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_servaddr
= NONE
; /* Boot server IP address */
141 __be32 root_server_addr
= NONE
; /* Address of NFS server */
142 u8 root_server_path
[256] = { 0, }; /* Path to mount as root */
144 __be32 ic_dev_xid
; /* Device under configuration */
146 /* vendor class identifier */
147 static char vendor_class_identifier
[253] __initdata
;
149 /* Persistent data: */
151 static int ic_proto_used
; /* Protocol used, if any */
152 static __be32 ic_nameservers
[CONF_NAMESERVERS_MAX
]; /* DNS Server IP addresses */
153 static u8 ic_domain
[64]; /* DNS (not NIS) domain name */
159 /* Name of user-selected boot device */
160 static char user_dev_name
[IFNAMSIZ
] __initdata
= { 0, };
162 /* Protocols supported by available interfaces */
163 static int ic_proto_have_if __initdata
= 0;
165 /* MTU for boot device */
166 static int ic_dev_mtu __initdata
= 0;
168 #ifdef IPCONFIG_DYNAMIC
169 static DEFINE_SPINLOCK(ic_recv_lock
);
170 static volatile int ic_got_reply __initdata
= 0; /* Proto(s) that replied */
173 static int ic_dhcp_msgtype __initdata
= 0; /* DHCP msg type received */
182 struct ic_device
*next
;
183 struct net_device
*dev
;
184 unsigned short flags
;
189 static struct ic_device
*ic_first_dev __initdata
= NULL
;/* List of open device */
190 static struct net_device
*ic_dev __initdata
= NULL
; /* Selected device */
192 static bool __init
ic_is_init_dev(struct net_device
*dev
)
194 if (dev
->flags
& IFF_LOOPBACK
)
196 return user_dev_name
[0] ? !strcmp(dev
->name
, user_dev_name
) :
197 (!(dev
->flags
& IFF_LOOPBACK
) &&
198 (dev
->flags
& (IFF_POINTOPOINT
|IFF_BROADCAST
)) &&
199 strncmp(dev
->name
, "dummy", 5));
202 static int __init
ic_open_devs(void)
204 struct ic_device
*d
, **last
;
205 struct net_device
*dev
;
206 unsigned short oflags
;
209 last
= &ic_first_dev
;
212 /* bring loopback device up first */
213 for_each_netdev(&init_net
, dev
) {
214 if (!(dev
->flags
& IFF_LOOPBACK
))
216 if (dev_change_flags(dev
, dev
->flags
| IFF_UP
) < 0)
217 pr_err("IP-Config: Failed to open %s\n", dev
->name
);
220 for_each_netdev(&init_net
, dev
) {
221 if (ic_is_init_dev(dev
)) {
226 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small",
227 dev
->name
, dev
->mtu
);
228 if (!(dev
->flags
& IFF_NOARP
))
230 able
&= ic_proto_enabled
;
231 if (ic_proto_enabled
&& !able
)
234 if (dev_change_flags(dev
, oflags
| IFF_UP
) < 0) {
235 pr_err("IP-Config: Failed to open %s\n",
239 if (!(d
= kmalloc(sizeof(struct ic_device
), GFP_KERNEL
))) {
249 get_random_bytes(&d
->xid
, sizeof(__be32
));
252 ic_proto_have_if
|= able
;
253 DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
254 dev
->name
, able
, d
->xid
));
258 /* no point in waiting if we could not bring up at least one device */
262 /* wait for a carrier on at least one device */
264 while (jiffies
- start
< msecs_to_jiffies(CONF_CARRIER_TIMEOUT
)) {
265 for_each_netdev(&init_net
, dev
)
266 if (ic_is_init_dev(dev
) && netif_carrier_ok(dev
))
277 if (user_dev_name
[0])
278 pr_err("IP-Config: Device `%s' not found\n",
281 pr_err("IP-Config: No network devices available\n");
287 static void __init
ic_close_devs(void)
289 struct ic_device
*d
, *next
;
290 struct net_device
*dev
;
298 DBG(("IP-Config: Downing %s\n", dev
->name
));
299 dev_change_flags(dev
, d
->flags
);
307 * Interface to various network functions.
311 set_sockaddr(struct sockaddr_in
*sin
, __be32 addr
, __be16 port
)
313 sin
->sin_family
= AF_INET
;
314 sin
->sin_addr
.s_addr
= addr
;
315 sin
->sin_port
= port
;
318 static int __init
ic_devinet_ioctl(unsigned int cmd
, struct ifreq
*arg
)
322 mm_segment_t oldfs
= get_fs();
324 res
= devinet_ioctl(&init_net
, cmd
, (struct ifreq __user
*) arg
);
329 static int __init
ic_dev_ioctl(unsigned int cmd
, struct ifreq
*arg
)
333 mm_segment_t oldfs
= get_fs();
335 res
= dev_ioctl(&init_net
, cmd
, (struct ifreq __user
*) arg
);
340 static int __init
ic_route_ioctl(unsigned int cmd
, struct rtentry
*arg
)
344 mm_segment_t oldfs
= get_fs();
346 res
= ip_rt_ioctl(&init_net
, cmd
, (void __user
*) arg
);
352 * Set up interface addresses and routes.
355 static int __init
ic_setup_if(void)
358 struct sockaddr_in
*sin
= (void *) &ir
.ifr_ifru
.ifru_addr
;
361 memset(&ir
, 0, sizeof(ir
));
362 strcpy(ir
.ifr_ifrn
.ifrn_name
, ic_dev
->name
);
363 set_sockaddr(sin
, ic_myaddr
, 0);
364 if ((err
= ic_devinet_ioctl(SIOCSIFADDR
, &ir
)) < 0) {
365 pr_err("IP-Config: Unable to set interface address (%d)\n",
369 set_sockaddr(sin
, ic_netmask
, 0);
370 if ((err
= ic_devinet_ioctl(SIOCSIFNETMASK
, &ir
)) < 0) {
371 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
375 set_sockaddr(sin
, ic_myaddr
| ~ic_netmask
, 0);
376 if ((err
= ic_devinet_ioctl(SIOCSIFBRDADDR
, &ir
)) < 0) {
377 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
381 /* Handle the case where we need non-standard MTU on the boot link (a network
382 * using jumbo frames, for instance). If we can't set the mtu, don't error
383 * out, we'll try to muddle along.
385 if (ic_dev_mtu
!= 0) {
386 strcpy(ir
.ifr_name
, ic_dev
->name
);
387 ir
.ifr_mtu
= ic_dev_mtu
;
388 if ((err
= ic_dev_ioctl(SIOCSIFMTU
, &ir
)) < 0)
389 pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
395 static int __init
ic_setup_routes(void)
397 /* No need to setup device routes, only the default route... */
399 if (ic_gateway
!= NONE
) {
403 memset(&rm
, 0, sizeof(rm
));
404 if ((ic_gateway
^ ic_myaddr
) & ic_netmask
) {
405 pr_err("IP-Config: Gateway not on directly connected network\n");
408 set_sockaddr((struct sockaddr_in
*) &rm
.rt_dst
, 0, 0);
409 set_sockaddr((struct sockaddr_in
*) &rm
.rt_genmask
, 0, 0);
410 set_sockaddr((struct sockaddr_in
*) &rm
.rt_gateway
, ic_gateway
, 0);
411 rm
.rt_flags
= RTF_UP
| RTF_GATEWAY
;
412 if ((err
= ic_route_ioctl(SIOCADDRT
, &rm
)) < 0) {
413 pr_err("IP-Config: Cannot add default route (%d)\n",
423 * Fill in default values for all missing parameters.
426 static int __init
ic_defaults(void)
429 * At this point we have no userspace running so need not
430 * claim locks on system_utsname
433 if (!ic_host_name_set
)
434 sprintf(init_utsname()->nodename
, "%pI4", &ic_myaddr
);
436 if (root_server_addr
== NONE
)
437 root_server_addr
= ic_servaddr
;
439 if (ic_netmask
== NONE
) {
440 if (IN_CLASSA(ntohl(ic_myaddr
)))
441 ic_netmask
= htonl(IN_CLASSA_NET
);
442 else if (IN_CLASSB(ntohl(ic_myaddr
)))
443 ic_netmask
= htonl(IN_CLASSB_NET
);
444 else if (IN_CLASSC(ntohl(ic_myaddr
)))
445 ic_netmask
= htonl(IN_CLASSC_NET
);
447 pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
451 printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask
);
463 static int ic_rarp_recv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*pt
, struct net_device
*orig_dev
);
465 static struct packet_type rarp_packet_type __initdata
= {
466 .type
= cpu_to_be16(ETH_P_RARP
),
467 .func
= ic_rarp_recv
,
470 static inline void __init
ic_rarp_init(void)
472 dev_add_pack(&rarp_packet_type
);
475 static inline void __init
ic_rarp_cleanup(void)
477 dev_remove_pack(&rarp_packet_type
);
481 * Process received RARP packet.
484 ic_rarp_recv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*pt
, struct net_device
*orig_dev
)
487 unsigned char *rarp_ptr
;
489 unsigned char *sha
, *tha
; /* s for "source", t for "target" */
492 if (!net_eq(dev_net(dev
), &init_net
))
495 if ((skb
= skb_share_check(skb
, GFP_ATOMIC
)) == NULL
)
498 if (!pskb_may_pull(skb
, sizeof(struct arphdr
)))
501 /* Basic sanity checks can be done without the lock. */
502 rarp
= (struct arphdr
*)skb_transport_header(skb
);
504 /* If this test doesn't pass, it's not IP, or we should
507 if (rarp
->ar_hln
!= dev
->addr_len
|| dev
->type
!= ntohs(rarp
->ar_hrd
))
510 /* If it's not a RARP reply, delete it. */
511 if (rarp
->ar_op
!= htons(ARPOP_RREPLY
))
514 /* If it's not Ethernet, delete it. */
515 if (rarp
->ar_pro
!= htons(ETH_P_IP
))
518 if (!pskb_may_pull(skb
, arp_hdr_len(dev
)))
521 /* OK, it is all there and looks valid, process... */
522 rarp
= (struct arphdr
*)skb_transport_header(skb
);
523 rarp_ptr
= (unsigned char *) (rarp
+ 1);
525 /* One reply at a time, please. */
526 spin_lock(&ic_recv_lock
);
528 /* If we already have a reply, just drop the packet */
532 /* Find the ic_device that the packet arrived on */
534 while (d
&& d
->dev
!= dev
)
537 goto drop_unlock
; /* should never happen */
539 /* Extract variable-width fields */
541 rarp_ptr
+= dev
->addr_len
;
542 memcpy(&sip
, rarp_ptr
, 4);
545 rarp_ptr
+= dev
->addr_len
;
546 memcpy(&tip
, rarp_ptr
, 4);
548 /* Discard packets which are not meant for us. */
549 if (memcmp(tha
, dev
->dev_addr
, dev
->addr_len
))
552 /* Discard packets which are not from specified server. */
553 if (ic_servaddr
!= NONE
&& ic_servaddr
!= sip
)
556 /* We have a winner! */
558 if (ic_myaddr
== NONE
)
561 ic_got_reply
= IC_RARP
;
564 /* Show's over. Nothing to see here. */
565 spin_unlock(&ic_recv_lock
);
568 /* Throw the packet out. */
575 * Send RARP request packet over a single interface.
577 static void __init
ic_rarp_send_if(struct ic_device
*d
)
579 struct net_device
*dev
= d
->dev
;
580 arp_send(ARPOP_RREQUEST
, ETH_P_RARP
, 0, dev
, 0, NULL
,
581 dev
->dev_addr
, dev
->dev_addr
);
586 * DHCP/BOOTP support.
589 #ifdef IPCONFIG_BOOTP
591 struct bootp_pkt
{ /* BOOTP packet format */
592 struct iphdr iph
; /* IP header */
593 struct udphdr udph
; /* UDP header */
594 u8 op
; /* 1=request, 2=reply */
595 u8 htype
; /* HW address type */
596 u8 hlen
; /* HW address length */
597 u8 hops
; /* Used only by gateways */
598 __be32 xid
; /* Transaction ID */
599 __be16 secs
; /* Seconds since we started */
600 __be16 flags
; /* Just what it says */
601 __be32 client_ip
; /* Client's IP address if known */
602 __be32 your_ip
; /* Assigned IP address */
603 __be32 server_ip
; /* (Next, e.g. NFS) Server's IP address */
604 __be32 relay_ip
; /* IP address of BOOTP relay */
605 u8 hw_addr
[16]; /* Client's HW address */
606 u8 serv_name
[64]; /* Server host name */
607 u8 boot_file
[128]; /* Name of boot file */
608 u8 exten
[312]; /* DHCP options / BOOTP vendor extensions */
612 #define BOOTP_REQUEST 1
613 #define BOOTP_REPLY 2
615 /* DHCP message types */
616 #define DHCPDISCOVER 1
618 #define DHCPREQUEST 3
619 #define DHCPDECLINE 4
622 #define DHCPRELEASE 7
625 static int ic_bootp_recv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*pt
, struct net_device
*orig_dev
);
627 static struct packet_type bootp_packet_type __initdata
= {
628 .type
= cpu_to_be16(ETH_P_IP
),
629 .func
= ic_bootp_recv
,
634 * Initialize DHCP/BOOTP extension fields in the request.
637 static const u8 ic_bootp_cookie
[4] = { 99, 130, 83, 99 };
642 ic_dhcp_init_options(u8
*options
)
644 u8 mt
= ((ic_servaddr
== NONE
)
645 ? DHCPDISCOVER
: DHCPREQUEST
);
649 #ifdef IPCONFIG_DEBUG
650 printk("DHCP: Sending message type %d\n", mt
);
653 memcpy(e
, ic_bootp_cookie
, 4); /* RFC1048 Magic Cookie */
656 *e
++ = 53; /* DHCP message type */
660 if (mt
== DHCPREQUEST
) {
661 *e
++ = 54; /* Server ID (IP address) */
663 memcpy(e
, &ic_servaddr
, 4);
666 *e
++ = 50; /* Requested IP address */
668 memcpy(e
, &ic_myaddr
, 4);
674 static const u8 ic_req_params
[] = {
676 3, /* Default gateway */
679 15, /* Domain name */
682 40, /* NIS domain name */
685 *e
++ = 55; /* Parameter request list */
686 *e
++ = sizeof(ic_req_params
);
687 memcpy(e
, ic_req_params
, sizeof(ic_req_params
));
688 e
+= sizeof(ic_req_params
);
690 if (ic_host_name_set
) {
691 *e
++ = 12; /* host-name */
692 len
= strlen(utsname()->nodename
);
694 memcpy(e
, utsname()->nodename
, len
);
697 if (*vendor_class_identifier
) {
698 pr_info("DHCP: sending class identifier \"%s\"\n",
699 vendor_class_identifier
);
700 *e
++ = 60; /* Class-identifier */
701 len
= strlen(vendor_class_identifier
);
703 memcpy(e
, vendor_class_identifier
, len
);
708 *e
++ = 255; /* End of the list */
711 #endif /* IPCONFIG_DHCP */
713 static void __init
ic_bootp_init_ext(u8
*e
)
715 memcpy(e
, ic_bootp_cookie
, 4); /* RFC1048 Magic Cookie */
717 *e
++ = 1; /* Subnet mask request */
720 *e
++ = 3; /* Default gateway request */
723 *e
++ = 5; /* Name server request */
726 *e
++ = 12; /* Host name request */
729 *e
++ = 40; /* NIS Domain name request */
732 *e
++ = 17; /* Boot path */
736 *e
++ = 57; /* set extension buffer size for reply */
738 *e
++ = 1; /* 128+236+8+20+14, see dhcpd sources */
741 *e
++ = 255; /* End of the list */
746 * Initialize the DHCP/BOOTP mechanism.
748 static inline void __init
ic_bootp_init(void)
752 for (i
= 0; i
< CONF_NAMESERVERS_MAX
; i
++)
753 ic_nameservers
[i
] = NONE
;
755 dev_add_pack(&bootp_packet_type
);
760 * DHCP/BOOTP cleanup.
762 static inline void __init
ic_bootp_cleanup(void)
764 dev_remove_pack(&bootp_packet_type
);
769 * Send DHCP/BOOTP request to single interface.
771 static void __init
ic_bootp_send_if(struct ic_device
*d
, unsigned long jiffies_diff
)
773 struct net_device
*dev
= d
->dev
;
777 int hlen
= LL_RESERVED_SPACE(dev
);
778 int tlen
= dev
->needed_tailroom
;
780 /* Allocate packet */
781 skb
= alloc_skb(sizeof(struct bootp_pkt
) + hlen
+ tlen
+ 15,
785 skb_reserve(skb
, hlen
);
786 b
= (struct bootp_pkt
*) skb_put(skb
, sizeof(struct bootp_pkt
));
787 memset(b
, 0, sizeof(struct bootp_pkt
));
789 /* Construct IP header */
790 skb_reset_network_header(skb
);
794 h
->tot_len
= htons(sizeof(struct bootp_pkt
));
795 h
->frag_off
= htons(IP_DF
);
797 h
->protocol
= IPPROTO_UDP
;
798 h
->daddr
= htonl(INADDR_BROADCAST
);
799 h
->check
= ip_fast_csum((unsigned char *) h
, h
->ihl
);
801 /* Construct UDP header */
802 b
->udph
.source
= htons(68);
803 b
->udph
.dest
= htons(67);
804 b
->udph
.len
= htons(sizeof(struct bootp_pkt
) - sizeof(struct iphdr
));
805 /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
807 /* Construct DHCP/BOOTP header */
808 b
->op
= BOOTP_REQUEST
;
809 if (dev
->type
< 256) /* check for false types */
810 b
->htype
= dev
->type
;
811 else if (dev
->type
== ARPHRD_IEEE802_TR
) /* fix for token ring */
812 b
->htype
= ARPHRD_IEEE802
;
813 else if (dev
->type
== ARPHRD_FDDI
)
814 b
->htype
= ARPHRD_ETHER
;
816 printk("Unknown ARP type 0x%04x for device %s\n", dev
->type
, dev
->name
);
817 b
->htype
= dev
->type
; /* can cause undefined behavior */
820 /* server_ip and your_ip address are both already zero per RFC2131 */
821 b
->hlen
= dev
->addr_len
;
822 memcpy(b
->hw_addr
, dev
->dev_addr
, dev
->addr_len
);
823 b
->secs
= htons(jiffies_diff
/ HZ
);
826 /* add DHCP options or BOOTP extensions */
828 if (ic_proto_enabled
& IC_USE_DHCP
)
829 ic_dhcp_init_options(b
->exten
);
832 ic_bootp_init_ext(b
->exten
);
834 /* Chain packet down the line... */
836 skb
->protocol
= htons(ETH_P_IP
);
837 if (dev_hard_header(skb
, dev
, ntohs(skb
->protocol
),
838 dev
->broadcast
, dev
->dev_addr
, skb
->len
) < 0) {
844 if (dev_queue_xmit(skb
) < 0)
850 * Copy BOOTP-supplied string if not already set.
852 static int __init
ic_bootp_string(char *dest
, char *src
, int len
, int max
)
858 memcpy(dest
, src
, len
);
865 * Process BOOTP extensions.
867 static void __init
ic_do_bootp_ext(u8
*ext
)
873 #ifdef IPCONFIG_DEBUG
876 printk("DHCP/BOOTP: Got extension %d:",*ext
);
877 for (c
=ext
+2; c
<ext
+2+ext
[1]; c
++)
883 case 1: /* Subnet mask */
884 if (ic_netmask
== NONE
)
885 memcpy(&ic_netmask
, ext
+1, 4);
887 case 3: /* Default gateway */
888 if (ic_gateway
== NONE
)
889 memcpy(&ic_gateway
, ext
+1, 4);
891 case 6: /* DNS server */
893 if (servers
> CONF_NAMESERVERS_MAX
)
894 servers
= CONF_NAMESERVERS_MAX
;
895 for (i
= 0; i
< servers
; i
++) {
896 if (ic_nameservers
[i
] == NONE
)
897 memcpy(&ic_nameservers
[i
], ext
+1+4*i
, 4);
900 case 12: /* Host name */
901 ic_bootp_string(utsname()->nodename
, ext
+1, *ext
,
903 ic_host_name_set
= 1;
905 case 15: /* Domain name (DNS) */
906 ic_bootp_string(ic_domain
, ext
+1, *ext
, sizeof(ic_domain
));
908 case 17: /* Root path */
909 if (!root_server_path
[0])
910 ic_bootp_string(root_server_path
, ext
+1, *ext
,
911 sizeof(root_server_path
));
913 case 26: /* Interface MTU */
914 memcpy(&mtu
, ext
+1, sizeof(mtu
));
915 ic_dev_mtu
= ntohs(mtu
);
917 case 40: /* NIS Domain name (_not_ DNS) */
918 ic_bootp_string(utsname()->domainname
, ext
+1, *ext
,
926 * Receive BOOTP reply.
928 static int __init
ic_bootp_recv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*pt
, struct net_device
*orig_dev
)
935 if (!net_eq(dev_net(dev
), &init_net
))
938 /* Perform verifications before taking the lock. */
939 if (skb
->pkt_type
== PACKET_OTHERHOST
)
942 if ((skb
= skb_share_check(skb
, GFP_ATOMIC
)) == NULL
)
945 if (!pskb_may_pull(skb
,
946 sizeof(struct iphdr
) +
947 sizeof(struct udphdr
)))
950 b
= (struct bootp_pkt
*)skb_network_header(skb
);
953 if (h
->ihl
!= 5 || h
->version
!= 4 || h
->protocol
!= IPPROTO_UDP
)
956 /* Fragments are not supported */
957 if (ip_is_fragment(h
)) {
959 pr_err("DHCP/BOOTP: Ignoring fragmented reply\n");
963 if (skb
->len
< ntohs(h
->tot_len
))
966 if (ip_fast_csum((char *) h
, h
->ihl
))
969 if (b
->udph
.source
!= htons(67) || b
->udph
.dest
!= htons(68))
972 if (ntohs(h
->tot_len
) < ntohs(b
->udph
.len
) + sizeof(struct iphdr
))
975 len
= ntohs(b
->udph
.len
) - sizeof(struct udphdr
);
976 ext_len
= len
- (sizeof(*b
) -
977 sizeof(struct iphdr
) -
978 sizeof(struct udphdr
) -
983 /* Ok the front looks good, make sure we can get at the rest. */
984 if (!pskb_may_pull(skb
, skb
->len
))
987 b
= (struct bootp_pkt
*)skb_network_header(skb
);
990 /* One reply at a time, please. */
991 spin_lock(&ic_recv_lock
);
993 /* If we already have a reply, just drop the packet */
997 /* Find the ic_device that the packet arrived on */
999 while (d
&& d
->dev
!= dev
)
1002 goto drop_unlock
; /* should never happen */
1004 /* Is it a reply to our BOOTP request? */
1005 if (b
->op
!= BOOTP_REPLY
||
1007 if (net_ratelimit())
1008 pr_err("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1013 /* Is it a reply for the device we are configuring? */
1014 if (b
->xid
!= ic_dev_xid
) {
1015 if (net_ratelimit())
1016 pr_err("DHCP/BOOTP: Ignoring delayed packet\n");
1020 /* Parse extensions */
1022 !memcmp(b
->exten
, ic_bootp_cookie
, 4)) { /* Check magic cookie */
1023 u8
*end
= (u8
*) b
+ ntohs(b
->iph
.tot_len
);
1026 #ifdef IPCONFIG_DHCP
1027 if (ic_proto_enabled
& IC_USE_DHCP
) {
1028 __be32 server_id
= NONE
;
1032 while (ext
< end
&& *ext
!= 0xff) {
1034 if (*opt
== 0) /* Padding */
1040 case 53: /* Message type */
1044 case 54: /* Server ID (IP address) */
1046 memcpy(&server_id
, opt
+ 2, 4);
1051 #ifdef IPCONFIG_DEBUG
1052 printk("DHCP: Got message type %d\n", mt
);
1057 /* While in the process of accepting one offer,
1058 * ignore all others.
1060 if (ic_myaddr
!= NONE
)
1063 /* Let's accept that offer. */
1064 ic_myaddr
= b
->your_ip
;
1065 ic_servaddr
= server_id
;
1066 #ifdef IPCONFIG_DEBUG
1067 printk("DHCP: Offered address %pI4 by server %pI4\n",
1068 &ic_myaddr
, &ic_servaddr
);
1070 /* The DHCP indicated server address takes
1071 * precedence over the bootp header one if
1072 * they are different.
1074 if ((server_id
!= NONE
) &&
1075 (b
->server_ip
!= server_id
))
1076 b
->server_ip
= ic_servaddr
;
1080 if (memcmp(dev
->dev_addr
, b
->hw_addr
, dev
->addr_len
) != 0)
1087 /* Urque. Forget it*/
1093 ic_dhcp_msgtype
= mt
;
1096 #endif /* IPCONFIG_DHCP */
1099 while (ext
< end
&& *ext
!= 0xff) {
1101 if (*opt
== 0) /* Padding */
1105 ic_do_bootp_ext(opt
);
1109 /* We have a winner! */
1111 ic_myaddr
= b
->your_ip
;
1112 ic_servaddr
= b
->server_ip
;
1113 if (ic_gateway
== NONE
&& b
->relay_ip
)
1114 ic_gateway
= b
->relay_ip
;
1115 if (ic_nameservers
[0] == NONE
)
1116 ic_nameservers
[0] = ic_servaddr
;
1117 ic_got_reply
= IC_BOOTP
;
1120 /* Show's over. Nothing to see here. */
1121 spin_unlock(&ic_recv_lock
);
1124 /* Throw the packet out. */
1135 * Dynamic IP configuration -- DHCP, BOOTP, RARP.
1138 #ifdef IPCONFIG_DYNAMIC
1140 static int __init
ic_dynamic(void)
1143 struct ic_device
*d
;
1144 unsigned long start_jiffies
, timeout
, jiff
;
1145 int do_bootp
= ic_proto_have_if
& IC_BOOTP
;
1146 int do_rarp
= ic_proto_have_if
& IC_RARP
;
1149 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1150 * This routine gets only called when some pieces of information
1151 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1153 if (!ic_proto_enabled
) {
1154 pr_err("IP-Config: Incomplete network configuration information\n");
1158 #ifdef IPCONFIG_BOOTP
1159 if ((ic_proto_enabled
^ ic_proto_have_if
) & IC_BOOTP
)
1160 pr_err("DHCP/BOOTP: No suitable device found\n");
1162 #ifdef IPCONFIG_RARP
1163 if ((ic_proto_enabled
^ ic_proto_have_if
) & IC_RARP
)
1164 pr_err("RARP: No suitable device found\n");
1167 if (!ic_proto_have_if
)
1168 /* Error message already printed */
1174 #ifdef IPCONFIG_BOOTP
1178 #ifdef IPCONFIG_RARP
1184 * Send requests and wait, until we get an answer. This loop
1185 * seems to be a terrible waste of CPU time, but actually there is
1186 * only one process running at all, so we don't need to use any
1187 * scheduler functions.
1188 * [Actually we could now, but the nothing else running note still
1191 pr_notice("Sending %s%s%s requests .",
1193 ? ((ic_proto_enabled
& IC_USE_DHCP
) ? "DHCP" : "BOOTP") : "",
1194 (do_bootp
&& do_rarp
) ? " and " : "",
1195 do_rarp
? "RARP" : "");
1197 start_jiffies
= jiffies
;
1199 retries
= CONF_SEND_RETRIES
;
1200 get_random_bytes(&timeout
, sizeof(timeout
));
1201 timeout
= CONF_BASE_TIMEOUT
+ (timeout
% (unsigned int) CONF_TIMEOUT_RANDOM
);
1203 /* Track the device we are configuring */
1204 ic_dev_xid
= d
->xid
;
1206 #ifdef IPCONFIG_BOOTP
1207 if (do_bootp
&& (d
->able
& IC_BOOTP
))
1208 ic_bootp_send_if(d
, jiffies
- start_jiffies
);
1210 #ifdef IPCONFIG_RARP
1211 if (do_rarp
&& (d
->able
& IC_RARP
))
1215 jiff
= jiffies
+ (d
->next
? CONF_INTER_TIMEOUT
: timeout
);
1216 while (time_before(jiffies
, jiff
) && !ic_got_reply
)
1217 schedule_timeout_uninterruptible(1);
1218 #ifdef IPCONFIG_DHCP
1219 /* DHCP isn't done until we get a DHCPACK. */
1220 if ((ic_got_reply
& IC_BOOTP
) &&
1221 (ic_proto_enabled
& IC_USE_DHCP
) &&
1222 ic_dhcp_msgtype
!= DHCPACK
) {
1227 #endif /* IPCONFIG_DHCP */
1238 pr_cont(" timed out!\n");
1244 timeout
= timeout CONF_TIMEOUT_MULT
;
1245 if (timeout
> CONF_TIMEOUT_MAX
)
1246 timeout
= CONF_TIMEOUT_MAX
;
1251 #ifdef IPCONFIG_BOOTP
1255 #ifdef IPCONFIG_RARP
1260 if (!ic_got_reply
) {
1265 printk("IP-Config: Got %s answer from %pI4, ",
1266 ((ic_got_reply
& IC_RARP
) ? "RARP"
1267 : (ic_proto_enabled
& IC_USE_DHCP
) ? "DHCP" : "BOOTP"),
1269 pr_cont("my address is %pI4\n", &ic_myaddr
);
1274 #endif /* IPCONFIG_DYNAMIC */
1276 #ifdef CONFIG_PROC_FS
1278 static int pnp_seq_show(struct seq_file
*seq
, void *v
)
1282 if (ic_proto_used
& IC_PROTO
)
1283 seq_printf(seq
, "#PROTO: %s\n",
1284 (ic_proto_used
& IC_RARP
) ? "RARP"
1285 : (ic_proto_used
& IC_USE_DHCP
) ? "DHCP" : "BOOTP");
1287 seq_puts(seq
, "#MANUAL\n");
1291 "domain %s\n", ic_domain
);
1292 for (i
= 0; i
< CONF_NAMESERVERS_MAX
; i
++) {
1293 if (ic_nameservers
[i
] != NONE
)
1294 seq_printf(seq
, "nameserver %pI4\n",
1295 &ic_nameservers
[i
]);
1297 if (ic_servaddr
!= NONE
)
1298 seq_printf(seq
, "bootserver %pI4\n",
1303 static int pnp_seq_open(struct inode
*indoe
, struct file
*file
)
1305 return single_open(file
, pnp_seq_show
, NULL
);
1308 static const struct file_operations pnp_seq_fops
= {
1309 .owner
= THIS_MODULE
,
1310 .open
= pnp_seq_open
,
1312 .llseek
= seq_lseek
,
1313 .release
= single_release
,
1315 #endif /* CONFIG_PROC_FS */
1318 * Extract IP address from the parameter string if needed. Note that we
1319 * need to have root_server_addr set _before_ IPConfig gets called as it
1322 __be32 __init
root_nfs_parse_addr(char *name
)
1329 while (octets
< 4) {
1330 while (*cp
>= '0' && *cp
<= '9')
1332 if (cp
== cq
|| cp
- cq
> 3)
1334 if (*cp
== '.' || octets
== 3)
1340 if (octets
== 4 && (*cp
== ':' || *cp
== '\0')) {
1343 addr
= in_aton(name
);
1344 memmove(name
, cp
, strlen(cp
) + 1);
1351 #define DEVICE_WAIT_MAX 12 /* 12 seconds */
1353 static int __init
wait_for_devices(void)
1357 for (i
= 0; i
< DEVICE_WAIT_MAX
; i
++) {
1358 struct net_device
*dev
;
1362 for_each_netdev(&init_net
, dev
) {
1363 if (ic_is_init_dev(dev
)) {
1377 * IP Autoconfig dispatcher.
1380 static int __init
ip_auto_config(void)
1383 #ifdef IPCONFIG_DYNAMIC
1384 int retries
= CONF_OPEN_RETRIES
;
1388 #ifdef CONFIG_PROC_FS
1389 proc_net_fops_create(&init_net
, "pnp", S_IRUGO
, &pnp_seq_fops
);
1390 #endif /* CONFIG_PROC_FS */
1395 DBG(("IP-Config: Entered.\n"));
1396 #ifdef IPCONFIG_DYNAMIC
1399 /* Wait for devices to appear */
1400 err
= wait_for_devices();
1404 /* Setup all network devices */
1405 err
= ic_open_devs();
1409 /* Give drivers a chance to settle */
1410 msleep(CONF_POST_OPEN
);
1413 * If the config information is insufficient (e.g., our IP address or
1414 * IP address of the boot server is missing or we have multiple network
1415 * interfaces and no default was set), use BOOTP or RARP to get the
1418 if (ic_myaddr
== NONE
||
1419 #ifdef CONFIG_ROOT_NFS
1420 (root_server_addr
== NONE
&&
1421 ic_servaddr
== NONE
&&
1422 ROOT_DEV
== Root_NFS
) ||
1424 ic_first_dev
->next
) {
1425 #ifdef IPCONFIG_DYNAMIC
1426 if (ic_dynamic() < 0) {
1430 * I don't know why, but sometimes the
1431 * eepro100 driver (at least) gets upset and
1432 * doesn't work the first time it's opened.
1433 * But then if you close it and reopen it, it
1434 * works just fine. So we need to try that at
1435 * least once before giving up.
1437 * Also, if the root will be NFS-mounted, we
1438 * have nowhere to go if DHCP fails. So we
1439 * just have to keep trying forever.
1443 #ifdef CONFIG_ROOT_NFS
1444 if (ROOT_DEV
== Root_NFS
) {
1445 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1451 pr_err("IP-Config: Reopening network devices...\n");
1455 /* Oh, well. At least we tried. */
1456 pr_err("IP-Config: Auto-configuration of network failed\n");
1459 #else /* !DYNAMIC */
1460 pr_err("IP-Config: Incomplete network configuration information\n");
1463 #endif /* IPCONFIG_DYNAMIC */
1465 /* Device selected manually or only one device -> use it */
1466 ic_dev
= ic_first_dev
->dev
;
1469 addr
= root_nfs_parse_addr(root_server_path
);
1470 if (root_server_addr
== NONE
)
1471 root_server_addr
= addr
;
1474 * Use defaults wherever applicable.
1476 if (ic_defaults() < 0)
1480 * Close all network devices except the device we've
1481 * autoconfigured and set up routes.
1484 if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1488 * Record which protocol was actually used.
1490 #ifdef IPCONFIG_DYNAMIC
1491 ic_proto_used
= ic_got_reply
| (ic_proto_enabled
& IC_USE_DHCP
);
1494 #ifndef IPCONFIG_SILENT
1496 * Clue in the operator.
1498 pr_info("IP-Config: Complete:\n");
1499 pr_info(" device=%s, addr=%pI4, mask=%pI4, gw=%pI4\n",
1500 ic_dev
->name
, &ic_myaddr
, &ic_netmask
, &ic_gateway
);
1501 pr_info(" host=%s, domain=%s, nis-domain=%s\n",
1502 utsname()->nodename
, ic_domain
, utsname()->domainname
);
1503 pr_info(" bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1504 &ic_servaddr
, &root_server_addr
, root_server_path
);
1506 pr_cont(", mtu=%d", ic_dev_mtu
);
1508 #endif /* !SILENT */
1513 late_initcall(ip_auto_config
);
1517 * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1518 * command line parameter. See Documentation/filesystems/nfs/nfsroot.txt.
1520 static int __init
ic_proto_name(char *name
)
1522 if (!strcmp(name
, "on") || !strcmp(name
, "any")) {
1525 if (!strcmp(name
, "off") || !strcmp(name
, "none")) {
1528 #ifdef CONFIG_IP_PNP_DHCP
1529 else if (!strcmp(name
, "dhcp")) {
1530 ic_proto_enabled
&= ~IC_RARP
;
1534 #ifdef CONFIG_IP_PNP_BOOTP
1535 else if (!strcmp(name
, "bootp")) {
1536 ic_proto_enabled
&= ~(IC_RARP
| IC_USE_DHCP
);
1540 #ifdef CONFIG_IP_PNP_RARP
1541 else if (!strcmp(name
, "rarp")) {
1542 ic_proto_enabled
&= ~(IC_BOOTP
| IC_USE_DHCP
);
1546 #ifdef IPCONFIG_DYNAMIC
1547 else if (!strcmp(name
, "both")) {
1548 ic_proto_enabled
&= ~IC_USE_DHCP
; /* backward compat :-( */
1555 static int __init
ip_auto_config_setup(char *addrs
)
1560 ic_set_manually
= 1;
1564 * If any dhcp, bootp etc options are set, leave autoconfig on
1565 * and skip the below static IP processing.
1567 if (ic_proto_name(addrs
))
1570 /* If no static IP is given, turn off autoconfig and bail. */
1572 strcmp(addrs
, "off") == 0 ||
1573 strcmp(addrs
, "none") == 0) {
1578 /* Parse string for static IP assignment. */
1581 if ((cp
= strchr(ip
, ':')))
1583 if (strlen(ip
) > 0) {
1584 DBG(("IP-Config: Parameter #%d: `%s'\n", num
, ip
));
1587 if ((ic_myaddr
= in_aton(ip
)) == ANY
)
1591 if ((ic_servaddr
= in_aton(ip
)) == ANY
)
1595 if ((ic_gateway
= in_aton(ip
)) == ANY
)
1599 if ((ic_netmask
= in_aton(ip
)) == ANY
)
1603 if ((dp
= strchr(ip
, '.'))) {
1605 strlcpy(utsname()->domainname
, dp
,
1606 sizeof(utsname()->domainname
));
1608 strlcpy(utsname()->nodename
, ip
,
1609 sizeof(utsname()->nodename
));
1610 ic_host_name_set
= 1;
1613 strlcpy(user_dev_name
, ip
, sizeof(user_dev_name
));
1616 if (ic_proto_name(ip
) == 0 &&
1617 ic_myaddr
== NONE
) {
1630 static int __init
nfsaddrs_config_setup(char *addrs
)
1632 return ip_auto_config_setup(addrs
);
1635 static int __init
vendor_class_identifier_setup(char *addrs
)
1637 if (strlcpy(vendor_class_identifier
, addrs
,
1638 sizeof(vendor_class_identifier
))
1639 >= sizeof(vendor_class_identifier
))
1640 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"",
1641 vendor_class_identifier
);
1645 __setup("ip=", ip_auto_config_setup
);
1646 __setup("nfsaddrs=", nfsaddrs_config_setup
);
1647 __setup("dhcpclass=", vendor_class_identifier_setup
);