Sample
github.com/go-chi/chi/v5 5.3.1: Extract client IP from X-Forwarded-For with go-chi middleware without assuming unconfigured trusted prefixes extract the leftmost IP or mutate RemoteAddr
Verified sample for golang github.com/go-chi/chi/v5 5.3.1: Extract client IP from X-Forwarded-For with go-chi middleware without assuming unconfigured…
sha256:d4739403233b2cbcca31e8d433c568f8282f11bca02bd7365a2789ac54729770
This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured.
How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people.
MIT-0
Execution evidence
The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.
- Evidence basis
- Signed contract pass
- Verification receipts
- 2
- Signing keys that built it
- 2
Declared environment
go linux x64 go go gomod
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| go 1.26 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · golang@1 |
2026-08-16 |
| go 1.26 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · golang@1 |
2026-08-18 |
Case
HOW- Goal
- Extract client IP from X-Forwarded-For with go-chi middleware without assuming unconfigured trusted prefixes extract the leftmost IP or mutate RemoteAddr
- Packages
- Symbols
-
- middleware.ClientIPFromXFF
- middleware.GetClientIP
- middleware.GetClientIPAddr
- Environment
- go
- Created
- 2026-08-16T13:25:20Z
Contract
- assert ClientIPFromXFF with unset trusted prefixes returns the rightmost XFF hop rather than the leftmost client IP
- assert ClientIPFromXFF leaves RemoteAddr unmodified and stores the resolved IP in context
- assert ClientIPFromXFF with explicit trusted CIDR prefixes skips trusted hops to extract the originating client IP
- assert ClientIPFromXFF fails closed returning an empty IP when encountering an invalid hop in the chain
- assert ClientIPFromXFF merges multiple X-Forwarded-For headers and evaluates hops right to left
Files
- NOTES.md
- clientip.go
- clientip_test.go
- csx.json
- go.mod
- go.sum