minio/pkg/storage/storage_bucket_policy.go
2015-03-08 15:57:20 -07:00

179 lines
3.3 KiB
Go

package storage
import (
"encoding/json"
"io"
"strings"
)
// User - AWS canonical
type User struct {
AWS string
}
// Statement - AWS policy statement
type Statement struct {
Sid string
Effect string
Principal User
Action []string
Resource []string
// TODO fix it in future if necessary - Condition {}
}
// BucketPolicy - AWS policy collection
type BucketPolicy struct {
Version string // date in 0000-00-00 format
Statement []Statement
}
// Resource delimiter
const (
AwsResource = "arn:aws:s3:::"
MinioResource = "minio:::"
)
// TODO support canonical user
// Principal delimiter
const (
AwsPrincipal = "arn:aws:iam::"
MinioPrincipal = "minio::"
)
// Action map
var SupportedActionMap = map[string]bool{
"*": true,
"s3:GetObject": true,
"s3:ListBucket": true,
"s3:PutObject": true,
"s3:CreateBucket": true,
"s3:GetBucketPolicy": true,
"s3:DeleteBucketPolicy": true,
"s3:ListAllMyBuckets": true,
"s3:PutBucketPolicy": true,
}
// Effect map
var SupportedEffectMap = map[string]bool{
"Allow": true,
"Deny": true,
}
func isValidAction(action []string) bool {
for _, a := range action {
if !SupportedActionMap[a] {
return false
}
}
return true
}
func isValidEffect(effect string) bool {
if SupportedEffectMap[effect] {
return true
}
return false
}
func isValidResource(resources []string) bool {
var ok bool
for _, resource := range resources {
switch true {
case strings.HasPrefix(resource, AwsResource):
bucket := strings.SplitAfter(resource, AwsResource)[1]
ok = true
if len(bucket) == 0 {
ok = false
}
case strings.HasPrefix(resource, MinioResource):
bucket := strings.SplitAfter(resource, MinioResource)[1]
ok = true
if len(bucket) == 0 {
ok = false
}
default:
ok = false
}
}
return ok
}
func isValidPrincipal(principal string) bool {
var ok bool
if principal == "*" {
return true
}
switch true {
case strings.HasPrefix(principal, AwsPrincipal):
username := strings.SplitAfter(principal, AwsPrincipal)[1]
ok = true
if len(username) == 0 {
ok = false
}
case strings.HasPrefix(principal, MinioPrincipal):
username := strings.SplitAfter(principal, MinioPrincipal)[1]
ok = true
if len(username) == 0 {
ok = false
}
default:
ok = false
}
return ok
}
// Parsepolicy - validate request body is proper JSON and in accordance with policy standards
func Parsepolicy(data io.Reader) (BucketPolicy, bool) {
var policy BucketPolicy
decoder := json.NewDecoder(data)
err := decoder.Decode(&policy)
if err != nil {
goto error
}
if len(policy.Version) == 0 {
goto error
}
_, err = parseDate(policy.Version)
if err != nil {
goto error
}
if len(policy.Statement) == 0 {
goto error
}
for _, statement := range policy.Statement {
if len(statement.Sid) == 0 {
goto error
}
if len(statement.Effect) == 0 {
goto error
}
if !isValidEffect(statement.Effect) {
goto error
}
if len(statement.Principal.AWS) == 0 {
goto error
}
if !isValidPrincipal(statement.Principal.AWS) {
goto error
}
if len(statement.Action) == 0 {
goto error
}
if !isValidAction(statement.Action) {
goto error
}
if len(statement.Resource) == 0 {
goto error
}
if !isValidResource(statement.Resource) {
goto error
}
}
return policy, true
error:
return BucketPolicy{}, false
}