Gates bucket listing behind an identity policy, lets browsers reach the standalone IAM API, and turns the WebUI into a dashboard for S3, IAM, or both.
**Bucket listing.** `ListBuckets` is now gated by the new `s3:ListAllMyBuckets` action, evaluated against `arn:aws:s3:::*`. The request names no bucket, so only identity policies apply — there is no resource policy to combine with, which is the same shape `CreateBucket` already had, so both now share one identity-only evaluation path. Root and admin bypass it, and backends with no identity-policy layer keep listing as before since their listing is already narrowed to the caller's own buckets. The action is IAM-only and is deliberately absent from the bucket-policy action list.
**Fixed bucket ownership.** The standalone IAM client has no per-user ownership to express — accounts are all plain users, cannot be enumerated, and access is decided by policy rather than ACL — so it now implements `auth.FixedBucketOwner` and every bucket is owned by root. Bucket creation stops resolving an owner, `ListBuckets` returns every bucket to every caller (what they may then do with one stays a per-request policy decision), and the admin `ChangeBucketOwner` reports method-not-supported. Other IAM backends are untouched.
**IAM service CORS.** `--cors-allow-origin` now applies to the `iam` command: it answers preflights and stamps the CORS headers, mirroring back the requested method and headers rather than enumerating the SigV4 header set. Without it no browser can reach the IAM API at all, so setting `--webui` without it falls back to `*` with a warning. The chart gets `iamServer.corsAllowOrigin`.
**WebUI.** New IAM pages for users, roles and OIDC providers, signing IAM/STS query-form requests directly from the browser. Navigation is capability-gated rather than role-gated: on sign-in the session probes the S3, admin and IAM endpoints independently and each page shows only what those credentials actually reach, so one build serves an IAM-only dashboard, an S3-only dashboard, and a combined one. The login page takes an optional IAM endpoint, seeded from the new `--webui-iam-gateways` (chart: `webui.iamGateways`) — never auto-detected, since the IAM service is a separate process. The WebUI can also be hosted by `versitygw iam` itself, for deployments with no S3 gateway behind it.
**The admin API is ignored once an IAM endpoint is in play.** The IAM service is then the user directory and bucket ownership is fixed, which leaves the admin API no job: the session is given no admin endpoint at all, its login field is hidden, `users.html` redirects to its IAM counterpart, and every admin-only surface stays off screen. Dashboard and Buckets remain available to any S3 session in such a deployment, running on the S3 and IAM APIs alone and surfacing each denial per action instead of redirecting.
Also fixes two WebUI bugs: embedded assets went out with a zero modification time and no `Cache-Control`, so browsers treated them as fresh for centuries and an upgraded gateway served new HTML against stale JS — they now revalidate against an ETag; and the login page's advanced-options section clipped its last field, since it animated to a height named in the stylesheet rather than the one it measures now.
**Usage**
IAM-only dashboard, served by the IAM service:
versitygw iam --port :7076 --webui :8080 --cors-allow-origin http://localhost:8080/
IAM + S3, dashboard served by the IAM service — point it at the gateway with `--webui-gateways`, and let the gateway accept the dashboard's origin:
versitygw iam --port :7076 --webui :8080 --webui-gateways http://localhost:7070/ --cors-allow-origin http://localhost:8080/
versitygw --port :7070 --cors-allow-origin http://localhost:8080/ posix /data
IAM + S3, dashboard served by the S3 gateway — point it at the IAM service with `--webui-iam-gateways`, and let the IAM service accept the dashboard's origin:
versitygw --port :7070 --webui :8080 --webui-iam-gateways http://localhost:7076/ posix /data
versitygw iam --port :7076 --cors-allow-origin http://localhost:8080/
Fixes#1327Fixes#1567Closes#2264
Wires the S3 gateway up to the standalone IAM service so identity policies, not just bucket policies and ACLs, are enforced on the S3 data plane. The gateway authenticates SigV4 requests by calling new private derive-signing-key and resolve-identity endpoints on the IAM service instead of holding secrets itself, and evaluates identity policy through the same PolicyEvaluator path added to auth.VerifyAccess, combined with the bucket policy using explicit-deny-wins precedence. The private endpoints are served over their own mTLS listener (new iamapi/private package, genmtlscerts.sh to generate test material, and client-cert support in internal/netutil), separate from the public IAM API. As part of this the vendored aws/signer/v4 package is deleted and replaced by a pure-Go SigV4 implementation in internal/sigv4auth, which now reads canonical request data directly off the fiber.Ctx instead of reconstructing an http.Request, and is shared by both the S3 request-signing verification and the new private-endpoint signing.
DeleteObjects moves from an all-or-nothing authorization check to true partial success: VerifyObjectsAccess evaluates every object in a batch independently against both the identity policy and any object lock, so a denial or a locked object only removes that key from the batch instead of failing the whole request. It also batches the identity-policy round trip and the bucket-policy fetch once per request rather than once per object, and separates plain deletes from versioned ones since a versioned delete needs s3:DeleteObjectVersion rather than s3:DeleteObject. Object lock handling got a few correctness fixes alongside this: a bypass is now modeled as BypassNone/BypassRequested/BypassOverwrite rather than a single bool, because root's blanket ability to override a GOVERNANCE retention should only apply when the client actually asked to bypass it (DeleteObject/DeleteObjects/PutObjectRetention), not when the gateway is silently replacing a locked object via an overwrite, which needs the permission from everyone including root. Retention changes are now correctly classified as an extension (allowed under plain s3:PutObjectRetention) versus a weakening (date or mode change, which needs the bypass permission), and a COMPLIANCE lock can never be weakened by anyone regardless of permissions, matching AWS. Separately, VerifyObjectCopyAccess had a readonly-mode gap: it returned early for root/admin before ever calling VerifyAccess, so the readonly check inside VerifyAccess never ran for them on CopyObject; access checks are now ordered so the readonly gate always applies before any root/admin bypass, for copy as well as every other write path.
Bucket policies also gained Condition block support, via a new shared internal/condition package moved out of the IAM policy package since both bucket and identity policies share the same evaluation semantics. It implements the full AWS operator set — String{Equals,NotEquals,EqualsIgnoreCase,NotEqualsIgnoreCase,Like,NotLike}, Numeric{Equals,NotEquals,LessThan,LessThanEquals,GreaterThan,GreaterThanEquals}, Date{Equals,NotEquals,LessThan,LessThanEquals,GreaterThan,GreaterThanEquals}, Bool, BinaryEquals, Arn{Equals,Like,NotEquals,NotLike}, IpAddress/NotIpAddress, and Null — along with the ForAllValues/ForAnyValue set qualifiers and the IfExists modifier. A new requestConditionContext builds the per-request keys a bucket policy's Condition block can reference — aws:SourceIp, aws:SecureTransport, aws:CurrentTime, aws:EpochTime, aws:UserAgent, aws:Referer, s3:prefix, s3:delimiter, s3:max-keys, s3:x-amz-acl, s3:VersionId — following AWS's own per-action rules for which keys a given S3 operation actually populates. Identity-derived keys such as aws:PrincipalArn and aws:username are deliberately left unwired here, since the gateway has no way to know them; the standalone IAM service fills those in itself when it evaluates an identity policy.
Also added new integration test suites for S3-side IAM: s3_iam_access_control.go and s3_iam_session_access_control.go cover identity-policy enforcement and session-credential requests against real S3 operations, alongside expanded OIDC/web-identity coverage and a new runoidctests.sh runner wired into the OIDC GitHub Actions workflow.
Object key validation allowed internal parent-directory segments such as `public/../private.txt`. Bucket policy and auth checks evaluated the raw key, so a policy allowing bucket/public/* could match the request while posix backend later resolved the key with `filepath.Join` and accessed `bucket/private.txt`.
Add backend-specific object key normalization to close that mismatch. The Backend interface now exposes `NormalizeObjectKey` so authorization can evaluate resources using the same key shape a backend will use for storage access.
Backends that do not collapse object paths, including Azure and the S3 proxy, inherit `BackendUnsupported.NormalizeObjectKey`. That implementation returns the input key unchanged, avoiding unnecessary normalization and keeping policy evaluation unpolluted for object stores where ../ is part of the key name.
posix/scoutfs normalize keys with filepath.Join so policy resources and request keys are compared after internal dot segments are collapsed.
Bucket policy evaluation now normalizes both the incoming object key and object resource patterns from the policy before matching. Object lock governance bypass policy checks use the same backend normalizer as well, so retention and legal hold authorization cannot diverge from backend path resolution.
Distinguish public bucket policy no-match from explicit deny during anonymous access checks. This preserves ACL fallback only for requests that are not allowed by policy, while ensuring a matching Deny statement short-circuits authorization and returns AccessDenied even when a public ACL would otherwise grant access.
Fixes#2123Fixes#2120Fixes#2116Fixes#2111Fixes#2108Fixes#2086Fixes#2085Fixes#2083Fixes#2081Fixes#2080Fixes#2073Fixes#2072Fixes#2071Fixes#2069Fixes#2044Fixes#2043Fixes#2042Fixes#2041Fixes#2040Fixes#2039Fixes#2036Fixes#2035Fixes#2034Fixes#2028Fixes#2020Fixes#1842Fixes#1810Fixes#1780Fixes#1775Fixes#1736Fixes#1705Fixes#1663Fixes#1645Fixes#1583Fixes#1526Fixes#1514Fixes#1493Fixes#1487Fixes#959Fixes#779Closes#823Closes#85
Refactor global S3 error handling around structured error types and centralized XML response generation.
All S3 errors now share the common APIError base for the fields every error has: Code, HTTP status code, and Message. Non-traditional errors that need AWS-compatible XML fields now have dedicated typed errors in the s3err package. Each typed error implements the shared S3Error behavior so controllers and middleware can handle errors consistently while still emitting error-specific XML fields.
Add a dedicated InvalidArgumentError type because InvalidArgument is used widely across request validation, auth, copy source handling, object lock validation, multipart validation, and header parsing. The new InvalidArgument path uses explicit InvalidArgErrorCode constants with predefined descriptions and ArgumentName values, keeping call sites readable while preserving the correct InvalidArgument XML shape and optional ArgumentValue.
New structured errors added in s3err:
- `AccessForbiddenError`: Method, ResourceType
- `BadDigestError`: CalculatedDigest, ExpectedDigest
- `BucketError`: BucketName
- `ContentSHA256MismatchError`: ClientComputedContentSHA256, S3ComputedContentSHA256
- `EntityTooLargeError`: ProposedSize, MaxSizeAllowed
- `EntityTooSmallError`: ProposedSize, MinSizeAllowed
- `ExpiredPresignedURLError`: ServerTime, XAmzExpires, Expires
- `InvalidAccessKeyIdError`: AWSAccessKeyId
- `InvalidArgumentError`: Description, ArgumentName, ArgumentValue
- `InvalidChunkSizeError`: Chunk, BadChunkSize
- `InvalidDigestError`: ContentMD5
- `InvalidLocationConstraintError`: LocationConstraint
- `InvalidPartError`: UploadId, PartNumber, ETag
- `InvalidRangeError`: RangeRequested, ActualObjectSize
- `InvalidTagError`: TagKey, TagValue
- `KeyTooLongError`: Size, MaxSizeAllowed
- `MetadataTooLargeError`: Size, MaxSizeAllowed
- `MethodNotAllowedError`: Method, ResourceType, AllowedMethods
- `NoSuchUploadError`: UploadId
- `NoSuchVersionError`: Key, VersionId
- `NotImplementedError`: Header, AdditionalMessage
- `PreconditionFailedError`: Condition
- `RequestTimeTooSkewedError`: RequestTime, ServerTime, MaxAllowedSkewMilliseconds
- `SignatureDoesNotMatchError`: AWSAccessKeyId, StringToSign, SignatureProvided, StringToSignBytes, CanonicalRequest, CanonicalRequestBytes
Fix CompleteMultipartUpload validation in the Azure backend so missing or empty `ETag` values return the appropriate S3 error instead of allowing a gateway panic.
Fix presigned authentication expiration validation to compare server time in `UTC`, matching the `UTC` timestamp used by presigned URL signing.
Add request ID and host ID support across S3 requests. Each request now receives AWS S3-like identifiers, returned in response headers as `x-amz-request-id` and `x-amz-id-2` and included in all XML error responses as RequestId and HostId. The generated ID structure is designed to resemble AWS S3 request IDs and host IDs.
The request signature calculation/validation for streaming uploads was previously delayed until the request body was fully read, both for Authorization header authentication and presigned URLs.
Now, the signature is validated immediately in the authorization middlewares without reading the request body, since the signature calculation itself does not depend on the request body. Instead, only the `x-amz-content-sha256` SHA-256 hash calculation is delayed.
Fixes#1986
When a client includes tagging, legal hold, or retention headers in a PutObject, CopyObject or CreateMultipartUpload request, the corresponding bucket policy permissions must be verified in addition to s3:PutObject:
`X-Amz-Tagging` - `s3:PutObjectTagging`
`X-Amz-Object-Lock-Legal-Hold` - `s3:PutObjectLegalHold`
`X-Amz-Object-Lock-Mode` - `s3:PutObjectRetention`
Previously, only s3:PutObject was checked, allowing users to set tagging, legal hold, and retention without having the required permissions. Now each action permission is check, if user tries to add them.
For CopyObject these permissions are checked on destination object.
Closes#1847
This PR introduces a global optional gateway CLI flag `--disable-acl` (`VGW_DISABLE_ACL`) to disable ACL handling. When this flag is enabled, the gateway ignores all ACL-related headers, particularly in `CreateBucket`, `PutObject`, `CopyObject`, and `CreateMultipartUpload`.
`GetBucketAcl` behavior is unchanged simply returning the bucket ACL config.
There's no change in object ACL actions(`PutObjectACL`, `GetObjectACL`). They return a`NotImplemented` error as before.
A new custom error is added for PutBucketAcl calls when ACLs are disabled at the gateway level. Its HTTP status code and error code match AWS S3’s behavior, with only a slightly different error message.
In the access-control checker, ACL evaluation is fully bypassed. If ACLs are disabled only the bucket owner gets access to the bucket and all grantee checks are ignored.
The PR also includes minor refactoring of the S3 API server and router. The growing list of parameters passed to the router’s Init method has been consolidated into fields within the router struct, initialized during router construction. Parameters not needed by the S3 server are no longer stored in the server configuration and are instead forwarded directly to the router.
Fixes#1765Fixes#1771
This PR addresses two issues:
1. CreateBucket was previously allowed when the gateway was running in read-only mode. It is now correctly blocked.
2. Write operations were permitted on public buckets in read-only mode because the public access checks in `auth.VerifyAccess` were evaluated before the read-only check. The read-only check now takes precedence, and all write operations on public buckets are blocked.
GetObject allows overriding response headers with the following
paramters:
response-cache-control
response-content-disposition
response-content-encoding
response-content-language
response-content-type
response-expires
This is only valid for signed (and pre-singed) requests. An error
is returned for anonymous requests if these are set.
More info on the GetObject overrides can be found in the GetObject
API reference.
This also clarifies the naming of the AccessOptions IsPublicBucket
to IsPublicRequest to indicate this is a public access request
and not just accessing a bucket that allows public access.
Fixes#1501
Fixes#1388Fixes#1389Fixes#1390Fixes#1401
Adds the `x-amz-copy-source` header validation for `CopyObject` and `UploadPartCopy` in front-end.
The error:
```
ErrInvalidCopySource: {
Code: "InvalidArgument",
Description: "Copy Source must mention the source bucket and key: sourcebucket/sourcekey.",
HTTPStatusCode: http.StatusBadRequest,
},
```
is now deprecated.
The conditional read/write headers validation in `CopyObject` should come with #821 and #822.
This implementation introduces **public buckets**, which are accessible without signature-based authentication.
There are two ways to grant public access to a bucket:
* **Bucket ACLs**
* **Bucket Policies**
Only `Get` and `List` operations are permitted on public buckets. All **write operations** require authentication, regardless of whether public access is granted through an ACL or a policy.
The implementation includes an `AuthorizePublicBucketAccess` middleware, which checks if public access has been granted to the bucket. If so, authentication middlewares are skipped. For unauthenticated requests, appropriate errors are returned based on the specific S3 action.
---
**1. Bucket-Level Operations:**
```json
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Principal": "*",
"Action": "s3:*",
"Resource": "arn:aws:s3:::test"
}
]
}
```
**2. Object-Level Operations:**
```json
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Principal": "*",
"Action": "s3:*",
"Resource": "arn:aws:s3:::test/*"
}
]
}
```
**3. Both Bucket and Object-Level Operations:**
```json
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Principal": "*",
"Action": "s3:*",
"Resource": "arn:aws:s3:::test"
},
{
"Effect": "Allow",
"Principal": "*",
"Action": "s3:*",
"Resource": "arn:aws:s3:::test/*"
}
]
}
```
---
```sh
aws s3api create-bucket --bucket test --object-ownership BucketOwnerPreferred
aws s3api put-bucket-acl --bucket test --acl public-read
```