open-consul/agent/consul/util.go

314 lines
6.9 KiB
Go

package consul
import (
"encoding/binary"
"fmt"
"net"
"runtime"
"strconv"
"github.com/hashicorp/consul/agent/metadata"
"github.com/hashicorp/go-version"
"github.com/hashicorp/serf/serf"
)
/*
* Contains an entry for each private block:
* 10.0.0.0/8
* 100.64.0.0/10
* 127.0.0.0/8
* 169.254.0.0/16
* 172.16.0.0/12
* 192.168.0.0/16
*/
var privateBlocks []*net.IPNet
func init() {
// Add each private block
privateBlocks = make([]*net.IPNet, 6)
_, block, err := net.ParseCIDR("10.0.0.0/8")
if err != nil {
panic(fmt.Sprintf("Bad cidr. Got %v", err))
}
privateBlocks[0] = block
_, block, err = net.ParseCIDR("100.64.0.0/10")
if err != nil {
panic(fmt.Sprintf("Bad cidr. Got %v", err))
}
privateBlocks[1] = block
_, block, err = net.ParseCIDR("127.0.0.0/8")
if err != nil {
panic(fmt.Sprintf("Bad cidr. Got %v", err))
}
privateBlocks[2] = block
_, block, err = net.ParseCIDR("169.254.0.0/16")
if err != nil {
panic(fmt.Sprintf("Bad cidr. Got %v", err))
}
privateBlocks[3] = block
_, block, err = net.ParseCIDR("172.16.0.0/12")
if err != nil {
panic(fmt.Sprintf("Bad cidr. Got %v", err))
}
privateBlocks[4] = block
_, block, err = net.ParseCIDR("192.168.0.0/16")
if err != nil {
panic(fmt.Sprintf("Bad cidr. Got %v", err))
}
privateBlocks[5] = block
}
// CanServersUnderstandProtocol checks to see if all the servers in the given
// list understand the given protocol version. If there are no servers in the
// list then this will return false.
func CanServersUnderstandProtocol(members []serf.Member, version uint8) (bool, error) {
numServers, numWhoGrok := 0, 0
for _, m := range members {
if m.Tags["role"] != "consul" {
continue
}
numServers++
vsn_min, err := strconv.Atoi(m.Tags["vsn_min"])
if err != nil {
return false, err
}
vsn_max, err := strconv.Atoi(m.Tags["vsn_max"])
if err != nil {
return false, err
}
v := int(version)
if (v >= vsn_min) && (v <= vsn_max) {
numWhoGrok++
}
}
return (numServers > 0) && (numWhoGrok == numServers), nil
}
// ServerMinRaftProtocol returns the lowest supported Raft protocol among alive servers
func ServerMinRaftProtocol(members []serf.Member) (int, error) {
minVersion := -1
for _, m := range members {
if m.Tags["role"] != "consul" || m.Status != serf.StatusAlive {
continue
}
vsn, ok := m.Tags["raft_vsn"]
if !ok {
vsn = "1"
}
raftVsn, err := strconv.Atoi(vsn)
if err != nil {
return -1, err
}
if minVersion == -1 || raftVsn < minVersion {
minVersion = raftVsn
}
}
if minVersion == -1 {
return minVersion, fmt.Errorf("No servers found")
}
return minVersion, nil
}
// Returns if a member is a consul node. Returns a bool,
// and the datacenter.
func isConsulNode(m serf.Member) (bool, string) {
if m.Tags["role"] != "node" {
return false, ""
}
return true, m.Tags["dc"]
}
// Returns if the given IP is in a private block
func isPrivateIP(ip_str string) bool {
ip := net.ParseIP(ip_str)
for _, priv := range privateBlocks {
if priv.Contains(ip) {
return true
}
}
return false
}
// Returns addresses from interfaces that is up
func activeInterfaceAddresses() ([]net.Addr, error) {
var upAddrs []net.Addr
var loAddrs []net.Addr
interfaces, err := net.Interfaces()
if err != nil {
return nil, fmt.Errorf("Failed to get interfaces: %v", err)
}
for _, iface := range interfaces {
// Require interface to be up
if iface.Flags&net.FlagUp == 0 {
continue
}
addresses, err := iface.Addrs()
if err != nil {
return nil, fmt.Errorf("Failed to get interface addresses: %v", err)
}
if iface.Flags&net.FlagLoopback != 0 {
loAddrs = append(loAddrs, addresses...)
continue
}
upAddrs = append(upAddrs, addresses...)
}
if len(upAddrs) == 0 {
return loAddrs, nil
}
return upAddrs, nil
}
// GetPrivateIP is used to return the first private IP address
// associated with an interface on the machine
func GetPrivateIP() (net.IP, error) {
addresses, err := activeInterfaceAddresses()
if err != nil {
return nil, fmt.Errorf("Failed to get interface addresses: %v", err)
}
return getPrivateIP(addresses)
}
func getPrivateIP(addresses []net.Addr) (net.IP, error) {
var candidates []net.IP
// Find private IPv4 address
for _, rawAddr := range addresses {
var ip net.IP
switch addr := rawAddr.(type) {
case *net.IPAddr:
ip = addr.IP
case *net.IPNet:
ip = addr.IP
default:
continue
}
if ip.To4() == nil {
continue
}
if !isPrivateIP(ip.String()) {
continue
}
candidates = append(candidates, ip)
}
numIps := len(candidates)
switch numIps {
case 0:
return nil, fmt.Errorf("No private IP address found")
case 1:
return candidates[0], nil
default:
return nil, fmt.Errorf("Multiple private IPs found. Please configure one.")
}
}
// GetPublicIPv6 is used to return the first public IP address
// associated with an interface on the machine
func GetPublicIPv6() (net.IP, error) {
addresses, err := net.InterfaceAddrs()
if err != nil {
return nil, fmt.Errorf("Failed to get interface addresses: %v", err)
}
return getPublicIPv6(addresses)
}
func isUniqueLocalAddress(ip net.IP) bool {
return len(ip) == net.IPv6len && ip[0] == 0xfc && ip[1] == 0x00
}
func getPublicIPv6(addresses []net.Addr) (net.IP, error) {
var candidates []net.IP
// Find public IPv6 address
for _, rawAddr := range addresses {
var ip net.IP
switch addr := rawAddr.(type) {
case *net.IPAddr:
ip = addr.IP
case *net.IPNet:
ip = addr.IP
default:
continue
}
if ip.To4() != nil {
continue
}
if ip.IsLinkLocalUnicast() || isUniqueLocalAddress(ip) || ip.IsLoopback() {
continue
}
candidates = append(candidates, ip)
}
numIps := len(candidates)
switch numIps {
case 0:
return nil, fmt.Errorf("No public IPv6 address found")
case 1:
return candidates[0], nil
default:
return nil, fmt.Errorf("Multiple public IPv6 addresses found. Please configure one.")
}
}
// Converts bytes to an integer
func bytesToUint64(b []byte) uint64 {
return binary.BigEndian.Uint64(b)
}
// Converts a uint to a byte slice
func uint64ToBytes(u uint64) []byte {
buf := make([]byte, 8)
binary.BigEndian.PutUint64(buf, u)
return buf
}
// runtimeStats is used to return various runtime information
func runtimeStats() map[string]string {
return map[string]string{
"os": runtime.GOOS,
"arch": runtime.GOARCH,
"version": runtime.Version(),
"max_procs": strconv.FormatInt(int64(runtime.GOMAXPROCS(0)), 10),
"goroutines": strconv.FormatInt(int64(runtime.NumGoroutine()), 10),
"cpu_count": strconv.FormatInt(int64(runtime.NumCPU()), 10),
}
}
// ServersMeetMinimumVersion returns whether the given alive servers are at least on the
// given Consul version
func ServersMeetMinimumVersion(members []serf.Member, minVersion *version.Version) bool {
for _, member := range members {
if valid, parts := metadata.IsConsulServer(member); valid && parts.Status == serf.StatusAlive {
if parts.Build.LessThan(minVersion) {
return false
}
}
}
return true
}