/* * NET3 IP device support routines. * * Version: $Id: devinet.c,v 1.44 2001/10/31 21:55:54 davem Exp $ * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Derived from the IP parts of dev.c 1.0.19 * Authors: Ross Biro * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * Mark Evans, <evansmp@uhura.aston.ac.uk> * * Additional Authors: * Alan Cox, <gw4pts@gw4pts.ampr.org> * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> * * Changes: * Alexey Kuznetsov: pa_* fields are replaced with ifaddr * lists. * Cyrus Durgin: updated for kmod * Matthias Andree: in devinet_ioctl, compare label and * address (4.4BSD alias style support), * fall back to comparing just the label * if no match found. */ #include <linux/config.h> #include <asm/uaccess.h> #include <asm/system.h> #include <linux/bitops.h> #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/in.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/if_ether.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/skbuff.h> #include <linux/rtnetlink.h> #include <linux/init.h> #include <linux/notifier.h> #include <linux/inetdevice.h> #include <linux/igmp.h> #ifdef CONFIG_SYSCTL #include <linux/sysctl.h> #endif #include <linux/kmod.h> #include <net/ip.h> #include <net/route.h> #include <net/ip_fib.h> struct ipv4_devconf ipv4_devconf = { .accept_redirects = 1, .send_redirects = 1, .secure_redirects = 1, .shared_media = 1, }; static struct ipv4_devconf ipv4_devconf_dflt = { .accept_redirects = 1, .send_redirects = 1, .secure_redirects = 1, .shared_media = 1, .accept_source_route = 1, }; static void rtmsg_ifa(int event, struct in_ifaddr *); static struct notifier_block *inetaddr_chain; static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, int destroy); #ifdef CONFIG_SYSCTL static void devinet_sysctl_register(struct in_device *in_dev, struct ipv4_devconf *p); static void devinet_sysctl_unregister(struct ipv4_devconf *p); #endif /* Locks all the inet devices. */ static struct in_ifaddr *inet_alloc_ifa(void) { struct in_ifaddr *ifa = kmalloc(sizeof(*ifa), GFP_KERNEL); if (ifa) { memset(ifa, 0, sizeof(*ifa)); INIT_RCU_HEAD(&ifa->rcu_head); } return ifa; } static void inet_rcu_free_ifa(struct rcu_head *head) { struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head); if (ifa->ifa_dev) in_dev_put(ifa->ifa_dev); kfree(ifa); } static inline void inet_free_ifa(struct in_ifaddr *ifa) { call_rcu(&ifa->rcu_head, inet_rcu_free_ifa); } void in_dev_finish_destroy(struct in_device *idev) { struct net_device *dev = idev->dev; BUG_TRAP(!idev->ifa_list); BUG_TRAP(!idev->mc_list); #ifdef NET_REFCNT_DEBUG printk(KERN_DEBUG "in_dev_finish_destroy: %p=%s\n", idev, dev ? dev->name : "NIL"); #endif dev_put(dev); if (!idev->dead) printk("Freeing alive in_device %p\n", idev); else { kfree(idev); } } struct in_device *inetdev_init(struct net_device *dev) { struct in_device *in_dev; ASSERT_RTNL(); in_dev = kmalloc(sizeof(*in_dev), GFP_KERNEL); if (!in_dev) goto out; memset(in_dev, 0, sizeof(*in_dev)); INIT_RCU_HEAD(&in_dev->rcu_head); memcpy(&in_dev->cnf, &ipv4_devconf_dflt, sizeof(in_dev->cnf)); in_dev->cnf.sysctl = NULL; in_dev->dev = dev; if ((in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl)) == NULL) goto out_kfree; /* Reference in_dev->dev */ dev_hold(dev); #ifdef CONFIG_SYSCTL neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4, NET_IPV4_NEIGH, "ipv4", NULL, NULL); #endif /* Account for reference dev->ip_ptr */ in_dev_hold(in_dev); rcu_assign_pointer(dev->ip_ptr, in_dev); #ifdef CONFIG_SYSCTL devinet_sysctl_register(in_dev, &in_dev->cnf); #endif ip_mc_init_dev(in_dev); if (dev->flags & IFF_UP) ip_mc_up(in_dev); out: return in_dev; out_kfree: kfree(in_dev); in_dev = NULL; goto out; } static void in_dev_rcu_put(struct rcu_head *head) { struct in_device *idev = container_of(head, struct in_device, rcu_head); in_dev_put(idev); } static void inetdev_destroy(struct in_device *in_dev) { struct in_ifaddr *ifa; struct net_device *dev; ASSERT_RTNL(); dev = in_dev->dev; if (dev == &loopback_dev) return; in_dev->dead = 1; ip_mc_destroy_dev(in_dev); while ((ifa = in_dev->ifa_list) != NULL) { inet_del_ifa(in_dev, &in_dev->ifa_list, 0); inet_free_ifa(ifa); } #ifdef CONFIG_SYSCTL devinet_sysctl_unregister(&in_dev->cnf); #endif dev->ip_ptr = NULL; #ifdef CONFIG_SYSCTL neigh_sysctl_unregister(in_dev->arp_parms); #endif neigh_parms_release(&arp_tbl, in_dev->arp_parms); arp_ifdown(dev); call_rcu(&in_dev->rcu_head, in_dev_rcu_put); } int inet_addr_onlink(struct in_device *in_dev, u32 a, u32 b) { rcu_read_lock(); for_primary_ifa(in_dev) { if (inet_ifa_match(a, ifa)) { if (!b || inet_ifa_match(b, ifa)) { rcu_read_unlock(); return 1; } } } endfor_ifa(in_dev); rcu_read_unlock(); return 0; } static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, int destroy) { struct in_ifaddr *promote = NULL; struct in_ifaddr *ifa1 = *ifap; ASSERT_RTNL(); /* 1. Deleting primary ifaddr forces deletion all secondaries * unless alias promotion is set **/ if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) { struct in_ifaddr *ifa; struct in_ifaddr **ifap1 = &ifa1->ifa_next; while ((ifa = *ifap1) != NULL) { if (!(ifa->ifa_flags & IFA_F_SECONDARY) || ifa1->ifa_mask != ifa->ifa_mask || !inet_ifa_match(ifa1->ifa_address, ifa)) { ifap1 = &ifa->ifa_next; continue; } if (!IN_DEV_PROMOTE_SECONDARIES(in_dev)) { *ifap1 = ifa->ifa_next; rtmsg_ifa(RTM_DELADDR, ifa); notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa); inet_free_ifa(ifa); } else { promote = ifa; break; } } } /* 2. Unlink it */ *ifap = ifa1->ifa_next; /* 3. Announce address deletion */ /* Send message first, then call notifier. At first sight, FIB update triggered by notifier will refer to already deleted ifaddr, that could confuse netlink listeners. It is not true: look, gated sees that route deleted and if it still thinks that ifaddr is valid, it will try to restore deleted routes... Grr. So that, this order is correct. */ rtmsg_ifa(RTM_DELADDR, ifa1); notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1); if (destroy) { inet_free_ifa(ifa1); if (!in_dev->ifa_list) inetdev_destroy(in_dev); } if (promote && IN_DEV_PROMOTE_SECONDARIES(in_dev)) { /* not sure if we should send a delete notify first? */ promote->ifa_flags &= ~IFA_F_SECONDARY; rtmsg_ifa(RTM_NEWADDR, promote); notifier_call_chain(&inetaddr_chain, NETDEV_UP, promote); } } static int inet_insert_ifa(struct in_ifaddr *ifa) { struct in_device *in_dev = ifa->ifa_dev; struct in_ifaddr *ifa1, **ifap, **last_primary; ASSERT_RTNL(); if (!ifa->ifa_local) { inet_free_ifa(ifa); return 0; } ifa->ifa_flags &= ~IFA_F_SECONDARY; last_primary = &in_dev->ifa_list; for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL; ifap = &ifa1->ifa_next) { if (!(ifa1->ifa_flags & IFA_F_SECONDARY) && ifa->ifa_scope <= ifa1->ifa_scope) last_primary = &ifa1->ifa_next; if (ifa1->ifa_mask == ifa->ifa_mask && inet_ifa_match(ifa1->ifa_address, ifa)) { if (ifa1->ifa_local == ifa->ifa_local) { inet_free_ifa(ifa); return -EEXIST; } if (ifa1->ifa_scope != ifa->ifa_scope) { inet_free_ifa(ifa); return -EINVAL; } ifa->ifa_flags |= IFA_F_SECONDARY; } } if (!(ifa->ifa_flags & IFA_F_SECONDARY)) { net_srandom(ifa->ifa_local); ifap = last_primary; } ifa->ifa_next = *ifap; *ifap = ifa; /* Send message first, then call notifier. Notifier will trigger FIB update, so that listeners of netlink will know about new ifaddr */ rtmsg_ifa(RTM_NEWADDR, ifa); notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa); return 0; } static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa) { struct in_device *in_dev = __in_dev_get(dev); ASSERT_RTNL(); if (!in_dev) { in_dev = inetdev_init(dev); if (!in_dev) { inet_free_ifa(ifa); return -ENOBUFS; } } if (ifa->ifa_dev != in_dev) { BUG_TRAP(!ifa->ifa_dev); in_dev_hold(in_dev); ifa->ifa_dev = in_dev; } if (LOOPBACK(ifa->ifa_local)) ifa->ifa_scope = RT_SCOPE_HOST; return inet_insert_ifa(ifa); } struct in_device *inetdev_by_index(int ifindex) { struct net_device *dev; struct in_device *in_dev = NULL; read_lock(&dev_base_lock); dev = __dev_get_by_index(ifindex); if (dev) in_dev = in_dev_get(dev); read_unlock(&dev_base_lock); return in_dev; } /* Called only from RTNL semaphored context. No locks. */ struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, u32 prefix, u32 mask) { ASSERT_RTNL(); for_primary_ifa(in_dev) { if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa)) return ifa; } endfor_ifa(in_dev); return NULL; } static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) { struct rtattr **rta = arg; struct in_device *in_dev; struct ifaddrmsg *ifm = NLMSG_DATA(nlh); struct in_ifaddr *ifa, **ifap; ASSERT_RTNL(); if ((in_dev = inetdev_by_index(ifm->ifa_index)) == NULL) goto out; __in_dev_put(in_dev); for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; ifap = &ifa->ifa_next) { if ((rta[IFA_LOCAL - 1] && memcmp(RTA_DATA(rta[IFA_LOCAL - 1]), &ifa->ifa_local, 4)) || (rta[IFA_LABEL - 1] && rtattr_strcmp(rta[IFA_LABEL - 1], ifa->ifa_label)) || (rta[IFA_ADDRESS - 1] && (ifm->ifa_prefixlen != ifa->ifa_prefixlen || !inet_ifa_match(*(u32*)RTA_DATA(rta[IFA_ADDRESS - 1]), ifa)))) continue; inet_del_ifa(in_dev, ifap, 1); return 0; } out: return -EADDRNOTAVAIL; } static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) { struct rtattr **rta = arg; struct net_device *dev; struct in_device *in_dev; struct ifaddrmsg *ifm = NLMSG_DATA(nlh); struct in_ifaddr *ifa; int rc = -EINVAL; ASSERT_RTNL(); if (ifm->ifa_prefixlen > 32 || !rta[IFA_LOCAL - 1]) goto out; rc = -ENODEV; if ((dev = __dev_get_by_index(ifm->ifa_index)) == NULL) goto out; rc = -ENOBUFS; if ((in_dev = __in_dev_get(dev)) == NULL) { in_dev = inetdev_init(dev); if (!in_dev) goto out; } if ((ifa = inet_alloc_ifa()) == NULL) goto out; if (!rta[IFA_ADDRESS - 1]) rta[IFA_ADDRESS - 1] = rta[IFA_LOCAL - 1]; memcpy(&ifa->ifa_local, RTA_DATA(rta[IFA_LOCAL - 1]), 4); memcpy(&ifa->ifa_address, RTA_DATA(rta[IFA_ADDRESS - 1]), 4); ifa->ifa_prefixlen = ifm->ifa_prefixlen; ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen); if (rta[IFA_BROADCAST - 1]) memcpy(&ifa->ifa_broadcast, RTA_DATA(rta[IFA_BROADCAST - 1]), 4); if (rta[IFA_ANYCAST - 1]) memcpy(&ifa->ifa_anycast, RTA_DATA(rta[IFA_ANYCAST - 1]), 4); ifa->ifa_flags = ifm->ifa_flags; ifa->ifa_scope = ifm->ifa_scope; in_dev_hold(in_dev); ifa->ifa_dev = in_dev; if (rta[IFA_LABEL - 1]) rtattr_strlcpy(ifa->ifa_label, rta[IFA_LABEL - 1], IFNAMSIZ); else memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); rc = inet_insert_ifa(ifa); out: return rc; } /* * Determine a default network mask, based on the IP address. */ static __inline__ int inet_abc_len(u32 addr) { int rc = -1; /* Something else, probably a multicast. */ if (ZERONET(addr)) rc = 0; else { addr = ntohl(addr); if (IN_CLASSA(addr)) rc = 8; else if (IN_CLASSB(addr)) rc = 16; else if (IN_CLASSC(addr)) rc = 24; } return rc; } int devinet_ioctl(unsigned int cmd, void __user *arg) { struct ifreq ifr; struct sockaddr_in sin_orig; struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr; struct in_device *in_dev; struct in_ifaddr **ifap = NULL; struct in_ifaddr *ifa = NULL; struct net_device *dev; char *colon; int ret = -EFAULT; int tryaddrmatch = 0; /* * Fetch the caller's info block into kernel space */ if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) goto out; ifr.ifr_name[IFNAMSIZ - 1] = 0; /* save original address for comparison */ memcpy(&sin_orig, sin, sizeof(*sin)); colon = strchr(ifr.ifr_name, ':'); if (colon) *colon = 0; #ifdef CONFIG_KMOD dev_load(ifr.ifr_name); #endif switch(cmd) { case SIOCGIFADDR: /* Get interface address */ case SIOCGIFBRDADDR: /* Get the broadcast address */ case SIOCGIFDSTADDR: /* Get the destination address */ case SIOCGIFNETMASK: /* Get the netmask for the interface */ /* Note that these ioctls will not sleep, so that we do not impose a lock. One day we will be forced to put shlock here (I mean SMP) */ tryaddrmatch = (sin_orig.sin_family == AF_INET); memset(sin, 0, sizeof(*sin)); sin->sin_family = AF_INET; break; case SIOCSIFFLAGS: ret = -EACCES; if (!capable(CAP_NET_ADMIN)) goto out; break; case SIOCSIFADDR: /* Set interface address (and family) */ case SIOCSIFBRDADDR: /* Set the broadcast address */ case SIOCSIFDSTADDR: /* Set the destination address */ case SIOCSIFNETMASK: /* Set the netmask for the interface */ ret = -EACCES; if (!capable(CAP_NET_ADMIN)) goto out; ret = -EINVAL; if (sin->sin_family != AF_INET) goto out; break; default: ret = -EINVAL; goto out; } rtnl_lock(); ret = -ENODEV; if ((dev = __dev_get_by_name(ifr.ifr_name)) == NULL) goto done; if (colon) *colon = ':'; if ((in_dev = __in_dev_get(dev)) != NULL) { if (tryaddrmatch) { /* Matthias Andree */ /* compare label and address (4.4BSD style) */ /* note: we only do this for a limited set of ioctls and only if the original address family was AF_INET. This is checked above. */ for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; ifap = &ifa->ifa_next) { if (!strcmp(ifr.ifr_name, ifa->ifa_label) && sin_orig.sin_addr.s_addr == ifa->ifa_address) { break; /* found */ } } } /* we didn't get a match, maybe the application is 4.3BSD-style and passed in junk so we fall back to comparing just the label */ if (!ifa) { for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; ifap = &ifa->ifa_next) if (!strcmp(ifr.ifr_name, ifa->ifa_label)) break; } } ret = -EADDRNOTAVAIL; if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS) goto done; switch(cmd) { case SIOCGIFADDR: /* Get interface address */ sin->sin_addr.s_addr = ifa->ifa_local; goto rarok; case SIOCGIFBRDADDR: /* Get the broadcast address */ sin->sin_addr.s_addr = ifa->ifa_broadcast; goto rarok; case SIOCGIFDSTADDR: /* Get the destination address */ sin->sin_addr.s_addr = ifa->ifa_address; goto rarok; case SIOCGIFNETMASK: /* Get the netmask for the interface */ sin->sin_addr.s_addr = ifa->ifa_mask; goto rarok; case SIOCSIFFLAGS: if (colon) { ret = -EADDRNOTAVAIL; if (!ifa) break; ret = 0; if (!(ifr.ifr_flags & IFF_UP)) inet_del_ifa(in_dev, ifap, 1); break; } ret = dev_change_flags(dev, ifr.ifr_flags); break; case SIOCSIFADDR: /* Set interface address (and family) */ ret = -EINVAL; if (inet_abc_len(sin->sin_addr.s_addr) < 0) break; if (!ifa) { ret = -ENOBUFS; if ((ifa = inet_alloc_ifa()) == NULL) break; if (colon) memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ); else memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); } else { ret = 0; if (ifa->ifa_local == sin->sin_addr.s_addr) break; inet_del_ifa(in_dev, ifap, 0); ifa->ifa_broadcast = 0; ifa->ifa_anycast = 0; } ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr; if (!(dev->flags & IFF_POINTOPOINT)) { ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address); ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen); if ((dev->flags & IFF_BROADCAST) && ifa->ifa_prefixlen < 31) ifa->ifa_broadcast = ifa->ifa_address | ~ifa->ifa_mask; } else { ifa->ifa_prefixlen = 32; ifa->ifa_mask = inet_make_mask(32); } ret = inet_set_ifa(dev, ifa); break; case SIOCSIFBRDADDR: /* Set the broadcast address */ ret = 0; if (ifa->ifa_broadcast != sin->sin_addr.s_addr) { inet_del_ifa(in_dev, ifap, 0); ifa->ifa_broadcast = sin->sin_addr.s_addr; inet_insert_ifa(ifa); } break; case SIOCSIFDSTADDR: /* Set the destination address */ ret = 0; if (ifa->ifa_address == sin->sin_addr.s_addr) break; ret = -EINVAL; if (inet_abc_len(sin->sin_addr.s_addr) < 0) break; ret = 0; inet_del_ifa(in_dev, ifap, 0); ifa->ifa_address = sin->sin_addr.s_addr; inet_insert_ifa(ifa); break; case SIOCSIFNETMASK: /* Set the netmask for the interface */ /* * The mask we set must be legal. */ ret = -EINVAL; if (bad_mask(sin->sin_addr.s_addr, 0)) break; ret = 0; if (ifa->ifa_mask != sin->sin_addr.s_addr) { inet_del_ifa(in_dev, ifap, 0); ifa->ifa_mask = sin->sin_addr.s_addr; ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask); /* See if current broadcast address matches * with current netmask, then recalculate * the broadcast address. Otherwise it's a * funny address, so don't touch it since * the user seems to know what (s)he's doing... */ if ((dev->flags & IFF_BROADCAST) && (ifa->ifa_prefixlen < 31) && (ifa->ifa_broadcast == (ifa->ifa_local|~ifa->ifa_mask))) { ifa->ifa_broadcast = (ifa->ifa_local | ~sin->sin_addr.s_addr); } inet_insert_ifa(ifa); } break; } done: rtnl_unlock(); out: return ret; rarok: rtnl_unlock(); ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0; goto out; } static int inet_gifconf(struct net_device *dev, char __user *buf, int len) { struct in_device *in_dev = __in_dev_get(dev); struct in_ifaddr *ifa; struct ifreq ifr; int done = 0; if (!in_dev || (ifa = in_dev->ifa_list) == NULL) goto out; for (; ifa; ifa = ifa->ifa_next) { if (!buf) { done += sizeof(ifr); continue; } if (len < (int) sizeof(ifr)) break; memset(&ifr, 0, sizeof(struct ifreq)); if (ifa->ifa_label) strcpy(ifr.ifr_name, ifa->ifa_label); else strcpy(ifr.ifr_name, dev->name); (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET; (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr = ifa->ifa_local; if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) { done = -EFAULT; break; } buf += sizeof(struct ifreq); len -= sizeof(struct ifreq); done += sizeof(struct ifreq); } out: return done; } u32 inet_select_addr(const struct net_device *dev, u32 dst, int scope) { u32 addr = 0; struct in_device *in_dev; rcu_read_lock(); in_dev = __in_dev_get(dev); if (!in_dev) goto no_in_dev; for_primary_ifa(in_dev) { if (ifa->ifa_scope > scope) continue; if (!dst || inet_ifa_match(dst, ifa)) { addr = ifa->ifa_local; break; } if (!addr) addr = ifa->ifa_local; } endfor_ifa(in_dev); no_in_dev: rcu_read_unlock(); if (addr) goto out; /* Not loopback addresses on loopback should be preferred in this case. It is importnat that lo is the first interface in dev_base list. */ read_lock(&dev_base_lock); rcu_read_lock(); for (dev = dev_base; dev; dev = dev->next) { if ((in_dev = __in_dev_get(dev)) == NULL) continue; for_primary_ifa(in_dev) { if (ifa->ifa_scope != RT_SCOPE_LINK && ifa->ifa_scope <= scope) { addr = ifa->ifa_local; goto out_unlock_both; } } endfor_ifa(in_dev); } out_unlock_both: read_unlock(&dev_base_lock); rcu_read_unlock(); out: return addr; } static u32 confirm_addr_indev(struct in_device *in_dev, u32 dst, u32 local, int scope) { int same = 0; u32 addr = 0; for_ifa(in_dev) { if (!addr && (local == ifa->ifa_local || !local) && ifa->ifa_scope <= scope) { addr = ifa->ifa_local; if (same) break; } if (!same) { same = (!local || inet_ifa_match(local, ifa)) && (!dst || inet_ifa_match(dst, ifa)); if (same && addr) { if (local || !dst) break; /* Is the selected addr into dst subnet? */ if (inet_ifa_match(addr, ifa)) break; /* No, then can we use new local src? */ if (ifa->ifa_scope <= scope) { addr = ifa->ifa_local; break; } /* search for large dst subnet for addr */ same = 0; } } } endfor_ifa(in_dev); return same? addr : 0; } /* * Confirm that local IP address exists using wildcards: * - dev: only on this interface, 0=any interface * - dst: only in the same subnet as dst, 0=any dst * - local: address, 0=autoselect the local address * - scope: maximum allowed scope value for the local address */ u32 inet_confirm_addr(const struct net_device *dev, u32 dst, u32 local, int scope) { u32 addr = 0; struct in_device *in_dev; if (dev) { rcu_read_lock(); if ((in_dev = __in_dev_get(dev))) addr = confirm_addr_indev(in_dev, dst, local, scope); rcu_read_unlock(); return addr; } read_lock(&dev_base_lock); rcu_read_lock(); for (dev = dev_base; dev; dev = dev->next) { if ((in_dev = __in_dev_get(dev))) { addr = confirm_addr_indev(in_dev, dst, local, scope); if (addr) break; } } rcu_read_unlock(); read_unlock(&dev_base_lock); return addr; } /* * Device notifier */ int register_inetaddr_notifier(struct notifier_block *nb) { return notifier_chain_register(&inetaddr_chain, nb); } int unregister_inetaddr_notifier(struct notifier_block *nb) { return notifier_chain_unregister(&inetaddr_chain, nb); } /* Rename ifa_labels for a device name change. Make some effort to preserve existing * alias numbering and to create unique labels if possible. */ static void inetdev_changename(struct net_device *dev, struct in_device *in_dev) { struct in_ifaddr *ifa; int named = 0; for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { char old[IFNAMSIZ], *dot; memcpy(old, ifa->ifa_label, IFNAMSIZ); memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); if (named++ == 0) continue; dot = strchr(ifa->ifa_label, ':'); if (dot == NULL) { sprintf(old, ":%d", named); dot = old; } if (strlen(dot) + strlen(dev->name) < IFNAMSIZ) { strcat(ifa->ifa_label, dot); } else { strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot); } } } /* Called only under RTNL semaphore */ static int inetdev_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = ptr; struct in_device *in_dev = __in_dev_get(dev); ASSERT_RTNL(); if (!in_dev) { if (event == NETDEV_REGISTER && dev == &loopback_dev) { in_dev = inetdev_init(dev); if (!in_dev) panic("devinet: Failed to create loopback\n"); in_dev->cnf.no_xfrm = 1; in_dev->cnf.no_policy = 1; } goto out; } switch (event) { case NETDEV_REGISTER: printk(KERN_DEBUG "inetdev_event: bug\n"); dev->ip_ptr = NULL; break; case NETDEV_UP: if (dev->mtu < 68) break; if (dev == &loopback_dev) { struct in_ifaddr *ifa; if ((ifa = inet_alloc_ifa()) != NULL) { ifa->ifa_local = ifa->ifa_address = htonl(INADDR_LOOPBACK); ifa->ifa_prefixlen = 8; ifa->ifa_mask = inet_make_mask(8); in_dev_hold(in_dev); ifa->ifa_dev = in_dev; ifa->ifa_scope = RT_SCOPE_HOST; memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); inet_insert_ifa(ifa); } } ip_mc_up(in_dev); break; case NETDEV_DOWN: ip_mc_down(in_dev); break; case NETDEV_CHANGEMTU: if (dev->mtu >= 68) break; /* MTU falled under 68, disable IP */ case NETDEV_UNREGISTER: inetdev_destroy(in_dev); break; case NETDEV_CHANGENAME: /* Do not notify about label change, this event is * not interesting to applications using netlink. */ inetdev_changename(dev, in_dev); #ifdef CONFIG_SYSCTL devinet_sysctl_unregister(&in_dev->cnf); neigh_sysctl_unregister(in_dev->arp_parms); neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4, NET_IPV4_NEIGH, "ipv4", NULL, NULL); devinet_sysctl_register(in_dev, &in_dev->cnf); #endif break; } out: return NOTIFY_DONE; } static struct notifier_block ip_netdev_notifier = { .notifier_call =inetdev_event, }; static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa, u32 pid, u32 seq, int event, unsigned int flags) { struct ifaddrmsg *ifm; struct nlmsghdr *nlh; unsigned char *b = skb->tail; nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*ifm), flags); ifm = NLMSG_DATA(nlh); ifm->ifa_family = AF_INET; ifm->ifa_prefixlen = ifa->ifa_prefixlen; ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT; ifm->ifa_scope = ifa->ifa_scope; ifm->ifa_index = ifa->ifa_dev->dev->ifindex; if (ifa->ifa_address) RTA_PUT(skb, IFA_ADDRESS, 4, &ifa->ifa_address); if (ifa->ifa_local) RTA_PUT(skb, IFA_LOCAL, 4, &ifa->ifa_local); if (ifa->ifa_broadcast) RTA_PUT(skb, IFA_BROADCAST, 4, &ifa->ifa_broadcast); if (ifa->ifa_anycast) RTA_PUT(skb, IFA_ANYCAST, 4, &ifa->ifa_anycast); if (ifa->ifa_label[0]) RTA_PUT(skb, IFA_LABEL, IFNAMSIZ, &ifa->ifa_label); nlh->nlmsg_len = skb->tail - b; return skb->len; nlmsg_failure: rtattr_failure: skb_trim(skb, b - skb->data); return -1; } static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb) { int idx, ip_idx; struct net_device *dev; struct in_device *in_dev; struct in_ifaddr *ifa; int s_ip_idx, s_idx = cb->args[0]; s_ip_idx = ip_idx = cb->args[1]; read_lock(&dev_base_lock); for (dev = dev_base, idx = 0; dev; dev = dev->next, idx++) { if (idx < s_idx) continue; if (idx > s_idx) s_ip_idx = 0; rcu_read_lock(); if ((in_dev = __in_dev_get(dev)) == NULL) { rcu_read_unlock(); continue; } for (ifa = in_dev->ifa_list, ip_idx = 0; ifa; ifa = ifa->ifa_next, ip_idx++) { if (ip_idx < s_ip_idx) continue; if (inet_fill_ifaddr(skb, ifa, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, RTM_NEWADDR, NLM_F_MULTI) <= 0) { rcu_read_unlock(); goto done; } } rcu_read_unlock(); } done: read_unlock(&dev_base_lock); cb->args[0] = idx; cb->args[1] = ip_idx; return skb->len; } static void rtmsg_ifa(int event, struct in_ifaddr* ifa) { int size = NLMSG_SPACE(sizeof(struct ifaddrmsg) + 128); struct sk_buff *skb = alloc_skb(size, GFP_KERNEL); if (!skb) netlink_set_err(rtnl, 0, RTNLGRP_IPV4_IFADDR, ENOBUFS); else if (inet_fill_ifaddr(skb, ifa, current->pid, 0, event, 0) < 0) { kfree_skb(skb); netlink_set_err(rtnl, 0, RTNLGRP_IPV4_IFADDR, EINVAL); } else { netlink_broadcast(rtnl, skb, 0, RTNLGRP_IPV4_IFADDR, GFP_KERNEL); } } static struct rtnetlink_link inet_rtnetlink_table[RTM_NR_MSGTYPES] = { [RTM_NEWADDR - RTM_BASE] = { .doit = inet_rtm_newaddr, }, [RTM_DELADDR - RTM_BASE] = { .doit = inet_rtm_deladdr, }, [RTM_GETADDR - RTM_BASE] = { .dumpit = inet_dump_ifaddr, }, [RTM_NEWROUTE - RTM_BASE] = { .doit = inet_rtm_newroute, }, [RTM_DELROUTE - RTM_BASE] = { .doit = inet_rtm_delroute, }, [RTM_GETROUTE - RTM_BASE] = { .doit = inet_rtm_getroute, .dumpit = inet_dump_fib, }, #ifdef CONFIG_IP_MULTIPLE_TABLES [RTM_NEWRULE - RTM_BASE] = { .doit = inet_rtm_newrule, }, [RTM_DELRULE - RTM_BASE] = { .doit = inet_rtm_delrule, }, [RTM_GETRULE - RTM_BASE] = { .dumpit = inet_dump_rules, }, #endif }; #ifdef CONFIG_SYSCTL void inet_forward_change(void) { struct net_device *dev; int on = ipv4_devconf.forwarding; ipv4_devconf.accept_redirects = !on; ipv4_devconf_dflt.forwarding = on; read_lock(&dev_base_lock); for (dev = dev_base; dev; dev = dev->next) { struct in_device *in_dev; rcu_read_lock(); in_dev = __in_dev_get(dev); if (in_dev) in_dev->cnf.forwarding = on; rcu_read_unlock(); } read_unlock(&dev_base_lock); rt_cache_flush(0); } static int devinet_sysctl_forward(ctl_table *ctl, int write, struct file* filp, void __user *buffer, size_t *lenp, loff_t *ppos) { int *valp = ctl->data; int val = *valp; int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos); if (write && *valp != val) { if (valp == &ipv4_devconf.forwarding) inet_forward_change(); else if (valp != &ipv4_devconf_dflt.forwarding) rt_cache_flush(0); } return ret; } int ipv4_doint_and_flush(ctl_table *ctl, int write, struct file* filp, void __user *buffer, size_t *lenp, loff_t *ppos) { int *valp = ctl->data; int val = *valp; int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos); if (write && *valp != val) rt_cache_flush(0); return ret; } int ipv4_doint_and_flush_strategy(ctl_table *table, int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen, void **context) { int *valp = table->data; int new; if (!newval || !newlen) return 0; if (newlen != sizeof(int)) return -EINVAL; if (get_user(new, (int __user *)newval)) return -EFAULT; if (new == *valp) return 0; if (oldval && oldlenp) { size_t len; if (get_user(len, oldlenp)) return -EFAULT; if (len) { if (len > table->maxlen) len = table->maxlen; if (copy_to_user(oldval, valp, len)) return -EFAULT; if (put_user(len, oldlenp)) return -EFAULT; } } *valp = new; rt_cache_flush(0); return 1; } static struct devinet_sysctl_table { struct ctl_table_header *sysctl_header; ctl_table devinet_vars[__NET_IPV4_CONF_MAX]; ctl_table devinet_dev[2]; ctl_table devinet_conf_dir[2]; ctl_table devinet_proto_dir[2]; ctl_table devinet_root_dir[2]; } devinet_sysctl = { .devinet_vars = { { .ctl_name = NET_IPV4_CONF_FORWARDING, .procname = "forwarding", .data = &ipv4_devconf.forwarding, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &devinet_sysctl_forward, }, { .ctl_name = NET_IPV4_CONF_MC_FORWARDING, .procname = "mc_forwarding", .data = &ipv4_devconf.mc_forwarding, .maxlen = sizeof(int), .mode = 0444, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_ACCEPT_REDIRECTS, .procname = "accept_redirects", .data = &ipv4_devconf.accept_redirects, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_SECURE_REDIRECTS, .procname = "secure_redirects", .data = &ipv4_devconf.secure_redirects, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_SHARED_MEDIA, .procname = "shared_media", .data = &ipv4_devconf.shared_media, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_RP_FILTER, .procname = "rp_filter", .data = &ipv4_devconf.rp_filter, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_SEND_REDIRECTS, .procname = "send_redirects", .data = &ipv4_devconf.send_redirects, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_ACCEPT_SOURCE_ROUTE, .procname = "accept_source_route", .data = &ipv4_devconf.accept_source_route, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_PROXY_ARP, .procname = "proxy_arp", .data = &ipv4_devconf.proxy_arp, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_MEDIUM_ID, .procname = "medium_id", .data = &ipv4_devconf.medium_id, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_BOOTP_RELAY, .procname = "bootp_relay", .data = &ipv4_devconf.bootp_relay, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_LOG_MARTIANS, .procname = "log_martians", .data = &ipv4_devconf.log_martians, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_TAG, .procname = "tag", .data = &ipv4_devconf.tag, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_ARPFILTER, .procname = "arp_filter", .data = &ipv4_devconf.arp_filter, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_ARP_ANNOUNCE, .procname = "arp_announce", .data = &ipv4_devconf.arp_announce, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_ARP_IGNORE, .procname = "arp_ignore", .data = &ipv4_devconf.arp_ignore, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .ctl_name = NET_IPV4_CONF_NOXFRM, .procname = "disable_xfrm", .data = &ipv4_devconf.no_xfrm, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &ipv4_doint_and_flush, .strategy = &ipv4_doint_and_flush_strategy, }, { .ctl_name = NET_IPV4_CONF_NOPOLICY, .procname = "disable_policy", .data = &ipv4_devconf.no_policy, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &ipv4_doint_and_flush, .strategy = &ipv4_doint_and_flush_strategy, }, { .ctl_name = NET_IPV4_CONF_FORCE_IGMP_VERSION, .procname = "force_igmp_version", .data = &ipv4_devconf.force_igmp_version, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &ipv4_doint_and_flush, .strategy = &ipv4_doint_and_flush_strategy, }, { .ctl_name = NET_IPV4_CONF_PROMOTE_SECONDARIES, .procname = "promote_secondaries", .data = &ipv4_devconf.promote_secondaries, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &ipv4_doint_and_flush, .strategy = &ipv4_doint_and_flush_strategy, }, }, .devinet_dev = { { .ctl_name = NET_PROTO_CONF_ALL, .procname = "all", .mode = 0555, .child = devinet_sysctl.devinet_vars, }, }, .devinet_conf_dir = { { .ctl_name = NET_IPV4_CONF, .procname = "conf", .mode = 0555, .child = devinet_sysctl.devinet_dev, }, }, .devinet_proto_dir = { { .ctl_name = NET_IPV4, .procname = "ipv4", .mode = 0555, .child = devinet_sysctl.devinet_conf_dir, }, }, .devinet_root_dir = { { .ctl_name = CTL_NET, .procname = "net", .mode = 0555, .child = devinet_sysctl.devinet_proto_dir, }, }, }; static void devinet_sysctl_register(struct in_device *in_dev, struct ipv4_devconf *p) { int i; struct net_device *dev = in_dev ? in_dev->dev : NULL; struct devinet_sysctl_table *t = kmalloc(sizeof(*t), GFP_KERNEL); char *dev_name = NULL; if (!t) return; memcpy(t, &devinet_sysctl, sizeof(*t)); for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) { t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf; t->devinet_vars[i].de = NULL; } if (dev) { dev_name = dev->name; t->devinet_dev[0].ctl_name = dev->ifindex; } else { dev_name = "default"; t->devinet_dev[0].ctl_name = NET_PROTO_CONF_DEFAULT; } /* * Make a copy of dev_name, because '.procname' is regarded as const * by sysctl and we wouldn't want anyone to change it under our feet * (see SIOCSIFNAME). */ dev_name = kstrdup(dev_name, GFP_KERNEL); if (!dev_name) goto free; t->devinet_dev[0].procname = dev_name; t->devinet_dev[0].child = t->devinet_vars; t->devinet_dev[0].de = NULL; t->devinet_conf_dir[0].child = t->devinet_dev; t->devinet_conf_dir[0].de = NULL; t->devinet_proto_dir[0].child = t->devinet_conf_dir; t->devinet_proto_dir[0].de = NULL; t->devinet_root_dir[0].child = t->devinet_proto_dir; t->devinet_root_dir[0].de = NULL; t->sysctl_header = register_sysctl_table(t->devinet_root_dir, 0); if (!t->sysctl_header) goto free_procname; p->sysctl = t; return; /* error path */ free_procname: kfree(dev_name); free: kfree(t); return; } static void devinet_sysctl_unregister(struct ipv4_devconf *p) { if (p->sysctl) { struct devinet_sysctl_table *t = p->sysctl; p->sysctl = NULL; unregister_sysctl_table(t->sysctl_header); kfree(t->devinet_dev[0].procname); kfree(t); } } #endif void __init devinet_init(void) { register_gifconf(PF_INET, inet_gifconf); register_netdevice_notifier(&ip_netdev_notifier); rtnetlink_links[PF_INET] = inet_rtnetlink_table; #ifdef CONFIG_SYSCTL devinet_sysctl.sysctl_header = register_sysctl_table(devinet_sysctl.devinet_root_dir, 0); devinet_sysctl_register(NULL, &ipv4_devconf_dflt); #endif } EXPORT_SYMBOL(devinet_ioctl); EXPORT_SYMBOL(in_dev_finish_destroy); EXPORT_SYMBOL(inet_select_addr); EXPORT_SYMBOL(inetdev_by_index); EXPORT_SYMBOL(register_inetaddr_notifier); EXPORT_SYMBOL(unregister_inetaddr_notifier);