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.
Add IAMAssumeRoleWithWebIdentity_github_oidc_live, the only web-identity test that exercises AssumeRoleWithWebIdentity against a real external OIDC provider end-to-end: GitHub Actions' own issuer, with real discovery-document fetch, JWKS fetch, RS256 signature verification, claims mapping, and session credential issuance. Every other web-identity test in the suite uses a fake token that never reaches real signature verification. The test registers a throwaway OIDC provider and trust role scoped to this repo (via a distinct test audience and repo-scoped sub condition), fetches a real ID token from GitHub's runtime endpoint, assumes the role, and confirms the issued session credentials work with a follow-up GetCallerIdentity call. It cleans up the role and provider unconditionally and skips itself when run outside a GitHub Actions job with id-token: write permission (e.g. local runs or fork PRs, where GitHub downgrades OIDC permissions to read-only).
Add functional-iam-oidc.yml to run this test in CI on push to main and on same-repo pull_request runs, isolated from the full iam suite since it's the only test needing id-token: write.
Add a SKIP counter and skipF() alongside the existing runF/passF/failF, and report it in the final RAN/PASS/FAIL summary, so a test opting out via skipF() (as this one does when OIDC env vars aren't present) is visible instead of silently absent from the count.
Implements the `AssumeRoleWithWebIdentity` and `GetCallerIdentity` STS actions, letting callers exchange an external OIDC token for temporary credentials scoped to an IAM role. Token handling covers JWT claim parsing, issuer/audience resolution (including `azp` override semantics), JWKS fetching and caching with `singleflight`-deduplicated refresh, and rate-limited forced refresh on unrecognized `kid` values. OIDC provider thumbprint fetching now performs a real TLS handshake verified against the system trust store and the provider hostname (previously `InsecureSkipVerify`), since the observed certificate is persisted as a long-lived trust anchor rather than used once and discarded; all discovery-document and JWKS fetches go through an SSRF-safe HTTP client with bounded redirects and response size.
Adds policy `Condition` block evaluation, supporting `String`, `Numeric`, `Date`, `Bool`, `BinaryEquals`, and `IpAddress` operators along with their `IfExists`/`Not` variants and `ForAllValues`/`ForAnyValues` set qualifiers, plus policy variable substitution (e.g. `${aws:username}`) in supported operators. Adds identity-based inline policy evaluation and a new IAM authorization middleware that authorizes each request against action, resource, and condition context together, applying the session-policy-intersects-role-policy semantics for assumed-role sessions.
Adds a new debug logger `--log-level` flag (`silent`/`debug`/`unsafe`), along with a tree-based XML masker that redacts secrets and tokens at the property level in logged request/response bodies instead of skipping the whole body. The old `--debug/VGW_DEBUG` flag is kept as a deprecated alias for `--log-level=debug`, printing a console warning that points users at `--log-level` for finer-grained control.
Fixes a Vault storage bug where CAS (check-and-set) writes always read the current document version as 0 because `kvVersion` asserted metadata as `float64` while the Vault client actually returns `json.Number`, causing every write past the first to be rejected as a concurrent modification. Also adds a constant-time `SecureCompare` for signature/token comparisons in sigv4 auth.
Adds an integration test suite (`iam_access_control.go`) covering IAM access control across user, role, and session identities.
Add support for `CreateOpenIDConnectProvider`, `GetOpenIDConnectProvider`, `ListOpenIDConnectProviders`, `DeleteOpenIDConnectProvider`, `AddClientIDToOpenIDConnectProvider`, `RemoveClientIDFromOpenIDConnectProvider`, and `UpdateOpenIDConnectProviderThumbprint` on both the internal and Vault storage backends, rounding out the standalone IAM service with the same OIDC identity provider management AWS IAM exposes.
CreateOpenIDConnectProvider validates the issuer URL, enforces the client ID and per-provider client ID list limits, and accepts an optional ThumbprintList. When the caller omits ThumbprintList, the provider auto-fetches the thumbprint by opening an outbound TLS connection to the issuer URL and hashing its top-level CA certificate, matching real AWS behavior. This auto-fetch is configurable: it can be turned off with the `--disable-oidc-thumbprint-autofetch` CLI flag (or the `VGW_IAM_DISABLE_OIDC_THUMBPRINT_AUTOFETCH` environment variable) for restricted or air-gapped deployments where the IAM server shouldn't make outbound connections, in which case an omitted ThumbprintList is rejected instead. AddClientIDToOpenIDConnectProvider and RemoveClientIDFromOpenIDConnectProvider manage a provider's client ID list, and UpdateOpenIDConnectProviderThumbprint replaces its thumbprint list, all with the same length and format validation applied at creation time.
Provider ARNs are derived from the issuer URL, and GetOpenIDConnectProvider and DeleteOpenIDConnectProvider resolve providers by ARN, returning NoSuchEntity when a provider doesn't exist. ListOpenIDConnectProviders returns the full set of stored providers. These actions are wired into the IAM API router and given their own XML response types under iamapi/types, with a new iamapi/internal/iamutil package handling URL validation, thumbprint fetching and normalization, and ARN construction shared across the controller methods.
Add support for the `PutRolePolicy`, `GetRolePolicy`, `DeleteRolePolicy`, and `ListRolePolicies` actions in the IAM-compatible gateway service, extending role management with the same inline-policy lifecycle already available for IAM users. `PutRolePolicy` validates the policy name and document, parses the document for AWS-compatible syntax and semantic errors (missing actions/resources, malformed ARNs, disallowed principals, duplicate statement IDs, and so on), and rejects documents once the role's aggregate inline-policy size would exceed `MaxInlinePolicyBytesPerRole` (10240 bytes, distinct from the 2048-byte quota enforced for users). Putting a policy under an existing name overwrites its document in place. `GetRolePolicy` and `DeleteRolePolicy` look up or remove a named inline policy from a role, returning a `NoSuchEntity` error when the role or the policy is not found. `ListRolePolicies` returns a role's inline policy names in sorted order with marker-based pagination.
These actions are implemented for both the internal file-backed store and the Vault-backed store, wired into the IAM API router, and given their own XML response types under `iamapi/types`. A new `NoSuchEntityRolePolicy` error was added to `iamapi/iamerr` to mirror the existing user-policy error.
Adds `CreateRole`, `GetRole`, `ListRoles`, `DeleteRole`, and `UpdateAssumeRolePolicy` to the standalone IAM service, following the same controller/storage patterns established for users. Both the internal filesystem/S3-backed store and the Vault-backed store implement the new `Storer` methods, with role-specific indexing and lookup helpers mirroring the existing user ones.
Role creation requires a trust policy, passed as `AssumeRolePolicyDocument`. A trust policy is a distinct kind of IAM policy document that governs who (or what) is allowed to assume a role, rather than what actions the role itself is permitted to perform. Its grammar is effectively the inverse of an identity policy: `Principal` is required, `Action`/`NotAction` values must carry the `sts:` prefix, and `Resource`/`NotResource` are forbidden. This is implemented in `iamapi/policy/trust.go` as a new validation path alongside the existing identity-policy validation, and is reused by `UpdateAssumeRolePolicy` when replacing a role's trust policy.
Also fixes user name uniqueness enforcement to be case-insensitive, matching AWS IAM behavior, and applies the same case-insensitive handling to role names. The internal store now maintains lowercase name indexes for both users and roles, and the Vault store resolves the canonical stored key via a case-insensitive list-and-compare fallback since Vault's KV paths are case-sensitive.
Add support for AWS-compatible inline identity-based policies on IAM
users, implementing the `PutUserPolicy`, `GetUserPolicy`, `DeleteUserPolicy`, and `ListUserPolicies` actions on both the internal and Vault storage
backends.
- iamapi/policy is a new package that parses and validates policy documents against IAM's parameter-level constraints (max length, allowed charset) and policy grammar (Version, Effect, mutually exclusive Action/NotAction and Resource/NotResource, vendor-prefixed actions, ARN-shaped resources, no Principal/NotPrincipal, unique Sids).
- `PutUserPolicy` creates or replaces a named inline policy on a user, enforcing a 2048-byte aggregate quota across all of a user's inline policies (MaxInlinePolicyBytesPerUser), matching the AWS IAM quota.
- `GetUserPolicy` returns a policy's document RFC 3986 percent-encoded, matching how real IAM encodes the PolicyDocument response element.
- `DeleteUserPolicy` removes a named inline policy from a user.
- `ListUserPolicies` returns a paginated, sorted list of a user's inline policy names, honoring Marker/MaxItems like the other IAM list APIs.
- `DeleteUser` is now rejected with a DeleteConflict error if the user still has inline policies attached, mirroring the existing access-key delete-conflict behavior.
Add `CreateAccessKey`, `UpdateAccessKey`, `DeleteAccessKey`, `ListAccessKeys`, and `GetAccessKeyLastUsed` actions for managing user access keys and retrieving their latest usage details.
Generate AWS-style access key IDs and secrets, validate key identifiers and statuses, enforce per-user key quotas, and prevent deleting users that still own access keys. Persist access keys across internal and Vault storage backends with ownership indexing, pagination, and IAM-compatible errors and XML responses.
Closes#1640
Add a standalone AWS IAM Query API implementation for managing IAM users through standard AWS SDKs and the AWS CLI.
Server usage
Start the IAM server with internal file-backed storage:
mkdir -p /tmp/versitygw-iam
./versitygw --port 127.0.0.1:7070 --access user --secret pass iam --dir /tmp/versitygw-iam
Start the IAM server with Vault KV v2 storage using AppRole:
VGW_IAM_VAULT_ROLE_SECRET=<role-secret> ./versitygw --port 127.0.0.1:7070 --access user --secret pass iam --vault-endpoint-url http://127.0.0.1:8200 --vault-auth-method approle --vault-role-id <role-id> --vault-mount-path kv --vault-secret-storage-path iam
Vault authentication also supports root tokens, separate authentication and secret-storage namespaces, custom mount paths, server certificate validation, and mutual TLS client certificates.
Configure the AWS CLI credentials used by the IAM server:
export AWS_ACCESS_KEY_ID=user
export AWS_SECRET_ACCESS_KEY=pass
export AWS_DEFAULT_REGION=us-east-1
Implemented IAM actions
CreateUser creates an IAM user with an AWS-compatible ARN, generated AIDA user ID, creation timestamp, optional path, and tags. It validates usernames, paths, tag limits, reserved tag prefixes, duplicate tag keys, and existing users.
aws --endpoint-url http://127.0.0.1:7070 iam create-user --user-name bob
aws --endpoint-url http://127.0.0.1:7070 iam create-user --user-name bob --path /engineering/ --tags Key=team,Value=storage
GetUser returns a stored user or the root identity when requested without a username through the IAM Query API.
aws --endpoint-url http://127.0.0.1:7070 iam get-user --user-name bob
ListUsers returns users in deterministic username order and supports path filtering, marker-based pagination, and MaxItems limits.
aws --endpoint-url http://127.0.0.1:7070 iam list-users
aws --endpoint-url http://127.0.0.1:7070 iam list-users --path-prefix /engineering/ --max-items 100
UpdateUser updates the username and/or path, recalculates the user ARN, and rejects conflicts with existing users.
aws --endpoint-url http://127.0.0.1:7070 iam update-user --user-name bob --new-user-name robert --new-path /platform/
DeleteUser permanently removes an IAM user and returns AWS-compatible errors for missing users.
aws --endpoint-url http://127.0.0.1:7070 iam delete-user --user-name robert
IAM protocol and authentication
- Support the AWS IAM Query protocol version 2010-05-08 over GET and POST form requests.
- Return AWS-compatible XML responses, error documents, status codes, request IDs, user metadata, and pagination fields.
- Authenticate root credentials with AWS Signature Version 4 for the IAM service in us-east-1.
- Support both Authorization-header and query-string SigV4 authentication.
- Validate credential scope, signed headers, timestamps, clock skew, content length, signatures, and unsupported signature or session-token modes.
- Add IAM-specific validation and error mapping for malformed requests, invalid actions, duplicate entities, missing users, throttling, and internal failures.
Storage implementations
- Add an internal JSON-backed store using iam.json and iam.json.backup with atomic temporary-file replacement, concurrent access protection, stable ordering, pagination, and persistence across restarts.
- Add a Vault KV v2 store with one secret per user, CAS-based duplicate protection, permanent deletion, AppRole reauthentication, namespace support, configurable authentication and KV mounts, root-token authentication, and TLS/mTLS configuration.
- Introduce a common Storer interface and require exactly one storage backend to be configured.
Server and embedding support
- Register the new `versitygw iam` command with environment-variable and CLI configuration for both storage backends.
- Add `embedgw.RunIAMAPI` and `IAMConfig` for embedding the IAM service in Go applications.
Gateway-level internal packages
- Add `internal/iamstore` as a reusable generic file-backed IAM persistence engine and migrate the existing gateway internal IAM service to it.
- Add `internal/sigv4auth` for shared SigV4 header and presigned-query parsing, canonical request generation, signature verification, and structured authentication errors.
- Refactor the S3 authentication paths to use the shared SigV4 implementation while preserving S3-specific error responses.
- Add `internal/httpctx` for shared Fiber context keys and AWS-style request ID handling.
- Add `internal/routekit` for shared query, form, and header route matchers.
- Add `internal/netutil` for reusable certificate storage, hostname-aware listeners, multi-address serving, TLS listeners, and UNIX socket handling.
- Update the custom SigV4 signer to honor an explicitly supplied signed-header list so unrelated headers do not alter IAM signatures.
Testing and CI
- Add AWS IAM SDK-based integration coverage for all supported user actions, header authentication, query authentication, validation, errors, filtering, and pagination.
- Split standalone IAM tests into `versitygw test iam` and retain existing gateway IAM tests under `versitygw test gw-iam`.
- Add unit coverage for controllers, authentication, routing, storage, embedding, listeners, request matching, persistence, and signing behavior.
- Add `runiamtests.sh` to exercise internal storage over HTTP and HTTPS plus Vault storage through AppRole.
- Add a dedicated IAM functional-test workflow with a Vault service and merged runtime coverage reporting.
- Include the IAM test runner in shellcheck and add the AWS IAM SDK dependency.
Introduce an opt-in mode that derives ETags from checksums instead of relying on
MD5 assumptions, aligning with AWS-compatible scenarios where ETag should be
treated as an opaque identifier rather than a content-MD5 signal.
This can significantly reduce CPU load on the server to disable MD5 checksums
when we are already validating data with other checksums.
This change adds --data-integrity-etag and VGW_DATA_INTEGRITY_ETAG support for
both posix and scoutfs backends. In this mode, PUT object ETags, multipart part
ETags, and completed multipart object ETags are checksum-derived.
Keep null as the stored object version ID when bucket versioning is suspended, but omit x-amz-version-id from the PutObject response to match Amazon S3.
Update the existing versioning integration coverage to distinguish the PutObject response from the null version returned by ListObjectVersions, and verify empty response headers are not rendered.
Fixes#2164
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The copy-source header was being interpreted differently by request
validation and the backend parser. An encoded ?versionId= separator
could be decoded at one layer but treated as part of the object path
at another, which opened a path traversal risk on filesystem-backed
copy operations.
Align backend copy-source parsing with validation by decoding the
header before splitting the versionId suffix, so both layers derive
the same bucket, object, and versionId values. This closes the
traversal path and adds regression coverage for encoded
copy-source inputs.
Reported by 5ud0 / Tarmo Technologies.
quote part etags across all azure multipart surfaces (uploadpart,
listparts, uploadpartcopy) via a shared quoteETag helper, matching the
s3 contract and the posix backend's GenerateEtag convention. populate
the previously-empty UploadPartCopy CopyPartResult with the quoted etag
and last-modified. normalize the client-supplied etag in
CompleteMultipartUpload with backend.TrimEtag so both quoted and raw
etags are accepted. add an azure-full-flow integration test asserting
part etags are quoted and consistent across uploadpart, listparts and
completemultipartupload.
This change adds Windows functional test execution in CI and updates
backend handling so windows filesystem error/path semantics map correctly
to expected S3 outcomes.
The only meta supported on windows right now is sidecar, so the tests
in windows mode also skip sidecar skips.
Future work is to address the skips and/or more clearly document
the unsupported/incompatible behavior on windows.
The windows support will still remain best effort, but these tests
should at least flag when future changes introduce incompatible
behavior on windows.
Fixes#2187
Enforce maximum default retention periods when parsing PutObjectLockConfiguration requests. Reject Days values greater than 36500 and Years values greater than 100 with InvalidArgument errors.
Fixes#2185
Add asterisk handling for `If-Match` and `If-None-Match` read preconditions across `GetObject`, `HeadObject`, `CopyObject`, and `UploadPartCopy`.
`If-Match`: `*` now matches any `ETag`, while `If-None-Match`: `*` returns `304 Not Modified`.
Fixes#2179
Treat a present but empty `Content-MD5` header as an invalid digest instead of handling it as if the header were absent. This makes PUT operations return `InvalidDigest` for empty `Content-MD5` values while preserving existing behavior for missing headers.
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.
Integrate x-amz-website-redirect-location across object metadata flows so uploads, copies, multipart creation, HEAD, and GET preserve and return redirect locations, and website hosting applies object-level redirects from the stored value.
Enhances the static website hosting implementation with more complete S3-compatible behavior across request handling, backend storage, validation, CORS, and errors.
Adds dedicated website endpoint handling for GET, HEAD, and OPTIONS requests, including index document resolution, error document serving, redirect-all support, pre-fetch and post-error routing rules, query string preservation in redirects, public access checks before object reads, and method-not-allowed responses.
Improves error handling for website responses by returning S3-compatible HTML error bodies with request IDs, host IDs, x-amz-error-code, x-amz-error-message, and specialized error fields. This also fixes website-related validation errors to return more accurate S3-style error codes and messages, including invalid redirect protocols, invalid HTTP redirect/error codes, conflicting routing rule replacements, routing rule limits, and oversized website configuration requests.
Adds website CORS support for GET, HEAD, and OPTIONS preflight requests, including bucket CORS lookup through website host bucket resolution, allowed origin/method/header validation, exposed header handling, ETag exposure, Vary headers, max-age handling, and CORS access-denied responses.
Adds debug logging around website configuration parsing, validation failures, CORS checks, backend lookup failures, and internal website error paths to make failures easier to diagnose.
Adds compressed website configuration storage so larger configs fit backend metadata limits, including gzip storage for POSIX extended attributes and base64-encoded compressed metadata for Azure. Also adds Azure PutBucketWebsite, GetBucketWebsite, and DeleteBucketWebsite support.
Adds and expands test coverage for website config validation, S3-compatible HTML error bodies, website routing behavior, public access enforcement, HEAD behavior, CORS handling, PutBucketWebsite limits, and end-to-end website hosting through a Docker-based dnsmasq test setup and CI workflow.
Replace PutBucketWebsite, GetBucketWebsite, DeleteBucketWebsite
NotImplemented test stubs with comprehensive integration tests covering:
- non-existing bucket errors
- validation (empty suffix, suffix with slash, invalid protocol, mutual
exclusion of RedirectAllRequestsTo and IndexDocument)
- successful put/get round-trips for both index+error and redirect-all configs
- delete idempotency and verification
Signed-off-by: Marc Singer <marc@singer.gg>
Add error document serving, routing rules, and integration tests
Implement Features 1 and 2 of S3 static website hosting:
- WebsiteErrorDocument controller wrapper intercepts 4xx errors on
website-enabled buckets and serves the configured error document or
evaluates post-request routing rules (error code match redirects)
- ResolveWebsiteIndex middleware now caches parsed WebsiteConfiguration
in context, handles RedirectAllRequestsTo, evaluates pre-request
routing rules (key prefix match redirects), and rewrites directory
keys for index document
- MatchPreRequestRule and MatchPostRequestRule methods on
WebsiteConfiguration for routing rule evaluation
- 14 unit tests for routing rule matching
- 7 integration tests covering error document, routing rules,
redirect-all, and index document behavior
Signed-off-by: Marc Singer <marc@singer.gg>
Add separate website hosting endpoint with virtual-host routing
Signed-off-by: Marc Singer <marc@singer.gg>
Support catch-all mode for website endpoint when --website-domain is omitted
Signed-off-by: Marc Singer <marc@singer.gg>
Validate required signed headers for both Authorization-header SigV4 requests and presigned URLs. The required signed header set is now `host` plus every incoming header with the `x-amz-` prefix.
During request reconstruction, signed headers and explicitly ignored headers are copied into the generated request used for signature verification. If an incoming `x-amz-*` header is present but missing from the client-provided `SignedHeaders`, return `AccessDenied` with a `HeadersNotSigned` field. The `host` header remains part of the canonical request and signed header calculation.
Previously, a client could sign a request without an S3 control header and then add that header after signing. For example, a presigned `PUT` URL could be generated with only `host` signed, then the actual request could include an unsigned `X-Amz-Tagging` or `X-Amz-Copy-Source` header. Because the verifier reconstructed the request only from `SignedHeaders`, that extra header was omitted from signature calculation and could pass authentication even though it changed the request semantics. This is now rejected with `AccessDenied`.
Expose v4 helper methods for checking required and ignored headers, and update canonical header signing so ignored headers can still be included when a client explicitly lists them in `SignedHeaders`, while `Authorization` remains excluded from signature calculation.
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.
Fix the gateway panic when validating malformed bucket ownership controls bodies with no rules. The handler now checks the rules count before indexing the first rule.
Validate multipart PostObject key fields with the existing object name rules so path traversal and degenerate names return BadRequest. This prevents crafted object keys from escaping the gateway root.
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.
Directories that exist on the filesystem but were not explicitly created
via S3 (put-object with a key ending in '/') do not have an etag
value. ListObjectsV2 already uses the presence of this attribute to
decide whether to include a directory as an object. GetObject and
HeadObject were not performing this check, so they would successfully
return directories that ListObjectsV2 would not list.
Add the etag attribute check in GetObject and HeadObject: if a
directory path is requested but has no etag xattr, return 404. This
makes all three operations agree on which directories are S3 objects.
Fixes#2130
niksis02
Luke McCrone
Ben McClellandandGitHub
Ed Espino
Marc Singerandniksis02