1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		Definitions for inet_sock
7  *
8  * Authors:	Many, reorganised here by
9  * 		Arnaldo Carvalho de Melo <acme@mandriva.com>
10  *
11  *		This program is free software; you can redistribute it and/or
12  *		modify it under the terms of the GNU General Public License
13  *		as published by the Free Software Foundation; either version
14  *		2 of the License, or (at your option) any later version.
15  */
16 #ifndef _INET_SOCK_H
17 #define _INET_SOCK_H
18 
19 
20 #include <linux/kmemcheck.h>
21 #include <linux/string.h>
22 #include <linux/types.h>
23 #include <linux/jhash.h>
24 #include <linux/netdevice.h>
25 
26 #include <net/flow.h>
27 #include <net/sock.h>
28 #include <net/request_sock.h>
29 #include <net/netns/hash.h>
30 
31 /** struct ip_options - IP Options
32  *
33  * @faddr - Saved first hop address
34  * @is_data - Options in __data, rather than skb
35  * @is_strictroute - Strict source route
36  * @srr_is_hit - Packet destination addr was our one
37  * @is_changed - IP checksum more not valid
38  * @rr_needaddr - Need to record addr of outgoing dev
39  * @ts_needtime - Need to record timestamp
40  * @ts_needaddr - Need to record addr of outgoing dev
41  */
42 struct ip_options {
43 	__be32		faddr;
44 	unsigned char	optlen;
45 	unsigned char	srr;
46 	unsigned char	rr;
47 	unsigned char	ts;
48 	unsigned char	is_strictroute:1,
49 			srr_is_hit:1,
50 			is_changed:1,
51 			rr_needaddr:1,
52 			ts_needtime:1,
53 			ts_needaddr:1;
54 	unsigned char	router_alert;
55 	unsigned char	cipso;
56 	unsigned char	__pad2;
57 	unsigned char	__data[0];
58 };
59 
60 #define optlength(opt) (sizeof(struct ip_options) + opt->optlen)
61 
62 struct inet_request_sock {
63 	struct request_sock	req;
64 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
65 	u16			inet6_rsk_offset;
66 #endif
67 	__be16			loc_port;
68 	__be32			loc_addr;
69 	__be32			rmt_addr;
70 	__be16			rmt_port;
71 	kmemcheck_bitfield_begin(flags);
72 	u16			snd_wscale : 4,
73 				rcv_wscale : 4,
74 				tstamp_ok  : 1,
75 				sack_ok	   : 1,
76 				wscale_ok  : 1,
77 				ecn_ok	   : 1,
78 				acked	   : 1,
79 				no_srccheck: 1;
80 	kmemcheck_bitfield_end(flags);
81 	struct ip_options	*opt;
82 };
83 
inet_rsk(const struct request_sock * sk)84 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
85 {
86 	return (struct inet_request_sock *)sk;
87 }
88 
89 struct inet_cork {
90 	unsigned int		flags;
91 	unsigned int		fragsize;
92 	struct ip_options	*opt;
93 	struct dst_entry	*dst;
94 	int			length; /* Total length of all frames */
95 	__be32			addr;
96 	struct flowi		fl;
97 	struct page		*page;
98 	u32			off;
99 	u8			tx_flags;
100 };
101 
102 struct ip_mc_socklist;
103 struct ipv6_pinfo;
104 struct rtable;
105 
106 /** struct inet_sock - representation of INET sockets
107  *
108  * @sk - ancestor class
109  * @pinet6 - pointer to IPv6 control block
110  * @inet_daddr - Foreign IPv4 addr
111  * @inet_rcv_saddr - Bound local IPv4 addr
112  * @inet_dport - Destination port
113  * @inet_num - Local port
114  * @inet_saddr - Sending source
115  * @uc_ttl - Unicast TTL
116  * @inet_sport - Source port
117  * @inet_id - ID counter for DF pkts
118  * @tos - TOS
119  * @mc_ttl - Multicasting TTL
120  * @is_icsk - is this an inet_connection_sock?
121  * @mc_index - Multicast device index
122  * @mc_list - Group array
123  * @cork - info to build ip hdr on each ip frag while socket is corked
124  */
125 struct inet_sock {
126 	/* sk and pinet6 has to be the first two members of inet_sock */
127 	struct sock		sk;
128 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
129 	struct ipv6_pinfo	*pinet6;
130 #endif
131 	/* Socket demultiplex comparisons on incoming packets. */
132 #define inet_daddr		sk.__sk_common.skc_daddr
133 #define inet_rcv_saddr		sk.__sk_common.skc_rcv_saddr
134 
135 	__be16			inet_dport;
136 	__u16			inet_num;
137 	__be32			inet_saddr;
138 	__s16			uc_ttl;
139 	__u16			cmsg_flags;
140 	__be16			inet_sport;
141 	__u16			inet_id;
142 
143 	struct ip_options	*opt;
144 	__u8			tos;
145 	__u8			min_ttl;
146 	__u8			mc_ttl;
147 	__u8			pmtudisc;
148 	__u8			recverr:1,
149 				is_icsk:1,
150 				freebind:1,
151 				hdrincl:1,
152 				mc_loop:1,
153 				transparent:1,
154 				mc_all:1,
155 				nodefrag:1;
156 	int			mc_index;
157 	__be32			mc_addr;
158 	struct ip_mc_socklist __rcu	*mc_list;
159 	struct inet_cork	cork;
160 };
161 
162 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
163 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
164 
inet_sk(const struct sock * sk)165 static inline struct inet_sock *inet_sk(const struct sock *sk)
166 {
167 	return (struct inet_sock *)sk;
168 }
169 
__inet_sk_copy_descendant(struct sock * sk_to,const struct sock * sk_from,const int ancestor_size)170 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
171 					     const struct sock *sk_from,
172 					     const int ancestor_size)
173 {
174 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
175 	       sk_from->sk_prot->obj_size - ancestor_size);
176 }
177 #if !(defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE))
inet_sk_copy_descendant(struct sock * sk_to,const struct sock * sk_from)178 static inline void inet_sk_copy_descendant(struct sock *sk_to,
179 					   const struct sock *sk_from)
180 {
181 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
182 }
183 #endif
184 
185 extern int inet_sk_rebuild_header(struct sock *sk);
186 
187 extern u32 inet_ehash_secret;
188 extern void build_ehash_secret(void);
189 
inet_ehashfn(struct net * net,const __be32 laddr,const __u16 lport,const __be32 faddr,const __be16 fport)190 static inline unsigned int inet_ehashfn(struct net *net,
191 					const __be32 laddr, const __u16 lport,
192 					const __be32 faddr, const __be16 fport)
193 {
194 	return jhash_3words((__force __u32) laddr,
195 			    (__force __u32) faddr,
196 			    ((__u32) lport) << 16 | (__force __u32)fport,
197 			    inet_ehash_secret + net_hash_mix(net));
198 }
199 
inet_sk_ehashfn(const struct sock * sk)200 static inline int inet_sk_ehashfn(const struct sock *sk)
201 {
202 	const struct inet_sock *inet = inet_sk(sk);
203 	const __be32 laddr = inet->inet_rcv_saddr;
204 	const __u16 lport = inet->inet_num;
205 	const __be32 faddr = inet->inet_daddr;
206 	const __be16 fport = inet->inet_dport;
207 	struct net *net = sock_net(sk);
208 
209 	return inet_ehashfn(net, laddr, lport, faddr, fport);
210 }
211 
inet_reqsk_alloc(struct request_sock_ops * ops)212 static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops)
213 {
214 	struct request_sock *req = reqsk_alloc(ops);
215 	struct inet_request_sock *ireq = inet_rsk(req);
216 
217 	if (req != NULL) {
218 		kmemcheck_annotate_bitfield(ireq, flags);
219 		ireq->opt = NULL;
220 	}
221 
222 	return req;
223 }
224 
inet_sk_flowi_flags(const struct sock * sk)225 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
226 {
227 	__u8 flags = 0;
228 
229 	if (inet_sk(sk)->transparent)
230 		flags |= FLOWI_FLAG_ANYSRC;
231 	if (sk->sk_protocol == IPPROTO_TCP)
232 		flags |= FLOWI_FLAG_PRECOW_METRICS;
233 	return flags;
234 }
235 
236 #endif	/* _INET_SOCK_H */
237