consul/agent/connect/ca/provider_vault_auth_aws.go

116 lines
4.1 KiB
Go

package ca
import (
"fmt"
"os"
"strconv"
"github.com/aws/aws-sdk-go/aws/credentials"
"github.com/hashicorp/go-cleanhttp"
"github.com/hashicorp/go-hclog"
"github.com/hashicorp/go-secure-stdlib/awsutil"
"github.com/hashicorp/consul/agent/structs"
)
// NewAWSAuthClient returns a VaultAuthClient that can log into Vault using the AWS auth method.
func NewAWSAuthClient(authMethod *structs.VaultAuthMethod) *VaultAuthClient {
authClient := NewVaultAPIAuthClient(authMethod, "")
// Inspect the config params to see if they are already in the format required for
// the auth/aws/login API call. If so, we want to call the login API with the params
// exactly as they are configured. This supports the Vault CA config in a backwards
// compatible way so that we don't break existing configurations.
keys := []string{
"identity", // EC2 identity
"pkcs7", // EC2 PKCS7
"iam_http_request_method", // IAM
}
if legacyCheck(authMethod.Params, keys...) {
return authClient
}
// None of the known config is present so use the login data generator to transform
// the auth method config params into the login data request needed to authenticate
// via AWS.
lgd := &AWSLoginDataGenerator{}
authClient.LoginDataGen = lgd.GenerateLoginData
return authClient
}
// AWSLoginDataGenerator is a LoginDataGenerator for AWS authentication.
type AWSLoginDataGenerator struct {
// credentials supports explicitly setting the AWS credentials to use for authenticating with AWS.
// It is un-exported and intended for testing purposes only.
credentials *credentials.Credentials
}
// GenerateLoginData derives the login data for the Vault AWS auth login request from the CA
// provider auth method config.
func (g *AWSLoginDataGenerator) GenerateLoginData(authMethod *structs.VaultAuthMethod) (map[string]interface{}, error) {
// Create the credential configuration from the parameters.
credsConfig, headerValue, err := newAWSCredentialsConfig(authMethod.Params)
if err != nil {
return nil, fmt.Errorf("aws auth failed to create credential configuration: %w", err)
}
// Use the provided credentials if they are present.
creds := g.credentials
if creds == nil {
// Generate the credential chain
creds, err = credsConfig.GenerateCredentialChain()
if err != nil {
return nil, fmt.Errorf("aws auth failed to generate credential chain: %w", err)
}
}
// Derive the login data
loginData, err := awsutil.GenerateLoginData(creds, headerValue, credsConfig.Region, hclog.NewNullLogger())
if err != nil {
return nil, fmt.Errorf("aws auth failed to generate login data: %w", err)
}
return loginData, nil
}
// newAWSCredentialsConfig creates an awsutil.CredentialsConfig from the given set of parameters.
// It is mostly copied from the awsutil package because that package does not currently provide
// an easy way to configure all the available options.
func newAWSCredentialsConfig(config map[string]interface{}) (*awsutil.CredentialsConfig, string, error) {
params, err := toMapStringString(config)
if err != nil {
return nil, "", fmt.Errorf("misconfiguration of AWS auth parameters: %w", err)
}
// Populate the AWS credentials configuration. Empty strings will use the defaults.
c := &awsutil.CredentialsConfig{
AccessKey: params["access_key"],
SecretKey: params["secret_key"],
SessionToken: params["session_token"],
IAMEndpoint: params["iam_endpoint"],
STSEndpoint: params["sts_endpoint"],
Region: params["region"],
Filename: params["filename"],
Profile: params["profile"],
RoleARN: params["role_arn"],
RoleSessionName: params["role_session_name"],
WebIdentityTokenFile: params["web_identity_token_file"],
HTTPClient: cleanhttp.DefaultClient(),
}
if maxRetries, err := strconv.Atoi(params["max_retries"]); err == nil {
c.MaxRetries = &maxRetries
}
if c.Region == "" {
c.Region = os.Getenv("AWS_REGION")
if c.Region == "" {
c.Region = os.Getenv("AWS_DEFAULT_REGION")
if c.Region == "" {
c.Region = "us-east-1"
}
}
}
return c, params["header_value"], nil
}