minio/cmd/sts-handlers.go
Harshavardhana 1af6e8cb72
Add support for session policies in STS APIs (#7747)
This PR adds support for adding session policies
for further restrictions on STS credentials, useful
in situations when applications want to generate
creds for multiple interested parties with different
set of policy restrictions.

This session policy is not mandatory, but optional.

Fixes #7732
2019-06-20 15:28:33 -07:00

406 lines
13 KiB
Go

/*
* MinIO Cloud Storage, (C) 2018, 2019 MinIO, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cmd
import (
"bytes"
"context"
"encoding/base64"
"fmt"
"net/http"
"github.com/gorilla/mux"
"github.com/minio/minio/cmd/logger"
"github.com/minio/minio/pkg/auth"
iampolicy "github.com/minio/minio/pkg/iam/policy"
"github.com/minio/minio/pkg/iam/validator"
"github.com/minio/minio/pkg/wildcard"
)
const (
// STS API version.
stsAPIVersion = "2011-06-15"
// STS API action constants
clientGrants = "AssumeRoleWithClientGrants"
webIdentity = "AssumeRoleWithWebIdentity"
assumeRole = "AssumeRole"
)
// stsAPIHandlers implements and provides http handlers for AWS STS API.
type stsAPIHandlers struct{}
// registerSTSRouter - registers AWS STS compatible APIs.
func registerSTSRouter(router *mux.Router) {
// Initialize STS.
sts := &stsAPIHandlers{}
// STS Router
stsRouter := router.NewRoute().PathPrefix("/").Subrouter()
// Assume roles with no JWT, handles AssumeRole.
stsRouter.Methods("POST").MatcherFunc(func(r *http.Request, rm *mux.RouteMatch) bool {
ctypeOk := wildcard.MatchSimple("application/x-www-form-urlencoded*", r.Header.Get("Content-Type"))
authOk := wildcard.MatchSimple("AWS4-HMAC-SHA256*", r.Header.Get("Authorization"))
noQueries := len(r.URL.Query()) == 0
return ctypeOk && authOk && noQueries
}).HandlerFunc(httpTraceAll(sts.AssumeRole))
// Assume roles with JWT handler, handles both ClientGrants and WebIdentity.
stsRouter.Methods("POST").MatcherFunc(func(r *http.Request, rm *mux.RouteMatch) bool {
ctypeOk := wildcard.MatchSimple("application/x-www-form-urlencoded*", r.Header.Get("Content-Type"))
noQueries := len(r.URL.Query()) == 0
return ctypeOk && noQueries
}).HandlerFunc(httpTraceAll(sts.AssumeRoleWithJWT))
// AssumeRoleWithClientGrants
stsRouter.Methods("POST").HandlerFunc(httpTraceAll(sts.AssumeRoleWithClientGrants)).
Queries("Action", clientGrants).
Queries("Version", stsAPIVersion).
Queries("Token", "{Token:.*}")
// AssumeRoleWithWebIdentity
stsRouter.Methods("POST").HandlerFunc(httpTraceAll(sts.AssumeRoleWithWebIdentity)).
Queries("Action", webIdentity).
Queries("Version", stsAPIVersion).
Queries("WebIdentityToken", "{Token:.*}")
}
func checkAssumeRoleAuth(ctx context.Context, r *http.Request) (user auth.Credentials, stsErr STSErrorCode) {
switch getRequestAuthType(r) {
default:
return user, ErrSTSAccessDenied
case authTypeSigned:
s3Err := isReqAuthenticated(ctx, r, globalServerConfig.GetRegion(), serviceSTS)
if STSErrorCode(s3Err) != ErrSTSNone {
return user, STSErrorCode(s3Err)
}
var owner bool
user, owner, s3Err = getReqAccessKeyV4(r, globalServerConfig.GetRegion(), serviceSTS)
if STSErrorCode(s3Err) != ErrSTSNone {
return user, STSErrorCode(s3Err)
}
// Root credentials are not allowed to use STS API
if owner {
return user, ErrSTSAccessDenied
}
}
// Session tokens are not allowed in STS AssumeRole requests.
if getSessionToken(r) != "" {
return user, ErrSTSAccessDenied
}
return user, ErrSTSNone
}
// AssumeRole - implementation of AWS STS API AssumeRole to get temporary
// credentials for regular users on Minio.
// https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html
func (sts *stsAPIHandlers) AssumeRole(w http.ResponseWriter, r *http.Request) {
ctx := newContext(r, w, "AssumeRole")
user, stsErr := checkAssumeRoleAuth(ctx, r)
if stsErr != ErrSTSNone {
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(stsErr))
return
}
if err := r.ParseForm(); err != nil {
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
if r.Form.Get("Version") != stsAPIVersion {
logger.LogIf(ctx, fmt.Errorf("Invalid STS API version %s, expecting %s", r.Form.Get("Version"), stsAPIVersion))
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSMissingParameter))
return
}
action := r.Form.Get("Action")
switch action {
case assumeRole:
default:
logger.LogIf(ctx, fmt.Errorf("Unsupported action %s", action))
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
ctx = newContext(r, w, action)
defer logger.AuditLog(w, r, action, nil)
sessionPolicyStr := r.Form.Get("Policy")
// https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html
// The plain text that you use for both inline and managed session
// policies shouldn't exceed 2048 characters.
if len(sessionPolicyStr) > 2048 {
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
if len(sessionPolicyStr) > 0 {
sessionPolicy, err := iampolicy.ParseConfig(bytes.NewReader([]byte(sessionPolicyStr)))
if err != nil {
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
// Version in policy must not be empty
if sessionPolicy.Version == "" {
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
}
var err error
m := make(map[string]interface{})
m["exp"], err = validator.GetDefaultExpiration(r.Form.Get("DurationSeconds"))
if err != nil {
switch err {
case validator.ErrInvalidDuration:
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
default:
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
}
return
}
policyName, err := globalIAMSys.GetUserPolicy(user.AccessKey)
if err != nil {
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
// This policy is the policy associated with the user
// requesting for temporary credentials. The temporary
// credentials will inherit the same policy requirements.
m[iampolicy.PolicyName] = policyName
if len(sessionPolicyStr) > 0 {
m[iampolicy.SessionPolicyName] = base64.StdEncoding.EncodeToString([]byte(sessionPolicyStr))
}
secret := globalServerConfig.GetCredential().SecretKey
cred, err := auth.GetNewCredentialsWithMetadata(m, secret)
if err != nil {
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInternalError))
return
}
// Set the newly generated credentials.
if err = globalIAMSys.SetTempUser(cred.AccessKey, cred, policyName); err != nil {
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInternalError))
return
}
// Notify all other MinIO peers to reload temp users
for _, nerr := range globalNotificationSys.LoadUser(cred.AccessKey, true) {
if nerr.Err != nil {
logger.GetReqInfo(ctx).SetTags("peerAddress", nerr.Host.String())
logger.LogIf(ctx, nerr.Err)
}
}
assumeRoleResponse := &AssumeRoleResponse{
Result: AssumeRoleResult{
Credentials: cred,
},
}
assumeRoleResponse.ResponseMetadata.RequestID = w.Header().Get(responseRequestIDKey)
writeSuccessResponseXML(w, encodeResponse(assumeRoleResponse))
}
func (sts *stsAPIHandlers) AssumeRoleWithJWT(w http.ResponseWriter, r *http.Request) {
ctx := newContext(r, w, "AssumeRoleJWTCommon")
// Parse the incoming form data.
if err := r.ParseForm(); err != nil {
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
if r.Form.Get("Version") != stsAPIVersion {
logger.LogIf(ctx, fmt.Errorf("Invalid STS API version %s, expecting %s", r.Form.Get("Version"), stsAPIVersion))
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSMissingParameter))
return
}
action := r.Form.Get("Action")
switch action {
case clientGrants, webIdentity:
default:
logger.LogIf(ctx, fmt.Errorf("Unsupported action %s", action))
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
ctx = newContext(r, w, action)
defer logger.AuditLog(w, r, action, nil)
if globalIAMValidators == nil {
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSNotInitialized))
return
}
v, err := globalIAMValidators.Get("jwt")
if err != nil {
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
token := r.Form.Get("Token")
if token == "" {
token = r.Form.Get("WebIdentityToken")
}
m, err := v.Validate(token, r.Form.Get("DurationSeconds"))
if err != nil {
switch err {
case validator.ErrTokenExpired:
switch action {
case clientGrants:
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSClientGrantsExpiredToken))
case webIdentity:
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSWebIdentityExpiredToken))
}
return
case validator.ErrInvalidDuration:
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
sessionPolicyStr := r.Form.Get("Policy")
// https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRoleWithWebIdentity.html
// The plain text that you use for both inline and managed session
// policies shouldn't exceed 2048 characters.
if len(sessionPolicyStr) > 2048 {
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
if len(sessionPolicyStr) > 0 {
sessionPolicy, err := iampolicy.ParseConfig(bytes.NewReader([]byte(sessionPolicyStr)))
if err != nil {
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
// Version in policy must not be empty
if sessionPolicy.Version == "" {
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInvalidParameterValue))
return
}
}
secret := globalServerConfig.GetCredential().SecretKey
cred, err := auth.GetNewCredentialsWithMetadata(m, secret)
if err != nil {
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInternalError))
return
}
// JWT has requested a custom claim with policy value set.
// This is a MinIO STS API specific value, this value should
// be set and configured on your identity provider as part of
// JWT custom claims.
var policyName string
if v, ok := m[iampolicy.PolicyName]; ok {
policyName, _ = v.(string)
}
var subFromToken string
if v, ok := m["sub"]; ok {
subFromToken, _ = v.(string)
}
if len(sessionPolicyStr) > 0 {
m[iampolicy.SessionPolicyName] = base64.StdEncoding.EncodeToString([]byte(sessionPolicyStr))
}
// Set the newly generated credentials.
if err = globalIAMSys.SetTempUser(cred.AccessKey, cred, policyName); err != nil {
logger.LogIf(ctx, err)
writeSTSErrorResponse(w, stsErrCodes.ToSTSErr(ErrSTSInternalError))
return
}
// Notify all other MinIO peers to reload temp users
for _, nerr := range globalNotificationSys.LoadUser(cred.AccessKey, true) {
if nerr.Err != nil {
logger.GetReqInfo(ctx).SetTags("peerAddress", nerr.Host.String())
logger.LogIf(ctx, nerr.Err)
}
}
var encodedSuccessResponse []byte
switch action {
case clientGrants:
clientGrantsResponse := &AssumeRoleWithClientGrantsResponse{
Result: ClientGrantsResult{
Credentials: cred,
SubjectFromToken: subFromToken,
},
}
clientGrantsResponse.ResponseMetadata.RequestID = w.Header().Get(responseRequestIDKey)
encodedSuccessResponse = encodeResponse(clientGrantsResponse)
case webIdentity:
webIdentityResponse := &AssumeRoleWithWebIdentityResponse{
Result: WebIdentityResult{
Credentials: cred,
SubjectFromWebIdentityToken: subFromToken,
},
}
webIdentityResponse.ResponseMetadata.RequestID = w.Header().Get(responseRequestIDKey)
encodedSuccessResponse = encodeResponse(webIdentityResponse)
}
writeSuccessResponseXML(w, encodedSuccessResponse)
}
// AssumeRoleWithWebIdentity - implementation of AWS STS API supporting OAuth2.0
// users from web identity provider such as Facebook, Google, or any OpenID
// Connect-compatible identity provider.
//
// Eg:-
// $ curl https://minio:9000/?Action=AssumeRoleWithWebIdentity&WebIdentityToken=<jwt>
func (sts *stsAPIHandlers) AssumeRoleWithWebIdentity(w http.ResponseWriter, r *http.Request) {
sts.AssumeRoleWithJWT(w, r)
}
// AssumeRoleWithClientGrants - implementation of AWS STS extension API supporting
// OAuth2.0 client credential grants.
//
// Eg:-
// $ curl https://minio:9000/?Action=AssumeRoleWithClientGrants&Token=<jwt>
func (sts *stsAPIHandlers) AssumeRoleWithClientGrants(w http.ResponseWriter, r *http.Request) {
sts.AssumeRoleWithJWT(w, r)
}