ziti/controller/model/ca_manager.go

/*
	Copyright NetFoundry 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

	https://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 model

import (
	"crypto/x509"
	"fmt"
	"strings"
	"sync"
	"time"

	"github.com/jellydator/ttlcache/v3"
	"github.com/michaelquigley/pfxlog"
	nfpem "github.com/openziti/foundation/v2/pem"
	"github.com/openziti/identity"
	"github.com/openziti/ziti/v2/controller/storage/ast"
	"github.com/openziti/ziti/v2/controller/storage/boltz"
	"github.com/openziti/ziti/v2/common/pb/edge_cmd_pb"
	"github.com/openziti/ziti/v2/controller/change"
	"github.com/openziti/ziti/v2/controller/command"
	"github.com/openziti/ziti/v2/controller/db"
	"github.com/openziti/ziti/v2/controller/fields"
	"github.com/openziti/ziti/v2/controller/models"
	"go.etcd.io/bbolt"
	"google.golang.org/protobuf/proto"
)

func NewCaManager(env Env) *CaManager {
	manager := &CaManager{
		baseEntityManager: newBaseEntityManager[*Ca, *db.Ca](env, env.GetStores().Ca),
	}
	manager.impl = manager

	RegisterManagerDecoder[*Ca](env, manager)

	env.GetStores().Ca.AddEntityEventListenerF(manager.onMutate, boltz.EntityDeletedAsync)
	env.GetStores().Ca.AddEntityEventListenerF(manager.onMutate, boltz.EntityCreatedAsync)
	env.GetStores().Ca.AddEntityEventListenerF(manager.onMutate, boltz.EntityUpdatedAsync)

	return manager
}

const certVerifyCacheTTL = 10 * time.Minute

type TrustCache struct {
	// static root certificates from the controller's root identity CA bundle (roots and intermediates)
	staticFirstPartyTrustAnchors []*x509.Certificate

	// a cert pool that mirrors `staticFirstPartyTrustAnchors`
	staticFirstPartyTrustAnchorPool *x509.CertPool

	// static root certificates from the controller's root identity CA bundle (roots only)
	staticFirstPartyRoots []*x509.Certificate

	// a cert pool that mirrors `staticFirstPartyRoots`
	staticFirstPartyRootPool *x509.CertPool

	// a set of trust anchors registered as 3rd party CAs that are active for authentication
	thirdPartyTrustAnchors []*x509.Certificate

	// a cert pool that mirrors `thirdPartyTrustAnchors`
	thirdPartyTrustAnchorPool *x509.CertPool

	// all 3rd party CA model items in fingerprint -> Ca form
	activeThirdPartyCas map[string]*Ca

	// a pool of all roots, intermediates and 3rd parties
	allPool *x509.CertPool

	// certOriginCache caches cert chain verification results by fingerprint, avoiding repeated
	// x509.Verify calls for the same certificate. TLS handshake guarantees private key possession
	// per-connection, so caching the chain verification result is safe.
	certOriginCache *ttlcache.Cache[string, CertOrigin]

	sync.RWMutex
	initOnce sync.Once
}

// CertOrigin indicates whether a client certificate was issued by a first-party (internal) CA
// or a third-party CA. This distinction is used to gate SPIFFE ID matching, which is only
// valid for first-party certificates.
type CertOrigin int

const (
	CertOriginUntrusted CertOrigin = iota
	CertOriginFirstParty
	CertOriginThirdParty
)

func (self *TrustCache) GetAllPool() *x509.CertPool {
	self.RLock()
	defer self.RUnlock()

	if self.allPool == nil {
		return x509.NewCertPool()
	}

	return self.allPool
}

// VerifyClientCert verifies a client certificate chain against the tiered trust pools and returns
// which pool matched. First-party pools (roots, then roots+intermediates) are tried first, then
// third-party. Returns CertOriginUntrusted if no pool validates the cert.
//
// When skipTimeCheck is true, certificate time validity (NotBefore/NotAfter) is bypassed during
// chain verification. This supports auth policies that allow expired certificates. The caller
// is responsible for enforcing expiry when appropriate.
func (self *TrustCache) VerifyClientCert(clientCerts []*x509.Certificate, skipTimeCheck bool) CertOrigin {
	if len(clientCerts) == 0 {
		return CertOriginUntrusted
	}

	self.RLock()
	defer self.RUnlock()

	intermediates := x509.NewCertPool()
	for _, cert := range clientCerts[1:] {
		intermediates.AddCert(cert)
	}

	// Shallow-copy the leaf cert so we can override time fields without mutating the original
	// (which may be shared across concurrent HTTP/2 requests on the same TLS connection).
	leafCopy := *clientCerts[0]
	leaf := &leafCopy
	if skipTimeCheck {
		leaf.NotBefore = time.Now().Add(-1 * time.Hour)
		leaf.NotAfter = time.Now().Add(1 * time.Hour)
	}

	if self.staticFirstPartyRootPool != nil {
		opts := x509.VerifyOptions{
			Roots:         self.staticFirstPartyRootPool,
			Intermediates: intermediates,
			KeyUsages:     []x509.ExtKeyUsage{x509.ExtKeyUsageAny},
		}
		if _, err := leaf.Verify(opts); err == nil {
			return CertOriginFirstParty
		}
	}

	if self.staticFirstPartyTrustAnchorPool != nil {
		opts := x509.VerifyOptions{
			Roots:         self.staticFirstPartyTrustAnchorPool,
			Intermediates: intermediates,
			KeyUsages:     []x509.ExtKeyUsage{x509.ExtKeyUsageAny},
		}
		if _, err := leaf.Verify(opts); err == nil {
			return CertOriginFirstParty
		}
	}

	if self.thirdPartyTrustAnchorPool != nil {
		opts := x509.VerifyOptions{
			Roots:         self.thirdPartyTrustAnchorPool,
			Intermediates: intermediates,
			KeyUsages:     []x509.ExtKeyUsage{x509.ExtKeyUsageAny},
		}
		if _, err := leaf.Verify(opts); err == nil {
			return CertOriginThirdParty
		}
	}

	return CertOriginUntrusted
}

// VerifyClientCertCached is like VerifyClientCert but caches results by fingerprint for the
// configured TTL. Safe because TLS handshake proves private key possession per-connection.
func (self *TrustCache) VerifyClientCertCached(fingerprint string, clientCerts []*x509.Certificate, skipTimeCheck bool) CertOrigin {
	if self.certOriginCache != nil {
		if item := self.certOriginCache.Get(fingerprint); item != nil {
			return item.Value()
		}
	}

	origin := self.VerifyClientCert(clientCerts, skipTimeCheck)

	if self.certOriginCache != nil && origin != CertOriginUntrusted {
		self.certOriginCache.Set(fingerprint, origin, ttlcache.DefaultTTL)
	}

	return origin
}

type CaManager struct {
	baseEntityManager[*Ca, *db.Ca]
	cache TrustCache
}

func (self *CaManager) initCache() {
	self.cache.certOriginCache = ttlcache.New[string, CertOrigin](
		ttlcache.WithTTL[string, CertOrigin](certVerifyCacheTTL),
	)
	go self.cache.certOriginCache.Start()

	err := self.RefreshActiveAuthCaCertCache()
	if err != nil {
		pfxlog.Logger().WithError(err).Info("failed to refresh active auth ca cert cache")
	}
}

func (self *CaManager) GetTrustCache() *TrustCache {
	self.cache.initOnce.Do(self.initCache)
	return &self.cache
}

func (self *CaManager) RefreshActiveAuthCaCertCache() error {
	self.cache.Lock()
	defer self.cache.Unlock()

	// invalidate cached cert verification results since trust pools are changing
	if self.cache.certOriginCache != nil {
		self.cache.certOriginCache.DeleteAll()
	}

	// for TLS config
	allPool := x509.NewCertPool()

	//legacy root + intermediates
	var newStaticFirstPartyTrustAnchors []*x509.Certificate
	newStaticFirstPartyTrustAnchorPool := x509.NewCertPool()

	// ha and forward root only
	var newStaticFirstPartyRoots []*x509.Certificate
	newStaticFirstPartyRootPool := x509.NewCertPool()

	var newThirdPartyTrustAnchors []*x509.Certificate
	newThirdPartyTrustAnchorPool := x509.NewCertPool()

	newActiveThirdPartyCas := map[string]*Ca{}

	for _, cert := range self.env.GetConfig().Edge.CaCerts() {
		//TODO: remove legacy trust anchors (root + intermediate) and use root only
		newStaticFirstPartyTrustAnchors = append(newStaticFirstPartyTrustAnchors, cert)
		newStaticFirstPartyTrustAnchorPool.AddCert(cert)
		allPool.AddCert(cert)

		if identity.IsRootCa(cert) {
			newStaticFirstPartyRoots = append(newStaticFirstPartyRoots, cert)
			newStaticFirstPartyRootPool.AddCert(cert)
		}
	}

	err := self.Stream("isAuthEnabled = true and isVerified = true", func(ca *Ca, err error) error {
		if ca == nil && err == nil {
			return nil
		}

		if err != nil {
			return fmt.Errorf("error refreshing ca cert cache: %v", err)
		}

		caCerts := nfpem.PemStringToCertificates(ca.CertPem)

		if len(caCerts) != 0 {
			newActiveThirdPartyCas[ca.Fingerprint] = ca
			newThirdPartyTrustAnchors = append(newThirdPartyTrustAnchors, caCerts[0])
			newThirdPartyTrustAnchorPool.AddCert(caCerts[0])
			allPool.AddCert(caCerts[0])
		}

		return nil
	})

	self.cache.staticFirstPartyTrustAnchors = newStaticFirstPartyTrustAnchors
	self.cache.staticFirstPartyTrustAnchorPool = newStaticFirstPartyTrustAnchorPool

	self.cache.staticFirstPartyRoots = newStaticFirstPartyRoots
	self.cache.staticFirstPartyRootPool = newStaticFirstPartyRootPool

	self.cache.thirdPartyTrustAnchors = newThirdPartyTrustAnchors
	self.cache.thirdPartyTrustAnchorPool = newThirdPartyTrustAnchorPool
	self.cache.activeThirdPartyCas = newActiveThirdPartyCas

	self.cache.allPool = allPool

	return err
}

func (self *CaManager) NewModelEntity() *Ca {
	return &Ca{}
}

func (self *CaManager) Create(entity *Ca, ctx *change.Context) error {
	return DispatchCreate[*Ca](self, entity, ctx)
}

func (self *CaManager) ApplyCreate(cmd *command.CreateEntityCommand[*Ca], ctx boltz.MutateContext) error {
	_, err := self.createEntity(cmd.Entity, ctx)

	return err
}

func (self *CaManager) Update(entity *Ca, checker fields.UpdatedFields, ctx *change.Context) error {
	if checker != nil {
		checker.RemoveFields(db.FieldCaIsVerified)
	}
	return DispatchUpdate[*Ca](self, entity, checker, ctx)
}

func (self *CaManager) ApplyUpdate(cmd *command.UpdateEntityCommand[*Ca], ctx boltz.MutateContext) error {
	var checker boltz.FieldChecker = self

	// isVerified should only be set by the Verified method. We remove isVerified
	// from updated fields coming through Update method
	if cmd.UpdatedFields != nil {
		if cmd.UpdatedFields.IsUpdated(db.FieldCaIsVerified) {
			checker = cmd.UpdatedFields
		} else {
			checker = &AndFieldChecker{first: self, second: cmd.UpdatedFields}
		}
	}

	return self.updateEntity(cmd.Entity, checker, ctx)
}

func (self *CaManager) Read(id string) (*Ca, error) {
	modelEntity := &Ca{}
	if err := self.readEntity(id, modelEntity); err != nil {
		return nil, err
	}
	return modelEntity, nil
}

func (self *CaManager) readInTx(tx *bbolt.Tx, id string) (*Ca, error) {
	modelEntity := &Ca{}
	if err := self.readEntityInTx(tx, id, modelEntity); err != nil {
		return nil, err
	}
	return modelEntity, nil
}

func (self *CaManager) IsUpdated(field string) bool {
	return strings.EqualFold(field, db.FieldName) ||
		strings.EqualFold(field, boltz.FieldTags) ||
		strings.EqualFold(field, db.FieldCaIsAutoCaEnrollmentEnabled) ||
		strings.EqualFold(field, db.FieldCaIsOttCaEnrollmentEnabled) ||
		strings.EqualFold(field, db.FieldCaIsAuthEnabled) ||
		strings.EqualFold(field, db.FieldIdentityRoles) ||
		strings.EqualFold(field, db.FieldCaIdentityNameFormat) ||
		strings.HasPrefix(field, db.FieldCaExternalIdClaim+".")
}

func (self *CaManager) Verified(ca *Ca, ctx *change.Context) error {
	ca.IsVerified = true
	checker := &fields.UpdatedFieldsMap{
		db.FieldCaIsVerified: struct{}{},
	}
	return DispatchUpdate[*Ca](self, ca, checker, ctx)
}

func (self *CaManager) Query(query string) (*CaListResult, error) {
	result := &CaListResult{manager: self}
	if err := self.ListWithHandler(query, result.collect); err != nil {
		return nil, err
	}
	return result, nil
}

func (self *CaManager) Stream(query string, collect func(*Ca, error) error) error {
	filter, err := ast.Parse(self.Store, query)

	if err != nil {
		return fmt.Errorf("could not parse query for streaming cas: %v", err)
	}

	return self.env.GetDb().View(func(tx *bbolt.Tx) error {
		for cursor := self.Store.IterateIds(tx, filter); cursor.IsValid(); cursor.Next() {
			current := cursor.Current()

			ca, err := self.readInTx(tx, string(current))
			if err := collect(ca, err); err != nil {
				return err
			}
		}
		return collect(nil, nil)
	})
}

func (self *CaManager) Marshall(entity *Ca) ([]byte, error) {
	tags, err := edge_cmd_pb.EncodeTags(entity.Tags)
	if err != nil {
		return nil, err
	}

	var externalIdClaim *edge_cmd_pb.Ca_ExternalIdClaim
	if entity.ExternalIdClaim != nil {
		externalIdClaim = &edge_cmd_pb.Ca_ExternalIdClaim{
			Location:        entity.ExternalIdClaim.Location,
			Matcher:         entity.ExternalIdClaim.Matcher,
			MatcherCriteria: entity.ExternalIdClaim.MatcherCriteria,
			Parser:          entity.ExternalIdClaim.Parser,
			ParserCriteria:  entity.ExternalIdClaim.ParserCriteria,
			Index:           entity.ExternalIdClaim.Index,
		}
	}

	msg := &edge_cmd_pb.Ca{
		Id:                        entity.Id,
		Name:                      entity.Name,
		Tags:                      tags,
		Fingerprint:               entity.Fingerprint,
		CertPem:                   entity.CertPem,
		IsVerified:                entity.IsVerified,
		VerificationToken:         entity.VerificationToken,
		IsAutoCaEnrollmentEnabled: entity.IsAutoCaEnrollmentEnabled,
		IsOttCaEnrollmentEnabled:  entity.IsOttCaEnrollmentEnabled,
		IsAuthEnabled:             entity.IsAuthEnabled,
		IdentityRoles:             entity.IdentityRoles,
		IdentityNameFormat:        entity.IdentityNameFormat,
		ExternalIdClaim:           externalIdClaim,
	}

	return proto.Marshal(msg)
}

func (self *CaManager) Unmarshall(bytes []byte) (*Ca, error) {
	msg := &edge_cmd_pb.Ca{}
	if err := proto.Unmarshal(bytes, msg); err != nil {
		return nil, err
	}

	var externalIdClaim *ExternalIdClaim
	if msg.ExternalIdClaim != nil {
		externalIdClaim = &ExternalIdClaim{
			Location:        msg.ExternalIdClaim.Location,
			Matcher:         msg.ExternalIdClaim.Matcher,
			MatcherCriteria: msg.ExternalIdClaim.MatcherCriteria,
			Parser:          msg.ExternalIdClaim.Parser,
			ParserCriteria:  msg.ExternalIdClaim.ParserCriteria,
			Index:           msg.ExternalIdClaim.Index,
		}
	}

	return &Ca{
		BaseEntity: models.BaseEntity{
			Id:   msg.Id,
			Tags: edge_cmd_pb.DecodeTags(msg.Tags),
		},
		Name:                      msg.Name,
		Fingerprint:               msg.Fingerprint,
		CertPem:                   msg.CertPem,
		IsVerified:                msg.IsVerified,
		VerificationToken:         msg.VerificationToken,
		IsAutoCaEnrollmentEnabled: msg.IsAutoCaEnrollmentEnabled,
		IsOttCaEnrollmentEnabled:  msg.IsOttCaEnrollmentEnabled,
		IsAuthEnabled:             msg.IsAuthEnabled,
		IdentityRoles:             msg.IdentityRoles,
		IdentityNameFormat:        msg.IdentityNameFormat,
		ExternalIdClaim:           externalIdClaim,
	}, nil
}

func (self *CaManager) onMutate(_ *db.Ca) {
	err := self.RefreshActiveAuthCaCertCache()

	if err != nil {
		pfxlog.Logger().WithError(err).Error("error refreshing active auth cas on mutate")
	}
}

type CaListResult struct {
	manager *CaManager
	Cas     []*Ca
	models.QueryMetaData
}

func (result *CaListResult) collect(tx *bbolt.Tx, ids []string, queryMetaData *models.QueryMetaData) error {
	result.QueryMetaData = *queryMetaData
	for _, key := range ids {
		entity, err := result.manager.readInTx(tx, key)
		if err != nil {
			return err
		}
		result.Cas = append(result.Cas, entity)
	}
	return nil
}

const (
	FormatSentinelStart       = "["
	FormatSentinelEnd         = "]"
	FormatSymbolCaName        = "caName"
	FormatSymbolCaId          = "caId"
	FormatSymbolCommonName    = "commonName"
	FormatSymbolRequestedName = "requestedName"
	FormatSymbolIdentityId    = "identityId"

	// DefaultCaIdentityNameFormat = "[caName] - [commonName]"
	DefaultCaIdentityNameFormat = FormatSentinelStart + FormatSymbolCaName + FormatSentinelEnd + "-" + FormatSentinelStart + FormatSymbolCommonName + FormatSentinelEnd
)

type Formatter struct {
	symbolValues  map[string]string
	sentinelStart string
	sentinelEnd   string
}

func NewFormatter(symbols map[string]string) *Formatter {
	return &Formatter{
		symbolValues:  symbols,
		sentinelStart: FormatSentinelStart,
		sentinelEnd:   FormatSentinelEnd,
	}
}

func (formatter *Formatter) Format(name string) string {
	for symbol, value := range formatter.symbolValues {
		searchSymbol := formatter.sentinelStart + symbol + formatter.sentinelEnd
		name = strings.ReplaceAll(name, searchSymbol, value)
	}

	return name
}