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 /* 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_addrservaddr = NONE; /* IP Address of the IP addresses'server */
141 __be32 ic_servaddr = NONE; /* Boot server IP address */
143 __be32 root_server_addr = NONE; /* Address of NFS server */
144 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
146 __be32 ic_dev_xid; /* Device under configuration */
148 /* vendor class identifier */
149 static char vendor_class_identifier[253] __initdata;
151 /* Persistent data: */
153 static int ic_proto_used; /* Protocol used, if any */
154 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
155 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
161 /* Name of user-selected boot device */
162 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
164 /* Protocols supported by available interfaces */
165 static int ic_proto_have_if __initdata = 0;
167 /* MTU for boot device */
168 static int ic_dev_mtu __initdata = 0;
170 #ifdef IPCONFIG_DYNAMIC
171 static DEFINE_SPINLOCK(ic_recv_lock);
172 static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
175 static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
184 struct ic_device *next;
185 struct net_device *dev;
186 unsigned short flags;
191 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
192 static struct net_device *ic_dev __initdata = NULL; /* Selected device */
194 static bool __init ic_is_init_dev(struct net_device *dev)
196 if (dev->flags & IFF_LOOPBACK)
198 return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
199 (!(dev->flags & IFF_LOOPBACK) &&
200 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
201 strncmp(dev->name, "dummy", 5));
204 static int __init ic_open_devs(void)
206 struct ic_device *d, **last;
207 struct net_device *dev;
208 unsigned short oflags;
209 unsigned long start, next_msg;
211 last = &ic_first_dev;
214 /* bring loopback device up first */
215 for_each_netdev(&init_net, dev) {
216 if (!(dev->flags & IFF_LOOPBACK))
218 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
219 pr_err("IP-Config: Failed to open %s\n", dev->name);
222 for_each_netdev(&init_net, dev) {
223 if (ic_is_init_dev(dev)) {
228 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small",
229 dev->name, dev->mtu);
230 if (!(dev->flags & IFF_NOARP))
232 able &= ic_proto_enabled;
233 if (ic_proto_enabled && !able)
236 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
237 pr_err("IP-Config: Failed to open %s\n",
241 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
251 get_random_bytes(&d->xid, sizeof(__be32));
254 ic_proto_have_if |= able;
255 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
256 dev->name, able, d->xid));
260 /* no point in waiting if we could not bring up at least one device */
264 /* wait for a carrier on at least one device */
266 next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
267 while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
270 for_each_netdev(&init_net, dev)
271 if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
276 if time_before(jiffies, next_msg)
279 elapsed = jiffies_to_msecs(jiffies - start);
280 wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
281 pr_info("Waiting up to %d more seconds for network.\n", wait);
282 next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
290 if (user_dev_name[0])
291 pr_err("IP-Config: Device `%s' not found\n",
294 pr_err("IP-Config: No network devices available\n");
300 static void __init ic_close_devs(void)
302 struct ic_device *d, *next;
303 struct net_device *dev;
311 DBG(("IP-Config: Downing %s\n", dev->name));
312 dev_change_flags(dev, d->flags);
320 * Interface to various network functions.
324 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
326 sin->sin_family = AF_INET;
327 sin->sin_addr.s_addr = addr;
328 sin->sin_port = port;
331 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
335 mm_segment_t oldfs = get_fs();
337 res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
342 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
346 mm_segment_t oldfs = get_fs();
348 res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
353 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
357 mm_segment_t oldfs = get_fs();
359 res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
365 * Set up interface addresses and routes.
368 static int __init ic_setup_if(void)
371 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
374 memset(&ir, 0, sizeof(ir));
375 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
376 set_sockaddr(sin, ic_myaddr, 0);
377 if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
378 pr_err("IP-Config: Unable to set interface address (%d)\n",
382 set_sockaddr(sin, ic_netmask, 0);
383 if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
384 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
388 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
389 if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
390 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
394 /* Handle the case where we need non-standard MTU on the boot link (a network
395 * using jumbo frames, for instance). If we can't set the mtu, don't error
396 * out, we'll try to muddle along.
398 if (ic_dev_mtu != 0) {
399 strcpy(ir.ifr_name, ic_dev->name);
400 ir.ifr_mtu = ic_dev_mtu;
401 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
402 pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
408 static int __init ic_setup_routes(void)
410 /* No need to setup device routes, only the default route... */
412 if (ic_gateway != NONE) {
416 memset(&rm, 0, sizeof(rm));
417 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
418 pr_err("IP-Config: Gateway not on directly connected network\n");
421 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
422 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
423 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
424 rm.rt_flags = RTF_UP | RTF_GATEWAY;
425 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
426 pr_err("IP-Config: Cannot add default route (%d)\n",
436 * Fill in default values for all missing parameters.
439 static int __init ic_defaults(void)
442 * At this point we have no userspace running so need not
443 * claim locks on system_utsname
446 if (!ic_host_name_set)
447 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
449 if (root_server_addr == NONE)
450 root_server_addr = ic_servaddr;
452 if (ic_netmask == NONE) {
453 if (IN_CLASSA(ntohl(ic_myaddr)))
454 ic_netmask = htonl(IN_CLASSA_NET);
455 else if (IN_CLASSB(ntohl(ic_myaddr)))
456 ic_netmask = htonl(IN_CLASSB_NET);
457 else if (IN_CLASSC(ntohl(ic_myaddr)))
458 ic_netmask = htonl(IN_CLASSC_NET);
460 pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
464 printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
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 *sha, *tha; /* s for "source", t for "target" */
505 if (!net_eq(dev_net(dev), &init_net))
508 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
511 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
514 /* Basic sanity checks can be done without the lock. */
515 rarp = (struct arphdr *)skb_transport_header(skb);
517 /* If this test doesn't pass, it's not IP, or we should
520 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
523 /* If it's not a RARP reply, delete it. */
524 if (rarp->ar_op != htons(ARPOP_RREPLY))
527 /* If it's not Ethernet, delete it. */
528 if (rarp->ar_pro != htons(ETH_P_IP))
531 if (!pskb_may_pull(skb, arp_hdr_len(dev)))
534 /* OK, it is all there and looks valid, process... */
535 rarp = (struct arphdr *)skb_transport_header(skb);
536 rarp_ptr = (unsigned char *) (rarp + 1);
538 /* One reply at a time, please. */
539 spin_lock(&ic_recv_lock);
541 /* If we already have a reply, just drop the packet */
545 /* Find the ic_device that the packet arrived on */
547 while (d && d->dev != dev)
550 goto drop_unlock; /* should never happen */
552 /* 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,
659 * Initialize DHCP/BOOTP extension fields in the request.
662 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
667 ic_dhcp_init_options(u8 *options)
669 u8 mt = ((ic_servaddr == NONE)
670 ? DHCPDISCOVER : DHCPREQUEST);
674 #ifdef IPCONFIG_DEBUG
675 printk("DHCP: Sending message type %d\n", mt);
678 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
681 *e++ = 53; /* DHCP message type */
685 if (mt == DHCPREQUEST) {
686 *e++ = 54; /* Server ID (IP address) */
688 memcpy(e, &ic_servaddr, 4);
691 *e++ = 50; /* Requested IP address */
693 memcpy(e, &ic_myaddr, 4);
699 static const u8 ic_req_params[] = {
701 3, /* Default gateway */
704 15, /* Domain name */
707 40, /* NIS domain name */
710 *e++ = 55; /* Parameter request list */
711 *e++ = sizeof(ic_req_params);
712 memcpy(e, ic_req_params, sizeof(ic_req_params));
713 e += sizeof(ic_req_params);
715 if (ic_host_name_set) {
716 *e++ = 12; /* host-name */
717 len = strlen(utsname()->nodename);
719 memcpy(e, utsname()->nodename, len);
722 if (*vendor_class_identifier) {
723 pr_info("DHCP: sending class identifier \"%s\"\n",
724 vendor_class_identifier);
725 *e++ = 60; /* Class-identifier */
726 len = strlen(vendor_class_identifier);
728 memcpy(e, vendor_class_identifier, len);
733 *e++ = 255; /* End of the list */
736 #endif /* IPCONFIG_DHCP */
738 static void __init ic_bootp_init_ext(u8 *e)
740 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
742 *e++ = 1; /* Subnet mask request */
745 *e++ = 3; /* Default gateway request */
748 *e++ = 5; /* Name server request */
751 *e++ = 12; /* Host name request */
754 *e++ = 40; /* NIS Domain name request */
757 *e++ = 17; /* Boot path */
761 *e++ = 57; /* set extension buffer size for reply */
763 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
766 *e++ = 255; /* End of the list */
771 * Initialize the DHCP/BOOTP mechanism.
773 static inline void __init ic_bootp_init(void)
775 ic_nameservers_predef();
777 dev_add_pack(&bootp_packet_type);
782 * DHCP/BOOTP cleanup.
784 static inline void __init ic_bootp_cleanup(void)
786 dev_remove_pack(&bootp_packet_type);
791 * Send DHCP/BOOTP request to single interface.
793 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
795 struct net_device *dev = d->dev;
799 int hlen = LL_RESERVED_SPACE(dev);
800 int tlen = dev->needed_tailroom;
802 /* Allocate packet */
803 skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
807 skb_reserve(skb, hlen);
808 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
809 memset(b, 0, sizeof(struct bootp_pkt));
811 /* Construct IP header */
812 skb_reset_network_header(skb);
816 h->tot_len = htons(sizeof(struct bootp_pkt));
817 h->frag_off = htons(IP_DF);
819 h->protocol = IPPROTO_UDP;
820 h->daddr = htonl(INADDR_BROADCAST);
821 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
823 /* Construct UDP header */
824 b->udph.source = htons(68);
825 b->udph.dest = htons(67);
826 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
827 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
829 /* Construct DHCP/BOOTP header */
830 b->op = BOOTP_REQUEST;
831 if (dev->type < 256) /* check for false types */
832 b->htype = dev->type;
833 else if (dev->type == ARPHRD_FDDI)
834 b->htype = ARPHRD_ETHER;
836 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
837 b->htype = dev->type; /* can cause undefined behavior */
840 /* server_ip and your_ip address are both already zero per RFC2131 */
841 b->hlen = dev->addr_len;
842 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
843 b->secs = htons(jiffies_diff / HZ);
846 /* add DHCP options or BOOTP extensions */
848 if (ic_proto_enabled & IC_USE_DHCP)
849 ic_dhcp_init_options(b->exten);
852 ic_bootp_init_ext(b->exten);
854 /* Chain packet down the line... */
856 skb->protocol = htons(ETH_P_IP);
857 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
858 dev->broadcast, dev->dev_addr, skb->len) < 0) {
864 if (dev_queue_xmit(skb) < 0)
870 * Copy BOOTP-supplied string if not already set.
872 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
878 memcpy(dest, src, len);
885 * Process BOOTP extensions.
887 static void __init ic_do_bootp_ext(u8 *ext)
893 #ifdef IPCONFIG_DEBUG
896 printk("DHCP/BOOTP: Got extension %d:",*ext);
897 for (c=ext+2; c<ext+2+ext[1]; c++)
903 case 1: /* Subnet mask */
904 if (ic_netmask == NONE)
905 memcpy(&ic_netmask, ext+1, 4);
907 case 3: /* Default gateway */
908 if (ic_gateway == NONE)
909 memcpy(&ic_gateway, ext+1, 4);
911 case 6: /* DNS server */
913 if (servers > CONF_NAMESERVERS_MAX)
914 servers = CONF_NAMESERVERS_MAX;
915 for (i = 0; i < servers; i++) {
916 if (ic_nameservers[i] == NONE)
917 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
920 case 12: /* Host name */
921 ic_bootp_string(utsname()->nodename, ext+1, *ext,
923 ic_host_name_set = 1;
925 case 15: /* Domain name (DNS) */
926 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
928 case 17: /* Root path */
929 if (!root_server_path[0])
930 ic_bootp_string(root_server_path, ext+1, *ext,
931 sizeof(root_server_path));
933 case 26: /* Interface MTU */
934 memcpy(&mtu, ext+1, sizeof(mtu));
935 ic_dev_mtu = ntohs(mtu);
937 case 40: /* NIS Domain name (_not_ DNS) */
938 ic_bootp_string(utsname()->domainname, ext+1, *ext,
946 * Receive BOOTP reply.
948 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
955 if (!net_eq(dev_net(dev), &init_net))
958 /* Perform verifications before taking the lock. */
959 if (skb->pkt_type == PACKET_OTHERHOST)
962 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
965 if (!pskb_may_pull(skb,
966 sizeof(struct iphdr) +
967 sizeof(struct udphdr)))
970 b = (struct bootp_pkt *)skb_network_header(skb);
973 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
976 /* Fragments are not supported */
977 if (ip_is_fragment(h)) {
978 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
982 if (skb->len < ntohs(h->tot_len))
985 if (ip_fast_csum((char *) h, h->ihl))
988 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
991 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
994 len = ntohs(b->udph.len) - sizeof(struct udphdr);
995 ext_len = len - (sizeof(*b) -
996 sizeof(struct iphdr) -
997 sizeof(struct udphdr) -
1002 /* Ok the front looks good, make sure we can get at the rest. */
1003 if (!pskb_may_pull(skb, skb->len))
1006 b = (struct bootp_pkt *)skb_network_header(skb);
1009 /* One reply at a time, please. */
1010 spin_lock(&ic_recv_lock);
1012 /* If we already have a reply, just drop the packet */
1016 /* Find the ic_device that the packet arrived on */
1018 while (d && d->dev != dev)
1021 goto drop_unlock; /* should never happen */
1023 /* Is it a reply to our BOOTP request? */
1024 if (b->op != BOOTP_REPLY ||
1026 net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1031 /* Is it a reply for the device we are configuring? */
1032 if (b->xid != ic_dev_xid) {
1033 net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1037 /* Parse extensions */
1039 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1040 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1043 #ifdef IPCONFIG_DHCP
1044 if (ic_proto_enabled & IC_USE_DHCP) {
1045 __be32 server_id = NONE;
1049 while (ext < end && *ext != 0xff) {
1051 if (*opt == 0) /* Padding */
1057 case 53: /* Message type */
1061 case 54: /* Server ID (IP address) */
1063 memcpy(&server_id, opt + 2, 4);
1068 #ifdef IPCONFIG_DEBUG
1069 printk("DHCP: Got message type %d\n", mt);
1074 /* While in the process of accepting one offer,
1075 * ignore all others.
1077 if (ic_myaddr != NONE)
1080 /* Let's accept that offer. */
1081 ic_myaddr = b->your_ip;
1082 ic_servaddr = server_id;
1083 #ifdef IPCONFIG_DEBUG
1084 printk("DHCP: Offered address %pI4 by server %pI4\n",
1085 &ic_myaddr, &b->iph.saddr);
1087 /* The DHCP indicated server address takes
1088 * precedence over the bootp header one if
1089 * they are different.
1091 if ((server_id != NONE) &&
1092 (b->server_ip != server_id))
1093 b->server_ip = ic_servaddr;
1097 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1104 /* Urque. Forget it*/
1110 ic_dhcp_msgtype = mt;
1113 #endif /* IPCONFIG_DHCP */
1116 while (ext < end && *ext != 0xff) {
1118 if (*opt == 0) /* Padding */
1122 ic_do_bootp_ext(opt);
1126 /* We have a winner! */
1128 ic_myaddr = b->your_ip;
1129 ic_servaddr = b->server_ip;
1130 ic_addrservaddr = b->iph.saddr;
1131 if (ic_gateway == NONE && b->relay_ip)
1132 ic_gateway = b->relay_ip;
1133 if (ic_nameservers[0] == NONE)
1134 ic_nameservers[0] = ic_servaddr;
1135 ic_got_reply = IC_BOOTP;
1138 /* Show's over. Nothing to see here. */
1139 spin_unlock(&ic_recv_lock);
1142 /* Throw the packet out. */
1153 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1156 #ifdef IPCONFIG_DYNAMIC
1158 static int __init ic_dynamic(void)
1161 struct ic_device *d;
1162 unsigned long start_jiffies, timeout, jiff;
1163 int do_bootp = ic_proto_have_if & IC_BOOTP;
1164 int do_rarp = ic_proto_have_if & IC_RARP;
1167 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1168 * This routine gets only called when some pieces of information
1169 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1171 if (!ic_proto_enabled) {
1172 pr_err("IP-Config: Incomplete network configuration information\n");
1176 #ifdef IPCONFIG_BOOTP
1177 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1178 pr_err("DHCP/BOOTP: No suitable device found\n");
1180 #ifdef IPCONFIG_RARP
1181 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1182 pr_err("RARP: No suitable device found\n");
1185 if (!ic_proto_have_if)
1186 /* Error message already printed */
1192 #ifdef IPCONFIG_BOOTP
1196 #ifdef IPCONFIG_RARP
1202 * Send requests and wait, until we get an answer. This loop
1203 * seems to be a terrible waste of CPU time, but actually there is
1204 * only one process running at all, so we don't need to use any
1205 * scheduler functions.
1206 * [Actually we could now, but the nothing else running note still
1209 pr_notice("Sending %s%s%s requests .",
1211 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1212 (do_bootp && do_rarp) ? " and " : "",
1213 do_rarp ? "RARP" : "");
1215 start_jiffies = jiffies;
1217 retries = CONF_SEND_RETRIES;
1218 get_random_bytes(&timeout, sizeof(timeout));
1219 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1221 /* Track the device we are configuring */
1222 ic_dev_xid = d->xid;
1224 #ifdef IPCONFIG_BOOTP
1225 if (do_bootp && (d->able & IC_BOOTP))
1226 ic_bootp_send_if(d, jiffies - start_jiffies);
1228 #ifdef IPCONFIG_RARP
1229 if (do_rarp && (d->able & IC_RARP))
1233 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1234 while (time_before(jiffies, jiff) && !ic_got_reply)
1235 schedule_timeout_uninterruptible(1);
1236 #ifdef IPCONFIG_DHCP
1237 /* DHCP isn't done until we get a DHCPACK. */
1238 if ((ic_got_reply & IC_BOOTP) &&
1239 (ic_proto_enabled & IC_USE_DHCP) &&
1240 ic_dhcp_msgtype != DHCPACK) {
1245 #endif /* IPCONFIG_DHCP */
1256 pr_cont(" timed out!\n");
1262 timeout = timeout CONF_TIMEOUT_MULT;
1263 if (timeout > CONF_TIMEOUT_MAX)
1264 timeout = CONF_TIMEOUT_MAX;
1269 #ifdef IPCONFIG_BOOTP
1273 #ifdef IPCONFIG_RARP
1278 if (!ic_got_reply) {
1283 printk("IP-Config: Got %s answer from %pI4, ",
1284 ((ic_got_reply & IC_RARP) ? "RARP"
1285 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1287 pr_cont("my address is %pI4\n", &ic_myaddr);
1292 #endif /* IPCONFIG_DYNAMIC */
1294 #ifdef CONFIG_PROC_FS
1296 static int pnp_seq_show(struct seq_file *seq, void *v)
1300 if (ic_proto_used & IC_PROTO)
1301 seq_printf(seq, "#PROTO: %s\n",
1302 (ic_proto_used & IC_RARP) ? "RARP"
1303 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1305 seq_puts(seq, "#MANUAL\n");
1309 "domain %s\n", ic_domain);
1310 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1311 if (ic_nameservers[i] != NONE)
1312 seq_printf(seq, "nameserver %pI4\n",
1313 &ic_nameservers[i]);
1315 if (ic_servaddr != NONE)
1316 seq_printf(seq, "bootserver %pI4\n",
1321 static int pnp_seq_open(struct inode *indoe, struct file *file)
1323 return single_open(file, pnp_seq_show, NULL);
1326 static const struct file_operations pnp_seq_fops = {
1327 .owner = THIS_MODULE,
1328 .open = pnp_seq_open,
1330 .llseek = seq_lseek,
1331 .release = single_release,
1333 #endif /* CONFIG_PROC_FS */
1336 * Extract IP address from the parameter string if needed. Note that we
1337 * need to have root_server_addr set _before_ IPConfig gets called as it
1340 __be32 __init root_nfs_parse_addr(char *name)
1347 while (octets < 4) {
1348 while (*cp >= '0' && *cp <= '9')
1350 if (cp == cq || cp - cq > 3)
1352 if (*cp == '.' || octets == 3)
1358 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1361 addr = in_aton(name);
1362 memmove(name, cp, strlen(cp) + 1);
1369 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1371 static int __init wait_for_devices(void)
1375 for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1376 struct net_device *dev;
1380 for_each_netdev(&init_net, dev) {
1381 if (ic_is_init_dev(dev)) {
1395 * IP Autoconfig dispatcher.
1398 static int __init ip_auto_config(void)
1401 #ifdef IPCONFIG_DYNAMIC
1402 int retries = CONF_OPEN_RETRIES;
1407 #ifdef CONFIG_PROC_FS
1408 proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1409 #endif /* CONFIG_PROC_FS */
1414 DBG(("IP-Config: Entered.\n"));
1415 #ifdef IPCONFIG_DYNAMIC
1418 /* Wait for devices to appear */
1419 err = wait_for_devices();
1423 /* Setup all network devices */
1424 err = ic_open_devs();
1428 /* Give drivers a chance to settle */
1429 msleep(CONF_POST_OPEN);
1432 * If the config information is insufficient (e.g., our IP address or
1433 * IP address of the boot server is missing or we have multiple network
1434 * interfaces and no default was set), use BOOTP or RARP to get the
1437 if (ic_myaddr == NONE ||
1438 #ifdef CONFIG_ROOT_NFS
1439 (root_server_addr == NONE &&
1440 ic_servaddr == NONE &&
1441 ROOT_DEV == Root_NFS) ||
1443 ic_first_dev->next) {
1444 #ifdef IPCONFIG_DYNAMIC
1445 if (ic_dynamic() < 0) {
1449 * I don't know why, but sometimes the
1450 * eepro100 driver (at least) gets upset and
1451 * doesn't work the first time it's opened.
1452 * But then if you close it and reopen it, it
1453 * works just fine. So we need to try that at
1454 * least once before giving up.
1456 * Also, if the root will be NFS-mounted, we
1457 * have nowhere to go if DHCP fails. So we
1458 * just have to keep trying forever.
1462 #ifdef CONFIG_ROOT_NFS
1463 if (ROOT_DEV == Root_NFS) {
1464 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1470 pr_err("IP-Config: Reopening network devices...\n");
1474 /* Oh, well. At least we tried. */
1475 pr_err("IP-Config: Auto-configuration of network failed\n");
1478 #else /* !DYNAMIC */
1479 pr_err("IP-Config: Incomplete network configuration information\n");
1482 #endif /* IPCONFIG_DYNAMIC */
1484 /* Device selected manually or only one device -> use it */
1485 ic_dev = ic_first_dev->dev;
1488 addr = root_nfs_parse_addr(root_server_path);
1489 if (root_server_addr == NONE)
1490 root_server_addr = addr;
1493 * Use defaults wherever applicable.
1495 if (ic_defaults() < 0)
1499 * Close all network devices except the device we've
1500 * autoconfigured and set up routes.
1503 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1507 * Record which protocol was actually used.
1509 #ifdef IPCONFIG_DYNAMIC
1510 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1513 #ifndef IPCONFIG_SILENT
1515 * Clue in the operator.
1517 pr_info("IP-Config: Complete:\n");
1519 pr_info(" device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1520 ic_dev->name, ic_dev->addr_len, ic_dev->dev_addr,
1521 &ic_myaddr, &ic_netmask, &ic_gateway);
1522 pr_info(" host=%s, domain=%s, nis-domain=%s\n",
1523 utsname()->nodename, ic_domain, utsname()->domainname);
1524 pr_info(" bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1525 &ic_servaddr, &root_server_addr, root_server_path);
1527 pr_cont(", mtu=%d", ic_dev_mtu);
1528 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1529 if (ic_nameservers[i] != NONE) {
1530 pr_info(" nameserver%u=%pI4",
1531 i, &ic_nameservers[i]);
1534 for (i++; i < CONF_NAMESERVERS_MAX; i++)
1535 if (ic_nameservers[i] != NONE)
1536 pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1538 #endif /* !SILENT */
1543 late_initcall(ip_auto_config);
1547 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1548 * command line parameter. See Documentation/filesystems/nfs/nfsroot.txt.
1550 static int __init ic_proto_name(char *name)
1552 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1555 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1558 #ifdef CONFIG_IP_PNP_DHCP
1559 else if (!strcmp(name, "dhcp")) {
1560 ic_proto_enabled &= ~IC_RARP;
1564 #ifdef CONFIG_IP_PNP_BOOTP
1565 else if (!strcmp(name, "bootp")) {
1566 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1570 #ifdef CONFIG_IP_PNP_RARP
1571 else if (!strcmp(name, "rarp")) {
1572 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1576 #ifdef IPCONFIG_DYNAMIC
1577 else if (!strcmp(name, "both")) {
1578 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1585 static int __init ip_auto_config_setup(char *addrs)
1590 ic_set_manually = 1;
1594 * If any dhcp, bootp etc options are set, leave autoconfig on
1595 * and skip the below static IP processing.
1597 if (ic_proto_name(addrs))
1600 /* If no static IP is given, turn off autoconfig and bail. */
1602 strcmp(addrs, "off") == 0 ||
1603 strcmp(addrs, "none") == 0) {
1608 ic_nameservers_predef();
1610 /* Parse string for static IP assignment. */
1613 if ((cp = strchr(ip, ':')))
1615 if (strlen(ip) > 0) {
1616 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1619 if ((ic_myaddr = in_aton(ip)) == ANY)
1623 if ((ic_servaddr = in_aton(ip)) == ANY)
1627 if ((ic_gateway = in_aton(ip)) == ANY)
1631 if ((ic_netmask = in_aton(ip)) == ANY)
1635 if ((dp = strchr(ip, '.'))) {
1637 strlcpy(utsname()->domainname, dp,
1638 sizeof(utsname()->domainname));
1640 strlcpy(utsname()->nodename, ip,
1641 sizeof(utsname()->nodename));
1642 ic_host_name_set = 1;
1645 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1648 if (ic_proto_name(ip) == 0 &&
1649 ic_myaddr == NONE) {
1654 if (CONF_NAMESERVERS_MAX >= 1) {
1655 ic_nameservers[0] = in_aton(ip);
1656 if (ic_nameservers[0] == ANY)
1657 ic_nameservers[0] = NONE;
1661 if (CONF_NAMESERVERS_MAX >= 2) {
1662 ic_nameservers[1] = in_aton(ip);
1663 if (ic_nameservers[1] == ANY)
1664 ic_nameservers[1] = NONE;
1675 __setup("ip=", ip_auto_config_setup);
1677 static int __init nfsaddrs_config_setup(char *addrs)
1679 return ip_auto_config_setup(addrs);
1681 __setup("nfsaddrs=", nfsaddrs_config_setup);
1683 static int __init vendor_class_identifier_setup(char *addrs)
1685 if (strlcpy(vendor_class_identifier, addrs,
1686 sizeof(vendor_class_identifier))
1687 >= sizeof(vendor_class_identifier))
1688 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"",
1689 vendor_class_identifier);
1692 __setup("dhcpclass=", vendor_class_identifier_setup);