2 * Copyright (c) 2008, 2009 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 #include "vconn-ssl.h"
25 #include <netinet/tcp.h>
26 #include <openssl/err.h>
27 #include <openssl/ssl.h>
28 #include <openssl/x509v3.h>
30 #include <sys/fcntl.h>
33 #include "dynamic-string.h"
34 #include "leak-checker.h"
36 #include "openflow/openflow.h"
38 #include "poll-loop.h"
39 #include "socket-util.h"
40 #include "socket-util.h"
42 #include "vconn-provider.h"
46 #define THIS_MODULE VLM_vconn_ssl
65 enum session_type type;
70 struct poll_waiter *tx_waiter;
72 /* rx_want and tx_want record the result of the last call to SSL_read()
73 * and SSL_write(), respectively:
75 * - If the call reported that data needed to be read from the file
76 * descriptor, the corresponding member is set to SSL_READING.
78 * - If the call reported that data needed to be written to the file
79 * descriptor, the corresponding member is set to SSL_WRITING.
81 * - Otherwise, the member is set to SSL_NOTHING, indicating that the
82 * call completed successfully (or with an error) and that there is no
85 * These are needed because there is no way to ask OpenSSL what a data read
86 * or write would require without giving it a buffer to receive into or
87 * data to send, respectively. (Note that the SSL_want() status is
88 * overwritten by each SSL_read() or SSL_write() call, so we can't rely on
91 * A single call to SSL_read() or SSL_write() can perform both reading
92 * and writing and thus invalidate not one of these values but actually
93 * both. Consider this situation, for example:
95 * - SSL_write() blocks on a read, so tx_want gets SSL_READING.
97 * - SSL_read() laters succeeds reading from 'fd' and clears out the
98 * whole receive buffer, so rx_want gets SSL_READING.
100 * - Client calls vconn_wait(WAIT_RECV) and vconn_wait(WAIT_SEND) and
103 * - Now we're stuck blocking until the peer sends us data, even though
104 * SSL_write() could now succeed, which could easily be a deadlock
107 * On the other hand, we can't reset both tx_want and rx_want on every call
108 * to SSL_read() or SSL_write(), because that would produce livelock,
109 * e.g. in this situation:
111 * - SSL_write() blocks, so tx_want gets SSL_READING or SSL_WRITING.
113 * - SSL_read() blocks, so rx_want gets SSL_READING or SSL_WRITING,
114 * but tx_want gets reset to SSL_NOTHING.
116 * - Client calls vconn_wait(WAIT_RECV) and vconn_wait(WAIT_SEND) and
119 * - Client wakes up immediately since SSL_NOTHING in tx_want indicates
120 * that no blocking is necessary.
122 * The solution we adopt here is to set tx_want to SSL_NOTHING after
123 * calling SSL_read() only if the SSL state of the connection changed,
124 * which indicates that an SSL-level renegotiation made some progress, and
125 * similarly for rx_want and SSL_write(). This prevents both the
126 * deadlock and livelock situations above.
128 int rx_want, tx_want;
131 /* SSL context created by ssl_init(). */
134 /* Required configuration. */
135 static bool has_private_key, has_certificate, has_ca_cert;
137 /* Ordinarily, we require a CA certificate for the peer to be locally
138 * available. 'has_ca_cert' is true when this is the case, and neither of the
139 * following variables matter.
141 * We can, however, bootstrap the CA certificate from the peer at the beginning
142 * of our first connection then use that certificate on all subsequent
143 * connections, saving it to a file for use in future runs also. In this case,
144 * 'has_ca_cert' is false, 'bootstrap_ca_cert' is true, and 'ca_cert_file'
145 * names the file to be saved. */
146 static bool bootstrap_ca_cert;
147 static char *ca_cert_file;
149 /* Who knows what can trigger various SSL errors, so let's throttle them down
151 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(10, 25);
153 static int ssl_init(void);
154 static int do_ssl_init(void);
155 static bool ssl_wants_io(int ssl_error);
156 static void ssl_close(struct vconn *);
157 static void ssl_clear_txbuf(struct ssl_vconn *);
158 static int interpret_ssl_error(const char *function, int ret, int error,
160 static void ssl_tx_poll_callback(int fd, short int revents, void *vconn_);
161 static DH *tmp_dh_callback(SSL *ssl, int is_export UNUSED, int keylength);
162 static void log_ca_cert(const char *file_name, X509 *cert);
165 want_to_poll_events(int want)
183 new_ssl_vconn(const char *name, int fd, enum session_type type,
184 enum ssl_state state, const struct sockaddr_in *sin,
185 struct vconn **vconnp)
187 struct ssl_vconn *sslv;
192 /* Check for all the needful configuration. */
194 if (!has_private_key) {
195 VLOG_ERR("Private key must be configured to use SSL");
196 retval = ENOPROTOOPT;
198 if (!has_certificate) {
199 VLOG_ERR("Certificate must be configured to use SSL");
200 retval = ENOPROTOOPT;
202 if (!has_ca_cert && !bootstrap_ca_cert) {
203 VLOG_ERR("CA certificate must be configured to use SSL");
204 retval = ENOPROTOOPT;
206 if (!SSL_CTX_check_private_key(ctx)) {
207 VLOG_ERR("Private key does not match certificate public key: %s",
208 ERR_error_string(ERR_get_error(), NULL));
209 retval = ENOPROTOOPT;
216 retval = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on);
218 VLOG_ERR("%s: setsockopt(TCP_NODELAY): %s", name, strerror(errno));
223 /* Create and configure OpenSSL stream. */
226 VLOG_ERR("SSL_new: %s", ERR_error_string(ERR_get_error(), NULL));
227 retval = ENOPROTOOPT;
230 if (SSL_set_fd(ssl, fd) == 0) {
231 VLOG_ERR("SSL_set_fd: %s", ERR_error_string(ERR_get_error(), NULL));
232 retval = ENOPROTOOPT;
235 if (bootstrap_ca_cert && type == CLIENT) {
236 SSL_set_verify(ssl, SSL_VERIFY_NONE, NULL);
239 /* Create and return the ssl_vconn. */
240 sslv = xmalloc(sizeof *sslv);
241 vconn_init(&sslv->vconn, &ssl_vconn_class, EAGAIN,
242 sin->sin_addr.s_addr, sin->sin_port, name, true);
249 sslv->tx_waiter = NULL;
250 sslv->rx_want = sslv->tx_want = SSL_NOTHING;
251 *vconnp = &sslv->vconn;
262 static struct ssl_vconn *
263 ssl_vconn_cast(struct vconn *vconn)
265 vconn_assert_class(vconn, &ssl_vconn_class);
266 return CONTAINER_OF(vconn, struct ssl_vconn, vconn);
270 ssl_open(const char *name, char *suffix, struct vconn **vconnp)
272 char *save_ptr, *host_name, *port_string;
273 struct sockaddr_in sin;
282 host_name = strtok_r(suffix, ":", &save_ptr);
283 port_string = strtok_r(NULL, ":", &save_ptr);
285 ovs_error(0, "%s: bad peer name format", name);
289 memset(&sin, 0, sizeof sin);
290 sin.sin_family = AF_INET;
291 if (lookup_ip(host_name, &sin.sin_addr)) {
294 sin.sin_port = htons(port_string && *port_string ? atoi(port_string)
298 fd = socket(AF_INET, SOCK_STREAM, 0);
300 VLOG_ERR("%s: socket: %s", name, strerror(errno));
303 retval = set_nonblocking(fd);
309 /* Connect socket. */
310 retval = connect(fd, (struct sockaddr *) &sin, sizeof sin);
312 if (errno == EINPROGRESS) {
313 return new_ssl_vconn(name, fd, CLIENT, STATE_TCP_CONNECTING,
317 VLOG_ERR("%s: connect: %s", name, strerror(error));
322 return new_ssl_vconn(name, fd, CLIENT, STATE_SSL_CONNECTING,
328 do_ca_cert_bootstrap(struct vconn *vconn)
330 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
331 STACK_OF(X509) *chain;
337 chain = SSL_get_peer_cert_chain(sslv->ssl);
338 if (!chain || !sk_X509_num(chain)) {
339 VLOG_ERR("could not bootstrap CA cert: no certificate presented by "
343 ca_cert = sk_X509_value(chain, sk_X509_num(chain) - 1);
345 /* Check that 'ca_cert' is self-signed. Otherwise it is not a CA
346 * certificate and we should not attempt to use it as one. */
347 error = X509_check_issued(ca_cert, ca_cert);
349 VLOG_ERR("could not bootstrap CA cert: obtained certificate is "
350 "not self-signed (%s)",
351 X509_verify_cert_error_string(error));
352 if (sk_X509_num(chain) < 2) {
353 VLOG_ERR("only one certificate was received, so probably the peer "
354 "is not configured to send its CA certificate");
359 fd = open(ca_cert_file, O_CREAT | O_EXCL | O_WRONLY, 0444);
361 VLOG_ERR("could not bootstrap CA cert: creating %s failed: %s",
362 ca_cert_file, strerror(errno));
366 file = fdopen(fd, "w");
369 VLOG_ERR("could not bootstrap CA cert: fdopen failed: %s",
371 unlink(ca_cert_file);
375 if (!PEM_write_X509(file, ca_cert)) {
376 VLOG_ERR("could not bootstrap CA cert: PEM_write_X509 to %s failed: "
377 "%s", ca_cert_file, ERR_error_string(ERR_get_error(), NULL));
379 unlink(ca_cert_file);
385 VLOG_ERR("could not bootstrap CA cert: writing %s failed: %s",
386 ca_cert_file, strerror(error));
387 unlink(ca_cert_file);
391 VLOG_INFO("successfully bootstrapped CA cert to %s", ca_cert_file);
392 log_ca_cert(ca_cert_file, ca_cert);
393 bootstrap_ca_cert = false;
396 /* SSL_CTX_add_client_CA makes a copy of ca_cert's relevant data. */
397 SSL_CTX_add_client_CA(ctx, ca_cert);
399 /* SSL_CTX_use_certificate() takes ownership of the certificate passed in.
400 * 'ca_cert' is owned by sslv->ssl, so we need to duplicate it. */
401 ca_cert = X509_dup(ca_cert);
405 if (SSL_CTX_load_verify_locations(ctx, ca_cert_file, NULL) != 1) {
406 VLOG_ERR("SSL_CTX_load_verify_locations: %s",
407 ERR_error_string(ERR_get_error(), NULL));
410 VLOG_INFO("killing successful connection to retry using CA cert");
415 ssl_connect(struct vconn *vconn)
417 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
420 switch (sslv->state) {
421 case STATE_TCP_CONNECTING:
422 retval = check_connection_completion(sslv->fd);
426 sslv->state = STATE_SSL_CONNECTING;
429 case STATE_SSL_CONNECTING: {
430 struct sockaddr_in local_addr;
431 socklen_t addrlen = sizeof(local_addr);
433 /* Get the local IP and port information */
434 retval = getsockname(sslv->fd, (struct sockaddr *)&local_addr,
437 memset(&local_addr, 0, sizeof local_addr);
439 vconn_set_local_ip(vconn, local_addr.sin_addr.s_addr);
440 vconn_set_local_port(vconn, local_addr.sin_port);
442 retval = (sslv->type == CLIENT
443 ? SSL_connect(sslv->ssl) : SSL_accept(sslv->ssl));
445 int error = SSL_get_error(sslv->ssl, retval);
446 if (retval < 0 && ssl_wants_io(error)) {
450 interpret_ssl_error((sslv->type == CLIENT ? "SSL_connect"
451 : "SSL_accept"), retval, error, &unused);
452 shutdown(sslv->fd, SHUT_RDWR);
455 } else if (bootstrap_ca_cert) {
456 return do_ca_cert_bootstrap(vconn);
457 } else if ((SSL_get_verify_mode(sslv->ssl)
458 & (SSL_VERIFY_NONE | SSL_VERIFY_PEER))
459 != SSL_VERIFY_PEER) {
460 /* Two or more SSL connections completed at the same time while we
461 * were in bootstrap mode. Only one of these can finish the
462 * bootstrap successfully. The other one(s) must be rejected
463 * because they were not verified against the bootstrapped CA
464 * certificate. (Alternatively we could verify them against the CA
465 * certificate, but that's more trouble than it's worth. These
466 * connections will succeed the next time they retry, assuming that
467 * they have a certificate against the correct CA.) */
468 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);
485 ssl_clear_txbuf(sslv);
486 ofpbuf_delete(sslv->rxbuf);
493 interpret_ssl_error(const char *function, int ret, int error,
500 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_NONE", function);
503 case SSL_ERROR_ZERO_RETURN:
504 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_ZERO_RETURN", function);
507 case SSL_ERROR_WANT_READ:
511 case SSL_ERROR_WANT_WRITE:
515 case SSL_ERROR_WANT_CONNECT:
516 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_CONNECT", function);
519 case SSL_ERROR_WANT_ACCEPT:
520 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_ACCEPT", function);
523 case SSL_ERROR_WANT_X509_LOOKUP:
524 VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_X509_LOOKUP",
528 case SSL_ERROR_SYSCALL: {
529 int queued_error = ERR_get_error();
530 if (queued_error == 0) {
533 VLOG_WARN_RL(&rl, "%s: system error (%s)",
534 function, strerror(status));
537 VLOG_WARN_RL(&rl, "%s: unexpected SSL connection close",
542 VLOG_WARN_RL(&rl, "%s: %s",
543 function, ERR_error_string(queued_error, NULL));
548 case SSL_ERROR_SSL: {
549 int queued_error = ERR_get_error();
550 if (queued_error != 0) {
551 VLOG_WARN_RL(&rl, "%s: %s",
552 function, ERR_error_string(queued_error, NULL));
554 VLOG_ERR_RL(&rl, "%s: SSL_ERROR_SSL without queued error",
561 VLOG_ERR_RL(&rl, "%s: bad SSL error code %d", function, error);
568 ssl_recv(struct vconn *vconn, struct ofpbuf **bufferp)
570 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
576 if (sslv->rxbuf == NULL) {
577 sslv->rxbuf = ofpbuf_new(1564);
582 if (sizeof(struct ofp_header) > rx->size) {
583 want_bytes = sizeof(struct ofp_header) - rx->size;
585 struct ofp_header *oh = rx->data;
586 size_t length = ntohs(oh->length);
587 if (length < sizeof(struct ofp_header)) {
588 VLOG_ERR_RL(&rl, "received too-short ofp_header (%zu bytes)",
592 want_bytes = length - rx->size;
599 ofpbuf_prealloc_tailroom(rx, want_bytes);
601 /* Behavior of zero-byte SSL_read is poorly defined. */
602 assert(want_bytes > 0);
604 old_state = SSL_get_state(sslv->ssl);
605 ret = SSL_read(sslv->ssl, ofpbuf_tail(rx), want_bytes);
606 if (old_state != SSL_get_state(sslv->ssl)) {
607 sslv->tx_want = SSL_NOTHING;
608 if (sslv->tx_waiter) {
609 poll_cancel(sslv->tx_waiter);
610 ssl_tx_poll_callback(sslv->fd, POLLIN, vconn);
613 sslv->rx_want = SSL_NOTHING;
617 if (ret == want_bytes) {
618 if (rx->size > sizeof(struct ofp_header)) {
628 int error = SSL_get_error(sslv->ssl, ret);
629 if (error == SSL_ERROR_ZERO_RETURN) {
630 /* Connection closed (EOF). */
632 VLOG_WARN_RL(&rl, "SSL_read: unexpected connection close");
638 return interpret_ssl_error("SSL_read", ret, error, &sslv->rx_want);
644 ssl_clear_txbuf(struct ssl_vconn *sslv)
646 ofpbuf_delete(sslv->txbuf);
648 sslv->tx_waiter = NULL;
652 ssl_register_tx_waiter(struct vconn *vconn)
654 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
655 sslv->tx_waiter = poll_fd_callback(sslv->fd,
656 want_to_poll_events(sslv->tx_want),
657 ssl_tx_poll_callback, vconn);
661 ssl_do_tx(struct vconn *vconn)
663 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
666 int old_state = SSL_get_state(sslv->ssl);
667 int ret = SSL_write(sslv->ssl, sslv->txbuf->data, sslv->txbuf->size);
668 if (old_state != SSL_get_state(sslv->ssl)) {
669 sslv->rx_want = SSL_NOTHING;
671 sslv->tx_want = SSL_NOTHING;
673 ofpbuf_pull(sslv->txbuf, ret);
674 if (sslv->txbuf->size == 0) {
678 int ssl_error = SSL_get_error(sslv->ssl, ret);
679 if (ssl_error == SSL_ERROR_ZERO_RETURN) {
680 VLOG_WARN_RL(&rl, "SSL_write: connection closed");
683 return interpret_ssl_error("SSL_write", ret, ssl_error,
691 ssl_tx_poll_callback(int fd UNUSED, short int revents UNUSED, void *vconn_)
693 struct vconn *vconn = vconn_;
694 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
695 int error = ssl_do_tx(vconn);
696 if (error != EAGAIN) {
697 ssl_clear_txbuf(sslv);
699 ssl_register_tx_waiter(vconn);
704 ssl_send(struct vconn *vconn, struct ofpbuf *buffer)
706 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
713 sslv->txbuf = buffer;
714 error = ssl_do_tx(vconn);
717 ssl_clear_txbuf(sslv);
720 leak_checker_claim(buffer);
721 ssl_register_tx_waiter(vconn);
731 ssl_wait(struct vconn *vconn, enum vconn_wait_type wait)
733 struct ssl_vconn *sslv = ssl_vconn_cast(vconn);
737 if (vconn_connect(vconn) != EAGAIN) {
738 poll_immediate_wake();
740 switch (sslv->state) {
741 case STATE_TCP_CONNECTING:
742 poll_fd_wait(sslv->fd, POLLOUT);
745 case STATE_SSL_CONNECTING:
746 /* ssl_connect() called SSL_accept() or SSL_connect(), which
747 * set up the status that we test here. */
748 poll_fd_wait(sslv->fd,
749 want_to_poll_events(SSL_want(sslv->ssl)));
759 if (sslv->rx_want != SSL_NOTHING) {
760 poll_fd_wait(sslv->fd, want_to_poll_events(sslv->rx_want));
762 poll_immediate_wake();
768 /* We have room in our tx queue. */
769 poll_immediate_wake();
771 /* The call to ssl_tx_poll_callback() will wake us up. */
780 struct vconn_class ssl_vconn_class = {
783 ssl_close, /* close */
784 ssl_connect, /* connect */
794 struct pvconn pvconn;
798 struct pvconn_class pssl_pvconn_class;
800 static struct pssl_pvconn *
801 pssl_pvconn_cast(struct pvconn *pvconn)
803 pvconn_assert_class(pvconn, &pssl_pvconn_class);
804 return CONTAINER_OF(pvconn, struct pssl_pvconn, pvconn);
808 pssl_open(const char *name, char *suffix, struct pvconn **pvconnp)
810 struct sockaddr_in sin;
811 struct pssl_pvconn *pssl;
814 unsigned int yes = 1;
822 fd = socket(AF_INET, SOCK_STREAM, 0);
825 VLOG_ERR("%s: socket: %s", name, strerror(error));
829 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes) < 0) {
831 VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s", name, strerror(errno));
835 memset(&sin, 0, sizeof sin);
836 sin.sin_family = AF_INET;
837 sin.sin_addr.s_addr = htonl(INADDR_ANY);
838 sin.sin_port = htons(atoi(suffix) ? atoi(suffix) : OFP_SSL_PORT);
839 retval = bind(fd, (struct sockaddr *) &sin, sizeof sin);
842 VLOG_ERR("%s: bind: %s", name, strerror(error));
847 retval = listen(fd, 10);
850 VLOG_ERR("%s: listen: %s", name, strerror(error));
855 retval = set_nonblocking(fd);
861 pssl = xmalloc(sizeof *pssl);
862 pvconn_init(&pssl->pvconn, &pssl_pvconn_class, name);
864 *pvconnp = &pssl->pvconn;
869 pssl_close(struct pvconn *pvconn)
871 struct pssl_pvconn *pssl = pssl_pvconn_cast(pvconn);
877 pssl_accept(struct pvconn *pvconn, struct vconn **new_vconnp)
879 struct pssl_pvconn *pssl = pssl_pvconn_cast(pvconn);
880 struct sockaddr_in sin;
881 socklen_t sin_len = sizeof sin;
886 new_fd = accept(pssl->fd, &sin, &sin_len);
889 if (error != EAGAIN) {
890 VLOG_DBG_RL(&rl, "accept: %s", strerror(error));
895 error = set_nonblocking(new_fd);
901 sprintf(name, "ssl:"IP_FMT, IP_ARGS(&sin.sin_addr));
902 if (sin.sin_port != htons(OFP_SSL_PORT)) {
903 sprintf(strchr(name, '\0'), ":%"PRIu16, ntohs(sin.sin_port));
905 return new_ssl_vconn(name, new_fd, SERVER, STATE_SSL_CONNECTING, &sin,
910 pssl_wait(struct pvconn *pvconn)
912 struct pssl_pvconn *pssl = pssl_pvconn_cast(pvconn);
913 poll_fd_wait(pssl->fd, POLLIN);
916 struct pvconn_class pssl_pvconn_class = {
925 * Returns true if OpenSSL error is WANT_READ or WANT_WRITE, indicating that
926 * OpenSSL is requesting that we call it back when the socket is ready for read
927 * or writing, respectively.
930 ssl_wants_io(int ssl_error)
932 return (ssl_error == SSL_ERROR_WANT_WRITE
933 || ssl_error == SSL_ERROR_WANT_READ);
939 static int init_status = -1;
940 if (init_status < 0) {
941 init_status = do_ssl_init();
942 assert(init_status >= 0);
953 SSL_load_error_strings();
955 method = TLSv1_method();
956 if (method == NULL) {
957 VLOG_ERR("TLSv1_method: %s", ERR_error_string(ERR_get_error(), NULL));
961 ctx = SSL_CTX_new(method);
963 VLOG_ERR("SSL_CTX_new: %s", ERR_error_string(ERR_get_error(), NULL));
966 SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
967 SSL_CTX_set_tmp_dh_callback(ctx, tmp_dh_callback);
968 SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
969 SSL_CTX_set_mode(ctx, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
970 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
977 tmp_dh_callback(SSL *ssl UNUSED, int is_export UNUSED, int keylength)
982 DH *(*constructor)(void);
985 static struct dh dh_table[] = {
986 {1024, NULL, get_dh1024},
987 {2048, NULL, get_dh2048},
988 {4096, NULL, get_dh4096},
993 for (dh = dh_table; dh < &dh_table[ARRAY_SIZE(dh_table)]; dh++) {
994 if (dh->keylength == keylength) {
996 dh->dh = dh->constructor();
998 ovs_fatal(ENOMEM, "out of memory constructing "
999 "Diffie-Hellman parameters");
1005 VLOG_ERR_RL(&rl, "no Diffie-Hellman parameters for key length %d",
1010 /* Returns true if SSL is at least partially configured. */
1012 vconn_ssl_is_configured(void)
1014 return has_private_key || has_certificate || has_ca_cert;
1018 vconn_ssl_set_private_key_file(const char *file_name)
1023 if (SSL_CTX_use_PrivateKey_file(ctx, file_name, SSL_FILETYPE_PEM) != 1) {
1024 VLOG_ERR("SSL_use_PrivateKey_file: %s",
1025 ERR_error_string(ERR_get_error(), NULL));
1028 has_private_key = true;
1032 vconn_ssl_set_certificate_file(const char *file_name)
1037 if (SSL_CTX_use_certificate_chain_file(ctx, file_name) != 1) {
1038 VLOG_ERR("SSL_use_certificate_file: %s",
1039 ERR_error_string(ERR_get_error(), NULL));
1042 has_certificate = true;
1045 /* Reads the X509 certificate or certificates in file 'file_name'. On success,
1046 * stores the address of the first element in an array of pointers to
1047 * certificates in '*certs' and the number of certificates in the array in
1048 * '*n_certs', and returns 0. On failure, stores a null pointer in '*certs', 0
1049 * in '*n_certs', and returns a positive errno value.
1051 * The caller is responsible for freeing '*certs'. */
1053 read_cert_file(const char *file_name, X509 ***certs, size_t *n_certs)
1056 size_t allocated_certs = 0;
1061 file = fopen(file_name, "r");
1063 VLOG_ERR("failed to open %s for reading: %s",
1064 file_name, strerror(errno));
1072 /* Read certificate from file. */
1073 certificate = PEM_read_X509(file, NULL, NULL, NULL);
1077 VLOG_ERR("PEM_read_X509 failed reading %s: %s",
1078 file_name, ERR_error_string(ERR_get_error(), NULL));
1079 for (i = 0; i < *n_certs; i++) {
1080 X509_free((*certs)[i]);
1088 /* Add certificate to array. */
1089 if (*n_certs >= allocated_certs) {
1090 *certs = x2nrealloc(*certs, &allocated_certs, sizeof **certs);
1092 (*certs)[(*n_certs)++] = certificate;
1094 /* Are there additional certificates in the file? */
1097 } while (isspace(c));
1108 /* Sets 'file_name' as the name of a file containing one or more X509
1109 * certificates to send to the peer. Typical use in OpenFlow is to send the CA
1110 * certificate to the peer, which enables a switch to pick up the controller's
1111 * CA certificate on its first connection. */
1113 vconn_ssl_set_peer_ca_cert_file(const char *file_name)
1123 if (!read_cert_file(file_name, &certs, &n_certs)) {
1124 for (i = 0; i < n_certs; i++) {
1125 if (SSL_CTX_add_extra_chain_cert(ctx, certs[i]) != 1) {
1126 VLOG_ERR("SSL_CTX_add_extra_chain_cert: %s",
1127 ERR_error_string(ERR_get_error(), NULL));
1134 /* Logs fingerprint of CA certificate 'cert' obtained from 'file_name'. */
1136 log_ca_cert(const char *file_name, X509 *cert)
1138 unsigned char digest[EVP_MAX_MD_SIZE];
1139 unsigned int n_bytes;
1144 if (!X509_digest(cert, EVP_sha1(), digest, &n_bytes)) {
1145 ds_put_cstr(&fp, "<out of memory>");
1148 for (i = 0; i < n_bytes; i++) {
1150 ds_put_char(&fp, ':');
1152 ds_put_format(&fp, "%02hhx", digest[i]);
1155 subject = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0);
1156 VLOG_INFO("Trusting CA cert from %s (%s) (fingerprint %s)", file_name,
1157 subject ? subject : "<out of memory>", ds_cstr(&fp));
1162 /* Sets 'file_name' as the name of the file from which to read the CA
1163 * certificate used to verify the peer within SSL connections. If 'bootstrap'
1164 * is false, the file must exist. If 'bootstrap' is false, then the file is
1165 * read if it is exists; if it does not, then it will be created from the CA
1166 * certificate received from the peer on the first SSL connection. */
1168 vconn_ssl_set_ca_cert_file(const char *file_name, bool bootstrap)
1178 if (bootstrap && stat(file_name, &s) && errno == ENOENT) {
1179 bootstrap_ca_cert = true;
1180 ca_cert_file = xstrdup(file_name);
1181 } else if (!read_cert_file(file_name, &certs, &n_certs)) {
1184 /* Set up list of CAs that the server will accept from the client. */
1185 for (i = 0; i < n_certs; i++) {
1186 /* SSL_CTX_add_client_CA makes a copy of the relevant data. */
1187 if (SSL_CTX_add_client_CA(ctx, certs[i]) != 1) {
1188 VLOG_ERR("failed to add client certificate %d from %s: %s",
1190 ERR_error_string(ERR_get_error(), NULL));
1192 log_ca_cert(file_name, certs[i]);
1194 X509_free(certs[i]);
1197 /* Set up CAs for OpenSSL to trust in verifying the peer's
1199 if (SSL_CTX_load_verify_locations(ctx, file_name, NULL) != 1) {
1200 VLOG_ERR("SSL_CTX_load_verify_locations: %s",
1201 ERR_error_string(ERR_get_error(), NULL));