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.
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.
Integrate the new S3 checksum types in the gateway, including `SHA512`, `MD5`, `XXHASH64`, `XXHASH3`, and `XXHASH128`. This adds checksum calculation, validation, schema handling, and test coverage for the expanded checksum support.
These external packages have been used:
- `github.com/zeebo/xxh3` for `XXHASH3` and `XXHASH128`
- `github.com/cespare/xxhash/v2` for `XXHASH64`
Adjust integration tests because `aws-sdk-go-v2/service/s3` does not support automatic checksum calculation for the new checksum algorithms and returns an SDK-level error when only the checksum algorithm is provided. Only precalculated checksum values are acceptable for these checksum types.
References:
- `https://github.com/aws/aws-sdk-go-v2/issues/3404`
- `https://github.com/aws/aws-sdk-go-v2/issues/3403`
Closes#1813
We use a specific `versionId` format(`ulid` package) to generate versionIds in posix, which is not compatible to S3. The versionId validation was performed in frontend which is a potential source of failure for s3 proxy configured on an s3 service which doesn't use ulid for versionId generation(e.g. aws S3). These changes move the specific `ulid` versionId validation to posix to not force any specific versionId format in the gateway.
Closes#1648Fixes#1980Fixes#1981
This PR implements browser-based POST object uploads for S3-compatible form uploads. It adds support for handling `multipart/form-data` object uploads submitted from browsers, including streaming multipart parsing so file content is not buffered in memory, POST policy decoding and evaluation, SigV4-based form authorization, and integration with the existing `PutObject` backend flow. The implementation covers the full browser POST upload path, including validation of required form fields, credential scope and request date checks, signature verification, metadata extraction from `x-amz-meta-*` fields, checksum field parsing, object tagging conversion from XML into the query-string format expected by `PutObject`, and browser-compatible success handling through `success_action_status` and `success_action_redirect`. It also wires the new flow into the router and metrics layer and adds POST-specific error handling and debug logging across policy parsing, multipart parsing, and POST authorization. AWS S3 also accepts the `redirect` form field alongside `success_action_redirect`, but since AWS has marked `redirect` as deprecated and is planning to remove it, this gateway intentionally does not support it.
Fixes#1896
Enforces the S3 `5 GiB` copy source size limit across the posix and azure
backends for `CopyObject` and `UploadPartCopy`, returning `InvalidRequest` when
the source object exceeds the threshold.
The limit is now configurable via `--copy-object-threshold`
(`VGW_COPY_OBJECT_THRESHOLD`, default 5 GiB).
A new `--mp-max-parts flag` (`VGW_MP_MAX_PARTS`, default `10000`) has been added to make multipart upload parts number limit configurable.
No integration test has been added, as GitHub Actions cannot reliably
handle large objects.
Fixes#1606
According to AWS documentation:
> *“The PUT request header is limited to 8 KB in size. Within the PUT request header, the user-defined metadata is limited to 2 KB in size. The size of user-defined metadata is measured by taking the sum of the number of bytes in the UTF-8 encoding of each key and value.”*
Based on this, object metadata size is now limited to **2 KB** for all object upload operations (`PutObject`, `CopyObject`, and `CreateMultipartUpload`).
Fixes handling of metadata HTTP headers when the same header appears multiple times with different casing or even if they are identical. According to S3 behavior, these headers must be merged into a single lower-cased metadata key, with values concatenated using commas.
Example:
```
x-amz-meta-Key: value1
x-amz-meta-kEy: value2
x-amz-meta-keY: value3
```
Translated to:
```
key: value1,value2,value3
```
This PR also introduces an **8 KB limit for request headers**. Although the S3 documentation explicitly mentions the 8 KB limit only for **PUT requests**, in practice this limit applies to **all requests**.
To enforce the header size limit, the Fiber configuration option `ReadBufferSize` is used. This parameter defines the maximum number of bytes read when parsing an incoming request. Note that this limit does not apply strictly to request headers only, since request parsing also includes other parts of the request line (e.g., the HTTP method, protocol string, and version such as `HTTP/1.1`). So `ReadBufferSize` is effectively a limit for request headers size, but not the exact limit.
Fixes#1698
`PutObjectTagging`, `GetObjectTagging` and `DeleteObjectTagging` return the `x-amz-version-id` in the response headers. The PR adds this header in the responses.
Fixes#1630
S3 returns `InvalidArgument: Invalid version id specified` for invalid version IDs in object-level actions that accept `versionId` as a query parameter. The `versionId` in S3 follows a specific structure, and if the input string doesn’t match this structure, the error is returned. In the gateway, the `versionId` is generated using the `ulid` package, which also has a defined structure. This PR adds validation for object-level operations that work with object versions by using the ULID parser.
These actions include: `HeadObject`, `GetObject`, `PutObjectTagging`, `GetObjectTagging`, `DeleteObjectTagging`, `PutObjectLegalHold`, `GetObjectLegalHold`, `PutObjectRetention`, `GetObjectRetention`, `DeleteObject`, `CopyObject`, `UploadPartCopy`, and `GetObjectAttributes`.
Closes#1343
Object version tagging support was previously missing in the gateway. The support is added with this PR. If versioning is not enabled at the gateway level and a user attempts to put, get, or delete object version tags, the gateway returns an `InvalidArgument`(Invalid versionId)
Fixes#1242
S3 returns a specific error for actions that expect an empty request body but receive a non-empty one. Such actions include **CopyObject** and **UploadPartCopy**, which are HTTP PUT requests with no request body. This implementation adds a check for these actions and returns the corresponding error.
Closes#1566
When an object is locked and bucket versioning is not configured at the gateway level, any object overwrite request should be rejected with an object locked error. The `PutObject` operation already follows this behavior, but `CopyObject` and `CompleteMultipartUpload` were missing this check. This change introduces the locking mechanism for `CopyObject` and `CompleteMultipartUpload` operations.
Fixes#1574
When versioning is enabled at the gateway level and object lock is enabled for a bucket, any overwrite request on a locked object should succeed since it results in the creation of a new object version. This PR fixes the logic by adding a bucket versioning status check in `CheckObjectAccess`.
Fixes#1559Fixes#1330
This PR focuses on three main changes:
1. **Fix object lock error codes and descriptions**
When an object was WORM-protected and delete/overwrite was disallowed due to object lock configurations, the gateway incorrectly returned the `s3.ErrObjectLocked` error code and description. These have now been corrected.
2. **Update `PutObjectRetention` behavior**
Previously, when an object already had a retention mode set, the gateway only allowed modifications if the mode was changed from `GOVERNANCE` to `COMPLIANCE`, and only when the user had the `s3:BypassGovernanceRetention` permission.
The logic has been updated: if the existing retention mode is the same as the one being applied, the operation is now allowed regardless of other factors.
3. **Fix error checks in integration tests (AWS SDK regression)**
Due to an AWS SDK regression, integration tests were previously limited to checking partial error descriptions. This issue seems to be resolved for some actions (though the ticket is still open: https://github.com/aws/aws-sdk-go-v2/issues/2921). Error checks have been reverted back to full description comparisons where possible.
Closes#821
**Implements conditional operations across object APIs:**
* **PutObject** and **CompleteMultipartUpload**:
Supports conditional writes with `If-Match` and `If-None-Match` headers (ETag comparisons).
Evaluation is based on an existing object with the same key in the bucket. The operation is allowed only if the preconditions are satisfied. If no object exists for the key, these headers are ignored.
* **CopyObject** and **UploadPartCopy**:
Adds conditional reads on the copy source object with the following headers:
* `x-amz-copy-source-if-match`
* `x-amz-copy-source-if-none-match`
* `x-amz-copy-source-if-modified-since`
* `x-amz-copy-source-if-unmodified-since`
The first two are ETag comparisons, while the latter two compare against the copy source’s `LastModified` timestamp.
* **AbortMultipartUpload**:
Supports the `x-amz-if-match-initiated-time` header, which is true only if the multipart upload’s initialization time matches.
* **DeleteObject**:
Adds support for:
* `If-Match` (ETag comparison)
* `x-amz-if-match-last-modified-time` (LastModified comparison)
* `x-amz-if-match-size` (object size comparison)
Additionally, this PR updates precondition date parsing logic to support both **RFC1123** and **RFC3339** formats. Dates set in the future are ignored, matching AWS S3 behavior.
Closes#1518
Adds the `x-amz-object-size` header to the `PutObject` response, indicating the size of the uploaded object. This change is applied to the POSIX, Azure, and S3 proxy backends.
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.
niksis02
Ben McClellandandGitHub