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Diffstat (limited to 'vendor/github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds/ec2_role_provider.go')
-rw-r--r--vendor/github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds/ec2_role_provider.go178
1 files changed, 178 insertions, 0 deletions
diff --git a/vendor/github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds/ec2_role_provider.go b/vendor/github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds/ec2_role_provider.go
new file mode 100644
index 0000000..aa9d689
--- /dev/null
+++ b/vendor/github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds/ec2_role_provider.go
@@ -0,0 +1,178 @@
+package ec2rolecreds
+
+import (
+ "bufio"
+ "encoding/json"
+ "fmt"
+ "path"
+ "strings"
+ "time"
+
+ "github.com/aws/aws-sdk-go/aws/awserr"
+ "github.com/aws/aws-sdk-go/aws/client"
+ "github.com/aws/aws-sdk-go/aws/credentials"
+ "github.com/aws/aws-sdk-go/aws/ec2metadata"
+)
+
+// ProviderName provides a name of EC2Role provider
+const ProviderName = "EC2RoleProvider"
+
+// A EC2RoleProvider retrieves credentials from the EC2 service, and keeps track if
+// those credentials are expired.
+//
+// Example how to configure the EC2RoleProvider with custom http Client, Endpoint
+// or ExpiryWindow
+//
+// p := &ec2rolecreds.EC2RoleProvider{
+// // Pass in a custom timeout to be used when requesting
+// // IAM EC2 Role credentials.
+// Client: ec2metadata.New(sess, aws.Config{
+// HTTPClient: &http.Client{Timeout: 10 * time.Second},
+// }),
+//
+// // Do not use early expiry of credentials. If a non zero value is
+// // specified the credentials will be expired early
+// ExpiryWindow: 0,
+// }
+type EC2RoleProvider struct {
+ credentials.Expiry
+
+ // Required EC2Metadata client to use when connecting to EC2 metadata service.
+ Client *ec2metadata.EC2Metadata
+
+ // ExpiryWindow will allow the credentials to trigger refreshing prior to
+ // the credentials actually expiring. This is beneficial so race conditions
+ // with expiring credentials do not cause request to fail unexpectedly
+ // due to ExpiredTokenException exceptions.
+ //
+ // So a ExpiryWindow of 10s would cause calls to IsExpired() to return true
+ // 10 seconds before the credentials are actually expired.
+ //
+ // If ExpiryWindow is 0 or less it will be ignored.
+ ExpiryWindow time.Duration
+}
+
+// NewCredentials returns a pointer to a new Credentials object wrapping
+// the EC2RoleProvider. Takes a ConfigProvider to create a EC2Metadata client.
+// The ConfigProvider is satisfied by the session.Session type.
+func NewCredentials(c client.ConfigProvider, options ...func(*EC2RoleProvider)) *credentials.Credentials {
+ p := &EC2RoleProvider{
+ Client: ec2metadata.New(c),
+ }
+
+ for _, option := range options {
+ option(p)
+ }
+
+ return credentials.NewCredentials(p)
+}
+
+// NewCredentialsWithClient returns a pointer to a new Credentials object wrapping
+// the EC2RoleProvider. Takes a EC2Metadata client to use when connecting to EC2
+// metadata service.
+func NewCredentialsWithClient(client *ec2metadata.EC2Metadata, options ...func(*EC2RoleProvider)) *credentials.Credentials {
+ p := &EC2RoleProvider{
+ Client: client,
+ }
+
+ for _, option := range options {
+ option(p)
+ }
+
+ return credentials.NewCredentials(p)
+}
+
+// Retrieve retrieves credentials from the EC2 service.
+// Error will be returned if the request fails, or unable to extract
+// the desired credentials.
+func (m *EC2RoleProvider) Retrieve() (credentials.Value, error) {
+ credsList, err := requestCredList(m.Client)
+ if err != nil {
+ return credentials.Value{ProviderName: ProviderName}, err
+ }
+
+ if len(credsList) == 0 {
+ return credentials.Value{ProviderName: ProviderName}, awserr.New("EmptyEC2RoleList", "empty EC2 Role list", nil)
+ }
+ credsName := credsList[0]
+
+ roleCreds, err := requestCred(m.Client, credsName)
+ if err != nil {
+ return credentials.Value{ProviderName: ProviderName}, err
+ }
+
+ m.SetExpiration(roleCreds.Expiration, m.ExpiryWindow)
+
+ return credentials.Value{
+ AccessKeyID: roleCreds.AccessKeyID,
+ SecretAccessKey: roleCreds.SecretAccessKey,
+ SessionToken: roleCreds.Token,
+ ProviderName: ProviderName,
+ }, nil
+}
+
+// A ec2RoleCredRespBody provides the shape for unmarshalling credential
+// request responses.
+type ec2RoleCredRespBody struct {
+ // Success State
+ Expiration time.Time
+ AccessKeyID string
+ SecretAccessKey string
+ Token string
+
+ // Error state
+ Code string
+ Message string
+}
+
+const iamSecurityCredsPath = "/iam/security-credentials"
+
+// requestCredList requests a list of credentials from the EC2 service.
+// If there are no credentials, or there is an error making or receiving the request
+func requestCredList(client *ec2metadata.EC2Metadata) ([]string, error) {
+ resp, err := client.GetMetadata(iamSecurityCredsPath)
+ if err != nil {
+ return nil, awserr.New("EC2RoleRequestError", "no EC2 instance role found", err)
+ }
+
+ credsList := []string{}
+ s := bufio.NewScanner(strings.NewReader(resp))
+ for s.Scan() {
+ credsList = append(credsList, s.Text())
+ }
+
+ if err := s.Err(); err != nil {
+ return nil, awserr.New("SerializationError", "failed to read EC2 instance role from metadata service", err)
+ }
+
+ return credsList, nil
+}
+
+// requestCred requests the credentials for a specific credentials from the EC2 service.
+//
+// If the credentials cannot be found, or there is an error reading the response
+// and error will be returned.
+func requestCred(client *ec2metadata.EC2Metadata, credsName string) (ec2RoleCredRespBody, error) {
+ resp, err := client.GetMetadata(path.Join(iamSecurityCredsPath, credsName))
+ if err != nil {
+ return ec2RoleCredRespBody{},
+ awserr.New("EC2RoleRequestError",
+ fmt.Sprintf("failed to get %s EC2 instance role credentials", credsName),
+ err)
+ }
+
+ respCreds := ec2RoleCredRespBody{}
+ if err := json.NewDecoder(strings.NewReader(resp)).Decode(&respCreds); err != nil {
+ return ec2RoleCredRespBody{},
+ awserr.New("SerializationError",
+ fmt.Sprintf("failed to decode %s EC2 instance role credentials", credsName),
+ err)
+ }
+
+ if respCreds.Code != "Success" {
+ // If an error code was returned something failed requesting the role.
+ return ec2RoleCredRespBody{}, awserr.New(respCreds.Code, respCreds.Message, nil)
+ }
+
+ return respCreds, nil
+}