You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
134 lines
3.5 KiB
134 lines
3.5 KiB
// Copyright 2020 Justine Alexandra Roberts Tunney
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package sip
|
|
|
|
import (
|
|
"errors"
|
|
"github.com/jart/gosip/util"
|
|
"log"
|
|
"net"
|
|
)
|
|
|
|
type AddressRoute struct {
|
|
Address string
|
|
Next *AddressRoute
|
|
}
|
|
|
|
func PopulateMessage(via *Via, contact *Addr, msg *Msg) {
|
|
if !msg.IsResponse() {
|
|
if msg.Via == nil {
|
|
msg.Via = via
|
|
}
|
|
if msg.Contact == nil {
|
|
msg.Contact = contact
|
|
}
|
|
if msg.To == nil {
|
|
msg.To = &Addr{Uri: msg.Request}
|
|
}
|
|
if msg.From == nil {
|
|
msg.From = msg.Contact.Copy()
|
|
msg.From.Uri.Param = nil
|
|
}
|
|
if msg.CallID == "" {
|
|
msg.CallID = util.GenerateCallID()
|
|
}
|
|
if msg.CSeq == 0 {
|
|
msg.CSeq = util.GenerateCSeq()
|
|
}
|
|
if msg.CSeqMethod == "" {
|
|
msg.CSeqMethod = msg.Method
|
|
}
|
|
if msg.MaxForwards == 0 {
|
|
msg.MaxForwards = 70
|
|
}
|
|
if msg.UserAgent == "" {
|
|
msg.UserAgent = GosipUA
|
|
}
|
|
if msg.Via.Param.Get("branch") == nil {
|
|
msg.Via.Param = &Param{"branch", util.GenerateBranch(), msg.Via.Param}
|
|
}
|
|
if msg.From.Param.Get("tag") == nil {
|
|
msg.From.Param = &Param{"tag", util.GenerateTag(), msg.From.Param}
|
|
}
|
|
}
|
|
}
|
|
|
|
func RouteMessage(via *Via, contact *Addr, msg *Msg) (host string, port uint16, err error) {
|
|
if msg.IsResponse() {
|
|
if via.CompareHostPort(msg.Via) {
|
|
msg.Via = msg.Via.Next
|
|
}
|
|
host, port = msg.Via.Host, msg.Via.Port
|
|
if received := msg.Via.Param.Get("received"); received != nil {
|
|
host = received.Value
|
|
}
|
|
} else {
|
|
if contact.CompareHostPort(msg.Route) {
|
|
msg.Route = msg.Route.Next
|
|
}
|
|
if msg.Route != nil {
|
|
if msg.Method == "REGISTER" {
|
|
return "", 0, errors.New("Don't route REGISTER requests")
|
|
}
|
|
if msg.Route.Uri.Param.Get("lr") != nil {
|
|
// RFC3261 16.12.1.1 Basic SIP Trapezoid
|
|
host, port = msg.Route.Uri.Host, msg.Route.Uri.Port
|
|
} else {
|
|
// RFC3261 16.12.1.2: Traversing a Strict-Routing Proxy
|
|
msg.Route = msg.Route.Copy()
|
|
msg.Route.Last().Next = &Addr{Uri: msg.Request}
|
|
msg.Request = msg.Route.Uri
|
|
msg.Route = msg.Route.Next
|
|
host, port = msg.Request.Host, msg.Request.Port
|
|
}
|
|
} else {
|
|
host, port = msg.Request.Host, msg.Request.Port
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
func RouteAddress(host string, port uint16, wantSRV bool) (routes *AddressRoute, err error) {
|
|
if net.ParseIP(host) != nil {
|
|
if port == 0 {
|
|
port = 5060
|
|
}
|
|
return &AddressRoute{Address: net.JoinHostPort(host, portstr(port))}, nil
|
|
}
|
|
if port == 0 {
|
|
if wantSRV {
|
|
_, srvs, err := net.LookupSRV("sip", "udp", host)
|
|
if err == nil && len(srvs) > 0 {
|
|
s := ""
|
|
for i := len(srvs) - 1; i >= 0; i-- {
|
|
routes = &AddressRoute{
|
|
Address: net.JoinHostPort(srvs[i].Target, portstr(srvs[i].Port)),
|
|
Next: routes,
|
|
}
|
|
s = " " + routes.Address + s
|
|
}
|
|
log.Printf("%s routes to: %s\r\n", host, s)
|
|
return routes, nil
|
|
}
|
|
log.Printf("net.LookupSRV(sip, udp, %s) failed: %s\r\n", host, err)
|
|
}
|
|
port = 5060
|
|
}
|
|
addr, err := net.ResolveUDPAddr("udp", net.JoinHostPort(host, portstr(port)))
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &AddressRoute{Address: addr.String()}, nil
|
|
}
|