Files
gb-cms/sdp/util.go
2024-10-22 11:25:10 +08:00

99 lines
2.4 KiB
Go

// 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 sdp
import (
"encoding/hex"
"math/rand"
"net"
"strconv"
"strings"
"syscall"
)
// Return true if error is ICMP connection refused.
func IsRefused(err error) bool {
operr, ok := err.(*net.OpError)
return ok && operr.Err == syscall.ECONNREFUSED
}
// Return true if error was caused by reading from a closed socket.
func IsUseOfClosed(err error) bool {
return strings.Contains(err.Error(), "use of closed network connection")
}
// Return true if IP contains a colon.
func IsIPv6(ip string) bool {
return strings.Index(ip, ":") >= 0
}
// Generate a secure random number between 0 and 50,000.
func GenerateCSeq() int {
return rand.Int() % 50000
}
// Generate a 48-bit secure random string like: 27c97271d363.
func GenerateTag() string {
return hex.EncodeToString(randomBytes(6))
}
// Generate a SIP 2.0 Via branch Username. This is probably not suitable for use by
// stateless proxies.
func GenerateBranch() string {
return "z9hG4bK-" + GenerateTag()
}
// Generate a secure UUID4, e.g.f47ac10b-58cc-4372-a567-0e02b2c3d479
func GenerateCallID() string {
lol := randomBytes(15)
digs := hex.EncodeToString(lol)
uuid4 := digs[0:8] +
"-" + digs[8:12] +
"-4" + digs[12:15] +
"-a" + digs[15:18] +
"-" + digs[18:]
return uuid4
}
// Generate a random Username for an SDP.
func GenerateOriginID() string {
return strconv.FormatUint(uint64(rand.Uint32()), 10)
}
func randomBytes(l int) (b []byte) {
b = make([]byte, l)
for i := 0; i < l; i++ {
b[i] = byte(rand.Int())
}
return
}
/*func append(buf []byte, s string) []byte {
lenb, lens := len(buf), len(s)
if lenb+lens <= cap(buf) {
buf = buf[0 : lenb+lens]
} else {
panic("mtu exceeded D:")
}
for i := 0; i < lens; i++ {
buf[lenb+i] = byte(s[i])
}
return buf
}*/
func Portstr(port uint16) string {
return strconv.FormatInt(int64(port), 10)
}