Combine length, character, and reserved pattern validation into validateBucketName()
which returns descriptive error messages. Keep isValidBucketName() for backward
compatibility. This simplifies handler validation and provides better error reporting.
Define a separate tableNamePatternStr constant for the table name component in
the ARN regex, even though it currently has the same value as
tableNamespacePatternStr. This improves code clarity and maintainability, making
it easier to modify if the naming rules for tables and namespaces diverge in the
future.
Make ListTables authorization consistent with GetTable/CreateTable:
1. ListTables authorization now evaluates policies instead of owner-only checks:
- For namespace listing: checks namespace policy AND bucket policy
- For bucket-wide listing: checks bucket policy
- Uses CanListTables permission framework
2. Remove owner-only filter in listTablesWithClient that prevented policy-based
sharing of tables. Authorization is now enforced at the handler level, so all
tables in the namespace/bucket are returned to authorized callers (who have
access either via ownership or policy).
3. Add flexible PolicyDocument.UnmarshalJSON to support both single-object and
array forms of Statement field:
- Handles: {"Statement": {...}}
- Handles: {"Statement": [{...}, {...}]}
- Improves AWS IAM compatibility
This ensures cross-account table listing works when delegated via bucket/namespace
policies, consistent with the authorization model for other operations.
Address three related ownership consistency issues:
1. CreateNamespace now sets OwnerAccountID to bucketMetadata.OwnerAccountID
instead of request principal. This prevents namespaces created by
delegated callers (via bucket policy) from becoming unmanageable, since
ListNamespaces filters by bucket owner.
2. CreateTable now:
- Fetches bucket metadata to use correct owner for bucket policy evaluation
- Uses namespaceMetadata.OwnerAccountID for namespace policy checks
- Uses bucketMetadata.OwnerAccountID for bucket policy checks
- Sets table OwnerAccountID to namespaceMetadata.OwnerAccountID (inherited)
3. GetTable now:
- Fetches bucket metadata to use correct owner for bucket policy evaluation
- Uses metadata.OwnerAccountID for table policy checks
- Uses bucketMetadata.OwnerAccountID for bucket policy checks
This ensures:
- Bucket owner retains implicit "owner always allowed" behavior even when
evaluating bucket policies
- Ownership hierarchy is consistent (namespace owned by bucket, table owned by namespace)
- Cross-principal delegation via policies doesn't break ownership chains
Move bucket name extraction outside the if/else block in
extractResourceOwnerAndBucket since the logic is identical for both
ResourceTypeTable and ResourceTypeBucket cases. This reduces code
duplication and improves maintainability.
The extraction pattern (parts[1] from /tables/{bucket}/...) works for
both resource types, so it's now performed once before the type-specific
metadata unmarshaling.
Implement resource-specific policy validation to prevent over-broad
permission grants. Add matchesResource and matchesResourcePattern functions
to validate statement Resource fields against specific resource ARNs.
Add new CheckPermissionWithResource function that includes resource ARN
validation, while keeping CheckPermission unchanged for backward compatibility.
This enables policies to grant access to specific resources only:
- statements with Resource: "arn:aws:s3tables:...:bucket/specific-bucket/*"
will only match when accessing that specific bucket
- statements without Resource field match all resources (implicit *)
- resource patterns support wildcards (* for any sequence, ? for single char)
For future use: Handlers can call CheckPermissionWithResource with the
target resource ARN to enforce resource-level access control.
Replace silent error swallowing (err == nil) with proper error distinction
for bucket policy reads. Now properly checks ErrAttributeNotFound and
propagates other errors as internal server errors.
Fixed 5 locations:
- handleCreateNamespace (policy fetch)
- handleDeleteNamespace (policy fetch)
- handleListNamespaces (policy fetch)
- handleGetNamespace (policy fetch)
- handleGetTableBucket (policy fetch)
This prevents masking of filer issues when policies cannot be read due
to I/O errors or other transient failures.
Change ARN generation to use resource OwnerAccountID instead of caller
identity (h.getAccountID(r)). This ensures ARNs are stable and consistent
regardless of which principal accesses the resource.
Updated generateTableBucketARN and generateTableARN function signatures
to accept ownerAccountID parameter. All call sites updated to pass the
resource owner's account ID from metadata.
This prevents ARN inconsistency issues when multiple principals have
access to the same resource via policies.
Replace strict ownership check in CreateTable with policy-based authorization.
Now checks both namespace and bucket policies for CreateTable permission,
allowing delegation via resource policies while still respecting owner bypass.
Authorization logic:
- Namespace policy grants CreateTable → allowed
- Bucket policy grants CreateTable → allowed
- Otherwise → denied (even if same owner)
This enables cross-principal table creation via policies while maintaining
security through explicit allow/deny semantics.
Add automatic normalization of operations to full IAM-style action names
(e.g., 's3tables:CreateTableBucket') in CheckPermission(). This ensures
policy statements using prefixed actions (s3tables:*) correctly match
operations evaluated by permission helpers.
Also fixes incorrect r.Context() passed to GetIdentityNameFromContext
which expects *http.Request. Now passes r directly.
Move validateNamespace call outside of filerClient.WithFilerClient closure
so that validation errors return HTTP 400 (InvalidRequest) instead of 500
(InternalError).
Before: Validation error inside closure → treated as internal error → 500
After: Validation error before closure → handled as bad request → 400
This provides correct error semantics: namespace validation is an input
validation issue, not a server error.
Replace error-swallowing pattern where all errors from getExtendedAttribute
were ignored for bucket policy reads. Now properly distinguish between:
- ErrAttributeNotFound: Policy not found is expected; continue with empty policy
- Other errors: Return internal server error and stop processing
Applied fix to all bucket policy reads in:
- handleDeleteTableBucketPolicy (line 220)
- handleTagResource (line 313)
- handleUntagResource (line 405)
- handleListTagsForResource (line 488)
- And additional occurrences in closures
This prevents silent failures and ensures policy-related errors are surfaced
to callers rather than being silently ignored.
Replace the custom suffix-only wildcard implementation in matchesActionPattern
and matchesPrincipal with the policy_engine.MatchesWildcard function from
PR #8052. This enables full wildcard support including:
- Middle wildcards: s3tables:Get*Table matches GetTable
- Question mark wildcards: Get? matches any single character
- Combined patterns: s3tables:*Table* matches any action containing 'Table'
Benefits:
- Code reuse: eliminates duplicate wildcard logic
- Complete IAM compatibility: supports all AWS wildcard patterns
- Performance: uses efficient O(n) backtracking algorithm
- Consistency: same wildcard behavior across S3 API and S3 Tables
Add comprehensive unit tests covering exact matches, suffix wildcards,
middle wildcards, question marks, and combined patterns for both action
and principal matching.
Create extractResourceOwnerAndBucket() helper to consolidate the repeated pattern
of unmarshaling metadata and extracting bucket name from resource path. This
pattern was duplicated in handleTagResource, handleListTagsForResource, and
handleUntagResource. Update all three handlers to use the helper.
Also update remaining uses of getPrincipalFromRequest() (in handler_bucket_create,
handler_bucket_get_list_delete, handler_namespace) to use getAccountID() after
consolidating the two identical methods.
Update handleListTagsForResource to fetch and pass bucket policy to
CheckPermission, matching the behavior of handleTagResource/handleUntagResource.
This enables bucket-policy-based permission grants to be evaluated for
ListTagsForResource, not just ownership-based checks.
Both methods had identical implementations - they return the account ID from
request header or fall back to handler's default. Remove the duplicate
getPrincipalFromRequest and use getAccountID throughout, with updated comment
explaining its dual role as both caller identity and principal for permission
checks.
- Add CanTagResource() to check TagResource permission
- Add CanUntagResource() to check UntagResource permission
- Update CanManageTags() to check both operations (OR logic)
This prevents UntagResource from incorrectly checking 'ManageTags' permission
and ensures each operation validates the correct permission when per-operation
permissions are enforced.
Replace misleading character-only error message with generic 'invalid bucket
name'. The isValidBucketName() function checks multiple constraints beyond
character set (length, reserved prefixes/suffixes, start/end rules), so a
specific character message is inaccurate.
The field name 'Schema' was confusing given it holds a *TableMetadata struct
and serializes as 'metadata' in JSON. Rename to 'Metadata' for clarity and
consistency with the JSON tag and intended meaning.
- Remove dead URL unescape for namespace (regex [a-z0-9_]+ cannot contain
percent-escapes)
- Add URL decoding and validation of extracted table name via
validateTableName() to prevent callers from bypassing request validation
done in other paths
Enforce the same bucket name validation rules (length, characters, reserved
prefixes/suffixes) when extracting from ARN. This prevents accepting ARNs
that the system would never create and ensures consistency with
CreateTableBucket validation.
MaxBuckets is user-controlled and used in uint32(maxBuckets*2) for ListEntries.
Very large values can overflow uint32 or trigger overly expensive scans. Cap
MaxBuckets to 1000 and reject out-of-range values, consistent with MaxTables
handling and S3 MaxKeys validation elsewhere in the codebase.
MaxTables is user-controlled and influences gRPC ListEntries limits via
uint32(maxTables*2). Without an upper bound, very large values can overflow
uint32 or cause excessively large directory scans. Cap MaxTables to 1000 and
return InvalidRequest for out-of-range values, consistent with S3 MaxKeys
handling.
Add request body size limiting (10MB) to readRequestBody method:
- Define maxRequestBodySize constant to prevent unbounded reads
- Use io.LimitReader to enforce size limit
- Add explicit error handling for oversized requests
- Prevents potential DoS attacks via large request bodies
Remove premature HTTP error writes from within WithFilerClient closure
to prevent duplicate status code responses. Error handling is now
consistently performed at the top level using isAuthError.
Chris Lu
Chris Lu