1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
//go:build linux
package hostos
import (
"fmt"
"os"
"strconv"
"strings"
)
func LocalPortRange() (int, int, error) {
out, err := os.ReadFile("/proc/sys/net/ipv4/ip_local_port_range")
if err != nil {
return 0, 0, fmt.Errorf("hostos: reading /proc/sys/net/ipv4/ip_local_port_range: %w", err)
}
fields := strings.Fields(string(out))
if len(fields) != 2 {
return 0, 0, fmt.Errorf("hostos: /proc/sys/net/ipv4/ip_local_port_range is %q, expected two numbers",
strings.TrimSpace(string(out)))
}
first, err1 := strconv.Atoi(fields[0])
last, err2 := strconv.Atoi(fields[1])
if err1 != nil || err2 != nil {
return 0, 0, fmt.Errorf("hostos: /proc/sys/net/ipv4/ip_local_port_range is %q, expected two numbers",
strings.TrimSpace(string(out)))
}
return first, last, nil
}
