patch-1.3.81 linux/include/net/ip_masq.h

• Lines: 147
• Date: Sat Mar 30 14:03:16 1996
• Orig file: v1.3.80/linux/include/net/ip_masq.h
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.80/linux/include/net/ip_masq.h linux/include/net/ip_masq.h
@@ -0,0 +1,146 @@
+/*
+ * 	IP masquerading functionality definitions
+ */
+
+#ifndef _IP_MASQ_H
+#define _IP_MASQ_H
+
+#include <linux/types.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+
+/*
+ *	Linux ports don't normally get allocated above 32K.
+ *	I used an extra 4K port-space
+ */
+ 
+#define PORT_MASQ_BEGIN	60000
+#define PORT_MASQ_END	(PORT_MASQ_BEGIN+4096)
+
+#define MASQUERADE_EXPIRE_TCP     15*60*HZ
+#define MASQUERADE_EXPIRE_TCP_FIN  2*60*HZ
+#define MASQUERADE_EXPIRE_UDP      5*60*HZ
+
+#define IP_MASQ_F_OUT_SEQ              	0x01	/* must do output seq adjust */
+#define IP_MASQ_F_IN_SEQ              	0x02	/* must do input seq adjust */
+#define IP_MASQ_F_NO_DPORT    		0x04	/* no dport set yet */
+#define IP_MASQ_F_NO_DADDR      	0x08 	/* no daddr yet */
+#define IP_MASQ_F_HASHED		0x10 	/* hashed entry */
+#define IP_MASQ_F_SAW_FIN		0x20 	/* tcp fin pkt seen */
+
+#ifdef __KERNEL__
+
+/*
+ *	Delta seq. info structure
+ *	Each MASQ struct has 2 (output AND input seq. changes).
+ */
+
+struct ip_masq_seq {
+        __u32		init_seq;	/* Add delta from this seq */
+        short		delta;		/* Delta in sequence numbers */
+        short		previous_delta;	/* Delta in sequence numbers before last resized pkt */
+};
+
+/*
+ *	MASQ structure allocated for each masqueraded association
+ */
+struct ip_masq {
+        struct ip_masq  *m_link, *s_link; /* hashed link ptrs */
+	struct timer_list timer;	/* Expiration timer */
+	__u16 		protocol;	/* Which protocol are we talking? */
+	__u16		sport, dport, mport;	/* src, dst & masq ports */
+	__u32 		saddr, daddr, maddr;	/* src, dst & masq addresses */
+        struct ip_masq_seq out_seq, in_seq;
+	struct ip_masq_app *app;	/* bound ip_masq_app object */
+	unsigned  flags;        	/* status flags */
+};
+
+/*
+ *	[0]: UDP free_ports
+ *	[1]: TCP free_ports
+ */
+
+extern int ip_masq_free_ports[2];
+
+/*
+ *	ip_masq initializer (registers symbols and /proc/net entries)
+ */
+extern int ip_masq_init(void);
+
+/*
+ *	functions called from ip layer
+ */
+extern void ip_fw_masquerade(struct sk_buff **, struct device *);
+extern int ip_fw_demasquerade(struct sk_buff **, struct device *);
+
+/*
+ *	ip_masq obj creation/deletion functions.
+ */
+extern struct ip_masq *ip_masq_new(struct device *dev, int proto, __u32 saddr, __u16 sport, __u32 daddr, __u16 dport, unsigned flags);
+extern void ip_masq_set_expire(struct ip_masq *ms, unsigned long tout);
+
+
+/*
+ * 	
+ *	IP_MASQ_APP: IP application masquerading definitions 
+ *
+ */
+
+struct ip_masq_app
+{
+        struct ip_masq_app *next;
+        unsigned type;          /* type = proto<<16 | port (host byte order)*/
+        int n_attach;
+        int (*masq_init_1)      /* ip_masq initializer */
+                (struct ip_masq_app *, struct ip_masq *);
+        int (*masq_done_1)      /* ip_masq fin. */
+                (struct ip_masq_app *, struct ip_masq *);
+        int (*pkt_out)          /* output (masquerading) hook */
+                (struct ip_masq_app *, struct ip_masq *, struct sk_buff **, struct device *);
+        int (*pkt_in)           /* input (demasq) hook */
+                (struct ip_masq_app *, struct ip_masq *, struct sk_buff **, struct device *);
+};
+
+/*
+ *	ip_masq_app initializer
+ */
+extern int ip_masq_app_init(void);
+
+/*
+ * 	ip_masq_app object registration functions (port: host byte order)
+ */
+extern int register_ip_masq_app(struct ip_masq_app *mapp, unsigned short proto, __u16 port);
+extern int unregister_ip_masq_app(struct ip_masq_app *mapp);
+
+/*
+ *	get ip_masq_app obj by proto,port(net_byte_order)
+ */
+extern struct ip_masq_app * ip_masq_app_get(unsigned short proto, __u16 port);
+
+/*
+ *	ip_masq TO ip_masq_app (un)binding functions.
+ */
+extern struct ip_masq_app * ip_masq_bind_app(struct ip_masq *ms);
+extern int ip_masq_unbind_app(struct ip_masq *ms);
+
+/*
+ *	output and input app. masquerading hooks.
+ *	
+ */
+extern int ip_masq_app_pkt_out(struct ip_masq *, struct sk_buff **skb_p, struct device *dev);
+extern int ip_masq_app_pkt_in(struct ip_masq *, struct sk_buff **skb_p, struct device *dev);
+
+/*
+ *	/proc/net entry
+ */
+extern int ip_masq_app_getinfo(char *buffer, char **start, off_t offset, int length, int dummy);
+
+/*
+ *	skb_replace function used by "client" modules to replace
+ *	a segment of skb.
+ */
+extern struct sk_buff * ip_masq_skb_replace(struct sk_buff *skb, int pri, char *o_buf, int o_len, char *n_buf, int n_len);
+
+#endif /* __KERNEL__ */
+
+#endif /* _IP_MASQ_H */