[management, client] Add access control support to network routes (#2100)

This commit is contained in:
Bethuel Mmbaga
2024-10-02 14:41:00 +03:00
committed by GitHub
parent a3a479429e
commit ff7863785f
48 changed files with 4683 additions and 2444 deletions

View File

@ -19,24 +19,22 @@ const (
// rules chains contains the effective ACL rules
chainNameInputRules = "NETBIRD-ACL-INPUT"
chainNameOutputRules = "NETBIRD-ACL-OUTPUT"
postRoutingMark = "0x000007e4"
)
type aclManager struct {
iptablesClient *iptables.IPTables
wgIface iFaceMapper
routeingFwChainName string
iptablesClient *iptables.IPTables
wgIface iFaceMapper
routingFwChainName string
entries map[string][][]string
ipsetStore *ipsetStore
}
func newAclManager(iptablesClient *iptables.IPTables, wgIface iFaceMapper, routeingFwChainName string) (*aclManager, error) {
func newAclManager(iptablesClient *iptables.IPTables, wgIface iFaceMapper, routingFwChainName string) (*aclManager, error) {
m := &aclManager{
iptablesClient: iptablesClient,
wgIface: wgIface,
routeingFwChainName: routeingFwChainName,
iptablesClient: iptablesClient,
wgIface: wgIface,
routingFwChainName: routingFwChainName,
entries: make(map[string][][]string),
ipsetStore: newIpsetStore(),
@ -61,7 +59,7 @@ func newAclManager(iptablesClient *iptables.IPTables, wgIface iFaceMapper, route
return m, nil
}
func (m *aclManager) AddFiltering(
func (m *aclManager) AddPeerFiltering(
ip net.IP,
protocol firewall.Protocol,
sPort *firewall.Port,
@ -127,7 +125,7 @@ func (m *aclManager) AddFiltering(
return nil, fmt.Errorf("rule already exists")
}
if err := m.iptablesClient.Insert("filter", chain, 1, specs...); err != nil {
if err := m.iptablesClient.Append("filter", chain, specs...); err != nil {
return nil, err
}
@ -139,28 +137,16 @@ func (m *aclManager) AddFiltering(
chain: chain,
}
if !shouldAddToPrerouting(protocol, dPort, direction) {
return []firewall.Rule{rule}, nil
}
rulePrerouting, err := m.addPreroutingFilter(ipsetName, string(protocol), dPortVal, ip)
if err != nil {
return []firewall.Rule{rule}, err
}
return []firewall.Rule{rule, rulePrerouting}, nil
return []firewall.Rule{rule}, nil
}
// DeleteRule from the firewall by rule definition
func (m *aclManager) DeleteRule(rule firewall.Rule) error {
// DeletePeerRule from the firewall by rule definition
func (m *aclManager) DeletePeerRule(rule firewall.Rule) error {
r, ok := rule.(*Rule)
if !ok {
return fmt.Errorf("invalid rule type")
}
if r.chain == "PREROUTING" {
goto DELETERULE
}
if ipsetList, ok := m.ipsetStore.ipset(r.ipsetName); ok {
// delete IP from ruleset IPs list and ipset
if _, ok := ipsetList.ips[r.ip]; ok {
@ -185,14 +171,7 @@ func (m *aclManager) DeleteRule(rule firewall.Rule) error {
}
}
DELETERULE:
var table string
if r.chain == "PREROUTING" {
table = "mangle"
} else {
table = "filter"
}
err := m.iptablesClient.Delete(table, r.chain, r.specs...)
err := m.iptablesClient.Delete(tableName, r.chain, r.specs...)
if err != nil {
log.Debugf("failed to delete rule, %s, %v: %s", r.chain, r.specs, err)
}
@ -203,44 +182,6 @@ func (m *aclManager) Reset() error {
return m.cleanChains()
}
func (m *aclManager) addPreroutingFilter(ipsetName string, protocol string, port string, ip net.IP) (*Rule, error) {
var src []string
if ipsetName != "" {
src = []string{"-m", "set", "--set", ipsetName, "src"}
} else {
src = []string{"-s", ip.String()}
}
specs := []string{
"-d", m.wgIface.Address().IP.String(),
"-p", protocol,
"--dport", port,
"-j", "MARK", "--set-mark", postRoutingMark,
}
specs = append(src, specs...)
ok, err := m.iptablesClient.Exists("mangle", "PREROUTING", specs...)
if err != nil {
return nil, fmt.Errorf("failed to check rule: %w", err)
}
if ok {
return nil, fmt.Errorf("rule already exists")
}
if err := m.iptablesClient.Insert("mangle", "PREROUTING", 1, specs...); err != nil {
return nil, err
}
rule := &Rule{
ruleID: uuid.New().String(),
specs: specs,
ipsetName: ipsetName,
ip: ip.String(),
chain: "PREROUTING",
}
return rule, nil
}
// todo write less destructive cleanup mechanism
func (m *aclManager) cleanChains() error {
ok, err := m.iptablesClient.ChainExists(tableName, chainNameOutputRules)
@ -291,25 +232,6 @@ func (m *aclManager) cleanChains() error {
}
}
ok, err = m.iptablesClient.ChainExists("mangle", "PREROUTING")
if err != nil {
log.Debugf("failed to list chains: %s", err)
return err
}
if ok {
for _, rule := range m.entries["PREROUTING"] {
err := m.iptablesClient.DeleteIfExists("mangle", "PREROUTING", rule...)
if err != nil {
log.Errorf("failed to delete rule: %v, %s", rule, err)
}
}
err = m.iptablesClient.ClearChain("mangle", "PREROUTING")
if err != nil {
log.Debugf("failed to clear %s chain: %s", "PREROUTING", err)
return err
}
}
for _, ipsetName := range m.ipsetStore.ipsetNames() {
if err := ipset.Flush(ipsetName); err != nil {
log.Errorf("flush ipset %q during reset: %v", ipsetName, err)
@ -338,17 +260,9 @@ func (m *aclManager) createDefaultChains() error {
for chainName, rules := range m.entries {
for _, rule := range rules {
if chainName == "FORWARD" {
// position 2 because we add it after router's, jump rule
if err := m.iptablesClient.InsertUnique(tableName, "FORWARD", 2, rule...); err != nil {
log.Debugf("failed to create input chain jump rule: %s", err)
return err
}
} else {
if err := m.iptablesClient.AppendUnique(tableName, chainName, rule...); err != nil {
log.Debugf("failed to create input chain jump rule: %s", err)
return err
}
if err := m.iptablesClient.InsertUnique(tableName, chainName, 1, rule...); err != nil {
log.Debugf("failed to create input chain jump rule: %s", err)
return err
}
}
}
@ -356,40 +270,29 @@ func (m *aclManager) createDefaultChains() error {
return nil
}
// seedInitialEntries adds default rules to the entries map, rules are inserted on pos 1, hence the order is reversed.
// We want to make sure our traffic is not dropped by existing rules.
// The existing FORWARD rules/policies decide outbound traffic towards our interface.
// In case the FORWARD policy is set to "drop", we add an established/related rule to allow return traffic for the inbound rule.
// The OUTPUT chain gets an extra rule to allow traffic to any set up routes, the return traffic is handled by the INPUT related/established rule.
func (m *aclManager) seedInitialEntries() {
m.appendToEntries("INPUT",
[]string{"-i", m.wgIface.Name(), "!", "-s", m.wgIface.Address().String(), "-d", m.wgIface.Address().String(), "-j", "ACCEPT"})
m.appendToEntries("INPUT",
[]string{"-i", m.wgIface.Name(), "-s", m.wgIface.Address().String(), "!", "-d", m.wgIface.Address().String(), "-j", "ACCEPT"})
m.appendToEntries("INPUT",
[]string{"-i", m.wgIface.Name(), "-s", m.wgIface.Address().String(), "-d", m.wgIface.Address().String(), "-j", chainNameInputRules})
established := getConntrackEstablished()
m.appendToEntries("INPUT", []string{"-i", m.wgIface.Name(), "-j", "DROP"})
m.appendToEntries("OUTPUT",
[]string{"-o", m.wgIface.Name(), "!", "-s", m.wgIface.Address().String(), "-d", m.wgIface.Address().String(), "-j", "ACCEPT"})
m.appendToEntries("OUTPUT",
[]string{"-o", m.wgIface.Name(), "-s", m.wgIface.Address().String(), "!", "-d", m.wgIface.Address().String(), "-j", "ACCEPT"})
m.appendToEntries("OUTPUT",
[]string{"-o", m.wgIface.Name(), "-s", m.wgIface.Address().String(), "-d", m.wgIface.Address().String(), "-j", chainNameOutputRules})
m.appendToEntries("INPUT", []string{"-i", m.wgIface.Name(), "-j", chainNameInputRules})
m.appendToEntries("INPUT", append([]string{"-i", m.wgIface.Name()}, established...))
m.appendToEntries("OUTPUT", []string{"-o", m.wgIface.Name(), "-j", "DROP"})
m.appendToEntries("OUTPUT", []string{"-o", m.wgIface.Name(), "-j", chainNameOutputRules})
m.appendToEntries("OUTPUT", []string{"-o", m.wgIface.Name(), "!", "-d", m.wgIface.Address().String(), "-j", "ACCEPT"})
m.appendToEntries("OUTPUT", append([]string{"-o", m.wgIface.Name()}, established...))
m.appendToEntries("FORWARD", []string{"-i", m.wgIface.Name(), "-j", "DROP"})
m.appendToEntries("FORWARD", []string{"-i", m.wgIface.Name(), "-j", chainNameInputRules})
m.appendToEntries("FORWARD",
[]string{"-o", m.wgIface.Name(), "-m", "mark", "--mark", postRoutingMark, "-j", "ACCEPT"})
m.appendToEntries("FORWARD",
[]string{"-i", m.wgIface.Name(), "-m", "mark", "--mark", postRoutingMark, "-j", "ACCEPT"})
m.appendToEntries("FORWARD", []string{"-o", m.wgIface.Name(), "-j", m.routeingFwChainName})
m.appendToEntries("FORWARD", []string{"-i", m.wgIface.Name(), "-j", m.routeingFwChainName})
m.appendToEntries("PREROUTING",
[]string{"-t", "mangle", "-i", m.wgIface.Name(), "!", "-s", m.wgIface.Address().String(), "-d", m.wgIface.Address().IP.String(), "-m", "mark", "--mark", postRoutingMark})
m.appendToEntries("FORWARD", []string{"-i", m.wgIface.Name(), "-j", m.routingFwChainName})
m.appendToEntries("FORWARD", append([]string{"-o", m.wgIface.Name()}, established...))
}
func (m *aclManager) appendToEntries(chainName string, spec []string) {
@ -456,18 +359,3 @@ func transformIPsetName(ipsetName string, sPort, dPort string) string {
return ipsetName
}
}
func shouldAddToPrerouting(proto firewall.Protocol, dPort *firewall.Port, direction firewall.RuleDirection) bool {
if proto == "all" {
return false
}
if direction != firewall.RuleDirectionIN {
return false
}
if dPort == nil {
return false
}
return true
}