Import of Linux 2.2.12 subset (ipv4 stack and related)

1 files changed, 322 insertions, 0 deletions

diff --git a/pfinet/linux-src/net/ipv4/ip_masq_mod.c b/pfinet/linux-src/net/ipv4/ip_masq_mod.c
new file mode 100644
index 00000000..b99502f3
--- /dev/null
+++ b/pfinet/linux-src/net/ipv4/ip_masq_mod.c
@@ -0,0 +1,322 @@
+/*
+ *		IP_MASQ_MOD masq modules support
+ *
+ *
+ * Author:	Juan Jose Ciarlante, <jjciarla@raiz.uncu.edu.ar>
+ *
+ * 	$Id: ip_masq_mod.c,v 1.5.2.1 1999/07/02 10:10:03 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.
+ *
+ * Changes:
+ *		Cyrus Durgin:		fixed kerneld stuff for kmod.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <net/ip_masq.h>
+#include <net/ip_masq_mod.h>
+
+#include <linux/ip_masq.h>
+#ifdef CONFIG_KMOD
+#include <linux/kmod.h>
+#endif
+
+EXPORT_SYMBOL(register_ip_masq_mod);
+EXPORT_SYMBOL(unregister_ip_masq_mod);
+EXPORT_SYMBOL(ip_masq_mod_lkp_link);
+EXPORT_SYMBOL(ip_masq_mod_lkp_unlink);
+
+static spinlock_t masq_mod_lock = SPIN_LOCK_UNLOCKED;
+
+/*
+ *	Base pointer for registered modules
+ */
+struct ip_masq_mod * ip_masq_mod_reg_base = NULL;
+
+/*
+ *	Base pointer for lookup (subset of above, a module could be
+ *	registered, but it could have no active rule); will avoid
+ *	unnecessary lookups.
+ */
+struct ip_masq_mod * ip_masq_mod_lkp_base = NULL;
+
+int ip_masq_mod_register_proc(struct ip_masq_mod *mmod)
+{
+#ifdef CONFIG_PROC_FS        
+	int ret;
+
+	struct proc_dir_entry *ent = mmod->mmod_proc_ent;
+
+	if (!ent) 
+		return 0;
+	if (!ent->name) {
+		ent->name = mmod->mmod_name;
+		ent->namelen = strlen (mmod->mmod_name);
+	}
+	ret = ip_masq_proc_register(ent);
+	if (ret) mmod->mmod_proc_ent = NULL;
+
+	return ret;
+#else
+	return 0;
+#endif
+}
+
+void ip_masq_mod_unregister_proc(struct ip_masq_mod *mmod)
+{
+#ifdef CONFIG_PROC_FS        
+	struct proc_dir_entry *ent = mmod->mmod_proc_ent;
+	if (!ent)
+		return;
+	ip_masq_proc_unregister(ent);
+#endif
+}
+
+/*
+ *	Link/unlink object for lookups
+ */
+
+int ip_masq_mod_lkp_unlink(struct ip_masq_mod *mmod)
+{
+	struct ip_masq_mod **mmod_p;
+
+	write_lock_bh(&masq_mod_lock);
+
+	for (mmod_p = &ip_masq_mod_lkp_base; *mmod_p ; mmod_p = &(*mmod_p)->next)
+		if (mmod == (*mmod_p))  {
+			*mmod_p = mmod->next;
+			mmod->next = NULL;
+			write_unlock_bh(&masq_mod_lock);
+			return 0;
+		}
+
+	write_unlock_bh(&masq_mod_lock);
+	return -EINVAL;
+}
+
+int ip_masq_mod_lkp_link(struct ip_masq_mod *mmod)
+{
+	write_lock_bh(&masq_mod_lock);
+
+	mmod->next = ip_masq_mod_lkp_base;
+	ip_masq_mod_lkp_base=mmod;
+
+	write_unlock_bh(&masq_mod_lock);
+	return 0;
+}
+
+int register_ip_masq_mod(struct ip_masq_mod *mmod)
+{
+	if (!mmod) {
+		IP_MASQ_ERR("register_ip_masq_mod(): NULL arg\n");
+		return -EINVAL;
+	}
+	if (!mmod->mmod_name) {
+		IP_MASQ_ERR("register_ip_masq_mod(): NULL mmod_name\n");
+		return -EINVAL;
+	}
+	ip_masq_mod_register_proc(mmod);
+
+	mmod->next_reg = ip_masq_mod_reg_base;
+	ip_masq_mod_reg_base=mmod;
+
+	return 0;
+}
+
+int unregister_ip_masq_mod(struct ip_masq_mod *mmod)
+{
+	struct ip_masq_mod **mmod_p;
+
+	if (!mmod) {
+		IP_MASQ_ERR( "unregister_ip_masq_mod(): NULL arg\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * 	Only allow unregistration if it is not referenced
+	 */
+	if (atomic_read(&mmod->refcnt))  {
+		IP_MASQ_ERR( "unregister_ip_masq_mod(): is in use by %d guys. failed\n",
+				atomic_read(&mmod->refcnt));
+		return -EINVAL;
+	}
+
+	/*	
+	 *	Must be already unlinked from lookup list
+	 */
+	if (mmod->next) {
+		IP_MASQ_WARNING("MASQ: unregistering \"%s\" while in lookup list.fixed.",
+			mmod->mmod_name);
+		ip_masq_mod_lkp_unlink(mmod);
+	}
+
+	for (mmod_p = &ip_masq_mod_reg_base; *mmod_p ; mmod_p = &(*mmod_p)->next_reg)
+		if (mmod == (*mmod_p))  {
+			ip_masq_mod_unregister_proc(mmod);
+			*mmod_p = mmod->next_reg;
+			return 0;
+		}
+
+	IP_MASQ_ERR("unregister_ip_masq_mod(%s): not linked \n", mmod->mmod_name);
+	return -EINVAL;
+}
+
+int ip_masq_mod_in_rule(const struct sk_buff *skb, const struct iphdr *iph)
+{
+	struct ip_masq_mod *mmod;
+	int ret = IP_MASQ_MOD_NOP;
+
+	for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
+		if (!mmod->mmod_in_rule) continue;
+		switch (ret=mmod->mmod_in_rule(skb, iph)) {
+			case IP_MASQ_MOD_NOP:
+				continue;
+			case IP_MASQ_MOD_ACCEPT:
+			case IP_MASQ_MOD_REJECT:
+				goto out;
+		}
+	}
+out:
+	return ret;
+}
+
+int ip_masq_mod_out_rule(const struct sk_buff *skb, const struct iphdr *iph)
+{
+	struct ip_masq_mod *mmod;
+	int ret = IP_MASQ_MOD_NOP;
+
+	for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
+		if (!mmod->mmod_out_rule) continue;
+		switch (ret=mmod->mmod_out_rule(skb, iph)) {
+			case IP_MASQ_MOD_NOP:
+				continue;
+			case IP_MASQ_MOD_ACCEPT:
+			case IP_MASQ_MOD_REJECT:
+				goto out;
+		}
+	}
+out:
+	return ret;
+}
+
+struct ip_masq * ip_masq_mod_in_create(const struct sk_buff *skb, const struct iphdr *iph, __u32 maddr)
+{
+	struct ip_masq_mod *mmod;
+	struct ip_masq *ms = NULL;
+
+	for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
+		if (!mmod->mmod_in_create) continue;
+		if ((ms=mmod->mmod_in_create(skb, iph, maddr))) {
+			goto out;
+		}
+	}
+out:
+	return ms;
+}
+
+struct ip_masq * ip_masq_mod_out_create(const struct sk_buff *skb, const struct iphdr *iph,  __u32 maddr)
+{
+	struct ip_masq_mod *mmod;
+	struct ip_masq *ms = NULL;
+
+	for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
+		if (!mmod->mmod_out_create) continue;
+		if ((ms=mmod->mmod_out_create(skb, iph, maddr))) {
+			goto out;
+		}
+	}
+out:
+	return ms;
+}
+
+int ip_masq_mod_in_update(const struct sk_buff *skb, const struct iphdr *iph, struct ip_masq *ms)
+{
+	struct ip_masq_mod *mmod;
+	int ret = IP_MASQ_MOD_NOP;
+
+	for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
+		if (!mmod->mmod_in_update) continue;
+		switch (ret=mmod->mmod_in_update(skb, iph, ms)) {
+			case IP_MASQ_MOD_NOP:
+				continue;
+			case IP_MASQ_MOD_ACCEPT:
+			case IP_MASQ_MOD_REJECT:
+				goto out;
+		}
+	}
+out:
+	return ret;
+}
+
+int ip_masq_mod_out_update(const struct sk_buff *skb, const struct iphdr *iph, struct ip_masq *ms)
+{
+	struct ip_masq_mod *mmod;
+	int ret = IP_MASQ_MOD_NOP;
+
+	for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
+		if (!mmod->mmod_out_update) continue;
+		switch (ret=mmod->mmod_out_update(skb, iph, ms)) {
+			case IP_MASQ_MOD_NOP:
+				continue;
+			case IP_MASQ_MOD_ACCEPT:
+			case IP_MASQ_MOD_REJECT:
+				goto out;
+		}
+	}
+out:
+	return ret;
+}
+
+struct ip_masq_mod * ip_masq_mod_getbyname(const char *mmod_name)
+{
+	struct ip_masq_mod * mmod;
+
+	IP_MASQ_DEBUG(1, "searching mmod_name \"%s\"\n", mmod_name);
+	
+	for (mmod=ip_masq_mod_reg_base; mmod ; mmod=mmod->next_reg) {
+		if (mmod->mmod_ctl && *(mmod_name)
+				&& (strcmp(mmod_name, mmod->mmod_name)==0)) {
+			/* HIT */
+			return mmod;
+		}
+	}
+	return NULL;
+}
+
+/*
+ *	Module control entry
+ */
+int ip_masq_mod_ctl(int optname, struct ip_masq_ctl *mctl, int optlen)
+{
+	struct ip_masq_mod * mmod;
+#ifdef CONFIG_KMOD
+	char kmod_name[IP_MASQ_TNAME_MAX+8];
+#endif
+	/* tappo */
+	mctl->m_tname[IP_MASQ_TNAME_MAX-1] = 0;
+
+	mmod = ip_masq_mod_getbyname(mctl->m_tname);
+	if (mmod)
+		return mmod->mmod_ctl(optname, mctl, optlen);
+#ifdef CONFIG_KMOD
+	sprintf(kmod_name,"ip_masq_%s", mctl->m_tname);
+
+	IP_MASQ_DEBUG(1, "About to request \"%s\" module\n", kmod_name);
+
+	/* 
+	 *	Let sleep for a while ...
+	 */
+	request_module(kmod_name);
+	mmod = ip_masq_mod_getbyname(mctl->m_tname);
+	if (mmod)
+		return mmod->mmod_ctl(optname, mctl, optlen);
+#endif
+	return ESRCH;
+}