checkpoint.go

Documentation: k8s.io/kubernetes/pkg/kubelet/cm/dra/state

     1  /*
     2  Copyright 2023 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package state
    18  
    19  import (
    20  	"encoding/json"
    21  	"fmt"
    22  	"hash/fnv"
    23  	"strings"
    24  
    25  	"k8s.io/apimachinery/pkg/util/dump"
    26  	"k8s.io/kubernetes/pkg/kubelet/checkpointmanager"
    27  	"k8s.io/kubernetes/pkg/kubelet/checkpointmanager/checksum"
    28  	"k8s.io/kubernetes/pkg/kubelet/checkpointmanager/errors"
    29  )
    30  
    31  var _ checkpointmanager.Checkpoint = &DRAManagerCheckpoint{}
    32  
    33  const checkpointVersion = "v1"
    34  
    35  // DRAManagerCheckpoint struct is used to store pod dynamic resources assignments in a checkpoint
    36  type DRAManagerCheckpoint struct {
    37  	Version  string             `json:"version"`
    38  	Entries  ClaimInfoStateList `json:"entries,omitempty"`
    39  	Checksum checksum.Checksum  `json:"checksum"`
    40  }
    41  
    42  // DraManagerCheckpoint struct is an old implementation of the DraManagerCheckpoint
    43  type DRAManagerCheckpointWithoutResourceHandles struct {
    44  	Version  string                                   `json:"version"`
    45  	Entries  ClaimInfoStateListWithoutResourceHandles `json:"entries,omitempty"`
    46  	Checksum checksum.Checksum                        `json:"checksum"`
    47  }
    48  
    49  // List of claim info to store in checkpoint
    50  type ClaimInfoStateList []ClaimInfoState
    51  
    52  // List of claim info to store in checkpoint
    53  // TODO: remove in Beta
    54  type ClaimInfoStateListWithoutResourceHandles []ClaimInfoStateWithoutResourceHandles
    55  
    56  // NewDRAManagerCheckpoint returns an instance of Checkpoint
    57  func NewDRAManagerCheckpoint() *DRAManagerCheckpoint {
    58  	return &DRAManagerCheckpoint{
    59  		Version: checkpointVersion,
    60  		Entries: ClaimInfoStateList{},
    61  	}
    62  }
    63  
    64  // MarshalCheckpoint returns marshalled checkpoint
    65  func (dc *DRAManagerCheckpoint) MarshalCheckpoint() ([]byte, error) {
    66  	// make sure checksum wasn't set before so it doesn't affect output checksum
    67  	dc.Checksum = 0
    68  	dc.Checksum = checksum.New(dc)
    69  	return json.Marshal(*dc)
    70  }
    71  
    72  // UnmarshalCheckpoint tries to unmarshal passed bytes to checkpoint
    73  func (dc *DRAManagerCheckpoint) UnmarshalCheckpoint(blob []byte) error {
    74  	return json.Unmarshal(blob, dc)
    75  }
    76  
    77  // VerifyChecksum verifies that current checksum of checkpoint is valid
    78  func (dc *DRAManagerCheckpoint) VerifyChecksum() error {
    79  	ck := dc.Checksum
    80  	dc.Checksum = 0
    81  	err := ck.Verify(dc)
    82  	if err == errors.ErrCorruptCheckpoint {
    83  		// Verify with old structs without ResourceHandles field
    84  		// TODO: remove in Beta
    85  		err = verifyChecksumWithoutResourceHandles(dc, ck)
    86  	}
    87  	dc.Checksum = ck
    88  	return err
    89  }
    90  
    91  // verifyChecksumWithoutResourceHandles is a helper function that verifies checksum of the
    92  // checkpoint in the old format, without ResourceHandles field.
    93  // TODO: remove in Beta.
    94  func verifyChecksumWithoutResourceHandles(dc *DRAManagerCheckpoint, checkSum checksum.Checksum) error {
    95  	entries := ClaimInfoStateListWithoutResourceHandles{}
    96  	for _, entry := range dc.Entries {
    97  		entries = append(entries, ClaimInfoStateWithoutResourceHandles{
    98  			DriverName: entry.DriverName,
    99  			ClassName:  entry.ClassName,
   100  			ClaimUID:   entry.ClaimUID,
   101  			ClaimName:  entry.ClaimName,
   102  			Namespace:  entry.Namespace,
   103  			PodUIDs:    entry.PodUIDs,
   104  			CDIDevices: entry.CDIDevices,
   105  		})
   106  	}
   107  	oldcheckpoint := &DRAManagerCheckpointWithoutResourceHandles{
   108  		Version:  checkpointVersion,
   109  		Entries:  entries,
   110  		Checksum: 0,
   111  	}
   112  	// Calculate checksum for old checkpoint
   113  	object := dump.ForHash(oldcheckpoint)
   114  	object = strings.Replace(object, "DRAManagerCheckpointWithoutResourceHandles", "DRAManagerCheckpoint", 1)
   115  	object = strings.Replace(object, "ClaimInfoStateListWithoutResourceHandles", "ClaimInfoStateList", 1)
   116  	hash := fnv.New32a()
   117  	fmt.Fprintf(hash, "%v", object)
   118  	if checkSum != checksum.Checksum(hash.Sum32()) {
   119  		return errors.ErrCorruptCheckpoint
   120  	}
   121  	return nil
   122  }
   123
View as plain text