Wip: Adopt changes from the SOP specification version 2

pgpainless-cli/src/test/java/org/pgpainless/cli/commands/EncryptDecryptTest.java

@@ -101,7 +101,6 @@ public class EncryptDecryptTest {
         msgAscOut.close();
 
         File verifyFile = new File(tempDir, "verify.txt");
-        assertTrue(verifyFile.createNewFile());
 
         FileInputStream msgAscIn = new FileInputStream(msgAscFile);
         System.setIn(msgAscIn);

pgpainless-sop/src/main/java/org/pgpainless/sop/ArmorImpl.java

@@ -38,7 +38,7 @@ public class ArmorImpl implements Armor {
 
     @Override
     public Armor label(ArmorLabel label) throws SOPGPException.UnsupportedOption {
-        throw new SOPGPException.UnsupportedOption();
+        throw new SOPGPException.UnsupportedOption("Setting custom Armor labels not supported.");
     }
 
     @Override

pgpainless-sop/src/main/java/org/pgpainless/sop/DecryptImpl.java

@@ -87,7 +87,7 @@ public class DecryptImpl implements Decrypt {
 
     @Override
     public DecryptImpl withSessionKey(SessionKey sessionKey) throws SOPGPException.UnsupportedOption {
-        throw new SOPGPException.UnsupportedOption();
+        throw new SOPGPException.UnsupportedOption("Setting custom session key not supported.");
     }
 
     @Override

pgpainless-sop/src/main/java/org/pgpainless/sop/GenerateKeyImpl.java

@@ -87,7 +87,7 @@ public class GenerateKeyImpl implements GenerateKey {
                 }
             };
         } catch (InvalidAlgorithmParameterException | NoSuchAlgorithmException e) {
-            throw new SOPGPException.UnsupportedAsymmetricAlgo(e);
+            throw new SOPGPException.UnsupportedAsymmetricAlgo("Unsupported asymmetric algorithm.", e);
         } catch (PGPException e) {
             throw new RuntimeException(e);
         }

sop-java-picocli/src/main/java/sop/cli/picocli/SOPExceptionExitCodeMapper.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2021 Paul Schaub.
+ *
+ * Licensed 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, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package sop.cli.picocli;
+
+import picocli.CommandLine;
+import sop.exception.SOPGPException;
+
+public class SOPExceptionExitCodeMapper implements CommandLine.IExitCodeExceptionMapper {
+
+    @Override
+    public int getExitCode(Throwable exception) {
+        if (exception instanceof SOPGPException) {
+            return ((SOPGPException) exception).getExitCode();
+        }
+        if (exception instanceof CommandLine.UnmatchedArgumentException) {
+            CommandLine.UnmatchedArgumentException ex = (CommandLine.UnmatchedArgumentException) exception;
+            // Unmatched option of subcommand (eg. `generate-key -k`)
+            if (ex.isUnknownOption()) {
+                return SOPGPException.UnsupportedOption.EXIT_CODE;
+            }
+            // Unmatched subcommand
+            return SOPGPException.UnsupportedSubcommand.EXIT_CODE;
+        }
+        // Invalid option (eg. `--label Invalid`)
+        if (exception instanceof CommandLine.ParameterException) {
+            return SOPGPException.UnsupportedOption.EXIT_CODE;
+        }
+
+        // Others, like IOException etc.
+        return 1;
+    }
+}

sop-java-picocli/src/main/java/sop/cli/picocli/SOPExecutionExceptionHandler.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2021 Paul Schaub.
+ *
+ * Licensed 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, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package sop.cli.picocli;
+
+import picocli.CommandLine;
+
+public class SOPExecutionExceptionHandler implements CommandLine.IExecutionExceptionHandler {
+
+    @Override
+    public int handleExecutionException(Exception ex, CommandLine commandLine, CommandLine.ParseResult parseResult) throws Exception {
+        int exitCode = commandLine.getExitCodeExceptionMapper() != null ?
+                commandLine.getExitCodeExceptionMapper().getExitCode(ex) :
+                commandLine.getCommandSpec().exitCodeOnExecutionException();
+        CommandLine.Help.ColorScheme colorScheme = commandLine.getColorScheme();
+        // CHECKSTYLE:OFF
+        if (ex.getMessage() != null) {
+            commandLine.getErr().println(colorScheme.errorText(ex.getMessage()));
+        }
+        ex.printStackTrace(commandLine.getErr());
+        // CHECKSTYLE:ON
+
+        return exitCode;
+    }
+}

sop-java-picocli/src/main/java/sop/cli/picocli/SopCLI.java

@@ -58,6 +58,8 @@ public class SopCLI {
     public static int execute(String[] args) {
         return new CommandLine(SopCLI.class)
                 .setCommandName(EXECUTABLE_NAME)
+                .setExecutionExceptionHandler(new SOPExecutionExceptionHandler())
+                .setExitCodeExceptionMapper(new SOPExceptionExitCodeMapper())
                 .setCaseInsensitiveEnumValuesAllowed(true)
                 .execute(args);
     }

sop-java-picocli/src/main/java/sop/cli/picocli/commands/DecryptCmd.java

@@ -32,7 +32,6 @@ import sop.ReadyWithResult;
 import sop.SessionKey;
 import sop.Verification;
 import sop.cli.picocli.DateParser;
-import sop.cli.picocli.Print;
 import sop.cli.picocli.SopCLI;
 import sop.exception.SOPGPException;
 import sop.operation.Decrypt;
@@ -93,9 +92,13 @@ public class DecryptCmd implements Runnable {
 
     @Override
     public void run() {
-        unlinkExistingVerifyOut(verifyOut);
+        throwIfVerifyOutExists(verifyOut);
 
         Decrypt decrypt = SopCLI.getSop().decrypt();
+        if (decrypt == null) {
+            throw new SOPGPException.UnsupportedSubcommand("Subcommand 'decrypt' not implemented.");
+        }
+
         setNotAfter(notAfter, decrypt);
         setNotBefore(notBefore, decrypt);
         setWithPasswords(withPassword, decrypt);
@@ -104,65 +107,63 @@ public class DecryptCmd implements Runnable {
         setDecryptWith(keys, decrypt);
 
         if (verifyOut != null && certs.isEmpty()) {
-            Print.errln("--verify-out is requested, but no --verify-with was provided.");
+            throw new SOPGPException.IncompleteVerification("--verify-out is requested, but no --verify-with was provided.");
-            System.exit(23);
         }
 
         try {
             ReadyWithResult<DecryptionResult> ready = decrypt.ciphertext(System.in);
             DecryptionResult result = ready.writeTo(System.out);
-            if (sessionKeyOut != null) {
+            writeSessionKeyOut(result);
-                if (sessionKeyOut.exists()) {
+            writeVerifyOut(result);
-                    Print.errln("File " + sessionKeyOut.getAbsolutePath() + " already exists.");
-                    Print.trace(new SOPGPException.OutputExists());
-                    System.exit(1);
-                }
-
-                try (FileOutputStream outputStream = new FileOutputStream(sessionKeyOut)) {
-                    if (!result.getSessionKey().isPresent()) {
-                        Print.errln("Session key not extracted. Possibly the feature is not supported.");
-                        System.exit(SOPGPException.UnsupportedOption.EXIT_CODE);
-                    } else {
-                        SessionKey sessionKey = result.getSessionKey().get();
-                        outputStream.write(sessionKey.getAlgorithm());
-                        outputStream.write(sessionKey.getKey());
-                    }
-                }
-            }
-            if (verifyOut != null) {
-                if (!verifyOut.createNewFile()) {
-                    throw new IOException("Cannot create file " + verifyOut.getAbsolutePath());
-                }
-                try (FileOutputStream outputStream = new FileOutputStream(verifyOut)) {
-                    PrintWriter writer = new PrintWriter(outputStream);
-                    for (Verification verification : result.getVerifications()) {
-                        // CHECKSTYLE:OFF
-                        writer.println(verification.toString());
-                        // CHECKSTYLE:ON
-                    }
-                    writer.flush();
-                }
-            }
         } catch (SOPGPException.BadData badData) {
-            Print.errln("No valid OpenPGP message found on Standard Input.");
+            throw new SOPGPException.BadData("No valid OpenPGP message found on Standard Input.", badData);
-            Print.trace(badData);
+        } catch (IOException ioException) {
-            System.exit(badData.getExitCode());
+            throw new RuntimeException(ioException);
-        } catch (SOPGPException.MissingArg missingArg) {
+        }
-            Print.errln("Missing arguments.");
+    }
-            Print.trace(missingArg);
+
-            System.exit(missingArg.getExitCode());
+    private void writeVerifyOut(DecryptionResult result) throws IOException {
-        } catch (IOException e) {
+        if (verifyOut != null) {
-            Print.errln("IO Error.");
+            if (!verifyOut.createNewFile()) {
-            Print.trace(e);
+                throw new IOException("Cannot create file " + verifyOut.getAbsolutePath());
-            System.exit(1);
+            }
-        } catch (SOPGPException.NoSignature noSignature) {
+            try (FileOutputStream outputStream = new FileOutputStream(verifyOut)) {
-            Print.errln("No verifiable signature found.");
+                PrintWriter writer = new PrintWriter(outputStream);
-            Print.trace(noSignature);
+                for (Verification verification : result.getVerifications()) {
-            System.exit(noSignature.getExitCode());
+                    // CHECKSTYLE:OFF
-        } catch (SOPGPException.CannotDecrypt cannotDecrypt) {
+                    writer.println(verification.toString());
-            Print.errln("Cannot decrypt.");
+                    // CHECKSTYLE:ON
-            Print.trace(cannotDecrypt);
+                }
-            System.exit(cannotDecrypt.getExitCode());
+                writer.flush();
+            }
+        }
+    }
+
+    private void writeSessionKeyOut(DecryptionResult result) throws IOException {
+        if (sessionKeyOut != null) {
+            if (sessionKeyOut.exists()) {
+                throw new SOPGPException.OutputExists("Target " + sessionKeyOut.getAbsolutePath() + " of option --session-key-out already exists.");
+            }
+
+            try (FileOutputStream outputStream = new FileOutputStream(sessionKeyOut)) {
+                if (!result.getSessionKey().isPresent()) {
+                    throw new SOPGPException.UnsupportedOption("Session key not extracted. Possibly the feature --session-key-out is not supported.");
+                } else {
+                    SessionKey sessionKey = result.getSessionKey().get();
+                    outputStream.write(sessionKey.getAlgorithm());
+                    outputStream.write(sessionKey.getKey());
+                }
+            }
+        }
+    }
+
+    private void throwIfVerifyOutExists(File verifyOut) throws SOPGPException.OutputExists {
+        if (verifyOut == null) {
+            return;
+        }
+
+        if (verifyOut.exists()) {
+            throw new SOPGPException.OutputExists("Target " + verifyOut.getAbsolutePath() + " of option --verify-out already exists.");
         }
     }
 
@@ -171,25 +172,13 @@ public class DecryptCmd implements Runnable {
             try (FileInputStream keyIn = new FileInputStream(key)) {
                 decrypt.withKey(keyIn);
             } catch (SOPGPException.KeyIsProtected keyIsProtected) {
-                Print.errln("Key in file " + key.getAbsolutePath() + " is password protected.");
+                throw new SOPGPException.KeyIsProtected("Key in file " + key.getAbsolutePath() + " is password protected.", keyIsProtected);
-                Print.trace(keyIsProtected);
-                System.exit(1);
-            } catch (SOPGPException.UnsupportedAsymmetricAlgo unsupportedAsymmetricAlgo) {
-                Print.errln("Key uses unsupported asymmetric algorithm.");
-                Print.trace(unsupportedAsymmetricAlgo);
-                System.exit(unsupportedAsymmetricAlgo.getExitCode());
             } catch (SOPGPException.BadData badData) {
-                Print.errln("File " + key.getAbsolutePath() + " does not contain a private key.");
+                throw new SOPGPException.BadData("File " + key.getAbsolutePath() + " does not contain a private key.", badData);
-                Print.trace(badData);
-                System.exit(badData.getExitCode());
             } catch (FileNotFoundException e) {
-                Print.errln("File " + key.getAbsolutePath() + " does not exist.");
+                throw new SOPGPException.MissingInput("File " + key.getAbsolutePath() + " does not exist.", e);
-                Print.trace(e);
-                System.exit(1);
             } catch (IOException e) {
-                Print.errln("IO Error.");
+                throw new RuntimeException(e);
-                Print.trace(e);
-                System.exit(1);
             }
         }
     }
@@ -199,30 +188,11 @@ public class DecryptCmd implements Runnable {
             try (FileInputStream certIn = new FileInputStream(cert)) {
                 decrypt.verifyWithCert(certIn);
             } catch (FileNotFoundException e) {
-                Print.errln("File " + cert.getAbsolutePath() + " does not exist.");
+                throw new SOPGPException.MissingInput("File " + cert.getAbsolutePath() + " does not exist.", e);
-                Print.trace(e);
-                System.exit(1);
-            } catch (IOException e) {
-                Print.errln("IO Error.");
-                Print.trace(e);
-                System.exit(1);
             } catch (SOPGPException.BadData badData) {
-                Print.errln("File " + cert.getAbsolutePath() + " does not contain a valid certificate.");
+                throw new SOPGPException.BadData("File " + cert.getAbsolutePath() + " does not contain a valid certificate.", badData);
-                Print.trace(badData);
+            } catch (IOException ioException) {
-                System.exit(badData.getExitCode());
+                throw new RuntimeException(ioException);
-            }
-        }
-    }
-
-    private void unlinkExistingVerifyOut(File verifyOut) {
-        if (verifyOut == null) {
-            return;
-        }
-
-        if (verifyOut.exists()) {
-            if (!verifyOut.delete()) {
-                Print.errln("Cannot delete existing verification file" + verifyOut.getAbsolutePath());
-                System.exit(1);
             }
         }
     }
@@ -231,9 +201,7 @@ public class DecryptCmd implements Runnable {
         Pattern sessionKeyPattern = Pattern.compile("^\\d+:[0-9A-F]+$");
         for (String sessionKey : withSessionKey) {
             if (!sessionKeyPattern.matcher(sessionKey).matches()) {
-                Print.errln("Invalid session key format.");
+                throw new IllegalArgumentException("Session keys are expected in the format 'ALGONUM:HEXKEY'.");
-                Print.errln("Session keys are expected in the format 'ALGONUM:HEXKEY'");
-                System.exit(1);
             }
             String[] split = sessionKey.split(":");
             byte algorithm = (byte) Integer.parseInt(split[0]);
@@ -242,10 +210,7 @@ public class DecryptCmd implements Runnable {
             try {
                 decrypt.withSessionKey(new SessionKey(algorithm, key));
             } catch (SOPGPException.UnsupportedOption unsupportedOption) {
-                Print.errln("Unsupported option '--with-session-key'.");
+                throw new SOPGPException.UnsupportedOption("Unsupported option '--with-session-key'.", unsupportedOption);
-                Print.trace(unsupportedOption);
-                System.exit(unsupportedOption.getExitCode());
-                return;
             }
         }
     }
@@ -254,14 +219,8 @@ public class DecryptCmd implements Runnable {
         for (String password : withPassword) {
             try {
                 decrypt.withPassword(password);
-            } catch (SOPGPException.PasswordNotHumanReadable passwordNotHumanReadable) {
-                Print.errln("Password not human readable.");
-                Print.trace(passwordNotHumanReadable);
-                System.exit(passwordNotHumanReadable.getExitCode());
             } catch (SOPGPException.UnsupportedOption unsupportedOption) {
-                Print.errln("Unsupported option '--with-password'.");
+                throw new SOPGPException.UnsupportedOption("Unsupported option '--with-password'.", unsupportedOption);
-                Print.trace(unsupportedOption);
-                System.exit(unsupportedOption.getExitCode());
             }
         }
     }
@@ -271,9 +230,7 @@ public class DecryptCmd implements Runnable {
         try {
             decrypt.verifyNotAfter(notAfterDate);
         } catch (SOPGPException.UnsupportedOption unsupportedOption) {
-            Print.errln("Option '--not-after' not supported.");
+            throw new SOPGPException.UnsupportedOption("Option '--not-after' not supported.", unsupportedOption);
-            Print.trace(unsupportedOption);
-            System.exit(unsupportedOption.getExitCode());
         }
     }
 
@@ -282,9 +239,7 @@ public class DecryptCmd implements Runnable {
         try {
             decrypt.verifyNotBefore(notBeforeDate);
         } catch (SOPGPException.UnsupportedOption unsupportedOption) {
-            Print.errln("Option '--not-before' not supported.");
+            throw new SOPGPException.UnsupportedOption("Option '--not-before' not supported.", unsupportedOption);
-            Print.trace(unsupportedOption);
-            System.exit(unsupportedOption.getExitCode());
         }
     }
 }

sop-java-picocli/src/main/java/sop/cli/picocli/commands/EncryptCmd.java

@@ -24,7 +24,6 @@ import java.util.List;
 
 import picocli.CommandLine;
 import sop.Ready;
-import sop.cli.picocli.Print;
 import sop.cli.picocli.SopCLI;
 import sop.enums.EncryptAs;
 import sop.exception.SOPGPException;
@@ -67,28 +66,19 @@ public class EncryptCmd implements Runnable {
             try {
                 encrypt.mode(type);
             } catch (SOPGPException.UnsupportedOption unsupportedOption) {
-                Print.errln("Unsupported option '--as'.");
+                throw new SOPGPException.UnsupportedOption("Unsupported option '--as'.", unsupportedOption);
-                Print.trace(unsupportedOption);
-                System.exit(unsupportedOption.getExitCode());
             }
         }
 
         if (withPassword.isEmpty() && certs.isEmpty()) {
-            Print.errln("At least one password or cert file required for encryption.");
+            throw new SOPGPException.MissingArg("At least one password or cert file required for encryption.");
-            System.exit(19);
         }
 
         for (String password : withPassword) {
             try {
                 encrypt.withPassword(password);
-            } catch (SOPGPException.PasswordNotHumanReadable passwordNotHumanReadable) {
-                Print.errln("Password is not human-readable.");
-                Print.trace(passwordNotHumanReadable);
-                System.exit(passwordNotHumanReadable.getExitCode());
             } catch (SOPGPException.UnsupportedOption unsupportedOption) {
-                Print.errln("Unsupported option '--with-password'.");
+                throw new SOPGPException.UnsupportedOption("Unsupported option '--with-password'.", unsupportedOption);
-                Print.trace(unsupportedOption);
-                System.exit(unsupportedOption.getExitCode());
             }
         }
 
@@ -96,29 +86,17 @@ public class EncryptCmd implements Runnable {
             try (FileInputStream keyIn = new FileInputStream(keyFile)) {
                 encrypt.signWith(keyIn);
             } catch (FileNotFoundException e) {
-                Print.errln("Key file " + keyFile.getAbsolutePath() + " not found.");
+                throw new SOPGPException.MissingInput("Key file " + keyFile.getAbsolutePath() + " not found.", e);
-                Print.trace(e);
-                System.exit(1);
             } catch (IOException e) {
-                Print.errln("IO Error.");
+                throw new RuntimeException(e);
-                Print.trace(e);
-                System.exit(1);
             } catch (SOPGPException.KeyIsProtected keyIsProtected) {
-                Print.errln("Key from " + keyFile.getAbsolutePath() + " is password protected.");
+                throw new SOPGPException.KeyIsProtected("Key from " + keyFile.getAbsolutePath() + " is password protected.", keyIsProtected);
-                Print.trace(keyIsProtected);
-                System.exit(1);
             } catch (SOPGPException.UnsupportedAsymmetricAlgo unsupportedAsymmetricAlgo) {
-                Print.errln("Key from " + keyFile.getAbsolutePath() + " has unsupported asymmetric algorithm.");
+                throw new SOPGPException.UnsupportedAsymmetricAlgo("Key from " + keyFile.getAbsolutePath() + " has unsupported asymmetric algorithm.", unsupportedAsymmetricAlgo);
-                Print.trace(unsupportedAsymmetricAlgo);
-                System.exit(unsupportedAsymmetricAlgo.getExitCode());
             } catch (SOPGPException.CertCannotSign certCannotSign) {
-                Print.errln("Key from " + keyFile.getAbsolutePath() + " cannot sign.");
+                throw new RuntimeException("Key from " + keyFile.getAbsolutePath() + " cannot sign.", certCannotSign);
-                Print.trace(certCannotSign);
-                System.exit(1);
             } catch (SOPGPException.BadData badData) {
-                Print.errln("Key file " + keyFile.getAbsolutePath() + " does not contain a valid OpenPGP private key.");
+                throw new SOPGPException.BadData("Key file " + keyFile.getAbsolutePath() + " does not contain a valid OpenPGP private key.", badData);
-                Print.trace(badData);
-                System.exit(badData.getExitCode());
             }
         }
 
@@ -126,25 +104,15 @@ public class EncryptCmd implements Runnable {
             try (FileInputStream certIn = new FileInputStream(certFile)) {
                 encrypt.withCert(certIn);
             } catch (FileNotFoundException e) {
-                Print.errln("Certificate file " + certFile.getAbsolutePath() + " not found.");
+                throw new SOPGPException.MissingInput("Certificate file " + certFile.getAbsolutePath() + " not found.", e);
-                Print.trace(e);
-                System.exit(1);
             } catch (IOException e) {
-                Print.errln("IO Error.");
+                throw new RuntimeException(e);
-                Print.trace(e);
-                System.exit(1);
             } catch (SOPGPException.UnsupportedAsymmetricAlgo unsupportedAsymmetricAlgo) {
-                Print.errln("Certificate from " + certFile.getAbsolutePath() + " has unsupported asymmetric algorithm.");
+                throw new SOPGPException.UnsupportedAsymmetricAlgo("Certificate from " + certFile.getAbsolutePath() + " has unsupported asymmetric algorithm.", unsupportedAsymmetricAlgo);
-                Print.trace(unsupportedAsymmetricAlgo);
-                System.exit(unsupportedAsymmetricAlgo.getExitCode());
             } catch (SOPGPException.CertCannotEncrypt certCannotEncrypt) {
-                Print.errln("Certificate from " + certFile.getAbsolutePath() + " is not capable of encryption.");
+                throw new SOPGPException.CertCannotEncrypt("Certificate from " + certFile.getAbsolutePath() + " is not capable of encryption.", certCannotEncrypt);
-                Print.trace(certCannotEncrypt);
-                System.exit(certCannotEncrypt.getExitCode());
             } catch (SOPGPException.BadData badData) {
-                Print.errln("Certificate file " + certFile.getAbsolutePath() + " does not contain a valid OpenPGP certificate.");
+                throw new SOPGPException.BadData("Certificate file " + certFile.getAbsolutePath() + " does not contain a valid OpenPGP certificate.", badData);
-                Print.trace(badData);
-                System.exit(badData.getExitCode());
             }
         }
 
@@ -156,9 +124,7 @@ public class EncryptCmd implements Runnable {
             Ready ready = encrypt.plaintext(System.in);
             ready.writeTo(System.out);
         } catch (IOException e) {
-            Print.errln("IO Error.");
+            throw new RuntimeException(e);
-            Print.trace(e);
-            System.exit(1);
         }
     }
 }

sop-java-picocli/src/main/java/sop/cli/picocli/commands/ExtractCertCmd.java

@@ -19,7 +19,6 @@ import java.io.IOException;
 
 import picocli.CommandLine;
 import sop.Ready;
-import sop.cli.picocli.Print;
 import sop.cli.picocli.SopCLI;
 import sop.exception.SOPGPException;
 import sop.operation.ExtractCert;
@@ -45,13 +44,9 @@ public class ExtractCertCmd implements Runnable {
             Ready ready = extractCert.key(System.in);
             ready.writeTo(System.out);
         } catch (IOException e) {
-            Print.errln("IO Error.");
+            throw new RuntimeException(e);
-            Print.trace(e);
-            System.exit(1);
         } catch (SOPGPException.BadData badData) {
-            Print.errln("Standard Input does not contain valid OpenPGP private key material.");
+            throw new SOPGPException.BadData("Standard Input does not contain valid OpenPGP private key material.", badData);
-            Print.trace(badData);
-            System.exit(badData.getExitCode());
         }
     }
 }

sop-java-picocli/src/test/java/sop/cli/picocli/commands/ArmorCmdTest.java

@@ -92,7 +92,7 @@ public class ArmorCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void ifLabelsUnsupportedExit37() throws SOPGPException.UnsupportedOption {
-        when(armor.label(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(armor.label(any())).thenThrow(new SOPGPException.UnsupportedOption("Custom Armor labels are not supported."));
 
         SopCLI.main(new String[] {"armor", "--label", "Sig"});
     }
@@ -100,7 +100,7 @@ public class ArmorCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void ifAllowNestedUnsupportedExit37() throws SOPGPException.UnsupportedOption {
-        when(armor.allowNested()).thenThrow(new SOPGPException.UnsupportedOption());
+        when(armor.allowNested()).thenThrow(new SOPGPException.UnsupportedOption("Allowing nested Armor not supported."));
 
         SopCLI.main(new String[] {"armor", "--allow-nested"});
     }

sop-java-picocli/src/test/java/sop/cli/picocli/commands/DecryptCmdTest.java

@@ -27,7 +27,6 @@ import java.io.BufferedReader;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileInputStream;
-import java.io.FileOutputStream;
 import java.io.FileReader;
 import java.io.IOException;
 import java.io.OutputStream;
@@ -115,7 +114,7 @@ public class DecryptCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void assertUnsupportedWithPasswordCausesExit37() throws SOPGPException.PasswordNotHumanReadable, SOPGPException.UnsupportedOption {
-        when(decrypt.withPassword(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(decrypt.withPassword(any())).thenThrow(new SOPGPException.UnsupportedOption("Decrypting with password not supported."));
         SopCLI.main(new String[] {"decrypt", "--with-password", "swordfish"});
     }
 
@@ -168,20 +167,20 @@ public class DecryptCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void assertUnsupportedNotAfterCausesExit37() throws SOPGPException.UnsupportedOption {
-        when(decrypt.verifyNotAfter(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(decrypt.verifyNotAfter(any())).thenThrow(new SOPGPException.UnsupportedOption("Setting upper signature date boundary not supported."));
         SopCLI.main(new String[] {"decrypt", "--not-after", "now"});
     }
 
     @Test
     @ExpectSystemExitWithStatus(37)
     public void assertUnsupportedNotBeforeCausesExit37() throws SOPGPException.UnsupportedOption {
-        when(decrypt.verifyNotBefore(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(decrypt.verifyNotBefore(any())).thenThrow(new SOPGPException.UnsupportedOption("Setting lower signature date boundary not supported."));
         SopCLI.main(new String[] {"decrypt", "--not-before", "now"});
     }
 
     @Test
-    @ExpectSystemExitWithStatus(1)
+    @ExpectSystemExitWithStatus(59)
-    public void assertExistingSessionKeyOutFileCausesExit1() throws IOException {
+    public void assertExistingSessionKeyOutFileCausesExit59() throws IOException {
         File tempFile = File.createTempFile("existing-session-key-", ".tmp");
         tempFile.deleteOnExit();
         SopCLI.main(new String[] {"decrypt", "--session-key-out", tempFile.getAbsolutePath()});
@@ -257,19 +256,28 @@ public class DecryptCmdTest {
     }
 
     @Test
-    @ExpectSystemExitWithStatus(1)
+    @ExpectSystemExitWithStatus(61)
-    public void unexistentCertFileCausesExit1() {
+    public void unexistentCertFileCausesExit61() {
         SopCLI.main(new String[] {"decrypt", "--verify-with", "invalid"});
     }
 
     @Test
-    public void existingVerifyOutFileIsUnlinkedBeforeVerification() throws IOException, SOPGPException.CannotDecrypt, SOPGPException.MissingArg, SOPGPException.BadData {
+    @ExpectSystemExitWithStatus(59)
+    public void existingVerifyOutCausesExit59() throws IOException {
         File certFile = File.createTempFile("existing-verify-out-cert", ".asc");
         File existingVerifyOut = File.createTempFile("existing-verify-out", ".tmp");
-        byte[] data = "some data".getBytes(StandardCharsets.UTF_8);
+
-        try (FileOutputStream out = new FileOutputStream(existingVerifyOut)) {
+        SopCLI.main(new String[] {"decrypt", "--verify-out", existingVerifyOut.getAbsolutePath(), "--verify-with", certFile.getAbsolutePath()});
-            out.write(data);
+    }
+
+    @Test
+    public void verifyOutIsProperlyWritten() throws IOException, SOPGPException.CannotDecrypt, SOPGPException.MissingArg, SOPGPException.BadData {
+        File certFile = File.createTempFile("verify-out-cert", ".asc");
+        File verifyOut = new File(certFile.getParent(), "verify-out.txt");
+        if (verifyOut.exists()) {
+            verifyOut.delete();
         }
+        verifyOut.deleteOnExit();
         Date date = UTCUtil.parseUTCDate("2021-07-11T20:58:23Z");
         when(decrypt.ciphertext(any())).thenReturn(new ReadyWithResult<DecryptionResult>() {
             @Override
@@ -283,8 +291,8 @@ public class DecryptCmdTest {
             }
         });
 
-        SopCLI.main(new String[] {"decrypt", "--verify-out", existingVerifyOut.getAbsolutePath(), "--verify-with", certFile.getAbsolutePath()});
+        SopCLI.main(new String[] {"decrypt", "--verify-out", verifyOut.getAbsolutePath(), "--verify-with", certFile.getAbsolutePath()});
-        try (BufferedReader reader = new BufferedReader(new FileReader(existingVerifyOut))) {
+        try (BufferedReader reader = new BufferedReader(new FileReader(verifyOut))) {
             String line = reader.readLine();
             assertEquals("2021-07-11T20:58:23Z 1B66A707819A920925BC6777C3E0AFC0B2DFF862 C8CD564EBF8D7BBA90611D8D071773658BF6BF86", line);
         }
@@ -317,14 +325,14 @@ public class DecryptCmdTest {
     }
 
     @Test
-    @ExpectSystemExitWithStatus(1)
+    @ExpectSystemExitWithStatus(61)
-    public void assertKeyFileNotFoundCausesExit1() {
+    public void assertKeyFileNotFoundCausesExit61() {
         SopCLI.main(new String[] {"decrypt", "nonexistent-key"});
     }
 
     @Test
-    @ExpectSystemExitWithStatus(1)
+    @ExpectSystemExitWithStatus(67)
-    public void assertProtectedKeyCausesExit1() throws IOException, SOPGPException.KeyIsProtected, SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.BadData {
+    public void assertProtectedKeyCausesExit67() throws IOException, SOPGPException.KeyIsProtected, SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.BadData {
         when(decrypt.withKey(any())).thenThrow(new SOPGPException.KeyIsProtected());
         File tempKeyFile = File.createTempFile("key-", ".tmp");
         SopCLI.main(new String[] {"decrypt", tempKeyFile.getAbsolutePath()});
@@ -333,7 +341,7 @@ public class DecryptCmdTest {
     @Test
     @ExpectSystemExitWithStatus(13)
     public void assertUnsupportedAlgorithmExceptionCausesExit13() throws SOPGPException.KeyIsProtected, SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.BadData, IOException {
-        when(decrypt.withKey(any())).thenThrow(new SOPGPException.UnsupportedAsymmetricAlgo(new IOException()));
+        when(decrypt.withKey(any())).thenThrow(new SOPGPException.UnsupportedAsymmetricAlgo("Unsupported asymmetric algorithm.", new IOException()));
         File tempKeyFile = File.createTempFile("key-", ".tmp");
         SopCLI.main(new String[] {"decrypt", tempKeyFile.getAbsolutePath()});
     }

sop-java-picocli/src/test/java/sop/cli/picocli/commands/EncryptCmdTest.java

@@ -65,7 +65,7 @@ public class EncryptCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void as_unsupportedEncryptAsCausesExit37() throws SOPGPException.UnsupportedOption {
-        when(encrypt.mode(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(encrypt.mode(any())).thenThrow(new SOPGPException.UnsupportedOption("Setting encryption mode not supported."));
 
         SopCLI.main(new String[] {"encrypt", "--as", "Binary"});
     }
@@ -95,7 +95,7 @@ public class EncryptCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void withPassword_unsupportedWithPasswordCausesExit37() throws SOPGPException.PasswordNotHumanReadable, SOPGPException.UnsupportedOption {
-        when(encrypt.withPassword(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(encrypt.withPassword(any())).thenThrow(new SOPGPException.UnsupportedOption("Encrypting with password not supported."));
 
         SopCLI.main(new String[] {"encrypt", "--with-password", "orange"});
     }
@@ -110,14 +110,14 @@ public class EncryptCmdTest {
     }
 
     @Test
-    @ExpectSystemExitWithStatus(1)
+    @ExpectSystemExitWithStatus(61)
-    public void signWith_nonExistentKeyFileCausesExit1() {
+    public void signWith_nonExistentKeyFileCausesExit61() {
         SopCLI.main(new String[] {"encrypt", "--with-password", "admin", "--sign-with", "nonExistent.asc"});
     }
 
     @Test
-    @ExpectSystemExitWithStatus(1)
+    @ExpectSystemExitWithStatus(67)
-    public void signWith_keyIsProtectedCausesExit1() throws SOPGPException.KeyIsProtected, SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.CertCannotSign, SOPGPException.BadData, IOException {
+    public void signWith_keyIsProtectedCausesExit67() throws SOPGPException.KeyIsProtected, SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.CertCannotSign, SOPGPException.BadData, IOException {
         when(encrypt.signWith(any())).thenThrow(new SOPGPException.KeyIsProtected());
         File keyFile = File.createTempFile("sign-with", ".asc");
         SopCLI.main(new String[] {"encrypt", "--sign-with", keyFile.getAbsolutePath(), "--with-password", "starship"});
@@ -126,7 +126,7 @@ public class EncryptCmdTest {
     @Test
     @ExpectSystemExitWithStatus(13)
     public void signWith_unsupportedAsymmetricAlgoCausesExit13() throws SOPGPException.KeyIsProtected, SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.CertCannotSign, SOPGPException.BadData, IOException {
-        when(encrypt.signWith(any())).thenThrow(new SOPGPException.UnsupportedAsymmetricAlgo(new Exception()));
+        when(encrypt.signWith(any())).thenThrow(new SOPGPException.UnsupportedAsymmetricAlgo("Unsupported asymmetric algorithm.", new Exception()));
         File keyFile = File.createTempFile("sign-with", ".asc");
         SopCLI.main(new String[] {"encrypt", "--with-password", "123456", "--sign-with", keyFile.getAbsolutePath()});
     }
@@ -148,15 +148,15 @@ public class EncryptCmdTest {
     }
 
     @Test
-    @ExpectSystemExitWithStatus(1)
+    @ExpectSystemExitWithStatus(61)
-    public void cert_nonExistentCertFileCausesExit1() {
+    public void cert_nonExistentCertFileCausesExit61() {
         SopCLI.main(new String[] {"encrypt", "invalid.asc"});
     }
 
     @Test
     @ExpectSystemExitWithStatus(13)
     public void cert_unsupportedAsymmetricAlgorithmCausesExit13() throws IOException, SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.CertCannotEncrypt, SOPGPException.BadData {
-        when(encrypt.withCert(any())).thenThrow(new SOPGPException.UnsupportedAsymmetricAlgo(new Exception()));
+        when(encrypt.withCert(any())).thenThrow(new SOPGPException.UnsupportedAsymmetricAlgo("Unsupported asymmetric algorithm.", new Exception()));
         File certFile = File.createTempFile("cert", ".asc");
         SopCLI.main(new String[] {"encrypt", certFile.getAbsolutePath()});
     }
@@ -164,7 +164,7 @@ public class EncryptCmdTest {
     @Test
     @ExpectSystemExitWithStatus(17)
     public void cert_certCannotEncryptCausesExit17() throws IOException, SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.CertCannotEncrypt, SOPGPException.BadData {
-        when(encrypt.withCert(any())).thenThrow(new SOPGPException.CertCannotEncrypt());
+        when(encrypt.withCert(any())).thenThrow(new SOPGPException.CertCannotEncrypt("Certificate cannot encrypt.", new Exception()));
         File certFile = File.createTempFile("cert", ".asc");
         SopCLI.main(new String[] {"encrypt", certFile.getAbsolutePath()});
     }

sop-java-picocli/src/test/java/sop/cli/picocli/commands/GenerateKeyCmdTest.java

@@ -91,7 +91,7 @@ public class GenerateKeyCmdTest {
     @Test
     @ExpectSystemExitWithStatus(13)
     public void unsupportedAsymmetricAlgorithmCausesExit13() throws SOPGPException.UnsupportedAsymmetricAlgo, SOPGPException.MissingArg, IOException {
-        when(generateKey.generate()).thenThrow(new SOPGPException.UnsupportedAsymmetricAlgo(new Exception()));
+        when(generateKey.generate()).thenThrow(new SOPGPException.UnsupportedAsymmetricAlgo("Unsupported asymmetric algorithm.", new Exception()));
         SopCLI.main(new String[] {"generate-key", "Alice"});
     }
 

sop-java-picocli/src/test/java/sop/cli/picocli/commands/SignCmdTest.java

@@ -74,7 +74,7 @@ public class SignCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void as_unsupportedOptionCausesExit37() throws SOPGPException.UnsupportedOption {
-        when(sign.mode(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(sign.mode(any())).thenThrow(new SOPGPException.UnsupportedOption("Setting signing mode not supported."));
         SopCLI.main(new String[] {"sign", "--as", "binary", keyFile.getAbsolutePath()});
     }
 

sop-java-picocli/src/test/java/sop/cli/picocli/commands/VerifyCmdTest.java

@@ -106,7 +106,7 @@ public class VerifyCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void notAfter_unsupportedOptionCausesExit37() throws SOPGPException.UnsupportedOption {
-        when(verify.notAfter(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(verify.notAfter(any())).thenThrow(new SOPGPException.UnsupportedOption("Setting upper signature date boundary not supported."));
         SopCLI.main(new String[] {"verify", "--not-after", "2019-10-29T18:36:45Z", signature.getAbsolutePath(), cert.getAbsolutePath()});
     }
 
@@ -133,7 +133,7 @@ public class VerifyCmdTest {
     @Test
     @ExpectSystemExitWithStatus(37)
     public void notBefore_unsupportedOptionCausesExit37() throws SOPGPException.UnsupportedOption {
-        when(verify.notBefore(any())).thenThrow(new SOPGPException.UnsupportedOption());
+        when(verify.notBefore(any())).thenThrow(new SOPGPException.UnsupportedOption("Setting lower signature date boundary not supported."));
         SopCLI.main(new String[] {"verify", "--not-before", "2019-10-29T18:36:45Z", signature.getAbsolutePath(), cert.getAbsolutePath()});
     }
 

sop-java/src/main/java/sop/exception/SOPGPException.java

@@ -15,7 +15,7 @@
  */
 package sop.exception;
 
-public class SOPGPException extends Exception {
+public abstract class SOPGPException extends RuntimeException {
 
     public SOPGPException() {
         super();
@@ -29,10 +29,21 @@ public class SOPGPException extends Exception {
         super(e);
     }
 
+    public SOPGPException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public abstract int getExitCode();
+
     public static class NoSignature extends SOPGPException {
 
         public static final int EXIT_CODE = 3;
 
+        public NoSignature() {
+            super("No verifiable signature found.");
+        }
+
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -42,10 +53,15 @@ public class SOPGPException extends Exception {
 
         public static final int EXIT_CODE = 13;
 
+        public UnsupportedAsymmetricAlgo(String message, Throwable e) {
+            super(message, e);
+        }
+
         public UnsupportedAsymmetricAlgo(Throwable e) {
             super(e);
         }
 
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -54,12 +70,17 @@ public class SOPGPException extends Exception {
     public static class CertCannotEncrypt extends SOPGPException {
         public static final int EXIT_CODE = 17;
 
+        public CertCannotEncrypt(String message, Throwable cause) {
+            super(message, cause);
+        }
+
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
     }
 
-    public static class CertCannotSign extends SOPGPException {
+    public static class CertCannotSign extends Exception {
 
     }
 
@@ -71,6 +92,7 @@ public class SOPGPException extends Exception {
             super(s);
         }
 
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -80,6 +102,11 @@ public class SOPGPException extends Exception {
 
         public static final int EXIT_CODE = 23;
 
+        public IncompleteVerification(String message) {
+            super(message);
+        }
+
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -89,6 +116,7 @@ public class SOPGPException extends Exception {
 
         public static final int EXIT_CODE = 29;
 
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -98,6 +126,7 @@ public class SOPGPException extends Exception {
 
         public static final int EXIT_CODE = 31;
 
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -107,6 +136,15 @@ public class SOPGPException extends Exception {
 
         public static final int EXIT_CODE = 37;
 
+        public UnsupportedOption(String message) {
+            super(message);
+        }
+
+        public UnsupportedOption(String message, Throwable cause) {
+            super(message, cause);
+        }
+
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -120,6 +158,11 @@ public class SOPGPException extends Exception {
             super(e);
         }
 
+        public BadData(String message, BadData badData) {
+            super(message, badData);
+        }
+
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -129,6 +172,7 @@ public class SOPGPException extends Exception {
 
         public static final int EXIT_CODE = 53;
 
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }
@@ -136,20 +180,80 @@ public class SOPGPException extends Exception {
 
     public static class OutputExists extends SOPGPException {
 
+        public static final int EXIT_CODE = 59;
+
+        public OutputExists(String message) {
+            super(message);
+        }
+
+        @Override
+        public int getExitCode() {
+            return EXIT_CODE;
+        }
+    }
+
+    public static class MissingInput extends SOPGPException {
+
+        public static final int EXIT_CODE = 61;
+
+        public MissingInput(String message, Throwable cause) {
+            super(message, cause);
+        }
+
+        @Override
+        public int getExitCode() {
+            return EXIT_CODE;
+        }
     }
 
     public static class KeyIsProtected extends SOPGPException {
 
+        public static final int EXIT_CODE = 67;
+
+        public KeyIsProtected() {
+            super();
+        }
+
+        public KeyIsProtected(String message, Throwable cause) {
+            super(message, cause);
+        }
+
+        @Override
+        public int getExitCode() {
+            return EXIT_CODE;
+        }
     }
 
-    public static class AmbiguousInput extends SOPGPException {
+    public static class UnsupportedSubcommand extends SOPGPException {
-
-    }
-
-    public static class NotImplemented extends SOPGPException {
 
         public static final int EXIT_CODE = 69;
 
+        public UnsupportedSubcommand(String message) {
+            super(message);
+        }
+
+        @Override
+        public int getExitCode() {
+            return EXIT_CODE;
+        }
+    }
+
+    public static class UnsupportedSpecialPrefix extends SOPGPException {
+
+        public static final int EXIT_CODE = 71;
+
+        @Override
+        public int getExitCode() {
+            return EXIT_CODE;
+        }
+    }
+
+
+    public static class AmbiguousInput extends SOPGPException {
+
+        public static final int EXIT_CODE = 73;
+
+        @Override
         public int getExitCode() {
             return EXIT_CODE;
         }