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;
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 while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
267 for_each_netdev(&init_net, dev)
268 if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
279 if (user_dev_name[0])
280 pr_err("IP-Config: Device `%s' not found\n",
283 pr_err("IP-Config: No network devices available\n");
289 static void __init ic_close_devs(void)
291 struct ic_device *d, *next;
292 struct net_device *dev;
300 DBG(("IP-Config: Downing %s\n", dev->name));
301 dev_change_flags(dev, d->flags);
309 * Interface to various network functions.
313 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
315 sin->sin_family = AF_INET;
316 sin->sin_addr.s_addr = addr;
317 sin->sin_port = port;
320 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
324 mm_segment_t oldfs = get_fs();
326 res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
331 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
335 mm_segment_t oldfs = get_fs();
337 res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
342 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
346 mm_segment_t oldfs = get_fs();
348 res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
354 * Set up interface addresses and routes.
357 static int __init ic_setup_if(void)
360 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
363 memset(&ir, 0, sizeof(ir));
364 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
365 set_sockaddr(sin, ic_myaddr, 0);
366 if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
367 pr_err("IP-Config: Unable to set interface address (%d)\n",
371 set_sockaddr(sin, ic_netmask, 0);
372 if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
373 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
377 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
378 if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
379 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
383 /* Handle the case where we need non-standard MTU on the boot link (a network
384 * using jumbo frames, for instance). If we can't set the mtu, don't error
385 * out, we'll try to muddle along.
387 if (ic_dev_mtu != 0) {
388 strcpy(ir.ifr_name, ic_dev->name);
389 ir.ifr_mtu = ic_dev_mtu;
390 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
391 pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
397 static int __init ic_setup_routes(void)
399 /* No need to setup device routes, only the default route... */
401 if (ic_gateway != NONE) {
405 memset(&rm, 0, sizeof(rm));
406 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
407 pr_err("IP-Config: Gateway not on directly connected network\n");
410 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
411 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
412 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
413 rm.rt_flags = RTF_UP | RTF_GATEWAY;
414 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
415 pr_err("IP-Config: Cannot add default route (%d)\n",
425 * Fill in default values for all missing parameters.
428 static int __init ic_defaults(void)
431 * At this point we have no userspace running so need not
432 * claim locks on system_utsname
435 if (!ic_host_name_set)
436 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
438 if (root_server_addr == NONE)
439 root_server_addr = ic_servaddr;
441 if (ic_netmask == NONE) {
442 if (IN_CLASSA(ntohl(ic_myaddr)))
443 ic_netmask = htonl(IN_CLASSA_NET);
444 else if (IN_CLASSB(ntohl(ic_myaddr)))
445 ic_netmask = htonl(IN_CLASSB_NET);
446 else if (IN_CLASSC(ntohl(ic_myaddr)))
447 ic_netmask = htonl(IN_CLASSC_NET);
449 pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
453 printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
465 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
467 static struct packet_type rarp_packet_type __initdata = {
468 .type = cpu_to_be16(ETH_P_RARP),
469 .func = ic_rarp_recv,
472 static inline void __init ic_rarp_init(void)
474 dev_add_pack(&rarp_packet_type);
477 static inline void __init ic_rarp_cleanup(void)
479 dev_remove_pack(&rarp_packet_type);
483 * Process received RARP packet.
486 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
489 unsigned char *rarp_ptr;
491 unsigned char *sha, *tha; /* s for "source", t for "target" */
494 if (!net_eq(dev_net(dev), &init_net))
497 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
500 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
503 /* Basic sanity checks can be done without the lock. */
504 rarp = (struct arphdr *)skb_transport_header(skb);
506 /* If this test doesn't pass, it's not IP, or we should
509 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
512 /* If it's not a RARP reply, delete it. */
513 if (rarp->ar_op != htons(ARPOP_RREPLY))
516 /* If it's not Ethernet, delete it. */
517 if (rarp->ar_pro != htons(ETH_P_IP))
520 if (!pskb_may_pull(skb, arp_hdr_len(dev)))
523 /* OK, it is all there and looks valid, process... */
524 rarp = (struct arphdr *)skb_transport_header(skb);
525 rarp_ptr = (unsigned char *) (rarp + 1);
527 /* One reply at a time, please. */
528 spin_lock(&ic_recv_lock);
530 /* If we already have a reply, just drop the packet */
534 /* Find the ic_device that the packet arrived on */
536 while (d && d->dev != dev)
539 goto drop_unlock; /* should never happen */
541 /* Extract variable-width fields */
543 rarp_ptr += dev->addr_len;
544 memcpy(&sip, rarp_ptr, 4);
547 rarp_ptr += dev->addr_len;
548 memcpy(&tip, rarp_ptr, 4);
550 /* Discard packets which are not meant for us. */
551 if (memcmp(tha, dev->dev_addr, dev->addr_len))
554 /* Discard packets which are not from specified server. */
555 if (ic_servaddr != NONE && ic_servaddr != sip)
558 /* We have a winner! */
560 if (ic_myaddr == NONE)
563 ic_addrservaddr = sip;
564 ic_got_reply = IC_RARP;
567 /* Show's over. Nothing to see here. */
568 spin_unlock(&ic_recv_lock);
571 /* Throw the packet out. */
578 * Send RARP request packet over a single interface.
580 static void __init ic_rarp_send_if(struct ic_device *d)
582 struct net_device *dev = d->dev;
583 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
584 dev->dev_addr, dev->dev_addr);
589 * Predefine Nameservers
591 static inline void __init ic_nameservers_predef(void)
595 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
596 ic_nameservers[i] = NONE;
600 * DHCP/BOOTP support.
603 #ifdef IPCONFIG_BOOTP
605 struct bootp_pkt { /* BOOTP packet format */
606 struct iphdr iph; /* IP header */
607 struct udphdr udph; /* UDP header */
608 u8 op; /* 1=request, 2=reply */
609 u8 htype; /* HW address type */
610 u8 hlen; /* HW address length */
611 u8 hops; /* Used only by gateways */
612 __be32 xid; /* Transaction ID */
613 __be16 secs; /* Seconds since we started */
614 __be16 flags; /* Just what it says */
615 __be32 client_ip; /* Client's IP address if known */
616 __be32 your_ip; /* Assigned IP address */
617 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
618 __be32 relay_ip; /* IP address of BOOTP relay */
619 u8 hw_addr[16]; /* Client's HW address */
620 u8 serv_name[64]; /* Server host name */
621 u8 boot_file[128]; /* Name of boot file */
622 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
626 #define BOOTP_REQUEST 1
627 #define BOOTP_REPLY 2
629 /* DHCP message types */
630 #define DHCPDISCOVER 1
632 #define DHCPREQUEST 3
633 #define DHCPDECLINE 4
636 #define DHCPRELEASE 7
639 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
641 static struct packet_type bootp_packet_type __initdata = {
642 .type = cpu_to_be16(ETH_P_IP),
643 .func = ic_bootp_recv,
648 * Initialize DHCP/BOOTP extension fields in the request.
651 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
656 ic_dhcp_init_options(u8 *options)
658 u8 mt = ((ic_servaddr == NONE)
659 ? DHCPDISCOVER : DHCPREQUEST);
663 #ifdef IPCONFIG_DEBUG
664 printk("DHCP: Sending message type %d\n", mt);
667 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
670 *e++ = 53; /* DHCP message type */
674 if (mt == DHCPREQUEST) {
675 *e++ = 54; /* Server ID (IP address) */
677 memcpy(e, &ic_servaddr, 4);
680 *e++ = 50; /* Requested IP address */
682 memcpy(e, &ic_myaddr, 4);
688 static const u8 ic_req_params[] = {
690 3, /* Default gateway */
693 15, /* Domain name */
696 40, /* NIS domain name */
699 *e++ = 55; /* Parameter request list */
700 *e++ = sizeof(ic_req_params);
701 memcpy(e, ic_req_params, sizeof(ic_req_params));
702 e += sizeof(ic_req_params);
704 if (ic_host_name_set) {
705 *e++ = 12; /* host-name */
706 len = strlen(utsname()->nodename);
708 memcpy(e, utsname()->nodename, len);
711 if (*vendor_class_identifier) {
712 pr_info("DHCP: sending class identifier \"%s\"\n",
713 vendor_class_identifier);
714 *e++ = 60; /* Class-identifier */
715 len = strlen(vendor_class_identifier);
717 memcpy(e, vendor_class_identifier, len);
722 *e++ = 255; /* End of the list */
725 #endif /* IPCONFIG_DHCP */
727 static void __init ic_bootp_init_ext(u8 *e)
729 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
731 *e++ = 1; /* Subnet mask request */
734 *e++ = 3; /* Default gateway request */
737 *e++ = 5; /* Name server request */
740 *e++ = 12; /* Host name request */
743 *e++ = 40; /* NIS Domain name request */
746 *e++ = 17; /* Boot path */
750 *e++ = 57; /* set extension buffer size for reply */
752 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
755 *e++ = 255; /* End of the list */
760 * Initialize the DHCP/BOOTP mechanism.
762 static inline void __init ic_bootp_init(void)
764 ic_nameservers_predef();
766 dev_add_pack(&bootp_packet_type);
771 * DHCP/BOOTP cleanup.
773 static inline void __init ic_bootp_cleanup(void)
775 dev_remove_pack(&bootp_packet_type);
780 * Send DHCP/BOOTP request to single interface.
782 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
784 struct net_device *dev = d->dev;
788 int hlen = LL_RESERVED_SPACE(dev);
789 int tlen = dev->needed_tailroom;
791 /* Allocate packet */
792 skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
796 skb_reserve(skb, hlen);
797 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
798 memset(b, 0, sizeof(struct bootp_pkt));
800 /* Construct IP header */
801 skb_reset_network_header(skb);
805 h->tot_len = htons(sizeof(struct bootp_pkt));
806 h->frag_off = htons(IP_DF);
808 h->protocol = IPPROTO_UDP;
809 h->daddr = htonl(INADDR_BROADCAST);
810 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
812 /* Construct UDP header */
813 b->udph.source = htons(68);
814 b->udph.dest = htons(67);
815 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
816 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
818 /* Construct DHCP/BOOTP header */
819 b->op = BOOTP_REQUEST;
820 if (dev->type < 256) /* check for false types */
821 b->htype = dev->type;
822 else if (dev->type == ARPHRD_FDDI)
823 b->htype = ARPHRD_ETHER;
825 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
826 b->htype = dev->type; /* can cause undefined behavior */
829 /* server_ip and your_ip address are both already zero per RFC2131 */
830 b->hlen = dev->addr_len;
831 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
832 b->secs = htons(jiffies_diff / HZ);
835 /* add DHCP options or BOOTP extensions */
837 if (ic_proto_enabled & IC_USE_DHCP)
838 ic_dhcp_init_options(b->exten);
841 ic_bootp_init_ext(b->exten);
843 /* Chain packet down the line... */
845 skb->protocol = htons(ETH_P_IP);
846 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
847 dev->broadcast, dev->dev_addr, skb->len) < 0) {
853 if (dev_queue_xmit(skb) < 0)
859 * Copy BOOTP-supplied string if not already set.
861 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
867 memcpy(dest, src, len);
874 * Process BOOTP extensions.
876 static void __init ic_do_bootp_ext(u8 *ext)
882 #ifdef IPCONFIG_DEBUG
885 printk("DHCP/BOOTP: Got extension %d:",*ext);
886 for (c=ext+2; c<ext+2+ext[1]; c++)
892 case 1: /* Subnet mask */
893 if (ic_netmask == NONE)
894 memcpy(&ic_netmask, ext+1, 4);
896 case 3: /* Default gateway */
897 if (ic_gateway == NONE)
898 memcpy(&ic_gateway, ext+1, 4);
900 case 6: /* DNS server */
902 if (servers > CONF_NAMESERVERS_MAX)
903 servers = CONF_NAMESERVERS_MAX;
904 for (i = 0; i < servers; i++) {
905 if (ic_nameservers[i] == NONE)
906 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
909 case 12: /* Host name */
910 ic_bootp_string(utsname()->nodename, ext+1, *ext,
912 ic_host_name_set = 1;
914 case 15: /* Domain name (DNS) */
915 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
917 case 17: /* Root path */
918 if (!root_server_path[0])
919 ic_bootp_string(root_server_path, ext+1, *ext,
920 sizeof(root_server_path));
922 case 26: /* Interface MTU */
923 memcpy(&mtu, ext+1, sizeof(mtu));
924 ic_dev_mtu = ntohs(mtu);
926 case 40: /* NIS Domain name (_not_ DNS) */
927 ic_bootp_string(utsname()->domainname, ext+1, *ext,
935 * Receive BOOTP reply.
937 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
944 if (!net_eq(dev_net(dev), &init_net))
947 /* Perform verifications before taking the lock. */
948 if (skb->pkt_type == PACKET_OTHERHOST)
951 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
954 if (!pskb_may_pull(skb,
955 sizeof(struct iphdr) +
956 sizeof(struct udphdr)))
959 b = (struct bootp_pkt *)skb_network_header(skb);
962 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
965 /* Fragments are not supported */
966 if (ip_is_fragment(h)) {
967 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
971 if (skb->len < ntohs(h->tot_len))
974 if (ip_fast_csum((char *) h, h->ihl))
977 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
980 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
983 len = ntohs(b->udph.len) - sizeof(struct udphdr);
984 ext_len = len - (sizeof(*b) -
985 sizeof(struct iphdr) -
986 sizeof(struct udphdr) -
991 /* Ok the front looks good, make sure we can get at the rest. */
992 if (!pskb_may_pull(skb, skb->len))
995 b = (struct bootp_pkt *)skb_network_header(skb);
998 /* One reply at a time, please. */
999 spin_lock(&ic_recv_lock);
1001 /* If we already have a reply, just drop the packet */
1005 /* Find the ic_device that the packet arrived on */
1007 while (d && d->dev != dev)
1010 goto drop_unlock; /* should never happen */
1012 /* Is it a reply to our BOOTP request? */
1013 if (b->op != BOOTP_REPLY ||
1015 net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1020 /* Is it a reply for the device we are configuring? */
1021 if (b->xid != ic_dev_xid) {
1022 net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1026 /* Parse extensions */
1028 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1029 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1032 #ifdef IPCONFIG_DHCP
1033 if (ic_proto_enabled & IC_USE_DHCP) {
1034 __be32 server_id = NONE;
1038 while (ext < end && *ext != 0xff) {
1040 if (*opt == 0) /* Padding */
1046 case 53: /* Message type */
1050 case 54: /* Server ID (IP address) */
1052 memcpy(&server_id, opt + 2, 4);
1057 #ifdef IPCONFIG_DEBUG
1058 printk("DHCP: Got message type %d\n", mt);
1063 /* While in the process of accepting one offer,
1064 * ignore all others.
1066 if (ic_myaddr != NONE)
1069 /* Let's accept that offer. */
1070 ic_myaddr = b->your_ip;
1071 ic_servaddr = server_id;
1072 #ifdef IPCONFIG_DEBUG
1073 printk("DHCP: Offered address %pI4 by server %pI4\n",
1074 &ic_myaddr, &b->iph.saddr);
1076 /* The DHCP indicated server address takes
1077 * precedence over the bootp header one if
1078 * they are different.
1080 if ((server_id != NONE) &&
1081 (b->server_ip != server_id))
1082 b->server_ip = ic_servaddr;
1086 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1093 /* Urque. Forget it*/
1099 ic_dhcp_msgtype = mt;
1102 #endif /* IPCONFIG_DHCP */
1105 while (ext < end && *ext != 0xff) {
1107 if (*opt == 0) /* Padding */
1111 ic_do_bootp_ext(opt);
1115 /* We have a winner! */
1117 ic_myaddr = b->your_ip;
1118 ic_servaddr = b->server_ip;
1119 ic_addrservaddr = b->iph.saddr;
1120 if (ic_gateway == NONE && b->relay_ip)
1121 ic_gateway = b->relay_ip;
1122 if (ic_nameservers[0] == NONE)
1123 ic_nameservers[0] = ic_servaddr;
1124 ic_got_reply = IC_BOOTP;
1127 /* Show's over. Nothing to see here. */
1128 spin_unlock(&ic_recv_lock);
1131 /* Throw the packet out. */
1142 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1145 #ifdef IPCONFIG_DYNAMIC
1147 static int __init ic_dynamic(void)
1150 struct ic_device *d;
1151 unsigned long start_jiffies, timeout, jiff;
1152 int do_bootp = ic_proto_have_if & IC_BOOTP;
1153 int do_rarp = ic_proto_have_if & IC_RARP;
1156 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1157 * This routine gets only called when some pieces of information
1158 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1160 if (!ic_proto_enabled) {
1161 pr_err("IP-Config: Incomplete network configuration information\n");
1165 #ifdef IPCONFIG_BOOTP
1166 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1167 pr_err("DHCP/BOOTP: No suitable device found\n");
1169 #ifdef IPCONFIG_RARP
1170 if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1171 pr_err("RARP: No suitable device found\n");
1174 if (!ic_proto_have_if)
1175 /* Error message already printed */
1181 #ifdef IPCONFIG_BOOTP
1185 #ifdef IPCONFIG_RARP
1191 * Send requests and wait, until we get an answer. This loop
1192 * seems to be a terrible waste of CPU time, but actually there is
1193 * only one process running at all, so we don't need to use any
1194 * scheduler functions.
1195 * [Actually we could now, but the nothing else running note still
1198 pr_notice("Sending %s%s%s requests .",
1200 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1201 (do_bootp && do_rarp) ? " and " : "",
1202 do_rarp ? "RARP" : "");
1204 start_jiffies = jiffies;
1206 retries = CONF_SEND_RETRIES;
1207 get_random_bytes(&timeout, sizeof(timeout));
1208 timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1210 /* Track the device we are configuring */
1211 ic_dev_xid = d->xid;
1213 #ifdef IPCONFIG_BOOTP
1214 if (do_bootp && (d->able & IC_BOOTP))
1215 ic_bootp_send_if(d, jiffies - start_jiffies);
1217 #ifdef IPCONFIG_RARP
1218 if (do_rarp && (d->able & IC_RARP))
1222 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1223 while (time_before(jiffies, jiff) && !ic_got_reply)
1224 schedule_timeout_uninterruptible(1);
1225 #ifdef IPCONFIG_DHCP
1226 /* DHCP isn't done until we get a DHCPACK. */
1227 if ((ic_got_reply & IC_BOOTP) &&
1228 (ic_proto_enabled & IC_USE_DHCP) &&
1229 ic_dhcp_msgtype != DHCPACK) {
1234 #endif /* IPCONFIG_DHCP */
1245 pr_cont(" timed out!\n");
1251 timeout = timeout CONF_TIMEOUT_MULT;
1252 if (timeout > CONF_TIMEOUT_MAX)
1253 timeout = CONF_TIMEOUT_MAX;
1258 #ifdef IPCONFIG_BOOTP
1262 #ifdef IPCONFIG_RARP
1267 if (!ic_got_reply) {
1272 printk("IP-Config: Got %s answer from %pI4, ",
1273 ((ic_got_reply & IC_RARP) ? "RARP"
1274 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1276 pr_cont("my address is %pI4\n", &ic_myaddr);
1281 #endif /* IPCONFIG_DYNAMIC */
1283 #ifdef CONFIG_PROC_FS
1285 static int pnp_seq_show(struct seq_file *seq, void *v)
1289 if (ic_proto_used & IC_PROTO)
1290 seq_printf(seq, "#PROTO: %s\n",
1291 (ic_proto_used & IC_RARP) ? "RARP"
1292 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1294 seq_puts(seq, "#MANUAL\n");
1298 "domain %s\n", ic_domain);
1299 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1300 if (ic_nameservers[i] != NONE)
1301 seq_printf(seq, "nameserver %pI4\n",
1302 &ic_nameservers[i]);
1304 if (ic_servaddr != NONE)
1305 seq_printf(seq, "bootserver %pI4\n",
1310 static int pnp_seq_open(struct inode *indoe, struct file *file)
1312 return single_open(file, pnp_seq_show, NULL);
1315 static const struct file_operations pnp_seq_fops = {
1316 .owner = THIS_MODULE,
1317 .open = pnp_seq_open,
1319 .llseek = seq_lseek,
1320 .release = single_release,
1322 #endif /* CONFIG_PROC_FS */
1325 * Extract IP address from the parameter string if needed. Note that we
1326 * need to have root_server_addr set _before_ IPConfig gets called as it
1329 __be32 __init root_nfs_parse_addr(char *name)
1336 while (octets < 4) {
1337 while (*cp >= '0' && *cp <= '9')
1339 if (cp == cq || cp - cq > 3)
1341 if (*cp == '.' || octets == 3)
1347 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1350 addr = in_aton(name);
1351 memmove(name, cp, strlen(cp) + 1);
1358 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1360 static int __init wait_for_devices(void)
1364 for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1365 struct net_device *dev;
1369 for_each_netdev(&init_net, dev) {
1370 if (ic_is_init_dev(dev)) {
1384 * IP Autoconfig dispatcher.
1387 static int __init ip_auto_config(void)
1390 #ifdef IPCONFIG_DYNAMIC
1391 int retries = CONF_OPEN_RETRIES;
1396 #ifdef CONFIG_PROC_FS
1397 proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1398 #endif /* CONFIG_PROC_FS */
1403 DBG(("IP-Config: Entered.\n"));
1404 #ifdef IPCONFIG_DYNAMIC
1407 /* Wait for devices to appear */
1408 err = wait_for_devices();
1412 /* Setup all network devices */
1413 err = ic_open_devs();
1417 /* Give drivers a chance to settle */
1418 msleep(CONF_POST_OPEN);
1421 * If the config information is insufficient (e.g., our IP address or
1422 * IP address of the boot server is missing or we have multiple network
1423 * interfaces and no default was set), use BOOTP or RARP to get the
1426 if (ic_myaddr == NONE ||
1427 #ifdef CONFIG_ROOT_NFS
1428 (root_server_addr == NONE &&
1429 ic_servaddr == NONE &&
1430 ROOT_DEV == Root_NFS) ||
1432 ic_first_dev->next) {
1433 #ifdef IPCONFIG_DYNAMIC
1434 if (ic_dynamic() < 0) {
1438 * I don't know why, but sometimes the
1439 * eepro100 driver (at least) gets upset and
1440 * doesn't work the first time it's opened.
1441 * But then if you close it and reopen it, it
1442 * works just fine. So we need to try that at
1443 * least once before giving up.
1445 * Also, if the root will be NFS-mounted, we
1446 * have nowhere to go if DHCP fails. So we
1447 * just have to keep trying forever.
1451 #ifdef CONFIG_ROOT_NFS
1452 if (ROOT_DEV == Root_NFS) {
1453 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1459 pr_err("IP-Config: Reopening network devices...\n");
1463 /* Oh, well. At least we tried. */
1464 pr_err("IP-Config: Auto-configuration of network failed\n");
1467 #else /* !DYNAMIC */
1468 pr_err("IP-Config: Incomplete network configuration information\n");
1471 #endif /* IPCONFIG_DYNAMIC */
1473 /* Device selected manually or only one device -> use it */
1474 ic_dev = ic_first_dev->dev;
1477 addr = root_nfs_parse_addr(root_server_path);
1478 if (root_server_addr == NONE)
1479 root_server_addr = addr;
1482 * Use defaults wherever applicable.
1484 if (ic_defaults() < 0)
1488 * Close all network devices except the device we've
1489 * autoconfigured and set up routes.
1492 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1496 * Record which protocol was actually used.
1498 #ifdef IPCONFIG_DYNAMIC
1499 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1502 #ifndef IPCONFIG_SILENT
1504 * Clue in the operator.
1506 pr_info("IP-Config: Complete:\n");
1508 pr_info(" device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1509 ic_dev->name, ic_dev->addr_len, ic_dev->dev_addr,
1510 &ic_myaddr, &ic_netmask, &ic_gateway);
1511 pr_info(" host=%s, domain=%s, nis-domain=%s\n",
1512 utsname()->nodename, ic_domain, utsname()->domainname);
1513 pr_info(" bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1514 &ic_servaddr, &root_server_addr, root_server_path);
1516 pr_cont(", mtu=%d", ic_dev_mtu);
1517 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1518 if (ic_nameservers[i] != NONE) {
1519 pr_info(" nameserver%u=%pI4",
1520 i, &ic_nameservers[i]);
1523 for (i++; i < CONF_NAMESERVERS_MAX; i++)
1524 if (ic_nameservers[i] != NONE)
1525 pr_cont(", nameserver%u=%pI4\n", i, &ic_nameservers[i]);
1526 #endif /* !SILENT */
1531 late_initcall(ip_auto_config);
1535 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1536 * command line parameter. See Documentation/filesystems/nfs/nfsroot.txt.
1538 static int __init ic_proto_name(char *name)
1540 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1543 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1546 #ifdef CONFIG_IP_PNP_DHCP
1547 else if (!strcmp(name, "dhcp")) {
1548 ic_proto_enabled &= ~IC_RARP;
1552 #ifdef CONFIG_IP_PNP_BOOTP
1553 else if (!strcmp(name, "bootp")) {
1554 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1558 #ifdef CONFIG_IP_PNP_RARP
1559 else if (!strcmp(name, "rarp")) {
1560 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1564 #ifdef IPCONFIG_DYNAMIC
1565 else if (!strcmp(name, "both")) {
1566 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1573 static int __init ip_auto_config_setup(char *addrs)
1578 ic_set_manually = 1;
1582 * If any dhcp, bootp etc options are set, leave autoconfig on
1583 * and skip the below static IP processing.
1585 if (ic_proto_name(addrs))
1588 /* If no static IP is given, turn off autoconfig and bail. */
1590 strcmp(addrs, "off") == 0 ||
1591 strcmp(addrs, "none") == 0) {
1596 ic_nameservers_predef();
1598 /* Parse string for static IP assignment. */
1601 if ((cp = strchr(ip, ':')))
1603 if (strlen(ip) > 0) {
1604 DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1607 if ((ic_myaddr = in_aton(ip)) == ANY)
1611 if ((ic_servaddr = in_aton(ip)) == ANY)
1615 if ((ic_gateway = in_aton(ip)) == ANY)
1619 if ((ic_netmask = in_aton(ip)) == ANY)
1623 if ((dp = strchr(ip, '.'))) {
1625 strlcpy(utsname()->domainname, dp,
1626 sizeof(utsname()->domainname));
1628 strlcpy(utsname()->nodename, ip,
1629 sizeof(utsname()->nodename));
1630 ic_host_name_set = 1;
1633 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1636 if (ic_proto_name(ip) == 0 &&
1637 ic_myaddr == NONE) {
1642 if (CONF_NAMESERVERS_MAX >= 1) {
1643 ic_nameservers[0] = in_aton(ip);
1644 if (ic_nameservers[0] == ANY)
1645 ic_nameservers[0] = NONE;
1649 if (CONF_NAMESERVERS_MAX >= 2) {
1650 ic_nameservers[1] = in_aton(ip);
1651 if (ic_nameservers[1] == ANY)
1652 ic_nameservers[1] = NONE;
1663 __setup("ip=", ip_auto_config_setup);
1665 static int __init nfsaddrs_config_setup(char *addrs)
1667 return ip_auto_config_setup(addrs);
1669 __setup("nfsaddrs=", nfsaddrs_config_setup);
1671 static int __init vendor_class_identifier_setup(char *addrs)
1673 if (strlcpy(vendor_class_identifier, addrs,
1674 sizeof(vendor_class_identifier))
1675 >= sizeof(vendor_class_identifier))
1676 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"",
1677 vendor_class_identifier);
1680 __setup("dhcpclass=", vendor_class_identifier_setup);