Vendor import of OpenSSH.

1 files changed, 165 insertions, 0 deletions

diff --git a/crypto/openssh/compress.c b/crypto/openssh/compress.c
new file mode 100644
index 0000000..f4a8785
--- /dev/null
+++ b/crypto/openssh/compress.c
@@ -0,0 +1,165 @@
+/*
+ * 
+ * compress.c
+ * 
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * 
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * 
+ * Created: Wed Oct 25 22:12:46 1995 ylo
+ * 
+ * Interface to packet compression for ssh.
+ * 
+ */
+
+#include "includes.h"
+RCSID("$Id: compress.c,v 1.4 1999/11/24 19:53:46 markus Exp $");
+
+#include "ssh.h"
+#include "buffer.h"
+#include "zlib.h"
+
+static z_stream incoming_stream;
+static z_stream outgoing_stream;
+
+/*
+ * Initializes compression; level is compression level from 1 to 9
+ * (as in gzip).
+ */
+
+void 
+buffer_compress_init(int level)
+{
+	debug("Enabling compression at level %d.", level);
+	if (level < 1 || level > 9)
+		fatal("Bad compression level %d.", level);
+	inflateInit(&incoming_stream);
+	deflateInit(&outgoing_stream, level);
+}
+
+/* Frees any data structures allocated for compression. */
+
+void 
+buffer_compress_uninit()
+{
+	debug("compress outgoing: raw data %lu, compressed %lu, factor %.2f",
+	      outgoing_stream.total_in, outgoing_stream.total_out,
+	      outgoing_stream.total_in == 0 ? 0.0 :
+	      (double) outgoing_stream.total_out / outgoing_stream.total_in);
+	debug("compress incoming: raw data %lu, compressed %lu, factor %.2f",
+	      incoming_stream.total_out, incoming_stream.total_in,
+	      incoming_stream.total_out == 0 ? 0.0 :
+	      (double) incoming_stream.total_in / incoming_stream.total_out);
+	inflateEnd(&incoming_stream);
+	deflateEnd(&outgoing_stream);
+}
+
+/*
+ * Compresses the contents of input_buffer into output_buffer.  All packets
+ * compressed using this function will form a single compressed data stream;
+ * however, data will be flushed at the end of every call so that each
+ * output_buffer can be decompressed independently (but in the appropriate
+ * order since they together form a single compression stream) by the
+ * receiver.  This appends the compressed data to the output buffer.
+ */
+
+void 
+buffer_compress(Buffer * input_buffer, Buffer * output_buffer)
+{
+	char buf[4096];
+	int status;
+
+	/* This case is not handled below. */
+	if (buffer_len(input_buffer) == 0)
+		return;
+
+	/* Input is the contents of the input buffer. */
+	outgoing_stream.next_in = buffer_ptr(input_buffer);
+	outgoing_stream.avail_in = buffer_len(input_buffer);
+
+	/* Loop compressing until deflate() returns with avail_out != 0. */
+	do {
+		/* Set up fixed-size output buffer. */
+		outgoing_stream.next_out = buf;
+		outgoing_stream.avail_out = sizeof(buf);
+
+		/* Compress as much data into the buffer as possible. */
+		status = deflate(&outgoing_stream, Z_PARTIAL_FLUSH);
+		switch (status) {
+		case Z_OK:
+			/* Append compressed data to output_buffer. */
+			buffer_append(output_buffer, buf,
+				      sizeof(buf) - outgoing_stream.avail_out);
+			break;
+		case Z_STREAM_END:
+			fatal("buffer_compress: deflate returned Z_STREAM_END");
+			/* NOTREACHED */
+		case Z_STREAM_ERROR:
+			fatal("buffer_compress: deflate returned Z_STREAM_ERROR");
+			/* NOTREACHED */
+		case Z_BUF_ERROR:
+			fatal("buffer_compress: deflate returned Z_BUF_ERROR");
+			/* NOTREACHED */
+		default:
+			fatal("buffer_compress: deflate returned %d", status);
+			/* NOTREACHED */
+		}
+	}
+	while (outgoing_stream.avail_out == 0);
+}
+
+/*
+ * Uncompresses the contents of input_buffer into output_buffer.  All packets
+ * uncompressed using this function will form a single compressed data
+ * stream; however, data will be flushed at the end of every call so that
+ * each output_buffer.  This must be called for the same size units that the
+ * buffer_compress was called, and in the same order that buffers compressed
+ * with that.  This appends the uncompressed data to the output buffer.
+ */
+
+void 
+buffer_uncompress(Buffer * input_buffer, Buffer * output_buffer)
+{
+	char buf[4096];
+	int status;
+
+	incoming_stream.next_in = buffer_ptr(input_buffer);
+	incoming_stream.avail_in = buffer_len(input_buffer);
+
+	incoming_stream.next_out = buf;
+	incoming_stream.avail_out = sizeof(buf);
+
+	for (;;) {
+		status = inflate(&incoming_stream, Z_PARTIAL_FLUSH);
+		switch (status) {
+		case Z_OK:
+			buffer_append(output_buffer, buf,
+				      sizeof(buf) - incoming_stream.avail_out);
+			incoming_stream.next_out = buf;
+			incoming_stream.avail_out = sizeof(buf);
+			break;
+		case Z_STREAM_END:
+			fatal("buffer_uncompress: inflate returned Z_STREAM_END");
+			/* NOTREACHED */
+		case Z_DATA_ERROR:
+			fatal("buffer_uncompress: inflate returned Z_DATA_ERROR");
+			/* NOTREACHED */
+		case Z_STREAM_ERROR:
+			fatal("buffer_uncompress: inflate returned Z_STREAM_ERROR");
+			/* NOTREACHED */
+		case Z_BUF_ERROR:
+			/*
+			 * Comments in zlib.h say that we should keep calling
+			 * inflate() until we get an error.  This appears to
+			 * be the error that we get.
+			 */
+			return;
+		case Z_MEM_ERROR:
+			fatal("buffer_uncompress: inflate returned Z_MEM_ERROR");
+			/* NOTREACHED */
+		default:
+			fatal("buffer_uncompress: inflate returned %d", status);
+		}
+	}
+}