include/linux/netfilter/nf_conntrack_sip.h

#ifndef __NF_CONNTRACK_SIP_H__
#define __NF_CONNTRACK_SIP_H__
#ifdef __KERNEL__

#define SIP_PORT	5060
#define SIP_TIMEOUT	3600

struct sip_handler {
	const char	*method;
	unsigned int	len;
	int		(*request)(struct sk_buff *skb,
				   const char **dptr, unsigned int *datalen,
				   unsigned int cseq);
	int		(*response)(struct sk_buff *skb,
				    const char **dptr, unsigned int *datalen,
				    unsigned int cseq, unsigned int code);
};

#define SIP_HANDLER(__method, __request, __response)			\
{									\
	.method		= (__method),					\
	.len		= sizeof(__method) - 1,				\
	.request	= (__request),					\
	.response	= (__response),					\
}

struct sip_header {
	const char	*name;
	const char	*cname;
	const char	*search;
	unsigned int	len;
	unsigned int	clen;
	unsigned int	slen;
	int		(*match_len)(const struct nf_conn *ct,
				     const char *dptr, const char *limit,
				     int *shift);
};

#define __SIP_HDR(__name, __cname, __search, __match)			\
{									\
	.name		= (__name),					\
	.len		= sizeof(__name) - 1,				\
	.cname		= (__cname),					\
	.clen		= (__cname) ? sizeof(__cname) - 1 : 0,		\
	.search		= (__search),					\
	.slen		= (__search) ? sizeof(__search) - 1 : 0,	\
	.match_len	= (__match),					\
}

#define SIP_HDR(__name, __cname, __search, __match) \
	__SIP_HDR(__name, __cname, __search, __match)

#define SDP_HDR(__name, __search, __match) \
	__SIP_HDR(__name, NULL, __search, __match)

enum sip_header_types {
	SIP_HDR_CSEQ,
	SIP_HDR_FROM,
	SIP_HDR_TO,
	SIP_HDR_CONTACT,
	SIP_HDR_VIA,
	SIP_HDR_CONTENT_LENGTH,
};

enum sdp_header_types {
	SDP_HDR_UNSPEC,
	SDP_HDR_VERSION,
	SDP_HDR_OWNER_IP4,
	SDP_HDR_CONNECTION_IP4,
	SDP_HDR_OWNER_IP6,
	SDP_HDR_CONNECTION_IP6,
	SDP_HDR_MEDIA,
};

extern unsigned int (*nf_nat_sip_hook)(struct sk_buff *skb,
				       const char **dptr,
				       unsigned int *datalen);
extern unsigned int (*nf_nat_sdp_hook)(struct sk_buff *skb,
				       const char **dptr,
				       unsigned int *datalen,
				       struct nf_conntrack_expect *exp);

extern int ct_sip_parse_request(const struct nf_conn *ct,
				const char *dptr, unsigned int datalen,
				unsigned int *matchoff, unsigned int *matchlen,
				union nf_inet_addr *addr, __be16 *port);
extern int ct_sip_get_header(const struct nf_conn *ct, const char *dptr,
			     unsigned int dataoff, unsigned int datalen,
			     enum sip_header_types type,
			     unsigned int *matchoff, unsigned int *matchlen);
extern int ct_sip_parse_header_uri(const struct nf_conn *ct, const char *dptr,
				   unsigned int *dataoff, unsigned int datalen,
				   enum sip_header_types type, int *in_header,
				   unsigned int *matchoff, unsigned int *matchlen,
				   union nf_inet_addr *addr, __be16 *port);

extern int ct_sip_get_sdp_header(const struct nf_conn *ct, const char *dptr,
				 unsigned int dataoff, unsigned int datalen,
				 enum sdp_header_types type,
				 enum sdp_header_types term,
				 unsigned int *matchoff, unsigned int *matchlen);

#endif /* __KERNEL__ */
#endif /* __NF_CONNTRACK_SIP_H__ */