#include <sys/fcntl.h>
#include <sys/stat.h>
#include <unistd.h>
+#include "coverage.h"
#include "dynamic-string.h"
#include "leak-checker.h"
#include "ofpbuf.h"
#include "openflow/openflow.h"
#include "packets.h"
#include "poll-loop.h"
+#include "shash.h"
#include "socket-util.h"
#include "util.h"
#include "stream-provider.h"
#include "stream.h"
#include "timeval.h"
-
#include "vlog.h"
-#define THIS_MODULE VLM_stream_ssl
+
+VLOG_DEFINE_THIS_MODULE(stream_ssl)
/* Active SSL. */
{
struct stream stream;
enum ssl_state state;
- int connect_error;
enum session_type type;
int fd;
SSL *ssl;
/* SSL context created by ssl_init(). */
static SSL_CTX *ctx;
+/* Maps from stream target (e.g. "127.0.0.1:1234") to SSL_SESSION *. The
+ * sessions are those from the last SSL connection to the given target.
+ * OpenSSL caches server-side sessions internally, so this cache is only used
+ * for client connections.
+ *
+ * The stream_ssl module owns a reference to each of the sessions in this
+ * table, so they must be freed with SSL_SESSION_free() when they are no
+ * longer needed. */
+static struct shash client_sessions = SHASH_INITIALIZER(&client_sessions);
+
+/* Maximum number of client sessions to cache. Ordinarily I'd expect that one
+ * session would be sufficient but this should cover it. */
+#define MAX_CLIENT_SESSION_CACHE 16
+
struct ssl_config_file {
bool read; /* Whether the file was successfully read. */
char *file_name; /* Configured file name, if any. */
return EPROTO;
}
+static void
+ssl_delete_session(struct shash_node *node)
+{
+ SSL_SESSION *session = node->data;
+ SSL_SESSION_free(session);
+ shash_delete(&client_sessions, node);
+}
+
+/* Find and free any previously cached session for 'stream''s target. */
+static void
+ssl_flush_session(struct stream *stream)
+{
+ struct shash_node *node;
+
+ node = shash_find(&client_sessions, stream_get_name(stream));
+ if (node) {
+ ssl_delete_session(node);
+ }
+}
+
+/* Add 'stream''s session to the cache for its target, so that it will be
+ * reused for future SSL connections to the same target. */
+static void
+ssl_cache_session(struct stream *stream)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+ SSL_SESSION *session;
+
+ /* Statistics. */
+ COVERAGE_INC(ssl_session);
+ if (SSL_session_reused(sslv->ssl)) {
+ COVERAGE_INC(ssl_session_reused);
+ }
+
+ /* Get session from stream. */
+ session = SSL_get1_session(sslv->ssl);
+ if (session) {
+ SSL_SESSION *old_session;
+
+ old_session = shash_replace(&client_sessions, stream_get_name(stream),
+ session);
+ if (old_session) {
+ /* Free the session that we replaced. (We might actually have
+ * session == old_session, but either way we have to free it to
+ * avoid leaking a reference.) */
+ SSL_SESSION_free(old_session);
+ } else if (shash_count(&client_sessions) > MAX_CLIENT_SESSION_CACHE) {
+ for (;;) {
+ struct shash_node *node = shash_random_node(&client_sessions);
+ if (node->data != session) {
+ ssl_delete_session(node);
+ break;
+ }
+ }
+ }
+ } else {
+ /* There is no new session. This doesn't really make sense because
+ * this function is only called upon successful connection and there
+ * should always be a new session in that case. But I don't trust
+ * OpenSSL so I'd rather handle this case anyway. */
+ ssl_flush_session(stream);
+ }
+}
+
static int
ssl_connect(struct stream *stream)
{
MSG_PEEK);
}
+ /* Grab SSL session information from the cache. */
+ if (sslv->type == CLIENT) {
+ SSL_SESSION *session = shash_find_data(&client_sessions,
+ stream_get_name(stream));
+ if (session) {
+ SSL_set_session(sslv->ssl, session);
+ }
+ }
+
retval = (sslv->type == CLIENT
? SSL_connect(sslv->ssl) : SSL_accept(sslv->ssl));
if (retval != 1) {
return EAGAIN;
} else {
int unused;
+
+ if (sslv->type == CLIENT) {
+ /* Delete any cached session for this stream's target.
+ * Otherwise a single error causes recurring errors that
+ * don't resolve until the SSL client or server is
+ * restarted. (It can take dozens of reused connections to
+ * see this behavior, so this is difficult to test.) If we
+ * delete the session on the first error, though, the error
+ * only occurs once and then resolves itself. */
+ ssl_flush_session(stream);
+ }
+
interpret_ssl_error((sslv->type == CLIENT ? "SSL_connect"
: "SSL_accept"), retval, error, &unused);
shutdown(sslv->fd, SHUT_RDWR);
VLOG_ERR("rejecting SSL connection during bootstrap race window");
return EPROTO;
} else {
+ if (sslv->type == CLIENT) {
+ ssl_cache_session(stream);
+ }
return 0;
}
}
/* Returns true if SSL is at least partially configured. */
bool
-stream_ssl_is_configured(void)
+stream_ssl_is_configured(void)
{
return private_key.file_name || certificate.file_name || ca_cert.file_name;
}
return true;
}
+static void
+stream_ssl_set_private_key_file__(const char *file_name)
+{
+ if (SSL_CTX_use_PrivateKey_file(ctx, file_name, SSL_FILETYPE_PEM) == 1) {
+ private_key.read = true;
+ } else {
+ VLOG_ERR("SSL_use_PrivateKey_file: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ }
+}
+
void
stream_ssl_set_private_key_file(const char *file_name)
{
- if (!update_ssl_config(&private_key, file_name)) {
- return;
+ if (update_ssl_config(&private_key, file_name)) {
+ stream_ssl_set_private_key_file__(file_name);
}
- if (SSL_CTX_use_PrivateKey_file(ctx, file_name, SSL_FILETYPE_PEM) != 1) {
- VLOG_ERR("SSL_use_PrivateKey_file: %s",
+}
+
+static void
+stream_ssl_set_certificate_file__(const char *file_name)
+{
+ if (SSL_CTX_use_certificate_chain_file(ctx, file_name) == 1) {
+ certificate.read = true;
+ } else {
+ VLOG_ERR("SSL_use_certificate_file: %s",
ERR_error_string(ERR_get_error(), NULL));
- return;
}
- private_key.read = true;
}
void
stream_ssl_set_certificate_file(const char *file_name)
{
- if (!update_ssl_config(&certificate, file_name)) {
- return;
+ if (update_ssl_config(&certificate, file_name)) {
+ stream_ssl_set_certificate_file__(file_name);
}
- if (SSL_CTX_use_certificate_chain_file(ctx, file_name) != 1) {
- VLOG_ERR("SSL_use_certificate_file: %s",
- ERR_error_string(ERR_get_error(), NULL));
- return;
+}
+
+/* Sets the private key and certificate files in one operation. Use this
+ * interface, instead of calling stream_ssl_set_private_key_file() and
+ * stream_ssl_set_certificate_file() individually, in the main loop of a
+ * long-running program whose key and certificate might change at runtime.
+ *
+ * This is important because of OpenSSL's behavior. If an OpenSSL context
+ * already has a certificate, and stream_ssl_set_private_key_file() is called
+ * to install a new private key, OpenSSL will report an error because the new
+ * private key does not match the old certificate. The other order, of setting
+ * a new certificate, then setting a new private key, does work.
+ *
+ * If this were the only problem, calling stream_ssl_set_certificate_file()
+ * before stream_ssl_set_private_key_file() would fix it. But, if the private
+ * key is changed before the certificate (e.g. someone "scp"s or "mv"s the new
+ * private key in place before the certificate), then OpenSSL would reject that
+ * change, and then the change of certificate would succeed, but there would be
+ * no associated private key (because it had only changed once and therefore
+ * there was no point in re-reading it).
+ *
+ * This function avoids both problems by, whenever either the certificate or
+ * the private key file changes, re-reading both of them, in the correct order.
+ */
+void
+stream_ssl_set_key_and_cert(const char *private_key_file,
+ const char *certificate_file)
+{
+ if (update_ssl_config(&private_key, private_key_file)
+ || update_ssl_config(&certificate, certificate_file)) {
+ stream_ssl_set_certificate_file__(certificate_file);
+ stream_ssl_set_private_key_file__(private_key_file);
}
- certificate.read = true;
}
/* Reads the X509 certificate or certificates in file 'file_name'. On success,
subject = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0);
VLOG_INFO("Trusting CA cert from %s (%s) (fingerprint %s)", file_name,
subject ? subject : "<out of memory>", ds_cstr(&fp));
- free(subject);
+ OPENSSL_free(subject);
ds_destroy(&fp);
}
git://git.onelab.eu / sliver-openvswitch.git / blobdiff