jaegonkim | dcf7c82 | 2019-02-06 15:00:14 +0900 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2019-present Open Networking Foundation |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package org.onosproject.ofoverlay.impl.util; |
| 17 | |
| 18 | import com.jcraft.jsch.Channel; |
| 19 | import com.jcraft.jsch.ChannelSftp; |
| 20 | import com.jcraft.jsch.JSch; |
| 21 | import com.jcraft.jsch.JSchException; |
| 22 | import com.jcraft.jsch.KeyPair; |
| 23 | import com.jcraft.jsch.Session; |
| 24 | import com.jcraft.jsch.SftpATTRS; |
| 25 | import com.jcraft.jsch.SftpException; |
| 26 | import org.onlab.packet.IpAddress; |
| 27 | import org.slf4j.Logger; |
| 28 | |
| 29 | import java.io.File; |
| 30 | import java.io.FileInputStream; |
| 31 | import java.io.IOException; |
| 32 | import java.nio.file.Files; |
| 33 | import java.nio.file.Paths; |
| 34 | import java.util.stream.Collectors; |
| 35 | import java.util.stream.Stream; |
| 36 | |
| 37 | import static org.slf4j.LoggerFactory.getLogger; |
| 38 | |
| 39 | /** |
| 40 | * Class for SSH key exchange. |
| 41 | */ |
| 42 | public class SshkeyExchange { |
| 43 | |
| 44 | protected static final Logger log = getLogger(SshkeyExchange.class); |
| 45 | private static final String HOME_ENV = System.getProperty("user.home"); |
| 46 | private static final String USER_ENV = System.getProperty("user.name"); |
| 47 | private static final String PUBLIC_KEY = "/.ssh/id_rsa.pub"; |
| 48 | private static final String PRIVATE_KEY = "/.ssh/id_rsa"; |
| 49 | private static final String SFTP_CHANNEL = "sftp"; |
| 50 | private static final String SSH_HOME = "/.ssh/"; |
| 51 | private static final String SSH_AUTH_KEY = "/.ssh/authorized_keys"; |
| 52 | private static final int SFTPPORT = 22; |
| 53 | private static final int DIR_PER = 448; |
| 54 | private static final int FILE_PER = 384; |
| 55 | private static final int KEY_SIZE = 2048; |
| 56 | private static final int DEFAULT_SESSION_TIMEOUT = 30000; // milliseconds |
| 57 | |
| 58 | private Session getJschSession(String user, String host, String password) { |
| 59 | java.util.Properties config = new java.util.Properties(); |
| 60 | config.put("StrictHostKeyChecking", "no"); |
| 61 | Session session; |
| 62 | try { |
| 63 | session = new JSch().getSession(user, host, SFTPPORT); |
| 64 | session.setPassword(password); |
| 65 | session.setConfig(config); |
| 66 | } catch (JSchException e) { |
| 67 | log.error("Exception in getJschSession", e); |
| 68 | return null; |
| 69 | } |
| 70 | |
| 71 | return session; |
| 72 | } |
| 73 | |
| 74 | private boolean generateKeyPair() { |
| 75 | KeyPair kpair; |
| 76 | StringBuilder command = new StringBuilder() |
| 77 | .append("chmod 600 ") |
| 78 | .append(HOME_ENV) |
| 79 | .append(PRIVATE_KEY); |
| 80 | try { |
| 81 | kpair = KeyPair.genKeyPair(new JSch(), KeyPair.RSA, KEY_SIZE); |
| 82 | kpair.writePrivateKey(HOME_ENV + PRIVATE_KEY); |
| 83 | kpair.writePublicKey(HOME_ENV + PUBLIC_KEY, USER_ENV); |
| 84 | Runtime.getRuntime().exec(command.toString()); |
| 85 | kpair.dispose(); |
| 86 | } catch (JSchException | IOException e) { |
| 87 | log.error("Exception in generateKeyPair", e); |
| 88 | return false; |
| 89 | } |
| 90 | return true; |
| 91 | } |
| 92 | |
| 93 | /** |
| 94 | * Exchanges SSH key. |
| 95 | * @param host SSH server host |
| 96 | * @param user user |
| 97 | * @param password password |
| 98 | * @return SSH key exchange success or not |
| 99 | */ |
| 100 | public boolean sshAutoKeyExchange(IpAddress host, String user, String password) { |
| 101 | |
| 102 | Session session = getJschSession(user, host.toString(), password); |
| 103 | boolean returnFlag; |
| 104 | File publickeyPath = new File(HOME_ENV + PUBLIC_KEY); |
| 105 | if (session == null) { |
| 106 | log.error("Error While establishing SFTP connection with {}", host.toString()); |
| 107 | return false; |
| 108 | } |
| 109 | Channel channel; |
| 110 | String remoteHome; |
| 111 | ChannelSftp sftp; |
| 112 | FileInputStream fis = null; |
| 113 | SftpATTRS attrs = null; |
| 114 | try { |
| 115 | session.connect(DEFAULT_SESSION_TIMEOUT); |
| 116 | channel = session.openChannel(SFTP_CHANNEL); |
| 117 | if (channel == null) { |
| 118 | log.error("SFTP channel open failed for {}", host.toString()); |
| 119 | return false; |
| 120 | } |
| 121 | channel.connect(); |
| 122 | sftp = (ChannelSftp) channel; |
| 123 | remoteHome = sftp.getHome(); |
| 124 | // checking key pair existance |
| 125 | |
| 126 | if (!publickeyPath.exists()) { |
| 127 | File dirs = new File(HOME_ENV + SSH_HOME); |
| 128 | if (!dirs.exists() && !dirs.mkdirs()) { |
| 129 | log.error("{} not exists and unable to create ", dirs.getPath()); |
| 130 | return false; |
| 131 | } else if (!generateKeyPair()) { |
| 132 | log.error("SSH Key pair generation failed"); |
| 133 | return false; |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | // checking for authenticate_keys file existance |
| 138 | fis = new FileInputStream(publickeyPath); |
| 139 | try { |
| 140 | sftp.lstat(remoteHome + SSH_HOME); |
| 141 | } catch (SftpException e) { |
| 142 | sftp.mkdir(remoteHome + SSH_HOME); |
| 143 | sftp.chmod(700, remoteHome + SSH_HOME); |
| 144 | } |
| 145 | try { |
| 146 | attrs = sftp.lstat(remoteHome + SSH_AUTH_KEY); |
| 147 | } catch (SftpException e) { |
| 148 | log.info("authorized_keys file does not exist at remote device ," |
| 149 | + "a new file will be created"); |
| 150 | } |
| 151 | |
| 152 | if (attrs != null) { |
| 153 | sftp.get(remoteHome + SSH_AUTH_KEY, HOME_ENV + "/tempauthorized_keys"); |
| 154 | |
| 155 | String pubKey; |
| 156 | try (Stream<String> st = Files.lines(Paths.get(HOME_ENV + PUBLIC_KEY))) { |
| 157 | pubKey = st.collect(Collectors.joining()); |
| 158 | } |
| 159 | |
| 160 | String authKey; |
| 161 | try (Stream<String> st = Files.lines(Paths.get(HOME_ENV + "/tempauthorized_keys"))) { |
| 162 | authKey = st.collect(Collectors.joining()); |
| 163 | } |
| 164 | |
| 165 | if (authKey.contains(pubKey)) { |
| 166 | log.info("Skipping key append to server as Key is already added"); |
| 167 | } else { |
| 168 | sftp.put(fis, remoteHome + SSH_AUTH_KEY, ChannelSftp.APPEND); |
| 169 | log.info("Public key appended to server"); |
| 170 | } |
| 171 | } else { |
| 172 | |
| 173 | sftp.put(fis, remoteHome + SSH_AUTH_KEY, ChannelSftp.APPEND); |
| 174 | // Give proper permission to file and directory. |
| 175 | sftp.chmod(DIR_PER, remoteHome + SSH_HOME); |
| 176 | sftp.chmod(FILE_PER, remoteHome + SSH_AUTH_KEY); |
| 177 | log.info("Public key appended to server"); |
| 178 | } |
| 179 | |
| 180 | sftp.exit(); |
| 181 | session.disconnect(); |
| 182 | returnFlag = true; |
| 183 | } catch (JSchException | SftpException | IOException e) { |
| 184 | log.error("Exception occured because of {} ", e); |
| 185 | returnFlag = false; |
| 186 | } finally { |
| 187 | if (fis != null) { |
| 188 | try { |
| 189 | fis.close(); |
| 190 | } catch (IOException e) { |
| 191 | log.info("Error closing public key file"); |
| 192 | } |
| 193 | } |
| 194 | } |
| 195 | return returnFlag; |
| 196 | |
| 197 | } |
| 198 | } |