1 files changed, 186 insertions, 0 deletions
diff --git a/base/util/src/netscape/security/util/DerInputBuffer.java b/base/util/src/netscape/security/util/DerInputBuffer.java
new file mode 100644
index 000000000..7534f3d06
--- /dev/null
+++ b/base/util/src/netscape/security/util/DerInputBuffer.java
@@ -0,0 +1,186 @@
+// --- BEGIN COPYRIGHT BLOCK ---
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; version 2 of the License.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// (C) 2007 Red Hat, Inc.
+// All rights reserved.
+// --- END COPYRIGHT BLOCK ---
+package netscape.security.util;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+
+/**
+ * DER input buffer ... this is the main abstraction in the DER library
+ * which actively works with the "untyped byte stream" abstraction. It
+ * does so with impunity, since it's not intended to be exposed to the
+ * anyone who could violate the "typed value stream" DER model and hence
+ * corrupt the input stream of DER values.
+ * 
+ * @version 1.11
+ * @author David Brownell
+ */
+class DerInputBuffer extends ByteArrayInputStream implements Cloneable {
+
+    DerInputBuffer(byte[] buf) {
+        super(buf);
+    }
+
+    DerInputBuffer(byte[] buf, int offset, int len) {
+        super(buf, offset, len);
+    }
+
+    DerInputBuffer dup() {
+        try {
+            DerInputBuffer retval = (DerInputBuffer) clone();
+
+            retval.mark(Integer.MAX_VALUE);
+            return retval;
+        } catch (CloneNotSupportedException e) {
+            throw new IllegalArgumentException(e.toString());
+        }
+    }
+
+    byte[] toByteArray() {
+        int len = available();
+        if (len <= 0)
+            return null;
+        byte[] retval = new byte[len];
+
+        System.arraycopy(buf, pos, retval, 0, len);
+        return retval;
+    }
+
+    int peek() throws IOException {
+        if (pos >= count)
+            throw new IOException("out of data");
+        else
+            return buf[pos];
+    }
+
+    /**
+     * Compares this DerInputBuffer for equality with the specified
+     * object.
+     */
+    public boolean equals(Object other) {
+        if (other instanceof DerInputBuffer)
+            return equals((DerInputBuffer) other);
+        else
+            return false;
+    }
+
+    boolean equals(DerInputBuffer other) {
+        if (this == other)
+            return true;
+
+        int max = this.available();
+        if (other.available() != max)
+            return false;
+        for (int i = 0; i < max; i++) {
+            if (this.buf[this.pos + i] != other.buf[other.pos + i]) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    void truncate(int len) throws IOException {
+        if (len > available())
+            throw new IOException("insufficient data");
+        count = pos + len;
+    }
+
+    /**
+     * Returns the unsigned integer which takes up the specified number
+     * of bytes in this buffer.
+     */
+    BigInt getUnsigned(int len) throws IOException {
+        if (len > available())
+            throw new IOException("short read, getInteger");
+
+        /*
+         * A prepended zero is used to ensure that the integer is
+         * interpreted as unsigned even when the high order bit is
+         * zero.  We don't support signed BigInts.
+         *
+         * Fix this here ... BigInts aren't expected to have these,
+         * and stuff like signing (sigsize = f(modulus)) misbehaves.
+         */
+        if (len > 1 && buf[pos] == 0) {
+            len--;
+            skip(1);
+        }
+
+        /*
+         * Consume the rest of the buffer, returning its value as
+         * an unsigned integer.
+         */
+        byte[] bytes = new byte[len];
+
+        System.arraycopy(buf, pos, bytes, 0, len);
+        skip(len);
+        return new BigInt(bytes);
+    }
+
+    /**
+     * Returns the bit string which takes up the rest of this buffer.
+     * This bit string must be byte-aligned.
+     */
+    byte[] getBitString() {
+        if (pos >= count || buf[pos] != 0)
+            return null;
+        /*
+         * Just copy the data into an aligned, padded octet buffer,
+         * and consume the rest of the buffer.
+         */
+        int len = available();
+        byte[] retval = new byte[len - 1];
+
+        System.arraycopy(buf, pos + 1, retval, 0, len - 1);
+        pos = count;
+        return retval;
+    }
+
+    /**
+     * Returns the bit string which takes up the rest of this buffer.
+     * The bit string need not be byte-aligned.
+     */
+    BitArray getUnalignedBitString() {
+        if (pos >= count)
+            return null;
+        /*
+         * Just copy the data into an aligned, padded octet buffer,
+         * and consume the rest of the buffer.
+         */
+        int len = available();
+        byte[] bits = new byte[len - 1];
+        int length = bits.length * 8 - buf[pos]; // number of valid bits
+
+        System.arraycopy(buf, pos + 1, bits, 0, len - 1);
+
+        BitArray bitArray = new BitArray(length, bits);
+        pos = count;
+        return bitArray;
+    }
+
+    /**
+     * Package-access method to optimize output operations
+     */
+    void dump(OutputStream out, int length) throws IOException {
+        if (count < mark + length)
+            throw new IOException("short DER value (encode)");
+        out.write(buf, mark, length);
+    }
+
+}