-#!/usr/bin/python
+#
#
-# Copyright (C) 2006, 2007 Google Inc.
+# Copyright (C) 2006, 2007, 2010, 2011 Google Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
import os
+import logging
+import re
-from ganeti import logger
from ganeti import utils
from ganeti import errors
from ganeti import constants
+from ganeti import netutils
+from ganeti import pathutils
+from ganeti import vcluster
-__all__ = ["SSHCall", "CopyFileToNode", "VerifyNodeHostname",
- "KNOWN_HOSTS_OPTS", "BATCH_MODE_OPTS", "ASK_KEY_OPTS"]
-
+def FormatParamikoFingerprint(fingerprint):
+ """Format paramiko PKey fingerprint.
-KNOWN_HOSTS_OPTS = [
- "-oGlobalKnownHostsFile=%s" % constants.SSH_KNOWN_HOSTS_FILE,
- "-oUserKnownHostsFile=/dev/null",
- ]
+ @type fingerprint: str
+ @param fingerprint: PKey fingerprint
+ @return: The string hex representation of the fingerprint
-# Note: BATCH_MODE conflicts with ASK_KEY
-BATCH_MODE_OPTS = [
- "-oEscapeChar=none",
- "-oBatchMode=yes",
- "-oStrictHostKeyChecking=yes",
- ]
+ """
+ assert len(fingerprint) % 2 == 0
+ return ":".join(re.findall(r"..", fingerprint.lower()))
-ASK_KEY_OPTS = [
- "-oStrictHostKeyChecking=ask",
- "-oEscapeChar=none",
- "-oHashKnownHosts=no",
- ]
+def GetUserFiles(user, mkdir=False):
+ """Return the paths of a user's ssh files.
-def BuildSSHCmd(hostname, user, command, batch=True, ask_key=False):
- """Build an ssh string to execute a command on a remote node.
+ The function will return a triplet (priv_key_path, pub_key_path,
+ auth_key_path) that are used for ssh authentication. Currently, the
+ keys used are DSA keys, so this function will return:
+ (~user/.ssh/id_dsa, ~user/.ssh/id_dsa.pub,
+ ~user/.ssh/authorized_keys).
- Args:
- hostname: the target host, string
- user: user to auth as
- command: the command
- batch: if true, ssh will run in batch mode with no prompting
- ask_key: if true, ssh will run with StrictHostKeyChecking=ask, so that
- we can connect to an unknown host (not valid in batch mode)
+ If the optional parameter mkdir is True, the ssh directory will be
+ created if it doesn't exist.
- Returns:
- The ssh call to run 'command' on the remote host.
+ Regardless of the mkdir parameters, the script will raise an error
+ if ~user/.ssh is not a directory.
"""
- argv = ["ssh", "-q"]
- argv.extend(KNOWN_HOSTS_OPTS)
- if batch:
- # if we are in batch mode, we can't ask the key
- if ask_key:
- raise errors.ProgrammerError("SSH call requested conflicting options")
- argv.extend(BATCH_MODE_OPTS)
- elif ask_key:
- argv.extend(ASK_KEY_OPTS)
- argv.extend(["%s@%s" % (user, hostname), command])
- return argv
-
-
-def SSHCall(hostname, user, command, batch=True, ask_key=False):
- """Execute a command on a remote node.
-
- This method has the same return value as `utils.RunCmd()`, which it
- uses to launch ssh.
-
- Args:
- hostname: the target host, string
- user: user to auth as
- command: the command
- batch: if true, ssh will run in batch mode with no prompting
- ask_key: if true, ssh will run with StrictHostKeyChecking=ask, so that
- we can connect to an unknown host (not valid in batch mode)
-
- Returns:
- `utils.RunResult` as for `utils.RunCmd()`
+ user_dir = utils.GetHomeDir(user)
+ if not user_dir:
+ raise errors.OpExecError("Cannot resolve home of user %s" % user)
+
+ ssh_dir = utils.PathJoin(user_dir, ".ssh")
+ if mkdir:
+ utils.EnsureDirs([(ssh_dir, constants.SECURE_DIR_MODE)])
+ elif not os.path.isdir(ssh_dir):
+ raise errors.OpExecError("Path %s is not a directory" % ssh_dir)
+
+ return [utils.PathJoin(ssh_dir, base)
+ for base in ["id_dsa", "id_dsa.pub", "authorized_keys"]]
+
+
+class SshRunner:
+ """Wrapper for SSH commands.
"""
- return utils.RunCmd(BuildSSHCmd(hostname, user, command, batch=batch, ask_key=ask_key))
+ def __init__(self, cluster_name, ipv6=False):
+ """Initializes this class.
+
+ @type cluster_name: str
+ @param cluster_name: name of the cluster
+ @type ipv6: bool
+ @param ipv6: If true, force ssh to use IPv6 addresses only
+
+ """
+ self.cluster_name = cluster_name
+ self.ipv6 = ipv6
+
+ def _BuildSshOptions(self, batch, ask_key, use_cluster_key,
+ strict_host_check, private_key=None, quiet=True):
+ """Builds a list with needed SSH options.
+
+ @param batch: same as ssh's batch option
+ @param ask_key: allows ssh to ask for key confirmation; this
+ parameter conflicts with the batch one
+ @param use_cluster_key: if True, use the cluster name as the
+ HostKeyAlias name
+ @param strict_host_check: this makes the host key checking strict
+ @param private_key: use this private key instead of the default
+ @param quiet: whether to enable -q to ssh
+
+ @rtype: list
+ @return: the list of options ready to use in L{utils.process.RunCmd}
+
+ """
+ options = [
+ "-oEscapeChar=none",
+ "-oHashKnownHosts=no",
+ "-oGlobalKnownHostsFile=%s" % pathutils.SSH_KNOWN_HOSTS_FILE,
+ "-oUserKnownHostsFile=/dev/null",
+ "-oCheckHostIp=no",
+ ]
+
+ if use_cluster_key:
+ options.append("-oHostKeyAlias=%s" % self.cluster_name)
+
+ if quiet:
+ options.append("-q")
+
+ if private_key:
+ options.append("-i%s" % private_key)
+
+ # TODO: Too many boolean options, maybe convert them to more descriptive
+ # constants.
+
+ # Note: ask_key conflicts with batch mode
+ if batch:
+ if ask_key:
+ raise errors.ProgrammerError("SSH call requested conflicting options")
+
+ options.append("-oBatchMode=yes")
+
+ if strict_host_check:
+ options.append("-oStrictHostKeyChecking=yes")
+ else:
+ options.append("-oStrictHostKeyChecking=no")
+
+ else:
+ # non-batch mode
+
+ if ask_key:
+ options.append("-oStrictHostKeyChecking=ask")
+ elif strict_host_check:
+ options.append("-oStrictHostKeyChecking=yes")
+ else:
+ options.append("-oStrictHostKeyChecking=no")
+ if self.ipv6:
+ options.append("-6")
-def CopyFileToNode(node, filename):
- """Copy a file to another node with scp.
+ return options
- Args:
- node: node in the cluster
- filename: absolute pathname of a local file
+ def BuildCmd(self, hostname, user, command, batch=True, ask_key=False,
+ tty=False, use_cluster_key=True, strict_host_check=True,
+ private_key=None, quiet=True):
+ """Build an ssh command to execute a command on a remote node.
- Returns:
- success: True/False
+ @param hostname: the target host, string
+ @param user: user to auth as
+ @param command: the command
+ @param batch: if true, ssh will run in batch mode with no prompting
+ @param ask_key: if true, ssh will run with
+ StrictHostKeyChecking=ask, so that we can connect to an
+ unknown host (not valid in batch mode)
+ @param use_cluster_key: whether to expect and use the
+ cluster-global SSH key
+ @param strict_host_check: whether to check the host's SSH key at all
+ @param private_key: use this private key instead of the default
+ @param quiet: whether to enable -q to ssh
+
+ @return: the ssh call to run 'command' on the remote host.
+
+ """
+ argv = [constants.SSH]
+ argv.extend(self._BuildSshOptions(batch, ask_key, use_cluster_key,
+ strict_host_check, private_key,
+ quiet=quiet))
+ if tty:
+ argv.extend(["-t", "-t"])
+
+ argv.append("%s@%s" % (user, hostname))
+
+ # Insert variables for virtual nodes
+ argv.extend("export %s=%s;" %
+ (utils.ShellQuote(name), utils.ShellQuote(value))
+ for (name, value) in
+ vcluster.EnvironmentForHost(hostname).items())
+
+ argv.append(command)
+
+ return argv
+
+ def Run(self, *args, **kwargs):
+ """Runs a command on a remote node.
- """
- if not os.path.isfile(filename):
- logger.Error("file %s does not exist" % (filename))
- return False
+ This method has the same return value as `utils.RunCmd()`, which it
+ uses to launch ssh.
- if not os.path.isabs(filename):
- logger.Error("file %s must be an absolute path" % (filename))
- return False
+ Args: see SshRunner.BuildCmd.
- command = ["scp", "-q", "-p"]
- command.extend(KNOWN_HOSTS_OPTS)
- command.extend(BATCH_MODE_OPTS)
- command.append(filename)
- command.append("%s:%s" % (node, filename))
+ @rtype: L{utils.process.RunResult}
+ @return: the result as from L{utils.process.RunCmd()}
- result = utils.RunCmd(command)
+ """
+ return utils.RunCmd(self.BuildCmd(*args, **kwargs))
- if result.failed:
- logger.Error("copy to node %s failed (%s) error %s,"
- " command was %s" %
- (node, result.fail_reason, result.output, result.cmd))
+ def CopyFileToNode(self, node, filename):
+ """Copy a file to another node with scp.
- return not result.failed
+ @param node: node in the cluster
+ @param filename: absolute pathname of a local file
+ @rtype: boolean
+ @return: the success of the operation
-def VerifyNodeHostname(node):
- """Verify hostname consistency via SSH.
+ """
+ if not os.path.isabs(filename):
+ logging.error("File %s must be an absolute path", filename)
+ return False
+ if not os.path.isfile(filename):
+ logging.error("File %s does not exist", filename)
+ return False
- This functions connects via ssh to a node and compares the hostname
- reported by the node to the name with have (the one that we
- connected to).
+ command = [constants.SCP, "-p"]
+ command.extend(self._BuildSshOptions(True, False, True, True))
+ command.append(filename)
+ if netutils.IP6Address.IsValid(node):
+ node = netutils.FormatAddress((node, None))
- This is used to detect problems in ssh known_hosts files
- (conflicting known hosts) and incosistencies between dns/hosts
- entries and local machine names
+ command.append("%s:%s" % (node, vcluster.ExchangeNodeRoot(node, filename)))
- Args:
- node: nodename of a host to check. can be short or full qualified hostname
+ result = utils.RunCmd(command)
- Returns:
- (success, detail)
- where
- success: True/False
- detail: String with details
+ if result.failed:
+ logging.error("Copy to node %s failed (%s) error '%s',"
+ " command was '%s'",
+ node, result.fail_reason, result.output, result.cmd)
- """
- retval = SSHCall(node, 'root', 'hostname')
+ return not result.failed
+
+ def VerifyNodeHostname(self, node):
+ """Verify hostname consistency via SSH.
- if retval.failed:
- msg = "ssh problem"
- output = retval.output
- if output:
- msg += ": %s" % output
- return False, msg
+ This functions connects via ssh to a node and compares the hostname
+ reported by the node to the name with have (the one that we
+ connected to).
- remotehostname = retval.stdout.strip()
+ This is used to detect problems in ssh known_hosts files
+ (conflicting known hosts) and inconsistencies between dns/hosts
+ entries and local machine names
- if not remotehostname or remotehostname != node:
- return False, "hostname mismatch, got %s" % remotehostname
+ @param node: nodename of a host to check; can be short or
+ full qualified hostname
- return True, "host matches"
+ @return: (success, detail), where:
+ - success: True/False
+ - detail: string with details
+
+ """
+ cmd = ("if test -z \"$GANETI_HOSTNAME\"; then"
+ " hostname --fqdn;"
+ "else"
+ " echo \"$GANETI_HOSTNAME\";"
+ "fi")
+ retval = self.Run(node, constants.SSH_LOGIN_USER, cmd, quiet=False)
+
+ if retval.failed:
+ msg = "ssh problem"
+ output = retval.output
+ if output:
+ msg += ": %s" % output
+ else:
+ msg += ": %s (no output)" % retval.fail_reason
+ logging.error("Command %s failed: %s", retval.cmd, msg)
+ return False, msg
+
+ remotehostname = retval.stdout.strip()
+
+ if not remotehostname or remotehostname != node:
+ if node.startswith(remotehostname + "."):
+ msg = "hostname not FQDN"
+ else:
+ msg = "hostname mismatch"
+ return False, ("%s: expected %s but got %s" %
+ (msg, node, remotehostname))
+
+ return True, "host matches"
+
+
+def WriteKnownHostsFile(cfg, file_name):
+ """Writes the cluster-wide equally known_hosts file.
+
+ """
+ utils.WriteFile(file_name, mode=0600,
+ data="%s ssh-rsa %s\n" % (cfg.GetClusterName(),
+ cfg.GetHostKey()))