changePath cleared RawPath whenever it equalled url.Path, which
discarded a valid non-canonical percent-encoding produced by a
replacement. This compare `RawPath` against the default escaping of Path
instead.
quic-go defaults the `InitialPacketSize` to 1280 bytes. This is used for
the size of the payload plus UDP header. When quic-go creates its
initial handshake packet, it pads it to this size as an optimization
for the anti-amplification limit (which does not really apply to
Caddy's server connections).
Tailscale uses an MTU of 1280 (the minimum IPv6 MTU) because it is a
tunnel operating in unknown environments, possibly inside other
tunnels.
When wrapped in an IP header (either v4 or v6), the 1280 byte QUIC packet
constructed by quic-go exceeds the Tailscale MTU and gets dropped. This
makes it impossible to respond to an HTTP3 connection attempt over
Tailscale when using the default `InitialPacketSize`.
We explicitly set the `InitialPacketSize` to 1200 (its minimum) to support
HTTP3 connections over Tailscale and other low MTU connections.
Once the connection is established, quic-go can perform MTU discovery to
increase the packet size to the maximum supported by the connection, so
any throughput loss due to the lowered `InitialPacketSize` is
short-lived.
The random_choose selection policy is meant to implement
power-of-d-choices: sample d available upstreams uniformly, then pick
the least-loaded of that sample. The sampling loop, however, was not a
correct reservoir sample (Algorithm R): it never filled the first k
reservoir slots unconditionally, instead writing every candidate to a
random slot j = rand(i+1), which can evict an earlier candidate while
leaving another slot nil. It also derived j from the upstream's index
in the pool rather than from the number of available upstreams seen,
skewing the sample whenever unavailable upstreams precede available
ones.
As a result the reservoir frequently held fewer than min(k, available)
upstreams, so the least-load comparison often never happened. Most
notably, with two upstreams and 'random_choose 2' (the canonical
power-of-two-choices setup), half of all requests were routed to the
more-loaded upstream even when it was saturated and the other idle --
identical behavior to plain 'random'. The nil slots this leaves behind
were also the cause of the panic reported in #3810, which was patched
by skipping nils in leastRequests rather than by fixing the sampling.
Replace the loop with a standard Algorithm R reservoir sample over the
available upstreams: fill the first k slots, then replace a random slot
with probability k/n. Every available upstream is now sampled uniformly
and the reservoir always holds min(k, available) candidates.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Same obsolete two-argument check as the reverse_proxy one removed in
#7869: it referenced the long-removed inline status-code-replacement
syntax and pointed users at replace_status even when no status
replacement was involved. The generic check now rejects all
excess-argument cases with an accurate message.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* caddyhttp: normalize Windows path in path_regexp matcher, shared with path matcher
Apply the same Windows path normalization to MatchPathRE that MatchPath already had, and factor it into a shared normalizeWindowsPath helper so both matchers use one implementation.
Also strip trailing dots and spaces per path component (not only at the end of the whole path), matching how Windows resolves paths; this fixes the same gap in the path matcher too. Adds regression tests for both matchers.
See #5613.
* caddyhttp: normalize trailing dots/spaces in escaped-path branch too
The MatchPath escaped-path branch (taken when a matcher pattern contains
'%') only folded backslash separators via windowsEscapedPathSeparatorRepl;
it skipped the per-component trailing dot/space normalization now applied
on the decoded branch. On Windows this left a bypass: a matcher such as
`path /private%2f*` could be evaded by GET /private.%5csecret.txt, since
`private.` and `private` resolve to the same directory on NTFS.
Add normalizeWindowsEscapedPath, which trims trailing dots and spaces —
literal ("." / " ") and percent-encoded ("%2e" / "%20") — from every
component in raw/escaped space, splitting on both '/' and encoded '%2f'
separators while preserving them, and leaving "." / ".." for CleanPath.
Regression tests cover the literal and percent-encoded variants against a
'%'-containing matcher.
---------
Co-authored-by: thientd <thien.taduc@ninhthanh.com>
* caddyhttp: add url_pattern request matcher
Match requests against a URLPattern (https://urlpattern.spec.whatwg.org/),
supporting named groups, wildcards and regexp components beyond the path
matcher. Relative patterns match any origin; absolute patterns or base_url
scope to scheme and host.
Exposes a url_pattern CEL function and publishes captured groups as
{http.url_pattern.<component>.<group>} placeholders.
* caddyhttp: add Caddyfile adapt test for url_pattern matcher
* tracing: fix BatchSpanProcessor goroutine leak on config reload
When the `tracing` directive is enabled, each config reload leaks one
`go.opentelemetry.io/otel/sdk/trace.(*batchSpanProcessor).processQueue`
goroutine. On a server that reloads frequently (e.g. polling a remote
config source every few seconds) this accumulates into tens of thousands
of leaked goroutines over time.
A goroutine dump shows many identical stacks:
```
goroutine ... [select]:
go.opentelemetry.io/otel/sdk/trace.(*batchSpanProcessor).processQueue(...)
.../sdk/trace/batch_span_processor.go:327
go.opentelemetry.io/otel/sdk/trace.NewBatchSpanProcessor.func2()
.../sdk/trace/batch_span_processor.go:129
created by go.opentelemetry.io/otel/sdk/trace.NewBatchSpanProcessor
.../sdk/trace/batch_span_processor.go:127
```
`tracing` keeps a global, reference-counted `TracerProvider` so it can be
reused across reloads (`tracerProvider.getTracerProvider`). Caddy reloads
provision the new config *before* cleaning up the old one, so the counter
never drops to 0 and the provider is correctly reused — `Shutdown` is
never called, by design.
The problem is on the caller side in `newOpenTelemetryWrapper`:
```go
traceExporter, err := autoexport.NewSpanExporter(ctx)
...
tracerProvider := globalTracerProvider.getTracerProvider(
sdktrace.WithBatcher(traceExporter), // evaluated on every reload
sdktrace.WithResource(res),
)
```
`sdktrace.WithBatcher(e)` is `WithSpanProcessor(NewBatchSpanProcessor(e))`,
and `NewBatchSpanProcessor` **starts its `processQueue` goroutine eagerly at
construction time** — not when the option is applied. The option is built
on every `Provision` (every reload), but `getTracerProvider` only applies
it when it actually creates a new provider (`t.tracerProvider == nil`). On
the reuse path the option is silently discarded, so the just-started
BatchSpanProcessor goroutine is orphaned: it is never registered with any
provider and therefore never shut down. Result: one leaked goroutine (plus
a leaked exporter) per reload.
Defer construction of the exporter/batcher until a new provider is actually
needed. `getTracerProvider` now takes a `buildOpts` factory that is invoked
only on the create path, so nothing with a side effect is built on the
reuse path.
The reference counter is now incremented only after the provider is
successfully obtained, preserving the previous semantics where a failed
exporter creation did not affect the counter.
- `Test_tracersProvider_buildOptsOnlyOnCreate` — asserts `buildOpts` runs
exactly once across one create + five reuses (the regression guard).
- `Test_tracersProvider_buildOptsError` — asserts that on a build error the
provider stays nil and the counter is not incremented.
- Existing tracing tests updated for the new signature and still pass.
Verified manually with a reload loop: before the fix, 50 reloads leaked 50
`processQueue` goroutines; after the fix, 0 are leaked while the provider is
still reused (counter stays at 1).
* add test for buldOpts error path
---------
Co-authored-by: Zen Dodd <mail@steadytao.com>
* rewrite: scope keyed query replace to its named key
* rewrite: cover keyed search_regexp query replace in test
* rewrite: provision query replace test via Provision path
Multiple `hide` subdirectives in a file_server Caddyfile block silently overwrote each other, so only the last one took effect. Append to the list instead, so repeated entries accumulate and imported snippets can compose with site-specific hides.
* test: add failing tests for intercept replace_status (#7805)
Add integration tests that verify replace_status actually substitutes
the HTTP status code sent to the client. Currently these tests fail
because replace_status is silently a no-op due to value-receiver
boxing and shouldBuffer returning false.
Tests added:
- TestInterceptReplaceStatusWithMatcher: 500 -> 200 with @err matcher
- TestInterceptReplaceStatusWithoutMatcher: 403 -> 200 unconditionally
- TestInterceptReplaceStatusNotMatched: 200 passes through unchanged
* fix: make intercept replace_status actually substitute the status code
Fix#7805: replace_status was silently a no-op because:
1. shouldBuffer returned false when a replacement status was set,
causing the original status to be streamed directly to the wire
2. The value-receiver WriteHeader method operated on a stale copy
The fix:
- shouldBuffer now returns true when replace_status matches, so
the response is buffered instead of streamed
- After next.ServeHTTP returns, if routes are nil (replace_status
only), write the substituted status and buffered body to the client
The interceptedResponseHandler.WriteHeader substitution branch is no
longer needed for this path since substitution happens post-ServeHTTP.
* refactor: remove dead WriteHeader method and resolved TODO
The value-receiver WriteHeader on interceptedResponseHandler was
unreachable dead code — the substitution is now handled post-ServeHTTP
via buffering. Remove it along with the TODO comment that noted
status code replacement was unfinished.
* style: apply nit suggestions from dunglas code review
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---------
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
* caddyhttp: restore allow_underscore_in_headers server option (#7808)
* caddyhttp: mark insecure_allow_underscore_in_headers as EXPERIMENTAL
* caddyhttp: replace underscore bool with expected_underscore_headers allowlist
* fix gofmt alignment in serveroptions.go
* caddyhttp: drop repeated allowlisted underscore headers
* caddyhttp: add tests for repeated-value drop and variant-drop logging
* reverseproxy: validate on weighted_round_robin policy
Validate that weighted_round_robin has a non-zero total weight.
This prevents configurations such as:
weighted_round_robin 0 0
from being accepted and causing a divide-by-zero panic during request handling.
* test: validation test on zero weight upstreams.
* test: provision called instead of totalweight setting
* reverseproxy: validate on negative upstream weights
* test: regression test on weighted_round_robin selection policy
* caddyhttp: add {http.request.proto_name} placeholder for spec-compliant protocol names
{http.request.proto} exposes Go's raw http.Request.Proto field which
returns HTTP/2.0 and HTTP/3.0 for HTTP/2 and HTTP/3 respectively.
These strings are non-standard since the specs define them as HTTP/2
and HTTP/3.
To preserve backward compat (especially CGI/FastCGI expectations),
{http.request.proto} is kept as-is. A new {http.request.proto_name}
placeholder is introduced that normalises the version string to the
spec-defined form:
HTTP/2.0 -> HTTP/2
HTTP/3.0 -> HTTP/3
all others returned unchanged
Closes#7734
* caddyhttp: Use ProtoMajor for proto_name normalization and update docs
---------
Co-authored-by: jalikajalika5 <105954036+jalikajalika5@users.noreply.github.com>
* reverseproxy: replace placeholders specified for sni while using http3
* add test for placeholder
* reverseproxy: replace placeholders specified for sni while using http3
* add test for placeholder
* reverseproxy: test HTTP/3 SNI host placeholder
---------
Co-authored-by: Zen Dodd <mail@steadytao.com>
* Patch GHSA-vcc4-2c75-vc9v in stripHTML
templates: fix funcStripHTML bypass via depth counter
The previous false-start approach allowed XSS bypass via inputs like <<>img src=x onerror=alert(1)> and failed on stacked angle brackets.
Replace the tagStart/inTag state machine with a depth counter that mirrors PHP strip_tags behaviour: each '<' increments depth, each '>' decrements it, and text is only emitted at depth zero. Quoted attribute values (both single and double) are tracked so '>' inside href values does not prematurely close a tag.
Signed-off-by: JM Sanchez <77505889+jmrcsnchz@users.noreply.github.com>
* Update tplcontext_test.go
Templates: expand TestStripHTML with attack path coverage
Signed-off-by: JM Sanchez <77505889+jmrcsnchz@users.noreply.github.com>
---------
Signed-off-by: JM Sanchez <77505889+jmrcsnchz@users.noreply.github.com>
* feat: drop headers with underscore in their names
* feat: Caddyfile binding and tests for underscore-in-header drop
Add the `allow_underscore_in_headers` global server option, refine the
doc comment, and cover the filter end-to-end: server-level unit tests
(drop, opt-out, debug log, RFC-7230 space rejection), a fastcgi unit
test for the trimmed header name replacer, and forward_auth integration
tests for both the default-drop and opt-out paths.
* remove allow_underscore_in_headers option for now
* fix(encode): prioritize zstd and br over gzip in content negotiation
* test(encode): update unit tests to reflect new default priority ties
* fix(encode): move default preferences to dynamic encode handler and restore generic negotiation helper
* test(encode): call real Provision function in served-response test
* test(encode): rename served-response test to TestServeHTTPDefaultEncodingPreference
* refactor(encode): use slices.SortStableFunc and httptest.NewRecorder as recommended
* refactor(encode): simplify sorting with cmp.Compare and check request error in test
* test(encode): fix variable redeclaration in TestServeHTTPDefaultEncodingPreference
Fix 'no new variables on left side of :=' error by changing 'err :=' to 'err ='
on line 347, since err was already declared on line 332.
This fixes the build failure in the encode module tests.
When the rewrite URI template ends with a literal '?' and contains a placeholder that expands to client-controlled bytes (e.g. {http.request.header.X-Fwd}), those bytes flow into buildQueryString which runs a second Replacer pass. If the bytes contain placeholder syntax such as {env.SECRET}, that placeholder is evaluated, allowing disclosure of environment variables, files (via {file./path}), or internal request vars through the rewritten request URI.
Escape '{' and '}' in the injected query before assigning it to the query variable, so the second pass cannot find any placeholder syntax to evaluate. Operator-written placeholders in the rewrite template are already expanded by the first pass on the path component, so the only '{' or '}' surviving into the injected query must have come from replacement values.
Fixes GHSA-j8px-rmrx-76h9.
Includes three regression tests mirroring the 'is not re-expanded' tests in modules/caddyhttp/vars_test.go.
Co-authored-by: Matt Holt <mholt@users.noreply.github.com>
* tls: add alpn to managed HTTPS records
* tls: centralise HTTPS RR ALPN defaults and registration
Reuse shared protocol defaults instead of repeating the default HTTP protocol list, unify server name registration to carry ALPN in one experimental API and reuse the TLS default ALPN ordering for HTTPS RR publication
* http: centralise effective protocol resolution for HTTPS RR ALPN
Both fallbacks in splitPos relied on golang.org/x/text/search with
search.IgnoreCase, which performs Unicode equivalence matching far beyond
ASCII case folding. Combined with the validated-ASCII guarantee on every
SplitPath entry, that fallback turned non-PHP filenames into PHP scripts:
- when the inner loop hit a non-ASCII byte and the IndexString fallback
returned -1, the loop broke without resetting match=false, so a stale
match=true caused a non-existent .php to be reported (PoC:
"/name.<U+00A1>.txt").
- search.IgnoreCase folded fullwidth, mathematical and circled letters
onto ASCII, so "/shell.<math sans-serif php>",
"/shell.<fullwidth p>hp", "/shell.<circled php>" were all detected as
".php" files.
Replace the fallback with strict byte-level ASCII case-insensitive
matching: any byte >= utf8.RuneSelf in the path can never be part of a
match, since SplitPath entries are validated ASCII-only and lower-cased
in Provision(). This keeps the hot path branch-light and removes the
x/text/search dependency from the main module.
Reported against FrankenPHP as GHSA-3g8v-8r37-cgjm and
GHSA-v4h7-cj44-8fc8. The vulnerable function in this module was adapted
from the same FrankenPHP code.
Saleh
Salynn
futurehua
TowyTowy
techknowlogick
Ta Duc Thien
WeidiDeng
alhuda
Kévin Dunglas
yintaisha
Matthew Holt
wangdongyong
Saleh
Luccin Masirika
long.black
Dionis Ramadani
Bluegate Studio
Sam Ottenhoff
Rhul
Muhammad Syafri, S.Kom
JM Sanchez
Lohit
Vincent Yang
Zen Dodd
Eyüp Can Akman
Brett Bethke
James Hartig
Rayan Salhab
Steffen Busch