open-vault/vault/request_handling.go

534 lines
17 KiB
Go

package vault
import (
"encoding/json"
"fmt"
"strings"
"time"
"github.com/armon/go-metrics"
"github.com/hashicorp/go-multierror"
"github.com/hashicorp/vault/helper/jsonutil"
"github.com/hashicorp/vault/helper/policyutil"
"github.com/hashicorp/vault/helper/strutil"
"github.com/hashicorp/vault/logical"
)
// HandleRequest is used to handle a new incoming request
func (c *Core) HandleRequest(req *logical.Request) (resp *logical.Response, err error) {
c.stateLock.RLock()
defer c.stateLock.RUnlock()
if c.sealed {
return nil, ErrSealed
}
if c.standby {
return nil, ErrStandby
}
// Allowing writing to a path ending in / makes it extremely difficult to
// understand user intent for the filesystem-like backends (generic,
// cubbyhole) -- did they want a key named foo/ or did they want to write
// to a directory foo/ with no (or forgotten) key, or...? It also affects
// lookup, because paths ending in / are considered prefixes by some
// backends. Basically, it's all just terrible, so don't allow it.
if strings.HasSuffix(req.Path, "/") &&
(req.Operation == logical.UpdateOperation ||
req.Operation == logical.CreateOperation) {
return logical.ErrorResponse("cannot write to a path ending in '/'"), nil
}
var auth *logical.Auth
if c.router.LoginPath(req.Path) {
resp, auth, err = c.handleLoginRequest(req)
} else {
resp, auth, err = c.handleRequest(req)
}
// Ensure we don't leak internal data
if resp != nil {
if resp.Secret != nil {
resp.Secret.InternalData = nil
}
if resp.Auth != nil {
resp.Auth.InternalData = nil
}
}
// We are wrapping if there is anything to wrap (not a nil response) and a
// TTL was specified for the token. Errors on a call should be returned to
// the caller, so wrapping is turned off if an error is hit and the error
// is logged to the audit log.
wrapping := resp != nil &&
err == nil &&
!resp.IsError() &&
resp.WrapInfo != nil &&
resp.WrapInfo.TTL != 0
if wrapping {
cubbyResp, cubbyErr := c.wrapInCubbyhole(req, resp)
// If not successful, returns either an error response from the
// cubbyhole backend or an error; if either is set, set resp and err to
// those and continue so that that's what we audit log. Otherwise
// finish the wrapping and audit log that.
if cubbyResp != nil || cubbyErr != nil {
resp = cubbyResp
err = cubbyErr
} else {
wrappingResp := &logical.Response{
WrapInfo: resp.WrapInfo,
}
wrappingResp.CloneWarnings(resp)
resp = wrappingResp
}
}
auditResp := resp
// When unwrapping we want to log the actual response that will be written
// out. We still want to return the raw value to avoid automatic updating
// to any of it.
if req.Path == "sys/wrapping/unwrap" &&
resp != nil &&
resp.Data != nil &&
resp.Data[logical.HTTPRawBody] != nil {
// Decode the JSON
httpResp := &logical.HTTPResponse{}
err := jsonutil.DecodeJSON(resp.Data[logical.HTTPRawBody].([]byte), httpResp)
if err != nil {
c.logger.Error("core: failed to unmarshal wrapped HTTP response for audit logging", "error", err)
return nil, ErrInternalError
}
auditResp = logical.HTTPResponseToLogicalResponse(httpResp)
}
// Create an audit trail of the response
if auditErr := c.auditBroker.LogResponse(auth, req, auditResp, err); auditErr != nil {
c.logger.Error("core: failed to audit response", "request_path", req.Path, "error", auditErr)
return nil, ErrInternalError
}
return
}
func (c *Core) handleRequest(req *logical.Request) (retResp *logical.Response, retAuth *logical.Auth, retErr error) {
defer metrics.MeasureSince([]string{"core", "handle_request"}, time.Now())
// Validate the token
auth, te, ctErr := c.checkToken(req)
// We run this logic first because we want to decrement the use count even in the case of an error
if te != nil {
// Attempt to use the token (decrement NumUses)
var err error
te, err = c.tokenStore.UseToken(te)
if err != nil {
c.logger.Error("core: failed to use token", "error", err)
retErr = multierror.Append(retErr, ErrInternalError)
return nil, nil, retErr
}
if te == nil {
// Token has been revoked by this point
retErr = multierror.Append(retErr, logical.ErrPermissionDenied)
return nil, nil, retErr
}
if te.NumUses == -1 {
// We defer a revocation until after logic has run, since this is a
// valid request (this is the token's final use). We pass the ID in
// directly just to be safe in case something else modifies te later.
defer func(id string) {
err = c.tokenStore.Revoke(id)
if err != nil {
c.logger.Error("core: failed to revoke token", "error", err)
retResp = nil
retAuth = nil
retErr = multierror.Append(retErr, ErrInternalError)
}
if retResp != nil && retResp.Secret != nil &&
// Some backends return a TTL even without a Lease ID
retResp.Secret.LeaseID != "" {
retResp = logical.ErrorResponse("Secret cannot be returned; token had one use left, so leased credentials were immediately revoked.")
return
}
}(te.ID)
}
}
if ctErr != nil {
// If it is an internal error we return that, otherwise we
// return invalid request so that the status codes can be correct
var errType error
switch ctErr {
case ErrInternalError, logical.ErrPermissionDenied:
errType = ctErr
default:
errType = logical.ErrInvalidRequest
}
if err := c.auditBroker.LogRequest(auth, req, ctErr); err != nil {
c.logger.Error("core: failed to audit request", "path", req.Path, "error", err)
}
if errType != nil {
retErr = multierror.Append(retErr, errType)
}
return logical.ErrorResponse(ctErr.Error()), nil, retErr
}
// Attach the display name
req.DisplayName = auth.DisplayName
// Create an audit trail of the request
if err := c.auditBroker.LogRequest(auth, req, nil); err != nil {
c.logger.Error("core: failed to audit request", "path", req.Path, "error", err)
retErr = multierror.Append(retErr, ErrInternalError)
return nil, auth, retErr
}
// Route the request
resp, err := c.router.Route(req)
if resp != nil {
// We don't allow backends to specify this, so ensure it's not set
resp.WrapInfo = nil
if req.WrapTTL != 0 {
resp.WrapInfo = &logical.WrapInfo{
TTL: req.WrapTTL,
}
}
}
// If there is a secret, we must register it with the expiration manager.
// We exclude renewal of a lease, since it does not need to be re-registered
if resp != nil && resp.Secret != nil && !strings.HasPrefix(req.Path, "sys/renew") {
// Get the SystemView for the mount
sysView := c.router.MatchingSystemView(req.Path)
if sysView == nil {
c.logger.Error("core: unable to retrieve system view from router")
retErr = multierror.Append(retErr, ErrInternalError)
return nil, auth, retErr
}
// Apply the default lease if none given
if resp.Secret.TTL == 0 {
resp.Secret.TTL = sysView.DefaultLeaseTTL()
}
// Limit the lease duration
maxTTL := sysView.MaxLeaseTTL()
if resp.Secret.TTL > maxTTL {
resp.Secret.TTL = maxTTL
}
// Generic mounts should return the TTL but not register
// for a lease as this provides a massive slowdown
registerLease := true
matchingBackend := c.router.MatchingBackend(req.Path)
if matchingBackend == nil {
c.logger.Error("core: unable to retrieve generic backend from router")
retErr = multierror.Append(retErr, ErrInternalError)
return nil, auth, retErr
}
if ptbe, ok := matchingBackend.(*PassthroughBackend); ok {
if !ptbe.GeneratesLeases() {
registerLease = false
resp.Secret.Renewable = false
}
}
if registerLease {
leaseID, err := c.expiration.Register(req, resp)
if err != nil {
c.logger.Error("core: failed to register lease", "request_path", req.Path, "error", err)
retErr = multierror.Append(retErr, ErrInternalError)
return nil, auth, retErr
}
resp.Secret.LeaseID = leaseID
}
}
// Only the token store is allowed to return an auth block, for any
// other request this is an internal error. We exclude renewal of a token,
// since it does not need to be re-registered
if resp != nil && resp.Auth != nil && !strings.HasPrefix(req.Path, "auth/token/renew") {
if !strings.HasPrefix(req.Path, "auth/token/") {
c.logger.Error("core: unexpected Auth response for non-token backend", "request_path", req.Path)
retErr = multierror.Append(retErr, ErrInternalError)
return nil, auth, retErr
}
// Register with the expiration manager. We use the token's actual path
// here because roles allow suffixes.
te, err := c.tokenStore.Lookup(resp.Auth.ClientToken)
if err != nil {
c.logger.Error("core: failed to look up token", "error", err)
retErr = multierror.Append(retErr, ErrInternalError)
return nil, nil, retErr
}
if err := c.expiration.RegisterAuth(te.Path, resp.Auth); err != nil {
c.logger.Error("core: failed to register token lease", "request_path", req.Path, "error", err)
retErr = multierror.Append(retErr, ErrInternalError)
return nil, auth, retErr
}
}
if resp != nil &&
req.Path == "cubbyhole/response" &&
len(te.Policies) == 1 &&
te.Policies[0] == responseWrappingPolicyName {
resp.AddWarning("Reading from 'cubbyhole/response' is deprecated. Please use sys/wrapping/unwrap to unwrap responses, as it provides additional security checks and other benefits.")
}
// Return the response and error
if err != nil {
retErr = multierror.Append(retErr, err)
}
return resp, auth, retErr
}
// handleLoginRequest is used to handle a login request, which is an
// unauthenticated request to the backend.
func (c *Core) handleLoginRequest(req *logical.Request) (*logical.Response, *logical.Auth, error) {
defer metrics.MeasureSince([]string{"core", "handle_login_request"}, time.Now())
// Create an audit trail of the request, auth is not available on login requests
if err := c.auditBroker.LogRequest(nil, req, nil); err != nil {
c.logger.Error("core: failed to audit request", "path", req.Path, "error", err)
return nil, nil, ErrInternalError
}
// The token store uses authentication even when creating a new token,
// so it's handled in handleRequest. It should not be reached here.
if strings.HasPrefix(req.Path, "auth/token/") {
c.logger.Error("core: unexpected login request for token backend", "request_path", req.Path)
return nil, nil, ErrInternalError
}
// Route the request
resp, err := c.router.Route(req)
if resp != nil {
// We don't allow backends to specify this, so ensure it's not set
resp.WrapInfo = nil
if req.WrapTTL != 0 {
resp.WrapInfo = &logical.WrapInfo{
TTL: req.WrapTTL,
}
}
}
// A login request should never return a secret!
if resp != nil && resp.Secret != nil {
c.logger.Error("core: unexpected Secret response for login path", "request_path", req.Path)
return nil, nil, ErrInternalError
}
// If the response generated an authentication, then generate the token
var auth *logical.Auth
if resp != nil && resp.Auth != nil {
auth = resp.Auth
if strutil.StrListSubset(auth.Policies, []string{"root"}) {
return logical.ErrorResponse("authentication backends cannot create root tokens"), nil, logical.ErrInvalidRequest
}
// Determine the source of the login
source := c.router.MatchingMount(req.Path)
source = strings.TrimPrefix(source, credentialRoutePrefix)
source = strings.Replace(source, "/", "-", -1)
// Prepend the source to the display name
auth.DisplayName = strings.TrimSuffix(source+auth.DisplayName, "-")
sysView := c.router.MatchingSystemView(req.Path)
if sysView == nil {
c.logger.Error("core: unable to look up sys view for login path", "request_path", req.Path)
return nil, nil, ErrInternalError
}
// Set the default lease if not provided
if auth.TTL == 0 {
auth.TTL = sysView.DefaultLeaseTTL()
}
// Limit the lease duration
if auth.TTL > sysView.MaxLeaseTTL() {
auth.TTL = sysView.MaxLeaseTTL()
}
// Generate a token
te := TokenEntry{
Path: req.Path,
Policies: auth.Policies,
Meta: auth.Metadata,
DisplayName: auth.DisplayName,
CreationTime: time.Now().Unix(),
TTL: auth.TTL,
}
te.Policies = policyutil.SanitizePolicies(te.Policies, true)
// Prevent internal policies from being assigned to tokens
for _, policy := range te.Policies {
if strutil.StrListContains(nonAssignablePolicies, policy) {
return logical.ErrorResponse(fmt.Sprintf("cannot assign policy %q", policy)), nil, logical.ErrInvalidRequest
}
}
if err := c.tokenStore.create(&te); err != nil {
c.logger.Error("core: failed to create token", "error", err)
return nil, auth, ErrInternalError
}
// Populate the client token and accessor
auth.ClientToken = te.ID
auth.Accessor = te.Accessor
auth.Policies = te.Policies
// Register with the expiration manager
if err := c.expiration.RegisterAuth(te.Path, auth); err != nil {
c.logger.Error("core: failed to register token lease", "request_path", req.Path, "error", err)
return nil, auth, ErrInternalError
}
// Attach the display name, might be used by audit backends
req.DisplayName = auth.DisplayName
}
return resp, auth, err
}
func (c *Core) wrapInCubbyhole(req *logical.Request, resp *logical.Response) (*logical.Response, error) {
// Before wrapping, obey special rules for listing: if no entries are
// found, 404. This prevents unwrapping only to find empty data.
if req.Operation == logical.ListOperation {
if resp == nil || len(resp.Data) == 0 {
return nil, logical.ErrUnsupportedPath
}
keysRaw, ok := resp.Data["keys"]
if !ok || keysRaw == nil {
return nil, logical.ErrUnsupportedPath
}
keys, ok := keysRaw.([]string)
if !ok {
return nil, logical.ErrUnsupportedPath
}
if len(keys) == 0 {
return nil, logical.ErrUnsupportedPath
}
}
// If we are wrapping, the first part (performed in this functions) happens
// before auditing so that resp.WrapInfo.Token can contain the HMAC'd
// wrapping token ID in the audit logs, so that it can be determined from
// the audit logs whether the token was ever actually used.
creationTime := time.Now()
te := TokenEntry{
Path: req.Path,
Policies: []string{"response-wrapping"},
CreationTime: creationTime.Unix(),
TTL: resp.WrapInfo.TTL,
NumUses: 1,
ExplicitMaxTTL: resp.WrapInfo.TTL,
}
if err := c.tokenStore.create(&te); err != nil {
c.logger.Error("core: failed to create wrapping token", "error", err)
return nil, ErrInternalError
}
resp.WrapInfo.Token = te.ID
resp.WrapInfo.CreationTime = creationTime
// This will only be non-nil if this response contains a token, so in that
// case put the accessor in the wrap info.
if resp.Auth != nil {
resp.WrapInfo.WrappedAccessor = resp.Auth.Accessor
}
cubbyReq := &logical.Request{
Operation: logical.CreateOperation,
Path: "cubbyhole/response",
ClientToken: te.ID,
}
// During a rewrap, store the original response, don't wrap it again.
if req.Path == "sys/wrapping/rewrap" {
cubbyReq.Data = map[string]interface{}{
"response": resp.Data["response"],
}
} else {
httpResponse := logical.LogicalResponseToHTTPResponse(resp)
// Add the unique identifier of the original request to the response
httpResponse.RequestID = req.ID
// Because of the way that JSON encodes (likely just in Go) we actually get
// mixed-up values for ints if we simply put this object in the response
// and encode the whole thing; so instead we marshal it first, then store
// the string response. This actually ends up making it easier on the
// client side, too, as it becomes a straight read-string-pass-to-unmarshal
// operation.
marshaledResponse, err := json.Marshal(httpResponse)
if err != nil {
c.logger.Error("core: failed to marshal wrapped response", "error", err)
return nil, ErrInternalError
}
cubbyReq.Data = map[string]interface{}{
"response": string(marshaledResponse),
}
}
cubbyResp, err := c.router.Route(cubbyReq)
if err != nil {
// Revoke since it's not yet being tracked for expiration
c.tokenStore.Revoke(te.ID)
c.logger.Error("core: failed to store wrapped response information", "error", err)
return nil, ErrInternalError
}
if cubbyResp != nil && cubbyResp.IsError() {
c.tokenStore.Revoke(te.ID)
c.logger.Error("core: failed to store wrapped response information", "error", cubbyResp.Data["error"])
return cubbyResp, nil
}
// Store info for lookup
cubbyReq.Path = "cubbyhole/wrapinfo"
cubbyReq.Data = map[string]interface{}{
"creation_ttl": resp.WrapInfo.TTL,
"creation_time": creationTime,
}
cubbyResp, err = c.router.Route(cubbyReq)
if err != nil {
// Revoke since it's not yet being tracked for expiration
c.tokenStore.Revoke(te.ID)
c.logger.Error("core: failed to store wrapping information", "error", err)
return nil, ErrInternalError
}
if cubbyResp != nil && cubbyResp.IsError() {
c.tokenStore.Revoke(te.ID)
c.logger.Error("core: failed to store wrapping information", "error", cubbyResp.Data["error"])
return cubbyResp, nil
}
auth := &logical.Auth{
ClientToken: te.ID,
Policies: []string{"response-wrapping"},
LeaseOptions: logical.LeaseOptions{
TTL: te.TTL,
Renewable: false,
},
}
// Register the wrapped token with the expiration manager
if err := c.expiration.RegisterAuth(te.Path, auth); err != nil {
// Revoke since it's not yet being tracked for expiration
c.tokenStore.Revoke(te.ID)
c.logger.Error("core: failed to register cubbyhole wrapping token lease", "request_path", req.Path, "error", err)
return nil, ErrInternalError
}
return nil, nil
}