/*
 *
 * adding/removing headers or any other data chunk from a message
 *
 * Copyright (C) 2001-2003 FhG Fokus
 *
 * This file is part of Kamailio, a free SIP server.
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 *
 * Kamailio 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
 *
 * Kamailio 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
 */
/*!
* \file
* \brief Kamailio core :: Adding/removing headers or any other data chunk from a message
* \ingroup core
* \author jiri, andrei, janakj
* Module: \ref core
*/

#ifndef lump_struct_h
#define lump_struct_h

#include "./parser/hf.h"


enum lump_op
{
	LUMP_NOP = 0,
	LUMP_DEL,
	LUMP_ADD,
	LUMP_ADD_SUBST,
	LUMP_ADD_OPT
};

enum lump_subst
{
	SUBST_NOP = 0, /* do nothing */
	SUBST_RCV_IP,
	SUBST_SND_IP, /* add ip address */
	SUBST_RCV_PORT,
	SUBST_SND_PORT, /* add port no */
	SUBST_RCV_PROTO,
	SUBST_SND_PROTO, /* add protocol(udp,tcp,tls)*/
	SUBST_RCV_ALL,
	SUBST_SND_ALL, /* ip:port;transport=proto */
	SUBST_RCV_ALL_EX,
	SUBST_SND_ALL_EX /* ip:port;transport=proto;sn=xyz */
};
/* Where:
				 * SND = sending, e.g the src ip of the outgoing message
				 * RCV = received e.g the dst ip of the original incoming msg,
				 *  or the ip of the ser socket on which the msg was received
				 * For SUBST_{RCV,SND}_ALL, :port is added only if port!=5060
				 * and transport=proto only if proto!=udp
				 */

enum lump_conditions
{
	COND_FALSE,			 /* always false */
	COND_TRUE,			 /* always true */
	COND_IF_DIFF_REALMS, /* true if RCV realm != SND realm */
	COND_IF_DIFF_AF,	 /* true if RCV af != SND af */
	COND_IF_DIFF_PROTO,	 /* true if RCV proto != SND proto */
	COND_IF_DIFF_PORT,	 /* true if RCV port != SND port */
	COND_IF_DIFF_IP,	 /* true if RCV ip != SND ip */
	COND_IF_RAND		 /* 50-50 random prob.of being true*/
};
/* Where:
						 * REALM= ip_addr:port:proto
						 * af   = address family (ipv4 or ipv6)
						 * proto = protocol (tcp, udp, tls)
						*/

enum lump_flag
{
	LUMPFLAG_NONE = 0,	   /* */
	LUMPFLAG_DUPED = 1,	   /* lump struct duplicated in pkg, with value
									* pointing to initial lump structure
									* - e.g., used for branch_route execution */
	LUMPFLAG_SHMEM = 2,	   /* lump stored in shared memory (e.g., tm) */
	LUMPFLAG_BRANCH = 4,   /* not in use ?!? */
	LUMPFLAG_COND_TRUE = 8 /* conditional lump processing */
};

#define LUMP_SET_COND_TRUE(_lump) (_lump)->flags |= LUMPFLAG_COND_TRUE
#define LUMP_IS_COND_TRUE(_lump) ((_lump)->flags & LUMPFLAG_COND_TRUE)

typedef struct lump
{
	enum _hdr_types_t type; /* HDR_VIA_T, HDR_OTHER_T (0), ... */
	enum lump_op op;		/* DEL, ADD, NOP, UNSPEC(=0) */

	union
	{
		int offset;				   /* used for DEL, MODIFY */
		enum lump_subst subst;	   /*what to subst: ip addr, port, proto*/
		enum lump_conditions cond; /* condition for LUMP_ADD_OPT */
		char *value;			   /* used for ADD */
	} u;
	int len; /* length of this header field */


	struct lump *before; /* list of headers to be inserted in front of the
								current one */
	struct lump *after;	 /* list of headers to be inserted immediately after
							* the current one */

	struct lump *next;

	enum lump_flag flags; /* additional hints for use from TM's shmem */
} sr_lump_t;


/*
 * hdrs must be kept sorted after their offset (DEL, NOP, UNSPEC)
 * and/or their position (ADD). E.g.:
 *  - to delete header Z insert it in to the list according to its offset
 *   and with op=DELETE
 * - if you want to add a new header X after a  header Y, insert Y in the list
 *   with op NOP and after it X (op ADD).
 * - if you want X before Y, insert X in Y's before list.
 * - if you want X to be the first header just put it first in hdr_lst.
 *  -if you want to replace Y with X, insert Y with op=DELETE and then X with
 *  op=ADD.
 * before and after must contain only ADD ops!
 *
 * Difference between "after" & "next" when Adding:
 * "after" forces the new header immediately after the current one while
 * "next" means another header can be inserted between them.
 *
 */

/* frees the content of a lump struct */
void free_lump(struct lump *l);
/* frees an entire lump list, recursively */
void free_lump_list(struct lump *lump_list);
/* count applied lumps in a list having a specific type */
unsigned int count_applied_lumps(struct lump *ll, int type);
#endif
