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 static char vendor_class_identifier[253]; /* vendor class identifier */
145 /* Persistent data: */
147 static int ic_proto_used; /* Protocol used, if any */
148 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
149 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
155 /* Name of user-selected boot device */
156 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
158 /* Protocols supported by available interfaces */
159 static int ic_proto_have_if __initdata = 0;
161 #ifdef IPCONFIG_DYNAMIC
162 static DEFINE_SPINLOCK(ic_recv_lock);
163 static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
166 static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
175 struct ic_device *next;
176 struct net_device *dev;
177 unsigned short flags;
182 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
183 static struct net_device *ic_dev __initdata = NULL; /* Selected device */
185 static int __init ic_open_devs(void)
187 struct ic_device *d, **last;
188 struct net_device *dev;
189 unsigned short oflags;
191 last = &ic_first_dev;
194 /* bring loopback device up first */
195 for_each_netdev(&init_net, dev) {
196 if (!(dev->flags & IFF_LOOPBACK))
198 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
199 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
202 for_each_netdev(&init_net, dev) {
203 if (dev->flags & IFF_LOOPBACK)
205 if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
206 (!(dev->flags & IFF_LOOPBACK) &&
207 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
208 strncmp(dev->name, "dummy", 5))) {
213 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
214 if (!(dev->flags & IFF_NOARP))
216 able &= ic_proto_enabled;
217 if (ic_proto_enabled && !able)
220 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
221 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
224 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
234 get_random_bytes(&d->xid, sizeof(__be32));
237 ic_proto_have_if |= able;
238 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
239 dev->name, able, d->xid));
247 if (user_dev_name[0])
248 printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
250 printk(KERN_ERR "IP-Config: No network devices available.\n");
256 static void __init ic_close_devs(void)
258 struct ic_device *d, *next;
259 struct net_device *dev;
267 DBG(("IP-Config: Downing %s\n", dev->name));
268 dev_change_flags(dev, d->flags);
276 * Interface to various network functions.
280 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
282 sin->sin_family = AF_INET;
283 sin->sin_addr.s_addr = addr;
284 sin->sin_port = port;
287 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
291 mm_segment_t oldfs = get_fs();
293 res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
298 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
302 mm_segment_t oldfs = get_fs();
304 res = ip_rt_ioctl(cmd, (void __user *) arg);
310 * Set up interface addresses and routes.
313 static int __init ic_setup_if(void)
316 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
319 memset(&ir, 0, sizeof(ir));
320 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
321 set_sockaddr(sin, ic_myaddr, 0);
322 if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
323 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
326 set_sockaddr(sin, ic_netmask, 0);
327 if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
328 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
331 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
332 if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
333 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
339 static int __init ic_setup_routes(void)
341 /* No need to setup device routes, only the default route... */
343 if (ic_gateway != NONE) {
347 memset(&rm, 0, sizeof(rm));
348 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
349 printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
352 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
353 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
354 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
355 rm.rt_flags = RTF_UP | RTF_GATEWAY;
356 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
357 printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
366 * Fill in default values for all missing parameters.
369 static int __init ic_defaults(void)
372 * At this point we have no userspace running so need not
373 * claim locks on system_utsname
376 if (!ic_host_name_set)
377 sprintf(init_utsname()->nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
379 if (root_server_addr == NONE)
380 root_server_addr = ic_servaddr;
382 if (ic_netmask == NONE) {
383 if (IN_CLASSA(ntohl(ic_myaddr)))
384 ic_netmask = htonl(IN_CLASSA_NET);
385 else if (IN_CLASSB(ntohl(ic_myaddr)))
386 ic_netmask = htonl(IN_CLASSB_NET);
387 else if (IN_CLASSC(ntohl(ic_myaddr)))
388 ic_netmask = htonl(IN_CLASSC_NET);
390 printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
394 printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
406 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
408 static struct packet_type rarp_packet_type __initdata = {
409 .type = __constant_htons(ETH_P_RARP),
410 .func = ic_rarp_recv,
413 static inline void ic_rarp_init(void)
415 dev_add_pack(&rarp_packet_type);
418 static inline void ic_rarp_cleanup(void)
420 dev_remove_pack(&rarp_packet_type);
424 * Process received RARP packet.
427 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
430 unsigned char *rarp_ptr;
432 unsigned char *sha, *tha; /* s for "source", t for "target" */
435 if (dev->nd_net != &init_net)
438 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
441 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
444 /* Basic sanity checks can be done without the lock. */
445 rarp = (struct arphdr *)skb_transport_header(skb);
447 /* If this test doesn't pass, it's not IP, or we should
450 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
453 /* If it's not a RARP reply, delete it. */
454 if (rarp->ar_op != htons(ARPOP_RREPLY))
457 /* If it's not Ethernet, delete it. */
458 if (rarp->ar_pro != htons(ETH_P_IP))
461 if (!pskb_may_pull(skb,
462 sizeof(struct arphdr) +
463 (2 * dev->addr_len) +
467 /* OK, it is all there and looks valid, process... */
468 rarp = (struct arphdr *)skb_transport_header(skb);
469 rarp_ptr = (unsigned char *) (rarp + 1);
471 /* One reply at a time, please. */
472 spin_lock(&ic_recv_lock);
474 /* If we already have a reply, just drop the packet */
478 /* Find the ic_device that the packet arrived on */
480 while (d && d->dev != dev)
483 goto drop_unlock; /* should never happen */
485 /* Extract variable-width fields */
487 rarp_ptr += dev->addr_len;
488 memcpy(&sip, rarp_ptr, 4);
491 rarp_ptr += dev->addr_len;
492 memcpy(&tip, rarp_ptr, 4);
494 /* Discard packets which are not meant for us. */
495 if (memcmp(tha, dev->dev_addr, dev->addr_len))
498 /* Discard packets which are not from specified server. */
499 if (ic_servaddr != NONE && ic_servaddr != sip)
502 /* We have a winner! */
504 if (ic_myaddr == NONE)
507 ic_got_reply = IC_RARP;
510 /* Show's over. Nothing to see here. */
511 spin_unlock(&ic_recv_lock);
514 /* Throw the packet out. */
521 * Send RARP request packet over a single interface.
523 static void __init ic_rarp_send_if(struct ic_device *d)
525 struct net_device *dev = d->dev;
526 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
527 dev->dev_addr, dev->dev_addr);
532 * DHCP/BOOTP support.
535 #ifdef IPCONFIG_BOOTP
537 struct bootp_pkt { /* BOOTP packet format */
538 struct iphdr iph; /* IP header */
539 struct udphdr udph; /* UDP header */
540 u8 op; /* 1=request, 2=reply */
541 u8 htype; /* HW address type */
542 u8 hlen; /* HW address length */
543 u8 hops; /* Used only by gateways */
544 __be32 xid; /* Transaction ID */
545 __be16 secs; /* Seconds since we started */
546 __be16 flags; /* Just what it says */
547 __be32 client_ip; /* Client's IP address if known */
548 __be32 your_ip; /* Assigned IP address */
549 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
550 __be32 relay_ip; /* IP address of BOOTP relay */
551 u8 hw_addr[16]; /* Client's HW address */
552 u8 serv_name[64]; /* Server host name */
553 u8 boot_file[128]; /* Name of boot file */
554 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
558 #define BOOTP_REQUEST 1
559 #define BOOTP_REPLY 2
561 /* DHCP message types */
562 #define DHCPDISCOVER 1
564 #define DHCPREQUEST 3
565 #define DHCPDECLINE 4
568 #define DHCPRELEASE 7
571 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
573 static struct packet_type bootp_packet_type __initdata = {
574 .type = __constant_htons(ETH_P_IP),
575 .func = ic_bootp_recv,
580 * Initialize DHCP/BOOTP extension fields in the request.
583 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
588 ic_dhcp_init_options(u8 *options)
590 u8 mt = ((ic_servaddr == NONE)
591 ? DHCPDISCOVER : DHCPREQUEST);
595 #ifdef IPCONFIG_DEBUG
596 printk("DHCP: Sending message type %d\n", mt);
599 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
602 *e++ = 53; /* DHCP message type */
606 if (mt == DHCPREQUEST) {
607 *e++ = 54; /* Server ID (IP address) */
609 memcpy(e, &ic_servaddr, 4);
612 *e++ = 50; /* Requested IP address */
614 memcpy(e, &ic_myaddr, 4);
620 static const u8 ic_req_params[] = {
622 3, /* Default gateway */
625 15, /* Domain name */
627 40, /* NIS domain name */
630 *e++ = 55; /* Parameter request list */
631 *e++ = sizeof(ic_req_params);
632 memcpy(e, ic_req_params, sizeof(ic_req_params));
633 e += sizeof(ic_req_params);
635 if (*vendor_class_identifier) {
636 printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
637 vendor_class_identifier);
638 *e++ = 60; /* Class-identifier */
639 len = strlen(vendor_class_identifier);
641 memcpy(e, vendor_class_identifier, len);
646 *e++ = 255; /* End of the list */
649 #endif /* IPCONFIG_DHCP */
651 static void __init ic_bootp_init_ext(u8 *e)
653 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
655 *e++ = 1; /* Subnet mask request */
658 *e++ = 3; /* Default gateway request */
661 *e++ = 5; /* Name server request */
664 *e++ = 12; /* Host name request */
667 *e++ = 40; /* NIS Domain name request */
670 *e++ = 17; /* Boot path */
674 *e++ = 57; /* set extension buffer size for reply */
676 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
679 *e++ = 255; /* End of the list */
684 * Initialize the DHCP/BOOTP mechanism.
686 static inline void ic_bootp_init(void)
690 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
691 ic_nameservers[i] = NONE;
693 dev_add_pack(&bootp_packet_type);
698 * DHCP/BOOTP cleanup.
700 static inline void ic_bootp_cleanup(void)
702 dev_remove_pack(&bootp_packet_type);
707 * Send DHCP/BOOTP request to single interface.
709 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
711 struct net_device *dev = d->dev;
714 int hh_len = LL_RESERVED_SPACE(dev);
717 /* Allocate packet */
718 skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
721 skb_reserve(skb, hh_len);
722 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
723 memset(b, 0, sizeof(struct bootp_pkt));
725 /* Construct IP header */
726 skb_reset_network_header(skb);
730 h->tot_len = htons(sizeof(struct bootp_pkt));
731 h->frag_off = htons(IP_DF);
733 h->protocol = IPPROTO_UDP;
734 h->daddr = htonl(INADDR_BROADCAST);
735 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
737 /* Construct UDP header */
738 b->udph.source = htons(68);
739 b->udph.dest = htons(67);
740 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
741 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
743 /* Construct DHCP/BOOTP header */
744 b->op = BOOTP_REQUEST;
745 if (dev->type < 256) /* check for false types */
746 b->htype = dev->type;
747 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
748 b->htype = ARPHRD_IEEE802;
749 else if (dev->type == ARPHRD_FDDI)
750 b->htype = ARPHRD_ETHER;
752 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
753 b->htype = dev->type; /* can cause undefined behavior */
755 b->hlen = dev->addr_len;
758 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
759 b->secs = htons(jiffies_diff / HZ);
762 /* add DHCP options or BOOTP extensions */
764 if (ic_proto_enabled & IC_USE_DHCP)
765 ic_dhcp_init_options(b->exten);
768 ic_bootp_init_ext(b->exten);
770 /* Chain packet down the line... */
772 skb->protocol = htons(ETH_P_IP);
773 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
774 dev->broadcast, dev->dev_addr, skb->len) < 0 ||
775 dev_queue_xmit(skb) < 0)
781 * Copy BOOTP-supplied string if not already set.
783 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
789 memcpy(dest, src, len);
796 * Process BOOTP extensions.
798 static void __init ic_do_bootp_ext(u8 *ext)
803 #ifdef IPCONFIG_DEBUG
806 printk("DHCP/BOOTP: Got extension %d:",*ext);
807 for (c=ext+2; c<ext+2+ext[1]; c++)
813 case 1: /* Subnet mask */
814 if (ic_netmask == NONE)
815 memcpy(&ic_netmask, ext+1, 4);
817 case 3: /* Default gateway */
818 if (ic_gateway == NONE)
819 memcpy(&ic_gateway, ext+1, 4);
821 case 6: /* DNS server */
823 if (servers > CONF_NAMESERVERS_MAX)
824 servers = CONF_NAMESERVERS_MAX;
825 for (i = 0; i < servers; i++) {
826 if (ic_nameservers[i] == NONE)
827 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
830 case 12: /* Host name */
831 ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
832 ic_host_name_set = 1;
834 case 15: /* Domain name (DNS) */
835 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
837 case 17: /* Root path */
838 if (!root_server_path[0])
839 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
841 case 40: /* NIS Domain name (_not_ DNS) */
842 ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
849 * Receive BOOTP reply.
851 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
858 if (dev->nd_net != &init_net)
861 /* Perform verifications before taking the lock. */
862 if (skb->pkt_type == PACKET_OTHERHOST)
865 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
868 if (!pskb_may_pull(skb,
869 sizeof(struct iphdr) +
870 sizeof(struct udphdr)))
873 b = (struct bootp_pkt *)skb_network_header(skb);
876 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
879 /* Fragments are not supported */
880 if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
882 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
887 if (skb->len < ntohs(h->tot_len))
890 if (ip_fast_csum((char *) h, h->ihl))
893 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
896 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
899 len = ntohs(b->udph.len) - sizeof(struct udphdr);
900 ext_len = len - (sizeof(*b) -
901 sizeof(struct iphdr) -
902 sizeof(struct udphdr) -
907 /* Ok the front looks good, make sure we can get at the rest. */
908 if (!pskb_may_pull(skb, skb->len))
911 b = (struct bootp_pkt *)skb_network_header(skb);
914 /* One reply at a time, please. */
915 spin_lock(&ic_recv_lock);
917 /* If we already have a reply, just drop the packet */
921 /* Find the ic_device that the packet arrived on */
923 while (d && d->dev != dev)
926 goto drop_unlock; /* should never happen */
928 /* Is it a reply to our BOOTP request? */
929 if (b->op != BOOTP_REPLY ||
932 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
938 /* Parse extensions */
940 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
941 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
945 if (ic_proto_enabled & IC_USE_DHCP) {
946 __be32 server_id = NONE;
950 while (ext < end && *ext != 0xff) {
952 if (*opt == 0) /* Padding */
958 case 53: /* Message type */
962 case 54: /* Server ID (IP address) */
964 memcpy(&server_id, opt + 2, 4);
969 #ifdef IPCONFIG_DEBUG
970 printk("DHCP: Got message type %d\n", mt);
975 /* While in the process of accepting one offer,
978 if (ic_myaddr != NONE)
981 /* Let's accept that offer. */
982 ic_myaddr = b->your_ip;
983 ic_servaddr = server_id;
984 #ifdef IPCONFIG_DEBUG
985 printk("DHCP: Offered address %u.%u.%u.%u",
987 printk(" by server %u.%u.%u.%u\n",
988 NIPQUAD(ic_servaddr));
990 /* The DHCP indicated server address takes
991 * precedence over the bootp header one if
992 * they are different.
994 if ((server_id != NONE) &&
995 (b->server_ip != server_id))
996 b->server_ip = ic_servaddr;
1000 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1007 /* Urque. Forget it*/
1013 ic_dhcp_msgtype = mt;
1016 #endif /* IPCONFIG_DHCP */
1019 while (ext < end && *ext != 0xff) {
1021 if (*opt == 0) /* Padding */
1025 ic_do_bootp_ext(opt);
1029 /* We have a winner! */
1031 ic_myaddr = b->your_ip;
1032 ic_servaddr = b->server_ip;
1033 if (ic_gateway == NONE && b->relay_ip)
1034 ic_gateway = b->relay_ip;
1035 if (ic_nameservers[0] == NONE)
1036 ic_nameservers[0] = ic_servaddr;
1037 ic_got_reply = IC_BOOTP;
1040 /* Show's over. Nothing to see here. */
1041 spin_unlock(&ic_recv_lock);
1044 /* Throw the packet out. */
1055 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1058 #ifdef IPCONFIG_DYNAMIC
1060 static int __init ic_dynamic(void)
1063 struct ic_device *d;
1064 unsigned long start_jiffies, timeout, jiff;
1065 int do_bootp = ic_proto_have_if & IC_BOOTP;
1066 int do_rarp = ic_proto_have_if & IC_RARP;
1069 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1070 * This routine gets only called when some pieces of information
1071 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1073 if (!ic_proto_enabled) {
1074 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1078 #ifdef IPCONFIG_BOOTP
1079 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1080 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1082 #ifdef IPCONFIG_RARP
1083 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1084 printk(KERN_ERR "RARP: No suitable device found.\n");
1087 if (!ic_proto_have_if)
1088 /* Error message already printed */
1094 #ifdef IPCONFIG_BOOTP
1098 #ifdef IPCONFIG_RARP
1104 * Send requests and wait, until we get an answer. This loop
1105 * seems to be a terrible waste of CPU time, but actually there is
1106 * only one process running at all, so we don't need to use any
1107 * scheduler functions.
1108 * [Actually we could now, but the nothing else running note still
1111 printk(KERN_NOTICE "Sending %s%s%s requests .",
1113 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1114 (do_bootp && do_rarp) ? " and " : "",
1115 do_rarp ? "RARP" : "");
1117 start_jiffies = jiffies;
1119 retries = CONF_SEND_RETRIES;
1120 get_random_bytes(&timeout, sizeof(timeout));
1121 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1123 #ifdef IPCONFIG_BOOTP
1124 if (do_bootp && (d->able & IC_BOOTP))
1125 ic_bootp_send_if(d, jiffies - start_jiffies);
1127 #ifdef IPCONFIG_RARP
1128 if (do_rarp && (d->able & IC_RARP))
1132 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1133 while (time_before(jiffies, jiff) && !ic_got_reply)
1134 schedule_timeout_uninterruptible(1);
1135 #ifdef IPCONFIG_DHCP
1136 /* DHCP isn't done until we get a DHCPACK. */
1137 if ((ic_got_reply & IC_BOOTP)
1138 && (ic_proto_enabled & IC_USE_DHCP)
1139 && ic_dhcp_msgtype != DHCPACK)
1145 #endif /* IPCONFIG_DHCP */
1156 printk(" timed out!\n");
1162 timeout = timeout CONF_TIMEOUT_MULT;
1163 if (timeout > CONF_TIMEOUT_MAX)
1164 timeout = CONF_TIMEOUT_MAX;
1169 #ifdef IPCONFIG_BOOTP
1173 #ifdef IPCONFIG_RARP
1178 if (!ic_got_reply) {
1183 printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1184 ((ic_got_reply & IC_RARP) ? "RARP"
1185 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1186 NIPQUAD(ic_servaddr));
1187 printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1192 #endif /* IPCONFIG_DYNAMIC */
1194 #ifdef CONFIG_PROC_FS
1196 static int pnp_seq_show(struct seq_file *seq, void *v)
1200 if (ic_proto_used & IC_PROTO)
1201 seq_printf(seq, "#PROTO: %s\n",
1202 (ic_proto_used & IC_RARP) ? "RARP"
1203 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1205 seq_puts(seq, "#MANUAL\n");
1209 "domain %s\n", ic_domain);
1210 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1211 if (ic_nameservers[i] != NONE)
1213 "nameserver %u.%u.%u.%u\n",
1214 NIPQUAD(ic_nameservers[i]));
1216 if (ic_servaddr != NONE)
1218 "bootserver %u.%u.%u.%u\n",
1219 NIPQUAD(ic_servaddr));
1223 static int pnp_seq_open(struct inode *indoe, struct file *file)
1225 return single_open(file, pnp_seq_show, NULL);
1228 static const struct file_operations pnp_seq_fops = {
1229 .owner = THIS_MODULE,
1230 .open = pnp_seq_open,
1232 .llseek = seq_lseek,
1233 .release = single_release,
1235 #endif /* CONFIG_PROC_FS */
1238 * Extract IP address from the parameter string if needed. Note that we
1239 * need to have root_server_addr set _before_ IPConfig gets called as it
1242 __be32 __init root_nfs_parse_addr(char *name)
1249 while (octets < 4) {
1250 while (*cp >= '0' && *cp <= '9')
1252 if (cp == cq || cp - cq > 3)
1254 if (*cp == '.' || octets == 3)
1260 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1263 addr = in_aton(name);
1264 memmove(name, cp, strlen(cp) + 1);
1272 * IP Autoconfig dispatcher.
1275 static int __init ip_auto_config(void)
1279 #ifdef CONFIG_PROC_FS
1280 proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1281 #endif /* CONFIG_PROC_FS */
1286 DBG(("IP-Config: Entered.\n"));
1287 #ifdef IPCONFIG_DYNAMIC
1290 /* Give hardware a chance to settle */
1291 msleep(CONF_PRE_OPEN);
1293 /* Setup all network devices */
1294 if (ic_open_devs() < 0)
1297 /* Give drivers a chance to settle */
1298 ssleep(CONF_POST_OPEN);
1301 * If the config information is insufficient (e.g., our IP address or
1302 * IP address of the boot server is missing or we have multiple network
1303 * interfaces and no default was set), use BOOTP or RARP to get the
1306 if (ic_myaddr == NONE ||
1307 #ifdef CONFIG_ROOT_NFS
1308 (root_server_addr == NONE
1309 && ic_servaddr == NONE
1310 && ROOT_DEV == Root_NFS) ||
1312 ic_first_dev->next) {
1313 #ifdef IPCONFIG_DYNAMIC
1315 int retries = CONF_OPEN_RETRIES;
1317 if (ic_dynamic() < 0) {
1321 * I don't know why, but sometimes the
1322 * eepro100 driver (at least) gets upset and
1323 * doesn't work the first time it's opened.
1324 * But then if you close it and reopen it, it
1325 * works just fine. So we need to try that at
1326 * least once before giving up.
1328 * Also, if the root will be NFS-mounted, we
1329 * have nowhere to go if DHCP fails. So we
1330 * just have to keep trying forever.
1334 #ifdef CONFIG_ROOT_NFS
1335 if (ROOT_DEV == Root_NFS) {
1337 "IP-Config: Retrying forever (NFS root)...\n");
1344 "IP-Config: Reopening network devices...\n");
1348 /* Oh, well. At least we tried. */
1349 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1352 #else /* !DYNAMIC */
1353 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1356 #endif /* IPCONFIG_DYNAMIC */
1358 /* Device selected manually or only one device -> use it */
1359 ic_dev = ic_first_dev->dev;
1362 addr = root_nfs_parse_addr(root_server_path);
1363 if (root_server_addr == NONE)
1364 root_server_addr = addr;
1367 * Use defaults whereever applicable.
1369 if (ic_defaults() < 0)
1373 * Close all network devices except the device we've
1374 * autoconfigured and set up routes.
1377 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1381 * Record which protocol was actually used.
1383 #ifdef IPCONFIG_DYNAMIC
1384 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1387 #ifndef IPCONFIG_SILENT
1389 * Clue in the operator.
1391 printk("IP-Config: Complete:");
1392 printk("\n device=%s", ic_dev->name);
1393 printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1394 printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1395 printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1396 printk(",\n host=%s, domain=%s, nis-domain=%s",
1397 utsname()->nodename, ic_domain, utsname()->domainname);
1398 printk(",\n bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1399 printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1400 printk(", rootpath=%s", root_server_path);
1402 #endif /* !SILENT */
1407 late_initcall(ip_auto_config);
1411 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1412 * command line parameter. See Documentation/nfsroot.txt.
1414 static int __init ic_proto_name(char *name)
1416 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1419 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1422 #ifdef CONFIG_IP_PNP_DHCP
1423 else if (!strcmp(name, "dhcp")) {
1424 ic_proto_enabled &= ~IC_RARP;
1428 #ifdef CONFIG_IP_PNP_BOOTP
1429 else if (!strcmp(name, "bootp")) {
1430 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1434 #ifdef CONFIG_IP_PNP_RARP
1435 else if (!strcmp(name, "rarp")) {
1436 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1440 #ifdef IPCONFIG_DYNAMIC
1441 else if (!strcmp(name, "both")) {
1442 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1449 static int __init ip_auto_config_setup(char *addrs)
1454 ic_set_manually = 1;
1458 * If any dhcp, bootp etc options are set, leave autoconfig on
1459 * and skip the below static IP processing.
1461 if (ic_proto_name(addrs))
1464 /* If no static IP is given, turn off autoconfig and bail. */
1466 strcmp(addrs, "off") == 0 ||
1467 strcmp(addrs, "none") == 0) {
1472 /* Parse string for static IP assignment. */
1475 if ((cp = strchr(ip, ':')))
1477 if (strlen(ip) > 0) {
1478 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1481 if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1485 if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1489 if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1493 if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1497 if ((dp = strchr(ip, '.'))) {
1499 strlcpy(utsname()->domainname, dp,
1500 sizeof(utsname()->domainname));
1502 strlcpy(utsname()->nodename, ip,
1503 sizeof(utsname()->nodename));
1504 ic_host_name_set = 1;
1507 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1510 if (ic_proto_name(ip) == 0 &&
1511 ic_myaddr == NONE) {
1524 static int __init nfsaddrs_config_setup(char *addrs)
1526 return ip_auto_config_setup(addrs);
1529 static int __init vendor_class_identifier_setup(char *addrs)
1531 if (strlcpy(vendor_class_identifier, addrs,
1532 sizeof(vendor_class_identifier))
1533 >= sizeof(vendor_class_identifier))
1534 printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1535 vendor_class_identifier);
1539 __setup("ip=", ip_auto_config_setup);
1540 __setup("nfsaddrs=", nfsaddrs_config_setup);
1541 __setup("dhcpclass=", vendor_class_identifier_setup);