HTTP header validation error: trailing whitespace in platform.version() causes Connection error

[asamawi]

Bug Report: HTTP Header Validation Error Due to Trailing Whitespace in platform.version()

Environment

• kimi-cli version: 1.15.0
• Python version: 3.13.12
• OS: Ubuntu 22.04.5 LTS (Jammy)
• Kernel: 6.8.0-101-generic

Problem Description

The CLI fails with a Connection error on certain Linux systems because platform.version() returns a string with a trailing space, which violates HTTP header validation in the h11 library.

Error Message

httpcore.LocalProtocolError: Illegal header value b'#101~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Wed Feb 11 13:19:54 UTC '

Root Cause

In kimi_cli/auth/oauth.py, the _ascii_header_value() function does not strip whitespace from header values:

def _ascii_header_value(value: str, *, fallback: str = "unknown") -> str:
    try:
        value.encode("ascii")
        return value  # <-- Missing .strip() here
    except UnicodeEncodeError:
        sanitized = value.encode("ascii", errors="ignore").decode("ascii").strip()
        return sanitized or fallback

On some Linux systems, platform.version() returns:

'#101~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Wed Feb 11 13:19:54 UTC '
#                                                                    ^
#                                                            trailing space!

This value is used in X-Msh-Os-Version header via _common_headers():

"X-Msh-Os-Version": platform.version(),

The h11 library (used by httpx/httpcore) validates headers against RFC 7230 and rejects values with trailing whitespace.

Steps to Reproduce

1. Install kimi-cli on Ubuntu 22.04 with kernel 6.8.0-101-generic
2. Run kimi login to authenticate
3. Run any command that makes an API call:

   echo "hi" | kimi --print --quiet

4. Observe Connection error

Workaround / Fix

Add .strip() to the return value in _ascii_header_value():

def _ascii_header_value(value: str, *, fallback: str = "unknown") -> str:
    try:
        value.encode("ascii")
        return value.strip()  # Fixed: strip whitespace
    except UnicodeEncodeError:
        sanitized = value.encode("ascii", errors="ignore").decode("ascii").strip()
        return sanitized or fallback

Verification

After applying the fix locally:

$ echo "hi" | kimi --print --quiet
Hey there! 👋

I'm Kimi, ready to help you with whatever you need. What's on your mind today?

Additional Context

• This issue is specific to certain kernel builds where uname -v includes trailing whitespace
• The bug affects the X-Msh-Os-Version header and potentially other headers if they contain user/system data with whitespace
• Related: h11's strict validation of field-value pattern in RFC 7230

[zj6882917]

是的，我也遇到了同样的问题，就是这样修复的

---

Yes, I also encountered the same problem, this is how I fixed it

[Br1an67]

This issue has been resolved by #1401 (fix(oauth): strip whitespace from HTTP header values on Linux), which sanitizes all HTTP header values via _ascii_header_value() — stripping trailing whitespace and filtering non-ASCII characters before sending. The fix is available in kimi-cli v1.18.0+. This issue can be closed.