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_INTER_TIMEOUT (HZ) /* Inter-device timeout: 1 second */
89 #define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
90 #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
91 #define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
92 #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
93 #define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
94 - '3' from resolv.h */
96 #define NONE cpu_to_be32(INADDR_NONE)
97 #define ANY cpu_to_be32(INADDR_ANY)
100 * Public IP configuration
103 /* This is used by platforms which might be able to set the ipconfig
104 * variables using firmware environment vars. If this is set, it will
105 * ignore such firmware variables.
107 int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
109 static int ic_enable __initdata; /* IP config enabled? */
111 /* Protocol choice */
112 int ic_proto_enabled __initdata = 0
113 #ifdef IPCONFIG_BOOTP
116 #ifdef CONFIG_IP_PNP_DHCP
124 static int ic_host_name_set __initdata; /* Host name set by us? */
126 __be32 ic_myaddr = NONE; /* My IP address */
127 static __be32 ic_netmask = NONE; /* Netmask for local subnet */
128 __be32 ic_gateway = NONE; /* Gateway IP address */
130 __be32 ic_addrservaddr = NONE; /* IP Address of the IP addresses'server */
132 __be32 ic_servaddr = NONE; /* Boot server IP address */
134 __be32 root_server_addr = NONE; /* Address of NFS server */
135 u8 root_server_path[256] = { 0, }; /* Path to mount as root */
137 /* vendor class identifier */
138 static char vendor_class_identifier[253] __initdata;
140 #if defined(CONFIG_IP_PNP_DHCP)
141 static char dhcp_client_identifier[253] __initdata;
144 /* Persistent data: */
146 static int ic_proto_used; /* Protocol used, if any */
147 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
148 static u8 ic_domain[64]; /* DNS (not NIS) domain name */
154 /* Name of user-selected boot device */
155 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
157 /* Protocols supported by available interfaces */
158 static int ic_proto_have_if __initdata;
160 /* MTU for boot device */
161 static int ic_dev_mtu __initdata;
163 #ifdef IPCONFIG_DYNAMIC
164 static DEFINE_SPINLOCK(ic_recv_lock);
165 static volatile int ic_got_reply __initdata; /* Proto(s) that replied */
168 static int ic_dhcp_msgtype __initdata; /* DHCP msg type received */
177 struct ic_device *next;
178 struct net_device *dev;
179 unsigned short flags;
184 static struct ic_device *ic_first_dev __initdata; /* List of open device */
185 static struct net_device *ic_dev __initdata; /* Selected device */
187 static bool __init ic_is_init_dev(struct net_device *dev)
189 if (dev->flags & IFF_LOOPBACK)
191 return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
192 (!(dev->flags & IFF_LOOPBACK) &&
193 (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
194 strncmp(dev->name, "dummy", 5));
197 static int __init ic_open_devs(void)
199 struct ic_device *d, **last;
200 struct net_device *dev;
201 unsigned short oflags;
202 unsigned long start, next_msg;
204 last = &ic_first_dev;
207 /* bring loopback and DSA master network devices up first */
208 for_each_netdev(&init_net, dev) {
209 if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
211 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
212 pr_err("IP-Config: Failed to open %s\n", dev->name);
215 for_each_netdev(&init_net, dev) {
216 if (ic_is_init_dev(dev)) {
221 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
222 dev->name, dev->mtu);
223 if (!(dev->flags & IFF_NOARP))
225 able &= ic_proto_enabled;
226 if (ic_proto_enabled && !able)
229 if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
230 pr_err("IP-Config: Failed to open %s\n",
234 if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
244 get_random_bytes(&d->xid, sizeof(__be32));
247 ic_proto_have_if |= able;
248 pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
249 dev->name, able, d->xid);
253 /* no point in waiting if we could not bring up at least one device */
257 /* wait for a carrier on at least one device */
259 next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
260 while (time_before(jiffies, start +
261 msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
264 for_each_netdev(&init_net, dev)
265 if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
270 if (time_before(jiffies, next_msg))
273 elapsed = jiffies_to_msecs(jiffies - start);
274 wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
275 pr_info("Waiting up to %d more seconds for network.\n", wait);
276 next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
284 if (user_dev_name[0])
285 pr_err("IP-Config: Device `%s' not found\n",
288 pr_err("IP-Config: No network devices available\n");
294 static void __init ic_close_devs(void)
296 struct ic_device *d, *next;
297 struct net_device *dev;
304 if (dev != ic_dev && !netdev_uses_dsa(dev)) {
305 pr_debug("IP-Config: Downing %s\n", dev->name);
306 dev_change_flags(dev, d->flags);
314 * Interface to various network functions.
318 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
320 sin->sin_family = AF_INET;
321 sin->sin_addr.s_addr = addr;
322 sin->sin_port = port;
325 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
329 mm_segment_t oldfs = get_fs();
331 res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
336 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
340 mm_segment_t oldfs = get_fs();
342 res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
347 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
351 mm_segment_t oldfs = get_fs();
353 res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
359 * Set up interface addresses and routes.
362 static int __init ic_setup_if(void)
365 struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
368 memset(&ir, 0, sizeof(ir));
369 strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
370 set_sockaddr(sin, ic_myaddr, 0);
371 if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
372 pr_err("IP-Config: Unable to set interface address (%d)\n",
376 set_sockaddr(sin, ic_netmask, 0);
377 if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
378 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
382 set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
383 if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
384 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
388 /* Handle the case where we need non-standard MTU on the boot link (a network
389 * using jumbo frames, for instance). If we can't set the mtu, don't error
390 * out, we'll try to muddle along.
392 if (ic_dev_mtu != 0) {
393 strcpy(ir.ifr_name, ic_dev->name);
394 ir.ifr_mtu = ic_dev_mtu;
395 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
396 pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
402 static int __init ic_setup_routes(void)
404 /* No need to setup device routes, only the default route... */
406 if (ic_gateway != NONE) {
410 memset(&rm, 0, sizeof(rm));
411 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
412 pr_err("IP-Config: Gateway not on directly connected network\n");
415 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
416 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
417 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
418 rm.rt_flags = RTF_UP | RTF_GATEWAY;
419 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
420 pr_err("IP-Config: Cannot add default route (%d)\n",
430 * Fill in default values for all missing parameters.
433 static int __init ic_defaults(void)
436 * At this point we have no userspace running so need not
437 * claim locks on system_utsname
440 if (!ic_host_name_set)
441 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
443 if (root_server_addr == NONE)
444 root_server_addr = ic_servaddr;
446 if (ic_netmask == NONE) {
447 if (IN_CLASSA(ntohl(ic_myaddr)))
448 ic_netmask = htonl(IN_CLASSA_NET);
449 else if (IN_CLASSB(ntohl(ic_myaddr)))
450 ic_netmask = htonl(IN_CLASSB_NET);
451 else if (IN_CLASSC(ntohl(ic_myaddr)))
452 ic_netmask = htonl(IN_CLASSC_NET);
454 pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
458 pr_notice("IP-Config: Guessing netmask %pI4\n",
471 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
473 static struct packet_type rarp_packet_type __initdata = {
474 .type = cpu_to_be16(ETH_P_RARP),
475 .func = ic_rarp_recv,
478 static inline void __init ic_rarp_init(void)
480 dev_add_pack(&rarp_packet_type);
483 static inline void __init ic_rarp_cleanup(void)
485 dev_remove_pack(&rarp_packet_type);
489 * Process received RARP packet.
492 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
495 unsigned char *rarp_ptr;
497 unsigned char *tha; /* t for "target" */
500 if (!net_eq(dev_net(dev), &init_net))
503 skb = skb_share_check(skb, GFP_ATOMIC);
507 if (!pskb_may_pull(skb, sizeof(struct arphdr)))
510 /* Basic sanity checks can be done without the lock. */
511 rarp = (struct arphdr *)skb_transport_header(skb);
513 /* If this test doesn't pass, it's not IP, or we should
516 if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
519 /* If it's not a RARP reply, delete it. */
520 if (rarp->ar_op != htons(ARPOP_RREPLY))
523 /* If it's not Ethernet, delete it. */
524 if (rarp->ar_pro != htons(ETH_P_IP))
527 if (!pskb_may_pull(skb, arp_hdr_len(dev)))
530 /* OK, it is all there and looks valid, process... */
531 rarp = (struct arphdr *)skb_transport_header(skb);
532 rarp_ptr = (unsigned char *) (rarp + 1);
534 /* One reply at a time, please. */
535 spin_lock(&ic_recv_lock);
537 /* If we already have a reply, just drop the packet */
541 /* Find the ic_device that the packet arrived on */
543 while (d && d->dev != dev)
546 goto drop_unlock; /* should never happen */
548 /* Extract variable-width fields */
549 rarp_ptr += dev->addr_len;
550 memcpy(&sip, rarp_ptr, 4);
553 rarp_ptr += dev->addr_len;
554 memcpy(&tip, rarp_ptr, 4);
556 /* Discard packets which are not meant for us. */
557 if (memcmp(tha, dev->dev_addr, dev->addr_len))
560 /* Discard packets which are not from specified server. */
561 if (ic_servaddr != NONE && ic_servaddr != sip)
564 /* We have a winner! */
566 if (ic_myaddr == NONE)
569 ic_addrservaddr = sip;
570 ic_got_reply = IC_RARP;
573 /* Show's over. Nothing to see here. */
574 spin_unlock(&ic_recv_lock);
577 /* Throw the packet out. */
584 * Send RARP request packet over a single interface.
586 static void __init ic_rarp_send_if(struct ic_device *d)
588 struct net_device *dev = d->dev;
589 arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
590 dev->dev_addr, dev->dev_addr);
595 * Predefine Nameservers
597 static inline void __init ic_nameservers_predef(void)
601 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
602 ic_nameservers[i] = NONE;
606 * DHCP/BOOTP support.
609 #ifdef IPCONFIG_BOOTP
611 struct bootp_pkt { /* BOOTP packet format */
612 struct iphdr iph; /* IP header */
613 struct udphdr udph; /* UDP header */
614 u8 op; /* 1=request, 2=reply */
615 u8 htype; /* HW address type */
616 u8 hlen; /* HW address length */
617 u8 hops; /* Used only by gateways */
618 __be32 xid; /* Transaction ID */
619 __be16 secs; /* Seconds since we started */
620 __be16 flags; /* Just what it says */
621 __be32 client_ip; /* Client's IP address if known */
622 __be32 your_ip; /* Assigned IP address */
623 __be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
624 __be32 relay_ip; /* IP address of BOOTP relay */
625 u8 hw_addr[16]; /* Client's HW address */
626 u8 serv_name[64]; /* Server host name */
627 u8 boot_file[128]; /* Name of boot file */
628 u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
632 #define BOOTP_REQUEST 1
633 #define BOOTP_REPLY 2
635 /* DHCP message types */
636 #define DHCPDISCOVER 1
638 #define DHCPREQUEST 3
639 #define DHCPDECLINE 4
642 #define DHCPRELEASE 7
645 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
647 static struct packet_type bootp_packet_type __initdata = {
648 .type = cpu_to_be16(ETH_P_IP),
649 .func = ic_bootp_recv,
652 static __be32 ic_dev_xid; /* Device under configuration */
655 * Initialize DHCP/BOOTP extension fields in the request.
658 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
663 ic_dhcp_init_options(u8 *options)
665 u8 mt = ((ic_servaddr == NONE)
666 ? DHCPDISCOVER : DHCPREQUEST);
670 pr_debug("DHCP: Sending message type %d\n", mt);
672 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
675 *e++ = 53; /* DHCP message type */
679 if (mt == DHCPREQUEST) {
680 *e++ = 54; /* Server ID (IP address) */
682 memcpy(e, &ic_servaddr, 4);
685 *e++ = 50; /* Requested IP address */
687 memcpy(e, &ic_myaddr, 4);
693 static const u8 ic_req_params[] = {
695 3, /* Default gateway */
698 15, /* Domain name */
701 40, /* NIS domain name */
704 *e++ = 55; /* Parameter request list */
705 *e++ = sizeof(ic_req_params);
706 memcpy(e, ic_req_params, sizeof(ic_req_params));
707 e += sizeof(ic_req_params);
709 if (ic_host_name_set) {
710 *e++ = 12; /* host-name */
711 len = strlen(utsname()->nodename);
713 memcpy(e, utsname()->nodename, len);
716 if (*vendor_class_identifier) {
717 pr_info("DHCP: sending class identifier \"%s\"\n",
718 vendor_class_identifier);
719 *e++ = 60; /* Class-identifier */
720 len = strlen(vendor_class_identifier);
722 memcpy(e, vendor_class_identifier, len);
725 len = strlen(dhcp_client_identifier + 1);
726 /* the minimum length of identifier is 2, include 1 byte type,
727 * and can not be larger than the length of options
729 if (len >= 1 && len < 312 - (e - options) - 1) {
732 memcpy(e, dhcp_client_identifier, len + 1);
737 *e++ = 255; /* End of the list */
740 #endif /* IPCONFIG_DHCP */
742 static void __init ic_bootp_init_ext(u8 *e)
744 memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
746 *e++ = 1; /* Subnet mask request */
749 *e++ = 3; /* Default gateway request */
752 *e++ = 5; /* Name server request */
755 *e++ = 12; /* Host name request */
758 *e++ = 40; /* NIS Domain name request */
761 *e++ = 17; /* Boot path */
765 *e++ = 57; /* set extension buffer size for reply */
767 *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
770 *e++ = 255; /* End of the list */
775 * Initialize the DHCP/BOOTP mechanism.
777 static inline void __init ic_bootp_init(void)
779 ic_nameservers_predef();
781 dev_add_pack(&bootp_packet_type);
786 * DHCP/BOOTP cleanup.
788 static inline void __init ic_bootp_cleanup(void)
790 dev_remove_pack(&bootp_packet_type);
795 * Send DHCP/BOOTP request to single interface.
797 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
799 struct net_device *dev = d->dev;
803 int hlen = LL_RESERVED_SPACE(dev);
804 int tlen = dev->needed_tailroom;
806 /* Allocate packet */
807 skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
811 skb_reserve(skb, hlen);
812 b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
813 memset(b, 0, sizeof(struct bootp_pkt));
815 /* Construct IP header */
816 skb_reset_network_header(skb);
820 h->tot_len = htons(sizeof(struct bootp_pkt));
821 h->frag_off = htons(IP_DF);
823 h->protocol = IPPROTO_UDP;
824 h->daddr = htonl(INADDR_BROADCAST);
825 h->check = ip_fast_csum((unsigned char *) h, h->ihl);
827 /* Construct UDP header */
828 b->udph.source = htons(68);
829 b->udph.dest = htons(67);
830 b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
831 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
833 /* Construct DHCP/BOOTP header */
834 b->op = BOOTP_REQUEST;
835 if (dev->type < 256) /* check for false types */
836 b->htype = dev->type;
837 else if (dev->type == ARPHRD_FDDI)
838 b->htype = ARPHRD_ETHER;
840 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
842 b->htype = dev->type; /* can cause undefined behavior */
845 /* server_ip and your_ip address are both already zero per RFC2131 */
846 b->hlen = dev->addr_len;
847 memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
848 b->secs = htons(jiffies_diff / HZ);
851 /* add DHCP options or BOOTP extensions */
853 if (ic_proto_enabled & IC_USE_DHCP)
854 ic_dhcp_init_options(b->exten);
857 ic_bootp_init_ext(b->exten);
859 /* Chain packet down the line... */
861 skb->protocol = htons(ETH_P_IP);
862 if (dev_hard_header(skb, dev, ntohs(skb->protocol),
863 dev->broadcast, dev->dev_addr, skb->len) < 0) {
869 if (dev_queue_xmit(skb) < 0)
875 * Copy BOOTP-supplied string if not already set.
877 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
883 memcpy(dest, src, len);
890 * Process BOOTP extensions.
892 static void __init ic_do_bootp_ext(u8 *ext)
900 pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
901 for (c=ext+2; c<ext+2+ext[1]; c++)
902 pr_debug(" %02x", *c);
906 case 1: /* Subnet mask */
907 if (ic_netmask == NONE)
908 memcpy(&ic_netmask, ext+1, 4);
910 case 3: /* Default gateway */
911 if (ic_gateway == NONE)
912 memcpy(&ic_gateway, ext+1, 4);
914 case 6: /* DNS server */
916 if (servers > CONF_NAMESERVERS_MAX)
917 servers = CONF_NAMESERVERS_MAX;
918 for (i = 0; i < servers; i++) {
919 if (ic_nameservers[i] == NONE)
920 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
923 case 12: /* Host name */
924 ic_bootp_string(utsname()->nodename, ext+1, *ext,
926 ic_host_name_set = 1;
928 case 15: /* Domain name (DNS) */
929 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
931 case 17: /* Root path */
932 if (!root_server_path[0])
933 ic_bootp_string(root_server_path, ext+1, *ext,
934 sizeof(root_server_path));
936 case 26: /* Interface MTU */
937 memcpy(&mtu, ext+1, sizeof(mtu));
938 ic_dev_mtu = ntohs(mtu);
940 case 40: /* NIS Domain name (_not_ DNS) */
941 ic_bootp_string(utsname()->domainname, ext+1, *ext,
949 * Receive BOOTP reply.
951 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
958 if (!net_eq(dev_net(dev), &init_net))
961 /* Perform verifications before taking the lock. */
962 if (skb->pkt_type == PACKET_OTHERHOST)
965 skb = skb_share_check(skb, GFP_ATOMIC);
969 if (!pskb_may_pull(skb,
970 sizeof(struct iphdr) +
971 sizeof(struct udphdr)))
974 b = (struct bootp_pkt *)skb_network_header(skb);
977 if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
980 /* Fragments are not supported */
981 if (ip_is_fragment(h)) {
982 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
986 if (skb->len < ntohs(h->tot_len))
989 if (ip_fast_csum((char *) h, h->ihl))
992 if (b->udph.source != htons(67) || b->udph.dest != htons(68))
995 if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
998 len = ntohs(b->udph.len) - sizeof(struct udphdr);
999 ext_len = len - (sizeof(*b) -
1000 sizeof(struct iphdr) -
1001 sizeof(struct udphdr) -
1006 /* Ok the front looks good, make sure we can get at the rest. */
1007 if (!pskb_may_pull(skb, skb->len))
1010 b = (struct bootp_pkt *)skb_network_header(skb);
1013 /* One reply at a time, please. */
1014 spin_lock(&ic_recv_lock);
1016 /* If we already have a reply, just drop the packet */
1020 /* Find the ic_device that the packet arrived on */
1022 while (d && d->dev != dev)
1025 goto drop_unlock; /* should never happen */
1027 /* Is it a reply to our BOOTP request? */
1028 if (b->op != BOOTP_REPLY ||
1030 net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1035 /* Is it a reply for the device we are configuring? */
1036 if (b->xid != ic_dev_xid) {
1037 net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1041 /* Parse extensions */
1043 !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1044 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1047 #ifdef IPCONFIG_DHCP
1048 if (ic_proto_enabled & IC_USE_DHCP) {
1049 __be32 server_id = NONE;
1053 while (ext < end && *ext != 0xff) {
1055 if (*opt == 0) /* Padding */
1061 case 53: /* Message type */
1065 case 54: /* Server ID (IP address) */
1067 memcpy(&server_id, opt + 2, 4);
1072 pr_debug("DHCP: Got message type %d\n", mt);
1076 /* While in the process of accepting one offer,
1077 * ignore all others.
1079 if (ic_myaddr != NONE)
1082 /* Let's accept that offer. */
1083 ic_myaddr = b->your_ip;
1084 ic_servaddr = server_id;
1085 pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1086 &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 #ifdef IPCONFIG_BOOTP
1222 /* Track the device we are configuring */
1223 ic_dev_xid = d->xid;
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 pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1284 ((ic_got_reply & IC_RARP) ? "RARP"
1285 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1286 &ic_addrservaddr, &ic_myaddr);
1291 #endif /* IPCONFIG_DYNAMIC */
1293 #ifdef CONFIG_PROC_FS
1295 static int pnp_seq_show(struct seq_file *seq, void *v)
1299 if (ic_proto_used & IC_PROTO)
1300 seq_printf(seq, "#PROTO: %s\n",
1301 (ic_proto_used & IC_RARP) ? "RARP"
1302 : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1304 seq_puts(seq, "#MANUAL\n");
1308 "domain %s\n", ic_domain);
1309 for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1310 if (ic_nameservers[i] != NONE)
1311 seq_printf(seq, "nameserver %pI4\n",
1312 &ic_nameservers[i]);
1314 if (ic_servaddr != NONE)
1315 seq_printf(seq, "bootserver %pI4\n",
1320 static int pnp_seq_open(struct inode *indoe, struct file *file)
1322 return single_open(file, pnp_seq_show, NULL);
1325 static const struct file_operations pnp_seq_fops = {
1326 .owner = THIS_MODULE,
1327 .open = pnp_seq_open,
1329 .llseek = seq_lseek,
1330 .release = single_release,
1332 #endif /* CONFIG_PROC_FS */
1335 * Extract IP address from the parameter string if needed. Note that we
1336 * need to have root_server_addr set _before_ IPConfig gets called as it
1339 __be32 __init root_nfs_parse_addr(char *name)
1346 while (octets < 4) {
1347 while (*cp >= '0' && *cp <= '9')
1349 if (cp == cq || cp - cq > 3)
1351 if (*cp == '.' || octets == 3)
1357 if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1360 addr = in_aton(name);
1361 memmove(name, cp, strlen(cp) + 1);
1368 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1370 static int __init wait_for_devices(void)
1374 for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1375 struct net_device *dev;
1379 for_each_netdev(&init_net, dev) {
1380 if (ic_is_init_dev(dev)) {
1394 * IP Autoconfig dispatcher.
1397 static int __init ip_auto_config(void)
1400 #ifdef IPCONFIG_DYNAMIC
1401 int retries = CONF_OPEN_RETRIES;
1406 #ifdef CONFIG_PROC_FS
1407 proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1408 #endif /* CONFIG_PROC_FS */
1413 pr_debug("IP-Config: Entered.\n");
1414 #ifdef IPCONFIG_DYNAMIC
1417 /* Wait for devices to appear */
1418 err = wait_for_devices();
1422 /* Setup all network devices */
1423 err = ic_open_devs();
1427 /* Give drivers a chance to settle */
1428 msleep(CONF_POST_OPEN);
1431 * If the config information is insufficient (e.g., our IP address or
1432 * IP address of the boot server is missing or we have multiple network
1433 * interfaces and no default was set), use BOOTP or RARP to get the
1436 if (ic_myaddr == NONE ||
1437 #ifdef CONFIG_ROOT_NFS
1438 (root_server_addr == NONE &&
1439 ic_servaddr == NONE &&
1440 ROOT_DEV == Root_NFS) ||
1442 ic_first_dev->next) {
1443 #ifdef IPCONFIG_DYNAMIC
1444 if (ic_dynamic() < 0) {
1448 * I don't know why, but sometimes the
1449 * eepro100 driver (at least) gets upset and
1450 * doesn't work the first time it's opened.
1451 * But then if you close it and reopen it, it
1452 * works just fine. So we need to try that at
1453 * least once before giving up.
1455 * Also, if the root will be NFS-mounted, we
1456 * have nowhere to go if DHCP fails. So we
1457 * just have to keep trying forever.
1461 #ifdef CONFIG_ROOT_NFS
1462 if (ROOT_DEV == Root_NFS) {
1463 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1469 pr_err("IP-Config: Reopening network devices...\n");
1473 /* Oh, well. At least we tried. */
1474 pr_err("IP-Config: Auto-configuration of network failed\n");
1477 #else /* !DYNAMIC */
1478 pr_err("IP-Config: Incomplete network configuration information\n");
1481 #endif /* IPCONFIG_DYNAMIC */
1483 /* Device selected manually or only one device -> use it */
1484 ic_dev = ic_first_dev->dev;
1487 addr = root_nfs_parse_addr(root_server_path);
1488 if (root_server_addr == NONE)
1489 root_server_addr = addr;
1492 * Use defaults wherever applicable.
1494 if (ic_defaults() < 0)
1498 * Close all network devices except the device we've
1499 * autoconfigured and set up routes.
1502 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1506 * Record which protocol was actually used.
1508 #ifdef IPCONFIG_DYNAMIC
1509 ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1512 #ifndef IPCONFIG_SILENT
1514 * Clue in the operator.
1516 pr_info("IP-Config: Complete:\n");
1518 pr_info(" device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1519 ic_dev->name, ic_dev->addr_len, ic_dev->dev_addr,
1520 &ic_myaddr, &ic_netmask, &ic_gateway);
1521 pr_info(" host=%s, domain=%s, nis-domain=%s\n",
1522 utsname()->nodename, ic_domain, utsname()->domainname);
1523 pr_info(" bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1524 &ic_servaddr, &root_server_addr, root_server_path);
1526 pr_cont(", mtu=%d", ic_dev_mtu);
1527 for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1528 if (ic_nameservers[i] != NONE) {
1529 pr_cont(" nameserver%u=%pI4",
1530 i, &ic_nameservers[i]);
1533 for (i++; i < CONF_NAMESERVERS_MAX; i++)
1534 if (ic_nameservers[i] != NONE)
1535 pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1537 #endif /* !SILENT */
1542 late_initcall(ip_auto_config);
1546 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1547 * command line parameter. See Documentation/filesystems/nfs/nfsroot.txt.
1549 static int __init ic_proto_name(char *name)
1551 if (!strcmp(name, "on") || !strcmp(name, "any")) {
1554 if (!strcmp(name, "off") || !strcmp(name, "none")) {
1557 #ifdef CONFIG_IP_PNP_DHCP
1558 else if (!strncmp(name, "dhcp", 4)) {
1561 ic_proto_enabled &= ~IC_RARP;
1562 client_id = strstr(name, "dhcp,");
1566 client_id = client_id + 5;
1567 v = strchr(client_id, ',');
1571 if (kstrtou8(client_id, 0, dhcp_client_identifier))
1572 pr_debug("DHCP: Invalid client identifier type\n");
1573 strncpy(dhcp_client_identifier + 1, v + 1, 251);
1579 #ifdef CONFIG_IP_PNP_BOOTP
1580 else if (!strcmp(name, "bootp")) {
1581 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1585 #ifdef CONFIG_IP_PNP_RARP
1586 else if (!strcmp(name, "rarp")) {
1587 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1591 #ifdef IPCONFIG_DYNAMIC
1592 else if (!strcmp(name, "both")) {
1593 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1600 static int __init ip_auto_config_setup(char *addrs)
1605 ic_set_manually = 1;
1609 * If any dhcp, bootp etc options are set, leave autoconfig on
1610 * and skip the below static IP processing.
1612 if (ic_proto_name(addrs))
1615 /* If no static IP is given, turn off autoconfig and bail. */
1617 strcmp(addrs, "off") == 0 ||
1618 strcmp(addrs, "none") == 0) {
1623 ic_nameservers_predef();
1625 /* Parse string for static IP assignment. */
1628 if ((cp = strchr(ip, ':')))
1630 if (strlen(ip) > 0) {
1631 pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1634 if ((ic_myaddr = in_aton(ip)) == ANY)
1638 if ((ic_servaddr = in_aton(ip)) == ANY)
1642 if ((ic_gateway = in_aton(ip)) == ANY)
1646 if ((ic_netmask = in_aton(ip)) == ANY)
1650 if ((dp = strchr(ip, '.'))) {
1652 strlcpy(utsname()->domainname, dp,
1653 sizeof(utsname()->domainname));
1655 strlcpy(utsname()->nodename, ip,
1656 sizeof(utsname()->nodename));
1657 ic_host_name_set = 1;
1660 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1663 if (ic_proto_name(ip) == 0 &&
1664 ic_myaddr == NONE) {
1669 if (CONF_NAMESERVERS_MAX >= 1) {
1670 ic_nameservers[0] = in_aton(ip);
1671 if (ic_nameservers[0] == ANY)
1672 ic_nameservers[0] = NONE;
1676 if (CONF_NAMESERVERS_MAX >= 2) {
1677 ic_nameservers[1] = in_aton(ip);
1678 if (ic_nameservers[1] == ANY)
1679 ic_nameservers[1] = NONE;
1690 __setup("ip=", ip_auto_config_setup);
1692 static int __init nfsaddrs_config_setup(char *addrs)
1694 return ip_auto_config_setup(addrs);
1696 __setup("nfsaddrs=", nfsaddrs_config_setup);
1698 static int __init vendor_class_identifier_setup(char *addrs)
1700 if (strlcpy(vendor_class_identifier, addrs,
1701 sizeof(vendor_class_identifier))
1702 >= sizeof(vendor_class_identifier))
1703 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1704 vendor_class_identifier);
1707 __setup("dhcpclass=", vendor_class_identifier_setup);