github.com/imran-kn/cilium-fork@v1.6.9/pkg/bpf/endpoint.go (about)

     1  // Copyright 2016-2019 Authors of Cilium
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package bpf
    16  
    17  import (
    18  	"fmt"
    19  	"net"
    20  	"unsafe"
    21  
    22  	"github.com/cilium/cilium/common/types"
    23  )
    24  
    25  // Must be in sync with ENDPOINT_KEY_* in <bpf/lib/common.h>
    26  const (
    27  	EndpointKeyIPv4 uint8 = 1
    28  	EndpointKeyIPv6 uint8 = 2
    29  )
    30  
    31  // EndpointKey represents the key value of the endpoints BPF map
    32  //
    33  // Must be in sync with struct endpoint_key in <bpf/lib/common.h>
    34  // +k8s:deepcopy-gen=true
    35  type EndpointKey struct {
    36  	// represents both IPv6 and IPv4 (in the lowest four bytes)
    37  	IP     types.IPv6 `align:"$union0"`
    38  	Family uint8      `align:"family"`
    39  	Key    uint8      `align:"key"`
    40  	Pad2   uint16     `align:"pad5"`
    41  }
    42  
    43  // GetKeyPtr returns the unsafe pointer to the BPF key
    44  func (k *EndpointKey) GetKeyPtr() unsafe.Pointer { return unsafe.Pointer(k) }
    45  
    46  // GetValuePtr returns the unsafe pointer to the BPF key for users that
    47  // use EndpointKey as a value in bpf maps
    48  func (k *EndpointKey) GetValuePtr() unsafe.Pointer { return unsafe.Pointer(k) }
    49  
    50  // NewEndpointKey returns an EndpointKey based on the provided IP address. The
    51  // address family is automatically detected.
    52  func NewEndpointKey(ip net.IP) EndpointKey {
    53  	result := EndpointKey{}
    54  
    55  	if ip4 := ip.To4(); ip4 != nil {
    56  		result.Family = EndpointKeyIPv4
    57  		copy(result.IP[:], ip4)
    58  	} else {
    59  		result.Family = EndpointKeyIPv6
    60  		copy(result.IP[:], ip)
    61  	}
    62  	result.Key = 0
    63  
    64  	return result
    65  }
    66  
    67  // ToIP converts the EndpointKey into a net.IP structure.
    68  func (k EndpointKey) ToIP() net.IP {
    69  	switch k.Family {
    70  	case EndpointKeyIPv4:
    71  		return k.IP[:4]
    72  	case EndpointKeyIPv6:
    73  		return k.IP[:]
    74  	}
    75  	return nil
    76  }
    77  
    78  // String provides a string representation of the EndpointKey.
    79  func (k EndpointKey) String() string {
    80  	if ip := k.ToIP(); ip != nil {
    81  		return fmt.Sprintf("%s:%d", ip.String(), k.Key)
    82  	}
    83  	return "nil"
    84  }