int virNetServerClientInit(virNetServerClientPtr client)
{
virObjectLock(client);
#if WITH_GNUTLS
if (!client->tlsCtxt) {
#endif
/* Plain socket, so prepare to read first message */
if (virNetServerClientRegisterEvent(client) < 0)
goto error;
#if WITH_GNUTLS
} else {
int ret;
if (!(client->tls = virNetTLSSessionNew(client->tlsCtxt,
NULL)))
goto error;
virNetSocketSetTLSSession(client->sock,
client->tls);
/* Begin the TLS handshake. */
ret = virNetTLSSessionHandshake(client->tls);
if (ret == 0) {
/* Unlikely, but ... Next step is to check the certificate. */
if (virNetServerClientCheckAccess(client) < 0)
goto error;
/* Handshake & cert check OK, so prepare to read first message */
if (virNetServerClientRegisterEvent(client) < 0)
goto error;
} else if (ret > 0) {
/* Most likely, need to do more handshake data */
if (virNetServerClientRegisterEvent(client) < 0)
goto error;
} else {
goto error;
}
}
#endif
virObjectUnlock(client);
return 0;
error:
client->wantClose = true;
virObjectUnlock(client);
return -1;
}
static void
virNetServerClientDispatchHandshake(virNetServerClientPtr client)
{
int ret;
/* Continue the handshake. */
ret = virNetTLSSessionHandshake(client->tls);
if (ret == 0) {
/* Finished. Next step is to check the certificate. */
if (virNetServerClientCheckAccess(client) < 0)
client->wantClose = true;
else
virNetServerClientUpdateEvent(client);
} else if (ret > 0) {
/* Carry on waiting for more handshake. Update
the events just in case handshake data flow
direction has changed */
virNetServerClientUpdateEvent (client);
} else {
/* Fatal error in handshake */
client->wantClose = true;
}
}
/*
* This tests validation checking of peer certificates
*
* This is replicating the checks that are done for an
* active TLS session after handshake completes. To
* simulate that we create our TLS contexts, skipping
* sanity checks. When then get a socketpair, and
* initiate a TLS session across them. Finally do
* do actual cert validation tests
*/
static int testTLSSessionInit(const void *opaque)
{
struct testTLSSessionData *data = (struct testTLSSessionData *)opaque;
virNetTLSContextPtr clientCtxt = NULL;
virNetTLSContextPtr serverCtxt = NULL;
virNetTLSSessionPtr clientSess = NULL;
virNetTLSSessionPtr serverSess = NULL;
int ret = -1;
int channel[2];
bool clientShake = false;
bool serverShake = false;
/* We'll use this for our fake client-server connection */
if (socketpair(AF_UNIX, SOCK_STREAM, 0, channel) < 0)
abort();
/*
* We have an evil loop to do the handshake in a single
* thread, so we need these non-blocking to avoid deadlock
* of ourselves
*/
ignore_value(virSetNonBlock(channel[0]));
ignore_value(virSetNonBlock(channel[1]));
/* We skip initial sanity checks here because we
* want to make sure that problems are being
* detected at the TLS session validation stage
*/
serverCtxt = virNetTLSContextNewServer(data->servercacrt,
NULL,
data->servercrt,
KEYFILE,
data->wildcards,
NULL,
false,
true);
clientCtxt = virNetTLSContextNewClient(data->clientcacrt,
NULL,
data->clientcrt,
KEYFILE,
NULL,
false,
true);
if (!serverCtxt) {
VIR_WARN("Unexpected failure loading %s against %s",
data->servercacrt, data->servercrt);
goto cleanup;
}
if (!clientCtxt) {
VIR_WARN("Unexpected failure loading %s against %s",
data->clientcacrt, data->clientcrt);
goto cleanup;
}
/* Now the real part of the test, setup the sessions */
serverSess = virNetTLSSessionNew(serverCtxt, NULL);
clientSess = virNetTLSSessionNew(clientCtxt, data->hostname);
if (!serverSess) {
VIR_WARN("Unexpected failure using %s against %s",
data->servercacrt, data->servercrt);
goto cleanup;
}
if (!clientSess) {
VIR_WARN("Unexpected failure using %s against %s",
data->clientcacrt, data->clientcrt);
goto cleanup;
}
/* For handshake to work, we need to set the I/O callbacks
* to read/write over the socketpair
*/
virNetTLSSessionSetIOCallbacks(serverSess, testWrite, testRead, &channel[0]);
virNetTLSSessionSetIOCallbacks(clientSess, testWrite, testRead, &channel[1]);
/*
* Finally we loop around & around doing handshake on each
* session until we get an error, or the handshake completes.
* This relies on the socketpair being nonblocking to avoid
* deadlocking ourselves upon handshake
*/
do {
int rv;
if (!serverShake) {
rv = virNetTLSSessionHandshake(serverSess);
if (rv < 0)
goto cleanup;
if (rv == VIR_NET_TLS_HANDSHAKE_COMPLETE)
serverShake = true;
}
if (!clientShake) {
rv = virNetTLSSessionHandshake(clientSess);
if (rv < 0)
goto cleanup;
if (rv == VIR_NET_TLS_HANDSHAKE_COMPLETE)
clientShake = true;
}
} while (!clientShake && !serverShake);
/* Finally make sure the server validation does what
* we were expecting
*/
if (virNetTLSContextCheckCertificate(serverCtxt,
serverSess) < 0) {
if (!data->expectServerFail) {
VIR_WARN("Unexpected server cert check fail");
goto cleanup;
} else {
VIR_DEBUG("Got expected server cert fail");
}
} else {
if (data->expectServerFail) {
VIR_WARN("Expected server cert check fail");
goto cleanup;
} else {
VIR_DEBUG("No unexpected server cert fail");
}
}
/*
* And the same for the client validation check
*/
if (virNetTLSContextCheckCertificate(clientCtxt,
clientSess) < 0) {
if (!data->expectClientFail) {
VIR_WARN("Unexpected client cert check fail");
goto cleanup;
} else {
VIR_DEBUG("Got expected client cert fail");
}
} else {
if (data->expectClientFail) {
VIR_WARN("Expected client cert check fail");
goto cleanup;
} else {
VIR_DEBUG("No unexpected client cert fail");
}
}
ret = 0;
cleanup:
virObjectUnref(serverCtxt);
virObjectUnref(clientCtxt);
virObjectUnref(serverSess);
virObjectUnref(clientSess);
VIR_FORCE_CLOSE(channel[0]);
VIR_FORCE_CLOSE(channel[1]);
return ret;
}
int virNetClientSetTLSSession(virNetClientPtr client,
virNetTLSContextPtr tls)
{
int ret;
char buf[1];
int len;
struct pollfd fds[1];
sigset_t oldmask, blockedsigs;
sigemptyset (&blockedsigs);
#ifdef SIGWINCH
sigaddset (&blockedsigs, SIGWINCH);
#endif
#ifdef SIGCHLD
sigaddset (&blockedsigs, SIGCHLD);
#endif
sigaddset (&blockedsigs, SIGPIPE);
virNetClientLock(client);
if (!(client->tls = virNetTLSSessionNew(tls,
client->hostname)))
goto error;
virNetSocketSetTLSSession(client->sock, client->tls);
for (;;) {
ret = virNetTLSSessionHandshake(client->tls);
if (ret < 0)
goto error;
if (ret == 0)
break;
fds[0].fd = virNetSocketGetFD(client->sock);
fds[0].revents = 0;
if (virNetTLSSessionGetHandshakeStatus(client->tls) ==
VIR_NET_TLS_HANDSHAKE_RECVING)
fds[0].events = POLLIN;
else
fds[0].events = POLLOUT;
/* Block SIGWINCH from interrupting poll in curses programs,
* then restore the original signal mask again immediately
* after the call (RHBZ#567931). Same for SIGCHLD and SIGPIPE
* at the suggestion of Paolo Bonzini and Daniel Berrange.
*/
ignore_value(pthread_sigmask(SIG_BLOCK, &blockedsigs, &oldmask));
repoll:
ret = poll(fds, ARRAY_CARDINALITY(fds), -1);
if (ret < 0 && errno == EAGAIN)
goto repoll;
ignore_value(pthread_sigmask(SIG_BLOCK, &oldmask, NULL));
}
ret = virNetTLSContextCheckCertificate(tls, client->tls);
if (ret < 0)
goto error;
/* At this point, the server is verifying _our_ certificate, IP address,
* etc. If we make the grade, it will send us a '\1' byte.
*/
fds[0].fd = virNetSocketGetFD(client->sock);
fds[0].revents = 0;
fds[0].events = POLLIN;
/* Block SIGWINCH from interrupting poll in curses programs */
ignore_value(pthread_sigmask(SIG_BLOCK, &blockedsigs, &oldmask));
repoll2:
ret = poll(fds, ARRAY_CARDINALITY(fds), -1);
if (ret < 0 && errno == EAGAIN)
goto repoll2;
ignore_value(pthread_sigmask(SIG_BLOCK, &oldmask, NULL));
len = virNetTLSSessionRead(client->tls, buf, 1);
if (len < 0 && errno != ENOMSG) {
virReportSystemError(errno, "%s",
_("Unable to read TLS confirmation"));
goto error;
}
if (len != 1 || buf[0] != '\1') {
virNetError(VIR_ERR_RPC, "%s",
_("server verification (of our certificate or IP "
"address) failed"));
goto error;
}
virNetClientUnlock(client);
return 0;
error:
virNetTLSSessionFree(client->tls);
client->tls = NULL;
virNetClientUnlock(client);
return -1;
}