHCP options or BOOTP extensions */
765 if (ic_proto_enabled & IC_USE_DHCP)
766 ic_dhcp_init_options(b->exten);
769 ic_bootp_init_ext(b->exten);
771 /* Chain packet down the line... */
773 skb->protocol = htons(ETH_P_IP);
774 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
775 dev->broadcast, dev->dev_addr, skb->len) < 0 ||
776 dev_queue_xmit(skb) < 0)
782 * Copy BOOTP-supplied string if not already set.
784 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
790 memcpy(dest, src, len);
797 * Process BOOTP extensions.
799 static void __init ic_do_bootp_ext(u8 *ext)
804 #ifdef IPCONFIG_DEBUG
807 printk("DHCP/BOOTP: Got extension %d:",*ext);
808 for (c=ext+2; c<ext+2+ext[1]; c++)
814 case 1: /* Subnet mask */
815 if (ic_netmask == NONE)
816 memcpy(&ic_netmask, ext+1, 4);
818 case 3: /* Default gateway */
819 if (ic_gateway == NONE)
820 memcpy(&ic_gateway, ext+1, 4);
822 case 6: /* DNS server */
824 if (servers > CONF_NAMESERVERS_MAX)
825 servers = CONF_NAMESERVERS_MAX;
826 for (i = 0; i < servers; i++) {
827 if (ic_nameservers[i] == NONE)
828 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
831 case 12: /* Host name */
832 ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
833 ic_host_name_set = 1;
835 case 15: /* Domain name (DNS) */
836 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
838 case 17: /* Root path */
839 if (!root_server_path[0])
840 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
842 case 40: /* NIS Domain name (_not_ DNS) */
843 ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
850 * Receive BOOTP reply.
852 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
859 if (dev->nd_net != &init_net)
862 /* Perform verifications before taking the lock. */
863 if (skb->pkt_type == PACKET_OTHERHOST)
866 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
869 if (!pskb_may_pull(skb,
870 sizeof(struct iphdr) +
871 sizeof(struct udphdr)))
874 b = (struct bootp_pkt *)skb_network_header(skb);
877 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
880 /* Fragments are not supported */
881 if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
883 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
888 if (skb->len < ntohs(h->tot_len))
891 if (ip_fast_csum((char *) h, h->ihl))
894 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
897 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
900 len = ntohs(b->udph.len) - sizeof(struct udphdr);
901 ext_len = len - (sizeof(*b) -
902 sizeof(struct iphdr) -
903 sizeof(struct udphdr) -
908 /* Ok the front looks good, make sure we can get at the rest. */
909 if (!pskb_may_pull(skb, skb->len))
912 b = (struct bootp_pkt *)skb_network_header(skb);
915 /* One reply at a time, please. */
916 spin_lock(&ic_recv_lock);
918 /* If we already have a reply, just drop the packet */
922 /* Find the ic_device that the packet arrived on */
924 while (d && d->dev != dev)
927 goto drop_unlock; /* should never happen */
929 /* Is it a reply to our BOOTP request? */
930 if (b->op != BOOTP_REPLY ||
933 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
939 /* Parse extensions */
941 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
942 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
946 if (ic_proto_enabled & IC_USE_DHCP) {
947 __be32 server_id = NONE;
951 while (ext < end && *ext != 0xff) {
953 if (*opt == 0) /* Padding */
959 case 53: /* Message type */
963 case 54: /* Server ID (IP address) */
965 memcpy(&server_id, opt + 2, 4);
970 #ifdef IPCONFIG_DEBUG
971 printk("DHCP: Got message type %d\n", mt);
976 /* While in the process of accepting one offer,
979 if (ic_myaddr != NONE)
982 /* Let's accept that offer. */
983 ic_myaddr = b->your_ip;
984 ic_servaddr = server_id;
985 #ifdef IPCONFIG_DEBUG
986 printk("DHCP: Offered address %u.%u.%u.%u",
988 printk(" by server %u.%u.%u.%u\n",
989 NIPQUAD(ic_servaddr));
991 /* The DHCP indicated server address takes
992 * precedence over the bootp header one if
993 * they are different.
995 if ((server_id != NONE) &&
996 (b->server_ip != server_id))
997 b->server_ip = ic_servaddr;
1001 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1008 /* Urque. Forget it*/
1014 ic_dhcp_msgtype = mt;
1017 #endif /* IPCONFIG_DHCP */
1020 while (ext < end && *ext != 0xff) {
1022 if (*opt == 0) /* Padding */
1026 ic_do_bootp_ext(opt);
1030 /* We have a winner! */
1032 ic_myaddr = b->your_ip;
1033 ic_servaddr = b->server_ip;
1034 if (ic_gateway == NONE && b->relay_ip)
1035 ic_gateway = b->relay_ip;
1036 if (ic_nameservers[0] == NONE)
1037 ic_nameservers[0] = ic_servaddr;
1038 ic_got_reply = IC_BOOTP;
1041 /* Show's over. Nothing to see here. */
1042 spin_unlock(&ic_recv_lock);
1045 /* Throw the packet out. */
1056 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1059 #ifdef IPCONFIG_DYNAMIC
1061 static int __init ic_dynamic(void)
1064 struct ic_device *d;
1065 unsigned long start_jiffies, timeout, jiff;
1066 int do_bootp = ic_proto_have_if & IC_BOOTP;
1067 int do_rarp = ic_proto_have_if & IC_RARP;
1070 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1071 * This routine gets only called when some pieces of information
1072 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1074 if (!ic_proto_enabled) {
1075 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1079 #ifdef IPCONFIG_BOOTP
1080 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1081 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1083 #ifdef IPCONFIG_RARP
1084 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1085 printk(KERN_ERR "RARP: No suitable device found.\n");
1088 if (!ic_proto_have_if)
1089 /* Error message already printed */
1095 #ifdef IPCONFIG_BOOTP
1099 #ifdef IPCONFIG_RARP
1105 * Send requests and wait, until we get an answer. This loop
1106 * seems to be a terrible waste of CPU time, but actually there is
1107 * only one process running at all, so we don't need to use any
1108 * scheduler functions.
1109 * [Actually we could now, but the nothing else running note still
1112 printk(KERN_NOTICE "Sending %s%s%s requests .",
1114 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1115 (do_bootp && do_rarp) ? " and " : "",
1116 do_rarp ? "RARP" : "");
1118 start_jiffies = jiffies;
1120 retries = CONF_SEND_RETRIES;
1121 get_random_bytes(&timeout, sizeof(timeout));
1122 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1124 #ifdef IPCONFIG_BOOTP
1125 if (do_bootp && (d->able & IC_BOOTP))
1126 ic_bootp_send_if(d, jiffies - start_jiffies);
1128 #ifdef IPCONFIG_RARP
1129 if (do_rarp && (d->able & IC_RARP))
1133 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1134 while (time_before(jiffies, jiff) && !ic_got_reply)
1135 schedule_timeout_uninterruptible(1);
1136 #ifdef IPCONFIG_DHCP
1137 /* DHCP isn't done until we get a DHCPACK. */
1138 if ((ic_got_reply & IC_BOOTP)
1139 && (ic_proto_enabled & IC_USE_DHCP)
1140 && ic_dhcp_msgtype != DHCPACK)
1146 #endif /* IPCONFIG_DHCP */
1157 printk(" timed out!\n");
1163 timeout = timeout CONF_TIMEOUT_MULT;
1164 if (timeout > CONF_TIMEOUT_MAX)
1165 timeout = CONF_TIMEOUT_MAX;
1170 #ifdef IPCONFIG_BOOTP
1174 #ifdef IPCONFIG_RARP
1179 if (!ic_got_reply) {
1184 printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1185 ((ic_got_reply & IC_RARP) ? "RARP"
1186 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1187 NIPQUAD(ic_servaddr));
1188 printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1193 #endif /* IPCONFIG_DYNAMIC */
1195 #ifdef CONFIG_PROC_FS
1197 static int pnp_seq_show(struct seq_file *seq, void *v)
1201 if (ic_proto_used & IC_PROTO)
1202 seq_printf(seq, "#PROTO: %s\n",
1203 (ic_proto_used & IC_RARP) ? "RARP"
1204 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1206 seq_puts(seq, "#MANUAL\n");
1210 "domain %s\n", ic_domain);
1211 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1212 if (ic_nameservers[i] != NONE)
1214 "nameserver %u.%u.%u.%u\n",
1215 NIPQUAD(ic_nameservers[i]));
1217 if (ic_servaddr != NONE)
1219 "bootserver %u.%u.%u.%u\n",
1220 NIPQUAD(ic_servaddr));
1224 static int pnp_seq_open(struct inode *indoe, struct file *file)
1226 return single_open(file, pnp_seq_show, NULL);
1229 static const struct file_operations pnp_seq_fops = {
1230 .owner = THIS_MODULE,
1231 .open = pnp_seq_open,
1233 .llseek = seq_lseek,
1234 .release = single_release,
1236 #endif /* CONFIG_PROC_FS */
1239 * Extract IP address from the parameter string if needed. Note that we
1240 * need to have root_server_addr set _before_ IPConfig gets called as it
1243 __be32 __init root_nfs_parse_addr(char *name)
1250 while (octets < 4) {
1251 while (*cp >= '0' && *cp <= '9')
1253 if (cp == cq || cp - cq > 3)
1255 if (*cp == '.' || octets == 3)
1261 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1264 addr = in_aton(name);
1265 memmove(name, cp, strlen(cp) + 1);
1273 * IP Autoconfig dispatcher.
1276 static int __init ip_auto_config(void)
1280 #ifdef CONFIG_PROC_FS
1281 proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1282 #endif /* CONFIG_PROC_FS */
1287 DBG(("IP-Config: Entered.\n"));
1288 #ifdef IPCONFIG_DYNAMIC
1291 /* Give hardware a chance to settle */
1292 msleep(CONF_PRE_OPEN);
1294 /* Setup all network devices */
1295 if (ic_open_devs() < 0)
1298 /* Give drivers a chance to settle */
1299 ssleep(CONF_POST_OPEN);
1302 * If the config information is insufficient (e.g., our IP address or
1303 * IP address of the boot server is missing or we have multiple network
1304 * interfaces and no default was set), use BOOTP or RARP to get the
1307 if (ic_myaddr == NONE ||
1308 #ifdef CONFIG_ROOT_NFS
1309 (root_server_addr == NONE
1310 && ic_servaddr == NONE
1311 && ROOT_DEV == Root_NFS) ||
1313 ic_first_dev->next) {
1314 #ifdef IPCONFIG_DYNAMIC
1316 int retries = CONF_OPEN_RETRIES;
1318 if (ic_dynamic() < 0) {
1322 * I don't know why, but sometimes the
1323 * eepro100 driver (at least) gets upset and
1324 * doesn't work the first time it's opened.
1325 * But then if you close it and reopen it, it
1326 * works just fine. So we need to try that at
1327 * least once before giving up.
1329 * Also, if the root will be NFS-mounted, we
1330 * have nowhere to go if DHCP fails. So we
1331 * just have to keep trying forever.
1335 #ifdef CONFIG_ROOT_NFS
1336 if (ROOT_DEV == Root_NFS) {
1338 "IP-Config: Retrying forever (NFS root)...\n");
1345 "IP-Config: Reopening network devices...\n");
1349 /* Oh, well. At least we tried. */
1350 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1353 #else /* !DYNAMIC */
1354 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1357 #endif /* IPCONFIG_DYNAMIC */
1359 /* Device selected manually or only one device -> use it */
1360 ic_dev = ic_first_dev->dev;
1363 addr = root_nfs_parse_addr(root_server_path);
1364 if (root_server_addr == NONE)
1365 root_server_addr = addr;
1368 * Use defaults whereever applicable.
1370 if (ic_defaults() < 0)
1374 * Close all network devices except the device we've
1375 * autoconfigured and set up routes.
1378 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1382 * Record which protocol was actually used.
1384 #ifdef IPCONFIG_DYNAMIC
1385 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1388 #ifndef IPCONFIG_SILENT
1390 * Clue in the operator.
1392 printk("IP-Config: Complete:");
1393 printk("\n device=%s", ic_dev->name);
1394 printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1395 printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1396 printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1397 printk(",\n host=%s, domain=%s, nis-domain=%s",
1398 utsname()->nodename, ic_domain, utsname()->domainname);
1399 printk(",\n bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1400 printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1401 printk(", rootpath=%s", root_server_path);
1403 #endif /* !SILENT */
1408 late_initcall(ip_auto_config);
1412 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1413 * command line parameter. See Documentation/nfsroot.txt.
1415 static int __init ic_proto_name(char *name)
1417 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1420 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1423 #ifdef CONFIG_IP_PNP_DHCP
1424 else if (!strcmp(name, "dhcp")) {
1425 ic_proto_enabled &= ~IC_RARP;
1429 #ifdef CONFIG_IP_PNP_BOOTP
1430 else if (!strcmp(name, "bootp")) {
1431 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1435 #ifdef CONFIG_IP_PNP_RARP
1436 else if (!strcmp(name, "rarp")) {
1437 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1441 #ifdef IPCONFIG_DYNAMIC
1442 else if (!strcmp(name, "both")) {
1443 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1450 static int __init ip_auto_config_setup(char *addrs)
1455 ic_set_manually = 1;
1459 * If any dhcp, bootp etc options are set, leave autoconfig on
1460 * and skip the below static IP processing.
1462 if (ic_proto_name(addrs))
1465 /* If no static IP is given, turn off autoconfig and bail. */
1467 strcmp(addrs, "off") == 0 ||
1468 strcmp(addrs, "none") == 0) {
1473 /* Parse string for static IP assignment. */
1476 if ((cp = strchr(ip, ':')))
1478 if (strlen(ip) > 0) {
1479 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1482 if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1486 if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1490 if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1494 if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1498 if ((dp = strchr(ip, '.'))) {
1500 strlcpy(utsname()->domainname, dp,
1501 sizeof(utsname()->domainname));
1503 strlcpy(utsname()->nodename, ip,
1504 sizeof(utsname()->nodename));
1505 ic_host_name_set = 1;
1508 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1511 if (ic_proto_name(ip) == 0 &&
1512 ic_myaddr == NONE) {
1525 static int __init nfsaddrs_config_setup(char *addrs)
1527 return ip_auto_config_setup(addrs);
1530 static int __init vendor_class_identifier_setup(char *addrs)
1532 if (strlcpy(vendor_class_identifier, addrs,
1533 sizeof(vendor_class_identifier))
1534 >= sizeof(vendor_class_identifier))
1535 printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1536 vendor_class_identifier);
1540 __setup("ip=", ip_auto_config_setup);
1541 __setup("nfsaddrs=", nfsaddrs_config_setup);
1542 __setup("dhcpclass=", vendor_class_identifier_setup);