org.apache.sshd.common.config.SshConfigFileReader Maven / Gradle / Ivy
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* 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,
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* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.sshd.common.config;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.Properties;
import java.util.function.Function;
import org.apache.sshd.common.BuiltinFactory;
import org.apache.sshd.common.NamedFactory;
import org.apache.sshd.common.PropertyResolver;
import org.apache.sshd.common.cipher.BuiltinCiphers;
import org.apache.sshd.common.cipher.Cipher;
import org.apache.sshd.common.compression.BuiltinCompressions;
import org.apache.sshd.common.compression.Compression;
import org.apache.sshd.common.compression.CompressionFactory;
import org.apache.sshd.common.helpers.AbstractFactoryManager;
import org.apache.sshd.common.kex.BuiltinDHFactories;
import org.apache.sshd.common.kex.DHFactory;
import org.apache.sshd.common.kex.KeyExchange;
import org.apache.sshd.common.mac.BuiltinMacs;
import org.apache.sshd.common.mac.Mac;
import org.apache.sshd.common.signature.BuiltinSignatures;
import org.apache.sshd.common.signature.Signature;
import org.apache.sshd.common.util.GenericUtils;
import org.apache.sshd.common.util.ValidateUtils;
/**
* Reads and interprets some useful configurations from an OpenSSH
* configuration file.
*
* @author Apache MINA SSHD Project
* @see ssh_config(5)
*/
public final class SshConfigFileReader {
private SshConfigFileReader() {
throw new UnsupportedOperationException("No instance allowed");
}
/**
* @param props The {@link PropertyResolver} - ignored if {@code null}/empty
* @return A {@code ParseResult} of all the {@link NamedFactory}-ies
* whose name appears in the string and represent a built-in cipher.
* Any unknown name is ignored. The order of the returned result
* is the same as the original order - bar the unknown ciphers.
* Note: it is up to caller to ensure that the lists do not
* contain duplicates
* @see ConfigFileReaderSupport#CIPHERS_CONFIG_PROP CIPHERS_CONFIG_PROP
* @see BuiltinCiphers#parseCiphersList(String)
*/
public static BuiltinCiphers.ParseResult getCiphers(PropertyResolver props) {
return BuiltinCiphers.parseCiphersList(
(props == null) ? null : props.getString(ConfigFileReaderSupport.CIPHERS_CONFIG_PROP));
}
/**
* @param props The {@link PropertyResolver} - ignored if {@code null}/empty
* @return A {@code ParseResult} of all the {@link NamedFactory}-ies
* whose name appears in the string and represent a built-in MAC. Any
* unknown name is ignored. The order of the returned result
* is the same as the original order - bar the unknown MACs.
* Note: it is up to caller to ensure that the list does not
* contain duplicates
* @see ConfigFileReaderSupport#MACS_CONFIG_PROP MACS_CONFIG_PROP
* @see BuiltinMacs#parseMacsList(String)
*/
public static BuiltinMacs.ParseResult getMacs(PropertyResolver props) {
return BuiltinMacs.parseMacsList(
(props == null) ? null : props.getString(ConfigFileReaderSupport.MACS_CONFIG_PROP));
}
/**
* @param props The {@link PropertyResolver} - ignored if {@code null}/empty
* @return A {@code ParseResult} of all the {@link NamedFactory}
* whose name appears in the string and represent a built-in signature. Any
* unknown name is ignored. The order of the returned result is the
* same as the original order - bar the unknown signatures. Note: it
* is up to caller to ensure that the list does not contain duplicates
* @see ConfigFileReaderSupport#HOST_KEY_ALGORITHMS_CONFIG_PROP HOST_KEY_ALGORITHMS_CONFIG_PROP
* @see BuiltinSignatures#parseSignatureList(String)
*/
public static BuiltinSignatures.ParseResult getSignatures(PropertyResolver props) {
return BuiltinSignatures.parseSignatureList(
(props == null) ? null : props.getString(ConfigFileReaderSupport.HOST_KEY_ALGORITHMS_CONFIG_PROP));
}
/**
* @param props The {@link PropertyResolver} - ignored if {@code null}/empty
* @return A {@code ParseResult} of all the {@link DHFactory}-ies
* whose name appears in the string and represent a built-in value. Any
* unknown name is ignored. The order of the returned result is the
* same as the original order - bar the unknown ones. Note: it is
* up to caller to ensure that the list does not contain duplicates
* @see ConfigFileReaderSupport#KEX_ALGORITHMS_CONFIG_PROP KEX_ALGORITHMS_CONFIG_PROP
* @see BuiltinDHFactories#parseDHFactoriesList(String)
*/
public static BuiltinDHFactories.ParseResult getKexFactories(PropertyResolver props) {
return BuiltinDHFactories.parseDHFactoriesList(
(props == null) ? null : props.getString(ConfigFileReaderSupport.KEX_ALGORITHMS_CONFIG_PROP));
}
/**
* @param props The {@link PropertyResolver} - ignored if {@code null}/empty
* @return The matching {@link NamedFactory} for the configured value.
* {@code null} if no configuration or unknown name specified
* @see ConfigFileReaderSupport#COMPRESSION_PROP COMPRESSION_PROP
*/
public static CompressionFactory getCompression(PropertyResolver props) {
return CompressionConfigValue.fromName(
(props == null) ? null : props.getString(ConfigFileReaderSupport.COMPRESSION_PROP));
}
/**
* Configures an {@link AbstractFactoryManager} with the values read from
* some configuration. Currently it configures:
*
* - The {@link Cipher}s - via the {@link ConfigFileReaderSupport#CIPHERS_CONFIG_PROP}
* - The {@link Mac}s - via the {@link ConfigFileReaderSupport#MACS_CONFIG_PROP}
* - The {@link Signature}s - via the {@link ConfigFileReaderSupport#HOST_KEY_ALGORITHMS_CONFIG_PROP}
* - The {@link Compression} - via the {@link ConfigFileReaderSupport#COMPRESSION_PROP}
*
*
* @param The generic factory manager
* @param manager The {@link AbstractFactoryManager} to configure
* @param props The {@link PropertyResolver} to use for configuration - Note:
* if any known configuration value has a default and does not appear in the
* properties, the default is used
* @param lenient If {@code true} then any unknown configuration values are ignored.
* Otherwise an {@link IllegalArgumentException} is thrown
* @param ignoreUnsupported filter out unsupported configuration values (e.g., ciphers,
* key exchanges, etc..). Note: if after filtering out all the unknown
* or unsupported values there is an empty configuration exception is thrown
* @return The configured manager
*/
public static M configure(
M manager, PropertyResolver props, boolean lenient, boolean ignoreUnsupported) {
configureCiphers(manager, props, lenient, ignoreUnsupported);
configureSignatures(manager, props, lenient, ignoreUnsupported);
configureMacs(manager, props, lenient, ignoreUnsupported);
configureCompression(manager, props, lenient, ignoreUnsupported);
return manager;
}
public static M configureCiphers(M manager, PropertyResolver props, boolean lenient, boolean ignoreUnsupported) {
Objects.requireNonNull(props, "No properties to configure");
return configureCiphers(manager,
props.getStringProperty(ConfigFileReaderSupport.CIPHERS_CONFIG_PROP, ConfigFileReaderSupport.DEFAULT_CIPHERS),
lenient, ignoreUnsupported);
}
public static M configureCiphers(
M manager, String value, boolean lenient, boolean ignoreUnsupported) {
Objects.requireNonNull(manager, "No manager to configure");
BuiltinCiphers.ParseResult result = BuiltinCiphers.parseCiphersList(value);
Collection unsupported = result.getUnsupportedFactories();
ValidateUtils.checkTrue(lenient || GenericUtils.isEmpty(unsupported), "Unsupported cipher(s) (%s) in %s", unsupported, value);
List> factories =
BuiltinFactory.setUpFactories(ignoreUnsupported, result.getParsedFactories());
manager.setCipherFactories(ValidateUtils.checkNotNullAndNotEmpty(factories, "No known/unsupported ciphers(s): %s", value));
return manager;
}
public static M configureSignatures(M manager, PropertyResolver props, boolean lenient, boolean ignoreUnsupported) {
Objects.requireNonNull(props, "No properties to configure");
return configureSignatures(manager,
props.getStringProperty(ConfigFileReaderSupport.HOST_KEY_ALGORITHMS_CONFIG_PROP, ConfigFileReaderSupport.DEFAULT_HOST_KEY_ALGORITHMS),
lenient, ignoreUnsupported);
}
public static M configureSignatures(
M manager, String value, boolean lenient, boolean ignoreUnsupported) {
Objects.requireNonNull(manager, "No manager to configure");
BuiltinSignatures.ParseResult result = BuiltinSignatures.parseSignatureList(value);
Collection unsupported = result.getUnsupportedFactories();
ValidateUtils.checkTrue(lenient || GenericUtils.isEmpty(unsupported), "Unsupported signatures (%s) in %s", unsupported, value);
List> factories =
BuiltinFactory.setUpFactories(ignoreUnsupported, result.getParsedFactories());
manager.setSignatureFactories(ValidateUtils.checkNotNullAndNotEmpty(factories, "No known/supported signatures: %s", value));
return manager;
}
public static M configureMacs(
M manager, PropertyResolver resolver, boolean lenient, boolean ignoreUnsupported) {
Objects.requireNonNull(resolver, "No properties to configure");
return configureMacs(manager,
resolver.getStringProperty(ConfigFileReaderSupport.MACS_CONFIG_PROP, ConfigFileReaderSupport.DEFAULT_MACS),
lenient, ignoreUnsupported);
}
public static M configureMacs(
M manager, String value, boolean lenient, boolean ignoreUnsupported) {
Objects.requireNonNull(manager, "No manager to configure");
BuiltinMacs.ParseResult result = BuiltinMacs.parseMacsList(value);
Collection unsupported = result.getUnsupportedFactories();
ValidateUtils.checkTrue(lenient || GenericUtils.isEmpty(unsupported), "Unsupported MAC(s) (%s) in %s", unsupported, value);
List> factories =
BuiltinFactory.setUpFactories(ignoreUnsupported, result.getParsedFactories());
manager.setMacFactories(ValidateUtils.checkNotNullAndNotEmpty(factories, "No known/supported MAC(s): %s", value));
return manager;
}
/**
* @param The generic factory manager
* @param manager The {@link AbstractFactoryManager} to set up (may not be {@code null})
* @param props The (non-{@code null}) {@link PropertyResolver} containing the configuration
* @param lenient If {@code true} then any unknown/unsupported configuration
* values are ignored. Otherwise an {@link IllegalArgumentException} is thrown
* @param xformer A {@link Function} to convert the configured {@link DHFactory}-ies
* to {@link NamedFactory}-ies of {@link KeyExchange}
* @param ignoreUnsupported Filter out any un-supported configurations - Note:
* if after ignoring the unknown and un-supported values the result is an empty
* list of factories and exception is thrown
* @return The configured manager
* @see ConfigFileReaderSupport#KEX_ALGORITHMS_CONFIG_PROP KEX_ALGORITHMS_CONFIG_PROP
* @see ConfigFileReaderSupport#DEFAULT_KEX_ALGORITHMS DEFAULT_KEX_ALGORITHMS
*/
public static M configureKeyExchanges(
M manager, PropertyResolver props, boolean lenient, Function> xformer, boolean ignoreUnsupported) {
Objects.requireNonNull(props, "No properties to configure");
return configureKeyExchanges(manager,
props.getStringProperty(ConfigFileReaderSupport.KEX_ALGORITHMS_CONFIG_PROP, ConfigFileReaderSupport.DEFAULT_KEX_ALGORITHMS),
lenient, xformer, ignoreUnsupported);
}
public static M configureKeyExchanges(
M manager, String value, boolean lenient, Function> xformer, boolean ignoreUnsupported) {
Objects.requireNonNull(manager, "No manager to configure");
Objects.requireNonNull(xformer, "No DHFactory transformer");
BuiltinDHFactories.ParseResult result = BuiltinDHFactories.parseDHFactoriesList(value);
Collection unsupported = result.getUnsupportedFactories();
ValidateUtils.checkTrue(lenient || GenericUtils.isEmpty(unsupported), "Unsupported KEX(s) (%s) in %s", unsupported, value);
List> factories =
NamedFactory.setUpTransformedFactories(ignoreUnsupported, result.getParsedFactories(), xformer);
manager.setKeyExchangeFactories(ValidateUtils.checkNotNullAndNotEmpty(factories, "No known/supported KEXS(s): %s", value));
return manager;
}
/**
* Configure the factory manager using one of the known {@link CompressionConfigValue}s.
*
* @param The generic factory manager
* @param manager The {@link AbstractFactoryManager} to configure
* @param props The configuration {@link Properties}
* @param lenient If {@code true} and an unknown value is provided then
* it is ignored
* @param ignoreUnsupported If {@code false} then check if the compression
* is currently supported before setting it
* @return The configured manager - Note: if the result of filtering due
* to lenient mode or ignored unsupported value is empty then no factories are set
*/
public static M configureCompression(
M manager, PropertyResolver props, boolean lenient, boolean ignoreUnsupported) {
Objects.requireNonNull(manager, "No manager to configure");
Objects.requireNonNull(props, "No properties to configure");
String value = props.getStringProperty(ConfigFileReaderSupport.COMPRESSION_PROP, ConfigFileReaderSupport.DEFAULT_COMPRESSION);
CompressionFactory factory = CompressionConfigValue.fromName(value);
ValidateUtils.checkTrue(lenient || (factory != null), "Unsupported compression value: %s", value);
if ((factory != null) && factory.isSupported()) {
manager.setCompressionFactories(Collections.singletonList(factory));
}
return manager;
}
// accepts BOTH CompressionConfigValue(s) and/or BuiltinCompressions - including extensions
public static M configureCompression(M manager, String value, boolean lenient, boolean ignoreUnsupported) {
Objects.requireNonNull(manager, "No manager to configure");
CompressionFactory factory = CompressionConfigValue.fromName(value);
if (factory != null) {
// SSH can work without compression
if (ignoreUnsupported || factory.isSupported()) {
manager.setCompressionFactories(Collections.singletonList(factory));
}
} else {
BuiltinCompressions.ParseResult result = BuiltinCompressions.parseCompressionsList(value);
Collection unsupported = result.getUnsupportedFactories();
ValidateUtils.checkTrue(lenient || GenericUtils.isEmpty(unsupported), "Unsupported compressions(s) (%s) in %s", unsupported, value);
List> factories =
BuiltinFactory.setUpFactories(ignoreUnsupported, result.getParsedFactories());
// SSH can work without compression
if (GenericUtils.size(factories) > 0) {
manager.setCompressionFactories(factories);
}
}
return manager;
}
}