summaryrefslogtreecommitdiffhomepage
path: root/pkg/tcpip
diff options
context:
space:
mode:
Diffstat (limited to 'pkg/tcpip')
-rw-r--r--pkg/tcpip/stack/iptables.go75
-rw-r--r--pkg/tcpip/stack/iptables_targets.go54
-rw-r--r--pkg/tcpip/stack/iptables_types.go41
-rw-r--r--pkg/tcpip/stack/stack.go10
4 files changed, 58 insertions, 122 deletions
diff --git a/pkg/tcpip/stack/iptables.go b/pkg/tcpip/stack/iptables.go
index 8d6d9a7f1..df6bd1315 100644
--- a/pkg/tcpip/stack/iptables.go
+++ b/pkg/tcpip/stack/iptables.go
@@ -22,30 +22,17 @@ import (
"gvisor.dev/gvisor/pkg/tcpip/header"
)
-// tableID is an index into IPTables.tables.
-type tableID int
+// TableID identifies a specific table.
+type TableID int
+// Each value identifies a specfic table.
const (
- natID tableID = iota
- mangleID
- filterID
- numTables
+ NATID TableID = iota
+ MangleID
+ FilterID
+ NumTables
)
-// Table names.
-const (
- NATTable = "nat"
- MangleTable = "mangle"
- FilterTable = "filter"
-)
-
-// nameToID is immutable.
-var nameToID = map[string]tableID{
- NATTable: natID,
- MangleTable: mangleID,
- FilterTable: filterID,
-}
-
// HookUnset indicates that there is no hook set for an entrypoint or
// underflow.
const HookUnset = -1
@@ -57,8 +44,8 @@ const reaperDelay = 5 * time.Second
// all packets.
func DefaultTables() *IPTables {
return &IPTables{
- v4Tables: [numTables]Table{
- natID: Table{
+ v4Tables: [NumTables]Table{
+ NATID: Table{
Rules: []Rule{
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv4ProtocolNumber}},
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv4ProtocolNumber}},
@@ -81,7 +68,7 @@ func DefaultTables() *IPTables {
Postrouting: 3,
},
},
- mangleID: Table{
+ MangleID: Table{
Rules: []Rule{
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv4ProtocolNumber}},
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv4ProtocolNumber}},
@@ -99,7 +86,7 @@ func DefaultTables() *IPTables {
Postrouting: HookUnset,
},
},
- filterID: Table{
+ FilterID: Table{
Rules: []Rule{
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv4ProtocolNumber}},
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv4ProtocolNumber}},
@@ -122,8 +109,8 @@ func DefaultTables() *IPTables {
},
},
},
- v6Tables: [numTables]Table{
- natID: Table{
+ v6Tables: [NumTables]Table{
+ NATID: Table{
Rules: []Rule{
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv6ProtocolNumber}},
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv6ProtocolNumber}},
@@ -146,7 +133,7 @@ func DefaultTables() *IPTables {
Postrouting: 3,
},
},
- mangleID: Table{
+ MangleID: Table{
Rules: []Rule{
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv6ProtocolNumber}},
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv6ProtocolNumber}},
@@ -164,7 +151,7 @@ func DefaultTables() *IPTables {
Postrouting: HookUnset,
},
},
- filterID: Table{
+ FilterID: Table{
Rules: []Rule{
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv6ProtocolNumber}},
Rule{Target: &AcceptTarget{NetworkProtocol: header.IPv6ProtocolNumber}},
@@ -187,10 +174,10 @@ func DefaultTables() *IPTables {
},
},
},
- priorities: [NumHooks][]tableID{
- Prerouting: []tableID{mangleID, natID},
- Input: []tableID{natID, filterID},
- Output: []tableID{mangleID, natID, filterID},
+ priorities: [NumHooks][]TableID{
+ Prerouting: []TableID{MangleID, NATID},
+ Input: []TableID{NATID, FilterID},
+ Output: []TableID{MangleID, NATID, FilterID},
},
connections: ConnTrack{
seed: generateRandUint32(),
@@ -229,26 +216,20 @@ func EmptyNATTable() Table {
}
}
-// GetTable returns a table by name.
-func (it *IPTables) GetTable(name string, ipv6 bool) (Table, bool) {
- id, ok := nameToID[name]
- if !ok {
- return Table{}, false
- }
+// GetTable returns a table with the given id and IP version. It panics when an
+// invalid id is provided.
+func (it *IPTables) GetTable(id TableID, ipv6 bool) Table {
it.mu.RLock()
defer it.mu.RUnlock()
if ipv6 {
- return it.v6Tables[id], true
+ return it.v6Tables[id]
}
- return it.v4Tables[id], true
+ return it.v4Tables[id]
}
-// ReplaceTable replaces or inserts table by name.
-func (it *IPTables) ReplaceTable(name string, table Table, ipv6 bool) *tcpip.Error {
- id, ok := nameToID[name]
- if !ok {
- return tcpip.ErrInvalidOptionValue
- }
+// ReplaceTable replaces or inserts table by name. It panics when an invalid id
+// is provided.
+func (it *IPTables) ReplaceTable(id TableID, table Table, ipv6 bool) *tcpip.Error {
it.mu.Lock()
defer it.mu.Unlock()
// If iptables is being enabled, initialize the conntrack table and
@@ -311,7 +292,7 @@ func (it *IPTables) Check(hook Hook, pkt *PacketBuffer, gso *GSO, r *Route, prer
for _, tableID := range priorities {
// If handlePacket already NATed the packet, we don't need to
// check the NAT table.
- if tableID == natID && pkt.NatDone {
+ if tableID == NATID && pkt.NatDone {
continue
}
var table Table
diff --git a/pkg/tcpip/stack/iptables_targets.go b/pkg/tcpip/stack/iptables_targets.go
index 538c4625d..94a5df329 100644
--- a/pkg/tcpip/stack/iptables_targets.go
+++ b/pkg/tcpip/stack/iptables_targets.go
@@ -26,13 +26,6 @@ type AcceptTarget struct {
NetworkProtocol tcpip.NetworkProtocolNumber
}
-// ID implements Target.ID.
-func (at *AcceptTarget) ID() TargetID {
- return TargetID{
- NetworkProtocol: at.NetworkProtocol,
- }
-}
-
// Action implements Target.Action.
func (*AcceptTarget) Action(*PacketBuffer, *ConnTrack, Hook, *GSO, *Route, tcpip.Address) (RuleVerdict, int) {
return RuleAccept, 0
@@ -44,22 +37,11 @@ type DropTarget struct {
NetworkProtocol tcpip.NetworkProtocolNumber
}
-// ID implements Target.ID.
-func (dt *DropTarget) ID() TargetID {
- return TargetID{
- NetworkProtocol: dt.NetworkProtocol,
- }
-}
-
// Action implements Target.Action.
func (*DropTarget) Action(*PacketBuffer, *ConnTrack, Hook, *GSO, *Route, tcpip.Address) (RuleVerdict, int) {
return RuleDrop, 0
}
-// ErrorTargetName is used to mark targets as error targets. Error targets
-// shouldn't be reached - an error has occurred if we fall through to one.
-const ErrorTargetName = "ERROR"
-
// ErrorTarget logs an error and drops the packet. It represents a target that
// should be unreachable.
type ErrorTarget struct {
@@ -67,14 +49,6 @@ type ErrorTarget struct {
NetworkProtocol tcpip.NetworkProtocolNumber
}
-// ID implements Target.ID.
-func (et *ErrorTarget) ID() TargetID {
- return TargetID{
- Name: ErrorTargetName,
- NetworkProtocol: et.NetworkProtocol,
- }
-}
-
// Action implements Target.Action.
func (*ErrorTarget) Action(*PacketBuffer, *ConnTrack, Hook, *GSO, *Route, tcpip.Address) (RuleVerdict, int) {
log.Debugf("ErrorTarget triggered.")
@@ -90,14 +64,6 @@ type UserChainTarget struct {
NetworkProtocol tcpip.NetworkProtocolNumber
}
-// ID implements Target.ID.
-func (uc *UserChainTarget) ID() TargetID {
- return TargetID{
- Name: ErrorTargetName,
- NetworkProtocol: uc.NetworkProtocol,
- }
-}
-
// Action implements Target.Action.
func (*UserChainTarget) Action(*PacketBuffer, *ConnTrack, Hook, *GSO, *Route, tcpip.Address) (RuleVerdict, int) {
panic("UserChainTarget should never be called.")
@@ -110,23 +76,11 @@ type ReturnTarget struct {
NetworkProtocol tcpip.NetworkProtocolNumber
}
-// ID implements Target.ID.
-func (rt *ReturnTarget) ID() TargetID {
- return TargetID{
- NetworkProtocol: rt.NetworkProtocol,
- }
-}
-
// Action implements Target.Action.
func (*ReturnTarget) Action(*PacketBuffer, *ConnTrack, Hook, *GSO, *Route, tcpip.Address) (RuleVerdict, int) {
return RuleReturn, 0
}
-// RedirectTargetName is used to mark targets as redirect targets. Redirect
-// targets should be reached for only NAT and Mangle tables. These targets will
-// change the destination port/destination IP for packets.
-const RedirectTargetName = "REDIRECT"
-
// RedirectTarget redirects the packet by modifying the destination port/IP.
// TODO(gvisor.dev/issue/170): Other flags need to be added after we support
// them.
@@ -141,14 +95,6 @@ type RedirectTarget struct {
NetworkProtocol tcpip.NetworkProtocolNumber
}
-// ID implements Target.ID.
-func (rt *RedirectTarget) ID() TargetID {
- return TargetID{
- Name: RedirectTargetName,
- NetworkProtocol: rt.NetworkProtocol,
- }
-}
-
// Action implements Target.Action.
// TODO(gvisor.dev/issue/170): Parse headers without copying. The current
// implementation only works for PREROUTING and calls pkt.Clone(), neither
diff --git a/pkg/tcpip/stack/iptables_types.go b/pkg/tcpip/stack/iptables_types.go
index 7b3f3e88b..4b86c1be9 100644
--- a/pkg/tcpip/stack/iptables_types.go
+++ b/pkg/tcpip/stack/iptables_types.go
@@ -37,7 +37,6 @@ import (
// ----->[Prerouting]----->routing----->[Forward]---------[Postrouting]----->
type Hook uint
-// These values correspond to values in include/uapi/linux/netfilter.h.
const (
// Prerouting happens before a packet is routed to applications or to
// be forwarded.
@@ -86,8 +85,8 @@ type IPTables struct {
mu sync.RWMutex
// v4Tables and v6tables map tableIDs to tables. They hold builtin
// tables only, not user tables. mu must be locked for accessing.
- v4Tables [numTables]Table
- v6Tables [numTables]Table
+ v4Tables [NumTables]Table
+ v6Tables [NumTables]Table
// modified is whether tables have been modified at least once. It is
// used to elide the iptables performance overhead for workloads that
// don't utilize iptables.
@@ -96,7 +95,7 @@ type IPTables struct {
// priorities maps each hook to a list of table names. The order of the
// list is the order in which each table should be visited for that
// hook. It is immutable.
- priorities [NumHooks][]tableID
+ priorities [NumHooks][]TableID
connections ConnTrack
@@ -104,6 +103,24 @@ type IPTables struct {
reaperDone chan struct{}
}
+// VisitTargets traverses all the targets of all tables and replaces each with
+// transform(target).
+func (it *IPTables) VisitTargets(transform func(Target) Target) {
+ it.mu.Lock()
+ defer it.mu.Unlock()
+
+ for tid := range it.v4Tables {
+ for i, rule := range it.v4Tables[tid].Rules {
+ it.v4Tables[tid].Rules[i].Target = transform(rule.Target)
+ }
+ }
+ for tid := range it.v6Tables {
+ for i, rule := range it.v6Tables[tid].Rules {
+ it.v6Tables[tid].Rules[i].Target = transform(rule.Target)
+ }
+ }
+}
+
// A Table defines a set of chains and hooks into the network stack.
//
// It is a list of Rules, entry points (BuiltinChains), and error handlers
@@ -169,7 +186,6 @@ type IPHeaderFilter struct {
// CheckProtocol determines whether the Protocol field should be
// checked during matching.
- // TODO(gvisor.dev/issue/3549): Check this field during matching.
CheckProtocol bool
// Dst matches the destination IP address.
@@ -309,23 +325,8 @@ type Matcher interface {
Match(hook Hook, packet *PacketBuffer, interfaceName string) (matches bool, hotdrop bool)
}
-// A TargetID uniquely identifies a target.
-type TargetID struct {
- // Name is the target name as stored in the xt_entry_target struct.
- Name string
-
- // NetworkProtocol is the protocol to which the target applies.
- NetworkProtocol tcpip.NetworkProtocolNumber
-
- // Revision is the version of the target.
- Revision uint8
-}
-
// A Target is the interface for taking an action for a packet.
type Target interface {
- // ID uniquely identifies the Target.
- ID() TargetID
-
// Action takes an action on the packet and returns a verdict on how
// traversal should (or should not) continue. If the return value is
// Jump, it also returns the index of the rule to jump to.
diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go
index e8f1c110e..25ea6b459 100644
--- a/pkg/tcpip/stack/stack.go
+++ b/pkg/tcpip/stack/stack.go
@@ -518,6 +518,10 @@ type Options struct {
//
// RandSource must be thread-safe.
RandSource mathrand.Source
+
+ // IPTables are the initial iptables rules. If nil, iptables will allow
+ // all traffic.
+ IPTables *IPTables
}
// TransportEndpointInfo holds useful information about a transport endpoint
@@ -620,6 +624,10 @@ func New(opts Options) *Stack {
randSrc = &lockedRandomSource{src: mathrand.NewSource(generateRandInt64())}
}
+ if opts.IPTables == nil {
+ opts.IPTables = DefaultTables()
+ }
+
opts.NUDConfigs.resetInvalidFields()
s := &Stack{
@@ -633,7 +641,7 @@ func New(opts Options) *Stack {
clock: clock,
stats: opts.Stats.FillIn(),
handleLocal: opts.HandleLocal,
- tables: DefaultTables(),
+ tables: opts.IPTables,
icmpRateLimiter: NewICMPRateLimiter(),
seed: generateRandUint32(),
nudConfigs: opts.NUDConfigs,
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 12:46:13 +0000