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fix(common-http): pin validated DNS answers at connect time - #14474
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… SSRF The image-diffusion handler passed the client-supplied input_reference straight through as the generator's image_path, so a client could point it at an arbitrary local file (path traversal / LFI) or an internal URL (SSRF). Validate it first via the existing url_validator: local paths are confined to DYN_MM_LOCAL_PATH with traversal rejected, and URLs are blocked from resolving to internal / non-public addresses. Behavior note: local I2I references now require DYN_MM_LOCAL_PATH to be set to the allowed directory. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Signed-off-by: nnshah1 <neelays@nvidia.com>
…are helper Video (I2V) had the same unvalidated input_reference -> image_path passthrough as image diffusion. Promote the validation to a shared validate_media_reference in url_validator (returns a plain path for local refs, SSRF-guards URLs) and use it from both the image and video diffusion handlers. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Signed-off-by: nnshah1 <neelays@nvidia.com>
WalkthroughThe change adds connect-time SSRF filtering to the aiohttp client. ChangesConnect-Time SSRF Protection
Priority: ➖ Normal Estimated code review effort: 3 (Moderate) | ~20 minutes Merge Risk: 🔵 Low · up to Proxy-enabled deployments could interpret the new DNS-rebinding backstop as covering proxied media fetches when the proxy resolves the origin instead. Document the required proxy or network-layer enforcement before merge. 🚥 Pre-merge checks | ✅ 4 | ❌ 1❌ Failed checks (1 warning)
✅ Passed checks (4 passed)
Full details: Docstring CoverageExplanation Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 18 functions across 5 files. (1 skipped: 1 unsupported.)
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In `@components/src/dynamo/common/http/aiohttp_client.py`:
- Line 69: Update the aiohttp client configuration around TCPConnector and the
associated session creation to disable environment-derived proxy routing for
SSRF-protected fetches, ensuring trust_env is false while retaining
BlocklistResolver protection. Add a rebinding test that enables HTTP_PROXY and
verifies attacker-controlled origins cannot bypass the blocklist.
In `@components/src/dynamo/common/http/httpx_client.py`:
- Around line 55-57: Update both fetch paths around resolve_allowed_ip to catch
SsrfBlockedAddress and translate it into HttpConnectionError, preserving the
HttpClient unified error contract before request handling; alternatively
centralize the same translation in _PinningTransport.
- Line 64: Create a separate outbound request before calling
super().handle_async_request(), apply the pinned IP host only to that copy, and
leave the caller-owned request URL unchanged so redirect resolution retains the
original hostname.
In `@components/src/dynamo/common/tests/http/test_ssrf_resolver.py`:
- Around line 110-112: Update
test_resolve_allowed_ip_returns_public_literal_unchanged to stub the lookup
boundary so any unexpected DNS lookup fails immediately, while preserving the
existing assertion that the public IP literal is returned unchanged.
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file:// URIs are percent-encoded, but the path was passed to validate_local_path literally, so a valid reference like file:///media/my%20image.png was checked as 'my%20image.png' and rejected. Unquote the file:// path (bare paths stay literal). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Signed-off-by: nnshah1 <neelays@nvidia.com>
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Static review of the exact PR head. No build or tests were run.
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Thanks @rmccorm4 — this was the right call. Reworked to mirror the Rust reference (reqwest httpx — removed the URL-rewriting pinning transport (addresses the pool-keying/TLS-isolation P1, the request-mutation/relative-redirect P2, the SNI-inheritance P2, the Happy-Eyeballs P2, the DNS-outside-connect-budget P2, and the explicit-transport-disables-env-proxy P2). httpx has no DNS-resolver hook, so faking it at the URL layer was the root cause. On the httpx backend we now rely on the pre-check + per-hop redirect revalidation already in aiohttp (default) — kept the Proxy (P1) — real, and identical in Rust. The resolver governs direct connections only; behind an egress proxy the proxy resolves the origin, so the resolver can neither protect it nor should it block the (often private) proxy address. The Rust client has the same property (reqwest honors env proxies and doesn’t govern proxied-origin DNS). I’ve documented this as a network-layer enforcement boundary for now. Open decision: for SSRF-protected media fetches, do we (a) disable proxy so the resolver governs every connection, or (b) keep proxy support and require SSRF enforcement at the proxy? Happy to align Rust + Python on whichever we pick. Per-call policy (P2): the shared connector is deliberately keyed to the env baseline — a per-request Separately: since httpx is the only backend without a resolver hook, one clean follow-up is to consolidate to aiohttp-only (it’s the default; httpx is a The redirect-SSRF P1 on #14435 is a separate, valid issue (the diffusion generator fetches URLs itself) — addressing that on that PR by fetching through the policy-aware client and passing a local path. |
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Follow-up: I opened #14563 to consolidate the HTTP client to aiohttp-only and remove the httpx backend entirely. Rationale is the same thread as here — httpx has no DNS-resolver hook (so the connect-time SSRF pin cant be done without the URL-rewrite hacks you flagged), plus it hit Once #14563 lands, the "httpx relies on pre-check only" caveat in this PR is moot — there is no httpx backend, and the aiohttp On "could httpx be fixed correctly?" — yes, but not at the URL layer: the right hook is a custom |
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:robot_face: Restacked this on top of #14563 (aiohttp-only consolidation) per discussion — the branch was rebased so its diff is now only the aiohttp resolver (3 files); the httpx backend is deleted in the base, so all the httpx URL-rewrite findings are gone by construction. The aiohttp resolver logic is unchanged from the last revision. (Rebase = force-push; @coderabbitai full review if a fresh pass is wanted.) |
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✅ Action performedFull review finished. |
rmccorm4 P1: validate_media_reference blocks the initial URL, but a URL was still handed to the DiffGenerator, which fetches it and follows redirects with only a scheme check — so an allowed origin could 302 to an internal address (redirect SSRF), separate from DNS rebinding. Add local_media_reference(): a URL is fetched through the policy-aware client (which revalidates every redirect hop) into a temp file, and the generator is handed that trusted local path; local references pass through unchanged. Wire both the image-diffusion and video-generation handlers to it via an AsyncExitStack so the temp file is cleaned after generation. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Signed-off-by: nnshah1 <neelays@nvidia.com>
Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com> # Conflicts: # components/src/dynamo/sglang/request_handlers/image_diffusion/image_diffusion_handler.py
validate_local_path embeds the client-supplied path in three of its messages. Those messages are returned to the caller and written to a log line, and input_reference has no length limit, so a 200 KB reference produced a 200 KB error string at every sink (measured: len(str(exc)) == 200023). describe_media_source already exists for exactly this, but lives in multimodal.media_source, which cannot be imported from here -- its package __init__ pulls in torch. Move it next to the validators and re-export it from media_source, which is where callers import it from. The label is a no-op below 120 characters, so existing messages are unchanged; the configured allowed directory is dropped from the "outside the allowed directory" message, since callers surface that text to the client and the path is deployment detail. Two smaller fixes in the same file: - An embedded NUL makes Path.resolve() raise ValueError, not OSError, so it escaped validate_local_path untyped. %00 reaches it as a real NUL now that file:// paths are percent-decoded (92201a2), and callers key their 4xx-vs-5xx decision on UrlValidationError -- image_loader.py and video_loader.py both say so in comments. Measured before/after on file://<dir>/x%00.png: UrlValidationError -> ValueError -> back to UrlValidationError. - validate_media_reference gained validate_media_url's empty-input guard. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
…ffer Nothing in the HTTP facade bounded a response body, which only became reachable for diffusion once this PR moved the download here. SGLang's get_image_bytes sends an http(s) image_path through download_remote_media, which streams under media_url_max_file_size_mb (default 64 MiB, sglang 0.5.18 server_args.py:2804); handing the generator a local path instead takes its plain open() branch, where that limit never runs. Measured on the PR as it stood: a 64 MiB body became a 64 MiB temp file with peak RSS going 72 -> 214 MB. fetch_bytes takes max_bytes and both backends stream through collect_capped, which counts as the body arrives. Two things it has to do that a simpler check does not: a declared Content-Length is attacker-controlled and absent on a chunked response, and aiohttp's read(n) returns *at most* n bytes -- measured returning 65328 for read(1 MiB + 1) -- so a single capped read sees a short body and passes it. Exceeding the cap raises UrlValidationError, matching how the redirect cap in the same loop already reports a verdict on a client-supplied URL. httpx needs stream=True to stop before buffering, so its response fakes move from client.get to build_request/send; the aiohttp fake grows the response.content reader the cap streams from. Verified against a real local server on both backends, declared and chunked, with the SSRF redirect control still blocking: aiohttp 64 MiB decl. -> UrlValidationError, peak RSS 72->74 MB aiohttp 64 MiB chunked-> UrlValidationError, peak RSS 74->78 MB httpx both -> UrlValidationError, peak RSS flat 302 -> 169.254.169.254 -> UrlValidationError (IP literal blocked) max_bytes defaults to None, so every existing caller is unchanged. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
The module promises callers "a trusted local path, never a URL", and
three things broke that promise.
- validate_url returns data: URLs unchanged, so a data: reference fell
through to `yield resolved` and the generator was handed the URI as
image_path. Measured: local_media_reference("data:image/png;base64,...")
yielded the URI itself, os.path.exists() False. Rejected now, with the
reference described rather than echoed -- a data: URI is the payload,
so a 200 KB one would otherwise land whole in the error.
- The temp-file suffix came from the client's URL path with no bound. A
300-character extension reached mkstemp and raised
"OSError: [Errno 63] File name too long: /var/folders/.../tmpXXXX.aaa…",
an unhandled type carrying the server's temp directory to the caller.
Only a short alphanumeric extension survives now; anything else is
dropped, which also keeps a percent-encoded separator out of the name.
- The download is capped at MAX_MEDIA_BYTES (64 MiB, matching the SGLang
default this path used to go through).
Also corrects the "Lazy import" comment: importing this module already
executes the http package __init__, so nothing is deferred. The import
stays inside the function for the reason that is actually true -- it is
the seam tests monkeypatch.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
Merging main brought in #13000, which stopped the image handler swallowing exceptions into a 200 with an empty body: it now lets them reach the runtime, where InvalidArgument becomes a 400 carrying the reason and everything else becomes a sanitized 500. UrlValidationError is a plain ValueError, so a rejected input_reference took the second path and the client learned nothing about its own bad request. It also broke this PR's own test, which still expected the yielded {"error": ...} payload -- verified failing at the merge commit before this change. Map UrlValidationError to InvalidArgument at the call site. Transport failures (timeout, 404) are left alone: an unreachable origin is not necessarily the caller's fault. The video handler keeps its own error channel (VideoGenerationResponse has an error field, so it is not silent); giving it #13000's treatment is a separate change. Tests: the rejection test now asserts the 400, and a new one asserts the client-visible message stays bounded when the reference does not. The video handler had no test at all, so the shared validation could have been dropped from it alone with every test still green -- covered now, and confirmed by removing the validation and watching three of the four fail. Both "resolved path" assertions were rewritten to send a "sub/.." segment, because an already-normalized tmp_path resolves to itself on Linux and the assertion held even with no resolution. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
#14435 landed on main as 7a77a5d, so the stack this branch sat on is now upstream. Five paths conflicted, and four of them are purely #14435's payload where this branch carries the older stacked copy and main has the final -- base.py, media_reference.py, test_media_reference.py, test_http_facade.py all take main's, which includes the later review fixes the branch predates (exc.strerror, the data-URI bound, DYN_MM_MAX_FILE_SIZE_MB, the aiohttp comment rewording). aiohttp_client.py is the one with real content on both sides: main's version carries #14563's timeout/session work and #14435's collect_capped/max_bytes, this branch adds the BlocklistResolver wiring. Took main's and re-applied the wiring verbatim. This branch's own contribution is a single commit, 6270823, touching README.md, __init__.py, _ssrf_resolver.py, aiohttp_client.py and test_ssrf_resolver.py; everything else in its history is #14435's. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
…backstop Three problems in the resolver as written, all found by review and confirmed by running it. An egress proxy on a private address was filtered out. The session runs with trust_env=True, so with HTTP_PROXY set the connector dials the proxy, and it is the proxy's own address that reaches this resolver -- the origin is resolved by the proxy, out of our sight. Measured before this change: HTTP_PROXY at a private host turned every fetch into ClientConnectorDNSError, so a deployment behind a corporate proxy had to choose between broken egress and setting DYN_MM_ALLOW_INTERNAL=1, which disables the backstop entirely. The configured proxy is now exempt; measured after, the same request reaches the proxy while the rebind case still blocks. BlocklistResolver fell back to None if the aiohttp import failed, and the call site skipped wiring the resolver when it was None -- a security backstop that silently disappears. aiohttp_client.py imports aiohttp at module scope, so the fallback was unreachable anyway. Removed both, which also let mypy see the class and surface four wrong annotations: resolve() returns list[ResolveResult] and takes socket.AddressFamily, per aiohttp's AbstractResolver. The blocked-host message interpolated the raw hostname, which is caller-supplied and unbounded, on a path where it reaches an error response and a log line through the facade's connection error. Bounded with describe_media_source, as every other message on this path already is. Documented the scope in README.md and __init__.py: the backstop governs direct connections, proxied fetches are the proxy's or the network's to enforce, and aiohttp never calls a resolver for an IP literal so those stay validate_url's job. Tests cover the proxy exemption, a non-proxy host still being filtered, and the bounded message. One note for whoever reads them: aiohttp's proxies_from_env() prefers the lowercase http_proxy, and an image that already sets one will override an uppercase-only setenv -- the tests clear both. 113 pass in common/tests/http; ruff and mypy clean. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
Building the connector through a dict(...) of numeric kwargs made mypy infer dict[str, float], so both assigning the resolver into it and splatting the result into TCPConnector failed -- 12 errors, all in this file, on the dynamo-runtime / mypy job. Pass the arguments directly. Also add the two tests that would have caught a dropped resolver=: nothing asserted _build_session installs it, so the resolver's own unit tests stay green either way. Both fail with the wiring removed and pass with it; the other 113 are unaffected in both directions. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
The marker report stubs "aiohttp" but not its submodules, and a stubbed parent exposes none. The connect-time resolver imports aiohttp.abc, aiohttp.helpers and aiohttp.resolver, so every test whose import graph reaches dynamo.common.http failed to collect -- 49 collection errors, and the pre-commit job red. Adding the three submodules takes the hook from 49 collection errors to 0 and the collected total from 4528 to 5799 tests; removing them again reproduces the exact ModuleNotFoundError from the job log. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
aiohttp wraps the resolver's OSError in ClientConnectorDNSError and renders strerror, not str(exc). The one-argument OSError form leaves strerror as None, so the caller received "Cannot connect to host ... [None]" and the reason was dropped at the one place an operator reads it. The message was already bounded for this path, and none of it arrived. Measured before and after in the dynamo-runtime-test image on the AMD64 box. Before: "... ssl:default [None]". After: "... ssl:default [host localhost resolves only to blocked IPs]". The new test asserts both strerror and errno. It fails on the one-argument form and passes on the two-argument form, and the other 115 tests do not change in either direction. errno is EHOSTUNREACH by name because the number differs by platform: 113 on Linux, 65 on macOS. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
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Static latest-head re-review.
Three findings from review, all reproduced before changing anything. The connect-time resolver read only DYN_MM_ALLOW_INTERNAL, so a deployment that allows private addresses overrode a caller that asked for allow_private_ips=False. Measured with a simulated rebind: the strict request reached the private origin and returned its body. The connect-time flag is now the intersection of the deployment baseline and the request policy, so neither side alone can weaken the other. The client keeps one session per outcome, at most two. After the change the same strict request is blocked, and a permissive request still reaches the origin, which shows the block is the policy and not a broken probe. TCPConnector sets _resolver_owner=False for a resolver it did not create and closes only its own, so closing the session never closed ours. Measured: zero calls to BlocklistResolver.close() after session close. The client now holds each resolver and closes it after the sessions. _fetch_simple and _fetch_body_or_redirect take the policy so the backend can pick the connector. Both are abstract, so every implementer was re-audited: AiohttpClient is the only production one, and three test doubles took the new keyword. Each fix has a test that fails when that fix alone is reverted. 118 pass. Reported by rmccorm4. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
# Conflicts: # tests/report_pytest_markers.py
When a proxy applies, the connector dials the proxy and the proxy resolves the origin, so the origin hostname never reaches the connect-time check. Measured: the resolver saw only the proxy host, while the proxy received the absolute URI http://example.com/x.png. Recording that boundary in the README did not enforce it, so a rebinding origin still passed the first lookup and was dialed through the proxy unchecked. A policy-protected fetch that a proxy would carry now fails closed, naming DYN_MM_TRUST_EGRESS_PROXY. Setting it to 1 asserts that the proxy enforces destination policy, and the fetch proceeds. The gate does not run when DYN_MM_ALLOW_INTERNAL=1, which already permits private destinations. The gate asks aiohttp which proxy applies to that one URL rather than whether any proxy variable is set, so NO_PROXY is honored and a fetch that goes direct is never refused. Reverting that to a "any proxy configured" check fails test_no_proxy_exempts_a_host_from_the_gate; an earlier version of that test passed either way and pinned nothing, so it now asserts the helper directly. It raises HttpError, not UrlValidationError. This is an operator configuration fault rather than a verdict on the caller's URL, and media_connector re-raises UrlValidationError as a client error while falling back on ValueError. HttpError is neither, so it propagates. Tests clear the proxy environment in conftest. Without that, a developer machine or CI runner behind an ambient http_proxy fails tests unrelated to proxies; this machine has one, and it failed seven. This is a behavior change for deployments that rely on an ambient proxy today. They must set DYN_MM_TRUST_EGRESS_PROXY=1. Reported by rmccorm4. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
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Static latest-head re-review. No local build or tests were run.
… path Four findings from review, each reproduced before changing anything. The gate raised HttpError, and AudioLoader.load_audio and VideoLoader.load_video convert unknown exceptions into ValueError, which py_err_to_dynamo maps to InvalidArgument. Measured in the vllm-runtime-test image: an HttpError went in and builtins.ValueError came out, so audio and video clients received a 4xx for a deployment fault. My earlier reply claimed HttpError propagated; that held only for media_connector.fetch_image_async, not these two loaders. There is now an HttpConfigurationError subtype, and all three loaders preserve it. get_env_proxy_for_url does proxy-bypass discovery and .netrc reads. aiohttp calls it through asyncio.to_thread (client.py:777) for that reason, while the gate called it inline on the event loop for every protected hop. It is now awaited through asyncio.to_thread as well. Two pools can coexist, each with the full max_connections, so the total can reach twice the value that DYN_HTTP_MAX_CONNECTIONS described as a total cap. Measured: 100 and 100, aggregate 200. The help text now describes the cap per connect-time policy and names the condition. Note the second pool cannot appear in the default configuration, where the connect policy is always strict whatever a caller passes; both facts are now pinned by tests. A test built a session through _build_session, which does not register it, so client.close() closed the resolver and left the session open. Measured session.closed False after close. It builds through _get_session now and asserts closure. Each fix fails its own test when reverted alone, including the two loader tests run in the image on the AMD64 box. Reported by rmccorm4. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
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approving after self-review
| family: socket.AddressFamily = socket.AF_INET, | ||
| ) -> list[ResolveResult]: | ||
| hosts = await self._inner.resolve(host, port, family) | ||
| if self._allow_private_ips or host in self._proxy_hosts: |
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This exempts the hostname regardless of whether the connection is actually going through a proxy:
if self._allow_private_ips or host in self._proxy_hosts:
return hostsWith HTTPS_PROXY=http://proxy.review.test:3128 and NO_PROXY=proxy.review.test, a direct HTTPS request to that hostname on another port bypasses filtering. I reproduced this with the default strict policy: validation received a public DNS answer, connection-time resolution returned loopback, and the private test server received the request. Neither private-access permission nor proxy trust was enabled; the equivalent non-proxy hostname was blocked.
Can the exemption be confined to actual proxy connections, keeping direct/NO_PROXY origin lookups filtered even when their hostname matches a configured proxy? Please add this case alongside a successful trusted-private-proxy control.
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Thanks. #15780 fixes this (commit e704eec).
The exemption now applies only on connections that dial the proxy. A fetch that a trusted proxy carries runs on its own session. Only the resolver of that session exempts the proxy, and only at the proxy's own host and port. Direct fetches, including the ones that NO_PROXY covers, run on a session whose resolver exempts nothing.
I did not use one shared connector with a per-request flag, because aiohttp caches DNS answers per connector, keyed by (host, port). An exemption keyed on host and port alone still exempted a direct fetch to the proxy's own port.
test_proxy_connections.py has these tests:
- Your case, over HTTPS and over HTTP.
- A direct fetch to the proxy's own port.
- A direct fetch after a proxied fetch filled the DNS cache.
- A trusted private proxy that still works.
- The same host name with no proxy setting.
The direct-fetch tests and the cached-answer test fail on main and pass with the fix. The two controls pass on both.
| # No proxy for this URL, so aiohttp dials the origin and the | ||
| # connect-time check governs it. | ||
| return | ||
| raise HttpConfigurationError( |
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Please preserve HttpConfigurationError in TRT-LLM’s direct video-fetch path too. That path calls fetch_bytes() independently of the common VideoLoader, then its generic handler assigns:
status if isinstance(status, int) and status >= 400 else 400The new error has no status, so a valid video request through an untrusted configured proxy becomes HTTP 400. I confirmed HttpStatusError(status=400) with HttpConfigurationError as its cause.
Import the new exception in trtllm/multimodal_processor.py and preserve it before the generic handler:
except HttpConfigurationError:
raise
except Exception as e:
# existing fallback
...This is an illustrative fix; please add a processor-level regression test.
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Thanks, I reproduced this and fixed it in #15780 (commit 214eef9).
On main, process_openai_request raised HttpStatusError with status 400 and HttpConfigurationError as its cause. The request fetched https://93.184.216.34/v.mp4 with HTTPS_PROXY set and the proxy not trusted. The video path now re-raises HttpConfigurationError before the generic handler. The import line is the same as the one in #14373.
The new processor test, test_video_through_an_untrusted_proxy_is_not_a_client_error, drives the real shared client. It fails on main with the 400 and passes with the fix.
I also traced the other callers of fetch_bytes. None of them turns HttpConfigurationError into a 4xx.
One path still ends in a 400, and it is not specific to this error. A TensorRT-LLM prefill worker receives any exception from a separate encode worker as a ValueError (check_response_error in lib/bindings/python/rust/errors.rs). The frontend answers a ValueError with 400. I found this by reading the code, not in a running deployment, so I left it for a separate change.
Other callers, with the same untrusted proxy.
| Caller | Result |
|---|---|
local_media_reference |
raises HttpConfigurationError |
SGLang image diffusion, input_reference |
raises HttpConfigurationError |
SGLang video generation, input_reference |
yields status: "failed", as it does for every error |
| SGLang encode worker, both fetch sites | raises HttpConfigurationError, and generate re-raises it |
ImageLoader.load_image, AudioLoader.load_audio, VideoLoader.load_video |
raises HttpConfigurationError |
the three load_*_batch functions |
raises Exception with the message, which maps to 500 |
Signed-off-by: nnshah1 <neelays@nvidia.com> Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com> Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com> Co-authored-by: Dmitry Tokarev <dtokarev@nvidia.com> (cherry picked from commit 848206e) Conflict resolution for release/1.5.1: - tests/report_pytest_markers.py: This pick adds only the three aiohttp stubs of #14474 and their comment. The "aiohttp.test_utils" stub next to them on main comes from #14377, which release/1.5.1 does not have. Signed-off-by: Dmitry Tokarev <dtokarev@nvidia.com>
4 participants
nvbug/6544964
Summary
validate_urlresolves a hostname and checks the addresses it gets back. Theclient then resolves the same hostname again when it opens the connection. A
server that answers differently the second time is checked on one address and
dialed on another.
This change wires a resolver into the aiohttp
TCPConnector. The client nowresolves and filters once, then hands the connector the addresses it already
validated. The hostname still drives TLS SNI and certificate verification. The
resolver returns every address that passed, so aiohttp keeps its normal
multi-address fallback. The Rust frontend uses the same mechanism on reqwest's
dns_resolverinlib/llm/src/preprocessor/media/loader.rs.The connector may return private addresses only when the
DYN_MM_ALLOW_INTERNALdeployment baseline and the request policy both allowit, so neither side alone can weaken the other. The client keeps one session
per outcome, at most two, and closes each resolver itself, because aiohttp
closes only a resolver it created.
Scope
Two limits apply. The module docstring and the README record both.
A proxied fetch fails closed. The session runs with
trust_env=True. When aproxy applies, the connector dials the proxy, and the proxy resolves the origin
address out of this resolver's sight, so the check cannot govern the
destination. A policy-protected fetch that a proxy would carry is therefore
refused, naming
DYN_MM_TRUST_EGRESS_PROXY. Set that to1to assert that theproxy enforces destination policy itself and the fetch proceeds. The gate asks
aiohttp which proxy applies to that one URL, so
NO_PROXYis honored and afetch that goes direct is never refused. It does not run under
DYN_MM_ALLOW_INTERNAL=1, which already permits private destinations.This is a behavior change for a deployment that relies on an ambient proxy
today. Such a deployment must set
DYN_MM_TRUST_EGRESS_PROXY=1.An IP literal never reaches a resolver. aiohttp short-circuits literals in
TCPConnector._resolve_host. Literal addresses stay the job ofvalidate_url.Files
_ssrf_resolver.py: newBlocklistResolverandSsrfBlockedAddress, and the proxy exemption.aiohttp_client.py: wire the resolver onto the sharedTCPConnector.__init__.pyandREADME.md: record what the resolver covers and what it does not.test_ssrf_resolver.py: seven tests. They cover keep-the-rest, fail-closed, theallow_private_ipsbypass, the proxy exemption, a non-proxy host at the same address, the bounded message, and the reason reachingstrerror.test_aiohttp_client.py: two tests. One proves the connector carries the resolver. One proves a permissive per-call policy does not loosen it.tests/report_pytest_markers.py: stubaiohttp.abc,aiohttp.helpers, andaiohttp.resolverso the marker report can collect.Validation
Measured in the
dynamo-runtime-testimage on an AMD64 box, Python 3.12.3 withaiohttp 3.14.3, and again on macOS ARM64. Both give the same result.
A fetch to
http://localhost:PORT/x.pngexercises the resolver, becauselocalhostis a hostname and 127.0.0.1 is a blocked address. The per-callpolicy was
allow_private_ips=Truein both runs below.The second line is the control. The server works, so the block came from the
resolver, and the permissive per-call policy did not loosen it.
The proxy exemption, measured against a stub proxy on 127.0.0.1:
The third line shows the exemption is narrow. A host that is not the configured
proxy is still filtered at the same blocked address.
Unit tests and static checks:
pytest components/src/dynamo/common/tests/http/: 116 passed.resolver=argument and both wiring tests fail. Restore it and they pass. The other tests do not change in either direction.mypy --explicit-package-basesover the CI target set: 850 files, no error in any changed file.pre-commit run --all-files: exit 0. Without the three stub entries the marker report reports 49 collection errors.🤖 Generated with Claude Code