diff --git a/aws/credentials/stscreds/assume_role_provider.go b/aws/credentials/stscreds/assume_role_provider.go index 0d1b5504700..b6dbfd2467d 100644 --- a/aws/credentials/stscreds/assume_role_provider.go +++ b/aws/credentials/stscreds/assume_role_provider.go @@ -87,6 +87,7 @@ import ( "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/internal/sdkrand" "github.com/aws/aws-sdk-go/service/sts" ) @@ -194,6 +195,18 @@ type AssumeRoleProvider struct { // // If ExpiryWindow is 0 or less it will be ignored. ExpiryWindow time.Duration + + // MaxJitterFrac reduces the effective Duration of each credential requested + // by a random percentage between 0 and MaxJitterFraction. MaxJitterFrac must + // have a value between 0 and 1. Any other value may lead to expected behavior. + // With a MaxJitterFrac value of 0, default) will no jitter will be used. + // + // For example, with a Duration of 30m and a MaxJitterFrac of 0.1, the + // AssumeRole call will be made with an arbitrary Duration between 27m and + // 30m. + // + // MaxJitterFrac should not be negative. + MaxJitterFrac float64 } // NewCredentials returns a pointer to a new Credentials object wrapping the @@ -255,8 +268,9 @@ func (p *AssumeRoleProvider) Retrieve() (credentials.Value, error) { // Expire as often as AWS permits. p.Duration = DefaultDuration } + jitter := time.Duration(sdkrand.SeededRand.Float64() * p.MaxJitterFrac * float64(p.Duration)) input := &sts.AssumeRoleInput{ - DurationSeconds: aws.Int64(int64(p.Duration / time.Second)), + DurationSeconds: aws.Int64(int64((p.Duration - jitter) / time.Second)), RoleArn: aws.String(p.RoleARN), RoleSessionName: aws.String(p.RoleSessionName), ExternalId: p.ExternalID,