This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / net / netfilter / nf_sockopt.c

diff --git a/net/netfilter/nf_sockopt.c b/net/netfilter/nf_sockopt.c
new file mode 100644 (file)
index 0000000..0a63d7d
--- /dev/null
+++ b/net/netfilter/nf_sockopt.c
@@ -0,0 +1,202 @@
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/netfilter.h>
+#include <linux/mutex.h>
+#include <net/sock.h>
+
+#include "nf_internals.h"
+
+/* Sockopts only registered and called from user context, so
+   net locking would be overkill.  Also, [gs]etsockopt calls may
+   sleep. */
+static DEFINE_MUTEX(nf_sockopt_mutex);
+static LIST_HEAD(nf_sockopts);
+
+/* Do exclusive ranges overlap? */
+static inline int overlap(int min1, int max1, int min2, int max2)
+{
+       return max1 > min2 && min1 < max2;
+}
+
+/* Functions to register sockopt ranges (exclusive). */
+int nf_register_sockopt(struct nf_sockopt_ops *reg)
+{
+       struct list_head *i;
+       int ret = 0;
+
+       if (mutex_lock_interruptible(&nf_sockopt_mutex) != 0)
+               return -EINTR;
+
+       list_for_each(i, &nf_sockopts) {
+               struct nf_sockopt_ops *ops = (struct nf_sockopt_ops *)i;
+               if (ops->pf == reg->pf
+                   && (overlap(ops->set_optmin, ops->set_optmax, 
+                               reg->set_optmin, reg->set_optmax)
+                       || overlap(ops->get_optmin, ops->get_optmax, 
+                                  reg->get_optmin, reg->get_optmax))) {
+                       NFDEBUG("nf_sock overlap: %u-%u/%u-%u v %u-%u/%u-%u\n",
+                               ops->set_optmin, ops->set_optmax, 
+                               ops->get_optmin, ops->get_optmax, 
+                               reg->set_optmin, reg->set_optmax,
+                               reg->get_optmin, reg->get_optmax);
+                       ret = -EBUSY;
+                       goto out;
+               }
+       }
+
+       list_add(&reg->list, &nf_sockopts);
+out:
+       mutex_unlock(&nf_sockopt_mutex);
+       return ret;
+}
+EXPORT_SYMBOL(nf_register_sockopt);
+
+void nf_unregister_sockopt(struct nf_sockopt_ops *reg)
+{
+       /* No point being interruptible: we're probably in cleanup_module() */
+ restart:
+       mutex_lock(&nf_sockopt_mutex);
+       if (reg->use != 0) {
+               /* To be woken by nf_sockopt call... */
+               /* FIXME: Stuart Young's name appears gratuitously. */
+               set_current_state(TASK_UNINTERRUPTIBLE);
+               reg->cleanup_task = current;
+               mutex_unlock(&nf_sockopt_mutex);
+               schedule();
+               goto restart;
+       }
+       list_del(&reg->list);
+       mutex_unlock(&nf_sockopt_mutex);
+}
+EXPORT_SYMBOL(nf_unregister_sockopt);
+
+/* Call get/setsockopt() */
+static int nf_sockopt(struct sock *sk, int pf, int val, 
+                     char __user *opt, int *len, int get)
+{
+       struct list_head *i;
+       struct nf_sockopt_ops *ops;
+       int ret;
+
+       if (mutex_lock_interruptible(&nf_sockopt_mutex) != 0)
+               return -EINTR;
+
+       list_for_each(i, &nf_sockopts) {
+               ops = (struct nf_sockopt_ops *)i;
+               if (ops->pf == pf) {
+                       if (get) {
+                               if (val >= ops->get_optmin
+                                   && val < ops->get_optmax) {
+                                       ops->use++;
+                                       mutex_unlock(&nf_sockopt_mutex);
+                                       ret = ops->get(sk, val, opt, len);
+                                       goto out;
+                               }
+                       } else {
+                               if (val >= ops->set_optmin
+                                   && val < ops->set_optmax) {
+                                       ops->use++;
+                                       mutex_unlock(&nf_sockopt_mutex);
+                                       ret = ops->set(sk, val, opt, *len);
+                                       goto out;
+                               }
+                       }
+               }
+       }
+       mutex_unlock(&nf_sockopt_mutex);
+       return -ENOPROTOOPT;
+       
+ out:
+       mutex_lock(&nf_sockopt_mutex);
+       ops->use--;
+       if (ops->cleanup_task)
+               wake_up_process(ops->cleanup_task);
+       mutex_unlock(&nf_sockopt_mutex);
+       return ret;
+}
+
+int nf_setsockopt(struct sock *sk, int pf, int val, char __user *opt,
+                 int len)
+{
+       return nf_sockopt(sk, pf, val, opt, &len, 0);
+}
+EXPORT_SYMBOL(nf_setsockopt);
+
+int nf_getsockopt(struct sock *sk, int pf, int val, char __user *opt, int *len)
+{
+       return nf_sockopt(sk, pf, val, opt, len, 1);
+}
+EXPORT_SYMBOL(nf_getsockopt);
+
+#ifdef CONFIG_COMPAT
+static int compat_nf_sockopt(struct sock *sk, int pf, int val,
+                            char __user *opt, int *len, int get)
+{
+       struct list_head *i;
+       struct nf_sockopt_ops *ops;
+       int ret;
+
+       if (mutex_lock_interruptible(&nf_sockopt_mutex) != 0)
+               return -EINTR;
+
+       list_for_each(i, &nf_sockopts) {
+               ops = (struct nf_sockopt_ops *)i;
+               if (ops->pf == pf) {
+                       if (get) {
+                               if (val >= ops->get_optmin
+                                   && val < ops->get_optmax) {
+                                       ops->use++;
+                                       mutex_unlock(&nf_sockopt_mutex);
+                                       if (ops->compat_get)
+                                               ret = ops->compat_get(sk,
+                                                       val, opt, len);
+                                       else
+                                               ret = ops->get(sk,
+                                                       val, opt, len);
+                                       goto out;
+                               }
+                       } else {
+                               if (val >= ops->set_optmin
+                                   && val < ops->set_optmax) {
+                                       ops->use++;
+                                       mutex_unlock(&nf_sockopt_mutex);
+                                       if (ops->compat_set)
+                                               ret = ops->compat_set(sk,
+                                                       val, opt, *len);
+                                       else
+                                               ret = ops->set(sk,
+                                                       val, opt, *len);
+                                       goto out;
+                               }
+                       }
+               }
+       }
+       mutex_unlock(&nf_sockopt_mutex);
+       return -ENOPROTOOPT;
+
+ out:
+       mutex_lock(&nf_sockopt_mutex);
+       ops->use--;
+       if (ops->cleanup_task)
+               wake_up_process(ops->cleanup_task);
+       mutex_unlock(&nf_sockopt_mutex);
+       return ret;
+}
+
+int compat_nf_setsockopt(struct sock *sk, int pf,
+               int val, char __user *opt, int len)
+{
+       return compat_nf_sockopt(sk, pf, val, opt, &len, 0);
+}
+EXPORT_SYMBOL(compat_nf_setsockopt);
+
+int compat_nf_getsockopt(struct sock *sk, int pf,
+               int val, char __user *opt, int *len)
+{
+       return compat_nf_sockopt(sk, pf, val, opt, len, 1);
+}
+EXPORT_SYMBOL(compat_nf_getsockopt);
+#endif