1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __NF_CONNTRACK_SIP_H__
3#define __NF_CONNTRACK_SIP_H__
4
5#include <linux/skbuff.h>
6#include <linux/types.h>
7#include <net/netfilter/nf_conntrack_expect.h>
8
9#define SIP_PORT	5060
10#define SIP_TIMEOUT	3600
11
12struct nf_ct_sip_master {
13	unsigned int	register_cseq;
14	unsigned int	invite_cseq;
15	__be16		forced_dport;
16};
17
18enum sip_expectation_classes {
19	SIP_EXPECT_SIGNALLING,
20	SIP_EXPECT_AUDIO,
21	SIP_EXPECT_VIDEO,
22	SIP_EXPECT_IMAGE,
23	__SIP_EXPECT_MAX
24};
25#define SIP_EXPECT_MAX	(__SIP_EXPECT_MAX - 1)
26
27struct sdp_media_type {
28	const char			*name;
29	unsigned int			len;
30	enum sip_expectation_classes	class;
31};
32
33#define SDP_MEDIA_TYPE(__name, __class)					\
34{									\
35	.name	= (__name),						\
36	.len	= sizeof(__name) - 1,					\
37	.class	= (__class),						\
38}
39
40struct sip_handler {
41	const char	*method;
42	unsigned int	len;
43	int		(*request)(struct sk_buff *skb, unsigned int protoff,
44				   unsigned int dataoff,
45				   const char **dptr, unsigned int *datalen,
46				   unsigned int cseq);
47	int		(*response)(struct sk_buff *skb, unsigned int protoff,
48				    unsigned int dataoff,
49				    const char **dptr, unsigned int *datalen,
50				    unsigned int cseq, unsigned int code);
51};
52
53#define SIP_HANDLER(__method, __request, __response)			\
54{									\
55	.method		= (__method),					\
56	.len		= sizeof(__method) - 1,				\
57	.request	= (__request),					\
58	.response	= (__response),					\
59}
60
61struct sip_header {
62	const char	*name;
63	const char	*cname;
64	const char	*search;
65	unsigned int	len;
66	unsigned int	clen;
67	unsigned int	slen;
68	int		(*match_len)(const struct nf_conn *ct,
69				     const char *dptr, const char *limit,
70				     int *shift);
71};
72
73#define __SIP_HDR(__name, __cname, __search, __match)			\
74{									\
75	.name		= (__name),					\
76	.len		= sizeof(__name) - 1,				\
77	.cname		= (__cname),					\
78	.clen		= (__cname) ? sizeof(__cname) - 1 : 0,		\
79	.search		= (__search),					\
80	.slen		= (__search) ? sizeof(__search) - 1 : 0,	\
81	.match_len	= (__match),					\
82}
83
84#define SIP_HDR(__name, __cname, __search, __match) \
85	__SIP_HDR(__name, __cname, __search, __match)
86
87#define SDP_HDR(__name, __search, __match) \
88	__SIP_HDR(__name, NULL, __search, __match)
89
90enum sip_header_types {
91	SIP_HDR_CSEQ,
92	SIP_HDR_FROM,
93	SIP_HDR_TO,
94	SIP_HDR_CONTACT,
95	SIP_HDR_VIA_UDP,
96	SIP_HDR_VIA_TCP,
97	SIP_HDR_EXPIRES,
98	SIP_HDR_CONTENT_LENGTH,
99	SIP_HDR_CALL_ID,
100};
101
102enum sdp_header_types {
103	SDP_HDR_UNSPEC,
104	SDP_HDR_VERSION,
105	SDP_HDR_OWNER,
106	SDP_HDR_CONNECTION,
107	SDP_HDR_MEDIA,
108};
109
110struct nf_nat_sip_hooks {
111	unsigned int (*msg)(struct sk_buff *skb,
112			    unsigned int protoff,
113			    unsigned int dataoff,
114			    const char **dptr,
115			    unsigned int *datalen);
116
117	void (*seq_adjust)(struct sk_buff *skb,
118			   unsigned int protoff, s16 off);
119
120	unsigned int (*expect)(struct sk_buff *skb,
121			       unsigned int protoff,
122			       unsigned int dataoff,
123			       const char **dptr,
124			       unsigned int *datalen,
125			       struct nf_conntrack_expect *exp,
126			       unsigned int matchoff,
127			       unsigned int matchlen);
128
129	unsigned int (*sdp_addr)(struct sk_buff *skb,
130				 unsigned int protoff,
131				 unsigned int dataoff,
132				 const char **dptr,
133				 unsigned int *datalen,
134				 unsigned int sdpoff,
135				 enum sdp_header_types type,
136				 enum sdp_header_types term,
137				 const union nf_inet_addr *addr);
138
139	unsigned int (*sdp_port)(struct sk_buff *skb,
140				 unsigned int protoff,
141				 unsigned int dataoff,
142				 const char **dptr,
143				 unsigned int *datalen,
144				 unsigned int matchoff,
145				 unsigned int matchlen,
146				 u_int16_t port);
147
148	unsigned int (*sdp_session)(struct sk_buff *skb,
149				    unsigned int protoff,
150				    unsigned int dataoff,
151				    const char **dptr,
152				    unsigned int *datalen,
153				    unsigned int sdpoff,
154				    const union nf_inet_addr *addr);
155
156	unsigned int (*sdp_media)(struct sk_buff *skb,
157				  unsigned int protoff,
158				  unsigned int dataoff,
159				  const char **dptr,
160				  unsigned int *datalen,
161				  struct nf_conntrack_expect *rtp_exp,
162				  struct nf_conntrack_expect *rtcp_exp,
163				  unsigned int mediaoff,
164				  unsigned int medialen,
165				  union nf_inet_addr *rtp_addr);
166};
167extern const struct nf_nat_sip_hooks __rcu *nf_nat_sip_hooks;
168
169int ct_sip_parse_request(const struct nf_conn *ct, const char *dptr,
170			 unsigned int datalen, unsigned int *matchoff,
171			 unsigned int *matchlen, union nf_inet_addr *addr,
172			 __be16 *port);
173int ct_sip_get_header(const struct nf_conn *ct, const char *dptr,
174		      unsigned int dataoff, unsigned int datalen,
175		      enum sip_header_types type, unsigned int *matchoff,
176		      unsigned int *matchlen);
177int ct_sip_parse_header_uri(const struct nf_conn *ct, const char *dptr,
178			    unsigned int *dataoff, unsigned int datalen,
179			    enum sip_header_types type, int *in_header,
180			    unsigned int *matchoff, unsigned int *matchlen,
181			    union nf_inet_addr *addr, __be16 *port);
182int ct_sip_parse_address_param(const struct nf_conn *ct, const char *dptr,
183			       unsigned int dataoff, unsigned int datalen,
184			       const char *name, unsigned int *matchoff,
185			       unsigned int *matchlen, union nf_inet_addr *addr,
186			       bool delim);
187int ct_sip_parse_numerical_param(const struct nf_conn *ct, const char *dptr,
188				 unsigned int off, unsigned int datalen,
189				 const char *name, unsigned int *matchoff,
190				 unsigned int *matchen, unsigned int *val);
191
192int ct_sip_get_sdp_header(const struct nf_conn *ct, const char *dptr,
193			  unsigned int dataoff, unsigned int datalen,
194			  enum sdp_header_types type,
195			  enum sdp_header_types term,
196			  unsigned int *matchoff, unsigned int *matchlen);
197
198#endif /* __NF_CONNTRACK_SIP_H__ */
199