reply.c

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/*
 * $Id: reply.c 5599 2009-02-12 19:18:14Z miconda $
 *
 * Send a reply
 *
 * Copyright (C) 2001-2003 FhG Fokus
 *
 * This file is part of Kamailio, a free SIP server.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * History:
 * --------
 * 2003-01-18: buffer overflow patch committed (Jan on behalf of Maxim)
 * 2003-01-21: Errors reported via Error-Info header field - janakj
 * 2003-09-11: updated to new build_lump_rpl() interface (bogdan)
 * 2003-11-11: build_lump_rpl() removed, add_lump_rpl() has flags (bogdan)
 */

/*!
 * \file
 * \brief SIP registrar module - Send a reply
 * \ingroup registrar   
 */  

#include <stdio.h>
#include "../../ut.h"
#include "../../parser/msg_parser.h"
#include "../../parser/parse_supported.h"
#include "../../data_lump_rpl.h"
#include "../usrloc/usrloc.h"
#include "rerrno.h"
#include "reg_mod.h"
#include "regtime.h"
#include "reply.h"


#define MAX_CONTACT_BUFFER 1024

#define E_INFO "P-Registrar-Error: "
#define E_INFO_LEN (sizeof(E_INFO) - 1)

#define CONTACT_BEGIN "Contact: "
#define CONTACT_BEGIN_LEN (sizeof(CONTACT_BEGIN) - 1)

#define Q_PARAM ";q="
#define Q_PARAM_LEN (sizeof(Q_PARAM) - 1)

#define EXPIRES_PARAM ";expires="
#define EXPIRES_PARAM_LEN (sizeof(EXPIRES_PARAM) - 1)

#define CONTACT_SEP ", "
#define CONTACT_SEP_LEN (sizeof(CONTACT_SEP) - 1)


/*! \brief
 * Buffer for Contact header field
 */
static struct {
   char* buf;
   int buf_len;
   int data_len;
} contact = {0, 0, 0};


/*! \brief
 * Calculate the length of buffer needed to
 * print contacts
 */
static inline unsigned int calc_buf_len(ucontact_t* c)
{
   unsigned int len;
   int qlen;

   len = 0;
   while(c) {
      if (VALID_CONTACT(c, act_time)) {
         if (len) len += CONTACT_SEP_LEN;
         len += 2 /* < > */ + c->c.len;
         qlen = len_q(c->q);
         if (qlen) len += Q_PARAM_LEN + qlen;
         len += EXPIRES_PARAM_LEN + INT2STR_MAX_LEN;
         if (c->received.s) {
            len += 1 /* ; */ 
               + rcv_param.len 
               + 1 /* = */ 
               + 1 /* dquote */ 
               + c->received.len
               + 1 /* dquote */
               ;
         }
      }
      c = c->next;
   }

   if (len) len += CONTACT_BEGIN_LEN + CRLF_LEN;
   return len;
}


/*! \brief
 * Allocate a memory buffer and print Contact
 * header fields into it
 */
int build_contact(ucontact_t* c)
{
   char *p, *cp;
   int fl, len;

   contact.data_len = calc_buf_len(c);
   if (!contact.data_len) return 0;

   if (!contact.buf || (contact.buf_len < contact.data_len)) {
      if (contact.buf) pkg_free(contact.buf);
      contact.buf = (char*)pkg_malloc(contact.data_len);
      if (!contact.buf) {
         contact.data_len = 0;
         contact.buf_len = 0;
         LM_ERR("no pkg memory left\n");
         return -1;
      } else {
         contact.buf_len = contact.data_len;
      }
   }

   p = contact.buf;
   
   memcpy(p, CONTACT_BEGIN, CONTACT_BEGIN_LEN);
   p += CONTACT_BEGIN_LEN;

   fl = 0;
   while(c) {
      if (VALID_CONTACT(c, act_time)) {
         if (fl) {
            memcpy(p, CONTACT_SEP, CONTACT_SEP_LEN);
            p += CONTACT_SEP_LEN;
         } else {
            fl = 1;
         }

         *p++ = '<';
         memcpy(p, c->c.s, c->c.len);
         p += c->c.len;
         *p++ = '>';

         len = len_q(c->q);
         if (len) {
            memcpy(p, Q_PARAM, Q_PARAM_LEN);
            p += Q_PARAM_LEN;
            memcpy(p, q2str(c->q, 0), len);
            p += len;
         }

         memcpy(p, EXPIRES_PARAM, EXPIRES_PARAM_LEN);
         p += EXPIRES_PARAM_LEN;
         cp = int2str((int)(c->expires - act_time), &len);
         memcpy(p, cp, len);
         p += len;

         if (c->received.s) {
            *p++ = ';';
            memcpy(p, rcv_param.s, rcv_param.len);
            p += rcv_param.len;
            *p++ = '=';
            *p++ = '\"';
            memcpy(p, c->received.s, c->received.len);
            p += c->received.len;
            *p++ = '\"';
         }
      }

      c = c->next;
   }

   memcpy(p, CRLF, CRLF_LEN);
   p += CRLF_LEN;

   contact.data_len = p - contact.buf;

   LM_DBG("created Contact HF: %.*s\n", contact.data_len, contact.buf);
   return 0;
}


#define MSG_200 "OK"
#define MSG_400 "Bad Request"
#define MSG_420 "Bad Extension"
#define MSG_500 "Server Internal Error"
#define MSG_503 "Service Unavailable"

#define EI_R_FINE       "No problem"                                /* R_FINE */
#define EI_R_UL_DEL_R   "usrloc_record_delete failed"               /* R_UL_DEL_R */
#define  EI_R_UL_GET_R   "usrloc_record_get failed"                  /* R_UL_GET */
#define  EI_R_UL_NEW_R   "usrloc_record_new failed"                  /* R_UL_NEW_R */
#define  EI_R_INV_CSEQ   "Invalid CSeq number"                       /* R_INV_CSEQ */
#define  EI_R_UL_INS_C   "usrloc_contact_insert failed"              /* R_UL_INS_C */
#define  EI_R_UL_INS_R   "usrloc_record_insert failed"               /* R_UL_INS_R */
#define  EI_R_UL_DEL_C   "usrloc_contact_delete failed"              /* R_UL_DEL_C */
#define  EI_R_UL_UPD_C   "usrloc_contact_update failed"              /* R_UL_UPD_C */
#define  EI_R_TO_USER    "No username in To URI"                     /* R_TO_USER */
#define  EI_R_AOR_LEN    "Address Of Record too long"                /* R_AOR_LEN */
#define  EI_R_AOR_PARSE  "Error while parsing AOR"                   /* R_AOR_PARSE */
#define  EI_R_INV_EXP    "Invalid expires param in contact"          /* R_INV_EXP */
#define  EI_R_INV_Q      "Invalid q param in contact"                /* R_INV_Q */
#define  EI_R_PARSE      "Message parse error"                       /* R_PARSE */
#define  EI_R_TO_MISS    "To header not found"                       /* R_TO_MISS */
#define  EI_R_CID_MISS   "Call-ID header not found"                  /* R_CID_MISS */
#define  EI_R_CS_MISS    "CSeq header not found"                     /* R_CS_MISS */ 
#define  EI_R_PARSE_EXP "Expires parse error"                       /* R_PARSE_EXP */
#define  EI_R_PARSE_CONT   "Contact parse error"                       /* R_PARSE_CONT */
#define  EI_R_STAR_EXP  "* used in contact and expires is not zero" /* R_STAR__EXP */
#define  EI_R_STAR_CONT "* used in contact and more than 1 contact" /* R_STAR_CONT */
#define  EI_R_OOO "Out of order request"                      /* R_OOO */
#define  EI_R_RETRANS   "Retransmission"                            /* R_RETRANS */
#define EI_R_UNESCAPE   "Error while unescaping username"           /* R_UNESCAPE */
#define EI_R_TOO_MANY   "Too many registered contacts"              /* R_TOO_MANY */
#define EI_R_CONTACT_LEN  "Contact/received too long"               /* R_CONTACT_LEN */
#define EI_R_CALLID_LEN  "Callid too long"                          /* R_CALLID_LEN */
#define EI_R_PARSE_PATH  "Path parse error"                         /* R_PARSE_PATH */
#define EI_R_PATH_UNSUP  "No support for found Path indicated"      /* R_PATH_UNSUP */

str error_info[] = {
   {EI_R_FINE,       sizeof(EI_R_FINE) - 1},
   {EI_R_UL_DEL_R,   sizeof(EI_R_UL_DEL_R) - 1},
   {EI_R_UL_GET_R,   sizeof(EI_R_UL_GET_R) - 1},
   {EI_R_UL_NEW_R,   sizeof(EI_R_UL_NEW_R) - 1},
   {EI_R_INV_CSEQ,   sizeof(EI_R_INV_CSEQ) - 1},
   {EI_R_UL_INS_C,   sizeof(EI_R_UL_INS_C) - 1},
   {EI_R_UL_INS_R,   sizeof(EI_R_UL_INS_R) - 1},
   {EI_R_UL_DEL_C,   sizeof(EI_R_UL_DEL_C) - 1},
   {EI_R_UL_UPD_C,   sizeof(EI_R_UL_UPD_C) - 1},
   {EI_R_TO_USER,    sizeof(EI_R_TO_USER) - 1},
   {EI_R_AOR_LEN,    sizeof(EI_R_AOR_LEN) - 1},
   {EI_R_AOR_PARSE,  sizeof(EI_R_AOR_PARSE) - 1},
   {EI_R_INV_EXP,    sizeof(EI_R_INV_EXP) - 1},
   {EI_R_INV_Q,      sizeof(EI_R_INV_Q) - 1},
   {EI_R_PARSE,      sizeof(EI_R_PARSE) - 1},
   {EI_R_TO_MISS,    sizeof(EI_R_TO_MISS) - 1},
   {EI_R_CID_MISS,   sizeof(EI_R_CID_MISS) - 1},
   {EI_R_CS_MISS,    sizeof(EI_R_CS_MISS) - 1},
   {EI_R_PARSE_EXP,  sizeof(EI_R_PARSE_EXP) - 1},
   {EI_R_PARSE_CONT, sizeof(EI_R_PARSE_CONT) - 1},
   {EI_R_STAR_EXP,   sizeof(EI_R_STAR_EXP) - 1},
   {EI_R_STAR_CONT,  sizeof(EI_R_STAR_CONT) - 1},
   {EI_R_OOO,        sizeof(EI_R_OOO) - 1},
   {EI_R_RETRANS,    sizeof(EI_R_RETRANS) - 1},
   {EI_R_UNESCAPE,   sizeof(EI_R_UNESCAPE) - 1},
   {EI_R_TOO_MANY,   sizeof(EI_R_TOO_MANY) - 1},
   {EI_R_CONTACT_LEN,sizeof(EI_R_CONTACT_LEN) - 1},
   {EI_R_CALLID_LEN, sizeof(EI_R_CALLID_LEN) - 1},
   {EI_R_PARSE_PATH, sizeof(EI_R_PARSE_PATH) - 1},
   {EI_R_PATH_UNSUP, sizeof(EI_R_PATH_UNSUP) - 1}

};

int codes[] = {
   200, /* R_FINE */
   500, /* R_UL_DEL_R */
   500, /* R_UL_GET */
   500, /* R_UL_NEW_R */
   400, /* R_INV_CSEQ */
   500, /* R_UL_INS_C */
   500, /* R_UL_INS_R */
   500, /* R_UL_DEL_C */
   500, /* R_UL_UPD_C */
   400, /* R_TO_USER */
   500, /* R_AOR_LEN */
   400, /* R_AOR_PARSE */
   400, /* R_INV_EXP */
   400, /* R_INV_Q */
   400, /* R_PARSE */
   400, /* R_TO_MISS */
   400, /* R_CID_MISS */
   400, /* R_CS_MISS */
   400, /* R_PARSE_EXP */
   400, /* R_PARSE_CONT */
   400, /* R_STAR_EXP */
   400, /* R_STAR_CONT */
   200, /* R_OOO */
   200, /* R_RETRANS */
   400, /* R_UNESCAPE */
   503, /* R_TOO_MANY */
   400, /* R_CONTACT_LEN */
   400, /* R_CALLID_LEN */
   400, /* R_PARSE_PATH */
   420  /* R_PATH_UNSUP */

};


#define RETRY_AFTER "Retry-After: "
#define RETRY_AFTER_LEN (sizeof(RETRY_AFTER) - 1)

static int add_retry_after(struct sip_msg* _m)
{
   char* buf, *ra_s;
   int ra_len;
   
   ra_s = int2str(retry_after, &ra_len);
   buf = (char*)pkg_malloc(RETRY_AFTER_LEN + ra_len + CRLF_LEN);
   if (!buf) {
      LM_ERR("no pkg memory left\n");
      return -1;
   }
   memcpy(buf, RETRY_AFTER, RETRY_AFTER_LEN);
   memcpy(buf + RETRY_AFTER_LEN, ra_s, ra_len);
   memcpy(buf + RETRY_AFTER_LEN + ra_len, CRLF, CRLF_LEN);
   add_lump_rpl(_m, buf, RETRY_AFTER_LEN + ra_len + CRLF_LEN,
           LUMP_RPL_HDR | LUMP_RPL_NODUP);
   return 0;
}

#define PATH "Path: "
#define PATH_LEN (sizeof(PATH) - 1)

static int add_path(struct sip_msg* _m, str* _p)
{
   char* buf;

   buf = (char*)pkg_malloc(PATH_LEN + _p->len + CRLF_LEN);
   if (!buf) {
      LM_ERR("no pkg memory left\n");
      return -1;
   }
   memcpy(buf, PATH, PATH_LEN);
   memcpy(buf + PATH_LEN, _p->s, _p->len);
   memcpy(buf + PATH_LEN + _p->len, CRLF, CRLF_LEN);
   add_lump_rpl(_m, buf, PATH_LEN + _p->len + CRLF_LEN,
           LUMP_RPL_HDR | LUMP_RPL_NODUP);
   return 0;
}

#define UNSUPPORTED "Unsupported: "
#define UNSUPPORTED_LEN (sizeof(UNSUPPORTED) - 1)

static int add_unsupported(struct sip_msg* _m, str* _p)
{
   char* buf;

   buf = (char*)pkg_malloc(UNSUPPORTED_LEN + _p->len + CRLF_LEN);
   if (!buf) {
      LM_ERR("no pkg memory left\n");
      return -1;
   }
   memcpy(buf, UNSUPPORTED, UNSUPPORTED_LEN);
   memcpy(buf + UNSUPPORTED_LEN, _p->s, _p->len);
   memcpy(buf + UNSUPPORTED_LEN + _p->len, CRLF, CRLF_LEN);
   add_lump_rpl(_m, buf, UNSUPPORTED_LEN + _p->len + CRLF_LEN,
           LUMP_RPL_HDR | LUMP_RPL_NODUP);
   return 0;
}
 
/*! \brief
 * Send a reply
 */
int send_reply(struct sip_msg* _m)
{
   str unsup = str_init(SUPPORTED_PATH_STR);
   long code;
   str msg = str_init(MSG_200); /* makes gcc shut up */
   char* buf;

   if (contact.data_len > 0) {
      add_lump_rpl( _m, contact.buf, contact.data_len, LUMP_RPL_HDR|LUMP_RPL_NODUP|LUMP_RPL_NOFREE);
      contact.data_len = 0;
   }
         
   if (rerrno == R_FINE && path_enabled && _m->path_vec.s) {
      if (path_mode != PATH_MODE_OFF) {
         if (parse_supported(_m)<0 && path_mode == PATH_MODE_STRICT) {
            rerrno = R_PATH_UNSUP;
            if (add_unsupported(_m, &unsup) < 0)
               return -1;
            if (add_path(_m, &_m->path_vec) < 0)
               return -1;
         }
         else if (get_supported(_m) & F_SUPPORTED_PATH) {
            if (add_path(_m, &_m->path_vec) < 0)
               return -1;
         } else if (path_mode == PATH_MODE_STRICT) {
            rerrno = R_PATH_UNSUP;
            if (add_unsupported(_m, &unsup) < 0)
               return -1;
            if (add_path(_m, &_m->path_vec) < 0)
               return -1;
         }
      }
   }

   code = codes[rerrno];
   switch(code) {
   case 200: msg.s = MSG_200; msg.len = sizeof(MSG_200)-1; break;
   case 400: msg.s = MSG_400; msg.len = sizeof(MSG_400)-1;break;
   case 420: msg.s = MSG_420; msg.len = sizeof(MSG_420)-1;break;
   case 500: msg.s = MSG_500; msg.len = sizeof(MSG_500)-1;break;
   case 503: msg.s = MSG_503; msg.len = sizeof(MSG_503)-1;break;
   }
   
   if (code != 200) {
      buf = (char*)pkg_malloc(E_INFO_LEN + error_info[rerrno].len + CRLF_LEN + 1);
      if (!buf) {
         LM_ERR("no pkg memory left\n");
         return -1;
      }
      memcpy(buf, E_INFO, E_INFO_LEN);
      memcpy(buf + E_INFO_LEN, error_info[rerrno].s, error_info[rerrno].len);
      memcpy(buf + E_INFO_LEN + error_info[rerrno].len, CRLF, CRLF_LEN);
      add_lump_rpl( _m, buf, E_INFO_LEN + error_info[rerrno].len + CRLF_LEN,
         LUMP_RPL_HDR|LUMP_RPL_NODUP);

      if (code >= 500 && code < 600 && retry_after) {
         if (add_retry_after(_m) < 0) {
            return -1;
         }
      } 
   }
   
   if (slb.send_reply(_m, code, &msg) == -1) {
      LM_ERR("failed to send %ld %.*s\n", code, msg.len,msg.s);
      return -1;
   } else return 0;
}


/*! \brief
 * Release contact buffer if any
 */
void free_contact_buf(void)
{
   if (contact.buf) {
      pkg_free(contact.buf);
      contact.buf = 0;
      contact.buf_len = 0;
      contact.data_len = 0;
   }
}