2 * Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
3 * user-supplied information to configure own IP address and routes.
5 * Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
7 * Derived from network configuration code in fs/nfs/nfsroot.c,
8 * originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
10 * BOOTP rewritten to construct and analyse packets itself instead
11 * of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
12 * -- MJ, December 1998
14 * Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
15 * initialization scheme.
16 * - Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
18 * DHCP support added. To users this looks like a whole separate
19 * protocol, but we know it's just a bag on the side of BOOTP.
20 * -- Chip Salzenberg <chip@valinux.com>, May 2000
22 * Ported DHCP support from 2.2.16 to 2.4.0-test4
23 * -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
25 * Merged changes from 2.2.19 into 2.4.3
26 * -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
28 * Multiple Nameservers in /proc/net/pnp
29 * -- Josef Siemes <jsiemes@web.de>, Aug 2002
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/kernel.h>
35 #include <linux/jiffies.h>
36 #include <linux/random.h>
37 #include <linux/init.h>
38 #include <linux/utsname.h>
41 #include <linux/inet.h>
42 #include <linux/inetdevice.h>
43 #include <linux/netdevice.h>
44 #include <linux/if_arp.h>
45 #include <linux/skbuff.h>
47 #include <linux/socket.h>
48 #include <linux/route.h>
49 #include <linux/udp.h>
50 #include <linux/proc_fs.h>
51 #include <linux/seq_file.h>
52 #include <linux/major.h>
53 #include <linux/root_dev.h>
54 #include <linux/delay.h>
55 #include <linux/nfs_fs.h>
56 #include <linux/slab.h>
57 #include <net/net_namespace.h>
60 #include <net/ipconfig.h>
61 #include <net/route.h>
63 #include <asm/uaccess.h>
64 #include <net/checksum.h>
65 #include <asm/processor.h>
67 /* Define this to allow debugging output */
71 #define DBG(x) printk x
73 #define DBG(x) do { } while(0)
76 #if defined(CONFIG_IP_PNP_DHCP)
79 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
80 #define IPCONFIG_BOOTP
82 #if defined(CONFIG_IP_PNP_RARP)
85 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
86 #define IPCONFIG_DYNAMIC
89 /* Define the friendly delay before and after opening net devices */
90 #define CONF_POST_OPEN 10 /* After opening: 10 msecs */
91 #define CONF_CARRIER_TIMEOUT 120000 /* Wait for carrier timeout */
93 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
94 #define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */
95 #define CONF_SEND_RETRIES 6 /* Send six requests per open */
96 #define CONF_INTER_TIMEOUT (HZ/2) /* Inter-device timeout: 1/2 second */
97 #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
98 #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
99 #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
100 #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
101 #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
102 - '3' from resolv.h */
104 #define NONE cpu_to_be32(INADDR_NONE)
105 #define ANY cpu_to_be32(INADDR_ANY)
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 u32 ic_dev_xid; /* Device under configuration */
145 /* vendor class identifier */
146 static char vendor_class_identifier[253] __initdata;
148 /* Persistent data: */
150 static int ic_proto_used; /* Protocol used, if any */
151 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
152 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
158 /* Name of user-selected boot device */
159 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
161 /* Protocols supported by available interfaces */
162 static int ic_proto_have_if __initdata = 0;
164 /* MTU for boot device */
165 static int ic_dev_mtu __initdata = 0;
167 #ifdef IPCONFIG_DYNAMIC
168 static DEFINE_SPINLOCK(ic_recv_lock);
169 static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
172 static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
181 struct ic_device *next;
182 struct net_device *dev;
183 unsigned short flags;
188 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
189 static struct net_device *ic_dev __initdata = NULL; /* Selected device */
191 static bool __init ic_is_init_dev(struct net_device *dev)
193 if (dev->flags & IFF_LOOPBACK)
195 return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
196 (!(dev->flags & IFF_LOOPBACK) &&
197 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
198 strncmp(dev->name, "dummy", 5));
201 static int __init ic_open_devs(void)
203 struct ic_device *d, **last;
204 struct net_device *dev;
205 unsigned short oflags;
208 last = &ic_first_dev;
211 /* bring loopback device up first */
212 for_each_netdev(&init_net, dev) {
213 if (!(dev->flags & IFF_LOOPBACK))
215 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
216 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
219 for_each_netdev(&init_net, dev) {
220 if (ic_is_init_dev(dev)) {
225 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
226 if (!(dev->flags & IFF_NOARP))
228 able &= ic_proto_enabled;
229 if (ic_proto_enabled && !able)
232 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
233 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
236 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
246 get_random_bytes(&d->xid, sizeof(__be32));
249 ic_proto_have_if |= able;
250 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
251 dev->name, able, d->xid));
255 /* wait for a carrier on at least one device */
257 while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
258 for_each_netdev(&init_net, dev)
259 if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
270 if (user_dev_name[0])
271 printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
273 printk(KERN_ERR "IP-Config: No network devices available.\n");
279 static void __init ic_close_devs(void)
281 struct ic_device *d, *next;
282 struct net_device *dev;
290 DBG(("IP-Config: Downing %s\n", dev->name));
291 dev_change_flags(dev, d->flags);
299 * Interface to various network functions.
303 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
305 sin->sin_family = AF_INET;
306 sin->sin_addr.s_addr = addr;
307 sin->sin_port = port;
310 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
314 mm_segment_t oldfs = get_fs();
316 res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
321 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
325 mm_segment_t oldfs = get_fs();
327 res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
332 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
336 mm_segment_t oldfs = get_fs();
338 res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
344 * Set up interface addresses and routes.
347 static int __init ic_setup_if(void)
350 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
353 memset(&ir, 0, sizeof(ir));
354 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
355 set_sockaddr(sin, ic_myaddr, 0);
356 if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
357 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
360 set_sockaddr(sin, ic_netmask, 0);
361 if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
362 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
365 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
366 if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
367 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
370 /* Handle the case where we need non-standard MTU on the boot link (a network
371 * using jumbo frames, for instance). If we can't set the mtu, don't error
372 * out, we'll try to muddle along.
374 if (ic_dev_mtu != 0) {
375 strcpy(ir.ifr_name, ic_dev->name);
376 ir.ifr_mtu = ic_dev_mtu;
377 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
378 printk(KERN_ERR "IP-Config: Unable to set interface mtu to %d (%d).\n",
384 static int __init ic_setup_routes(void)
386 /* No need to setup device routes, only the default route... */
388 if (ic_gateway != NONE) {
392 memset(&rm, 0, sizeof(rm));
393 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
394 printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
397 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
398 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
399 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
400 rm.rt_flags = RTF_UP | RTF_GATEWAY;
401 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
402 printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
411 * Fill in default values for all missing parameters.
414 static int __init ic_defaults(void)
417 * At this point we have no userspace running so need not
418 * claim locks on system_utsname
421 if (!ic_host_name_set)
422 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
424 if (root_server_addr == NONE)
425 root_server_addr = ic_servaddr;
427 if (ic_netmask == NONE) {
428 if (IN_CLASSA(ntohl(ic_myaddr)))
429 ic_netmask = htonl(IN_CLASSA_NET);
430 else if (IN_CLASSB(ntohl(ic_myaddr)))
431 ic_netmask = htonl(IN_CLASSB_NET);
432 else if (IN_CLASSC(ntohl(ic_myaddr)))
433 ic_netmask = htonl(IN_CLASSC_NET);
435 printk(KERN_ERR "IP-Config: Unable to guess netmask for address %pI4\n",
439 printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
451 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
453 static struct packet_type rarp_packet_type __initdata = {
454 .type = cpu_to_be16(ETH_P_RARP),
455 .func = ic_rarp_recv,
458 static inline void __init ic_rarp_init(void)
460 dev_add_pack(&rarp_packet_type);
463 static inline void __init ic_rarp_cleanup(void)
465 dev_remove_pack(&rarp_packet_type);
469 * Process received RARP packet.
472 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
475 unsigned char *rarp_ptr;
477 unsigned char *sha, *tha; /* s for "source", t for "target" */
480 if (!net_eq(dev_net(dev), &init_net))
483 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
486 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
489 /* Basic sanity checks can be done without the lock. */
490 rarp = (struct arphdr *)skb_transport_header(skb);
492 /* If this test doesn't pass, it's not IP, or we should
495 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
498 /* If it's not a RARP reply, delete it. */
499 if (rarp->ar_op != htons(ARPOP_RREPLY))
502 /* If it's not Ethernet, delete it. */
503 if (rarp->ar_pro != htons(ETH_P_IP))
506 if (!pskb_may_pull(skb, arp_hdr_len(dev)))
509 /* OK, it is all there and looks valid, process... */
510 rarp = (struct arphdr *)skb_transport_header(skb);
511 rarp_ptr = (unsigned char *) (rarp + 1);
513 /* One reply at a time, please. */
514 spin_lock(&ic_recv_lock);
516 /* If we already have a reply, just drop the packet */
520 /* Find the ic_device that the packet arrived on */
522 while (d && d->dev != dev)
525 goto drop_unlock; /* should never happen */
527 /* Extract variable-width fields */
529 rarp_ptr += dev->addr_len;
530 memcpy(&sip, rarp_ptr, 4);
533 rarp_ptr += dev->addr_len;
534 memcpy(&tip, rarp_ptr, 4);
536 /* Discard packets which are not meant for us. */
537 if (memcmp(tha, dev->dev_addr, dev->addr_len))
540 /* Discard packets which are not from specified server. */
541 if (ic_servaddr != NONE && ic_servaddr != sip)
544 /* We have a winner! */
546 if (ic_myaddr == NONE)
549 ic_got_reply = IC_RARP;
552 /* Show's over. Nothing to see here. */
553 spin_unlock(&ic_recv_lock);
556 /* Throw the packet out. */
563 * Send RARP request packet over a single interface.
565 static void __init ic_rarp_send_if(struct ic_device *d)
567 struct net_device *dev = d->dev;
568 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
569 dev->dev_addr, dev->dev_addr);
574 * DHCP/BOOTP support.
577 #ifdef IPCONFIG_BOOTP
579 struct bootp_pkt { /* BOOTP packet format */
580 struct iphdr iph; /* IP header */
581 struct udphdr udph; /* UDP header */
582 u8 op; /* 1=request, 2=reply */
583 u8 htype; /* HW address type */
584 u8 hlen; /* HW address length */
585 u8 hops; /* Used only by gateways */
586 __be32 xid; /* Transaction ID */
587 __be16 secs; /* Seconds since we started */
588 __be16 flags; /* Just what it says */
589 __be32 client_ip; /* Client's IP address if known */
590 __be32 your_ip; /* Assigned IP address */
591 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
592 __be32 relay_ip; /* IP address of BOOTP relay */
593 u8 hw_addr[16]; /* Client's HW address */
594 u8 serv_name[64]; /* Server host name */
595 u8 boot_file[128]; /* Name of boot file */
596 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
600 #define BOOTP_REQUEST 1
601 #define BOOTP_REPLY 2
603 /* DHCP message types */
604 #define DHCPDISCOVER 1
606 #define DHCPREQUEST 3
607 #define DHCPDECLINE 4
610 #define DHCPRELEASE 7
613 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
615 static struct packet_type bootp_packet_type __initdata = {
616 .type = cpu_to_be16(ETH_P_IP),
617 .func = ic_bootp_recv,
622 * Initialize DHCP/BOOTP extension fields in the request.
625 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
630 ic_dhcp_init_options(u8 *options)
632 u8 mt = ((ic_servaddr == NONE)
633 ? DHCPDISCOVER : DHCPREQUEST);
637 #ifdef IPCONFIG_DEBUG
638 printk("DHCP: Sending message type %d\n", mt);
641 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
644 *e++ = 53; /* DHCP message type */
648 if (mt == DHCPREQUEST) {
649 *e++ = 54; /* Server ID (IP address) */
651 memcpy(e, &ic_servaddr, 4);
654 *e++ = 50; /* Requested IP address */
656 memcpy(e, &ic_myaddr, 4);
662 static const u8 ic_req_params[] = {
664 3, /* Default gateway */
667 15, /* Domain name */
670 40, /* NIS domain name */
673 *e++ = 55; /* Parameter request list */
674 *e++ = sizeof(ic_req_params);
675 memcpy(e, ic_req_params, sizeof(ic_req_params));
676 e += sizeof(ic_req_params);
678 if (ic_host_name_set) {
679 *e++ = 12; /* host-name */
680 len = strlen(utsname()->nodename);
682 memcpy(e, utsname()->nodename, len);
685 if (*vendor_class_identifier) {
686 printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
687 vendor_class_identifier);
688 *e++ = 60; /* Class-identifier */
689 len = strlen(vendor_class_identifier);
691 memcpy(e, vendor_class_identifier, len);
696 *e++ = 255; /* End of the list */
699 #endif /* IPCONFIG_DHCP */
701 static void __init ic_bootp_init_ext(u8 *e)
703 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
705 *e++ = 1; /* Subnet mask request */
708 *e++ = 3; /* Default gateway request */
711 *e++ = 5; /* Name server request */
714 *e++ = 12; /* Host name request */
717 *e++ = 40; /* NIS Domain name request */
720 *e++ = 17; /* Boot path */
724 *e++ = 57; /* set extension buffer size for reply */
726 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
729 *e++ = 255; /* End of the list */
734 * Initialize the DHCP/BOOTP mechanism.
736 static inline void __init ic_bootp_init(void)
740 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
741 ic_nameservers[i] = NONE;
743 dev_add_pack(&bootp_packet_type);
748 * DHCP/BOOTP cleanup.
750 static inline void __init ic_bootp_cleanup(void)
752 dev_remove_pack(&bootp_packet_type);
757 * Send DHCP/BOOTP request to single interface.
759 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
761 struct net_device *dev = d->dev;
766 /* Allocate packet */
767 skb = alloc_skb(sizeof(struct bootp_pkt) + LL_ALLOCATED_SPACE(dev) + 15,
771 skb_reserve(skb, LL_RESERVED_SPACE(dev));
772 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
773 memset(b, 0, sizeof(struct bootp_pkt));
775 /* Construct IP header */
776 skb_reset_network_header(skb);
780 h->tot_len = htons(sizeof(struct bootp_pkt));
781 h->frag_off = htons(IP_DF);
783 h->protocol = IPPROTO_UDP;
784 h->daddr = htonl(INADDR_BROADCAST);
785 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
787 /* Construct UDP header */
788 b->udph.source = htons(68);
789 b->udph.dest = htons(67);
790 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
791 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
793 /* Construct DHCP/BOOTP header */
794 b->op = BOOTP_REQUEST;
795 if (dev->type < 256) /* check for false types */
796 b->htype = dev->type;
797 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
798 b->htype = ARPHRD_IEEE802;
799 else if (dev->type == ARPHRD_FDDI)
800 b->htype = ARPHRD_ETHER;
802 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
803 b->htype = dev->type; /* can cause undefined behavior */
806 /* server_ip and your_ip address are both already zero per RFC2131 */
807 b->hlen = dev->addr_len;
808 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
809 b->secs = htons(jiffies_diff / HZ);
812 /* add DHCP options or BOOTP extensions */
814 if (ic_proto_enabled & IC_USE_DHCP)
815 ic_dhcp_init_options(b->exten);
818 ic_bootp_init_ext(b->exten);
820 /* Chain packet down the line... */
822 skb->protocol = htons(ETH_P_IP);
823 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
824 dev->broadcast, dev->dev_addr, skb->len) < 0 ||
825 dev_queue_xmit(skb) < 0)
831 * Copy BOOTP-supplied string if not already set.
833 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
839 memcpy(dest, src, len);
846 * Process BOOTP extensions.
848 static void __init ic_do_bootp_ext(u8 *ext)
854 #ifdef IPCONFIG_DEBUG
857 printk("DHCP/BOOTP: Got extension %d:",*ext);
858 for (c=ext+2; c<ext+2+ext[1]; c++)
864 case 1: /* Subnet mask */
865 if (ic_netmask == NONE)
866 memcpy(&ic_netmask, ext+1, 4);
868 case 3: /* Default gateway */
869 if (ic_gateway == NONE)
870 memcpy(&ic_gateway, ext+1, 4);
872 case 6: /* DNS server */
874 if (servers > CONF_NAMESERVERS_MAX)
875 servers = CONF_NAMESERVERS_MAX;
876 for (i = 0; i < servers; i++) {
877 if (ic_nameservers[i] == NONE)
878 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
881 case 12: /* Host name */
882 ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
883 ic_host_name_set = 1;
885 case 15: /* Domain name (DNS) */
886 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
888 case 17: /* Root path */
889 if (!root_server_path[0])
890 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
892 case 26: /* Interface MTU */
893 memcpy(&mtu, ext+1, sizeof(mtu));
894 ic_dev_mtu = ntohs(mtu);
896 case 40: /* NIS Domain name (_not_ DNS) */
897 ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
904 * Receive BOOTP reply.
906 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
913 if (!net_eq(dev_net(dev), &init_net))
916 /* Perform verifications before taking the lock. */
917 if (skb->pkt_type == PACKET_OTHERHOST)
920 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
923 if (!pskb_may_pull(skb,
924 sizeof(struct iphdr) +
925 sizeof(struct udphdr)))
928 b = (struct bootp_pkt *)skb_network_header(skb);
931 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
934 /* Fragments are not supported */
935 if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
937 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
942 if (skb->len < ntohs(h->tot_len))
945 if (ip_fast_csum((char *) h, h->ihl))
948 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
951 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
954 len = ntohs(b->udph.len) - sizeof(struct udphdr);
955 ext_len = len - (sizeof(*b) -
956 sizeof(struct iphdr) -
957 sizeof(struct udphdr) -
962 /* Ok the front looks good, make sure we can get at the rest. */
963 if (!pskb_may_pull(skb, skb->len))
966 b = (struct bootp_pkt *)skb_network_header(skb);
969 /* One reply at a time, please. */
970 spin_lock(&ic_recv_lock);
972 /* If we already have a reply, just drop the packet */
976 /* Find the ic_device that the packet arrived on */
978 while (d && d->dev != dev)
981 goto drop_unlock; /* should never happen */
983 /* Is it a reply to our BOOTP request? */
984 if (b->op != BOOTP_REPLY ||
987 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
993 /* Is it a reply for the device we are configuring? */
994 if (b->xid != ic_dev_xid) {
996 printk(KERN_ERR "DHCP/BOOTP: Ignoring delayed packet\n");
1000 /* Parse extensions */
1002 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1003 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1006 #ifdef IPCONFIG_DHCP
1007 if (ic_proto_enabled & IC_USE_DHCP) {
1008 __be32 server_id = NONE;
1012 while (ext < end && *ext != 0xff) {
1014 if (*opt == 0) /* Padding */
1020 case 53: /* Message type */
1024 case 54: /* Server ID (IP address) */
1026 memcpy(&server_id, opt + 2, 4);
1031 #ifdef IPCONFIG_DEBUG
1032 printk("DHCP: Got message type %d\n", mt);
1037 /* While in the process of accepting one offer,
1038 * ignore all others.
1040 if (ic_myaddr != NONE)
1043 /* Let's accept that offer. */
1044 ic_myaddr = b->your_ip;
1045 ic_servaddr = server_id;
1046 #ifdef IPCONFIG_DEBUG
1047 printk("DHCP: Offered address %pI4 by server %pI4\n",
1048 &ic_myaddr, &ic_servaddr);
1050 /* The DHCP indicated server address takes
1051 * precedence over the bootp header one if
1052 * they are different.
1054 if ((server_id != NONE) &&
1055 (b->server_ip != server_id))
1056 b->server_ip = ic_servaddr;
1060 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1067 /* Urque. Forget it*/
1073 ic_dhcp_msgtype = mt;
1076 #endif /* IPCONFIG_DHCP */
1079 while (ext < end && *ext != 0xff) {
1081 if (*opt == 0) /* Padding */
1085 ic_do_bootp_ext(opt);
1089 /* We have a winner! */
1091 ic_myaddr = b->your_ip;
1092 ic_servaddr = b->server_ip;
1093 if (ic_gateway == NONE && b->relay_ip)
1094 ic_gateway = b->relay_ip;
1095 if (ic_nameservers[0] == NONE)
1096 ic_nameservers[0] = ic_servaddr;
1097 ic_got_reply = IC_BOOTP;
1100 /* Show's over. Nothing to see here. */
1101 spin_unlock(&ic_recv_lock);
1104 /* Throw the packet out. */
1115 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1118 #ifdef IPCONFIG_DYNAMIC
1120 static int __init ic_dynamic(void)
1123 struct ic_device *d;
1124 unsigned long start_jiffies, timeout, jiff;
1125 int do_bootp = ic_proto_have_if & IC_BOOTP;
1126 int do_rarp = ic_proto_have_if & IC_RARP;
1129 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1130 * This routine gets only called when some pieces of information
1131 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1133 if (!ic_proto_enabled) {
1134 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1138 #ifdef IPCONFIG_BOOTP
1139 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1140 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1142 #ifdef IPCONFIG_RARP
1143 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1144 printk(KERN_ERR "RARP: No suitable device found.\n");
1147 if (!ic_proto_have_if)
1148 /* Error message already printed */
1154 #ifdef IPCONFIG_BOOTP
1158 #ifdef IPCONFIG_RARP
1164 * Send requests and wait, until we get an answer. This loop
1165 * seems to be a terrible waste of CPU time, but actually there is
1166 * only one process running at all, so we don't need to use any
1167 * scheduler functions.
1168 * [Actually we could now, but the nothing else running note still
1171 printk(KERN_NOTICE "Sending %s%s%s requests .",
1173 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1174 (do_bootp && do_rarp) ? " and " : "",
1175 do_rarp ? "RARP" : "");
1177 start_jiffies = jiffies;
1179 retries = CONF_SEND_RETRIES;
1180 get_random_bytes(&timeout, sizeof(timeout));
1181 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1183 /* Track the device we are configuring */
1184 ic_dev_xid = d->xid;
1186 #ifdef IPCONFIG_BOOTP
1187 if (do_bootp && (d->able & IC_BOOTP))
1188 ic_bootp_send_if(d, jiffies - start_jiffies);
1190 #ifdef IPCONFIG_RARP
1191 if (do_rarp && (d->able & IC_RARP))
1195 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1196 while (time_before(jiffies, jiff) && !ic_got_reply)
1197 schedule_timeout_uninterruptible(1);
1198 #ifdef IPCONFIG_DHCP
1199 /* DHCP isn't done until we get a DHCPACK. */
1200 if ((ic_got_reply & IC_BOOTP) &&
1201 (ic_proto_enabled & IC_USE_DHCP) &&
1202 ic_dhcp_msgtype != DHCPACK) {
1204 printk(KERN_CONT ",");
1207 #endif /* IPCONFIG_DHCP */
1210 printk(KERN_CONT " OK\n");
1218 printk(KERN_CONT " timed out!\n");
1224 timeout = timeout CONF_TIMEOUT_MULT;
1225 if (timeout > CONF_TIMEOUT_MAX)
1226 timeout = CONF_TIMEOUT_MAX;
1228 printk(KERN_CONT ".");
1231 #ifdef IPCONFIG_BOOTP
1235 #ifdef IPCONFIG_RARP
1240 if (!ic_got_reply) {
1245 printk("IP-Config: Got %s answer from %pI4, ",
1246 ((ic_got_reply & IC_RARP) ? "RARP"
1247 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1249 printk(KERN_CONT "my address is %pI4\n", &ic_myaddr);
1254 #endif /* IPCONFIG_DYNAMIC */
1256 #ifdef CONFIG_PROC_FS
1258 static int pnp_seq_show(struct seq_file *seq, void *v)
1262 if (ic_proto_used & IC_PROTO)
1263 seq_printf(seq, "#PROTO: %s\n",
1264 (ic_proto_used & IC_RARP) ? "RARP"
1265 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1267 seq_puts(seq, "#MANUAL\n");
1271 "domain %s\n", ic_domain);
1272 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1273 if (ic_nameservers[i] != NONE)
1274 seq_printf(seq, "nameserver %pI4\n",
1275 &ic_nameservers[i]);
1277 if (ic_servaddr != NONE)
1278 seq_printf(seq, "bootserver %pI4\n",
1283 static int pnp_seq_open(struct inode *indoe, struct file *file)
1285 return single_open(file, pnp_seq_show, NULL);
1288 static const struct file_operations pnp_seq_fops = {
1289 .owner = THIS_MODULE,
1290 .open = pnp_seq_open,
1292 .llseek = seq_lseek,
1293 .release = single_release,
1295 #endif /* CONFIG_PROC_FS */
1298 * Extract IP address from the parameter string if needed. Note that we
1299 * need to have root_server_addr set _before_ IPConfig gets called as it
1302 __be32 __init root_nfs_parse_addr(char *name)
1309 while (octets < 4) {
1310 while (*cp >= '0' && *cp <= '9')
1312 if (cp == cq || cp - cq > 3)
1314 if (*cp == '.' || octets == 3)
1320 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1323 addr = in_aton(name);
1324 memmove(name, cp, strlen(cp) + 1);
1331 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1333 static int __init wait_for_devices(void)
1337 for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1338 struct net_device *dev;
1342 for_each_netdev(&init_net, dev) {
1343 if (ic_is_init_dev(dev)) {
1357 * IP Autoconfig dispatcher.
1360 static int __init ip_auto_config(void)
1363 #ifdef IPCONFIG_DYNAMIC
1364 int retries = CONF_OPEN_RETRIES;
1368 #ifdef CONFIG_PROC_FS
1369 proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1370 #endif /* CONFIG_PROC_FS */
1375 DBG(("IP-Config: Entered.\n"));
1376 #ifdef IPCONFIG_DYNAMIC
1379 /* Wait for devices to appear */
1380 err = wait_for_devices();
1384 /* Setup all network devices */
1385 err = ic_open_devs();
1389 /* Give drivers a chance to settle */
1390 msleep(CONF_POST_OPEN);
1393 * If the config information is insufficient (e.g., our IP address or
1394 * IP address of the boot server is missing or we have multiple network
1395 * interfaces and no default was set), use BOOTP or RARP to get the
1398 if (ic_myaddr == NONE ||
1399 #ifdef CONFIG_ROOT_NFS
1400 (root_server_addr == NONE &&
1401 ic_servaddr == NONE &&
1402 ROOT_DEV == Root_NFS) ||
1404 ic_first_dev->next) {
1405 #ifdef IPCONFIG_DYNAMIC
1406 if (ic_dynamic() < 0) {
1410 * I don't know why, but sometimes the
1411 * eepro100 driver (at least) gets upset and
1412 * doesn't work the first time it's opened.
1413 * But then if you close it and reopen it, it
1414 * works just fine. So we need to try that at
1415 * least once before giving up.
1417 * Also, if the root will be NFS-mounted, we
1418 * have nowhere to go if DHCP fails. So we
1419 * just have to keep trying forever.
1423 #ifdef CONFIG_ROOT_NFS
1424 if (ROOT_DEV == Root_NFS) {
1426 "IP-Config: Retrying forever (NFS root)...\n");
1433 "IP-Config: Reopening network devices...\n");
1437 /* Oh, well. At least we tried. */
1438 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1441 #else /* !DYNAMIC */
1442 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1445 #endif /* IPCONFIG_DYNAMIC */
1447 /* Device selected manually or only one device -> use it */
1448 ic_dev = ic_first_dev->dev;
1451 addr = root_nfs_parse_addr(root_server_path);
1452 if (root_server_addr == NONE)
1453 root_server_addr = addr;
1456 * Use defaults wherever applicable.
1458 if (ic_defaults() < 0)
1462 * Close all network devices except the device we've
1463 * autoconfigured and set up routes.
1466 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1470 * Record which protocol was actually used.
1472 #ifdef IPCONFIG_DYNAMIC
1473 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1476 #ifndef IPCONFIG_SILENT
1478 * Clue in the operator.
1480 printk("IP-Config: Complete:\n");
1481 printk(" device=%s", ic_dev->name);
1482 printk(KERN_CONT ", addr=%pI4", &ic_myaddr);
1483 printk(KERN_CONT ", mask=%pI4", &ic_netmask);
1484 printk(KERN_CONT ", gw=%pI4", &ic_gateway);
1485 printk(KERN_CONT ",\n host=%s, domain=%s, nis-domain=%s",
1486 utsname()->nodename, ic_domain, utsname()->domainname);
1487 printk(KERN_CONT ",\n bootserver=%pI4", &ic_servaddr);
1488 printk(KERN_CONT ", rootserver=%pI4", &root_server_addr);
1489 printk(KERN_CONT ", rootpath=%s", root_server_path);
1491 printk(KERN_CONT ", mtu=%d", ic_dev_mtu);
1492 printk(KERN_CONT "\n");
1493 #endif /* !SILENT */
1498 late_initcall(ip_auto_config);
1502 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1503 * command line parameter. See Documentation/filesystems/nfs/nfsroot.txt.
1505 static int __init ic_proto_name(char *name)
1507 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1510 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1513 #ifdef CONFIG_IP_PNP_DHCP
1514 else if (!strcmp(name, "dhcp")) {
1515 ic_proto_enabled &= ~IC_RARP;
1519 #ifdef CONFIG_IP_PNP_BOOTP
1520 else if (!strcmp(name, "bootp")) {
1521 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1525 #ifdef CONFIG_IP_PNP_RARP
1526 else if (!strcmp(name, "rarp")) {
1527 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1531 #ifdef IPCONFIG_DYNAMIC
1532 else if (!strcmp(name, "both")) {
1533 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1540 static int __init ip_auto_config_setup(char *addrs)
1545 ic_set_manually = 1;
1549 * If any dhcp, bootp etc options are set, leave autoconfig on
1550 * and skip the below static IP processing.
1552 if (ic_proto_name(addrs))
1555 /* If no static IP is given, turn off autoconfig and bail. */
1557 strcmp(addrs, "off") == 0 ||
1558 strcmp(addrs, "none") == 0) {
1563 /* Parse string for static IP assignment. */
1566 if ((cp = strchr(ip, ':')))
1568 if (strlen(ip) > 0) {
1569 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1572 if ((ic_myaddr = in_aton(ip)) == ANY)
1576 if ((ic_servaddr = in_aton(ip)) == ANY)
1580 if ((ic_gateway = in_aton(ip)) == ANY)
1584 if ((ic_netmask = in_aton(ip)) == ANY)
1588 if ((dp = strchr(ip, '.'))) {
1590 strlcpy(utsname()->domainname, dp,
1591 sizeof(utsname()->domainname));
1593 strlcpy(utsname()->nodename, ip,
1594 sizeof(utsname()->nodename));
1595 ic_host_name_set = 1;
1598 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1601 if (ic_proto_name(ip) == 0 &&
1602 ic_myaddr == NONE) {
1615 static int __init nfsaddrs_config_setup(char *addrs)
1617 return ip_auto_config_setup(addrs);
1620 static int __init vendor_class_identifier_setup(char *addrs)
1622 if (strlcpy(vendor_class_identifier, addrs,
1623 sizeof(vendor_class_identifier))
1624 >= sizeof(vendor_class_identifier))
1625 printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1626 vendor_class_identifier);
1630 __setup("ip=", ip_auto_config_setup);
1631 __setup("nfsaddrs=", nfsaddrs_config_setup);
1632 __setup("dhcpclass=", vendor_class_identifier_setup);