/* iterates over a naptr rr list, returning each time a "good" naptr record
* is found.( srv type, no regex and a supported protocol)
* params:
* naptr_head - naptr rr list head
* tried - bitmap used to keep track of the already tried records
* (no more then sizeof(tried)*8 valid records are
* ever walked
* srv_name - if succesfull, it will be set to the selected record
* srv name (naptr repl.)
* proto - if succesfull it will be set to the selected record
* protocol
* returns 0 if no more records found or a pointer to the selected record
* and sets protocol and srv_name
* WARNING: when calling first time make sure you run first
* naptr_iterate_init(&tried)
*/
struct rdata* naptr_sip_iterate(struct rdata* naptr_head,
naptr_bmp_t* tried,
str* srv_name, char* proto)
{
int i, idx;
struct rdata* l;
struct rdata* l_saved;
struct naptr_rdata* naptr;
struct naptr_rdata* naptr_saved;
char saved_proto;
char naptr_proto;
idx=0;
naptr_proto=PROTO_NONE;
naptr_saved=0;
l_saved=0;
saved_proto=0;
i=0;
for(l=naptr_head; l && (i<MAX_NAPTR_RRS); l=l->next){
if (l->type!=T_NAPTR) continue;
naptr=(struct naptr_rdata*) l->rdata;
if (naptr==0){
LOG(L_CRIT, "naptr_iterate: BUG: null rdata\n");
goto end;
}
/* check if valid and get proto */
if ((naptr_proto=naptr_get_sip_proto(naptr))<=0) continue;
if (*tried& (1<<i)){
i++;
continue; /* already tried */
}
#ifdef NAPTR_DBG
DBG("naptr_iterate: found a valid sip NAPTR rr %.*s,"
" proto %d\n", naptr->repl_len, naptr->repl,
(int)naptr_proto);
#endif
if ((naptr_proto_supported(naptr_proto))){
if (naptr_choose(&naptr_saved, &saved_proto,
naptr, naptr_proto))
idx=i;
l_saved=l;
}
i++;
}
if (naptr_saved){
/* found something */
#ifdef NAPTR_DBG
DBG("naptr_iterate: choosed NAPTR rr %.*s, proto %d"
" tried: 0x%x\n", naptr_saved->repl_len,
naptr_saved->repl, (int)saved_proto, *tried);
#endif
*tried|=1<<idx;
*proto=saved_proto;
srv_name->s=naptr_saved->repl;
srv_name->len=naptr_saved->repl_len;
return l_saved;
}
end:
return 0;
}
size_t create_srv_pref_list(char *proto, struct dns_srv_proto *list) {
struct dns_srv_proto tmp;
size_t i,j,list_len;
int default_order,max;
/* if proto available, then add only the forced protocol to the list */
if (proto && *proto!=PROTO_NONE){
list[0].proto=*proto;
list_len=1;
} else {
list_len = 0;
/*get protocols and preference scores, and add availble protocol(s) and score(s) to the list*/
for (i=PROTO_UDP; i<PROTO_LAST;i++) {
tmp.proto_pref = srv_proto_pref_score(i);
/* if -1 so disabled continue with next protocol*/
if (naptr_proto_supported(i) == 0) {
continue;
} else {
list[i-1].proto_pref=tmp.proto_pref;
list[i-1].proto=i;
list_len++;
}
};
/* if all protocol prefence scores equal, then set the perference to default values: udp,tcp,tls,sctp */
for (i=1; i<list_len;i++) {
if(list[0].proto_pref!=list[i].proto_pref){
default_order=0;
}
}
if (default_order){
for (i=0; i<list_len;i++) {
list[i].proto_pref=srv_proto_pref_score(i);
}
}
/* sorting the list */
for (i=0;i<list_len-1;i++) {
max=i;
for (j=i+1;j<list_len;j++) {
if (list[j].proto_pref>list[max].proto_pref) {
max=j;
}
}
if (i!=max) {
tmp=list[i];
list[i]=list[max];
list[max]=tmp;
}
}
}
return list_len;
}
struct hostent* no_naptr_srv_sip_resolvehost(str* name, unsigned short* port, char* proto)
{
struct dns_srv_proto_t {
char proto;
int proto_pref;
} srv_proto_list[PROTO_LAST], tmp_srv_element;
struct hostent* he;
struct ip_addr* ip;
str srv_name;
static char tmp_srv[MAX_DNS_NAME]; /* tmp. buff. for SRV lookups */
int len;
unsigned char i,j,max,default_order=0,list_len=0;
/* init variables */
he=0;
len=0;
/* check if it's an ip address */
if (((ip=str2ip(name))!=0)
#ifdef USE_IPV6
|| ((ip=str2ip6(name))!=0)
#endif
){
/* we are lucky, this is an ip address */
/* set proto if needed - default udp */
if ((proto)&&(*proto==PROTO_NONE))
*proto=PROTO_UDP;
/* set port if needed - default 5060/5061 */
if ((port)&&(*port==0))
*port=((proto) && (*proto==PROTO_TLS))?SIPS_PORT:SIP_PORT;
he=ip_addr2he(name, ip);
return he;
}
if ((name->len+SRV_MAX_PREFIX_LEN+1)>MAX_DNS_NAME){
LOG(L_WARN, "WARNING: no_naptr_srv_sip_resolvehost: domain name too long"
" (%d), unable to perform SRV lookup\n", name->len);
} else {
/* if proto available, then add only the forced protocol to the list */
if (proto && *proto!=PROTO_NONE){
srv_proto_list[0].proto=*proto;
list_len=1;
} else {
/*get protocols and preference scores, and add availble protocol(s) and score(s) to the list*/
for (i=PROTO_UDP; i<PROTO_LAST;i++) {
tmp_srv_element.proto_pref = proto_pref_score(i);
/* if -1 so disabled continue with next protocol*/
if (naptr_proto_supported(i) == 0 ) {
continue;
} else {
srv_proto_list[i-1].proto_pref=tmp_srv_element.proto_pref;
srv_proto_list[i-1].proto=i;
list_len++;
}
};
/* if all protocol prefence scores equal, then set the perference to default values: udp,tcp,tls,sctp */
for (i=1; i<list_len;i++) {
if(srv_proto_list[0].proto_pref!=srv_proto_list[i].proto_pref){
default_order=0;
}
}
if (default_order){
for (i=0; i<list_len;i++) {
switch ( srv_proto_list[i].proto) {
case PROTO_UDP:
srv_proto_list[i].proto_pref=4;
break;
case PROTO_TCP:
srv_proto_list[i].proto_pref=3;
break;
case PROTO_TLS:
srv_proto_list[i].proto_pref=2;
break;
case PROTO_SCTP:
srv_proto_list[i].proto_pref=1;
break;
}
}
}
/* sorting the list */
for (i=0;i<list_len-1;i++) {
max=i;
for (j=i+1;j<list_len;j++) {
if (srv_proto_list[j].proto_pref>srv_proto_list[max].proto_pref) {
max=j;
}
}
if (i!=max) {
tmp_srv_element=srv_proto_list[i];
srv_proto_list[i]=srv_proto_list[max];
srv_proto_list[max]=tmp_srv_element;
}
}
}
/* looping on the ordered list until we found a protocol what has srv record */
for (i=0; i<list_len;i++) {
switch (srv_proto_list[i].proto) {
case PROTO_NONE: /* no proto specified, use udp */
if (proto)
*proto=PROTO_UDP;
/* no break */
case PROTO_UDP:
memcpy(tmp_srv, SRV_UDP_PREFIX, SRV_UDP_PREFIX_LEN);
memcpy(tmp_srv+SRV_UDP_PREFIX_LEN, name->s, name->len);
tmp_srv[SRV_UDP_PREFIX_LEN + name->len] = '\0';
len=SRV_UDP_PREFIX_LEN + name->len;
break;
case PROTO_TCP:
memcpy(tmp_srv, SRV_TCP_PREFIX, SRV_TCP_PREFIX_LEN);
memcpy(tmp_srv+SRV_TCP_PREFIX_LEN, name->s, name->len);
tmp_srv[SRV_TCP_PREFIX_LEN + name->len] = '\0';
len=SRV_TCP_PREFIX_LEN + name->len;
break;
case PROTO_TLS:
memcpy(tmp_srv, SRV_TLS_PREFIX, SRV_TLS_PREFIX_LEN);
memcpy(tmp_srv+SRV_TLS_PREFIX_LEN, name->s, name->len);
tmp_srv[SRV_TLS_PREFIX_LEN + name->len] = '\0';
len=SRV_TLS_PREFIX_LEN + name->len;
break;
case PROTO_SCTP:
memcpy(tmp_srv, SRV_SCTP_PREFIX, SRV_SCTP_PREFIX_LEN);
memcpy(tmp_srv+SRV_SCTP_PREFIX_LEN, name->s, name->len);
tmp_srv[SRV_SCTP_PREFIX_LEN + name->len] = '\0';
len=SRV_SCTP_PREFIX_LEN + name->len;
break;
default:
LOG(L_CRIT, "BUG: sip_resolvehost: unknown proto %d\n",
(int)srv_proto_list[i].proto);
return 0;
}
/* set default port */
if ((port)&&(*port==0)){
*port=(srv_proto_list[i].proto==PROTO_TLS)?SIPS_PORT:SIP_PORT; /* just in case we don't find another */
}
srv_name.s=tmp_srv;
srv_name.len=len;
#ifdef USE_DNS_CACHE
he=dns_srv_get_he(&srv_name, port, dns_flags);
#else
he=srv_sip_resolvehost(&srv_name, 0, port, proto, 1, 0);
#endif
if (he!=0) {
return he;
}
}
}
return 0;
}
