1 .\" Automatically generated by Pod::Man 2.16 (Pod::Simple 3.05)
4 .\" ========================================================================
5 .de Sh \" Subsection heading
13 .de Sp \" Vertical space (when we can't use .PP)
17 .de Vb \" Begin verbatim text
22 .de Ve \" End verbatim text
26 .\" Set up some character translations and predefined strings. \*(-- will
27 .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
28 .\" double quote, and \*(R" will give a right double quote. \*(C+ will
29 .\" give a nicer C++. Capital omega is used to do unbreakable dashes and
30 .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff,
31 .\" nothing in troff, for use with C<>.
33 .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
37 . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
38 . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch
51 .\" Escape single quotes in literal strings from groff's Unicode transform.
55 .\" If the F register is turned on, we'll generate index entries on stderr for
56 .\" titles (.TH), headers (.SH), subsections (.Sh), items (.Ip), and index
57 .\" entries marked with X<> in POD. Of course, you'll have to process the
58 .\" output yourself in some meaningful fashion.
61 . tm Index:\\$1\t\\n%\t"\\$2"
71 .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
72 .\" Fear. Run. Save yourself. No user-serviceable parts.
73 . \" fudge factors for nroff and troff
82 . ds #H ((1u-(\\\\n(.fu%2u))*.13m)
88 . \" simple accents for nroff and troff
98 . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
99 . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
100 . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
101 . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
102 . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
103 . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
105 . \" troff and (daisy-wheel) nroff accents
106 .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
107 .ds 8 \h'\*(#H'\(*b\h'-\*(#H'
108 .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
109 .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
110 .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
111 .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
112 .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
113 .ds ae a\h'-(\w'a'u*4/10)'e
114 .ds Ae A\h'-(\w'A'u*4/10)'E
115 . \" corrections for vroff
116 .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
117 .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
118 . \" for low resolution devices (crt and lpr)
119 .if \n(.H>23 .if \n(.V>19 \
132 .\" ========================================================================
134 .IX Title "BIO_f_ssl 3"
135 .TH BIO_f_ssl 3 "2010-02-27" "0.9.8m" "OpenSSL"
136 .\" For nroff, turn off justification. Always turn off hyphenation; it makes
137 .\" way too many mistakes in technical documents.
141 BIO_f_ssl, BIO_set_ssl, BIO_get_ssl, BIO_set_ssl_mode, BIO_set_ssl_renegotiate_bytes,
142 BIO_get_num_renegotiates, BIO_set_ssl_renegotiate_timeout, BIO_new_ssl,
143 BIO_new_ssl_connect, BIO_new_buffer_ssl_connect, BIO_ssl_copy_session_id,
144 BIO_ssl_shutdown \- SSL BIO
146 .IX Header "SYNOPSIS"
148 \& #include <openssl/bio.h>
149 \& #include <openssl/ssl.h>
151 \& BIO_METHOD *BIO_f_ssl(void);
153 \& #define BIO_set_ssl(b,ssl,c) BIO_ctrl(b,BIO_C_SET_SSL,c,(char *)ssl)
154 \& #define BIO_get_ssl(b,sslp) BIO_ctrl(b,BIO_C_GET_SSL,0,(char *)sslp)
155 \& #define BIO_set_ssl_mode(b,client) BIO_ctrl(b,BIO_C_SSL_MODE,client,NULL)
156 \& #define BIO_set_ssl_renegotiate_bytes(b,num) \e
157 \& BIO_ctrl(b,BIO_C_SET_SSL_RENEGOTIATE_BYTES,num,NULL);
158 \& #define BIO_set_ssl_renegotiate_timeout(b,seconds) \e
159 \& BIO_ctrl(b,BIO_C_SET_SSL_RENEGOTIATE_TIMEOUT,seconds,NULL);
160 \& #define BIO_get_num_renegotiates(b) \e
161 \& BIO_ctrl(b,BIO_C_SET_SSL_NUM_RENEGOTIATES,0,NULL);
163 \& BIO *BIO_new_ssl(SSL_CTX *ctx,int client);
164 \& BIO *BIO_new_ssl_connect(SSL_CTX *ctx);
165 \& BIO *BIO_new_buffer_ssl_connect(SSL_CTX *ctx);
166 \& int BIO_ssl_copy_session_id(BIO *to,BIO *from);
167 \& void BIO_ssl_shutdown(BIO *bio);
169 \& #define BIO_do_handshake(b) BIO_ctrl(b,BIO_C_DO_STATE_MACHINE,0,NULL)
172 .IX Header "DESCRIPTION"
173 \&\fIBIO_f_ssl()\fR returns the \s-1SSL\s0 \s-1BIO\s0 method. This is a filter \s-1BIO\s0 which
174 is a wrapper round the OpenSSL \s-1SSL\s0 routines adding a \s-1BIO\s0 \*(L"flavour\*(R" to
177 I/O performed on an \s-1SSL\s0 \s-1BIO\s0 communicates using the \s-1SSL\s0 protocol with
178 the SSLs read and write BIOs. If an \s-1SSL\s0 connection is not established
179 then an attempt is made to establish one on the first I/O call.
181 If a \s-1BIO\s0 is appended to an \s-1SSL\s0 \s-1BIO\s0 using \fIBIO_push()\fR it is automatically
182 used as the \s-1SSL\s0 BIOs read and write BIOs.
184 Calling \fIBIO_reset()\fR on an \s-1SSL\s0 \s-1BIO\s0 closes down any current \s-1SSL\s0 connection
185 by calling \fISSL_shutdown()\fR. \fIBIO_reset()\fR is then sent to the next \s-1BIO\s0 in
186 the chain: this will typically disconnect the underlying transport.
187 The \s-1SSL\s0 \s-1BIO\s0 is then reset to the initial accept or connect state.
189 If the close flag is set when an \s-1SSL\s0 \s-1BIO\s0 is freed then the internal
190 \&\s-1SSL\s0 structure is also freed using \fISSL_free()\fR.
192 \&\fIBIO_set_ssl()\fR sets the internal \s-1SSL\s0 pointer of \s-1BIO\s0 \fBb\fR to \fBssl\fR using
193 the close flag \fBc\fR.
195 \&\fIBIO_get_ssl()\fR retrieves the \s-1SSL\s0 pointer of \s-1BIO\s0 \fBb\fR, it can then be
196 manipulated using the standard \s-1SSL\s0 library functions.
198 \&\fIBIO_set_ssl_mode()\fR sets the \s-1SSL\s0 \s-1BIO\s0 mode to \fBclient\fR. If \fBclient\fR
199 is 1 client mode is set. If \fBclient\fR is 0 server mode is set.
201 \&\fIBIO_set_ssl_renegotiate_bytes()\fR sets the renegotiate byte count
202 to \fBnum\fR. When set after every \fBnum\fR bytes of I/O (read and write)
203 the \s-1SSL\s0 session is automatically renegotiated. \fBnum\fR must be at
206 \&\fIBIO_set_ssl_renegotiate_timeout()\fR sets the renegotiate timeout to
207 \&\fBseconds\fR. When the renegotiate timeout elapses the session is
208 automatically renegotiated.
210 \&\fIBIO_get_num_renegotiates()\fR returns the total number of session
211 renegotiations due to I/O or timeout.
213 \&\fIBIO_new_ssl()\fR allocates an \s-1SSL\s0 \s-1BIO\s0 using \s-1SSL_CTX\s0 \fBctx\fR and using
214 client mode if \fBclient\fR is non zero.
216 \&\fIBIO_new_ssl_connect()\fR creates a new \s-1BIO\s0 chain consisting of an
217 \&\s-1SSL\s0 \s-1BIO\s0 (using \fBctx\fR) followed by a connect \s-1BIO\s0.
219 \&\fIBIO_new_buffer_ssl_connect()\fR creates a new \s-1BIO\s0 chain consisting
220 of a buffering \s-1BIO\s0, an \s-1SSL\s0 \s-1BIO\s0 (using \fBctx\fR) and a connect
223 \&\fIBIO_ssl_copy_session_id()\fR copies an \s-1SSL\s0 session id between
224 \&\s-1BIO\s0 chains \fBfrom\fR and \fBto\fR. It does this by locating the
225 \&\s-1SSL\s0 BIOs in each chain and calling \fISSL_copy_session_id()\fR on
226 the internal \s-1SSL\s0 pointer.
228 \&\fIBIO_ssl_shutdown()\fR closes down an \s-1SSL\s0 connection on \s-1BIO\s0
229 chain \fBbio\fR. It does this by locating the \s-1SSL\s0 \s-1BIO\s0 in the
230 chain and calling \fISSL_shutdown()\fR on its internal \s-1SSL\s0
233 \&\fIBIO_do_handshake()\fR attempts to complete an \s-1SSL\s0 handshake on the
234 supplied \s-1BIO\s0 and establish the \s-1SSL\s0 connection. It returns 1
235 if the connection was established successfully. A zero or negative
236 value is returned if the connection could not be established, the
237 call \fIBIO_should_retry()\fR should be used for non blocking connect BIOs
238 to determine if the call should be retried. If an \s-1SSL\s0 connection has
239 already been established this call has no effect.
242 \&\s-1SSL\s0 BIOs are exceptional in that if the underlying transport
243 is non blocking they can still request a retry in exceptional
244 circumstances. Specifically this will happen if a session
245 renegotiation takes place during a \fIBIO_read()\fR operation, one
246 case where this happens is when \s-1SGC\s0 or step up occurs.
248 In OpenSSL 0.9.6 and later the \s-1SSL\s0 flag \s-1SSL_AUTO_RETRY\s0 can be
249 set to disable this behaviour. That is when this flag is set
250 an \s-1SSL\s0 \s-1BIO\s0 using a blocking transport will never request a
253 Since unknown \fIBIO_ctrl()\fR operations are sent through filter
254 BIOs the servers name and port can be set using \fIBIO_set_host()\fR
255 on the \s-1BIO\s0 returned by \fIBIO_new_ssl_connect()\fR without having
256 to locate the connect \s-1BIO\s0 first.
258 Applications do not have to call \fIBIO_do_handshake()\fR but may wish
259 to do so to separate the handshake process from other I/O
262 .IX Header "RETURN VALUES"
266 This \s-1SSL/TLS\s0 client example, attempts to retrieve a page from an
267 \&\s-1SSL/TLS\s0 web server. The I/O routines are identical to those of the
268 unencrypted example in \fIBIO_s_connect\fR\|(3).
273 \& char tmpbuf[1024];
277 \& ERR_load_crypto_strings();
278 \& ERR_load_SSL_strings();
279 \& OpenSSL_add_all_algorithms();
281 \& /* We would seed the PRNG here if the platform didn\*(Aqt
282 \& * do it automatically
285 \& ctx = SSL_CTX_new(SSLv23_client_method());
287 \& /* We\*(Aqd normally set some stuff like the verify paths and
288 \& * mode here because as things stand this will connect to
289 \& * any server whose certificate is signed by any CA.
292 \& sbio = BIO_new_ssl_connect(ctx);
294 \& BIO_get_ssl(sbio, &ssl);
297 \& fprintf(stderr, "Can\*(Aqt locate SSL pointer\en");
298 \& /* whatever ... */
301 \& /* Don\*(Aqt want any retries */
302 \& SSL_set_mode(ssl, SSL_MODE_AUTO_RETRY);
304 \& /* We might want to do other things with ssl here */
306 \& BIO_set_conn_hostname(sbio, "localhost:https");
308 \& out = BIO_new_fp(stdout, BIO_NOCLOSE);
309 \& if(BIO_do_connect(sbio) <= 0) {
310 \& fprintf(stderr, "Error connecting to server\en");
311 \& ERR_print_errors_fp(stderr);
312 \& /* whatever ... */
315 \& if(BIO_do_handshake(sbio) <= 0) {
316 \& fprintf(stderr, "Error establishing SSL connection\en");
317 \& ERR_print_errors_fp(stderr);
318 \& /* whatever ... */
321 \& /* Could examine ssl here to get connection info */
323 \& BIO_puts(sbio, "GET / HTTP/1.0\en\en");
325 \& len = BIO_read(sbio, tmpbuf, 1024);
326 \& if(len <= 0) break;
327 \& BIO_write(out, tmpbuf, len);
329 \& BIO_free_all(sbio);
333 Here is a simple server example. It makes use of a buffering
334 \&\s-1BIO\s0 to allow lines to be read from the \s-1SSL\s0 \s-1BIO\s0 using BIO_gets.
335 It creates a pseudo web page containing the actual request from
336 a client and also echoes the request to standard output.
339 \& BIO *sbio, *bbio, *acpt, *out;
341 \& char tmpbuf[1024];
345 \& ERR_load_crypto_strings();
346 \& ERR_load_SSL_strings();
347 \& OpenSSL_add_all_algorithms();
349 \& /* Might seed PRNG here */
351 \& ctx = SSL_CTX_new(SSLv23_server_method());
353 \& if (!SSL_CTX_use_certificate_file(ctx,"server.pem",SSL_FILETYPE_PEM)
354 \& || !SSL_CTX_use_PrivateKey_file(ctx,"server.pem",SSL_FILETYPE_PEM)
355 \& || !SSL_CTX_check_private_key(ctx)) {
357 \& fprintf(stderr, "Error setting up SSL_CTX\en");
358 \& ERR_print_errors_fp(stderr);
362 \& /* Might do other things here like setting verify locations and
363 \& * DH and/or RSA temporary key callbacks
366 \& /* New SSL BIO setup as server */
367 \& sbio=BIO_new_ssl(ctx,0);
369 \& BIO_get_ssl(sbio, &ssl);
372 \& fprintf(stderr, "Can\*(Aqt locate SSL pointer\en");
373 \& /* whatever ... */
376 \& /* Don\*(Aqt want any retries */
377 \& SSL_set_mode(ssl, SSL_MODE_AUTO_RETRY);
379 \& /* Create the buffering BIO */
381 \& bbio = BIO_new(BIO_f_buffer());
383 \& /* Add to chain */
384 \& sbio = BIO_push(bbio, sbio);
386 \& acpt=BIO_new_accept("4433");
388 \& /* By doing this when a new connection is established
389 \& * we automatically have sbio inserted into it. The
390 \& * BIO chain is now \*(Aqswallowed\*(Aq by the accept BIO and
391 \& * will be freed when the accept BIO is freed.
394 \& BIO_set_accept_bios(acpt,sbio);
396 \& out = BIO_new_fp(stdout, BIO_NOCLOSE);
398 \& /* Setup accept BIO */
399 \& if(BIO_do_accept(acpt) <= 0) {
400 \& fprintf(stderr, "Error setting up accept BIO\en");
401 \& ERR_print_errors_fp(stderr);
405 \& /* Now wait for incoming connection */
406 \& if(BIO_do_accept(acpt) <= 0) {
407 \& fprintf(stderr, "Error in connection\en");
408 \& ERR_print_errors_fp(stderr);
412 \& /* We only want one connection so remove and free
416 \& sbio = BIO_pop(acpt);
418 \& BIO_free_all(acpt);
420 \& if(BIO_do_handshake(sbio) <= 0) {
421 \& fprintf(stderr, "Error in SSL handshake\en");
422 \& ERR_print_errors_fp(stderr);
426 \& BIO_puts(sbio, "HTTP/1.0 200 OK\er\enContent\-type: text/plain\er\en\er\en");
427 \& BIO_puts(sbio, "\er\enConnection Established\er\enRequest headers:\er\en");
428 \& BIO_puts(sbio, "\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\er\en");
431 \& len = BIO_gets(sbio, tmpbuf, 1024);
432 \& if(len <= 0) break;
433 \& BIO_write(sbio, tmpbuf, len);
434 \& BIO_write(out, tmpbuf, len);
435 \& /* Look for blank line signifying end of headers*/
436 \& if((tmpbuf[0] == \*(Aq\er\*(Aq) || (tmpbuf[0] == \*(Aq\en\*(Aq)) break;
439 \& BIO_puts(sbio, "\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\er\en");
440 \& BIO_puts(sbio, "\er\en");
442 \& /* Since there is a buffering BIO present we had better flush it */
445 \& BIO_free_all(sbio);
448 .IX Header "SEE ALSO"