Tor  0.4.7.0-alpha-dev
connection.h
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1 /* Copyright (c) 2001 Matej Pfajfar.
2  * Copyright (c) 2001-2004, Roger Dingledine.
3  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
4  * Copyright (c) 2007-2021, The Tor Project, Inc. */
5 /* See LICENSE for licensing information */
6 
7 /**
8  * \file connection.h
9  * \brief Header file for connection.c.
10  **/
11 
12 #ifndef TOR_CONNECTION_H
13 #define TOR_CONNECTION_H
14 
16 #include "lib/log/log.h"
17 
18 #ifdef HAVE_SYS_SOCKET_H
19 #include <sys/socket.h>
20 #endif
21 
23 struct connection_t;
24 struct dir_connection_t;
25 struct or_connection_t;
26 struct edge_connection_t;
27 struct entry_connection_t;
29 struct port_cfg_t;
30 struct tor_addr_t;
31 struct or_options_t;
32 
35  const struct connection_t *);
36 
37 struct buf_t;
38 
39 #define CONN_TYPE_MIN_ 3
40 /** Type for sockets listening for OR connections. */
41 #define CONN_TYPE_OR_LISTENER 3
42 /** A bidirectional TLS connection transmitting a sequence of cells.
43  * May be from an OR to an OR, or from an OP to an OR. */
44 #define CONN_TYPE_OR 4
45 /** A TCP connection from an onion router to a stream's destination. */
46 #define CONN_TYPE_EXIT 5
47 /** Type for sockets listening for SOCKS connections. */
48 #define CONN_TYPE_AP_LISTENER 6
49 /** A SOCKS proxy connection from the user application to the onion
50  * proxy. */
51 #define CONN_TYPE_AP 7
52 /** Type for sockets listening for HTTP connections to the directory server. */
53 #define CONN_TYPE_DIR_LISTENER 8
54 /** Type for HTTP connections to the directory server. */
55 #define CONN_TYPE_DIR 9
56 /* Type 10 is unused. */
57 /** Type for listening for connections from user interface process. */
58 #define CONN_TYPE_CONTROL_LISTENER 11
59 /** Type for connections from user interface process. */
60 #define CONN_TYPE_CONTROL 12
61 /** Type for sockets listening for transparent connections redirected by pf or
62  * netfilter. */
63 #define CONN_TYPE_AP_TRANS_LISTENER 13
64 /** Type for sockets listening for transparent connections redirected by
65  * natd. */
66 #define CONN_TYPE_AP_NATD_LISTENER 14
67 /** Type for sockets listening for DNS requests. */
68 #define CONN_TYPE_AP_DNS_LISTENER 15
69 
70 /** Type for connections from the Extended ORPort. */
71 #define CONN_TYPE_EXT_OR 16
72 /** Type for sockets listening for Extended ORPort connections. */
73 #define CONN_TYPE_EXT_OR_LISTENER 17
74 /** Type for sockets listening for HTTP CONNECT tunnel connections. */
75 #define CONN_TYPE_AP_HTTP_CONNECT_LISTENER 18
76 /** Type for sockets listening for Metrics query connections. */
77 #define CONN_TYPE_METRICS_LISTENER 19
78 /** Type for connections from metrics listener. */
79 #define CONN_TYPE_METRICS 20
80 
81 #define CONN_TYPE_MAX_ 21
82 /* !!!! If _CONN_TYPE_MAX is ever over 31, we must grow the type field in
83  * struct connection_t. */
84 
85 /* Proxy client handshake states */
86 /* We use a proxy but we haven't even connected to it yet. */
87 #define PROXY_INFANT 1
88 /* We use an HTTP proxy and we've sent the CONNECT command. */
89 #define PROXY_HTTPS_WANT_CONNECT_OK 2
90 /* We use a SOCKS4 proxy and we've sent the CONNECT command. */
91 #define PROXY_SOCKS4_WANT_CONNECT_OK 3
92 /* We use a SOCKS5 proxy and we try to negotiate without
93  any authentication . */
94 #define PROXY_SOCKS5_WANT_AUTH_METHOD_NONE 4
95 /* We use a SOCKS5 proxy and we try to negotiate with
96  Username/Password authentication . */
97 #define PROXY_SOCKS5_WANT_AUTH_METHOD_RFC1929 5
98 /* We use a SOCKS5 proxy and we just sent our credentials. */
99 #define PROXY_SOCKS5_WANT_AUTH_RFC1929_OK 6
100 /* We use a SOCKS5 proxy and we just sent our CONNECT command. */
101 #define PROXY_SOCKS5_WANT_CONNECT_OK 7
102 /* We use an HAPROXY proxy and we just sent the proxy header. */
103 #define PROXY_HAPROXY_WAIT_FOR_FLUSH 8
104 /* We use a proxy and we CONNECTed successfully!. */
105 #define PROXY_CONNECTED 9
106 
107 /** State for any listener connection. */
108 #define LISTENER_STATE_READY 0
109 
110 /**
111  * This struct associates an old listener connection to be replaced
112  * by new connection described by port configuration. Only used when
113  * moving listeners to/from wildcard IP address.
114  */
115 typedef struct
116 {
117  struct connection_t *old_conn; /* Old listener connection to be replaced */
118  const struct port_cfg_t *new_port; /* New port configuration */
120 
121 const char *conn_type_to_string(int type);
122 const char *conn_state_to_string(int type, int state);
124 
125 const char *connection_describe(const connection_t *conn);
126 const char *connection_describe_peer(const connection_t *conn);
127 
128 struct dir_connection_t *dir_connection_new(int socket_family);
129 struct or_connection_t *or_connection_new(int type, int socket_family);
130 struct edge_connection_t *edge_connection_new(int type, int socket_family);
131 struct entry_connection_t *entry_connection_new(int type, int socket_family);
132 struct control_connection_t *control_connection_new(int socket_family);
134  int socket_family);
137  const struct listener_connection_t *listener);
138 void connection_link_connections(struct connection_t *conn_a,
139  struct connection_t *conn_b);
140 MOCK_DECL(void,connection_free_,(struct connection_t *conn));
141 #define connection_free(conn) \
142  FREE_AND_NULL(struct connection_t, connection_free_, (conn))
143 void connection_free_all(void);
145 void connection_close_immediate(struct connection_t *conn);
146 void connection_mark_for_close_(struct connection_t *conn,
147  int line, const char *file);
149  (struct connection_t *conn, int line, const char *file));
150 
151 #define connection_mark_for_close(c) \
152  connection_mark_for_close_((c), __LINE__, SHORT_FILE__)
153 #define connection_mark_for_close_internal(c) \
154  connection_mark_for_close_internal_((c), __LINE__, SHORT_FILE__)
155 
156 /**
157  * Mark 'c' for close, but try to hold it open until all the data is written.
158  * Use the _internal versions of connection_mark_for_close; this should be
159  * called when you either are sure that if this is an or_connection_t the
160  * controlling channel has been notified (e.g. with
161  * connection_or_notify_error()), or you actually are the
162  * connection_or_close_for_error() or connection_or_close_normally function.
163  * For all other cases, use connection_mark_and_flush() instead, which
164  * checks for struct or_connection_t properly, instead. See below.
165  */
166 #define connection_mark_and_flush_internal_(c,line,file) \
167  do { \
168  struct connection_t *tmp_conn__ = (c); \
169  connection_mark_for_close_internal_(tmp_conn__, (line), (file)); \
170  tmp_conn__->hold_open_until_flushed = 1; \
171  } while (0)
172 
173 #define connection_mark_and_flush_internal(c) \
174  connection_mark_and_flush_internal_((c), __LINE__, SHORT_FILE__)
175 
176 /**
177  * Mark 'c' for close, but try to hold it open until all the data is written.
178  */
179 #define connection_mark_and_flush_(c,line,file) \
180  do { \
181  struct connection_t *tmp_conn_ = (c); \
182  if (tmp_conn_->type == CONN_TYPE_OR) { \
183  log_warn(LD_CHANNEL | LD_BUG, \
184  "Something tried to close (and flush) an or_connection_t" \
185  " without going through channels at %s:%d", \
186  file, line); \
187  connection_or_close_for_error(TO_OR_CONN(tmp_conn_), 1); \
188  } else { \
189  connection_mark_and_flush_internal_(c, line, file); \
190  } \
191  } while (0)
192 
193 #define connection_mark_and_flush(c) \
194  connection_mark_and_flush_((c), __LINE__, SHORT_FILE__)
195 
196 void connection_expire_held_open(void);
197 
198 int connection_connect(struct connection_t *conn, const char *address,
199  const struct tor_addr_t *addr,
200  uint16_t port, int *socket_error);
201 
202 #ifdef HAVE_SYS_UN_H
203 
204 int connection_connect_unix(struct connection_t *conn, const char *socket_path,
205  int *socket_error);
206 
207 #endif /* defined(HAVE_SYS_UN_H) */
208 
209 /** Maximum size of information that we can fit into SOCKS5 username
210  or password fields. */
211 #define MAX_SOCKS5_AUTH_FIELD_SIZE 255
212 
213 /** Total maximum size of information that we can fit into SOCKS5
214  username and password fields. */
215 #define MAX_SOCKS5_AUTH_SIZE_TOTAL 2*MAX_SOCKS5_AUTH_FIELD_SIZE
216 
217 int connection_proxy_connect(struct connection_t *conn, int type);
219 void log_failed_proxy_connection(struct connection_t *conn);
220 int get_proxy_addrport(struct tor_addr_t *addr, uint16_t *port,
221  int *proxy_type,
222  int *is_pt_out, const struct connection_t *conn);
223 
224 int retry_all_listeners(struct smartlist_t *new_conns,
225  int close_all_noncontrol);
226 
229 
230 ssize_t connection_bucket_write_limit(struct connection_t *conn, time_t now);
231 bool connection_dir_is_global_write_low(const struct connection_t *conn,
232  size_t attempt);
233 void connection_bucket_init(void);
234 void connection_bucket_adjust(const struct or_options_t *options);
235 void connection_bucket_refill_all(time_t now,
236  uint32_t now_ts);
238  bool is_global_bw);
240  bool is_global_bw);
243 
244 int connection_handle_read(struct connection_t *conn);
245 
246 int connection_buf_get_bytes(char *string, size_t len,
247  struct connection_t *conn);
248 int connection_buf_get_line(struct connection_t *conn, char *data,
249  size_t *data_len);
251  char **headers_out, size_t max_headerlen,
252  char **body_out, size_t *body_used,
253  size_t max_bodylen, int force_complete);
254 
255 int connection_wants_to_flush(struct connection_t *conn);
256 int connection_outbuf_too_full(struct connection_t *conn);
257 int connection_handle_write(struct connection_t *conn, int force);
258 int connection_flush(struct connection_t *conn);
259 
261  (const char *string, size_t len, struct connection_t *conn,
262  int zlib));
263 /* DOCDOC connection_write_to_buf */
264 static void connection_buf_add(const char *string, size_t len,
265  struct connection_t *conn);
266 void connection_dir_buf_add(const char *string, size_t len,
267  struct dir_connection_t *dir_conn, int done);
268 static inline void
269 connection_buf_add(const char *string, size_t len, struct connection_t *conn)
270 {
271  connection_write_to_buf_impl_(string, len, conn, 0);
272 }
273 void connection_buf_add_compress(const char *string, size_t len,
274  struct dir_connection_t *conn, int done);
275 void connection_buf_add_buf(struct connection_t *conn, struct buf_t *buf);
276 
277 size_t connection_get_inbuf_len(struct connection_t *conn);
278 size_t connection_get_outbuf_len(struct connection_t *conn);
279 struct connection_t *connection_get_by_global_id(uint64_t id);
280 
284  (int type,
285  const struct tor_addr_t *addr,
286  uint16_t port, int purpose));
288 struct connection_t *connection_get_by_type_state_rendquery(
289  int type, int state,
290  const char *rendquery);
291 struct smartlist_t *connection_list_by_type_state(int type, int state);
292 struct smartlist_t *connection_list_by_type_purpose(int type, int purpose);
294  int purpose,
295  const char *resource);
297  int purpose,
298  const char *resource,
299  int state);
300 
301 #define CONN_LEN_AND_FREE_TEMPLATE(sl) \
302  STMT_BEGIN \
303  int len = smartlist_len(sl); \
304  smartlist_free(sl); \
305  return len; \
306  STMT_END
307 
308 /** Return a count of directory connections that are fetching the item
309  * described by <b>purpose</b>/<b>resource</b>. */
310 static inline int
312  int purpose,
313  const char *resource)
314 {
316  purpose,
317  resource);
318  CONN_LEN_AND_FREE_TEMPLATE(conns);
319 }
320 
321 /** Return a count of directory connections that are fetching the item
322  * described by <b>purpose</b>/<b>resource</b>/<b>state</b>. */
323 static inline int
325  int purpose,
326  const char *resource,
327  int state)
328 {
329  struct smartlist_t *conns =
331  purpose,
332  resource,
333  state);
334  CONN_LEN_AND_FREE_TEMPLATE(conns);
335 }
336 
337 #undef CONN_LEN_AND_FREE_TEMPLATE
338 
339 int any_other_active_or_conns(const struct or_connection_t *this_conn);
340 
341 /* || 0 is for -Wparentheses-equality (-Wall?) appeasement under clang */
342 #define connection_speaks_cells(conn) (((conn)->type == CONN_TYPE_OR) || 0)
343 int connection_is_listener(struct connection_t *conn);
344 int connection_state_is_open(struct connection_t *conn);
346 
347 char *alloc_http_authenticator(const char *authenticator);
348 
349 void assert_connection_ok(struct connection_t *conn, time_t now);
351 void connection_dump_buffer_mem_stats(int severity);
352 
354  (const struct connection_t *conn, long apparent_skew, int trusted,
355  log_domain_mask_t domain, const char *received,
356  const char *source));
357 
358 int connection_is_moribund(struct connection_t *conn);
359 void connection_check_oos(int n_socks, int failed);
360 
361 /** Execute the statement <b>stmt</b>, which may log events concerning the
362  * connection <b>conn</b>. To prevent infinite loops, disable log messages
363  * being sent to controllers if <b>conn</b> is a control connection.
364  *
365  * Stmt must not contain any return or goto statements.
366  */
367 #define CONN_LOG_PROTECT(conn, stmt) \
368  STMT_BEGIN \
369  int _log_conn_is_control; \
370  tor_assert(conn); \
371  _log_conn_is_control = (conn->type == CONN_TYPE_CONTROL); \
372  if (_log_conn_is_control) \
373  disable_control_logging(); \
374  STMT_BEGIN stmt; STMT_END; \
375  if (_log_conn_is_control) \
376  enable_control_logging(); \
377  STMT_END
378 
379 #ifdef CONNECTION_PRIVATE
380 STATIC void connection_free_minimal(struct connection_t *conn);
381 
382 /* Used only by connection.c and test*.c */
384  (struct connection_t *conn,
385  const struct sockaddr *sa,
386  socklen_t sa_len,
387  const struct sockaddr *bindaddr,
388  socklen_t bindaddr_len,
389  int *socket_error));
390 MOCK_DECL(STATIC void, kill_conn_list_for_oos, (struct smartlist_t *conns));
391 MOCK_DECL(STATIC struct smartlist_t *, pick_oos_victims, (int n));
392 
393 #endif /* defined(CONNECTION_PRIVATE) */
394 
395 #endif /* !defined(TOR_CONNECTION_H) */
connection_t * connection_get_by_type_addr_port_purpose(int type, const tor_addr_t *addr, uint16_t port, int purpose)
Definition: connection.c:4797
const listener_connection_t * CONST_TO_LISTENER_CONN(const connection_t *c)
Definition: connection.c:247
void clock_skew_warning(const connection_t *conn, long apparent_skew, int trusted, log_domain_mask_t domain, const char *received, const char *source)
Definition: connection.c:5861
bool connection_dir_is_global_write_low(const connection_t *conn, size_t attempt)
Definition: connection.c:3531
int get_proxy_addrport(tor_addr_t *addr, uint16_t *port, int *proxy_type, int *is_pt_out, const connection_t *conn)
Definition: connection.c:5716
STATIC void connection_free_minimal(connection_t *conn)
Definition: connection.c:777
void connection_bucket_adjust(const or_options_t *options)
Definition: connection.c:3780
int any_other_active_or_conns(const or_connection_t *this_conn)
Definition: connection.c:4920
int connection_init_accepted_conn(connection_t *conn, const listener_connection_t *listener)
Definition: connection.c:2091
STATIC int connection_connect_sockaddr(connection_t *conn, const struct sockaddr *sa, socklen_t sa_len, const struct sockaddr *bindaddr, socklen_t bindaddr_len, int *socket_error)
Definition: connection.c:2163
STATIC smartlist_t * pick_oos_victims(int n)
Definition: connection.c:5307
STATIC void kill_conn_list_for_oos(smartlist_t *conns)
Definition: connection.c:5400
int connection_connect(connection_t *conn, const char *address, const tor_addr_t *addr, uint16_t port, int *socket_error)
Definition: connection.c:2396
void connection_mark_all_noncontrol_listeners(void)
Definition: connection.c:3305
struct smartlist_t * connection_dir_list_by_purpose_and_resource(int purpose, const char *resource)
Definition: connection.c:4871
const char * conn_state_to_string(int type, int state)
Definition: connection.c:302
void connection_dir_buf_add(const char *string, size_t len, struct dir_connection_t *dir_conn, int done)
Definition: connection.c:4707
struct connection_t * connection_get_by_type(int type)
Definition: connection.c:4818
void connection_mark_for_close_internal_(struct connection_t *conn, int line, const char *file)
Definition: connection.c:1117
struct listener_connection_t * listener_connection_new(int type, int socket_family)
Definition: connection.c:644
void assert_connection_ok(struct connection_t *conn, time_t now)
Definition: connection.c:5571
int connection_is_listener(struct connection_t *conn)
Definition: connection.c:4936
void connection_close_immediate(struct connection_t *conn)
Definition: connection.c:1043
struct edge_connection_t * edge_connection_new(int type, int socket_family)
Definition: connection.c:621
struct connection_t * connection_get_by_type_state(int type, int state)
Definition: connection.c:4827
struct entry_connection_t * entry_connection_new(int type, int socket_family)
Definition: connection.c:602
void connection_write_to_buf_impl_(const char *string, size_t len, struct connection_t *conn, int zlib)
Definition: connection.c:4675
struct connection_t * connection_new(int type, int socket_family)
Definition: connection.c:656
void log_failed_proxy_connection(struct connection_t *conn)
Definition: connection.c:5777
void connection_consider_empty_write_buckets(struct connection_t *conn)
Definition: connection.c:3727
static int connection_dir_count_by_purpose_and_resource(int purpose, const char *resource)
Definition: connection.h:311
void connection_dump_buffer_mem_stats(int severity)
Definition: connection.c:5522
int connection_wants_to_flush(struct connection_t *conn)
Definition: connection.c:4259
void connection_bucket_init(void)
Definition: connection.c:3755
int connection_flush(struct connection_t *conn)
Definition: connection.c:4599
void connection_free_(struct connection_t *conn)
Definition: connection.c:960
int connection_buf_get_line(struct connection_t *conn, char *data, size_t *data_len)
Definition: connection.c:4239
struct smartlist_t * connection_dir_list_by_purpose_resource_and_state(int purpose, const char *resource, int state)
Definition: connection.c:4889
const char * connection_describe(const connection_t *conn)
Definition: connection.c:543
int connection_fetch_from_buf_http(struct connection_t *conn, char **headers_out, size_t max_headerlen, char **body_out, size_t *body_used, size_t max_bodylen, int force_complete)
Definition: connection.c:4248
void connection_link_connections(struct connection_t *conn_a, struct connection_t *conn_b)
Definition: connection.c:745
int connection_or_nonopen_was_started_here(struct or_connection_t *conn)
int connection_buf_get_bytes(char *string, size_t len, struct connection_t *conn)
Definition: connection.c:4232
int connection_read_proxy_handshake(struct connection_t *conn)
Definition: connection.c:2903
void connection_write_bw_exhausted(struct connection_t *conn, bool is_global_bw)
Definition: connection.c:3687
const char * connection_describe_peer(const connection_t *conn)
Definition: connection.c:528
void connection_about_to_close_connection(struct connection_t *conn)
Definition: connection.c:1012
struct listener_connection_t * TO_LISTENER_CONN(struct connection_t *)
Definition: connection.c:234
const char * conn_type_to_string(int type)
Definition: connection.c:268
int conn_listener_type_supports_af_unix(int type)
Definition: connection.c:759
void connection_free_all(void)
Definition: connection.c:5818
void connection_consider_empty_read_buckets(struct connection_t *conn)
Definition: connection.c:3698
void connection_mark_for_close_(struct connection_t *conn, int line, const char *file)
Definition: connection.c:1076
char * alloc_http_authenticator(const char *authenticator)
Definition: connection.c:4999
ssize_t connection_bucket_write_limit(struct connection_t *conn, time_t now)
Definition: connection.c:3476
int connection_is_moribund(struct connection_t *conn)
Definition: connection.c:5421
void connection_read_bw_exhausted(struct connection_t *conn, bool is_global_bw)
Definition: connection.c:3672
int retry_all_listeners(struct smartlist_t *new_conns, int close_all_noncontrol)
Definition: connection.c:3203
int connection_state_is_open(struct connection_t *conn)
Definition: connection.c:4956
int connection_state_is_connecting(struct connection_t *conn)
Definition: connection.c:4976
void connection_buf_add_buf(struct connection_t *conn, struct buf_t *buf)
Definition: connection.c:4731
struct connection_t * connection_get_by_type_nonlinked(int type)
Definition: connection.c:4837
int connection_proxy_connect(struct connection_t *conn, int type)
Definition: connection.c:2750
int connection_outbuf_too_full(struct connection_t *conn)
Definition: connection.c:4269
void connection_mark_all_noncontrol_connections(void)
Definition: connection.c:3319
static int connection_dir_count_by_purpose_resource_and_state(int purpose, const char *resource, int state)
Definition: connection.h:324
struct dir_connection_t * dir_connection_new(int socket_family)
Definition: connection.c:561
struct or_connection_t * or_connection_new(int type, int socket_family)
Definition: connection.c:576
struct connection_t * connection_get_by_global_id(uint64_t id)
Definition: connection.c:4810
void connection_expire_held_open(void)
Definition: connection.c:1159
void connection_check_oos(int n_socks, int failed)
Definition: connection.c:5438
struct control_connection_t * control_connection_new(int socket_family)
Definition: connection.c:632
Headers for log.c.
uint64_t log_domain_mask_t
Definition: logging_types.h:21
Top-level declarations for the smartlist_t dynamic array type.
uint8_t state
Definition: connection_st.h:49
unsigned int type
Definition: connection_st.h:50
uint16_t port
unsigned int purpose
Definition: connection_st.h:51
tor_addr_t addr
uint8_t type
Definition: port_cfg_st.h:23
#define STATIC
Definition: testsupport.h:32
#define MOCK_DECL(rv, funcname, arglist)
Definition: testsupport.h:127