1 files changed, 384 insertions, 0 deletions
diff --git a/src/libstrongswan/plugins/attr_sql/sql_attribute.c b/src/libstrongswan/plugins/attr_sql/sql_attribute.c
new file mode 100644
index 000000000..a89195b6d
--- /dev/null
+++ b/src/libstrongswan/plugins/attr_sql/sql_attribute.c
@@ -0,0 +1,384 @@
+/*
+ * Copyright (C) 2008 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 <time.h>
+
+#include <debug.h>
+#include <library.h>
+
+#include "sql_attribute.h"
+
+typedef struct private_sql_attribute_t private_sql_attribute_t;
+
+/**
+ * private data of sql_attribute
+ */
+struct private_sql_attribute_t {
+
+	/**
+	 * public functions
+	 */
+	sql_attribute_t public;
+
+	/**
+	 * database connection
+	 */
+	database_t *db;
+
+	/**
+	 * wheter to record lease history in lease table
+	 */
+	bool history;
+};
+
+/**
+ * lookup/insert an identity
+ */
+static u_int get_identity(private_sql_attribute_t *this, identification_t *id)
+{
+	enumerator_t *e;
+	u_int row;
+
+	/* look for peer identity in the identities table */
+	e = this->db->query(this->db,
+						"SELECT id FROM identities WHERE type = ? AND data = ?",
+						DB_INT, id->get_type(id), DB_BLOB, id->get_encoding(id),
+						DB_UINT);
+
+	if (e && e->enumerate(e, &row))
+	{
+		e->destroy(e);
+		return row;
+	}
+	DESTROY_IF(e);
+	/* not found, insert new one */
+	if (this->db->execute(this->db, &row,
+				  "INSERT INTO identities (type, data) VALUES (?, ?)",
+				  DB_INT, id->get_type(id), DB_BLOB, id->get_encoding(id)) == 1)
+	{
+		return row;
+	}
+	return 0;
+}
+
+/**
+ * Lookup pool by name
+ */
+static u_int get_pool(private_sql_attribute_t *this, char *name, u_int *timeout)
+{
+	enumerator_t *e;
+	u_int pool;
+
+	e = this->db->query(this->db, "SELECT id, timeout FROM pools WHERE name = ?",
+						DB_TEXT, name, DB_UINT, DB_UINT);
+	if (e && e->enumerate(e, &pool, timeout))
+	{
+		e->destroy(e);
+		return pool;
+	}
+	DESTROY_IF(e);
+	return 0;
+}
+
+/**
+ * Look up an existing lease
+ */
+static host_t* check_lease(private_sql_attribute_t *this, char *name,
+						   u_int pool, u_int identity)
+{
+	while (TRUE)
+	{
+		u_int id;
+		chunk_t address;
+		enumerator_t *e;
+		time_t now = time(NULL);
+
+		e = this->db->query(this->db,
+				"SELECT id, address FROM addresses "
+				"WHERE pool = ? AND identity = ? AND released != 0 LIMIT 1",
+				DB_UINT, pool, DB_UINT, identity, DB_UINT, DB_BLOB);
+		if (!e || !e->enumerate(e, &id, &address))
+		{
+			DESTROY_IF(e);
+			break;
+		}
+		address = chunk_clonea(address);
+		e->destroy(e);
+
+		if (this->db->execute(this->db, NULL,
+				"UPDATE addresses SET acquired = ?, released = 0 "
+				"WHERE id = ? AND identity = ? AND released != 0",
+				DB_UINT, now, DB_UINT, id, DB_UINT, identity) > 0)
+		{
+			host_t *host;
+
+			host = host_create_from_chunk(AF_UNSPEC, address, 0);
+			if (host)
+			{
+				DBG1("acquired existing lease for address %H in pool '%s'",
+					 host, name);
+				return host;
+			}
+		}
+	}
+	return NULL;
+}
+
+/**
+ * We check for unallocated addresses or expired leases. First we select an
+ * address as a candidate, but double check later on if it is still available
+ * during the update operation. This allows us to work without locking.
+ */
+static host_t* get_lease(private_sql_attribute_t *this, char *name,
+						 u_int pool, u_int timeout, u_int identity)
+{
+	while (TRUE)
+	{
+		u_int id;
+		chunk_t address;
+		enumerator_t *e;
+		time_t now = time(NULL);
+		int hits;
+
+		if (timeout)
+		{
+			/* check for an expired lease */
+			e = this->db->query(this->db,
+				"SELECT id, address FROM addresses "
+				"WHERE pool = ? AND released != 0 AND released < ? LIMIT 1",
+				DB_UINT, pool, DB_UINT, now - timeout, DB_UINT, DB_BLOB);
+		}
+		else
+		{
+			/* with static leases, check for an unallocated address */
+			e = this->db->query(this->db,
+				"SELECT id, address FROM addresses "
+				"WHERE pool = ? AND identity = 0 LIMIT 1",
+				DB_UINT, pool, DB_UINT, DB_BLOB);
+
+		}
+
+		if (!e || !e->enumerate(e, &id, &address))
+		{
+			DESTROY_IF(e);
+			break;
+		}
+		address = chunk_clonea(address);
+		e->destroy(e);
+
+		if (timeout)
+		{
+			hits = this->db->execute(this->db, NULL,
+						"UPDATE addresses SET "
+						"acquired = ?, released = 0, identity = ? "
+						"WHERE id = ? AND released != 0 AND released < ?",
+						DB_UINT, now, DB_UINT, identity,
+						DB_UINT, id, DB_UINT, now - timeout);
+		}
+		else
+		{
+			hits = this->db->execute(this->db, NULL,
+						"UPDATE addresses SET "
+						"acquired = ?, released = 0, identity = ? "
+						"WHERE id = ? AND identity = 0",
+						DB_UINT, now, DB_UINT, identity, DB_UINT, id);
+		}
+		if (hits > 0)
+		{
+			host_t *host;
+
+			host = host_create_from_chunk(AF_UNSPEC, address, 0);
+			if (host)
+			{
+				DBG1("acquired new lease for address %H in pool '%s'",
+					 host, name);
+				return host;
+			}
+		}
+	}
+	DBG1("no available address found in pool '%s'", name);
+	return NULL;
+}
+
+/**
+ * Implementation of attribute_provider_t.acquire_address
+ */
+static host_t* acquire_address(private_sql_attribute_t *this,
+							   char *names, identification_t *id,
+							   host_t *requested)
+{
+	host_t *address = NULL;
+	u_int identity, pool, timeout;
+
+	identity = get_identity(this, id);
+	if (identity)
+	{
+		/* check for a single pool first (no concatenation and enumeration) */
+		if (strchr(names, ',') == NULL)
+		{
+			pool = get_pool(this, names, &timeout);
+			if (pool)
+			{
+				/* check for an existing lease */
+				address = check_lease(this, names, pool, identity);
+				if (address == NULL)
+				{
+					/* get an unallocated address or expired lease */
+					address = get_lease(this, names, pool, timeout, identity);
+				}
+			}
+		}
+		else
+		{
+			enumerator_t *enumerator;
+			char *name;
+
+			/* in a first step check for an existing lease over all pools */
+			enumerator = enumerator_create_token(names, ",", " ");
+			while (enumerator->enumerate(enumerator, &name))
+			{
+				pool = get_pool(this, name, &timeout);
+				if (pool)
+				{
+					address = check_lease(this, name, pool, identity);
+					if (address)
+					{
+						enumerator->destroy(enumerator);
+						return address;
+					}
+				}
+			}
+			enumerator->destroy(enumerator);
+
+			/* in a second step get an unallocated address or expired lease */
+			enumerator = enumerator_create_token(names, ",", " ");
+			while (enumerator->enumerate(enumerator, &name))
+			{
+				pool = get_pool(this, name, &timeout);
+				if (pool)
+				{
+					address = get_lease(this, name, pool, timeout, identity);
+					if (address)
+					{
+						break;
+					}
+				}
+			}
+			enumerator->destroy(enumerator);
+		}
+	}
+	return address;
+}
+
+/**
+ * Implementation of attribute_provider_t.release_address
+ */
+static bool release_address(private_sql_attribute_t *this,
+							char *name, host_t *address, identification_t *id)
+{
+	enumerator_t *enumerator;
+	bool found = FALSE;
+	time_t now = time(NULL);
+
+	enumerator = enumerator_create_token(name, ",", " ");
+	while (enumerator->enumerate(enumerator, &name))
+	{
+		u_int pool, timeout;
+
+		pool = get_pool(this, name, &timeout);
+		if (pool)
+		{
+			if (this->history)
+			{
+				this->db->execute(this->db, NULL,
+					"INSERT INTO leases (address, identity, acquired, released)"
+					" SELECT id, identity, acquired, ? FROM addresses "
+					" WHERE pool = ? AND address = ?",
+					DB_UINT, now, DB_UINT, pool,
+					DB_BLOB, address->get_address(address));
+			}
+			if (this->db->execute(this->db, NULL,
+					"UPDATE addresses SET released = ? WHERE "
+					"pool = ? AND address = ?", DB_UINT, time(NULL),
+					DB_UINT, pool, DB_BLOB, address->get_address(address)) > 0)
+			{
+				found = TRUE;
+				break;
+			}
+		}
+	}
+	enumerator->destroy(enumerator);
+	return found;
+}
+
+/**
+ * Implementation of sql_attribute_t.create_attribute_enumerator
+ */
+static enumerator_t* create_attribute_enumerator(private_sql_attribute_t *this,
+											identification_t *id, host_t *vip)
+{
+	if (vip)
+	{
+		enumerator_t *enumerator;
+
+		enumerator = this->db->query(this->db,
+						"SELECT type, value FROM attributes", DB_INT, DB_BLOB);
+		if (enumerator)
+		{
+			return enumerator;
+		}
+	}
+	return enumerator_create_empty();
+}
+
+/**
+ * Implementation of sql_attribute_t.destroy
+ */
+static void destroy(private_sql_attribute_t *this)
+{
+	free(this);
+}
+
+/*
+ * see header file
+ */
+sql_attribute_t *sql_attribute_create(database_t *db)
+{
+	private_sql_attribute_t *this = malloc_thing(private_sql_attribute_t);
+	time_t now = time(NULL);
+
+	this->public.provider.acquire_address = (host_t*(*)(attribute_provider_t *this, char*, identification_t *, host_t *))acquire_address;
+	this->public.provider.release_address = (bool(*)(attribute_provider_t *this, char*,host_t *, identification_t*))release_address;
+	this->public.provider.create_attribute_enumerator = (enumerator_t*(*)(attribute_provider_t*, identification_t *id, host_t *host))create_attribute_enumerator;
+	this->public.destroy = (void(*)(sql_attribute_t*))destroy;
+
+	this->db = db;
+	this->history = lib->settings->get_bool(lib->settings,
+						"libstrongswan.plugins.attr-sql.lease_history", TRUE);
+
+	/* close any "online" leases in the case we crashed */
+	if (this->history)
+	{
+		this->db->execute(this->db, NULL,
+					"INSERT INTO leases (address, identity, acquired, released)"
+					" SELECT id, identity, acquired, ? FROM addresses "
+					" WHERE released = 0", DB_UINT, now);
+	}
+	this->db->execute(this->db, NULL,
+					  "UPDATE addresses SET released = ? WHERE released = 0",
+					  DB_UINT, now);
+	return &this->public;
+}
+