android: Properly handle shorter types in BufferedByteWriter

In Java all integer types are signed, when a negative integer is casted
to a larger type (e.g. int to long) then due to sign extension the upper
bytes are not 0.  So writing that value to a byte array does not produce
the expected result.  By overloading the putX() methods we make sure to
upcast the values correctly.

1 files changed, 86 insertions, 0 deletions

diff --git a/src/frontends/android/app/src/main/java/org/strongswan/android/utils/BufferedByteWriter.java b/src/frontends/android/app/src/main/java/org/strongswan/android/utils/BufferedByteWriter.java
index efc728377..b31951c03 100644
--- a/src/frontends/android/app/src/main/java/org/strongswan/android/utils/BufferedByteWriter.java
+++ b/src/frontends/android/app/src/main/java/org/strongswan/android/utils/BufferedByteWriter.java
@@ -127,6 +127,16 @@ public class BufferedByteWriter
 	 * @param value
 	 * @return the writer
 	 */
+	public BufferedByteWriter put16(byte value)
+	{
+		return this.put16((short)(value & 0xFF));
+	}
+
+	/**
+	 * Write the given short value (16-bit) in big-endian order to the buffer
+	 * @param value
+	 * @return the writer
+	 */
 	public BufferedByteWriter put16(short value)
 	{
 		ensureCapacity(2);
@@ -139,6 +149,32 @@ public class BufferedByteWriter
 	 * @param value
 	 * @return the writer
 	 */
+	public BufferedByteWriter put24(byte value)
+	{
+		ensureCapacity(3);
+		mWriter.putShort((short)0);
+		mWriter.put(value);
+		return this;
+	}
+
+	/**
+	 * Write 24-bit of the given value in big-endian order to the buffer
+	 * @param value
+	 * @return the writer
+	 */
+	public BufferedByteWriter put24(short value)
+	{
+		ensureCapacity(3);
+		mWriter.put((byte)0);
+		mWriter.putShort(value);
+		return this;
+	}
+
+	/**
+	 * Write 24-bit of the given value in big-endian order to the buffer
+	 * @param value
+	 * @return the writer
+	 */
 	public BufferedByteWriter put24(int value)
 	{
 		ensureCapacity(3);
@@ -152,6 +188,26 @@ public class BufferedByteWriter
 	 * @param value
 	 * @return the writer
 	 */
+	public BufferedByteWriter put32(byte value)
+	{
+		return put32(value & 0xFF);
+	}
+
+	/**
+	 * Write the given int value (32-bit) in big-endian order to the buffer
+	 * @param value
+	 * @return the writer
+	 */
+	public BufferedByteWriter put32(short value)
+	{
+		return put32(value & 0xFFFF);
+	}
+
+	/**
+	 * Write the given int value (32-bit) in big-endian order to the buffer
+	 * @param value
+	 * @return the writer
+	 */
 	public BufferedByteWriter put32(int value)
 	{
 		ensureCapacity(4);
@@ -164,6 +220,36 @@ public class BufferedByteWriter
 	 * @param value
 	 * @return the writer
 	 */
+	public BufferedByteWriter put64(byte value)
+	{
+		return put64(value & 0xFFL);
+	}
+
+	/**
+	 * Write the given long value (64-bit) in big-endian order to the buffer
+	 * @param value
+	 * @return the writer
+	 */
+	public BufferedByteWriter put64(short value)
+	{
+		return put64(value & 0xFFFFL);
+	}
+
+	/**
+	 * Write the given long value (64-bit) in big-endian order to the buffer
+	 * @param value
+	 * @return the writer
+	 */
+	public BufferedByteWriter put64(int value)
+	{
+		return put64(value & 0xFFFFFFFFL);
+	}
+
+	/**
+	 * Write the given long value (64-bit) in big-endian order to the buffer
+	 * @param value
+	 * @return the writer
+	 */
 	public BufferedByteWriter put64(long value)
 	{
 		ensureCapacity(8);