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#2180Fixes#2181
Migrate the gateway from Fiber v2 to Fiber v3.3.0 and update the affected server, middleware, handler, controller, and test code for the new APIs.
Replace the deprecated Fiber filesystem middleware used by the WebUI with the Fiber v3 static middleware, serving the embedded WebUI assets from an fs.Sub filesystem.
Fix the request header limit handling regression by adding a temporary handler for Fiber v3/fasthttp small-buffer errors so oversized request headers return the expected regulated S3 error response.
Fix the debuglogger panic by reworking the boxed key/value formatter used for debug request and response dumps. The formatter now handles long header keys and values without producing invalid wrap widths, negative padding, or out-of-range string slices.
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.
The gateway currently supports only Signature Version 4 (SigV4) authorization. Deprecated AWS SigV2 requests are now rejected with an AWS-specific `InvalidRequest` error for both Authorization-header requests and query-string requests(presigned URLs).
This also fixes SigV4 Authorization-header handling for date headers. SigV4 accepts two date headers: `Date` and `X-Amz-Date`. `X-Amz-Date` takes precedence, but when it is missing, `Date` should be used. The gateway now uses the `Date` header with lower precedence when `X-Amz-Date` is not present. No SDK integration test was added for this case because the SDK always sets `X-Amz-Date`, and this behavior is not configurable.
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.
Closes#1525
* Adds validation for the `Content-MD5` header.
* If the header value is invalid, the gateway now returns an `InvalidDigest` error.
* If the value is valid but does not match the payload, it returns a `BadDigest` error.
* Adds integration test cases for `PutBucketCors` with `Content-MD5`.
Fixes#1540Fixes#1538Fixes#1513Fixes#1425
Fixes SigV4 authentication and presigned URL error handling. Adds two sets of errors in the `s3err` package for these authentication mechanisms.
* Adds a check to return a custom "not supported" error when `X-Amz-Security-Token` is present in presigned URLs.
* Adds a check to return a custom "not supported" error when the `AWS4-ECDSA-P256-SHA256` algorithm is used in presigned URLs.
The debuglogger should be a top level module since we expect
all modules within the project to make use of this. If its
hidden in s3api, then contributors are less likely to make
use of this outside of s3api.
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
```
Fixes#961Fixes#1248
The gateway should return a `MissingContentLength` error if the `Content-Length` HTTP header is missing for upload operations (`PutObject`, `UploadPart`).
The second fix involves enforcing a maximum object size limit of `5 * 1024 * 1024 * 1024` bytes (5 GB) by validating the value of the `Content-Length` header. If the value exceeds this limit, the gateway should return an `EntityTooLarge` error.
We were trying to parse a non existing acl and returning an
internal server error due to invalid json acl data.
If the bucket acl does not exist, return a default acl with the
root account as the owner.
This fixes#1060, but does not address the invalid acl format
from s3cmd reported in #963.
niksis02
Ben McClelland
jonaustin09andBen McClelland