Commit Graph
4 Commits
Author SHA1 Message Date
Chris Lu 7522e17b6d iceberg: vend table-scoped credentials to clients that ask for delegation (#10777)
* iceberg: vend table-scoped credentials to clients that ask for delegation

The catalog recognised X-Iceberg-Access-Delegation: vended-credentials
and then deliberately said nothing, because it had nothing to vend: it
withheld even the S3 endpoint so the client would keep the credentials it
was configured with. That left every engine expecting the catalog to hand
out access - Snowflake, Databricks, Trino with vending, any multi-tenant
setup - needing static S3 keys distributed out of band.

Mint an STS session per request instead, scoped by a session policy to
the table's own prefix plus the bucket listing needed to resolve it, and
return it in the load response config and storage-credentials. The role
to assume is named by -s3.iceberg.credentialRole; its trust policy is
what decides whether a caller may assume it, and vending stays off until
it is set. A failed mint falls back to the old silence rather than
handing back an endpoint the client cannot sign for.

* iceberg: keep vended credentials inside the table prefix

Review follow-ups on credential vending:

Listing was granted on the bucket ARN with no condition, so a credential
vended for one table could enumerate every other table's object names.
Constrain s3:prefix to the table's own prefix, which the S3 gateway
already populates for list requests.

A table location carrying * or ? would have gone into the policy's
resource pattern unescaped and widened the session to sibling prefixes.
Refuse to vend for such a location rather than escaping it; nothing the
catalog generates contains those characters.

DurationSeconds skipped the 900..43200 bounds the other assume-role paths
enforce, so -s3.iceberg.credentialDurationSeconds could ask for a session
outside them. The check is now shared by all three entry points.

* iceberg: return the vended credentials from buildFileIOConfig itself

buildStorageConfig was a second name for what buildFileIOConfig already
did; it now returns the storage credentials alongside the properties, and
callers that only want the properties drop them.

* iceberg: split the vended bucket grants, and refuse a whole-bucket scope

The prefix condition sat on a statement that also granted
GetBucketLocation and ListBucketMultipartUploads, neither of which carries
an s3:prefix to satisfy it, so both were denied for every vended
credential. GetBucketLocation moves to its own unconditioned statement.
ListBucketMultipartUploads is dropped: Iceberg writers complete and abort
by upload id, and granting it either leaks in-flight keys bucket-wide or
breaks on the same missing prefix.

A table whose location has no prefix - one registered at the bucket root -
would have been vended read and write over every other table in the
bucket. Refuse, the way a location with wildcards is refused.
2026-08-16 12:57:12 -07:00
Chris Lu d044839ab2 iceberg: make a table commit a compare-and-swap (#10775)
* iceberg: make a table commit a compare-and-swap

The catalog validated the caller's version token, ran its authorization
checks, and only then wrote the new metadata xattr. Two engines
committing against the same base both passed that check and both wrote,
so the second silently dropped the first one's snapshot. Both also derive
the same v{N}.metadata.json name and the file write overwrote, leaving
the surviving pointer aimed at the loser's metadata - and the loser's
conflict cleanup then deleted the winner's file.

Write the metadata file with an exclusive create and update the xattr
conditionally on the bytes the handler read, the way the maintenance
worker already commits. A writer that lost the race re-reads and retries,
and reports 409 CommitFailedException once out of attempts.

* iceberg: stage a commit under a unique name when the versioned one is taken

Two follow-ups from review of the commit compare-and-swap:

Refusing to overwrite v{N}.metadata.json also refused to get past a file
left behind by a commit that died between staging and updating the
pointer. Every later commit derived the same name, saw the collision, and
reported a conflict, so the table stayed uncommittable until an orphan
sweep removed the file. Stage under v{N}-{uuid} instead: neither writer's
file is overwritten and the catalog pointer still decides who won, which
is how the maintenance worker has always staged its own metadata.
metadataVersionFromLocation learned to read the version back out of that
name.

The conditional update guarded only the metadata attribute while the
write replaced the whole entry, so a policy or tag written in the same
window was silently reverted. Guard every catalog attribute, which turns
that into a conflict the caller retries on fresh state.

* iceberg: give saveMetadataFile the exclusive flag instead of a second name

saveNewMetadataFile, saveMetadataBlobExclusive and uniqueMetadataFileName
were three new names around one existing helper. The flag now rides on
saveMetadataFile and saveMetadataBlob, and the unique-name construction
sits where it is used.

* iceberg: reuse the filer CAS helpers #10773 added, and stage transactions exclusively

#10773 landed mutateEntryExtended, which already writes an entry back under a
whole-entry precondition and retries. Drop the helper this branch added and
route the table commit through it: the check that the metadata is still the
one this request read now lives in the mutation, where it sees current state.

The policy the request was authorized against is asserted too, so an
administrator restricting it mid-commit sends the caller back through
authorization instead of having a stale decision applied. Bucket and
namespace policies live on other entries and a single-entry precondition
cannot cover them.

Multi-table transactions stage their metadata exclusively for the same
reason single-table commits do, and carry the name they landed on into the
pointer flip.
2026-08-16 12:55:42 -07:00
Chris Lu d448e9db7b iceberg: withhold the S3 endpoint from credential-vending clients (#10570)
* iceberg: withhold the S3 endpoint from credential-vending clients

A client that sends X-Iceberg-Access-Delegation: vended-credentials builds
its storage credential out of the LoadTable config and drops the one it was
configured with. We vend no credentials, so the endpoint we advertised left
DuckDB signing nothing: every metadata and data file came back 403, and its
attempt to refresh the empty credential 404ed on stage-created tables.

Answer those clients with no config at all so they keep their own
credentials. Clients that do not ask for delegation still get the endpoint.

* iceberg: mark load responses as varying on the delegation header

The FileIO config in a table or view load response now depends on whether
the client asked for vended credentials, so a cache between us and the
client must key on that header rather than on the URL alone.

* test: cover the DuckDB vended-credentials access pattern

Runs weed mini with -s3.externalUrl, which is what makes the catalog
advertise an endpoint at all, and checks both halves: a plain LoadTable
still gets the endpoint, while one asking for vended credentials never gets
an endpoint without the credentials to sign with. The DuckDB round trip
creates a table from a query and reads it back, which is the flow that
failed with 403 on every data file.
2026-08-04 18:14:34 -07:00
Chris Lu 0403e47ef6 iceberg: support views (#10069)
* s3tables: tag table entries and exclude views from table listings

* s3tables: add view CRUD operations

* iceberg: support view create, load, exists, drop, and list

* iceberg: support view update

* iceberg: test view error classification and metadata round-trip

* iceberg: pre-check existence and write view metadata only after create

* iceberg: map view namespace-not-found to 404

* iceberg: test view create namespace-404 and duplicate no-clobber

* s3tables: tag view metadata and entry type atomically

CreateView wrote ExtendedKeyMetadata and ExtendedKeyEntryType in two
UpdateEntry calls, so a partial failure could leave a view directory
untagged. Add setExtendedAttributes to set both in one UpdateEntry.

* iceberg: roll back view registration when metadata write fails

The metadata file is written after the catalog registers the view. If
that write fails, drop the just-created view so it doesn't linger
pointing at a missing metadata.json. Reuse the DeleteView path via a
shared dropView helper.
2026-06-23 15:22:31 -07:00