route.c
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 /*
  * $Id$
  *
  * SIP routing engine
  *
7dd0b342
  *
  * Copyright (C) 2001-2003 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
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  */
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3e429f5c
 #include <stdlib.h>
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 #include <sys/types.h>
 #include <regex.h>
 #include <netdb.h>
 #include <string.h>
a15c363f
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <netdb.h>
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 #include "route.h"
855c2e68
 #include "forward.h"
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 #include "dprint.h"
4ac74c03
 #include "proxy.h"
f20a56a2
 #include "action.h"
34fd2612
 #include "sr_module.h"
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 #include "ip_addr.h"
 #include "resolve.h"
855c2e68
 #include "parser/parse_uri.h"
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03150098
 #ifdef DEBUG_DMALLOC
 #include <dmalloc.h>
 #endif
 
f20a56a2
 /* main routing script table  */
 struct action* rlist[RT_NO];
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 /* reply routing table */
 struct action* reply_rlist[REPLY_RT_NO];
512dcd98
 
 
f20a56a2
 static int fix_actions(struct action* a); /*fwd declaration*/
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a15c363f
 /* traverses an expr tree and compiles the REs where necessary) 
  * returns: 0 for ok, <0 if errors */
3e429f5c
 static int fix_expr(struct expr* exp)
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 {
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 	regex_t* re;
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 	int ret;
a15c363f
 	
f20a56a2
 	ret=E_BUG;
a15c363f
 	if (exp==0){
 		LOG(L_CRIT, "BUG: fix_expr: null pointer\n");
 		return E_BUG;
 	}
 	if (exp->type==EXP_T){
 		switch(exp->op){
 			case AND_OP:
 			case OR_OP:
 						if ((ret=fix_expr(exp->l.expr))!=0)
 							return ret;
 						ret=fix_expr(exp->r.expr);
 						break;
 			case NOT_OP:
 						ret=fix_expr(exp->l.expr);
 						break;
 			default:
 						LOG(L_CRIT, "BUG: fix_expr: unknown op %d\n",
 								exp->op);
 		}
 	}else if (exp->type==ELEM_T){
 			if (exp->op==MATCH_OP){
 				if (exp->subtype==STRING_ST){
 					re=(regex_t*)malloc(sizeof(regex_t));
 					if (re==0){
 						LOG(L_CRIT, "ERROR: fix_expr: memory allocation"
 								" failure\n");
 						return E_OUT_OF_MEM;
 					}
 					if (regcomp(re, (char*) exp->r.param,
 								REG_EXTENDED|REG_NOSUB|REG_ICASE) ){
 						LOG(L_CRIT, "ERROR: fix_expr : bad re \"%s\"\n",
 									(char*) exp->r.param);
 						free(re);
 						return E_BAD_RE;
 					}
 					/* replace the string with the re */
 					free(exp->r.param);
 					exp->r.param=re;
 					exp->subtype=RE_ST;
 				}else if (exp->subtype!=RE_ST){
 					LOG(L_CRIT, "BUG: fix_expr : invalid type for match\n");
 					return E_BUG;
 				}
 			}
f20a56a2
 			if (exp->l.operand==ACTION_O){
 				ret=fix_actions((struct action*)exp->r.param);
 				if (ret!=0){
 					LOG(L_CRIT, "ERROR: fix_expr : fix_actions error\n");
 					return ret;
 				}
 			}
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 			ret=0;
 	}
 	return ret;
 }
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 /* adds the proxies in the proxy list & resolves the hostnames */
f20a56a2
 /* returns 0 if ok, <0 on error */
3e429f5c
 static int fix_actions(struct action* a)
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 {
 	struct action *t;
4ac74c03
 	struct proxy_l* p;
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 	char *tmp;
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 	int ret,r;
 	struct sr_module* mod;
a6982b85
 	str s;
a15c363f
 	
f20a56a2
 	if (a==0){
 		LOG(L_CRIT,"BUG: fix_actions: null pointer\n");
 		return E_BUG;
 	}
a15c363f
 	for(t=a; t!=0; t=t->next){
 		switch(t->type){
 			case FORWARD_T:
0c5da34b
 			case FORWARD_TCP_T:
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 			case FORWARD_UDP_T:
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 			case SEND_T:
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 			case SEND_TCP_T:
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 					switch(t->p1_type){
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 						case IP_ST: 
 							tmp=strdup(ip_addr2a(
 										(struct ip_addr*)t->p1.data));
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 							if (tmp==0){
 								LOG(L_CRIT, "ERROR: fix_actions:"
 										"memory allocation failure\n");
 								return E_OUT_OF_MEM;
 							}
 							t->p1_type=STRING_ST;
 							t->p1.string=tmp;
 							/* no break */
 						case STRING_ST:
a6982b85
 							s.s = t->p1.string;
 							s.len = strlen(s.s);
 							p=add_proxy(&s, t->p2.number);
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 							if (p==0) return E_BAD_ADDRESS;
 							t->p1.data=p;
 							t->p1_type=PROXY_ST;
 							break;
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 						case URIHOST_ST:
 							break;
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 						default:
 							LOG(L_CRIT, "BUG: fix_actions: invalid type"
3e429f5c
 									"%d (should be string or number)\n",
 										t->type);
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 							return E_BUG;
 					}
 					break;
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 			case IF_T:
f20a56a2
 				if (t->p1_type!=EXPR_ST){
 					LOG(L_CRIT, "BUG: fix_actions: invalid subtype"
 								"%d for if (should be expr)\n",
 								t->p1_type);
 					return E_BUG;
 				}else if( (t->p2_type!=ACTIONS_ST)&&(t->p2_type!=NOSUBTYPE) ){
 					LOG(L_CRIT, "BUG: fix_actions: invalid subtype"
 								"%d for if() {...} (should be action)\n",
 								t->p2_type);
 					return E_BUG;
 				}else if( (t->p3_type!=ACTIONS_ST)&&(t->p3_type!=NOSUBTYPE) ){
 					LOG(L_CRIT, "BUG: fix_actions: invalid subtype"
 								"%d for if() {} else{...}(should be action)\n",
 								t->p3_type);
 					return E_BUG;
 				}
 				if (t->p1.data){
 					if ((ret=fix_expr((struct expr*)t->p1.data))<0)
 						return ret;
 				}
 				if ( (t->p2_type==ACTIONS_ST)&&(t->p2.data) ){
 					if ((ret=fix_actions((struct action*)t->p2.data))<0)
 						return ret;
 				}
 				if ( (t->p3_type==ACTIONS_ST)&&(t->p3.data) ){
 						if ((ret=fix_actions((struct action*)t->p3.data))<0)
 						return ret;
 				}
 				break;
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 			case MODULE_T:
 				if ((mod=find_module(t->p1.data, &r))!=0){
 					DBG("fixing %s %s\n", mod->path,
 							mod->exports->cmd_names[r]);
 					if (mod->exports->fixup_pointers[r]){
 						if (mod->exports->param_no[r]>0){
5ada8f8a
 							ret=mod->exports->fixup_pointers[r](&t->p2.data,
 																1);
 							t->p2_type=MODFIXUP_ST;
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 							if (ret<0) return ret;
 						}
 						if (mod->exports->param_no[r]>1){
5ada8f8a
 							ret=mod->exports->fixup_pointers[r](&t->p3.data,
 																2);
 							t->p3_type=MODFIXUP_ST;
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 							if (ret<0) return ret;
 						}
 					}
 				}
 			
a15c363f
 		}
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 	}
a15c363f
 	return 0;
 }
 
512dcd98
 
a15c363f
 
 /* eval_elem helping function, returns str op param */
3e429f5c
 static int comp_str(char* str, void* param, int op, int subtype)
a15c363f
 {
 	int ret;
512dcd98
 	
a15c363f
 	ret=-1;
 	if (op==EQUAL_OP){
 		if (subtype!=STRING_ST){
 			LOG(L_CRIT, "BUG: comp_str: bad type %d, "
 					"string expected\n", subtype);
 			goto error;
 		}
 		ret=(strcasecmp(str, (char*)param)==0);
 	}else if (op==MATCH_OP){
 		if (subtype!=RE_ST){
 			LOG(L_CRIT, "BUG: comp_str: bad type %d, "
 					" RE expected\n", subtype);
 			goto error;
 		}
 		ret=(regexec((regex_t*)param, str, 0, 0, 0)==0);
 	}else{
 		LOG(L_CRIT, "BUG: comp_str: unknown op %d\n", op);
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 		goto error;
 	}
a15c363f
 	return ret;
512dcd98
 	
a15c363f
 error:
 	return -1;
 }
 
 
 
1baa06b5
 /* eval_elem helping function, returns an op param */
4e2fdd79
 static int comp_ip(struct ip_addr* ip, void* param, int op, int subtype)
a15c363f
 {
 	struct hostent* he;
 	char ** h;
 	int ret;
855c2e68
 	str tmp;
a15c363f
 
 	ret=-1;
 	switch(subtype){
 		case NET_ST:
4e2fdd79
 			ret=matchnet(ip, (struct net*) param);
 			/*ret=(a&((struct net*)param)->mask)==((struct net*)param)->ip;*/
a15c363f
 			break;
 		case STRING_ST:
71b44bf0
 		case RE_ST:
a15c363f
 			/* 1: compare with ip2str*/
4e2fdd79
 		/* !!!??? review reminder ( resolve(name) & compare w/ all ips? */
 #if 0
a15c363f
 			ret=comp_str(inet_ntoa(*(struct in_addr*)&a), param, op,
 						subtype);
 			if (ret==1) break;
4e2fdd79
 #endif
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 			/* 2: (slow) rev dns the address
 			 * and compare with all the aliases */
4e2fdd79
 			he=rev_resolvehost(ip);
a15c363f
 			if (he==0){
4e2fdd79
 				DBG( "comp_ip: could not rev_resolve ip address: ");
 				print_ip(ip);
 				DBG("\n");
a15c363f
 				ret=0;
 			}else{
4e2fdd79
 				/*  compare with primary host name */
a15c363f
 				ret=comp_str(he->h_name, param, op, subtype);
 				/* compare with all the aliases */
 				for(h=he->h_aliases; (ret!=1) && (*h); h++){
 					ret=comp_str(*h, param, op, subtype);
 				}
 			}
 			break;
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 		case MYSELF_ST: /* check if it's one of our addresses*/
 			tmp.s=ip_addr2a(ip);
 			tmp.len=strlen(tmp.s);
1baa06b5
 			ret=check_self(&tmp, 0);
855c2e68
 			break;
a15c363f
 		default:
 			LOG(L_CRIT, "BUG: comp_ip: invalid type for "
 						" src_ip or dst_ip (%d)\n", subtype);
 			ret=-1;
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 	}
a15c363f
 	return ret;
 	
 }
 
512dcd98
 
a15c363f
 
a1041efe
 /* returns: 0/1 (false/true) or -1 on error, -127 EXPR_DROP */
3e429f5c
 static int eval_elem(struct expr* e, struct sip_msg* msg)
a15c363f
 {
 
 	int ret;
f20a56a2
 	ret=E_BUG;
a15c363f
 	
 	if (e->type!=ELEM_T){
 		LOG(L_CRIT," BUG: eval_elem: invalid type\n");
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 		goto error;
 	}
a15c363f
 	switch(e->l.operand){
 		case METHOD_O:
f8d46776
 				ret=comp_str(msg->first_line.u.request.method.s, e->r.param,
a15c363f
 								e->op, e->subtype);
 				break;
 		case URI_O:
f8d46776
 				if(msg->new_uri.s){
855c2e68
 					if (e->subtype==MYSELF_ST){
 						if (parse_sip_msg_uri(msg)<0) ret=-1;
1baa06b5
 						else	ret=check_self(&msg->parsed_uri.host,
 									msg->parsed_uri.port_no?
 									msg->parsed_uri.port_no:SIP_PORT);
855c2e68
 					}else{
 						ret=comp_str(msg->new_uri.s, e->r.param,
 										e->op, e->subtype);
 					}
03150098
 				}else{
855c2e68
 					if (e->subtype==MYSELF_ST){
 						if (parse_sip_msg_uri(msg)<0) ret=-1;
1baa06b5
 						else	ret=check_self(&msg->parsed_uri.host,
 									msg->parsed_uri.port_no?
 									msg->parsed_uri.port_no:SIP_PORT);
855c2e68
 					}else{
 						ret=comp_str(msg->first_line.u.request.uri.s,
 										 e->r.param, e->op, e->subtype);
 					}
03150098
 				}
a15c363f
 				break;
 		case SRCIP_O:
f2f969dd
 				ret=comp_ip(&msg->rcv.src_ip, e->r.param, e->op, e->subtype);
a15c363f
 				break;
 		case DSTIP_O:
f2f969dd
 				ret=comp_ip(&msg->rcv.dst_ip, e->r.param, e->op, e->subtype);
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 				break;
f20a56a2
 		case NUMBER_O:
 				ret=!(!e->r.intval); /* !! to transform it in {0,1} */
 				break;
 		case ACTION_O:
a1041efe
 				ret=run_actions( (struct action*)e->r.param, msg);
 				if (ret<=0) ret=(ret==0)?EXPR_DROP:0;
 				else ret=1;
a15c363f
 				break;
 		default:
 				LOG(L_CRIT, "BUG: eval_elem: invalid operand %d\n",
 							e->l.operand);
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 	}
a15c363f
 	return ret;
 error:
 	return -1;
 }
 
 
 
a1041efe
 /* ret= 0/1 (true/false) ,  -1 on error or EXPR_DROP (-127)  */
f20a56a2
 int eval_expr(struct expr* e, struct sip_msg* msg)
a15c363f
 {
 	static int rec_lev=0;
 	int ret;
 	
 	rec_lev++;
 	if (rec_lev>MAX_REC_LEV){
 		LOG(L_CRIT, "ERROR: eval_expr: too many expressions (%d)\n",
 				rec_lev);
 		ret=-1;
 		goto skip;
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 	}
a15c363f
 	
 	if (e->type==ELEM_T){
 		ret=eval_elem(e, msg);
 	}else if (e->type==EXP_T){
 		switch(e->op){
 			case AND_OP:
 				ret=eval_expr(e->l.expr, msg);
 				/* if error or false stop evaluating the rest */
 				if (ret!=1) break;
 				ret=eval_expr(e->r.expr, msg); /*ret1 is 1*/
 				break;
 			case OR_OP:
 				ret=eval_expr(e->l.expr, msg);
 				/* if true or error stop evaluating the rest */
 				if (ret!=0) break;
 				ret=eval_expr(e->r.expr, msg); /* ret1 is 0 */
 				break;
 			case NOT_OP:
 				ret=eval_expr(e->l.expr, msg);
 				if (ret<0) break;
 				ret= ! ret;
 				break;
 			default:
 				LOG(L_CRIT, "BUG: eval_expr: unknown op %d\n", e->op);
 				ret=-1;
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 		}
a15c363f
 	}else{
 		LOG(L_CRIT, "BUG: eval_expr: unknown type %d\n", e->type);
 		ret=-1;
512dcd98
 	}
9a3dc64b
 
a15c363f
 skip:
 	rec_lev--;
 	return ret;
 }
 
 
f20a56a2
 /* adds an action list to head; a must be null terminated (last a->next=0))*/
 void push(struct action* a, struct action** head)
 {
 	struct action *t;
 	if (*head==0){
 		*head=a;
 		return;
 	}
 	for (t=*head; t->next;t=t->next);
 	t->next=a;
 }
 
 
a15c363f
 
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f20a56a2
 int add_actions(struct action* a, struct action** head)
a15c363f
 {
 	int ret;
512dcd98
 
f20a56a2
 	LOG(L_DBG, "add_actions: fixing actions...\n");
3e429f5c
 	if ((ret=fix_actions(a))!=0) goto error;
f20a56a2
 	push(a,head);
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 	return 0;
 	
 error:
a15c363f
 	return ret;
512dcd98
 }
 
 
 
f20a56a2
 /* fixes all action tables */
 /* returns 0 if ok , <0 on error */
 int fix_rls()
512dcd98
 {
f20a56a2
 	int i,ret;
 	for(i=0;i<RT_NO;i++){
 		if(rlist[i]){
 			if ((ret=fix_actions(rlist[i]))!=0){
 				return ret;
 			}
 		}
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 	}
caf80ae6
 	for(i=0;i<REPLY_RT_NO;i++){
 		if(reply_rlist[i]){
 			if ((ret=fix_actions(reply_rlist[i]))!=0){
 				return ret;
 			}
 		}
 	}
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 	return 0;
 }
 
 
 /* debug function, prints main routing table */
 void print_rl()
 {
f20a56a2
 	struct action* t;
512dcd98
 	int i,j;
 
3e429f5c
 	for(j=0; j<RT_NO; j++){
 		if (rlist[j]==0){
7268726e
 			if (j==0) DBG("WARNING: the main routing table is empty\n");
3e429f5c
 			continue;
 		}
7268726e
 		DBG("routing table %d:\n",j);
3e429f5c
 		for (t=rlist[j],i=0; t; i++, t=t->next){
f20a56a2
 			print_action(t);
3e429f5c
 		}
f20a56a2
 		DBG("\n");
512dcd98
 	}
caf80ae6
 	for(j=0; j<REPLY_RT_NO; j++){
 		if (reply_rlist[j]==0){
 			if (j==0) DBG("WARNING: the main reply routing table is empty\n");
 			continue;
 		}
 		DBG("routing table %d:\n",j);
 		for (t=reply_rlist[j],i=0; t; i++, t=t->next){
 			print_action(t);
 		}
 		DBG("\n");
 	}
512dcd98
 }