open-vault/website/source/docs/secrets/pki/index.html.md

layout	page_title	sidebar_current	description
docs	Secret Backend: PKI	docs-secrets-pki	The PKI secret backend for Vault generates TLS certificates.

PKI Secret Backend

Name: pki

The PKI secret backend for Vault generates X.509 certificates dynamically based on configured roles. This means services can get certificates needed for both client and server authentication without going through the usual manual process of generating a private key and CSR, submitting to a CA, and waiting for a verification and signing process to complete. Vault's built-in authentication and authorization mechanisms provide the verification functionality.

By keeping TTLs relatively short, revocations are less likely to be needed, keeping CRLs short and helping the backend scale to large workloads. This in turn allows each instance of a running application to have a unique certificate, eliminating sharing and the accompanying pain of revocation and rollover.

In addition, by allowing revocation to mostly be forgone, this backend allows for ephemeral certificates; certificates can be fetched and stored in memory upon application startup and discarded upon shutdown, without ever being written to disk.

This page will show a quick start for this backend. For detailed documentation on every path, use vault path-help after mounting the backend.

Considerations

To successfully deploy this backend, there are a number of important considerations to be aware of, as well as some preparatory steps that should be undertaken. You should read all of these before using this backend or generating the CA to use with this backend.

Be Careful with Root CAs

Vault storage is secure, but not as secure as a piece of paper in a bank vault. It is, after all, networked software. If your root CA is hosted outside of Vault, don't put it in Vault as well; instead, issue a shorter-lived intermediate CA certificate and put this into Vault. This aligns with industry best practices.

Since 0.4, the backend supports generating self-signed root CAs and creating and signing CSRs for intermediate CAs. In each instance, for security reasons, the private key can only be exported at generation time, and the ability to do so is part of the command path (so it can be put into ACL policies).

If you plan on using intermediate CAs with Vault, it is suggested that you let Vault create CSRs and do not export the private key, then sign those with your root CA (which may be a second mount of the pki backend).

One CA Certificate, One Backend

In order to vastly simplify both the configuration and codebase of the PKI backend, only one CA certificate is allowed per backend. If you want to issue certificates from multiple CAs, mount the PKI backend at multiple mount points with separate CA certificates in each.

This also provides a convenient method of switching to a new CA certificate while keeping CRLs valid from the old CA certificate; simply mount a new backend and issue from there.

A common pattern is to have one mount act as your root CA, and which is only used for signing intermediate CA CSRs mounted at other locations.

Keep certificate lifetimes short, for CRL's sake

This backend aligns with Vault's philosophy of short-lived secrets. As such it is not expected that CRLs will grow large; the only place a private key is ever returned is to the requesting client (this backend does not store generated private keys, except for CA certificates). In most cases, if the key is lost, the certificate can simply be ignored, as it will expire shortly.

If a certificate must truly be revoked, the normal Vault revocation function can be used; alternately a root token can be used to revoke the certificate using the certificate's serial number. Any revocation action will cause the CRL to be regenerated. When the CRL is regenerated, any expired certificates are removed from the CRL (and any revoked, expired certificate are removed from backend storage).

This backend does not support multiple CRL endpoints with sliding date windows; often such mechanisms will have the transition point a few days apart, but this gets into the expected realm of the actual certificate validity periods issued from this backend. A good rule of thumb for this backend would be to simply not issue certificates with a validity period greater than your maximum comfortable CRL lifetime. Alternately, you can control CRL caching behavior on the client to ensure that checks happen more often.

Often multiple endpoints are used in case a single CRL endpoint is down so that clients don't have to figure out what to do with a lack of response. Run Vault in HA mode, and the CRL endpoint should be available even if a particular node is down.

You must configure issuing/CRL/OCSP information in advance

This backend serves CRLs from a predictable location, but it is not possible for the backend to know where it is running. Therefore, you must configure desired URLs for the issuing certificate, CRL distribution points, and OCSP servers manually using the config/urls endpoint. It is supported to have more than one of each of these by passing in the multiple URLs as a comma-separated string parameter.

No OCSP support, yet

Vault's architecture does not currently allow for a binary protocol such as OCSP to be supported by a backend. As such, you should configure your software to use CRLs for revocation information, with a caching lifetime that feels good to you. Since you are following the advice above about keeping lifetimes short (right?), CRLs should not grow too large, however, you can configure alternate CRL and/or OCSP servers using config/urls if you wish.

If you are using issued certificates for client authentication to Vault, note that as of 0.4, the cert authentication endpoint supports being pushed CRLs, but it cannot read CRLs directly from this backend.

Safe Minimums

Since its inception, this backend has enforced SHA256 for signature hashes rather than SHA1. As of 0.5.1, a minimum of 2048 bits for RSA keys is also enforced. Software that can handle SHA256 signatures should also be able to handle 2048-bit keys, and 1024-bit keys are considered unsafe and are disallowed in the Internet PKI.

Token Lifetimes and Revocation

When a token expires, it revokes all leases associated with it. This means that long-lived CA certs need correspondingly long-lived tokens, something that is easy to forget. Starting with 0.6, root and intermediate CA certs no longer have associated leases, to prevent unintended revocation when not using a token with a long enough lifetime. To revoke these certificates, use the pki/revoke endpoint.

Quick Start

Mount the backend

The first step to using the PKI backend is to mount it. Unlike the generic backend, the pki backend is not mounted by default.

$ vault mount pki
Successfully mounted 'pki' at 'pki'!

Configure a CA certificate

Next, Vault must be configured with a CA certificate and associated private key. We'll take advantage of the backend's self-signed root generation support, but Vault also supports generating an intermediate CA (with a CSR for signing) or setting a PEM-encoded certificate and private key bundle directly into the backend.

Generally you'll want a root certificate to only be used to sign CA intermediate certificates, but for this example we'll proceed as if you will issue certificates directly from the root. As it's a root, we'll want to set a long maximum life time for the certificate; since it honors the maximum mount TTL, first we adjust that:

$ vault mount-tune -max-lease-ttl=87600h pki
Successfully tuned mount 'pki'!

That sets the maximum TTL for secrets issued from the mount to 10 years. (Note that roles can further restrict the maximum TTL.)

Now, we generate our root certificate:

$ vault write pki/root/generate/internal common_name=myvault.com ttl=87600h
Key             Value
certificate     -----BEGIN CERTIFICATE-----
MIIDvTCCAqWgAwIBAgIUAsza+fvOw+Xh9ifYQ0gNN0ruuWcwDQYJKoZIhvcNAQEL
BQAwFjEUMBIGA1UEAxMLbXl2YXVsdC5jb20wHhcNMTUxMTE5MTYwNDU5WhcNMjUx
MTE2MTYwNDU5WjAWMRQwEgYDVQQDEwtteXZhdWx0LmNvbTCCASIwDQYJKoZIhvcN
AQEBBQADggEPADCCAQoCggEBAMUhH4OLf/sa6GuJONGC/CWLY7nDbfH8jAaCKgqV
eJ81KrmcgP8WPhoFsYHFQEQXQZcrJagwYfm19jYn3CaqrYPbciv9bcWi+ECxZV3x
Hs/YdCFk7KgDGCci37w+cy6fSB943FKJqqVbvPv0odmq6LvgGGgneznvuvkIrOWG
qVDrDdvbEZ01XAyzUQJaaiJXExN+6xm1HcBoypCP8ZjjnXHcFQvw2QBItLRU7iUd
ESFgbrkrSPW3HA6KF0ov2qFMoHTiQ6aM4KaHPmXcFPicugYR9owZfZ4lwWJCqT7j
EkhokaMgHnvyRScuiRZhQm8ppHZoYsqrc3glfEuxGHkS+0cCAwEAAaOCAQEwgf4w
DgYDVR0PAQH/BAQDAgGuMBMGA1UdJQQMMAoGCCsGAQUFBwMJMA8GA1UdEwEB/wQF
MAMBAf8wHQYDVR0OBBYEFLvAbt0eUUOoo7hjKiQM2bRqDKrZMB8GA1UdIwQYMBaA
FLvAbt0eUUOoo7hjKiQM2bRqDKrZMDsGCCsGAQUFBwEBBC8wLTArBggrBgEFBQcw
AoYfaHR0cDovLzEyNy4wLjAuMTo4MjAwL3YxL3BraS9jYTAWBgNVHREEDzANggtt
eXZhdWx0LmNvbTAxBgNVHR8EKjAoMCagJKAihiBodHRwOi8vMTI3LjAuMC4xOjgy
MDAvdjEvcGtpL2NybDANBgkqhkiG9w0BAQsFAAOCAQEAVSgIRl6XJs95D7iXGzeQ
Ab8OIei779k0pD7xxS/+knY3TM6733zL/LXs4BEL3wfcQWoDrMtCW0Ook455sAOE
PSnTaZYQSH/F74VawWhSee4ZyiWq+sTUI4IzqYG3IS36mCyb0t6RxEb3aoQ87WHs
BHIB6uWbj6WoGHYM8ESxY89aY9jnX3xSs1HuluVW1uPrpIoa/eudpyV40Y1+9RNM
6fCX5LHGM7vKYxqvudYe+7G1MdKVBQg17h6XuieiUswVt2/HvDlNr+9DHrUla9Ve
Ig43v+grirlG7DrAr6Aiu/MVWKJP6CvNwG/XzrGaqd6KqSsE+8oIGR9tCTuPxI6v
SQ==
-----END CERTIFICATE-----
expiration      1.763309099e+09
issuing_ca      -----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
serial_number   02:cc:da:f9:fb:ce:c3:e5:e1:f6:27:d8:43:48:0d:37:4a:ee:b9:67

The returned certificate is purely informational; it and its private key are safely stored in the backend mount.

Set URL configuration

Generated certificates can have the CRL location and the location of the issuing certificate encoded. These values must be set manually, but can be changed at any time.

$ vault write pki/config/urls issuing_certificates="http://127.0.0.1:8200/v1/pki/ca" crl_distribution_points="http://127.0.0.1:8200/v1/pki/crl"
Success! Data written to: pki/ca/urls

Configure a role

The next step is to configure a role. A role is a logical name that maps to a policy used to generate those credentials. For example, let's create an "example-dot-com" role:

$ vault write pki/roles/example-dot-com \
    allowed_domains="example.com" \
    allow_subdomains="true" max_ttl="72h"
Success! Data written to: pki/roles/example-dot-com

Generate credentials

By writing to the roles/example-dot-com path we are defining the example-dot-com role. To generate a new set of credentials, we simply write to the issue endpoint with that role name: Vault is now configured to create and manage certificates!

$ vault write pki/issue/example-dot-com \
    common_name=blah.example.com
Key                     Value
lease_id                pki/issue/example-dot-com/32db49a9-61dd-f9ca-f4a6-aaefafe53739
lease_duration          259199
lease_renewable         false
certificate             -----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
issuing_ca              -----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
private_key             -----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
private_key_type        rsa
serial_number           14:c9:de:ee:ba:35:0f:2b:e9:65:5f:94:44:73:0f:b7:3d:ef:bf:d3

Vault has now generated a new set of credentials using the example-dot-com role configuration. Here we see the dynamically generated private key and certificate. The issuing CA certificate is returned as well.

Using ACLs, it is possible to restrict using the pki backend such that trusted operators can manage the role definitions, and both users and applications are restricted in the credentials they are allowed to read.

If you get stuck at any time, simply run vault path-help pki or with a subpath for interactive help output.

API

/pki/ca(/pem)

GET

Description

Retrieves the CA certificate *in raw DER-encoded form*. This is a bare endpoint that does not return a standard Vault data structure. If `/pem` is added to the endpoint, the CA certificate is returned in PEM format.

This is an unauthenticated endpoint.

Method

GET

URL

`/pki/ca(/pem)`

Parameters

None

Returns

```
<binary DER-encoded certficiate>
```

/pki/cert/

GET

Description

Retrieves one of a selection of certificates. Valid values: `ca` for the CA certificate, `crl` for the current CRL, or a serial number in either hyphen-separated or colon-separated octal format. This endpoint returns the certificate in PEM formatting in the `certificate` key of the JSON object.

This is an unauthenticated endpoint.

Method

GET

URL

`/pki/cert/`

Parameters

None

Returns

```javascript
{
  "data": {
    "certificate": "-----BEGIN CERTIFICATE-----\nMIIGmDCCBYCgAwIBAgIHBzEB3fTzhTANBgkqhkiG9w0BAQsFADCBjDELMAkGA1UE\n..."
  }
}
...
```

/pki/config/ca

POST

Description

Allows submitting the CA information for the backend via a PEM file containing the CA certificate and its private key, concatenated. Not needed if you are generating a self-signed root certificate, and not used if you have a signed intermediate CA certificate with a generated key (use the `/pki/intermediate/set-signed` endpoint for that). _If you have already set a certificate and key, they will be overridden._

The information can be provided from a file via a `curl` command similar to the following:

```text
$ curl \
    -H "X-Vault-Token:06b9d..." \
    -X POST \
    --data "@cabundle.json" \
    http://127.0.0.1:8200/v1/pki/config/ca
```

Note that if you provide the data through the HTTP API it must be
JSON-formatted, with newlines replaced with `\n`, like so:

```javascript
{
  "pem_bundle": "-----BEGIN RSA PRIVATE KEY-----\n...\n-----END CERTIFICATE-----"
}
```

Method

POST

URL

`/pki/config/ca`

Parameters

• pem_bundle required The key and certificate concatenated in PEM format.

Returns

A `204` response code.

/pki/config/crl

GET

Description

Allows getting the duration for which the generated CRL should be marked valid.

Method

GET

URL

`/pki/config/crl`

Parameters

None

Returns

```javascript
{
  "lease_id": "",
  "renewable": false,
  "lease_duration": 0,
  "data": {
      "expiry": "72h"
    },
  "auth": null
}
```

POST

Description

Allows setting the duration for which the generated CRL should be marked valid.

Method

POST

URL

`/pki/config/crl`

Parameters

• expiry required The time until expiration. Defaults to `72h`.

Returns

A `204` response code.

/pki/config/urls

GET

Description

Fetch the URLs to be encoded in generated certificates.

Method

GET

URL

`/pki/config/urls`

Parameters

None

Returns

```javascript
{
  "lease_id": "",
  "renewable": false,
  "lease_duration": 0,
  "data": {
      "issuing_certificates": [<url1>, <url2>],
      "crl_distribution_points": [<url1>, <url2>],
      "ocsp_servers": [<url1>, <url2>],
    },
  "auth": null
}
```

POST

Description

Allows setting the issuing certificate endpoints, CRL distribution points, and OCSP server endpoints that will be encoded into issued certificates. You can update any of the values at any time without affecting the other existing values. To remove the values, simply use a blank string as the parameter.

Method

POST

URL

`/pki/config/urls`

Parameters

• issuing_certificates optional The URL values for the Issuing Certificate field.
• crl_distribution_points optional The URL values for the CRL Distribution Points field.
• ocsp_servers optional The URL values for the OCSP Servers field.

Returns

A `204` response code.

/pki/crl(/pem)

GET

Description

Retrieves the current CRL *in raw DER-encoded form*. This endpoint is suitable for usage in the CRL Distribution Points extension in a CA certificate. This is a bare endpoint that does not return a standard Vault data structure. If `/pem` is added to the endpoint, the CRL is returned in PEM format.

This is an unauthenticated endpoint.

Method

GET

URL

`/pki/crl(/pem)`

Parameters

None

Returns

```
<binary DER-encoded CRL>
```

/pki/crl/rotate

GET

Description

This endpoint forces a rotation of the CRL. This can be used by administrators to cut the size of the CRL if it contains a number of certificates that have now expired, but has not been rotated due to no further certificates being revoked.

Method

GET

URL

`/pki/crl/rotate`

Parameters

None

Returns

```javascript
{
  "data": {
    "success": true
  }
}
```

/pki/intermediate/generate

POST

Description

Generates a new private key and a CSR for signing. If using Vault as a root, and for many other CAs, the various parameters on the final certificate are set at signing time and may or may not honor the parameters set here. _This will overwrite any previously existing CA private key._ If the path ends with `exported`, the private key will be returned in the response; if it is `internal` the private key will not be returned and *cannot be retrieved later*.

This is mostly meant as a helper function, and not all possible parameters that can be set in a CSR are supported.

Method

POST

URL

`/pki/intermediate/generate/[exported|internal]`

Parameters

• common_name required The requested CN for the certificate.
• alt_names optional Requested Subject Alternative Names, in a comma-delimited list. These can be host names or email addresses; they will be parsed into their respective fields.
• ip_sans optional Requested IP Subject Alternative Names, in a comma-delimited list.
• format optional Format for returned data. Can be `pem`, `der`, or `pem_bundle`; defaults to `pem`. If `der`, the output is base64 encoded. If `pem_bundle`, the `csr` field will contain the private key (if exported) and CSR, concatenated.
• key_type optional Desired key type; must be `rsa` or `ec`. Defaults to `rsa`.
• key_bits optional The number of bits to use. Defaults to `2048`. Must be changed to a valid value if the `key_type` is `ec`.
• exclude_cn_from_sans optional If set, the given `common_name` will not be included in DNS or Email Subject Alternate Names (as appropriate). Useful if the CN is not a hostname or email address, but is instead some human-readable identifier.

Returns

```javascript
{
  "lease_id": "",
  "renewable": false,
  "lease_duration": 21600,
  "data": {
    "csr": "-----BEGIN CERTIFICATE REQUEST-----\nMIIDzDCCAragAwIBAgIUOd0ukLcjH43TfTHFG9qE0FtlMVgwCwYJKoZIhvcNAQEL\n...\numkqeYeO30g1uYvDuWLXVA==\n-----END CERTIFICATE REQUEST-----\n",
    "private_key": "-----BEGIN RSA PRIVATE KEY-----\\nMIIEpAIBAAKCAQEAwsANtGz9gS3o5SwTSlOG1l-----END RSA PRIVATE KEY-----",
    "private_key_type": "rsa"
    },
  "warnings": null,
  "auth": null
}
```

/pki/intermediate/set-signed

POST

Description

Allows submitting the signed CA certificate corresponding to a private key generated via `/pki/intermediate/generate`. The certificate should be submitted in PEM format; see the documentation for `/pki/config/ca` for some hints on submitting.

Method

POST

URL

`/pki/intermediate/set-signed`

Parameters

• certificate required The certificate in PEM format.

Returns

A `204` response code.

/pki/issue/

POST

Description

Generates a new set of credentials (private key and certificate) based on the role named in the endpoint. The issuing CA certificate is returned as well, so that only the root CA need be in a client's trust store.

*The private key is _not_ stored. If you do not save the private key, you will need to request a new certificate.*

Method

POST

URL

`/pki/issue/`

Parameters

• common_name required The requested CN for the certificate. If the CN is allowed by role policy, it will be issued.
• alt_names optional Requested Subject Alternative Names, in a comma-delimited list. These can be host names or email addresses; they will be parsed into their respective fields. If any requested names do not match role policy, the entire request will be denied.
• ip_sans optional Requested IP Subject Alternative Names, in a comma-delimited list. Only valid if the role allows IP SANs (which is the default).
• ttl optional Requested Time To Live. Cannot be greater than the role's `max_ttl` value. If not provided, the role's `ttl` value will be used. Note that the role values default to system values if not explicitly set.
• format optional Format for returned data. Can be `pem`, `der`, or `pem_bundle`; defaults to `pem`. If `der`, the output is base64 encoded. If `pem_bundle`, the `certificate` field will contain the private key, certificate, and issuing CA, concatenated.
• exclude_cn_from_sans optional If set, the given `common_name` will not be included in DNS or Email Subject Alternate Names (as appropriate). Useful if the CN is not a hostname or email address, but is instead some human-readable identifier.

Returns

```javascript
{
  "lease_id": "pki/issue/test/7ad6cfa5-f04f-c62a-d477-f33210475d05",
  "renewable": false,
  "lease_duration": 21600,
  "data": {
    "certificate": "-----BEGIN CERTIFICATE-----\nMIIDzDCCAragAwIBAgIUOd0ukLcjH43TfTHFG9qE0FtlMVgwCwYJKoZIhvcNAQEL\n...\numkqeYeO30g1uYvDuWLXVA==\n-----END CERTIFICATE-----\n",
    "issuing_ca": "-----BEGIN CERTIFICATE-----\nMIIDUTCCAjmgAwIBAgIJAKM+z4MSfw2mMA0GCSqGSIb3DQEBCwUAMBsxGTAXBgNV\n...\nG/7g4koczXLoUM3OQXd5Aq2cs4SS1vODrYmgbioFsQ3eDHd1fg==\n-----END CERTIFICATE-----\n",
    "private_key": "-----BEGIN RSA PRIVATE KEY-----\nMIIEowIBAAKCAQEAnVHfwoKsUG1GDVyWB1AFroaKl2ImMBO8EnvGLRrmobIkQvh+\n...\nQN351pgTphi6nlCkGPzkDuwvtxSxiCWXQcaxrHAL7MiJpPzkIBq1\n-----END RSA PRIVATE KEY-----\n",
    "private_key_type": "rsa",
    "serial_number": "39:dd:2e:90:b7:23:1f:8d:d3:7d:31:c5:1b:da:84:d0:5b:65:31:58"
    },
  "warnings": "",  
  "auth": null
}
```

/pki/revoke

POST

Description

Revokes a certificate using its serial number. This is an alternative option to the standard method of revoking using Vault lease IDs. A successful revocation will rotate the CRL.

Method

POST

URL

`/pki/revoke`

Parameters

• serial_number required The serial number of the certificate to revoke, in hyphen-separated or colon-separated octal.

Returns

```javascript
{
  "data": {
    "revocation_time": 1433269787
  }
}
```

/pki/roles/

POST

Description

Creates or updates the role definition. Note that the `allowed_domains`, `allow_subdomains`, and `allow_any_name` attributes are additive; between them nearly and across multiple roles nearly any issuing policy can be accommodated. `server_flag`, `client_flag`, and `code_signing_flag` are additive as well. If a client requests a certificate that is not allowed by the CN policy in the role, the request is denied.

Method

POST

URL

`/pki/roles/`

Parameters

• ttl optional The Time To Live value provided as a string duration with time suffix. Hour is the largest suffix. If not set, uses the system default value or the value of `max_ttl`, whichever is shorter.
• max_ttl optional The maximum Time To Live provided as a string duration with time suffix. Hour is the largest suffix. If not set, defaults to the system maximum lease TTL.
• allow_localhost optional If set, clients can request certificates for `localhost` as one of the requested common names. This is useful for testing and to allow clients on a single host to talk securely. Defaults to true.
• allowed_domains optional Designates the domains of the role, provided as a comma-separated list. This is used with the `allow_bare_domains` and `allow_subdomains` options. There is no default.
• allow_bare_domains optional If set, clients can request certificates matching the value of the actual domains themselves; e.g. if a configured domain set with `allowed_domains` is `example.com`, this allows clients to actually request a certificate containing the name `example.com` as one of the DNS values on the final certificate. In some scenarios, this can be considered a security risk. Defaults to false.
• allow_subdomains optional If set, clients can request certificates with CNs that are subdomains of the CNs allowed by the other role options. _This includes wildcard subdomains._ For example, an `allowed_domains` value of `example.com` with this option set to true will allow `foo.example.com` and `bar.example.com` as well as `*.example.com`. This is redundant when using the `allow_any_name` option. Defaults to `false`.
• allow_any_name optional If set, clients can request any CN. Useful in some circumstances, but make sure you understand whether it is appropriate for your installation before enabling it. Defaults to `false`.
• enforce_hostnames optional If set, only valid host names are allowed for CNs, DNS SANs, and the host part of email addresses. Defaults to `true`.
• allow_ip_sans optional If set, clients can request IP Subject Alternative Names. No authorization checking is performed except to verify that the given values are valid IP addresses. Defaults to `true`.
• server_flag optional If set, certificates are flagged for server use. Defaults to `true`.
• client_flag optional If set, certificates are flagged for client use. Defaults to `true`.
• code_signing_flag optional If set, certificates are flagged for code signing use. Defaults to `false`.
• email_protection_flag optional If set, certificates are flagged for email protection use. Defaults to `false`.
• key_type optional The type of key to generate for generated private keys. Currently, `rsa` and `ec` are supported. Defaults to `rsa`.
• key_bits optional The number of bits to use for the generated keys. Defaults to `2048`; this will need to be changed for `ec` keys. See https://golang.org/pkg/crypto/elliptic/#Curve for an overview of allowed bit lengths for `ec`.
• use_csr_common_name optional If set, when used with the CSR signing endpoint, the common name in the CSR will be used instead of taken from the JSON data. This does `not` include any requested SANs in the CSR. Defaults to `false`.

Returns

A `204` response code.

GET

Description

Queries the role definition.

Method

GET

URL

`/pki/roles/`

Parameters

None

Returns

```javascript
{
  "data": {
    "allow_any_name": false,
    "allow_ip_sans": true,
    "allow_localhost": true,
    "allow_subdomains": false,
    "allowed_domains": "example.com,foobar.com",
    "client_flag": true,
    "code_signing_flag": false,
    "key_bits": 2048,
    "key_type": "rsa",
    "ttl": "6h",
    "max_ttl": "12h",
    "server_flag": true
  }
}
```

LIST

Description

Returns a list of available roles. Only the role names are returned, not any values.

Method

GET

URL

`/roles/?list=true`

Parameters

None

Returns

{
  "auth": null,
  "data": {
    "keys": ["dev", "prod"]
  },
  "lease_duration": 2592000,
  "lease_id": "",
  "renewable": false
}

DELETE

Description

Deletes the role definition. Deleting a role does not revoke certificates previously issued under this role.

Method

DELETE

URL

`/pki/roles/`

Parameters

None

Returns

A `204` response code.

/pki/root/generate

POST

Description

Generates a new self-signed CA certificate and private key. _This will overwrite any previously-existing private key and certificate._ If the path ends with `exported`, the private key will be returned in the response; if it is `internal` the private key will not be returned and *cannot be retrieved later*. Distribution points use the values set via `config/urls`.

As with other issued certificates, Vault will automatically revoke the generated root at the end of its lease period; the CA certificate will sign its own CRL.

Method

POST

URL

`/pki/root/generate/[exported|internal]`

Parameters

• common_name required The requested CN for the certificate.
• alt_names optional Requested Subject Alternative Names, in a comma-delimited list. These can be host names or email addresses; they will be parsed into their respective fields.
• ip_sans optional Requested IP Subject Alternative Names, in a comma-delimited list.
• ttl optional Requested Time To Live (after which the certificate will be expired). This cannot be larger than the mount max (or, if not set, the system max).
• format optional Format for returned data. Can be `pem`, `der`, or `pem_bundle`; defaults to `pem`. If `der`, the output is base64 encoded. If `pem_bundle`, the `certificate` field will contain the private key (if exported), certificate, and issuing CA, concatenated.
• key_type optional Desired key type; must be `rsa` or `ec`. Defaults to `rsa`.
• key_bits optional The number of bits to use. Defaults to `2048`. Must be changed to a valid value if the `key_type` is `ec`.
• max_path_length optional If set, the maximum path length to encode in the generated certificate. Defaults to `-1`, which means no limit. unless the signing certificate has a maximum path length set, in which case the path length is set to one less than that of the signing certificate. A limit of `0` means a literal path length of zero.
• exclude_cn_from_sans optional If set, the given `common_name` will not be included in DNS or Email Subject Alternate Names (as appropriate). Useful if the CN is not a hostname or email address, but is instead some human-readable identifier.

Returns

```javascript
{
  "lease_id": "",
  "lease_duration": 0,
  "renewable": false,
  "data": {
    "certificate": "-----BEGIN CERTIFICATE-----\nMIIDzDCCAragAwIBAgIUOd0ukLcjH43TfTHFG9qE0FtlMVgwCwYJKoZIhvcNAQEL\n...\numkqeYeO30g1uYvDuWLXVA==\n-----END CERTIFICATE-----\n",
    "issuing_ca": "-----BEGIN CERTIFICATE-----\nMIIDzDCCAragAwIBAgIUOd0ukLcjH43TfTHFG9qE0FtlMVgwCwYJKoZIhvcNAQEL\n...\numkqeYeO30g1uYvDuWLXVA==\n-----END CERTIFICATE-----\n",
    "serial": "39:dd:2e:90:b7:23:1f:8d:d3:7d:31:c5:1b:da:84:d0:5b:65:31:58"
    },
  "auth": null
}
```

/pki/root/sign-intermediate

POST

Description

Uses the configured CA certificate to issue a certificate with appropriate values for acting as an intermediate CA. Distribution points use the values set via `config/urls`. Values set in the CSR are ignored unless `use_csr_values` is set to true, in which case the values from the CSR are used verbatim.

Method

POST

URL

`/pki/root/sign-intermediate`

Parameters

• csr required The PEM-encoded CSR.
• common_name required The requested CN for the certificate.
• alt_names optional Requested Subject Alternative Names, in a comma-delimited list. These can be host names or email addresses; they will be parsed into their respective fields.
• ip_sans optional Requested IP Subject Alternative Names, in a comma-delimited list.
• ttl optional Requested Time To Live (after which the certificate will be expired). This cannot be larger than the mount max (or, if not set, the system max).
• format optional Format for returned data. Can be `pem`, `der`, or `pem_bundle`; defaults to `pem`. If `der`, the output is base64 encoded. If `pem_bundle`, the `certificate` field will contain the certificate and issuing CA, concatenated.
• max_path_length optional If set, the maximum path length to encode in the generated certificate. Defaults to `-1`, which means no limit. unless the signing certificate has a maximum path length set, in which case the path length is set to one less than that of the signing certificate. A limit of `0` means a literal path length of zero.
• exclude_cn_from_sans optional If set, the given `common_name` will not be included in DNS or Email Subject Alternate Names (as appropriate). Useful if the CN is not a hostname or email address, but is instead some human-readable identifier.
• use_csr_values optional If set to `true`, then: 1) Subject information, including names and alternate names, will be preserved from the CSR rather than using the values provided in the other parameters to this path; 2) Any key usages (for instance, non-repudiation) requested in the CSR will be added to the basic set of key usages used for CA certs signed by this path; 3) Extensions requested in the CSR will be copied into the issued certificate.

Returns

```javascript
{
  "lease_id": "",
  "renewable": false,
  "lease_duration": 0,
  "data": {
    "certificate": "-----BEGIN CERTIFICATE-----\nMIIDzDCCAragAwIBAgIUOd0ukLcjH43TfTHFG9qE0FtlMVgwCwYJKoZIhvcNAQEL\n...\numkqeYeO30g1uYvDuWLXVA==\n-----END CERTIFICATE-----\n",
    "issuing_ca": "-----BEGIN CERTIFICATE-----\nMIIDUTCCAjmgAwIBAgIJAKM+z4MSfw2mMA0GCSqGSIb3DQEBCwUAMBsxGTAXBgNV\n...\nG/7g4koczXLoUM3OQXd5Aq2cs4SS1vODrYmgbioFsQ3eDHd1fg==\n-----END CERTIFICATE-----\n",
    "serial": "39:dd:2e:90:b7:23:1f:8d:d3:7d:31:c5:1b:da:84:d0:5b:65:31:58"
    },
  "auth": null
}
```

/pki/sign/

POST

Description

Signs a new certificate based upon the provided CSR and the supplied parameters, subject to the restrictions contained in the role named in the endpoint. The issuing CA certificate is returned as well, so that only the root CA need be in a client's trust store.

Method

POST

URL

`/pki/sign/`

Parameters

• csr required The PEM-encoded CSR.
• common_name required The requested CN for the certificate. If the CN is allowed by role policy, it will be issued.
• alt_names optional Requested Subject Alternative Names, in a comma-delimited list. These can be host names or email addresses; they will be parsed into their respective fields. If any requested names do not match role policy, the entire request will be denied.
• ip_sans optional Requested IP Subject Alternative Names, in a comma-delimited list. Only valid if the role allows IP SANs (which is the default).
• ttl optional Requested Time To Live. Cannot be greater than the role's `max_ttl` value. If not provided, the role's `ttl` value will be used. Note that the role values default to system values if not explicitly set.
• format optional Format for returned data. Can be `pem`, `der`, or `pem_bundle`; defaults to `pem`. If `der`, the output is base64 encoded. If `pem_bundle`, the `certificate` field will contain the certificate and issuing CA, concatenated.
• exclude_cn_from_sans optional If set, the given `common_name` will not be included in DNS or Email Subject Alternate Names (as appropriate). Useful if the CN is not a hostname or email address, but is instead some human-readable identifier.

Returns

```javascript
{
  "lease_id": "pki/sign/test/7ad6cfa5-f04f-c62a-d477-f33210475d05",
  "renewable": false,
  "lease_duration": 21600,
  "data": {
    "certificate": "-----BEGIN CERTIFICATE-----\nMIIDzDCCAragAwIBAgIUOd0ukLcjH43TfTHFG9qE0FtlMVgwCwYJKoZIhvcNAQEL\n...\numkqeYeO30g1uYvDuWLXVA==\n-----END CERTIFICATE-----\n",
    "issuing_ca": "-----BEGIN CERTIFICATE-----\nMIIDUTCCAjmgAwIBAgIJAKM+z4MSfw2mMA0GCSqGSIb3DQEBCwUAMBsxGTAXBgNV\n...\nG/7g4koczXLoUM3OQXd5Aq2cs4SS1vODrYmgbioFsQ3eDHd1fg==\n-----END CERTIFICATE-----\n",
    "serial": "39:dd:2e:90:b7:23:1f:8d:d3:7d:31:c5:1b:da:84:d0:5b:65:31:58"
    },
  "auth": null
}
```

/pki/sign-verbatim

POST

Description

Signs a new certificate based upon the provided CSR. Values are taken verbatim from the CSR; the _only_ restriction is that this endpoint will refuse to issue an intermediate CA certificate (see the `/pki/root/sign-intermediate` endpoint for that functionality.) _This is a potentially dangerous endpoint and only highly trusted users should have access._

Method

POST

URL

`/pki/sign-verbatim`

Parameters

• csr required The PEM-encoded CSR.
• ttl optional Requested Time To Live. Cannot be greater than the mount's `max_ttl` value. If not provided, the mount's `ttl` value will be used, which defaults to system values if not explicitly set.
• format optional Format for returned data. Can be `pem`, `der`, or `pem_bundle`; defaults to `pem`. If `der`, the output is base64 encoded. If `pem_bundle`, the `certificate` field will contain the certificate and issuing CA, concatenated.

Returns

```javascript
{
  "lease_id": "pki/sign-verbatim/7ad6cfa5-f04f-c62a-d477-f33210475d05",
  "renewable": false,
  "lease_duration": 21600,
  "data": {
    "certificate": "-----BEGIN CERTIFICATE-----\nMIIDzDCCAragAwIBAgIUOd0ukLcjH43TfTHFG9qE0FtlMVgwCwYJKoZIhvcNAQEL\n...\numkqeYeO30g1uYvDuWLXVA==\n-----END CERTIFICATE-----\n",
    "issuing_ca": "-----BEGIN CERTIFICATE-----\nMIIDUTCCAjmgAwIBAgIJAKM+z4MSfw2mMA0GCSqGSIb3DQEBCwUAMBsxGTAXBgNV\n...\nG/7g4koczXLoUM3OQXd5Aq2cs4SS1vODrYmgbioFsQ3eDHd1fg==\n-----END CERTIFICATE-----\n",
    "serial": "39:dd:2e:90:b7:23:1f:8d:d3:7d:31:c5:1b:da:84:d0:5b:65:31:58"
    },
  "auth": null
}
```

/pki/tidy

POST

Description

Allows tidying up the backend storage and/or CRL by removing certificates that have expired and are past a certain buffer period beyond their expiration time.

Method

POST

URL

`/pki/tidy`

Parameters

• tidy_cert_store optional Whether to tidy up the certificate store. Defaults to `false`.
• tidy_revocation_list optional Whether to tidy up the revocation list (CRL). Defaults to `false`.
• safety_buffer optional A duration (given as an integer number of seconds or a string; defaults to `72h`) used as a safety buffer to ensure certificates are not expunged prematurely; as an example, this can keep certificates from being removed from the CRL that, due to clock skew, might still be considered valid on other hosts. For a certificate to be expunged, the time must be after the expiration time of the certificate (according to the local clock) plus the duration of `safety_buffer`.

Returns

A `204` status code.