Imported Upstream version 5.0.2

8 files changed, 2461 insertions, 0 deletions

diff --git a/src/libstrongswan/collections/blocking_queue.c b/src/libstrongswan/collections/blocking_queue.c
new file mode 100644
index 000000000..da3356970
--- /dev/null
+++ b/src/libstrongswan/collections/blocking_queue.c
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2012 Giuliano Grassi
+ * Copyright (C) 2012 Ralf Sager
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+#include "blocking_queue.h"
+
+#include <threading/mutex.h>
+#include <threading/thread.h>
+#include <threading/condvar.h>
+#include <collections/linked_list.h>
+
+typedef struct private_blocking_queue_t private_blocking_queue_t;
+
+/**
+ * Private data of a blocking_queue_t object.
+ */
+struct private_blocking_queue_t {
+
+	/**
+	 * Public part
+	 */
+	blocking_queue_t public;
+
+	/**
+	 * Linked list containing all items in the queue
+	 */
+	linked_list_t *list;
+
+	/**
+	 * Mutex used to synchronize access to the queue
+	 */
+	mutex_t *mutex;
+
+	/**
+	 * Condvar used to wait for items
+	 */
+	condvar_t *condvar;
+
+};
+
+METHOD(blocking_queue_t, enqueue, void,
+	private_blocking_queue_t *this, void *item)
+{
+	this->mutex->lock(this->mutex);
+	this->list->insert_first(this->list, item);
+	this->condvar->signal(this->condvar);
+	this->mutex->unlock(this->mutex);
+}
+
+METHOD(blocking_queue_t, dequeue, void*,
+	private_blocking_queue_t *this)
+{
+	bool oldstate;
+	void *item;
+
+
+	this->mutex->lock(this->mutex);
+	thread_cleanup_push((thread_cleanup_t)this->mutex->unlock, this->mutex);
+	/* ensure that a canceled thread does not dequeue any items */
+	thread_cancellation_point();
+	while (this->list->remove_last(this->list, &item) != SUCCESS)
+	{
+		oldstate = thread_cancelability(TRUE);
+		this->condvar->wait(this->condvar, this->mutex);
+		thread_cancelability(oldstate);
+	}
+	thread_cleanup_pop(TRUE);
+	return item;
+}
+
+METHOD(blocking_queue_t, destroy, void,
+	private_blocking_queue_t *this)
+{
+	this->list->destroy(this->list);
+	this->condvar->destroy(this->condvar);
+	this->mutex->destroy(this->mutex);
+	free(this);
+}
+
+METHOD(blocking_queue_t, destroy_offset, void,
+	private_blocking_queue_t *this, size_t offset)
+{
+	this->list->invoke_offset(this->list, offset);
+	destroy(this);
+}
+
+METHOD(blocking_queue_t, destroy_function, void,
+	private_blocking_queue_t *this, void (*fn)(void*))
+{
+	this->list->invoke_function(this->list, (linked_list_invoke_t)fn);
+	destroy(this);
+}
+
+/*
+ * Described in header.
+ */
+blocking_queue_t *blocking_queue_create()
+{
+	private_blocking_queue_t *this;
+
+	INIT(this,
+		.public = {
+			.enqueue = _enqueue,
+			.dequeue = _dequeue,
+			.destroy = _destroy,
+			.destroy_offset = _destroy_offset,
+			.destroy_function = _destroy_function,
+		},
+		.list = linked_list_create(),
+		.mutex = mutex_create(MUTEX_TYPE_DEFAULT),
+		.condvar = condvar_create(CONDVAR_TYPE_DEFAULT),
+	);
+
+	return &this->public;
+}
+
diff --git a/src/libstrongswan/collections/blocking_queue.h b/src/libstrongswan/collections/blocking_queue.h
new file mode 100644
index 000000000..9b014f719
--- /dev/null
+++ b/src/libstrongswan/collections/blocking_queue.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2012 Giuliano Grassi
+ * Copyright (C) 2012 Ralf Sager
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup blocking_queue blocking_queue
+ * @{ @ingroup collections
+ */
+
+#ifndef BLOCKING_QUEUE_H_
+#define BLOCKING_QUEUE_H_
+
+typedef struct blocking_queue_t blocking_queue_t;
+
+#include <library.h>
+
+/**
+ * Class implementing a synchronized blocking queue based on linked_list_t
+ */
+struct blocking_queue_t {
+
+	/**
+	 * Inserts a new item at the tail of the queue
+	 *
+	 * @param item		item to insert in queue
+	 */
+	void (*enqueue)(blocking_queue_t *this, void *item);
+
+	/**
+	 * Removes the first item in the queue and returns its value.
+	 * If the queue is empty, this call blocks until a new item is inserted.
+	 *
+	 * @note This is a thread cancellation point
+	 *
+	 * @return			removed item
+	 */
+	void *(*dequeue)(blocking_queue_t *this);
+
+	/**
+	 * Destroys a blocking_queue_t object.
+	 *
+	 * @note No thread must wait in dequeue() when this function is called
+	 */
+	void (*destroy)(blocking_queue_t *this);
+
+	/**
+	 * Destroys a queue and its objects using the given destructor.
+	 *
+	 * If a queue and the contained objects should be destroyed, use
+	 * destroy_offset. The supplied offset specifies the destructor to
+	 * call on each object. The offset may be calculated using the offsetof
+	 * macro, e.g.: queue->destroy_offset(queue, offsetof(object_t, destroy));
+	 *
+	 * @note No thread must wait in dequeue() when this function is called
+	 *
+	 * @param offset	offset of the objects destructor
+	 */
+	void (*destroy_offset)(blocking_queue_t *this, size_t offset);
+
+	/**
+	 * Destroys a queue and its objects using a cleanup function.
+	 *
+	 * If a queue and its contents should get destroyed using a specific
+	 * cleanup function, use destroy_function. This is useful when the
+	 * list contains malloc()-ed blocks which should get freed,
+	 * e.g.: queue->destroy_function(queue, free);
+	 *
+	 * @note No thread must wait in dequeue() when this function is called
+	 *
+	 * @param function	function to call on each object
+	 */
+	void (*destroy_function)(blocking_queue_t *this, void (*)(void*));
+
+};
+
+/**
+ * Creates an empty queue object.
+ *
+ * @return		blocking_queue_t object.
+ */
+blocking_queue_t *blocking_queue_create();
+
+#endif /** BLOCKING_QUEUE_H_ @}*/
+
diff --git a/src/libstrongswan/collections/enumerator.c b/src/libstrongswan/collections/enumerator.c
new file mode 100644
index 000000000..f80cdabd2
--- /dev/null
+++ b/src/libstrongswan/collections/enumerator.c
@@ -0,0 +1,560 @@
+/*
+ * Copyright (C) 2008 Tobias Brunner
+ * Copyright (C) 2007 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+#include "enumerator.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <limits.h>
+#include <stdio.h>
+#include <dirent.h>
+#include <errno.h>
+#include <string.h>
+
+#include <utils/debug.h>
+
+/**
+ * Implementation of enumerator_create_empty().enumerate
+ */
+static bool enumerate_empty(enumerator_t *enumerator, ...)
+{
+	return FALSE;
+}
+
+/**
+ * See header
+ */
+enumerator_t* enumerator_create_empty()
+{
+	enumerator_t *this = malloc_thing(enumerator_t);
+	this->enumerate = enumerate_empty;
+	this->destroy = (void*)free;
+	return this;
+}
+
+/**
+ * Enumerator implementation for directory enumerator
+ */
+typedef struct {
+	/** implements enumerator_t */
+	enumerator_t public;
+	/** directory handle */
+	DIR *dir;
+	/** absolute path of current file */
+	char full[PATH_MAX];
+	/** where directory part of full ends and relative file gets written */
+	char *full_end;
+} dir_enum_t;
+
+/**
+ * Implementation of enumerator_create_directory().destroy
+ */
+static void destroy_dir_enum(dir_enum_t *this)
+{
+	closedir(this->dir);
+	free(this);
+}
+
+/**
+ * Implementation of enumerator_create_directory().enumerate
+ */
+static bool enumerate_dir_enum(dir_enum_t *this, char **relative,
+							   char **absolute, struct stat *st)
+{
+	struct dirent *entry = readdir(this->dir);
+	size_t remaining;
+	int len;
+
+	if (!entry)
+	{
+		return FALSE;
+	}
+	if (streq(entry->d_name, ".") || streq(entry->d_name, ".."))
+	{
+		return enumerate_dir_enum(this, relative, absolute, st);
+	}
+	if (relative)
+	{
+		*relative = entry->d_name;
+	}
+	if (absolute || st)
+	{
+		remaining = sizeof(this->full) - (this->full_end - this->full);
+		len = snprintf(this->full_end, remaining, "%s", entry->d_name);
+		if (len < 0 || len >= remaining)
+		{
+			DBG1(DBG_LIB, "buffer too small to enumerate file '%s'",
+				 entry->d_name);
+			return FALSE;
+		}
+		if (absolute)
+		{
+			*absolute = this->full;
+		}
+		if (st)
+		{
+			if (stat(this->full, st))
+			{
+				DBG1(DBG_LIB, "stat() on '%s' failed: %s", this->full,
+					 strerror(errno));
+				return FALSE;
+			}
+		}
+	}
+	return TRUE;
+}
+
+/**
+ * See header
+ */
+enumerator_t* enumerator_create_directory(const char *path)
+{
+	int len;
+	dir_enum_t *this = malloc_thing(dir_enum_t);
+	this->public.enumerate = (void*)enumerate_dir_enum;
+	this->public.destroy = (void*)destroy_dir_enum;
+
+	if (*path == '\0')
+	{
+		path = "./";
+	}
+	len = snprintf(this->full, sizeof(this->full)-1, "%s", path);
+	if (len < 0 || len >= sizeof(this->full)-1)
+	{
+		DBG1(DBG_LIB, "path string '%s' too long", path);
+		free(this);
+		return NULL;
+	}
+	/* append a '/' if not already done */
+	if (this->full[len-1] != '/')
+	{
+		this->full[len++] = '/';
+		this->full[len] = '\0';
+	}
+	this->full_end = &this->full[len];
+
+	this->dir = opendir(path);
+	if (this->dir == NULL)
+	{
+		DBG1(DBG_LIB, "opening directory '%s' failed: %s", path, strerror(errno));
+		free(this);
+		return NULL;
+	}
+	return &this->public;
+}
+
+/**
+ * Enumerator implementation for directory enumerator
+ */
+typedef struct {
+	/** implements enumerator_t */
+	enumerator_t public;
+	/** string to parse */
+	char *string;
+	/** current position */
+	char *pos;
+	/** separater chars */
+	const char *sep;
+	/** trim chars */
+	const char *trim;
+} token_enum_t;
+
+/**
+ * Implementation of enumerator_create_token().destroy
+ */
+static void destroy_token_enum(token_enum_t *this)
+{
+	free(this->string);
+	free(this);
+}
+
+/**
+ * Implementation of enumerator_create_token().enumerate
+ */
+static bool enumerate_token_enum(token_enum_t *this, char **token)
+{
+	const char *sep, *trim;
+	char *pos = NULL, *tmp;
+	bool last = FALSE;
+
+	/* trim leading characters/separators */
+	while (*this->pos)
+	{
+		trim = this->trim;
+		while (*trim)
+		{
+			if (*trim == *this->pos)
+			{
+				this->pos++;
+				break;
+			}
+			trim++;
+		}
+		sep = this->sep;
+		while (*sep)
+		{
+			if (*sep == *this->pos)
+			{
+				this->pos++;
+				break;
+			}
+			sep++;
+		}
+		if (!*trim && !*sep)
+		{
+			break;
+		}
+	}
+
+	switch (*this->pos)
+	{
+		case '"':
+		case '\'':
+		{
+			/* read quoted token */
+			tmp = strchr(this->pos + 1, *this->pos);
+			if (tmp)
+			{
+				*token = this->pos + 1;
+				*tmp = '\0';
+				this->pos = tmp + 1;
+				return TRUE;
+			}
+			/* unterminated string, FALL-THROUGH */
+		}
+		default:
+		{
+			/* find nearest separator */
+			sep = this->sep;
+			while (*sep)
+			{
+				tmp = strchr(this->pos, *sep);
+				if (tmp && (pos == NULL || tmp < pos))
+				{
+					pos = tmp;
+				}
+				sep++;
+			}
+			*token = this->pos;
+			if (pos)
+			{
+				*pos = '\0';
+				this->pos = pos + 1;
+			}
+			else
+			{
+				last = TRUE;
+				pos = this->pos = strchr(this->pos, '\0');
+			}
+			break;
+		}
+	}
+
+	/* trim trailing characters/separators */
+	pos--;
+	while (pos >= *token)
+	{
+		trim = this->trim;
+		while (*trim)
+		{
+			if (*trim == *pos)
+			{
+				*(pos--) = '\0';
+				break;
+			}
+			trim++;
+		}
+		sep = this->sep;
+		while (*sep)
+		{
+			if (*sep == *pos)
+			{
+				*(pos--) = '\0';
+				break;
+			}
+			sep++;
+		}
+		if (!*trim && !*sep)
+		{
+			break;
+		}
+	}
+
+	if (!last || pos >= *token)
+	{
+		return TRUE;
+	}
+	return FALSE;
+}
+
+/**
+ * See header
+ */
+enumerator_t* enumerator_create_token(const char *string, const char *sep,
+									  const char *trim)
+{
+	token_enum_t *enumerator = malloc_thing(token_enum_t);
+
+	enumerator->public.enumerate = (void*)enumerate_token_enum;
+	enumerator->public.destroy = (void*)destroy_token_enum;
+	enumerator->string = strdup(string);
+	enumerator->pos = enumerator->string;
+	enumerator->sep = sep;
+	enumerator->trim = trim;
+
+	return &enumerator->public;
+}
+
+/**
+ * enumerator for nested enumerations
+ */
+typedef struct {
+	/* implements enumerator_t */
+	enumerator_t public;
+	/* outer enumerator */
+	enumerator_t *outer;
+	/* inner enumerator */
+	enumerator_t *inner;
+	/* constructor for inner enumerator */
+	enumerator_t *(*create_inner)(void *outer, void *data);
+	/* data to pass to constructor above */
+	void *data;
+	/* destructor for data */
+	void (*destroy_data)(void *data);
+} nested_enumerator_t;
+
+
+/**
+ * Implementation of enumerator_create_nested().enumerate()
+ */
+static bool enumerate_nested(nested_enumerator_t *this, void *v1, void *v2,
+							 void *v3, void *v4, void *v5)
+{
+	while (TRUE)
+	{
+		while (this->inner == NULL)
+		{
+			void *outer;
+
+			if (!this->outer->enumerate(this->outer, &outer))
+			{
+				return FALSE;
+			}
+			this->inner = this->create_inner(outer, this->data);
+		}
+		if (this->inner->enumerate(this->inner, v1, v2, v3, v4, v5))
+		{
+			return TRUE;
+		}
+		this->inner->destroy(this->inner);
+		this->inner = NULL;
+	}
+}
+
+/**
+ * Implementation of enumerator_create_nested().destroy()
+ **/
+static void destroy_nested(nested_enumerator_t *this)
+{
+	if (this->destroy_data)
+	{
+		this->destroy_data(this->data);
+	}
+	DESTROY_IF(this->inner);
+	this->outer->destroy(this->outer);
+	free(this);
+}
+
+/**
+ * See header
+ */
+enumerator_t *enumerator_create_nested(enumerator_t *outer,
+					enumerator_t *(inner_constructor)(void *outer, void *data),
+					void *data, void (*destroy_data)(void *data))
+{
+	nested_enumerator_t *enumerator = malloc_thing(nested_enumerator_t);
+
+	enumerator->public.enumerate = (void*)enumerate_nested;
+	enumerator->public.destroy = (void*)destroy_nested;
+	enumerator->outer = outer;
+	enumerator->inner = NULL;
+	enumerator->create_inner = (void*)inner_constructor;
+	enumerator->data = data;
+	enumerator->destroy_data = destroy_data;
+
+	return &enumerator->public;
+}
+
+/**
+ * enumerator for filtered enumerator
+ */
+typedef struct {
+	enumerator_t public;
+	enumerator_t *unfiltered;
+	void *data;
+	bool (*filter)(void *data, ...);
+	void (*destructor)(void *data);
+} filter_enumerator_t;
+
+/**
+ * Implementation of enumerator_create_filter().destroy
+ */
+static void destroy_filter(filter_enumerator_t *this)
+{
+	if (this->destructor)
+	{
+		this->destructor(this->data);
+	}
+	this->unfiltered->destroy(this->unfiltered);
+	free(this);
+}
+
+/**
+ * Implementation of enumerator_create_filter().enumerate
+ */
+static bool enumerate_filter(filter_enumerator_t *this, void *o1, void *o2,
+							 void *o3, void *o4, void *o5)
+{
+	void *i1, *i2, *i3, *i4, *i5;
+
+	while (this->unfiltered->enumerate(this->unfiltered, &i1, &i2, &i3, &i4, &i5))
+	{
+		if (this->filter(this->data, &i1, o1, &i2, o2, &i3, o3, &i4, o4, &i5, o5))
+		{
+			return TRUE;
+		}
+	}
+	return FALSE;
+}
+
+/**
+ * see header
+ */
+enumerator_t *enumerator_create_filter(enumerator_t *unfiltered,
+									   bool (*filter)(void *data, ...),
+									   void *data, void (*destructor)(void *data))
+{
+	filter_enumerator_t *this = malloc_thing(filter_enumerator_t);
+
+	this->public.enumerate = (void*)enumerate_filter;
+	this->public.destroy = (void*)destroy_filter;
+	this->unfiltered = unfiltered;
+	this->filter = filter;
+	this->data = data;
+	this->destructor = destructor;
+
+	return &this->public;
+}
+
+/**
+ * enumerator for cleaner enumerator
+ */
+typedef struct {
+	enumerator_t public;
+	enumerator_t *wrapped;
+	void (*cleanup)(void *data);
+	void *data;
+} cleaner_enumerator_t;
+
+/**
+ * Implementation of enumerator_create_cleanup().destroy
+ */
+static void destroy_cleaner(cleaner_enumerator_t *this)
+{
+	this->cleanup(this->data);
+	this->wrapped->destroy(this->wrapped);
+	free(this);
+}
+
+/**
+ * Implementation of enumerator_create_cleaner().enumerate
+ */
+static bool enumerate_cleaner(cleaner_enumerator_t *this, void *v1, void *v2,
+							  void *v3, void *v4, void *v5)
+{
+	return this->wrapped->enumerate(this->wrapped, v1, v2, v3, v4, v5);
+}
+
+/**
+ * see header
+ */
+enumerator_t *enumerator_create_cleaner(enumerator_t *wrapped,
+										void (*cleanup)(void *data), void *data)
+{
+	cleaner_enumerator_t *this = malloc_thing(cleaner_enumerator_t);
+
+	this->public.enumerate = (void*)enumerate_cleaner;
+	this->public.destroy = (void*)destroy_cleaner;
+	this->wrapped = wrapped;
+	this->cleanup = cleanup;
+	this->data = data;
+
+	return &this->public;
+}
+
+/**
+ * enumerator for single enumerator
+ */
+typedef struct {
+	enumerator_t public;
+	void *item;
+	void (*cleanup)(void *item);
+	bool done;
+} single_enumerator_t;
+
+/**
+ * Implementation of enumerator_create_single().destroy
+ */
+static void destroy_single(single_enumerator_t *this)
+{
+	if (this->cleanup)
+	{
+		this->cleanup(this->item);
+	}
+	free(this);
+}
+
+/**
+ * Implementation of enumerator_create_single().enumerate
+ */
+static bool enumerate_single(single_enumerator_t *this, void **item)
+{
+	if (this->done)
+	{
+		return FALSE;
+	}
+	*item = this->item;
+	this->done = TRUE;
+	return TRUE;
+}
+
+/**
+ * see header
+ */
+enumerator_t *enumerator_create_single(void *item, void (*cleanup)(void *item))
+{
+	single_enumerator_t *this = malloc_thing(single_enumerator_t);
+
+	this->public.enumerate = (void*)enumerate_single;
+	this->public.destroy = (void*)destroy_single;
+	this->item = item;
+	this->cleanup = cleanup;
+	this->done = FALSE;
+
+	return &this->public;
+}
+
diff --git a/src/libstrongswan/collections/enumerator.h b/src/libstrongswan/collections/enumerator.h
new file mode 100644
index 000000000..299373a3e
--- /dev/null
+++ b/src/libstrongswan/collections/enumerator.h
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2007 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup enumerator enumerator
+ * @{ @ingroup collections
+ */
+
+#ifndef ENUMERATOR_H_
+#define ENUMERATOR_H_
+
+typedef struct enumerator_t enumerator_t;
+
+#include <utils/utils.h>
+
+/**
+ * Enumerator interface, allows enumeration over collections.
+ */
+struct enumerator_t {
+
+	/**
+	 * Enumerate collection.
+	 *
+	 * The enumerate function takes a variable argument list containing
+	 * pointers where the enumerated values get written.
+	 *
+	 * @param ...	variable list of enumerated items, implementation dependent
+	 * @return		TRUE if pointers returned
+	 */
+	bool (*enumerate)(enumerator_t *this, ...);
+
+	/**
+	 * Destroy a enumerator instance.
+	 */
+	void (*destroy)(enumerator_t *this);
+};
+
+/**
+ * Create an enumerator which enumerates over nothing
+ *
+ * @return			an enumerator over no values
+ */
+enumerator_t* enumerator_create_empty();
+
+/**
+ * Create an enumerator which enumerates over a single item
+ *
+ * @param item		item to enumerate
+ * @param cleanup	cleanup function called on destroy with the item
+ * @return			an enumerator over a single value
+ */
+enumerator_t *enumerator_create_single(void *item, void (*cleanup)(void *item));
+
+/**
+ * Create an enumerator over files/subdirectories in a directory.
+ *
+ * This enumerator_t.enumerate() function returns a (to the directory) relative
+ * filename (as a char*), an absolute filename (as a char*) and a file status
+ * (to a struct stat), which all may be NULL. "." and ".." entries are
+ * skipped. Example:
+ *
+ * @code
+	char *rel, *abs;
+	struct stat st;
+	enumerator_t *e;
+
+	e = enumerator_create_directory("/tmp");
+	if (e)
+	{
+		while (e->enumerate(e, &rel, &abs, &st))
+		{
+			if (S_ISDIR(st.st_mode) && *rel != '.')
+			{
+				printf("%s\n", abs);
+			}
+		}
+		e->destroy(e);
+	}
+   @endcode
+ *
+ * @param path		path of the directory
+ * @return 			the directory enumerator, NULL on failure
+ */
+enumerator_t* enumerator_create_directory(const char *path);
+
+/**
+ * Create an enumerator over tokens of a string.
+ *
+ * Tokens are separated by one of the characters in sep and trimmed by the
+ * characters in trim.
+ *
+ * @param string	string to parse
+ * @param sep		separator characters
+ * @param trim		characters to trim from tokens
+ * @return			enumerator over char* tokens
+ */
+enumerator_t* enumerator_create_token(const char *string, const char *sep,
+									  const char *trim);
+
+/**
+ * Creates an enumerator which enumerates over enumerated enumerators :-).
+ *
+ * The variable argument list of enumeration values is limit to 5.
+ *
+ * @param outer					outer enumerator
+ * @param inner_constructor		constructor to inner enumerator
+ * @param data					data to pass to each inner_constructor call
+ * @param destroy_data			destructor to pass to data
+ * @return						the nested enumerator
+ */
+enumerator_t *enumerator_create_nested(enumerator_t *outer,
+					enumerator_t *(*inner_constructor)(void *outer, void *data),
+					void *data, void (*destroy_data)(void *data));
+
+/**
+ * Creates an enumerator which filters output of another enumerator.
+ *
+ * The filter function receives the user supplied "data" followed by a
+ * unfiltered enumeration item, followed by an output pointer where to write
+ * the filtered data. Then the next input/output pair follows.
+ * It returns TRUE to deliver the
+ * values to the caller of enumerate(), FALSE to filter this enumeration.
+ *
+ * The variable argument list of enumeration values is limit to 5.
+ *
+ * @param unfiltered			unfiltered enumerator to wrap, gets destroyed
+ * @param filter				filter function
+ * @param data					user data to supply to filter
+ * @param destructor			destructor function to clean up data after use
+ * @return						the filtered enumerator
+ */
+enumerator_t *enumerator_create_filter(enumerator_t *unfiltered,
+					bool (*filter)(void *data, ...),
+					void *data, void (*destructor)(void *data));
+
+/**
+ * Create an enumerator wrapper which does a cleanup on destroy.
+ *
+ * @param wrapped				wrapped enumerator
+ * @param cleanup				cleanup function called on destroy
+ * @param data					user data to supply to cleanup
+ * @return						the enumerator with cleanup
+ */
+enumerator_t *enumerator_create_cleaner(enumerator_t *wrapped,
+					void (*cleanup)(void *data), void *data);
+
+#endif /** ENUMERATOR_H_ @}*/
diff --git a/src/libstrongswan/collections/hashtable.c b/src/libstrongswan/collections/hashtable.c
new file mode 100644
index 000000000..d181d8ec8
--- /dev/null
+++ b/src/libstrongswan/collections/hashtable.c
@@ -0,0 +1,444 @@
+/*
+ * Copyright (C) 2008-2012 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+
+#include "hashtable.h"
+
+/** The maximum capacity of the hash table (MUST be a power of 2) */
+#define MAX_CAPACITY (1 << 30)
+
+typedef struct pair_t pair_t;
+
+/**
+ * This pair holds a pointer to the key and value it represents.
+ */
+struct pair_t {
+	/**
+	 * Key of a hash table item.
+	 */
+	void *key;
+
+	/**
+	 * Value of a hash table item.
+	 */
+	void *value;
+
+	/**
+	 * Cached hash (used in case of a resize).
+	 */
+	u_int hash;
+
+	/**
+	 * Next pair in an overflow list.
+	 */
+	pair_t *next;
+};
+
+/**
+ * Creates an empty pair object.
+ */
+static inline pair_t *pair_create(void *key, void *value, u_int hash)
+{
+	pair_t *this;
+
+	INIT(this,
+		.key = key,
+		.value = value,
+		.hash = hash,
+	);
+
+	return this;
+}
+
+typedef struct private_hashtable_t private_hashtable_t;
+
+/**
+ * Private data of a hashtable_t object.
+ *
+ */
+struct private_hashtable_t {
+	/**
+	 * Public part of hash table.
+	 */
+	hashtable_t public;
+
+	/**
+	 * The number of items in the hash table.
+	 */
+	u_int count;
+
+	/**
+	 * The current capacity of the hash table (always a power of 2).
+	 */
+	u_int capacity;
+
+	/**
+	 * The current mask to calculate the row index (capacity - 1).
+	 */
+	u_int mask;
+
+	/**
+	 * The load factor.
+	 */
+	float load_factor;
+
+	/**
+	 * The actual table.
+	 */
+	pair_t **table;
+
+	/**
+	 * The hashing function.
+	 */
+	hashtable_hash_t hash;
+
+	/**
+	 * The equality function.
+	 */
+	hashtable_equals_t equals;
+};
+
+typedef struct private_enumerator_t private_enumerator_t;
+
+/**
+ * hash table enumerator implementation
+ */
+struct private_enumerator_t {
+
+	/**
+	 * implements enumerator interface
+	 */
+	enumerator_t enumerator;
+
+	/**
+	 * associated hash table
+	 */
+	private_hashtable_t *table;
+
+	/**
+	 * current row index
+	 */
+	u_int row;
+
+	/**
+	 * number of remaining items in hashtable
+	 */
+	u_int count;
+
+	/**
+	 * current pair
+	 */
+	pair_t *current;
+
+	/**
+	 * previous pair (used by remove_at)
+	 */
+	pair_t *prev;
+
+};
+
+/**
+ * This function returns the next-highest power of two for the given number.
+ * The algorithm works by setting all bits on the right-hand side of the most
+ * significant 1 to 1 and then increments the whole number so it rolls over
+ * to the nearest power of two. Note: returns 0 for n == 0
+ */
+static u_int get_nearest_powerof2(u_int n)
+{
+	u_int i;
+
+	--n;
+	for (i = 1; i < sizeof(u_int) * 8; i <<= 1)
+	{
+		n |= n >> i;
+	}
+	return ++n;
+}
+
+/**
+ * Init hash table parameters
+ */
+static void init_hashtable(private_hashtable_t *this, u_int capacity)
+{
+	capacity = max(1, min(capacity, MAX_CAPACITY));
+	this->capacity = get_nearest_powerof2(capacity);
+	this->mask = this->capacity - 1;
+	this->load_factor = 0.75;
+
+	this->table = calloc(this->capacity, sizeof(pair_t*));
+}
+
+/**
+ * Double the size of the hash table and rehash all the elements.
+ */
+static void rehash(private_hashtable_t *this)
+{
+	pair_t **old_table;
+	u_int row, old_capacity;
+
+	if (this->capacity >= MAX_CAPACITY)
+	{
+		return;
+	}
+
+	old_capacity = this->capacity;
+	old_table = this->table;
+
+	init_hashtable(this, old_capacity << 1);
+
+	for (row = 0; row < old_capacity; row++)
+	{
+		pair_t *pair, *next;
+		u_int new_row;
+
+		pair = old_table[row];
+		while (pair)
+		{	/* insert pair at the front of new bucket*/
+			next = pair->next;
+			new_row = pair->hash & this->mask;
+			pair->next = this->table[new_row];
+			this->table[new_row] = pair;
+			pair = next;
+		}
+	}
+	free(old_table);
+}
+
+METHOD(hashtable_t, put, void*,
+	   private_hashtable_t *this, void *key, void *value)
+{
+	void *old_value = NULL;
+	pair_t *pair;
+	u_int hash, row;
+
+	hash = this->hash(key);
+	row = hash & this->mask;
+	pair = this->table[row];
+	while (pair)
+	{	/* search existing bucket for key */
+		if (this->equals(key, pair->key))
+		{
+			old_value = pair->value;
+			pair->value = value;
+			pair->key = key;
+			break;
+		}
+		pair = pair->next;
+	}
+	if (!pair)
+	{	/* insert at the front of bucket */
+		pair = pair_create(key, value, hash);
+		pair->next = this->table[row];
+		this->table[row] = pair;
+		this->count++;
+	}
+	if (this->count >= this->capacity * this->load_factor)
+	{
+		rehash(this);
+	}
+	return old_value;
+}
+
+static void *get_internal(private_hashtable_t *this, void *key,
+						  hashtable_equals_t equals)
+{
+	void *value = NULL;
+	pair_t *pair;
+
+	if (!this->count)
+	{	/* no need to calculate the hash */
+		return NULL;
+	}
+
+	pair = this->table[this->hash(key) & this->mask];
+	while (pair)
+	{
+		if (equals(key, pair->key))
+		{
+			value = pair->value;
+			break;
+		}
+		pair = pair->next;
+	}
+	return value;
+}
+
+METHOD(hashtable_t, get, void*,
+	   private_hashtable_t *this, void *key)
+{
+	return get_internal(this, key, this->equals);
+}
+
+METHOD(hashtable_t, get_match, void*,
+	   private_hashtable_t *this, void *key, hashtable_equals_t match)
+{
+	return get_internal(this, key, match);
+}
+
+METHOD(hashtable_t, remove_, void*,
+	   private_hashtable_t *this, void *key)
+{
+	void *value = NULL;
+	pair_t *pair, *prev = NULL;
+	u_int row;
+
+	row = this->hash(key) & this->mask;
+	pair = this->table[row];
+	while (pair)
+	{
+		if (this->equals(key, pair->key))
+		{
+			if (prev)
+			{
+				prev->next = pair->next;
+			}
+			else
+			{
+				this->table[row] = pair->next;
+			}
+			value = pair->value;
+			this->count--;
+			free(pair);
+			break;
+		}
+		prev = pair;
+		pair = pair->next;
+	}
+	return value;
+}
+
+METHOD(hashtable_t, remove_at, void,
+	   private_hashtable_t *this, private_enumerator_t *enumerator)
+{
+	if (enumerator->table == this && enumerator->current)
+	{
+		pair_t *current = enumerator->current;
+		if (enumerator->prev)
+		{
+			enumerator->prev->next = current->next;
+		}
+		else
+		{
+			this->table[enumerator->row] = current->next;
+		}
+		enumerator->current = enumerator->prev;
+		free(current);
+		this->count--;
+	}
+}
+
+METHOD(hashtable_t, get_count, u_int,
+	   private_hashtable_t *this)
+{
+	return this->count;
+}
+
+METHOD(enumerator_t, enumerate, bool,
+	   private_enumerator_t *this, void **key, void **value)
+{
+	while (this->count && this->row < this->table->capacity)
+	{
+		this->prev = this->current;
+		if (this->current)
+		{
+			this->current = this->current->next;
+		}
+		else
+		{
+			this->current = this->table->table[this->row];
+		}
+		if (this->current)
+		{
+			if (key)
+			{
+				*key = this->current->key;
+			}
+			if (value)
+			{
+				*value = this->current->value;
+			}
+			this->count--;
+			return TRUE;
+		}
+		this->row++;
+	}
+	return FALSE;
+}
+
+METHOD(hashtable_t, create_enumerator, enumerator_t*,
+	   private_hashtable_t *this)
+{
+	private_enumerator_t *enumerator;
+
+	INIT(enumerator,
+		.enumerator = {
+			.enumerate = (void*)_enumerate,
+			.destroy = (void*)free,
+		},
+		.table = this,
+		.count = this->count,
+	);
+
+	return &enumerator->enumerator;
+}
+
+METHOD(hashtable_t, destroy, void,
+	   private_hashtable_t *this)
+{
+	pair_t *pair, *next;
+	u_int row;
+
+	for (row = 0; row < this->capacity; row++)
+	{
+		pair = this->table[row];
+		while (pair)
+		{
+			next = pair->next;
+			free(pair);
+			pair = next;
+		}
+	}
+	free(this->table);
+	free(this);
+}
+
+/*
+ * Described in header.
+ */
+hashtable_t *hashtable_create(hashtable_hash_t hash, hashtable_equals_t equals,
+							  u_int capacity)
+{
+	private_hashtable_t *this;
+
+	INIT(this,
+		.public = {
+			.put = _put,
+			.get = _get,
+			.get_match = _get_match,
+			.remove = _remove_,
+			.remove_at = (void*)_remove_at,
+			.get_count = _get_count,
+			.create_enumerator = _create_enumerator,
+			.destroy = _destroy,
+		},
+		.hash = hash,
+		.equals = equals,
+	);
+
+	init_hashtable(this, capacity);
+
+	return &this->public;
+}
+
diff --git a/src/libstrongswan/collections/hashtable.h b/src/libstrongswan/collections/hashtable.h
new file mode 100644
index 000000000..e38850ded
--- /dev/null
+++ b/src/libstrongswan/collections/hashtable.h
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2008-2012 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup hashtable hashtable
+ * @{ @ingroup collections
+ */
+
+#ifndef HASHTABLE_H_
+#define HASHTABLE_H_
+
+#include <collections/enumerator.h>
+
+typedef struct hashtable_t hashtable_t;
+
+/**
+ * Prototype for a function that computes the hash code from the given key.
+ *
+ * @param key			key to hash
+ * @return				hash code
+ */
+typedef u_int (*hashtable_hash_t)(void *key);
+
+/**
+ * Prototype for a function that compares the two keys for equality.
+ *
+ * @param key			first key (the one we are looking for)
+ * @param other_key		second key
+ * @return				TRUE if the keys are equal
+ */
+typedef bool (*hashtable_equals_t)(void *key, void *other_key);
+
+/**
+ * Class implementing a hash table.
+ *
+ * General purpose hash table. This hash table is not synchronized.
+ */
+struct hashtable_t {
+
+	/**
+	 * Create an enumerator over the hash table key/value pairs.
+	 *
+	 * @return			enumerator over (void *key, void *value)
+	 */
+	enumerator_t *(*create_enumerator) (hashtable_t *this);
+
+	/**
+	 * Adds the given value with the given key to the hash table, if there
+	 * exists no entry with that key. NULL is returned in this case.
+	 * Otherwise the existing value is replaced and the function returns the
+	 * old value.
+	 *
+	 * @param key		the key to store
+	 * @param value		the value to store
+	 * @return			NULL if no item was replaced, the old value otherwise
+	 */
+	void *(*put) (hashtable_t *this, void *key, void *value);
+
+	/**
+	 * Returns the value with the given key, if the hash table contains such an
+	 * entry, otherwise NULL is returned.
+	 *
+	 * @param key		the key of the requested value
+	 * @return			the value, NULL if not found
+	 */
+	void *(*get) (hashtable_t *this, void *key);
+
+	/**
+	 * Returns the value with a matching key, if the hash table contains such an
+	 * entry, otherwise NULL is returned.
+	 *
+	 * Compared to get() the given match function is used to compare the keys
+	 * for equality.  The hash function does have to be deviced properly in
+	 * order to make this work if the match function compares keys differently
+	 * than the equals function provided to the constructor.  This basically
+	 * allows to enumerate all entries with the same hash value.
+	 *
+	 * @param key		the key to match against
+	 * @param match		match function to be used when comparing keys
+	 * @return			the value, NULL if not found
+	 */
+	void *(*get_match) (hashtable_t *this, void *key, hashtable_equals_t match);
+
+	/**
+	 * Removes the value with the given key from the hash table and returns the
+	 * removed value (or NULL if no such value existed).
+	 *
+	 * @param key		the key of the value to remove
+	 * @return			the removed value, NULL if not found
+	 */
+	void *(*remove) (hashtable_t *this, void *key);
+
+	/**
+	 * Removes the key and value pair from the hash table at which the given
+	 * enumerator currently points.
+	 *
+	 * @param enumerator	enumerator, from create_enumerator
+	 */
+	void (*remove_at) (hashtable_t *this, enumerator_t *enumerator);
+
+	/**
+	 * Gets the number of items in the hash table.
+	 *
+	 * @return			number of items
+	 */
+	u_int (*get_count) (hashtable_t *this);
+
+	/**
+	 * Destroys a hash table object.
+	 */
+	void (*destroy) (hashtable_t *this);
+
+};
+
+/**
+ * Creates an empty hash table object.
+ *
+ * @param hash			hash function
+ * @param equals		equals function
+ * @param capacity		initial capacity
+ * @return				hashtable_t object.
+ */
+hashtable_t *hashtable_create(hashtable_hash_t hash, hashtable_equals_t equals,
+							  u_int capacity);
+
+#endif /** HASHTABLE_H_ @}*/
diff --git a/src/libstrongswan/collections/linked_list.c b/src/libstrongswan/collections/linked_list.c
new file mode 100644
index 000000000..1ff80999b
--- /dev/null
+++ b/src/libstrongswan/collections/linked_list.c
@@ -0,0 +1,615 @@
+/*
+ * Copyright (C) 2007-2011 Tobias Brunner
+ * Copyright (C) 2005-2006 Martin Willi
+ * Copyright (C) 2005 Jan Hutter
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+#include <stdlib.h>
+#include <stdarg.h>
+
+#include "linked_list.h"
+
+typedef struct element_t element_t;
+
+/**
+ * This element holds a pointer to the value it represents.
+ */
+struct element_t {
+
+	/**
+	 * Value of a list item.
+	 */
+	void *value;
+
+	/**
+	 * Previous list element.
+	 *
+	 * NULL if first element in list.
+	 */
+	element_t *previous;
+
+	/**
+	 * Next list element.
+	 *
+	 * NULL if last element in list.
+	 */
+	element_t *next;
+};
+
+/**
+ * Creates an empty linked list object.
+ */
+element_t *element_create(void *value)
+{
+	element_t *this;
+	INIT(this,
+		.value = value,
+	);
+	return this;
+}
+
+
+typedef struct private_linked_list_t private_linked_list_t;
+
+/**
+ * Private data of a linked_list_t object.
+ *
+ */
+struct private_linked_list_t {
+	/**
+	 * Public part of linked list.
+	 */
+	linked_list_t public;
+
+	/**
+	 * Number of items in the list.
+	 */
+	int count;
+
+	/**
+	 * First element in list.
+	 * NULL if no elements in list.
+	 */
+	element_t *first;
+
+	/**
+	 * Last element in list.
+	 * NULL if no elements in list.
+	 */
+	element_t *last;
+};
+
+typedef struct private_enumerator_t private_enumerator_t;
+
+/**
+ * linked lists enumerator implementation
+ */
+struct private_enumerator_t {
+
+	/**
+	 * implements enumerator interface
+	 */
+	enumerator_t enumerator;
+
+	/**
+	 * associated linked list
+	 */
+	private_linked_list_t *list;
+
+	/**
+	 * current item
+	 */
+	element_t *current;
+
+	/**
+	 * enumerator has enumerated all items
+	 */
+	bool finished;
+};
+
+METHOD(enumerator_t, enumerate, bool,
+	private_enumerator_t *this, void **item)
+{
+	if (this->finished)
+	{
+		return FALSE;
+	}
+	if (!this->current)
+	{
+		this->current = this->list->first;
+	}
+	else
+	{
+		this->current = this->current->next;
+	}
+	if (!this->current)
+	{
+		this->finished = TRUE;
+		return FALSE;
+	}
+	*item = this->current->value;
+	return TRUE;
+}
+
+METHOD(linked_list_t, create_enumerator, enumerator_t*,
+	private_linked_list_t *this)
+{
+	private_enumerator_t *enumerator;
+
+	INIT(enumerator,
+		.enumerator = {
+			.enumerate = (void*)_enumerate,
+			.destroy = (void*)free,
+		},
+		.list = this,
+	);
+
+	return &enumerator->enumerator;
+}
+
+METHOD(linked_list_t, reset_enumerator, void,
+	private_linked_list_t *this, private_enumerator_t *enumerator)
+{
+	enumerator->current = NULL;
+	enumerator->finished = FALSE;
+}
+
+METHOD(linked_list_t, has_more, bool,
+	private_linked_list_t *this, private_enumerator_t *enumerator)
+{
+	if (enumerator->current)
+	{
+		return enumerator->current->next != NULL;
+	}
+	return !enumerator->finished && this->first != NULL;
+}
+
+METHOD(linked_list_t, get_count, int,
+	private_linked_list_t *this)
+{
+	return this->count;
+}
+
+METHOD(linked_list_t, insert_first, void,
+	private_linked_list_t *this, void *item)
+{
+	element_t *element;
+
+	element = element_create(item);
+	if (this->count == 0)
+	{
+		/* first entry in list */
+		this->first = element;
+		this->last = element;
+	}
+	else
+	{
+		element->next = this->first;
+		this->first->previous = element;
+		this->first = element;
+	}
+	this->count++;
+}
+
+/**
+ * unlink an element form the list, returns following element
+ */
+static element_t* remove_element(private_linked_list_t *this,
+								 element_t *element)
+{
+	element_t *next, *previous;
+
+	next = element->next;
+	previous = element->previous;
+	free(element);
+	if (next)
+	{
+		next->previous = previous;
+	}
+	else
+	{
+		this->last = previous;
+	}
+	if (previous)
+	{
+		previous->next = next;
+	}
+	else
+	{
+		this->first = next;
+	}
+	if (--this->count == 0)
+	{
+		this->first = NULL;
+		this->last = NULL;
+	}
+	return next;
+}
+
+METHOD(linked_list_t, get_first, status_t,
+	private_linked_list_t *this, void **item)
+{
+	if (this->count == 0)
+	{
+		return NOT_FOUND;
+	}
+	*item = this->first->value;
+	return SUCCESS;
+}
+
+METHOD(linked_list_t, remove_first, status_t,
+	private_linked_list_t *this, void **item)
+{
+	if (get_first(this, item) == SUCCESS)
+	{
+		remove_element(this, this->first);
+		return SUCCESS;
+	}
+	return NOT_FOUND;
+}
+
+METHOD(linked_list_t, insert_last, void,
+	private_linked_list_t *this, void *item)
+{
+	element_t *element;
+
+	element = element_create(item);
+	if (this->count == 0)
+	{
+		/* first entry in list */
+		this->first = element;
+		this->last = element;
+	}
+	else
+	{
+		element->previous = this->last;
+		this->last->next = element;
+		this->last = element;
+	}
+	this->count++;
+}
+
+METHOD(linked_list_t, insert_before, void,
+	private_linked_list_t *this, private_enumerator_t *enumerator,
+	void *item)
+{
+	element_t *current, *element;
+
+	current = enumerator->current;
+	if (!current)
+	{
+		if (enumerator->finished)
+		{
+			this->public.insert_last(&this->public, item);
+		}
+		else
+		{
+			this->public.insert_first(&this->public, item);
+		}
+		return;
+	}
+	element = element_create(item);
+	if (current->previous)
+	{
+		current->previous->next = element;
+		element->previous = current->previous;
+		current->previous = element;
+		element->next = current;
+	}
+	else
+	{
+		current->previous = element;
+		element->next = current;
+		this->first = element;
+	}
+	this->count++;
+}
+
+METHOD(linked_list_t, replace, void*,
+	private_linked_list_t *this, private_enumerator_t *enumerator,
+	void *item)
+{
+	void *old = NULL;
+
+	if (enumerator->current)
+	{
+		old = enumerator->current->value;
+		enumerator->current->value = item;
+	}
+	return old;
+}
+
+METHOD(linked_list_t, get_last, status_t,
+	private_linked_list_t *this, void **item)
+{
+	if (this->count == 0)
+	{
+		return NOT_FOUND;
+	}
+	*item = this->last->value;
+	return SUCCESS;
+}
+
+METHOD(linked_list_t, remove_last, status_t,
+	private_linked_list_t *this, void **item)
+{
+	if (get_last(this, item) == SUCCESS)
+	{
+		remove_element(this, this->last);
+		return SUCCESS;
+	}
+	return NOT_FOUND;
+}
+
+METHOD(linked_list_t, remove_, int,
+	private_linked_list_t *this, void *item, bool (*compare)(void*,void*))
+{
+	element_t *current = this->first;
+	int removed = 0;
+
+	while (current)
+	{
+		if ((compare && compare(current->value, item)) ||
+			(!compare && current->value == item))
+		{
+			removed++;
+			current = remove_element(this, current);
+		}
+		else
+		{
+			current = current->next;
+		}
+	}
+	return removed;
+}
+
+METHOD(linked_list_t, remove_at, void,
+	   private_linked_list_t *this, private_enumerator_t *enumerator)
+{
+	element_t *current;
+
+	if (enumerator->current)
+	{
+		current = enumerator->current;
+		enumerator->current = current->previous;
+		remove_element(this, current);
+	}
+}
+
+METHOD(linked_list_t, find_first, status_t,
+	private_linked_list_t *this, linked_list_match_t match,
+	void **item, void *d1, void *d2, void *d3, void *d4, void *d5)
+{
+	element_t *current = this->first;
+
+	while (current)
+	{
+		if ((match && match(current->value, d1, d2, d3, d4, d5)) ||
+			(!match && item && current->value == *item))
+		{
+			if (item != NULL)
+			{
+				*item = current->value;
+			}
+			return SUCCESS;
+		}
+		current = current->next;
+	}
+	return NOT_FOUND;
+}
+
+METHOD(linked_list_t, find_last, status_t,
+	private_linked_list_t *this, linked_list_match_t match,
+	void **item, void *d1, void *d2, void *d3, void *d4, void *d5)
+{
+	element_t *current = this->last;
+
+	while (current)
+	{
+		if ((match && match(current->value, d1, d2, d3, d4, d5)) ||
+			(!match && item && current->value == *item))
+		{
+			if (item != NULL)
+			{
+				*item = current->value;
+			}
+			return SUCCESS;
+		}
+		current = current->previous;
+	}
+	return NOT_FOUND;
+}
+
+METHOD(linked_list_t, invoke_offset, void,
+	private_linked_list_t *this, size_t offset,
+	void *d1, void *d2, void *d3, void *d4, void *d5)
+{
+	element_t *current = this->first;
+	linked_list_invoke_t *method;
+
+	while (current)
+	{
+		method = current->value + offset;
+		(*method)(current->value, d1, d2, d3, d4, d5);
+		current = current->next;
+	}
+}
+
+METHOD(linked_list_t, invoke_function, void,
+	private_linked_list_t *this, linked_list_invoke_t fn,
+	void *d1, void *d2, void *d3, void *d4, void *d5)
+{
+	element_t *current = this->first;
+
+	while (current)
+	{
+		fn(current->value, d1, d2, d3, d4, d5);
+		current = current->next;
+	}
+}
+
+METHOD(linked_list_t, clone_offset, linked_list_t*,
+	private_linked_list_t *this, size_t offset)
+{
+	element_t *current = this->first;
+	linked_list_t *clone;
+
+	clone = linked_list_create();
+	while (current)
+	{
+		void* (**method)(void*) = current->value + offset;
+		clone->insert_last(clone, (*method)(current->value));
+		current = current->next;
+	}
+
+	return clone;
+}
+
+METHOD(linked_list_t, clone_function, linked_list_t*,
+	private_linked_list_t *this, void* (*fn)(void*))
+{
+	element_t *current = this->first;
+	linked_list_t *clone;
+
+	clone = linked_list_create();
+	while (current)
+	{
+		clone->insert_last(clone, fn(current->value));
+		current = current->next;
+	}
+	return clone;
+}
+
+METHOD(linked_list_t, destroy, void,
+	private_linked_list_t *this)
+{
+	void *value;
+
+	/* Remove all list items before destroying list */
+	while (remove_first(this, &value) == SUCCESS)
+	{
+		/* values are not destroyed so memory leaks are possible
+		 * if list is not empty when deleting */
+	}
+	free(this);
+}
+
+METHOD(linked_list_t, destroy_offset, void,
+	private_linked_list_t *this, size_t offset)
+{
+	element_t *current = this->first, *next;
+
+	while (current)
+	{
+		void (**method)(void*) = current->value + offset;
+		(*method)(current->value);
+		next = current->next;
+		free(current);
+		current = next;
+	}
+	free(this);
+}
+
+METHOD(linked_list_t, destroy_function, void,
+	private_linked_list_t *this, void (*fn)(void*))
+{
+	element_t *current = this->first, *next;
+
+	while (current)
+	{
+		fn(current->value);
+		next = current->next;
+		free(current);
+		current = next;
+	}
+	free(this);
+}
+
+/*
+ * Described in header.
+ */
+linked_list_t *linked_list_create()
+{
+	private_linked_list_t *this;
+
+	INIT(this,
+		.public = {
+			.get_count = _get_count,
+			.create_enumerator = _create_enumerator,
+			.reset_enumerator = (void*)_reset_enumerator,
+			.has_more = (void*)_has_more,
+			.get_first = _get_first,
+			.get_last = _get_last,
+			.find_first = (void*)_find_first,
+			.find_last = (void*)_find_last,
+			.insert_first = _insert_first,
+			.insert_last = _insert_last,
+			.insert_before = (void*)_insert_before,
+			.replace = (void*)_replace,
+			.remove_first = _remove_first,
+			.remove_last = _remove_last,
+			.remove = _remove_,
+			.remove_at = (void*)_remove_at,
+			.invoke_offset = (void*)_invoke_offset,
+			.invoke_function = (void*)_invoke_function,
+			.clone_offset = _clone_offset,
+			.clone_function = _clone_function,
+			.destroy = _destroy,
+			.destroy_offset = _destroy_offset,
+			.destroy_function = _destroy_function,
+		},
+	);
+
+	return &this->public;
+}
+
+/*
+ * See header.
+ */
+linked_list_t *linked_list_create_from_enumerator(enumerator_t *enumerator)
+{
+	linked_list_t *list;
+	void *item;
+
+	list = linked_list_create();
+
+	while (enumerator->enumerate(enumerator, &item))
+	{
+		list->insert_last(list, item);
+	}
+	enumerator->destroy(enumerator);
+
+	return list;
+}
+
+/*
+ * See header.
+ */
+linked_list_t *linked_list_create_with_items(void *item, ...)
+{
+	linked_list_t *list;
+	va_list args;
+
+	list = linked_list_create();
+
+	va_start(args, item);
+	while (item)
+	{
+		list->insert_last(list, item);
+		item = va_arg(args, void*);
+	}
+	va_end(args);
+
+	return list;
+}
diff --git a/src/libstrongswan/collections/linked_list.h b/src/libstrongswan/collections/linked_list.h
new file mode 100644
index 000000000..da539a231
--- /dev/null
+++ b/src/libstrongswan/collections/linked_list.h
@@ -0,0 +1,319 @@
+/*
+ * Copyright (C) 2007-2011 Tobias Brunner
+ * Copyright (C) 2005-2008 Martin Willi
+ * Copyright (C) 2005 Jan Hutter
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup linked_list linked_list
+ * @{ @ingroup collections
+ */
+
+#ifndef LINKED_LIST_H_
+#define LINKED_LIST_H_
+
+typedef struct linked_list_t linked_list_t;
+
+#include <collections/enumerator.h>
+
+/**
+ * Method to match elements in a linked list (used in find_* functions)
+ *
+ * @param item			current list item
+ * @param ...			user supplied data (only pointers, at most 5)
+ * @return
+ *						- TRUE, if the item matched
+ *						- FALSE, otherwise
+ */
+typedef bool (*linked_list_match_t)(void *item, ...);
+
+/**
+ * Method to be invoked on elements in a linked list (used in invoke_* functions)
+ *
+ * @param item			current list item
+ * @param ...			user supplied data (only pointers, at most 5)
+ */
+typedef void (*linked_list_invoke_t)(void *item, ...);
+
+/**
+ * Class implementing a double linked list.
+ *
+ * General purpose linked list. This list is not synchronized.
+ */
+struct linked_list_t {
+
+	/**
+	 * Gets the count of items in the list.
+	 *
+	 * @return			number of items in list
+	 */
+	int (*get_count) (linked_list_t *this);
+
+	/**
+	 * Create an enumerator over the list.
+	 *
+	 * @note The enumerator's position is invalid before the first call
+	 * to enumerate().
+	 *
+	 * @return			enumerator over list items
+	 */
+	enumerator_t* (*create_enumerator)(linked_list_t *this);
+
+	/**
+	 * Resets the enumerator's current position to the beginning of the list.
+	 *
+	 * @param enumerator	enumerator to reset
+	 */
+	void (*reset_enumerator)(linked_list_t *this, enumerator_t *enumerator);
+
+	/**
+	 * Checks if there are more elements following after the enumerator's
+	 * current position.
+	 *
+	 * @param enumerator	enumerator to check
+	 */
+	bool (*has_more)(linked_list_t *this, enumerator_t *enumerator);
+
+	/**
+	 * Inserts a new item at the beginning of the list.
+	 *
+	 * @param item		item value to insert in list
+	 */
+	void (*insert_first) (linked_list_t *this, void *item);
+
+	/**
+	 * Removes the first item in the list and returns its value.
+	 *
+	 * @param item		returned value of first item, or NULL
+	 * @return			SUCCESS, or NOT_FOUND if list is empty
+	 */
+	status_t (*remove_first) (linked_list_t *this, void **item);
+
+	/**
+	 * Inserts a new item before the item the enumerator currently points to.
+	 *
+	 * If this method is called before starting the enumeration the item is
+	 * inserted first. If it is called after all items have been enumerated
+	 * the item is inserted last. This is helpful when inserting items into
+	 * a sorted list.
+	 *
+	 * @note The position of the enumerator is not changed.
+	 *
+	 * @param enumerator	enumerator with position
+	 * @param item			item value to insert in list
+	 */
+	void (*insert_before)(linked_list_t *this, enumerator_t *enumerator,
+						  void *item);
+
+	/**
+	 * Replaces the item the enumerator currently points to with the given item.
+	 *
+	 * @param enumerator	enumerator with position
+	 * @param item			item value to replace current item with
+	 * @return				current item or NULL if the enumerator is at an
+	 *						invalid position
+	 */
+	void *(*replace)(linked_list_t *this, enumerator_t *enumerator, void *item);
+
+	/**
+	 * Remove an item from the list where the enumerator points to.
+	 *
+	 * @param enumerator enumerator with position
+	 */
+	void (*remove_at)(linked_list_t *this, enumerator_t *enumerator);
+
+	/**
+	 * Remove items from the list matching the given item.
+	 *
+	 * If a compare function is given, it is called for each item, with the
+	 * first parameter being the current list item and the second parameter
+	 * being the supplied item. Return TRUE from the compare function to remove
+	 * the item, return FALSE to keep it in the list.
+	 *
+	 * If compare is NULL, comparison is done by pointers.
+	 *
+	 * @param item		item to remove/pass to comparator
+	 * @param compare	compare function, or NULL
+	 * @return			number of removed items
+	 */
+	int (*remove)(linked_list_t *this, void *item, bool (*compare)(void*,void*));
+
+	/**
+	 * Returns the value of the first list item without removing it.
+	 *
+	 * @param item		returned value of first item
+	 * @return			SUCCESS, NOT_FOUND if list is empty
+	 */
+	status_t (*get_first) (linked_list_t *this, void **item);
+
+	/**
+	 * Inserts a new item at the end of the list.
+	 *
+	 * @param item		value to insert into list
+	 */
+	void (*insert_last) (linked_list_t *this, void *item);
+
+	/**
+	 * Removes the last item in the list and returns its value.
+	 *
+	 * @param item		returned value of last item, or NULL
+	 * @return			SUCCESS, NOT_FOUND if list is empty
+	 */
+	status_t (*remove_last) (linked_list_t *this, void **item);
+
+	/**
+	 * Returns the value of the last list item without removing it.
+	 *
+	 * @param item		returned value of last item
+	 * @return			SUCCESS, NOT_FOUND if list is empty
+	 */
+	status_t (*get_last) (linked_list_t *this, void **item);
+
+	/** Find the first matching element in the list.
+	 *
+	 * The first object passed to the match function is the current list item,
+	 * followed by the user supplied data.
+	 * If the supplied function returns TRUE this function returns SUCCESS, and
+	 * the current object is returned in the third parameter, otherwise,
+	 * the next item is checked.
+	 *
+	 * If match is NULL, *item and the current object are compared.
+	 *
+	 * @warning Only use pointers as user supplied data.
+	 *
+	 * @param match			comparison function to call on each object, or NULL
+	 * @param item			the list item, if found
+	 * @param ...			user data to supply to match function (limited to 5 arguments)
+	 * @return				SUCCESS if found, NOT_FOUND otherwise
+	 */
+	status_t (*find_first) (linked_list_t *this, linked_list_match_t match,
+							void **item, ...);
+
+	/** Find the last matching element in the list.
+	 *
+	 * The first object passed to the match function is the current list item,
+	 * followed by the user supplied data.
+	 * If the supplied function returns TRUE this function returns SUCCESS, and
+	 * the current object is returned in the third parameter, otherwise,
+	 * the next item is checked.
+	 *
+	 * If match is NULL, *item and the current object are compared.
+	 *
+	 * @warning Only use pointers as user supplied data.
+	 *
+	 * @param match			comparison function to call on each object, or NULL
+	 * @param item			the list item, if found
+	 * @param ...			user data to supply to match function (limited to 5 arguments)
+	 * @return				SUCCESS if found, NOT_FOUND otherwise
+	 */
+	status_t (*find_last) (linked_list_t *this, linked_list_match_t match,
+						   void **item, ...);
+
+	/**
+	 * Invoke a method on all of the contained objects.
+	 *
+	 * If a linked list contains objects with function pointers,
+	 * invoke() can call a method on each of the objects. The
+	 * method is specified by an offset of the function pointer,
+	 * which can be evalutated at compile time using the offsetof
+	 * macro, e.g.: list->invoke(list, offsetof(object_t, method));
+	 *
+	 * @warning Only use pointers as user supplied data.
+	 *
+	 * @param offset	offset of the method to invoke on objects
+	 * @param ...		user data to supply to called function (limited to 5 arguments)
+	 */
+	void (*invoke_offset) (linked_list_t *this, size_t offset, ...);
+
+	/**
+	 * Invoke a function on all of the contained objects.
+	 *
+	 * @warning Only use pointers as user supplied data.
+	 *
+	 * @param function	offset of the method to invoke on objects
+	 * @param ...		user data to supply to called function (limited to 5 arguments)
+	 */
+	void (*invoke_function) (linked_list_t *this, linked_list_invoke_t function, ...);
+
+	/**
+	 * Clones a list and its objects using the objects' clone method.
+	 *
+	 * @param offset	offset ot the objects clone function
+	 * @return			cloned list
+	 */
+	linked_list_t *(*clone_offset) (linked_list_t *this, size_t offset);
+
+	/**
+	 * Clones a list and its objects using a given function.
+	 *
+	 * @param function	function that clones an object
+	 * @return			cloned list
+	 */
+	linked_list_t *(*clone_function) (linked_list_t *this, void*(*)(void*));
+
+	/**
+	 * Destroys a linked_list object.
+	 */
+	void (*destroy) (linked_list_t *this);
+
+	/**
+	 * Destroys a list and its objects using the destructor.
+	 *
+	 * If a linked list and the contained objects should be destroyed, use
+	 * destroy_offset. The supplied offset specifies the destructor to
+	 * call on each object. The offset may be calculated using the offsetof
+	 * macro, e.g.: list->destroy_offset(list, offsetof(object_t, destroy));
+	 *
+	 * @param offset	offset of the objects destructor
+	 */
+	void (*destroy_offset) (linked_list_t *this, size_t offset);
+
+	/**
+	 * Destroys a list and its contents using a a cleanup function.
+	 *
+	 * If a linked list and its contents should get destroyed using a specific
+	 * cleanup function, use destroy_function. This is useful when the
+	 * list contains malloc()-ed blocks which should get freed,
+	 * e.g.: list->destroy_function(list, free);
+	 *
+	 * @param function	function to call on each object
+	 */
+	void (*destroy_function) (linked_list_t *this, void (*)(void*));
+};
+
+/**
+ * Creates an empty linked list object.
+ *
+ * @return		linked_list_t object.
+ */
+linked_list_t *linked_list_create(void);
+
+/**
+ * Creates a linked list from an enumerator.
+ *
+ * @param enumerator	enumerator over void*, gets destroyed
+ * @return				linked_list_t object, containing enumerated values
+ */
+linked_list_t *linked_list_create_from_enumerator(enumerator_t *enumerator);
+
+/**
+ * Creates a linked list from a NULL terminated vararg list of items.
+ *
+ * @param first			first item
+ * @param ...			subsequent items, terminated by NULL
+ * @return				linked_list_t object, containing passed items
+ */
+linked_list_t *linked_list_create_with_items(void *first, ...);
+
+#endif /** LINKED_LIST_H_ @}*/