diff options
Diffstat (limited to 'pkg/tcpip/tcpip.go')
| -rw-r--r-- | pkg/tcpip/tcpip.go | 160 |
1 files changed, 122 insertions, 38 deletions
diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go index 043dd549b..a35d6562e 100644 --- a/pkg/tcpip/tcpip.go +++ b/pkg/tcpip/tcpip.go @@ -57,6 +57,9 @@ type Error struct { // String implements fmt.Stringer.String. func (e *Error) String() string { + if e == nil { + return "<nil>" + } return e.msg } @@ -219,6 +222,15 @@ func (s *Subnet) Mask() AddressMask { return s.mask } +// Broadcast returns the subnet's broadcast address. +func (s *Subnet) Broadcast() Address { + addr := []byte(s.address) + for i := range addr { + addr[i] |= ^s.mask[i] + } + return Address(addr) +} + // NICID is a number that uniquely identifies a NIC. type NICID int32 @@ -252,31 +264,34 @@ type FullAddress struct { Port uint16 } -// Payload provides an interface around data that is being sent to an endpoint. -// This allows the endpoint to request the amount of data it needs based on -// internal buffers without exposing them. 'p.Get(p.Size())' reads all the data. -type Payload interface { - // Get returns a slice containing exactly 'min(size, p.Size())' bytes. - Get(size int) ([]byte, *Error) - - // Size returns the payload size. - Size() int +// Payloader is an interface that provides data. +// +// This interface allows the endpoint to request the amount of data it needs +// based on internal buffers without exposing them. +type Payloader interface { + // FullPayload returns all available bytes. + FullPayload() ([]byte, *Error) + + // Payload returns a slice containing at most size bytes. + Payload(size int) ([]byte, *Error) } -// SlicePayload implements Payload on top of slices for convenience. +// SlicePayload implements Payloader for slices. +// +// This is typically used for tests. type SlicePayload []byte -// Get implements Payload. -func (s SlicePayload) Get(size int) ([]byte, *Error) { - if size > s.Size() { - size = s.Size() - } - return s[:size], nil +// FullPayload implements Payloader.FullPayload. +func (s SlicePayload) FullPayload() ([]byte, *Error) { + return s, nil } -// Size implements Payload. -func (s SlicePayload) Size() int { - return len(s) +// Payload implements Payloader.Payload. +func (s SlicePayload) Payload(size int) ([]byte, *Error) { + if size > len(s) { + size = len(s) + } + return s[:size], nil } // A ControlMessages contains socket control messages for IP sockets. @@ -329,7 +344,7 @@ type Endpoint interface { // ErrNoLinkAddress and a notification channel is returned for the caller to // block. Channel is closed once address resolution is complete (success or // not). The channel is only non-nil in this case. - Write(Payload, WriteOptions) (int64, <-chan struct{}, *Error) + Write(Payloader, WriteOptions) (int64, <-chan struct{}, *Error) // Peek reads data without consuming it from the endpoint. // @@ -389,6 +404,10 @@ type Endpoint interface { // SetSockOpt sets a socket option. opt should be one of the *Option types. SetSockOpt(opt interface{}) *Error + // SetSockOptInt sets a socket option, for simple cases where a value + // has the int type. + SetSockOptInt(opt SockOpt, v int) *Error + // GetSockOpt gets a socket option. opt should be a pointer to one of the // *Option types. GetSockOpt(opt interface{}) *Error @@ -423,16 +442,33 @@ type WriteOptions struct { // EndOfRecord has the same semantics as Linux's MSG_EOR. EndOfRecord bool + + // Atomic means that all data fetched from Payloader must be written to the + // endpoint. If Atomic is false, then data fetched from the Payloader may be + // discarded if available endpoint buffer space is unsufficient. + Atomic bool } // SockOpt represents socket options which values have the int type. type SockOpt int const ( - // ReceiveQueueSizeOption is used in GetSockOpt to specify that the number of - // unread bytes in the input buffer should be returned. + // ReceiveQueueSizeOption is used in GetSockOptInt to specify that the + // number of unread bytes in the input buffer should be returned. ReceiveQueueSizeOption SockOpt = iota + // SendBufferSizeOption is used by SetSockOptInt/GetSockOptInt to + // specify the send buffer size option. + SendBufferSizeOption + + // ReceiveBufferSizeOption is used by SetSockOptInt/GetSockOptInt to + // specify the receive buffer size option. + ReceiveBufferSizeOption + + // SendQueueSizeOption is used in GetSockOptInt to specify that the + // number of unread bytes in the output buffer should be returned. + SendQueueSizeOption + // TODO(b/137664753): convert all int socket options to be handled via // GetSockOptInt. ) @@ -441,18 +477,6 @@ const ( // the endpoint should be cleared and returned. type ErrorOption struct{} -// SendBufferSizeOption is used by SetSockOpt/GetSockOpt to specify the send -// buffer size option. -type SendBufferSizeOption int - -// ReceiveBufferSizeOption is used by SetSockOpt/GetSockOpt to specify the -// receive buffer size option. -type ReceiveBufferSizeOption int - -// SendQueueSizeOption is used in GetSockOpt to specify that the number of -// unread bytes in the output buffer should be returned. -type SendQueueSizeOption int - // V6OnlyOption is used by SetSockOpt/GetSockOpt to specify whether an IPv6 // socket is to be restricted to sending and receiving IPv6 packets only. type V6OnlyOption int @@ -474,6 +498,10 @@ type ReuseAddressOption int // to be bound to an identical socket address. type ReusePortOption int +// BindToDeviceOption is used by SetSockOpt/GetSockOpt to specify that sockets +// should bind only on a specific NIC. +type BindToDeviceOption string + // QuickAckOption is stubbed out in SetSockOpt/GetSockOpt. type QuickAckOption int @@ -525,6 +553,12 @@ type ModerateReceiveBufferOption bool // Maximum Segment Size(MSS) value as specified using the TCP_MAXSEG option. type MaxSegOption int +// TTLOption is used by SetSockOpt/GetSockOpt to control the default TTL/hop +// limit value for unicast messages. The default is protocol specific. +// +// A zero value indicates the default. +type TTLOption uint8 + // MulticastTTLOption is used by SetSockOpt/GetSockOpt to control the default // TTL value for multicast messages. The default is 1. type MulticastTTLOption uint8 @@ -566,6 +600,10 @@ type OutOfBandInlineOption int // datagram sockets are allowed to send packets to a broadcast address. type BroadcastOption int +// DefaultTTLOption is used by stack.(*Stack).NetworkProtocolOption to specify +// a default TTL. +type DefaultTTLOption uint8 + // Route is a row in the routing table. It specifies through which NIC (and // gateway) sets of packets should be routed. A row is considered viable if the // masked target address matches the destination address in the row. @@ -581,7 +619,7 @@ type Route struct { } // String implements the fmt.Stringer interface. -func (r *Route) String() string { +func (r Route) String() string { var out strings.Builder fmt.Fprintf(&out, "%s", r.Destination) if len(r.Gateway) > 0 { @@ -591,9 +629,6 @@ func (r *Route) String() string { return out.String() } -// LinkEndpointID represents a data link layer endpoint. -type LinkEndpointID uint64 - // TransportProtocolNumber is the number of a transport protocol. type TransportProtocolNumber uint32 @@ -720,6 +755,10 @@ type ICMPv4SentPacketStats struct { // Dropped is the total number of ICMPv4 packets dropped due to link // layer errors. Dropped *StatCounter + + // RateLimited is the total number of ICMPv6 packets dropped due to + // rate limit being exceeded. + RateLimited *StatCounter } // ICMPv4ReceivedPacketStats collects inbound ICMPv4-specific stats. @@ -738,6 +777,10 @@ type ICMPv6SentPacketStats struct { // Dropped is the total number of ICMPv6 packets dropped due to link // layer errors. Dropped *StatCounter + + // RateLimited is the total number of ICMPv6 packets dropped due to + // rate limit being exceeded. + RateLimited *StatCounter } // ICMPv6ReceivedPacketStats collects inbound ICMPv6-specific stats. @@ -1065,6 +1108,47 @@ func (a AddressWithPrefix) String() string { return fmt.Sprintf("%s/%d", a.Address, a.PrefixLen) } +// Subnet converts the address and prefix into a Subnet value and returns it. +func (a AddressWithPrefix) Subnet() Subnet { + addrLen := len(a.Address) + if a.PrefixLen <= 0 { + return Subnet{ + address: Address(strings.Repeat("\x00", addrLen)), + mask: AddressMask(strings.Repeat("\x00", addrLen)), + } + } + if a.PrefixLen >= addrLen*8 { + return Subnet{ + address: a.Address, + mask: AddressMask(strings.Repeat("\xff", addrLen)), + } + } + + sa := make([]byte, addrLen) + sm := make([]byte, addrLen) + n := uint(a.PrefixLen) + for i := 0; i < addrLen; i++ { + if n >= 8 { + sa[i] = a.Address[i] + sm[i] = 0xff + n -= 8 + continue + } + sm[i] = ^byte(0xff >> n) + sa[i] = a.Address[i] & sm[i] + n = 0 + } + + // For extra caution, call NewSubnet rather than directly creating the Subnet + // value. If that fails it indicates a serious bug in this code, so panic is + // in order. + s, err := NewSubnet(Address(sa), AddressMask(sm)) + if err != nil { + panic("invalid subnet: " + err.Error()) + } + return s +} + // ProtocolAddress is an address and the network protocol it is associated // with. type ProtocolAddress struct { |