modules_s/avp/avp.c

/*
 * $Id$
 *
 * Copyright (C) 2004 FhG Fokus
 *
 * This file is part of ser, a free SIP server.
 *
 * ser 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
 *
 * For a license to use the ser software under conditions
 * other than those described here, or to purchase support for this
 * software, please contact iptel.org by e-mail at the following addresses:
 *    info@iptel.org
 *
 * ser 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/*
 *  2005-03-28  avp_destination & xlset_destination - handle both nameaddr & uri texts (mma)
 *  2005-12-22  merge changes from private branch (mma)
 *  2006-01-03  avp_body merged (mma)
 */

#include <string.h>
#include <stdlib.h>
#ifdef EXTRA_DEBUG
#include <assert.h>
#endif
#include "../../sr_module.h"
#include "../../error.h"
#include "../../lump_struct.h"
#include "../../data_lump.h"
#include "../../data_lump_rpl.h"
#include "../../usr_avp.h"
#include "../../mem/mem.h"
#include "../../parser/parse_uri.h"
#include "../../parser/msg_parser.h"
#include "../../parser/parse_nameaddr.h"
#include "../../ut.h"
#include "../../dset.h"
#include "../../trim.h"
#include "../../str.h"
#include "../../dprint.h"
#include "../../re.h"
#include "../../action.h"

#include "../../parser/parse_hname2.h"
#include "../xlog/xl_lib.h"
#define NO_SCRIPT -1

MODULE_VERSION

/* name of attributed used to store flags with command flags2attr */
#define HDR_ID 0
#define HDR_STR 1

#define PARAM_DELIM '/'
#define VAL_TYPE_INT (1<<0)
#define VAL_TYPE_STR (1<<1)

struct hdr_name {
        enum {hdrId, hdrStr} kind;
        union {
                int n;
                str s;
        } name;
        char field_delimiter;
        char array_delimiter;
        int val_types;
};

static int xlbuf_size=256;
static char* xlbuf=NULL;
static str* xl_nul=NULL;
static xl_print_log_f* xl_print=NULL;
static xl_parse_format_f* xl_parse=NULL;
static xl_elog_free_all_f* xl_free=NULL;
static xl_get_nulstr_f* xl_getnul=NULL;

static int mod_init();
static int set_iattr(struct sip_msg* msg, char* p1, char* p2);
static int set_sattr(struct sip_msg* msg, char* p1, char* p2);
static int print_attr(struct sip_msg* msg, char* p1, char* p2);
static int del_attr(struct sip_msg* msg, char* p1, char* p2);
static int subst_attr(struct sip_msg* msg, char* p1, char* p2);
static int flags2attr(struct sip_msg* msg, char* p1, char* p2);
static int attr2uri(struct sip_msg* msg, char* p1, char* p2);
static int dump_attrs(struct sip_msg* msg, char* p1, char* p2);
static int attr_equals(struct sip_msg* msg, char* p1, char* p2);
static int attr_exists(struct sip_msg* msg, char* p1, char* p2);
static int attr_equals_xl(struct sip_msg* msg, char* p1, char* p2);
static int xlset_attr(struct sip_msg* msg, char* p1, char* p2);
static int xlfix_attr(struct sip_msg* msg, char* p1, char* p2);
static int insert_req(struct sip_msg* msg, char* p1, char* p2);
static int append_req(struct sip_msg* msg, char* p1, char* p2);
static int replace_req(struct sip_msg* msg, char* p1, char* p2);
static int append_reply(struct sip_msg* msg, char* p1, char* p2);
static int attr_destination(struct sip_msg* msg, char* p1, char* p2);
static int xlset_destination(struct sip_msg* msg, char* p1, char* p2);
static int attr_hdr_body2attrs(struct sip_msg* msg, char* p1, char* p2);
static int attr_hdr_body2attrs2(struct sip_msg* msg, char* p1, char* p2);
static int del_attrs(struct sip_msg* msg, char* p1, char* p2);

static int set_iattr_fixup(void**, int);
static int avpid_fixup(void**, int);
static int subst_attr_fixup(void**, int);
static int fixup_part(void**, int);
static int fixup_xl_1(void**, int);
static int fixup_attr_1_xl_2(void**, int);
static int fixup_str_1_attr_2(void**, int);
static int xlfix_attr_fixup(void** param, int param_no);
static int attr_hdr_body2attrs_fixup(void**, int);
static int attr_hdr_body2attrs2_fixup(void**, int);
static int avpgroup_fixup(void**, int);

/*
 * Exported functions
 */
static cmd_export_t cmds[] = {
    {"set_iattr",         set_iattr,            2, set_iattr_fixup,            REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"set_sattr",         set_sattr,            2, fixup_var_str_12,           REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"set_attr",          set_sattr,            2, fixup_var_str_12,           REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"print_attr",        print_attr,           1, avpid_fixup,                REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"del_attr",          del_attr,             1, avpid_fixup,                REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE}, 
    {"del_attrs",         del_attrs,            1, avpgroup_fixup,             REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE}, 
    {"subst_attr",        subst_attr,           2, subst_attr_fixup,           REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"flags2attr",        flags2attr,           1, avpid_fixup,                REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"attr2uri",          attr2uri,             1, fixup_part,                 REQUEST_ROUTE | FAILURE_ROUTE},
    {"attr2uri",          attr2uri,             2, fixup_part,                 REQUEST_ROUTE | FAILURE_ROUTE},
    {"dump_attrs",        dump_attrs,           0, 0,                          REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"dump_attrs",        dump_attrs,           1, avpgroup_fixup,             REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"attr_equals",       attr_equals,          2, fixup_var_str_12,           REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"attr_exists",       attr_exists,          1 , fixup_var_str_1,           REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"attr_equals_xl",    attr_equals_xl,       2, fixup_attr_1_xl_2,          REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"xlset_attr",        xlset_attr,           2, fixup_attr_1_xl_2,          REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"xlfix_attr",        xlfix_attr,           1, xlfix_attr_fixup,           REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE}, 
    {"insert_attr_hf",    insert_req,           2, fixup_str_1_attr_2,         REQUEST_ROUTE | FAILURE_ROUTE},
    {"insert_attr_hf",    insert_req,           1, fixup_str_1_attr_2,         REQUEST_ROUTE | FAILURE_ROUTE},
    {"append_attr_hf",    append_req,           2, fixup_str_1_attr_2,         REQUEST_ROUTE | FAILURE_ROUTE},
    {"append_attr_hf",    append_req,           1, fixup_str_1_attr_2,         REQUEST_ROUTE | FAILURE_ROUTE},
    {"replace_attr_hf",   replace_req,          2, fixup_str_1_attr_2,         REQUEST_ROUTE | FAILURE_ROUTE},
    {"replace_attr_hf",   replace_req,          1, fixup_str_1_attr_2,         REQUEST_ROUTE | FAILURE_ROUTE},
    {"attr_to_reply",     append_reply,         2, fixup_str_1_attr_2,         REQUEST_ROUTE | FAILURE_ROUTE},
    {"attr_to_reply",     append_reply,         1, fixup_str_1_attr_2,         REQUEST_ROUTE | FAILURE_ROUTE},
    {"attr_destination",  attr_destination,     1, avpid_fixup,                REQUEST_ROUTE | FAILURE_ROUTE}, 
    {"xlset_destination", xlset_destination,    1, fixup_xl_1,                 REQUEST_ROUTE},
    {"hdr_body2attrs",    attr_hdr_body2attrs,  2, attr_hdr_body2attrs_fixup,  REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {"hdr_body2attrs2",   attr_hdr_body2attrs2, 2, attr_hdr_body2attrs2_fixup, REQUEST_ROUTE | ONREPLY_ROUTE | FAILURE_ROUTE},
    {0, 0, 0, 0, 0}
};


/*
 * Exported parameters
 */
static param_export_t params[] = {
    {"xlbuf_size", PARAM_INT, &xlbuf_size},
    {0, 0, 0}
};


struct module_exports exports = {
    "avp",
    cmds,       /* Exported commands */
    0,          /* RPC */
    params,     /* Exported parameters */
    mod_init,          /* module initialization function */
    0,          /* response function*/
    0,          /* destroy function */
    0,          /* oncancel function */
    0           /* per-child init function */
};


static int set_iattr_fixup(void** param, int param_no)
{
    if (param_no == 1) {
        return fixup_var_str_12(param, param_no);
    } else {
        return fixup_var_int_12(param, param_no);
    }
}


static int get_avp_id(avp_ident_t* id, fparam_t* p, struct sip_msg* msg)
{
    str str_id;
    avp_t* avp;
    avp_value_t val;
    int ret;

    switch(p->type) {
    case FPARAM_AVP:
        avp = search_avp(p->v.avp, &val, 0);
        if (!avp) {
            DBG("get_avp_id: AVP %s does not exist\n", p->orig);
            return -1;
        }
        if ((avp->flags & AVP_VAL_STR) == 0) {
            DBG("get_avp_id: Not a string AVP\n");
            return -1;
        }
        str_id = val.s;
        break;

    case FPARAM_SELECT:
        ret = run_select(&str_id, p->v.select, msg);
        if (ret < 0 || ret > 0) return -1;
        break;

        case FPARAM_STR:
        str_id = p->v.str;
        break;

    default:
        ERR("Invalid parameter type in get_avp_id\n");
        return -1;
    }

    return parse_avp_ident(&str_id, id);
}


static int set_iattr(struct sip_msg* msg, char* p1, char* p2)
{
    avp_ident_t avpid;
    int_str value;

    if (get_avp_id(&avpid, (fparam_t*)p1, msg) < 0) {
        return -1;
    }
    
    if (get_int_fparam(&value.n, msg, (fparam_t*)p2) < 0) {
        ERR("Error while obtaining attribute value from '%s'\n", ((fparam_t*)p1)->orig);
        return -1;
    }
    
    if (add_avp(avpid.flags | AVP_NAME_STR, avpid.name, value) != 0) {
        ERR("add_avp failed\n");
        return -1;
    }
    return 1;
}


static int set_sattr(struct sip_msg* msg, char* p1, char* p2)
{
    avp_ident_t avpid;
    int_str value;
    
    if (get_avp_id(&avpid, (fparam_t*)p1, msg) < 0) {
        return -1;
    }

    if (get_str_fparam(&value.s, msg, (fparam_t*)p2) < 0) {
        ERR("Error while obtaining attribute value from '%s'\n", ((fparam_t*)p2)->orig);
        return -1;
    }
    
    if (add_avp(avpid.flags | AVP_NAME_STR | AVP_VAL_STR, avpid.name, value) != 0) {
        ERR("add_avp failed\n");
        return -1;
    }
    
    return 1;
}


static int avpid_fixup(void** param, int param_no)
{
    if (param_no == 1) {
                if (fix_param(FPARAM_AVP, param) == 0) return 0;
                ERR("Invalid AVP identifier: '%s'\n", (char*)*param);
                return -1;
    }
    return 0;
}


static int print_attr(struct sip_msg* msg, char* p1, char* p2)
{
    fparam_t* fp;
    int_str value;
    avp_t *avp;

    fp = (fparam_t*)p1;
    
    avp = search_avp(fp->v.avp, &value, NULL);
    if (avp == 0) {
        LOG(L_INFO, "AVP '%s' not found\n", fp->orig);
        return -1;
    }
    
    if (avp->flags & AVP_VAL_STR) {
        LOG(L_INFO, "AVP: '%s'='%.*s'\n", 
            fp->orig, value.s.len, ZSW(value.s.s));
    } else {
        LOG(L_INFO, "AVP: '%s'=%d\n", fp->orig, value.n);
    }
    return 1;
}


static int del_attr(struct sip_msg* msg, char* p1, char* p2)
{
    fparam_t* fp;
    avp_t* avp;
    struct search_state st;     
    
    fp = (fparam_t*)p1;
    
    avp = search_avp(fp->v.avp, 0, &st);
    while (avp) {
        destroy_avp(avp);
        avp = search_next_avp(&st, 0);
    }
    return 1;
}


static int del_attrs(struct sip_msg* msg, char* p1, char* p2)
{
    return (reset_avp_list((unsigned long)p1) == 0) ? 1 : -1;
}
                        

static int subst_attr_fixup(void** param, int param_no)
{
    if (param_no == 1) {
                return avpid_fixup(param, 1);
    }
    if (param_no == 2) {
                if (fix_param(FPARAM_SUBST, param) != 0) return -1;
    }
    return 0;
}


static int subst_attr(struct sip_msg* msg, char* p1, char* p2)
{
    avp_t* avp;
    avp_value_t val;
    str *res = NULL;
    int count;
    avp_ident_t* name = &((fparam_t*)p1)->v.avp;

    if ((avp = search_avp(*name, &val, NULL))) {
        if (avp->flags & AVP_VAL_STR) {
            res = subst_str(val.s.s, msg, ((fparam_t*)p2)->v.subst, &count);
            if (res == NULL) {
                ERR("avp_subst: error while running subst\n");
                goto error;
            }

            DBG("avp_subst: %d, result %.*s\n", count, res->len, ZSW(res->s));
            val.s = *res;
            
            if (add_avp_before(avp, name->flags | AVP_VAL_STR, name->name, val)) {
                ERR("avp_subst: error while adding new AVP\n");
                goto error;
            }
            
            destroy_avp(avp);
            return 1;
        } else {
            ERR("avp_subst: AVP has numeric value\n");
            goto error;
        }
    } else {
        ERR("avp_subst: AVP[%.*s] index %d, flags %x not found\n", 
            name->name.s.len, name->name.s.s,
            name->index, name->flags);
        goto error;
    }

 error:
    if (res) pkg_free(res);
    return -1;
}


static int flags2attr(struct sip_msg* msg, char* p1, char* p2)
{
    avp_ident_t* id;
    int_str value;
    
    value.n = msg->flags;
    
    id = &((fparam_t*)p1)->v.avp;

    if (add_avp(id->flags, id->name, value) != 0) {
        ERR("add_avp failed\n");
        return -1;
    }
    
    return 1;
}


static int fixup_part(void** param, int param_no) 
{
    int i;
    fparam_t* fp;
    
    static struct {
                char* s;
                int i;
    } fixup_parse[] = {
                {"", SET_URI_T},
                {"prefix", PREFIX_T},
                {"uri", SET_URI_T},
                {"username", SET_USER_T},
                {"user", SET_USER_T},
                {"usernamepassword", SET_USERPASS_T},
                {"userpass", SET_USERPASS_T},
                {"domain", SET_HOST_T},
                {"host", SET_HOST_T},
                {"domainport", SET_HOSTPORT_T},
                {"hostport", SET_HOSTPORT_T},
                {"port", SET_PORT_T},
                {"strip", STRIP_T},
                {"strip_tail", STRIP_TAIL_T},
                {0, 0}
    };
    
    if (param_no == 1) {
                return avpid_fixup(param, 1);
    } else if (param_no == 2) {
                /* Create fparam structure */
                if (fix_param(FPARAM_STRING, param) != 0) return -1;
                
                /* We will parse the string now and store the value
                 * as int
                 */
                fp = (fparam_t*)*param;
                fp->type = FPARAM_INT;
                
                for(i = 0; fixup_parse[i].s; i++) {
                        if (!strcasecmp(fp->orig, fixup_parse[i].s)) {
                                fp->v.i = fixup_parse[i].i;
                                return 1;
                        }
                }
                
                ERR("Invalid parameter value: '%s'\n", fp->orig);
                return -1;
    }
    return 0;
}


static int attr2uri(struct sip_msg* msg, char* p1, char* p2)
{
    int_str value;
    avp_t* avp_entry;
    struct action act;
        struct run_act_ctx ra_ctx;
    int pnr;
    unsigned int u;
    
    if (p2) {
                pnr = ((fparam_t*)p2)->v.i;
    } else {
                pnr = SET_URI_T;
    }
    
    avp_entry = search_avp(((fparam_t*)p1)->v.avp, &value, NULL);
    if (avp_entry == 0) {
                ERR("attr2uri: AVP '%s' not found\n", ((fparam_t*)p1)->orig);
                return -1;
    }
    
    memset(&act, 0, sizeof(act));
        
    if ((pnr == STRIP_T) || (pnr == STRIP_TAIL_T)) {
                /* we need integer value for these actions */
        if (avp_entry->flags & AVP_VAL_STR) {
                        if (str2int(&value.s, &u)) {
                                ERR("not an integer value: %.*s\n",
                                        value.s.len, value.s.s);
                                return -1;
                        }
                        act.val[0].u.number = u;
                } else {
                        act.val[0].u.number = value.n;
                }
                act.val[0].type = NUMBER_ST;
    } else {
                /* we need string value */
                if ((avp_entry->flags & AVP_VAL_STR) == 0) {
                        act.val[0].u.string = int2str(value.n, NULL);
                } else {
                        act.val[0].u.string = value.s.s;
                }
                act.val[0].type = STRING_ST;
    }
    act.type = pnr;
    init_run_actions_ctx(&ra_ctx);
    if (do_action(&ra_ctx, &act, msg) < 0) {
                ERR("failed to change ruri part.\n");
                return -1;
    }
    return 1;
}


/*
 * sends avp list to log in readable form
 *
 */
static void dump_avp_reverse(avp_t* avp)
{
    str* name;
    int_str val;
    
    if (avp) {
             /* AVPs are added to front of the list, reverse by recursion */
        dump_avp_reverse(avp->next);
        
        name=get_avp_name(avp);
        get_avp_val(avp, &val);
        switch(avp->flags&(AVP_NAME_STR|AVP_VAL_STR)) {
        case 0:
                 /* avp type ID, int value */
            LOG(L_INFO,"AVP[%d]=%d\n", avp->id, val.n);
            break;

        case AVP_NAME_STR:
                 /* avp type str, int value */
            name=get_avp_name(avp);
            LOG(L_INFO,"AVP[\"%.*s\"]=%d\n", name->len, name->s, val.n);
            break;

        case AVP_VAL_STR:
                 /* avp type ID, str value */
            LOG(L_INFO,"AVP[%d]=\"%.*s\"\n", avp->id, val.s.len, val.s.s);
            break;

        case AVP_NAME_STR|AVP_VAL_STR:
                 /* avp type str, str value */
            name=get_avp_name(avp);
            LOG(L_INFO,"AVP[\"%.*s\"]=\"%.*s\"\n", name->len, name->s, val.s.len, val.s.s);
            break;
        }
    }
}


static int dump_attrs(struct sip_msg* m, char* x, char* y)
{
    avp_list_t avp_list;
    unsigned long flags;

    if (x) {
        flags = (unsigned long)x;
    } else {
        flags = AVP_CLASS_ALL | AVP_TRACK_ALL;
    }


    if (flags & AVP_CLASS_GLOBAL) {
        avp_list = get_avp_list(AVP_CLASS_GLOBAL);
        INFO("class=GLOBAL\n");
        if (!avp_list) {
            LOG(L_INFO,"INFO: No AVP present\n");
        } else {
            dump_avp_reverse(avp_list);
        }
    }

    if (flags & AVP_CLASS_DOMAIN && flags & AVP_TRACK_FROM) {
        avp_list = get_avp_list(AVP_CLASS_DOMAIN | AVP_TRACK_FROM);
        INFO("track=FROM class=DOMAIN\n");
        if (!avp_list) {
            LOG(L_INFO,"INFO: No AVP present\n");
        } else {
            dump_avp_reverse(avp_list);
        }
    }

    if (flags & AVP_CLASS_DOMAIN && flags & AVP_TRACK_TO) {
        avp_list = get_avp_list(AVP_CLASS_DOMAIN | AVP_TRACK_TO);
        INFO("track=TO class=DOMAIN\n");
        if (!avp_list) {
            LOG(L_INFO,"INFO: No AVP present\n");
        } else {
            dump_avp_reverse(avp_list);
        }
    }

    if (flags & AVP_CLASS_USER && flags & AVP_TRACK_FROM) {
        avp_list = get_avp_list(AVP_CLASS_USER | AVP_TRACK_FROM);
        INFO("track=FROM class=USER\n");
        if (!avp_list) {
            LOG(L_INFO,"INFO: No AVP present\n");
        } else {
            dump_avp_reverse(avp_list);
        }
    }

    if (flags & AVP_CLASS_USER && flags & AVP_TRACK_TO) {
        avp_list = get_avp_list(AVP_CLASS_USER | AVP_TRACK_TO);
        INFO("track=TO class=USER\n");
        if (!avp_list) {
            LOG(L_INFO,"INFO: No AVP present\n");
        } else {
            dump_avp_reverse(avp_list);
        }
    }

    if (flags & AVP_CLASS_URI && flags & AVP_TRACK_FROM) {
        avp_list = get_avp_list(AVP_CLASS_URI | AVP_TRACK_FROM);
        INFO("track=FROM class=URI\n");
        if (!avp_list) {
            LOG(L_INFO,"INFO: No AVP present\n");
        } else {
            dump_avp_reverse(avp_list);
        }
    }   

    if (flags & AVP_CLASS_URI && flags & AVP_TRACK_TO) {
        avp_list = get_avp_list(AVP_CLASS_URI | AVP_TRACK_TO);
        INFO("track=TO class=URI\n");
        if (!avp_list) {
            LOG(L_INFO,"INFO: No AVP present\n");
        } else {
            dump_avp_reverse(avp_list);
        }
    }
    return 1;
}


/*
 *  returns 1 if msg contains an AVP with the given name and value,
 *  returns -1 otherwise
 */
static int attr_equals(struct sip_msg* msg, char* p1, char* p2)
{
    avp_ident_t avpid;
    int_str value, avp_value;
    avp_t* avp;
    struct search_state st;

    if (get_avp_id(&avpid, (fparam_t*)p1, msg) < 0) {
        return -1;
    }

    if (p2 && get_str_fparam(&value.s, msg, (fparam_t*)p2) < 0) {
        ERR("Error while obtaining attribute value from '%s'\n", ((fparam_t*)p2)->orig);
        return -1;
    }

    avp = search_avp(avpid, &avp_value, &st);
    if (avp == 0) return -1;

    if (!p2) return 1;
    
    while (avp != 0) {
        if (avp->flags & AVP_VAL_STR) {
            if ((avp_value.s.len == value.s.len) &&
                !memcmp(avp_value.s.s, value.s.s, avp_value.s.len)) {
                return 1;
            }
        } else {
            if (avp_value.n == str2s(value.s.s, value.s.len, 0)) {
                return 1;
            }
        }
        avp = search_next_avp(&st, &avp_value);
    }
    
    return -1;
}


static int attr_exists(struct sip_msg* msg, char* p1, char* p2)
{
        return attr_equals(msg, p1, NULL);
}


static int xl_printstr(struct sip_msg* msg, xl_elog_t* format, char** res, int* res_len)
{
    int len;
    
    if (!format || !res) {
        LOG(L_ERR, "xl_printstr: Called with null format or res\n");
        return -1;
    }
    
    if (!xlbuf) {
        xlbuf = pkg_malloc((xlbuf_size+1)*sizeof(char));
        if (!xlbuf) {
            LOG(L_CRIT, "xl_printstr: No memory left for format buffer\n");
            return -1;
        }
    }
    
    len = xlbuf_size;
    if (xl_print(msg, format, xlbuf, &len)<0) {
        LOG(L_ERR, "xl_printstr: Error while formating result\n");
        return -1;
    }
    
    if ((xl_nul) && (xl_nul->len == len) && !strncmp(xl_nul->s, xlbuf, len)) {
        return 0;
    }

    *res = xlbuf;
    if (res_len) {
        *res_len=len;
    }
    return len;
}


static int attr_equals_xl(struct sip_msg* msg, char* p1, char* format)
{
    avp_ident_t* avpid;
    avp_value_t avp_val;
    struct search_state st;
    str xl_val;
    avp_t* avp;
    
    avpid = &((fparam_t*)p1)->v.avp;

    if (xl_printstr(msg, (xl_elog_t*) format, &xl_val.s, &xl_val.len) > 0) {
        for (avp = search_avp(*avpid, &avp_val, &st); avp; avp = search_next_avp(&st, &avp_val)) {
            if (avp->flags & AVP_VAL_STR) {
                if ((avp_val.s.len == xl_val.len) &&
                    !memcmp(avp_val.s.s, xl_val.s, avp_val.s.len)) return 1;
            } else {
                if (avp_val.n == str2s(xl_val.s, xl_val.len, 0)) return 1;
            }
        }
        return -1;
    }
    
    ERR("avp_equals_xl:Error while expanding xl_format\n");
    return -1;
}

/* get the pointer to the xl lib functions */
static int get_xl_functions(void)
{
    if (!xl_print) {
        xl_print=(xl_print_log_f*)find_export("xprint", NO_SCRIPT, 0);
        
        if (!xl_print) {
            LOG(L_CRIT,"ERROR: cannot find \"xprint\", is module xlog loaded?\n");
            return -1;
        }
    }
    
    if (!xl_parse) {
        xl_parse=(xl_parse_format_f*)find_export("xparse", NO_SCRIPT, 0);
        
        if (!xl_parse) {
            LOG(L_CRIT,"ERROR: cannot find \"xparse\", is module xlog loaded?\n");
            return -1;
        }
    }

    if (!xl_free) {
        xl_free=(xl_elog_free_all_f*)find_export("xfree", NO_SCRIPT, 0);
        
        if (!xl_free) {
            LOG(L_CRIT,"ERROR: cannot find \"xfree\", is module xlog loaded?\n");
            return -1;
        }
    }

    if (!xl_nul) {
        xl_getnul=(xl_get_nulstr_f*)find_export("xnulstr", NO_SCRIPT, 0);
        if (xl_getnul) {
            xl_nul=xl_getnul();
        }
        
        if (!xl_nul){
            LOG(L_CRIT,"ERROR: cannot find \"xnulstr\", is module xlog loaded?\n");
            return -1;
        } else {
            LOG(L_INFO,"INFO: xlog null is \"%.*s\"\n", xl_nul->len, xl_nul->s);
        }
        
    }

    return 0;
}

/*
 * Convert xl format string to xl format description
 */
static int fixup_xl_1(void** param, int param_no)
{
    xl_elog_t* model;

    if (get_xl_functions()) return -1;

    if (param_no == 1) {
        if(*param) {
            if(xl_parse((char*)(*param), &model)<0) {
                LOG(L_ERR, "ERROR: xl_fixup: wrong format[%s]\n", (char*)(*param));
                return E_UNSPEC;
            }
            
            *param = (void*)model;
            return 0;
        } else {
            LOG(L_ERR, "ERROR: xl_fixup: null format\n");
            return E_UNSPEC;
        }
    }
    
    return 0;
}

static int fixup_attr_1_xl_2(void** param, int param_no)
{
    if (param_no == 1) {
        return avpid_fixup(param, 1);
    } else  if (param_no == 2) {
        return fixup_xl_1(param, 1);
    }
    return 0;
}


static int xlset_attr(struct sip_msg* msg, char* p1, char* format)
{
    avp_ident_t* avpid;
    avp_value_t val;
    
    avpid = &((fparam_t*)p1)->v.avp;

    if (xl_printstr(msg, (xl_elog_t*)format, &val.s.s, &val.s.len) > 0) {
        if (add_avp(avpid->flags | AVP_VAL_STR, avpid->name, val)) {
            ERR("xlset_attr:Error adding new AVP\n");
            return -1;
        }
        return 1;
    }
    
    ERR("xlset_attr:Error while expanding xl_format\n");
    return -1;
}

/*
 * get the xl function pointers and fix up the AVP parameter
 */
static int xlfix_attr_fixup(void** param, int param_no)
{
    if (get_xl_functions()) return -1;

    if (param_no == 1)
        return avpid_fixup(param, 1);

    return 0;
}

/* fixes an attribute containing xl formatted string to pure string runtime */
static int xlfix_attr(struct sip_msg* msg, char* p1, char* p2)
{
    avp_t* avp;
    avp_ident_t* avpid;
    avp_value_t val;
    xl_elog_t* format=NULL;
    int ret=-1;
    
    avpid = &((fparam_t*)p1)->v.avp;

    /* search the AVP */
    avp = search_avp(*avpid, &val, 0);
    if (!avp) {
        DBG("xlfix_attr: AVP does not exist\n");
        goto error;
    }
    if ((avp->flags & AVP_VAL_STR) == 0) {
        DBG("xlfix_attr: Not a string AVP\n");
        goto error;
    }

    /* parse the xl syntax -- AVP values are always
    zero-terminated */
    if (xl_parse(val.s.s, &format)<0) {
        LOG(L_ERR, "ERROR: xlfix_attr: wrong format[%s]\n", val.s.s);
        goto error;
    }

    if (xl_printstr(msg, format, &val.s.s, &val.s.len) > 0) {
        /* we must delete and re-add the AVP again */
        destroy_avp(avp);
        if (add_avp(avpid->flags | AVP_VAL_STR, avpid->name, val)) {
            ERR("xlfix_attr:Error adding new AVP\n");
            goto error;
        }
        /* everything went OK */
        ret = 1;
    }

error:
    /* free the parsed xl expression */
    if (format) xl_free(format);

    return ret;
}


static int request_hf_helper(struct sip_msg* msg, str* hf, avp_ident_t* ident, struct lump* anchor, struct search_state* st, int front, int reverse, int reply)
{
    struct lump* new_anchor;
    static struct search_state state;
    avp_t* avp;
    char* s;
    str fin_val;
    int len, ret;
    int_str val;
    struct hdr_field* pos, *found = NULL;
    
    if (!anchor && !reply) {
        
        if (parse_headers(msg, HDR_EOH_F, 0) == -1) {
            LOG(L_ERR, "ERROR: request_hf_helper: Error while parsing message\n");
            return -1;
        }
        
        pos = msg->headers;
        while (pos && (pos->type != HDR_EOH_T)) {
            if ((hf->len == pos->name.len)
                && (!strncasecmp(hf->s, pos->name.s, pos->name.len))) {
                found = pos;
                if (front) {
                    break;
                }
            }
            pos = pos->next;
        }
        
        if (found) {
            if (front) {
                len = found->name.s - msg->buf;
            } else {
                len = found->name.s + found->len - msg->buf;
            }
        } else {
            len = msg->unparsed - msg->buf;
        }
        
        new_anchor = anchor_lump(msg, len, 0, 0);
        if (new_anchor == 0) {
            LOG(L_ERR, "ERROR: request_hf_helper: Can't get anchor\n");
            return -1;
        }
    } else {
        new_anchor = anchor;
    }
    
    if (!st) {
        st = &state;
        avp = search_avp(*ident, NULL, st);
        ret = -1;
    } else {
        avp = search_next_avp(st, NULL);
        ret = 1;
    }
    
    if (avp) {
        if (reverse && (request_hf_helper(msg, hf, ident, new_anchor, st, front, reverse, reply) == -1)) {
            return -1;
        }
        
        get_avp_val(avp, &val);
        if (avp->flags & AVP_VAL_STR) {
            fin_val = val.s;
        } else {
            fin_val.s = int2str(val.n, &fin_val.len);
        }
        
        len = hf->len + 2 + fin_val.len + 2;
        s = (char*)pkg_malloc(len);
        if (!s) {
            LOG(L_ERR, "ERROR: request_hf_helper: No memory left for data lump\n");
            return -1;
        }
        
        memcpy(s, hf->s, hf->len);
        memcpy(s + hf->len, ": ", 2 );
        memcpy(s + hf->len+2, fin_val.s, fin_val.len );
        memcpy(s + hf->len + 2 + fin_val.len, CRLF, CRLF_LEN);
        
        if (reply) {
            if (add_lump_rpl( msg, s, len, LUMP_RPL_HDR | LUMP_RPL_NODUP) == 0) {
                LOG(L_ERR, "ERROR: request_hf_helper: Can't insert RPL lump\n");
                pkg_free(s);
                return -1;
            }
        } else {
            if ((front && (insert_new_lump_before(new_anchor, s, len, 0) == 0))
                || (!front && (insert_new_lump_after(new_anchor, s, len, 0) == 0))) {
                LOG(L_ERR, "ERROR: request_hf_helper: Can't insert lump\n");
                pkg_free(s);
                return -1;
            }
        }
        if (!reverse && (request_hf_helper(msg, hf, ident, new_anchor, st, front, reverse, reply) == -1)) {
            return -1;
        }
        return 1;
    };
    
         /* in case of topmost call (st==NULL) return error */
         /* otherwise it's OK, no more AVPs found */
    return ret; 
}


static int fixup_str_1_attr_2(void** param, int param_no)
{
    if (param_no == 1) {
        return fixup_var_str_12(param, 1);
    } else if (param_no == 2) {
        return avpid_fixup(param, 1);
    }
    return 0;
}


static int insert_req(struct sip_msg* msg, char* p1, char* p2)
{
    avp_ident_t ident, *avp;
    str hf;
    
    if (get_str_fparam(&hf, msg, (fparam_t*)p1) < 0) {
        ERR("Error while obtaining attribute value from '%s'\n", ((fparam_t*)p1)->orig);
        return -1;
    }

    if (p2) {
        avp = &((fparam_t*)p2)->v.avp;
    } else {
        ident.name.s = hf;
        ident.flags = AVP_NAME_STR;
        ident.index = 0;
        avp = &ident;
    }
    return (request_hf_helper(msg, &hf, avp, NULL, NULL, 1, 0, 0));
}


static int append_req(struct sip_msg* msg, char* p1, char* p2)
{
    avp_ident_t ident, *avp;
    str hf;

    if (get_str_fparam(&hf, msg, (fparam_t*)p1) < 0) {
        ERR("Error while obtaining attribute value from '%s'\n", ((fparam_t*)p1)->orig);
        return -1;
    }
    
    if (p2) {
        avp = &((fparam_t*)p2)->v.avp;
    } else {
        ident.name.s = hf;
        ident.flags = AVP_NAME_STR;
        ident.index = 0;
        avp = &ident;
    }
    return (request_hf_helper(msg, &hf, avp, NULL, NULL, 0, 1, 0));
}


static int replace_req(struct sip_msg* msg, char* p1, char* p2)
{
    struct hdr_field* pos;
    str hf;
    
    if (get_str_fparam(&hf, msg, (fparam_t*)p1) < 0) {
        ERR("Error while obtaining attribute value from '%s'\n", ((fparam_t*)p1)->orig);
        return -1;
    }
    
    if (parse_headers(msg, HDR_EOH_F, 0) == -1) {
        LOG(L_ERR, "ERROR: replace_req: Error while parsing message\n");
        return -1;
    }
    
    pos = msg->headers;
    while (pos && (pos->type != HDR_EOH_T)) {
        if (hf.len == pos->name.len
            && !strncasecmp(hf.s, pos->name.s, pos->name.len)) {
            if (del_lump(msg, pos->name.s - msg->buf, pos->len, 0) == 0) {
                LOG(L_ERR,"ERROR: Can't insert del lump\n");
                return -1;
            }
        }
        pos = pos->next;
    }
    return append_req(msg, p1, p2);
}


static int append_reply(struct sip_msg* msg, char* p1, char* p2)
{
    avp_ident_t ident, *avp;
    str hf;
    
    if (get_str_fparam(&hf, msg, (fparam_t*)p1) < 0) {
        ERR("Error while obtaining attribute value from '%s'\n", ((fparam_t*)p1)->orig);
        return -1;
    }
    
    if (p2) {
        avp = &((fparam_t*)p2)->v.avp;
    } else {
        ident.name.s = hf;
        ident.flags = AVP_NAME_STR;
        ident.index = 0;
        avp = &ident;
    }
    return (request_hf_helper(msg, &hf, avp, NULL, NULL, 0, 1, 1));
}


static int set_destination(struct sip_msg* msg, str* dest)
{
    name_addr_t nameaddr;
    
    if (!parse_nameaddr(dest, &nameaddr)) {
        return set_dst_uri(msg, &nameaddr.uri);
    } else {
             /* it is just URI, pass it through */
        return set_dst_uri(msg, dest);
    }
}


static int attr_destination(struct sip_msg* msg, char* p1, char* p2)
{
    avp_t* avp;
    avp_value_t val;
    
    if ((avp = search_avp(((fparam_t*)p1)->v.avp, &val, NULL))) {
        if (avp->flags & AVP_VAL_STR) {
            if (set_destination(msg, &val.s)) {
                LOG(L_ERR, "ERROR: avp_destination: Can't set dst uri\n");
                return -1;
            };
                /* dst_uri changed, so it makes sense to re-use the current uri for
                        forking */
                ruri_mark_new(); /* re-use uri for serial forking */
            return 1;
        } else {
            ERR("avp_destination:AVP has numeric value\n");
            return -1;
        }
    }
    return -1;
}


static int xlset_destination(struct sip_msg* msg, char* format, char* p2)
{
    str val;
    
    if (xl_printstr(msg, (xl_elog_t*) format, &val.s, &val.len) > 0) {
        DBG("Setting dest to: '%.*s'\n", val.len, val.s);
        if (set_destination(msg, &val) == 0) {
            return 1;
        }
    }
    
    return -1;
}


static int attr_hdr_body2attrs(struct sip_msg* m, char* header_, char* prefix_)
{
    char name_buf[50];
    str *prefix = (str*) prefix_;
    struct hdr_name *header = (void*) header_;
    struct hdr_field *hf;
    str s, name, val;
    int_str name2, val2;
    int val_type, arr;
    if (header->kind == HDR_STR) {
        if (parse_headers(m, HDR_EOH_F, 0) == -1) {
            LOG(L_ERR, "ERROR: attr_hdr_body2attrs: Error while parsing message\n");
            return -1;
        }
        
        for (hf=m->headers; hf; hf=hf->next) {
            if ( (header->name.s.len == hf->name.len)
                 && (!strncasecmp(header->name.s.s, hf->name.s, hf->name.len)) ) {
                break;
            }
        }
    }
    else {
        if (parse_headers(m, header->name.n, 0) == -1) {
            LOG(L_ERR, "ERROR: attr_hdr_body2attrs: Error while parsing message\n");
            return -1;
        }
        switch (header->name.n) {
                 //     HDR_xxx:
        default:
            hf = NULL;
            break;
        }
    }
    if (!hf || !hf->body.len)
        return 1;
    
         // parse body of hf
    s = hf->body;
    name_buf[0] = '\0';
    while (s.len) {
        trim_leading(&s);
        name.s = s.s;
        while ( s.len &&
                ( (s.s[0] >= 'a' && s.s[0] <= 'z') ||
                  (s.s[0] >= 'A' && s.s[0] <= 'Z') ||
                  (s.s[0] >= '0' && s.s[0] <= '9') ||
                  s.s[0] == '_' || s.s[0] == '-'
                  ) ) {
            s.s++;
            s.len--;
        }
        if (s.s == name.s)
            break;
        name.len = s.s - name.s;
        trim_leading(&s);
        if (!s.len)
            break;
        if (s.s[0] == '=') {
            s.s++;
            s.len--;
            arr = -1;
            
            while (s.len) {
                trim_leading(&s);
                val_type = 0;
                if (!s.len)
                    break;
                if (s.s[0] == '"') {
                    s.s++;
                    s.len--;
                    val.s = s.s;
                    
                    s.s = q_memchr(s.s, '\"', s.len);
                    if (!s.s)
                        break;
                    val.len = s.s - val.s;
                    val_type = AVP_VAL_STR;
                    s.s++;
                    s.len -= s.s - val.s;
                }
                else {
                    int r;
                    val.s = s.s;
                    if (s.s[0] == '+' || s.s[0] == '-') {
                        s.s++;
                        s.len--;
                    }
                    val2.n = 0; r = 0;
                    while (s.len) {
                        if (s.s[0] == header->field_delimiter || (header->array_delimiter && header->array_delimiter == s.s[0]))
                            goto token_end;
                        switch (s.s[0]) {
                        case ' ':
                        case '\t':
                        case '\n':
                        case '\r':
                            goto token_end;
                        }
                        if (!val_type && s.s[0] >= '0' && s.s[0]<= '9') {
                            r++;
                            val2.n *= 10;
                            val2.n += s.s[0] - '0';
                                 // overflow detection ???
                        }
                        else {
                            val_type = AVP_VAL_STR;
                        }
                        s.s++;
                        s.len--;
                    }
                token_end:
                    if (r == 0) val_type = AVP_VAL_STR;
                    if (!val_type && val.s[0] == '-') {
                        val2.n = -val2.n;
                    }
                    val.len = s.s - val.s;
                }
                trim_leading(&s);
                if (arr >= 0 || (s.len && header->array_delimiter && header->array_delimiter == s.s[0])) {
                    arr++;
                    if (arr == 100)
                        LOG(L_ERR, "ERROR: avp index out of limit\n");
                }
                if (val.len && arr < 100) {
                    if (prefix != NULL || arr >= 0) {
                        if ((prefix?prefix->len:0)+name.len+1+((arr>=0)?3/*#99*/:0) > sizeof(name_buf)) {
                            if (arr <= 0)
                                LOG(L_ERR, "ERROR: avp name too long\n");
                            goto cont;
                        }
                        name2.s.len = 0;
                        name2.s.s = name_buf;
                        if (prefix != NULL) {
                            if (name_buf[0] == '\0') {
                                memcpy(&name_buf[0], prefix->s, prefix->len);
                            }
                            name2.s.len += prefix->len;
                        }
                        if (arr <= 0) {
                            memcpy(&name_buf[name2.s.len], name.s, name.len);
                        }
                        name2.s.len += name.len;
                        if (arr >= 0) {
                            name_buf[name2.s.len] = '#';
                            name2.s.len++;
                            if (arr >= 10) {
                                name_buf[name2.s.len] = '0'+ (arr / 10);
                                name2.s.len++;
                            }
                            name_buf[name2.s.len] = '0'+ (arr % 10);
                            name2.s.len++;
                        }
                    }
                    else {
                        name2.s.s = name.s;
                        name2.s.len = name.len;
                    }
                    if ( ((val_type & AVP_VAL_STR) && (header->val_types & VAL_TYPE_STR)) ||
                         ((val_type & AVP_VAL_STR) == 0 && (header->val_types & VAL_TYPE_INT))  ) {
                        if (val_type) {
                            val2.s.s = val.s;
                            val2.s.len = val.len;
                            DBG("DEBUG: attr_hdr_body2attrs: adding avp '%.*s', sval: '%.*s'\n", name2.s.len, (char*) name2.s.s, val.len, val.s);
                        } else {
                            DBG("DEBUG: attr_hdr_body2attrs: adding avp '%.*s', ival: '%d'\n", name2.s.len, (char*) name2.s.s, val2.n);
                        }
                        if ( add_avp(AVP_NAME_STR | val_type, name2, val2)!=0) {
                            LOG(L_ERR, "ERROR: attr_hdr_body2attrs: add_avp failed\n");
                            return 1;
                        }
                    }
                }
            cont:
                if (s.len && header->array_delimiter && header->array_delimiter == s.s[0]) {
                    s.s++;
                    s.len--;
                }
                else {
                    break;
                }
            };
        }
        if (s.len && s.s[0] == header->field_delimiter) {
            s.s++;
            s.len--;
        }
        else {
            break;
        }
    }
    return 1;
}


static int attr_hdr_body2attrs2(struct sip_msg* msg, char* header_, char* prefix_) 
{
    return attr_hdr_body2attrs(msg, header_, prefix_);
}


static int attr_hdr_body2attrs_fixup(void** param, int param_no) {
    char *c, *params;
    struct hdr_name *h;
    int n;
    str *s;
    if (param_no == 1) {
        c = *param;
        if (*c == '#') {
            c++;
            n = strtol(c, &params, 10);
            switch (*params) {
            case PARAM_DELIM:
                break;
            case 0:
                params = 0;
                break;
            default:
                LOG(L_ERR, "attr_hdr_body2attrs_fixup: bad AVP value\n");
                return E_CFG;
            }
            switch (n) {
                //                              case HDR_xxx:
                //                              case HDR_xxx:
                //                                      break;
            default:
                LOG(L_ERR, "attr_hdr_body2attrs_fixup: header name is not valid and supported HDR_xxx id '%s' resolved as %d\n", c, n);
                return E_CFG;
            }
            h = pkg_malloc(sizeof(*h));
            if (!h) {
                LOG(L_ERR, "attr_hdr_body2attrs_fixup: out of memory\n");
                return E_OUT_OF_MEM;
            }
            
            h->kind = HDR_ID;
            h->name.n = n;
            pkg_free(*param);
            
        }
        else {
            params = strchr(c, PARAM_DELIM);
            if (params)
                n = params-c;
            else
                n = strlen(c);
            if (n == 0) {
                LOG(L_ERR, "attr_hdr_body2attrs_fixup: header name is empty\n");
                return E_CFG;
            }
            h = pkg_malloc(sizeof(*h)+n+1);
            if (!h) {
                LOG(L_ERR, "attr_hdr_body2attrs_fixup: out of memory\n");
                return E_OUT_OF_MEM;
            }
            h->kind = HDR_STR;
            h->name.s.len = n;
            h->name.s.s = (char *) h + sizeof(*h);
            memcpy(h->name.s.s, c, n+1);
        }
        if (params) {
            h->val_types = 0;
            while (*params) {
                switch (*params) {
                case 'i':
                case 'I':
                    h->val_types = VAL_TYPE_INT;
                    break;
                case 's':
                case 'S':
                    h->val_types = VAL_TYPE_STR;
                    break;
                case PARAM_DELIM:
                    break;
                default:
                    LOG(L_ERR, "attr_hdr_body2attrs_fixup: bad field param modifier near '%s'\n", params);
                    return E_CFG;
                }
                params++;
            }
            if (!h->val_types) {
                LOG(L_ERR, "attr_hdr_body2attrs_fixup: no field param modifier specified\n");
                return E_CFG;
            }
        }
        else {
            h->val_types = VAL_TYPE_INT|VAL_TYPE_STR;
        }
        pkg_free(*param);
        h->field_delimiter = ',';
        h->array_delimiter = '\0';
        
        *param = h;
    }
    else if (param_no == 2) {
        n = strlen(*param);
        if (n == 0) {
            s = NULL;
        }
        else {
            s = pkg_malloc(sizeof(*s)+n+1);
            if (!s) {
                LOG(L_ERR, "attr_hdr_body2attrs_fixup: out of memory\n");
                return E_OUT_OF_MEM;
            }
            s->len = n;
            s->s = (char *) s + sizeof(*s);
            memcpy(s->s, *param, n+1);
        }
        pkg_free(*param);
        *param = s;
    }
    return 0;
}

static int attr_hdr_body2attrs2_fixup(void** param, int param_no) 
{
    struct hdr_name *h;
    int res = attr_hdr_body2attrs_fixup(param, param_no);
    if (res == 0 && param_no == 1) {
        h = *param;
        h->field_delimiter = ';';
        h->array_delimiter = ',';
    }
    return res;
}



static int avpgroup_fixup(void** param, int param_no)
{
    unsigned long flags;
    char* s;
    
    if (param_no == 1) {
             /* Determine the track and class of attributes to be loaded */
        s = (char*)*param;
        flags = 0;
        if (*s != '$' || (strlen(s) != 3 && strlen(s) != 2)) {
            ERR("Invalid parameter value, $xy expected\n");
            return -1;
        }
        switch((s[1] << 8) + s[2]) {
        case 0x4655: /* $fu */
        case 0x6675:
        case 0x4675:
        case 0x6655:
            flags = AVP_TRACK_FROM | AVP_CLASS_USER;
            break;
            
        case 0x4652: /* $fr */
        case 0x6672:
        case 0x4672:
        case 0x6652:
            flags = AVP_TRACK_FROM | AVP_CLASS_URI;
            break;
            
        case 0x5455: /* $tu */
        case 0x7475:
        case 0x5475:
        case 0x7455:
            flags = AVP_TRACK_TO | AVP_CLASS_USER;
            break;
            
        case 0x5452: /* $tr */
        case 0x7472:
        case 0x5472:
        case 0x7452:
            flags = AVP_TRACK_TO | AVP_CLASS_URI;
            break;

        case 0x4644: /* $fd */
        case 0x6664:
        case 0x4664:
        case 0x6644:
            flags = AVP_TRACK_FROM | AVP_CLASS_DOMAIN;
            break;

        case 0x5444: /* $td */
        case 0x7464:
        case 0x5464:
        case 0x7444:
            flags = AVP_TRACK_TO | AVP_CLASS_DOMAIN;
            break;

        case 0x6700: /* $td */
        case 0x4700:
            flags = AVP_CLASS_GLOBAL;
            break;
            
        default:
            ERR("Invalid parameter value: '%s'\n", s);
            return -1;
        }
        
        pkg_free(*param);
        *param = (void*)flags;
        return 1;
    }
    return 0;
}



static int select_attr_fixup(str* res, select_t* s, struct sip_msg* msg)
{
        avp_ident_t *avp_ident;

#define SEL_PARAM_IDX   1

        if (! msg) { /* fixup call */
                str attr_name;
                
                if (s->params[SEL_PARAM_IDX].type != SEL_PARAM_STR) {
                        ERR("attribute name expected.\n");
                        return -1;
                }

                attr_name = s->params[SEL_PARAM_IDX].v.s;
                DEBUG("fix up for attribute '%.*s'\n", STR_FMT(&attr_name));

                if (! (avp_ident = pkg_malloc(sizeof(avp_ident_t)))) {
                        ERR("out of mem; requested: %d.\n", (int)sizeof(avp_ident_t));
                        return -1;
                }
                memset(avp_ident, 0, sizeof(avp_ident_t));

                /* skip leading `$' */
                if ((1 < attr_name.len) && (attr_name.s[0] == '$')) {
                        attr_name.len --;
                        attr_name.s ++;
                }
                if (parse_avp_ident(&attr_name, avp_ident) < 0) {
                        ERR("failed to parse attribute name: `%.*s'.\n", STR_FMT(&attr_name));
                        pkg_free(avp_ident);
                }
                s->params[SEL_PARAM_IDX].v.p = avp_ident;
                s->params[SEL_PARAM_IDX].type = SEL_PARAM_PTR;
        } else { /* run time call */
                avp_t *ret;
                avp_value_t val;

#ifdef EXTRA_DEBUG
                assert(s->params[SEL_PARAM_IDX].type == SEL_PARAM_PTR);
#endif
                avp_ident = s->params[SEL_PARAM_IDX].v.p;
                ret = search_first_avp(avp_ident->flags, avp_ident->name, &val, NULL);
                if (ret && ret->flags & AVP_VAL_STR)
                        *res = val.s;
        }

        return 0;

#undef SEL_PARAM_IDX
}

SELECT_F(select_any_nameaddr)
ABSTRACT_F(select_attr);

select_row_t sel_declaration[] = {
        { NULL, SEL_PARAM_STR, STR_STATIC_INIT("avp"), select_attr, SEL_PARAM_EXPECTED},
        { NULL, SEL_PARAM_STR, STR_STATIC_INIT("attr"), select_attr, SEL_PARAM_EXPECTED},
        { NULL, SEL_PARAM_STR, STR_STATIC_INIT("attribute"), select_attr, SEL_PARAM_EXPECTED},
        { select_attr, SEL_PARAM_STR, STR_NULL, select_attr_fixup, FIXUP_CALL | CONSUME_NEXT_STR},

        { select_attr_fixup, SEL_PARAM_STR, STR_STATIC_INIT("nameaddr"), select_any_nameaddr, NESTED},

        { NULL, SEL_PARAM_INT, STR_NULL, NULL, 0}
};

static int mod_init()
{
        DBG("%s - initializing\n", exports.name);
        return register_select_table(sel_declaration);
}