diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/ipv6/anycast.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/ipv6/anycast.c')
-rw-r--r-- | net/ipv6/anycast.c | 594 |
1 files changed, 594 insertions, 0 deletions
diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c new file mode 100644 index 000000000000..5d22ca3cca2e --- /dev/null +++ b/net/ipv6/anycast.c @@ -0,0 +1,594 @@ +/* + * Anycast support for IPv6 + * Linux INET6 implementation + * + * Authors: + * David L Stevens (dlstevens@us.ibm.com) + * + * based heavily on net/ipv6/mcast.c + * + * 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. + */ + +#include <linux/config.h> +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/random.h> +#include <linux/string.h> +#include <linux/socket.h> +#include <linux/sockios.h> +#include <linux/sched.h> +#include <linux/net.h> +#include <linux/in6.h> +#include <linux/netdevice.h> +#include <linux/if_arp.h> +#include <linux/route.h> +#include <linux/init.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> + +#include <net/sock.h> +#include <net/snmp.h> + +#include <net/ipv6.h> +#include <net/protocol.h> +#include <net/if_inet6.h> +#include <net/ndisc.h> +#include <net/addrconf.h> +#include <net/ip6_route.h> + +#include <net/checksum.h> + +static int ipv6_dev_ac_dec(struct net_device *dev, struct in6_addr *addr); + +/* Big ac list lock for all the sockets */ +static DEFINE_RWLOCK(ipv6_sk_ac_lock); + +static int +ip6_onlink(struct in6_addr *addr, struct net_device *dev) +{ + struct inet6_dev *idev; + struct inet6_ifaddr *ifa; + int onlink; + + onlink = 0; + read_lock(&addrconf_lock); + idev = __in6_dev_get(dev); + if (idev) { + read_lock_bh(&idev->lock); + for (ifa=idev->addr_list; ifa; ifa=ifa->if_next) { + onlink = ipv6_prefix_equal(addr, &ifa->addr, + ifa->prefix_len); + if (onlink) + break; + } + read_unlock_bh(&idev->lock); + } + read_unlock(&addrconf_lock); + return onlink; +} + +/* + * socket join an anycast group + */ + +int ipv6_sock_ac_join(struct sock *sk, int ifindex, struct in6_addr *addr) +{ + struct ipv6_pinfo *np = inet6_sk(sk); + struct net_device *dev = NULL; + struct inet6_dev *idev; + struct ipv6_ac_socklist *pac; + int ishost = !ipv6_devconf.forwarding; + int err = 0; + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + if (ipv6_addr_is_multicast(addr)) + return -EINVAL; + if (ipv6_chk_addr(addr, NULL, 0)) + return -EINVAL; + + pac = sock_kmalloc(sk, sizeof(struct ipv6_ac_socklist), GFP_KERNEL); + if (pac == NULL) + return -ENOMEM; + pac->acl_next = NULL; + ipv6_addr_copy(&pac->acl_addr, addr); + + if (ifindex == 0) { + struct rt6_info *rt; + + rt = rt6_lookup(addr, NULL, 0, 0); + if (rt) { + dev = rt->rt6i_dev; + dev_hold(dev); + dst_release(&rt->u.dst); + } else if (ishost) { + err = -EADDRNOTAVAIL; + goto out_free_pac; + } else { + /* router, no matching interface: just pick one */ + + dev = dev_get_by_flags(IFF_UP, IFF_UP|IFF_LOOPBACK); + } + } else + dev = dev_get_by_index(ifindex); + + if (dev == NULL) { + err = -ENODEV; + goto out_free_pac; + } + + idev = in6_dev_get(dev); + if (!idev) { + if (ifindex) + err = -ENODEV; + else + err = -EADDRNOTAVAIL; + goto out_dev_put; + } + /* reset ishost, now that we have a specific device */ + ishost = !idev->cnf.forwarding; + in6_dev_put(idev); + + pac->acl_ifindex = dev->ifindex; + + /* XXX + * For hosts, allow link-local or matching prefix anycasts. + * This obviates the need for propagating anycast routes while + * still allowing some non-router anycast participation. + */ + if (!ip6_onlink(addr, dev)) { + if (ishost) + err = -EADDRNOTAVAIL; + if (err) + goto out_dev_put; + } + + err = ipv6_dev_ac_inc(dev, addr); + if (err) + goto out_dev_put; + + write_lock_bh(&ipv6_sk_ac_lock); + pac->acl_next = np->ipv6_ac_list; + np->ipv6_ac_list = pac; + write_unlock_bh(&ipv6_sk_ac_lock); + + dev_put(dev); + + return 0; + +out_dev_put: + dev_put(dev); +out_free_pac: + sock_kfree_s(sk, pac, sizeof(*pac)); + return err; +} + +/* + * socket leave an anycast group + */ +int ipv6_sock_ac_drop(struct sock *sk, int ifindex, struct in6_addr *addr) +{ + struct ipv6_pinfo *np = inet6_sk(sk); + struct net_device *dev; + struct ipv6_ac_socklist *pac, *prev_pac; + + write_lock_bh(&ipv6_sk_ac_lock); + prev_pac = NULL; + for (pac = np->ipv6_ac_list; pac; pac = pac->acl_next) { + if ((ifindex == 0 || pac->acl_ifindex == ifindex) && + ipv6_addr_equal(&pac->acl_addr, addr)) + break; + prev_pac = pac; + } + if (!pac) { + write_unlock_bh(&ipv6_sk_ac_lock); + return -ENOENT; + } + if (prev_pac) + prev_pac->acl_next = pac->acl_next; + else + np->ipv6_ac_list = pac->acl_next; + + write_unlock_bh(&ipv6_sk_ac_lock); + + dev = dev_get_by_index(pac->acl_ifindex); + if (dev) { + ipv6_dev_ac_dec(dev, &pac->acl_addr); + dev_put(dev); + } + sock_kfree_s(sk, pac, sizeof(*pac)); + return 0; +} + +void ipv6_sock_ac_close(struct sock *sk) +{ + struct ipv6_pinfo *np = inet6_sk(sk); + struct net_device *dev = NULL; + struct ipv6_ac_socklist *pac; + int prev_index; + + write_lock_bh(&ipv6_sk_ac_lock); + pac = np->ipv6_ac_list; + np->ipv6_ac_list = NULL; + write_unlock_bh(&ipv6_sk_ac_lock); + + prev_index = 0; + while (pac) { + struct ipv6_ac_socklist *next = pac->acl_next; + + if (pac->acl_ifindex != prev_index) { + if (dev) + dev_put(dev); + dev = dev_get_by_index(pac->acl_ifindex); + prev_index = pac->acl_ifindex; + } + if (dev) + ipv6_dev_ac_dec(dev, &pac->acl_addr); + sock_kfree_s(sk, pac, sizeof(*pac)); + pac = next; + } + if (dev) + dev_put(dev); +} + +#if 0 +/* The function is not used, which is funny. Apparently, author + * supposed to use it to filter out datagrams inside udp/raw but forgot. + * + * It is OK, anycasts are not special comparing to delivery to unicasts. + */ + +int inet6_ac_check(struct sock *sk, struct in6_addr *addr, int ifindex) +{ + struct ipv6_ac_socklist *pac; + struct ipv6_pinfo *np = inet6_sk(sk); + int found; + + found = 0; + read_lock(&ipv6_sk_ac_lock); + for (pac=np->ipv6_ac_list; pac; pac=pac->acl_next) { + if (ifindex && pac->acl_ifindex != ifindex) + continue; + found = ipv6_addr_equal(&pac->acl_addr, addr); + if (found) + break; + } + read_unlock(&ipv6_sk_ac_lock); + + return found; +} + +#endif + +static void aca_put(struct ifacaddr6 *ac) +{ + if (atomic_dec_and_test(&ac->aca_refcnt)) { + in6_dev_put(ac->aca_idev); + dst_release(&ac->aca_rt->u.dst); + kfree(ac); + } +} + +/* + * device anycast group inc (add if not found) + */ +int ipv6_dev_ac_inc(struct net_device *dev, struct in6_addr *addr) +{ + struct ifacaddr6 *aca; + struct inet6_dev *idev; + struct rt6_info *rt; + int err; + + idev = in6_dev_get(dev); + + if (idev == NULL) + return -EINVAL; + + write_lock_bh(&idev->lock); + if (idev->dead) { + err = -ENODEV; + goto out; + } + + for (aca = idev->ac_list; aca; aca = aca->aca_next) { + if (ipv6_addr_equal(&aca->aca_addr, addr)) { + aca->aca_users++; + err = 0; + goto out; + } + } + + /* + * not found: create a new one. + */ + + aca = kmalloc(sizeof(struct ifacaddr6), GFP_ATOMIC); + + if (aca == NULL) { + err = -ENOMEM; + goto out; + } + + rt = addrconf_dst_alloc(idev, addr, 1); + if (IS_ERR(rt)) { + kfree(aca); + err = PTR_ERR(rt); + goto out; + } + + memset(aca, 0, sizeof(struct ifacaddr6)); + + ipv6_addr_copy(&aca->aca_addr, addr); + aca->aca_idev = idev; + aca->aca_rt = rt; + aca->aca_users = 1; + /* aca_tstamp should be updated upon changes */ + aca->aca_cstamp = aca->aca_tstamp = jiffies; + atomic_set(&aca->aca_refcnt, 2); + spin_lock_init(&aca->aca_lock); + + aca->aca_next = idev->ac_list; + idev->ac_list = aca; + write_unlock_bh(&idev->lock); + + dst_hold(&rt->u.dst); + if (ip6_ins_rt(rt, NULL, NULL)) + dst_release(&rt->u.dst); + + addrconf_join_solict(dev, &aca->aca_addr); + + aca_put(aca); + return 0; +out: + write_unlock_bh(&idev->lock); + in6_dev_put(idev); + return err; +} + +/* + * device anycast group decrement + */ +int __ipv6_dev_ac_dec(struct inet6_dev *idev, struct in6_addr *addr) +{ + struct ifacaddr6 *aca, *prev_aca; + + write_lock_bh(&idev->lock); + prev_aca = NULL; + for (aca = idev->ac_list; aca; aca = aca->aca_next) { + if (ipv6_addr_equal(&aca->aca_addr, addr)) + break; + prev_aca = aca; + } + if (!aca) { + write_unlock_bh(&idev->lock); + return -ENOENT; + } + if (--aca->aca_users > 0) { + write_unlock_bh(&idev->lock); + return 0; + } + if (prev_aca) + prev_aca->aca_next = aca->aca_next; + else + idev->ac_list = aca->aca_next; + write_unlock_bh(&idev->lock); + addrconf_leave_solict(idev, &aca->aca_addr); + + dst_hold(&aca->aca_rt->u.dst); + if (ip6_del_rt(aca->aca_rt, NULL, NULL)) + dst_free(&aca->aca_rt->u.dst); + else + dst_release(&aca->aca_rt->u.dst); + + aca_put(aca); + return 0; +} + +static int ipv6_dev_ac_dec(struct net_device *dev, struct in6_addr *addr) +{ + int ret; + struct inet6_dev *idev = in6_dev_get(dev); + if (idev == NULL) + return -ENODEV; + ret = __ipv6_dev_ac_dec(idev, addr); + in6_dev_put(idev); + return ret; +} + +/* + * check if the interface has this anycast address + */ +static int ipv6_chk_acast_dev(struct net_device *dev, struct in6_addr *addr) +{ + struct inet6_dev *idev; + struct ifacaddr6 *aca; + + idev = in6_dev_get(dev); + if (idev) { + read_lock_bh(&idev->lock); + for (aca = idev->ac_list; aca; aca = aca->aca_next) + if (ipv6_addr_equal(&aca->aca_addr, addr)) + break; + read_unlock_bh(&idev->lock); + in6_dev_put(idev); + return aca != 0; + } + return 0; +} + +/* + * check if given interface (or any, if dev==0) has this anycast address + */ +int ipv6_chk_acast_addr(struct net_device *dev, struct in6_addr *addr) +{ + if (dev) + return ipv6_chk_acast_dev(dev, addr); + read_lock(&dev_base_lock); + for (dev=dev_base; dev; dev=dev->next) + if (ipv6_chk_acast_dev(dev, addr)) + break; + read_unlock(&dev_base_lock); + return dev != 0; +} + + +#ifdef CONFIG_PROC_FS +struct ac6_iter_state { + struct net_device *dev; + struct inet6_dev *idev; +}; + +#define ac6_seq_private(seq) ((struct ac6_iter_state *)(seq)->private) + +static inline struct ifacaddr6 *ac6_get_first(struct seq_file *seq) +{ + struct ifacaddr6 *im = NULL; + struct ac6_iter_state *state = ac6_seq_private(seq); + + for (state->dev = dev_base, state->idev = NULL; + state->dev; + state->dev = state->dev->next) { + struct inet6_dev *idev; + idev = in6_dev_get(state->dev); + if (!idev) + continue; + read_lock_bh(&idev->lock); + im = idev->ac_list; + if (im) { + state->idev = idev; + break; + } + read_unlock_bh(&idev->lock); + } + return im; +} + +static struct ifacaddr6 *ac6_get_next(struct seq_file *seq, struct ifacaddr6 *im) +{ + struct ac6_iter_state *state = ac6_seq_private(seq); + + im = im->aca_next; + while (!im) { + if (likely(state->idev != NULL)) { + read_unlock_bh(&state->idev->lock); + in6_dev_put(state->idev); + } + state->dev = state->dev->next; + if (!state->dev) { + state->idev = NULL; + break; + } + state->idev = in6_dev_get(state->dev); + if (!state->idev) + continue; + read_lock_bh(&state->idev->lock); + im = state->idev->ac_list; + } + return im; +} + +static struct ifacaddr6 *ac6_get_idx(struct seq_file *seq, loff_t pos) +{ + struct ifacaddr6 *im = ac6_get_first(seq); + if (im) + while (pos && (im = ac6_get_next(seq, im)) != NULL) + --pos; + return pos ? NULL : im; +} + +static void *ac6_seq_start(struct seq_file *seq, loff_t *pos) +{ + read_lock(&dev_base_lock); + return ac6_get_idx(seq, *pos); +} + +static void *ac6_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + struct ifacaddr6 *im; + im = ac6_get_next(seq, v); + ++*pos; + return im; +} + +static void ac6_seq_stop(struct seq_file *seq, void *v) +{ + struct ac6_iter_state *state = ac6_seq_private(seq); + if (likely(state->idev != NULL)) { + read_unlock_bh(&state->idev->lock); + in6_dev_put(state->idev); + } + read_unlock(&dev_base_lock); +} + +static int ac6_seq_show(struct seq_file *seq, void *v) +{ + struct ifacaddr6 *im = (struct ifacaddr6 *)v; + struct ac6_iter_state *state = ac6_seq_private(seq); + + seq_printf(seq, + "%-4d %-15s " + "%04x%04x%04x%04x%04x%04x%04x%04x " + "%5d\n", + state->dev->ifindex, state->dev->name, + NIP6(im->aca_addr), + im->aca_users); + return 0; +} + +static struct seq_operations ac6_seq_ops = { + .start = ac6_seq_start, + .next = ac6_seq_next, + .stop = ac6_seq_stop, + .show = ac6_seq_show, +}; + +static int ac6_seq_open(struct inode *inode, struct file *file) +{ + struct seq_file *seq; + int rc = -ENOMEM; + struct ac6_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL); + + if (!s) + goto out; + + rc = seq_open(file, &ac6_seq_ops); + if (rc) + goto out_kfree; + + seq = file->private_data; + seq->private = s; + memset(s, 0, sizeof(*s)); +out: + return rc; +out_kfree: + kfree(s); + goto out; +} + +static struct file_operations ac6_seq_fops = { + .owner = THIS_MODULE, + .open = ac6_seq_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release_private, +}; + +int __init ac6_proc_init(void) +{ + if (!proc_net_fops_create("anycast6", S_IRUGO, &ac6_seq_fops)) + return -ENOMEM; + + return 0; +} + +void ac6_proc_exit(void) +{ + proc_net_remove("anycast6"); +} +#endif + |