minio/internal/arn/arn.go
2022-01-02 09:15:06 -08:00

146 lines
3.6 KiB
Go

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package arn
import (
"fmt"
"regexp"
"strings"
)
// ARN structure:
//
// arn:partition:service:region:account-id:resource-type/resource-id
//
// In this implementation, account-id is empty.
//
// Reference: https://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html
type arnPartition string
const (
arnPartitionMinio arnPartition = "minio"
)
type arnService string
const (
arnServiceIAM arnService = "iam"
)
type arnResourceType string
const (
arnResourceTypeRole arnResourceType = "role"
)
// ARN - representation of resources based on AWS ARNs.
type ARN struct {
Partition arnPartition
Service arnService
Region string
ResourceType arnResourceType
ResourceID string
}
// Allows english letters, numbers, '.', '-', '_' and '/'. Starts with a
// letter or digit. At least 1 character long.
var validResourceIDRegex = regexp.MustCompile(`^[A-Za-z0-9][A-Za-z0-9_/\.-]*$`)
// NewIAMRoleARN - returns an ARN for a role in MinIO.
func NewIAMRoleARN(resourceID, serverRegion string) (ARN, error) {
if !validResourceIDRegex.MatchString(resourceID) {
return ARN{}, fmt.Errorf("Invalid resource ID: %s", resourceID)
}
return ARN{
Partition: arnPartitionMinio,
Service: arnServiceIAM,
Region: serverRegion,
ResourceType: arnResourceTypeRole,
ResourceID: resourceID,
}, nil
}
// String - returns string representation of the ARN.
func (arn ARN) String() string {
return strings.Join(
[]string{
"arn",
string(arn.Partition),
string(arn.Service),
arn.Region,
"", // account-id is always empty in this implementation
string(arn.ResourceType) + "/" + arn.ResourceID,
},
":",
)
}
// Parse - parses an ARN string into a type.
func Parse(arnStr string) (arn ARN, err error) {
ps := strings.Split(arnStr, ":")
if len(ps) != 6 ||
ps[0] != "arn" {
err = fmt.Errorf("Invalid ARN string format")
return
}
if ps[1] != string(arnPartitionMinio) {
err = fmt.Errorf("Invalid ARN - bad partition field")
return
}
if ps[2] != string(arnServiceIAM) {
err = fmt.Errorf("Invalid ARN - bad service field")
return
}
// ps[3] is region and is not validated here. If the region is invalid,
// the ARN would not match any configured ARNs in the server.
if ps[4] != "" {
err = fmt.Errorf("Invalid ARN - unsupported account-id field")
return
}
res := strings.SplitN(ps[5], "/", 2)
if len(res) != 2 {
err = fmt.Errorf("Invalid ARN - resource does not contain a \"/\"")
return
}
if res[0] != string(arnResourceTypeRole) {
err = fmt.Errorf("Invalid ARN: resource type is invalid.")
return
}
if !validResourceIDRegex.MatchString(res[1]) {
err = fmt.Errorf("Invalid resource ID: %s", res[1])
return
}
arn = ARN{
Partition: arnPartitionMinio,
Service: arnServiceIAM,
Region: ps[3],
ResourceType: arnResourceTypeRole,
ResourceID: res[1],
}
return
}