Martin c38c5763ed
Fix: Add missing iam:TagUser permission (#28757)
Co-authored-by: Yoko Hyakuna <yoko@hashicorp.com>
2024-11-04 09:20:37 -08:00

644 lines
25 KiB
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---
layout: docs
page_title: AWS - Secrets Engines
description: |-
The AWS secrets engine for Vault generates access keys dynamically based on
IAM policies.
---
# AWS secrets engine
The AWS secrets engine generates AWS access credentials dynamically based on IAM
policies. This generally makes working with AWS IAM easier, since it does not
involve clicking in the web UI. Additionally, the process is codified and mapped
to internal auth methods (such as LDAP). The AWS IAM credentials are time-based
and are automatically revoked when the Vault lease expires.
Vault supports three different types of credentials to retrieve from AWS:
1. `iam_user`: Vault will create an IAM user for each lease, attach the managed
and inline IAM policies as specified in the role to the user, and if a
[permissions
boundary](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_boundaries.html)
is specified on the role, the permissions boundary will also be attached.
Vault will then generate an access key and secret key for the IAM user and
return them to the caller. IAM users have no session tokens and so no
session token will be returned. Vault will delete the IAM user upon reaching the TTL expiration.
2. `assumed_role`: Vault will call
[sts:AssumeRole](https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html)
and return the access key, secret key, and session token to the caller.
3. `federation_token`: Vault will call
[sts:GetFederationToken](https://docs.aws.amazon.com/STS/latest/APIReference/API_GetFederationToken.html)
passing in the supplied AWS policy document and return the access key, secret
key, and session token to the caller.
4. `session_token`: Vault will call
[sts:GetSessionToken](https://docs.aws.amazon.com/STS/latest/APIReference/API_GetSessionToken.html)
and return the access key, secret key, and session token to the caller.
### Static roles
The AWS secrets engine supports the concept of "static roles", which are
a 1-to-1 mapping of Vault Roles to IAM users. The current password
for the user is stored and automatically rotated by Vault on a
configurable period of time. This is in contrast to dynamic secrets, where a
unique username and password pair are generated with each credential request.
When credentials are requested for the Role, Vault returns the current
Access Key ID and Secret Access Key for the configured user, allowing anyone with the proper
Vault policies to have access to the IAM credentials.
Please see the [API documentation](/vault/api-docs/secret/aws#create-static-role) for details on this feature.
## Setup
Most secrets engines must be configured in advance before they can perform their
functions. These steps are usually completed by an operator or configuration
management tool.
1. Enable the AWS secrets engine:
```text
$ vault secrets enable aws
Success! Enabled the aws secrets engine at: aws/
```
By default, the secrets engine will mount at the name of the engine. To
enable the secrets engine at a different path, use the `-path` argument.
1. Configure the credentials that Vault uses to communicate with AWS to generate
the IAM credentials:
```text
$ vault write aws/config/root \
access_key=AKIAJWVN5Z4FOFT7NLNA \
secret_key=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 \
region=us-east-1
```
Internally, Vault will connect to AWS using these credentials. As such,
these credentials must be a superset of any policies which might be granted
on IAM credentials. Since Vault uses the official AWS SDK, it will use the
specified credentials. You can also specify the credentials via the standard
AWS environment credentials, shared file credentials, or IAM role/ECS task
credentials. (Note that you can't authorize vault with IAM role credentials if you plan
on using STS Federation Tokens, since the temporary security credentials
associated with the role are not authorized to use GetFederationToken.)
In some cases, you cannot set sensitive IAM security credentials in your
Vault configuration. For example, your organization may require that all
security credentials are short-lived or explicitly tied to a machine identity.
To provide IAM security credentials to Vault, we recommend using Vault
[plugin workload identity federation](#plugin-workload-identity-federation-wif)
(WIF).
~> **Notice:** Even though the path above is `aws/config/root`, do not use
your AWS root account credentials. Instead, generate a dedicated user or
role.
1. Alternatively, configure the audience claim value and the role ARN to assume for plugin workload identity federation:
```text
$ vault write aws/config/root \
identity_token_audience="<TOKEN AUDIENCE>" \
role_arn="<AWS ROLE ARN>"
```
Vault's identity token provider will internally sign the plugin identity token JWT.
Given a trust relationship is configured between Vault and AWS via
Web Identity Federation, the secrets engine can exchange this identity token to obtain
ephemeral STS credentials.
~> **Notice:** For this trust relationship to be established, AWS must have an
an [IAM OIDC identity provider](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_providers_create_oidc.html)
configured with information about the fully qualified and network-reachable
Issuer URL for Vault's plugin [identity token provider](/vault/api-docs/secret/identity/tokens#read-plugin-identity-well-known-configurations).
This is to ensure that AWS can fetch the JWKS [public keys](/vault/api-docs/secret/identity/tokens#read-active-public-keys)
and verify the plugin identity token signature. To configure Vault's Issuer,
please refer to the Identity Tokens
[documentation](/vault/api-docs/secret/identity/tokens#configure-the-identity-tokens-backend)
1. Configure a Vault role that maps to a set of permissions in AWS as well as an
AWS credential type. When users generate credentials, they are generated
against this role. An example:
```text
$ vault write aws/roles/my-role \
credential_type=iam_user \
policy_document=-<<EOF
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": "ec2:*",
"Resource": "*"
}
]
}
EOF
```
This creates a role named "my-role". When users generate credentials against
this role, Vault will create an IAM user and attach the specified policy
document to the IAM user. Vault will then create an access key and secret
key for the IAM user and return these credentials. You supply a
user inline policy and/or provide references to an existing AWS policy's full
ARN and/or a list of IAM groups:
```text
$ vault write aws/roles/my-other-role \
policy_arns=arn:aws:iam::aws:policy/AmazonEC2ReadOnlyAccess,arn:aws:iam::aws:policy/IAMReadOnlyAccess \
iam_groups=group1,group2 \
credential_type=iam_user \
policy_document=-<<EOF
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": "ec2:*",
"Resource": "*"
}
]
}
EOF
```
For more information on IAM policies, please see the
[AWS IAM policy documentation](https://docs.aws.amazon.com/IAM/latest/UserGuide/PoliciesOverview.html).
## Usage
After the secrets engine is configured and a user/machine has a Vault token with
the proper permission, it can generate credentials.
1. Generate a new credential by reading from the `/creds` endpoint with the name
of the role:
```text
$ vault read aws/creds/my-role
Key Value
--- -----
lease_id aws/creds/my-role/f3e92392-7d9c-09c8-c921-575d62fe80d8
lease_duration 768h
lease_renewable true
access_key AKIAIOWQXTLW36DV7IEA
secret_key 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
session_token <nil>
```
Each invocation of the command will generate a new credential.
Unfortunately, IAM credentials are eventually consistent with respect to
other Amazon services. If you are planning on using these credential in a
pipeline, you may need to add a delay of 5-10 seconds (or more) after
fetching credentials before they can be used successfully.
If you want to be able to use credentials without the wait, consider using
the STS method of fetching keys. IAM credentials supported by an STS token
are available for use as soon as they are generated.
1. Rotate the credentials that Vault uses to communicate with AWS:
```text
$ vault write -f aws/config/rotate-root
Key Value
--- -----
access_key AKIA3ALIVABCDG5XC8H4
```
<Note>
Calls from Vault to AWS may fail immediately after calling `aws/config/rotate-root` until
AWS becomes consistent again. Refer to
the <a href="/vault/api-docs/secret/aws#rotate-root-iam-credentials">AWS secrets engine API</a> reference
for additional information on rotating IAM credentials.
</Note>
## IAM permissions policy for Vault
The `aws/config/root` credentials need permission to manage dynamic IAM users.
Here is an example AWS IAM policy that grants the most commonly required
permissions Vault needs:
```json
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"iam:AttachUserPolicy",
"iam:CreateAccessKey",
"iam:CreateUser",
"iam:DeleteAccessKey",
"iam:DeleteUser",
"iam:DeleteUserPolicy",
"iam:DetachUserPolicy",
"iam:GetUser",
"iam:ListAccessKeys",
"iam:ListAttachedUserPolicies",
"iam:ListGroupsForUser",
"iam:ListUserPolicies",
"iam:PutUserPolicy",
"iam:AddUserToGroup",
"iam:RemoveUserFromGroup",
"iam:TagUser"
],
"Resource": ["arn:aws:iam::ACCOUNT-ID-WITHOUT-HYPHENS:user/vault-*"]
}
]
}
```
Vault also supports AWS Permissions Boundaries when creating IAM users. If you
wish to enforce that Vault always attaches a permissions boundary to an IAM
user, you can use a policy like:
```json
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"iam:CreateAccessKey",
"iam:DeleteAccessKey",
"iam:DeleteUser",
"iam:ListAccessKeys",
"iam:ListAttachedUserPolicies",
"iam:ListGroupsForUser",
"iam:ListUserPolicies",
"iam:AddUserToGroup",
"iam:RemoveUserFromGroup"
],
"Resource": ["arn:aws:iam::ACCOUNT-ID-WITHOUT-HYPHENS:user/vault-*"]
},
{
"Effect": "Allow",
"Action": [
"iam:AttachUserPolicy",
"iam:CreateUser",
"iam:DeleteUserPolicy",
"iam:DetachUserPolicy",
"iam:PutUserPolicy"
],
"Resource": ["arn:aws:iam::ACCOUNT-ID-WITHOUT-HYPHENS:user/vault-*"],
"Condition": {
"StringEquals": {
"iam:PermissionsBoundary": [
"arn:aws:iam::ACCOUNT-ID-WITHOUT-HYPHENS:policy/PolicyName"
]
}
}
}
]
}
```
where the "iam:PermissionsBoundary" condition contains the list of permissions
boundary policies that you wish to ensure that Vault uses. This policy will
ensure that Vault uses one of the permissions boundaries specified (not all of
them).
## Plugin Workload Identity Federation (WIF)
<EnterpriseAlert product="vault" />
The AWS secrets engine supports the Plugin WIF workflow, and has a source of identity called
a plugin identity token. The plugin identity token is a JWT that is internally signed by Vault's
[plugin identity token issuer](/vault/api-docs/secret/identity/tokens#read-plugin-workload-identity-issuer-s-openid-configuration).
If there is a trust relationship configured between Vault and AWS through
[Web Identity Federation](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_providers_oidc.html),
the secrets engine can exchange its identity token for short-lived STS credentials needed to
perform its actions.
Exchanging identity tokens for STS credentials lets the AWS secrets engine
operate without configuring explicit access to sensitive IAM security
credentials.
To configure the secrets engine to use plugin WIF:
1. Ensure that Vault [openid-configuration](/vault/api-docs/secret/identity/tokens#read-plugin-identity-token-issuer-s-openid-configuration)
and [public JWKS](/vault/api-docs/secret/identity/tokens#read-plugin-identity-token-issuer-s-public-jwks)
APIs are network-reachable by AWS. We recommend using an API proxy or gateway
if you need to limit Vault API exposure.
1. Create an
[IAM OIDC identity provider](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_providers_create_oidc.html)
in AWS.
1. The provider URL **must** point at your [Vault plugin identity token issuer](/vault/api-docs/secret/identity/tokens#read-plugin-workload-identity-issuer-s-openid-configuration) with the
`/.well-known/openid-configuration` suffix removed. For example:
`https://host:port/v1/identity/oidc/plugins`.
1. The audience should uniquely identify the recipient of the plugin identity
token. In AWS, the recipient is the identity provider. We recommend using
the `host:port/v1/identity/oidc/plugins` portion of the provider URL as your
recipient since it will be unique for each configured identity provider.
1. Create a [web identity role](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_create_for-idp_oidc.html#idp_oidc_Create)
in AWS with the same audience used for your IAM OIDC identity provider.
1. Configure the AWS secrets engine with the IAM OIDC audience value and web
identity role ARN.
```shell-session
$ vault write aws/config/root \
identity_token_audience="vault.example/v1/identity/oidc/plugins" \
role_arn="arn:aws:iam::123456789123:role/example-web-identity-role"
```
Your secrets engine can now use plugin WIF for its configuration credentials.
By default, WIF [credentials](https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRoleWithWebIdentity.html)
have a time-to-live of 1 hour and automatically refresh when they expire.
Please see the [API documentation](/vault/api-docs/secret/aws#configure-root-credentials)
for more details on the fields associated with plugin WIF.
## STS credentials
The above demonstrated usage with `iam_user` credential types. As mentioned,
Vault also supports `assumed_role`, `federation_token`, and `session_token`
credential types.
### STS federation tokens
~> **Notice:** Due to limitations in AWS, in order to use the `federation_token`
credential type, Vault **must** be configured with IAM user credentials. AWS
does not allow temporary credentials (such as those from an IAM instance
profile) to be used.
An STS federation token inherits a set of permissions that are the combination
(intersection) of four sets of permissions:
1. The permissions granted to the `aws/config/root` credentials
2. The user inline policy configured in the Vault role
3. The managed policy ARNs configured in the Vault role
4. An implicit deny policy on IAM or STS operations.
Roles with a `credential_type` of `federation_token` can specify one or more of
the `policy_document`, `policy_arns`, and `iam_groups` parameters in the Vault
role.
The `aws/config/root` credentials require IAM permissions for
`sts:GetFederationToken` and the permissions to delegate to the STS
federation token. For example, this policy on the `aws/config/root` credentials
would allow creation of an STS federated token with delegated `ec2:*`
permissions (or any subset of `ec2:*` permissions):
```javascript
{
"Version": "2012-10-17",
"Statement": {
"Effect": "Allow",
"Action": [
"ec2:*",
"sts:GetFederationToken"
],
"Resource": "*"
}
}
```
An `ec2_admin` role would then assign an inline policy with the same `ec2:*`
permissions.
```shell-session
$ vault write aws/roles/ec2_admin \
credential_type=federation_token \
policy_document=@policy.json
```
The policy.json file would contain an inline policy with similar permissions,
less the `sts:GetFederationToken` permission. (We could grant
`sts:GetFederationToken` permissions, but STS attaches attach an implicit deny
that overrides the allow.)
```javascript
{
"Version": "2012-10-17",
"Statement": {
"Effect": "Allow",
"Action": "ec2:*",
"Resource": "*"
}
}
```
To generate a new set of STS federation token credentials, we simply write to
the role using the aws/sts endpoint:
```shell-session
$ vault write aws/sts/ec2_admin ttl=60m
Key Value
lease_id aws/sts/ec2_admin/31d771a6-fb39-f46b-fdc5-945109106422
lease_duration 60m0s
lease_renewable false
access_key ASIAJYYYY2AA5K4WIXXX
secret_key HSs0DYYYYYY9W81DXtI0K7X84H+OVZXK5BXXXX
session_token AQoDYXdzEEwasAKwQyZUtZaCjVNDiXXXXXXXXgUgBBVUUbSyujLjsw6jYzboOQ89vUVIehUw/9MreAifXFmfdbjTr3g6zc0me9M+dB95DyhetFItX5QThw0lEsVQWSiIeIotGmg7mjT1//e7CJc4LpxbW707loFX1TYD1ilNnblEsIBKGlRNXZ+QJdguY4VkzXxv2urxIH0Sl14xtqsRPboV7eYruSEZlAuP3FLmqFbmA0AFPCT37cLf/vUHinSbvw49C4c9WQLH7CeFPhDub7/rub/QU/lCjjJ43IqIRo9jYgcEvvdRkQSt70zO8moGCc7pFvmL7XGhISegQpEzudErTE/PdhjlGpAKGR3d5qKrHpPYK/k480wk1Ai/t1dTa/8/3jUYTUeIkaJpNBnupQt7qoaXXXXXXXXXX
```
### STS Session Tokens
The `session_token` credential type is used to generate short-lived credentials under the root config.
To create these with Vault and AWS, you must configure Vault to use IAM user credentials. AWS does not
allow temporary credentials, like those from an IAM instance profile, to be used when generating session tokens.
<Warning>
STS session tokens inherit any and all permissions granted to the user configured in `aws/config/root`.
In this expample, the `temp_user` role will obtain a policy with the same `ec2:*` permissions as the
root config. For this reason, assigning a role or policy is disallowed for this credential type.
</Warning>
```shell-session
$ vault write aws/roles/temp_user \
credential_type=session_token
```
To generate a new set of STS federation token credentials, write to the `temp_user`
role using the `aws/creds` endpoint:
```shell-session
$ vault read aws/sts/temp_user ttl=60m
Key Value
lease_id aws/creds/temp_user/w4eKbMaJOi1xLqG3MWk7y8n6
lease_duration 60m0s
lease_renewable false
access_key ASIAJYYYY2AA5K4WIXXX
secret_key HSs0DYYYYYY9W81DXtI0K7X84H+OVZXK5BXXXX
session_token AQoDYXdzEEwasAKwQyZUtZaCjVNDiXXXXXXXXgUgBBVUUbSyujLjsw6jYzboOQ89vUVIehUw/9MreAifXFmfdbjTr3g6zc0me9M+dB95DyhetFItX5QThw0lEsVQWSiIeIotGmg7mjT1//e7CJc4LpxbW707loFX1TYD1ilNnblEsIBKGlRNXZ+QJdguY4VkzXxv2urxIH0Sl14xtqsRPboV7eYruSEZlAuP3FLmqFbmA0AFPCT37cLf/vUHinSbvw49C4c9WQLH7CeFPhDub7/rub/QU/lCjjJ43IqIRo9jYgcEvvdRkQSt70zO8moGCc7pFvmL7XGhISegQpEzudErTE/PdhjlGpAKGR3d5qKrHpPYK/k480wk1Ai/t1dTa/8/3jUYTUeIkaJpNBnupQt7qoaXXXXXXXXXX
```
Session tokens may also require an MFA-based TOTP to be provided if the IAM user is configured to require it.
If so, the Vault role requires the MFA device serial number to be set, and the TOTP may be provided when
reading credentials from the Vault role.
```shell-session
$ vault write aws/roles/mfa_user \
credential_type=session_token \
mfa_serial_number="arn:aws:iam::ACCOUNT-ID-WITHOUT-HYPHENS:mfa/device-name"
```
```shell-session
$ vault read aws/creds/mfa_user mfa_code=123456
```
### STS AssumeRole
The `assumed_role` credential type is typically used for cross-account
authentication or single sign-on (SSO) scenarios. In order to use an
`assumed_role` credential type, you must configure outside of Vault:
1. An IAM role
2. IAM inline policies and/or managed policies attached to the IAM role
3. IAM trust policy attached to the IAM role to grant privileges for Vault to
assume the role
`assumed_role` credentials offer a few benefits over `federation_token`:
1. Assumed roles can invoke IAM and STS operations, if granted by the role's
IAM policies.
2. Assumed roles support cross-account authentication
3. Temporary credentials (such as those granted by running Vault on an EC2
instance in an IAM instance profile) can retrieve `assumed_role` credentials
(but cannot retrieve `federation_token` credentials).
The `aws/config/root` credentials must be allowed `sts:AssumeRole` through one of
two methods:
1. The credentials have an IAM policy attached to them against the target role:
```javascript
{
"Version": "2012-10-17",
"Statement": {
"Effect": "Allow",
"Action": "sts:AssumeRole",
"Resource": "arn:aws:iam::ACCOUNT-ID-WITHOUT-HYPHENS:role/RoleNameToAssume"
}
}
```
1. A trust policy is attached to the target IAM role for the principal:
```javascript
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Principal": {
"AWS": "arn:aws:iam::ACCOUNT-ID-WITHOUT-HYPHENS:user/VAULT-AWS-ROOT-CONFIG-USER-NAME"
},
"Action": "sts:AssumeRole"
}
]
}
```
When specifying a Vault role with a `credential_type` of `assumed_role`, you can
specify more than one IAM role ARN. If you do so, Vault clients can select which
role ARN they would like to assume when retrieving credentials from that role.
Further, you can specify both a `policy_document` and `policy_arns` parameters;
if specified, each acts as a filter on the IAM permissions granted to the
assumed role. If `iam_groups` is specified, the inline and attached policies for
each IAM group will be added to the `policy_document` and `policy_arns`
parameters, respectively, when calling [sts:AssumeRole]. For an action to be
allowed, it must be permitted by both the IAM policy on the AWS role that is
assumed, the `policy_document` specified on the Vault role (if specified), and
the managed policies specified by the `policy_arns` parameter. (The
`policy_document` parameter is passed in as the `Policy` parameter to the
[sts:AssumeRole] API call, while the `policy_arns` parameter is passed in as the
`PolicyArns` parameter to the same call.)
Note: When multiple `role_arns` are specified, clients requesting credentials
can specify any of the role ARNs that are defined on the Vault role in order to
retrieve credentials. However, when `policy_document`, `policy_arns`, or
`iam_groups` are specified, that will apply to ALL role credentials retrieved
from AWS.
Let's create a "deploy" policy using the arn of our role to assume:
```shell-session
$ vault write aws/roles/deploy \
role_arns=arn:aws:iam::ACCOUNT-ID-WITHOUT-HYPHENS:role/RoleNameToAssume \
credential_type=assumed_role
```
To generate a new set of STS assumed role credentials, we again write to
the role using the aws/sts endpoint:
```shell-session
$ vault write aws/sts/deploy ttl=60m
Key Value
lease_id aws/sts/deploy/31d771a6-fb39-f46b-fdc5-945109106422
lease_duration 60m0s
lease_renewable false
access_key ASIAJYYYY2AA5K4WIXXX
secret_key HSs0DYYYYYY9W81DXtI0K7X84H+OVZXK5BXXXX
session_token AQoDYXdzEEwasAKwQyZUtZaCjVNDiXXXXXXXXgUgBBVUUbSyujLjsw6jYzboOQ89vUVIehUw/9MreAifXFmfdbjTr3g6zc0me9M+dB95DyhetFItX5QThw0lEsVQWSiIeIotGmg7mjT1//e7CJc4LpxbW707loFX1TYD1ilNnblEsIBKGlRNXZ+QJdguY4VkzXxv2urxIH0Sl14xtqsRPboV7eYruSEZlAuP3FLmqFbmA0AFPCT37cLf/vUHinSbvw49C4c9WQLH7CeFPhDub7/rub/QU/lCjjJ43IqIRo9jYgcEvvdRkQSt70zO8moGCc7pFvmL7XGhISegQpEzudErTE/PdhjlGpAKGR3d5qKrHpPYK/k480wk1Ai/t1dTa/8/3jUYTUeIkaJpNBnupQt7qoaXXXXXXXXXX
```
[sts:assumerole]: https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html
## Troubleshooting
### Dynamic IAM user errors
If you get an error message similar to either of the following, the root credentials that you wrote to `aws/config/root` have insufficient privilege:
```shell-session
$ vault read aws/creds/deploy
* Error creating IAM user: User: arn:aws:iam::000000000000:user/hashicorp is not authorized to perform: iam:CreateUser on resource: arn:aws:iam::000000000000:user/vault-root-1432735386-4059
$ vault revoke aws/creds/deploy/774cfb27-c22d-6e78-0077-254879d1af3c
Revoke error: Error making API request.
URL: POST http://127.0.0.1:8200/v1/sys/revoke/aws/creds/deploy/774cfb27-c22d-6e78-0077-254879d1af3c
Code: 400. Errors:
* invalid request
```
If you get stuck at any time, simply run `vault path-help aws` or with a subpath for
interactive help output.
### STS federated token errors
Vault generates STS tokens using the IAM credentials passed to `aws/config`.
Those credentials must have two properties:
- They must have permissions to call `sts:GetFederationToken`.
- The capabilities of those credentials have to be at least as permissive as those requested
by policies attached to the STS creds.
If either of those conditions are not met, a "403 not-authorized" error will be returned.
See http://docs.aws.amazon.com/STS/latest/APIReference/API_GetFederationToken.html for more details.
Vault 0.5.1 or later is recommended when using STS tokens to avoid validation
errors for exceeding the AWS limit of 32 characters on STS token names.
<Note title="AWS character limit includes path">
The AWS character limit for token names **includes** the full path to
the token. For example, `aws/sts/dev005_vault-test_testtest` (34
characters) exceeds the limit , but `aws/roles/dev005_vaulttest-test` (31
characters) does not.
</Note>
### AWS instance metadata timeouts
@include 'aws-imds-timeout.mdx'
## API
The AWS secrets engine has a full HTTP API. Please see the
[AWS secrets engine API](/vault/api-docs/secret/aws) for more
details.