[libvirt] [PATCH v5 4/7] libssh_transport: add new libssh-based transport
Pino Toscano
ptoscano at redhat.com
Wed Nov 9 14:28:35 UTC 2016
Implement a new libssh transport, which uses libssh to communicate with
remote hosts, and add all the build system stuff (search of libssh,
private symbols, etc) to built it.
This new transport supports all the common ssh authentication methods,
making use of libvirt's auth callbacks for interaction with the user.
---
config-post.h | 2 +
configure.ac | 3 +
m4/virt-libssh.m4 | 26 +
po/POTFILES.in | 1 +
src/Makefile.am | 21 +-
src/libvirt_libssh.syms | 21 +
src/rpc/virnetlibsshsession.c | 1492 +++++++++++++++++++++++++++++++++++++++++
src/rpc/virnetlibsshsession.h | 78 +++
8 files changed, 1642 insertions(+), 2 deletions(-)
create mode 100644 m4/virt-libssh.m4
create mode 100644 src/libvirt_libssh.syms
create mode 100644 src/rpc/virnetlibsshsession.c
create mode 100644 src/rpc/virnetlibsshsession.h
diff --git a/config-post.h b/config-post.h
index 6eb63db..090cc28 100644
--- a/config-post.h
+++ b/config-post.h
@@ -36,6 +36,7 @@
# undef WITH_DTRACE_PROBES
# undef WITH_GNUTLS
# undef WITH_GNUTLS_GCRYPT
+# undef WITH_LIBSSH
# undef WITH_MACVTAP
# undef WITH_NUMACTL
# undef WITH_SASL
@@ -60,6 +61,7 @@
# undef WITH_DTRACE_PROBES
# undef WITH_GNUTLS
# undef WITH_GNUTLS_GCRYPT
+# undef WITH_LIBSSH
# undef WITH_MACVTAP
# undef WITH_NUMACTL
# undef WITH_SASL
diff --git a/configure.ac b/configure.ac
index 9e26b8c..807b323 100644
--- a/configure.ac
+++ b/configure.ac
@@ -217,6 +217,7 @@ if test "$with_remote" = "no" ; then
with_gnutls=no
with_ssh2=no
with_sasl=no
+ with_libssh=no
fi
# Stateful drivers are useful only when building the daemon.
if test "$with_libvirtd" = "no" ; then
@@ -246,6 +247,7 @@ LIBVIRT_CHECK_DBUS
LIBVIRT_CHECK_FUSE
LIBVIRT_CHECK_GLUSTER
LIBVIRT_CHECK_HAL
+LIBVIRT_CHECK_LIBSSH
LIBVIRT_CHECK_NETCF
LIBVIRT_CHECK_NUMACTL
LIBVIRT_CHECK_OPENWSMAN
@@ -2685,6 +2687,7 @@ LIBVIRT_RESULT_DBUS
LIBVIRT_RESULT_FUSE
LIBVIRT_RESULT_GLUSTER
LIBVIRT_RESULT_HAL
+LIBVIRT_RESULT_LIBSSH
LIBVIRT_RESULT_NETCF
LIBVIRT_RESULT_NUMACTL
LIBVIRT_RESULT_OPENWSMAN
diff --git a/m4/virt-libssh.m4 b/m4/virt-libssh.m4
new file mode 100644
index 0000000..88ece21
--- /dev/null
+++ b/m4/virt-libssh.m4
@@ -0,0 +1,26 @@
+dnl The libssh.so library
+dnl
+dnl Copyright (C) 2016 Red Hat, Inc.
+dnl
+dnl This library is free software; you can redistribute it and/or
+dnl modify it under the terms of the GNU Lesser General Public
+dnl License as published by the Free Software Foundation; either
+dnl version 2.1 of the License, or (at your option) any later version.
+dnl
+dnl This library is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+dnl Lesser General Public License for more details.
+dnl
+dnl You should have received a copy of the GNU Lesser General Public
+dnl License along with this library. If not, see
+dnl <http://www.gnu.org/licenses/>.
+dnl
+
+AC_DEFUN([LIBVIRT_CHECK_LIBSSH],[
+ LIBVIRT_CHECK_PKG([LIBSSH], [libssh], [0.7])
+])
+
+AC_DEFUN([LIBVIRT_RESULT_LIBSSH],[
+ LIBVIRT_RESULT_LIB([LIBSSH])
+])
diff --git a/po/POTFILES.in b/po/POTFILES.in
index 1469240..c8905f7 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -144,6 +144,7 @@ src/rpc/virnetclient.c
src/rpc/virnetclientprogram.c
src/rpc/virnetclientstream.c
src/rpc/virnetdaemon.c
+src/rpc/virnetlibsshsession.c
src/rpc/virnetmessage.c
src/rpc/virnetsaslcontext.c
src/rpc/virnetserver.c
diff --git a/src/Makefile.am b/src/Makefile.am
index d417b6e..aaba9e6 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -2127,6 +2127,12 @@ else ! WITH_ATOMIC_OPS_PTHREAD
SYM_FILES += $(srcdir)/libvirt_atomic.syms
endif ! WITH_ATOMIC_OPS_PTHREAD
+if WITH_LIBSSH
+USED_SYM_FILES += $(srcdir)/libvirt_libssh.syms
+else ! WITH_LIBSSH
+SYM_FILES += $(srcdir)/libvirt_libssh.syms
+endif ! WITH_LIBSSH
+
EXTRA_DIST += \
libvirt_public.syms \
libvirt_lxc.syms \
@@ -2204,7 +2210,8 @@ libvirt_admin_la_CFLAGS += \
$(YAJL_CFLAGS) \
$(SSH2_CFLAGS) \
$(SASL_CFLAGS) \
- $(GNUTLS_CFLAGS)
+ $(GNUTLS_CFLAGS) \
+ $(LIBSSH_CFLAGS)
libvirt_admin_la_LIBADD += \
$(CAPNG_LIBS) \
@@ -2213,7 +2220,8 @@ libvirt_admin_la_LIBADD += \
$(LIBXML_LIBS) \
$(SSH2_LIBS) \
$(SASL_LIBS) \
- $(GNUTLS_LIBS)
+ $(GNUTLS_LIBS) \
+ $(LIBSSH_LIBS)
ADMIN_SYM_FILES = $(srcdir)/libvirt_admin_private.syms
@@ -2790,16 +2798,25 @@ else ! WITH_SASL
EXTRA_DIST += \
rpc/virnetsaslcontext.h rpc/virnetsaslcontext.c
endif ! WITH_SASL
+if WITH_LIBSSH
+libvirt_net_rpc_la_SOURCES += \
+ rpc/virnetlibsshsession.h rpc/virnetlibsshsession.c
+else ! WITH_LIBSSH
+EXTRA_DIST += \
+ rpc/virnetlibsshsession.h rpc/virnetlibsshsession.c
+endif ! WITH_LIBSSH
libvirt_net_rpc_la_CFLAGS = \
$(GNUTLS_CFLAGS) \
$(SASL_CFLAGS) \
$(SSH2_CFLAGS) \
+ $(LIBSSH_CFLAGS) \
$(XDR_CFLAGS) \
$(AM_CFLAGS)
libvirt_net_rpc_la_LDFLAGS = \
$(GNUTLS_LIBS) \
$(SASL_LIBS) \
$(SSH2_LIBS)\
+ $(LIBSSH_LIBS) \
$(SECDRIVER_LIBS) \
$(AM_LDFLAGS) \
$(NULL)
diff --git a/src/libvirt_libssh.syms b/src/libvirt_libssh.syms
new file mode 100644
index 0000000..32eb44f
--- /dev/null
+++ b/src/libvirt_libssh.syms
@@ -0,0 +1,21 @@
+#
+# libssh session - specific symbols
+#
+
+# rpc/virnetlibsshsession.h
+virNetLibsshChannelRead;
+virNetLibsshChannelWrite;
+virNetLibsshSessionAuthAddAgentAuth;
+virNetLibsshSessionAuthAddKeyboardAuth;
+virNetLibsshSessionAuthAddPasswordAuth;
+virNetLibsshSessionAuthAddPrivKeyAuth;
+virNetLibsshSessionAuthSetCallback;
+virNetLibsshSessionConnect;
+virNetLibsshSessionHasCachedData;
+virNetLibsshSessionSetChannelCommand;
+virNetLibsshSessionSetHostKeyVerification;
+
+# Let emacs know we want case-insensitive sorting
+# Local Variables:
+# sort-fold-case: t
+# End:
diff --git a/src/rpc/virnetlibsshsession.c b/src/rpc/virnetlibsshsession.c
new file mode 100644
index 0000000..5de6629
--- /dev/null
+++ b/src/rpc/virnetlibsshsession.c
@@ -0,0 +1,1492 @@
+/*
+ * virnetlibsshsession.c: ssh network transport provider based on libssh
+ *
+ * Copyright (C) 2012-2016 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Author: Peter Krempa <pkrempa at redhat.com>
+ * Author: Pino Toscano <ptoscano at redhat.com>
+ */
+#include <config.h>
+#include <libssh/libssh.h>
+
+#include "virnetlibsshsession.h"
+
+#include "internal.h"
+#include "viralloc.h"
+#include "virlog.h"
+#include "configmake.h"
+#include "virutil.h"
+#include "virerror.h"
+#include "virobject.h"
+#include "virstring.h"
+#include "virauth.h"
+#include "virbuffer.h"
+
+#define VIR_FROM_THIS VIR_FROM_LIBSSH
+
+VIR_LOG_INIT("rpc.netlibsshsession");
+
+#define VIR_NET_LIBSSH_BUFFER_SIZE 1024
+
+/* TRACE_LIBSSH=<level> enables tracing in libssh itself.
+ * The meaning of <level> is described here:
+ * http://api.libssh.org/master/group__libssh__log.html
+ *
+ * The LIBVIRT_LIBSSH_DEBUG environment variable can be used
+ * to set/override the level of libssh debug.
+ */
+#define TRACE_LIBSSH 0
+
+typedef enum {
+ VIR_NET_LIBSSH_STATE_NEW,
+ VIR_NET_LIBSSH_STATE_HANDSHAKE_COMPLETE,
+ VIR_NET_LIBSSH_STATE_CLOSED,
+ VIR_NET_LIBSSH_STATE_ERROR,
+ VIR_NET_LIBSSH_STATE_ERROR_REMOTE,
+} virNetLibsshSessionState;
+
+typedef enum {
+ VIR_NET_LIBSSH_AUTH_KEYBOARD_INTERACTIVE,
+ VIR_NET_LIBSSH_AUTH_PASSWORD,
+ VIR_NET_LIBSSH_AUTH_PRIVKEY,
+ VIR_NET_LIBSSH_AUTH_AGENT
+} virNetLibsshAuthMethods;
+
+
+typedef struct _virNetLibsshAuthMethod virNetLibsshAuthMethod;
+typedef virNetLibsshAuthMethod *virNetLibsshAuthMethodPtr;
+
+struct _virNetLibsshAuthMethod {
+ virNetLibsshAuthMethods method;
+ int ssh_flags; /* SSH_AUTH_METHOD_* for this auth method */
+
+ char *password;
+ char *filename;
+
+ int tries;
+};
+
+struct _virNetLibsshSession {
+ virObjectLockable parent;
+ virNetLibsshSessionState state;
+
+ /* libssh internal stuff */
+ ssh_session session;
+ ssh_channel channel;
+
+ /* for host key checking */
+ virNetLibsshHostkeyVerify hostKeyVerify;
+ char *knownHostsFile;
+ char *hostname;
+ int port;
+
+ /* authentication stuff */
+ char *username;
+ virConnectAuthPtr cred;
+ char *authPath;
+ size_t nauths;
+ virNetLibsshAuthMethodPtr *auths;
+
+ /* channel stuff */
+ char *channelCommand;
+ int channelCommandReturnValue;
+
+ /* read cache */
+ char rbuf[VIR_NET_LIBSSH_BUFFER_SIZE];
+ size_t bufUsed;
+ size_t bufStart;
+};
+
+static void
+virNetLibsshSessionAuthMethodsFree(virNetLibsshSessionPtr sess)
+{
+ size_t i;
+
+ for (i = 0; i < sess->nauths; i++) {
+ VIR_DISPOSE_STRING(sess->auths[i]->password);
+ VIR_FREE(sess->auths[i]->filename);
+ VIR_FREE(sess->auths[i]);
+ }
+
+ VIR_FREE(sess->auths);
+ sess->nauths = 0;
+}
+
+static void
+virNetLibsshSessionDispose(void *obj)
+{
+ virNetLibsshSessionPtr sess = obj;
+ VIR_DEBUG("sess=0x%p", sess);
+
+ if (!sess)
+ return;
+
+ if (sess->channel) {
+ ssh_channel_send_eof(sess->channel);
+ ssh_channel_close(sess->channel);
+ ssh_channel_free(sess->channel);
+ }
+
+ if (sess->session) {
+ ssh_disconnect(sess->session);
+ ssh_free(sess->session);
+ }
+
+ virNetLibsshSessionAuthMethodsFree(sess);
+
+ VIR_FREE(sess->channelCommand);
+ VIR_FREE(sess->hostname);
+ VIR_FREE(sess->knownHostsFile);
+ VIR_FREE(sess->authPath);
+ VIR_FREE(sess->username);
+}
+
+static virClassPtr virNetLibsshSessionClass;
+static int
+virNetLibsshSessionOnceInit(void)
+{
+ const char *dbgLevelStr;
+
+ if (!(virNetLibsshSessionClass = virClassNew(virClassForObjectLockable(),
+ "virNetLibsshSession",
+ sizeof(virNetLibsshSession),
+ virNetLibsshSessionDispose)))
+ return -1;
+
+ if (ssh_init() < 0) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("failed to initialize libssh"));
+ return -1;
+ }
+
+#if TRACE_LIBSSH != 0
+ ssh_set_log_level(TRACE_LIBSSH);
+#endif
+
+ dbgLevelStr = virGetEnvAllowSUID("LIBVIRT_LIBSSH_DEBUG");
+ if (dbgLevelStr) {
+ int dbgLevel = virParseNumber(&dbgLevelStr);
+ ssh_set_log_level(dbgLevel);
+ }
+
+ return 0;
+}
+VIR_ONCE_GLOBAL_INIT(virNetLibsshSession);
+
+static virNetLibsshAuthMethodPtr
+virNetLibsshSessionAuthMethodNew(virNetLibsshSessionPtr sess)
+{
+ virNetLibsshAuthMethodPtr auth;
+
+ if (VIR_ALLOC(auth) < 0)
+ goto error;
+
+ if (VIR_EXPAND_N(sess->auths, sess->nauths, 1) < 0)
+ goto error;
+
+ sess->auths[sess->nauths - 1] = auth;
+
+ return auth;
+
+ error:
+ VIR_FREE(auth);
+ return NULL;
+}
+
+/* string representation of public key of remote server */
+static char *
+virLibsshServerKeyAsString(virNetLibsshSessionPtr sess)
+{
+ int ret;
+ ssh_key key;
+ unsigned char *keyhash;
+ size_t keyhashlen;
+ char *str;
+
+ if (ssh_get_publickey(sess->session, &key) != SSH_OK) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("failed to get the key of the current "
+ "session"));
+ return NULL;
+ }
+
+ /* calculate remote key hash, using SHA1 algorithm that is
+ * usual in OpenSSH. The returned value must be freed */
+ ret = ssh_get_publickey_hash(key, SSH_PUBLICKEY_HASH_SHA1,
+ &keyhash, &keyhashlen);
+ ssh_key_free(key);
+ if (ret < 0) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("failed to calculate ssh host key hash"));
+ return NULL;
+ }
+ /* format the host key into a nice userfriendly string. */
+ str = ssh_get_hexa(keyhash, keyhashlen);
+ ssh_clean_pubkey_hash(&keyhash);
+
+ return str;
+}
+
+static int
+virCredTypeForPrompt(virConnectAuthPtr cred, char echo)
+{
+ size_t i;
+
+ for (i = 0; i < cred->ncredtype; ++i) {
+ int type = cred->credtype[i];
+ if (echo) {
+ if (type == VIR_CRED_ECHOPROMPT)
+ return type;
+ } else {
+ if (type == VIR_CRED_PASSPHRASE ||
+ type == VIR_CRED_NOECHOPROMPT) {
+ return type;
+ }
+ }
+ }
+
+ return -1;
+}
+
+static int
+virLengthForPromptString(const char *str)
+{
+ int len = strlen(str);
+
+ while (len > 0 && (str[len-1] == ' ' || str[len-1] == ':'))
+ --len;
+
+ return len;
+}
+
+/* check session host keys
+ *
+ * this function checks the known host database and verifies the key
+ * errors are raised in this func
+ *
+ * return value: 0 on success, -1 on error
+ */
+static int
+virNetLibsshCheckHostKey(virNetLibsshSessionPtr sess)
+{
+ int state;
+ char *keyhashstr;
+ const char *errmsg;
+
+ if (sess->hostKeyVerify == VIR_NET_LIBSSH_HOSTKEY_VERIFY_IGNORE)
+ return 0;
+
+ state = ssh_is_server_known(sess->session);
+
+ switch (state) {
+ case SSH_SERVER_KNOWN_OK:
+ /* host key matches */
+ return 0;
+
+ case SSH_SERVER_FOUND_OTHER:
+ case SSH_SERVER_KNOWN_CHANGED:
+ keyhashstr = virLibsshServerKeyAsString(sess);
+ if (!keyhashstr)
+ return -1;
+
+ /* host key verification failed */
+ virReportError(VIR_ERR_AUTH_FAILED,
+ _("!!! SSH HOST KEY VERIFICATION FAILED !!!: "
+ "Identity of host '%s:%d' differs from stored identity. "
+ "Please verify the new host key '%s' to avoid possible "
+ "man in the middle attack. The key is stored in '%s'."),
+ sess->hostname, sess->port,
+ keyhashstr, sess->knownHostsFile);
+
+ ssh_string_free_char(keyhashstr);
+ return -1;
+
+ case SSH_SERVER_FILE_NOT_FOUND:
+ case SSH_SERVER_NOT_KNOWN:
+ /* key was not found, query to add it to database */
+ if (sess->hostKeyVerify == VIR_NET_LIBSSH_HOSTKEY_VERIFY_NORMAL) {
+ virConnectCredential askKey;
+ int cred_type;
+ char *tmp;
+
+ /* ask to add the key */
+ if (!sess->cred || !sess->cred->cb) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("No user interaction callback provided: "
+ "Can't verify the session host key"));
+ return -1;
+ }
+
+ cred_type = virCredTypeForPrompt(sess->cred, 1 /* echo */);
+ if (cred_type == -1) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("no suitable callback for host key "
+ "verification"));
+ return -1;
+ }
+
+ /* prepare data for the callback */
+ memset(&askKey, 0, sizeof(virConnectCredential));
+ askKey.type = cred_type;
+
+ keyhashstr = virLibsshServerKeyAsString(sess);
+ if (!keyhashstr)
+ return -1;
+
+ if (virAsprintf(&tmp,
+ _("Accept SSH host key with hash '%s' for "
+ "host '%s:%d' (%s/%s)?"),
+ keyhashstr,
+ sess->hostname, sess->port,
+ "y", "n") < 0) {
+ ssh_string_free_char(keyhashstr);
+ return -1;
+ }
+ askKey.prompt = tmp;
+
+ if (sess->cred->cb(&askKey, 1, sess->cred->cbdata)) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("failed to retrieve decision to accept "
+ "host key"));
+ VIR_FREE(tmp);
+ ssh_string_free_char(keyhashstr);
+ return -1;
+ }
+
+ VIR_FREE(tmp);
+
+ if (!askKey.result ||
+ STRCASENEQ(askKey.result, "y")) {
+ virReportError(VIR_ERR_LIBSSH,
+ _("SSH host key for '%s' (%s) was not accepted"),
+ sess->hostname, keyhashstr);
+ ssh_string_free_char(keyhashstr);
+ VIR_FREE(askKey.result);
+ return -1;
+ }
+ ssh_string_free_char(keyhashstr);
+ VIR_FREE(askKey.result);
+ }
+
+ /* write the host key file */
+ if (ssh_write_knownhost(sess->session) < 0) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("failed to write known_host file '%s': %s"),
+ sess->knownHostsFile,
+ errmsg);
+ return -1;
+ }
+ /* key was accepted and added */
+ return 0;
+
+ case SSH_SERVER_ERROR:
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("failed to validate SSH host key: %s"),
+ errmsg);
+ return -1;
+
+ default: /* should never happen (tm) */
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("Unknown state of the remote server SSH key"));
+ return -1;
+ }
+
+ return -1;
+}
+
+/* callback for ssh_pki_import_privkey_file, used to get the passphrase
+ * of a private key
+ */
+static int
+virNetLibsshAuthenticatePrivkeyCb(const char *prompt,
+ char *buf,
+ size_t len,
+ int echo,
+ int verify ATTRIBUTE_UNUSED,
+ void *userdata)
+{
+ virNetLibsshSessionPtr sess = userdata;
+ virConnectCredential retr_passphrase;
+ int cred_type;
+ char *actual_prompt = NULL;
+ char *p;
+
+ /* request user's key password */
+ if (!sess->cred || !sess->cred->cb) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("No user interaction callback provided: "
+ "Can't retrieve private key passphrase"));
+ return -1;
+ }
+
+ cred_type = virCredTypeForPrompt(sess->cred, echo);
+ if (cred_type == -1) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("no suitable callback for input of key passphrase"));
+ goto error;
+ }
+
+ if (VIR_STRNDUP(actual_prompt, prompt,
+ virLengthForPromptString(prompt)) < 0)
+ goto error;
+
+ memset(&retr_passphrase, 0, sizeof(virConnectCredential));
+ retr_passphrase.type = cred_type;
+ retr_passphrase.prompt = actual_prompt;
+
+ if (sess->cred->cb(&retr_passphrase, 1, sess->cred->cbdata)) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("failed to retrieve private key passphrase: "
+ "callback has failed"));
+ goto error;
+ }
+
+ p = virStrncpy(buf, retr_passphrase.result,
+ retr_passphrase.resultlen, len);
+ VIR_DISPOSE_STRING(retr_passphrase.result);
+ if (!p) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("passphrase is too long for the buffer"));
+ goto error;
+ }
+
+ VIR_FREE(actual_prompt);
+
+ return 0;
+
+ error:
+ VIR_FREE(actual_prompt);
+ return -1;
+}
+
+static int
+virNetLibsshImportPrivkey(virNetLibsshSessionPtr sess,
+ virNetLibsshAuthMethodPtr priv,
+ ssh_key *ret_key)
+{
+ int err;
+ int ret;
+ ssh_key key;
+
+ /* try open the key with the password set, first; since it can
+ * fail with SSH_ERROR also without the callback being called,
+ * reset the error so it is possible to check whether the callback
+ * failed or libssh did.
+ */
+ virResetLastError();
+ ret = ssh_pki_import_privkey_file(priv->filename, priv->password,
+ virNetLibsshAuthenticatePrivkeyCb,
+ sess, &key);
+ if (ret == SSH_EOF) {
+ virReportError(VIR_ERR_AUTH_FAILED,
+ _("error while reading private key '%s'"),
+ priv->filename);
+ err = SSH_AUTH_ERROR;
+ goto error;
+ } else if (ret == SSH_ERROR) {
+ virErrorPtr vir_err = virGetLastError();
+
+ if (!vir_err || !vir_err->code) {
+ virReportError(VIR_ERR_AUTH_FAILED,
+ _("error while opening private key '%s', wrong "
+ "passphrase?"),
+ priv->filename);
+ }
+ err = SSH_AUTH_ERROR;
+ goto error;
+ }
+
+ *ret_key = key;
+ return SSH_AUTH_SUCCESS;
+
+ error:
+ return err;
+}
+
+
+/* perform private key authentication
+ *
+ * returns SSH_AUTH_* values
+ */
+static int
+virNetLibsshAuthenticatePrivkey(virNetLibsshSessionPtr sess,
+ virNetLibsshAuthMethodPtr priv)
+{
+ int err;
+ int ret;
+ char *tmp = NULL;
+ ssh_key public_key = NULL;
+ ssh_key private_key = NULL;
+
+ VIR_DEBUG("sess=%p", sess);
+
+ if (virAsprintf(&tmp, "%s.pub", priv->filename) < 0) {
+ err = SSH_AUTH_ERROR;
+ goto error;
+ }
+
+ /* try to open the public part of the private key */
+ ret = ssh_pki_import_pubkey_file(tmp, &public_key);
+ if (ret == SSH_ERROR) {
+ virReportError(VIR_ERR_AUTH_FAILED,
+ _("error while reading public key '%s'"),
+ tmp);
+ err = SSH_AUTH_ERROR;
+ goto error;
+ } else if (ret == SSH_EOF) {
+ /* load the private key */
+ err = virNetLibsshImportPrivkey(sess, priv, &private_key);
+ if (err != SSH_AUTH_SUCCESS)
+ goto error;
+
+ /* create the public key from the private key */
+ ret = ssh_pki_export_privkey_to_pubkey(private_key, &public_key);
+ if (ret == SSH_ERROR) {
+ virReportError(VIR_ERR_AUTH_FAILED,
+ _("cannot export the public key from the "
+ "private key '%s'"),
+ priv->filename);
+ err = SSH_AUTH_ERROR;
+ goto error;
+ }
+ }
+
+ VIR_FREE(tmp);
+
+ ret = ssh_userauth_try_publickey(sess->session, NULL, public_key);
+ if (ret != SSH_AUTH_SUCCESS) {
+ err = SSH_AUTH_DENIED;
+ goto error;
+ }
+
+ /* load the private key, if it was not loaded yet */
+ if (private_key == NULL) {
+ err = virNetLibsshImportPrivkey(sess, priv, &private_key);
+ if (err != SSH_AUTH_SUCCESS)
+ goto error;
+ }
+
+ ret = ssh_userauth_publickey(sess->session, NULL, private_key);
+ if (ret != SSH_AUTH_SUCCESS) {
+ err = SSH_AUTH_DENIED;
+ goto error;
+ }
+
+ ssh_key_free(private_key);
+ ssh_key_free(public_key);
+
+ return SSH_AUTH_SUCCESS;
+
+ error:
+ if (private_key)
+ ssh_key_free(private_key);
+ if (public_key)
+ ssh_key_free(public_key);
+ VIR_FREE(tmp);
+ return err;
+}
+
+
+/* perform password authentication, either directly or request the password
+ *
+ * returns SSH_AUTH_* values
+ */
+static int
+virNetLibsshAuthenticatePassword(virNetLibsshSessionPtr sess,
+ virNetLibsshAuthMethodPtr priv)
+{
+ char *password = NULL;
+ const char *errmsg;
+ int ret = -1;
+
+ VIR_DEBUG("sess=%p", sess);
+
+ if (priv->password) {
+ /* tunelled password authentication */
+ if ((ret = ssh_userauth_password(sess->session, NULL,
+ priv->password)) == 0) {
+ ret = SSH_AUTH_SUCCESS;
+ goto cleanup;
+ }
+ } else {
+ /* password authentication with interactive password request */
+ if (!sess->cred || !sess->cred->cb) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("Can't perform authentication: "
+ "Authentication callback not provided"));
+ ret = SSH_AUTH_ERROR;
+ goto cleanup;
+ }
+
+ /* Try the authenticating the set amount of times. The server breaks the
+ * connection if maximum number of bad auth tries is exceeded */
+ while (true) {
+ if (!(password = virAuthGetPasswordPath(sess->authPath, sess->cred,
+ "ssh", sess->username,
+ sess->hostname))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("failed to retrieve password"));
+ ret = SSH_AUTH_ERROR;
+ goto cleanup;
+ }
+
+ /* tunelled password authentication */
+ if ((ret = ssh_userauth_password(sess->session, NULL,
+ password)) == 0) {
+ ret = SSH_AUTH_SUCCESS;
+ goto cleanup;
+ }
+
+ VIR_DISPOSE_STRING(password);
+
+ if (ret != SSH_AUTH_DENIED)
+ break;
+ }
+ }
+
+ /* error path */
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_AUTH_FAILED,
+ _("authentication failed: %s"), errmsg);
+
+ return ret;
+
+ cleanup:
+ VIR_DISPOSE_STRING(password);
+ return ret;
+}
+
+/* perform keyboard interactive authentication
+ *
+ * returns SSH_AUTH_* values
+ */
+static int
+virNetLibsshAuthenticateKeyboardInteractive(virNetLibsshSessionPtr sess,
+ virNetLibsshAuthMethodPtr priv)
+{
+ int ret;
+ const char *errmsg;
+ int try = 0;
+
+ /* request user's key password */
+ if (!sess->cred || !sess->cred->cb) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("No user interaction callback provided: "
+ "Can't get input from keyboard interactive "
+ "authentication"));
+ return SSH_AUTH_ERROR;
+ }
+
+ again:
+ ret = ssh_userauth_kbdint(sess->session, NULL, NULL);
+ while (ret == SSH_AUTH_INFO) {
+ const char *name, *instruction;
+ int nprompts, iprompt;
+ virBuffer buff = VIR_BUFFER_INITIALIZER;
+
+ name = ssh_userauth_kbdint_getname(sess->session);
+ instruction = ssh_userauth_kbdint_getinstruction(sess->session);
+ nprompts = ssh_userauth_kbdint_getnprompts(sess->session);
+
+ /* compose the main buffer with name and instruction, if present */
+ if (name && name[0])
+ virBufferAddStr(&buff, name);
+ if (instruction && instruction[0]) {
+ if (virBufferUse(&buff) > 0)
+ virBufferAddChar(&buff, '\n');
+ virBufferAddStr(&buff, instruction);
+ }
+ if (virBufferUse(&buff) > 0)
+ virBufferAddChar(&buff, '\n');
+
+ if (virBufferCheckError(&buff) < 0)
+ return -1;
+
+ for (iprompt = 0; iprompt < nprompts; ++iprompt) {
+ virConnectCredential retr_passphrase;
+ const char *promptStr;
+ int promptStrLen;
+ char echo;
+ char *prompt = NULL;
+ int cred_type;
+
+ /* get the prompt */
+ promptStr = ssh_userauth_kbdint_getprompt(sess->session, iprompt,
+ &echo);
+ promptStrLen = virLengthForPromptString(promptStr);
+
+ cred_type = virCredTypeForPrompt(sess->cred, echo);
+ if (cred_type == -1) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("no suitable callback for input of keyboard "
+ "response"));
+ goto prompt_error;
+ }
+
+ /* create the prompt for the user, using the instruction
+ * buffer if specified
+ */
+ if (virBufferUse(&buff) > 0) {
+ virBuffer prompt_buff = VIR_BUFFER_INITIALIZER;
+
+ virBufferAddBuffer(&prompt_buff, &buff);
+ virBufferAdd(&prompt_buff, promptStr, promptStrLen);
+
+ if (virBufferCheckError(&prompt_buff) < 0)
+ goto prompt_error;
+
+ prompt = virBufferContentAndReset(&prompt_buff);
+ } else {
+ if (VIR_STRNDUP(prompt, promptStr, promptStrLen) < 0)
+ goto prompt_error;
+ }
+
+ memset(&retr_passphrase, 0, sizeof(virConnectCredential));
+ retr_passphrase.type = cred_type;
+ retr_passphrase.prompt = prompt;
+
+ if (retr_passphrase.type == -1) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("no suitable callback for input of key "
+ "passphrase"));
+ goto prompt_error;
+ }
+
+ if (sess->cred->cb(&retr_passphrase, 1, sess->cred->cbdata)) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("failed to retrieve keyboard interactive "
+ "result: callback has failed"));
+ goto prompt_error;
+ }
+
+ VIR_FREE(prompt);
+
+ ret = ssh_userauth_kbdint_setanswer(sess->session, iprompt,
+ retr_passphrase.result);
+ VIR_DISPOSE_STRING(retr_passphrase.result);
+ if (ret < 0) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_AUTH_FAILED,
+ _("authentication failed: %s"), errmsg);
+ goto prompt_error;
+ }
+
+ continue;
+
+ prompt_error:
+ VIR_FREE(prompt);
+ virBufferFreeAndReset(&buff);
+ return SSH_AUTH_ERROR;
+ }
+
+ virBufferFreeAndReset(&buff);
+
+ ret = ssh_userauth_kbdint(sess->session, NULL, NULL);
+ ++try;
+ if (ret == SSH_AUTH_DENIED && (priv->tries < 0 || try < priv->tries))
+ goto again;
+ }
+
+ if (ret == SSH_AUTH_ERROR) {
+ /* error path */
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_AUTH_FAILED,
+ _("authentication failed: %s"), errmsg);
+ }
+
+ return ret;
+}
+
+/* select auth method and authenticate */
+static int
+virNetLibsshAuthenticate(virNetLibsshSessionPtr sess)
+{
+ virNetLibsshAuthMethodPtr auth;
+ bool no_method = false;
+ bool auth_failed = false;
+ const char *errmsg;
+ int ret;
+ int methods;
+ size_t i;
+
+ VIR_DEBUG("sess=%p", sess);
+
+ /* At this point, we can assume there is at least one
+ * authentication method set -- virNetLibsshValidateConfig
+ * already checked that.
+ */
+
+ /* try to authenticate */
+ ret = ssh_userauth_none(sess->session, NULL);
+ if (ret == SSH_AUTH_ERROR) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("Failed to authenticate as 'none': %s"),
+ errmsg);
+ return -1;
+ }
+
+ /* obtain list of supported auth methods */
+ methods = ssh_userauth_list(sess->session, NULL);
+
+ for (i = 0; i < sess->nauths; i++) {
+ auth = sess->auths[i];
+
+ if ((methods & auth->ssh_flags) == 0) {
+ no_method = true;
+ continue;
+ }
+
+ ret = SSH_AUTH_DENIED;
+
+ switch (auth->method) {
+ case VIR_NET_LIBSSH_AUTH_KEYBOARD_INTERACTIVE:
+ /* try to authenticate using the keyboard interactive way */
+ ret = virNetLibsshAuthenticateKeyboardInteractive(sess, auth);
+ break;
+ case VIR_NET_LIBSSH_AUTH_AGENT:
+ /* try to authenticate using ssh-agent */
+ ret = ssh_userauth_agent(sess->session, NULL);
+ if (ret == SSH_AUTH_ERROR) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("failed to authenticate using agent: %s"),
+ errmsg);
+ }
+ break;
+ case VIR_NET_LIBSSH_AUTH_PRIVKEY:
+ /* try to authenticate using the provided ssh key */
+ ret = virNetLibsshAuthenticatePrivkey(sess, auth);
+ break;
+ case VIR_NET_LIBSSH_AUTH_PASSWORD:
+ /* try to authenticate with password */
+ ret = virNetLibsshAuthenticatePassword(sess, auth);
+ break;
+ }
+
+ if (ret == SSH_AUTH_ERROR) {
+ /* virReportError is called already */
+ return -1;
+ } else if (ret == SSH_AUTH_SUCCESS) {
+ /* authenticated */
+ return 0;
+ }
+
+ auth_failed = true;
+ }
+
+ if (sess->nauths == 1) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("failed to authenticate: %s"),
+ errmsg);
+ } else if (no_method && !auth_failed) {
+ virReportError(VIR_ERR_AUTH_FAILED, "%s",
+ _("None of the requested authentication methods "
+ "are supported by the server"));
+ } else {
+ virReportError(VIR_ERR_AUTH_FAILED, "%s",
+ _("All provided authentication methods with credentials "
+ "were rejected by the server"));
+ }
+
+ return -1;
+}
+
+/* open channel */
+static int
+virNetLibsshOpenChannel(virNetLibsshSessionPtr sess)
+{
+ const char *errmsg;
+
+ sess->channel = ssh_channel_new(sess->session);
+ if (!sess->channel) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("failed to create libssh channel: %s"),
+ errmsg);
+ return -1;
+ }
+
+ if (ssh_channel_open_session(sess->channel) != SSH_OK) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("failed to open ssh channel: %s"),
+ errmsg);
+ return -1;
+ }
+
+ if (ssh_channel_request_exec(sess->channel, sess->channelCommand) != SSH_OK) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("failed to execute command '%s': %s"),
+ sess->channelCommand,
+ errmsg);
+ return -1;
+ }
+
+ /* nonblocking mode */
+ ssh_channel_set_blocking(sess->channel, 0);
+
+ /* channel open */
+ return 0;
+}
+
+/* validate if all required parameters are configured */
+static int
+virNetLibsshValidateConfig(virNetLibsshSessionPtr sess)
+{
+ size_t i;
+ bool has_auths = false;
+
+ for (i = 0; i < sess->nauths; ++i) {
+ if (sess->auths[i]) {
+ has_auths = true;
+ break;
+ }
+ }
+ if (!has_auths) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("No authentication methods and credentials "
+ "provided"));
+ return -1;
+ }
+
+ if (!sess->channelCommand) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("No channel command provided"));
+ return -1;
+ }
+
+ if (sess->hostKeyVerify != VIR_NET_LIBSSH_HOSTKEY_VERIFY_IGNORE) {
+ if (!sess->hostname) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("Hostname is needed for host key verification"));
+ return -1;
+ }
+ }
+
+ /* everything ok */
+ return 0;
+}
+
+/* ### PUBLIC API ### */
+int
+virNetLibsshSessionAuthSetCallback(virNetLibsshSessionPtr sess,
+ virConnectAuthPtr auth)
+{
+ virObjectLock(sess);
+ sess->cred = auth;
+ virObjectUnlock(sess);
+ return 0;
+}
+
+int
+virNetLibsshSessionAuthAddPasswordAuth(virNetLibsshSessionPtr sess,
+ virURIPtr uri)
+{
+ int ret;
+ virNetLibsshAuthMethodPtr auth;
+
+ if (uri) {
+ VIR_FREE(sess->authPath);
+
+ if (virAuthGetConfigFilePathURI(uri, &sess->authPath) < 0) {
+ ret = -1;
+ goto cleanup;
+ }
+ }
+
+ virObjectLock(sess);
+
+ if (!(auth = virNetLibsshSessionAuthMethodNew(sess))) {
+ ret = -1;
+ goto cleanup;
+ }
+
+ auth->method = VIR_NET_LIBSSH_AUTH_PASSWORD;
+ auth->ssh_flags = SSH_AUTH_METHOD_PASSWORD;
+
+ ret = 0;
+
+ cleanup:
+ virObjectUnlock(sess);
+ return ret;
+}
+
+int
+virNetLibsshSessionAuthAddAgentAuth(virNetLibsshSessionPtr sess)
+{
+ int ret;
+ virNetLibsshAuthMethodPtr auth;
+
+ virObjectLock(sess);
+
+ if (!(auth = virNetLibsshSessionAuthMethodNew(sess))) {
+ ret = -1;
+ goto cleanup;
+ }
+
+ auth->method = VIR_NET_LIBSSH_AUTH_AGENT;
+ auth->ssh_flags = SSH_AUTH_METHOD_PUBLICKEY;
+
+ ret = 0;
+
+ cleanup:
+ virObjectUnlock(sess);
+ return ret;
+}
+
+int
+virNetLibsshSessionAuthAddPrivKeyAuth(virNetLibsshSessionPtr sess,
+ const char *keyfile,
+ const char *password)
+{
+ int ret;
+ virNetLibsshAuthMethodPtr auth;
+ char *pass = NULL;
+ char *file = NULL;
+
+ if (!keyfile) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("Key file path must be provided "
+ "for private key authentication"));
+ ret = -1;
+ goto error;
+ }
+
+ virObjectLock(sess);
+
+ if (VIR_STRDUP(file, keyfile) < 0 ||
+ VIR_STRDUP(pass, password) < 0) {
+ ret = -1;
+ goto error;
+ }
+
+ if (!(auth = virNetLibsshSessionAuthMethodNew(sess))) {
+ ret = -1;
+ goto error;
+ }
+
+ auth->password = pass;
+ auth->filename = file;
+ auth->method = VIR_NET_LIBSSH_AUTH_PRIVKEY;
+ auth->ssh_flags = SSH_AUTH_METHOD_PUBLICKEY;
+
+ ret = 0;
+
+ cleanup:
+ virObjectUnlock(sess);
+ return ret;
+
+ error:
+ VIR_DISPOSE_STRING(pass);
+ VIR_FREE(file);
+ goto cleanup;
+}
+
+int
+virNetLibsshSessionAuthAddKeyboardAuth(virNetLibsshSessionPtr sess,
+ int tries)
+{
+ int ret;
+ virNetLibsshAuthMethodPtr auth;
+
+ virObjectLock(sess);
+
+ if (!(auth = virNetLibsshSessionAuthMethodNew(sess))) {
+ ret = -1;
+ goto cleanup;
+ }
+
+ auth->tries = tries;
+ auth->method = VIR_NET_LIBSSH_AUTH_KEYBOARD_INTERACTIVE;
+ auth->ssh_flags = SSH_AUTH_METHOD_INTERACTIVE;
+
+ ret = 0;
+
+ cleanup:
+ virObjectUnlock(sess);
+ return ret;
+
+}
+
+int
+virNetLibsshSessionSetChannelCommand(virNetLibsshSessionPtr sess,
+ const char *command)
+{
+ int ret = 0;
+ virObjectLock(sess);
+
+ VIR_FREE(sess->channelCommand);
+
+ if (VIR_STRDUP(sess->channelCommand, command) < 0)
+ ret = -1;
+
+ virObjectUnlock(sess);
+ return ret;
+}
+
+int
+virNetLibsshSessionSetHostKeyVerification(virNetLibsshSessionPtr sess,
+ const char *hostname,
+ int port,
+ const char *hostsfile,
+ virNetLibsshHostkeyVerify opt)
+{
+ virObjectLock(sess);
+
+ sess->port = port;
+ sess->hostKeyVerify = opt;
+
+ VIR_FREE(sess->hostname);
+
+ if (VIR_STRDUP(sess->hostname, hostname) < 0)
+ goto error;
+
+ /* set the hostname */
+ if (ssh_options_set(sess->session, SSH_OPTIONS_HOST, sess->hostname) < 0)
+ goto error;
+
+ /* set the port */
+ if (port > 0) {
+ unsigned int portU = port;
+
+ if (ssh_options_set(sess->session, SSH_OPTIONS_PORT, &portU) < 0)
+ goto error;
+ }
+
+ /* set the known hosts file */
+ if (ssh_options_set(sess->session, SSH_OPTIONS_KNOWNHOSTS, hostsfile) < 0)
+ goto error;
+
+ VIR_FREE(sess->knownHostsFile);
+ if (VIR_STRDUP(sess->knownHostsFile, hostsfile) < 0)
+ goto error;
+
+ virObjectUnlock(sess);
+ return 0;
+
+ error:
+ virObjectUnlock(sess);
+ return -1;
+}
+
+/* allocate and initialize a libssh session object */
+virNetLibsshSessionPtr virNetLibsshSessionNew(const char *username)
+{
+ virNetLibsshSessionPtr sess = NULL;
+
+ if (virNetLibsshSessionInitialize() < 0)
+ goto error;
+
+ if (!(sess = virObjectLockableNew(virNetLibsshSessionClass)))
+ goto error;
+
+ /* initialize session data */
+ if (!(sess->session = ssh_new())) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("Failed to initialize libssh session"));
+ goto error;
+ }
+
+ if (VIR_STRDUP(sess->username, username) < 0)
+ goto error;
+
+ VIR_DEBUG("virNetLibsshSessionPtr: %p, ssh_session: %p",
+ sess, sess->session);
+
+ /* set blocking mode for libssh until handshake is complete */
+ ssh_set_blocking(sess->session, 1);
+
+ if (ssh_options_set(sess->session, SSH_OPTIONS_USER, sess->username) < 0)
+ goto error;
+
+ /* default states for config variables */
+ sess->state = VIR_NET_LIBSSH_STATE_NEW;
+ sess->hostKeyVerify = VIR_NET_LIBSSH_HOSTKEY_VERIFY_IGNORE;
+
+ return sess;
+
+ error:
+ virObjectUnref(sess);
+ return NULL;
+}
+
+int
+virNetLibsshSessionConnect(virNetLibsshSessionPtr sess,
+ int sock)
+{
+ int ret;
+ const char *errmsg;
+
+ VIR_DEBUG("sess=%p, sock=%d", sess, sock);
+
+ if (!sess || sess->state != VIR_NET_LIBSSH_STATE_NEW) {
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("Invalid virNetLibsshSessionPtr"));
+ return -1;
+ }
+
+ virObjectLock(sess);
+
+ /* check if configuration is valid */
+ if ((ret = virNetLibsshValidateConfig(sess)) < 0)
+ goto error;
+
+ /* read ~/.ssh/config */
+ if ((ret = ssh_options_parse_config(sess->session, NULL)) < 0)
+ goto error;
+
+ /* set the socket FD for the libssh session */
+ if ((ret = ssh_options_set(sess->session, SSH_OPTIONS_FD, &sock)) < 0)
+ goto error;
+
+ /* open session */
+ ret = ssh_connect(sess->session);
+ /* libssh is in blocking mode, so EAGAIN will never happen */
+ if (ret < 0) {
+ errmsg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_NO_CONNECT,
+ _("SSH session handshake failed: %s"),
+ errmsg);
+ goto error;
+ }
+
+ /* verify the SSH host key */
+ if ((ret = virNetLibsshCheckHostKey(sess)) != 0)
+ goto error;
+
+ /* authenticate */
+ if ((ret = virNetLibsshAuthenticate(sess)) != 0)
+ goto error;
+
+ /* open channel */
+ if ((ret = virNetLibsshOpenChannel(sess)) != 0)
+ goto error;
+
+ /* all set */
+ /* switch to nonblocking mode and return */
+ ssh_set_blocking(sess->session, 0);
+ sess->state = VIR_NET_LIBSSH_STATE_HANDSHAKE_COMPLETE;
+
+ virObjectUnlock(sess);
+ return ret;
+
+ error:
+ sess->state = VIR_NET_LIBSSH_STATE_ERROR;
+ virObjectUnlock(sess);
+ return ret;
+}
+
+/* do a read from a ssh channel, used instead of normal read on socket */
+ssize_t
+virNetLibsshChannelRead(virNetLibsshSessionPtr sess,
+ char *buf,
+ size_t len)
+{
+ int ret = -1;
+ ssize_t read_n = 0;
+
+ virObjectLock(sess);
+
+ if (sess->state != VIR_NET_LIBSSH_STATE_HANDSHAKE_COMPLETE) {
+ if (sess->state == VIR_NET_LIBSSH_STATE_ERROR_REMOTE)
+ virReportError(VIR_ERR_LIBSSH,
+ _("Remote program terminated "
+ "with non-zero code: %d"),
+ sess->channelCommandReturnValue);
+ else
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("Tried to write socket in error state"));
+
+ virObjectUnlock(sess);
+ return -1;
+ }
+
+ if (sess->bufUsed > 0) {
+ /* copy the rest (or complete) internal buffer to the output buffer */
+ memcpy(buf,
+ sess->rbuf + sess->bufStart,
+ len > sess->bufUsed ? sess->bufUsed : len);
+
+ if (len >= sess->bufUsed) {
+ read_n = sess->bufUsed;
+
+ sess->bufStart = 0;
+ sess->bufUsed = 0;
+ } else {
+ read_n = len;
+ sess->bufUsed -= len;
+ sess->bufStart += len;
+
+ goto success;
+ }
+ }
+
+ /* continue reading into the buffer supplied */
+ if (read_n < len) {
+ ret = ssh_channel_read_nonblocking(sess->channel,
+ buf + read_n,
+ len - read_n,
+ 0);
+
+ if (ret == SSH_EOF || (ret == 0 && ssh_channel_is_eof(sess->channel)))
+ goto eof;
+
+ if (ret == SSH_AGAIN)
+ goto success;
+
+ if (ret < 0)
+ goto error;
+
+ read_n += ret;
+ }
+
+ /* try to read something into the internal buffer */
+ if (sess->bufUsed == 0) {
+ ret = ssh_channel_read_nonblocking(sess->channel,
+ sess->rbuf,
+ VIR_NET_LIBSSH_BUFFER_SIZE,
+ 0);
+
+ if (ret == SSH_EOF || (ret == 0 && ssh_channel_is_eof(sess->channel)))
+ goto eof;
+
+ if (ret == SSH_AGAIN)
+ goto success;
+
+ if (ret < 0)
+ goto error;
+
+ sess->bufUsed = ret;
+ sess->bufStart = 0;
+ }
+
+ if (read_n == 0) {
+ /* get rid of data in stderr stream */
+ ret = ssh_channel_read_nonblocking(sess->channel,
+ sess->rbuf,
+ VIR_NET_LIBSSH_BUFFER_SIZE - 1,
+ 1);
+ if (ret > 0) {
+ sess->rbuf[ret] = '\0';
+ VIR_DEBUG("flushing stderr, data='%s'", sess->rbuf);
+ }
+ }
+
+ if (ssh_channel_is_eof(sess->channel)) {
+ eof:
+ if (ssh_channel_get_exit_status(sess->channel)) {
+ virReportError(VIR_ERR_LIBSSH,
+ _("Remote command terminated with non-zero code: %d"),
+ ssh_channel_get_exit_status(sess->channel));
+ sess->channelCommandReturnValue = ssh_channel_get_exit_status(sess->channel);
+ sess->state = VIR_NET_LIBSSH_STATE_ERROR_REMOTE;
+ virObjectUnlock(sess);
+ return -1;
+ }
+
+ sess->state = VIR_NET_LIBSSH_STATE_CLOSED;
+ virObjectUnlock(sess);
+ return -1;
+ }
+
+ success:
+ virObjectUnlock(sess);
+ return read_n;
+
+ error:
+ sess->state = VIR_NET_LIBSSH_STATE_ERROR;
+ virObjectUnlock(sess);
+ return ret;
+}
+
+ssize_t
+virNetLibsshChannelWrite(virNetLibsshSessionPtr sess,
+ const char *buf,
+ size_t len)
+{
+ ssize_t ret;
+
+ virObjectLock(sess);
+
+ if (sess->state != VIR_NET_LIBSSH_STATE_HANDSHAKE_COMPLETE) {
+ if (sess->state == VIR_NET_LIBSSH_STATE_ERROR_REMOTE)
+ virReportError(VIR_ERR_LIBSSH,
+ _("Remote program terminated with non-zero code: %d"),
+ sess->channelCommandReturnValue);
+ else
+ virReportError(VIR_ERR_LIBSSH, "%s",
+ _("Tried to write socket in error state"));
+ ret = -1;
+ goto cleanup;
+ }
+
+ if (ssh_channel_is_eof(sess->channel)) {
+ if (ssh_channel_get_exit_status(sess->channel)) {
+ virReportError(VIR_ERR_LIBSSH,
+ _("Remote program terminated with non-zero code: %d"),
+ ssh_channel_get_exit_status(sess->channel));
+ sess->state = VIR_NET_LIBSSH_STATE_ERROR_REMOTE;
+ sess->channelCommandReturnValue = ssh_channel_get_exit_status(sess->channel);
+
+ ret = -1;
+ goto cleanup;
+ }
+
+ sess->state = VIR_NET_LIBSSH_STATE_CLOSED;
+ ret = -1;
+ goto cleanup;
+ }
+
+ ret = ssh_channel_write(sess->channel, buf, len);
+ if (ret == SSH_AGAIN) {
+ ret = 0;
+ goto cleanup;
+ }
+
+ if (ret < 0) {
+ const char *msg;
+ sess->state = VIR_NET_LIBSSH_STATE_ERROR;
+ msg = ssh_get_error(sess->session);
+ virReportError(VIR_ERR_LIBSSH,
+ _("write failed: %s"), msg);
+ }
+
+ cleanup:
+ virObjectUnlock(sess);
+ return ret;
+}
+
+bool
+virNetLibsshSessionHasCachedData(virNetLibsshSessionPtr sess)
+{
+ bool ret;
+
+ if (!sess)
+ return false;
+
+ virObjectLock(sess);
+
+ ret = sess->bufUsed > 0;
+
+ virObjectUnlock(sess);
+ return ret;
+}
diff --git a/src/rpc/virnetlibsshsession.h b/src/rpc/virnetlibsshsession.h
new file mode 100644
index 0000000..aaf2f1c
--- /dev/null
+++ b/src/rpc/virnetlibsshsession.h
@@ -0,0 +1,78 @@
+/*
+ * virnetlibsshsession.h: ssh transport provider based on libssh
+ *
+ * Copyright (C) 2012-2016 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Author: Peter Krempa <pkrempa at redhat.com>
+ * Author: Pino Toscano <ptoscano at redhat.com>
+ */
+#ifndef __VIR_NET_LIBSSH_SESSION_H__
+# define __VIR_NET_LIBSSH_SESSION_H__
+
+# include "internal.h"
+# include "viruri.h"
+
+typedef struct _virNetLibsshSession virNetLibsshSession;
+typedef virNetLibsshSession *virNetLibsshSessionPtr;
+
+virNetLibsshSessionPtr virNetLibsshSessionNew(const char *username);
+void virNetLibsshSessionFree(virNetLibsshSessionPtr sess);
+
+typedef enum {
+ VIR_NET_LIBSSH_HOSTKEY_VERIFY_NORMAL,
+ VIR_NET_LIBSSH_HOSTKEY_VERIFY_AUTO_ADD,
+ VIR_NET_LIBSSH_HOSTKEY_VERIFY_IGNORE
+} virNetLibsshHostkeyVerify;
+
+int virNetLibsshSessionSetChannelCommand(virNetLibsshSessionPtr sess,
+ const char *command);
+
+int virNetLibsshSessionAuthSetCallback(virNetLibsshSessionPtr sess,
+ virConnectAuthPtr auth);
+
+int virNetLibsshSessionAuthAddPasswordAuth(virNetLibsshSessionPtr sess,
+ virURIPtr uri);
+
+int virNetLibsshSessionAuthAddAgentAuth(virNetLibsshSessionPtr sess);
+
+int virNetLibsshSessionAuthAddPrivKeyAuth(virNetLibsshSessionPtr sess,
+ const char *keyfile,
+ const char *password);
+
+int virNetLibsshSessionAuthAddKeyboardAuth(virNetLibsshSessionPtr sess,
+ int tries);
+
+int virNetLibsshSessionSetHostKeyVerification(virNetLibsshSessionPtr sess,
+ const char *hostname,
+ int port,
+ const char *hostsfile,
+ virNetLibsshHostkeyVerify opt);
+
+int virNetLibsshSessionConnect(virNetLibsshSessionPtr sess,
+ int sock);
+
+ssize_t virNetLibsshChannelRead(virNetLibsshSessionPtr sess,
+ char *buf,
+ size_t len);
+
+ssize_t virNetLibsshChannelWrite(virNetLibsshSessionPtr sess,
+ const char *buf,
+ size_t len);
+
+bool virNetLibsshSessionHasCachedData(virNetLibsshSessionPtr sess);
+
+#endif /* ___VIR_NET_LIBSSH_SESSION_H_ */
--
2.7.4
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