Add StreamUtil.readBodyLen function

Author: gefeili

pg/src/main/java/org/bouncycastle/bcpg/BCPGInputStream.java

@@ -11,7 +11,8 @@
  * Stream reader for PGP objects
  */
 public class BCPGInputStream
-    extends InputStream implements PacketTags
+    extends InputStream
+    implements PacketTags
 {
     /**
      * If the argument is a {@link BCPGInputStream}, return it.
@@ -29,19 +30,19 @@ public static BCPGInputStream wrap(InputStream in)
         return new BCPGInputStream(in);
     }
 
-    InputStream    in;
-    boolean        next = false;
-    int            nextB;
+    InputStream in;
+    boolean next = false;
+    int nextB;
 
-    boolean        mNext = false;
-    int            mNextB;
+    boolean mNext = false;
+    int mNextB;
 
     public BCPGInputStream(
-        InputStream    in)
+        InputStream in)
     {
         this.in = in;
     }
-    
+
     public int available()
         throws IOException
     {
@@ -113,9 +114,9 @@ public int read(
     }
 
     public void readFully(
-        byte[]    buf,
-        int       off,
-        int       len)
+        byte[] buf,
+        int off,
+        int len)
         throws IOException
     {
         if (Streams.readFully(this, buf, off, len) < len)
@@ -131,7 +132,7 @@ public byte[] readAll()
     }
 
     public void readFully(
-        byte[]    buf)
+        byte[] buf)
         throws IOException
     {
         readFully(buf, 0, buf.length);
@@ -141,7 +142,6 @@ public void readFully(
      * Obtains the tag of the next packet in the stream.
      *
      * @return the {@link PacketTags tag number}.
-     *
      * @throws IOException if an error occurs reading the tag from the stream.
      */
     public int nextPacketTag()
@@ -176,12 +176,13 @@ public int nextPacketTag()
 
     /**
      * Reads the next packet from the stream.
+     *
      * @throws IOException
      */
     public Packet readPacket()
         throws IOException
     {
-        int    hdr = this.read();
+        int hdr = this.read();
 
         if (hdr < 0)
         {
@@ -193,36 +194,17 @@ public Packet readPacket()
             throw new IOException("invalid header encountered");
         }
 
-        boolean    newPacket = (hdr & 0x40) != 0;
-        int        tag = 0;
-        int        bodyLen = 0;
-        boolean    partial = false;
+        boolean newPacket = (hdr & 0x40) != 0;
+        int tag = 0;
+        int bodyLen = 0;
+        boolean partial = false;
 
         if (newPacket)
         {
             tag = hdr & 0x3f;
-
-            int    l = this.read();
-
-            if (l < 192)
-            {
-                bodyLen = l;
-            }
-            else if (l <= 223)
-            {
-                int b = this.read();
-
-                bodyLen = ((l - 192) << 8) + (b) + 192;
-            }
-            else if (l == 255)
-            {
-                bodyLen = StreamUtil.read4OctetLength(this);
-            }
-            else
-            {
-                partial = true;
-                bodyLen = 1 << (l & 0x1f);
-            }
+            boolean[] flags = new boolean[3];
+            bodyLen = StreamUtil.readBodyLen(this, this, flags);
+            partial = flags[2];
         }
         else
         {
@@ -249,7 +231,7 @@ else if (l == 255)
             }
         }
 
-        BCPGInputStream    objStream;
+        BCPGInputStream objStream;
 
         if (bodyLen == 0 && partial)
         {
@@ -260,7 +242,7 @@ else if (l == 255)
             objStream = new BCPGInputStream(
                 new BufferedInputStream(new PartialInputStream(this, partial, bodyLen)));
         }
-  
+
         switch (tag)
         {
         case RESERVED:
@@ -314,9 +296,9 @@ else if (l == 255)
     }
 
     /**
-     * @deprecated use skipMarkerAndPaddingPackets
      * @return the tag for the next non-marker/padding packet
      * @throws IOException on a parsing issue.
+     * @deprecated use skipMarkerAndPaddingPackets
      */
     public int skipMarkerPackets()
         throws IOException
@@ -326,6 +308,7 @@ public int skipMarkerPackets()
 
     /**
      * skip any marker and padding packets found in the stream.
+     *
      * @return the tag for the next non-marker/padding packet
      * @throws IOException on a parsing issue.
      */
@@ -334,7 +317,7 @@ public int skipMarkerAndPaddingPackets()
     {
         int tag;
         while ((tag = nextPacketTag()) == PacketTags.MARKER
-             || tag == PacketTags.PADDING)
+            || tag == PacketTags.PADDING)
         {
             readPacket();
         }
@@ -350,20 +333,20 @@ public void close()
 
     /**
      * a stream that overlays our input stream, allowing the user to only read a segment of it.
-     *
+     * <p>
      * NB: dataLength will be negative if the segment length is in the upper range above 2**31.
      */
     private static class PartialInputStream
         extends InputStream
     {
-        private BCPGInputStream     in;
-        private boolean             partial;
-        private int                 dataLength;
+        private BCPGInputStream in;
+        private boolean partial;
+        private int dataLength;
 
         PartialInputStream(
-            BCPGInputStream  in,
-            boolean          partial,
-            int              dataLength)
+            BCPGInputStream in,
+            boolean partial,
+            int dataLength)
         {
             this.in = in;
             this.partial = partial;
@@ -392,32 +375,13 @@ public int available()
         private int loadDataLength()
             throws IOException
         {
-            int            l = in.read();
-
-            if (l < 0)
+            boolean[] flags = new boolean[3];
+            dataLength = StreamUtil.readBodyLen(in, in, flags);
+            if (flags[0])
             {
                 return -1;
             }
-
-            partial = false;
-            if (l < 192)
-            {
-                dataLength = l;
-            }
-            else if (l <= 223)
-            {
-                dataLength = ((l - 192) << 8) + (in.read()) + 192;
-            }
-            else if (l == 255)
-            {
-                dataLength = StreamUtil.read4OctetLength(in);
-            }
-            else
-            {
-                partial = true;
-                dataLength = 1 << (l & 0x1f);
-            }
-
+            partial = flags[2];
             return dataLength;
         }
 

pg/src/main/java/org/bouncycastle/bcpg/SignatureSubpacketInputStream.java

@@ -68,33 +68,17 @@ public int read()
     public SignatureSubpacket readPacket()
         throws IOException
     {
-        int l = this.read();
-        int bodyLen;
-
-        if (l < 0)
+        boolean[] flags = new boolean[3];
+        int bodyLen = StreamUtil.readBodyLen(this, in, flags);
+        if (flags[0])
         {
             return null;
         }
-
-        boolean isLongLength = false;
-
-        if (l < 192)
-        {
-            bodyLen = l;
-        }
-        else if (l <= 223)
-        {
-            bodyLen = ((l - 192) << 8) + (in.read()) + 192;
-        }
-        else if (l == 255)
-        {
-            isLongLength = true;
-            bodyLen = StreamUtil.read4OctetLength(in);
-        }
-        else
+        else if (flags[2])
         {
             throw new IOException("unexpected length header");
         }
+        boolean isLongLength = flags[1];
 
         int tag = in.read();
 

pg/src/main/java/org/bouncycastle/bcpg/StreamUtil.java

@@ -7,6 +7,8 @@
 import java.io.OutputStream;
 import java.nio.channels.FileChannel;
 
+import org.bouncycastle.util.Arrays;
+
 class StreamUtil
 {
     private static final long MAX_MEMORY = Runtime.getRuntime().maxMemory();
@@ -148,10 +150,39 @@ static int read4OctetLength(InputStream in)
 
     /**
      * Note: flags is an array of three boolean values:
-     * flags[0] indicates l is negative
-     * */
-//    static int readBodyLen(InputStream in, boolean[] flags){
-//        flags =
-//    }
+     * flags[0] indicates l is negative, flag for eof
+     * flags[1] indicates (is)longLength = true
+     * flags[2] indicate partial = true
+     */
+    static int readBodyLen(InputStream in, InputStream subIn, boolean[] flags)
+        throws IOException
+    {
+        Arrays.fill(flags, false);
+        int l = in.read();
+        int bodyLen = -1;
+        if (l < 0)
+        {
+            flags[0] = true;
+        }
+        if (l < 192)
+        {
+            bodyLen = l;
+        }
+        else if (l <= 223)
+        {
+            bodyLen = ((l - 192) << 8) + (subIn.read()) + 192;
+        }
+        else if (l == 255)
+        {
+            flags[1] = true;
+            bodyLen = StreamUtil.read4OctetLength(in);
+        }
+        else
+        {
+            flags[2] = true;
+            bodyLen = 1 << (l & 0x1f);
+        }
+        return bodyLen;
+    }
 
 }