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>
29 #if defined(STDC_HEADERS)
32 #if defined(HAVE_UNISTD_H)
35 #if defined(HAVE_STDARG_H)
40 #if TIME_WITH_SYS_TIME
41 # include <sys/time.h>
45 # include <sys/time.h>
52 #include "fetchmail.h"
53 #include "getaddrinfo.h"
57 /* Defines to allow Cygwin to play nice... */
58 #define fm_close(a) close(a)
59 #define fm_write(a,b,c) write(a,b,c)
60 #define fm_peek(a,b,c) recv(a,b,c, MSG_PEEK)
63 #define fm_read(a,b,c) cygwin_read(a,b,c)
64 static ssize_t cygwin_read(int sock, void *buf, size_t count);
65 #else /* ! __CYGWIN__ */
66 #define fm_read(a,b,c) read(a,b,c)
67 #endif /* __CYGWIN__ */
69 /* We need to define h_errno only if it is not already */
71 # if !HAVE_DECL_H_ERRNO
74 #endif /* ndef h_errno */
76 #ifdef HAVE_SOCKETPAIR
77 static char *const *parse_plugin(const char *plugin, const char *host, const char *service)
81 char *cp, *plugin_copy;
82 unsigned int plugin_copy_len;
83 unsigned int plugin_offset = 0, plugin_copy_offset = 0;
84 unsigned int i, s = 2 * sizeof(char*), host_count = 0, service_count = 0;
85 unsigned int plugin_len = strlen(plugin);
86 unsigned int host_len = strlen(host);
87 unsigned int service_len = strlen(service);
89 for (c = p = plugin; *c; c++)
90 { if (isspace((unsigned char)*c) && !isspace((unsigned char)*p))
92 if (*p == '%' && *c == 'h')
94 if (*p == '%' && *c == 'p')
99 plugin_copy_len = plugin_len + host_len * host_count + service_len * service_count;
100 plugin_copy = (char *)malloc(plugin_copy_len + 1);
103 report(stderr, GT_("fetchmail: malloc failed\n"));
107 while (plugin_copy_offset < plugin_copy_len)
108 { if ((plugin[plugin_offset] == '%') && (plugin[plugin_offset + 1] == 'h'))
109 { strcpy(plugin_copy + plugin_copy_offset, host);
111 plugin_copy_offset += host_len;
113 else if ((plugin[plugin_offset] == '%') && (plugin[plugin_offset + 1] == 'p'))
114 { strcpy(plugin_copy + plugin_copy_offset, service);
116 plugin_copy_offset += service_len;
119 { plugin_copy[plugin_copy_offset] = plugin[plugin_offset];
121 plugin_copy_offset++;
124 plugin_copy[plugin_copy_len] = 0;
126 argvec = (char **)malloc(s);
129 report(stderr, GT_("fetchmail: malloc failed\n"));
132 memset(argvec, 0, s);
133 for (p = cp = plugin_copy, i = 0; *cp; cp++)
134 { if ((!isspace((unsigned char)*cp)) && (cp == p ? 1 : isspace((unsigned char)*p))) {
140 for (cp = plugin_copy; *cp; cp++)
141 { if (isspace((unsigned char)*cp))
147 static int handle_plugin(const char *host,
148 const char *service, const char *plugin)
149 /* get a socket mediated through a given external command */
155 * The author of this code, Felix von Leitner <felix@convergence.de>, says:
156 * he chose socketpair() instead of pipe() because socketpair creates
157 * bidirectional sockets while allegedly some pipe() implementations don't.
159 if (socketpair(AF_UNIX,SOCK_STREAM,0,fds))
161 report(stderr, GT_("fetchmail: socketpair failed\n"));
167 report(stderr, GT_("fetchmail: fork failed\n"));
170 /* fds[1] is the parent's end; close it for proper EOF
172 (void) close(fds[1]);
173 if ( (dup2(fds[0],0) == -1) || (dup2(fds[0],1) == -1) ) {
174 report(stderr, GT_("dup2 failed\n"));
177 /* fds[0] is now connected to 0 and 1; close it */
178 (void) close(fds[0]);
179 if (outlevel >= O_VERBOSE)
180 report(stderr, GT_("running %s (host %s service %s)\n"), plugin, host, service);
181 argvec = parse_plugin(plugin,host,service);
182 execvp(*argvec, argvec);
183 report(stderr, GT_("execvp(%s) failed\n"), *argvec);
186 default: /* parent */
190 /* fds[0] is the child's end; close it for proper EOF detection */
191 (void) close(fds[0]);
194 #endif /* HAVE_SOCKETPAIR */
198 int SockCheckOpen(int fd)
199 /* poll given socket; is it selectable? */
207 FD_ZERO(&r); FD_ZERO(&w); FD_ZERO(&e);
210 tv.tv_sec = 0; tv.tv_usec = 0;
211 rt = select(fd+1, &r, &w, &e, &tv);
212 if (rt == -1 && (errno != EAGAIN && errno != EINTR))
218 #endif /* __UNUSED__ */
220 int UnixOpen(const char *path)
223 struct sockaddr_un ad;
224 memset(&ad, 0, sizeof(ad));
225 ad.sun_family = AF_UNIX;
226 strncpy(ad.sun_path, path, sizeof(ad.sun_path)-1);
228 sock = socket( AF_UNIX, SOCK_STREAM, 0 );
235 /* Socket opened saved. Usefull if connect timeout
236 * because it can be closed.
238 mailserver_socket_temp = sock;
240 if (connect(sock, (struct sockaddr *) &ad, sizeof(ad)) < 0)
243 fm_close(sock); /* don't use SockClose, no traffic yet */
249 /* No connect timeout, then no need to set mailserver_socket_temp */
250 mailserver_socket_temp = -1;
255 int SockOpen(const char *host, const char *service,
256 const char *plugin, struct addrinfo **ai0)
258 struct addrinfo *ai, req;
261 char errbuf[8192] = "";
263 #ifdef HAVE_SOCKETPAIR
265 return handle_plugin(host,service,plugin);
266 #endif /* HAVE_SOCKETPAIR */
268 memset(&req, 0, sizeof(struct addrinfo));
269 req.ai_socktype = SOCK_STREAM;
271 req.ai_flags = AI_ADDRCONFIG;
274 i = fm_getaddrinfo(host, service, &req, ai0);
276 report(stderr, GT_("getaddrinfo(\"%s\",\"%s\") error: %s\n"),
277 host, service, gai_strerror(i));
278 if (i == EAI_SERVICE)
279 report(stderr, GT_("Try adding the --service option (see also FAQ item R12).\n"));
283 /* NOTE a Linux bug here - getaddrinfo will happily return 127.0.0.1
284 * twice if no IPv6 is configured */
286 for (ord = 0, ai = *ai0; ai; ord++, ai = ai->ai_next) {
287 char buf[256]; /* hostname */
288 char pb[256]; /* service name */
289 int gnie; /* getnameinfo result code */
291 gnie = getnameinfo(ai->ai_addr, ai->ai_addrlen, buf, sizeof(buf), NULL, 0, NI_NUMERICHOST);
293 snprintf(buf, sizeof(buf), GT_("unknown (%s)"), gai_strerror(gnie));
294 gnie = getnameinfo(ai->ai_addr, ai->ai_addrlen, NULL, 0, pb, sizeof(pb), NI_NUMERICSERV);
296 snprintf(pb, sizeof(pb), GT_("unknown (%s)"), gai_strerror(gnie));
298 if (outlevel >= O_VERBOSE)
299 report_build(stdout, GT_("Trying to connect to %s/%s..."), buf, pb);
300 i = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
303 /* mask EAFNOSUPPORT errors, they confuse users for
304 * multihomed hosts */
305 if (errno != EAFNOSUPPORT)
307 if (outlevel >= O_VERBOSE)
308 report_complete(stdout, GT_("cannot create socket: %s\n"), strerror(e));
309 snprintf(errbuf+strlen(errbuf), sizeof(errbuf)-strlen(errbuf),\
310 GT_("name %d: cannot create socket family %d type %d: %s\n"), ord, ai->ai_family, ai->ai_socktype, strerror(e));
314 /* Save socket descriptor.
315 * Used to close the socket after connect timeout. */
316 mailserver_socket_temp = i;
318 if (connect(i, (struct sockaddr *) ai->ai_addr, ai->ai_addrlen) < 0) {
321 /* additionally, suppress IPv4 network unreach errors */
322 if (e != EAFNOSUPPORT)
325 if (outlevel >= O_VERBOSE)
326 report_complete(stdout, GT_("connection failed.\n"));
327 if (outlevel >= O_VERBOSE)
328 report(stderr, GT_("connection to %s:%s [%s/%s] failed: %s.\n"), host, service, buf, pb, strerror(e));
329 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));
334 if (outlevel >= O_VERBOSE)
335 report_complete(stdout, GT_("connected.\n"));
338 /* No connect timeout, then no need to set mailserver_socket_temp */
339 mailserver_socket_temp = -1;
344 fm_freeaddrinfo(*ai0);
348 report(stderr, GT_("Connection errors for this poll:\n%s"), errbuf);
356 #if defined(HAVE_STDARG_H)
357 int SockPrintf(int sock, const char* format, ...)
360 int SockPrintf(sock,format,va_alist)
369 #if defined(HAVE_STDARG_H)
370 va_start(ap, format) ;
374 vsnprintf(buf, sizeof(buf), format, ap);
376 return SockWrite(sock, buf, strlen(buf));
381 #include <openssl/ssl.h>
382 #include <openssl/err.h>
383 #include <openssl/pem.h>
384 #include <openssl/x509v3.h>
385 #include <openssl/rand.h>
387 static SSL_CTX *_ctx[FD_SETSIZE];
388 static SSL *_ssl_context[FD_SETSIZE];
390 static SSL *SSLGetContext( int );
391 #endif /* SSL_ENABLE */
393 int SockWrite(int sock, const char *buf, int len)
403 if( NULL != ( ssl = SSLGetContext( sock ) ) )
404 n = SSL_write(ssl, buf, len);
406 #endif /* SSL_ENABLE */
407 n = fm_write(sock, buf, len);
417 int SockRead(int sock, char *buf, int len)
419 char *newline, *bp = buf;
429 * The reason for these gymnastics is that we want two things:
430 * (1) to read \n-terminated lines,
431 * (2) to return the true length of data read, even if the
432 * data coming in has embedded NULS.
435 if( NULL != ( ssl = SSLGetContext( sock ) ) ) {
437 /* OK... SSL_peek works a little different from MSG_PEEK
438 Problem is that SSL_peek can return 0 if there
439 is no data currently available. If, on the other
440 hand, we loose the socket, we also get a zero, but
441 the SSL_read then SEGFAULTS! To deal with this,
442 we'll check the error code any time we get a return
443 of zero from SSL_peek. If we have an error, we bail.
444 If we don't, we read one character in SSL_read and
445 loop. This should continue to work even if they
446 later change the behavior of SSL_peek
447 to "fix" this problem... :-( */
448 if ((n = SSL_peek(ssl, bp, len)) < 0) {
449 (void)SSL_get_error(ssl, n);
453 /* SSL_peek says no data... Does he mean no data
454 or did the connection blow up? If we got an error
456 if (0 != SSL_get_error(ssl, n)) {
459 /* We didn't get an error so read at least one
460 character at this point and loop */
462 /* Make sure newline start out NULL!
463 * We don't have a string to pass through
464 * the strchr at this point yet */
466 } else if ((newline = (char *)memchr(bp, '\n', n)) != NULL)
467 n = newline - bp + 1;
468 /* Matthias Andree: SSL_read can return 0, in that case
469 * we must call SSL_get_error to figure if there was
470 * an error or just a "no data" condition */
471 if ((n = SSL_read(ssl, bp, n)) <= 0) {
472 if ((n = SSL_get_error(ssl, n))) {
476 /* Check for case where our single character turned out to
477 * be a newline... (It wasn't going to get caught by
478 * the strchr above if it came from the hack... ). */
479 if( NULL == newline && 1 == n && '\n' == *bp ) {
480 /* Got our newline - this will break
481 out of the loop now */
486 #endif /* SSL_ENABLE */
489 if ((n = fm_peek(sock, bp, len)) <= 0)
491 if ((newline = (char *)memchr(bp, '\n', n)) != NULL)
492 n = newline - bp + 1;
493 if ((n = fm_read(sock, bp, n)) == -1)
505 int SockPeek(int sock)
506 /* peek at the next socket character without actually reading it */
515 if( NULL != ( ssl = SSLGetContext( sock ) ) ) {
516 n = SSL_peek(ssl, &ch, 1);
518 (void)SSL_get_error(ssl, n);
522 /* This code really needs to implement a "hold back"
523 * to simulate a functioning SSL_peek()... sigh...
524 * Has to be coordinated with the read code above.
525 * Next on the list todo... */
527 /* SSL_peek says 0... Does that mean no data
528 or did the connection blow up? If we got an error
530 if(0 != SSL_get_error(ssl, n)) {
534 /* Haven't seen this case actually occur, but...
535 if the problem in SockRead can occur, this should
536 be possible... Just not sure what to do here.
537 This should be a safe "punt" the "peek" but don't
538 "punt" the "session"... */
540 return 0; /* Give him a '\0' character */
544 #endif /* SSL_ENABLE */
545 n = fm_peek(sock, &ch, 1);
554 static char *_ssl_server_cname = NULL;
555 static int _check_fp;
556 static char *_check_digest;
557 static char *_server_label;
558 static int _depth0ck;
559 static int _firstrun;
560 static int _prev_err;
561 static int _verify_ok;
563 SSL *SSLGetContext( int sock )
565 if( sock < 0 || (unsigned)sock > FD_SETSIZE )
567 if( _ctx[sock] == NULL )
569 return _ssl_context[sock];
572 /* ok_return (preverify_ok) is 1 if this stage of certificate verification
573 passed, or 0 if it failed. This callback lets us display informative
574 errors, and perform additional validation (e.g. CN matches) */
575 static int SSL_verify_callback( int ok_return, X509_STORE_CTX *ctx, int strict )
577 #define SSLverbose (((outlevel) >= O_DEBUG) || ((outlevel) >= O_VERBOSE && (depth) == 0))
581 unsigned char digest[EVP_MAX_MD_SIZE];
582 char text[EVP_MAX_MD_SIZE * 3 + 1], *tp, *te;
583 const EVP_MD *digest_tp;
584 unsigned int dsz, esz;
585 X509_NAME *subj, *issuer;
588 x509_cert = X509_STORE_CTX_get_current_cert(ctx);
589 err = X509_STORE_CTX_get_error(ctx);
590 depth = X509_STORE_CTX_get_error_depth(ctx);
592 subj = X509_get_subject_name(x509_cert);
593 issuer = X509_get_issuer_name(x509_cert);
595 if (outlevel >= O_VERBOSE) {
596 if (depth == 0 && SSLverbose)
597 report(stderr, GT_("Server certificate:\n"));
602 report(stdout, GT_("Certificate chain, from root to peer, starting at depth %d:\n"), depth);
605 report(stdout, GT_("Certificate at depth %d:\n"), depth);
610 if ((i = X509_NAME_get_text_by_NID(issuer, NID_organizationName, buf, sizeof(buf))) != -1) {
611 report(stdout, GT_("Issuer Organization: %s\n"), (tt = sdump(buf, i)));
613 if ((size_t)i >= sizeof(buf) - 1)
614 report(stdout, GT_("Warning: Issuer Organization Name too long (possibly truncated).\n"));
616 report(stdout, GT_("Unknown Organization\n"));
617 if ((i = X509_NAME_get_text_by_NID(issuer, NID_commonName, buf, sizeof(buf))) != -1) {
618 report(stdout, GT_("Issuer CommonName: %s\n"), (tt = sdump(buf, i)));
620 if ((size_t)i >= sizeof(buf) - 1)
621 report(stdout, GT_("Warning: Issuer CommonName too long (possibly truncated).\n"));
623 report(stdout, GT_("Unknown Issuer CommonName\n"));
627 if ((i = X509_NAME_get_text_by_NID(subj, NID_commonName, buf, sizeof(buf))) != -1) {
629 report(stdout, GT_("Subject CommonName: %s\n"), (tt = sdump(buf, i)));
632 if ((size_t)i >= sizeof(buf) - 1) {
633 /* Possible truncation. In this case, this is a DNS name, so this
634 * is really bad. We do not tolerate this even in the non-strict case. */
635 report(stderr, GT_("Bad certificate: Subject CommonName too long!\n"));
638 if ((size_t)i > strlen(buf)) {
639 /* Name contains embedded NUL characters, so we complain. This is likely
640 * a certificate spoofing attack. */
641 report(stderr, GT_("Bad certificate: Subject CommonName contains NUL, aborting!\n"));
646 if (depth == 0) { /* peer certificate */
651 if ((i = X509_NAME_get_text_by_NID(subj, NID_commonName, buf, sizeof(buf))) != -1) {
652 if (_ssl_server_cname != NULL) {
654 char *p2 = _ssl_server_cname;
656 STACK_OF(GENERAL_NAME) *gens;
658 /* RFC 2595 section 2.4: find a matching name
659 * first find a match among alternative names */
660 gens = (STACK_OF(GENERAL_NAME) *)X509_get_ext_d2i(x509_cert, NID_subject_alt_name, NULL, NULL);
663 for (j = 0, r = sk_GENERAL_NAME_num(gens); j < r; ++j) {
664 const GENERAL_NAME *gn = sk_GENERAL_NAME_value(gens, j);
665 if (gn->type == GEN_DNS) {
666 char *pp1 = (char *)gn->d.ia5->data;
667 char *pp2 = _ssl_server_cname;
668 if (outlevel >= O_VERBOSE) {
669 report(stdout, GT_("Subject Alternative Name: %s\n"), (tt = sdump(pp1, (size_t)gn->d.ia5->length)));
672 /* Name contains embedded NUL characters, so we complain. This
673 * is likely a certificate spoofing attack. */
674 if ((size_t)gn->d.ia5->length != strlen(pp1)) {
675 report(stderr, GT_("Bad certificate: Subject Alternative Name contains NUL, aborting!\n"));
676 sk_GENERAL_NAME_free(gens);
679 if (name_match(pp1, pp2)) {
684 sk_GENERAL_NAME_free(gens);
686 if (name_match(p1, p2)) {
690 if (strict || SSLverbose) {
692 GT_("Server CommonName mismatch: %s != %s\n"),
693 (tt = sdump(buf, i)), _ssl_server_cname );
698 } else if (ok_return) {
699 report(stderr, GT_("Server name not set, could not verify certificate!\n"));
700 if (strict) return (0);
703 if (outlevel >= O_VERBOSE)
704 report(stdout, GT_("Unknown Server CommonName\n"));
705 if (ok_return && strict) {
706 report(stderr, GT_("Server name not specified in certificate!\n"));
710 /* Print the finger print. Note that on errors, we might print it more than once
711 * normally; we kluge around that by using a global variable. */
712 if (_check_fp == 1) {
716 digest_tp = EVP_md5();
717 if (digest_tp == NULL) {
718 report(stderr, GT_("EVP_md5() failed!\n"));
721 if (!X509_digest(x509_cert, digest_tp, digest, &dsz)) {
722 report(stderr, GT_("Out of memory!\n"));
726 te = text + sizeof(text);
727 for (dp = 0; dp < dsz; dp++) {
728 esz = snprintf(tp, te - tp, dp > 0 ? ":%02X" : "%02X", digest[dp]);
729 if (esz >= (size_t)(te - tp)) {
730 report(stderr, GT_("Digest text buffer too small!\n"));
735 if (outlevel > O_NORMAL)
736 report(stdout, GT_("%s key fingerprint: %s\n"), _server_label, text);
737 if (_check_digest != NULL) {
738 if (strcasecmp(text, _check_digest) == 0) {
739 if (outlevel > O_NORMAL)
740 report(stdout, GT_("%s fingerprints match.\n"), _server_label);
742 report(stderr, GT_("%s fingerprints do not match!\n"), _server_label);
745 } /* if (_check_digest != NULL) */
746 } /* if (_check_fp) */
747 } /* if (depth == 0 && !_depth0ck) */
749 if (err != X509_V_OK && err != _prev_err && !(_check_fp != 0 && _check_digest && !strict)) {
752 report(stderr, GT_("Server certificate verification error: %s\n"), X509_verify_cert_error_string(err));
753 /* We gave the error code, but maybe we can add some more details for debugging */
756 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
757 X509_NAME_oneline(issuer, buf, sizeof(buf));
758 buf[sizeof(buf) - 1] = '\0';
759 report(stderr, GT_("unknown issuer (first %d characters): %s\n"), (int)(sizeof(buf)-1), buf);
760 report(stderr, GT_("This error usually happens when the server provides an incomplete certificate "
761 "chain, which is nothing fetchmail could do anything about. For details, "
762 "please see the README.SSL-SERVER document that comes with fetchmail.\n"));
764 case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
765 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY:
766 case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN:
767 X509_NAME_oneline(subj, buf, sizeof(buf));
768 buf[sizeof(buf) - 1] = '\0';
769 report(stderr, GT_("This means that the root signing certificate (issued for %s) is not in the "
770 "trusted CA certificate locations, or that c_rehash needs to be run "
771 "on the certificate directory. For details, please "
772 "see the documentation of --sslcertpath and --sslcertfile in the manual page.\n"), buf);
779 * If not in strict checking mode (--sslcertck), override this
780 * and pretend that verification had succeeded.
782 _verify_ok &= ok_return;
788 static int SSL_nock_verify_callback( int ok_return, X509_STORE_CTX *ctx )
790 return SSL_verify_callback(ok_return, ctx, 0);
793 static int SSL_ck_verify_callback( int ok_return, X509_STORE_CTX *ctx )
795 return SSL_verify_callback(ok_return, ctx, 1);
799 /* get commonName from certificate set in file.
800 * commonName is stored in buffer namebuffer, limited with namebufferlen
802 static const char *SSLCertGetCN(const char *mycert,
803 char *namebuffer, size_t namebufferlen)
805 const char *ret = NULL;
807 X509 *x509_cert = NULL;
808 X509_NAME *certname = NULL;
810 if (namebuffer && namebufferlen > 0) {
811 namebuffer[0] = 0x00;
812 certBio = BIO_new_file(mycert,"r");
814 x509_cert = PEM_read_bio_X509(certBio,NULL,NULL,NULL);
818 certname = X509_get_subject_name(x509_cert);
820 X509_NAME_get_text_by_NID(certname, NID_commonName,
821 namebuffer, namebufferlen) > 0)
823 X509_free(x509_cert);
829 /* performs initial SSL handshake over the connected socket
830 * uses SSL *ssl global variable, which is currently defined
833 int SSLOpen(int sock, char *mycert, char *mykey, const char *myproto, int certck,
834 char *cacertfile, char *certpath,
835 char *fingerprint, char *servercname, char *label, char **remotename)
837 struct stat randstat;
840 SSL_load_error_strings();
842 OpenSSL_add_all_algorithms(); /* see Debian Bug#576430 and manpage */
844 if (stat("/dev/random", &randstat) &&
845 stat("/dev/urandom", &randstat)) {
846 /* Neither /dev/random nor /dev/urandom are present, so add
847 entropy to the SSL PRNG a hard way. */
848 for (i = 0; i < 10000 && ! RAND_status (); ++i) {
851 gettimeofday (&tv, 0);
852 buf[0] = tv.tv_usec & 0xF;
853 buf[2] = (tv.tv_usec & 0xF0) >> 4;
854 buf[3] = (tv.tv_usec & 0xF00) >> 8;
855 buf[1] = (tv.tv_usec & 0xF000) >> 12;
856 RAND_add (buf, sizeof buf, 0.1);
860 if( sock < 0 || (unsigned)sock > FD_SETSIZE ) {
861 report(stderr, GT_("File descriptor out of range for SSL") );
865 /* Make sure a connection referring to an older context is not left */
866 _ssl_context[sock] = NULL;
868 if(!strcasecmp("ssl2",myproto)) {
869 _ctx[sock] = SSL_CTX_new(SSLv2_client_method());
870 } else if(!strcasecmp("ssl3",myproto)) {
871 _ctx[sock] = SSL_CTX_new(SSLv3_client_method());
872 } else if(!strcasecmp("tls1",myproto)) {
873 _ctx[sock] = SSL_CTX_new(TLSv1_client_method());
874 } else if (!strcasecmp("ssl23",myproto)) {
877 fprintf(stderr,GT_("Invalid SSL protocol '%s' specified, using default (SSLv23).\n"), myproto);
882 _ctx[sock] = SSL_CTX_new(SSLv23_client_method());
884 if(_ctx[sock] == NULL) {
885 ERR_print_errors_fp(stderr);
889 SSL_CTX_set_options(_ctx[sock], SSL_OP_ALL);
892 SSL_CTX_set_verify(_ctx[sock], SSL_VERIFY_PEER, SSL_ck_verify_callback);
894 /* In this case, we do not fail if verification fails. However,
895 * we provide the callback for output and possible fingerprint
897 SSL_CTX_set_verify(_ctx[sock], SSL_VERIFY_PEER, SSL_nock_verify_callback);
900 /* Check which trusted X.509 CA certificate store(s) to load */
903 int want_default_cacerts = 0;
905 /* Load user locations if any is given */
906 if (certpath || cacertfile)
907 SSL_CTX_load_verify_locations(_ctx[sock],
908 cacertfile, certpath);
910 want_default_cacerts = 1;
912 tmp = getenv("FETCHMAIL_INCLUDE_DEFAULT_X509_CA_CERTS");
913 if (want_default_cacerts || (tmp && tmp[0])) {
914 SSL_CTX_set_default_verify_paths(_ctx[sock]);
918 _ssl_context[sock] = SSL_new(_ctx[sock]);
920 if(_ssl_context[sock] == NULL) {
921 ERR_print_errors_fp(stderr);
922 SSL_CTX_free(_ctx[sock]);
927 /* This static is for the verify callback */
928 _ssl_server_cname = servercname;
929 _server_label = label;
931 _check_digest = fingerprint;
937 if( mycert || mykey ) {
939 /* Ok... He has a certificate file defined, so lets declare it. If
940 * he does NOT have a separate certificate and private key file then
941 * assume that it's a combined key and certificate file.
950 if ((!*remotename || !**remotename) && SSLCertGetCN(mycert, buffer, sizeof(buffer))) {
952 *remotename = xstrdup(buffer);
954 SSL_use_certificate_file(_ssl_context[sock], mycert, SSL_FILETYPE_PEM);
955 SSL_use_RSAPrivateKey_file(_ssl_context[sock], mykey, SSL_FILETYPE_PEM);
958 if (SSL_set_fd(_ssl_context[sock], sock) == 0
959 || SSL_connect(_ssl_context[sock]) < 1) {
960 ERR_print_errors_fp(stderr);
961 SSL_free( _ssl_context[sock] );
962 _ssl_context[sock] = NULL;
963 SSL_CTX_free(_ctx[sock]);
968 /* Paranoia: was the callback not called as we expected? */
970 report(stderr, GT_("Certificate/fingerprint verification was somehow skipped!\n"));
972 if (fingerprint != NULL || certck) {
973 if( NULL != SSLGetContext( sock ) ) {
974 /* Clean up the SSL stack */
975 SSL_shutdown( _ssl_context[sock] );
976 SSL_free( _ssl_context[sock] );
977 _ssl_context[sock] = NULL;
978 SSL_CTX_free(_ctx[sock]);
985 if (!certck && !fingerprint &&
986 (SSL_get_verify_result(_ssl_context[sock]) != X509_V_OK || !_verify_ok)) {
987 report(stderr, GT_("Warning: the connection is insecure, continuing anyways. (Better use --sslcertck!)\n"));
994 int SockClose(int sock)
995 /* close a socket gracefully */
998 if( NULL != SSLGetContext( sock ) ) {
999 /* Clean up the SSL stack */
1000 SSL_shutdown( _ssl_context[sock] );
1001 SSL_free( _ssl_context[sock] );
1002 _ssl_context[sock] = NULL;
1003 SSL_CTX_free(_ctx[sock]);
1010 * This hangs in RedHat 6.2 after fetchmail runs for a while a
1011 * FIN_WAIT2 comes up in netstat and fetchmail never returns from
1012 * the recv system call. (Reported from jtnews
1013 * <jtnews@bellatlantic.net>, Wed, 24 May 2000 21:26:02.)
1015 * Half-close the connection first so the other end gets notified.
1017 * This stops sends but allows receives (effectively, it sends a
1019 if (shutdown(sock, 1) == 0) {
1021 /* If there is any data still waiting in the queue, discard it.
1022 * Call recv() until either it returns 0 (meaning we received a FIN)
1023 * or any error occurs. This makes sure all data sent by the other
1024 * side is acknowledged at the TCP level.
1026 if (fm_peek(sock, &ch, 1) > 0)
1027 while (fm_read(sock, &ch, 1) > 0)
1030 #endif /* __UNUSED__ */
1032 /* if there's an error closing at this point, not much we can do */
1033 return(fm_close(sock)); /* this is guarded */
1038 * Workaround Microsoft Winsock recv/WSARecv(..., MSG_PEEK) bug.
1039 * See http://sources.redhat.com/ml/cygwin/2001-08/msg00628.html
1042 static ssize_t cygwin_read(int sock, void *buf, size_t count)
1047 if ((n = read(sock, bp, count)) == (size_t)-1)
1052 if (outlevel >= O_VERBOSE)
1053 report(stdout, GT_("Cygwin socket read retry\n"));
1054 n2 = read(sock, bp + n, count - n);
1055 if (n2 == (size_t)-1 || n + n2 != count) {
1056 report(stderr, GT_("Cygwin socket read retry failed!\n"));
1063 #endif /* __CYGWIN__ */
1067 * Use the chargen service to test input buffering directly.
1068 * You may have to uncomment the `chargen' service description in your
1069 * inetd.conf (and then SIGHUP inetd) for this to work. */
1072 int sock = SockOpen("localhost", "chargen", NULL);
1075 while (SockRead(sock, buf, sizeof(buf)-1))
1076 SockWrite(1, buf, strlen(buf));
1081 /* socket.c ends here */