1 /***************************************************************************
2 * nsock_proxy.h -- PRIVATE interface definitions for proxy handling. *
3 * *
4 ***********************IMPORTANT NSOCK LICENSE TERMS***********************
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53 ***************************************************************************/
54
55 /* $Id$ */
56
57 #ifndef NSOCK_PROXY_H
58 #define NSOCK_PROXY_H
59
60 #include "gh_list.h"
61
62 #if HAVE_NETDB_H
63 #include <netdb.h>
64 #endif
65
66 #include <nsock.h>
67 #include <errno.h>
68
69
70 /* ------------------- CONSTANTS ------------------- */
71 enum nsock_proxy_type {
72 PROXY_TYPE_HTTP = 0,
73 PROXY_TYPE_SOCKS4,
74 PROXY_TYPE_COUNT,
75 };
76
77 enum nsock_proxy_state {
78 /* Common initial state for all proxy types. */
79 PROXY_STATE_INITIAL,
80
81 /* HTTP proxy states. */
82 PROXY_STATE_HTTP_TCP_CONNECTED,
83 PROXY_STATE_HTTP_TUNNEL_ESTABLISHED,
84
85 /* SOCKS 4 proxy states. */
86 PROXY_STATE_SOCKS4_TCP_CONNECTED,
87 PROXY_STATE_SOCKS4_TUNNEL_ESTABLISHED,
88 };
89
90
91 /* ------------------- STRUCTURES ------------------- */
92
93 struct uri {
94 char *scheme;
95 char *user;
96 char *pass;
97 char *host;
98 char *path;
99 int port;
100 };
101
102 /* Static information about a proxy node in the chain. This is generated by
103 * parsing the proxy specification string given by user. Those structures are
104 * then read-only and stored in the nsock_pool. */
105 struct proxy_node {
106 const struct proxy_spec *spec;
107
108 struct sockaddr_storage ss;
109 size_t sslen;
110 unsigned short port;
111 char *nodestr; /* used for log messages */
112 gh_lnode_t nodeq;
113 };
114
115 /* Ordered list of proxy nodes, as specified in the proxy specification string. */
116 struct proxy_chain {
117 gh_list_t nodes;
118 };
119
120 /* IOD-specific context. For each IOD we establish a tunnel through the chain of
121 * proxies. This structure stores all the related information. */
122 struct proxy_chain_context {
123 const struct proxy_chain *px_chain;
124
125 /* Nodes iterator in px_chain->nodes */
126 struct proxy_node *px_current;
127
128 /* Current node connection state. */
129 enum nsock_proxy_state px_state;
130
131 /* Those fields are used to store information about the final target
132 * to reach. */
133 enum nse_type target_ev_type;
134 struct sockaddr_storage target_ss;
135 size_t target_sslen;
136 unsigned short target_port;
137 nsock_ev_handler target_handler;
138 };
139
140 struct proxy_op {
141 int (*node_new)(struct proxy_node **node, const struct uri *uri);
142 void (*node_delete)(struct proxy_node *node);
143 void (*handler)(nsock_pool nspool, nsock_event nsevent, void *udata);
144 };
145
146 struct proxy_spec {
147 const char *prefix;
148 enum nsock_proxy_type type;
149 const struct proxy_op *ops;
150 };
151
152
153 /* ------------------- UTIL FUNCTIONS ------------------- */
154 int proxy_resolve(const char *host, struct sockaddr *addr, size_t *addrlen);
155
proxy_ctx_node_next(struct proxy_chain_context * ctx)156 static inline struct proxy_node *proxy_ctx_node_next(struct proxy_chain_context *ctx) {
157 gh_lnode_t *next;
158
159 assert(ctx);
160 assert(ctx->px_current);
161
162 next = gh_lnode_next(&ctx->px_current->nodeq);
163 if (!next)
164 return NULL;
165
166 return container_of(next, struct proxy_node, nodeq);
167 }
168
169
170 /* ------------------- PROTOTYPES ------------------- */
171
172 struct proxy_chain_context *proxy_chain_context_new(nsock_pool nspool);
173 void proxy_chain_context_delete(struct proxy_chain_context *ctx);
174
175 void nsock_proxy_ev_dispatch(nsock_pool nspool, nsock_event nsevent, void *udata);
176 void forward_event(nsock_pool nspool, nsock_event nse, void *udata);
177
178
179 #endif /* NSOCK_PROXY_H */
180
181