2 * Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
3 * user-supplied information to configure own IP address and routes.
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.
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.
22 * Ported DHCP support from 2.2.16 to 2.4.0-test4
25 * Merged changes from 2.2.19 into 2.4.3
28 * Multiple Nameservers in /proc/net/pnp
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 <linux/export.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_POST_OPEN 10 /* After opening: 10 msecs */
92 #define CONF_CARRIER_TIMEOUT 120000 /* Wait for carrier timeout */
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 cpu_to_be32(INADDR_NONE)
106 #define ANY cpu_to_be32(INADDR_ANY)
109 * Public IP configuration
112 /* This is used by platforms which might be able to set the ipconfig
113 * variables using firmware environment vars. If this is set, it will
114 * ignore such firmware variables.
116 int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
118 static int ic_enable __initdata = 0; /* IP config enabled? */
120 /* Protocol choice */
121 int ic_proto_enabled __initdata = 0
122 #ifdef IPCONFIG_BOOTP
125 #ifdef CONFIG_IP_PNP_DHCP
133 static int ic_host_name_set __initdata = 0; /* Host name set by us? */
135 __be32 ic_myaddr = NONE; /* My IP address */
136 static __be32 ic_netmask = NONE; /* Netmask for local subnet */
137 __be32 ic_gateway = NONE; /* Gateway IP address */
139 __be32 ic_servaddr = NONE; /* Boot server IP address */
141 __be32 root_server_addr = NONE; /* Address of NFS server */
142 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
144 __be32 ic_dev_xid; /* Device under configuration */
146 /* vendor class identifier */
147 static char vendor_class_identifier[253] __initdata;
149 /* Persistent data: */
151 static int ic_proto_used; /* Protocol used, if any */
152 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
153 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
159 /* Name of user-selected boot device */
160 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
162 /* Protocols supported by available interfaces */
163 static int ic_proto_have_if __initdata = 0;
165 /* MTU for boot device */
166 static int ic_dev_mtu __initdata = 0;
168 #ifdef IPCONFIG_DYNAMIC
169 static DEFINE_SPINLOCK(ic_recv_lock);
170 static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
173 static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
182 struct ic_device *next;
183 struct net_device *dev;
184 unsigned short flags;
189 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
190 static struct net_device *ic_dev __initdata = NULL; /* Selected device */
192 static bool __init ic_is_init_dev(struct net_device *dev)
194 if (dev->flags & IFF_LOOPBACK)
196 return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
197 (!(dev->flags & IFF_LOOPBACK) &&
198 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
199 strncmp(dev->name, "dummy", 5));
202 static int __init ic_open_devs(void)
204 struct ic_device *d, **last;
205 struct net_device *dev;
206 unsigned short oflags;
209 last = &ic_first_dev;
212 /* bring loopback device up first */
213 for_each_netdev(&init_net, dev) {
214 if (!(dev->flags & IFF_LOOPBACK))
216 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
217 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
220 for_each_netdev(&init_net, dev) {
221 if (ic_is_init_dev(dev)) {
226 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
227 if (!(dev->flags & IFF_NOARP))
229 able &= ic_proto_enabled;
230 if (ic_proto_enabled && !able)
233 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
234 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
237 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
247 get_random_bytes(&d->xid, sizeof(__be32));
250 ic_proto_have_if |= able;
251 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
252 dev->name, able, d->xid));
256 /* no point in waiting if we could not bring up at least one device */
260 /* wait for a carrier on at least one device */
262 while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
263 for_each_netdev(&init_net, dev)
264 if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
275 if (user_dev_name[0])
276 printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
278 printk(KERN_ERR "IP-Config: No network devices available.\n");
284 static void __init ic_close_devs(void)
286 struct ic_device *d, *next;
287 struct net_device *dev;
295 DBG(("IP-Config: Downing %s\n", dev->name));
296 dev_change_flags(dev, d->flags);
304 * Interface to various network functions.
308 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
310 sin->sin_family = AF_INET;
311 sin->sin_addr.s_addr = addr;
312 sin->sin_port = port;
315 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
319 mm_segment_t oldfs = get_fs();
321 res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
326 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
330 mm_segment_t oldfs = get_fs();
332 res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
337 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
341 mm_segment_t oldfs = get_fs();
343 res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
349 * Set up interface addresses and routes.
352 static int __init ic_setup_if(void)
355 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
358 memset(&ir, 0, sizeof(ir));
359 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
360 set_sockaddr(sin, ic_myaddr, 0);
361 if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
362 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
365 set_sockaddr(sin, ic_netmask, 0);
366 if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
367 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
370 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
371 if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
372 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
375 /* Handle the case where we need non-standard MTU on the boot link (a network
376 * using jumbo frames, for instance). If we can't set the mtu, don't error
377 * out, we'll try to muddle along.
379 if (ic_dev_mtu != 0) {
380 strcpy(ir.ifr_name, ic_dev->name);
381 ir.ifr_mtu = ic_dev_mtu;
382 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
383 printk(KERN_ERR "IP-Config: Unable to set interface mtu to %d (%d).\n",
389 static int __init ic_setup_routes(void)
391 /* No need to setup device routes, only the default route... */
393 if (ic_gateway != NONE) {
397 memset(&rm, 0, sizeof(rm));
398 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
399 printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
402 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
403 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
404 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
405 rm.rt_flags = RTF_UP | RTF_GATEWAY;
406 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
407 printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
416 * Fill in default values for all missing parameters.
419 static int __init ic_defaults(void)
422 * At this point we have no userspace running so need not
423 * claim locks on system_utsname
426 if (!ic_host_name_set)
427 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
429 if (root_server_addr == NONE)
430 root_server_addr = ic_servaddr;
432 if (ic_netmask == NONE) {
433 if (IN_CLASSA(ntohl(ic_myaddr)))
434 ic_netmask = htonl(IN_CLASSA_NET);
435 else if (IN_CLASSB(ntohl(ic_myaddr)))
436 ic_netmask = htonl(IN_CLASSB_NET);
437 else if (IN_CLASSC(ntohl(ic_myaddr)))
438 ic_netmask = htonl(IN_CLASSC_NET);
440 printk(KERN_ERR "IP-Config: Unable to guess netmask for address %pI4\n",
444 printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
456 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
458 static struct packet_type rarp_packet_type __initdata = {
459 .type = cpu_to_be16(ETH_P_RARP),
460 .func = ic_rarp_recv,
463 static inline void __init ic_rarp_init(void)
465 dev_add_pack(&rarp_packet_type);
468 static inline void __init ic_rarp_cleanup(void)
470 dev_remove_pack(&rarp_packet_type);
474 * Process received RARP packet.
477 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
480 unsigned char *rarp_ptr;
482 unsigned char *sha, *tha; /* s for "source", t for "target" */
485 if (!net_eq(dev_net(dev), &init_net))
488 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
491 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
494 /* Basic sanity checks can be done without the lock. */
495 rarp = (struct arphdr *)skb_transport_header(skb);
497 /* If this test doesn't pass, it's not IP, or we should
500 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
503 /* If it's not a RARP reply, delete it. */
504 if (rarp->ar_op != htons(ARPOP_RREPLY))
507 /* If it's not Ethernet, delete it. */
508 if (rarp->ar_pro != htons(ETH_P_IP))
511 if (!pskb_may_pull(skb, arp_hdr_len(dev)))
514 /* OK, it is all there and looks valid, process... */
515 rarp = (struct arphdr *)skb_transport_header(skb);
516 rarp_ptr = (unsigned char *) (rarp + 1);
518 /* One reply at a time, please. */
519 spin_lock(&ic_recv_lock);
521 /* If we already have a reply, just drop the packet */
525 /* Find the ic_device that the packet arrived on */
527 while (d && d->dev != dev)
530 goto drop_unlock; /* should never happen */
532 /* Extract variable-width fields */
534 rarp_ptr += dev->addr_len;
535 memcpy(&sip, rarp_ptr, 4);
538 rarp_ptr += dev->addr_len;
539 memcpy(&tip, rarp_ptr, 4);
541 /* Discard packets which are not meant for us. */
542 if (memcmp(tha, dev->dev_addr, dev->addr_len))
545 /* Discard packets which are not from specified server. */
546 if (ic_servaddr != NONE && ic_servaddr != sip)
549 /* We have a winner! */
551 if (ic_myaddr == NONE)
554 ic_got_reply = IC_RARP;
557 /* Show's over. Nothing to see here. */
558 spin_unlock(&ic_recv_lock);
561 /* Throw the packet out. */
568 * Send RARP request packet over a single interface.
570 static void __init ic_rarp_send_if(struct ic_device *d)
572 struct net_device *dev = d->dev;
573 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
574 dev->dev_addr, dev->dev_addr);
579 * DHCP/BOOTP support.
582 #ifdef IPCONFIG_BOOTP
584 struct bootp_pkt { /* BOOTP packet format */
585 struct iphdr iph; /* IP header */
586 struct udphdr udph; /* UDP header */
587 u8 op; /* 1=request, 2=reply */
588 u8 htype; /* HW address type */
589 u8 hlen; /* HW address length */
590 u8 hops; /* Used only by gateways */
591 __be32 xid; /* Transaction ID */
592 __be16 secs; /* Seconds since we started */
593 __be16 flags; /* Just what it says */
594 __be32 client_ip; /* Client's IP address if known */
595 __be32 your_ip; /* Assigned IP address */
596 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
597 __be32 relay_ip; /* IP address of BOOTP relay */
598 u8 hw_addr[16]; /* Client's HW address */
599 u8 serv_name[64]; /* Server host name */
600 u8 boot_file[128]; /* Name of boot file */
601 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
605 #define BOOTP_REQUEST 1
606 #define BOOTP_REPLY 2
608 /* DHCP message types */
609 #define DHCPDISCOVER 1
611 #define DHCPREQUEST 3
612 #define DHCPDECLINE 4
615 #define DHCPRELEASE 7
618 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
620 static struct packet_type bootp_packet_type __initdata = {
621 .type = cpu_to_be16(ETH_P_IP),
622 .func = ic_bootp_recv,
627 * Initialize DHCP/BOOTP extension fields in the request.
630 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
635 ic_dhcp_init_options(u8 *options)
637 u8 mt = ((ic_servaddr == NONE)
638 ? DHCPDISCOVER : DHCPREQUEST);
642 #ifdef IPCONFIG_DEBUG
643 printk("DHCP: Sending message type %d\n", mt);
646 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
649 *e++ = 53; /* DHCP message type */
653 if (mt == DHCPREQUEST) {
654 *e++ = 54; /* Server ID (IP address) */
656 memcpy(e, &ic_servaddr, 4);
659 *e++ = 50; /* Requested IP address */
661 memcpy(e, &ic_myaddr, 4);
667 static const u8 ic_req_params[] = {
669 3, /* Default gateway */
672 15, /* Domain name */
675 40, /* NIS domain name */
678 *e++ = 55; /* Parameter request list */
679 *e++ = sizeof(ic_req_params);
680 memcpy(e, ic_req_params, sizeof(ic_req_params));
681 e += sizeof(ic_req_params);
683 if (ic_host_name_set) {
684 *e++ = 12; /* host-name */
685 len = strlen(utsname()->nodename);
687 memcpy(e, utsname()->nodename, len);
690 if (*vendor_class_identifier) {
691 printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
692 vendor_class_identifier);
693 *e++ = 60; /* Class-identifier */
694 len = strlen(vendor_class_identifier);
696 memcpy(e, vendor_class_identifier, len);
701 *e++ = 255; /* End of the list */
704 #endif /* IPCONFIG_DHCP */
706 static void __init ic_bootp_init_ext(u8 *e)
708 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
710 *e++ = 1; /* Subnet mask request */
713 *e++ = 3; /* Default gateway request */
716 *e++ = 5; /* Name server request */
719 *e++ = 12; /* Host name request */
722 *e++ = 40; /* NIS Domain name request */
725 *e++ = 17; /* Boot path */
729 *e++ = 57; /* set extension buffer size for reply */
731 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
734 *e++ = 255; /* End of the list */
739 * Initialize the DHCP/BOOTP mechanism.
741 static inline void __init ic_bootp_init(void)
745 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
746 ic_nameservers[i] = NONE;
748 dev_add_pack(&bootp_packet_type);
753 * DHCP/BOOTP cleanup.
755 static inline void __init ic_bootp_cleanup(void)
757 dev_remove_pack(&bootp_packet_type);
762 * Send DHCP/BOOTP request to single interface.
764 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
766 struct net_device *dev = d->dev;
770 int hlen = LL_RESERVED_SPACE(dev);
771 int tlen = dev->needed_tailroom;
773 /* Allocate packet */
774 skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
778 skb_reserve(skb, hlen);
779 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
780 memset(b, 0, sizeof(struct bootp_pkt));
782 /* Construct IP header */
783 skb_reset_network_header(skb);
787 h->tot_len = htons(sizeof(struct bootp_pkt));
788 h->frag_off = htons(IP_DF);
790 h->protocol = IPPROTO_UDP;
791 h->daddr = htonl(INADDR_BROADCAST);
792 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
794 /* Construct UDP header */
795 b->udph.source = htons(68);
796 b->udph.dest = htons(67);
797 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
798 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
800 /* Construct DHCP/BOOTP header */
801 b->op = BOOTP_REQUEST;
802 if (dev->type < 256) /* check for false types */
803 b->htype = dev->type;
804 else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
805 b->htype = ARPHRD_IEEE802;
806 else if (dev->type == ARPHRD_FDDI)
807 b->htype = ARPHRD_ETHER;
809 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
810 b->htype = dev->type; /* can cause undefined behavior */
813 /* server_ip and your_ip address are both already zero per RFC2131 */
814 b->hlen = dev->addr_len;
815 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
816 b->secs = htons(jiffies_diff / HZ);
819 /* add DHCP options or BOOTP extensions */
821 if (ic_proto_enabled & IC_USE_DHCP)
822 ic_dhcp_init_options(b->exten);
825 ic_bootp_init_ext(b->exten);
827 /* Chain packet down the line... */
829 skb->protocol = htons(ETH_P_IP);
830 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
831 dev->broadcast, dev->dev_addr, skb->len) < 0) {
837 if (dev_queue_xmit(skb) < 0)
843 * Copy BOOTP-supplied string if not already set.
845 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
851 memcpy(dest, src, len);
858 * Process BOOTP extensions.
860 static void __init ic_do_bootp_ext(u8 *ext)
866 #ifdef IPCONFIG_DEBUG
869 printk("DHCP/BOOTP: Got extension %d:",*ext);
870 for (c=ext+2; c<ext+2+ext[1]; c++)
876 case 1: /* Subnet mask */
877 if (ic_netmask == NONE)
878 memcpy(&ic_netmask, ext+1, 4);
880 case 3: /* Default gateway */
881 if (ic_gateway == NONE)
882 memcpy(&ic_gateway, ext+1, 4);
884 case 6: /* DNS server */
886 if (servers > CONF_NAMESERVERS_MAX)
887 servers = CONF_NAMESERVERS_MAX;
888 for (i = 0; i < servers; i++) {
889 if (ic_nameservers[i] == NONE)
890 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
893 case 12: /* Host name */
894 ic_bootp_string(utsname()->nodename, ext+1, *ext,
896 ic_host_name_set = 1;
898 case 15: /* Domain name (DNS) */
899 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
901 case 17: /* Root path */
902 if (!root_server_path[0])
903 ic_bootp_string(root_server_path, ext+1, *ext,
904 sizeof(root_server_path));
906 case 26: /* Interface MTU */
907 memcpy(&mtu, ext+1, sizeof(mtu));
908 ic_dev_mtu = ntohs(mtu);
910 case 40: /* NIS Domain name (_not_ DNS) */
911 ic_bootp_string(utsname()->domainname, ext+1, *ext,
919 * Receive BOOTP reply.
921 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
928 if (!net_eq(dev_net(dev), &init_net))
931 /* Perform verifications before taking the lock. */
932 if (skb->pkt_type == PACKET_OTHERHOST)
935 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
938 if (!pskb_may_pull(skb,
939 sizeof(struct iphdr) +
940 sizeof(struct udphdr)))
943 b = (struct bootp_pkt *)skb_network_header(skb);
946 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
949 /* Fragments are not supported */
950 if (ip_is_fragment(h)) {
952 printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
957 if (skb->len < ntohs(h->tot_len))
960 if (ip_fast_csum((char *) h, h->ihl))
963 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
966 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
969 len = ntohs(b->udph.len) - sizeof(struct udphdr);
970 ext_len = len - (sizeof(*b) -
971 sizeof(struct iphdr) -
972 sizeof(struct udphdr) -
977 /* Ok the front looks good, make sure we can get at the rest. */
978 if (!pskb_may_pull(skb, skb->len))
981 b = (struct bootp_pkt *)skb_network_header(skb);
984 /* One reply at a time, please. */
985 spin_lock(&ic_recv_lock);
987 /* If we already have a reply, just drop the packet */
991 /* Find the ic_device that the packet arrived on */
993 while (d && d->dev != dev)
996 goto drop_unlock; /* should never happen */
998 /* Is it a reply to our BOOTP request? */
999 if (b->op != BOOTP_REPLY ||
1001 if (net_ratelimit())
1002 printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
1008 /* Is it a reply for the device we are configuring? */
1009 if (b->xid != ic_dev_xid) {
1010 if (net_ratelimit())
1011 printk(KERN_ERR "DHCP/BOOTP: Ignoring delayed packet\n");
1015 /* Parse extensions */
1017 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1018 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1021 #ifdef IPCONFIG_DHCP
1022 if (ic_proto_enabled & IC_USE_DHCP) {
1023 __be32 server_id = NONE;
1027 while (ext < end && *ext != 0xff) {
1029 if (*opt == 0) /* Padding */
1035 case 53: /* Message type */
1039 case 54: /* Server ID (IP address) */
1041 memcpy(&server_id, opt + 2, 4);
1046 #ifdef IPCONFIG_DEBUG
1047 printk("DHCP: Got message type %d\n", mt);
1052 /* While in the process of accepting one offer,
1053 * ignore all others.
1055 if (ic_myaddr != NONE)
1058 /* Let's accept that offer. */
1059 ic_myaddr = b->your_ip;
1060 ic_servaddr = server_id;
1061 #ifdef IPCONFIG_DEBUG
1062 printk("DHCP: Offered address %pI4 by server %pI4\n",
1063 &ic_myaddr, &ic_servaddr);
1065 /* The DHCP indicated server address takes
1066 * precedence over the bootp header one if
1067 * they are different.
1069 if ((server_id != NONE) &&
1070 (b->server_ip != server_id))
1071 b->server_ip = ic_servaddr;
1075 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1082 /* Urque. Forget it*/
1088 ic_dhcp_msgtype = mt;
1091 #endif /* IPCONFIG_DHCP */
1094 while (ext < end && *ext != 0xff) {
1096 if (*opt == 0) /* Padding */
1100 ic_do_bootp_ext(opt);
1104 /* We have a winner! */
1106 ic_myaddr = b->your_ip;
1107 ic_servaddr = b->server_ip;
1108 if (ic_gateway == NONE && b->relay_ip)
1109 ic_gateway = b->relay_ip;
1110 if (ic_nameservers[0] == NONE)
1111 ic_nameservers[0] = ic_servaddr;
1112 ic_got_reply = IC_BOOTP;
1115 /* Show's over. Nothing to see here. */
1116 spin_unlock(&ic_recv_lock);
1119 /* Throw the packet out. */
1130 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1133 #ifdef IPCONFIG_DYNAMIC
1135 static int __init ic_dynamic(void)
1138 struct ic_device *d;
1139 unsigned long start_jiffies, timeout, jiff;
1140 int do_bootp = ic_proto_have_if & IC_BOOTP;
1141 int do_rarp = ic_proto_have_if & IC_RARP;
1144 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1145 * This routine gets only called when some pieces of information
1146 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1148 if (!ic_proto_enabled) {
1149 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1153 #ifdef IPCONFIG_BOOTP
1154 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1155 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1157 #ifdef IPCONFIG_RARP
1158 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1159 printk(KERN_ERR "RARP: No suitable device found.\n");
1162 if (!ic_proto_have_if)
1163 /* Error message already printed */
1169 #ifdef IPCONFIG_BOOTP
1173 #ifdef IPCONFIG_RARP
1179 * Send requests and wait, until we get an answer. This loop
1180 * seems to be a terrible waste of CPU time, but actually there is
1181 * only one process running at all, so we don't need to use any
1182 * scheduler functions.
1183 * [Actually we could now, but the nothing else running note still
1186 printk(KERN_NOTICE "Sending %s%s%s requests .",
1188 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1189 (do_bootp && do_rarp) ? " and " : "",
1190 do_rarp ? "RARP" : "");
1192 start_jiffies = jiffies;
1194 retries = CONF_SEND_RETRIES;
1195 get_random_bytes(&timeout, sizeof(timeout));
1196 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1198 /* Track the device we are configuring */
1199 ic_dev_xid = d->xid;
1201 #ifdef IPCONFIG_BOOTP
1202 if (do_bootp && (d->able & IC_BOOTP))
1203 ic_bootp_send_if(d, jiffies - start_jiffies);
1205 #ifdef IPCONFIG_RARP
1206 if (do_rarp && (d->able & IC_RARP))
1210 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1211 while (time_before(jiffies, jiff) && !ic_got_reply)
1212 schedule_timeout_uninterruptible(1);
1213 #ifdef IPCONFIG_DHCP
1214 /* DHCP isn't done until we get a DHCPACK. */
1215 if ((ic_got_reply & IC_BOOTP) &&
1216 (ic_proto_enabled & IC_USE_DHCP) &&
1217 ic_dhcp_msgtype != DHCPACK) {
1219 printk(KERN_CONT ",");
1222 #endif /* IPCONFIG_DHCP */
1225 printk(KERN_CONT " OK\n");
1233 printk(KERN_CONT " timed out!\n");
1239 timeout = timeout CONF_TIMEOUT_MULT;
1240 if (timeout > CONF_TIMEOUT_MAX)
1241 timeout = CONF_TIMEOUT_MAX;
1243 printk(KERN_CONT ".");
1246 #ifdef IPCONFIG_BOOTP
1250 #ifdef IPCONFIG_RARP
1255 if (!ic_got_reply) {
1260 printk("IP-Config: Got %s answer from %pI4, ",
1261 ((ic_got_reply & IC_RARP) ? "RARP"
1262 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1264 printk(KERN_CONT "my address is %pI4\n", &ic_myaddr);
1269 #endif /* IPCONFIG_DYNAMIC */
1271 #ifdef CONFIG_PROC_FS
1273 static int pnp_seq_show(struct seq_file *seq, void *v)
1277 if (ic_proto_used & IC_PROTO)
1278 seq_printf(seq, "#PROTO: %s\n",
1279 (ic_proto_used & IC_RARP) ? "RARP"
1280 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1282 seq_puts(seq, "#MANUAL\n");
1286 "domain %s\n", ic_domain);
1287 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1288 if (ic_nameservers[i] != NONE)
1289 seq_printf(seq, "nameserver %pI4\n",
1290 &ic_nameservers[i]);
1292 if (ic_servaddr != NONE)
1293 seq_printf(seq, "bootserver %pI4\n",
1298 static int pnp_seq_open(struct inode *indoe, struct file *file)
1300 return single_open(file, pnp_seq_show, NULL);
1303 static const struct file_operations pnp_seq_fops = {
1304 .owner = THIS_MODULE,
1305 .open = pnp_seq_open,
1307 .llseek = seq_lseek,
1308 .release = single_release,
1310 #endif /* CONFIG_PROC_FS */
1313 * Extract IP address from the parameter string if needed. Note that we
1314 * need to have root_server_addr set _before_ IPConfig gets called as it
1317 __be32 __init root_nfs_parse_addr(char *name)
1324 while (octets < 4) {
1325 while (*cp >= '0' && *cp <= '9')
1327 if (cp == cq || cp - cq > 3)
1329 if (*cp == '.' || octets == 3)
1335 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1338 addr = in_aton(name);
1339 memmove(name, cp, strlen(cp) + 1);
1346 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1348 static int __init wait_for_devices(void)
1352 for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1353 struct net_device *dev;
1357 for_each_netdev(&init_net, dev) {
1358 if (ic_is_init_dev(dev)) {
1372 * IP Autoconfig dispatcher.
1375 static int __init ip_auto_config(void)
1378 #ifdef IPCONFIG_DYNAMIC
1379 int retries = CONF_OPEN_RETRIES;
1383 #ifdef CONFIG_PROC_FS
1384 proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1385 #endif /* CONFIG_PROC_FS */
1390 DBG(("IP-Config: Entered.\n"));
1391 #ifdef IPCONFIG_DYNAMIC
1394 /* Wait for devices to appear */
1395 err = wait_for_devices();
1399 /* Setup all network devices */
1400 err = ic_open_devs();
1404 /* Give drivers a chance to settle */
1405 msleep(CONF_POST_OPEN);
1408 * If the config information is insufficient (e.g., our IP address or
1409 * IP address of the boot server is missing or we have multiple network
1410 * interfaces and no default was set), use BOOTP or RARP to get the
1413 if (ic_myaddr == NONE ||
1414 #ifdef CONFIG_ROOT_NFS
1415 (root_server_addr == NONE &&
1416 ic_servaddr == NONE &&
1417 ROOT_DEV == Root_NFS) ||
1419 ic_first_dev->next) {
1420 #ifdef IPCONFIG_DYNAMIC
1421 if (ic_dynamic() < 0) {
1425 * I don't know why, but sometimes the
1426 * eepro100 driver (at least) gets upset and
1427 * doesn't work the first time it's opened.
1428 * But then if you close it and reopen it, it
1429 * works just fine. So we need to try that at
1430 * least once before giving up.
1432 * Also, if the root will be NFS-mounted, we
1433 * have nowhere to go if DHCP fails. So we
1434 * just have to keep trying forever.
1438 #ifdef CONFIG_ROOT_NFS
1439 if (ROOT_DEV == Root_NFS) {
1441 "IP-Config: Retrying forever (NFS root)...\n");
1448 "IP-Config: Reopening network devices...\n");
1452 /* Oh, well. At least we tried. */
1453 printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1456 #else /* !DYNAMIC */
1457 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1460 #endif /* IPCONFIG_DYNAMIC */
1462 /* Device selected manually or only one device -> use it */
1463 ic_dev = ic_first_dev->dev;
1466 addr = root_nfs_parse_addr(root_server_path);
1467 if (root_server_addr == NONE)
1468 root_server_addr = addr;
1471 * Use defaults wherever applicable.
1473 if (ic_defaults() < 0)
1477 * Close all network devices except the device we've
1478 * autoconfigured and set up routes.
1481 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1485 * Record which protocol was actually used.
1487 #ifdef IPCONFIG_DYNAMIC
1488 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1491 #ifndef IPCONFIG_SILENT
1493 * Clue in the operator.
1495 printk("IP-Config: Complete:\n");
1496 printk(" device=%s", ic_dev->name);
1497 printk(KERN_CONT ", addr=%pI4", &ic_myaddr);
1498 printk(KERN_CONT ", mask=%pI4", &ic_netmask);
1499 printk(KERN_CONT ", gw=%pI4", &ic_gateway);
1500 printk(KERN_CONT ",\n host=%s, domain=%s, nis-domain=%s",
1501 utsname()->nodename, ic_domain, utsname()->domainname);
1502 printk(KERN_CONT ",\n bootserver=%pI4", &ic_servaddr);
1503 printk(KERN_CONT ", rootserver=%pI4", &root_server_addr);
1504 printk(KERN_CONT ", rootpath=%s", root_server_path);
1506 printk(KERN_CONT ", mtu=%d", ic_dev_mtu);
1507 printk(KERN_CONT "\n");
1508 #endif /* !SILENT */
1513 late_initcall(ip_auto_config);
1517 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1518 * command line parameter. See Documentation/filesystems/nfs/nfsroot.txt.
1520 static int __init ic_proto_name(char *name)
1522 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1525 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1528 #ifdef CONFIG_IP_PNP_DHCP
1529 else if (!strcmp(name, "dhcp")) {
1530 ic_proto_enabled &= ~IC_RARP;
1534 #ifdef CONFIG_IP_PNP_BOOTP
1535 else if (!strcmp(name, "bootp")) {
1536 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1540 #ifdef CONFIG_IP_PNP_RARP
1541 else if (!strcmp(name, "rarp")) {
1542 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1546 #ifdef IPCONFIG_DYNAMIC
1547 else if (!strcmp(name, "both")) {
1548 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1555 static int __init ip_auto_config_setup(char *addrs)
1560 ic_set_manually = 1;
1564 * If any dhcp, bootp etc options are set, leave autoconfig on
1565 * and skip the below static IP processing.
1567 if (ic_proto_name(addrs))
1570 /* If no static IP is given, turn off autoconfig and bail. */
1572 strcmp(addrs, "off") == 0 ||
1573 strcmp(addrs, "none") == 0) {
1578 /* Parse string for static IP assignment. */
1581 if ((cp = strchr(ip, ':')))
1583 if (strlen(ip) > 0) {
1584 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1587 if ((ic_myaddr = in_aton(ip)) == ANY)
1591 if ((ic_servaddr = in_aton(ip)) == ANY)
1595 if ((ic_gateway = in_aton(ip)) == ANY)
1599 if ((ic_netmask = in_aton(ip)) == ANY)
1603 if ((dp = strchr(ip, '.'))) {
1605 strlcpy(utsname()->domainname, dp,
1606 sizeof(utsname()->domainname));
1608 strlcpy(utsname()->nodename, ip,
1609 sizeof(utsname()->nodename));
1610 ic_host_name_set = 1;
1613 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1616 if (ic_proto_name(ip) == 0 &&
1617 ic_myaddr == NONE) {
1630 static int __init nfsaddrs_config_setup(char *addrs)
1632 return ip_auto_config_setup(addrs);
1635 static int __init vendor_class_identifier_setup(char *addrs)
1637 if (strlcpy(vendor_class_identifier, addrs,
1638 sizeof(vendor_class_identifier))
1639 >= sizeof(vendor_class_identifier))
1640 printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1641 vendor_class_identifier);
1645 __setup("ip=", ip_auto_config_setup);
1646 __setup("nfsaddrs=", nfsaddrs_config_setup);
1647 __setup("dhcpclass=", vendor_class_identifier_setup);