/* * $Id: ipconfig.c,v 1.20 1999/03/28 10:18:28 davem Exp $ * * Automatic Configuration of IP -- use BOOTP or RARP or user-supplied * information to configure own IP address and routes. * * Copyright (C) 1996--1998 Martin Mares * * 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 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* 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 /* Define the timeout for waiting for a RARP/BOOTP reply */ #define CONF_BASE_TIMEOUT (HZ*5) /* Initial timeout: 5 seconds */ #define CONF_RETRIES 10 /* 10 retries */ #define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */ #define CONF_TIMEOUT_MULT *5/4 /* Rate of timeout growth */ #define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */ /* IP configuration */ static char user_dev_name[IFNAMSIZ] __initdata = { 0, };/* Name of user-selected boot device */ u32 ic_myaddr __initdata = INADDR_NONE; /* My IP address */ u32 ic_servaddr __initdata = INADDR_NONE; /* Server IP address */ u32 ic_gateway __initdata = INADDR_NONE; /* Gateway IP address */ u32 ic_netmask __initdata = INADDR_NONE; /* Netmask for local subnet */ int ic_enable __initdata = 1; /* Automatic IP configuration enabled */ int ic_host_name_set __initdata = 0; /* Host name configured manually */ int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */ u32 root_server_addr __initdata = INADDR_NONE; /* Address of boot server */ u8 root_server_path[256] __initdata = { 0, }; /* Path to mount as root */ #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_RARP) #define CONFIG_IP_PNP_DYNAMIC static int ic_proto_enabled __initdata = 0 /* Protocols enabled */ #ifdef CONFIG_IP_PNP_BOOTP | IC_BOOTP #endif #ifdef CONFIG_IP_PNP_RARP | IC_RARP #endif ; static int ic_got_reply __initdata = 0; /* Protocol(s) we got reply from */ #else static int ic_proto_enabled __initdata = 0; #endif static int ic_proto_have_if __initdata = 0; /* * Network devices */ struct ic_device { struct ic_device *next; struct device *dev; unsigned short flags; int able; }; static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */ static struct device *ic_dev __initdata = NULL; /* Selected device */ static int __init ic_open_devs(void) { struct ic_device *d, **last; struct device *dev; unsigned short oflags; last = &ic_first_dev; for (dev = dev_base; dev; dev = dev->next) 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 "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))) return -1; d->dev = dev; *last = d; last = &d->next; d->flags = oflags; d->able = able; ic_proto_have_if |= able; DBG(("IP-Config: Opened %s (able=%d)\n", dev->name, able)); } *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 device *dev; 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_s(d, sizeof(struct ic_device)); } } /* * 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, 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, 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) strcpy(system_utsname.nodename, in_ntoa(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 %08x\n", ic_myaddr); return -1; } printk("IP-Config: Guessing netmask %s\n", in_ntoa(ic_netmask)); } return 0; } /* * RARP support. */ #ifdef CONFIG_IP_PNP_RARP static int ic_rarp_recv(struct sk_buff *skb, struct device *dev, struct packet_type *pt); static struct packet_type rarp_packet_type __initdata = { __constant_htons(ETH_P_RARP), NULL, /* Listen to all devices */ ic_rarp_recv, NULL, NULL }; 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 device *dev, struct packet_type *pt) { struct arphdr *rarp = (struct arphdr *)skb->h.raw; unsigned char *rarp_ptr = (unsigned char *) (rarp + 1); unsigned long sip, tip; unsigned char *sha, *tha; /* s for "source", t for "target" */ /* If we already have a reply, just drop the packet */ if (ic_got_reply) goto drop; /* 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; /* 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; /* Discard packets which are not from specified server. */ if (ic_servaddr != INADDR_NONE && ic_servaddr != sip) goto drop; /* Victory! The packet is what we were looking for! */ if (!ic_got_reply) { ic_got_reply = IC_RARP; ic_dev = dev; if (ic_myaddr == INADDR_NONE) ic_myaddr = tip; ic_servaddr = sip; } /* And throw the packet out... */ drop: kfree_skb(skb); return 0; } /* * Send RARP request packet over all devices which allow RARP. */ static void __init ic_rarp_send(void) { struct ic_device *d; for (d=ic_first_dev; d; d=d->next) if (d->able & IC_RARP) { struct device *dev = d->dev; arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL, dev->dev_addr, dev->dev_addr); } } #endif /* * BOOTP support. */ #ifdef CONFIG_IP_PNP_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; /* 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 vendor_area[128]; /* Area for extensions */ }; #define BOOTP_REQUEST 1 #define BOOTP_REPLY 2 static u32 ic_bootp_xid; static int ic_bootp_recv(struct sk_buff *skb, struct device *dev, struct packet_type *pt); static struct packet_type bootp_packet_type __initdata = { __constant_htons(ETH_P_IP), NULL, /* Listen to all devices */ ic_bootp_recv, NULL, NULL }; /* * Initialize BOOTP extension fields in the request. */ static void __init ic_bootp_init_ext(u8 *e) { *e++ = 99; /* RFC1048 Magic Cookie */ *e++ = 130; *e++ = 83; *e++ = 99; *e++ = 1; /* Subnet mask request */ *e++ = 4; e += 4; *e++ = 3; /* Default gateway request */ *e++ = 4; e += 4; *e++ = 12; /* Host name request */ *e++ = 32; e += 32; *e++ = 40; /* NIS Domain name request */ *e++ = 32; e += 32; *e++ = 17; /* Boot path */ *e++ = 32; e += 32; *e = 255; /* End of the list */ } /* * Initialize the BOOTP mechanism. */ static inline void ic_bootp_init(void) { get_random_bytes(&ic_bootp_xid, sizeof(u32)); DBG(("BOOTP: XID=%08x\n", ic_bootp_xid)); dev_add_pack(&bootp_packet_type); } /* * BOOTP cleanup. */ static inline void ic_bootp_cleanup(void) { dev_remove_pack(&bootp_packet_type); } /* * Send BOOTP request to single interface. */ static void __init ic_bootp_send_if(struct ic_device *d, u32 jiffies) { struct device *dev = d->dev; struct sk_buff *skb; struct bootp_pkt *b; int hh_len = (dev->hard_header_len + 15) & ~15; 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 BOOTP header */ b->op = BOOTP_REQUEST; b->htype = dev->type; b->hlen = dev->addr_len; memcpy(b->hw_addr, dev->dev_addr, dev->addr_len); b->secs = htons(jiffies / HZ); b->xid = ic_bootp_xid; ic_bootp_init_ext(b->vendor_area); /* Chain packet down the line... */ skb->dev = dev; skb->protocol = __constant_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"); } /* * Send BOOTP requests to all interfaces. */ static void __init ic_bootp_send(u32 jiffies) { struct ic_device *d; for(d=ic_first_dev; d; d=d->next) if (d->able & IC_BOOTP) ic_bootp_send_if(d, jiffies); } /* * 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; strncpy(dest, src, len); dest[len] = '\0'; return 1; } /* * Process BOOTP extension. */ static void __init ic_do_bootp_ext(u8 *ext) { #ifdef IPCONFIG_DEBUG u8 *c; printk("BOOTP: Got extension %02x",*ext); for(c=ext+2; cnh.iph; struct iphdr *h = &b->iph; int len; /* If we already have a reply, just drop the packet */ if (ic_got_reply) goto drop; /* Check whether it's a BOOTP packet */ if (skb->pkt_type == PACKET_OTHERHOST || skb->len < sizeof(struct udphdr) + sizeof(struct iphdr) || h->ihl != 5 || h->version != 4 || ip_fast_csum((char *) h, h->ihl) != 0 || skb->len < ntohs(h->tot_len) || h->protocol != IPPROTO_UDP || b->udph.source != htons(67) || b->udph.dest != htons(68) || ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr)) goto drop; /* Fragments are not supported */ if (h->frag_off & htons(IP_OFFSET|IP_MF)) { printk(KERN_ERR "BOOTP: Ignoring fragmented reply.\n"); goto drop; } /* Is it a reply to our BOOTP request? */ len = ntohs(b->udph.len) - sizeof(struct udphdr); if (len < 300 || /* See RFC 951:2.1 */ b->op != BOOTP_REPLY || b->xid != ic_bootp_xid) { printk("?"); goto drop; } /* Extract basic fields */ ic_myaddr = b->your_ip; ic_servaddr = b->server_ip; ic_got_reply = IC_BOOTP; ic_dev = dev; /* Parse extensions */ if (b->vendor_area[0] == 99 && /* Check magic cookie */ b->vendor_area[1] == 130 && b->vendor_area[2] == 83 && b->vendor_area[3] == 99) { u8 *ext = &b->vendor_area[4]; u8 *end = (u8 *) b + len; while (ext < end && *ext != 0xff) { if (*ext == 0) /* Padding */ ext++; else { u8 *opt = ext; ext += ext[1] + 2; if (ext <= end) ic_do_bootp_ext(opt); } } } if (ic_gateway == INADDR_NONE && b->relay_ip) ic_gateway = b->relay_ip; drop: kfree_skb(skb); return 0; } #endif /* * Dynamic IP configuration -- BOOTP and RARP. */ #ifdef CONFIG_IP_PNP_DYNAMIC static int __init ic_dynamic(void) { int retries; unsigned long timeout, jiff; unsigned long start_jiffies; int do_rarp = ic_proto_have_if & IC_RARP; int do_bootp = ic_proto_have_if & IC_BOOTP; /* * If neither BOOTP nor RARP was selected, return with an error. This * routine gets only called when some pieces of information are mis- * sing, and without BOOTP and RARP we are not able to get that in- * formation. */ if (!ic_proto_enabled) { printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n"); return -1; } #ifdef CONFIG_IP_PNP_BOOTP if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP) printk(KERN_ERR "BOOTP: No suitable device found.\n"); #endif #ifdef CONFIG_IP_PNP_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 RARP and BOOTP protocols */ #ifdef CONFIG_IP_PNP_RARP if (do_rarp) ic_rarp_init(); #endif #ifdef CONFIG_IP_PNP_BOOTP if (do_bootp) ic_bootp_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 ? "BOOTP" : "", do_bootp && do_rarp ? " and " : "", do_rarp ? "RARP" : ""); start_jiffies = jiffies; retries = CONF_RETRIES; get_random_bytes(&timeout, sizeof(timeout)); timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM); for(;;) { #ifdef CONFIG_IP_PNP_BOOTP if (do_bootp) ic_bootp_send(jiffies - start_jiffies); #endif #ifdef CONFIG_IP_PNP_RARP if (do_rarp) ic_rarp_send(); #endif printk("."); jiff = jiffies + timeout; while (jiffies < jiff && !ic_got_reply) ; if (ic_got_reply) { printk(" OK\n"); break; } if (! --retries) { printk(" timed out!\n"); break; } timeout = timeout CONF_TIMEOUT_MULT; if (timeout > CONF_TIMEOUT_MAX) timeout = CONF_TIMEOUT_MAX; } #ifdef CONFIG_IP_PNP_RARP if (do_rarp) ic_rarp_cleanup(); #endif #ifdef CONFIG_IP_PNP_BOOTP if (do_bootp) ic_bootp_cleanup(); #endif if (!ic_got_reply) return -1; printk("IP-Config: Got %s answer from %s, ", (ic_got_reply & IC_BOOTP) ? "BOOTP" : "RARP", in_ntoa(ic_servaddr)); printk("my address is %s\n", in_ntoa(ic_myaddr)); return 0; } #endif /* * IP Autoconfig dispatcher. */ int __init ip_auto_config(void) { if (!ic_enable) return 0; DBG(("IP-Config: Entered.\n")); /* Setup all network devices */ if (ic_open_devs() < 0) return -1; /* * 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 (root_server_addr == INADDR_NONE && ic_servaddr == INADDR_NONE) || #endif ic_first_dev->next) { #ifdef CONFIG_IP_PNP_DYNAMIC if (ic_dynamic() < 0) { printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n"); ic_close_devs(); return -1; } #else printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n"); ic_close_devs(); return -1; #endif } else { ic_dev = ic_first_dev->dev; /* Device selected manually or only one device -> use it */ } /* * 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; DBG(("IP-Config: device=%s, local=%08x, server=%08x, boot=%08x, gw=%08x, mask=%08x\n", ic_dev->name, ic_myaddr, ic_servaddr, root_server_addr, ic_gateway, ic_netmask)); DBG(("IP-Config: host=%s, domain=%s, path=`%s'\n", system_utsname.nodename, system_utsname.domainname, root_server_path)); return 0; } /* * 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: * * :::::: * * Any of the fields can be empty which means to use a default value: * - address given by BOOTP or RARP * - address of host returning BOOTP or RARP packet * - none, or the address returned by BOOTP * - automatically determined from , or the * one returned by BOOTP * - in ASCII notation, or the name returned * by BOOTP * - use all available devices * - use both protocols to determine my own address */ static int __init ic_proto_name(char *name) { if (!strcmp(name, "off")) { ic_proto_enabled = 0; return 1; } #ifdef CONFIG_IP_PNP_BOOTP else if (!strcmp(name, "bootp")) { ic_proto_enabled &= ~IC_RARP; return 1; } #endif #ifdef CONFIG_IP_PNP_RARP else if (!strcmp(name, "rarp")) { ic_proto_enabled &= ~IC_BOOTP; return 1; } #endif #ifdef CONFIG_IP_PNP_DYNAMIC else if (!strcmp(name, "both")) { return 1; } #endif return 0; } void __init ip_auto_config_setup(char *addrs, int *ints) { char *cp, *ip, *dp; int num = 0; ic_set_manually = 1; if (!strcmp(addrs, "off")) { ic_enable = 0; return; } if (ic_proto_name(addrs)) return; /* 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'; strncpy(system_utsname.domainname, dp, __NEW_UTS_LEN); system_utsname.domainname[__NEW_UTS_LEN] = '\0'; } strncpy(system_utsname.nodename, ip, __NEW_UTS_LEN); system_utsname.nodename[__NEW_UTS_LEN] = '\0'; ic_host_name_set = 1; break; case 5: strncpy(user_dev_name, ip, IFNAMSIZ); user_dev_name[IFNAMSIZ-1] = '\0'; break; case 6: ic_proto_name(ip); break; } } ip = cp; num++; } }