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 <net/net_namespace.h>
59 #include <net/ipconfig.h>
60 #include <net/route.h>
62 #include <asm/uaccess.h>
63 #include <net/checksum.h>
64 #include <asm/processor.h>
66 /* Define this to allow debugging output */
70 #define DBG(x) printk x
72 #define DBG(x) do { } while(0)
75 #if defined(CONFIG_IP_PNP_DHCP)
78 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
79 #define IPCONFIG_BOOTP
81 #if defined(CONFIG_IP_PNP_RARP)
84 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
85 #define IPCONFIG_DYNAMIC
88 /* Define the friendly delay before and after opening net devices */
89 #define CONF_PRE_OPEN 500 /* Before opening: 1/2 second */
90 #define CONF_POST_OPEN 1 /* After opening: 1 second */
92 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
93 #define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */
94 #define CONF_SEND_RETRIES 6 /* Send six requests per open */
95 #define CONF_INTER_TIMEOUT (HZ/2) /* Inter-device timeout: 1/2 second */
96 #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
97 #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
98 #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
99 #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
100 #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
101 - '3' from resolv.h */
103 #define NONE __constant_htonl(INADDR_NONE)
104 #define ANY __constant_htonl(INADDR_ANY)
107 * Public IP configuration
110 /* This is used by platforms which might be able to set the ipconfig
111 * variables using firmware environment vars. If this is set, it will
112 * ignore such firmware variables.
114 int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
116 static int ic_enable __initdata = 0; /* IP config enabled? */
118 /* Protocol choice */
119 int ic_proto_enabled __initdata = 0
120 #ifdef IPCONFIG_BOOTP
123 #ifdef CONFIG_IP_PNP_DHCP
131 static int ic_host_name_set __initdata = 0; /* Host name set by us? */
133 __be32 ic_myaddr = NONE; /* My IP address */
134 static __be32 ic_netmask = NONE; /* Netmask for local subnet */
135 __be32 ic_gateway = NONE; /* Gateway IP address */
137 __be32 ic_servaddr = NONE; /* Boot server IP address */
139 __be32 root_server_addr = NONE; /* Address of NFS server */
140 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
142 /* vendor class identifier */
143 static char vendor_class_identifier[253] __initdata;
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(&init_net, 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(&init_net, 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, "%pI4", &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 %pI4\n",
394 printk("IP-Config: Guessing netmask %pI4\n", &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 __init ic_rarp_init(void)
415 dev_add_pack(&rarp_packet_type);
418 static inline void __init 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 (!net_eq(dev_net(dev), &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, arp_hdr_len(dev)))
464 /* OK, it is all there and looks valid, process... */
465 rarp = (struct arphdr *)skb_transport_header(skb);
466 rarp_ptr = (unsigned char *) (rarp + 1);
468 /* One reply at a time, please. */
469 spin_lock(&ic_recv_lock);
471 /* If we already have a reply, just drop the packet */
475 /* Find the ic_device that the packet arrived on */
477 while (d && d->dev != dev)
480 goto drop_unlock; /* should never happen */
482 /* Extract variable-width fields */
484 rarp_ptr += dev->addr_len;
485 memcpy(&sip, rarp_ptr, 4);
488 rarp_ptr += dev->addr_len;
489 memcpy(&tip, rarp_ptr, 4);
491 /* Discard packets which are not meant for us. */
492 if (memcmp(tha, dev->dev_addr, dev->addr_len))
495 /* Discard packets which are not from specified server. */
496 if (ic_servaddr != NONE && ic_servaddr != sip)
499 /* We have a winner! */
501 if (ic_myaddr == NONE)
504 ic_got_reply = IC_RARP;
507 /* Show's over. Nothing to see here. */
508 spin_unlock(&ic_recv_lock);
511 /* Throw the packet out. */
518 * Send RARP request packet over a single interface.
520 static void __init ic_rarp_send_if(struct ic_device *d)
522 struct net_device *dev = d->dev;
523 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
524 dev->dev_addr, dev->dev_addr);
529 * DHCP/BOOTP support.
532 #ifdef IPCONFIG_BOOTP
534 struct bootp_pkt { /* BOOTP packet format */
535 struct iphdr iph; /* IP header */
536 struct udphdr udph; /* UDP header */
537 u8 op; /* 1=request, 2=reply */
538 u8 htype; /* HW address type */
539 u8 hlen; /* HW address length */
540 u8 hops; /* Used only by gateways */
541 __be32 xid; /* Transaction ID */
542 __be16 secs; /* Seconds since we started */
543 __be16 flags; /* Just what it says */
544 __be32 client_ip; /* Client's IP address if known */
545 __be32 your_ip; /* Assigned IP address */
546 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
547 __be32 relay_ip; /* IP address of BOOTP relay */
548 u8 hw_addr[16]; /* Client's HW address */
549 u8 serv_name[64]; /* Server host name */
550 u8 boot_file[128]; /* Name of boot file */
551 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
555 #define BOOTP_REQUEST 1
556 #define BOOTP_REPLY 2
558 /* DHCP message types */
559 #define DHCPDISCOVER 1
561 #define DHCPREQUEST 3
562 #define DHCPDECLINE 4
565 #define DHCPRELEASE 7
568 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
570 static struct packet_type bootp_packet_type __initdata = {
571 .type = __constant_htons(ETH_P_IP),
572 .func = ic_bootp_recv,
577 * Initialize DHCP/BOOTP extension fields in the request.
580 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
585 ic_dhcp_init_options(u8 *options)
587 u8 mt = ((ic_servaddr == NONE)
588 ? DHCPDISCOVER : DHCPREQUEST);
592 #ifdef IPCONFIG_DEBUG
593 printk("DHCP: Sending message type %d\n", mt);
596 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
599 *e++ = 53; /* DHCP message type */
603 if (mt == DHCPREQUEST) {
604 *e++ = 54; /* Server ID (IP address) */
606 memcpy(e, &ic_servaddr, 4);
609 *e++ = 50; /* Requested IP address */
611 memcpy(e, &ic_myaddr, 4);
617 static const u8 ic_req_params[] = {
619 3, /* Default gateway */
622 15, /* Domain name */
624 40, /* NIS domain name */
627 *e++ = 55; /* Parameter request list */
628 *e++ = sizeof(ic_req_params);
629 memcpy(e, ic_req_params, sizeof(ic_req_params));
630 e += sizeof(ic_req_params);
632 if (*vendor_class_identifier) {
633 printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
634 vendor_class_identifier);
635 *e++ = 60; /* Class-identifier */
636 len = strlen(vendor_class_identifier);
638 memcpy(e, vendor_class_identifier, len);
643 *e++ = 255; /* End of the list */
646 #endif /* IPCONFIG_DHCP */
648 static void __init ic_bootp_init_ext(u8 *e)
650 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
652 *e++ = 1; /* Subnet mask request */
655 *e++ = 3; /* Default gateway request */
658 *e++ = 5; /* Name server request */
661 *e++ = 12; /* Host name request */
664 *e++ = 40; /* NIS Domain name request */
667 *e++ = 17; /* Boot path */
671 *e++ = 57; /* set extension buffer size for reply */
673 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
676 *e++ = 255; /* End of the list */
681 * Initialize the DHCP/BOOTP mechanism.
683 static inline void __init ic_bootp_init(void)
687 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
688 ic_nameservers[i] = NONE;
690 dev_add_pack(&bootp_packet_type);
695 * DHCP/BOOTP cleanup.
697 static inline void __init ic_bootp_cleanup(void)
699 dev_remove_pack(&bootp_packet_type);
704 * Send DHCP/BOOTP request to single interface.
706 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
708 struct net_device *dev = d->dev;
713 /* Allocate packet */
714 skb = alloc_skb(sizeof(struct bootp_pkt) + LL_ALLOCATED_SPACE(dev) + 15,
718 skb_reserve(skb, LL_RESERVED_SPACE(dev));
719 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
720 memset(b, 0, sizeof(struct bootp_pkt));
722 /* Construct IP header */
723 skb_reset_network_header(skb);
727 h->tot_len = htons(sizeof(struct bootp_pkt));
728 h->frag_off = htons(IP_DF);
730 h->protocol = IPPROTO_UDP;
731 h->daddr = htonl(INADDR_BROADCAST);
732 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
734 /* Construct UDP header */
735 b->udph.source = htons(68);
736 b->udph.dest = htons(67);
737 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
738 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
740 /* Construct DHCP/BOOTP header */
741 b->op = BOOTP_REQUEST;
742 if (dev->type < 256) /* check for false types */
743 b->htype = dev->type;
744 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
745 b->htype = ARPHRD_IEEE802;
746 else if (dev->type == ARPHRD_FDDI)
747 b->htype = ARPHRD_ETHER;
749 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
750 b->htype = dev->type; /* can cause undefined behavior */
753 /* server_ip and your_ip address are both already zero per RFC2131 */
754 b->hlen = dev->addr_len;
755 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
756 b->secs = htons(jiffies_diff / HZ);
759 /* add DHCP options or BOOTP extensions */
761 if (ic_proto_enabled & IC_USE_DHCP)
762 ic_dhcp_init_options(b->exten);
765 ic_bootp_init_ext(b->exten);
767 /* Chain packet down the line... */
769 skb->protocol = htons(ETH_P_IP);
770 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
771 dev->broadcast, dev->dev_addr, skb->len) < 0 ||
772 dev_queue_xmit(skb) < 0)
778 * Copy BOOTP-supplied string if not already set.
780 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
786 memcpy(dest, src, len);
793 * Process BOOTP extensions.
795 static void __init ic_do_bootp_ext(u8 *ext)
800 #ifdef IPCONFIG_DEBUG
803 printk("DHCP/BOOTP: Got extension %d:",*ext);
804 for (c=ext+2; c<ext+2+ext[1]; c++)
810 case 1: /* Subnet mask */
811 if (ic_netmask == NONE)
812 memcpy(&ic_netmask, ext+1, 4);
814 case 3: /* Default gateway */
815 if (ic_gateway == NONE)
816 memcpy(&ic_gateway, ext+1, 4);
818 case 6: /* DNS server */
820 if (servers > CONF_NAMESERVERS_MAX)
821 servers = CONF_NAMESERVERS_MAX;
822 for (i = 0; i < servers; i++) {
823 if (ic_nameservers[i] == NONE)
824 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
827 case 12: /* Host name */
828 ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
829 ic_host_name_set = 1;
831 case 15: /* Domain name (DNS) */
832 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
834 case 17: /* Root path */
835 if (!root_server_path[0])
836 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
838 case 40: /* NIS Domain name (_not_ DNS) */
839 ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
846 * Receive BOOTP reply.
848 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
855 if (!net_eq(dev_net(dev), &init_net))
858 /* Perform verifications before taking the lock. */
859 if (skb->pkt_type == PACKET_OTHERHOST)
862 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
865 if (!pskb_may_pull(skb,
866 sizeof(struct iphdr) +
867 sizeof(struct udphdr)))
870 b = (struct bootp_pkt *)skb_network_header(skb);
873 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
876 /* Fragments are not supported */
877 if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
879 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
884 if (skb->len < ntohs(h->tot_len))
887 if (ip_fast_csum((char *) h, h->ihl))
890 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
893 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
896 len = ntohs(b->udph.len) - sizeof(struct udphdr);
897 ext_len = len - (sizeof(*b) -
898 sizeof(struct iphdr) -
899 sizeof(struct udphdr) -
904 /* Ok the front looks good, make sure we can get at the rest. */
905 if (!pskb_may_pull(skb, skb->len))
908 b = (struct bootp_pkt *)skb_network_header(skb);
911 /* One reply at a time, please. */
912 spin_lock(&ic_recv_lock);
914 /* If we already have a reply, just drop the packet */
918 /* Find the ic_device that the packet arrived on */
920 while (d && d->dev != dev)
923 goto drop_unlock; /* should never happen */
925 /* Is it a reply to our BOOTP request? */
926 if (b->op != BOOTP_REPLY ||
929 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
935 /* Parse extensions */
937 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
938 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
942 if (ic_proto_enabled & IC_USE_DHCP) {
943 __be32 server_id = NONE;
947 while (ext < end && *ext != 0xff) {
949 if (*opt == 0) /* Padding */
955 case 53: /* Message type */
959 case 54: /* Server ID (IP address) */
961 memcpy(&server_id, opt + 2, 4);
966 #ifdef IPCONFIG_DEBUG
967 printk("DHCP: Got message type %d\n", mt);
972 /* While in the process of accepting one offer,
975 if (ic_myaddr != NONE)
978 /* Let's accept that offer. */
979 ic_myaddr = b->your_ip;
980 ic_servaddr = server_id;
981 #ifdef IPCONFIG_DEBUG
982 printk("DHCP: Offered address %pI4 by server %pI4\n",
983 &ic_myaddr, &ic_servaddr);
985 /* The DHCP indicated server address takes
986 * precedence over the bootp header one if
987 * they are different.
989 if ((server_id != NONE) &&
990 (b->server_ip != server_id))
991 b->server_ip = ic_servaddr;
995 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1002 /* Urque. Forget it*/
1008 ic_dhcp_msgtype = mt;
1011 #endif /* IPCONFIG_DHCP */
1014 while (ext < end && *ext != 0xff) {
1016 if (*opt == 0) /* Padding */
1020 ic_do_bootp_ext(opt);
1024 /* We have a winner! */
1026 ic_myaddr = b->your_ip;
1027 ic_servaddr = b->server_ip;
1028 if (ic_gateway == NONE && b->relay_ip)
1029 ic_gateway = b->relay_ip;
1030 if (ic_nameservers[0] == NONE)
1031 ic_nameservers[0] = ic_servaddr;
1032 ic_got_reply = IC_BOOTP;
1035 /* Show's over. Nothing to see here. */
1036 spin_unlock(&ic_recv_lock);
1039 /* Throw the packet out. */
1050 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1053 #ifdef IPCONFIG_DYNAMIC
1055 static int __init ic_dynamic(void)
1058 struct ic_device *d;
1059 unsigned long start_jiffies, timeout, jiff;
1060 int do_bootp = ic_proto_have_if & IC_BOOTP;
1061 int do_rarp = ic_proto_have_if & IC_RARP;
1064 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1065 * This routine gets only called when some pieces of information
1066 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1068 if (!ic_proto_enabled) {
1069 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1073 #ifdef IPCONFIG_BOOTP
1074 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1075 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1077 #ifdef IPCONFIG_RARP
1078 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1079 printk(KERN_ERR "RARP: No suitable device found.\n");
1082 if (!ic_proto_have_if)
1083 /* Error message already printed */
1089 #ifdef IPCONFIG_BOOTP
1093 #ifdef IPCONFIG_RARP
1099 * Send requests and wait, until we get an answer. This loop
1100 * seems to be a terrible waste of CPU time, but actually there is
1101 * only one process running at all, so we don't need to use any
1102 * scheduler functions.
1103 * [Actually we could now, but the nothing else running note still
1106 printk(KERN_NOTICE "Sending %s%s%s requests .",
1108 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1109 (do_bootp && do_rarp) ? " and " : "",
1110 do_rarp ? "RARP" : "");
1112 start_jiffies = jiffies;
1114 retries = CONF_SEND_RETRIES;
1115 get_random_bytes(&timeout, sizeof(timeout));
1116 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1118 #ifdef IPCONFIG_BOOTP
1119 if (do_bootp && (d->able & IC_BOOTP))
1120 ic_bootp_send_if(d, jiffies - start_jiffies);
1122 #ifdef IPCONFIG_RARP
1123 if (do_rarp && (d->able & IC_RARP))
1127 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1128 while (time_before(jiffies, jiff) && !ic_got_reply)
1129 schedule_timeout_uninterruptible(1);
1130 #ifdef IPCONFIG_DHCP
1131 /* DHCP isn't done until we get a DHCPACK. */
1132 if ((ic_got_reply & IC_BOOTP)
1133 && (ic_proto_enabled & IC_USE_DHCP)
1134 && ic_dhcp_msgtype != DHCPACK)
1140 #endif /* IPCONFIG_DHCP */
1151 printk(" timed out!\n");
1157 timeout = timeout CONF_TIMEOUT_MULT;
1158 if (timeout > CONF_TIMEOUT_MAX)
1159 timeout = CONF_TIMEOUT_MAX;
1164 #ifdef IPCONFIG_BOOTP
1168 #ifdef IPCONFIG_RARP
1173 if (!ic_got_reply) {
1178 printk("IP-Config: Got %s answer from %pI4, ",
1179 ((ic_got_reply & IC_RARP) ? "RARP"
1180 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1182 printk("my address is %pI4\n", &ic_myaddr);
1187 #endif /* IPCONFIG_DYNAMIC */
1189 #ifdef CONFIG_PROC_FS
1191 static int pnp_seq_show(struct seq_file *seq, void *v)
1195 if (ic_proto_used & IC_PROTO)
1196 seq_printf(seq, "#PROTO: %s\n",
1197 (ic_proto_used & IC_RARP) ? "RARP"
1198 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1200 seq_puts(seq, "#MANUAL\n");
1204 "domain %s\n", ic_domain);
1205 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1206 if (ic_nameservers[i] != NONE)
1207 seq_printf(seq, "nameserver %pI4\n",
1208 &ic_nameservers[i]);
1210 if (ic_servaddr != NONE)
1211 seq_printf(seq, "bootserver %pI4\n",
1216 static int pnp_seq_open(struct inode *indoe, struct file *file)
1218 return single_open(file, pnp_seq_show, NULL);
1221 static const struct file_operations pnp_seq_fops = {
1222 .owner = THIS_MODULE,
1223 .open = pnp_seq_open,
1225 .llseek = seq_lseek,
1226 .release = single_release,
1228 #endif /* CONFIG_PROC_FS */
1231 * Extract IP address from the parameter string if needed. Note that we
1232 * need to have root_server_addr set _before_ IPConfig gets called as it
1235 __be32 __init root_nfs_parse_addr(char *name)
1242 while (octets < 4) {
1243 while (*cp >= '0' && *cp <= '9')
1245 if (cp == cq || cp - cq > 3)
1247 if (*cp == '.' || octets == 3)
1253 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1256 addr = in_aton(name);
1257 memmove(name, cp, strlen(cp) + 1);
1265 * IP Autoconfig dispatcher.
1268 static int __init ip_auto_config(void)
1272 #ifdef CONFIG_PROC_FS
1273 proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1274 #endif /* CONFIG_PROC_FS */
1279 DBG(("IP-Config: Entered.\n"));
1280 #ifdef IPCONFIG_DYNAMIC
1283 /* Give hardware a chance to settle */
1284 msleep(CONF_PRE_OPEN);
1286 /* Setup all network devices */
1287 if (ic_open_devs() < 0)
1290 /* Give drivers a chance to settle */
1291 ssleep(CONF_POST_OPEN);
1294 * If the config information is insufficient (e.g., our IP address or
1295 * IP address of the boot server is missing or we have multiple network
1296 * interfaces and no default was set), use BOOTP or RARP to get the
1299 if (ic_myaddr == NONE ||
1300 #ifdef CONFIG_ROOT_NFS
1301 (root_server_addr == NONE
1302 && ic_servaddr == NONE
1303 && ROOT_DEV == Root_NFS) ||
1305 ic_first_dev->next) {
1306 #ifdef IPCONFIG_DYNAMIC
1308 int retries = CONF_OPEN_RETRIES;
1310 if (ic_dynamic() < 0) {
1314 * I don't know why, but sometimes the
1315 * eepro100 driver (at least) gets upset and
1316 * doesn't work the first time it's opened.
1317 * But then if you close it and reopen it, it
1318 * works just fine. So we need to try that at
1319 * least once before giving up.
1321 * Also, if the root will be NFS-mounted, we
1322 * have nowhere to go if DHCP fails. So we
1323 * just have to keep trying forever.
1327 #ifdef CONFIG_ROOT_NFS
1328 if (ROOT_DEV == Root_NFS) {
1330 "IP-Config: Retrying forever (NFS root)...\n");
1337 "IP-Config: Reopening network devices...\n");
1341 /* Oh, well. At least we tried. */
1342 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1345 #else /* !DYNAMIC */
1346 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1349 #endif /* IPCONFIG_DYNAMIC */
1351 /* Device selected manually or only one device -> use it */
1352 ic_dev = ic_first_dev->dev;
1355 addr = root_nfs_parse_addr(root_server_path);
1356 if (root_server_addr == NONE)
1357 root_server_addr = addr;
1360 * Use defaults whereever applicable.
1362 if (ic_defaults() < 0)
1366 * Close all network devices except the device we've
1367 * autoconfigured and set up routes.
1370 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1374 * Record which protocol was actually used.
1376 #ifdef IPCONFIG_DYNAMIC
1377 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1380 #ifndef IPCONFIG_SILENT
1382 * Clue in the operator.
1384 printk("IP-Config: Complete:");
1385 printk("\n device=%s", ic_dev->name);
1386 printk(", addr=%pI4", &ic_myaddr);
1387 printk(", mask=%pI4", &ic_netmask);
1388 printk(", gw=%pI4", &ic_gateway);
1389 printk(",\n host=%s, domain=%s, nis-domain=%s",
1390 utsname()->nodename, ic_domain, utsname()->domainname);
1391 printk(",\n bootserver=%pI4", &ic_servaddr);
1392 printk(", rootserver=%pI4", &root_server_addr);
1393 printk(", rootpath=%s", root_server_path);
1395 #endif /* !SILENT */
1400 late_initcall(ip_auto_config);
1404 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1405 * command line parameter. See Documentation/filesystems/nfsroot.txt.
1407 static int __init ic_proto_name(char *name)
1409 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1412 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1415 #ifdef CONFIG_IP_PNP_DHCP
1416 else if (!strcmp(name, "dhcp")) {
1417 ic_proto_enabled &= ~IC_RARP;
1421 #ifdef CONFIG_IP_PNP_BOOTP
1422 else if (!strcmp(name, "bootp")) {
1423 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1427 #ifdef CONFIG_IP_PNP_RARP
1428 else if (!strcmp(name, "rarp")) {
1429 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1433 #ifdef IPCONFIG_DYNAMIC
1434 else if (!strcmp(name, "both")) {
1435 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1442 static int __init ip_auto_config_setup(char *addrs)
1447 ic_set_manually = 1;
1451 * If any dhcp, bootp etc options are set, leave autoconfig on
1452 * and skip the below static IP processing.
1454 if (ic_proto_name(addrs))
1457 /* If no static IP is given, turn off autoconfig and bail. */
1459 strcmp(addrs, "off") == 0 ||
1460 strcmp(addrs, "none") == 0) {
1465 /* Parse string for static IP assignment. */
1468 if ((cp = strchr(ip, ':')))
1470 if (strlen(ip) > 0) {
1471 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1474 if ((ic_myaddr = in_aton(ip)) == ANY)
1478 if ((ic_servaddr = in_aton(ip)) == ANY)
1482 if ((ic_gateway = in_aton(ip)) == ANY)
1486 if ((ic_netmask = in_aton(ip)) == ANY)
1490 if ((dp = strchr(ip, '.'))) {
1492 strlcpy(utsname()->domainname, dp,
1493 sizeof(utsname()->domainname));
1495 strlcpy(utsname()->nodename, ip,
1496 sizeof(utsname()->nodename));
1497 ic_host_name_set = 1;
1500 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1503 if (ic_proto_name(ip) == 0 &&
1504 ic_myaddr == NONE) {
1517 static int __init nfsaddrs_config_setup(char *addrs)
1519 return ip_auto_config_setup(addrs);
1522 static int __init vendor_class_identifier_setup(char *addrs)
1524 if (strlcpy(vendor_class_identifier, addrs,
1525 sizeof(vendor_class_identifier))
1526 >= sizeof(vendor_class_identifier))
1527 printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1528 vendor_class_identifier);
1532 __setup("ip=", ip_auto_config_setup);
1533 __setup("nfsaddrs=", nfsaddrs_config_setup);
1534 __setup("dhcpclass=", vendor_class_identifier_setup);