commit 90ff9b555c9d043d8f4392e08ee6a5e5dcdc9f68 Author: Karsten Loesing karsten.loesing@gmx.net Date: Thu Apr 26 16:14:58 2012 +0200

Add code to verify consensuses (#2768). --- task-2768/VerifyDescriptors.java | 306 ++++++++++++++++++++++++++++++++ task-2768/VerifyServerDescriptors.java | 145 --------------- task-2768/run.sh | 2 +- 3 files changed, 307 insertions(+), 146 deletions(-)

diff --git a/task-2768/VerifyDescriptors.java b/task-2768/VerifyDescriptors.java new file mode 100644 index 0000000..b784cdd --- /dev/null +++ b/task-2768/VerifyDescriptors.java @@ -0,0 +1,306 @@ +/* Copyright 2012 The Tor Project + * See LICENSE for licensing information */ +import java.io.ByteArrayOutputStream; +import java.io.File; +import java.io.StringReader; +import java.security.Security; +import java.security.interfaces.RSAPublicKey; +import java.util.HashMap; +import java.util.Iterator; +import java.util.Map; + +import org.apache.commons.codec.binary.Base64; +import org.apache.commons.codec.binary.Hex; +import org.bouncycastle.asn1.ASN1OutputStream; +import org.bouncycastle.crypto.digests.SHA1Digest; +import org.bouncycastle.crypto.encodings.PKCS1Encoding; +import org.bouncycastle.crypto.engines.RSAEngine; +import org.bouncycastle.crypto.params.RSAKeyParameters; +import org.bouncycastle.jce.provider.BouncyCastleProvider; +import org.bouncycastle.openssl.PEMReader; +import org.torproject.descriptor.Descriptor; +import org.torproject.descriptor.DescriptorFile; +import org.torproject.descriptor.DescriptorReader; +import org.torproject.descriptor.DescriptorSourceFactory; +import org.torproject.descriptor.DirectoryKeyCertificate; +import org.torproject.descriptor.DirectorySignature; +import org.torproject.descriptor.RelayNetworkStatusConsensus; +import org.torproject.descriptor.ServerDescriptor; + +/* + * Verify server descriptors using the contained signing key. Verify that + * 1) a contained fingerprint is actually a hash of the signing key and + * 2) a router signature was created using the signing key. + * + * Verify consensuses using the separate certs. Verify that + * 1) the fingerprint in a cert is actually a hash of the identity key, + * 2) a cert was signed using the identity key, + * 3) a consensus was signed using the signing key from the cert. + * + * Usage: + * - Put certs in in/certs/, consensuses in in/consensuses/, and server + * descriptors in in/server-descriptors/. + * - Clone metrics-lib, run `ant jar`, and copy descriptor.jar to this + * directory. + * - Download Apache Commons Codec and Compress jar files + * commons-codec-1.4.jar and commons-compress-1.3.jar and put them in + * this directory. + * - Download BouncyCastle 1.47 jar files bcprov-jdk15on-147.jar and + * bcpkix-jdk15on-147.jar and put them in this directory. + * - Compile and run this class: ./run.sh. + */ +public class VerifyDescriptors { + public static void main(String[] args) throws Exception { + System.out.println("Verifying consensuses..."); + if (Security.getProvider("BC") == null) { + Security.addProvider(new BouncyCastleProvider()); + } + verifyServerDescriptors(); + verifyConsensuses(); + } + + private static void verifyServerDescriptors() throws Exception { + File serverDescriptorDirectory = new File("in/server-descriptors"); + if (!serverDescriptorDirectory.exists()) { + return; + } + DescriptorReader descriptorReader = DescriptorSourceFactory + .createDescriptorReader(); + descriptorReader.addDirectory(serverDescriptorDirectory); + Iterator<DescriptorFile> descriptorFiles = + descriptorReader.readDescriptors(); + int processedDescriptors = 0, verifiedDescriptors = 0; + while (descriptorFiles.hasNext()) { + DescriptorFile descriptorFile = descriptorFiles.next(); + if (descriptorFile.getException() != null) { + System.err.println("Could not read/parse descriptor file " + + descriptorFile.getFileName() + ": " + + descriptorFile.getException().getMessage()); + continue; + } + if (descriptorFile.getDescriptors() == null) { + continue; + } + for (Descriptor descriptor : descriptorFile.getDescriptors()) { + if (!(descriptor instanceof ServerDescriptor)) { + continue; + } + ServerDescriptor serverDescriptor = (ServerDescriptor) descriptor; + boolean isVerified = true; + + /* Verify that the contained fingerprint is a hash of the signing + * key. */ + String signingKeyHashString = determineKeyHash( + serverDescriptor.getSigningKey()); + String fingerprintString = + serverDescriptor.getFingerprint().toLowerCase(); + if (!signingKeyHashString.equals(fingerprintString)) { + System.out.println("In " + descriptorFile.getFile() + + ", server descriptor, the calculated signing key hash " + + " does not match the contained fingerprint!"); + isVerified = false; + } + + /* Verify that the router signature was created using the signing + * key. */ + if (!verifySignature(serverDescriptor.getServerDescriptorDigest(), + serverDescriptor.getRouterSignature(), + serverDescriptor.getSigningKey())) { + System.out.println("In " + descriptorFile.getFile() + + ", the decrypted signature does not match the descriptor " + + "digest!"); + isVerified = false; + } + + processedDescriptors++; + if (isVerified) { + verifiedDescriptors++; + } + } + } + System.out.println("Verified " + verifiedDescriptors + "/" + + processedDescriptors + " server descriptors."); + } + + private static void verifyConsensuses() throws Exception { + File certsDirectory = new File("in/certs"); + File consensusDirectory = new File("in/consensuses"); + if (!certsDirectory.exists() || !consensusDirectory.exists()) { + return; + } + Map<String, String> signingKeys = new HashMap<String, String>(); + + DescriptorReader certsReader = DescriptorSourceFactory + .createDescriptorReader(); + certsReader.addDirectory(certsDirectory); + Iterator<DescriptorFile> descriptorFiles = + certsReader.readDescriptors(); + int processedCerts = 0, verifiedCerts = 0; + while (descriptorFiles.hasNext()) { + DescriptorFile descriptorFile = descriptorFiles.next(); + if (descriptorFile.getException() != null) { + System.err.println("Could not read/parse descriptor file " + + descriptorFile.getFileName() + ": " + + descriptorFile.getException().getMessage()); + continue; + } + if (descriptorFile.getDescriptors() == null) { + continue; + } + for (Descriptor descriptor : descriptorFile.getDescriptors()) { + if (!(descriptor instanceof DirectoryKeyCertificate)) { + continue; + } + DirectoryKeyCertificate cert = + (DirectoryKeyCertificate) descriptor; + boolean isVerified = true; + + /* Verify that the contained fingerprint is a hash of the signing + * key. */ + String dirIdentityKeyHashString = determineKeyHash( + cert.getDirIdentityKey()); + String fingerprintString = cert.getFingerprint().toLowerCase(); + if (!dirIdentityKeyHashString.equals(fingerprintString)) { + System.out.println("In " + descriptorFile.getFile() + + ", the calculated directory identity key hash " + + dirIdentityKeyHashString + + " does not match the contained fingerprint " + + fingerprintString + "!"); + isVerified = false; + } + + /* Verify that the router signature was created using the signing + * key. */ + if (!verifySignature(cert.getCertificateDigest(), + cert.getDirKeyCertification(), cert.getDirIdentityKey())) { + System.out.println("In " + descriptorFile.getFile() + + ", the decrypted directory key certification does not " + + "match the certificate digest!"); + isVerified = false; + } + + /* Determine the signing key digest and remember the signing key + * to verify consensus signatures. */ + String dirSigningKeyString = cert.getDirSigningKey(); + PEMReader pemReader2 = new PEMReader(new StringReader( + dirSigningKeyString)); + RSAPublicKey dirSigningKey = + (RSAPublicKey) pemReader2.readObject(); + ByteArrayOutputStream baos2 = new ByteArrayOutputStream(); + new ASN1OutputStream(baos2).writeObject( + new org.bouncycastle.asn1.pkcs.RSAPublicKey( + dirSigningKey.getModulus(), + dirSigningKey.getPublicExponent()).toASN1Primitive()); + byte[] pkcs2 = baos2.toByteArray(); + byte[] dirSigningKeyHashBytes = new byte[20]; + SHA1Digest sha1_2 = new SHA1Digest(); + sha1_2.update(pkcs2, 0, pkcs2.length); + sha1_2.doFinal(dirSigningKeyHashBytes, 0); + String dirSigningKeyHashString = Hex.encodeHexString( + dirSigningKeyHashBytes).toUpperCase(); + signingKeys.put(dirSigningKeyHashString, cert.getDirSigningKey()); + + processedCerts++; + if (isVerified) { + verifiedCerts++; + } + } + } + System.out.println("Verified " + verifiedCerts + "/" + + processedCerts + " certs."); + + DescriptorReader consensusReader = DescriptorSourceFactory + .createDescriptorReader(); + consensusReader.addDirectory(consensusDirectory); + Iterator<DescriptorFile> consensusFiles = + consensusReader.readDescriptors(); + int processedConsensuses = 0, verifiedConsensuses = 0; + while (consensusFiles.hasNext()) { + DescriptorFile consensusFile = consensusFiles.next(); + if (consensusFile.getException() != null) { + System.err.println("Could not read/parse descriptor file " + + consensusFile.getFileName() + ": " + + consensusFile.getException().getMessage()); + continue; + } + if (consensusFile.getDescriptors() == null) { + continue; + } + for (Descriptor descriptor : consensusFile.getDescriptors()) { + if (!(descriptor instanceof RelayNetworkStatusConsensus)) { + continue; + } + RelayNetworkStatusConsensus consensus = + (RelayNetworkStatusConsensus) descriptor; + boolean isVerified = true; + + /* Verify all signatures using the corresponding certificates. */ + if (consensus.getDirectorySignatures().isEmpty()) { + System.out.println(consensusFile.getFile() + + " does not contain any signatures."); + continue; + } + for (DirectorySignature signature : + consensus.getDirectorySignatures().values()) { + String signingKeyDigest = signature.getSigningKeyDigest(); + if (!signingKeys.containsKey(signingKeyDigest)) { + System.out.println("Cannot find signing key with digest " + + signingKeyDigest + "!"); + } + if (!verifySignature(consensus.getConsensusDigest(), + signature.getSignature(), + signingKeys.get(signingKeyDigest))) { + System.out.println("In " + consensusFile.getFile() + + ", the decrypted signature digest does not match the " + + "consensus digest!"); + isVerified = false; + } + } + processedConsensuses++; + if (isVerified) { + verifiedConsensuses++; + } + } + } + System.out.println("Verified " + verifiedConsensuses + "/" + + processedConsensuses + " consensuses."); + } + + private static String determineKeyHash(String key) throws Exception { + PEMReader pemReader = new PEMReader(new StringReader(key)); + RSAPublicKey dirIdentityKey = (RSAPublicKey) pemReader.readObject(); + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + new ASN1OutputStream(baos).writeObject( + new org.bouncycastle.asn1.pkcs.RSAPublicKey( + dirIdentityKey.getModulus(), + dirIdentityKey.getPublicExponent()).toASN1Primitive()); + byte[] pkcs = baos.toByteArray(); + byte[] dirIdentityKeyHashBytes = new byte[20]; + SHA1Digest sha1 = new SHA1Digest(); + sha1.update(pkcs, 0, pkcs.length); + sha1.doFinal(dirIdentityKeyHashBytes, 0); + String keyHash = Hex.encodeHexString(dirIdentityKeyHashBytes); + return keyHash; + } + + private static boolean verifySignature(String digest, String signature, + String signingKey) throws Exception { + byte[] signatureBytes = Base64.decodeBase64(signature.substring( + 0 + "-----BEGIN SIGNATURE-----\n".length(), + signature.length() - "-----END SIGNATURE-----\n".length()). + replaceAll("\n", "")); + RSAPublicKey rsaSigningKey = (RSAPublicKey) new PEMReader( + new StringReader(signingKey)).readObject(); + RSAKeyParameters rsakp = new RSAKeyParameters(false, + rsaSigningKey.getModulus(), + rsaSigningKey.getPublicExponent()); + PKCS1Encoding pe = new PKCS1Encoding(new RSAEngine()); + pe.init(false, rsakp); + byte[] decryptedSignatureDigest = pe.processBlock( + signatureBytes, 0, signatureBytes.length); + String decryptedSignatureDigestString = + Hex.encodeHexString(decryptedSignatureDigest); + return decryptedSignatureDigestString.equalsIgnoreCase(digest); + } +} + diff --git a/task-2768/VerifyServerDescriptors.java b/task-2768/VerifyServerDescriptors.java deleted file mode 100644 index e648d92..0000000 --- a/task-2768/VerifyServerDescriptors.java +++ /dev/null @@ -1,145 +0,0 @@ -/* Copyright 2012 The Tor Project - * See LICENSE for licensing information */ -import java.io.ByteArrayOutputStream; -import java.io.File; -import java.io.StringReader; -import java.security.Security; -import java.security.interfaces.RSAPublicKey; -import java.util.Iterator; - -import org.apache.commons.codec.binary.Base64; -import org.apache.commons.codec.binary.Hex; -import org.bouncycastle.asn1.ASN1OutputStream; -import org.bouncycastle.crypto.digests.SHA1Digest; -import org.bouncycastle.crypto.encodings.PKCS1Encoding; -import org.bouncycastle.crypto.engines.RSAEngine; -import org.bouncycastle.crypto.params.RSAKeyParameters; -import org.bouncycastle.jce.provider.BouncyCastleProvider; -import org.bouncycastle.openssl.PEMReader; -import org.torproject.descriptor.Descriptor; -import org.torproject.descriptor.DescriptorFile; -import org.torproject.descriptor.DescriptorReader; -import org.torproject.descriptor.DescriptorSourceFactory; -import org.torproject.descriptor.ServerDescriptor; - -/* - * Verify server descriptors using the contained signing key. Verify that - * 1) the contained fingerprint is actually a hash of the signing key and - * 2) the router signature was created using the signing key. - * - * Usage: - * - Extract server descriptors to in/. - * - Clone metrics-lib, run `ant jar`, and copy descriptor.jar to this - * directory. - * - Download Apache Commons Codec and Compress jar files - * commons-codec-1.4.jar and commons-compress-1.3.jar and put them in - * this directory. - * - Download BouncyCastle 1.47 jar files bcprov-jdk15on-147.jar and - * bcpkix-jdk15on-147.jar and put them in this directory. - * - Compile and run this class: ./run.sh. - */ -public class VerifyServerDescriptors { - public static void main(String[] args) throws Exception { - System.out.println("Verifying descriptors..."); - if (Security.getProvider("BC") == null) { - Security.addProvider(new BouncyCastleProvider()); - } - File inputDirectory = new File("in/"); - DescriptorReader reader = DescriptorSourceFactory - .createDescriptorReader(); - reader.addDirectory(inputDirectory); - Iterator<DescriptorFile> descriptorFiles = reader.readDescriptors(); - int processedDescriptors = 0, verifiedDescriptors = 0; - while (descriptorFiles.hasNext()) { - DescriptorFile descriptorFile = descriptorFiles.next(); - if (descriptorFile.getException() != null) { - System.err.println("Could not read/parse descriptor file " - + descriptorFile.getFileName() + ": " - + descriptorFile.getException().getMessage()); - continue; - } - if (descriptorFile.getDescriptors() == null) { - continue; - } - for (Descriptor descriptor : descriptorFile.getDescriptors()) { - if (!(descriptor instanceof ServerDescriptor)) { - continue; - } - ServerDescriptor serverDescriptor = (ServerDescriptor) descriptor; - boolean isVerified = true; - - /* Verify that the contained fingerprint is a hash of the signing - * key. */ - String signingKeyString = serverDescriptor.getSigningKey(); - String fingerprintString = - serverDescriptor.getFingerprint().toLowerCase(); - PEMReader pemReader = new PEMReader(new StringReader( - signingKeyString)); - RSAPublicKey signingKey = (RSAPublicKey) pemReader.readObject(); - - ByteArrayOutputStream baos = new ByteArrayOutputStream(); - new ASN1OutputStream(baos).writeObject( - new org.bouncycastle.asn1.pkcs.RSAPublicKey( - signingKey.getModulus(), - signingKey.getPublicExponent()).toASN1Primitive()); - byte[] pkcs = baos.toByteArray(); - byte[] signingKeyHashBytes = new byte[20]; - SHA1Digest sha1 = new SHA1Digest(); - sha1.update(pkcs, 0, pkcs.length); - sha1.doFinal(signingKeyHashBytes, 0); - String signingKeyHashString = Hex.encodeHexString( - signingKeyHashBytes); - if (!signingKeyHashString.equals(fingerprintString)) { - System.out.println("In " + descriptorFile.getFile() - + ", server descriptor " - + serverDescriptor.getServerDescriptorDigest() - + ", the calculated signing key hash " - + signingKeyHashString - + " does not match the contained fingerprint " - + fingerprintString + "!"); - isVerified = false; - } - - /* Verify that the router signature was created using the signing - * key. */ - String serverDescriptorDigestString = serverDescriptor - .getServerDescriptorDigest().toLowerCase(); - String routerSignatureString = serverDescriptor - .getRouterSignature(); - byte[] routerSignature = Base64 - .decodeBase64(routerSignatureString.substring( - 0 + "-----BEGIN SIGNATURE-----\n".length(), - routerSignatureString.length() - - "-----END SIGNATURE-----\n".length()).replaceAll( - "\n", "")); - RSAKeyParameters rsakp = new RSAKeyParameters(false, - signingKey.getModulus(), signingKey.getPublicExponent()); - PKCS1Encoding pe = new PKCS1Encoding(new RSAEngine()); - pe.init(false, rsakp); - byte[] decryptedSignature = pe.processBlock(routerSignature, 0, - routerSignature.length); - String decryptedSignatureString = - Hex.encodeHexString(decryptedSignature); - if (!decryptedSignatureString.equals( - serverDescriptorDigestString)) { - System.out.println("In " + descriptorFile.getFile() - + ", server descriptor " - + serverDescriptor.getServerDescriptorDigest() - + ", the decrypted signature " - + decryptedSignatureString - + " does not match the descriptor digest " - + serverDescriptorDigestString + "!"); - isVerified = false; - } - - processedDescriptors++; - if (isVerified) { - verifiedDescriptors++; - } - } - } - System.out.println("Verified " + verifiedDescriptors + "/" - + processedDescriptors + " server descriptors."); - } -} - diff --git a/task-2768/run.sh b/task-2768/run.sh index ed5fcc4..658ed6a 100755 --- a/task-2768/run.sh +++ b/task-2768/run.sh @@ -1,3 +1,3 @@ #!/bin/bash -javac -cp descriptor.jar:commons-codec-1.4.jar:commons-compress-1.3.jar:bcprov-jdk15on-147.jar:bcpkix-jdk15on-147.jar VerifyServerDescriptors.java && java -cp descriptor.jar:commons-codec-1.4.jar:commons-compress-1.3.jar:bcprov-jdk15on-147.jar:bcpkix-jdk15on-147.jar:. VerifyServerDescriptors +javac -cp descriptor.jar:commons-codec-1.4.jar:commons-compress-1.3.jar:bcprov-jdk15on-147.jar:bcpkix-jdk15on-147.jar VerifyDescriptors.java && java -cp descriptor.jar:commons-codec-1.4.jar:commons-compress-1.3.jar:bcprov-jdk15on-147.jar:bcpkix-jdk15on-147.jar:. VerifyDescriptors