open-vault/builtin/credential/aws-ec2/client.go
2016-09-23 21:35:36 -04:00

144 lines
4.4 KiB
Go

package awsec2
import (
"fmt"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/session"
"github.com/aws/aws-sdk-go/service/ec2"
"github.com/aws/aws-sdk-go/service/iam"
"github.com/hashicorp/go-cleanhttp"
"github.com/hashicorp/vault/helper/awsutil"
"github.com/hashicorp/vault/logical"
)
// getClientConfig creates a aws-sdk-go config, which is used to create client
// that can interact with AWS API. This builds credentials in the following
// order of preference:
//
// * Static credentials from 'config/client'
// * Environment variables
// * Instance metadata role
func (b *backend) getClientConfig(s logical.Storage, region string) (*aws.Config, error) {
credsConfig := &awsutil.CredentialsConfig{
Region: region,
}
// Read the configured secret key and access key
config, err := b.nonLockedClientConfigEntry(s)
if err != nil {
return nil, err
}
endpoint := aws.String("")
if config != nil {
// Override the default endpoint with the configured endpoint.
if config.Endpoint != "" {
endpoint = aws.String(config.Endpoint)
}
credsConfig.AccessKey = config.AccessKey
credsConfig.SecretKey = config.SecretKey
}
credsConfig.HTTPClient = cleanhttp.DefaultClient()
creds, err := credsConfig.GenerateCredentialChain()
if err != nil {
return nil, err
}
if creds == nil {
return nil, fmt.Errorf("could not compile valid credential providers from static config, environemnt, shared, or instance metadata")
}
// Create a config that can be used to make the API calls.
return &aws.Config{
Credentials: creds,
Region: aws.String(region),
HTTPClient: cleanhttp.DefaultClient(),
Endpoint: endpoint,
}, nil
}
// flushCachedEC2Clients deletes all the cached ec2 client objects from the backend.
// If the client credentials configuration is deleted or updated in the backend, all
// the cached EC2 client objects will be flushed. Config mutex lock should be
// acquired for write operation before calling this method.
func (b *backend) flushCachedEC2Clients() {
// deleting items in map during iteration is safe
for region, _ := range b.EC2ClientsMap {
delete(b.EC2ClientsMap, region)
}
}
// flushCachedIAMClients deletes all the cached iam client objects from the
// backend. If the client credentials configuration is deleted or updated in
// the backend, all the cached IAM client objects will be flushed. Config mutex
// lock should be acquired for write operation before calling this method.
func (b *backend) flushCachedIAMClients() {
// deleting items in map during iteration is safe
for region, _ := range b.IAMClientsMap {
delete(b.IAMClientsMap, region)
}
}
// clientEC2 creates a client to interact with AWS EC2 API
func (b *backend) clientEC2(s logical.Storage, region string) (*ec2.EC2, error) {
b.configMutex.RLock()
if b.EC2ClientsMap[region] != nil {
defer b.configMutex.RUnlock()
// If the client object was already created, return it
return b.EC2ClientsMap[region], nil
}
// Release the read lock and acquire the write lock
b.configMutex.RUnlock()
b.configMutex.Lock()
defer b.configMutex.Unlock()
// If the client gets created while switching the locks, return it
if b.EC2ClientsMap[region] != nil {
return b.EC2ClientsMap[region], nil
}
// Create an AWS config object using a chain of providers
awsConfig, err := b.getClientConfig(s, region)
if err != nil {
return nil, err
}
// Create a new EC2 client object, cache it and return the same
b.EC2ClientsMap[region] = ec2.New(session.New(awsConfig))
return b.EC2ClientsMap[region], nil
}
// clientIAM creates a client to interact with AWS IAM API
func (b *backend) clientIAM(s logical.Storage, region string) (*iam.IAM, error) {
b.configMutex.RLock()
if b.IAMClientsMap[region] != nil {
defer b.configMutex.RUnlock()
// If the client object was already created, return it
return b.IAMClientsMap[region], nil
}
// Release the read lock and acquire the write lock
b.configMutex.RUnlock()
b.configMutex.Lock()
defer b.configMutex.Unlock()
// If the client gets created while switching the locks, return it
if b.IAMClientsMap[region] != nil {
return b.IAMClientsMap[region], nil
}
// Create an AWS config object using a chain of providers
awsConfig, err := b.getClientConfig(s, region)
if err != nil {
return nil, err
}
// Create a new IAM client object, cache it and return the same
b.IAMClientsMap[region] = iam.New(session.New(awsConfig))
return b.IAMClientsMap[region], nil
}