1 /* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
4 * We are making the OpenFlow specification and associated documentation
5 * (Software) available for public use and benefit with the expectation
6 * that others will use, modify and enhance the Software and contribute
7 * those enhancements back to the community. However, since we would
8 * like to make the Software available for broadest use, with as few
9 * restrictions as possible permission is hereby granted, free of
10 * charge, to any person obtaining a copy of this Software to deal in
11 * the Software under the copyrights without restriction, including
12 * without limitation the rights to use, copy, modify, merge, publish,
13 * distribute, sublicense, and/or sell copies of the Software, and to
14 * permit persons to whom the Software is furnished to do so, subject to
15 * the following conditions:
17 * The above copyright notice and this permission notice shall be
18 * included in all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
24 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
25 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
26 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 * The name and trademarks of copyright holder(s) may NOT be used in
30 * advertising or publicity pertaining to the Software or any
31 * derivatives without specific, written prior permission.
35 #include "vconn-ssl.h"
42 #include <netinet/tcp.h>
43 #include <openssl/err.h>
44 #include <openssl/ssl.h>
45 #include <openssl/x509v3.h>
47 #include <sys/fcntl.h>
50 #include "dynamic-string.h"
54 #include "poll-loop.h"
55 #include "socket-util.h"
56 #include "socket-util.h"
58 #include "vconn-provider.h"
62 #define THIS_MODULE VLM_vconn_ssl
81 enum session_type type;
86 struct poll_waiter *tx_waiter;
88 /* rx_want and tx_want record the result of the last call to SSL_read()
89 * and SSL_write(), respectively:
91 * - If the call reported that data needed to be read from the file
92 * descriptor, the corresponding member is set to SSL_READING.
94 * - If the call reported that data needed to be written to the file
95 * descriptor, the corresponding member is set to SSL_WRITING.
97 * - Otherwise, the member is set to SSL_NOTHING, indicating that the
98 * call completed successfully (or with an error) and that there is no
101 * These are needed because there is no way to ask OpenSSL what a data read
102 * or write would require without giving it a buffer to receive into or
103 * data to send, respectively. (Note that the SSL_want() status is
104 * overwritten by each SSL_read() or SSL_write() call, so we can't rely on
107 * A single call to SSL_read() or SSL_write() can perform both reading
108 * and writing and thus invalidate not one of these values but actually
109 * both. Consider this situation, for example:
111 * - SSL_write() blocks on a read, so tx_want gets SSL_READING.
113 * - SSL_read() laters succeeds reading from 'fd' and clears out the
114 * whole receive buffer, so rx_want gets SSL_READING.
116 * - Client calls vconn_wait(WAIT_RECV) and vconn_wait(WAIT_SEND) and
119 * - Now we're stuck blocking until the peer sends us data, even though
120 * SSL_write() could now succeed, which could easily be a deadlock
123 * On the other hand, we can't reset both tx_want and rx_want on every call
124 * to SSL_read() or SSL_write(), because that would produce livelock,
125 * e.g. in this situation:
127 * - SSL_write() blocks, so tx_want gets SSL_READING or SSL_WRITING.
129 * - SSL_read() blocks, so rx_want gets SSL_READING or SSL_WRITING,
130 * but tx_want gets reset to SSL_NOTHING.
132 * - Client calls vconn_wait(WAIT_RECV) and vconn_wait(WAIT_SEND) and
135 * - Client wakes up immediately since SSL_NOTHING in tx_want indicates
136 * that no blocking is necessary.
138 * The solution we adopt here is to set tx_want to SSL_NOTHING after
139 * calling SSL_read() only if the SSL state of the connection changed,
140 * which indicates that an SSL-level renegotiation made some progress, and
141 * similarly for rx_want and SSL_write(). This prevents both the
142 * deadlock and livelock situations above.
144 int rx_want, tx_want;
147 /* SSL context created by ssl_init(). */
150 /* Required configuration. */
151 static bool has_private_key, has_certificate, has_ca_cert;
153 /* Ordinarily, we require a CA certificate for the peer to be locally
154 * available. 'has_ca_cert' is true when this is the case, and neither of the
155 * following variables matter.
157 * We can, however, bootstrap the CA certificate from the peer at the beginning
158 * of our first connection then use that certificate on all subsequent
159 * connections, saving it to a file for use in future runs also. In this case,
160 * 'has_ca_cert' is false, 'bootstrap_ca_cert' is true, and 'ca_cert_file'
161 * names the file to be saved. */
162 static bool bootstrap_ca_cert;
163 static char *ca_cert_file;
165 /* Who knows what can trigger various SSL errors, so let's throttle them down
167 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(10, 25);
169 static int ssl_init(void);
170 static int do_ssl_init(void);
171 static bool ssl_wants_io(int ssl_error);
172 static void ssl_close(struct vconn *);
173 static int interpret_ssl_error(const char *function, int ret, int error,
175 static void ssl_tx_poll_callback(int fd, short int revents, void *vconn_);
176 static DH *tmp_dh_callback(SSL *ssl, int is_export UNUSED, int keylength);
177 static void log_ca_cert(const char *file_name, X509 *cert);
180 want_to_poll_events(int want)
198 new_ssl_vconn(const char *name, int fd, enum session_type type,
199 enum ssl_state state, const struct sockaddr_in *sin,
200 struct vconn **vconnp)
202 struct ssl_vconn *sslv;
207 /* Check for all the needful configuration. */
208 if (!has_private_key) {
209 VLOG_ERR("Private key must be configured to use SSL");
212 if (!has_certificate) {
213 VLOG_ERR("Certificate must be configured to use SSL");
216 if (!has_ca_cert && !bootstrap_ca_cert) {
217 VLOG_ERR("CA certificate must be configured to use SSL");
220 if (!SSL_CTX_check_private_key(ctx)) {
221 VLOG_ERR("Private key does not match certificate public key: %s",
222 ERR_error_string(ERR_get_error(), NULL));
227 retval = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on);
229 VLOG_ERR("%s: setsockopt(TCP_NODELAY): %s", name, strerror(errno));
234 /* Create and configure OpenSSL stream. */
237 VLOG_ERR("SSL_new: %s", ERR_error_string(ERR_get_error(), NULL));
241 if (SSL_set_fd(ssl, fd) == 0) {
242 VLOG_ERR("SSL_set_fd: %s", ERR_error_string(ERR_get_error(), NULL));
245 if (bootstrap_ca_cert && type == CLIENT) {
246 SSL_set_verify(ssl, SSL_VERIFY_NONE, NULL);
249 /* Create and return the ssl_vconn. */
250 sslv = xmalloc(sizeof *sslv);
251 vconn_init(&sslv->vconn, &ssl_vconn_class, EAGAIN, sin->sin_addr.s_addr,
259 sslv->tx_waiter = NULL;
260 sslv->rx_want = sslv->tx_want = SSL_NOTHING;
261 *vconnp = &sslv->vconn;
272 static struct ssl_vconn *
273 ssl_vconn_cast(struct vconn *vconn)
275 vconn_assert_class(vconn, &ssl_vconn_class);
276 return CONTAINER_OF(vconn, struct ssl_vconn, vconn);
280 ssl_open(const char *name, char *suffix, struct vconn **vconnp)
282 char *save_ptr, *host_name, *port_string;
283 struct sockaddr_in sin;
292 /* Glibc 2.7 has a bug in strtok_r when compiling with optimization that
293 * can cause segfaults here:
294 * http://sources.redhat.com/bugzilla/show_bug.cgi?id=5614.
295 * Using "::" instead of the obvious ":" works around it. */
296 host_name = strtok_r(suffix, "::", &save_ptr);
297 port_string = strtok_r(NULL, "::", &save_ptr);
299 ofp_error(0, "%s: bad peer name format", name);
303 memset(&sin, 0, sizeof sin);
304 sin.sin_family = AF_INET;
305 if (lookup_ip(host_name, &sin.sin_addr)) {
308 sin.sin_port = htons(port_string && *port_string ? atoi(port_string)
312 fd = socket(AF_INET, SOCK_STREAM, 0);
314 VLOG_ERR("%s: socket: %s", name, strerror(errno));
317 retval = set_nonblocking(fd);
323 /* Connect socket. */
324 retval = connect(fd, (struct sockaddr *) &sin, sizeof sin);
326 if (errno == EINPROGRESS) {
327 return new_ssl_vconn(name, fd, CLIENT, STATE_TCP_CONNECTING,
331 VLOG_ERR("%s: connect: %s", name, strerror(error));
336 return new_ssl_vconn(name, fd, CLIENT, STATE_SSL_CONNECTING,
342 do_ca_cert_bootstrap(struct vconn *vconn)
344 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
345 STACK_OF(X509) *chain;
351 chain = SSL_get_peer_cert_chain(sslv->ssl);
352 if (!chain || !sk_X509_num(chain)) {
353 VLOG_ERR("could not bootstrap CA cert: no certificate presented by "
357 ca_cert = sk_X509_value(chain, sk_X509_num(chain) - 1);
359 /* Check that 'ca_cert' is self-signed. Otherwise it is not a CA
360 * certificate and we should not attempt to use it as one. */
361 error = X509_check_issued(ca_cert, ca_cert);
363 VLOG_ERR("could not bootstrap CA cert: obtained certificate is "
364 "not self-signed (%s)",
365 X509_verify_cert_error_string(error));
366 if (sk_X509_num(chain) < 2) {
367 VLOG_ERR("only one certificate was received, so probably the peer "
368 "is not configured to send its CA certificate");
373 fd = open(ca_cert_file, O_CREAT | O_EXCL | O_WRONLY, 0444);
375 VLOG_ERR("could not bootstrap CA cert: creating %s failed: %s",
376 ca_cert_file, strerror(errno));
380 file = fdopen(fd, "w");
383 VLOG_ERR("could not bootstrap CA cert: fdopen failed: %s",
385 unlink(ca_cert_file);
389 if (!PEM_write_X509(file, ca_cert)) {
390 VLOG_ERR("could not bootstrap CA cert: PEM_write_X509 to %s failed: "
391 "%s", ca_cert_file, ERR_error_string(ERR_get_error(), NULL));
393 unlink(ca_cert_file);
399 VLOG_ERR("could not bootstrap CA cert: writing %s failed: %s",
400 ca_cert_file, strerror(error));
401 unlink(ca_cert_file);
405 VLOG_WARN("successfully bootstrapped CA cert to %s", ca_cert_file);
406 log_ca_cert(ca_cert_file, ca_cert);
407 bootstrap_ca_cert = false;
410 /* SSL_CTX_add_client_CA makes a copy of ca_cert's relevant data. */
411 SSL_CTX_add_client_CA(ctx, ca_cert);
413 /* SSL_CTX_use_certificate() takes ownership of the certificate passed in.
414 * 'ca_cert' is owned by sslv->ssl, so we need to duplicate it. */
415 ca_cert = X509_dup(ca_cert);
419 if (SSL_CTX_load_verify_locations(ctx, ca_cert_file, NULL) != 1) {
420 VLOG_ERR("SSL_CTX_load_verify_locations: %s",
421 ERR_error_string(ERR_get_error(), NULL));
424 VLOG_WARN("killing successful connection to retry using CA cert");
429 ssl_connect(struct vconn *vconn)
431 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
434 switch (sslv->state) {
435 case STATE_TCP_CONNECTING:
436 retval = check_connection_completion(sslv->fd);
440 sslv->state = STATE_SSL_CONNECTING;
443 case STATE_SSL_CONNECTING:
444 retval = (sslv->type == CLIENT
445 ? SSL_connect(sslv->ssl) : SSL_accept(sslv->ssl));
447 int error = SSL_get_error(sslv->ssl, retval);
448 if (retval < 0 && ssl_wants_io(error)) {
452 interpret_ssl_error((sslv->type == CLIENT ? "SSL_connect"
453 : "SSL_accept"), retval, error, &unused);
454 shutdown(sslv->fd, SHUT_RDWR);
457 } else if (bootstrap_ca_cert) {
458 return do_ca_cert_bootstrap(vconn);
459 } else if ((SSL_get_verify_mode(sslv->ssl)
460 & (SSL_VERIFY_NONE | SSL_VERIFY_PEER))
461 != SSL_VERIFY_PEER) {
462 /* Two or more SSL connections completed at the same time while we
463 * were in bootstrap mode. Only one of these can finish the
464 * bootstrap successfully. The other one(s) must be rejected
465 * because they were not verified against the bootstrapped CA
466 * certificate. (Alternatively we could verify them against the CA
467 * certificate, but that's more trouble than it's worth. These
468 * connections will succeed the next time they retry, assuming that
469 * they have a certificate against the correct CA.) */
470 VLOG_ERR("rejecting SSL connection during bootstrap race window");
481 ssl_close(struct vconn *vconn)
483 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
484 poll_cancel(sslv->tx_waiter);
491 interpret_ssl_error(const char *function, int ret, int error,
498 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_NONE", function);
501 case SSL_ERROR_ZERO_RETURN:
502 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_ZERO_RETURN", function);
505 case SSL_ERROR_WANT_READ:
509 case SSL_ERROR_WANT_WRITE:
513 case SSL_ERROR_WANT_CONNECT:
514 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_CONNECT", function);
517 case SSL_ERROR_WANT_ACCEPT:
518 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_ACCEPT", function);
521 case SSL_ERROR_WANT_X509_LOOKUP:
522 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_X509_LOOKUP",
526 case SSL_ERROR_SYSCALL: {
527 int queued_error = ERR_get_error();
528 if (queued_error == 0) {
531 VLOG_WARN_RL(&rl, "%s: system error (%s)",
532 function, strerror(status));
535 VLOG_WARN_RL(&rl, "%s: unexpected SSL connection close",
540 VLOG_WARN_RL(&rl, "%s: %s",
541 function, ERR_error_string(queued_error, NULL));
546 case SSL_ERROR_SSL: {
547 int queued_error = ERR_get_error();
548 if (queued_error != 0) {
549 VLOG_WARN_RL(&rl, "%s: %s",
550 function, ERR_error_string(queued_error, NULL));
552 VLOG_ERR_RL(&rl, "%s: SSL_ERROR_SSL without queued error",
559 VLOG_ERR_RL(&rl, "%s: bad SSL error code %d", function, error);
566 ssl_recv(struct vconn *vconn, struct ofpbuf **bufferp)
568 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
574 if (sslv->rxbuf == NULL) {
575 sslv->rxbuf = ofpbuf_new(1564);
580 if (sizeof(struct ofp_header) > rx->size) {
581 want_bytes = sizeof(struct ofp_header) - rx->size;
583 struct ofp_header *oh = rx->data;
584 size_t length = ntohs(oh->length);
585 if (length < sizeof(struct ofp_header)) {
586 VLOG_ERR_RL(&rl, "received too-short ofp_header (%zu bytes)",
590 want_bytes = length - rx->size;
597 ofpbuf_prealloc_tailroom(rx, want_bytes);
599 /* Behavior of zero-byte SSL_read is poorly defined. */
600 assert(want_bytes > 0);
602 old_state = SSL_get_state(sslv->ssl);
603 ret = SSL_read(sslv->ssl, ofpbuf_tail(rx), want_bytes);
604 if (old_state != SSL_get_state(sslv->ssl)) {
605 sslv->tx_want = SSL_NOTHING;
606 if (sslv->tx_waiter) {
607 poll_cancel(sslv->tx_waiter);
608 ssl_tx_poll_callback(sslv->fd, POLLIN, vconn);
611 sslv->rx_want = SSL_NOTHING;
615 if (ret == want_bytes) {
616 if (rx->size > sizeof(struct ofp_header)) {
626 int error = SSL_get_error(sslv->ssl, ret);
627 if (error == SSL_ERROR_ZERO_RETURN) {
628 /* Connection closed (EOF). */
630 VLOG_WARN_RL(&rl, "SSL_read: unexpected connection close");
636 return interpret_ssl_error("SSL_read", ret, error, &sslv->rx_want);
642 ssl_clear_txbuf(struct ssl_vconn *sslv)
644 ofpbuf_delete(sslv->txbuf);
646 sslv->tx_waiter = NULL;
650 ssl_register_tx_waiter(struct vconn *vconn)
652 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
653 sslv->tx_waiter = poll_fd_callback(sslv->fd,
654 want_to_poll_events(sslv->tx_want),
655 ssl_tx_poll_callback, vconn);
659 ssl_do_tx(struct vconn *vconn)
661 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
664 int old_state = SSL_get_state(sslv->ssl);
665 int ret = SSL_write(sslv->ssl, sslv->txbuf->data, sslv->txbuf->size);
666 if (old_state != SSL_get_state(sslv->ssl)) {
667 sslv->rx_want = SSL_NOTHING;
669 sslv->tx_want = SSL_NOTHING;
671 ofpbuf_pull(sslv->txbuf, ret);
672 if (sslv->txbuf->size == 0) {
676 int ssl_error = SSL_get_error(sslv->ssl, ret);
677 if (ssl_error == SSL_ERROR_ZERO_RETURN) {
678 VLOG_WARN_RL(&rl, "SSL_write: connection closed");
681 return interpret_ssl_error("SSL_write", ret, ssl_error,
689 ssl_tx_poll_callback(int fd UNUSED, short int revents UNUSED, void *vconn_)
691 struct vconn *vconn = vconn_;
692 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
693 int error = ssl_do_tx(vconn);
694 if (error != EAGAIN) {
695 ssl_clear_txbuf(sslv);
697 ssl_register_tx_waiter(vconn);
702 ssl_send(struct vconn *vconn, struct ofpbuf *buffer)
704 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
711 sslv->txbuf = buffer;
712 error = ssl_do_tx(vconn);
715 ssl_clear_txbuf(sslv);
718 ssl_register_tx_waiter(vconn);
728 ssl_wait(struct vconn *vconn, enum vconn_wait_type wait)
730 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
734 if (vconn_connect(vconn) != EAGAIN) {
735 poll_immediate_wake();
737 switch (sslv->state) {
738 case STATE_TCP_CONNECTING:
739 poll_fd_wait(sslv->fd, POLLOUT);
742 case STATE_SSL_CONNECTING:
743 /* ssl_connect() called SSL_accept() or SSL_connect(), which
744 * set up the status that we test here. */
745 poll_fd_wait(sslv->fd,
746 want_to_poll_events(SSL_want(sslv->ssl)));
756 if (sslv->rx_want != SSL_NOTHING) {
757 poll_fd_wait(sslv->fd, want_to_poll_events(sslv->rx_want));
759 poll_immediate_wake();
765 /* We have room in our tx queue. */
766 poll_immediate_wake();
768 /* The call to ssl_tx_poll_callback() will wake us up. */
777 struct vconn_class ssl_vconn_class = {
780 ssl_close, /* close */
781 ssl_connect, /* connect */
791 struct pvconn pvconn;
795 struct pvconn_class pssl_pvconn_class;
797 static struct pssl_pvconn *
798 pssl_pvconn_cast(struct pvconn *pvconn)
800 pvconn_assert_class(pvconn, &pssl_pvconn_class);
801 return CONTAINER_OF(pvconn, struct pssl_pvconn, pvconn);
805 pssl_open(const char *name, char *suffix, struct pvconn **pvconnp)
807 struct sockaddr_in sin;
808 struct pssl_pvconn *pssl;
811 unsigned int yes = 1;
819 fd = socket(AF_INET, SOCK_STREAM, 0);
822 VLOG_ERR("%s: socket: %s", name, strerror(error));
826 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes) < 0) {
828 VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s", name, strerror(errno));
832 memset(&sin, 0, sizeof sin);
833 sin.sin_family = AF_INET;
834 sin.sin_addr.s_addr = htonl(INADDR_ANY);
835 sin.sin_port = htons(atoi(suffix) ? atoi(suffix) : OFP_SSL_PORT);
836 retval = bind(fd, (struct sockaddr *) &sin, sizeof sin);
839 VLOG_ERR("%s: bind: %s", name, strerror(error));
844 retval = listen(fd, 10);
847 VLOG_ERR("%s: listen: %s", name, strerror(error));
852 retval = set_nonblocking(fd);
858 pssl = xmalloc(sizeof *pssl);
859 pvconn_init(&pssl->pvconn, &pssl_pvconn_class, name);
861 *pvconnp = &pssl->pvconn;
866 pssl_close(struct pvconn *pvconn)
868 struct pssl_pvconn *pssl = pssl_pvconn_cast(pvconn);
874 pssl_accept(struct pvconn *pvconn, struct vconn **new_vconnp)
876 struct pssl_pvconn *pssl = pssl_pvconn_cast(pvconn);
877 struct sockaddr_in sin;
878 socklen_t sin_len = sizeof sin;
883 new_fd = accept(pssl->fd, &sin, &sin_len);
886 if (error != EAGAIN) {
887 VLOG_DBG_RL(&rl, "accept: %s", strerror(error));
892 error = set_nonblocking(new_fd);
898 sprintf(name, "ssl:"IP_FMT, IP_ARGS(&sin.sin_addr));
899 if (sin.sin_port != htons(OFP_SSL_PORT)) {
900 sprintf(strchr(name, '\0'), ":%"PRIu16, ntohs(sin.sin_port));
902 return new_ssl_vconn(name, new_fd, SERVER, STATE_SSL_CONNECTING, &sin,
907 pssl_wait(struct pvconn *pvconn)
909 struct pssl_pvconn *pssl = pssl_pvconn_cast(pvconn);
910 poll_fd_wait(pssl->fd, POLLIN);
913 struct pvconn_class pssl_pvconn_class = {
922 * Returns true if OpenSSL error is WANT_READ or WANT_WRITE, indicating that
923 * OpenSSL is requesting that we call it back when the socket is ready for read
924 * or writing, respectively.
927 ssl_wants_io(int ssl_error)
929 return (ssl_error == SSL_ERROR_WANT_WRITE
930 || ssl_error == SSL_ERROR_WANT_READ);
936 static int init_status = -1;
937 if (init_status < 0) {
938 init_status = do_ssl_init();
939 assert(init_status >= 0);
950 SSL_load_error_strings();
952 method = TLSv1_method();
953 if (method == NULL) {
954 VLOG_ERR("TLSv1_method: %s", ERR_error_string(ERR_get_error(), NULL));
958 ctx = SSL_CTX_new(method);
960 VLOG_ERR("SSL_CTX_new: %s", ERR_error_string(ERR_get_error(), NULL));
963 SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
964 SSL_CTX_set_tmp_dh_callback(ctx, tmp_dh_callback);
965 SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
966 SSL_CTX_set_mode(ctx, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
967 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
974 tmp_dh_callback(SSL *ssl, int is_export UNUSED, int keylength)
979 DH *(*constructor)(void);
982 static struct dh dh_table[] = {
983 {1024, NULL, get_dh1024},
984 {2048, NULL, get_dh2048},
985 {4096, NULL, get_dh4096},
990 for (dh = dh_table; dh < &dh_table[ARRAY_SIZE(dh_table)]; dh++) {
991 if (dh->keylength == keylength) {
993 dh->dh = dh->constructor();
995 ofp_fatal(ENOMEM, "out of memory constructing "
996 "Diffie-Hellman parameters");
1002 VLOG_ERR_RL(&rl, "no Diffie-Hellman parameters for key length %d",
1007 /* Returns true if SSL is at least partially configured. */
1009 vconn_ssl_is_configured(void)
1011 return has_private_key || has_certificate || has_ca_cert;
1015 vconn_ssl_set_private_key_file(const char *file_name)
1020 if (SSL_CTX_use_PrivateKey_file(ctx, file_name, SSL_FILETYPE_PEM) != 1) {
1021 VLOG_ERR("SSL_use_PrivateKey_file: %s",
1022 ERR_error_string(ERR_get_error(), NULL));
1025 has_private_key = true;
1029 vconn_ssl_set_certificate_file(const char *file_name)
1034 if (SSL_CTX_use_certificate_chain_file(ctx, file_name) != 1) {
1035 VLOG_ERR("SSL_use_certificate_file: %s",
1036 ERR_error_string(ERR_get_error(), NULL));
1039 has_certificate = true;
1042 /* Reads the X509 certificate or certificates in file 'file_name'. On success,
1043 * stores the address of the first element in an array of pointers to
1044 * certificates in '*certs' and the number of certificates in the array in
1045 * '*n_certs', and returns 0. On failure, stores a null pointer in '*certs', 0
1046 * in '*n_certs', and returns a positive errno value.
1048 * The caller is responsible for freeing '*certs'. */
1050 read_cert_file(const char *file_name, X509 ***certs, size_t *n_certs)
1053 size_t allocated_certs = 0;
1058 file = fopen(file_name, "r");
1060 VLOG_ERR("failed to open %s for reading: %s",
1061 file_name, strerror(errno));
1069 /* Read certificate from file. */
1070 certificate = PEM_read_X509(file, NULL, NULL, NULL);
1074 VLOG_ERR("PEM_read_X509 failed reading %s: %s",
1075 file_name, ERR_error_string(ERR_get_error(), NULL));
1076 for (i = 0; i < *n_certs; i++) {
1077 X509_free((*certs)[i]);
1085 /* Add certificate to array. */
1086 if (*n_certs >= allocated_certs) {
1087 allocated_certs = 1 + 2 * allocated_certs;
1088 *certs = xrealloc(*certs, sizeof *certs * allocated_certs);
1090 (*certs)[(*n_certs)++] = certificate;
1092 /* Are there additional certificates in the file? */
1095 } while (isspace(c));
1106 /* Sets 'file_name' as the name of a file containing one or more X509
1107 * certificates to send to the peer. Typical use in OpenFlow is to send the CA
1108 * certificate to the peer, which enables a switch to pick up the controller's
1109 * CA certificate on its first connection. */
1111 vconn_ssl_set_peer_ca_cert_file(const char *file_name)
1121 if (!read_cert_file(file_name, &certs, &n_certs)) {
1122 for (i = 0; i < n_certs; i++) {
1123 if (SSL_CTX_add_extra_chain_cert(ctx, certs[i]) != 1) {
1124 VLOG_ERR("SSL_CTX_add_extra_chain_cert: %s",
1125 ERR_error_string(ERR_get_error(), NULL));
1132 /* Logs fingerprint of CA certificate 'cert' obtained from 'file_name'. */
1134 log_ca_cert(const char *file_name, X509 *cert)
1136 unsigned char digest[EVP_MAX_MD_SIZE];
1137 unsigned int n_bytes;
1142 if (!X509_digest(cert, EVP_sha1(), digest, &n_bytes)) {
1143 ds_put_cstr(&fp, "<out of memory>");
1146 for (i = 0; i < n_bytes; i++) {
1148 ds_put_char(&fp, ':');
1150 ds_put_format(&fp, "%02hhx", digest[i]);
1153 subject = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0);
1154 VLOG_WARN("Trusting CA cert from %s (%s) (fingerprint %s)", file_name,
1155 subject ? subject : "<out of memory>", ds_cstr(&fp));
1160 /* Sets 'file_name' as the name of the file from which to read the CA
1161 * certificate used to verify the peer within SSL connections. If 'bootstrap'
1162 * is false, the file must exist. If 'bootstrap' is false, then the file is
1163 * read if it is exists; if it does not, then it will be created from the CA
1164 * certificate received from the peer on the first SSL connection. */
1166 vconn_ssl_set_ca_cert_file(const char *file_name, bool bootstrap)
1176 if (bootstrap && stat(file_name, &s) && errno == ENOENT) {
1177 bootstrap_ca_cert = true;
1178 ca_cert_file = xstrdup(file_name);
1179 } else if (!read_cert_file(file_name, &certs, &n_certs)) {
1182 /* Set up list of CAs that the server will accept from the client. */
1183 for (i = 0; i < n_certs; i++) {
1184 /* SSL_CTX_add_client_CA makes a copy of the relevant data. */
1185 if (SSL_CTX_add_client_CA(ctx, certs[i]) != 1) {
1186 VLOG_ERR("failed to add client certificate %d from %s: %s",
1188 ERR_error_string(ERR_get_error(), NULL));
1190 log_ca_cert(file_name, certs[i]);
1192 X509_free(certs[i]);
1195 /* Set up CAs for OpenSSL to trust in verifying the peer's
1197 if (SSL_CTX_load_verify_locations(ctx, file_name, NULL) != 1) {
1198 VLOG_ERR("SSL_CTX_load_verify_locations: %s",
1199 ERR_error_string(ERR_get_error(), NULL));