lib/cloud/ec2/ec2.go

   1 // Copyright (C) The Arvados Authors. All rights reserved.
   2 //
   3 // SPDX-License-Identifier: AGPL-3.0
   4
   5 package ec2
   6
   7 import (
   8         "crypto/md5"
   9         "crypto/rsa"
  10         "crypto/sha1"
  11         "crypto/x509"
  12         "encoding/base64"
  13         "encoding/json"
  14         "fmt"
  15         "math/big"
  16         "sync"
  17         "sync/atomic"
  18         "time"
  19
  20         "git.arvados.org/arvados.git/lib/cloud"
  21         "git.arvados.org/arvados.git/sdk/go/arvados"
  22         "github.com/aws/aws-sdk-go/aws"
  23         "github.com/aws/aws-sdk-go/aws/credentials"
  24         "github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds"
  25         "github.com/aws/aws-sdk-go/aws/ec2metadata"
  26         "github.com/aws/aws-sdk-go/aws/request"
  27         "github.com/aws/aws-sdk-go/aws/session"
  28         "github.com/aws/aws-sdk-go/service/ec2"
  29         "github.com/sirupsen/logrus"
  30         "golang.org/x/crypto/ssh"
  31 )
  32
  33 // Driver is the ec2 implementation of the cloud.Driver interface.
  34 var Driver = cloud.DriverFunc(newEC2InstanceSet)
  35
  36 const (
  37         throttleDelayMin = time.Second
  38         throttleDelayMax = time.Minute
  39 )
  40
  41 type ec2InstanceSetConfig struct {
  42         AccessKeyID      string
  43         SecretAccessKey  string
  44         Region           string
  45         SecurityGroupIDs arvados.StringSet
  46         SubnetID         string
  47         AdminUsername    string
  48         EBSVolumeType    string
  49 }
  50
  51 type ec2Interface interface {
  52         DescribeKeyPairs(input *ec2.DescribeKeyPairsInput) (*ec2.DescribeKeyPairsOutput, error)
  53         ImportKeyPair(input *ec2.ImportKeyPairInput) (*ec2.ImportKeyPairOutput, error)
  54         RunInstances(input *ec2.RunInstancesInput) (*ec2.Reservation, error)
  55         DescribeInstances(input *ec2.DescribeInstancesInput) (*ec2.DescribeInstancesOutput, error)
  56         CreateTags(input *ec2.CreateTagsInput) (*ec2.CreateTagsOutput, error)
  57         TerminateInstances(input *ec2.TerminateInstancesInput) (*ec2.TerminateInstancesOutput, error)
  58 }
  59
  60 type ec2InstanceSet struct {
  61         ec2config     ec2InstanceSetConfig
  62         instanceSetID cloud.InstanceSetID
  63         logger        logrus.FieldLogger
  64         client        ec2Interface
  65         keysMtx       sync.Mutex
  66         keys          map[string]string
  67         throttleDelay atomic.Value
  68 }
  69
  70 func newEC2InstanceSet(config json.RawMessage, instanceSetID cloud.InstanceSetID, _ cloud.SharedResourceTags, logger logrus.FieldLogger) (prv cloud.InstanceSet, err error) {
  71         instanceSet := &ec2InstanceSet{
  72                 instanceSetID: instanceSetID,
  73                 logger:        logger,
  74         }
  75         err = json.Unmarshal(config, &instanceSet.ec2config)
  76         if err != nil {
  77                 return nil, err
  78         }
  79
  80         sess, err := session.NewSession()
  81         if err != nil {
  82                 return nil, err
  83         }
  84         // First try any static credentials, fall back to an IAM instance profile/role
  85         creds := credentials.NewChainCredentials(
  86                 []credentials.Provider{
  87                         &credentials.StaticProvider{Value: credentials.Value{AccessKeyID: instanceSet.ec2config.AccessKeyID, SecretAccessKey: instanceSet.ec2config.SecretAccessKey}},
  88                         &ec2rolecreds.EC2RoleProvider{Client: ec2metadata.New(sess)},
  89                 })
  90
  91         awsConfig := aws.NewConfig().WithCredentials(creds).WithRegion(instanceSet.ec2config.Region)
  92         instanceSet.client = ec2.New(session.Must(session.NewSession(awsConfig)))
  93         instanceSet.keys = make(map[string]string)
  94         if instanceSet.ec2config.EBSVolumeType == "" {
  95                 instanceSet.ec2config.EBSVolumeType = "gp2"
  96         }
  97         return instanceSet, nil
  98 }
  99
 100 func awsKeyFingerprint(pk ssh.PublicKey) (md5fp string, sha1fp string, err error) {
 101         // AWS key fingerprints don't use the usual key fingerprint
 102         // you get from ssh-keygen or ssh.FingerprintLegacyMD5()
 103         // (you can get that from md5.Sum(pk.Marshal())
 104         //
 105         // AWS uses the md5 or sha1 of the PKIX DER encoding of the
 106         // public key, so calculate those fingerprints here.
 107         var rsaPub struct {
 108                 Name string
 109                 E    *big.Int
 110                 N    *big.Int
 111         }
 112         if err := ssh.Unmarshal(pk.Marshal(), &rsaPub); err != nil {
 113                 return "", "", fmt.Errorf("agent: Unmarshal failed to parse public key: %v", err)
 114         }
 115         rsaPk := rsa.PublicKey{
 116                 E: int(rsaPub.E.Int64()),
 117                 N: rsaPub.N,
 118         }
 119         pkix, _ := x509.MarshalPKIXPublicKey(&rsaPk)
 120         md5pkix := md5.Sum([]byte(pkix))
 121         sha1pkix := sha1.Sum([]byte(pkix))
 122         md5fp = ""
 123         sha1fp = ""
 124         for i := 0; i < len(md5pkix); i++ {
 125                 md5fp += fmt.Sprintf(":%02x", md5pkix[i])
 126         }
 127         for i := 0; i < len(sha1pkix); i++ {
 128                 sha1fp += fmt.Sprintf(":%02x", sha1pkix[i])
 129         }
 130         return md5fp[1:], sha1fp[1:], nil
 131 }
 132
 133 func (instanceSet *ec2InstanceSet) Create(
 134         instanceType arvados.InstanceType,
 135         imageID cloud.ImageID,
 136         newTags cloud.InstanceTags,
 137         initCommand cloud.InitCommand,
 138         publicKey ssh.PublicKey) (cloud.Instance, error) {
 139
 140         md5keyFingerprint, sha1keyFingerprint, err := awsKeyFingerprint(publicKey)
 141         if err != nil {
 142                 return nil, fmt.Errorf("Could not make key fingerprint: %v", err)
 143         }
 144         instanceSet.keysMtx.Lock()
 145         var keyname string
 146         var ok bool
 147         if keyname, ok = instanceSet.keys[md5keyFingerprint]; !ok {
 148                 keyout, err := instanceSet.client.DescribeKeyPairs(&ec2.DescribeKeyPairsInput{
 149                         Filters: []*ec2.Filter{{
 150                                 Name:   aws.String("fingerprint"),
 151                                 Values: []*string{&md5keyFingerprint, &sha1keyFingerprint},
 152                         }},
 153                 })
 154                 if err != nil {
 155                         return nil, fmt.Errorf("Could not search for keypair: %v", err)
 156                 }
 157
 158                 if len(keyout.KeyPairs) > 0 {
 159                         keyname = *(keyout.KeyPairs[0].KeyName)
 160                 } else {
 161                         keyname = "arvados-dispatch-keypair-" + md5keyFingerprint
 162                         _, err := instanceSet.client.ImportKeyPair(&ec2.ImportKeyPairInput{
 163                                 KeyName:           &keyname,
 164                                 PublicKeyMaterial: ssh.MarshalAuthorizedKey(publicKey),
 165                         })
 166                         if err != nil {
 167                                 return nil, fmt.Errorf("Could not import keypair: %v", err)
 168                         }
 169                 }
 170                 instanceSet.keys[md5keyFingerprint] = keyname
 171         }
 172         instanceSet.keysMtx.Unlock()
 173
 174         ec2tags := []*ec2.Tag{}
 175         for k, v := range newTags {
 176                 ec2tags = append(ec2tags, &ec2.Tag{
 177                         Key:   aws.String(k),
 178                         Value: aws.String(v),
 179                 })
 180         }
 181
 182         var groups []string
 183         for sg := range instanceSet.ec2config.SecurityGroupIDs {
 184                 groups = append(groups, sg)
 185         }
 186
 187         rii := ec2.RunInstancesInput{
 188                 ImageId:      aws.String(string(imageID)),
 189                 InstanceType: &instanceType.ProviderType,
 190                 MaxCount:     aws.Int64(1),
 191                 MinCount:     aws.Int64(1),
 192                 KeyName:      &keyname,
 193
 194                 NetworkInterfaces: []*ec2.InstanceNetworkInterfaceSpecification{
 195                         {
 196                                 AssociatePublicIpAddress: aws.Bool(false),
 197                                 DeleteOnTermination:      aws.Bool(true),
 198                                 DeviceIndex:              aws.Int64(0),
 199                                 Groups:                   aws.StringSlice(groups),
 200                                 SubnetId:                 &instanceSet.ec2config.SubnetID,
 201                         }},
 202                 DisableApiTermination:             aws.Bool(false),
 203                 InstanceInitiatedShutdownBehavior: aws.String("terminate"),
 204                 TagSpecifications: []*ec2.TagSpecification{
 205                         {
 206                                 ResourceType: aws.String("instance"),
 207                                 Tags:         ec2tags,
 208                         }},
 209                 UserData: aws.String(base64.StdEncoding.EncodeToString([]byte("#!/bin/sh\n" + initCommand + "\n"))),
 210         }
 211
 212         if instanceType.AddedScratch > 0 {
 213                 rii.BlockDeviceMappings = []*ec2.BlockDeviceMapping{{
 214                         DeviceName: aws.String("/dev/xvdt"),
 215                         Ebs: &ec2.EbsBlockDevice{
 216                                 DeleteOnTermination: aws.Bool(true),
 217                                 VolumeSize:          aws.Int64((int64(instanceType.AddedScratch) + (1<<30 - 1)) >> 30),
 218                                 VolumeType:          &instanceSet.ec2config.EBSVolumeType,
 219                         }}}
 220         }
 221
 222         if instanceType.Preemptible {
 223                 rii.InstanceMarketOptions = &ec2.InstanceMarketOptionsRequest{
 224                         MarketType: aws.String("spot"),
 225                         SpotOptions: &ec2.SpotMarketOptions{
 226                                 InstanceInterruptionBehavior: aws.String("terminate"),
 227                                 MaxPrice:                     aws.String(fmt.Sprintf("%v", instanceType.Price)),
 228                         }}
 229         }
 230
 231         rsv, err := instanceSet.client.RunInstances(&rii)
 232
 233         if request.IsErrorThrottle(err) {
 234                 // Back off exponentially until a create call either
 235                 // succeeds or returns a non-throttle error.
 236                 d, _ := instanceSet.throttleDelay.Load().(time.Duration)
 237                 d = d*3/2 + time.Second
 238                 if d < throttleDelayMin {
 239                         d = throttleDelayMin
 240                 } else if d > throttleDelayMax {
 241                         d = throttleDelayMax
 242                 }
 243                 instanceSet.throttleDelay.Store(d)
 244                 return nil, rateLimitError{error: err, earliestRetry: time.Now().Add(d)}
 245         } else if err != nil {
 246                 instanceSet.throttleDelay.Store(time.Duration(0))
 247                 return nil, err
 248         } else {
 249                 instanceSet.throttleDelay.Store(time.Duration(0))
 250         }
 251
 252         return &ec2Instance{
 253                 provider: instanceSet,
 254                 instance: rsv.Instances[0],
 255         }, nil
 256 }
 257
 258 func (instanceSet *ec2InstanceSet) Instances(tags cloud.InstanceTags) (instances []cloud.Instance, err error) {
 259         var filters []*ec2.Filter
 260         for k, v := range tags {
 261                 filters = append(filters, &ec2.Filter{
 262                         Name:   aws.String("tag:" + k),
 263                         Values: []*string{aws.String(v)},
 264                 })
 265         }
 266         dii := &ec2.DescribeInstancesInput{Filters: filters}
 267         for {
 268                 dio, err := instanceSet.client.DescribeInstances(dii)
 269                 if err != nil {
 270                         return nil, err
 271                 }
 272
 273                 for _, rsv := range dio.Reservations {
 274                         for _, inst := range rsv.Instances {
 275                                 if *inst.State.Name != "shutting-down" && *inst.State.Name != "terminated" {
 276                                         instances = append(instances, &ec2Instance{instanceSet, inst})
 277                                 }
 278                         }
 279                 }
 280                 if dio.NextToken == nil {
 281                         return instances, err
 282                 }
 283                 dii.NextToken = dio.NextToken
 284         }
 285 }
 286
 287 func (instanceSet *ec2InstanceSet) Stop() {
 288 }
 289
 290 type ec2Instance struct {
 291         provider *ec2InstanceSet
 292         instance *ec2.Instance
 293 }
 294
 295 func (inst *ec2Instance) ID() cloud.InstanceID {
 296         return cloud.InstanceID(*inst.instance.InstanceId)
 297 }
 298
 299 func (inst *ec2Instance) String() string {
 300         return *inst.instance.InstanceId
 301 }
 302
 303 func (inst *ec2Instance) ProviderType() string {
 304         return *inst.instance.InstanceType
 305 }
 306
 307 func (inst *ec2Instance) SetTags(newTags cloud.InstanceTags) error {
 308         var ec2tags []*ec2.Tag
 309         for k, v := range newTags {
 310                 ec2tags = append(ec2tags, &ec2.Tag{
 311                         Key:   aws.String(k),
 312                         Value: aws.String(v),
 313                 })
 314         }
 315
 316         _, err := inst.provider.client.CreateTags(&ec2.CreateTagsInput{
 317                 Resources: []*string{inst.instance.InstanceId},
 318                 Tags:      ec2tags,
 319         })
 320
 321         return err
 322 }
 323
 324 func (inst *ec2Instance) Tags() cloud.InstanceTags {
 325         tags := make(map[string]string)
 326
 327         for _, t := range inst.instance.Tags {
 328                 tags[*t.Key] = *t.Value
 329         }
 330
 331         return tags
 332 }
 333
 334 func (inst *ec2Instance) Destroy() error {
 335         _, err := inst.provider.client.TerminateInstances(&ec2.TerminateInstancesInput{
 336                 InstanceIds: []*string{inst.instance.InstanceId},
 337         })
 338         return err
 339 }
 340
 341 func (inst *ec2Instance) Address() string {
 342         if inst.instance.PrivateIpAddress != nil {
 343                 return *inst.instance.PrivateIpAddress
 344         }
 345         return ""
 346 }
 347
 348 func (inst *ec2Instance) RemoteUser() string {
 349         return inst.provider.ec2config.AdminUsername
 350 }
 351
 352 func (inst *ec2Instance) VerifyHostKey(ssh.PublicKey, *ssh.Client) error {
 353         return cloud.ErrNotImplemented
 354 }
 355
 356 type rateLimitError struct {
 357         error
 358         earliestRetry time.Time
 359 }
 360
 361 func (err rateLimitError) EarliestRetry() time.Time {
 362         return err.earliestRetry
 363 }