fix: generate proper Sec-WebSocket-Key for WebSocket handshake#1228
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Tonkpils wants to merge 1 commit intogo-rod:mainfrom
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fix: generate proper Sec-WebSocket-Key for WebSocket handshake#1228Tonkpils wants to merge 1 commit intogo-rod:mainfrom
Tonkpils wants to merge 1 commit intogo-rod:mainfrom
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The handshake method set Sec-WebSocket-Key to the literal string "nil", which causes 400 Bad Request on servers that validate the key per RFC 6455 (e.g. Browserless.io). - Generate a random 16-byte base64-encoded key instead of "nil" - Fix header override comparison to use case-insensitive match (Go canonicalizes to Sec-Websocket-Key, breaking exact match) - Add test verifying the key is valid base64, not "nil"
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| defaultSecKey := "nil" | ||
| keyBytes := make([]byte, 16) | ||
| _, _ = rand.Read(keyBytes) | ||
| defaultSecKey := base64.StdEncoding.EncodeToString(keyBytes) |
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You could set directly secKey here instead of using 2 different vars.
krichprollsch
approved these changes
Mar 30, 2026
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The
handshakemethod setsSec-WebSocket-Keyto the literal string"nil", which causes400 Bad Requeston WebSocket servers that validate the key per RFC 6455 §4.1 — notably Browserless.io. #1092 (comment)What changed
"nil"k == "Sec-WebSocket-Key"check uses exact case, but Go'shttp.Headercanonicalizes keys (lowercasewinWebsocket). Switched tostrings.EqualFoldso user-provided header overrides actually work.TestSecWebSocketKeyIsValidverifies the generated key is valid base64 (16 bytes decoded) and not"nil", and that consecutive keys are unique.Context
Ran into this connecting to Browserless.io from a Go service using Rod. The literal
"nil"key doesn't pass their handshake validation. Generating a real key per the RFC spec fixes it.