1 /*
2  * Copyright 2001-2007 Niels Provos <provos@citi.umich.edu>
3  * Copyright 2007-2012 Niels Provos and Nick Mathewson
4  *
5  * This header file contains definitions for dealing with HTTP requests
6  * that are internal to libevent.  As user of the library, you should not
7  * need to know about these.
8  */
9 
10 #ifndef HTTP_INTERNAL_H_INCLUDED_
11 #define HTTP_INTERNAL_H_INCLUDED_
12 
13 #include "event2/event_struct.h"
14 #include "util-internal.h"
15 #include "defer-internal.h"
16 
17 #define HTTP_CONNECT_TIMEOUT	45
18 #define HTTP_WRITE_TIMEOUT	50
19 #define HTTP_READ_TIMEOUT	50
20 
21 enum message_read_status {
22 	ALL_DATA_READ = 1,
23 	MORE_DATA_EXPECTED = 0,
24 	DATA_CORRUPTED = -1,
25 	REQUEST_CANCELED = -2,
26 	DATA_TOO_LONG = -3
27 };
28 
29 struct evbuffer;
30 struct addrinfo;
31 struct evhttp_request;
32 
33 /* Indicates an unknown request method. */
34 #define EVHTTP_REQ_UNKNOWN_ (1<<15)
35 
36 enum evhttp_connection_state {
37 	EVCON_DISCONNECTED,	/**< not currently connected not trying either*/
38 	EVCON_CONNECTING,	/**< tries to currently connect */
39 	EVCON_IDLE,		/**< connection is established */
40 	EVCON_READING_FIRSTLINE,/**< reading Request-Line (incoming conn) or
41 				 **< Status-Line (outgoing conn) */
42 	EVCON_READING_HEADERS,	/**< reading request/response headers */
43 	EVCON_READING_BODY,	/**< reading request/response body */
44 	EVCON_READING_TRAILER,	/**< reading request/response chunked trailer */
45 	EVCON_WRITING		/**< writing request/response headers/body */
46 };
47 
48 struct event_base;
49 
50 /* A client or server connection. */
51 struct evhttp_connection {
52 	/* we use this tailq only if this connection was created for an http
53 	 * server */
54 	TAILQ_ENTRY(evhttp_connection) next;
55 
56 	evutil_socket_t fd;
57 	struct bufferevent *bufev;
58 
59 	struct event retry_ev;		/* for retrying connects */
60 
61 	char *bind_address;		/* address to use for binding the src */
62 	ev_uint16_t bind_port;		/* local port for binding the src */
63 
64 	char *address;			/* address to connect to */
65 	ev_uint16_t port;
66 
67 	size_t max_headers_size;
68 	ev_uint64_t max_body_size;
69 
70 	int flags;
71 #define EVHTTP_CON_INCOMING	0x0001       /* only one request on it ever */
72 #define EVHTTP_CON_OUTGOING	0x0002       /* multiple requests possible */
73 #define EVHTTP_CON_CLOSEDETECT	0x0004   /* detecting if persistent close */
74 /* set when we want to auto free the connection */
75 #define EVHTTP_CON_AUTOFREE	EVHTTP_CON_PUBLIC_FLAGS_END
76 /* Installed when attempt to read HTTP error after write failed, see
77  * EVHTTP_CON_READ_ON_WRITE_ERROR */
78 #define EVHTTP_CON_READING_ERROR	(EVHTTP_CON_AUTOFREE << 1)
79 
80 	struct timeval timeout;		/* timeout for events */
81 	int retry_cnt;			/* retry count */
82 	int retry_max;			/* maximum number of retries */
83 	struct timeval initial_retry_timeout; /* Timeout for low long to wait
84 					       * after first failing attempt
85 					       * before retry */
86 
87 	enum evhttp_connection_state state;
88 
89 	/* for server connections, the http server they are connected with */
90 	struct evhttp *http_server;
91 
92 	TAILQ_HEAD(evcon_requestq, evhttp_request) requests;
93 
94 	void (*cb)(struct evhttp_connection *, void *);
95 	void *cb_arg;
96 
97 	void (*closecb)(struct evhttp_connection *, void *);
98 	void *closecb_arg;
99 
100 	struct event_callback read_more_deferred_cb;
101 
102 	struct event_base *base;
103 	struct evdns_base *dns_base;
104 	int ai_family;
105 };
106 
107 /* A callback for an http server */
108 struct evhttp_cb {
109 	TAILQ_ENTRY(evhttp_cb) next;
110 
111 	char *what;
112 
113 	void (*cb)(struct evhttp_request *req, void *);
114 	void *cbarg;
115 };
116 
117 /* both the http server as well as the rpc system need to queue connections */
118 TAILQ_HEAD(evconq, evhttp_connection);
119 
120 /* each bound socket is stored in one of these */
121 struct evhttp_bound_socket {
122 	TAILQ_ENTRY(evhttp_bound_socket) next;
123 
124 	struct evconnlistener *listener;
125 };
126 
127 /* server alias list item. */
128 struct evhttp_server_alias {
129 	TAILQ_ENTRY(evhttp_server_alias) next;
130 
131 	char *alias; /* the server alias. */
132 };
133 
134 struct evhttp {
135 	/* Next vhost, if this is a vhost. */
136 	TAILQ_ENTRY(evhttp) next_vhost;
137 
138 	/* All listeners for this host */
139 	TAILQ_HEAD(boundq, evhttp_bound_socket) sockets;
140 
141 	TAILQ_HEAD(httpcbq, evhttp_cb) callbacks;
142 
143 	/* All live connections on this host. */
144 	struct evconq connections;
145 
146 	TAILQ_HEAD(vhostsq, evhttp) virtualhosts;
147 
148 	TAILQ_HEAD(aliasq, evhttp_server_alias) aliases;
149 
150 	/* NULL if this server is not a vhost */
151 	char *vhost_pattern;
152 
153 	struct timeval timeout;
154 
155 	size_t default_max_headers_size;
156 	ev_uint64_t default_max_body_size;
157 	int flags;
158 	const char *default_content_type;
159 
160 	/* Bitmask of all HTTP methods that we accept and pass to user
161 	 * callbacks. */
162 	ev_uint16_t allowed_methods;
163 
164 	/* Fallback callback if all the other callbacks for this connection
165 	   don't match. */
166 	void (*gencb)(struct evhttp_request *req, void *);
167 	void *gencbarg;
168 	struct bufferevent* (*bevcb)(struct event_base *, void *);
169 	void *bevcbarg;
170 
171 	struct event_base *base;
172 };
173 
174 /* XXX most of these functions could be static. */
175 
176 /* resets the connection; can be reused for more requests */
177 void evhttp_connection_reset_(struct evhttp_connection *);
178 
179 /* connects if necessary */
180 int evhttp_connection_connect_(struct evhttp_connection *);
181 
182 enum evhttp_request_error;
183 /* notifies the current request that it failed; resets connection */
184 EVENT2_EXPORT_SYMBOL
185 void evhttp_connection_fail_(struct evhttp_connection *,
186     enum evhttp_request_error error);
187 
188 enum message_read_status;
189 
190 EVENT2_EXPORT_SYMBOL
191 enum message_read_status evhttp_parse_firstline_(struct evhttp_request *, struct evbuffer*);
192 EVENT2_EXPORT_SYMBOL
193 enum message_read_status evhttp_parse_headers_(struct evhttp_request *, struct evbuffer*);
194 
195 void evhttp_start_read_(struct evhttp_connection *);
196 void evhttp_start_write_(struct evhttp_connection *);
197 
198 /* response sending HTML the data in the buffer */
199 void evhttp_response_code_(struct evhttp_request *, int, const char *);
200 void evhttp_send_page_(struct evhttp_request *, struct evbuffer *);
201 
202 EVENT2_EXPORT_SYMBOL
203 int evhttp_decode_uri_internal(const char *uri, size_t length,
204     char *ret, int decode_plus);
205 
206 #endif /* HTTP_INTERNAL_H_INCLUDED_ */
207