id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
2184	ngx_http_parse_header_line	https://stackoverflow.com/users/279251/klaus-triendl		"nginx treats dots ""."" as invalid characters in HTTP header field names, which it shouldn't according to RFC 7230.

RFC 7230 defines a header field name to be a 'token' as follows:
{{{
field-name = token
token = 1*tchar
tchar = ""!"" / ""#"" / ""$"" / ""%"" / ""&"" / ""'"" / ""*""
        / ""+"" / ""-"" / ""."" / ""^"" / ""_"" / ""`"" / ""|"" / ""~""
        / DIGIT / ALPHA
        ; any VCHAR, except delimiters
}}}
(see [https://www.ietf.org/rfc/rfc7230.html#section-3.2 section Header Fields] and [https://www.ietf.org/rfc/rfc7230.html#section-3.2.6 section Field Value Components])

however, `ngx_http_parse_header_line()` only accepts the underscore ""_"" outside of alpha-numeric characters and the dash.


My use case are custom client HTTP headers in ""reverse domain notation"".
"	defect	closed	minor		nginx-core	1.19.x	duplicate		https://stackoverflow.com/users/279251/klaus-triendl		"nginx version: nginx/1.19.10
built by cl 16.00.40219.01 for 80x86
built with OpenSSL 1.1.1k  25 Mar 2021
TLS SNI support enabled
configure arguments: --with-cc=cl --builddir=objs.msvc8 --with-debug --prefix= --conf-path=conf/nginx.conf --pid-path=logs/nginx.pid --http-log-path=logs/access.log --error-log-path=logs/error.log --sbin-path=nginx.exe --http-client-body-temp-path=temp/client_body_temp --http-proxy-temp-path=temp/proxy_temp --http-fastcgi-temp-path=temp/fastcgi_temp --http-scgi-temp-path=temp/scgi_temp --http-uwsgi-temp-path=temp/uwsgi_temp --with-cc-opt=-DFD_SETSIZE=1024 --with-pcre=objs.msvc8/lib/pcre-8.44 --with-zlib=objs.msvc8/lib/zlib-1.2.11 --with-http_v2_module --with-http_realip_module --with-http_addition_module --with-http_sub_module --with-http_dav_module --with-http_stub_status_module --with-http_flv_module --with-http_mp4_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_auth_request_module --with-http_random_index_module --with-http_secure_link_module --with-http_slice_module --with-mail --with-stream --with-openssl=objs.msvc8/lib/openssl-1.1.1k --with-openssl-opt='no-asm no-tests -D_WIN32_WINNT=0x0501' --with-http_ssl_module --with-mail_ssl_module --with-stream_ssl_module"