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-rw-r--r--net/ipv6/ip6_flowlabel.c706
1 files changed, 706 insertions, 0 deletions
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
new file mode 100644
index 000000000000..a93f6dc51979
--- /dev/null
+++ b/net/ipv6/ip6_flowlabel.c
@@ -0,0 +1,706 @@
+/*
+ * ip6_flowlabel.c IPv6 flowlabel manager.
+ *
+ * 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.
+ *
+ * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/in6.h>
+#include <linux/route.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+#include <net/sock.h>
+
+#include <net/ipv6.h>
+#include <net/ndisc.h>
+#include <net/protocol.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/rawv6.h>
+#include <net/icmp.h>
+#include <net/transp_v6.h>
+
+#include <asm/uaccess.h>
+
+#define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified
+ in old IPv6 RFC. Well, it was reasonable value.
+ */
+#define FL_MAX_LINGER 60 /* Maximal linger timeout */
+
+/* FL hash table */
+
+#define FL_MAX_PER_SOCK 32
+#define FL_MAX_SIZE 4096
+#define FL_HASH_MASK 255
+#define FL_HASH(l) (ntohl(l)&FL_HASH_MASK)
+
+static atomic_t fl_size = ATOMIC_INIT(0);
+static struct ip6_flowlabel *fl_ht[FL_HASH_MASK+1];
+
+static void ip6_fl_gc(unsigned long dummy);
+static struct timer_list ip6_fl_gc_timer = TIMER_INITIALIZER(ip6_fl_gc, 0, 0);
+
+/* FL hash table lock: it protects only of GC */
+
+static DEFINE_RWLOCK(ip6_fl_lock);
+
+/* Big socket sock */
+
+static DEFINE_RWLOCK(ip6_sk_fl_lock);
+
+
+static __inline__ struct ip6_flowlabel * __fl_lookup(u32 label)
+{
+ struct ip6_flowlabel *fl;
+
+ for (fl=fl_ht[FL_HASH(label)]; fl; fl = fl->next) {
+ if (fl->label == label)
+ return fl;
+ }
+ return NULL;
+}
+
+static struct ip6_flowlabel * fl_lookup(u32 label)
+{
+ struct ip6_flowlabel *fl;
+
+ read_lock_bh(&ip6_fl_lock);
+ fl = __fl_lookup(label);
+ if (fl)
+ atomic_inc(&fl->users);
+ read_unlock_bh(&ip6_fl_lock);
+ return fl;
+}
+
+
+static void fl_free(struct ip6_flowlabel *fl)
+{
+ if (fl)
+ kfree(fl->opt);
+ kfree(fl);
+}
+
+static void fl_release(struct ip6_flowlabel *fl)
+{
+ write_lock_bh(&ip6_fl_lock);
+
+ fl->lastuse = jiffies;
+ if (atomic_dec_and_test(&fl->users)) {
+ unsigned long ttd = fl->lastuse + fl->linger;
+ if (time_after(ttd, fl->expires))
+ fl->expires = ttd;
+ ttd = fl->expires;
+ if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
+ struct ipv6_txoptions *opt = fl->opt;
+ fl->opt = NULL;
+ kfree(opt);
+ }
+ if (!timer_pending(&ip6_fl_gc_timer) ||
+ time_after(ip6_fl_gc_timer.expires, ttd))
+ mod_timer(&ip6_fl_gc_timer, ttd);
+ }
+
+ write_unlock_bh(&ip6_fl_lock);
+}
+
+static void ip6_fl_gc(unsigned long dummy)
+{
+ int i;
+ unsigned long now = jiffies;
+ unsigned long sched = 0;
+
+ write_lock(&ip6_fl_lock);
+
+ for (i=0; i<=FL_HASH_MASK; i++) {
+ struct ip6_flowlabel *fl, **flp;
+ flp = &fl_ht[i];
+ while ((fl=*flp) != NULL) {
+ if (atomic_read(&fl->users) == 0) {
+ unsigned long ttd = fl->lastuse + fl->linger;
+ if (time_after(ttd, fl->expires))
+ fl->expires = ttd;
+ ttd = fl->expires;
+ if (time_after_eq(now, ttd)) {
+ *flp = fl->next;
+ fl_free(fl);
+ atomic_dec(&fl_size);
+ continue;
+ }
+ if (!sched || time_before(ttd, sched))
+ sched = ttd;
+ }
+ flp = &fl->next;
+ }
+ }
+ if (!sched && atomic_read(&fl_size))
+ sched = now + FL_MAX_LINGER;
+ if (sched) {
+ ip6_fl_gc_timer.expires = sched;
+ add_timer(&ip6_fl_gc_timer);
+ }
+ write_unlock(&ip6_fl_lock);
+}
+
+static int fl_intern(struct ip6_flowlabel *fl, __u32 label)
+{
+ fl->label = label & IPV6_FLOWLABEL_MASK;
+
+ write_lock_bh(&ip6_fl_lock);
+ if (label == 0) {
+ for (;;) {
+ fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
+ if (fl->label) {
+ struct ip6_flowlabel *lfl;
+ lfl = __fl_lookup(fl->label);
+ if (lfl == NULL)
+ break;
+ }
+ }
+ }
+
+ fl->lastuse = jiffies;
+ fl->next = fl_ht[FL_HASH(fl->label)];
+ fl_ht[FL_HASH(fl->label)] = fl;
+ atomic_inc(&fl_size);
+ write_unlock_bh(&ip6_fl_lock);
+ return 0;
+}
+
+
+
+/* Socket flowlabel lists */
+
+struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, u32 label)
+{
+ struct ipv6_fl_socklist *sfl;
+ struct ipv6_pinfo *np = inet6_sk(sk);
+
+ label &= IPV6_FLOWLABEL_MASK;
+
+ for (sfl=np->ipv6_fl_list; sfl; sfl = sfl->next) {
+ struct ip6_flowlabel *fl = sfl->fl;
+ if (fl->label == label) {
+ fl->lastuse = jiffies;
+ atomic_inc(&fl->users);
+ return fl;
+ }
+ }
+ return NULL;
+}
+
+void fl6_free_socklist(struct sock *sk)
+{
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct ipv6_fl_socklist *sfl;
+
+ while ((sfl = np->ipv6_fl_list) != NULL) {
+ np->ipv6_fl_list = sfl->next;
+ fl_release(sfl->fl);
+ kfree(sfl);
+ }
+}
+
+/* Service routines */
+
+
+/*
+ It is the only difficult place. flowlabel enforces equal headers
+ before and including routing header, however user may supply options
+ following rthdr.
+ */
+
+struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
+ struct ip6_flowlabel * fl,
+ struct ipv6_txoptions * fopt)
+{
+ struct ipv6_txoptions * fl_opt = fl->opt;
+
+ if (fopt == NULL || fopt->opt_flen == 0)
+ return fl_opt;
+
+ if (fl_opt != NULL) {
+ opt_space->hopopt = fl_opt->hopopt;
+ opt_space->dst0opt = fl_opt->dst0opt;
+ opt_space->srcrt = fl_opt->srcrt;
+ opt_space->opt_nflen = fl_opt->opt_nflen;
+ } else {
+ if (fopt->opt_nflen == 0)
+ return fopt;
+ opt_space->hopopt = NULL;
+ opt_space->dst0opt = NULL;
+ opt_space->srcrt = NULL;
+ opt_space->opt_nflen = 0;
+ }
+ opt_space->dst1opt = fopt->dst1opt;
+ opt_space->auth = fopt->auth;
+ opt_space->opt_flen = fopt->opt_flen;
+ return opt_space;
+}
+
+static unsigned long check_linger(unsigned long ttl)
+{
+ if (ttl < FL_MIN_LINGER)
+ return FL_MIN_LINGER*HZ;
+ if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
+ return 0;
+ return ttl*HZ;
+}
+
+static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
+{
+ linger = check_linger(linger);
+ if (!linger)
+ return -EPERM;
+ expires = check_linger(expires);
+ if (!expires)
+ return -EPERM;
+ fl->lastuse = jiffies;
+ if (time_before(fl->linger, linger))
+ fl->linger = linger;
+ if (time_before(expires, fl->linger))
+ expires = fl->linger;
+ if (time_before(fl->expires, fl->lastuse + expires))
+ fl->expires = fl->lastuse + expires;
+ return 0;
+}
+
+static struct ip6_flowlabel *
+fl_create(struct in6_flowlabel_req *freq, char __user *optval, int optlen, int *err_p)
+{
+ struct ip6_flowlabel *fl;
+ int olen;
+ int addr_type;
+ int err;
+
+ err = -ENOMEM;
+ fl = kmalloc(sizeof(*fl), GFP_KERNEL);
+ if (fl == NULL)
+ goto done;
+ memset(fl, 0, sizeof(*fl));
+
+ olen = optlen - CMSG_ALIGN(sizeof(*freq));
+ if (olen > 0) {
+ struct msghdr msg;
+ struct flowi flowi;
+ int junk;
+
+ err = -ENOMEM;
+ fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
+ if (fl->opt == NULL)
+ goto done;
+
+ memset(fl->opt, 0, sizeof(*fl->opt));
+ fl->opt->tot_len = sizeof(*fl->opt) + olen;
+ err = -EFAULT;
+ if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
+ goto done;
+
+ msg.msg_controllen = olen;
+ msg.msg_control = (void*)(fl->opt+1);
+ flowi.oif = 0;
+
+ err = datagram_send_ctl(&msg, &flowi, fl->opt, &junk);
+ if (err)
+ goto done;
+ err = -EINVAL;
+ if (fl->opt->opt_flen)
+ goto done;
+ if (fl->opt->opt_nflen == 0) {
+ kfree(fl->opt);
+ fl->opt = NULL;
+ }
+ }
+
+ fl->expires = jiffies;
+ err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
+ if (err)
+ goto done;
+ fl->share = freq->flr_share;
+ addr_type = ipv6_addr_type(&freq->flr_dst);
+ if ((addr_type&IPV6_ADDR_MAPPED)
+ || addr_type == IPV6_ADDR_ANY)
+ goto done;
+ ipv6_addr_copy(&fl->dst, &freq->flr_dst);
+ atomic_set(&fl->users, 1);
+ switch (fl->share) {
+ case IPV6_FL_S_EXCL:
+ case IPV6_FL_S_ANY:
+ break;
+ case IPV6_FL_S_PROCESS:
+ fl->owner = current->pid;
+ break;
+ case IPV6_FL_S_USER:
+ fl->owner = current->euid;
+ break;
+ default:
+ err = -EINVAL;
+ goto done;
+ }
+ return fl;
+
+done:
+ fl_free(fl);
+ *err_p = err;
+ return NULL;
+}
+
+static int mem_check(struct sock *sk)
+{
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct ipv6_fl_socklist *sfl;
+ int room = FL_MAX_SIZE - atomic_read(&fl_size);
+ int count = 0;
+
+ if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
+ return 0;
+
+ for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next)
+ count++;
+
+ if (room <= 0 ||
+ ((count >= FL_MAX_PER_SOCK ||
+ (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4)
+ && !capable(CAP_NET_ADMIN)))
+ return -ENOBUFS;
+
+ return 0;
+}
+
+static int ipv6_hdr_cmp(struct ipv6_opt_hdr *h1, struct ipv6_opt_hdr *h2)
+{
+ if (h1 == h2)
+ return 0;
+ if (h1 == NULL || h2 == NULL)
+ return 1;
+ if (h1->hdrlen != h2->hdrlen)
+ return 1;
+ return memcmp(h1+1, h2+1, ((h1->hdrlen+1)<<3) - sizeof(*h1));
+}
+
+static int ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2)
+{
+ if (o1 == o2)
+ return 0;
+ if (o1 == NULL || o2 == NULL)
+ return 1;
+ if (o1->opt_nflen != o2->opt_nflen)
+ return 1;
+ if (ipv6_hdr_cmp(o1->hopopt, o2->hopopt))
+ return 1;
+ if (ipv6_hdr_cmp(o1->dst0opt, o2->dst0opt))
+ return 1;
+ if (ipv6_hdr_cmp((struct ipv6_opt_hdr *)o1->srcrt, (struct ipv6_opt_hdr *)o2->srcrt))
+ return 1;
+ return 0;
+}
+
+int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
+{
+ int err;
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct in6_flowlabel_req freq;
+ struct ipv6_fl_socklist *sfl1=NULL;
+ struct ipv6_fl_socklist *sfl, **sflp;
+ struct ip6_flowlabel *fl;
+
+ if (optlen < sizeof(freq))
+ return -EINVAL;
+
+ if (copy_from_user(&freq, optval, sizeof(freq)))
+ return -EFAULT;
+
+ switch (freq.flr_action) {
+ case IPV6_FL_A_PUT:
+ write_lock_bh(&ip6_sk_fl_lock);
+ for (sflp = &np->ipv6_fl_list; (sfl=*sflp)!=NULL; sflp = &sfl->next) {
+ if (sfl->fl->label == freq.flr_label) {
+ if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
+ np->flow_label &= ~IPV6_FLOWLABEL_MASK;
+ *sflp = sfl->next;
+ write_unlock_bh(&ip6_sk_fl_lock);
+ fl_release(sfl->fl);
+ kfree(sfl);
+ return 0;
+ }
+ }
+ write_unlock_bh(&ip6_sk_fl_lock);
+ return -ESRCH;
+
+ case IPV6_FL_A_RENEW:
+ read_lock_bh(&ip6_sk_fl_lock);
+ for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
+ if (sfl->fl->label == freq.flr_label) {
+ err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
+ read_unlock_bh(&ip6_sk_fl_lock);
+ return err;
+ }
+ }
+ read_unlock_bh(&ip6_sk_fl_lock);
+
+ if (freq.flr_share == IPV6_FL_S_NONE && capable(CAP_NET_ADMIN)) {
+ fl = fl_lookup(freq.flr_label);
+ if (fl) {
+ err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
+ fl_release(fl);
+ return err;
+ }
+ }
+ return -ESRCH;
+
+ case IPV6_FL_A_GET:
+ if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
+ return -EINVAL;
+
+ fl = fl_create(&freq, optval, optlen, &err);
+ if (fl == NULL)
+ return err;
+ sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
+
+ if (freq.flr_label) {
+ struct ip6_flowlabel *fl1 = NULL;
+
+ err = -EEXIST;
+ read_lock_bh(&ip6_sk_fl_lock);
+ for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
+ if (sfl->fl->label == freq.flr_label) {
+ if (freq.flr_flags&IPV6_FL_F_EXCL) {
+ read_unlock_bh(&ip6_sk_fl_lock);
+ goto done;
+ }
+ fl1 = sfl->fl;
+ atomic_inc(&fl->users);
+ break;
+ }
+ }
+ read_unlock_bh(&ip6_sk_fl_lock);
+
+ if (fl1 == NULL)
+ fl1 = fl_lookup(freq.flr_label);
+ if (fl1) {
+ err = -EEXIST;
+ if (freq.flr_flags&IPV6_FL_F_EXCL)
+ goto release;
+ err = -EPERM;
+ if (fl1->share == IPV6_FL_S_EXCL ||
+ fl1->share != fl->share ||
+ fl1->owner != fl->owner)
+ goto release;
+
+ err = -EINVAL;
+ if (!ipv6_addr_equal(&fl1->dst, &fl->dst) ||
+ ipv6_opt_cmp(fl1->opt, fl->opt))
+ goto release;
+
+ err = -ENOMEM;
+ if (sfl1 == NULL)
+ goto release;
+ if (fl->linger > fl1->linger)
+ fl1->linger = fl->linger;
+ if ((long)(fl->expires - fl1->expires) > 0)
+ fl1->expires = fl->expires;
+ write_lock_bh(&ip6_sk_fl_lock);
+ sfl1->fl = fl1;
+ sfl1->next = np->ipv6_fl_list;
+ np->ipv6_fl_list = sfl1;
+ write_unlock_bh(&ip6_sk_fl_lock);
+ fl_free(fl);
+ return 0;
+
+release:
+ fl_release(fl1);
+ goto done;
+ }
+ }
+ err = -ENOENT;
+ if (!(freq.flr_flags&IPV6_FL_F_CREATE))
+ goto done;
+
+ err = -ENOMEM;
+ if (sfl1 == NULL || (err = mem_check(sk)) != 0)
+ goto done;
+
+ err = fl_intern(fl, freq.flr_label);
+ if (err)
+ goto done;
+
+ /* Do not check for fault */
+ if (!freq.flr_label)
+ copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
+ &fl->label, sizeof(fl->label));
+
+ sfl1->fl = fl;
+ sfl1->next = np->ipv6_fl_list;
+ np->ipv6_fl_list = sfl1;
+ return 0;
+
+ default:
+ return -EINVAL;
+ }
+
+done:
+ fl_free(fl);
+ kfree(sfl1);
+ return err;
+}
+
+#ifdef CONFIG_PROC_FS
+
+struct ip6fl_iter_state {
+ int bucket;
+};
+
+#define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private)
+
+static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
+{
+ struct ip6_flowlabel *fl = NULL;
+ struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
+
+ for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
+ if (fl_ht[state->bucket]) {
+ fl = fl_ht[state->bucket];
+ break;
+ }
+ }
+ return fl;
+}
+
+static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
+{
+ struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
+
+ fl = fl->next;
+ while (!fl) {
+ if (++state->bucket <= FL_HASH_MASK)
+ fl = fl_ht[state->bucket];
+ }
+ return fl;
+}
+
+static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
+{
+ struct ip6_flowlabel *fl = ip6fl_get_first(seq);
+ if (fl)
+ while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
+ --pos;
+ return pos ? NULL : fl;
+}
+
+static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ read_lock_bh(&ip6_fl_lock);
+ return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
+}
+
+static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct ip6_flowlabel *fl;
+
+ if (v == SEQ_START_TOKEN)
+ fl = ip6fl_get_first(seq);
+ else
+ fl = ip6fl_get_next(seq, v);
+ ++*pos;
+ return fl;
+}
+
+static void ip6fl_seq_stop(struct seq_file *seq, void *v)
+{
+ read_unlock_bh(&ip6_fl_lock);
+}
+
+static void ip6fl_fl_seq_show(struct seq_file *seq, struct ip6_flowlabel *fl)
+{
+ while(fl) {
+ seq_printf(seq,
+ "%05X %-1d %-6d %-6d %-6ld %-8ld "
+ "%02x%02x%02x%02x%02x%02x%02x%02x "
+ "%-4d\n",
+ (unsigned)ntohl(fl->label),
+ fl->share,
+ (unsigned)fl->owner,
+ atomic_read(&fl->users),
+ fl->linger/HZ,
+ (long)(fl->expires - jiffies)/HZ,
+ NIP6(fl->dst),
+ fl->opt ? fl->opt->opt_nflen : 0);
+ fl = fl->next;
+ }
+}
+
+static int ip6fl_seq_show(struct seq_file *seq, void *v)
+{
+ if (v == SEQ_START_TOKEN)
+ seq_puts(seq, "Label S Owner Users Linger Expires "
+ "Dst Opt\n");
+ else
+ ip6fl_fl_seq_show(seq, v);
+ return 0;
+}
+
+static struct seq_operations ip6fl_seq_ops = {
+ .start = ip6fl_seq_start,
+ .next = ip6fl_seq_next,
+ .stop = ip6fl_seq_stop,
+ .show = ip6fl_seq_show,
+};
+
+static int ip6fl_seq_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq;
+ int rc = -ENOMEM;
+ struct ip6fl_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
+
+ if (!s)
+ goto out;
+
+ rc = seq_open(file, &ip6fl_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 ip6fl_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = ip6fl_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_private,
+};
+#endif
+
+
+void ip6_flowlabel_init(void)
+{
+#ifdef CONFIG_PROC_FS
+ proc_net_fops_create("ip6_flowlabel", S_IRUGO, &ip6fl_seq_fops);
+#endif
+}
+
+void ip6_flowlabel_cleanup(void)
+{
+ del_timer(&ip6_fl_gc_timer);
+#ifdef CONFIG_PROC_FS
+ proc_net_remove("ip6_flowlabel");
+#endif
+}