PostgreSQL Source Code: src/backend/libpq/be-secure-openssl.c Source File

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be-secure-openssl.c
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1/*-------------------------------------------------------------------------
2 *
3 * be-secure-openssl.c
4 * functions for OpenSSL support in the backend.
5 *
6 *
7 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
8 * Portions Copyright (c) 1994, Regents of the University of California
9 *
10 *
11 * IDENTIFICATION
12 * src/backend/libpq/be-secure-openssl.c
13 *
14 *-------------------------------------------------------------------------
15 */
16
17#include "postgres.h"
18
19#include <sys/stat.h>
20#include <signal.h>
21#include <fcntl.h>
22#include <ctype.h>
23#include <sys/socket.h>
24#include <unistd.h>
25#include <netdb.h>
26#include <netinet/in.h>
27#include <netinet/tcp.h>
28#include <arpa/inet.h>
29
30#include "common/string.h"
31#include "libpq/libpq.h"
32#include "miscadmin.h"
33#include "pgstat.h"
34#include "storage/fd.h"
35#include "storage/latch.h"
36#include "utils/guc.h"
37#include "utils/memutils.h"
38
39/*
40 * These SSL-related #includes must come after all system-provided headers.
41 * This ensures that OpenSSL can take care of conflicts with Windows'
42 * <wincrypt.h> by #undef'ing the conflicting macros. (We don't directly
43 * include <wincrypt.h>, but some other Windows headers do.)
44 */
45#include "common/openssl.h"
46#include <openssl/bn.h>
47#include <openssl/conf.h>
48#include <openssl/dh.h>
49#ifndef OPENSSL_NO_ECDH
50#include <openssl/ec.h>
51#endif
52#include <openssl/x509v3.h>
53
54
55/* default init hook can be overridden by a shared library */
56static void default_openssl_tls_init(SSL_CTX *context, bool isServerStart);
57 openssl_tls_init_hook_typ openssl_tls_init_hook = default_openssl_tls_init;
58
59static int port_bio_read(BIO *h, char *buf, int size);
60static int port_bio_write(BIO *h, const char *buf, int size);
61static BIO_METHOD *port_bio_method(void);
62static int ssl_set_port_bio(Port *port);
63
64static DH *load_dh_file(char *filename, bool isServerStart);
65static DH *load_dh_buffer(const char *buffer, size_t len);
66static int ssl_external_passwd_cb(char *buf, int size, int rwflag, void *userdata);
67static int dummy_ssl_passwd_cb(char *buf, int size, int rwflag, void *userdata);
68static int verify_cb(int ok, X509_STORE_CTX *ctx);
69static void info_cb(const SSL *ssl, int type, int args);
70static int alpn_cb(SSL *ssl,
71 const unsigned char **out,
72 unsigned char *outlen,
73 const unsigned char *in,
74 unsigned int inlen,
75 void *userdata);
76static bool initialize_dh(SSL_CTX *context, bool isServerStart);
77static bool initialize_ecdh(SSL_CTX *context, bool isServerStart);
78static const char *SSLerrmessageExt(unsigned long ecode, const char *replacement);
79static const char *SSLerrmessage(unsigned long ecode);
80
81static char *X509_NAME_to_cstring(X509_NAME *name);
82
83 static SSL_CTX *SSL_context = NULL;
84 static bool dummy_ssl_passwd_cb_called = false;
85 static bool ssl_is_server_start;
86
87static int ssl_protocol_version_to_openssl(int v);
88static const char *ssl_protocol_version_to_string(int v);
89
90/* for passing data back from verify_cb() */
91 static const char *cert_errdetail;
92
93/* ------------------------------------------------------------ */
94/* Public interface */
95/* ------------------------------------------------------------ */
96
97int
98 be_tls_init(bool isServerStart)
99{
100 SSL_CTX *context;
101 int ssl_ver_min = -1;
102 int ssl_ver_max = -1;
103
104 /*
105 * Create a new SSL context into which we'll load all the configuration
106 * settings. If we fail partway through, we can avoid memory leakage by
107 * freeing this context; we don't install it as active until the end.
108 *
109 * We use SSLv23_method() because it can negotiate use of the highest
110 * mutually supported protocol version, while alternatives like
111 * TLSv1_2_method() permit only one specific version. Note that we don't
112 * actually allow SSL v2 or v3, only TLS protocols (see below).
113 */
114 context = SSL_CTX_new(SSLv23_method());
115 if (!context)
116 {
117 ereport(isServerStart ? FATAL : LOG,
118 (errmsg("could not create SSL context: %s",
119 SSLerrmessage(ERR_get_error()))));
120 goto error;
121 }
122
123 /*
124 * Disable OpenSSL's moving-write-buffer sanity check, because it causes
125 * unnecessary failures in nonblocking send cases.
126 */
127 SSL_CTX_set_mode(context, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
128
129 /*
130 * Call init hook (usually to set password callback)
131 */
132 (*openssl_tls_init_hook) (context, isServerStart);
133
134 /* used by the callback */
135 ssl_is_server_start = isServerStart;
136
137 /*
138 * Load and verify server's certificate and private key
139 */
140 if (SSL_CTX_use_certificate_chain_file(context, ssl_cert_file) != 1)
141 {
142 ereport(isServerStart ? FATAL : LOG,
143 (errcode(ERRCODE_CONFIG_FILE_ERROR),
144 errmsg("could not load server certificate file \"%s\": %s",
145 ssl_cert_file, SSLerrmessage(ERR_get_error()))));
146 goto error;
147 }
148
149 if (!check_ssl_key_file_permissions(ssl_key_file, isServerStart))
150 goto error;
151
152 /*
153 * OK, try to load the private key file.
154 */
155 dummy_ssl_passwd_cb_called = false;
156
157 if (SSL_CTX_use_PrivateKey_file(context,
158 ssl_key_file,
159 SSL_FILETYPE_PEM) != 1)
160 {
161 if (dummy_ssl_passwd_cb_called)
162 ereport(isServerStart ? FATAL : LOG,
163 (errcode(ERRCODE_CONFIG_FILE_ERROR),
164 errmsg("private key file \"%s\" cannot be reloaded because it requires a passphrase",
165 ssl_key_file)));
166 else
167 ereport(isServerStart ? FATAL : LOG,
168 (errcode(ERRCODE_CONFIG_FILE_ERROR),
169 errmsg("could not load private key file \"%s\": %s",
170 ssl_key_file, SSLerrmessage(ERR_get_error()))));
171 goto error;
172 }
173
174 if (SSL_CTX_check_private_key(context) != 1)
175 {
176 ereport(isServerStart ? FATAL : LOG,
177 (errcode(ERRCODE_CONFIG_FILE_ERROR),
178 errmsg("check of private key failed: %s",
179 SSLerrmessage(ERR_get_error()))));
180 goto error;
181 }
182
183 if (ssl_min_protocol_version)
184 {
185 ssl_ver_min = ssl_protocol_version_to_openssl(ssl_min_protocol_version);
186
187 if (ssl_ver_min == -1)
188 {
189 ereport(isServerStart ? FATAL : LOG,
190 /*- translator: first %s is a GUC option name, second %s is its value */
191 (errmsg("\"%s\" setting \"%s\" not supported by this build",
192 "ssl_min_protocol_version",
193 GetConfigOption("ssl_min_protocol_version",
194 false, false))));
195 goto error;
196 }
197
198 if (!SSL_CTX_set_min_proto_version(context, ssl_ver_min))
199 {
200 ereport(isServerStart ? FATAL : LOG,
201 (errmsg("could not set minimum SSL protocol version")));
202 goto error;
203 }
204 }
205
206 if (ssl_max_protocol_version)
207 {
208 ssl_ver_max = ssl_protocol_version_to_openssl(ssl_max_protocol_version);
209
210 if (ssl_ver_max == -1)
211 {
212 ereport(isServerStart ? FATAL : LOG,
213 /*- translator: first %s is a GUC option name, second %s is its value */
214 (errmsg("\"%s\" setting \"%s\" not supported by this build",
215 "ssl_max_protocol_version",
216 GetConfigOption("ssl_max_protocol_version",
217 false, false))));
218 goto error;
219 }
220
221 if (!SSL_CTX_set_max_proto_version(context, ssl_ver_max))
222 {
223 ereport(isServerStart ? FATAL : LOG,
224 (errmsg("could not set maximum SSL protocol version")));
225 goto error;
226 }
227 }
228
229 /* Check compatibility of min/max protocols */
230 if (ssl_min_protocol_version &&
231 ssl_max_protocol_version)
232 {
233 /*
234 * No need to check for invalid values (-1) for each protocol number
235 * as the code above would have already generated an error.
236 */
237 if (ssl_ver_min > ssl_ver_max)
238 {
239 ereport(isServerStart ? FATAL : LOG,
240 (errcode(ERRCODE_CONFIG_FILE_ERROR),
241 errmsg("could not set SSL protocol version range"),
242 errdetail("\"%s\" cannot be higher than \"%s\"",
243 "ssl_min_protocol_version",
244 "ssl_max_protocol_version")));
245 goto error;
246 }
247 }
248
249 /*
250 * Disallow SSL session tickets. OpenSSL use both stateful and stateless
251 * tickets for TLSv1.3, and stateless ticket for TLSv1.2. SSL_OP_NO_TICKET
252 * is available since 0.9.8f but only turns off stateless tickets. In
253 * order to turn off stateful tickets we need SSL_CTX_set_num_tickets,
254 * which is available since OpenSSL 1.1.1. LibreSSL 3.5.4 (from OpenBSD
255 * 7.1) introduced this API for compatibility, but doesn't support session
256 * tickets at all so it's a no-op there.
257 */
258#ifdef HAVE_SSL_CTX_SET_NUM_TICKETS
259 SSL_CTX_set_num_tickets(context, 0);
260#endif
261 SSL_CTX_set_options(context, SSL_OP_NO_TICKET);
262
263 /* disallow SSL session caching, too */
264 SSL_CTX_set_session_cache_mode(context, SSL_SESS_CACHE_OFF);
265
266 /* disallow SSL compression */
267 SSL_CTX_set_options(context, SSL_OP_NO_COMPRESSION);
268
269 /*
270 * Disallow SSL renegotiation. This concerns only TLSv1.2 and older
271 * protocol versions, as TLSv1.3 has no support for renegotiation.
272 * SSL_OP_NO_RENEGOTIATION is available in OpenSSL since 1.1.0h (via a
273 * backport from 1.1.1). SSL_OP_NO_CLIENT_RENEGOTIATION is available in
274 * LibreSSL since 2.5.1 disallowing all client-initiated renegotiation
275 * (this is usually on by default).
276 */
277#ifdef SSL_OP_NO_RENEGOTIATION
278 SSL_CTX_set_options(context, SSL_OP_NO_RENEGOTIATION);
279#endif
280#ifdef SSL_OP_NO_CLIENT_RENEGOTIATION
281 SSL_CTX_set_options(context, SSL_OP_NO_CLIENT_RENEGOTIATION);
282#endif
283
284 /* set up ephemeral DH and ECDH keys */
285 if (!initialize_dh(context, isServerStart))
286 goto error;
287 if (!initialize_ecdh(context, isServerStart))
288 goto error;
289
290 /* set up the allowed cipher list for TLSv1.2 and below */
291 if (SSL_CTX_set_cipher_list(context, SSLCipherList) != 1)
292 {
293 ereport(isServerStart ? FATAL : LOG,
294 (errcode(ERRCODE_CONFIG_FILE_ERROR),
295 errmsg("could not set the TLSv1.2 cipher list (no valid ciphers available)")));
296 goto error;
297 }
298
299 /*
300 * Set up the allowed cipher suites for TLSv1.3. If the GUC is an empty
301 * string we leave the allowed suites to be the OpenSSL default value.
302 */
303 if (SSLCipherSuites[0])
304 {
305 /* set up the allowed cipher suites */
306 if (SSL_CTX_set_ciphersuites(context, SSLCipherSuites) != 1)
307 {
308 ereport(isServerStart ? FATAL : LOG,
309 (errcode(ERRCODE_CONFIG_FILE_ERROR),
310 errmsg("could not set the TLSv1.3 cipher suites (no valid ciphers available)")));
311 goto error;
312 }
313 }
314
315 /* Let server choose order */
316 if (SSLPreferServerCiphers)
317 SSL_CTX_set_options(context, SSL_OP_CIPHER_SERVER_PREFERENCE);
318
319 /*
320 * Load CA store, so we can verify client certificates if needed.
321 */
322 if (ssl_ca_file[0])
323 {
324 STACK_OF(X509_NAME) * root_cert_list;
325
326 if (SSL_CTX_load_verify_locations(context, ssl_ca_file, NULL) != 1 ||
327 (root_cert_list = SSL_load_client_CA_file(ssl_ca_file)) == NULL)
328 {
329 ereport(isServerStart ? FATAL : LOG,
330 (errcode(ERRCODE_CONFIG_FILE_ERROR),
331 errmsg("could not load root certificate file \"%s\": %s",
332 ssl_ca_file, SSLerrmessage(ERR_get_error()))));
333 goto error;
334 }
335
336 /*
337 * Tell OpenSSL to send the list of root certs we trust to clients in
338 * CertificateRequests. This lets a client with a keystore select the
339 * appropriate client certificate to send to us. Also, this ensures
340 * that the SSL context will "own" the root_cert_list and remember to
341 * free it when no longer needed.
342 */
343 SSL_CTX_set_client_CA_list(context, root_cert_list);
344
345 /*
346 * Always ask for SSL client cert, but don't fail if it's not
347 * presented. We might fail such connections later, depending on what
348 * we find in pg_hba.conf.
349 */
350 SSL_CTX_set_verify(context,
351 (SSL_VERIFY_PEER |
352 SSL_VERIFY_CLIENT_ONCE),
353 verify_cb);
354 }
355
356 /*----------
357 * Load the Certificate Revocation List (CRL).
358 * http://searchsecurity.techtarget.com/sDefinition/0,,sid14_gci803160,00.html
359 *----------
360 */
361 if (ssl_crl_file[0] || ssl_crl_dir[0])
362 {
363 X509_STORE *cvstore = SSL_CTX_get_cert_store(context);
364
365 if (cvstore)
366 {
367 /* Set the flags to check against the complete CRL chain */
368 if (X509_STORE_load_locations(cvstore,
369 ssl_crl_file[0] ? ssl_crl_file : NULL,
370 ssl_crl_dir[0] ? ssl_crl_dir : NULL)
371 == 1)
372 {
373 X509_STORE_set_flags(cvstore,
374 X509_V_FLAG_CRL_CHECK | X509_V_FLAG_CRL_CHECK_ALL);
375 }
376 else if (ssl_crl_dir[0] == 0)
377 {
378 ereport(isServerStart ? FATAL : LOG,
379 (errcode(ERRCODE_CONFIG_FILE_ERROR),
380 errmsg("could not load SSL certificate revocation list file \"%s\": %s",
381 ssl_crl_file, SSLerrmessage(ERR_get_error()))));
382 goto error;
383 }
384 else if (ssl_crl_file[0] == 0)
385 {
386 ereport(isServerStart ? FATAL : LOG,
387 (errcode(ERRCODE_CONFIG_FILE_ERROR),
388 errmsg("could not load SSL certificate revocation list directory \"%s\": %s",
389 ssl_crl_dir, SSLerrmessage(ERR_get_error()))));
390 goto error;
391 }
392 else
393 {
394 ereport(isServerStart ? FATAL : LOG,
395 (errcode(ERRCODE_CONFIG_FILE_ERROR),
396 errmsg("could not load SSL certificate revocation list file \"%s\" or directory \"%s\": %s",
397 ssl_crl_file, ssl_crl_dir,
398 SSLerrmessage(ERR_get_error()))));
399 goto error;
400 }
401 }
402 }
403
404 /*
405 * Success! Replace any existing SSL_context.
406 */
407 if (SSL_context)
408 SSL_CTX_free(SSL_context);
409
410 SSL_context = context;
411
412 /*
413 * Set flag to remember whether CA store has been loaded into SSL_context.
414 */
415 if (ssl_ca_file[0])
416 ssl_loaded_verify_locations = true;
417 else
418 ssl_loaded_verify_locations = false;
419
420 return 0;
421
422 /* Clean up by releasing working context. */
423error:
424 if (context)
425 SSL_CTX_free(context);
426 return -1;
427}
428
429void
430 be_tls_destroy(void)
431{
432 if (SSL_context)
433 SSL_CTX_free(SSL_context);
434 SSL_context = NULL;
435 ssl_loaded_verify_locations = false;
436}
437
438int
439 be_tls_open_server(Port *port)
440{
441 int r;
442 int err;
443 int waitfor;
444 unsigned long ecode;
445 bool give_proto_hint;
446
447 Assert(!port->ssl);
448 Assert(!port->peer);
449
450 if (!SSL_context)
451 {
452 ereport(COMMERROR,
453 (errcode(ERRCODE_PROTOCOL_VIOLATION),
454 errmsg("could not initialize SSL connection: SSL context not set up")));
455 return -1;
456 }
457
458 /* set up debugging/info callback */
459 SSL_CTX_set_info_callback(SSL_context, info_cb);
460
461 /* enable ALPN */
462 SSL_CTX_set_alpn_select_cb(SSL_context, alpn_cb, port);
463
464 if (!(port->ssl = SSL_new(SSL_context)))
465 {
466 ereport(COMMERROR,
467 (errcode(ERRCODE_PROTOCOL_VIOLATION),
468 errmsg("could not initialize SSL connection: %s",
469 SSLerrmessage(ERR_get_error()))));
470 return -1;
471 }
472 if (!ssl_set_port_bio(port))
473 {
474 ereport(COMMERROR,
475 (errcode(ERRCODE_PROTOCOL_VIOLATION),
476 errmsg("could not set SSL socket: %s",
477 SSLerrmessage(ERR_get_error()))));
478 return -1;
479 }
480 port->ssl_in_use = true;
481
482aloop:
483
484 /*
485 * Prepare to call SSL_get_error() by clearing thread's OpenSSL error
486 * queue. In general, the current thread's error queue must be empty
487 * before the TLS/SSL I/O operation is attempted, or SSL_get_error() will
488 * not work reliably. An extension may have failed to clear the
489 * per-thread error queue following another call to an OpenSSL I/O
490 * routine.
491 */
492 errno = 0;
493 ERR_clear_error();
494 r = SSL_accept(port->ssl);
495 if (r <= 0)
496 {
497 err = SSL_get_error(port->ssl, r);
498
499 /*
500 * Other clients of OpenSSL in the backend may fail to call
501 * ERR_get_error(), but we always do, so as to not cause problems for
502 * OpenSSL clients that don't call ERR_clear_error() defensively. Be
503 * sure that this happens by calling now. SSL_get_error() relies on
504 * the OpenSSL per-thread error queue being intact, so this is the
505 * earliest possible point ERR_get_error() may be called.
506 */
507 ecode = ERR_get_error();
508 switch (err)
509 {
510 case SSL_ERROR_WANT_READ:
511 case SSL_ERROR_WANT_WRITE:
512 /* not allowed during connection establishment */
513 Assert(!port->noblock);
514
515 /*
516 * No need to care about timeouts/interrupts here. At this
517 * point authentication_timeout still employs
518 * StartupPacketTimeoutHandler() which directly exits.
519 */
520 if (err == SSL_ERROR_WANT_READ)
521 waitfor = WL_SOCKET_READABLE | WL_EXIT_ON_PM_DEATH;
522 else
523 waitfor = WL_SOCKET_WRITEABLE | WL_EXIT_ON_PM_DEATH;
524
525 (void) WaitLatchOrSocket(NULL, waitfor, port->sock, 0,
526 WAIT_EVENT_SSL_OPEN_SERVER);
527 goto aloop;
528 case SSL_ERROR_SYSCALL:
529 if (r < 0 && errno != 0)
530 ereport(COMMERROR,
531 (errcode_for_socket_access(),
532 errmsg("could not accept SSL connection: %m")));
533 else
534 ereport(COMMERROR,
535 (errcode(ERRCODE_PROTOCOL_VIOLATION),
536 errmsg("could not accept SSL connection: EOF detected")));
537 break;
538 case SSL_ERROR_SSL:
539 switch (ERR_GET_REASON(ecode))
540 {
541 /*
542 * UNSUPPORTED_PROTOCOL, WRONG_VERSION_NUMBER, and
543 * TLSV1_ALERT_PROTOCOL_VERSION have been observed
544 * when trying to communicate with an old OpenSSL
545 * library, or when the client and server specify
546 * disjoint protocol ranges. NO_PROTOCOLS_AVAILABLE
547 * occurs if there's a local misconfiguration (which
548 * can happen despite our checks, if openssl.cnf
549 * injects a limit we didn't account for). It's not
550 * very clear what would make OpenSSL return the other
551 * codes listed here, but a hint about protocol
552 * versions seems like it's appropriate for all.
553 */
554 case SSL_R_NO_PROTOCOLS_AVAILABLE:
555 case SSL_R_UNSUPPORTED_PROTOCOL:
556 case SSL_R_BAD_PROTOCOL_VERSION_NUMBER:
557 case SSL_R_UNKNOWN_PROTOCOL:
558 case SSL_R_UNKNOWN_SSL_VERSION:
559 case SSL_R_UNSUPPORTED_SSL_VERSION:
560 case SSL_R_WRONG_SSL_VERSION:
561 case SSL_R_WRONG_VERSION_NUMBER:
562 case SSL_R_TLSV1_ALERT_PROTOCOL_VERSION:
563#ifdef SSL_R_VERSION_TOO_HIGH
564 case SSL_R_VERSION_TOO_HIGH:
565#endif
566#ifdef SSL_R_VERSION_TOO_LOW
567 case SSL_R_VERSION_TOO_LOW:
568#endif
569 give_proto_hint = true;
570 break;
571 default:
572 give_proto_hint = false;
573 break;
574 }
575 ereport(COMMERROR,
576 (errcode(ERRCODE_PROTOCOL_VIOLATION),
577 errmsg("could not accept SSL connection: %s",
578 SSLerrmessage(ecode)),
579 cert_errdetail ? errdetail_internal("%s", cert_errdetail) : 0,
580 give_proto_hint ?
581 errhint("This may indicate that the client does not support any SSL protocol version between %s and %s.",
582 ssl_min_protocol_version ?
583 ssl_protocol_version_to_string(ssl_min_protocol_version) :
584 MIN_OPENSSL_TLS_VERSION,
585 ssl_max_protocol_version ?
586 ssl_protocol_version_to_string(ssl_max_protocol_version) :
587 MAX_OPENSSL_TLS_VERSION) : 0));
588 cert_errdetail = NULL;
589 break;
590 case SSL_ERROR_ZERO_RETURN:
591 ereport(COMMERROR,
592 (errcode(ERRCODE_PROTOCOL_VIOLATION),
593 errmsg("could not accept SSL connection: EOF detected")));
594 break;
595 default:
596 ereport(COMMERROR,
597 (errcode(ERRCODE_PROTOCOL_VIOLATION),
598 errmsg("unrecognized SSL error code: %d",
599 err)));
600 break;
601 }
602 return -1;
603 }
604
605 /* Get the protocol selected by ALPN */
606 port->alpn_used = false;
607 {
608 const unsigned char *selected;
609 unsigned int len;
610
611 SSL_get0_alpn_selected(port->ssl, &selected, &len);
612
613 /* If ALPN is used, check that we negotiated the expected protocol */
614 if (selected != NULL)
615 {
616 if (len == strlen(PG_ALPN_PROTOCOL) &&
617 memcmp(selected, PG_ALPN_PROTOCOL, strlen(PG_ALPN_PROTOCOL)) == 0)
618 {
619 port->alpn_used = true;
620 }
621 else
622 {
623 /* shouldn't happen */
624 ereport(COMMERROR,
625 (errcode(ERRCODE_PROTOCOL_VIOLATION),
626 errmsg("received SSL connection request with unexpected ALPN protocol")));
627 }
628 }
629 }
630
631 /* Get client certificate, if available. */
632 port->peer = SSL_get_peer_certificate(port->ssl);
633
634 /* and extract the Common Name and Distinguished Name from it. */
635 port->peer_cn = NULL;
636 port->peer_dn = NULL;
637 port->peer_cert_valid = false;
638 if (port->peer != NULL)
639 {
640 int len;
641 X509_NAME *x509name = X509_get_subject_name(port->peer);
642 char *peer_dn;
643 BIO *bio = NULL;
644 BUF_MEM *bio_buf = NULL;
645
646 len = X509_NAME_get_text_by_NID(x509name, NID_commonName, NULL, 0);
647 if (len != -1)
648 {
649 char *peer_cn;
650
651 peer_cn = MemoryContextAlloc(TopMemoryContext, len + 1);
652 r = X509_NAME_get_text_by_NID(x509name, NID_commonName, peer_cn,
653 len + 1);
654 peer_cn[len] = '0円';
655 if (r != len)
656 {
657 /* shouldn't happen */
658 pfree(peer_cn);
659 return -1;
660 }
661
662 /*
663 * Reject embedded NULLs in certificate common name to prevent
664 * attacks like CVE-2009-4034.
665 */
666 if (len != strlen(peer_cn))
667 {
668 ereport(COMMERROR,
669 (errcode(ERRCODE_PROTOCOL_VIOLATION),
670 errmsg("SSL certificate's common name contains embedded null")));
671 pfree(peer_cn);
672 return -1;
673 }
674
675 port->peer_cn = peer_cn;
676 }
677
678 bio = BIO_new(BIO_s_mem());
679 if (!bio)
680 {
681 if (port->peer_cn != NULL)
682 {
683 pfree(port->peer_cn);
684 port->peer_cn = NULL;
685 }
686 return -1;
687 }
688
689 /*
690 * RFC2253 is the closest thing to an accepted standard format for
691 * DNs. We have documented how to produce this format from a
692 * certificate. It uses commas instead of slashes for delimiters,
693 * which make regular expression matching a bit easier. Also note that
694 * it prints the Subject fields in reverse order.
695 */
696 if (X509_NAME_print_ex(bio, x509name, 0, XN_FLAG_RFC2253) == -1 ||
697 BIO_get_mem_ptr(bio, &bio_buf) <= 0)
698 {
699 BIO_free(bio);
700 if (port->peer_cn != NULL)
701 {
702 pfree(port->peer_cn);
703 port->peer_cn = NULL;
704 }
705 return -1;
706 }
707 peer_dn = MemoryContextAlloc(TopMemoryContext, bio_buf->length + 1);
708 memcpy(peer_dn, bio_buf->data, bio_buf->length);
709 len = bio_buf->length;
710 BIO_free(bio);
711 peer_dn[len] = '0円';
712 if (len != strlen(peer_dn))
713 {
714 ereport(COMMERROR,
715 (errcode(ERRCODE_PROTOCOL_VIOLATION),
716 errmsg("SSL certificate's distinguished name contains embedded null")));
717 pfree(peer_dn);
718 if (port->peer_cn != NULL)
719 {
720 pfree(port->peer_cn);
721 port->peer_cn = NULL;
722 }
723 return -1;
724 }
725
726 port->peer_dn = peer_dn;
727
728 port->peer_cert_valid = true;
729 }
730
731 return 0;
732}
733
734void
735 be_tls_close(Port *port)
736{
737 if (port->ssl)
738 {
739 SSL_shutdown(port->ssl);
740 SSL_free(port->ssl);
741 port->ssl = NULL;
742 port->ssl_in_use = false;
743 }
744
745 if (port->peer)
746 {
747 X509_free(port->peer);
748 port->peer = NULL;
749 }
750
751 if (port->peer_cn)
752 {
753 pfree(port->peer_cn);
754 port->peer_cn = NULL;
755 }
756
757 if (port->peer_dn)
758 {
759 pfree(port->peer_dn);
760 port->peer_dn = NULL;
761 }
762}
763
764ssize_t
765 be_tls_read(Port *port, void *ptr, size_t len, int *waitfor)
766{
767 ssize_t n;
768 int err;
769 unsigned long ecode;
770
771 errno = 0;
772 ERR_clear_error();
773 n = SSL_read(port->ssl, ptr, len);
774 err = SSL_get_error(port->ssl, n);
775 ecode = (err != SSL_ERROR_NONE || n < 0) ? ERR_get_error() : 0;
776 switch (err)
777 {
778 case SSL_ERROR_NONE:
779 /* a-ok */
780 break;
781 case SSL_ERROR_WANT_READ:
782 *waitfor = WL_SOCKET_READABLE;
783 errno = EWOULDBLOCK;
784 n = -1;
785 break;
786 case SSL_ERROR_WANT_WRITE:
787 *waitfor = WL_SOCKET_WRITEABLE;
788 errno = EWOULDBLOCK;
789 n = -1;
790 break;
791 case SSL_ERROR_SYSCALL:
792 /* leave it to caller to ereport the value of errno */
793 if (n != -1 || errno == 0)
794 {
795 errno = ECONNRESET;
796 n = -1;
797 }
798 break;
799 case SSL_ERROR_SSL:
800 ereport(COMMERROR,
801 (errcode(ERRCODE_PROTOCOL_VIOLATION),
802 errmsg("SSL error: %s", SSLerrmessage(ecode))));
803 errno = ECONNRESET;
804 n = -1;
805 break;
806 case SSL_ERROR_ZERO_RETURN:
807 /* connection was cleanly shut down by peer */
808 n = 0;
809 break;
810 default:
811 ereport(COMMERROR,
812 (errcode(ERRCODE_PROTOCOL_VIOLATION),
813 errmsg("unrecognized SSL error code: %d",
814 err)));
815 errno = ECONNRESET;
816 n = -1;
817 break;
818 }
819
820 return n;
821}
822
823ssize_t
824 be_tls_write(Port *port, const void *ptr, size_t len, int *waitfor)
825{
826 ssize_t n;
827 int err;
828 unsigned long ecode;
829
830 errno = 0;
831 ERR_clear_error();
832 n = SSL_write(port->ssl, ptr, len);
833 err = SSL_get_error(port->ssl, n);
834 ecode = (err != SSL_ERROR_NONE || n < 0) ? ERR_get_error() : 0;
835 switch (err)
836 {
837 case SSL_ERROR_NONE:
838 /* a-ok */
839 break;
840 case SSL_ERROR_WANT_READ:
841 *waitfor = WL_SOCKET_READABLE;
842 errno = EWOULDBLOCK;
843 n = -1;
844 break;
845 case SSL_ERROR_WANT_WRITE:
846 *waitfor = WL_SOCKET_WRITEABLE;
847 errno = EWOULDBLOCK;
848 n = -1;
849 break;
850 case SSL_ERROR_SYSCALL:
851
852 /*
853 * Leave it to caller to ereport the value of errno. However, if
854 * errno is still zero then assume it's a read EOF situation, and
855 * report ECONNRESET. (This seems possible because SSL_write can
856 * also do reads.)
857 */
858 if (n != -1 || errno == 0)
859 {
860 errno = ECONNRESET;
861 n = -1;
862 }
863 break;
864 case SSL_ERROR_SSL:
865 ereport(COMMERROR,
866 (errcode(ERRCODE_PROTOCOL_VIOLATION),
867 errmsg("SSL error: %s", SSLerrmessage(ecode))));
868 errno = ECONNRESET;
869 n = -1;
870 break;
871 case SSL_ERROR_ZERO_RETURN:
872
873 /*
874 * the SSL connection was closed, leave it to the caller to
875 * ereport it
876 */
877 errno = ECONNRESET;
878 n = -1;
879 break;
880 default:
881 ereport(COMMERROR,
882 (errcode(ERRCODE_PROTOCOL_VIOLATION),
883 errmsg("unrecognized SSL error code: %d",
884 err)));
885 errno = ECONNRESET;
886 n = -1;
887 break;
888 }
889
890 return n;
891}
892
893/* ------------------------------------------------------------ */
894/* Internal functions */
895/* ------------------------------------------------------------ */
896
897/*
898 * Private substitute BIO: this does the sending and receiving using send() and
899 * recv() instead. This is so that we can enable and disable interrupts
900 * just while calling recv(). We cannot have interrupts occurring while
901 * the bulk of OpenSSL runs, because it uses malloc() and possibly other
902 * non-reentrant libc facilities. We also need to call send() and recv()
903 * directly so it gets passed through the socket/signals layer on Win32.
904 *
905 * These functions are closely modelled on the standard socket BIO in OpenSSL;
906 * see sock_read() and sock_write() in OpenSSL's crypto/bio/bss_sock.c.
907 */
908
909 static BIO_METHOD *port_bio_method_ptr = NULL;
910
911static int
912 port_bio_read(BIO *h, char *buf, int size)
913{
914 int res = 0;
915 Port *port = (Port *) BIO_get_data(h);
916
917 if (buf != NULL)
918 {
919 res = secure_raw_read(port, buf, size);
920 BIO_clear_retry_flags(h);
921 port->last_read_was_eof = res == 0;
922 if (res <= 0)
923 {
924 /* If we were interrupted, tell caller to retry */
925 if (errno == EINTR || errno == EWOULDBLOCK || errno == EAGAIN)
926 {
927 BIO_set_retry_read(h);
928 }
929 }
930 }
931
932 return res;
933}
934
935static int
936 port_bio_write(BIO *h, const char *buf, int size)
937{
938 int res = 0;
939
940 res = secure_raw_write(((Port *) BIO_get_data(h)), buf, size);
941 BIO_clear_retry_flags(h);
942 if (res <= 0)
943 {
944 /* If we were interrupted, tell caller to retry */
945 if (errno == EINTR || errno == EWOULDBLOCK || errno == EAGAIN)
946 {
947 BIO_set_retry_write(h);
948 }
949 }
950
951 return res;
952}
953
954static long
955 port_bio_ctrl(BIO *h, int cmd, long num, void *ptr)
956{
957 long res;
958 Port *port = (Port *) BIO_get_data(h);
959
960 switch (cmd)
961 {
962 case BIO_CTRL_EOF:
963
964 /*
965 * This should not be needed. port_bio_read already has a way to
966 * signal EOF to OpenSSL. However, OpenSSL made an undocumented,
967 * backwards-incompatible change and now expects EOF via BIO_ctrl.
968 * See https://github.com/openssl/openssl/issues/8208
969 */
970 res = port->last_read_was_eof;
971 break;
972 case BIO_CTRL_FLUSH:
973 /* libssl expects all BIOs to support BIO_flush. */
974 res = 1;
975 break;
976 default:
977 res = 0;
978 break;
979 }
980
981 return res;
982}
983
984static BIO_METHOD *
985 port_bio_method(void)
986{
987 if (!port_bio_method_ptr)
988 {
989 int my_bio_index;
990
991 my_bio_index = BIO_get_new_index();
992 if (my_bio_index == -1)
993 return NULL;
994 my_bio_index |= BIO_TYPE_SOURCE_SINK;
995 port_bio_method_ptr = BIO_meth_new(my_bio_index, "PostgreSQL backend socket");
996 if (!port_bio_method_ptr)
997 return NULL;
998 if (!BIO_meth_set_write(port_bio_method_ptr, port_bio_write) ||
999 !BIO_meth_set_read(port_bio_method_ptr, port_bio_read) ||
1000 !BIO_meth_set_ctrl(port_bio_method_ptr, port_bio_ctrl))
1001 {
1002 BIO_meth_free(port_bio_method_ptr);
1003 port_bio_method_ptr = NULL;
1004 return NULL;
1005 }
1006 }
1007 return port_bio_method_ptr;
1008}
1009
1010static int
1011 ssl_set_port_bio(Port *port)
1012{
1013 BIO *bio;
1014 BIO_METHOD *bio_method;
1015
1016 bio_method = port_bio_method();
1017 if (bio_method == NULL)
1018 return 0;
1019
1020 bio = BIO_new(bio_method);
1021 if (bio == NULL)
1022 return 0;
1023
1024 BIO_set_data(bio, port);
1025 BIO_set_init(bio, 1);
1026
1027 SSL_set_bio(port->ssl, bio, bio);
1028 return 1;
1029}
1030
1031/*
1032 * Load precomputed DH parameters.
1033 *
1034 * To prevent "downgrade" attacks, we perform a number of checks
1035 * to verify that the DBA-generated DH parameters file contains
1036 * what we expect it to contain.
1037 */
1038static DH *
1039 load_dh_file(char *filename, bool isServerStart)
1040{
1041 FILE *fp;
1042 DH *dh = NULL;
1043 int codes;
1044
1045 /* attempt to open file. It's not an error if it doesn't exist. */
1046 if ((fp = AllocateFile(filename, "r")) == NULL)
1047 {
1048 ereport(isServerStart ? FATAL : LOG,
1049 (errcode_for_file_access(),
1050 errmsg("could not open DH parameters file \"%s\": %m",
1051 filename)));
1052 return NULL;
1053 }
1054
1055 dh = PEM_read_DHparams(fp, NULL, NULL, NULL);
1056 FreeFile(fp);
1057
1058 if (dh == NULL)
1059 {
1060 ereport(isServerStart ? FATAL : LOG,
1061 (errcode(ERRCODE_CONFIG_FILE_ERROR),
1062 errmsg("could not load DH parameters file: %s",
1063 SSLerrmessage(ERR_get_error()))));
1064 return NULL;
1065 }
1066
1067 /* make sure the DH parameters are usable */
1068 if (DH_check(dh, &codes) == 0)
1069 {
1070 ereport(isServerStart ? FATAL : LOG,
1071 (errcode(ERRCODE_CONFIG_FILE_ERROR),
1072 errmsg("invalid DH parameters: %s",
1073 SSLerrmessage(ERR_get_error()))));
1074 DH_free(dh);
1075 return NULL;
1076 }
1077 if (codes & DH_CHECK_P_NOT_PRIME)
1078 {
1079 ereport(isServerStart ? FATAL : LOG,
1080 (errcode(ERRCODE_CONFIG_FILE_ERROR),
1081 errmsg("invalid DH parameters: p is not prime")));
1082 DH_free(dh);
1083 return NULL;
1084 }
1085 if ((codes & DH_NOT_SUITABLE_GENERATOR) &&
1086 (codes & DH_CHECK_P_NOT_SAFE_PRIME))
1087 {
1088 ereport(isServerStart ? FATAL : LOG,
1089 (errcode(ERRCODE_CONFIG_FILE_ERROR),
1090 errmsg("invalid DH parameters: neither suitable generator or safe prime")));
1091 DH_free(dh);
1092 return NULL;
1093 }
1094
1095 return dh;
1096}
1097
1098/*
1099 * Load hardcoded DH parameters.
1100 *
1101 * If DH parameters cannot be loaded from a specified file, we can load
1102 * the hardcoded DH parameters supplied with the backend to prevent
1103 * problems.
1104 */
1105static DH *
1106 load_dh_buffer(const char *buffer, size_t len)
1107{
1108 BIO *bio;
1109 DH *dh = NULL;
1110
1111 bio = BIO_new_mem_buf(buffer, len);
1112 if (bio == NULL)
1113 return NULL;
1114 dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
1115 if (dh == NULL)
1116 ereport(DEBUG2,
1117 (errmsg_internal("DH load buffer: %s",
1118 SSLerrmessage(ERR_get_error()))));
1119 BIO_free(bio);
1120
1121 return dh;
1122}
1123
1124/*
1125 * Passphrase collection callback using ssl_passphrase_command
1126 */
1127static int
1128 ssl_external_passwd_cb(char *buf, int size, int rwflag, void *userdata)
1129{
1130 /* same prompt as OpenSSL uses internally */
1131 const char *prompt = "Enter PEM pass phrase:";
1132
1133 Assert(rwflag == 0);
1134
1135 return run_ssl_passphrase_command(prompt, ssl_is_server_start, buf, size);
1136}
1137
1138/*
1139 * Dummy passphrase callback
1140 *
1141 * If OpenSSL is told to use a passphrase-protected server key, by default
1142 * it will issue a prompt on /dev/tty and try to read a key from there.
1143 * That's no good during a postmaster SIGHUP cycle, not to mention SSL context
1144 * reload in an EXEC_BACKEND postmaster child. So override it with this dummy
1145 * function that just returns an empty passphrase, guaranteeing failure.
1146 */
1147static int
1148 dummy_ssl_passwd_cb(char *buf, int size, int rwflag, void *userdata)
1149{
1150 /* Set flag to change the error message we'll report */
1151 dummy_ssl_passwd_cb_called = true;
1152 /* And return empty string */
1153 Assert(size > 0);
1154 buf[0] = '0円';
1155 return 0;
1156}
1157
1158/*
1159 * Examines the provided certificate name, and if it's too long to log or
1160 * contains unprintable ASCII, escapes and truncates it. The return value is
1161 * always a new palloc'd string. (The input string is still modified in place,
1162 * for ease of implementation.)
1163 */
1164static char *
1165 prepare_cert_name(char *name)
1166{
1167 size_t namelen = strlen(name);
1168 char *truncated = name;
1169
1170 /*
1171 * Common Names are 64 chars max, so for a common case where the CN is the
1172 * last field, we can still print the longest possible CN with a
1173 * 7-character prefix (".../CN=[64 chars]"), for a reasonable limit of 71
1174 * characters.
1175 */
1176#define MAXLEN 71
1177
1178 if (namelen > MAXLEN)
1179 {
1180 /*
1181 * Keep the end of the name, not the beginning, since the most
1182 * specific field is likely to give users the most information.
1183 */
1184 truncated = name + namelen - MAXLEN;
1185 truncated[0] = truncated[1] = truncated[2] = '.';
1186 namelen = MAXLEN;
1187 }
1188
1189#undef MAXLEN
1190
1191 return pg_clean_ascii(truncated, 0);
1192}
1193
1194/*
1195 * Certificate verification callback
1196 *
1197 * This callback allows us to examine intermediate problems during
1198 * verification, for later logging.
1199 *
1200 * This callback also allows us to override the default acceptance
1201 * criteria (e.g., accepting self-signed or expired certs), but
1202 * for now we accept the default checks.
1203 */
1204static int
1205 verify_cb(int ok, X509_STORE_CTX *ctx)
1206{
1207 int depth;
1208 int errcode;
1209 const char *errstring;
1210 StringInfoData str;
1211 X509 *cert;
1212
1213 if (ok)
1214 {
1215 /* Nothing to do for the successful case. */
1216 return ok;
1217 }
1218
1219 /* Pull all the information we have on the verification failure. */
1220 depth = X509_STORE_CTX_get_error_depth(ctx);
1221 errcode = X509_STORE_CTX_get_error(ctx);
1222 errstring = X509_verify_cert_error_string(errcode);
1223
1224 initStringInfo(&str);
1225 appendStringInfo(&str,
1226 _("Client certificate verification failed at depth %d: %s."),
1227 depth, errstring);
1228
1229 cert = X509_STORE_CTX_get_current_cert(ctx);
1230 if (cert)
1231 {
1232 char *subject,
1233 *issuer;
1234 char *sub_prepared,
1235 *iss_prepared;
1236 char *serialno;
1237 ASN1_INTEGER *sn;
1238 BIGNUM *b;
1239
1240 /*
1241 * Get the Subject and Issuer for logging, but don't let maliciously
1242 * huge certs flood the logs, and don't reflect non-ASCII bytes into
1243 * it either.
1244 */
1245 subject = X509_NAME_to_cstring(X509_get_subject_name(cert));
1246 sub_prepared = prepare_cert_name(subject);
1247 pfree(subject);
1248
1249 issuer = X509_NAME_to_cstring(X509_get_issuer_name(cert));
1250 iss_prepared = prepare_cert_name(issuer);
1251 pfree(issuer);
1252
1253 /*
1254 * Pull the serial number, too, in case a Subject is still ambiguous.
1255 * This mirrors be_tls_get_peer_serial().
1256 */
1257 sn = X509_get_serialNumber(cert);
1258 b = ASN1_INTEGER_to_BN(sn, NULL);
1259 serialno = BN_bn2dec(b);
1260
1261 appendStringInfoChar(&str, '\n');
1262 appendStringInfo(&str,
1263 _("Failed certificate data (unverified): subject \"%s\", serial number %s, issuer \"%s\"."),
1264 sub_prepared, serialno ? serialno : _("unknown"),
1265 iss_prepared);
1266
1267 BN_free(b);
1268 OPENSSL_free(serialno);
1269 pfree(iss_prepared);
1270 pfree(sub_prepared);
1271 }
1272
1273 /* Store our detail message to be logged later. */
1274 cert_errdetail = str.data;
1275
1276 return ok;
1277}
1278
1279/*
1280 * This callback is used to copy SSL information messages
1281 * into the PostgreSQL log.
1282 */
1283static void
1284 info_cb(const SSL *ssl, int type, int args)
1285{
1286 const char *desc;
1287
1288 desc = SSL_state_string_long(ssl);
1289
1290 switch (type)
1291 {
1292 case SSL_CB_HANDSHAKE_START:
1293 ereport(DEBUG4,
1294 (errmsg_internal("SSL: handshake start: \"%s\"", desc)));
1295 break;
1296 case SSL_CB_HANDSHAKE_DONE:
1297 ereport(DEBUG4,
1298 (errmsg_internal("SSL: handshake done: \"%s\"", desc)));
1299 break;
1300 case SSL_CB_ACCEPT_LOOP:
1301 ereport(DEBUG4,
1302 (errmsg_internal("SSL: accept loop: \"%s\"", desc)));
1303 break;
1304 case SSL_CB_ACCEPT_EXIT:
1305 ereport(DEBUG4,
1306 (errmsg_internal("SSL: accept exit (%d): \"%s\"", args, desc)));
1307 break;
1308 case SSL_CB_CONNECT_LOOP:
1309 ereport(DEBUG4,
1310 (errmsg_internal("SSL: connect loop: \"%s\"", desc)));
1311 break;
1312 case SSL_CB_CONNECT_EXIT:
1313 ereport(DEBUG4,
1314 (errmsg_internal("SSL: connect exit (%d): \"%s\"", args, desc)));
1315 break;
1316 case SSL_CB_READ_ALERT:
1317 ereport(DEBUG4,
1318 (errmsg_internal("SSL: read alert (0x%04x): \"%s\"", args, desc)));
1319 break;
1320 case SSL_CB_WRITE_ALERT:
1321 ereport(DEBUG4,
1322 (errmsg_internal("SSL: write alert (0x%04x): \"%s\"", args, desc)));
1323 break;
1324 }
1325}
1326
1327/* See pqcomm.h comments on OpenSSL implementation of ALPN (RFC 7301) */
1328 static const unsigned char alpn_protos[] = PG_ALPN_PROTOCOL_VECTOR;
1329
1330/*
1331 * Server callback for ALPN negotiation. We use the standard "helper" function
1332 * even though currently we only accept one value.
1333 */
1334static int
1335 alpn_cb(SSL *ssl,
1336 const unsigned char **out,
1337 unsigned char *outlen,
1338 const unsigned char *in,
1339 unsigned int inlen,
1340 void *userdata)
1341{
1342 /*
1343 * Why does OpenSSL provide a helper function that requires a nonconst
1344 * vector when the callback is declared to take a const vector? What are
1345 * we to do with that?
1346 */
1347 int retval;
1348
1349 Assert(userdata != NULL);
1350 Assert(out != NULL);
1351 Assert(outlen != NULL);
1352 Assert(in != NULL);
1353
1354 retval = SSL_select_next_proto((unsigned char **) out, outlen,
1355 alpn_protos, sizeof(alpn_protos),
1356 in, inlen);
1357 if (*out == NULL || *outlen > sizeof(alpn_protos) || *outlen <= 0)
1358 return SSL_TLSEXT_ERR_NOACK; /* can't happen */
1359
1360 if (retval == OPENSSL_NPN_NEGOTIATED)
1361 return SSL_TLSEXT_ERR_OK;
1362 else
1363 {
1364 /*
1365 * The client doesn't support our protocol. Reject the connection
1366 * with TLS "no_application_protocol" alert, per RFC 7301.
1367 */
1368 return SSL_TLSEXT_ERR_ALERT_FATAL;
1369 }
1370}
1371
1372
1373/*
1374 * Set DH parameters for generating ephemeral DH keys. The
1375 * DH parameters can take a long time to compute, so they must be
1376 * precomputed.
1377 *
1378 * Since few sites will bother to create a parameter file, we also
1379 * provide a fallback to the parameters provided by the OpenSSL
1380 * project.
1381 *
1382 * These values can be static (once loaded or computed) since the
1383 * OpenSSL library can efficiently generate random keys from the
1384 * information provided.
1385 */
1386static bool
1387 initialize_dh(SSL_CTX *context, bool isServerStart)
1388{
1389 DH *dh = NULL;
1390
1391 SSL_CTX_set_options(context, SSL_OP_SINGLE_DH_USE);
1392
1393 if (ssl_dh_params_file[0])
1394 dh = load_dh_file(ssl_dh_params_file, isServerStart);
1395 if (!dh)
1396 dh = load_dh_buffer(FILE_DH2048, sizeof(FILE_DH2048));
1397 if (!dh)
1398 {
1399 ereport(isServerStart ? FATAL : LOG,
1400 (errcode(ERRCODE_CONFIG_FILE_ERROR),
1401 errmsg("DH: could not load DH parameters")));
1402 return false;
1403 }
1404
1405 if (SSL_CTX_set_tmp_dh(context, dh) != 1)
1406 {
1407 ereport(isServerStart ? FATAL : LOG,
1408 (errcode(ERRCODE_CONFIG_FILE_ERROR),
1409 errmsg("DH: could not set DH parameters: %s",
1410 SSLerrmessage(ERR_get_error()))));
1411 DH_free(dh);
1412 return false;
1413 }
1414
1415 DH_free(dh);
1416 return true;
1417}
1418
1419/*
1420 * Set ECDH parameters for generating ephemeral Elliptic Curve DH
1421 * keys. This is much simpler than the DH parameters, as we just
1422 * need to provide the name of the curve to OpenSSL.
1423 */
1424static bool
1425 initialize_ecdh(SSL_CTX *context, bool isServerStart)
1426{
1427#ifndef OPENSSL_NO_ECDH
1428 if (SSL_CTX_set1_groups_list(context, SSLECDHCurve) != 1)
1429 {
1430 /*
1431 * OpenSSL 3.3.0 introduced proper error messages for group parsing
1432 * errors, earlier versions returns "no SSL error reported" which is
1433 * far from helpful. For older versions, we replace with a better
1434 * error message. Injecting the error into the OpenSSL error queue
1435 * need APIs from OpenSSL 3.0.
1436 */
1437 ereport(isServerStart ? FATAL : LOG,
1438 errcode(ERRCODE_CONFIG_FILE_ERROR),
1439 errmsg("could not set group names specified in ssl_groups: %s",
1440 SSLerrmessageExt(ERR_get_error(),
1441 _("No valid groups found"))),
1442 errhint("Ensure that each group name is spelled correctly and supported by the installed version of OpenSSL."));
1443 return false;
1444 }
1445#endif
1446
1447 return true;
1448}
1449
1450/*
1451 * Obtain reason string for passed SSL errcode with replacement
1452 *
1453 * The error message supplied in replacement will be used in case the error
1454 * code from OpenSSL is 0, else the error message from SSLerrmessage() will
1455 * be returned.
1456 *
1457 * Not all versions of OpenSSL place an error on the queue even for failing
1458 * operations, which will yield "no SSL error reported" by SSLerrmessage. This
1459 * function can be used to ensure that a proper error message is displayed for
1460 * versions reporting no error, while using the OpenSSL error via SSLerrmessage
1461 * for versions where there is one.
1462 */
1463static const char *
1464 SSLerrmessageExt(unsigned long ecode, const char *replacement)
1465{
1466 if (ecode == 0)
1467 return replacement;
1468 else
1469 return SSLerrmessage(ecode);
1470}
1471
1472/*
1473 * Obtain reason string for passed SSL errcode
1474 *
1475 * ERR_get_error() is used by caller to get errcode to pass here.
1476 *
1477 * Some caution is needed here since ERR_reason_error_string will return NULL
1478 * if it doesn't recognize the error code, or (in OpenSSL >= 3) if the code
1479 * represents a system errno value. We don't want to return NULL ever.
1480 */
1481static const char *
1482 SSLerrmessage(unsigned long ecode)
1483{
1484 const char *errreason;
1485 static char errbuf[36];
1486
1487 if (ecode == 0)
1488 return _("no SSL error reported");
1489 errreason = ERR_reason_error_string(ecode);
1490 if (errreason != NULL)
1491 return errreason;
1492
1493 /*
1494 * In OpenSSL 3.0.0 and later, ERR_reason_error_string does not map system
1495 * errno values anymore. (See OpenSSL source code for the explanation.)
1496 * We can cover that shortcoming with this bit of code. Older OpenSSL
1497 * versions don't have the ERR_SYSTEM_ERROR macro, but that's okay because
1498 * they don't have the shortcoming either.
1499 */
1500#ifdef ERR_SYSTEM_ERROR
1501 if (ERR_SYSTEM_ERROR(ecode))
1502 return strerror(ERR_GET_REASON(ecode));
1503#endif
1504
1505 /* No choice but to report the numeric ecode */
1506 snprintf(errbuf, sizeof(errbuf), _("SSL error code %lu"), ecode);
1507 return errbuf;
1508}
1509
1510int
1511 be_tls_get_cipher_bits(Port *port)
1512{
1513 int bits;
1514
1515 if (port->ssl)
1516 {
1517 SSL_get_cipher_bits(port->ssl, &bits);
1518 return bits;
1519 }
1520 else
1521 return 0;
1522}
1523
1524const char *
1525 be_tls_get_version(Port *port)
1526{
1527 if (port->ssl)
1528 return SSL_get_version(port->ssl);
1529 else
1530 return NULL;
1531}
1532
1533const char *
1534 be_tls_get_cipher(Port *port)
1535{
1536 if (port->ssl)
1537 return SSL_get_cipher(port->ssl);
1538 else
1539 return NULL;
1540}
1541
1542void
1543 be_tls_get_peer_subject_name(Port *port, char *ptr, size_t len)
1544{
1545 if (port->peer)
1546 strlcpy(ptr, X509_NAME_to_cstring(X509_get_subject_name(port->peer)), len);
1547 else
1548 ptr[0] = '0円';
1549}
1550
1551void
1552 be_tls_get_peer_issuer_name(Port *port, char *ptr, size_t len)
1553{
1554 if (port->peer)
1555 strlcpy(ptr, X509_NAME_to_cstring(X509_get_issuer_name(port->peer)), len);
1556 else
1557 ptr[0] = '0円';
1558}
1559
1560void
1561 be_tls_get_peer_serial(Port *port, char *ptr, size_t len)
1562{
1563 if (port->peer)
1564 {
1565 ASN1_INTEGER *serial;
1566 BIGNUM *b;
1567 char *decimal;
1568
1569 serial = X509_get_serialNumber(port->peer);
1570 b = ASN1_INTEGER_to_BN(serial, NULL);
1571 decimal = BN_bn2dec(b);
1572
1573 BN_free(b);
1574 strlcpy(ptr, decimal, len);
1575 OPENSSL_free(decimal);
1576 }
1577 else
1578 ptr[0] = '0円';
1579}
1580
1581char *
1582 be_tls_get_certificate_hash(Port *port, size_t *len)
1583{
1584 X509 *server_cert;
1585 char *cert_hash;
1586 const EVP_MD *algo_type = NULL;
1587 unsigned char hash[EVP_MAX_MD_SIZE]; /* size for SHA-512 */
1588 unsigned int hash_size;
1589 int algo_nid;
1590
1591 *len = 0;
1592 server_cert = SSL_get_certificate(port->ssl);
1593 if (server_cert == NULL)
1594 return NULL;
1595
1596 /*
1597 * Get the signature algorithm of the certificate to determine the hash
1598 * algorithm to use for the result. Prefer X509_get_signature_info(),
1599 * introduced in OpenSSL 1.1.1, which can handle RSA-PSS signatures.
1600 */
1601#if HAVE_X509_GET_SIGNATURE_INFO
1602 if (!X509_get_signature_info(server_cert, &algo_nid, NULL, NULL, NULL))
1603#else
1604 if (!OBJ_find_sigid_algs(X509_get_signature_nid(server_cert),
1605 &algo_nid, NULL))
1606#endif
1607 elog(ERROR, "could not determine server certificate signature algorithm");
1608
1609 /*
1610 * The TLS server's certificate bytes need to be hashed with SHA-256 if
1611 * its signature algorithm is MD5 or SHA-1 as per RFC 5929
1612 * (https://tools.ietf.org/html/rfc5929#section-4.1). If something else
1613 * is used, the same hash as the signature algorithm is used.
1614 */
1615 switch (algo_nid)
1616 {
1617 case NID_md5:
1618 case NID_sha1:
1619 algo_type = EVP_sha256();
1620 break;
1621 default:
1622 algo_type = EVP_get_digestbynid(algo_nid);
1623 if (algo_type == NULL)
1624 elog(ERROR, "could not find digest for NID %s",
1625 OBJ_nid2sn(algo_nid));
1626 break;
1627 }
1628
1629 /* generate and save the certificate hash */
1630 if (!X509_digest(server_cert, algo_type, hash, &hash_size))
1631 elog(ERROR, "could not generate server certificate hash");
1632
1633 cert_hash = palloc(hash_size);
1634 memcpy(cert_hash, hash, hash_size);
1635 *len = hash_size;
1636
1637 return cert_hash;
1638}
1639
1640/*
1641 * Convert an X509 subject name to a cstring.
1642 *
1643 */
1644static char *
1645 X509_NAME_to_cstring(X509_NAME *name)
1646{
1647 BIO *membuf = BIO_new(BIO_s_mem());
1648 int i,
1649 nid,
1650 count = X509_NAME_entry_count(name);
1651 X509_NAME_ENTRY *e;
1652 ASN1_STRING *v;
1653 const char *field_name;
1654 size_t size;
1655 char nullterm;
1656 char *sp;
1657 char *dp;
1658 char *result;
1659
1660 if (membuf == NULL)
1661 ereport(ERROR,
1662 (errcode(ERRCODE_OUT_OF_MEMORY),
1663 errmsg("could not create BIO")));
1664
1665 (void) BIO_set_close(membuf, BIO_CLOSE);
1666 for (i = 0; i < count; i++)
1667 {
1668 e = X509_NAME_get_entry(name, i);
1669 nid = OBJ_obj2nid(X509_NAME_ENTRY_get_object(e));
1670 if (nid == NID_undef)
1671 ereport(ERROR,
1672 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1673 errmsg("could not get NID for ASN1_OBJECT object")));
1674 v = X509_NAME_ENTRY_get_data(e);
1675 field_name = OBJ_nid2sn(nid);
1676 if (field_name == NULL)
1677 field_name = OBJ_nid2ln(nid);
1678 if (field_name == NULL)
1679 ereport(ERROR,
1680 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1681 errmsg("could not convert NID %d to an ASN1_OBJECT structure", nid)));
1682 BIO_printf(membuf, "/%s=", field_name);
1683 ASN1_STRING_print_ex(membuf, v,
1684 ((ASN1_STRFLGS_RFC2253 & ~ASN1_STRFLGS_ESC_MSB)
1685 | ASN1_STRFLGS_UTF8_CONVERT));
1686 }
1687
1688 /* ensure null termination of the BIO's content */
1689 nullterm = '0円';
1690 BIO_write(membuf, &nullterm, 1);
1691 size = BIO_get_mem_data(membuf, &sp);
1692 dp = pg_any_to_server(sp, size - 1, PG_UTF8);
1693
1694 result = pstrdup(dp);
1695 if (dp != sp)
1696 pfree(dp);
1697 if (BIO_free(membuf) != 1)
1698 elog(ERROR, "could not free OpenSSL BIO structure");
1699
1700 return result;
1701}
1702
1703/*
1704 * Convert TLS protocol version GUC enum to OpenSSL values
1705 *
1706 * This is a straightforward one-to-one mapping, but doing it this way makes
1707 * the definitions of ssl_min_protocol_version and ssl_max_protocol_version
1708 * independent of OpenSSL availability and version.
1709 *
1710 * If a version is passed that is not supported by the current OpenSSL
1711 * version, then we return -1. If a nonnegative value is returned,
1712 * subsequent code can assume it's working with a supported version.
1713 *
1714 * Note: this is rather similar to libpq's routine in fe-secure-openssl.c,
1715 * so make sure to update both routines if changing this one.
1716 */
1717static int
1718 ssl_protocol_version_to_openssl(int v)
1719{
1720 switch (v)
1721 {
1722 case PG_TLS_ANY:
1723 return 0;
1724 case PG_TLS1_VERSION:
1725 return TLS1_VERSION;
1726 case PG_TLS1_1_VERSION:
1727#ifdef TLS1_1_VERSION
1728 return TLS1_1_VERSION;
1729#else
1730 break;
1731#endif
1732 case PG_TLS1_2_VERSION:
1733#ifdef TLS1_2_VERSION
1734 return TLS1_2_VERSION;
1735#else
1736 break;
1737#endif
1738 case PG_TLS1_3_VERSION:
1739#ifdef TLS1_3_VERSION
1740 return TLS1_3_VERSION;
1741#else
1742 break;
1743#endif
1744 }
1745
1746 return -1;
1747}
1748
1749/*
1750 * Likewise provide a mapping to strings.
1751 */
1752static const char *
1753 ssl_protocol_version_to_string(int v)
1754{
1755 switch (v)
1756 {
1757 case PG_TLS_ANY:
1758 return "any";
1759 case PG_TLS1_VERSION:
1760 return "TLSv1";
1761 case PG_TLS1_1_VERSION:
1762 return "TLSv1.1";
1763 case PG_TLS1_2_VERSION:
1764 return "TLSv1.2";
1765 case PG_TLS1_3_VERSION:
1766 return "TLSv1.3";
1767 }
1768
1769 return "(unrecognized)";
1770}
1771
1772
1773static void
1774 default_openssl_tls_init(SSL_CTX *context, bool isServerStart)
1775{
1776 if (isServerStart)
1777 {
1778 if (ssl_passphrase_command[0])
1779 SSL_CTX_set_default_passwd_cb(context, ssl_external_passwd_cb);
1780 }
1781 else
1782 {
1783 if (ssl_passphrase_command[0] && ssl_passphrase_command_supports_reload)
1784 SSL_CTX_set_default_passwd_cb(context, ssl_external_passwd_cb);
1785 else
1786
1787 /*
1788 * If reloading and no external command is configured, override
1789 * OpenSSL's default handling of passphrase-protected files,
1790 * because we don't want to prompt for a passphrase in an
1791 * already-running server.
1792 */
1793 SSL_CTX_set_default_passwd_cb(context, dummy_ssl_passwd_cb);
1794 }
1795}
bool check_ssl_key_file_permissions(const char *ssl_key_file, bool isServerStart)
int run_ssl_passphrase_command(const char *prompt, bool is_server_start, char *buf, int size)
const char * be_tls_get_version(Port *port)
static const char * ssl_protocol_version_to_string(int v)
static const char * cert_errdetail
static void info_cb(const SSL *ssl, int type, int args)
static const char * SSLerrmessage(unsigned long ecode)
ssize_t be_tls_write(Port *port, const void *ptr, size_t len, int *waitfor)
void be_tls_destroy(void)
int be_tls_init(bool isServerStart)
static long port_bio_ctrl(BIO *h, int cmd, long num, void *ptr)
openssl_tls_init_hook_typ openssl_tls_init_hook
int be_tls_get_cipher_bits(Port *port)
int be_tls_open_server(Port *port)
char * be_tls_get_certificate_hash(Port *port, size_t *len)
static int alpn_cb(SSL *ssl, const unsigned char **out, unsigned char *outlen, const unsigned char *in, unsigned int inlen, void *userdata)
const char * be_tls_get_cipher(Port *port)
static const char * SSLerrmessageExt(unsigned long ecode, const char *replacement)
static DH * load_dh_buffer(const char *buffer, size_t len)
static int dummy_ssl_passwd_cb(char *buf, int size, int rwflag, void *userdata)
static void default_openssl_tls_init(SSL_CTX *context, bool isServerStart)
static int ssl_set_port_bio(Port *port)
void be_tls_get_peer_serial(Port *port, char *ptr, size_t len)
static int ssl_protocol_version_to_openssl(int v)
static bool initialize_dh(SSL_CTX *context, bool isServerStart)
void be_tls_close(Port *port)
void be_tls_get_peer_issuer_name(Port *port, char *ptr, size_t len)
ssize_t be_tls_read(Port *port, void *ptr, size_t len, int *waitfor)
static char * X509_NAME_to_cstring(X509_NAME *name)
static BIO_METHOD * port_bio_method(void)
static int ssl_external_passwd_cb(char *buf, int size, int rwflag, void *userdata)
static char * prepare_cert_name(char *name)
static SSL_CTX * SSL_context
static bool ssl_is_server_start
static int verify_cb(int ok, X509_STORE_CTX *ctx)
static BIO_METHOD * port_bio_method_ptr
static bool initialize_ecdh(SSL_CTX *context, bool isServerStart)
static int port_bio_read(BIO *h, char *buf, int size)
static int port_bio_write(BIO *h, const char *buf, int size)
static bool dummy_ssl_passwd_cb_called
#define MAXLEN
static DH * load_dh_file(char *filename, bool isServerStart)
static const unsigned char alpn_protos[]
void be_tls_get_peer_subject_name(Port *port, char *ptr, size_t len)
char * ssl_crl_dir
Definition: be-secure.c:41
char * ssl_dh_params_file
Definition: be-secure.c:42
int ssl_min_protocol_version
Definition: be-secure.c:60
ssize_t secure_raw_read(Port *port, void *ptr, size_t len)
Definition: be-secure.c:268
char * ssl_cert_file
Definition: be-secure.c:37
bool SSLPreferServerCiphers
Definition: be-secure.c:58
int ssl_max_protocol_version
Definition: be-secure.c:61
char * ssl_passphrase_command
Definition: be-secure.c:43
bool ssl_passphrase_command_supports_reload
Definition: be-secure.c:44
char * SSLCipherSuites
Definition: be-secure.c:51
char * SSLECDHCurve
Definition: be-secure.c:55
char * SSLCipherList
Definition: be-secure.c:52
char * ssl_key_file
Definition: be-secure.c:38
ssize_t secure_raw_write(Port *port, const void *ptr, size_t len)
Definition: be-secure.c:377
char * ssl_crl_file
Definition: be-secure.c:40
char * ssl_ca_file
Definition: be-secure.c:39
int errcode_for_socket_access(void)
Definition: elog.c:954
int errmsg_internal(const char *fmt,...)
Definition: elog.c:1161
int errdetail_internal(const char *fmt,...)
Definition: elog.c:1234
int errcode_for_file_access(void)
Definition: elog.c:877
int errdetail(const char *fmt,...)
Definition: elog.c:1207
int errhint(const char *fmt,...)
Definition: elog.c:1321
int errcode(int sqlerrcode)
Definition: elog.c:854
int errmsg(const char *fmt,...)
Definition: elog.c:1071
_
#define _(x)
Definition: elog.c:91
#define LOG
Definition: elog.h:31
#define COMMERROR
Definition: elog.h:33
#define FATAL
Definition: elog.h:41
#define DEBUG2
Definition: elog.h:29
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:226
#define ereport(elevel,...)
Definition: elog.h:150
#define DEBUG4
Definition: elog.h:27
void err(int eval, const char *fmt,...)
Definition: err.c:43
int FreeFile(FILE *file)
Definition: fd.c:2840
FILE * AllocateFile(const char *name, const char *mode)
Definition: fd.c:2641
const char * GetConfigOption(const char *name, bool missing_ok, bool restrict_privileged)
Definition: guc.c:4361
Assert(PointerIsAligned(start, uint64))
const char * str
b
int b
Definition: isn.c:74
i
int i
Definition: isn.c:77
int WaitLatchOrSocket(Latch *latch, int wakeEvents, pgsocket sock, long timeout, uint32 wait_event_info)
Definition: latch.c:223
@ PG_TLS1_VERSION
Definition: libpq.h:149
@ PG_TLS1_3_VERSION
Definition: libpq.h:152
@ PG_TLS1_1_VERSION
Definition: libpq.h:150
@ PG_TLS1_2_VERSION
Definition: libpq.h:151
@ PG_TLS_ANY
Definition: libpq.h:148
char * pg_any_to_server(const char *s, int len, int encoding)
Definition: mbutils.c:677
void * MemoryContextAlloc(MemoryContext context, Size size)
Definition: mcxt.c:1229
char * pstrdup(const char *in)
Definition: mcxt.c:1759
void pfree(void *pointer)
Definition: mcxt.c:1594
MemoryContext TopMemoryContext
Definition: mcxt.c:166
void * palloc(Size size)
Definition: mcxt.c:1365
args
const void size_t len
static char * filename
Definition: pg_dumpall.c:120
static int port
Definition: pg_regress.c:115
static char * buf
Definition: pg_test_fsync.c:72
@ PG_UTF8
Definition: pg_wchar.h:232
#define strerror
Definition: port.h:252
#define snprintf
Definition: port.h:239
size_t strlcpy(char *dst, const char *src, size_t siz)
Definition: strlcpy.c:45
#define PG_ALPN_PROTOCOL
Definition: pqcomm.h:165
#define PG_ALPN_PROTOCOL_VECTOR
Definition: pqcomm.h:166
e
e
Definition: preproc-init.c:82
static unsigned hash(unsigned *uv, int n)
Definition: rege_dfa.c:715
static void error(void)
Definition: sql-dyntest.c:147
char * pg_clean_ascii(const char *str, int alloc_flags)
Definition: string.c:85
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:145
void appendStringInfoChar(StringInfo str, char ch)
Definition: stringinfo.c:242
void initStringInfo(StringInfo str)
Definition: stringinfo.c:97
Definition: libpq-be.h:129
const char * type
const char * name
#define WL_SOCKET_READABLE
Definition: waiteventset.h:35
#define WL_EXIT_ON_PM_DEATH
Definition: waiteventset.h:39
#define WL_SOCKET_WRITEABLE
Definition: waiteventset.h:36
#define EINTR
Definition: win32_port.h:364
#define EWOULDBLOCK
Definition: win32_port.h:370
#define ECONNRESET
Definition: win32_port.h:374
#define EAGAIN
Definition: win32_port.h:362

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