diff --git a/src/Makefile.am b/src/Makefile.am
index 3f5f84ff..5c2ab85d 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -6,7 +6,7 @@ EXTRA_DIST = linux bsd solaris cygwin mingw raw_socket uml_socket openssl gcrypt
 
 tincd_SOURCES = \
 	xmalloc.c utils.c getopt.c getopt1.c list.c splay_tree.c dropin.c fake-getaddrinfo.c fake-getnameinfo.c \
-	cipher.c conf.c connection.c control.c crypto.c digest.c edge.c graph.c logger.c meta.c net.c net_packet.c net_setup.c \
+	buffer.c cipher.c conf.c connection.c control.c crypto.c digest.c edge.c graph.c logger.c meta.c net.c net_packet.c net_setup.c \
 	net_socket.c netutl.c node.c process.c protocol.c protocol_auth.c protocol_edge.c protocol_misc.c \
 	protocol_key.c protocol_subnet.c route.c rsa.c subnet.c tincd.c
 
@@ -26,7 +26,7 @@ INCLUDES = @INCLUDES@ -I$(top_builddir)
 
 noinst_HEADERS = \
 	xalloc.h utils.h getopt.h list.h splay_tree.h dropin.h fake-getaddrinfo.h fake-getnameinfo.h fake-gai-errnos.h ipv6.h ipv4.h ethernet.h \
-	cipher.h conf.h connection.h control.h control_common.h crypto.h device.h digest.h edge.h graph.h logger.h meta.h net.h netutl.h node.h process.h \
+	buffer.h cipher.h conf.h connection.h control.h control_common.h crypto.h device.h digest.h edge.h graph.h logger.h meta.h net.h netutl.h node.h process.h \
 	protocol.h route.h rsa.h rsagen.h subnet.h bsd/tunemu.h
 
 LIBS = @LIBS@ @LIBGCRYPT_LIBS@
diff --git a/src/buffer.c b/src/buffer.c
new file mode 100644
index 00000000..fc4fac0f
--- /dev/null
+++ b/src/buffer.c
@@ -0,0 +1,99 @@
+/*
+    buffer.c -- buffer management
+    Copyright (C) 2011 Guus Sliepen <guus@tinc-vpn.org>,
+
+    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; either version 2 of the License, or
+    (at your option) any later version.
+
+    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.
+*/
+
+#include "system.h"
+
+#include "buffer.h"
+#include "xalloc.h"
+
+// Make sure we can add size bytes to the buffer, and return a pointer to the start of those bytes.
+
+char *buffer_prepare(buffer_t *buffer, int size) {
+	if(!buffer->data) {
+		buffer->maxlen = size;
+		buffer->data = xmalloc(size);
+	} else {
+		if(buffer->offset && buffer->len + size > buffer->maxlen) {
+			memmove(buffer->data, buffer->data + buffer->offset, buffer->len - buffer->offset);
+			buffer->len -= buffer->offset;
+			buffer->offset = 0;
+		}
+
+		if(buffer->len + size > buffer->maxlen) {
+			buffer->maxlen = buffer->len + size;
+			buffer->data = xrealloc(buffer->data, buffer->maxlen);
+		}
+	}
+
+	buffer->len += size;
+	return buffer->data + buffer->offset;
+}
+
+// Copy data into the buffer.
+			
+char *buffer_add(buffer_t *buffer, const char *data, int size) {
+	memcpy(buffer_prepare(buffer, size), data, size);
+}
+
+// Remove given number of bytes from the buffer, return a pointer to the start of them.
+
+static char *buffer_consume(buffer_t *buffer, int size) {
+	char *start = buffer->data + buffer->offset;
+
+	buffer->offset += size;
+
+	if(buffer->offset >= buffer->len) {
+		buffer->offset = 0;
+		buffer->len = 0;
+	} else {
+		buffer->offset += size;
+	}
+
+	return start;
+}
+
+// Check if there is a complete line in the buffer, and if so, return it NULL-terminated.
+
+char *buffer_readline(buffer_t *buffer) {
+	char *newline = memchr(buffer->data + buffer->offset, '\n', buffer->len - buffer->offset);
+
+	if(!newline)
+		return NULL;
+
+	int len = newline + 1 - buffer->data + buffer->offset;
+	*newline = 0;
+	return buffer_consume(buffer, len);
+}
+
+// Check if we have enough bytes in the buffer, and if so, return a pointer to the start of them.
+
+char *buffer_read(buffer_t *buffer, int size) {
+	if(buffer->len - buffer->offset < size)
+		return NULL;
+
+	return buffer_consume(buffer, size);
+}
+
+void buffer_clear(buffer_t *buffer) {
+	free(buffer->data);
+	buffer->data = 0;
+	buffer->maxlen = 0;
+	buffer->len = 0;
+	buffer->offset = 0;
+}
diff --git a/src/buffer.h b/src/buffer.h
new file mode 100644
index 00000000..4d6f6726
--- /dev/null
+++ b/src/buffer.h
@@ -0,0 +1,17 @@
+#ifndef __TINC_BUFFER_H__
+#define __TINC_BUFFER_H__
+
+typedef struct buffer_t {
+	char *data;
+	int maxlen;
+	int len;
+	int offset;
+} buffer_t;
+
+extern char *buffer_prepare(buffer_t *buffer, int size);
+extern char *buffer_add(buffer_t *buffer, const char *data, int size);
+extern char *buffer_readline(buffer_t *buffer);
+extern char *buffer_read(buffer_t *buffer, int size);
+extern void buffer_clear(buffer_t *buffer);
+
+#endif