140 lines
5.3 KiB
Plaintext
140 lines
5.3 KiB
Plaintext
---
|
|
layout: docs
|
|
page_title: Connect - Certificate Management
|
|
sidebar_title: 'Built-In CA'
|
|
sidebar_current: docs-connect-ca-consul
|
|
description: >-
|
|
Consul ships with a built-in CA system so that Connect can be easily enabled
|
|
out of the box. The built-in CA generates and stores the root certificate and
|
|
private key on Consul servers. It can also be configured with a custom
|
|
certificate and private key if needed.
|
|
---
|
|
|
|
# Built-In CA
|
|
|
|
Consul ships with a built-in CA system so that Connect can be
|
|
easily enabled out of the box. The built-in CA generates and stores the
|
|
root certificate and private key on Consul servers. It can also be
|
|
configured with a custom certificate and private key if needed.
|
|
|
|
If Connect is enabled and no CA provider is specified, the built-in
|
|
CA is the default provider used. The provider can be
|
|
[updated and rotated](/docs/connect/ca#root-certificate-rotation)
|
|
at any point to migrate to a new provider.
|
|
|
|
-> This page documents the specifics of the built-in CA provider.
|
|
Please read the [certificate management overview](/docs/connect/ca)
|
|
page first to understand how Consul manages certificates with configurable
|
|
CA providers.
|
|
|
|
## Configuration
|
|
|
|
The built-in CA provider has no required configuration. Enabling Connect
|
|
alone will configure the built-in CA provider and will automatically generate
|
|
a root certificate and private key:
|
|
|
|
```hcl
|
|
connect {
|
|
enabled = true
|
|
}
|
|
```
|
|
|
|
The configuration options are listed below. Note, the
|
|
first key is the value used in API calls and the second key (after the `/`)
|
|
is used if you're adding configuring to the agent's configuration file.
|
|
|
|
- `PrivateKey` / `private_key` (`string: ""`) - A PEM-encoded private key
|
|
for signing operations. This must match the private key used for the root
|
|
certificate if it is manually specified. If this is blank, a private key
|
|
is automatically generated.
|
|
|
|
- `RootCert` / `root_cert` (`string: ""`) - A PEM-encoded root certificate
|
|
to use. If this is blank, a root certificate is automatically generated
|
|
using the private key specified. If this is specified, the certificate
|
|
must be a valid
|
|
[SPIFFE SVID signing certificate](https://github.com/spiffe/spiffe/blob/master/standards/X509-SVID.md)
|
|
and the URI in the SAN must match the cluster identifier created at
|
|
bootstrap with the ".consul" TLD. The cluster identifier can be found
|
|
using the [CA List Roots endpoint](/api/connect/ca#list-ca-root-certificates).
|
|
|
|
There are also [common CA configuration options](/docs/agent/options#common-ca-config-options)
|
|
that are supported by all CA providers.
|
|
|
|
## Specifying a Custom Private Key and Root Certificate
|
|
|
|
By default, a root certificate and private key will be automatically
|
|
generated during the cluster's bootstrap. It is possible to configure
|
|
the Consul CA provider to use a specific private key and root certificate.
|
|
This is particularly useful if you have an external PKI system that doesn't
|
|
currently integrate with Consul directly.
|
|
|
|
To view the current CA configuration, use the [Get CA Configuration endpoint](/api/connect/ca#get-ca-configuration):
|
|
|
|
```bash
|
|
$ curl localhost:8500/v1/connect/ca/configuration
|
|
{
|
|
"Provider": "consul",
|
|
"Config": {
|
|
"LeafCertTTL": "72h",
|
|
"RotationPeriod": "2160h",
|
|
"IntermediateCertTTL": "8760h"
|
|
},
|
|
"CreateIndex": 5,
|
|
"ModifyIndex": 5
|
|
}
|
|
```
|
|
|
|
This is the default Connect CA configuration if nothing is explicitly set when
|
|
Connect is enabled - the PrivateKey and RootCert fields have not been set, so those have
|
|
been generated (as seen above in the roots list).
|
|
|
|
There are two ways to have the Consul CA use a custom private key and root certificate:
|
|
either through the `ca_config` section of the [Agent configuration](/docs/agent/options#connect_ca_config) (which can only be used during the cluster's
|
|
initial bootstrap) or through the [Update CA Configuration endpoint](/api/connect/ca#update-ca-configuration).
|
|
|
|
Currently consul requires that root certificates are valid [SPIFFE SVID Signing certificates](https://github.com/spiffe/spiffe/blob/master/standards/X509-SVID.md) and that the URI encoded
|
|
in the SAN is the cluster identifier created at bootstrap with the ".consul" TLD. In this
|
|
example, we will set the URI SAN to `spiffe://36cb52cd-4058-f811-0432-6798a240c5d3.consul`.
|
|
|
|
In order to use the Update CA Configuration HTTP endpoint, the private key and certificate
|
|
must be passed via JSON:
|
|
|
|
```bash
|
|
$ jq -n --arg key "$(cat root.key)" --arg cert "$(cat root.crt)" '
|
|
{
|
|
"Provider": "consul",
|
|
"Config": {
|
|
"LeafCertTTL": "72h",
|
|
"PrivateKey": $key,
|
|
"RootCert": $cert,
|
|
"RotationPeriod": "2160h",
|
|
"IntermediateCertTTL": "8760h"
|
|
}
|
|
}' > ca_config.json
|
|
```
|
|
|
|
The resulting `ca_config.json` file can then be used to update the active root certificate:
|
|
|
|
```bash
|
|
$ cat ca_config.json
|
|
{
|
|
"Provider": "consul",
|
|
"Config": {
|
|
"LeafCertTTL": "72h",
|
|
"PrivateKey": "-----BEGIN RSA PRIVATE KEY-----\nMIIEpAIBAAKCAQEArqiy1c3pbT3cSkjdEM1APALUareU...",
|
|
"RootCert": "-----BEGIN CERTIFICATE-----\nMIIDijCCAnKgAwIBAgIJAOFZ66em1qC7MA0GCSqGSIb3...",
|
|
"RotationPeriod": "2160h",
|
|
"IntermediateCertTTL": "8760h"
|
|
}
|
|
}
|
|
|
|
$ curl --request PUT --data @ca_config.json localhost:8500/v1/connect/ca/configuration
|
|
|
|
...
|
|
|
|
[INFO] connect: CA rotated to new root under provider "consul"
|
|
```
|
|
|
|
The cluster is now using the new private key and root certificate. Updating the CA config
|
|
this way also triggered a certificate rotation.
|