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/* Sub extension for handling RADIUS Accounting-Request messages */

#define IN_EXTENSION
#define DEFINE_DEBUG_MACRO	sub_acct
#define DECLARE_API_POINTERS
#include <waaad/waaad.h>

#include "rg_common.h"

#ifndef SUB_ACCT_VERBO
#define SUB_ACCT_VERBO 0
#endif /* SUB_ACCT_VERBO */

int sub_acct_verbosity = SUB_ACCT_VERBO;

struct rga_conf_state {
	char * conffile;
	void * dl_handle;
};

static struct rga_conf_state * acct_conf_parse(char * conffile)
{
	struct rga_conf_state * cs;
	
	TRACE_ENTRY("%p", conffile);
	
	CHECK_MALLOC_DO( cs = malloc(sizeof(struct rga_conf_state)), return NULL );
	memset(cs, 0, sizeof(struct rga_conf_state));
	
	cs->conffile = conffile;
	
	if (conffile) {
		TRACE_DEBUG(INFO, "Sub extension Accounting (RFC2866) initialized with configuration: '%s'", cs->conffile);
	} else {
		TRACE_DEBUG(INFO, "Sub extension Accounting (RFC2866) initialized with default configuration");
	}
	
	CHECK_FCT_DO( rg_pointers_init(&cs->dl_handle), return NULL );
	
	return cs;
}

static void acct_conf_free(struct rga_conf_state * cs)
{
	TRACE_ENTRY("%p", cs);
	CHECK_PARAMS_DO( cs, );
	rg_pointers_fini(&cs->dl_handle);
	free(cs);
	return;
}

static int acct_rad_req(struct rga_conf_state * cs, sess_id_t * session, struct radius_msg * rad_req, struct radius_msg ** rad_ans, msg_t ** diam_fw, void * cli )
{
	int idx;
	int got_id = 0;
	uint32_t status_type;
	
	TRACE_ENTRY("%p %p %p %p %p %p", cs, session, rad_req, rad_ans, diam_fw, cli);
	CHECK_PARAMS(rad_req && (rad_req->hdr->code == RADIUS_CODE_ACCOUNTING_REQUEST) && rad_ans && diam_fw && *diam_fw);
	
	/* Check the message contains the NAS idnetification */
	for (idx = 0; idx < rad_req->attr_used; idx++) {
		struct radius_attr_hdr * attr = (struct radius_attr_hdr *)(rad_req->buf + rad_req->attr_pos[idx]);
		switch (attr->type) {
			case RADIUS_ATTR_NAS_IP_ADDRESS:
			case RADIUS_ATTR_NAS_IDENTIFIER:
			case RADIUS_ATTR_NAS_IPV6_ADDRESS:
				got_id = 1;
				break;
		}
	}
			
	/* Check basic information is there */
	if (!got_id || radius_msg_get_attr_int32(rad_req, RADIUS_ATTR_ACCT_STATUS_TYPE, &status_type)) {
		TRACE_DEBUG(INFO, "RADIUS Account-Request did not contain a NAS ip/identifier or Acct-Status-Type attribute, reject.");
		return EINVAL;
	}
	
	/* Handle the Accounting-On/Off case: nothing to do, just reply OK, since Diameter does not support this */
	if ((status_type == RADIUS_ACCT_STATUS_TYPE_ACCOUNTING_ON) || (status_type == RADIUS_ACCT_STATUS_TYPE_ACCOUNTING_OFF)) {
		TRACE_DEBUG(FULL, "Received Accounting-On Acct-Status-Type attribute, replying directly.");
		CHECK_MALLOC( *rad_ans = radius_msg_new(RADIUS_CODE_ACCOUNTING_RESPONSE, rad_req->hdr->identifier) );
		return -2;
	}
	
			/*
			      -  If the RADIUS message received is an Accounting-Request, the
        			 Acct-Status-Type attribute value must be converted to a
        			 Accounting-Record-Type AVP value.  If the Acct-Status-Type
        			 attribute value is STOP, the local server MUST issue a
        			 Session-Termination-Request message once the Diameter
        			 Accounting-Answer message has been received.
			*/

			/*
			      -  If the Accounting message contains an Acct-Termination-Cause
        			 attribute, it should be translated to the equivalent
        			 Termination-Cause AVP value.  (see below)
			*/

			/*
			      -  If the RADIUS message contains the Accounting-Input-Octets,
        			 Accounting-Input-Packets, Accounting-Output-Octets, or
        			 Accounting-Output-Packets, these attributes must be converted
        			 to the Diameter equivalents.  Further, if the Acct-Input-
        			 Gigawords or Acct-Output-Gigawords attributes are present,
        			 these must be used to properly compute the Diameter accounting
        			 AVPs.
			*/
	return ENOTSUP;
}

static int acct_diam_ans(struct rga_conf_state * cs, sess_id_t * session, msg_t ** diam_ans, struct radius_msg ** rad_fw, void * cli )
{
	TRACE_ENTRY("%p %p %p %p %p", cs, session, diam_ans, rad_fw, cli);
	CHECK_PARAMS(cs);

	return ENOTSUP;
}

int rga_register(int version, waaad_api_t * waaad_api, struct radius_gw_api * api)
{
	TRACE_ENTRY("%d %p %p", version, waaad_api, api);
	CHECK_PARAMS( waaad_api && api );
	
	if (version != RADIUS_GW_API_VER) {
		log_error("ABI version mismatch, please recompile this extension (%s)\n", __FILE__);
		return EINVAL;
	}
	
	/* Required to use the waaad api from this sub-extension: */
	EXTENSION_API_INIT_INTERN( API_MODULE_ALL, "sub_acct", waaad_api );
	
	/* Initialize the radius_gw api callbacks */
	api->rga_conf_parse_cb = acct_conf_parse;
	api->rga_conf_free_cb  = acct_conf_free;
	api->rga_rad_req_cb    = acct_rad_req;
	api->rga_diam_ans_cb   = acct_diam_ans;
	
	/* We're done, we must not initialize any state here since the extension must be re-entrant, but in sample_conf_parse */
	return 0;
}