Port apache/cloudstack#1533 that converts pacthviasocket to python

Original commits:
 * 0acd3c1: Convert patchviasocket to python (removes perl dependency for KVM agent)
 * 751d355: patchviasocket improve error handling

cosmic-core/plugins/hypervisor/kvm/src/main/java/com/cloud/hypervisor/kvm/resource/LibvirtComputingResourceProperties.java

@@ -545,7 +545,7 @@ public static class Constants {
         public static final String DEFAULT_VM_RNG_PATH = "/dev/random";
         public static final String SCRIPT_MODIFY_VLAN = "modifyvlan.sh";
         public static final String SCRIPT_VERSIONS = "versions.sh";
-        public static final String SCRIPT_PATCH_VIA_SOCKET = "patchviasocket.pl";
+        public static final String SCRIPT_PATCH_VIA_SOCKET = "patchviasocket.py";
         public static final String SCRIPT_KVM_HEART_BEAT = "kvmheartbeat.sh";
         public static final String SCRIPT_CREATE_VM = "createvm.sh";
         public static final String SCRIPT_MANAGE_SNAPSHOT = "managesnapshot.sh";

cosmic-core/scripts/src/main/resources/scripts/vm/hypervisor/kvm/patchviasocket.py

@@ -0,0 +1,76 @@
+#!/usr/bin/env python
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+#
+# This script connects to the system vm socket and writes the
+# authorized_keys and cmdline data to it. The system VM then
+# reads it from /dev/vport0p1 in cloud_early_config
+#
+
+import argparse
+import os
+import socket
+
+SOCK_FILE = "/var/lib/libvirt/qemu/{name}.agent"
+PUB_KEY_FILE = "/root/.ssh/id_rsa.pub.cloud"
+MESSAGE = "pubkey:{key}\ncmdline:{cmdline}\n"
+
+
+def send_to_socket(sock_file, key_file, cmdline):
+    if not os.path.exists(key_file):
+        print("ERROR: ssh public key not found on host at {0}".format(key_file))
+        return 1
+
+    try:
+        with open(key_file, "r") as f:
+            pub_key = f.read()
+    except IOError as e:
+        print("ERROR: unable to open {0} - {1}".format(key_file, e.strerror))
+        return 1
+
+    # Keep old substitution from perl code:
+    cmdline = cmdline.replace("%", " ")
+
+    msg = MESSAGE.format(key=pub_key, cmdline=cmdline)
+
+    if not os.path.exists(sock_file):
+        print("ERROR: {0} socket not found".format(sock_file))
+        return 1
+
+    try:
+        s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+        s.connect(sock_file)
+        s.sendall(msg)
+        s.close()
+    except IOError as e:
+        print("ERROR: unable to connect to {0} - {1}".format(sock_file, e.strerror))
+        return 1
+
+    return 0    # Success
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Send configuration to system VM socket")
+    parser.add_argument("-n", "--name", required=True, help="Name of VM")
+    parser.add_argument("-p", "--cmdline", required=True, help="Command line")
+
+    arguments = parser.parse_args()
+
+    socket_file = SOCK_FILE.format(name=arguments.name)
+
+    exit(send_to_socket(socket_file, PUB_KEY_FILE, arguments.cmdline))

cosmic-core/scripts/src/test/resources/scripts/vm/hypervisor/kvm/test_patchviasocket.py

@@ -0,0 +1,144 @@
+#!/usr/bin/env python
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+import patchviasocket
+
+import getpass
+import os
+import socket
+import tempfile
+import time
+import threading
+import unittest
+
+KEY_DATA = "I luv\nCloudStack\n"
+CMD_DATA = "/run/this-for-me --please=TRUE! very%quickly"
+NON_EXISTING_FILE = "must-not-exist"
+
+
+def write_key_file():
+    _, tmpfile = tempfile.mkstemp(".sck")
+    with open(tmpfile, "w") as f:
+        f.write(KEY_DATA)
+    return tmpfile
+
+
+class SocketThread(threading.Thread):
+    def __init__(self):
+        super(SocketThread, self).__init__()
+        self._data = ""
+        self._folder = tempfile.mkdtemp(".sck")
+        self._file = os.path.join(self._folder, "socket")
+        self._ready = False
+
+    def data(self):
+        return self._data
+
+    def file(self):
+        return self._file
+
+    def wait_until_ready(self):
+        while not self._ready:
+            time.sleep(0.050)
+
+    def run(self):
+        TIMEOUT = 0.314     # Very short time for tests that don't write to socket.
+        MAX_SIZE = 10 * 1024
+
+        s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+        try:
+            s.bind(self._file)
+            s.listen(1)
+            s.settimeout(TIMEOUT)
+            try:
+                self._ready = True
+                client, address = s.accept()
+                self._data = client.recv(MAX_SIZE)
+                client.close()
+            except socket.timeout:
+                pass
+        finally:
+            s.close()
+            os.remove(self._file)
+            os.rmdir(self._folder)
+
+
+class TestPatchViaSocket(unittest.TestCase):
+    def setUp(self):
+        self._key_file = write_key_file()
+
+        self._unreadable = write_key_file()
+        os.chmod(self._unreadable, 0)
+
+        self.assertFalse(os.path.exists(NON_EXISTING_FILE))
+        self.assertNotEqual("root", getpass.getuser(), "must be non-root user (to test access denied errors)")
+
+    def tearDown(self):
+        os.remove(self._key_file)
+        os.remove(self._unreadable)
+
+    def test_write_to_socket(self):
+        reader = SocketThread()
+        reader.start()
+        reader.wait_until_ready()
+        self.assertEquals(0, patchviasocket.send_to_socket(reader.file(), self._key_file, CMD_DATA))
+        reader.join()
+        data = reader.data()
+        self.assertIn(KEY_DATA, data)
+        self.assertIn(CMD_DATA.replace("%", " "), data)
+        self.assertNotIn("LUV", data)
+        self.assertNotIn("very%quickly", data)  # Testing substitution
+
+    def test_host_key_error(self):
+        reader = SocketThread()
+        reader.start()
+        reader.wait_until_ready()
+        self.assertEquals(1, patchviasocket.send_to_socket(reader.file(), NON_EXISTING_FILE, CMD_DATA))
+        reader.join()   # timeout
+
+    def test_host_key_access_denied(self):
+        reader = SocketThread()
+        reader.start()
+        reader.wait_until_ready()
+        self.assertEquals(1, patchviasocket.send_to_socket(reader.file(), self._unreadable, CMD_DATA))
+        reader.join()   # timeout
+
+    def test_nonexistant_socket_error(self):
+        reader = SocketThread()
+        reader.start()
+        reader.wait_until_ready()
+        self.assertEquals(1, patchviasocket.send_to_socket(NON_EXISTING_FILE, self._key_file, CMD_DATA))
+        reader.join()   # timeout
+
+    def test_invalid_socket_error(self):
+        reader = SocketThread()
+        reader.start()
+        reader.wait_until_ready()
+        self.assertEquals(1, patchviasocket.send_to_socket(self._key_file, self._key_file, CMD_DATA))
+        reader.join()   # timeout
+
+    def test_access_denied_socket_error(self):
+        reader = SocketThread()
+        reader.start()
+        reader.wait_until_ready()
+        self.assertEquals(1, patchviasocket.send_to_socket(self._unreadable, self._key_file, CMD_DATA))
+        reader.join()   # timeout
+
+
+if __name__ == '__main__':
+    unittest.main()