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author | schwarze <> | 2015-02-16 16:42:14 +0000 |
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committer | schwarze <> | 2015-02-16 16:42:14 +0000 |
commit | 9a3026fb0a89a15ea2def3629cc13a69f1fc678c (patch) | |
tree | 28ac935f3dd22b133413a78861848f9501389a34 /src/lib/libcrypto/man/BIO_s_accept.3 | |
parent | 4ab59c54f9da1075f740a1004c326b0784ed4de0 (diff) | |
download | openbsd-9a3026fb0a89a15ea2def3629cc13a69f1fc678c.tar.gz openbsd-9a3026fb0a89a15ea2def3629cc13a69f1fc678c.tar.bz2 openbsd-9a3026fb0a89a15ea2def3629cc13a69f1fc678c.zip |
third batch of perlpod(1) to mdoc(7) conversion
Diffstat (limited to 'src/lib/libcrypto/man/BIO_s_accept.3')
-rw-r--r-- | src/lib/libcrypto/man/BIO_s_accept.3 | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/src/lib/libcrypto/man/BIO_s_accept.3 b/src/lib/libcrypto/man/BIO_s_accept.3 new file mode 100644 index 0000000000..f5adfcc07c --- /dev/null +++ b/src/lib/libcrypto/man/BIO_s_accept.3 | |||
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1 | .Dd $Mdocdate: February 16 2015 $ | ||
2 | .Dt BIO_S_ACCEPT 3 | ||
3 | .Os | ||
4 | .Sh NAME | ||
5 | .Nm BIO_s_accept , | ||
6 | .Nm BIO_set_accept_port , | ||
7 | .Nm BIO_get_accept_port , | ||
8 | .Nm BIO_new_accept , | ||
9 | .Nm BIO_set_nbio_accept , | ||
10 | .Nm BIO_set_accept_bios , | ||
11 | .Nm BIO_set_bind_mode , | ||
12 | .Nm BIO_get_bind_mode , | ||
13 | .Nm BIO_do_accept | ||
14 | .Nd accept BIO | ||
15 | .Sh SYNOPSIS | ||
16 | .In openssl/bio.h | ||
17 | .Ft BIO_METHOD * | ||
18 | .Fo BIO_s_accept | ||
19 | .Fa void | ||
20 | .Fc | ||
21 | .Ft long | ||
22 | .Fo BIO_set_accept_port | ||
23 | .Fa "BIO *b" | ||
24 | .Fa "char *name" | ||
25 | .Fc | ||
26 | .Ft char * | ||
27 | .Fo BIO_get_accept_port | ||
28 | .Fa "BIO *b" | ||
29 | .Fc | ||
30 | .Ft BIO * | ||
31 | .Fo BIO_new_accept | ||
32 | .Fa "char *host_port" | ||
33 | .Fc | ||
34 | .Ft long | ||
35 | .Fo BIO_set_nbio_accept | ||
36 | .Fa "BIO *b" | ||
37 | .Fa "int n" | ||
38 | .Fc | ||
39 | .Ft long | ||
40 | .Fo BIO_set_accept_bios | ||
41 | .Fa "BIO *b" | ||
42 | .Fa "char *bio" | ||
43 | .Fc | ||
44 | .Ft long | ||
45 | .Fo BIO_set_bind_mode | ||
46 | .Fa "BIO *b" | ||
47 | .Fa "long mode" | ||
48 | .Fc | ||
49 | .Ft long | ||
50 | .Fo BIO_get_bind_mode | ||
51 | .Fa "BIO *b" | ||
52 | .Fa "long dummy" | ||
53 | .Fc | ||
54 | .Fd #define BIO_BIND_NORMAL 0 | ||
55 | .Fd #define BIO_BIND_REUSEADDR_IF_UNUSED 1 | ||
56 | .Fd #define BIO_BIND_REUSEADDR 2 | ||
57 | .Ft int | ||
58 | .Fo BIO_do_accept | ||
59 | .Fa "BIO *b" | ||
60 | .Fc | ||
61 | .Sh DESCRIPTION | ||
62 | .Fn BIO_s_accept | ||
63 | returns the accept BIO method. | ||
64 | This is a wrapper round the platform's TCP/IP socket accept routines. | ||
65 | .Pp | ||
66 | Using accept BIOs, TCP/IP connections can be accepted | ||
67 | and data transferred using only BIO routines. | ||
68 | In this way any platform specific operations | ||
69 | are hidden by the BIO abstraction. | ||
70 | .Pp | ||
71 | Read and write operations on an accept BIO | ||
72 | will perform I/O on the underlying connection. | ||
73 | If no connection is established and the port (see below) is set up | ||
74 | properly then the BIO waits for an incoming connection. | ||
75 | .Pp | ||
76 | Accept BIOs support | ||
77 | .Xr BIO_puts 3 | ||
78 | but not | ||
79 | .Xr BIO_gets 3 . | ||
80 | .Pp | ||
81 | If the close flag is set on an accept BIO, then any active | ||
82 | connection on that chain is shutdown and the socket closed when | ||
83 | the BIO is freed. | ||
84 | .Pp | ||
85 | Calling | ||
86 | .Xr BIO_reset 3 | ||
87 | on a accept BIO will close any active connection and reset the BIO | ||
88 | into a state where it awaits another incoming connection. | ||
89 | .Pp | ||
90 | .Xr BIO_get_fd 3 | ||
91 | and | ||
92 | .Xr BIO_set_fd 3 | ||
93 | can be called to retrieve or set the accept socket. | ||
94 | See | ||
95 | .Xr BIO_s_fd 3 . | ||
96 | .Pp | ||
97 | .Fn BIO_set_accept_port | ||
98 | uses the string | ||
99 | .Fa name | ||
100 | to set the accept port. | ||
101 | The port is represented as a string of the form | ||
102 | .Ar host : Ns Ar port , | ||
103 | where | ||
104 | .Ar host | ||
105 | is the interface to use and | ||
106 | .Ar port | ||
107 | is the port. | ||
108 | Either or both values can be | ||
109 | .Qq * | ||
110 | which is interpreted as meaning any interface or port respectively. | ||
111 | .Ar port | ||
112 | has the same syntax as the port specified in | ||
113 | .Xr BIO_set_conn_port 3 | ||
114 | for connect BIOs. | ||
115 | It can be a numerical port string or a string to lookup using | ||
116 | .Xr getservbyname 3 | ||
117 | and a string table. | ||
118 | .Pp | ||
119 | .Fn BIO_new_accept | ||
120 | combines | ||
121 | .Xr BIO_new 3 | ||
122 | and | ||
123 | .Fn BIO_set_accept_port | ||
124 | into a single call. | ||
125 | It creates a new accept BIO with port | ||
126 | .Fa host_port . | ||
127 | .Pp | ||
128 | .Fn BIO_set_nbio_accept | ||
129 | sets the accept socket to blocking mode (the default) if | ||
130 | .Fa n | ||
131 | is 0 or non blocking mode if | ||
132 | .Fa n | ||
133 | is 1. | ||
134 | .Pp | ||
135 | .Fn BIO_set_accept_bios | ||
136 | can be used to set a chain of BIOs which will be duplicated | ||
137 | and prepended to the chain when an incoming connection is received. | ||
138 | This is useful if, for example, a buffering or SSL BIO | ||
139 | is required for each connection. | ||
140 | The chain of BIOs must not be freed after this call, | ||
141 | they will be automatically freed when the accept BIO is freed. | ||
142 | .Pp | ||
143 | .Fn BIO_set_bind_mode | ||
144 | and | ||
145 | .Fn BIO_get_bind_mode | ||
146 | set and retrieve the current bind mode. | ||
147 | If | ||
148 | .Dv BIO_BIND_NORMAL Pq the default | ||
149 | is set, then another socket cannot be bound to the same port. | ||
150 | If | ||
151 | .Dv BIO_BIND_REUSEADDR | ||
152 | is set, then other sockets can bind to the same port. | ||
153 | If | ||
154 | .Dv BIO_BIND_REUSEADDR_IF_UNUSED | ||
155 | is set, then an attempt is first made to use | ||
156 | .Dv BIO_BIN_NORMAL ; | ||
157 | if this fails and the port is not in use, | ||
158 | then a second attempt is made using | ||
159 | .Dv BIO_BIND_REUSEADDR . | ||
160 | .Pp | ||
161 | .Fn BIO_do_accept | ||
162 | serves two purposes. | ||
163 | When it is first called, after the accept BIO has been setup, | ||
164 | it will attempt to create the accept socket and bind an address to it. | ||
165 | Second and subsequent calls to | ||
166 | .Fn BIO_do_accept | ||
167 | will await an incoming connection, or request a retry in non blocking mode. | ||
168 | .Sh NOTES | ||
169 | When an accept BIO is at the end of a chain, it will await an | ||
170 | incoming connection before processing I/O calls. | ||
171 | When an accept BIO is not at then end of a chain, | ||
172 | it passes I/O calls to the next BIO in the chain. | ||
173 | .Pp | ||
174 | When a connection is established a new socket BIO is created | ||
175 | for the connection and appended to the chain. | ||
176 | That is the chain is now accept->socket. | ||
177 | This effectively means that attempting I/O on an initial accept | ||
178 | socket will await an incoming connection then perform I/O on it. | ||
179 | .Pp | ||
180 | If any additional BIOs have been set using | ||
181 | .Fn BIO_set_accept_bios , | ||
182 | then they are placed between the socket and the accept BIO, | ||
183 | that is the chain will be accept->otherbios->socket. | ||
184 | .Pp | ||
185 | If a server wishes to process multiple connections (as is normally | ||
186 | the case), then the accept BIO must be made available for further | ||
187 | incoming connections. | ||
188 | This can be done by waiting for a connection and then calling: | ||
189 | .Pp | ||
190 | .Dl connection = BIO_pop(accept); | ||
191 | .Pp | ||
192 | After this call, | ||
193 | .Sy connection | ||
194 | will contain a BIO for the recently established connection and | ||
195 | .Sy accept | ||
196 | will now be a single BIO again which can be used | ||
197 | to await further incoming connections. | ||
198 | If no further connections will be accepted, the | ||
199 | .Sy accept | ||
200 | can be freed using | ||
201 | .Xr BIO_free 3 . | ||
202 | .Pp | ||
203 | If only a single connection will be processed, | ||
204 | it is possible to perform I/O using the accept BIO itself. | ||
205 | This is often undesirable however because the accept BIO | ||
206 | will still accept additional incoming connections. | ||
207 | This can be resolved by using | ||
208 | .Xr BIO_pop 3 | ||
209 | (see above) and freeing up the accept BIO after the initial connection. | ||
210 | .Pp | ||
211 | If the underlying accept socket is non-blocking and | ||
212 | .Fn BIO_do_accept | ||
213 | is called to await an incoming connection, it is possible for | ||
214 | .Xr BIO_should_io_special 3 | ||
215 | with the reason | ||
216 | .Dv BIO_RR_ACCEPT . | ||
217 | If this happens, then it is an indication that an accept attempt | ||
218 | would block: the application should take appropriate action | ||
219 | to wait until the underlying socket has accepted a connection | ||
220 | and retry the call. | ||
221 | .Pp | ||
222 | .Fn BIO_set_accept_port , | ||
223 | .Fn BIO_get_accept_port , | ||
224 | .Fn BIO_set_nbio_accept , | ||
225 | .Fn BIO_set_accept_bios , | ||
226 | .Fn BIO_set_bind_mode , | ||
227 | .Fn BIO_get_bind_mode , | ||
228 | and | ||
229 | .Fn BIO_do_accept | ||
230 | are macros. | ||
231 | .Sh EXAMPLES | ||
232 | This example accepts two connections on port 4444, | ||
233 | sends messages down each and finally closes both down. | ||
234 | .Bd -literal -offset 2n | ||
235 | BIO *abio, *cbio, *cbio2; | ||
236 | ERR_load_crypto_strings(); | ||
237 | abio = BIO_new_accept("4444"); | ||
238 | |||
239 | /* First call to BIO_accept() sets up accept BIO */ | ||
240 | if (BIO_do_accept(abio) <= 0) { | ||
241 | fprintf(stderr, "Error setting up accept\en"); | ||
242 | ERR_print_errors_fp(stderr); | ||
243 | exit(0); | ||
244 | } | ||
245 | |||
246 | /* Wait for incoming connection */ | ||
247 | if (BIO_do_accept(abio) <= 0) { | ||
248 | fprintf(stderr, "Error accepting connection\en"); | ||
249 | ERR_print_errors_fp(stderr); | ||
250 | exit(0); | ||
251 | } | ||
252 | fprintf(stderr, "Connection 1 established\en"); | ||
253 | |||
254 | /* Retrieve BIO for connection */ | ||
255 | cbio = BIO_pop(abio); | ||
256 | |||
257 | BIO_puts(cbio, "Connection 1: Sending out Data on initial connection\en"); | ||
258 | fprintf(stderr, "Sent out data on connection 1\en"); | ||
259 | |||
260 | /* Wait for another connection */ | ||
261 | if (BIO_do_accept(abio) <= 0) { | ||
262 | fprintf(stderr, "Error accepting connection\en"); | ||
263 | ERR_print_errors_fp(stderr); | ||
264 | exit(0); | ||
265 | } | ||
266 | fprintf(stderr, "Connection 2 established\en"); | ||
267 | |||
268 | /* Close accept BIO to refuse further connections */ | ||
269 | cbio2 = BIO_pop(abio); | ||
270 | BIO_free(abio); | ||
271 | |||
272 | BIO_puts(cbio2, "Connection 2: Sending out Data on second\en"); | ||
273 | fprintf(stderr, "Sent out data on connection 2\en"); | ||
274 | BIO_puts(cbio, "Connection 1: Second connection established\en"); | ||
275 | |||
276 | /* Close the two established connections */ | ||
277 | BIO_free(cbio); | ||
278 | BIO_free(cbio2); | ||
279 | .Ed | ||