open-consul/agent/connect/ca/provider_vault.go

1033 lines
33 KiB
Go

package ca
import (
"bytes"
"context"
"crypto/x509"
"encoding/pem"
"fmt"
"io"
"net/http"
"os"
"strings"
"sync"
"time"
"github.com/hashicorp/go-hclog"
vaultapi "github.com/hashicorp/vault/api"
"github.com/mitchellh/mapstructure"
"github.com/hashicorp/consul/agent/connect"
"github.com/hashicorp/consul/agent/structs"
"github.com/hashicorp/consul/lib"
"github.com/hashicorp/consul/lib/decode"
"github.com/hashicorp/consul/lib/retry"
)
const (
VaultCALeafCertRole = "leaf-cert"
VaultAuthMethodTypeAliCloud = "alicloud"
VaultAuthMethodTypeAppRole = "approle"
VaultAuthMethodTypeAWS = "aws"
VaultAuthMethodTypeAzure = "azure"
VaultAuthMethodTypeCloudFoundry = "cf"
VaultAuthMethodTypeGitHub = "github"
VaultAuthMethodTypeGCP = "gcp"
VaultAuthMethodTypeJWT = "jwt"
VaultAuthMethodTypeKerberos = "kerberos"
VaultAuthMethodTypeKubernetes = "kubernetes"
VaultAuthMethodTypeLDAP = "ldap"
VaultAuthMethodTypeOCI = "oci"
VaultAuthMethodTypeOkta = "okta"
VaultAuthMethodTypeRadius = "radius"
VaultAuthMethodTypeTLS = "cert"
VaultAuthMethodTypeToken = "token"
VaultAuthMethodTypeUserpass = "userpass"
defaultK8SServiceAccountTokenPath = "/var/run/secrets/kubernetes.io/serviceaccount/token"
retryMin = 1 * time.Second
retryMax = 5 * time.Second
retryJitter = 20
)
var ErrBackendNotMounted = fmt.Errorf("backend not mounted")
var ErrBackendNotInitialized = fmt.Errorf("backend not initialized")
type VaultProvider struct {
config *structs.VaultCAProviderConfig
client *vaultapi.Client
// We modify the namespace on the fly to override default namespace for rootCertificate and intermediateCertificate. Can't guarantee
// all operations (specifically Sign) are not called re-entrantly, so we add this for safety.
clientMutex sync.Mutex
baseNamespace string
stopWatcher func()
isPrimary bool
clusterID string
spiffeID *connect.SpiffeIDSigning
logger hclog.Logger
// isConsulMountedIntermediate is used to determine if we should tune the
// mount if the VaultProvider is ever reconfigured. This is at most a
// "best guess" to determine whether this instance of Consul created the
// intermediate mount but will not be able to tell if an existing mount
// was created by Consul (in a previous running instance) or was external.
isConsulMountedIntermediate bool
}
var _ Provider = (*VaultProvider)(nil)
func NewVaultProvider(logger hclog.Logger) *VaultProvider {
return &VaultProvider{
stopWatcher: func() {},
logger: logger,
}
}
func vaultTLSConfig(config *structs.VaultCAProviderConfig) *vaultapi.TLSConfig {
return &vaultapi.TLSConfig{
CACert: config.CAFile,
CAPath: config.CAPath,
ClientCert: config.CertFile,
ClientKey: config.KeyFile,
Insecure: config.TLSSkipVerify,
TLSServerName: config.TLSServerName,
}
}
// Configure sets up the provider using the given configuration.
func (v *VaultProvider) Configure(cfg ProviderConfig) error {
config, err := ParseVaultCAConfig(cfg.RawConfig)
if err != nil {
return err
}
clientConf := &vaultapi.Config{
Address: config.Address,
}
err = clientConf.ConfigureTLS(vaultTLSConfig(config))
if err != nil {
return err
}
client, err := vaultapi.NewClient(clientConf)
if err != nil {
return err
}
// We don't want to set the namespace if it's empty to prevent potential
// unknown behavior (what does Vault do with an empty namespace). The Vault
// client also makes sure the inputs are not empty strings so let's do the
// same.
if config.Namespace != "" {
client.SetNamespace(config.Namespace)
v.baseNamespace = config.Namespace
}
if config.AuthMethod != nil {
loginResp, err := vaultLogin(client, config.AuthMethod)
if err != nil {
return err
}
config.Token = loginResp.Auth.ClientToken
}
client.SetToken(config.Token)
v.config = config
v.client = client
v.isPrimary = cfg.IsPrimary
v.clusterID = cfg.ClusterID
v.spiffeID = connect.SpiffeIDSigningForCluster(v.clusterID)
// Look up the token to see if we can auto-renew its lease.
secret, err := client.Auth().Token().LookupSelf()
if err != nil {
return err
} else if secret == nil {
return fmt.Errorf("could not look up Vault provider token: not found")
}
var token struct {
Renewable bool
TTL int
}
if err := mapstructure.Decode(secret.Data, &token); err != nil {
return err
}
// Set up a renewer to renew the token automatically, if supported.
if token.Renewable || config.AuthMethod != nil {
lifetimeWatcher, err := client.NewLifetimeWatcher(&vaultapi.LifetimeWatcherInput{
Secret: &vaultapi.Secret{
Auth: &vaultapi.SecretAuth{
ClientToken: config.Token,
Renewable: token.Renewable,
LeaseDuration: secret.LeaseDuration,
},
},
Increment: token.TTL,
RenewBehavior: vaultapi.RenewBehaviorIgnoreErrors,
})
if err != nil {
return fmt.Errorf("error beginning Vault provider token renewal: %v", err)
}
ctx, cancel := context.WithCancel(context.Background())
if v.stopWatcher != nil {
v.stopWatcher()
}
v.stopWatcher = cancel
go v.renewToken(ctx, lifetimeWatcher)
}
// Update the intermediate (managed) PKI mount and role
if err := v.setupIntermediatePKIPath(); err != nil {
return err
}
return nil
}
func (v *VaultProvider) ValidateConfigUpdate(prevRaw, nextRaw map[string]interface{}) error {
prev, err := ParseVaultCAConfig(prevRaw)
if err != nil {
return fmt.Errorf("failed to parse existing CA config: %w", err)
}
next, err := ParseVaultCAConfig(nextRaw)
if err != nil {
return fmt.Errorf("failed to parse new CA config: %w", err)
}
if prev.RootPKIPath != next.RootPKIPath {
return nil
}
if prev.PrivateKeyType != "" && prev.PrivateKeyType != connect.DefaultPrivateKeyType {
if prev.PrivateKeyType != next.PrivateKeyType {
return fmt.Errorf("cannot update the PrivateKeyType field without changing RootPKIPath")
}
}
if prev.PrivateKeyBits != 0 && prev.PrivateKeyBits != connect.DefaultPrivateKeyBits {
if prev.PrivateKeyBits != next.PrivateKeyBits {
return fmt.Errorf("cannot update the PrivateKeyBits field without changing RootPKIPath")
}
}
return nil
}
// renewToken uses a vaultapi.LifetimeWatcher to repeatedly renew our token's lease.
// If the token can no longer be renewed and auth method is set,
// it will re-authenticate to Vault using the auth method and restart the renewer with the new token.
func (v *VaultProvider) renewToken(ctx context.Context, watcher *vaultapi.LifetimeWatcher) {
go watcher.Start()
defer watcher.Stop()
// TODO: Once we've upgraded to a later version of protobuf we can upgrade to github.com/hashicorp/vault/api@1.1.1
// or later and rip this out.
retrier := retry.Waiter{
MinFailures: 5,
MinWait: retryMin,
MaxWait: retryMax,
Jitter: retry.NewJitter(retryJitter),
}
for {
select {
case <-ctx.Done():
return
case err := <-watcher.DoneCh():
// In the event we fail to login to Vault or our token is no longer valid we can overwhelm a Vault instance
// with rate limit configured. We would make these requests to Vault as fast as we possibly could and start
// causing all client's to receive 429 response codes. To mitigate that we're sleeping 1 second or less
// before moving on to login again and restart the lifetime watcher. Once we can upgrade to
// github.com/hashicorp/vault/api@v1.1.1 or later the LifetimeWatcher _should_ perform that backoff for us.
if err != nil {
v.logger.Error("Error renewing token for Vault provider", "error", err)
}
// wait at least 1 second after returning from the lifetime watcher
retrier.Wait(ctx)
// If the watcher has exited and auth method is enabled,
// re-authenticate using the auth method and set up a new watcher.
if v.config.AuthMethod != nil {
// Login to Vault using the auth method.
loginResp, err := vaultLogin(v.client, v.config.AuthMethod)
if err != nil {
v.logger.Error("Error login in to Vault with %q auth method", v.config.AuthMethod.Type)
// Restart the watcher
go watcher.Start()
continue
}
// Set the new token for the vault client.
v.client.SetToken(loginResp.Auth.ClientToken)
v.logger.Info("Successfully re-authenticated with Vault using auth method")
// Start the new watcher for the new token.
watcher, err = v.client.NewLifetimeWatcher(&vaultapi.LifetimeWatcherInput{
Secret: loginResp,
RenewBehavior: vaultapi.RenewBehaviorIgnoreErrors,
})
if err != nil {
v.logger.Error("Error starting token renewal process")
go watcher.Start()
continue
}
}
// Restart the watcher.
go watcher.Start()
case <-watcher.RenewCh():
retrier.Reset()
v.logger.Info("Successfully renewed token for Vault provider")
}
}
}
// State implements Provider. Vault provider needs no state other than the
// user-provided config currently.
func (v *VaultProvider) State() (map[string]string, error) {
return nil, nil
}
// GenerateRoot mounts and initializes a new root PKI backend if needed.
func (v *VaultProvider) GenerateRoot() (RootResult, error) {
if !v.isPrimary {
return RootResult{}, fmt.Errorf("provider is not the root certificate authority")
}
// Set up the root PKI backend if necessary.
rootPEM, err := v.getCA(v.config.RootPKINamespace, v.config.RootPKIPath)
switch err {
case ErrBackendNotMounted:
err := v.mountNamespaced(v.config.RootPKINamespace, v.config.RootPKIPath, &vaultapi.MountInput{
Type: "pki",
Description: "root CA backend for Consul Connect",
Config: vaultapi.MountConfigInput{
// the max lease ttl denotes the maximum ttl that secrets are created from the engine
// the default lease ttl is the kind of ttl that will *reliably* set the ttl to v.config.RootCertTTL
// https://www.vaultproject.io/docs/secrets/pki#configure-a-ca-certificate
MaxLeaseTTL: v.config.RootCertTTL.String(),
DefaultLeaseTTL: v.config.RootCertTTL.String(),
},
})
if err != nil {
return RootResult{}, fmt.Errorf("failed to mount root CA backend: %w", err)
}
// We want to initialize afterwards
fallthrough
case ErrBackendNotInitialized:
uid, err := connect.CompactUID()
if err != nil {
return RootResult{}, err
}
resp, err := v.writeNamespaced(v.config.RootPKINamespace, v.config.RootPKIPath+"root/generate/internal", map[string]interface{}{
"common_name": connect.CACN("vault", uid, v.clusterID, v.isPrimary),
"uri_sans": v.spiffeID.URI().String(),
"key_type": v.config.PrivateKeyType,
"key_bits": v.config.PrivateKeyBits,
})
if err != nil {
return RootResult{}, fmt.Errorf("failed to initialize root CA: %w", err)
}
var ok bool
rootPEM, ok = resp.Data["certificate"].(string)
if !ok {
return RootResult{}, fmt.Errorf("unexpected response from Vault: %v", resp.Data["certificate"])
}
default:
if err != nil {
return RootResult{}, fmt.Errorf("unexpected error while setting root PKI backend: %w", err)
}
}
rootChain, err := v.getCAChain(v.config.RootPKINamespace, v.config.RootPKIPath)
if err != nil {
return RootResult{}, err
}
// Workaround for a bug in the Vault PKI API.
// See https://github.com/hashicorp/vault/issues/13489
if rootChain == "" {
rootChain = rootPEM
}
return RootResult{PEM: rootChain}, nil
}
// GenerateIntermediateCSR creates a private key and generates a CSR
// for another datacenter's root to sign, overwriting the intermediate backend
// in the process.
func (v *VaultProvider) GenerateIntermediateCSR() (string, string, error) {
if v.isPrimary {
return "", "", fmt.Errorf("provider is the root certificate authority, " +
"cannot generate an intermediate CSR")
}
return v.generateIntermediateCSR()
}
func (v *VaultProvider) setupIntermediatePKIPath() error {
mountConfig := vaultapi.MountConfigInput{
MaxLeaseTTL: v.config.IntermediateCertTTL.String(),
}
_, err := v.getCA(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath)
if err != nil {
if err == ErrBackendNotMounted {
err := v.mountNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath, &vaultapi.MountInput{
Type: "pki",
Description: "intermediate CA backend for Consul Connect",
Config: mountConfig,
})
if err != nil {
return fmt.Errorf("failed to mount intermediate PKI backend: %w", err)
}
// Required to determine if we should tune the mount
// if the VaultProvider is ever reconfigured.
v.isConsulMountedIntermediate = true
} else if err == ErrBackendNotInitialized {
// If this is the first time calling setupIntermediatePKIPath, the backend
// will not have been initialized. Since the mount is ready we can suppress
// this error.
} else {
return fmt.Errorf("unexpected error while fetching intermediate CA: %w", err)
}
} else {
v.logger.Info("Found existing Intermediate PKI path mount",
"namespace", v.config.IntermediatePKINamespace,
"path", v.config.IntermediatePKIPath,
)
// This codepath requires the Vault policy:
//
// path "/sys/mounts/<intermediate_pki_path>/tune" {
// capabilities = [ "update" ]
// }
//
err := v.tuneMountNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath, &mountConfig)
if err != nil {
if v.isConsulMountedIntermediate {
v.logger.Warn("Intermediate PKI path was mounted by Consul but could not be tuned",
"namespace", v.config.IntermediatePKINamespace,
"path", v.config.IntermediatePKIPath,
"error", err,
)
} else {
v.logger.Debug("Failed to tune Intermediate PKI mount. 403 Forbidden is expected if Consul does not have tune capabilities for the Intermediate PKI mount (i.e. using Vault-managed policies)",
"namespace", v.config.IntermediatePKINamespace,
"path", v.config.IntermediatePKIPath,
"error", err,
)
}
}
}
// Create the role for issuing leaf certs
rolePath := v.config.IntermediatePKIPath + "roles/" + VaultCALeafCertRole
_, err = v.writeNamespaced(v.config.IntermediatePKINamespace, rolePath, map[string]interface{}{
"allow_any_name": true,
"allowed_uri_sans": "spiffe://*",
"key_type": "any",
"max_ttl": v.config.LeafCertTTL.String(),
"no_store": true,
"require_cn": false,
})
return err
}
// generateIntermediateCSR returns the CSR and key_id (only present in
// Vault 1.11+) or any errors encountered.
func (v *VaultProvider) generateIntermediateCSR() (string, string, error) {
// Generate a new intermediate CSR for the root to sign.
uid, err := connect.CompactUID()
if err != nil {
return "", "", err
}
data, err := v.writeNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath+"intermediate/generate/internal", map[string]interface{}{
"common_name": connect.CACN("vault", uid, v.clusterID, v.isPrimary),
"key_type": v.config.PrivateKeyType,
"key_bits": v.config.PrivateKeyBits,
"uri_sans": v.spiffeID.URI().String(),
})
if err != nil {
return "", "", err
}
if data == nil || data.Data["csr"] == "" {
return "", "", fmt.Errorf("got empty value when generating intermediate CSR")
}
csr, ok := data.Data["csr"].(string)
if !ok {
return "", "", fmt.Errorf("csr result is not a string")
}
// Vault 1.11+ will return a "key_id" field which helps
// identify the correct issuer to set as default.
// https://github.com/hashicorp/vault/blob/e445c8b4f58dc20a0316a7fd1b5725b401c3b17a/builtin/logical/pki/path_intermediate.go#L154
if rawkeyId, ok := data.Data["key_id"]; ok {
keyId, ok := rawkeyId.(string)
if !ok {
return "", "", fmt.Errorf("key_id is not a string")
}
return csr, keyId, nil
}
return csr, "", nil
}
// SetIntermediate writes the incoming intermediate and root certificates to the
// intermediate backend (as a chain).
func (v *VaultProvider) SetIntermediate(intermediatePEM, rootPEM, keyId string) error {
if v.isPrimary {
return fmt.Errorf("cannot set an intermediate using another root in the primary datacenter")
}
err := validateSetIntermediate(intermediatePEM, rootPEM, v.spiffeID)
if err != nil {
return err
}
importResp, err := v.writeNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath+"intermediate/set-signed", map[string]interface{}{
"certificate": intermediatePEM,
})
if err != nil {
return err
}
// Vault 1.11+ will return a non-nil response from intermediate/set-signed
if importResp != nil {
err := v.setDefaultIntermediateIssuer(importResp, keyId)
if err != nil {
return fmt.Errorf("failed to update default intermediate issuer: %w", err)
}
}
return nil
}
// ActiveIntermediate returns the current intermediate certificate.
func (v *VaultProvider) ActiveIntermediate() (string, error) {
cert, err := v.getCA(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath)
// This error is expected when calling initializeSecondaryCA for the
// first time. It means that the backend is mounted and ready, but
// there is no intermediate.
// This error is swallowed because there is nothing the caller can do
// about it. The caller needs to handle the empty cert though and
// create an intermediate CA.
if err == ErrBackendNotInitialized {
return "", nil
}
return cert, err
}
// getCA returns the raw CA cert for the given endpoint if there is one.
// We have to use the raw NewRequest call here instead of Logical().Read
// because the endpoint only returns the raw PEM contents of the CA cert
// and not the typical format of the secrets endpoints.
func (v *VaultProvider) getCA(namespace, path string) (string, error) {
defer v.setNamespace(namespace)()
req := v.client.NewRequest("GET", "/v1/"+path+"/ca/pem")
resp, err := v.client.RawRequest(req)
if resp != nil {
defer resp.Body.Close()
}
if resp != nil && resp.StatusCode == http.StatusNotFound {
return "", ErrBackendNotMounted
}
if err != nil {
return "", err
}
bytes, err := io.ReadAll(resp.Body)
if err != nil {
return "", err
}
root := lib.EnsureTrailingNewline(string(bytes))
if root == "" {
return "", ErrBackendNotInitialized
}
return root, nil
}
// TODO: refactor to remove duplication with getCA
func (v *VaultProvider) getCAChain(namespace, path string) (string, error) {
defer v.setNamespace(namespace)()
req := v.client.NewRequest("GET", "/v1/"+path+"/ca_chain")
resp, err := v.client.RawRequest(req)
if resp != nil {
defer resp.Body.Close()
}
if resp != nil && resp.StatusCode == http.StatusNotFound {
return "", ErrBackendNotMounted
}
if err != nil {
return "", err
}
raw, err := io.ReadAll(resp.Body)
if err != nil {
return "", err
}
root := lib.EnsureTrailingNewline(string(raw))
return root, nil
}
// GenerateIntermediate mounts the configured intermediate PKI backend if
// necessary, then generates and signs a new CA CSR using the root PKI backend
// and updates the intermediate backend to use that new certificate.
func (v *VaultProvider) GenerateIntermediate() (string, error) {
csr, keyId, err := v.generateIntermediateCSR()
if err != nil {
return "", err
}
// Sign the CSR with the root backend.
intermediate, err := v.writeNamespaced(v.config.RootPKINamespace, v.config.RootPKIPath+"root/sign-intermediate", map[string]interface{}{
"csr": csr,
"use_csr_values": true,
"format": "pem_bundle",
"ttl": v.config.IntermediateCertTTL.String(),
})
if err != nil {
return "", err
}
if intermediate == nil || intermediate.Data["certificate"] == "" {
return "", fmt.Errorf("got empty value when generating intermediate certificate")
}
// Set the intermediate backend to use the new certificate.
importResp, err := v.writeNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath+"intermediate/set-signed", map[string]interface{}{
"certificate": intermediate.Data["certificate"],
})
if err != nil {
return "", err
}
// Vault 1.11+ will return a non-nil response from intermediate/set-signed
if importResp != nil {
err := v.setDefaultIntermediateIssuer(importResp, keyId)
if err != nil {
return "", fmt.Errorf("failed to update default intermediate issuer: %w", err)
}
}
return v.ActiveIntermediate()
}
// setDefaultIntermediateIssuer updates the default issuer for
// intermediate CA since Vault, as part of its 1.11+ support for
// multiple issuers, no longer overwrites the default issuer when
// generateIntermediateCSR (intermediate/generate/internal) is called.
//
// The response we get from calling [/intermediate/set-signed]
// should contain a "mapping" data field we can use to cross-reference
// with the keyId returned when calling [/intermediate/generate/internal].
//
// [/intermediate/set-signed]: https://developer.hashicorp.com/vault/api-docs/secret/pki#import-ca-certificates-and-keys
// [/intermediate/generate/internal]: https://developer.hashicorp.com/vault/api-docs/secret/pki#generate-intermediate-csr
func (v *VaultProvider) setDefaultIntermediateIssuer(vaultResp *vaultapi.Secret, keyId string) error {
if vaultResp.Data["mapping"] == nil {
return fmt.Errorf("expected Vault response data to have a 'mapping' key")
}
if keyId == "" {
return fmt.Errorf("expected non-empty keyId")
}
mapping, ok := vaultResp.Data["mapping"].(map[string]any)
if !ok {
return fmt.Errorf("unexpected type for 'mapping' value in Vault response")
}
var intermediateId string
// The value in this KV pair is called "key"
for issuer, key := range mapping {
if key == keyId {
// Expect to find the key_id we got from Vault when we
// generated the intermediate CSR.
intermediateId = issuer
break
}
}
if intermediateId == "" {
return fmt.Errorf("could not find key_id %q in response from vault", keyId)
}
// For Vault 1.11+ it is important to GET then POST to avoid clobbering fields
// like `default_follows_latest_issuer`.
// https://developer.hashicorp.com/vault/api-docs/secret/pki#default_follows_latest_issuer
resp, err := v.readNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath+"config/issuers")
if err != nil {
return fmt.Errorf("could not read from /config/issuers: %w", err)
}
issuersConf := resp.Data
// Overwrite the default issuer
issuersConf["default"] = intermediateId
_, err = v.writeNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath+"config/issuers", issuersConf)
if err != nil {
return fmt.Errorf("could not write default issuer to /config/issuers: %w", err)
}
return nil
}
// Sign calls the configured role in the intermediate PKI backend to issue
// a new leaf certificate based on the provided CSR, with the issuing
// intermediate CA cert attached.
func (v *VaultProvider) Sign(csr *x509.CertificateRequest) (string, error) {
connect.HackSANExtensionForCSR(csr)
var pemBuf bytes.Buffer
if err := pem.Encode(&pemBuf, &pem.Block{Type: "CERTIFICATE REQUEST", Bytes: csr.Raw}); err != nil {
return "", err
}
// Use the leaf cert role to sign a new cert for this CSR.
response, err := v.writeNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath+"sign/"+VaultCALeafCertRole, map[string]interface{}{
"csr": pemBuf.String(),
"ttl": v.config.LeafCertTTL.String(),
})
if err != nil {
return "", fmt.Errorf("error issuing cert: %v", err)
}
if response == nil || response.Data["certificate"] == "" || response.Data["issuing_ca"] == "" {
return "", fmt.Errorf("certificate info returned from Vault was blank")
}
cert, ok := response.Data["certificate"].(string)
if !ok {
return "", fmt.Errorf("certificate was not a string")
}
return lib.EnsureTrailingNewline(cert), nil
}
// SignIntermediate returns a signed CA certificate with a path length constraint
// of 0 to ensure that the certificate cannot be used to generate further CA certs.
func (v *VaultProvider) SignIntermediate(csr *x509.CertificateRequest) (string, error) {
err := validateSignIntermediate(csr, v.spiffeID)
if err != nil {
return "", err
}
var pemBuf bytes.Buffer
err = pem.Encode(&pemBuf, &pem.Block{Type: "CERTIFICATE REQUEST", Bytes: csr.Raw})
if err != nil {
return "", err
}
// Sign the CSR with the root backend.
data, err := v.writeNamespaced(v.config.RootPKINamespace, v.config.RootPKIPath+"root/sign-intermediate", map[string]interface{}{
"csr": pemBuf.String(),
"use_csr_values": true,
"format": "pem_bundle",
"max_path_length": 0,
"ttl": v.config.IntermediateCertTTL.String(),
})
if err != nil {
return "", err
}
if data == nil || data.Data["certificate"] == "" {
return "", fmt.Errorf("got empty value when generating intermediate certificate")
}
intermediate, ok := data.Data["certificate"].(string)
if !ok {
return "", fmt.Errorf("signed intermediate result is not a string")
}
return lib.EnsureTrailingNewline(intermediate), nil
}
// CrossSignCA takes a CA certificate and cross-signs it to form a trust chain
// back to our active root.
func (v *VaultProvider) CrossSignCA(cert *x509.Certificate) (string, error) {
rootPEM, err := v.getCA(v.config.RootPKINamespace, v.config.RootPKIPath)
if err != nil {
return "", fmt.Errorf("failed to get root CA: %w", err)
}
rootCert, err := connect.ParseCert(rootPEM)
if err != nil {
return "", fmt.Errorf("error parsing root cert: %v", err)
}
if rootCert.NotAfter.Before(time.Now()) {
return "", fmt.Errorf("root certificate is expired")
}
var pemBuf bytes.Buffer
err = pem.Encode(&pemBuf, &pem.Block{Type: "CERTIFICATE", Bytes: cert.Raw})
if err != nil {
return "", err
}
// Have the root PKI backend sign this cert.
response, err := v.writeNamespaced(v.config.RootPKINamespace, v.config.RootPKIPath+"root/sign-self-issued", map[string]interface{}{
"certificate": pemBuf.String(),
})
if err != nil {
return "", fmt.Errorf("error having Vault cross-sign cert: %v", err)
}
if response == nil || response.Data["certificate"] == "" {
return "", fmt.Errorf("certificate info returned from Vault was blank")
}
xcCert, ok := response.Data["certificate"].(string)
if !ok {
return "", fmt.Errorf("certificate was not a string")
}
return lib.EnsureTrailingNewline(xcCert), nil
}
// SupportsCrossSigning implements Provider
func (v *VaultProvider) SupportsCrossSigning() (bool, error) {
return true, nil
}
// Cleanup unmounts the configured intermediate PKI backend. It's fine to tear
// this down and recreate it on small config changes because the intermediate
// certs get bundled with the leaf certs, so there's no cost to the CA changing.
func (v *VaultProvider) Cleanup(providerTypeChange bool, otherConfig map[string]interface{}) error {
v.Stop()
if !providerTypeChange {
newConfig, err := ParseVaultCAConfig(otherConfig)
if err != nil {
return err
}
// if the intermeidate PKI path isn't changing we don't want to delete it as
// Cleanup is called after initializing the new provider
if newConfig.IntermediatePKIPath == v.config.IntermediatePKIPath {
return nil
}
}
err := v.unmountNamespaced(v.config.IntermediatePKINamespace, v.config.IntermediatePKIPath)
switch err {
case ErrBackendNotMounted, ErrBackendNotInitialized:
// suppress these errors if we didn't finish initialization before
return nil
default:
return err
}
}
// Stop shuts down the token renew goroutine.
func (v *VaultProvider) Stop() {
v.stopWatcher()
}
func (v *VaultProvider) PrimaryUsesIntermediate() {}
// We use raw path here
func (v *VaultProvider) mountNamespaced(namespace, path string, mountInfo *vaultapi.MountInput) error {
defer v.setNamespace(namespace)()
r := v.client.NewRequest("POST", fmt.Sprintf("/v1/sys/mounts/%s", path))
if err := r.SetJSONBody(mountInfo); err != nil {
return err
}
resp, err := v.client.RawRequest(r)
if resp != nil {
defer resp.Body.Close()
}
return err
}
func (v *VaultProvider) tuneMountNamespaced(namespace, path string, mountConfig *vaultapi.MountConfigInput) error {
defer v.setNamespace(namespace)()
r := v.client.NewRequest("POST", fmt.Sprintf("/v1/sys/mounts/%s/tune", path))
if err := r.SetJSONBody(mountConfig); err != nil {
return err
}
resp, err := v.client.RawRequest(r)
if resp != nil {
defer resp.Body.Close()
}
return err
}
func (v *VaultProvider) unmountNamespaced(namespace, path string) error {
defer v.setNamespace(namespace)()
r := v.client.NewRequest("DELETE", fmt.Sprintf("/v1/sys/mounts/%s", path))
resp, err := v.client.RawRequest(r)
if resp != nil {
defer resp.Body.Close()
}
return err
}
func makePathHelper(namespace, path string) string {
var fullPath string
if namespace != "" {
fullPath = fmt.Sprintf("/v1/%s/sys/mounts/%s", namespace, path)
} else {
fullPath = fmt.Sprintf("/v1/sys/mounts/%s", path)
}
return fullPath
}
func (v *VaultProvider) readNamespaced(namespace string, resource string) (*vaultapi.Secret, error) {
defer v.setNamespace(namespace)()
return v.client.Logical().Read(resource)
}
func (v *VaultProvider) writeNamespaced(namespace string, resource string, data map[string]interface{}) (*vaultapi.Secret, error) {
defer v.setNamespace(namespace)()
return v.client.Logical().Write(resource, data)
}
func (v *VaultProvider) setNamespace(namespace string) func() {
if namespace != "" {
v.clientMutex.Lock()
v.client.SetNamespace(namespace)
return func() {
v.client.SetNamespace(v.baseNamespace)
v.clientMutex.Unlock()
}
} else {
return func() {}
}
}
func ParseVaultCAConfig(raw map[string]interface{}) (*structs.VaultCAProviderConfig, error) {
config := structs.VaultCAProviderConfig{
CommonCAProviderConfig: defaultCommonConfig(),
}
decodeConf := &mapstructure.DecoderConfig{
DecodeHook: mapstructure.ComposeDecodeHookFunc(
structs.ParseDurationFunc(),
decode.HookTranslateKeys,
),
Result: &config,
WeaklyTypedInput: true,
}
decoder, err := mapstructure.NewDecoder(decodeConf)
if err != nil {
return nil, err
}
if err := decoder.Decode(raw); err != nil {
return nil, fmt.Errorf("error decoding config: %s", err)
}
if config.Token == "" && config.AuthMethod == nil {
return nil, fmt.Errorf("must provide a Vault token or configure a Vault auth method")
}
if config.Token != "" && config.AuthMethod != nil {
return nil, fmt.Errorf("only one of Vault token or Vault auth method can be provided, but not both")
}
if config.RootPKIPath == "" {
return nil, fmt.Errorf("must provide a valid path to a root PKI backend")
}
if !strings.HasSuffix(config.RootPKIPath, "/") {
config.RootPKIPath += "/"
}
if config.IntermediatePKIPath == "" {
return nil, fmt.Errorf("must provide a valid path for the intermediate PKI backend")
}
if !strings.HasSuffix(config.IntermediatePKIPath, "/") {
config.IntermediatePKIPath += "/"
}
if err := config.CommonCAProviderConfig.Validate(); err != nil {
return nil, err
}
return &config, nil
}
func vaultLogin(client *vaultapi.Client, authMethod *structs.VaultAuthMethod) (*vaultapi.Secret, error) {
// Adapted from https://www.vaultproject.io/docs/auth/kubernetes#code-example
loginPath, err := configureVaultAuthMethod(authMethod)
if err != nil {
return nil, err
}
resp, err := client.Logical().Write(loginPath, authMethod.Params)
if err != nil {
return nil, err
}
if resp == nil || resp.Auth == nil || resp.Auth.ClientToken == "" {
return nil, fmt.Errorf("login response did not return client token")
}
return resp, nil
}
func configureVaultAuthMethod(authMethod *structs.VaultAuthMethod) (loginPath string, err error) {
if authMethod.MountPath == "" {
authMethod.MountPath = authMethod.Type
}
switch authMethod.Type {
case VaultAuthMethodTypeKubernetes:
// For the Kubernetes Auth method, we will try to read the JWT token
// from the default service account file location if jwt was not provided.
if jwt, ok := authMethod.Params["jwt"]; !ok || jwt == "" {
serviceAccountToken, err := os.ReadFile(defaultK8SServiceAccountTokenPath)
if err != nil {
return "", err
}
authMethod.Params["jwt"] = string(serviceAccountToken)
}
loginPath = fmt.Sprintf("auth/%s/login", authMethod.MountPath)
// These auth methods require a username for the login API path.
case VaultAuthMethodTypeLDAP, VaultAuthMethodTypeUserpass, VaultAuthMethodTypeOkta, VaultAuthMethodTypeRadius:
// Get username from the params.
if username, ok := authMethod.Params["username"]; ok {
loginPath = fmt.Sprintf("auth/%s/login/%s", authMethod.MountPath, username)
} else {
return "", fmt.Errorf("failed to get 'username' from auth method params")
}
// This auth method requires a role for the login API path.
case VaultAuthMethodTypeOCI:
if role, ok := authMethod.Params["role"]; ok {
loginPath = fmt.Sprintf("auth/%s/login/%s", authMethod.MountPath, role)
} else {
return "", fmt.Errorf("failed to get 'role' from auth method params")
}
case VaultAuthMethodTypeToken:
return "", fmt.Errorf("'token' auth method is not supported via auth method configuration; " +
"please provide the token with the 'token' parameter in the CA configuration")
// The rest of the auth methods use auth/<auth method path> login API path.
case VaultAuthMethodTypeAliCloud,
VaultAuthMethodTypeAppRole,
VaultAuthMethodTypeAWS,
VaultAuthMethodTypeAzure,
VaultAuthMethodTypeCloudFoundry,
VaultAuthMethodTypeGitHub,
VaultAuthMethodTypeGCP,
VaultAuthMethodTypeJWT,
VaultAuthMethodTypeKerberos,
VaultAuthMethodTypeTLS:
loginPath = fmt.Sprintf("auth/%s/login", authMethod.MountPath)
default:
return "", fmt.Errorf("auth method %q is not supported", authMethod.Type)
}
return
}