From aa953428ee7c3cb8ebbbe251141352c7632aa53e Mon Sep 17 00:00:00 2001
From: Paul Schaub <vanitasvitae@fsfe.org>
Date: Sun, 6 Nov 2022 20:23:01 +0100
Subject: [PATCH] Be less finnicky about session key formats

---
 .../sop/cli/picocli/commands/DecryptCmd.java  | 22 +++++++++----------
 sop-java/src/main/java/sop/SessionKey.java    |  3 ++-
 .../test/java/sop/util/SessionKeyTest.java    |  8 +++++++
 3 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/sop-java-picocli/src/main/java/sop/cli/picocli/commands/DecryptCmd.java b/sop-java-picocli/src/main/java/sop/cli/picocli/commands/DecryptCmd.java
index e6ac82a..a7ebb73 100644
--- a/sop-java-picocli/src/main/java/sop/cli/picocli/commands/DecryptCmd.java
+++ b/sop-java-picocli/src/main/java/sop/cli/picocli/commands/DecryptCmd.java
@@ -175,24 +175,22 @@ public class DecryptCmd extends AbstractSopCmd {
     }
 
     private void setWithSessionKeys(List<String> withSessionKey, Decrypt decrypt) {
-        Pattern sessionKeyPattern = Pattern.compile("^\\d+:[0-9A-F]+$");
         for (String sessionKeyFile : withSessionKey) {
-            String sessionKey;
+            String sessionKeyString;
             try {
-                sessionKey = stringFromInputStream(getInput(sessionKeyFile));
+                sessionKeyString = stringFromInputStream(getInput(sessionKeyFile));
             } catch (IOException e) {
                 throw new RuntimeException(e);
             }
-            if (!sessionKeyPattern.matcher(sessionKey).matches()) {
-                String errorMsg = getMsg("sop.error.input.malformed_session_key");
-                throw new IllegalArgumentException(errorMsg);
-            }
-            String[] split = sessionKey.split(":");
-            byte algorithm = (byte) Integer.parseInt(split[0]);
-            byte[] key = HexUtil.hexToBytes(split[1]);
-
+            SessionKey sessionKey;
             try {
-                decrypt.withSessionKey(new SessionKey(algorithm, key));
+                sessionKey = SessionKey.fromString(sessionKeyString);
+            } catch (IllegalArgumentException e) {
+                String errorMsg = getMsg("sop.error.input.malformed_session_key");
+                throw new IllegalArgumentException(errorMsg, e);
+            }
+            try {
+                decrypt.withSessionKey(sessionKey);
             } catch (SOPGPException.UnsupportedOption unsupportedOption) {
                 String errorMsg = getMsg("sop.error.feature_support.option_not_supported", OPT_WITH_SESSION_KEY);
                 throw new SOPGPException.UnsupportedOption(errorMsg, unsupportedOption);
diff --git a/sop-java/src/main/java/sop/SessionKey.java b/sop-java/src/main/java/sop/SessionKey.java
index 2adcec4..3997032 100644
--- a/sop-java/src/main/java/sop/SessionKey.java
+++ b/sop-java/src/main/java/sop/SessionKey.java
@@ -12,7 +12,7 @@ import sop.util.HexUtil;
 
 public class SessionKey {
 
-    private static final Pattern PATTERN = Pattern.compile("^(\\d):([0-9a-fA-F]+)$");
+    private static final Pattern PATTERN = Pattern.compile("^(\\d):([0-9A-F]+)$");
 
     private final byte algorithm;
     private final byte[] sessionKey;
@@ -62,6 +62,7 @@ public class SessionKey {
     }
 
     public static SessionKey fromString(String string) {
+        string = string.trim().toUpperCase().replace("\n", "");
         Matcher matcher = PATTERN.matcher(string);
         if (!matcher.matches()) {
             throw new IllegalArgumentException("Provided session key does not match expected format.");
diff --git a/sop-java/src/test/java/sop/util/SessionKeyTest.java b/sop-java/src/test/java/sop/util/SessionKeyTest.java
index 2891d0d..db7e89f 100644
--- a/sop-java/src/test/java/sop/util/SessionKeyTest.java
+++ b/sop-java/src/test/java/sop/util/SessionKeyTest.java
@@ -20,6 +20,14 @@ public class SessionKeyTest {
         assertEquals(string, sessionKey.toString());
     }
 
+    @Test
+    public void fromLowerStringTest() {
+        String string = "9:FCA4BEAF687F48059CACC14FB019125CD57392BAB7037C707835925CBF9F7BCD";
+        String lowercaseWithTrailingNewLine = "9:fca4beaf687f48059cacc14fb019125cd57392bab7037c707835925cbf9f7bcd\n";
+        SessionKey sessionKey = SessionKey.fromString(lowercaseWithTrailingNewLine);
+        assertEquals(string, sessionKey.toString());
+    }
+
     @Test
     public void toStringTest() {
         SessionKey sessionKey = new SessionKey((byte) 9, HexUtil.hexToBytes("FCA4BEAF687F48059CACC14FB019125CD57392BAB7037C707835925CBF9F7BCD"));