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)
106 #define ANY __constant_htonl(INADDR_ANY)
109 * Public IP configuration
112 /* This is used by platforms which might be able to set the ipconfig
113 * variables using firmware environment vars. If this is set, it will
114 * ignore such firmware variables.
116 int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
118 static int ic_enable __initdata = 0; /* IP config enabled? */
120 /* Protocol choice */
121 int ic_proto_enabled __initdata = 0
122 #ifdef IPCONFIG_BOOTP
125 #ifdef CONFIG_IP_PNP_DHCP
133 static int ic_host_name_set __initdata = 0; /* Host name set by us? */
135 __be32 ic_myaddr = NONE; /* My IP address */
136 static __be32 ic_netmask = NONE; /* Netmask for local subnet */
137 __be32 ic_gateway = NONE; /* Gateway IP address */
139 __be32 ic_servaddr = NONE; /* Boot server IP address */
141 __be32 root_server_addr = NONE; /* Address of NFS server */
142 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
144 /* vendor class identifier */
145 static char vendor_class_identifier[253] __initdata;
147 /* Persistent data: */
149 static int ic_proto_used; /* Protocol used, if any */
150 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
151 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
157 /* Name of user-selected boot device */
158 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
160 /* Protocols supported by available interfaces */
161 static int ic_proto_have_if __initdata = 0;
163 #ifdef IPCONFIG_DYNAMIC
164 static DEFINE_SPINLOCK(ic_recv_lock);
165 static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
168 static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
177 struct ic_device *next;
178 struct net_device *dev;
179 unsigned short flags;
184 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
185 static struct net_device *ic_dev __initdata = NULL; /* Selected device */
187 static int __init ic_open_devs(void)
189 struct ic_device *d, **last;
190 struct net_device *dev;
191 unsigned short oflags;
193 last = &ic_first_dev;
196 /* bring loopback device up first */
197 for_each_netdev(&init_net, dev) {
198 if (!(dev->flags & IFF_LOOPBACK))
200 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
201 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
204 for_each_netdev(&init_net, dev) {
205 if (dev->flags & IFF_LOOPBACK)
207 if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
208 (!(dev->flags & IFF_LOOPBACK) &&
209 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
210 strncmp(dev->name, "dummy", 5))) {
215 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
216 if (!(dev->flags & IFF_NOARP))
218 able &= ic_proto_enabled;
219 if (ic_proto_enabled && !able)
222 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
223 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
226 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
236 get_random_bytes(&d->xid, sizeof(__be32));
239 ic_proto_have_if |= able;
240 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
241 dev->name, able, d->xid));
249 if (user_dev_name[0])
250 printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
252 printk(KERN_ERR "IP-Config: No network devices available.\n");
258 static void __init ic_close_devs(void)
260 struct ic_device *d, *next;
261 struct net_device *dev;
269 DBG(("IP-Config: Downing %s\n", dev->name));
270 dev_change_flags(dev, d->flags);
278 * Interface to various network functions.
282 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
284 sin->sin_family = AF_INET;
285 sin->sin_addr.s_addr = addr;
286 sin->sin_port = port;
289 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
293 mm_segment_t oldfs = get_fs();
295 res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
300 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
304 mm_segment_t oldfs = get_fs();
306 res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
312 * Set up interface addresses and routes.
315 static int __init ic_setup_if(void)
318 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
321 memset(&ir, 0, sizeof(ir));
322 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
323 set_sockaddr(sin, ic_myaddr, 0);
324 if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
325 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
328 set_sockaddr(sin, ic_netmask, 0);
329 if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
330 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
333 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
334 if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
335 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
341 static int __init ic_setup_routes(void)
343 /* No need to setup device routes, only the default route... */
345 if (ic_gateway != NONE) {
349 memset(&rm, 0, sizeof(rm));
350 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
351 printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
354 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
355 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
356 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
357 rm.rt_flags = RTF_UP | RTF_GATEWAY;
358 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
359 printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
368 * Fill in default values for all missing parameters.
371 static int __init ic_defaults(void)
374 * At this point we have no userspace running so need not
375 * claim locks on system_utsname
378 if (!ic_host_name_set)
379 sprintf(init_utsname()->nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
381 if (root_server_addr == NONE)
382 root_server_addr = ic_servaddr;
384 if (ic_netmask == NONE) {
385 if (IN_CLASSA(ntohl(ic_myaddr)))
386 ic_netmask = htonl(IN_CLASSA_NET);
387 else if (IN_CLASSB(ntohl(ic_myaddr)))
388 ic_netmask = htonl(IN_CLASSB_NET);
389 else if (IN_CLASSC(ntohl(ic_myaddr)))
390 ic_netmask = htonl(IN_CLASSC_NET);
392 printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
396 printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
408 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
410 static struct packet_type rarp_packet_type __initdata = {
411 .type = __constant_htons(ETH_P_RARP),
412 .func = ic_rarp_recv,
415 static inline void ic_rarp_init(void)
417 dev_add_pack(&rarp_packet_type);
420 static inline void ic_rarp_cleanup(void)
422 dev_remove_pack(&rarp_packet_type);
426 * Process received RARP packet.
429 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
432 unsigned char *rarp_ptr;
434 unsigned char *sha, *tha; /* s for "source", t for "target" */
437 if (dev->nd_net != &init_net)
440 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
443 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
446 /* Basic sanity checks can be done without the lock. */
447 rarp = (struct arphdr *)skb_transport_header(skb);
449 /* If this test doesn't pass, it's not IP, or we should
452 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
455 /* If it's not a RARP reply, delete it. */
456 if (rarp->ar_op != htons(ARPOP_RREPLY))
459 /* If it's not Ethernet, delete it. */
460 if (rarp->ar_pro != htons(ETH_P_IP))
463 if (!pskb_may_pull(skb,
464 sizeof(struct arphdr) +
465 (2 * dev->addr_len) +
469 /* OK, it is all there and looks valid, process... */
470 rarp = (struct arphdr *)skb_transport_header(skb);
471 rarp_ptr = (unsigned char *) (rarp + 1);
473 /* One reply at a time, please. */
474 spin_lock(&ic_recv_lock);
476 /* If we already have a reply, just drop the packet */
480 /* Find the ic_device that the packet arrived on */
482 while (d && d->dev != dev)
485 goto drop_unlock; /* should never happen */
487 /* Extract variable-width fields */
489 rarp_ptr += dev->addr_len;
490 memcpy(&sip, rarp_ptr, 4);
493 rarp_ptr += dev->addr_len;
494 memcpy(&tip, rarp_ptr, 4);
496 /* Discard packets which are not meant for us. */
497 if (memcmp(tha, dev->dev_addr, dev->addr_len))
500 /* Discard packets which are not from specified server. */
501 if (ic_servaddr != NONE && ic_servaddr != sip)
504 /* We have a winner! */
506 if (ic_myaddr == NONE)
509 ic_got_reply = IC_RARP;
512 /* Show's over. Nothing to see here. */
513 spin_unlock(&ic_recv_lock);
516 /* Throw the packet out. */
523 * Send RARP request packet over a single interface.
525 static void __init ic_rarp_send_if(struct ic_device *d)
527 struct net_device *dev = d->dev;
528 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
529 dev->dev_addr, dev->dev_addr);
534 * DHCP/BOOTP support.
537 #ifdef IPCONFIG_BOOTP
539 struct bootp_pkt { /* BOOTP packet format */
540 struct iphdr iph; /* IP header */
541 struct udphdr udph; /* UDP header */
542 u8 op; /* 1=request, 2=reply */
543 u8 htype; /* HW address type */
544 u8 hlen; /* HW address length */
545 u8 hops; /* Used only by gateways */
546 __be32 xid; /* Transaction ID */
547 __be16 secs; /* Seconds since we started */
548 __be16 flags; /* Just what it says */
549 __be32 client_ip; /* Client's IP address if known */
550 __be32 your_ip; /* Assigned IP address */
551 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
552 __be32 relay_ip; /* IP address of BOOTP relay */
553 u8 hw_addr[16]; /* Client's HW address */
554 u8 serv_name[64]; /* Server host name */
555 u8 boot_file[128]; /* Name of boot file */
556 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
560 #define BOOTP_REQUEST 1
561 #define BOOTP_REPLY 2
563 /* DHCP message types */
564 #define DHCPDISCOVER 1
566 #define DHCPREQUEST 3
567 #define DHCPDECLINE 4
570 #define DHCPRELEASE 7
573 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
575 static struct packet_type bootp_packet_type __initdata = {
576 .type = __constant_htons(ETH_P_IP),
577 .func = ic_bootp_recv,
582 * Initialize DHCP/BOOTP extension fields in the request.
585 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
590 ic_dhcp_init_options(u8 *options)
592 u8 mt = ((ic_servaddr == NONE)
593 ? DHCPDISCOVER : DHCPREQUEST);
597 #ifdef IPCONFIG_DEBUG
598 printk("DHCP: Sending message type %d\n", mt);
601 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
604 *e++ = 53; /* DHCP message type */
608 if (mt == DHCPREQUEST) {
609 *e++ = 54; /* Server ID (IP address) */
611 memcpy(e, &ic_servaddr, 4);
614 *e++ = 50; /* Requested IP address */
616 memcpy(e, &ic_myaddr, 4);
622 static const u8 ic_req_params[] = {
624 3, /* Default gateway */
627 15, /* Domain name */
629 40, /* NIS domain name */
632 *e++ = 55; /* Parameter request list */
633 *e++ = sizeof(ic_req_params);
634 memcpy(e, ic_req_params, sizeof(ic_req_params));
635 e += sizeof(ic_req_params);
637 if (*vendor_class_identifier) {
638 printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
639 vendor_class_identifier);
640 *e++ = 60; /* Class-identifier */
641 len = strlen(vendor_class_identifier);
643 memcpy(e, vendor_class_identifier, len);
648 *e++ = 255; /* End of the list */
651 #endif /* IPCONFIG_DHCP */
653 static void __init ic_bootp_init_ext(u8 *e)
655 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
657 *e++ = 1; /* Subnet mask request */
660 *e++ = 3; /* Default gateway request */
663 *e++ = 5; /* Name server request */
666 *e++ = 12; /* Host name request */
669 *e++ = 40; /* NIS Domain name request */
672 *e++ = 17; /* Boot path */
676 *e++ = 57; /* set extension buffer size for reply */
678 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
681 *e++ = 255; /* End of the list */
686 * Initialize the DHCP/BOOTP mechanism.
688 static inline void ic_bootp_init(void)
692 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
693 ic_nameservers[i] = NONE;
695 dev_add_pack(&bootp_packet_type);
700 * DHCP/BOOTP cleanup.
702 static inline void ic_bootp_cleanup(void)
704 dev_remove_pack(&bootp_packet_type);
709 * Send DHCP/BOOTP request to single interface.
711 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
713 struct net_device *dev = d->dev;
716 int hh_len = LL_RESERVED_SPACE(dev);
719 /* Allocate packet */
720 skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
723 skb_reserve(skb, hh_len);
724 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
725 memset(b, 0, sizeof(struct bootp_pkt));
727 /* Construct IP header */
728 skb_reset_network_header(skb);
732 h->tot_len = htons(sizeof(struct bootp_pkt));
733 h->frag_off = htons(IP_DF);
735 h->protocol = IPPROTO_UDP;
736 h->daddr = htonl(INADDR_BROADCAST);
737 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
739 /* Construct UDP header */
740 b->udph.source = htons(68);
741 b->udph.dest = htons(67);
742 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
743 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
745 /* Construct DHCP/BOOTP header */
746 b->op = BOOTP_REQUEST;
747 if (dev->type < 256) /* check for false types */
748 b->htype = dev->type;
749 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
750 b->htype = ARPHRD_IEEE802;
751 else if (dev->type == ARPHRD_FDDI)
752 b->htype = ARPHRD_ETHER;
754 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
755 b->htype = dev->type; /* can cause undefined behavior */
758 /* server_ip and your_ip address are both already zero per RFC2131 */
759 b->hlen = dev->addr_len;
760 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
761 b->secs = htons(jiffies_diff / HZ);
764 /* add DHCP options or BOOTP extensions */
766 if (ic_proto_enabled & IC_USE_DHCP)
767 ic_dhcp_init_options(b->exten);
770 ic_bootp_init_ext(b->exten);
772 /* Chain packet down the line... */
774 skb->protocol = htons(ETH_P_IP);
775 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
776 dev->broadcast, dev->dev_addr, skb->len) < 0 ||
777 dev_queue_xmit(skb) < 0)
783 * Copy BOOTP-supplied string if not already set.
785 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
791 memcpy(dest, src, len);
798 * Process BOOTP extensions.
800 static void __init ic_do_bootp_ext(u8 *ext)
805 #ifdef IPCONFIG_DEBUG
808 printk("DHCP/BOOTP: Got extension %d:",*ext);
809 for (c=ext+2; c<ext+2+ext[1]; c++)
815 case 1: /* Subnet mask */
816 if (ic_netmask == NONE)
817 memcpy(&ic_netmask, ext+1, 4);
819 case 3: /* Default gateway */
820 if (ic_gateway == NONE)
821 memcpy(&ic_gateway, ext+1, 4);
823 case 6: /* DNS server */
825 if (servers > CONF_NAMESERVERS_MAX)
826 servers = CONF_NAMESERVERS_MAX;
827 for (i = 0; i < servers; i++) {
828 if (ic_nameservers[i] == NONE)
829 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
832 case 12: /* Host name */
833 ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
834 ic_host_name_set = 1;
836 case 15: /* Domain name (DNS) */
837 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
839 case 17: /* Root path */
840 if (!root_server_path[0])
841 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
843 case 40: /* NIS Domain name (_not_ DNS) */
844 ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
851 * Receive BOOTP reply.
853 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
860 if (dev->nd_net != &init_net)
863 /* Perform verifications before taking the lock. */
864 if (skb->pkt_type == PACKET_OTHERHOST)
867 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
870 if (!pskb_may_pull(skb,
871 sizeof(struct iphdr) +
872 sizeof(struct udphdr)))
875 b = (struct bootp_pkt *)skb_network_header(skb);
878 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
881 /* Fragments are not supported */
882 if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
884 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
889 if (skb->len < ntohs(h->tot_len))
892 if (ip_fast_csum((char *) h, h->ihl))
895 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
898 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
901 len = ntohs(b->udph.len) - sizeof(struct udphdr);
902 ext_len = len - (sizeof(*b) -
903 sizeof(struct iphdr) -
904 sizeof(struct udphdr) -
909 /* Ok the front looks good, make sure we can get at the rest. */
910 if (!pskb_may_pull(skb, skb->len))
913 b = (struct bootp_pkt *)skb_network_header(skb);
916 /* One reply at a time, please. */
917 spin_lock(&ic_recv_lock);
919 /* If we already have a reply, just drop the packet */
923 /* Find the ic_device that the packet arrived on */
925 while (d && d->dev != dev)
928 goto drop_unlock; /* should never happen */
930 /* Is it a reply to our BOOTP request? */
931 if (b->op != BOOTP_REPLY ||
934 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
940 /* Parse extensions */
942 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
943 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
947 if (ic_proto_enabled & IC_USE_DHCP) {
948 __be32 server_id = NONE;
952 while (ext < end && *ext != 0xff) {
954 if (*opt == 0) /* Padding */
960 case 53: /* Message type */
964 case 54: /* Server ID (IP address) */
966 memcpy(&server_id, opt + 2, 4);
971 #ifdef IPCONFIG_DEBUG
972 printk("DHCP: Got message type %d\n", mt);
977 /* While in the process of accepting one offer,
980 if (ic_myaddr != NONE)
983 /* Let's accept that offer. */
984 ic_myaddr = b->your_ip;
985 ic_servaddr = server_id;
986 #ifdef IPCONFIG_DEBUG
987 printk("DHCP: Offered address %u.%u.%u.%u",
989 printk(" by server %u.%u.%u.%u\n",
990 NIPQUAD(ic_servaddr));
992 /* The DHCP indicated server address takes
993 * precedence over the bootp header one if
994 * they are different.
996 if ((server_id != NONE) &&
997 (b->server_ip != server_id))
998 b->server_ip = ic_servaddr;
1002 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1009 /* Urque. Forget it*/
1015 ic_dhcp_msgtype = mt;
1018 #endif /* IPCONFIG_DHCP */
1021 while (ext < end && *ext != 0xff) {
1023 if (*opt == 0) /* Padding */
1027 ic_do_bootp_ext(opt);
1031 /* We have a winner! */
1033 ic_myaddr = b->your_ip;
1034 ic_servaddr = b->server_ip;
1035 if (ic_gateway == NONE && b->relay_ip)
1036 ic_gateway = b->relay_ip;
1037 if (ic_nameservers[0] == NONE)
1038 ic_nameservers[0] = ic_servaddr;
1039 ic_got_reply = IC_BOOTP;
1042 /* Show's over. Nothing to see here. */
1043 spin_unlock(&ic_recv_lock);
1046 /* Throw the packet out. */
1057 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1060 #ifdef IPCONFIG_DYNAMIC
1062 static int __init ic_dynamic(void)
1065 struct ic_device *d;
1066 unsigned long start_jiffies, timeout, jiff;
1067 int do_bootp = ic_proto_have_if & IC_BOOTP;
1068 int do_rarp = ic_proto_have_if & IC_RARP;
1071 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1072 * This routine gets only called when some pieces of information
1073 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1075 if (!ic_proto_enabled) {
1076 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1080 #ifdef IPCONFIG_BOOTP
1081 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1082 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1084 #ifdef IPCONFIG_RARP
1085 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1086 printk(KERN_ERR "RARP: No suitable device found.\n");
1089 if (!ic_proto_have_if)
1090 /* Error message already printed */
1096 #ifdef IPCONFIG_BOOTP
1100 #ifdef IPCONFIG_RARP
1106 * Send requests and wait, until we get an answer. This loop
1107 * seems to be a terrible waste of CPU time, but actually there is
1108 * only one process running at all, so we don't need to use any
1109 * scheduler functions.
1110 * [Actually we could now, but the nothing else running note still
1113 printk(KERN_NOTICE "Sending %s%s%s requests .",
1115 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1116 (do_bootp && do_rarp) ? " and " : "",
1117 do_rarp ? "RARP" : "");
1119 start_jiffies = jiffies;
1121 retries = CONF_SEND_RETRIES;
1122 get_random_bytes(&timeout, sizeof(timeout));
1123 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1125 #ifdef IPCONFIG_BOOTP
1126 if (do_bootp && (d->able & IC_BOOTP))
1127 ic_bootp_send_if(d, jiffies - start_jiffies);
1129 #ifdef IPCONFIG_RARP
1130 if (do_rarp && (d->able & IC_RARP))
1134 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1135 while (time_before(jiffies, jiff) && !ic_got_reply)
1136 schedule_timeout_uninterruptible(1);
1137 #ifdef IPCONFIG_DHCP
1138 /* DHCP isn't done until we get a DHCPACK. */
1139 if ((ic_got_reply & IC_BOOTP)
1140 && (ic_proto_enabled & IC_USE_DHCP)
1141 && ic_dhcp_msgtype != DHCPACK)
1147 #endif /* IPCONFIG_DHCP */
1158 printk(" timed out!\n");
1164 timeout = timeout CONF_TIMEOUT_MULT;
1165 if (timeout > CONF_TIMEOUT_MAX)
1166 timeout = CONF_TIMEOUT_MAX;
1171 #ifdef IPCONFIG_BOOTP
1175 #ifdef IPCONFIG_RARP
1180 if (!ic_got_reply) {
1185 printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1186 ((ic_got_reply & IC_RARP) ? "RARP"
1187 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1188 NIPQUAD(ic_servaddr));
1189 printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1194 #endif /* IPCONFIG_DYNAMIC */
1196 #ifdef CONFIG_PROC_FS
1198 static int pnp_seq_show(struct seq_file *seq, void *v)
1202 if (ic_proto_used & IC_PROTO)
1203 seq_printf(seq, "#PROTO: %s\n",
1204 (ic_proto_used & IC_RARP) ? "RARP"
1205 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1207 seq_puts(seq, "#MANUAL\n");
1211 "domain %s\n", ic_domain);
1212 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1213 if (ic_nameservers[i] != NONE)
1215 "nameserver %u.%u.%u.%u\n",
1216 NIPQUAD(ic_nameservers[i]));
1218 if (ic_servaddr != NONE)
1220 "bootserver %u.%u.%u.%u\n",
1221 NIPQUAD(ic_servaddr));
1225 static int pnp_seq_open(struct inode *indoe, struct file *file)
1227 return single_open(file, pnp_seq_show, NULL);
1230 static const struct file_operations pnp_seq_fops = {
1231 .owner = THIS_MODULE,
1232 .open = pnp_seq_open,
1234 .llseek = seq_lseek,
1235 .release = single_release,
1237 #endif /* CONFIG_PROC_FS */
1240 * Extract IP address from the parameter string if needed. Note that we
1241 * need to have root_server_addr set _before_ IPConfig gets called as it
1244 __be32 __init root_nfs_parse_addr(char *name)
1251 while (octets < 4) {
1252 while (*cp >= '0' && *cp <= '9')
1254 if (cp == cq || cp - cq > 3)
1256 if (*cp == '.' || octets == 3)
1262 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1265 addr = in_aton(name);
1266 memmove(name, cp, strlen(cp) + 1);
1274 * IP Autoconfig dispatcher.
1277 static int __init ip_auto_config(void)
1281 #ifdef CONFIG_PROC_FS
1282 proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1283 #endif /* CONFIG_PROC_FS */
1288 DBG(("IP-Config: Entered.\n"));
1289 #ifdef IPCONFIG_DYNAMIC
1292 /* Give hardware a chance to settle */
1293 msleep(CONF_PRE_OPEN);
1295 /* Setup all network devices */
1296 if (ic_open_devs() < 0)
1299 /* Give drivers a chance to settle */
1300 ssleep(CONF_POST_OPEN);
1303 * If the config information is insufficient (e.g., our IP address or
1304 * IP address of the boot server is missing or we have multiple network
1305 * interfaces and no default was set), use BOOTP or RARP to get the
1308 if (ic_myaddr == NONE ||
1309 #ifdef CONFIG_ROOT_NFS
1310 (root_server_addr == NONE
1311 && ic_servaddr == NONE
1312 && ROOT_DEV == Root_NFS) ||
1314 ic_first_dev->next) {
1315 #ifdef IPCONFIG_DYNAMIC
1317 int retries = CONF_OPEN_RETRIES;
1319 if (ic_dynamic() < 0) {
1323 * I don't know why, but sometimes the
1324 * eepro100 driver (at least) gets upset and
1325 * doesn't work the first time it's opened.
1326 * But then if you close it and reopen it, it
1327 * works just fine. So we need to try that at
1328 * least once before giving up.
1330 * Also, if the root will be NFS-mounted, we
1331 * have nowhere to go if DHCP fails. So we
1332 * just have to keep trying forever.
1336 #ifdef CONFIG_ROOT_NFS
1337 if (ROOT_DEV == Root_NFS) {
1339 "IP-Config: Retrying forever (NFS root)...\n");
1346 "IP-Config: Reopening network devices...\n");
1350 /* Oh, well. At least we tried. */
1351 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1354 #else /* !DYNAMIC */
1355 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1358 #endif /* IPCONFIG_DYNAMIC */
1360 /* Device selected manually or only one device -> use it */
1361 ic_dev = ic_first_dev->dev;
1364 addr = root_nfs_parse_addr(root_server_path);
1365 if (root_server_addr == NONE)
1366 root_server_addr = addr;
1369 * Use defaults whereever applicable.
1371 if (ic_defaults() < 0)
1375 * Close all network devices except the device we've
1376 * autoconfigured and set up routes.
1379 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1383 * Record which protocol was actually used.
1385 #ifdef IPCONFIG_DYNAMIC
1386 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1389 #ifndef IPCONFIG_SILENT
1391 * Clue in the operator.
1393 printk("IP-Config: Complete:");
1394 printk("\n device=%s", ic_dev->name);
1395 printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1396 printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1397 printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1398 printk(",\n host=%s, domain=%s, nis-domain=%s",
1399 utsname()->nodename, ic_domain, utsname()->domainname);
1400 printk(",\n bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1401 printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1402 printk(", rootpath=%s", root_server_path);
1404 #endif /* !SILENT */
1409 late_initcall(ip_auto_config);
1413 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1414 * command line parameter. See Documentation/filesystems/nfsroot.txt.
1416 static int __init ic_proto_name(char *name)
1418 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1421 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1424 #ifdef CONFIG_IP_PNP_DHCP
1425 else if (!strcmp(name, "dhcp")) {
1426 ic_proto_enabled &= ~IC_RARP;
1430 #ifdef CONFIG_IP_PNP_BOOTP
1431 else if (!strcmp(name, "bootp")) {
1432 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1436 #ifdef CONFIG_IP_PNP_RARP
1437 else if (!strcmp(name, "rarp")) {
1438 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1442 #ifdef IPCONFIG_DYNAMIC
1443 else if (!strcmp(name, "both")) {
1444 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1451 static int __init ip_auto_config_setup(char *addrs)
1456 ic_set_manually = 1;
1460 * If any dhcp, bootp etc options are set, leave autoconfig on
1461 * and skip the below static IP processing.
1463 if (ic_proto_name(addrs))
1466 /* If no static IP is given, turn off autoconfig and bail. */
1468 strcmp(addrs, "off") == 0 ||
1469 strcmp(addrs, "none") == 0) {
1474 /* Parse string for static IP assignment. */
1477 if ((cp = strchr(ip, ':')))
1479 if (strlen(ip) > 0) {
1480 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1483 if ((ic_myaddr = in_aton(ip)) == ANY)
1487 if ((ic_servaddr = in_aton(ip)) == ANY)
1491 if ((ic_gateway = in_aton(ip)) == ANY)
1495 if ((ic_netmask = in_aton(ip)) == ANY)
1499 if ((dp = strchr(ip, '.'))) {
1501 strlcpy(utsname()->domainname, dp,
1502 sizeof(utsname()->domainname));
1504 strlcpy(utsname()->nodename, ip,
1505 sizeof(utsname()->nodename));
1506 ic_host_name_set = 1;
1509 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1512 if (ic_proto_name(ip) == 0 &&
1513 ic_myaddr == NONE) {
1526 static int __init nfsaddrs_config_setup(char *addrs)
1528 return ip_auto_config_setup(addrs);
1531 static int __init vendor_class_identifier_setup(char *addrs)
1533 if (strlcpy(vendor_class_identifier, addrs,
1534 sizeof(vendor_class_identifier))
1535 >= sizeof(vendor_class_identifier))
1536 printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1537 vendor_class_identifier);
1541 __setup("ip=", ip_auto_config_setup);
1542 __setup("nfsaddrs=", nfsaddrs_config_setup);
1543 __setup("dhcpclass=", vendor_class_identifier_setup);