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gometalinter

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This commit is contained in:
Andrey Meshkov
2019-01-24 20:11:01 +03:00
committed by Eugene Bujak
parent c9d627ea71
commit d078851246
21 changed files with 454 additions and 409 deletions
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20
dhcpd/check_other_dhcp.go
View File

@@ -13,6 +13,8 @@ import (
"github.com/krolaw/dhcp4"
)
// CheckIfOtherDHCPServersPresent sends a DHCP request to the specified network interface,
// and waits for a response for a period defined by defaultDiscoverTime
func CheckIfOtherDHCPServersPresent(ifaceName string) (bool, error) {
iface, err := net.InterfaceByName(ifaceName)
if err != nil {
@@ -30,8 +32,8 @@ func CheckIfOtherDHCPServersPresent(ifaceName string) (bool, error) {
dst := "255.255.255.255:67"
// form a DHCP request packet, try to emulate existing client as much as possible
xId := make([]byte, 8)
n, err := rand.Read(xId)
xID := make([]byte, 8)
n, err := rand.Read(xID)
if n != 8 && err == nil {
err = fmt.Errorf("Generated less than 8 bytes")
}
@@ -60,13 +62,13 @@ func CheckIfOtherDHCPServersPresent(ifaceName string) (bool, error) {
leaseTime := uint32(math.RoundToEven(time.Duration(time.Hour * 24 * 90).Seconds()))
binary.BigEndian.PutUint32(leaseTimeRaw, leaseTime)
options := []dhcp4.Option{
{dhcp4.OptionParameterRequestList, requestList},
{dhcp4.OptionMaximumDHCPMessageSize, maxUDPsizeRaw},
{dhcp4.OptionClientIdentifier, append([]byte{0x01}, iface.HardwareAddr...)},
{dhcp4.OptionIPAddressLeaseTime, leaseTimeRaw},
{dhcp4.OptionHostName, []byte(hostname)},
{Code: dhcp4.OptionParameterRequestList, Value: requestList},
{Code: dhcp4.OptionMaximumDHCPMessageSize, Value: maxUDPsizeRaw},
{Code: dhcp4.OptionClientIdentifier, Value: append([]byte{0x01}, iface.HardwareAddr...)},
{Code: dhcp4.OptionIPAddressLeaseTime, Value: leaseTimeRaw},
{Code: dhcp4.OptionHostName, Value: []byte(hostname)},
}
packet := dhcp4.RequestPacket(dhcp4.Discover, iface.HardwareAddr, nil, xId, false, options)
packet := dhcp4.RequestPacket(dhcp4.Discover, iface.HardwareAddr, nil, xID, false, options)
// resolve 0.0.0.0:68
udpAddr, err := net.ResolveUDPAddr("udp4", src)
@@ -98,7 +100,7 @@ func CheckIfOtherDHCPServersPresent(ifaceName string) (bool, error) {
}
// send to 255.255.255.255:67
n, err = c.WriteTo(packet, dstAddr)
_, err = c.WriteTo(packet, dstAddr)
// spew.Dump(n, err)
if err != nil {
return false, wrapErrPrint(err, "Couldn't send a packet to %s", dst)