frostfs-node/pkg/services/common/ape/checker.go
Airat Arifullin a812932984 [#1362] ape: Move common APE check logic to separate package
* Tree and object service have the same log for checking APE. So,
  this check should be moved to common package.

Signed-off-by: Airat Arifullin <a.arifullin@yadro.com>
2024-09-10 12:40:34 +00:00

167 lines
5.9 KiB
Go

package ape
import (
"crypto/ecdsa"
"errors"
"fmt"
aperequest "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/ape/request"
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/ape/router"
frostfsidcore "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/core/frostfsid"
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/core/netmap"
"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/ape"
"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/bearer"
apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/user"
apechain "git.frostfs.info/TrueCloudLab/policy-engine/pkg/chain"
policyengine "git.frostfs.info/TrueCloudLab/policy-engine/pkg/engine"
"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
)
var (
errInvalidTargetType = errors.New("bearer token defines non-container target override")
errBearerExpired = errors.New("bearer token has expired")
errBearerInvalidSignature = errors.New("bearer token has invalid signature")
errBearerInvalidContainerID = errors.New("bearer token was created for another container")
errBearerNotSignedByOwner = errors.New("bearer token is not signed by the container owner")
errBearerInvalidOwner = errors.New("bearer token owner differs from the request sender")
)
type CheckPrm struct {
// Request is an APE-request that is checked by policy engine.
Request aperequest.Request
Namespace string
Container cid.ID
// An encoded container's owner user ID.
ContainerOwner user.ID
// PublicKey is public key of the request sender.
PublicKey *keys.PublicKey
// The request's bearer token. It is used in order to check APE overrides with the token.
BearerToken *bearer.Token
// If SoftAPECheck is set to true, then NoRuleFound is interpreted as allow.
SoftAPECheck bool
}
// CheckCore provides methods to perform the common logic of APE check.
type CheckCore interface {
// CheckAPE performs the common policy-engine check logic on a prepared request.
CheckAPE(prm CheckPrm) error
}
type checkerCoreImpl struct {
LocalOverrideStorage policyengine.LocalOverrideStorage
MorphChainStorage policyengine.MorphRuleChainStorageReader
FrostFSSubjectProvider frostfsidcore.SubjectProvider
State netmap.State
}
func New(localOverrideStorage policyengine.LocalOverrideStorage, morphChainStorage policyengine.MorphRuleChainStorageReader,
frostFSSubjectProvider frostfsidcore.SubjectProvider, state netmap.State) CheckCore {
return &checkerCoreImpl{
LocalOverrideStorage: localOverrideStorage,
MorphChainStorage: morphChainStorage,
FrostFSSubjectProvider: frostFSSubjectProvider,
State: state,
}
}
// CheckAPE performs the common policy-engine check logic on a prepared request.
func (c *checkerCoreImpl) CheckAPE(prm CheckPrm) error {
var cr policyengine.ChainRouter
if prm.BearerToken != nil && !prm.BearerToken.Impersonate() {
var err error
if err = isValidBearer(prm.BearerToken, prm.ContainerOwner, prm.Container, prm.PublicKey, c.State); err != nil {
return fmt.Errorf("bearer validation error: %w", err)
}
cr, err = router.BearerChainFeedRouter(c.LocalOverrideStorage, c.MorphChainStorage, prm.BearerToken.APEOverride())
if err != nil {
return fmt.Errorf("create chain router error: %w", err)
}
} else {
cr = policyengine.NewDefaultChainRouterWithLocalOverrides(c.MorphChainStorage, c.LocalOverrideStorage)
}
groups, err := aperequest.Groups(c.FrostFSSubjectProvider, prm.PublicKey)
if err != nil {
return fmt.Errorf("failed to get group ids: %w", err)
}
// Policy contract keeps group related chains as namespace-group pair.
for i := range groups {
groups[i] = fmt.Sprintf("%s:%s", prm.Namespace, groups[i])
}
rt := policyengine.NewRequestTargetExtended(prm.Namespace, prm.Container.EncodeToString(), fmt.Sprintf("%s:%s", prm.Namespace, prm.PublicKey.Address()), groups)
status, found, err := cr.IsAllowed(apechain.Ingress, rt, prm.Request)
if err != nil {
return err
}
if !found && prm.SoftAPECheck || status == apechain.Allow {
return nil
}
err = fmt.Errorf("access to operation %s is denied by access policy engine: %s", prm.Request.Operation(), status.String())
return apeErr(err)
}
func apeErr(err error) error {
errAccessDenied := &apistatus.ObjectAccessDenied{}
errAccessDenied.WriteReason(err.Error())
return errAccessDenied
}
// isValidBearer checks whether bearer token was correctly signed by authorized
// entity. This method might be defined on whole ACL service because it will
// require fetching current epoch to check lifetime.
func isValidBearer(token *bearer.Token, ownerCnr user.ID, cntID cid.ID, publicKey *keys.PublicKey, st netmap.State) error {
if token == nil {
return nil
}
// First check token lifetime. Simplest verification.
if token.InvalidAt(st.CurrentEpoch()) {
return errBearerExpired
}
// Then check if bearer token is signed correctly.
if !token.VerifySignature() {
return errBearerInvalidSignature
}
// Check for ape overrides defined in the bearer token.
apeOverride := token.APEOverride()
if len(apeOverride.Chains) > 0 && apeOverride.Target.TargetType != ape.TargetTypeContainer {
return fmt.Errorf("%w: %s", errInvalidTargetType, apeOverride.Target.TargetType.ToV2().String())
}
// Then check if container is either empty or equal to the container in the request.
var targetCnr cid.ID
err := targetCnr.DecodeString(apeOverride.Target.Name)
if err != nil {
return fmt.Errorf("invalid cid format: %s", apeOverride.Target.Name)
}
if !cntID.Equals(targetCnr) {
return errBearerInvalidContainerID
}
// Then check if container owner signed this token.
if !bearer.ResolveIssuer(*token).Equals(ownerCnr) {
return errBearerNotSignedByOwner
}
// Then check if request sender has rights to use this token.
var usrSender user.ID
user.IDFromKey(&usrSender, (ecdsa.PublicKey)(*publicKey))
if !token.AssertUser(usrSender) {
return errBearerInvalidOwner
}
return nil
}