Remove advanced preferences, move compression as menu item in encrypt activites, select hash and encryption algo based on hardcoded preferred lists

19 files changed, 134 insertions, 484 deletions

diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java
index 574f16c27..30d855a74 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java
@@ -64,19 +64,12 @@ public final class Constants {
     }
 
     public static final class Pref {
-        public static final String DEFAULT_ENCRYPTION_ALGORITHM = "defaultEncryptionAlgorithm";
-        public static final String DEFAULT_HASH_ALGORITHM = "defaultHashAlgorithm";
-        public static final String DEFAULT_ASCII_ARMOR = "defaultAsciiArmor";
-        public static final String DEFAULT_MESSAGE_COMPRESSION = "defaultMessageCompression";
-        public static final String DEFAULT_FILE_COMPRESSION = "defaultFileCompression";
         public static final String PASSPHRASE_CACHE_TTL = "passphraseCacheTtl";
         public static final String PASSPHRASE_CACHE_SUBS = "passphraseCacheSubs";
         public static final String LANGUAGE = "language";
         public static final String KEY_SERVERS = "keyServers";
         public static final String PREF_DEFAULT_VERSION = "keyServersDefaultVersion";
-        public static final String WRITE_VERSION_HEADER = "writeVersionHeader";
         public static final String FIRST_TIME = "firstTime";
-        public static final String SHOW_ADVANCED_TABS = "showAdvancedTabs";
         public static final String CACHED_CONSOLIDATE = "cachedConsolidate";
         public static final String SEARCH_KEYSERVER = "search_keyserver_pref";
         public static final String SEARCH_KEYBASE = "search_keybase_pref";
@@ -86,7 +79,7 @@ public final class Constants {
 
     public static final class Defaults {
         public static final String KEY_SERVERS = "hkps://hkps.pool.sks-keyservers.net, hkps://pgp.mit.edu";
-        public static final int PREF_VERSION = 5;
+        public static final int PREF_VERSION = 4;
     }
 
     public static final class key {
@@ -94,11 +87,4 @@ public final class Constants {
         public static final int symmetric = -1;
     }
 
-    public static interface OpenKeychainSymmetricKeyAlgorithmTags extends SymmetricKeyAlgorithmTags {
-        public static final int USE_PREFERRED = -1;
-    }
-
-    public static interface OpenKeychainHashAlgorithmTags extends HashAlgorithmTags {
-        public static final int USE_PREFERRED = -1;
-    }
 }
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/ImportExportOperation.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/ImportExportOperation.java
index 8f10377cd..20dba95e9 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/ImportExportOperation.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/ImportExportOperation.java
@@ -505,10 +505,6 @@ public class ImportExportOperation extends BaseOperation {
                 // Create an output stream
                 try {
                     arOutStream = new ArmoredOutputStream(outStream);
-                    String version = PgpHelper.getVersionForHeader(mContext);
-                    if (version != null) {
-                        arOutStream.setHeader("Version", version);
-                    }
 
                     log.add(LogType.MSG_EXPORT_PUBLIC, 1, KeyFormattingUtils.beautifyKeyId(keyId));
 
@@ -533,10 +529,6 @@ public class ImportExportOperation extends BaseOperation {
                 if (exportSecret && cursor.getInt(3) > 0) {
                     try {
                         arOutStream = new ArmoredOutputStream(outStream);
-                        String version = PgpHelper.getVersionForHeader(mContext);
-                        if (version != null) {
-                            arOutStream.setHeader("Version", version);
-                        }
 
                         // export secret key part
                         log.add(LogType.MSG_EXPORT_SECRET, 2, KeyFormattingUtils.beautifyKeyId(keyId));
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/CanonicalizedSecretKey.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/CanonicalizedSecretKey.java
index 0fab4c747..9c74cf9a8 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/CanonicalizedSecretKey.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/CanonicalizedSecretKey.java
@@ -177,52 +177,20 @@ public class CanonicalizedSecretKey extends CanonicalizedPublicKey {
     }
 
     /**
-     * Returns a list of all supported hash algorithms. This list is currently hardcoded to return
-     * a limited set of algorithms supported by Yubikeys.
-     *
-     * TODO: look into preferred algos of this key?
+     * Returns a list of all supported hash algorithms.
      */
     public LinkedList<Integer> getSupportedHashAlgorithms() {
         LinkedList<Integer> supported = new LinkedList<>();
 
-        if (mPrivateKeyState == PRIVATE_KEY_STATE_DIVERT_TO_CARD) {
-            // No support for MD5
-            supported.add(HashAlgorithmTags.RIPEMD160);
-            // don't allow SHA1
-            supported.add(HashAlgorithmTags.SHA224);
-            supported.add(HashAlgorithmTags.SHA384);
-            supported.add(HashAlgorithmTags.SHA512);
-            supported.add(HashAlgorithmTags.SHA256); // preferred is latest
-        } else {
-            // NOTE: List of hash algorithms OpenKeychain wants to support!
-
-            // don't allow MD5
-            supported.add(HashAlgorithmTags.RIPEMD160);
-            // don't allow SHA1
-            supported.add(HashAlgorithmTags.SHA224);
-            supported.add(HashAlgorithmTags.SHA384);
-            supported.add(HashAlgorithmTags.SHA512);
-            supported.add(HashAlgorithmTags.SHA256); // preferred is latest
-            // some application don't support SHA512, thus preferred is SHA-256 (Mailvelope?)
+        // TODO: intersection between preferred hash algos of this key and PgpConstants.PREFERRED_HASH_ALGORITHMS
+        // choose best algo
+        for (int currentInt : PgpConstants.PREFERRED_HASH_ALGORITHMS) {
+            supported.add(currentInt);
         }
 
         return supported;
     }
 
-    /**
-     * TODO: look into preferred algos of this key?
-     */
-    public static LinkedList<Integer> getSupportedEncryptionAlgorithms() {
-        LinkedList<Integer> supported = new LinkedList<>();
-
-        supported.add(SymmetricKeyAlgorithmTags.TWOFISH);
-        supported.add(SymmetricKeyAlgorithmTags.AES_128);
-        supported.add(SymmetricKeyAlgorithmTags.AES_192);
-        supported.add(SymmetricKeyAlgorithmTags.AES_256); // preferred is latest
-
-        return supported;
-    }
-
     private PGPContentSignerBuilder getContentSignerBuilder(int hashAlgo, byte[] nfcSignedHash,
                                                             Date nfcCreationTimestamp) {
         if (mPrivateKeyState == PRIVATE_KEY_STATE_DIVERT_TO_CARD) {
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpHelper.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpHelper.java
index 12de2f637..d8b86a18c 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpHelper.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpHelper.java
@@ -47,26 +47,6 @@ public class PgpHelper {
             ".*?(-----BEGIN PGP PUBLIC KEY BLOCK-----.*?-----END PGP PUBLIC KEY BLOCK-----).*",
             Pattern.DOTALL);
 
-    public static String getVersion(Context context) {
-        String version;
-        try {
-            PackageInfo pi = context.getPackageManager().getPackageInfo(Constants.PACKAGE_NAME, 0);
-            version = pi.versionName;
-            return version;
-        } catch (NameNotFoundException e) {
-            Log.e(Constants.TAG, "Version could not be retrieved!", e);
-            return "0.0";
-        }
-    }
-
-    public static String getVersionForHeader(Context context) {
-        if(Preferences.getPreferences(context).getWriteVersionHeader()){
-            return "OpenKeychain v" + getVersion(context);
-        } else {
-            return null;
-        }
-    }
-
     /**
      * Deletes file securely by overwriting it with random data before deleting it.
      * <p/>
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java
index a54fa189a..ac9acd41b 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java
@@ -18,9 +18,7 @@
 
 package org.sufficientlysecure.keychain.pgp;
 
-import org.spongycastle.bcpg.CompressionAlgorithmTags;
 import org.spongycastle.bcpg.HashAlgorithmTags;
-import org.spongycastle.bcpg.SymmetricKeyAlgorithmTags;
 import org.spongycastle.bcpg.sig.Features;
 import org.spongycastle.bcpg.sig.KeyFlags;
 import org.spongycastle.jce.spec.ElGamalParameterSpec;
@@ -90,49 +88,6 @@ public class PgpKeyOperation {
     private Stack<Progressable> mProgress;
     private AtomicBoolean mCancelled;
 
-    // most preferred is first
-    private static final int[] PREFERRED_SYMMETRIC_ALGORITHMS = new int[]{
-            SymmetricKeyAlgorithmTags.AES_256,
-            SymmetricKeyAlgorithmTags.AES_192,
-            SymmetricKeyAlgorithmTags.AES_128,
-            SymmetricKeyAlgorithmTags.TWOFISH
-    };
-    private static final int[] PREFERRED_HASH_ALGORITHMS = new int[]{
-            HashAlgorithmTags.SHA512,
-            HashAlgorithmTags.SHA384,
-            HashAlgorithmTags.SHA256,
-            HashAlgorithmTags.SHA224,
-            HashAlgorithmTags.RIPEMD160
-    };
-    private static final int[] PREFERRED_COMPRESSION_ALGORITHMS = new int[]{
-            CompressionAlgorithmTags.ZLIB,
-            CompressionAlgorithmTags.BZIP2,
-            CompressionAlgorithmTags.ZIP
-    };
-
-    /*
-     * Note: s2kcount is a number between 0 and 0xff that controls the
-     * number of times to iterate the password hash before use. More
-     * iterations are useful against offline attacks, as it takes more
-     * time to check each password. The actual number of iterations is
-     * rather complex, and also depends on the hash function in use.
-     * Refer to Section 3.7.1.3 in rfc4880.txt. Bigger numbers give
-     * you more iterations.  As a rough rule of thumb, when using
-     * SHA256 as the hashing function, 0x10 gives you about 64
-     * iterations, 0x20 about 128, 0x30 about 256 and so on till 0xf0,
-     * or about 1 million iterations. The maximum you can go to is
-     * 0xff, or about 2 million iterations.
-     * from http://kbsriram.com/2013/01/generating-rsa-keys-with-bouncycastle.html
-     *
-     * Bouncy Castle default: 0x60
-     * kbsriram proposes 0xc0
-     * we use 0x90, a good trade-off between usability and security against offline attacks
-     */
-    private static final int SECRET_KEY_ENCRYPTOR_S2K_COUNT = 0x90;
-    private static final int SECRET_KEY_ENCRYPTOR_HASH_ALGO = HashAlgorithmTags.SHA256;
-    private static final int SECRET_KEY_ENCRYPTOR_SYMMETRIC_ALGO = SymmetricKeyAlgorithmTags.AES_256;
-    private static final int SECRET_KEY_SIGNATURE_HASH_ALGO = HashAlgorithmTags.SHA256;
-
     public PgpKeyOperation(Progressable progress) {
         super();
         if (progress != null) {
@@ -346,14 +301,14 @@ public class PgpKeyOperation {
 
             // Build key encrypter and decrypter based on passphrase
             PGPDigestCalculator encryptorHashCalc = new JcaPGPDigestCalculatorProviderBuilder()
-                    .build().get(SECRET_KEY_ENCRYPTOR_HASH_ALGO);
+                    .build().get(PgpConstants.SECRET_KEY_ENCRYPTOR_HASH_ALGO);
             PBESecretKeyEncryptor keyEncryptor = new JcePBESecretKeyEncryptorBuilder(
-                    SECRET_KEY_ENCRYPTOR_SYMMETRIC_ALGO, encryptorHashCalc, SECRET_KEY_ENCRYPTOR_S2K_COUNT)
+                    PgpConstants.SECRET_KEY_ENCRYPTOR_SYMMETRIC_ALGO,
+                    encryptorHashCalc, PgpConstants.SECRET_KEY_ENCRYPTOR_S2K_COUNT)
                     .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build("".toCharArray());
 
-            // NOTE: only SHA1 is supported for key checksum calculations.
             PGPDigestCalculator sha1Calc = new JcaPGPDigestCalculatorProviderBuilder()
-                    .build().get(HashAlgorithmTags.SHA1);
+                    .build().get(PgpConstants.SECRET_KEY_SIGNATURE_CHECKSUM_HASH_ALGO);
             PGPSecretKey masterSecretKey = new PGPSecretKey(keyPair.getPrivateKey(), keyPair.getPublicKey(),
                     sha1Calc, true, keyEncryptor);
 
@@ -880,14 +835,14 @@ public class PgpKeyOperation {
                 PGPSecretKey sKey; {
                     // Build key encrypter and decrypter based on passphrase
                     PGPDigestCalculator encryptorHashCalc = new JcaPGPDigestCalculatorProviderBuilder()
-                            .build().get(SECRET_KEY_ENCRYPTOR_HASH_ALGO);
+                            .build().get(PgpConstants.SECRET_KEY_ENCRYPTOR_HASH_ALGO);
                     PBESecretKeyEncryptor keyEncryptor = new JcePBESecretKeyEncryptorBuilder(
-                            SECRET_KEY_ENCRYPTOR_SYMMETRIC_ALGO, encryptorHashCalc, SECRET_KEY_ENCRYPTOR_S2K_COUNT)
+                            PgpConstants.SECRET_KEY_ENCRYPTOR_SYMMETRIC_ALGO, encryptorHashCalc,
+                            PgpConstants.SECRET_KEY_ENCRYPTOR_S2K_COUNT)
                             .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(passphrase.toCharArray());
 
-                    // NOTE: only SHA1 is supported for key checksum calculations.
                     PGPDigestCalculator sha1Calc = new JcaPGPDigestCalculatorProviderBuilder()
-                            .build().get(HashAlgorithmTags.SHA1);
+                            .build().get(PgpConstants.SECRET_KEY_SIGNATURE_CHECKSUM_HASH_ALGO);
                     sKey = new PGPSecretKey(keyPair.getPrivateKey(), pKey, sha1Calc, false, keyEncryptor);
                 }
 
@@ -1026,7 +981,8 @@ public class PgpKeyOperation {
 
                 // add packet with EMPTY notation data (updates old one, but will be stripped later)
                 PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder(
-                        masterPrivateKey.getPublicKeyPacket().getAlgorithm(), SECRET_KEY_SIGNATURE_HASH_ALGO)
+                        masterPrivateKey.getPublicKeyPacket().getAlgorithm(),
+                        PgpConstants.SECRET_KEY_SIGNATURE_HASH_ALGO)
                         .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
                 PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder);
                 { // set subpackets
@@ -1052,7 +1008,8 @@ public class PgpKeyOperation {
 
             // add packet with "pin" notation data
             PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder(
-                    masterPrivateKey.getPublicKeyPacket().getAlgorithm(), SECRET_KEY_SIGNATURE_HASH_ALGO)
+                    masterPrivateKey.getPublicKeyPacket().getAlgorithm(),
+                    PgpConstants.SECRET_KEY_SIGNATURE_HASH_ALGO)
                     .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
             PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder);
             { // set subpackets
@@ -1099,12 +1056,13 @@ public class PgpKeyOperation {
             OperationLog log, int indent) throws PGPException {
 
         PGPDigestCalculator encryptorHashCalc = new JcaPGPDigestCalculatorProviderBuilder().build()
-                .get(SECRET_KEY_ENCRYPTOR_HASH_ALGO);
+                .get(PgpConstants.SECRET_KEY_ENCRYPTOR_HASH_ALGO);
         PBESecretKeyDecryptor keyDecryptor = new JcePBESecretKeyDecryptorBuilder().setProvider(
                 Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(passphrase.toCharArray());
         // Build key encryptor based on new passphrase
         PBESecretKeyEncryptor keyEncryptorNew = new JcePBESecretKeyEncryptorBuilder(
-                SECRET_KEY_ENCRYPTOR_SYMMETRIC_ALGO, encryptorHashCalc, SECRET_KEY_ENCRYPTOR_S2K_COUNT)
+                PgpConstants.SECRET_KEY_ENCRYPTOR_SYMMETRIC_ALGO, encryptorHashCalc,
+                PgpConstants.SECRET_KEY_ENCRYPTOR_S2K_COUNT)
                 .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(
                         newPassphrase.toCharArray());
 
@@ -1237,7 +1195,8 @@ public class PgpKeyOperation {
             int flags, long expiry)
             throws IOException, PGPException, SignatureException {
         PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder(
-                masterPrivateKey.getPublicKeyPacket().getAlgorithm(), SECRET_KEY_SIGNATURE_HASH_ALGO)
+                masterPrivateKey.getPublicKeyPacket().getAlgorithm(),
+                PgpConstants.SECRET_KEY_SIGNATURE_HASH_ALGO)
                 .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
         PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder);
 
@@ -1254,9 +1213,9 @@ public class PgpKeyOperation {
              * error than be ignored.
              */
             /* non-critical subpackets: */
-            hashedPacketsGen.setPreferredSymmetricAlgorithms(false, PREFERRED_SYMMETRIC_ALGORITHMS);
-            hashedPacketsGen.setPreferredHashAlgorithms(false, PREFERRED_HASH_ALGORITHMS);
-            hashedPacketsGen.setPreferredCompressionAlgorithms(false, PREFERRED_COMPRESSION_ALGORITHMS);
+            hashedPacketsGen.setPreferredSymmetricAlgorithms(false, PgpConstants.PREFERRED_SYMMETRIC_ALGORITHMS);
+            hashedPacketsGen.setPreferredHashAlgorithms(false, PgpConstants.PREFERRED_HASH_ALGORITHMS);
+            hashedPacketsGen.setPreferredCompressionAlgorithms(false, PgpConstants.PREFERRED_COMPRESSION_ALGORITHMS);
             hashedPacketsGen.setPrimaryUserID(false, primary);
 
             /* critical subpackets: we consider those important for a modern pgp implementation */
@@ -1280,7 +1239,8 @@ public class PgpKeyOperation {
             PGPUserAttributeSubpacketVector vector)
                 throws IOException, PGPException, SignatureException {
         PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder(
-                masterPrivateKey.getPublicKeyPacket().getAlgorithm(), SECRET_KEY_SIGNATURE_HASH_ALGO)
+                masterPrivateKey.getPublicKeyPacket().getAlgorithm(),
+                PgpConstants.SECRET_KEY_SIGNATURE_HASH_ALGO)
                 .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
         PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder);
 
@@ -1299,7 +1259,8 @@ public class PgpKeyOperation {
             PGPPrivateKey masterPrivateKey, PGPPublicKey pKey, String userId)
         throws IOException, PGPException, SignatureException {
         PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder(
-                masterPrivateKey.getPublicKeyPacket().getAlgorithm(), SECRET_KEY_SIGNATURE_HASH_ALGO)
+                masterPrivateKey.getPublicKeyPacket().getAlgorithm(),
+                PgpConstants.SECRET_KEY_SIGNATURE_HASH_ALGO)
                 .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
         PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder);
         PGPSignatureSubpacketGenerator subHashedPacketsGen = new PGPSignatureSubpacketGenerator();
@@ -1313,7 +1274,7 @@ public class PgpKeyOperation {
             PGPPublicKey masterPublicKey, PGPPrivateKey masterPrivateKey, PGPPublicKey pKey)
             throws IOException, PGPException, SignatureException {
         PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder(
-                masterPublicKey.getAlgorithm(), SECRET_KEY_SIGNATURE_HASH_ALGO)
+                masterPublicKey.getAlgorithm(), PgpConstants.SECRET_KEY_SIGNATURE_HASH_ALGO)
                 .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
         PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder);
         PGPSignatureSubpacketGenerator subHashedPacketsGen = new PGPSignatureSubpacketGenerator();
@@ -1357,7 +1318,7 @@ public class PgpKeyOperation {
             PGPSignatureSubpacketGenerator subHashedPacketsGen = new PGPSignatureSubpacketGenerator();
             subHashedPacketsGen.setSignatureCreationTime(false, creationTime);
             PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder(
-                    pKey.getAlgorithm(), SECRET_KEY_SIGNATURE_HASH_ALGO)
+                    pKey.getAlgorithm(), PgpConstants.SECRET_KEY_SIGNATURE_HASH_ALGO)
                     .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
             PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder);
             sGen.init(PGPSignature.PRIMARYKEY_BINDING, subPrivateKey);
@@ -1378,7 +1339,7 @@ public class PgpKeyOperation {
         }
 
         PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder(
-                masterPublicKey.getAlgorithm(), SECRET_KEY_SIGNATURE_HASH_ALGO)
+                masterPublicKey.getAlgorithm(), PgpConstants.SECRET_KEY_SIGNATURE_HASH_ALGO)
                 .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
         PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder);
         sGen.init(PGPSignature.SUBKEY_BINDING, masterPrivateKey);
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptInput.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptInput.java
index f22d107e4..1ed0a4720 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptInput.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptInput.java
@@ -12,10 +12,10 @@ public class PgpSignEncryptInput {
     protected int mCompressionId = CompressionAlgorithmTags.UNCOMPRESSED;
     protected long[] mEncryptionMasterKeyIds = null;
     protected String mSymmetricPassphrase = null;
-    protected int mSymmetricEncryptionAlgorithm = Constants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED;
+    protected int mSymmetricEncryptionAlgorithm = PgpConstants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED;
     protected long mSignatureMasterKeyId = Constants.key.none;
     protected Long mSignatureSubKeyId = null;
-    protected int mSignatureHashAlgorithm = Constants.OpenKeychainHashAlgorithmTags.USE_PREFERRED;
+    protected int mSignatureHashAlgorithm = PgpConstants.OpenKeychainHashAlgorithmTags.USE_PREFERRED;
     protected String mSignaturePassphrase = null;
     protected long mAdditionalEncryptId = Constants.key.none;
     protected byte[] mNfcSignedHash = null;
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptOperation.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptOperation.java
index d420ddb5a..7d0949c6c 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptOperation.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptOperation.java
@@ -208,9 +208,9 @@ public class PgpSignEncryptOperation extends BaseOperation {
             // Use preferred hash algo
             int requestedAlgorithm = input.getSignatureHashAlgorithm();
             LinkedList<Integer> supported = signingKey.getSupportedHashAlgorithms();
-            if (requestedAlgorithm == Constants.OpenKeychainHashAlgorithmTags.USE_PREFERRED) {
+            if (requestedAlgorithm == PgpConstants.OpenKeychainHashAlgorithmTags.USE_PREFERRED) {
                 // get most preferred
-                input.setSignatureHashAlgorithm(supported.getLast());
+                input.setSignatureHashAlgorithm(supported.getFirst());
             } else if (!supported.contains(requestedAlgorithm)) {
                 log.add(LogType.MSG_PSE_ERROR_HASH_ALGO, indent);
                 return new PgpSignEncryptResult(PgpSignEncryptResult.RESULT_ERROR, log);
@@ -224,9 +224,10 @@ public class PgpSignEncryptOperation extends BaseOperation {
 
             // Use preferred encryption algo
             int algo = input.getSymmetricEncryptionAlgorithm();
-            if (algo == Constants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED) {
+            if (algo == PgpConstants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED) {
                 // get most preferred
-                algo = CanonicalizedSecretKey.getSupportedEncryptionAlgorithms().getLast();
+                // TODO: get from recipients
+                algo = PgpConstants.PREFERRED_SYMMETRIC_ALGORITHMS[0];
             }
             // has Integrity packet enabled!
             JcePGPDataEncryptorBuilder encryptorBuilder =
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java
index d947ae053..6366e8536 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java
@@ -1372,8 +1372,7 @@ public class ProviderHelper {
         UncachedKeyRing keyRing = UncachedKeyRing.decodeFromData(data);
 
         ByteArrayOutputStream bos = new ByteArrayOutputStream();
-        String version = PgpHelper.getVersionForHeader(mContext);
-        keyRing.encodeArmored(bos, version);
+        keyRing.encodeArmored(bos, null);
         String armoredKey = bos.toString("UTF-8");
 
         Log.d(Constants.TAG, "armoredKey:" + armoredKey);
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/OpenPgpService.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/OpenPgpService.java
index 38f7aa685..03fa41984 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/OpenPgpService.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/OpenPgpService.java
@@ -36,8 +36,10 @@ import org.sufficientlysecure.keychain.Constants;
 import org.sufficientlysecure.keychain.operations.results.DecryptVerifyResult;
 import org.sufficientlysecure.keychain.operations.results.OperationResult.LogEntryParcel;
 import org.sufficientlysecure.keychain.operations.results.PgpSignEncryptResult;
+import org.sufficientlysecure.keychain.pgp.PgpConstants;
 import org.sufficientlysecure.keychain.pgp.PgpDecryptVerify;
 import org.sufficientlysecure.keychain.pgp.PgpHelper;
+import org.sufficientlysecure.keychain.pgp.PgpKeyOperation;
 import org.sufficientlysecure.keychain.pgp.PgpSignEncryptInput;
 import org.sufficientlysecure.keychain.pgp.PgpSignEncryptOperation;
 import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralException;
@@ -260,8 +262,8 @@ public class OpenPgpService extends RemoteService {
                     .setEnableAsciiArmorOutput(asciiArmor)
                     .setCleartextSignature(cleartextSign)
                     .setDetachedSignature(!cleartextSign)
-                    .setVersionHeader(PgpHelper.getVersionForHeader(this))
-                    .setSignatureHashAlgorithm(Preferences.getPreferences(this).getDefaultHashAlgorithm())
+                    .setVersionHeader(null)
+                    .setSignatureHashAlgorithm(PgpConstants.OpenKeychainHashAlgorithmTags.USE_PREFERRED)
                     .setSignatureMasterKeyId(accSettings.getKeyId())
                     .setNfcState(nfcSignedHash, nfcCreationDate);
 
@@ -358,9 +360,9 @@ public class OpenPgpService extends RemoteService {
 
             PgpSignEncryptInput pseInput = new PgpSignEncryptInput();
             pseInput.setEnableAsciiArmorOutput(asciiArmor)
-                    .setVersionHeader(PgpHelper.getVersionForHeader(this))
+                    .setVersionHeader(null)
                     .setCompressionId(CompressionAlgorithmTags.UNCOMPRESSED)
-                    .setSymmetricEncryptionAlgorithm(Preferences.getPreferences(this).getDefaultEncryptionAlgorithm())
+                    .setSymmetricEncryptionAlgorithm(PgpConstants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED)
                     .setEncryptionMasterKeyIds(keyIds)
                     .setFailOnMissingEncryptionKeyIds(true)
                     .setAdditionalEncryptId(accSettings.getKeyId()); // add acc key for encryption
@@ -376,7 +378,7 @@ public class OpenPgpService extends RemoteService {
                 }
 
                 // sign and encrypt
-                pseInput.setSignatureHashAlgorithm(Preferences.getPreferences(this).getDefaultHashAlgorithm())
+                pseInput.setSignatureHashAlgorithm(PgpConstants.OpenKeychainHashAlgorithmTags.USE_PREFERRED)
                         .setSignatureMasterKeyId(accSettings.getKeyId())
                         .setNfcState(nfcSignedHash, nfcCreationDate);
             }
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptActivityInterface.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptActivityInterface.java
index 54fe369a7..baf445293 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptActivityInterface.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptActivityInterface.java
@@ -28,6 +28,7 @@ public interface EncryptActivityInterface {
     }
 
     public boolean isUseArmor();
+    public boolean isUseCompression();
 
     public long getSignatureKey();
     public long[] getEncryptionKeys();
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptFilesActivity.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptFilesActivity.java
index fab6c19f9..ac12faa3d 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptFilesActivity.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptFilesActivity.java
@@ -25,11 +25,13 @@ import android.support.v4.app.Fragment;
 import android.view.Menu;
 import android.view.MenuItem;
 
+import org.spongycastle.bcpg.CompressionAlgorithmTags;
 import org.sufficientlysecure.keychain.Constants;
 import org.sufficientlysecure.keychain.R;
 import org.sufficientlysecure.keychain.api.OpenKeychainIntents;
 import org.sufficientlysecure.keychain.operations.results.SignEncryptResult;
 import org.sufficientlysecure.keychain.pgp.KeyRing;
+import org.sufficientlysecure.keychain.pgp.PgpConstants;
 import org.sufficientlysecure.keychain.pgp.SignEncryptParcel;
 import org.sufficientlysecure.keychain.ui.dialog.DeleteFileDialogFragment;
 import org.sufficientlysecure.keychain.ui.util.Notify;
@@ -66,6 +68,7 @@ public class EncryptFilesActivity extends EncryptActivity implements EncryptActi
     private long mSigningKeyId = Constants.key.none;
     private String mPassphrase = "";
     private boolean mUseArmor;
+    private boolean mUseCompression;
     private boolean mDeleteAfterEncrypt = false;
     private boolean mShareAfterEncrypt = false;
     private ArrayList<Uri> mInputUris;
@@ -82,6 +85,11 @@ public class EncryptFilesActivity extends EncryptActivity implements EncryptActi
     }
 
     @Override
+    public boolean isUseCompression() {
+        return mUseCompression;
+    }
+
+    @Override
     public long getSignatureKey() {
         return mSigningKeyId;
     }
@@ -196,12 +204,13 @@ public class EncryptFilesActivity extends EncryptActivity implements EncryptActi
         data.addInputUris(mInputUris);
         data.addOutputUris(mOutputUris);
 
-        data.setCompressionId(Preferences.getPreferences(this).getDefaultMessageCompression());
-        data.setSymmetricEncryptionAlgorithm(Preferences.getPreferences(this).getDefaultEncryptionAlgorithm());
-        data.setSignatureHashAlgorithm(Preferences.getPreferences(this).getDefaultHashAlgorithm());
-
-        // Always use armor for messages
-        data.setEnableAsciiArmorOutput(mUseArmor);
+        if (mUseCompression) {
+            data.setCompressionId(CompressionAlgorithmTags.ZLIB);
+        } else {
+            data.setCompressionId(CompressionAlgorithmTags.UNCOMPRESSED);
+        }
+        data.setSymmetricEncryptionAlgorithm(PgpConstants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED);
+        data.setSignatureHashAlgorithm(PgpConstants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED);
 
         if (isModeSymmetric()) {
             Log.d(Constants.TAG, "Symmetric encryption enabled!");
@@ -317,8 +326,6 @@ public class EncryptFilesActivity extends EncryptActivity implements EncryptActi
         // Handle intent actions
         handleActions(getIntent());
         updateModeFragment();
-
-        mUseArmor = Preferences.getPreferences(this).getDefaultAsciiArmor();
     }
 
     @Override
@@ -329,7 +336,6 @@ public class EncryptFilesActivity extends EncryptActivity implements EncryptActi
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.encrypt_file_activity, menu);
-        menu.findItem(R.id.check_use_armor).setChecked(mUseArmor);
         return super.onCreateOptionsMenu(menu);
     }
 
@@ -350,21 +356,30 @@ public class EncryptFilesActivity extends EncryptActivity implements EncryptActi
             item.setChecked(!item.isChecked());
         }
         switch (item.getItemId()) {
-            case R.id.check_use_symmetric:
+            case R.id.check_use_symmetric: {
                 mCurrentMode = item.isChecked() ? MODE_SYMMETRIC : MODE_ASYMMETRIC;
                 updateModeFragment();
                 notifyUpdate();
                 break;
-            case R.id.check_use_armor:
+            }
+            case R.id.check_use_armor: {
                 mUseArmor = item.isChecked();
                 notifyUpdate();
                 break;
-            case R.id.check_delete_after_encrypt:
+            }
+            case R.id.check_delete_after_encrypt: {
                 mDeleteAfterEncrypt = item.isChecked();
                 notifyUpdate();
                 break;
-            default:
+            }
+            case R.id.check_enable_compression: {
+                mUseCompression = item.isChecked();
+                notifyUpdate();
+                break;
+            }
+            default: {
                 return super.onOptionsItemSelected(item);
+            }
         }
         return true;
     }
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptTextActivity.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptTextActivity.java
index 05da7a3ba..9ec0bdd33 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptTextActivity.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/EncryptTextActivity.java
@@ -25,12 +25,14 @@ import android.support.v4.app.Fragment;
 import android.view.Menu;
 import android.view.MenuItem;
 
+import org.spongycastle.bcpg.CompressionAlgorithmTags;
 import org.sufficientlysecure.keychain.Constants;
 import org.sufficientlysecure.keychain.R;
 import org.sufficientlysecure.keychain.api.OpenKeychainIntents;
 import org.sufficientlysecure.keychain.compatibility.ClipboardReflection;
 import org.sufficientlysecure.keychain.operations.results.SignEncryptResult;
 import org.sufficientlysecure.keychain.pgp.KeyRing;
+import org.sufficientlysecure.keychain.pgp.PgpConstants;
 import org.sufficientlysecure.keychain.pgp.SignEncryptParcel;
 import org.sufficientlysecure.keychain.ui.util.Notify;
 import org.sufficientlysecure.keychain.util.Log;
@@ -70,6 +72,7 @@ public class EncryptTextActivity extends EncryptActivity implements EncryptActiv
     private ArrayList<Uri> mInputUris;
     private ArrayList<Uri> mOutputUris;
     private String mMessage = "";
+    private boolean mUseCompression;
 
     public boolean isModeSymmetric() {
         return MODE_SYMMETRIC == mCurrentMode;
@@ -81,6 +84,11 @@ public class EncryptTextActivity extends EncryptActivity implements EncryptActiv
     }
 
     @Override
+    public boolean isUseCompression() {
+        return mUseCompression;
+    }
+
+    @Override
     public long getSignatureKey() {
         return mSigningKeyId;
     }
@@ -189,9 +197,13 @@ public class EncryptTextActivity extends EncryptActivity implements EncryptActiv
         data.setBytes(mMessage.getBytes());
         data.setCleartextSignature(true);
 
-        data.setCompressionId(Preferences.getPreferences(this).getDefaultMessageCompression());
-        data.setSymmetricEncryptionAlgorithm(Preferences.getPreferences(this).getDefaultEncryptionAlgorithm());
-        data.setSignatureHashAlgorithm(Preferences.getPreferences(this).getDefaultHashAlgorithm());
+        if (mUseCompression) {
+            data.setCompressionId(CompressionAlgorithmTags.ZLIB);
+        } else {
+            data.setCompressionId(CompressionAlgorithmTags.UNCOMPRESSED);
+        }
+        data.setSymmetricEncryptionAlgorithm(PgpConstants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED);
+        data.setSignatureHashAlgorithm(PgpConstants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED);
 
         // Always use armor for messages
         data.setEnableAsciiArmorOutput(true);
@@ -330,13 +342,20 @@ public class EncryptTextActivity extends EncryptActivity implements EncryptActiv
             item.setChecked(!item.isChecked());
         }
         switch (item.getItemId()) {
-            case R.id.check_use_symmetric:
+            case R.id.check_use_symmetric: {
                 mCurrentMode = item.isChecked() ? MODE_SYMMETRIC : MODE_ASYMMETRIC;
                 updateModeFragment();
                 notifyUpdate();
                 break;
-            default:
+            }
+            case R.id.check_enable_compression: {
+                mUseCompression = item.isChecked();
+                notifyUpdate();
+                break;
+            }
+            default: {
                 return super.onOptionsItemSelected(item);
+            }
         }
         return true;
     }
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/SettingsActivity.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/SettingsActivity.java
index d82be2571..210960b65 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/SettingsActivity.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/SettingsActivity.java
@@ -91,12 +91,6 @@ public class SettingsActivity extends PreferenceActivity {
             initializePassphraseCacheTtl(
                     (IntegerListPreference) findPreference(Constants.Pref.PASSPHRASE_CACHE_TTL));
 
-            initializeEncryptionAlgorithm(
-                    (IntegerListPreference) findPreference(Constants.Pref.DEFAULT_ENCRYPTION_ALGORITHM));
-
-            initializeHashAlgorithm(
-                    (IntegerListPreference) findPreference(Constants.Pref.DEFAULT_HASH_ALGORITHM));
-
             int[] valueIds = new int[]{
                     CompressionAlgorithmTags.UNCOMPRESSED,
                     CompressionAlgorithmTags.ZIP,
@@ -113,20 +107,6 @@ public class SettingsActivity extends PreferenceActivity {
                 values[i] = "" + valueIds[i];
             }
 
-            initializeMessageCompression(
-                    (IntegerListPreference) findPreference(Constants.Pref.DEFAULT_MESSAGE_COMPRESSION),
-                    entries, values);
-
-            initializeFileCompression(
-                    (IntegerListPreference) findPreference(Constants.Pref.DEFAULT_FILE_COMPRESSION),
-                    entries, values);
-
-            initializeAsciiArmor(
-                    (CheckBoxPreference) findPreference(Constants.Pref.DEFAULT_ASCII_ARMOR));
-
-            initializeWriteVersionHeader(
-                    (CheckBoxPreference) findPreference(Constants.Pref.WRITE_VERSION_HEADER));
-
             initializeUseDefaultYubikeyPin(
                     (CheckBoxPreference) findPreference(Constants.Pref.USE_DEFAULT_YUBIKEY_PIN));
 
@@ -263,12 +243,6 @@ public class SettingsActivity extends PreferenceActivity {
             initializePassphraseCacheTtl(
                     (IntegerListPreference) findPreference(Constants.Pref.PASSPHRASE_CACHE_TTL));
 
-            initializeEncryptionAlgorithm(
-                    (IntegerListPreference) findPreference(Constants.Pref.DEFAULT_ENCRYPTION_ALGORITHM));
-
-            initializeHashAlgorithm(
-                    (IntegerListPreference) findPreference(Constants.Pref.DEFAULT_HASH_ALGORITHM));
-
             int[] valueIds = new int[]{
                     CompressionAlgorithmTags.UNCOMPRESSED,
                     CompressionAlgorithmTags.ZIP,
@@ -288,20 +262,6 @@ public class SettingsActivity extends PreferenceActivity {
                 values[i] = "" + valueIds[i];
             }
 
-            initializeMessageCompression(
-                    (IntegerListPreference) findPreference(Constants.Pref.DEFAULT_MESSAGE_COMPRESSION),
-                    entries, values);
-
-            initializeFileCompression(
-                    (IntegerListPreference) findPreference(Constants.Pref.DEFAULT_FILE_COMPRESSION),
-                    entries, values);
-
-            initializeAsciiArmor(
-                    (CheckBoxPreference) findPreference(Constants.Pref.DEFAULT_ASCII_ARMOR));
-
-            initializeWriteVersionHeader(
-                    (CheckBoxPreference) findPreference(Constants.Pref.WRITE_VERSION_HEADER));
-
             initializeUseDefaultYubikeyPin(
                     (CheckBoxPreference) findPreference(Constants.Pref.USE_DEFAULT_YUBIKEY_PIN));
 
@@ -342,131 +302,6 @@ public class SettingsActivity extends PreferenceActivity {
                 });
     }
 
-    private static void initializeEncryptionAlgorithm(final IntegerListPreference mEncryptionAlgorithm) {
-        int valueIds[] = {
-                Constants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED,
-                Constants.OpenKeychainSymmetricKeyAlgorithmTags.AES_256,
-                Constants.OpenKeychainSymmetricKeyAlgorithmTags.AES_192,
-                Constants.OpenKeychainSymmetricKeyAlgorithmTags.AES_128,
-                Constants.OpenKeychainSymmetricKeyAlgorithmTags.TWOFISH,
-        };
-        String entries[] = {
-                "Use preferred algorithm",
-                "AES-256",
-                "AES-192",
-                "AES-128",
-                "Twofish",
-        };
-        String values[] = new String[valueIds.length];
-        for (int i = 0; i < values.length; ++i) {
-            values[i] = "" + valueIds[i];
-        }
-        mEncryptionAlgorithm.setEntries(entries);
-        mEncryptionAlgorithm.setEntryValues(values);
-        mEncryptionAlgorithm.setValue("" + sPreferences.getDefaultEncryptionAlgorithm());
-        mEncryptionAlgorithm.setSummary(mEncryptionAlgorithm.getEntry());
-        mEncryptionAlgorithm
-                .setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
-                    public boolean onPreferenceChange(Preference preference, Object newValue) {
-                        mEncryptionAlgorithm.setValue(newValue.toString());
-                        mEncryptionAlgorithm.setSummary(mEncryptionAlgorithm.getEntry());
-                        sPreferences.setDefaultEncryptionAlgorithm(Integer.parseInt(newValue
-                                .toString()));
-                        return false;
-                    }
-                });
-    }
-
-    private static void initializeHashAlgorithm(final IntegerListPreference mHashAlgorithm) {
-        int[] valueIds = new int[]{
-                Constants.OpenKeychainHashAlgorithmTags.USE_PREFERRED,
-                Constants.OpenKeychainHashAlgorithmTags.SHA512,
-                Constants.OpenKeychainHashAlgorithmTags.SHA384,
-                Constants.OpenKeychainHashAlgorithmTags.SHA256,
-                Constants.OpenKeychainHashAlgorithmTags.SHA224,
-                Constants.OpenKeychainHashAlgorithmTags.RIPEMD160,
-        };
-        String[] entries = new String[]{
-                "Use preferred algorithm",
-                "SHA-512",
-                "SHA-384",
-                "SHA-256",
-                "SHA-224",
-                "RIPEMD-160"};
-        String[] values = new String[valueIds.length];
-        for (int i = 0; i < values.length; ++i) {
-            values[i] = "" + valueIds[i];
-        }
-        mHashAlgorithm.setEntries(entries);
-        mHashAlgorithm.setEntryValues(values);
-        mHashAlgorithm.setValue("" + sPreferences.getDefaultHashAlgorithm());
-        mHashAlgorithm.setSummary(mHashAlgorithm.getEntry());
-        mHashAlgorithm.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
-            public boolean onPreferenceChange(Preference preference, Object newValue) {
-                mHashAlgorithm.setValue(newValue.toString());
-                mHashAlgorithm.setSummary(mHashAlgorithm.getEntry());
-                sPreferences.setDefaultHashAlgorithm(Integer.parseInt(newValue.toString()));
-                return false;
-            }
-        });
-    }
-
-    private static void initializeMessageCompression(final IntegerListPreference mMessageCompression,
-                                                     String[] entries, String[] values) {
-        mMessageCompression.setEntries(entries);
-        mMessageCompression.setEntryValues(values);
-        mMessageCompression.setValue("" + sPreferences.getDefaultMessageCompression());
-        mMessageCompression.setSummary(mMessageCompression.getEntry());
-        mMessageCompression
-                .setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
-                    public boolean onPreferenceChange(Preference preference, Object newValue) {
-                        mMessageCompression.setValue(newValue.toString());
-                        mMessageCompression.setSummary(mMessageCompression.getEntry());
-                        sPreferences.setDefaultMessageCompression(Integer.parseInt(newValue
-                                .toString()));
-                        return false;
-                    }
-                });
-    }
-
-    private static void initializeFileCompression
-            (final IntegerListPreference mFileCompression, String[] entries, String[] values) {
-        mFileCompression.setEntries(entries);
-        mFileCompression.setEntryValues(values);
-        mFileCompression.setValue("" + sPreferences.getDefaultFileCompression());
-        mFileCompression.setSummary(mFileCompression.getEntry());
-        mFileCompression.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
-            public boolean onPreferenceChange(Preference preference, Object newValue) {
-                mFileCompression.setValue(newValue.toString());
-                mFileCompression.setSummary(mFileCompression.getEntry());
-                sPreferences.setDefaultFileCompression(Integer.parseInt(newValue.toString()));
-                return false;
-            }
-        });
-    }
-
-    private static void initializeAsciiArmor(final CheckBoxPreference mAsciiArmor) {
-        mAsciiArmor.setChecked(sPreferences.getDefaultAsciiArmor());
-        mAsciiArmor.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
-            public boolean onPreferenceChange(Preference preference, Object newValue) {
-                mAsciiArmor.setChecked((Boolean) newValue);
-                sPreferences.setDefaultAsciiArmor((Boolean) newValue);
-                return false;
-            }
-        });
-    }
-
-    private static void initializeWriteVersionHeader(final CheckBoxPreference mWriteVersionHeader) {
-        mWriteVersionHeader.setChecked(sPreferences.getWriteVersionHeader());
-        mWriteVersionHeader.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
-            public boolean onPreferenceChange(Preference preference, Object newValue) {
-                mWriteVersionHeader.setChecked((Boolean) newValue);
-                sPreferences.setWriteVersionHeader((Boolean) newValue);
-                return false;
-            }
-        });
-    }
-
     private static void initializeSearchKeyserver(final CheckBoxPreference mSearchKeyserver) {
         Preferences.CloudSearchPrefs prefs = sPreferences.getCloudSearchPrefs();
         mSearchKeyserver.setChecked(prefs.searchKeyserver);
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Preferences.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Preferences.java
index 089702de6..44c1e6b6c 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Preferences.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Preferences.java
@@ -20,11 +20,7 @@ package org.sufficientlysecure.keychain.util;
 
 import android.content.Context;
 import android.content.SharedPreferences;
-import android.os.Build;
 
-import org.spongycastle.bcpg.CompressionAlgorithmTags;
-import org.spongycastle.bcpg.HashAlgorithmTags;
-import org.spongycastle.openpgp.PGPEncryptedData;
 import org.sufficientlysecure.keychain.Constants;
 import org.sufficientlysecure.keychain.Constants.Pref;
 
@@ -99,60 +95,6 @@ public class Preferences {
         editor.commit();
     }
 
-    public int getDefaultEncryptionAlgorithm() {
-        return mSharedPreferences.getInt(Constants.Pref.DEFAULT_ENCRYPTION_ALGORITHM,
-                PGPEncryptedData.AES_256);
-    }
-
-    public void setDefaultEncryptionAlgorithm(int value) {
-        SharedPreferences.Editor editor = mSharedPreferences.edit();
-        editor.putInt(Constants.Pref.DEFAULT_ENCRYPTION_ALGORITHM, value);
-        editor.commit();
-    }
-
-    public int getDefaultHashAlgorithm() {
-        return mSharedPreferences.getInt(Constants.Pref.DEFAULT_HASH_ALGORITHM,
-                HashAlgorithmTags.SHA256);
-    }
-
-    public void setDefaultHashAlgorithm(int value) {
-        SharedPreferences.Editor editor = mSharedPreferences.edit();
-        editor.putInt(Constants.Pref.DEFAULT_HASH_ALGORITHM, value);
-        editor.commit();
-    }
-
-    public int getDefaultMessageCompression() {
-        return mSharedPreferences.getInt(Constants.Pref.DEFAULT_MESSAGE_COMPRESSION,
-                CompressionAlgorithmTags.ZLIB);
-    }
-
-    public void setDefaultMessageCompression(int value) {
-        SharedPreferences.Editor editor = mSharedPreferences.edit();
-        editor.putInt(Constants.Pref.DEFAULT_MESSAGE_COMPRESSION, value);
-        editor.commit();
-    }
-
-    public int getDefaultFileCompression() {
-        return mSharedPreferences.getInt(Constants.Pref.DEFAULT_FILE_COMPRESSION,
-                CompressionAlgorithmTags.UNCOMPRESSED);
-    }
-
-    public void setDefaultFileCompression(int value) {
-        SharedPreferences.Editor editor = mSharedPreferences.edit();
-        editor.putInt(Constants.Pref.DEFAULT_FILE_COMPRESSION, value);
-        editor.commit();
-    }
-
-    public boolean getDefaultAsciiArmor() {
-        return mSharedPreferences.getBoolean(Constants.Pref.DEFAULT_ASCII_ARMOR, false);
-    }
-
-    public void setDefaultAsciiArmor(boolean value) {
-        SharedPreferences.Editor editor = mSharedPreferences.edit();
-        editor.putBoolean(Constants.Pref.DEFAULT_ASCII_ARMOR, value);
-        editor.commit();
-    }
-
     public boolean getCachedConsolidate() {
         return mSharedPreferences.getBoolean(Pref.CACHED_CONSOLIDATE, false);
     }
@@ -228,16 +170,6 @@ public class Preferences {
         editor.commit();
     }
 
-    public void setWriteVersionHeader(boolean conceal) {
-        SharedPreferences.Editor editor = mSharedPreferences.edit();
-        editor.putBoolean(Constants.Pref.WRITE_VERSION_HEADER, conceal);
-        editor.commit();
-    }
-
-    public boolean getWriteVersionHeader() {
-        return mSharedPreferences.getBoolean(Constants.Pref.WRITE_VERSION_HEADER, false);
-    }
-
     public void setSearchKeyserver(boolean searchKeyserver) {
         SharedPreferences.Editor editor = mSharedPreferences.edit();
         editor.putBoolean(Pref.SEARCH_KEYSERVER, searchKeyserver);
@@ -299,32 +231,9 @@ public class Preferences {
 
                     }
                     setKeyServers(servers.toArray(new String[servers.size()]));
-
-                    // migrate old uncompressed constant to new one
-                    if (mSharedPreferences.getInt(Constants.Pref.DEFAULT_FILE_COMPRESSION, 0)
-                            == 0x21070001) {
-                        setDefaultFileCompression(CompressionAlgorithmTags.UNCOMPRESSED);
-                    }
-
-                    // migrate away from MD5
-                    if (mSharedPreferences.getInt(Constants.Pref.DEFAULT_HASH_ALGORITHM, 0)
-                            == HashAlgorithmTags.MD5) {
-                        setDefaultHashAlgorithm(HashAlgorithmTags.SHA256);
-                    }
                 }
                 // fall through
                 case 4: {
-                    // for compatibility: change from SHA512 to SHA256
-                    if (mSharedPreferences.getInt(Constants.Pref.DEFAULT_HASH_ALGORITHM, 0)
-                            == HashAlgorithmTags.SHA512) {
-                        setDefaultHashAlgorithm(HashAlgorithmTags.SHA256);
-                    }
-                }
-                // fall through
-                case 5: {
-                    // use preferred hash and encryption algo setting
-                    setDefaultHashAlgorithm(Constants.OpenKeychainHashAlgorithmTags.USE_PREFERRED);
-                    setDefaultEncryptionAlgorithm(Constants.OpenKeychainSymmetricKeyAlgorithmTags.USE_PREFERRED);
                 }
             }
 
diff --git a/OpenKeychain/src/main/res/menu/encrypt_file_activity.xml b/OpenKeychain/src/main/res/menu/encrypt_file_activity.xml
index fd0a85d6c..9a26d1757 100644
--- a/OpenKeychain/src/main/res/menu/encrypt_file_activity.xml
+++ b/OpenKeychain/src/main/res/menu/encrypt_file_activity.xml
@@ -12,4 +12,9 @@
         android:id="@+id/check_delete_after_encrypt"
         android:title="@string/label_delete_after_encryption"
         android:checkable="true" />
+    <item
+        android:id="@+id/check_enable_compression"
+        android:title="@string/label_enable_compression"
+        android:checked="true"
+        android:checkable="true" />
 </menu>
\ No newline at end of file
diff --git a/OpenKeychain/src/main/res/menu/encrypt_text_activity.xml b/OpenKeychain/src/main/res/menu/encrypt_text_activity.xml
index 8deb59514..71d254bb9 100644
--- a/OpenKeychain/src/main/res/menu/encrypt_text_activity.xml
+++ b/OpenKeychain/src/main/res/menu/encrypt_text_activity.xml
@@ -4,4 +4,9 @@
         android:id="@+id/check_use_symmetric"
         android:title="@string/label_symmetric"
         android:checkable="true" />
+    <item
+        android:id="@+id/check_enable_compression"
+        android:title="@string/label_enable_compression"
+        android:checked="true"
+        android:checkable="true" />
 </menu>
\ No newline at end of file
diff --git a/OpenKeychain/src/main/res/values/strings.xml b/OpenKeychain/src/main/res/values/strings.xml
index 207553620..147201bc4 100644
--- a/OpenKeychain/src/main/res/values/strings.xml
+++ b/OpenKeychain/src/main/res/values/strings.xml
@@ -161,6 +161,7 @@
     <string name="expiry_date_dialog_title">"Set expiry date"</string>
     <string name="label_first_keyserver_is_used">"(First keyserver listed is preferred)"</string>
     <string name="label_preferred">"preferred"</string>
+    <string name="label_enable_compression">"Enable compression"</string>
 
     <string name="user_id_no_name">"&lt;no name&gt;"</string>
     <string name="none">"&lt;none&gt;"</string>
diff --git a/OpenKeychain/src/main/res/xml/adv_preferences.xml b/OpenKeychain/src/main/res/xml/adv_preferences.xml
index 02986bdad..7dd649e5d 100644
--- a/OpenKeychain/src/main/res/xml/adv_preferences.xml
+++ b/OpenKeychain/src/main/res/xml/adv_preferences.xml
@@ -1,52 +1,23 @@
 <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
-    <PreferenceCategory android:title="@string/section_defaults">
-        <CheckBoxPreference
-            android:key="writeVersionHeader"
-            android:persistent="false"
-            android:title="@string/label_write_version_header"
-            android:summary="@string/label_write_version_header_summary" />
-        <org.sufficientlysecure.keychain.ui.widget.IntegerListPreference
-            android:key="defaultEncryptionAlgorithm"
-            android:persistent="false"
-            android:title="@string/label_encryption_algorithm" />
-        <org.sufficientlysecure.keychain.ui.widget.IntegerListPreference
-            android:key="defaultHashAlgorithm"
-            android:persistent="false"
-            android:title="@string/label_hash_algorithm" />
-        <org.sufficientlysecure.keychain.ui.widget.IntegerListPreference
-            android:key="defaultMessageCompression"
-            android:persistent="false"
-            android:title="@string/label_message_compression" />
-        <org.sufficientlysecure.keychain.ui.widget.IntegerListPreference
-            android:key="defaultFileCompression"
-            android:persistent="false"
-            android:title="@string/label_file_compression" />
-        <CheckBoxPreference
-            android:key="defaultAsciiArmor"
-            android:persistent="false"
-            android:title="@string/label_ascii_armor" />
-    </PreferenceCategory>
-    <PreferenceCategory android:title="@string/section_passphrase_cache">
-        <org.sufficientlysecure.keychain.ui.widget.IntegerListPreference
-            android:entries="@array/passphrase_cache_ttl_entries"
-            android:entryValues="@array/passphrase_cache_ttl_values"
-            android:key="passphraseCacheTtl"
-            android:persistent="false"
-            android:title="@string/label_passphrase_cache_ttl" />
-        <CheckBoxPreference
-            android:key="passphraseCacheSubs"
-            android:persistent="false"
-            android:title="@string/label_passphrase_cache_subs" />
-        <CheckBoxPreference
-            android:key="useDefaultYubikeyPin"
-            android:persistent="false"
-            android:defaultValue="true"
-            android:title="@string/label_use_default_yubikey_pin"
-            android:summary="@string/label_label_use_default_yubikey_pin_summary" />
-        <CheckBoxPreference
-            android:key="useNumKeypadForYubikeyPin"
-            android:persistent="false"
-            android:defaultValue="false"
-            android:title="@string/label_use_num_keypad_for_yubikey_pin" />
-    </PreferenceCategory>
+    <org.sufficientlysecure.keychain.ui.widget.IntegerListPreference
+        android:entries="@array/passphrase_cache_ttl_entries"
+        android:entryValues="@array/passphrase_cache_ttl_values"
+        android:key="passphraseCacheTtl"
+        android:persistent="false"
+        android:title="@string/label_passphrase_cache_ttl" />
+    <CheckBoxPreference
+        android:key="passphraseCacheSubs"
+        android:persistent="false"
+        android:title="@string/label_passphrase_cache_subs" />
+    <CheckBoxPreference
+        android:key="useDefaultYubikeyPin"
+        android:persistent="false"
+        android:defaultValue="true"
+        android:title="@string/label_use_default_yubikey_pin"
+        android:summary="@string/label_label_use_default_yubikey_pin_summary" />
+    <CheckBoxPreference
+        android:key="useNumKeypadForYubikeyPin"
+        android:persistent="false"
+        android:defaultValue="false"
+        android:title="@string/label_use_num_keypad_for_yubikey_pin" />
 </PreferenceScreen>
diff --git a/OpenKeychain/src/main/res/xml/preference_headers.xml b/OpenKeychain/src/main/res/xml/preference_headers.xml
index 347394b06..e3447ff48 100644
--- a/OpenKeychain/src/main/res/xml/preference_headers.xml
+++ b/OpenKeychain/src/main/res/xml/preference_headers.xml
@@ -4,5 +4,5 @@
         android:title="@string/section_cloud_search" />
     <header
         android:fragment="org.sufficientlysecure.keychain.ui.SettingsActivity$AdvancedPrefsFragment"
-        android:title="@string/section_advanced" />
+        android:title="@string/section_passphrase_cache" />
 </preference-headers>