2 * socket.c -- socket library functions
4 * Copyright 1998 by Eric S. Raymond.
5 * For license terms, see the file COPYING in this directory.
12 #include <ctype.h> /* isspace() */
15 #endif /* HAVE_MEMORY_H */
16 #include <sys/types.h>
18 #ifndef HAVE_NET_SOCKET_H
19 #include <sys/socket.h>
21 #include <net/socket.h>
24 #include <netinet/in.h>
25 #ifdef HAVE_ARPA_INET_H
26 #include <arpa/inet.h>
32 #if TIME_WITH_SYS_TIME
33 # include <sys/time.h>
37 # include <sys/time.h>
44 #include "fetchmail.h"
45 #include "getaddrinfo.h"
49 /* Defines to allow Cygwin to play nice... */
50 #define fm_close(a) close(a)
51 #define fm_write(a,b,c) write(a,b,c)
52 #define fm_peek(a,b,c) recv(a,b,c, MSG_PEEK)
55 #define fm_read(a,b,c) cygwin_read(a,b,c)
56 static ssize_t cygwin_read(int sock, void *buf, size_t count);
57 #else /* ! __CYGWIN__ */
58 #define fm_read(a,b,c) read(a,b,c)
59 #endif /* __CYGWIN__ */
61 /* We need to define h_errno only if it is not already */
63 # if !HAVE_DECL_H_ERRNO
66 #endif /* ndef h_errno */
68 #ifdef HAVE_SOCKETPAIR
69 static char *const *parse_plugin(const char *plugin, const char *host, const char *service)
73 char *cp, *plugin_copy;
74 unsigned int plugin_copy_len;
75 unsigned int plugin_offset = 0, plugin_copy_offset = 0;
76 unsigned int i, s = 2 * sizeof(char*), host_count = 0, service_count = 0;
77 unsigned int plugin_len = strlen(plugin);
78 unsigned int host_len = strlen(host);
79 unsigned int service_len = strlen(service);
81 for (c = p = plugin; *c; c++)
82 { if (isspace((unsigned char)*c) && !isspace((unsigned char)*p))
84 if (*p == '%' && *c == 'h')
86 if (*p == '%' && *c == 'p')
91 plugin_copy_len = plugin_len + host_len * host_count + service_len * service_count;
92 plugin_copy = (char *)malloc(plugin_copy_len + 1);
95 report(stderr, GT_("fetchmail: malloc failed\n"));
99 while (plugin_copy_offset < plugin_copy_len)
100 { if ((plugin[plugin_offset] == '%') && (plugin[plugin_offset + 1] == 'h'))
101 { strcpy(plugin_copy + plugin_copy_offset, host);
103 plugin_copy_offset += host_len;
105 else if ((plugin[plugin_offset] == '%') && (plugin[plugin_offset + 1] == 'p'))
106 { strcpy(plugin_copy + plugin_copy_offset, service);
108 plugin_copy_offset += service_len;
111 { plugin_copy[plugin_copy_offset] = plugin[plugin_offset];
113 plugin_copy_offset++;
116 plugin_copy[plugin_copy_len] = 0;
118 argvec = (char **)malloc(s);
121 report(stderr, GT_("fetchmail: malloc failed\n"));
124 memset(argvec, 0, s);
125 for (p = cp = plugin_copy, i = 0; *cp; cp++)
126 { if ((!isspace((unsigned char)*cp)) && (cp == p ? 1 : isspace((unsigned char)*p))) {
132 for (cp = plugin_copy; *cp; cp++)
133 { if (isspace((unsigned char)*cp))
139 static int handle_plugin(const char *host,
140 const char *service, const char *plugin)
141 /* get a socket mediated through a given external command */
147 * The author of this code, Felix von Leitner <felix@convergence.de>, says:
148 * he chose socketpair() instead of pipe() because socketpair creates
149 * bidirectional sockets while allegedly some pipe() implementations don't.
151 if (socketpair(AF_UNIX,SOCK_STREAM,0,fds))
153 report(stderr, GT_("fetchmail: socketpair failed\n"));
159 report(stderr, GT_("fetchmail: fork failed\n"));
162 /* fds[1] is the parent's end; close it for proper EOF
164 (void) close(fds[1]);
165 if ( (dup2(fds[0],0) == -1) || (dup2(fds[0],1) == -1) ) {
166 report(stderr, GT_("dup2 failed\n"));
169 /* fds[0] is now connected to 0 and 1; close it */
170 (void) close(fds[0]);
171 if (outlevel >= O_VERBOSE)
172 report(stderr, GT_("running %s (host %s service %s)\n"), plugin, host, service);
173 argvec = parse_plugin(plugin,host,service);
174 execvp(*argvec, argvec);
175 report(stderr, GT_("execvp(%s) failed\n"), *argvec);
178 default: /* parent */
182 /* fds[0] is the child's end; close it for proper EOF detection */
183 (void) close(fds[0]);
186 #endif /* HAVE_SOCKETPAIR */
190 int SockCheckOpen(int fd)
191 /* poll given socket; is it selectable? */
199 FD_ZERO(&r); FD_ZERO(&w); FD_ZERO(&e);
202 tv.tv_sec = 0; tv.tv_usec = 0;
203 rt = select(fd+1, &r, &w, &e, &tv);
204 if (rt == -1 && (errno != EAGAIN && errno != EINTR))
210 #endif /* __UNUSED__ */
212 int UnixOpen(const char *path)
215 struct sockaddr_un ad;
216 memset(&ad, 0, sizeof(ad));
217 ad.sun_family = AF_UNIX;
218 strncpy(ad.sun_path, path, sizeof(ad.sun_path)-1);
220 sock = socket( AF_UNIX, SOCK_STREAM, 0 );
227 /* Socket opened saved. Usefull if connect timeout
228 * because it can be closed.
230 mailserver_socket_temp = sock;
232 if (connect(sock, (struct sockaddr *) &ad, sizeof(ad)) < 0)
235 fm_close(sock); /* don't use SockClose, no traffic yet */
241 /* No connect timeout, then no need to set mailserver_socket_temp */
242 mailserver_socket_temp = -1;
247 int SockOpen(const char *host, const char *service,
248 const char *plugin, struct addrinfo **ai0)
250 struct addrinfo *ai, req;
253 char errbuf[8192] = "";
255 #ifdef HAVE_SOCKETPAIR
257 return handle_plugin(host,service,plugin);
258 #endif /* HAVE_SOCKETPAIR */
260 memset(&req, 0, sizeof(struct addrinfo));
261 req.ai_socktype = SOCK_STREAM;
263 req.ai_flags = AI_ADDRCONFIG;
266 i = fm_getaddrinfo(host, service, &req, ai0);
268 report(stderr, GT_("getaddrinfo(\"%s\",\"%s\") error: %s\n"),
269 host, service, gai_strerror(i));
270 if (i == EAI_SERVICE)
271 report(stderr, GT_("Try adding the --service option (see also FAQ item R12).\n"));
275 /* NOTE a Linux bug here - getaddrinfo will happily return 127.0.0.1
276 * twice if no IPv6 is configured */
278 for (ord = 0, ai = *ai0; ai; ord++, ai = ai->ai_next) {
279 char buf[256]; /* hostname */
280 char pb[256]; /* service name */
281 int gnie; /* getnameinfo result code */
283 gnie = getnameinfo(ai->ai_addr, ai->ai_addrlen, buf, sizeof(buf), NULL, 0, NI_NUMERICHOST);
285 snprintf(buf, sizeof(buf), GT_("unknown (%s)"), gai_strerror(gnie));
286 gnie = getnameinfo(ai->ai_addr, ai->ai_addrlen, NULL, 0, pb, sizeof(pb), NI_NUMERICSERV);
288 snprintf(pb, sizeof(pb), GT_("unknown (%s)"), gai_strerror(gnie));
290 if (outlevel >= O_VERBOSE)
291 report_build(stdout, GT_("Trying to connect to %s/%s..."), buf, pb);
292 i = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
295 /* mask EAFNOSUPPORT errors, they confuse users for
296 * multihomed hosts */
297 if (errno != EAFNOSUPPORT)
299 if (outlevel >= O_VERBOSE)
300 report_complete(stdout, GT_("cannot create socket: %s\n"), strerror(e));
301 snprintf(errbuf+strlen(errbuf), sizeof(errbuf)-strlen(errbuf),\
302 GT_("name %d: cannot create socket family %d type %d: %s\n"), ord, ai->ai_family, ai->ai_socktype, strerror(e));
306 /* Save socket descriptor.
307 * Used to close the socket after connect timeout. */
308 mailserver_socket_temp = i;
310 if (connect(i, (struct sockaddr *) ai->ai_addr, ai->ai_addrlen) < 0) {
313 /* additionally, suppress IPv4 network unreach errors */
314 if (e != EAFNOSUPPORT)
317 if (outlevel >= O_VERBOSE)
318 report_complete(stdout, GT_("connection failed.\n"));
319 if (outlevel >= O_VERBOSE)
320 report(stderr, GT_("connection to %s:%s [%s/%s] failed: %s.\n"), host, service, buf, pb, strerror(e));
321 snprintf(errbuf+strlen(errbuf), sizeof(errbuf)-strlen(errbuf), GT_("name %d: connection to %s:%s [%s/%s] failed: %s.\n"), ord, host, service, buf, pb, strerror(e));
326 if (outlevel >= O_VERBOSE)
327 report_complete(stdout, GT_("connected.\n"));
330 /* No connect timeout, then no need to set mailserver_socket_temp */
331 mailserver_socket_temp = -1;
336 fm_freeaddrinfo(*ai0);
340 report(stderr, GT_("Connection errors for this poll:\n%s"), errbuf);
348 int SockPrintf(int sock, const char* format, ...)
353 va_start(ap, format) ;
354 vsnprintf(buf, sizeof(buf), format, ap);
356 return SockWrite(sock, buf, strlen(buf));
360 #include <openssl/ssl.h>
361 #include <openssl/err.h>
362 #include <openssl/pem.h>
363 #include <openssl/x509v3.h>
364 #include <openssl/rand.h>
366 static SSL_CTX *_ctx[FD_SETSIZE];
367 static SSL *_ssl_context[FD_SETSIZE];
369 static SSL *SSLGetContext( int );
370 #endif /* SSL_ENABLE */
372 int SockWrite(int sock, const char *buf, int len)
382 if( NULL != ( ssl = SSLGetContext( sock ) ) )
383 n = SSL_write(ssl, buf, len);
385 #endif /* SSL_ENABLE */
386 n = fm_write(sock, buf, len);
396 int SockRead(int sock, char *buf, int len)
398 char *newline, *bp = buf;
408 * The reason for these gymnastics is that we want two things:
409 * (1) to read \n-terminated lines,
410 * (2) to return the true length of data read, even if the
411 * data coming in has embedded NULS.
414 if( NULL != ( ssl = SSLGetContext( sock ) ) ) {
416 /* OK... SSL_peek works a little different from MSG_PEEK
417 Problem is that SSL_peek can return 0 if there
418 is no data currently available. If, on the other
419 hand, we loose the socket, we also get a zero, but
420 the SSL_read then SEGFAULTS! To deal with this,
421 we'll check the error code any time we get a return
422 of zero from SSL_peek. If we have an error, we bail.
423 If we don't, we read one character in SSL_read and
424 loop. This should continue to work even if they
425 later change the behavior of SSL_peek
426 to "fix" this problem... :-( */
427 if ((n = SSL_peek(ssl, bp, len)) < 0) {
428 (void)SSL_get_error(ssl, n);
432 /* SSL_peek says no data... Does he mean no data
433 or did the connection blow up? If we got an error
435 if (0 != SSL_get_error(ssl, n)) {
438 /* We didn't get an error so read at least one
439 character at this point and loop */
441 /* Make sure newline start out NULL!
442 * We don't have a string to pass through
443 * the strchr at this point yet */
445 } else if ((newline = (char *)memchr(bp, '\n', n)) != NULL)
446 n = newline - bp + 1;
447 /* Matthias Andree: SSL_read can return 0, in that case
448 * we must call SSL_get_error to figure if there was
449 * an error or just a "no data" condition */
450 if ((n = SSL_read(ssl, bp, n)) <= 0) {
451 if ((n = SSL_get_error(ssl, n))) {
455 /* Check for case where our single character turned out to
456 * be a newline... (It wasn't going to get caught by
457 * the strchr above if it came from the hack... ). */
458 if( NULL == newline && 1 == n && '\n' == *bp ) {
459 /* Got our newline - this will break
460 out of the loop now */
465 #endif /* SSL_ENABLE */
468 if ((n = fm_peek(sock, bp, len)) <= 0)
470 if ((newline = (char *)memchr(bp, '\n', n)) != NULL)
471 n = newline - bp + 1;
472 if ((n = fm_read(sock, bp, n)) == -1)
484 int SockPeek(int sock)
485 /* peek at the next socket character without actually reading it */
494 if( NULL != ( ssl = SSLGetContext( sock ) ) ) {
495 n = SSL_peek(ssl, &ch, 1);
497 (void)SSL_get_error(ssl, n);
501 /* This code really needs to implement a "hold back"
502 * to simulate a functioning SSL_peek()... sigh...
503 * Has to be coordinated with the read code above.
504 * Next on the list todo... */
506 /* SSL_peek says 0... Does that mean no data
507 or did the connection blow up? If we got an error
509 if(0 != SSL_get_error(ssl, n)) {
513 /* Haven't seen this case actually occur, but...
514 if the problem in SockRead can occur, this should
515 be possible... Just not sure what to do here.
516 This should be a safe "punt" the "peek" but don't
517 "punt" the "session"... */
519 return 0; /* Give him a '\0' character */
523 #endif /* SSL_ENABLE */
524 n = fm_peek(sock, &ch, 1);
533 static char *_ssl_server_cname = NULL;
534 static int _check_fp;
535 static char *_check_digest;
536 static char *_server_label;
537 static int _depth0ck;
538 static int _firstrun;
539 static int _prev_err;
540 static int _verify_ok;
542 SSL *SSLGetContext( int sock )
544 if( sock < 0 || (unsigned)sock > FD_SETSIZE )
546 if( _ctx[sock] == NULL )
548 return _ssl_context[sock];
551 /* ok_return (preverify_ok) is 1 if this stage of certificate verification
552 passed, or 0 if it failed. This callback lets us display informative
553 errors, and perform additional validation (e.g. CN matches) */
554 static int SSL_verify_callback( int ok_return, X509_STORE_CTX *ctx, int strict )
556 #define SSLverbose (((outlevel) >= O_DEBUG) || ((outlevel) >= O_VERBOSE && (depth) == 0))
560 unsigned char digest[EVP_MAX_MD_SIZE];
561 char text[EVP_MAX_MD_SIZE * 3 + 1], *tp, *te;
562 const EVP_MD *digest_tp;
563 unsigned int dsz, esz;
564 X509_NAME *subj, *issuer;
567 x509_cert = X509_STORE_CTX_get_current_cert(ctx);
568 err = X509_STORE_CTX_get_error(ctx);
569 depth = X509_STORE_CTX_get_error_depth(ctx);
571 subj = X509_get_subject_name(x509_cert);
572 issuer = X509_get_issuer_name(x509_cert);
574 if (outlevel >= O_VERBOSE) {
575 if (depth == 0 && SSLverbose)
576 report(stderr, GT_("Server certificate:\n"));
581 report(stdout, GT_("Certificate chain, from root to peer, starting at depth %d:\n"), depth);
584 report(stdout, GT_("Certificate at depth %d:\n"), depth);
589 if ((i = X509_NAME_get_text_by_NID(issuer, NID_organizationName, buf, sizeof(buf))) != -1) {
590 report(stdout, GT_("Issuer Organization: %s\n"), (tt = sdump(buf, i)));
592 if ((size_t)i >= sizeof(buf) - 1)
593 report(stdout, GT_("Warning: Issuer Organization Name too long (possibly truncated).\n"));
595 report(stdout, GT_("Unknown Organization\n"));
596 if ((i = X509_NAME_get_text_by_NID(issuer, NID_commonName, buf, sizeof(buf))) != -1) {
597 report(stdout, GT_("Issuer CommonName: %s\n"), (tt = sdump(buf, i)));
599 if ((size_t)i >= sizeof(buf) - 1)
600 report(stdout, GT_("Warning: Issuer CommonName too long (possibly truncated).\n"));
602 report(stdout, GT_("Unknown Issuer CommonName\n"));
606 if ((i = X509_NAME_get_text_by_NID(subj, NID_commonName, buf, sizeof(buf))) != -1) {
608 report(stdout, GT_("Subject CommonName: %s\n"), (tt = sdump(buf, i)));
611 if ((size_t)i >= sizeof(buf) - 1) {
612 /* Possible truncation. In this case, this is a DNS name, so this
613 * is really bad. We do not tolerate this even in the non-strict case. */
614 report(stderr, GT_("Bad certificate: Subject CommonName too long!\n"));
617 if ((size_t)i > strlen(buf)) {
618 /* Name contains embedded NUL characters, so we complain. This is likely
619 * a certificate spoofing attack. */
620 report(stderr, GT_("Bad certificate: Subject CommonName contains NUL, aborting!\n"));
625 if (depth == 0) { /* peer certificate */
630 if ((i = X509_NAME_get_text_by_NID(subj, NID_commonName, buf, sizeof(buf))) != -1) {
631 if (_ssl_server_cname != NULL) {
633 char *p2 = _ssl_server_cname;
635 STACK_OF(GENERAL_NAME) *gens;
637 /* RFC 2595 section 2.4: find a matching name
638 * first find a match among alternative names */
639 gens = (STACK_OF(GENERAL_NAME) *)X509_get_ext_d2i(x509_cert, NID_subject_alt_name, NULL, NULL);
642 for (j = 0, r = sk_GENERAL_NAME_num(gens); j < r; ++j) {
643 const GENERAL_NAME *gn = sk_GENERAL_NAME_value(gens, j);
644 if (gn->type == GEN_DNS) {
645 char *pp1 = (char *)gn->d.ia5->data;
646 char *pp2 = _ssl_server_cname;
647 if (outlevel >= O_VERBOSE) {
648 report(stdout, GT_("Subject Alternative Name: %s\n"), (tt = sdump(pp1, (size_t)gn->d.ia5->length)));
651 /* Name contains embedded NUL characters, so we complain. This
652 * is likely a certificate spoofing attack. */
653 if ((size_t)gn->d.ia5->length != strlen(pp1)) {
654 report(stderr, GT_("Bad certificate: Subject Alternative Name contains NUL, aborting!\n"));
655 sk_GENERAL_NAME_free(gens);
658 if (name_match(pp1, pp2)) {
663 sk_GENERAL_NAME_free(gens);
665 if (name_match(p1, p2)) {
669 if (strict || SSLverbose) {
671 GT_("Server CommonName mismatch: %s != %s\n"),
672 (tt = sdump(buf, i)), _ssl_server_cname );
677 } else if (ok_return) {
678 report(stderr, GT_("Server name not set, could not verify certificate!\n"));
679 if (strict) return (0);
682 if (outlevel >= O_VERBOSE)
683 report(stdout, GT_("Unknown Server CommonName\n"));
684 if (ok_return && strict) {
685 report(stderr, GT_("Server name not specified in certificate!\n"));
689 /* Print the finger print. Note that on errors, we might print it more than once
690 * normally; we kluge around that by using a global variable. */
691 if (_check_fp == 1) {
695 digest_tp = EVP_md5();
696 if (digest_tp == NULL) {
697 report(stderr, GT_("EVP_md5() failed!\n"));
700 if (!X509_digest(x509_cert, digest_tp, digest, &dsz)) {
701 report(stderr, GT_("Out of memory!\n"));
705 te = text + sizeof(text);
706 for (dp = 0; dp < dsz; dp++) {
707 esz = snprintf(tp, te - tp, dp > 0 ? ":%02X" : "%02X", digest[dp]);
708 if (esz >= (size_t)(te - tp)) {
709 report(stderr, GT_("Digest text buffer too small!\n"));
714 if (outlevel > O_NORMAL)
715 report(stdout, GT_("%s key fingerprint: %s\n"), _server_label, text);
716 if (_check_digest != NULL) {
717 if (strcasecmp(text, _check_digest) == 0) {
718 if (outlevel > O_NORMAL)
719 report(stdout, GT_("%s fingerprints match.\n"), _server_label);
721 report(stderr, GT_("%s fingerprints do not match!\n"), _server_label);
724 } /* if (_check_digest != NULL) */
725 } /* if (_check_fp) */
726 } /* if (depth == 0 && !_depth0ck) */
728 if (err != X509_V_OK && err != _prev_err && !(_check_fp != 0 && _check_digest && !strict)) {
731 report(stderr, GT_("Server certificate verification error: %s\n"), X509_verify_cert_error_string(err));
732 /* We gave the error code, but maybe we can add some more details for debugging */
735 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
736 X509_NAME_oneline(issuer, buf, sizeof(buf));
737 buf[sizeof(buf) - 1] = '\0';
738 report(stderr, GT_("unknown issuer (first %d characters): %s\n"), (int)(sizeof(buf)-1), buf);
739 report(stderr, GT_("This error usually happens when the server provides an incomplete certificate "
740 "chain, which is nothing fetchmail could do anything about. For details, "
741 "please see the README.SSL-SERVER document that comes with fetchmail.\n"));
743 case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
744 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY:
745 case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN:
746 X509_NAME_oneline(subj, buf, sizeof(buf));
747 buf[sizeof(buf) - 1] = '\0';
748 report(stderr, GT_("This means that the root signing certificate (issued for %s) is not in the "
749 "trusted CA certificate locations, or that c_rehash needs to be run "
750 "on the certificate directory. For details, please "
751 "see the documentation of --sslcertpath and --sslcertfile in the manual page.\n"), buf);
758 * If not in strict checking mode (--sslcertck), override this
759 * and pretend that verification had succeeded.
761 _verify_ok &= ok_return;
767 static int SSL_nock_verify_callback( int ok_return, X509_STORE_CTX *ctx )
769 return SSL_verify_callback(ok_return, ctx, 0);
772 static int SSL_ck_verify_callback( int ok_return, X509_STORE_CTX *ctx )
774 return SSL_verify_callback(ok_return, ctx, 1);
778 /* get commonName from certificate set in file.
779 * commonName is stored in buffer namebuffer, limited with namebufferlen
781 static const char *SSLCertGetCN(const char *mycert,
782 char *namebuffer, size_t namebufferlen)
784 const char *ret = NULL;
786 X509 *x509_cert = NULL;
787 X509_NAME *certname = NULL;
789 if (namebuffer && namebufferlen > 0) {
790 namebuffer[0] = 0x00;
791 certBio = BIO_new_file(mycert,"r");
793 x509_cert = PEM_read_bio_X509(certBio,NULL,NULL,NULL);
797 certname = X509_get_subject_name(x509_cert);
799 X509_NAME_get_text_by_NID(certname, NID_commonName,
800 namebuffer, namebufferlen) > 0)
802 X509_free(x509_cert);
808 /* performs initial SSL handshake over the connected socket
809 * uses SSL *ssl global variable, which is currently defined
812 int SSLOpen(int sock, char *mycert, char *mykey, const char *myproto, int certck,
813 char *cacertfile, char *certpath,
814 char *fingerprint, char *servercname, char *label, char **remotename)
816 struct stat randstat;
819 SSL_load_error_strings();
821 OpenSSL_add_all_algorithms(); /* see Debian Bug#576430 and manpage */
823 if (stat("/dev/random", &randstat) &&
824 stat("/dev/urandom", &randstat)) {
825 /* Neither /dev/random nor /dev/urandom are present, so add
826 entropy to the SSL PRNG a hard way. */
827 for (i = 0; i < 10000 && ! RAND_status (); ++i) {
830 gettimeofday (&tv, 0);
831 buf[0] = tv.tv_usec & 0xF;
832 buf[2] = (tv.tv_usec & 0xF0) >> 4;
833 buf[3] = (tv.tv_usec & 0xF00) >> 8;
834 buf[1] = (tv.tv_usec & 0xF000) >> 12;
835 RAND_add (buf, sizeof buf, 0.1);
839 if( sock < 0 || (unsigned)sock > FD_SETSIZE ) {
840 report(stderr, GT_("File descriptor out of range for SSL") );
844 /* Make sure a connection referring to an older context is not left */
845 _ssl_context[sock] = NULL;
847 if(!strcasecmp("ssl2",myproto)) {
848 _ctx[sock] = SSL_CTX_new(SSLv2_client_method());
849 } else if(!strcasecmp("ssl3",myproto)) {
850 _ctx[sock] = SSL_CTX_new(SSLv3_client_method());
851 } else if(!strcasecmp("tls1",myproto)) {
852 _ctx[sock] = SSL_CTX_new(TLSv1_client_method());
853 } else if (!strcasecmp("ssl23",myproto)) {
856 fprintf(stderr,GT_("Invalid SSL protocol '%s' specified, using default (SSLv23).\n"), myproto);
861 _ctx[sock] = SSL_CTX_new(SSLv23_client_method());
863 if(_ctx[sock] == NULL) {
864 ERR_print_errors_fp(stderr);
868 SSL_CTX_set_options(_ctx[sock], SSL_OP_ALL);
871 SSL_CTX_set_verify(_ctx[sock], SSL_VERIFY_PEER, SSL_ck_verify_callback);
873 /* In this case, we do not fail if verification fails. However,
874 * we provide the callback for output and possible fingerprint
876 SSL_CTX_set_verify(_ctx[sock], SSL_VERIFY_PEER, SSL_nock_verify_callback);
879 /* Check which trusted X.509 CA certificate store(s) to load */
882 int want_default_cacerts = 0;
884 /* Load user locations if any is given */
885 if (certpath || cacertfile)
886 SSL_CTX_load_verify_locations(_ctx[sock],
887 cacertfile, certpath);
889 want_default_cacerts = 1;
891 tmp = getenv("FETCHMAIL_INCLUDE_DEFAULT_X509_CA_CERTS");
892 if (want_default_cacerts || (tmp && tmp[0])) {
893 SSL_CTX_set_default_verify_paths(_ctx[sock]);
897 _ssl_context[sock] = SSL_new(_ctx[sock]);
899 if(_ssl_context[sock] == NULL) {
900 ERR_print_errors_fp(stderr);
901 SSL_CTX_free(_ctx[sock]);
906 /* This static is for the verify callback */
907 _ssl_server_cname = servercname;
908 _server_label = label;
910 _check_digest = fingerprint;
916 if( mycert || mykey ) {
918 /* Ok... He has a certificate file defined, so lets declare it. If
919 * he does NOT have a separate certificate and private key file then
920 * assume that it's a combined key and certificate file.
929 if ((!*remotename || !**remotename) && SSLCertGetCN(mycert, buffer, sizeof(buffer))) {
931 *remotename = xstrdup(buffer);
933 SSL_use_certificate_file(_ssl_context[sock], mycert, SSL_FILETYPE_PEM);
934 SSL_use_RSAPrivateKey_file(_ssl_context[sock], mykey, SSL_FILETYPE_PEM);
937 if (SSL_set_fd(_ssl_context[sock], sock) == 0
938 || SSL_connect(_ssl_context[sock]) < 1) {
939 ERR_print_errors_fp(stderr);
940 SSL_free( _ssl_context[sock] );
941 _ssl_context[sock] = NULL;
942 SSL_CTX_free(_ctx[sock]);
947 /* Paranoia: was the callback not called as we expected? */
949 report(stderr, GT_("Certificate/fingerprint verification was somehow skipped!\n"));
951 if (fingerprint != NULL || certck) {
952 if( NULL != SSLGetContext( sock ) ) {
953 /* Clean up the SSL stack */
954 SSL_shutdown( _ssl_context[sock] );
955 SSL_free( _ssl_context[sock] );
956 _ssl_context[sock] = NULL;
957 SSL_CTX_free(_ctx[sock]);
964 if (!certck && !fingerprint &&
965 (SSL_get_verify_result(_ssl_context[sock]) != X509_V_OK || !_verify_ok)) {
966 report(stderr, GT_("Warning: the connection is insecure, continuing anyways. (Better use --sslcertck!)\n"));
973 int SockClose(int sock)
974 /* close a socket gracefully */
977 if( NULL != SSLGetContext( sock ) ) {
978 /* Clean up the SSL stack */
979 SSL_shutdown( _ssl_context[sock] );
980 SSL_free( _ssl_context[sock] );
981 _ssl_context[sock] = NULL;
982 SSL_CTX_free(_ctx[sock]);
989 * This hangs in RedHat 6.2 after fetchmail runs for a while a
990 * FIN_WAIT2 comes up in netstat and fetchmail never returns from
991 * the recv system call. (Reported from jtnews
992 * <jtnews@bellatlantic.net>, Wed, 24 May 2000 21:26:02.)
994 * Half-close the connection first so the other end gets notified.
996 * This stops sends but allows receives (effectively, it sends a
998 if (shutdown(sock, 1) == 0) {
1000 /* If there is any data still waiting in the queue, discard it.
1001 * Call recv() until either it returns 0 (meaning we received a FIN)
1002 * or any error occurs. This makes sure all data sent by the other
1003 * side is acknowledged at the TCP level.
1005 if (fm_peek(sock, &ch, 1) > 0)
1006 while (fm_read(sock, &ch, 1) > 0)
1009 #endif /* __UNUSED__ */
1011 /* if there's an error closing at this point, not much we can do */
1012 return(fm_close(sock)); /* this is guarded */
1017 * Workaround Microsoft Winsock recv/WSARecv(..., MSG_PEEK) bug.
1018 * See http://sources.redhat.com/ml/cygwin/2001-08/msg00628.html
1021 static ssize_t cygwin_read(int sock, void *buf, size_t count)
1026 if ((n = read(sock, bp, count)) == (size_t)-1)
1031 if (outlevel >= O_VERBOSE)
1032 report(stdout, GT_("Cygwin socket read retry\n"));
1033 n2 = read(sock, bp + n, count - n);
1034 if (n2 == (size_t)-1 || n + n2 != count) {
1035 report(stderr, GT_("Cygwin socket read retry failed!\n"));
1042 #endif /* __CYGWIN__ */
1046 * Use the chargen service to test input buffering directly.
1047 * You may have to uncomment the `chargen' service description in your
1048 * inetd.conf (and then SIGHUP inetd) for this to work. */
1051 int sock = SockOpen("localhost", "chargen", NULL);
1054 while (SockRead(sock, buf, sizeof(buf)-1))
1055 SockWrite(1, buf, strlen(buf));
1060 /* socket.c ends here */