diff options
Diffstat (limited to 'net/ipv4/ipconfig.c')
-rw-r--r-- | net/ipv4/ipconfig.c | 1507 |
1 files changed, 1507 insertions, 0 deletions
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c new file mode 100644 index 0000000..f250903 --- /dev/null +++ b/net/ipv4/ipconfig.c @@ -0,0 +1,1507 @@ +/* + * $Id: ipconfig.c,v 1.46 2002/02/01 22:01:04 davem Exp $ + * + * Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or + * user-supplied information to configure own IP address and routes. + * + * Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz> + * + * Derived from network configuration code in fs/nfs/nfsroot.c, + * originally Copyright (C) 1995, 1996 Gero Kuhlmann and me. + * + * BOOTP rewritten to construct and analyse packets itself instead + * of misusing the IP layer. num_bugs_causing_wrong_arp_replies--; + * -- MJ, December 1998 + * + * Fixed ip_auto_config_setup calling at startup in the new "Linker Magic" + * initialization scheme. + * - Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999 + * + * DHCP support added. To users this looks like a whole separate + * protocol, but we know it's just a bag on the side of BOOTP. + * -- Chip Salzenberg <chip@valinux.com>, May 2000 + * + * Ported DHCP support from 2.2.16 to 2.4.0-test4 + * -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000 + * + * Merged changes from 2.2.19 into 2.4.3 + * -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001 + * + * Multiple Nameservers in /proc/net/pnp + * -- Josef Siemes <jsiemes@web.de>, Aug 2002 + */ + +#include <linux/config.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/kernel.h> +#include <linux/jiffies.h> +#include <linux/random.h> +#include <linux/init.h> +#include <linux/utsname.h> +#include <linux/in.h> +#include <linux/if.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/ip.h> +#include <linux/socket.h> +#include <linux/route.h> +#include <linux/udp.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/major.h> +#include <linux/root_dev.h> +#include <linux/delay.h> +#include <net/arp.h> +#include <net/ip.h> +#include <net/ipconfig.h> + +#include <asm/uaccess.h> +#include <net/checksum.h> +#include <asm/processor.h> + +/* Define this to allow debugging output */ +#undef IPCONFIG_DEBUG + +#ifdef IPCONFIG_DEBUG +#define DBG(x) printk x +#else +#define DBG(x) do { } while(0) +#endif + +#if defined(CONFIG_IP_PNP_DHCP) +#define IPCONFIG_DHCP +#endif +#if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP) +#define IPCONFIG_BOOTP +#endif +#if defined(CONFIG_IP_PNP_RARP) +#define IPCONFIG_RARP +#endif +#if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP) +#define IPCONFIG_DYNAMIC +#endif + +/* Define the friendly delay before and after opening net devices */ +#define CONF_PRE_OPEN 500 /* Before opening: 1/2 second */ +#define CONF_POST_OPEN 1 /* After opening: 1 second */ + +/* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */ +#define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */ +#define CONF_SEND_RETRIES 6 /* Send six requests per open */ +#define CONF_INTER_TIMEOUT (HZ/2) /* Inter-device timeout: 1/2 second */ +#define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */ +#define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */ +#define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */ +#define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */ +#define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers + - '3' from resolv.h */ + + +/* + * Public IP configuration + */ + +/* This is used by platforms which might be able to set the ipconfig + * variables using firmware environment vars. If this is set, it will + * ignore such firmware variables. + */ +int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */ + +static int ic_enable __initdata = 0; /* IP config enabled? */ + +/* Protocol choice */ +int ic_proto_enabled __initdata = 0 +#ifdef IPCONFIG_BOOTP + | IC_BOOTP +#endif +#ifdef CONFIG_IP_PNP_DHCP + | IC_USE_DHCP +#endif +#ifdef IPCONFIG_RARP + | IC_RARP +#endif + ; + +static int ic_host_name_set __initdata = 0; /* Host name set by us? */ + +u32 ic_myaddr = INADDR_NONE; /* My IP address */ +static u32 ic_netmask = INADDR_NONE; /* Netmask for local subnet */ +u32 ic_gateway = INADDR_NONE; /* Gateway IP address */ + +u32 ic_servaddr = INADDR_NONE; /* Boot server IP address */ + +u32 root_server_addr = INADDR_NONE; /* Address of NFS server */ +u8 root_server_path[256] = { 0, }; /* Path to mount as root */ + +/* Persistent data: */ + +static int ic_proto_used; /* Protocol used, if any */ +static u32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */ +static u8 ic_domain[64]; /* DNS (not NIS) domain name */ + +/* + * Private state. + */ + +/* Name of user-selected boot device */ +static char user_dev_name[IFNAMSIZ] __initdata = { 0, }; + +/* Protocols supported by available interfaces */ +static int ic_proto_have_if __initdata = 0; + +#ifdef IPCONFIG_DYNAMIC +static DEFINE_SPINLOCK(ic_recv_lock); +static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */ +#endif +#ifdef IPCONFIG_DHCP +static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */ +#endif + + +/* + * Network devices + */ + +struct ic_device { + struct ic_device *next; + struct net_device *dev; + unsigned short flags; + short able; + u32 xid; +}; + +static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */ +static struct net_device *ic_dev __initdata = NULL; /* Selected device */ + +static int __init ic_open_devs(void) +{ + struct ic_device *d, **last; + struct net_device *dev; + unsigned short oflags; + + last = &ic_first_dev; + rtnl_shlock(); + + /* bring loopback device up first */ + if (dev_change_flags(&loopback_dev, loopback_dev.flags | IFF_UP) < 0) + printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev.name); + + for (dev = dev_base; dev; dev = dev->next) { + if (dev == &loopback_dev) + continue; + if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) : + (!(dev->flags & IFF_LOOPBACK) && + (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) && + strncmp(dev->name, "dummy", 5))) { + int able = 0; + if (dev->mtu >= 364) + able |= IC_BOOTP; + else + printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu); + if (!(dev->flags & IFF_NOARP)) + able |= IC_RARP; + able &= ic_proto_enabled; + if (ic_proto_enabled && !able) + continue; + oflags = dev->flags; + if (dev_change_flags(dev, oflags | IFF_UP) < 0) { + printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name); + continue; + } + if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) { + rtnl_shunlock(); + return -1; + } + d->dev = dev; + *last = d; + last = &d->next; + d->flags = oflags; + d->able = able; + if (able & IC_BOOTP) + get_random_bytes(&d->xid, sizeof(u32)); + else + d->xid = 0; + ic_proto_have_if |= able; + DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n", + dev->name, able, d->xid)); + } + } + rtnl_shunlock(); + + *last = NULL; + + if (!ic_first_dev) { + if (user_dev_name[0]) + printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name); + else + printk(KERN_ERR "IP-Config: No network devices available.\n"); + return -1; + } + return 0; +} + +static void __init ic_close_devs(void) +{ + struct ic_device *d, *next; + struct net_device *dev; + + rtnl_shlock(); + next = ic_first_dev; + while ((d = next)) { + next = d->next; + dev = d->dev; + if (dev != ic_dev) { + DBG(("IP-Config: Downing %s\n", dev->name)); + dev_change_flags(dev, d->flags); + } + kfree(d); + } + rtnl_shunlock(); +} + +/* + * Interface to various network functions. + */ + +static inline void +set_sockaddr(struct sockaddr_in *sin, u32 addr, u16 port) +{ + sin->sin_family = AF_INET; + sin->sin_addr.s_addr = addr; + sin->sin_port = port; +} + +static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg) +{ + int res; + + mm_segment_t oldfs = get_fs(); + set_fs(get_ds()); + res = devinet_ioctl(cmd, (struct ifreq __user *) arg); + set_fs(oldfs); + return res; +} + +static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg) +{ + int res; + + mm_segment_t oldfs = get_fs(); + set_fs(get_ds()); + res = ip_rt_ioctl(cmd, (void __user *) arg); + set_fs(oldfs); + return res; +} + +/* + * Set up interface addresses and routes. + */ + +static int __init ic_setup_if(void) +{ + struct ifreq ir; + struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr; + int err; + + memset(&ir, 0, sizeof(ir)); + strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name); + set_sockaddr(sin, ic_myaddr, 0); + if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) { + printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err); + return -1; + } + set_sockaddr(sin, ic_netmask, 0); + if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) { + printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err); + return -1; + } + set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0); + if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) { + printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err); + return -1; + } + return 0; +} + +static int __init ic_setup_routes(void) +{ + /* No need to setup device routes, only the default route... */ + + if (ic_gateway != INADDR_NONE) { + struct rtentry rm; + int err; + + memset(&rm, 0, sizeof(rm)); + if ((ic_gateway ^ ic_myaddr) & ic_netmask) { + printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n"); + return -1; + } + set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0); + set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0); + set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0); + rm.rt_flags = RTF_UP | RTF_GATEWAY; + if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) { + printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err); + return -1; + } + } + + return 0; +} + +/* + * Fill in default values for all missing parameters. + */ + +static int __init ic_defaults(void) +{ + /* + * At this point we have no userspace running so need not + * claim locks on system_utsname + */ + + if (!ic_host_name_set) + sprintf(system_utsname.nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr)); + + if (root_server_addr == INADDR_NONE) + root_server_addr = ic_servaddr; + + if (ic_netmask == INADDR_NONE) { + if (IN_CLASSA(ntohl(ic_myaddr))) + ic_netmask = htonl(IN_CLASSA_NET); + else if (IN_CLASSB(ntohl(ic_myaddr))) + ic_netmask = htonl(IN_CLASSB_NET); + else if (IN_CLASSC(ntohl(ic_myaddr))) + ic_netmask = htonl(IN_CLASSC_NET); + else { + printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n", + NIPQUAD(ic_myaddr)); + return -1; + } + printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask)); + } + + return 0; +} + +/* + * RARP support. + */ + +#ifdef IPCONFIG_RARP + +static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt); + +static struct packet_type rarp_packet_type __initdata = { + .type = __constant_htons(ETH_P_RARP), + .func = ic_rarp_recv, +}; + +static inline void ic_rarp_init(void) +{ + dev_add_pack(&rarp_packet_type); +} + +static inline void ic_rarp_cleanup(void) +{ + dev_remove_pack(&rarp_packet_type); +} + +/* + * Process received RARP packet. + */ +static int __init +ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt) +{ + struct arphdr *rarp; + unsigned char *rarp_ptr; + unsigned long sip, tip; + unsigned char *sha, *tha; /* s for "source", t for "target" */ + struct ic_device *d; + + if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) + return NET_RX_DROP; + + if (!pskb_may_pull(skb, sizeof(struct arphdr))) + goto drop; + + /* Basic sanity checks can be done without the lock. */ + rarp = (struct arphdr *)skb->h.raw; + + /* If this test doesn't pass, it's not IP, or we should + * ignore it anyway. + */ + if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd)) + goto drop; + + /* If it's not a RARP reply, delete it. */ + if (rarp->ar_op != htons(ARPOP_RREPLY)) + goto drop; + + /* If it's not Ethernet, delete it. */ + if (rarp->ar_pro != htons(ETH_P_IP)) + goto drop; + + if (!pskb_may_pull(skb, + sizeof(struct arphdr) + + (2 * dev->addr_len) + + (2 * 4))) + goto drop; + + /* OK, it is all there and looks valid, process... */ + rarp = (struct arphdr *)skb->h.raw; + rarp_ptr = (unsigned char *) (rarp + 1); + + /* One reply at a time, please. */ + spin_lock(&ic_recv_lock); + + /* If we already have a reply, just drop the packet */ + if (ic_got_reply) + goto drop_unlock; + + /* Find the ic_device that the packet arrived on */ + d = ic_first_dev; + while (d && d->dev != dev) + d = d->next; + if (!d) + goto drop_unlock; /* should never happen */ + + /* Extract variable-width fields */ + sha = rarp_ptr; + rarp_ptr += dev->addr_len; + memcpy(&sip, rarp_ptr, 4); + rarp_ptr += 4; + tha = rarp_ptr; + rarp_ptr += dev->addr_len; + memcpy(&tip, rarp_ptr, 4); + + /* Discard packets which are not meant for us. */ + if (memcmp(tha, dev->dev_addr, dev->addr_len)) + goto drop_unlock; + + /* Discard packets which are not from specified server. */ + if (ic_servaddr != INADDR_NONE && ic_servaddr != sip) + goto drop_unlock; + + /* We have a winner! */ + ic_dev = dev; + if (ic_myaddr == INADDR_NONE) + ic_myaddr = tip; + ic_servaddr = sip; + ic_got_reply = IC_RARP; + +drop_unlock: + /* Show's over. Nothing to see here. */ + spin_unlock(&ic_recv_lock); + +drop: + /* Throw the packet out. */ + kfree_skb(skb); + return 0; +} + + +/* + * Send RARP request packet over a single interface. + */ +static void __init ic_rarp_send_if(struct ic_device *d) +{ + struct net_device *dev = d->dev; + arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL, + dev->dev_addr, dev->dev_addr); +} +#endif + +/* + * DHCP/BOOTP support. + */ + +#ifdef IPCONFIG_BOOTP + +struct bootp_pkt { /* BOOTP packet format */ + struct iphdr iph; /* IP header */ + struct udphdr udph; /* UDP header */ + u8 op; /* 1=request, 2=reply */ + u8 htype; /* HW address type */ + u8 hlen; /* HW address length */ + u8 hops; /* Used only by gateways */ + u32 xid; /* Transaction ID */ + u16 secs; /* Seconds since we started */ + u16 flags; /* Just what it says */ + u32 client_ip; /* Client's IP address if known */ + u32 your_ip; /* Assigned IP address */ + u32 server_ip; /* (Next, e.g. NFS) Server's IP address */ + u32 relay_ip; /* IP address of BOOTP relay */ + u8 hw_addr[16]; /* Client's HW address */ + u8 serv_name[64]; /* Server host name */ + u8 boot_file[128]; /* Name of boot file */ + u8 exten[312]; /* DHCP options / BOOTP vendor extensions */ +}; + +/* packet ops */ +#define BOOTP_REQUEST 1 +#define BOOTP_REPLY 2 + +/* DHCP message types */ +#define DHCPDISCOVER 1 +#define DHCPOFFER 2 +#define DHCPREQUEST 3 +#define DHCPDECLINE 4 +#define DHCPACK 5 +#define DHCPNAK 6 +#define DHCPRELEASE 7 +#define DHCPINFORM 8 + +static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt); + +static struct packet_type bootp_packet_type __initdata = { + .type = __constant_htons(ETH_P_IP), + .func = ic_bootp_recv, +}; + + +/* + * Initialize DHCP/BOOTP extension fields in the request. + */ + +static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 }; + +#ifdef IPCONFIG_DHCP + +static void __init +ic_dhcp_init_options(u8 *options) +{ + u8 mt = ((ic_servaddr == INADDR_NONE) + ? DHCPDISCOVER : DHCPREQUEST); + u8 *e = options; + +#ifdef IPCONFIG_DEBUG + printk("DHCP: Sending message type %d\n", mt); +#endif + + memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */ + e += 4; + + *e++ = 53; /* DHCP message type */ + *e++ = 1; + *e++ = mt; + + if (mt == DHCPREQUEST) { + *e++ = 54; /* Server ID (IP address) */ + *e++ = 4; + memcpy(e, &ic_servaddr, 4); + e += 4; + + *e++ = 50; /* Requested IP address */ + *e++ = 4; + memcpy(e, &ic_myaddr, 4); + e += 4; + } + + /* always? */ + { + static const u8 ic_req_params[] = { + 1, /* Subnet mask */ + 3, /* Default gateway */ + 6, /* DNS server */ + 12, /* Host name */ + 15, /* Domain name */ + 17, /* Boot path */ + 40, /* NIS domain name */ + }; + + *e++ = 55; /* Parameter request list */ + *e++ = sizeof(ic_req_params); + memcpy(e, ic_req_params, sizeof(ic_req_params)); + e += sizeof(ic_req_params); + } + + *e++ = 255; /* End of the list */ +} + +#endif /* IPCONFIG_DHCP */ + +static void __init ic_bootp_init_ext(u8 *e) +{ + memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */ + e += 4; + *e++ = 1; /* Subnet mask request */ + *e++ = 4; + e += 4; + *e++ = 3; /* Default gateway request */ + *e++ = 4; + e += 4; + *e++ = 5; /* Name server request */ + *e++ = 8; + e += 8; + *e++ = 12; /* Host name request */ + *e++ = 32; + e += 32; + *e++ = 40; /* NIS Domain name request */ + *e++ = 32; + e += 32; + *e++ = 17; /* Boot path */ + *e++ = 40; + e += 40; + + *e++ = 57; /* set extension buffer size for reply */ + *e++ = 2; + *e++ = 1; /* 128+236+8+20+14, see dhcpd sources */ + *e++ = 150; + + *e++ = 255; /* End of the list */ +} + + +/* + * Initialize the DHCP/BOOTP mechanism. + */ +static inline void ic_bootp_init(void) +{ + int i; + + for (i = 0; i < CONF_NAMESERVERS_MAX; i++) + ic_nameservers[i] = INADDR_NONE; + + dev_add_pack(&bootp_packet_type); +} + + +/* + * DHCP/BOOTP cleanup. + */ +static inline void ic_bootp_cleanup(void) +{ + dev_remove_pack(&bootp_packet_type); +} + + +/* + * Send DHCP/BOOTP request to single interface. + */ +static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff) +{ + struct net_device *dev = d->dev; + struct sk_buff *skb; + struct bootp_pkt *b; + int hh_len = LL_RESERVED_SPACE(dev); + struct iphdr *h; + + /* Allocate packet */ + skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL); + if (!skb) + return; + skb_reserve(skb, hh_len); + b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt)); + memset(b, 0, sizeof(struct bootp_pkt)); + + /* Construct IP header */ + skb->nh.iph = h = &b->iph; + h->version = 4; + h->ihl = 5; + h->tot_len = htons(sizeof(struct bootp_pkt)); + h->frag_off = htons(IP_DF); + h->ttl = 64; + h->protocol = IPPROTO_UDP; + h->daddr = INADDR_BROADCAST; + h->check = ip_fast_csum((unsigned char *) h, h->ihl); + + /* Construct UDP header */ + b->udph.source = htons(68); + b->udph.dest = htons(67); + b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr)); + /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */ + + /* Construct DHCP/BOOTP header */ + b->op = BOOTP_REQUEST; + if (dev->type < 256) /* check for false types */ + b->htype = dev->type; + else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */ + b->htype = ARPHRD_IEEE802; + else if (dev->type == ARPHRD_FDDI) + b->htype = ARPHRD_ETHER; + else { + printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name); + b->htype = dev->type; /* can cause undefined behavior */ + } + b->hlen = dev->addr_len; + b->your_ip = INADDR_NONE; + b->server_ip = INADDR_NONE; + memcpy(b->hw_addr, dev->dev_addr, dev->addr_len); + b->secs = htons(jiffies_diff / HZ); + b->xid = d->xid; + + /* add DHCP options or BOOTP extensions */ +#ifdef IPCONFIG_DHCP + if (ic_proto_enabled & IC_USE_DHCP) + ic_dhcp_init_options(b->exten); + else +#endif + ic_bootp_init_ext(b->exten); + + /* Chain packet down the line... */ + skb->dev = dev; + skb->protocol = htons(ETH_P_IP); + if ((dev->hard_header && + dev->hard_header(skb, dev, ntohs(skb->protocol), dev->broadcast, dev->dev_addr, skb->len) < 0) || + dev_queue_xmit(skb) < 0) + printk("E"); +} + + +/* + * Copy BOOTP-supplied string if not already set. + */ +static int __init ic_bootp_string(char *dest, char *src, int len, int max) +{ + if (!len) + return 0; + if (len > max-1) + len = max-1; + memcpy(dest, src, len); + dest[len] = '\0'; + return 1; +} + + +/* + * Process BOOTP extensions. + */ +static void __init ic_do_bootp_ext(u8 *ext) +{ + u8 servers; + int i; + +#ifdef IPCONFIG_DEBUG + u8 *c; + + printk("DHCP/BOOTP: Got extension %d:",*ext); + for(c=ext+2; c<ext+2+ext[1]; c++) + printk(" %02x", *c); + printk("\n"); +#endif + + switch (*ext++) { + case 1: /* Subnet mask */ + if (ic_netmask == INADDR_NONE) + memcpy(&ic_netmask, ext+1, 4); + break; + case 3: /* Default gateway */ + if (ic_gateway == INADDR_NONE) + memcpy(&ic_gateway, ext+1, 4); + break; + case 6: /* DNS server */ + servers= *ext/4; + if (servers > CONF_NAMESERVERS_MAX) + servers = CONF_NAMESERVERS_MAX; + for (i = 0; i < servers; i++) { + if (ic_nameservers[i] == INADDR_NONE) + memcpy(&ic_nameservers[i], ext+1+4*i, 4); + } + break; + case 12: /* Host name */ + ic_bootp_string(system_utsname.nodename, ext+1, *ext, __NEW_UTS_LEN); + ic_host_name_set = 1; + break; + case 15: /* Domain name (DNS) */ + ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain)); + break; + case 17: /* Root path */ + if (!root_server_path[0]) + ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path)); + break; + case 40: /* NIS Domain name (_not_ DNS) */ + ic_bootp_string(system_utsname.domainname, ext+1, *ext, __NEW_UTS_LEN); + break; + } +} + + +/* + * Receive BOOTP reply. + */ +static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt) +{ + struct bootp_pkt *b; + struct iphdr *h; + struct ic_device *d; + int len, ext_len; + + /* Perform verifications before taking the lock. */ + if (skb->pkt_type == PACKET_OTHERHOST) + goto drop; + + if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) + return NET_RX_DROP; + + if (!pskb_may_pull(skb, + sizeof(struct iphdr) + + sizeof(struct udphdr))) + goto drop; + + b = (struct bootp_pkt *) skb->nh.iph; + h = &b->iph; + + if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP) + goto drop; + + /* Fragments are not supported */ + if (h->frag_off & htons(IP_OFFSET | IP_MF)) { + if (net_ratelimit()) + printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented " + "reply.\n"); + goto drop; + } + + if (skb->len < ntohs(h->tot_len)) + goto drop; + + if (ip_fast_csum((char *) h, h->ihl)) + goto drop; + + if (b->udph.source != htons(67) || b->udph.dest != htons(68)) + goto drop; + + if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr)) + goto drop; + + len = ntohs(b->udph.len) - sizeof(struct udphdr); + ext_len = len - (sizeof(*b) - + sizeof(struct iphdr) - + sizeof(struct udphdr) - + sizeof(b->exten)); + if (ext_len < 0) + goto drop; + + /* Ok the front looks good, make sure we can get at the rest. */ + if (!pskb_may_pull(skb, skb->len)) + goto drop; + + b = (struct bootp_pkt *) skb->nh.iph; + h = &b->iph; + + /* One reply at a time, please. */ + spin_lock(&ic_recv_lock); + + /* If we already have a reply, just drop the packet */ + if (ic_got_reply) + goto drop_unlock; + + /* Find the ic_device that the packet arrived on */ + d = ic_first_dev; + while (d && d->dev != dev) + d = d->next; + if (!d) + goto drop_unlock; /* should never happen */ + + /* Is it a reply to our BOOTP request? */ + if (b->op != BOOTP_REPLY || + b->xid != d->xid) { + if (net_ratelimit()) + printk(KERN_ERR "DHCP/BOOTP: Reply not for us, " + "op[%x] xid[%x]\n", + b->op, b->xid); + goto drop_unlock; + } + + /* Parse extensions */ + if (ext_len >= 4 && + !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */ + u8 *end = (u8 *) b + ntohs(b->iph.tot_len); + u8 *ext; + +#ifdef IPCONFIG_DHCP + if (ic_proto_enabled & IC_USE_DHCP) { + u32 server_id = INADDR_NONE; + int mt = 0; + + ext = &b->exten[4]; + while (ext < end && *ext != 0xff) { + u8 *opt = ext++; + if (*opt == 0) /* Padding */ + continue; + ext += *ext + 1; + if (ext >= end) + break; + switch (*opt) { + case 53: /* Message type */ + if (opt[1]) + mt = opt[2]; + break; + case 54: /* Server ID (IP address) */ + if (opt[1] >= 4) + memcpy(&server_id, opt + 2, 4); + break; + }; + } + +#ifdef IPCONFIG_DEBUG + printk("DHCP: Got message type %d\n", mt); +#endif + + switch (mt) { + case DHCPOFFER: + /* While in the process of accepting one offer, + * ignore all others. + */ + if (ic_myaddr != INADDR_NONE) + goto drop_unlock; + + /* Let's accept that offer. */ + ic_myaddr = b->your_ip; + ic_servaddr = server_id; +#ifdef IPCONFIG_DEBUG + printk("DHCP: Offered address %u.%u.%u.%u", + NIPQUAD(ic_myaddr)); + printk(" by server %u.%u.%u.%u\n", + NIPQUAD(ic_servaddr)); +#endif + /* The DHCP indicated server address takes + * precedence over the bootp header one if + * they are different. + */ + if ((server_id != INADDR_NONE) && + (b->server_ip != server_id)) + b->server_ip = ic_servaddr; + break; + + case DHCPACK: + if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0) + goto drop_unlock; + + /* Yeah! */ + break; + + default: + /* Urque. Forget it*/ + ic_myaddr = INADDR_NONE; + ic_servaddr = INADDR_NONE; + goto drop_unlock; + }; + + ic_dhcp_msgtype = mt; + + } +#endif /* IPCONFIG_DHCP */ + + ext = &b->exten[4]; + while (ext < end && *ext != 0xff) { + u8 *opt = ext++; + if (*opt == 0) /* Padding */ + continue; + ext += *ext + 1; + if (ext < end) + ic_do_bootp_ext(opt); + } + } + + /* We have a winner! */ + ic_dev = dev; + ic_myaddr = b->your_ip; + ic_servaddr = b->server_ip; + if (ic_gateway == INADDR_NONE && b->relay_ip) + ic_gateway = b->relay_ip; + if (ic_nameservers[0] == INADDR_NONE) + ic_nameservers[0] = ic_servaddr; + ic_got_reply = IC_BOOTP; + +drop_unlock: + /* Show's over. Nothing to see here. */ + spin_unlock(&ic_recv_lock); + +drop: + /* Throw the packet out. */ + kfree_skb(skb); + + return 0; +} + + +#endif + + +/* + * Dynamic IP configuration -- DHCP, BOOTP, RARP. + */ + +#ifdef IPCONFIG_DYNAMIC + +static int __init ic_dynamic(void) +{ + int retries; + struct ic_device *d; + unsigned long start_jiffies, timeout, jiff; + int do_bootp = ic_proto_have_if & IC_BOOTP; + int do_rarp = ic_proto_have_if & IC_RARP; + + /* + * If none of DHCP/BOOTP/RARP was selected, return with an error. + * This routine gets only called when some pieces of information + * are missing, and without DHCP/BOOTP/RARP we are unable to get it. + */ + if (!ic_proto_enabled) { + printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n"); + return -1; + } + +#ifdef IPCONFIG_BOOTP + if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP) + printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n"); +#endif +#ifdef IPCONFIG_RARP + if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP) + printk(KERN_ERR "RARP: No suitable device found.\n"); +#endif + + if (!ic_proto_have_if) + /* Error message already printed */ + return -1; + + /* + * Setup protocols + */ +#ifdef IPCONFIG_BOOTP + if (do_bootp) + ic_bootp_init(); +#endif +#ifdef IPCONFIG_RARP + if (do_rarp) + ic_rarp_init(); +#endif + + /* + * Send requests and wait, until we get an answer. This loop + * seems to be a terrible waste of CPU time, but actually there is + * only one process running at all, so we don't need to use any + * scheduler functions. + * [Actually we could now, but the nothing else running note still + * applies.. - AC] + */ + printk(KERN_NOTICE "Sending %s%s%s requests .", + do_bootp + ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "", + (do_bootp && do_rarp) ? " and " : "", + do_rarp ? "RARP" : ""); + + start_jiffies = jiffies; + d = ic_first_dev; + retries = CONF_SEND_RETRIES; + get_random_bytes(&timeout, sizeof(timeout)); + timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM); + for(;;) { +#ifdef IPCONFIG_BOOTP + if (do_bootp && (d->able & IC_BOOTP)) + ic_bootp_send_if(d, jiffies - start_jiffies); +#endif +#ifdef IPCONFIG_RARP + if (do_rarp && (d->able & IC_RARP)) + ic_rarp_send_if(d); +#endif + + jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout); + while (time_before(jiffies, jiff) && !ic_got_reply) { + set_current_state(TASK_UNINTERRUPTIBLE); + schedule_timeout(1); + } +#ifdef IPCONFIG_DHCP + /* DHCP isn't done until we get a DHCPACK. */ + if ((ic_got_reply & IC_BOOTP) + && (ic_proto_enabled & IC_USE_DHCP) + && ic_dhcp_msgtype != DHCPACK) + { + ic_got_reply = 0; + printk(","); + continue; + } +#endif /* IPCONFIG_DHCP */ + + if (ic_got_reply) { + printk(" OK\n"); + break; + } + + if ((d = d->next)) + continue; + + if (! --retries) { + printk(" timed out!\n"); + break; + } + + d = ic_first_dev; + + timeout = timeout CONF_TIMEOUT_MULT; + if (timeout > CONF_TIMEOUT_MAX) + timeout = CONF_TIMEOUT_MAX; + + printk("."); + } + +#ifdef IPCONFIG_BOOTP + if (do_bootp) + ic_bootp_cleanup(); +#endif +#ifdef IPCONFIG_RARP + if (do_rarp) + ic_rarp_cleanup(); +#endif + + if (!ic_got_reply) + return -1; + + printk("IP-Config: Got %s answer from %u.%u.%u.%u, ", + ((ic_got_reply & IC_RARP) ? "RARP" + : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"), + NIPQUAD(ic_servaddr)); + printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr)); + + return 0; +} + +#endif /* IPCONFIG_DYNAMIC */ + +#ifdef CONFIG_PROC_FS + +static int pnp_seq_show(struct seq_file *seq, void *v) +{ + int i; + + if (ic_proto_used & IC_PROTO) + seq_printf(seq, "#PROTO: %s\n", + (ic_proto_used & IC_RARP) ? "RARP" + : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP"); + else + seq_puts(seq, "#MANUAL\n"); + + if (ic_domain[0]) + seq_printf(seq, + "domain %s\n", ic_domain); + for (i = 0; i < CONF_NAMESERVERS_MAX; i++) { + if (ic_nameservers[i] != INADDR_NONE) + seq_printf(seq, + "nameserver %u.%u.%u.%u\n", + NIPQUAD(ic_nameservers[i])); + } + if (ic_servaddr != INADDR_NONE) + seq_printf(seq, + "bootserver %u.%u.%u.%u\n", + NIPQUAD(ic_servaddr)); + return 0; +} + +static int pnp_seq_open(struct inode *indoe, struct file *file) +{ + return single_open(file, pnp_seq_show, NULL); +} + +static struct file_operations pnp_seq_fops = { + .owner = THIS_MODULE, + .open = pnp_seq_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; +#endif /* CONFIG_PROC_FS */ + +/* + * Extract IP address from the parameter string if needed. Note that we + * need to have root_server_addr set _before_ IPConfig gets called as it + * can override it. + */ +u32 __init root_nfs_parse_addr(char *name) +{ + u32 addr; + int octets = 0; + char *cp, *cq; + + cp = cq = name; + while (octets < 4) { + while (*cp >= '0' && *cp <= '9') + cp++; + if (cp == cq || cp - cq > 3) + break; + if (*cp == '.' || octets == 3) + octets++; + if (octets < 4) + cp++; + cq = cp; + } + if (octets == 4 && (*cp == ':' || *cp == '\0')) { + if (*cp == ':') + *cp++ = '\0'; + addr = in_aton(name); + memmove(name, cp, strlen(cp) + 1); + } else + addr = INADDR_NONE; + + return addr; +} + +/* + * IP Autoconfig dispatcher. + */ + +static int __init ip_auto_config(void) +{ + u32 addr; + +#ifdef CONFIG_PROC_FS + proc_net_fops_create("pnp", S_IRUGO, &pnp_seq_fops); +#endif /* CONFIG_PROC_FS */ + + if (!ic_enable) + return 0; + + DBG(("IP-Config: Entered.\n")); +#ifdef IPCONFIG_DYNAMIC + try_try_again: +#endif + /* Give hardware a chance to settle */ + msleep(CONF_PRE_OPEN); + + /* Setup all network devices */ + if (ic_open_devs() < 0) + return -1; + + /* Give drivers a chance to settle */ + ssleep(CONF_POST_OPEN); + + /* + * If the config information is insufficient (e.g., our IP address or + * IP address of the boot server is missing or we have multiple network + * interfaces and no default was set), use BOOTP or RARP to get the + * missing values. + */ + if (ic_myaddr == INADDR_NONE || +#ifdef CONFIG_ROOT_NFS + (MAJOR(ROOT_DEV) == UNNAMED_MAJOR + && root_server_addr == INADDR_NONE + && ic_servaddr == INADDR_NONE) || +#endif + ic_first_dev->next) { +#ifdef IPCONFIG_DYNAMIC + + int retries = CONF_OPEN_RETRIES; + + if (ic_dynamic() < 0) { + ic_close_devs(); + + /* + * I don't know why, but sometimes the + * eepro100 driver (at least) gets upset and + * doesn't work the first time it's opened. + * But then if you close it and reopen it, it + * works just fine. So we need to try that at + * least once before giving up. + * + * Also, if the root will be NFS-mounted, we + * have nowhere to go if DHCP fails. So we + * just have to keep trying forever. + * + * -- Chip + */ +#ifdef CONFIG_ROOT_NFS + if (ROOT_DEV == Root_NFS) { + printk(KERN_ERR + "IP-Config: Retrying forever (NFS root)...\n"); + goto try_try_again; + } +#endif + + if (--retries) { + printk(KERN_ERR + "IP-Config: Reopening network devices...\n"); + goto try_try_again; + } + + /* Oh, well. At least we tried. */ + printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n"); + return -1; + } +#else /* !DYNAMIC */ + printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n"); + ic_close_devs(); + return -1; +#endif /* IPCONFIG_DYNAMIC */ + } else { + /* Device selected manually or only one device -> use it */ + ic_dev = ic_first_dev->dev; + } + + addr = root_nfs_parse_addr(root_server_path); + if (root_server_addr == INADDR_NONE) + root_server_addr = addr; + + /* + * Use defaults whereever applicable. + */ + if (ic_defaults() < 0) + return -1; + + /* + * Close all network devices except the device we've + * autoconfigured and set up routes. + */ + ic_close_devs(); + if (ic_setup_if() < 0 || ic_setup_routes() < 0) + return -1; + + /* + * Record which protocol was actually used. + */ +#ifdef IPCONFIG_DYNAMIC + ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP); +#endif + +#ifndef IPCONFIG_SILENT + /* + * Clue in the operator. + */ + printk("IP-Config: Complete:"); + printk("\n device=%s", ic_dev->name); + printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr)); + printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask)); + printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway)); + printk(",\n host=%s, domain=%s, nis-domain=%s", + system_utsname.nodename, ic_domain, system_utsname.domainname); + printk(",\n bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr)); + printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr)); + printk(", rootpath=%s", root_server_path); + printk("\n"); +#endif /* !SILENT */ + + return 0; +} + +late_initcall(ip_auto_config); + + +/* + * Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel + * command line parameter. It consists of option fields separated by colons in + * the following order: + * + * <client-ip>:<server-ip>:<gw-ip>:<netmask>:<host name>:<device>:<PROTO> + * + * Any of the fields can be empty which means to use a default value: + * <client-ip> - address given by BOOTP or RARP + * <server-ip> - address of host returning BOOTP or RARP packet + * <gw-ip> - none, or the address returned by BOOTP + * <netmask> - automatically determined from <client-ip>, or the + * one returned by BOOTP + * <host name> - <client-ip> in ASCII notation, or the name returned + * by BOOTP + * <device> - use all available devices + * <PROTO>: + * off|none - don't do autoconfig at all (DEFAULT) + * on|any - use any configured protocol + * dhcp|bootp|rarp - use only the specified protocol + * both - use both BOOTP and RARP (not DHCP) + */ +static int __init ic_proto_name(char *name) +{ + if (!strcmp(name, "on") || !strcmp(name, "any")) { + return 1; + } +#ifdef CONFIG_IP_PNP_DHCP + else if (!strcmp(name, "dhcp")) { + ic_proto_enabled &= ~IC_RARP; + return 1; + } +#endif +#ifdef CONFIG_IP_PNP_BOOTP + else if (!strcmp(name, "bootp")) { + ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP); + return 1; + } +#endif +#ifdef CONFIG_IP_PNP_RARP + else if (!strcmp(name, "rarp")) { + ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP); + return 1; + } +#endif +#ifdef IPCONFIG_DYNAMIC + else if (!strcmp(name, "both")) { + ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */ + return 1; + } +#endif + return 0; +} + +static int __init ip_auto_config_setup(char *addrs) +{ + char *cp, *ip, *dp; + int num = 0; + + ic_set_manually = 1; + + ic_enable = (*addrs && + (strcmp(addrs, "off") != 0) && + (strcmp(addrs, "none") != 0)); + if (!ic_enable) + return 1; + + if (ic_proto_name(addrs)) + return 1; + + /* Parse the whole string */ + ip = addrs; + while (ip && *ip) { + if ((cp = strchr(ip, ':'))) + *cp++ = '\0'; + if (strlen(ip) > 0) { + DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip)); + switch (num) { + case 0: + if ((ic_myaddr = in_aton(ip)) == INADDR_ANY) + ic_myaddr = INADDR_NONE; + break; + case 1: + if ((ic_servaddr = in_aton(ip)) == INADDR_ANY) + ic_servaddr = INADDR_NONE; + break; + case 2: + if ((ic_gateway = in_aton(ip)) == INADDR_ANY) + ic_gateway = INADDR_NONE; + break; + case 3: + if ((ic_netmask = in_aton(ip)) == INADDR_ANY) + ic_netmask = INADDR_NONE; + break; + case 4: + if ((dp = strchr(ip, '.'))) { + *dp++ = '\0'; + strlcpy(system_utsname.domainname, dp, + sizeof(system_utsname.domainname)); + } + strlcpy(system_utsname.nodename, ip, + sizeof(system_utsname.nodename)); + ic_host_name_set = 1; + break; + case 5: + strlcpy(user_dev_name, ip, sizeof(user_dev_name)); + break; + case 6: + ic_proto_name(ip); + break; + } + } + ip = cp; + num++; + } + + return 1; +} + +static int __init nfsaddrs_config_setup(char *addrs) +{ + return ip_auto_config_setup(addrs); +} + +__setup("ip=", ip_auto_config_setup); +__setup("nfsaddrs=", nfsaddrs_config_setup); |