2 * Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
3 * user-supplied information to configure own IP address and routes.
5 * Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
7 * Derived from network configuration code in fs/nfs/nfsroot.c,
8 * originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
10 * BOOTP rewritten to construct and analyse packets itself instead
11 * of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
12 * -- MJ, December 1998
14 * Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
15 * initialization scheme.
16 * - Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
18 * DHCP support added. To users this looks like a whole separate
19 * protocol, but we know it's just a bag on the side of BOOTP.
20 * -- Chip Salzenberg <chip@valinux.com>, May 2000
22 * Ported DHCP support from 2.2.16 to 2.4.0-test4
23 * -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
25 * Merged changes from 2.2.19 into 2.4.3
26 * -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
28 * Multiple Nameservers in /proc/net/pnp
29 * -- Josef Siemes <jsiemes@web.de>, Aug 2002
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/kernel.h>
35 #include <linux/jiffies.h>
36 #include <linux/random.h>
37 #include <linux/init.h>
38 #include <linux/utsname.h>
41 #include <linux/inet.h>
42 #include <linux/inetdevice.h>
43 #include <linux/netdevice.h>
44 #include <linux/if_arp.h>
45 #include <linux/skbuff.h>
47 #include <linux/socket.h>
48 #include <linux/route.h>
49 #include <linux/udp.h>
50 #include <linux/proc_fs.h>
51 #include <linux/seq_file.h>
52 #include <linux/major.h>
53 #include <linux/root_dev.h>
54 #include <linux/delay.h>
55 #include <linux/nfs_fs.h>
56 #include <linux/slab.h>
57 #include <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 #if defined(CONFIG_IP_PNP_DHCP)
71 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
72 #define IPCONFIG_BOOTP
74 #if defined(CONFIG_IP_PNP_RARP)
77 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
78 #define IPCONFIG_DYNAMIC
81 /* Define the friendly delay before and after opening net devices */
82 #define CONF_POST_OPEN 10 /* After opening: 10 msecs */
83 #define CONF_CARRIER_TIMEOUT 120000 /* Wait for carrier timeout */
85 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
86 #define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */
87 #define CONF_SEND_RETRIES 6 /* Send six requests per open */
88 #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
89 #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
90 #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
91 #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
92 #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
93 - '3' from resolv.h */
95 #define NONE cpu_to_be32(INADDR_NONE)
96 #define ANY cpu_to_be32(INADDR_ANY)
99 * Public IP configuration
102 /* This is used by platforms which might be able to set the ipconfig
103 * variables using firmware environment vars. If this is set, it will
104 * ignore such firmware variables.
106 int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
108 static int ic_enable __initdata; /* IP config enabled? */
110 /* Protocol choice */
111 int ic_proto_enabled __initdata = 0
112 #ifdef IPCONFIG_BOOTP
115 #ifdef CONFIG_IP_PNP_DHCP
123 static int ic_host_name_set __initdata; /* Host name set by us? */
125 __be32 ic_myaddr = NONE; /* My IP address */
126 static __be32 ic_netmask = NONE; /* Netmask for local subnet */
127 __be32 ic_gateway = NONE; /* Gateway IP address */
129 #ifdef IPCONFIG_DYNAMIC
130 static __be32 ic_addrservaddr = NONE; /* IP Address of the IP addresses'server */
133 __be32 ic_servaddr = NONE; /* Boot server IP address */
135 __be32 root_server_addr = NONE; /* Address of NFS server */
136 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
138 /* vendor class identifier */
139 static char vendor_class_identifier[253] __initdata;
141 #if defined(CONFIG_IP_PNP_DHCP)
142 static char dhcp_client_identifier[253] __initdata;
145 /* Persistent data: */
147 #ifdef IPCONFIG_DYNAMIC
148 static int ic_proto_used; /* Protocol used, if any */
150 #define ic_proto_used 0
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;
165 /* MTU for boot device */
166 static int ic_dev_mtu __initdata;
168 #ifdef IPCONFIG_DYNAMIC
169 static DEFINE_SPINLOCK(ic_recv_lock);
170 static volatile int ic_got_reply __initdata; /* Proto(s) that replied */
173 static int ic_dhcp_msgtype __initdata; /* 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; /* List of open device */
190 static struct ic_device *ic_dev __initdata; /* 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;
207 unsigned long start, next_msg;
209 last = &ic_first_dev;
212 /* bring loopback and DSA master network devices up first */
213 for_each_netdev(&init_net, dev) {
214 if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
216 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
217 pr_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 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
227 dev->name, dev->mtu);
228 if (!(dev->flags & IFF_NOARP))
230 able &= ic_proto_enabled;
231 if (ic_proto_enabled && !able)
234 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
235 pr_err("IP-Config: Failed to open %s\n",
239 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
249 get_random_bytes(&d->xid, sizeof(__be32));
252 ic_proto_have_if |= able;
253 pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
254 dev->name, able, d->xid);
258 /* no point in waiting if we could not bring up at least one device */
262 /* wait for a carrier on at least one device */
264 next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
265 while (time_before(jiffies, start +
266 msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
269 for_each_netdev(&init_net, dev)
270 if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
275 if (time_before(jiffies, next_msg))
278 elapsed = jiffies_to_msecs(jiffies - start);
279 wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
280 pr_info("Waiting up to %d more seconds for network.\n", wait);
281 next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
289 if (user_dev_name[0])
290 pr_err("IP-Config: Device `%s' not found\n",
293 pr_err("IP-Config: No network devices available\n");
299 static void __init ic_close_devs(void)
301 struct ic_device *d, *next;
302 struct net_device *dev;
309 if (d != ic_dev && !netdev_uses_dsa(dev)) {
310 pr_debug("IP-Config: Downing %s\n", dev->name);
311 dev_change_flags(dev, d->flags);
319 * Interface to various network functions.
323 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
325 sin->sin_family = AF_INET;
326 sin->sin_addr.s_addr = addr;
327 sin->sin_port = port;
330 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
334 mm_segment_t oldfs = get_fs();
336 res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
341 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
345 mm_segment_t oldfs = get_fs();
347 res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
352 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
356 mm_segment_t oldfs = get_fs();
358 res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
364 * Set up interface addresses and routes.
367 static int __init ic_setup_if(void)
370 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
373 memset(&ir, 0, sizeof(ir));
374 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
375 set_sockaddr(sin, ic_myaddr, 0);
376 if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
377 pr_err("IP-Config: Unable to set interface address (%d)\n",
381 set_sockaddr(sin, ic_netmask, 0);
382 if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
383 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
387 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
388 if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
389 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
393 /* Handle the case where we need non-standard MTU on the boot link (a network
394 * using jumbo frames, for instance). If we can't set the mtu, don't error
395 * out, we'll try to muddle along.
397 if (ic_dev_mtu != 0) {
398 strcpy(ir.ifr_name, ic_dev->dev->name);
399 ir.ifr_mtu = ic_dev_mtu;
400 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
401 pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
407 static int __init ic_setup_routes(void)
409 /* No need to setup device routes, only the default route... */
411 if (ic_gateway != NONE) {
415 memset(&rm, 0, sizeof(rm));
416 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
417 pr_err("IP-Config: Gateway not on directly connected network\n");
420 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
421 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
422 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
423 rm.rt_flags = RTF_UP | RTF_GATEWAY;
424 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
425 pr_err("IP-Config: Cannot add default route (%d)\n",
435 * Fill in default values for all missing parameters.
438 static int __init ic_defaults(void)
441 * At this point we have no userspace running so need not
442 * claim locks on system_utsname
445 if (!ic_host_name_set)
446 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
448 if (root_server_addr == NONE)
449 root_server_addr = ic_servaddr;
451 if (ic_netmask == NONE) {
452 if (IN_CLASSA(ntohl(ic_myaddr)))
453 ic_netmask = htonl(IN_CLASSA_NET);
454 else if (IN_CLASSB(ntohl(ic_myaddr)))
455 ic_netmask = htonl(IN_CLASSB_NET);
456 else if (IN_CLASSC(ntohl(ic_myaddr)))
457 ic_netmask = htonl(IN_CLASSC_NET);
459 pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
463 pr_notice("IP-Config: Guessing netmask %pI4\n",
476 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
478 static struct packet_type rarp_packet_type __initdata = {
479 .type = cpu_to_be16(ETH_P_RARP),
480 .func = ic_rarp_recv,
483 static inline void __init ic_rarp_init(void)
485 dev_add_pack(&rarp_packet_type);
488 static inline void __init ic_rarp_cleanup(void)
490 dev_remove_pack(&rarp_packet_type);
494 * Process received RARP packet.
497 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
500 unsigned char *rarp_ptr;
502 unsigned char *tha; /* t for "target" */
505 if (!net_eq(dev_net(dev), &init_net))
508 skb = skb_share_check(skb, GFP_ATOMIC);
512 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
515 /* Basic sanity checks can be done without the lock. */
516 rarp = (struct arphdr *)skb_transport_header(skb);
518 /* If this test doesn't pass, it's not IP, or we should
521 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
524 /* If it's not a RARP reply, delete it. */
525 if (rarp->ar_op != htons(ARPOP_RREPLY))
528 /* If it's not Ethernet, delete it. */
529 if (rarp->ar_pro != htons(ETH_P_IP))
532 if (!pskb_may_pull(skb, arp_hdr_len(dev)))
535 /* OK, it is all there and looks valid, process... */
536 rarp = (struct arphdr *)skb_transport_header(skb);
537 rarp_ptr = (unsigned char *) (rarp + 1);
539 /* One reply at a time, please. */
540 spin_lock(&ic_recv_lock);
542 /* If we already have a reply, just drop the packet */
546 /* Find the ic_device that the packet arrived on */
548 while (d && d->dev != dev)
551 goto drop_unlock; /* should never happen */
553 /* Extract variable-width fields */
554 rarp_ptr += dev->addr_len;
555 memcpy(&sip, rarp_ptr, 4);
558 rarp_ptr += dev->addr_len;
559 memcpy(&tip, rarp_ptr, 4);
561 /* Discard packets which are not meant for us. */
562 if (memcmp(tha, dev->dev_addr, dev->addr_len))
565 /* Discard packets which are not from specified server. */
566 if (ic_servaddr != NONE && ic_servaddr != sip)
569 /* We have a winner! */
571 if (ic_myaddr == NONE)
574 ic_addrservaddr = sip;
575 ic_got_reply = IC_RARP;
578 /* Show's over. Nothing to see here. */
579 spin_unlock(&ic_recv_lock);
582 /* Throw the packet out. */
589 * Send RARP request packet over a single interface.
591 static void __init ic_rarp_send_if(struct ic_device *d)
593 struct net_device *dev = d->dev;
594 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
595 dev->dev_addr, dev->dev_addr);
600 * Predefine Nameservers
602 static inline void __init ic_nameservers_predef(void)
606 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
607 ic_nameservers[i] = NONE;
611 * DHCP/BOOTP support.
614 #ifdef IPCONFIG_BOOTP
616 struct bootp_pkt { /* BOOTP packet format */
617 struct iphdr iph; /* IP header */
618 struct udphdr udph; /* UDP header */
619 u8 op; /* 1=request, 2=reply */
620 u8 htype; /* HW address type */
621 u8 hlen; /* HW address length */
622 u8 hops; /* Used only by gateways */
623 __be32 xid; /* Transaction ID */
624 __be16 secs; /* Seconds since we started */
625 __be16 flags; /* Just what it says */
626 __be32 client_ip; /* Client's IP address if known */
627 __be32 your_ip; /* Assigned IP address */
628 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
629 __be32 relay_ip; /* IP address of BOOTP relay */
630 u8 hw_addr[16]; /* Client's HW address */
631 u8 serv_name[64]; /* Server host name */
632 u8 boot_file[128]; /* Name of boot file */
633 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
637 #define BOOTP_REQUEST 1
638 #define BOOTP_REPLY 2
640 /* DHCP message types */
641 #define DHCPDISCOVER 1
643 #define DHCPREQUEST 3
644 #define DHCPDECLINE 4
647 #define DHCPRELEASE 7
650 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
652 static struct packet_type bootp_packet_type __initdata = {
653 .type = cpu_to_be16(ETH_P_IP),
654 .func = ic_bootp_recv,
658 * Initialize DHCP/BOOTP extension fields in the request.
661 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
666 ic_dhcp_init_options(u8 *options, struct ic_device *d)
668 u8 mt = ((ic_servaddr == NONE)
669 ? DHCPDISCOVER : DHCPREQUEST);
673 pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
675 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
678 *e++ = 53; /* DHCP message type */
682 if (mt == DHCPREQUEST) {
683 *e++ = 54; /* Server ID (IP address) */
685 memcpy(e, &ic_servaddr, 4);
688 *e++ = 50; /* Requested IP address */
690 memcpy(e, &ic_myaddr, 4);
696 static const u8 ic_req_params[] = {
698 3, /* Default gateway */
701 15, /* Domain name */
704 40, /* NIS domain name */
707 *e++ = 55; /* Parameter request list */
708 *e++ = sizeof(ic_req_params);
709 memcpy(e, ic_req_params, sizeof(ic_req_params));
710 e += sizeof(ic_req_params);
712 if (ic_host_name_set) {
713 *e++ = 12; /* host-name */
714 len = strlen(utsname()->nodename);
716 memcpy(e, utsname()->nodename, len);
719 if (*vendor_class_identifier) {
720 pr_info("DHCP: sending class identifier \"%s\"\n",
721 vendor_class_identifier);
722 *e++ = 60; /* Class-identifier */
723 len = strlen(vendor_class_identifier);
725 memcpy(e, vendor_class_identifier, len);
728 len = strlen(dhcp_client_identifier + 1);
729 /* the minimum length of identifier is 2, include 1 byte type,
730 * and can not be larger than the length of options
732 if (len >= 1 && len < 312 - (e - options) - 1) {
735 memcpy(e, dhcp_client_identifier, len + 1);
740 *e++ = 255; /* End of the list */
743 #endif /* IPCONFIG_DHCP */
745 static void __init ic_bootp_init_ext(u8 *e)
747 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
749 *e++ = 1; /* Subnet mask request */
752 *e++ = 3; /* Default gateway request */
755 *e++ = 5; /* Name server request */
758 *e++ = 12; /* Host name request */
761 *e++ = 40; /* NIS Domain name request */
764 *e++ = 17; /* Boot path */
768 *e++ = 57; /* set extension buffer size for reply */
770 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
773 *e++ = 255; /* End of the list */
778 * Initialize the DHCP/BOOTP mechanism.
780 static inline void __init ic_bootp_init(void)
782 /* Re-initialise all name servers to NONE, in case any were set via the
783 * "ip=" or "nfsaddrs=" kernel command line parameters: any IP addresses
784 * specified there will already have been decoded but are no longer
787 ic_nameservers_predef();
789 dev_add_pack(&bootp_packet_type);
794 * DHCP/BOOTP cleanup.
796 static inline void __init ic_bootp_cleanup(void)
798 dev_remove_pack(&bootp_packet_type);
803 * Send DHCP/BOOTP request to single interface.
805 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
807 struct net_device *dev = d->dev;
811 int hlen = LL_RESERVED_SPACE(dev);
812 int tlen = dev->needed_tailroom;
814 /* Allocate packet */
815 skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
819 skb_reserve(skb, hlen);
820 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
821 memset(b, 0, sizeof(struct bootp_pkt));
823 /* Construct IP header */
824 skb_reset_network_header(skb);
828 h->tot_len = htons(sizeof(struct bootp_pkt));
829 h->frag_off = htons(IP_DF);
831 h->protocol = IPPROTO_UDP;
832 h->daddr = htonl(INADDR_BROADCAST);
833 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
835 /* Construct UDP header */
836 b->udph.source = htons(68);
837 b->udph.dest = htons(67);
838 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
839 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
841 /* Construct DHCP/BOOTP header */
842 b->op = BOOTP_REQUEST;
843 if (dev->type < 256) /* check for false types */
844 b->htype = dev->type;
845 else if (dev->type == ARPHRD_FDDI)
846 b->htype = ARPHRD_ETHER;
848 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
850 b->htype = dev->type; /* can cause undefined behavior */
853 /* server_ip and your_ip address are both already zero per RFC2131 */
854 b->hlen = dev->addr_len;
855 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
856 b->secs = htons(jiffies_diff / HZ);
859 /* add DHCP options or BOOTP extensions */
861 if (ic_proto_enabled & IC_USE_DHCP)
862 ic_dhcp_init_options(b->exten, d);
865 ic_bootp_init_ext(b->exten);
867 /* Chain packet down the line... */
869 skb->protocol = htons(ETH_P_IP);
870 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
871 dev->broadcast, dev->dev_addr, skb->len) < 0) {
877 if (dev_queue_xmit(skb) < 0)
883 * Copy BOOTP-supplied string
885 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
891 memcpy(dest, src, len);
898 * Process BOOTP extensions.
900 static void __init ic_do_bootp_ext(u8 *ext)
908 pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
909 for (c=ext+2; c<ext+2+ext[1]; c++)
910 pr_debug(" %02x", *c);
914 case 1: /* Subnet mask */
915 if (ic_netmask == NONE)
916 memcpy(&ic_netmask, ext+1, 4);
918 case 3: /* Default gateway */
919 if (ic_gateway == NONE)
920 memcpy(&ic_gateway, ext+1, 4);
922 case 6: /* DNS server */
924 if (servers > CONF_NAMESERVERS_MAX)
925 servers = CONF_NAMESERVERS_MAX;
926 for (i = 0; i < servers; i++) {
927 if (ic_nameservers[i] == NONE)
928 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
931 case 12: /* Host name */
932 if (!ic_host_name_set) {
933 ic_bootp_string(utsname()->nodename, ext+1, *ext,
935 ic_host_name_set = 1;
938 case 15: /* Domain name (DNS) */
940 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
942 case 17: /* Root path */
943 if (!root_server_path[0])
944 ic_bootp_string(root_server_path, ext+1, *ext,
945 sizeof(root_server_path));
947 case 26: /* Interface MTU */
948 memcpy(&mtu, ext+1, sizeof(mtu));
949 ic_dev_mtu = ntohs(mtu);
951 case 40: /* NIS Domain name (_not_ DNS) */
952 ic_bootp_string(utsname()->domainname, ext+1, *ext,
960 * Receive BOOTP reply.
962 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
969 if (!net_eq(dev_net(dev), &init_net))
972 /* Perform verifications before taking the lock. */
973 if (skb->pkt_type == PACKET_OTHERHOST)
976 skb = skb_share_check(skb, GFP_ATOMIC);
980 if (!pskb_may_pull(skb,
981 sizeof(struct iphdr) +
982 sizeof(struct udphdr)))
985 b = (struct bootp_pkt *)skb_network_header(skb);
988 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
991 /* Fragments are not supported */
992 if (ip_is_fragment(h)) {
993 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
997 if (skb->len < ntohs(h->tot_len))
1000 if (ip_fast_csum((char *) h, h->ihl))
1003 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
1006 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1009 len = ntohs(b->udph.len) - sizeof(struct udphdr);
1010 ext_len = len - (sizeof(*b) -
1011 sizeof(struct iphdr) -
1012 sizeof(struct udphdr) -
1017 /* Ok the front looks good, make sure we can get at the rest. */
1018 if (!pskb_may_pull(skb, skb->len))
1021 b = (struct bootp_pkt *)skb_network_header(skb);
1024 /* One reply at a time, please. */
1025 spin_lock(&ic_recv_lock);
1027 /* If we already have a reply, just drop the packet */
1031 /* Find the ic_device that the packet arrived on */
1033 while (d && d->dev != dev)
1036 goto drop_unlock; /* should never happen */
1038 /* Is it a reply to our BOOTP request? */
1039 if (b->op != BOOTP_REPLY ||
1041 net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1042 d->dev->name, b->op, b->xid);
1046 /* Parse extensions */
1048 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1049 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1052 #ifdef IPCONFIG_DHCP
1053 if (ic_proto_enabled & IC_USE_DHCP) {
1054 __be32 server_id = NONE;
1058 while (ext < end && *ext != 0xff) {
1060 if (*opt == 0) /* Padding */
1066 case 53: /* Message type */
1070 case 54: /* Server ID (IP address) */
1072 memcpy(&server_id, opt + 2, 4);
1077 pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name);
1081 /* While in the process of accepting one offer,
1082 * ignore all others.
1084 if (ic_myaddr != NONE)
1087 /* Let's accept that offer. */
1088 ic_myaddr = b->your_ip;
1089 ic_servaddr = server_id;
1090 pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1091 &ic_myaddr, &b->iph.saddr);
1092 /* The DHCP indicated server address takes
1093 * precedence over the bootp header one if
1094 * they are different.
1096 if ((server_id != NONE) &&
1097 (b->server_ip != server_id))
1098 b->server_ip = ic_servaddr;
1102 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1109 /* Urque. Forget it*/
1115 ic_dhcp_msgtype = mt;
1118 #endif /* IPCONFIG_DHCP */
1121 while (ext < end && *ext != 0xff) {
1123 if (*opt == 0) /* Padding */
1127 ic_do_bootp_ext(opt);
1131 /* We have a winner! */
1133 ic_myaddr = b->your_ip;
1134 ic_servaddr = b->server_ip;
1135 ic_addrservaddr = b->iph.saddr;
1136 if (ic_gateway == NONE && b->relay_ip)
1137 ic_gateway = b->relay_ip;
1138 if (ic_nameservers[0] == NONE)
1139 ic_nameservers[0] = ic_servaddr;
1140 ic_got_reply = IC_BOOTP;
1143 /* Show's over. Nothing to see here. */
1144 spin_unlock(&ic_recv_lock);
1147 /* Throw the packet out. */
1158 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1161 #ifdef IPCONFIG_DYNAMIC
1163 static int __init ic_dynamic(void)
1166 struct ic_device *d;
1167 unsigned long start_jiffies, timeout, jiff;
1168 int do_bootp = ic_proto_have_if & IC_BOOTP;
1169 int do_rarp = ic_proto_have_if & IC_RARP;
1172 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1173 * This routine gets only called when some pieces of information
1174 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1176 if (!ic_proto_enabled) {
1177 pr_err("IP-Config: Incomplete network configuration information\n");
1181 #ifdef IPCONFIG_BOOTP
1182 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1183 pr_err("DHCP/BOOTP: No suitable device found\n");
1185 #ifdef IPCONFIG_RARP
1186 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1187 pr_err("RARP: No suitable device found\n");
1190 if (!ic_proto_have_if)
1191 /* Error message already printed */
1197 #ifdef IPCONFIG_BOOTP
1201 #ifdef IPCONFIG_RARP
1207 * Send requests and wait, until we get an answer. This loop
1208 * seems to be a terrible waste of CPU time, but actually there is
1209 * only one process running at all, so we don't need to use any
1210 * scheduler functions.
1211 * [Actually we could now, but the nothing else running note still
1214 pr_notice("Sending %s%s%s requests .",
1216 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1217 (do_bootp && do_rarp) ? " and " : "",
1218 do_rarp ? "RARP" : "");
1220 start_jiffies = jiffies;
1222 retries = CONF_SEND_RETRIES;
1223 get_random_bytes(&timeout, sizeof(timeout));
1224 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1226 #ifdef IPCONFIG_BOOTP
1227 if (do_bootp && (d->able & IC_BOOTP))
1228 ic_bootp_send_if(d, jiffies - start_jiffies);
1230 #ifdef IPCONFIG_RARP
1231 if (do_rarp && (d->able & IC_RARP))
1236 jiff = jiffies + timeout;
1237 while (time_before(jiffies, jiff) && !ic_got_reply)
1238 schedule_timeout_uninterruptible(1);
1240 #ifdef IPCONFIG_DHCP
1241 /* DHCP isn't done until we get a DHCPACK. */
1242 if ((ic_got_reply & IC_BOOTP) &&
1243 (ic_proto_enabled & IC_USE_DHCP) &&
1244 ic_dhcp_msgtype != DHCPACK) {
1246 /* continue on device that got the reply */
1251 #endif /* IPCONFIG_DHCP */
1262 pr_cont(" timed out!\n");
1268 timeout = timeout CONF_TIMEOUT_MULT;
1269 if (timeout > CONF_TIMEOUT_MAX)
1270 timeout = CONF_TIMEOUT_MAX;
1275 #ifdef IPCONFIG_BOOTP
1279 #ifdef IPCONFIG_RARP
1284 if (!ic_got_reply) {
1289 pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1290 ((ic_got_reply & IC_RARP) ? "RARP"
1291 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1292 &ic_addrservaddr, &ic_myaddr);
1297 #endif /* IPCONFIG_DYNAMIC */
1299 #ifdef CONFIG_PROC_FS
1301 static int pnp_seq_show(struct seq_file *seq, void *v)
1305 if (ic_proto_used & IC_PROTO)
1306 seq_printf(seq, "#PROTO: %s\n",
1307 (ic_proto_used & IC_RARP) ? "RARP"
1308 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1310 seq_puts(seq, "#MANUAL\n");
1314 "domain %s\n", ic_domain);
1315 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1316 if (ic_nameservers[i] != NONE)
1317 seq_printf(seq, "nameserver %pI4\n",
1318 &ic_nameservers[i]);
1320 if (ic_servaddr != NONE)
1321 seq_printf(seq, "bootserver %pI4\n",
1326 static int pnp_seq_open(struct inode *indoe, struct file *file)
1328 return single_open(file, pnp_seq_show, NULL);
1331 static const struct file_operations pnp_seq_fops = {
1332 .owner = THIS_MODULE,
1333 .open = pnp_seq_open,
1335 .llseek = seq_lseek,
1336 .release = single_release,
1338 #endif /* CONFIG_PROC_FS */
1341 * Extract IP address from the parameter string if needed. Note that we
1342 * need to have root_server_addr set _before_ IPConfig gets called as it
1345 __be32 __init root_nfs_parse_addr(char *name)
1352 while (octets < 4) {
1353 while (*cp >= '0' && *cp <= '9')
1355 if (cp == cq || cp - cq > 3)
1357 if (*cp == '.' || octets == 3)
1363 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1366 addr = in_aton(name);
1367 memmove(name, cp, strlen(cp) + 1);
1374 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1376 static int __init wait_for_devices(void)
1380 for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1381 struct net_device *dev;
1385 for_each_netdev(&init_net, dev) {
1386 if (ic_is_init_dev(dev)) {
1400 * IP Autoconfig dispatcher.
1403 static int __init ip_auto_config(void)
1406 #ifdef IPCONFIG_DYNAMIC
1407 int retries = CONF_OPEN_RETRIES;
1412 /* Initialise all name servers to NONE (but only if the "ip=" or
1413 * "nfsaddrs=" kernel command line parameters weren't decoded, otherwise
1414 * we'll overwrite the IP addresses specified there)
1416 if (ic_set_manually == 0)
1417 ic_nameservers_predef();
1419 #ifdef CONFIG_PROC_FS
1420 proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1421 #endif /* CONFIG_PROC_FS */
1426 pr_debug("IP-Config: Entered.\n");
1427 #ifdef IPCONFIG_DYNAMIC
1430 /* Wait for devices to appear */
1431 err = wait_for_devices();
1435 /* Setup all network devices */
1436 err = ic_open_devs();
1440 /* Give drivers a chance to settle */
1441 msleep(CONF_POST_OPEN);
1444 * If the config information is insufficient (e.g., our IP address or
1445 * IP address of the boot server is missing or we have multiple network
1446 * interfaces and no default was set), use BOOTP or RARP to get the
1449 if (ic_myaddr == NONE ||
1450 #ifdef CONFIG_ROOT_NFS
1451 (root_server_addr == NONE &&
1452 ic_servaddr == NONE &&
1453 ROOT_DEV == Root_NFS) ||
1455 ic_first_dev->next) {
1456 #ifdef IPCONFIG_DYNAMIC
1457 if (ic_dynamic() < 0) {
1461 * I don't know why, but sometimes the
1462 * eepro100 driver (at least) gets upset and
1463 * doesn't work the first time it's opened.
1464 * But then if you close it and reopen it, it
1465 * works just fine. So we need to try that at
1466 * least once before giving up.
1468 * Also, if the root will be NFS-mounted, we
1469 * have nowhere to go if DHCP fails. So we
1470 * just have to keep trying forever.
1474 #ifdef CONFIG_ROOT_NFS
1475 if (ROOT_DEV == Root_NFS) {
1476 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1482 pr_err("IP-Config: Reopening network devices...\n");
1486 /* Oh, well. At least we tried. */
1487 pr_err("IP-Config: Auto-configuration of network failed\n");
1490 #else /* !DYNAMIC */
1491 pr_err("IP-Config: Incomplete network configuration information\n");
1494 #endif /* IPCONFIG_DYNAMIC */
1496 /* Device selected manually or only one device -> use it */
1497 ic_dev = ic_first_dev;
1500 addr = root_nfs_parse_addr(root_server_path);
1501 if (root_server_addr == NONE)
1502 root_server_addr = addr;
1505 * Use defaults wherever applicable.
1507 if (ic_defaults() < 0)
1511 * Record which protocol was actually used.
1513 #ifdef IPCONFIG_DYNAMIC
1514 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1517 #ifndef IPCONFIG_SILENT
1519 * Clue in the operator.
1521 pr_info("IP-Config: Complete:\n");
1523 pr_info(" device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1524 ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1525 &ic_myaddr, &ic_netmask, &ic_gateway);
1526 pr_info(" host=%s, domain=%s, nis-domain=%s\n",
1527 utsname()->nodename, ic_domain, utsname()->domainname);
1528 pr_info(" bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1529 &ic_servaddr, &root_server_addr, root_server_path);
1531 pr_cont(", mtu=%d", ic_dev_mtu);
1532 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1533 if (ic_nameservers[i] != NONE) {
1534 pr_cont(" nameserver%u=%pI4",
1535 i, &ic_nameservers[i]);
1538 for (i++; i < CONF_NAMESERVERS_MAX; i++)
1539 if (ic_nameservers[i] != NONE)
1540 pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1542 #endif /* !SILENT */
1545 * Close all network devices except the device we've
1546 * autoconfigured and set up routes.
1548 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1558 late_initcall(ip_auto_config);
1562 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1563 * command line parameter. See Documentation/filesystems/nfs/nfsroot.txt.
1565 static int __init ic_proto_name(char *name)
1567 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1570 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1573 #ifdef CONFIG_IP_PNP_DHCP
1574 else if (!strncmp(name, "dhcp", 4)) {
1577 ic_proto_enabled &= ~IC_RARP;
1578 client_id = strstr(name, "dhcp,");
1582 client_id = client_id + 5;
1583 v = strchr(client_id, ',');
1587 if (kstrtou8(client_id, 0, dhcp_client_identifier))
1588 pr_debug("DHCP: Invalid client identifier type\n");
1589 strncpy(dhcp_client_identifier + 1, v + 1, 251);
1595 #ifdef CONFIG_IP_PNP_BOOTP
1596 else if (!strcmp(name, "bootp")) {
1597 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1601 #ifdef CONFIG_IP_PNP_RARP
1602 else if (!strcmp(name, "rarp")) {
1603 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1607 #ifdef IPCONFIG_DYNAMIC
1608 else if (!strcmp(name, "both")) {
1609 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1616 static int __init ip_auto_config_setup(char *addrs)
1621 ic_set_manually = 1;
1625 * If any dhcp, bootp etc options are set, leave autoconfig on
1626 * and skip the below static IP processing.
1628 if (ic_proto_name(addrs))
1631 /* If no static IP is given, turn off autoconfig and bail. */
1633 strcmp(addrs, "off") == 0 ||
1634 strcmp(addrs, "none") == 0) {
1639 /* Initialise all name servers to NONE */
1640 ic_nameservers_predef();
1642 /* Parse string for static IP assignment. */
1645 if ((cp = strchr(ip, ':')))
1647 if (strlen(ip) > 0) {
1648 pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1651 if ((ic_myaddr = in_aton(ip)) == ANY)
1655 if ((ic_servaddr = in_aton(ip)) == ANY)
1659 if ((ic_gateway = in_aton(ip)) == ANY)
1663 if ((ic_netmask = in_aton(ip)) == ANY)
1667 if ((dp = strchr(ip, '.'))) {
1669 strlcpy(utsname()->domainname, dp,
1670 sizeof(utsname()->domainname));
1672 strlcpy(utsname()->nodename, ip,
1673 sizeof(utsname()->nodename));
1674 ic_host_name_set = 1;
1677 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1680 if (ic_proto_name(ip) == 0 &&
1681 ic_myaddr == NONE) {
1686 if (CONF_NAMESERVERS_MAX >= 1) {
1687 ic_nameservers[0] = in_aton(ip);
1688 if (ic_nameservers[0] == ANY)
1689 ic_nameservers[0] = NONE;
1693 if (CONF_NAMESERVERS_MAX >= 2) {
1694 ic_nameservers[1] = in_aton(ip);
1695 if (ic_nameservers[1] == ANY)
1696 ic_nameservers[1] = NONE;
1707 __setup("ip=", ip_auto_config_setup);
1709 static int __init nfsaddrs_config_setup(char *addrs)
1711 return ip_auto_config_setup(addrs);
1713 __setup("nfsaddrs=", nfsaddrs_config_setup);
1715 static int __init vendor_class_identifier_setup(char *addrs)
1717 if (strlcpy(vendor_class_identifier, addrs,
1718 sizeof(vendor_class_identifier))
1719 >= sizeof(vendor_class_identifier))
1720 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1721 vendor_class_identifier);
1724 __setup("dhcpclass=", vendor_class_identifier_setup);