tls: drop the handshake records that are sealed after our own FIN - #43957
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Status How to reproduce, on main (with #43947 merged), one test for each run:
With this PR all of them pass. The released 1.4.2 shows the same stall in a two-client probe. #43947 is merged, and this branch is rebased on main. |
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Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.
Beyond the inline findings, I also checked whether the new drop branches in openssl.c can swallow application data: us_internal_ssl_write refuses entry once us_internal_ssl_is_shut_down sees POLL_TYPE_SOCKET_SHUT_DOWN (openssl.c:2714), and nothing inside its SSL_write loop can send a FIN, so only handshake records and alerts reach ssl_can_still_write paths. The "0 means spill pending" return of ssl_flush_write_batch is also unchanged for every caller that inspects it (only the 131072-byte mid-write flush does, and it is unreachable after a FIN).
Extended reasoning...
The change adds a small helper to the usockets TLS layer that drops sealed records after the socket has sent its FIN or closed, in both the unbatched BIO write path and the batched flush path, plus six new tests. It touches the TLS write path (security-sensitive transport code) in a stacked PR, and the verified findings are test-quality nits only; a human should still weigh the drop semantics against the base PRs.
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Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.
Both nits from the previous round (relay helper now tracks and destroys its sockets; the raw socket's error is wired to reject) are addressed in the new commits. Beyond the inline finding, I also checked that the shared us_internal_socket_can_raw_write predicate is behavior-preserving at all three socket.c sites (us_socket_is_closed is exactly flags.is_closed, same polarity), and that the flush-path drop returning 0 without setting ssl_fatal_error cannot stall us_internal_ssl_write's 128KB flush loop, since that entry point already refuses writes once the poll type is POLL_TYPE_SOCKET_SHUT_DOWN.
Extended reasoning...
The native change is small (two early-outs in openssl.c gated on a new shared predicate in internal.h, plus a refactor of three gates in socket.c) but sits on the usockets TLS write path and the loop-wide spill slot, and the PR is stacked on two unmerged PRs, so a human look at the design remains worthwhile. It touches no auth or input-parsing surface; the only behavioral effect is dropping ciphertext that a FIN already made unsendable. The remaining inline finding is a test-structure nit.
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Navigate logical layers of code changes, visualize relationships, and explore their blast radius. 🧰 Additional context used📚 Code guidelines (1)WalkthroughTLS handshake handling now distinguishes half-close events from writable events. Raw TLS writes that cannot be delivered after FIN are consumed without retry or spill. Verification results remain available after shutdown when peer-chain verification occurred. Tests cover shutdown handshakes, verification outcomes, and backpressure. ChangesTLS shutdown during handshake
Suggested reviewers: Priority: ⬆️ High Merge Risk: 🔵 Low · up to The TLS shutdown fix appears mergeable, but the regression test should report an early client close directly rather than waiting for a timeout. 🚥 Pre-merge checks | ✅ 4✅ Passed checks (4 passed)
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us_socket_raw_write sends nothing once the FIN went out. A record that the handshake seals after that can never leave. - ssl_flush_write_batch drops it. A spill for it held the one spill slot of the loop until the socket closed, and us_internal_ssl_close waited for it. - BIO_s_custom_write drops it on the unbatched path. A write retry stalled the handshake while another socket held the spill slot.
…drops - us_internal_socket_can_raw_write (internal.h) replaces the three copies of the condition in socket.c and the private one in openssl.c. - New tests: records that a socket seals before its handshake completes, the flush for another socket, a rejecting TLS 1.2 server while a slow reader holds the spill slot, and the one-segment flight of the sockets that follow a half-closed handshake. - A test that times out runs no finally. afterAll releases what it left.
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Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.
Beyond the inline finding, I also checked the two new native drop branches: the early return 0 in ssl_flush_write_batch leaves no stale batch state (len/owner are already cleared at packages/bun-usockets/src/crypto/openssl.c:615-616 before the raw write), and the unguarded ssl_drain_spill is consistent because us_internal_ssl_shutdown defers the FIN behind any spill (openssl.c:2821-2825), so a socket that sent its FIN cannot own the slot. Application data cannot reach either branch: us_internal_ssl_write refuses writes once the socket is shut down (openssl.c:2710).
Extended reasoning...
The native change is three small, equivalent predicate replacements in socket.c plus two guarded drop branches in openssl.c on the TLS write path; the rest is test coverage. A human should still weigh the TLS record-drop semantics, and the one inline finding is about test hygiene rather than the fix itself.
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I reviewed the latest five commits and found no bugs; the earlier inline nits (raw-socket error wiring, relay helper tracking its connections, describe.serial, leftOpen registration for the slow-reader writer) are all addressed in code. Because this changes what the uSockets TLS write path does with sealed records, a human look at the two drop sites in packages/bun-usockets/src/crypto/openssl.c is still worthwhile.
What was reviewed:
us_internal_socket_can_raw_writeis exactly the oldis_closed || poll type == SHUT_DOWNcondition (us_socket_is_closedis justs->flags.is_closed), so the three socket.c replacements are behavior-preserving and still avoidus_socket_is_shut_down().- Both drops in openssl.c are only reachable after
us_socket_raw_writereturned 0 because the FIN went out or the fd is closed;ssl_write_batch_len/owner are already cleared before the earlyreturn 0, and no spill slot is claimed, so nothing dangles. - The only caller that acts on a 0 from
ssl_flush_write_batchis the application-data loop inus_internal_ssl_write, which cannot run after a FIN (us_internal_ssl_is_shut_downchecks the poll type first). ssl_drain_spillis intentionally unguarded:us_internal_ssl_shutdowndefers the FIN behind a spill, so a socket with a FIN out has no spill to drain.
Extended reasoning...
The change is three small native edits (a shared inline predicate in internal.h, three call-site replacements in socket.c, and two early-return drop sites in openssl.c) plus about 700 lines of new tests in test/js/bun/net/socket.test.ts and test/js/node/tls/. It touches the TLS transport write path, which is a security-relevant surface: records sealed after the socket's own FIN are now silently dropped instead of parked in the loop's spill slot. The native refactor was verified equivalent to the previous conditions and the drop paths leave batch and spill state consistent, and the author addressed every inline nit from prior runs, which is why no findings are reported. It is not approved outright because deliberately dropping TLS records in the shared uSockets layer is a design decision on a critical path that warrants a maintainer's judgment, and no CODEOWNERS entry covers packages/bun-usockets.
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Updated 4:44 PM PT - Oct 2nd, 2026
@dylan-conway, your commit eb1061a is building: |
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Merge order against #44290: #44290 has to merge first. Measured today on debug builds of The probe makes five connections, one after the other, in one process. Each is
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…r end() (#44290) Regression from #42181 (in no release). Merge before 1.4.3 is tagged, and before #43957 and #43962. ### Problem - After `end()` during its handshake, a node:tls client accepts a trusted certificate for another name: no error, and it reads the server's data. Node and Bun 1.4.2 report `ERR_TLS_CERT_ALTNAME_INVALID`. - `on_handshake` (`src/runtime/socket/socket_body.rs`) passed its name verdict to the handler as the success flag. After `end()`, `onClientHandshake` (`src/js/node/net.ts:496`) reads a failure with no error as the client's own close and skips `checkServerIdentity`. ### Fix - `on_handshake` no longer runs the native name check for a node:tls socket. The handler's flag is the handshake result. - `Bun.connect` and `upgradeTLS` sockets do not change. - Verified: `node-tls-duplex-end-verify.test.ts`, 19 new tests. `main` fails 18. Node v26.3.0 passes 49, skips 1. - Self-reviewed: 10 concerns raised, 10 addressed. One is #44422 (`onClientHandshake` reads some failed handshakes as established). ### Background - node:tls checks the name in JS (`checkServerIdentity`), on sockets that `DEFERS_SERVER_IDENTITY` marks. The native check ran for them: another name gave `(false, null)`, like a handshake that fails after this side's FIN. - Considered a `getAuthorizationError()` test in the guard, or a second flag variable: both keep an unused native check. ### Downsides - Needs a maintainer's yes: the internal `socket._handle.authorized` and `getAuthorizationError()` of a node:tls client drop the name check (no reader in `src/js` or `test`). The public values do not change. - Still open (#43957): only the first such connection of a process reports if its server keeps its side open. <details><summary>Notes</summary> **The regression** (`tls.connect({ socket })` on a connected socket, then `end()`. Trusted chain, certificate for another name, server in the same process, 3 runs each) | Runtime | Output | |---|---| | Node v26.3.0 | `finish, error ERR_TLS_CERT_ALTNAME_INVALID, close` | | Bun 1.4.2 (744846f) | `error ERR_TLS_CERT_ALTNAME_INVALID, close` | | Bun 1.3.13 | `end, finish, error ECONNRESET, close` | | canary 1.4.3-canary.1 (367d939, has #42181) | `finish, end, close`, no error | | this PR | `finish, error ERR_TLS_CERT_ALTNAME_INVALID, close` | - #42181 (44e51b7) is on `main` and is not an ancestor of the tag `bun-v1.4.2`. The client handler at that tag has no such guard. **Merge order, and why** - This PR first. Both later PRs let more handshakes complete after `end()`, and on `main` each of those accepts a certificate for another name. - #43957 removes the engine defect that today keeps the second and later connections of a process from completing such a handshake. Merged before this PR, it turns one silently accepted connection into all of them. Measured with five connections in one process (`tls.connect({ socket })`, another name, server keeps its side open): on `main` 1 of 5 handshakes completes, and the client reports no error for it. On `main` with the source change of #43957, 5 of 5 complete with no error. - #43962 sends a client's FIN after its ClientHello. It contains this PR's commits. - With #43957 only the test file conflicts: both PRs insert a block. Keep both. **Where the native check came from** - #31339 added the native name check for all clients. - #32359 proposed to remove it and was closed for #33755. #33755 added `DEFERS_SERVER_IDENTITY`: the check stayed enforced for `Bun.connect`, and for node:tls it was computed but not enforced. It took node:tls sockets out of `reject_unauthorized` and out of the error argument. - #42181 then added the guard for "failed after our own FIN", which is the same pair as "computed, another name". - #43863 says "Each connection has one server name check", and lists node:tls as "checked after the handshake, in JS". - This PR is the node:tls half of #32359. It does not touch the check for `Bun.connect`. - #43865, #43924 and #43947 are the fixes of the chain check in the same test file. **What the client handler gets from the fd engine** (`packages/bun-usockets/src/crypto/openssl.c`) `on_handshake` calls the handler with `(socket, flag, error)`. For a node:tls client: | Case | Before | Now | |---|---|---| | Handshake completed, chain and name good | `true, null` | `true, null` | | Handshake completed, chain good, another name | `false, null` | `true, null` | | Handshake completed, chain bad | `true, X509 error` | `true, X509 error` | | Chain refused inside the handshake | `false, X509 error` | `false, X509 error` | | Handshake failed after this side's FIN | `false, null` | `false, null` | | Handshake failed with a TLS reason | `false, EPROTO` | `false, EPROTO` | | The peer closed before the handshake finished | `false, ECONNRESET` | `false, ECONNRESET` | - Row 2 and row 5 were the same pair. The guard that #42181 added for row 5 also caught row 2 once the client had ended. - With no `end()`, row 2 already reached `checkServerIdentity`, because the guard tests `writableFinished`. So a client that does not end behaves as before. - `Bun.connect` and `upgradeTLS` sockets do not carry `DEFERS_SERVER_IDENTITY`. Their flag is `authorized`, as documented. **Rows that this PR does not change** The engine for a Duplex, a named pipe and TLS inside TLS (`SSLWrapper`, `src/uws/lib.rs`) reports no TLS reason. A failed handshake arrives as `(false, null)` after a verified chain and as `(false, X509 code)` otherwise. `onClientHandshake` reads both as an established session unless the client rejects the code. Measured on this PR with a client over a Duplex that does not call `end()`: | The peer answers the ClientHello with | `rejectUnauthorized` | `main`, Bun 1.4.2 and this PR | Node v26.3.0 | |---|---|---|---| | a fatal `handshake_failure` alert | `true` | `error UNABLE_TO_GET_ISSUER_CERT, close` | `error ERR_SSL_SSL/TLS_ALERT_HANDSHAKE_FAILURE, close` | | a fatal `handshake_failure` alert | `false` | `secureConnect authorized=false authError=UNABLE_TO_GET_ISSUER_CERT`, `end` | `error ERR_SSL_SSL/TLS_ALERT_HANDSHAKE_FAILURE, close` | | bytes that are not TLS | `false` | `secureConnect authorized=false authError=UNABLE_TO_GET_ISSUER_CERT`, `end` | `error ERR_SSL_WRONG_VERSION_NUMBER, close` | | a `close_notify` alert | either | no event | `end, error ECONNRESET, close` | - These rows are older than this PR: Bun 1.4.2 prints them too. The native socket is marked unusable after a failed handshake (`transport_unusable` in `on_handshake`). - Owners: #32929 (the engine reports the fatal alert over a Duplex), #44223 and #44021 (a refused renegotiation). - #44422 makes a handshake that did not complete terminal in `onClientHandshake`, as it is in the server handler. This PR is the step before it: while `(false, null)` could be a completed handshake, that arm could not go. It stays out of this PR so that this PR can land, or be reverted, alone. **What the native handle of a node:tls client reports** (trusted chain, another name, `rejectUnauthorized: false`, measured) | Value | `main` | This PR | |---|---|---| | `socket.authorized` | `false` | `false` | | `socket.authorizationError` | `ERR_TLS_CERT_ALTNAME_INVALID` | `ERR_TLS_CERT_ALTNAME_INVALID` | | `socket._handle.authorized` | `false` | `true` | | `socket._handle.getAuthorizationError()` | `ERR_TLS_CERT_ALTNAME_INVALID` | `null` | - The native check for these sockets had three effects on `main`: the flag in row 2 above, and the two internal values. - The in-handshake check (`server_identity`) already left node:tls sockets out. Both sites now agree. - `Flags::HOSTNAME_MISMATCH` has no reader on `main`. This PR does not remove it. - The hunk that stops the native check came from an optional finding of an automated review. No person has reviewed it yet. **Measured** (Linux x64, debug builds, Node v26.3.0, server in its own Node process, 40 s watchdog) `tls.connect({ socket })` on a connected socket, then `end()`. The chain is trusted, the certificate is for another name, `rejectUnauthorized: true`: | Server | TLS | Node | `main` (d115f54) | This PR | |---|---|---|---|---| | keeps its side open | 1.3 | `finish, error ERR_TLS_CERT_ALTNAME_INVALID, close` | `finish`, never exits | same as Node | | ordinary | 1.3 | `finish, error ERR_TLS_CERT_ALTNAME_INVALID, close` | `finish, end, close`, no error | same as Node | | keeps its side open | 1.2 | `finish`, never exits | `finish`, never exits | same as Node | | ordinary | 1.2 | `finish, end, error ECONNRESET, close` | same as Node | same as Node | - `end()` in the same tick and `end()` one `setImmediate` later give the same lines. - In the new tests the handshake completes after the client's `end()` under TLS 1.2 and over a Duplex as well. There `main` delivers `secret-banner` to a client with `rejectUnauthorized: true`. - A client that passes its own `checkServerIdentity` is asked: one test asserts the name that it gets, and `authorized=true` when it accepts. **Still open, the engine** - Each line of the table above is the first connection of its process. Five such connections, one after the other in one process, against a server that keeps its side open: with this PR the first reports and the other four print `finish` only. `main` does the same when the name is good. The flight that the first socket seals after its FIN takes the event loop's one spill slot and never leaves it. #43957 is open for that. - `tls.connect(port)` followed at once by `end()` still sends its FIN before its ClientHello, so no handshake runs there. #43962 changes that order. - #43957 is open for the spill slot. Measured with its source change on this PR: all five connections report, for another name and for a good name. - A handshake that fails after `end()` with no certificate still reports nothing. The tests of #42181 and #43947 for that case pass. **Tests** - 19 new tests against `main`: the name check after `end()` over a Duplex, over TCP behind a record proxy (TLS 1.2 and 1.3) and on a connected `net.Socket` (3 each), `end()` and `end("")` in the turn of `tls.connect()` over a socket that is still connecting and over a Duplex (6), and a resumed session (1, Bun only). - 7 of them are the commit of another branch (`robobun/baba0385/tls-early-end-hostname-check`), taken as it is. The resumed-session test now asserts `isSessionReused()`. - `main` (4b02e10) fails 18 of the 19. The one that passes is `end("")` over a Duplex. **Suites** (this machine ran at a load average of 200 to 800) - On this head: `node-tls-duplex-end-verify` (50 of 50), `node-tls-connect` (121), `tls-reject-before-client-cert` (121), `node-https-agent-checkserveridentity-reuse` (30), `renegotiation` (21), `node-tls-wrapped-socket-close` (15), `node-tls-connect-hostname-verification` (11), `node-tls-upgrade` (5), `node-tls-raw-end` (4), `node-https-checkServerIdentity` (4). - On the head before the rebase: 14 vendored Node tests that use `checkServerIdentity` or the name error, `fetch.tls` (61). `socket.test.ts`, `node-tls-cert` and `node-tls-server` had only failures that `main` has on this machine too (timeouts of child processes, and one test that needs `www.example.com`). - Not run on this machine: macOS, Windows. </details>
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Review comments at @test/js/node/tls/node-tls-duplex-end-verify.test.ts:
- Around line 395-455: Update connectAndEnd so its secureConnect promise rejects
if the client closes before emitting secureConnect, allowing the TLS 1.3
handshake failure to fail promptly. Suppress the expected rejection from the
intentionally unfinished TLSv1.2 client created as first.
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| test("a TLSv1.3 client that end()s finishes its handshake while a TLSv1.2 client that did the same stays open", async () => { | ||
| const server = tls.createServer({ key, cert }, socket => socket.on("error", () => {})); | ||
| server.on("tlsClientError", () => {}); | ||
| const clients = []; | ||
| const forwarded = []; | ||
| const { port, close } = await behindProxy( | ||
| server, | ||
| (downstream, upstream) => { | ||
| const client = clients.at(-1); | ||
| const flightForwarded = forwarded.at(-1); | ||
| let sawClientHello = false; | ||
| let clientEnded = false; | ||
| const held = []; | ||
| eachRecord(downstream, record => { | ||
| upstream.write(record); | ||
| if (sawClientHello) return; | ||
| sawClientHello = true; | ||
| client.end(); | ||
| }); | ||
| downstream.on("end", () => { | ||
| clientEnded = true; | ||
| for (const chunk of held.splice(0)) downstream.write(chunk, flightForwarded.resolve); | ||
| }); | ||
| upstream.on("data", chunk => { | ||
| if (clientEnded) downstream.write(chunk, flightForwarded.resolve); | ||
| else held.push(chunk); | ||
| }); | ||
| }, | ||
| { allowHalfOpen: true }, | ||
| ); | ||
| const connectAndEnd = maxVersion => { | ||
| const events = []; | ||
| const client = tls.connect({ | ||
| port, | ||
| host: "127.0.0.1", | ||
| servername: "agent1", | ||
| rejectUnauthorized: false, | ||
| maxVersion, | ||
| }); | ||
| clients.push(client); | ||
| forwarded.push(Promise.withResolvers()); | ||
| const secureConnect = new Promise(resolve => client.on("secureConnect", resolve)); | ||
| client.on("secureConnect", () => events.push(`secureConnect authorized=${client.authorized}`)); | ||
| client.on("error", () => {}); | ||
| return { events, secureConnect }; | ||
| }; | ||
| try { | ||
| const first = connectAndEnd("TLSv1.2"); | ||
| await forwarded[0].promise; | ||
| await pendingReadsDone(); | ||
| const second = connectAndEnd("TLSv1.3"); | ||
| await second.secureConnect; | ||
| assert.deepStrictEqual( | ||
| { first: first.events, second: second.events }, | ||
| { first: [], second: ["secureConnect authorized=false"] }, | ||
| ); | ||
| } finally { | ||
| for (const client of clients) client.destroy(); | ||
| close(); | ||
| } | ||
| }); |
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🩺 Stability & Availability | 🟡 Minor | ⚡ Quick win
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Add a close rejection to the second client.
If the TLS 1.3 client closes before secureConnect, second.secureConnect remains pending. The test runner can then wait until its timeout instead of reporting the handshake failure. Reject on close, and suppress the expected rejection from the intentionally unfinished first client during cleanup.
Suggested fix
- const secureConnect = new Promise(resolve => client.on("secureConnect", resolve));
+ const secureConnect = new Promise((resolve, reject) => {
+ client.on("secureConnect", resolve);
+ client.on("close", () => reject(new Error(`${maxVersion} closed with no secureConnect`)));
+ }); const first = connectAndEnd("TLSv1.2");
+ first.secureConnect.catch(() => {});
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only still-valid issues, skip the rest with a brief reason, keep changes
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Review comment at @test/js/node/tls/node-tls-duplex-end-verify.test.ts around
lines 395 - 455:
Update connectAndEnd so its secureConnect promise rejects if the client closes
before emitting secureConnect, allowing the TLS 1.3 handshake failure to fail
promptly. Suppress the expected rejection from the intentionally unfinished
TLSv1.2 client created as first.
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4 participants
Follow-up to #43947, which is merged. Rebased on main.
Problem
shutdown()orend()during a handshake the socket still seals handshake records.us_socket_raw_writesends nothing after a FIN, sossl_flush_write_batch(packages/bun-usockets/src/crypto/openssl.c) parks them as a spill that can never drain.us_internal_ssl_closewaits for that spill, so the socket never closes. The spill holds the loop's one spill slot, so the next half-closed handshake never finishes.socket.shutdown(), node:tls since tls: end() and destroySoon() before the handshake completes now send the FIN #42181 (not released).Fix
ssl_flush_write_batchand the unbatched path ofBIO_s_custom_writedrop records that the socket can never send.us_internal_socket_can_raw_write, gates the raw writes, the raw shutdown and both drops.Background
Downsides
.text: 58154908 to 58153884 B. Each flush costs 1 more direct call.Notes
Cases, each test run alone, on the head of #43947 before its merge (771b423) and with this change
Each socket calls
shutdown()orend()while its handshake runs. The peer keeps the connection open.Bun.listen,requestCert,rejectUnauthorized: true, TLS 1.2, untrusted clienthandshake(true, authorized=false, error), the socket never closesBun.connectclients, TLS 1.3closenever firesBun.connectclient, TLS 1.2, ended after the server's first flightclosenever fireshandshake(false), closeBun.connectclient that writes to a second TLS socket from its handshake callbackclosenever firestls.connectclients, the first (TLS 1.3 or TLS 1.2) stays opensecureConnecttls.createServer, TLS 1.2,end()in the handshake, untrusted client (control)tls.connectsockets after one such handshake in the same processRun in one process, more tests fail on #43947 than the table shows: a test that times out leaves the socket that holds the spill slot. That is also the only way in which
TLS 1.3 client sees 'end', not ECONNRESET, when the server tears down right after rejecting its certificate (#40653)failed. No CI run has shown the lost batching.The two-client probe gives the same result on the released 1.4.2 (
1.4.2+744846f84): the second client never reports its handshake.Mechanism
ssl_flush_write_batchsends them. After a FINus_socket_raw_writereturns 0. The flush parked all of it as a spill and took the spill slot. A spill drains from the writable event, and a socket that sent its FIN gets none.us_internal_ssl_closedefers a close with code 0 or 2 while the socket has a spill.hs_batchinginus_internal_ssl_on_data,batchinginus_internal_ssl_write). With the slot taken,BIO_s_custom_writewrites each record at once. After a FIN that write returns 0, the BIO asks for a retry, andSSL_do_handshakeanswersSSL_ERROR_WANT_WRITEuntil the socket closes.ssl_drain_spill. The first two now drop.ssl_drain_spillhas no guard on purpose:us_internal_ssl_shutdowndefers the FIN behind a spill, and a close releases the spill, so a socket that sent its FIN has no spill to drain.Why a drop is correct
us_internal_ssl_writerefuses application data after a FIN, andssl_handle_shutdownsends no close_notify after one. So only handshake records and alerts reach the new branches.Not in this PR
sendthat the kernel refuses withECONNRESETorEPIPEstill parks a spill. That needs the error of the raw write (tls: report a rejected send() as a write error instead of a clean close #42336, usockets: close a TLS socket whose send() keeps failing instead of spinning the writable dispatch #34510), not the state of the socket.allowHalfOpensocket that shut down during its handshake stays open after the peer's close_notify until the peer's FIN (since 1.4.1, tls: do not fail a pending write when the peer half-closes cleanly #40384). Main does the same, and it does not reach the new branches.end()from the'connect'listener sends the FIN before the ClientHello. Node sends the ClientHello first.Self-review
Rejected, with the reason:
afterAllnow releases what a timed-out test left, so the tests after the block are not affected.Measurements
Call counts are gdb breakpoint hit counts on debug builds with the debug info stripped. Sizes are from release builds of both trees.
Bun.listen/Bun.connectconnections:SSL_do_handshake600 and 600,BIO_s_custom_write700 and 700,ssl_flush_write_batch300 and 300,bsd_send600 and 600,bsd_recv600 and 600,us_internal_socket_close_raw200 and 200..text: 58154908 to 58153884 B (size -A). Strippedbun: 80844320 B both.ssl_flush_write_batchgrows from 214 to 254 B and is no longer inlined into its callers:BIO_s_custom_write683 to 512 B,us_internal_ssl_close1195 to 999 B,us_internal_ssl_on_data2651 to 2240 B,us_internal_ssl_shutdown608 to 412 B. So each flush is one direct call more in a release build, 3 per healthy connection pair.us_socket_raw_write178 B,us_socket_raw_writev356 B andus_internal_socket_raw_shutdown85 B before and after.us_mallocof its spill.Tests
test/js/bun/net/socket.test.ts: 8 new tests, 17 with "while the handshake runs" in the name. Run alone on tls: our own FIN does not fail a handshake that is still running #43947, 7 of the 8 fail, and the trusted TLS 1.2 client is the control.test/js/node/tls/node-tls-duplex-end-verify.test.ts: 3 new tests. Run alone on tls: our own FIN does not fail a handshake that is still running #43947, 2 fail, and the TLS 1.2 server is the control. Node v26.3.0 passes 34 of 34 (node --test).test/js/node/tls/node-tls-connect.test.ts: 1 new test, the one-segment flight. It fails on tls: our own FIN does not fail a handshake that is still running #43947 with 3 chunks for each connection.test/js/node/tls/andtest/js/bun/net/together (728 tests): no failure is only on this change. Failures on the base too:SNICallback runs even when the requested servername matches the bind hostname,should not call drain before handshake, and tests that wait for a garbage collection.should not call drain before handshake. Each of them fails on main on the test machine too. Before that rebase, on e375701, the two directories had 765 tests. 6 fail, the same 6 as on tls: our own FIN does not fail a handshake that is still running #43947 at that base. In one process, tls: our own FIN does not fail a handshake that is still running #43947 at that base fails 8 of the 17 tests with "while the handshake runs" in the name, and the one-segment test.test-tls-*,test-https-*,test-http2-*andtest-net-*files: 660 pass, and the 3 that fail do so on tls: always report the certificate verdict of a finished handshake #43924 too. This is a check for regressions only: no vendored file changes its result with this PR.