From e4c497a1944f035b3e4e947d9518d947d42d40a1 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Tue, 12 Oct 2021 17:12:26 -0400 Subject: [PATCH] urlmatch: add underscore to URL_HOST_CHARS When parsing a URL to normalize it, we allow hostnames to contain only dot (".") or dash ("-"), plus brackets and colons for IPv6 literals. This matches the old URL standard in RFC 1738, which says: host = hostname | hostnumber hostname = *[ domainlabel "." ] toplabel domainlabel = alphadigit | alphadigit *[ alphadigit | "-" ] alphadigit But this was later updated by RFC 3986, which is more liberal: host = IP-literal / IPv4address / reg-name reg-name = *( unreserved / pct-encoded / sub-delims ) unreserved = ALPHA / DIGIT / "-" / "." / "_" / "~" While names with underscore in them are not common and possibly violate some DNS rules, they do work in practice, and we will happily contact them over http://, git://, or ssh://. It seems odd to ignore them for purposes of URL matching, especially when the URL RFC seems to allow them. There shouldn't be any downside here. It's not a syntactically significant character in a URL, so we won't be confused about parsing; we'd have simply rejected such a URL previously (the test here checks the url code directly, but the obvious user-visible effect would be failing to match credential.http://foo_bar.example.com.helper, or similar config in http..*). Arguably we'd want to allow tilde ("~") here, too. There's likewise probably no downside, but I didn't add it simply because it seems like an even less likely character to appear in a hostname. Reported-by: Alex Waite Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- t/t0110-urlmatch-normalization.sh | 2 +- urlmatch.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/t/t0110-urlmatch-normalization.sh b/t/t0110-urlmatch-normalization.sh index f99529d838..4dc9fecf72 100755 --- a/t/t0110-urlmatch-normalization.sh +++ b/t/t0110-urlmatch-normalization.sh @@ -47,7 +47,7 @@ test_expect_success 'url authority' ' test-tool urlmatch-normalization "scheme://@host" && test-tool urlmatch-normalization "scheme://%00@host" && ! test-tool urlmatch-normalization "scheme://%%@host" && - ! test-tool urlmatch-normalization "scheme://host_" && + test-tool urlmatch-normalization "scheme://host_" && test-tool urlmatch-normalization "scheme://user:pass@host/" && test-tool urlmatch-normalization "scheme://@host/" && test-tool urlmatch-normalization "scheme://host/" && diff --git a/urlmatch.c b/urlmatch.c index 33a2ccd306..03ad3f30a9 100644 --- a/urlmatch.c +++ b/urlmatch.c @@ -5,7 +5,7 @@ #define URL_DIGIT "0123456789" #define URL_ALPHADIGIT URL_ALPHA URL_DIGIT #define URL_SCHEME_CHARS URL_ALPHADIGIT "+.-" -#define URL_HOST_CHARS URL_ALPHADIGIT ".-[:]" /* IPv6 literals need [:] */ +#define URL_HOST_CHARS URL_ALPHADIGIT ".-_[:]" /* IPv6 literals need [:] */ #define URL_UNSAFE_CHARS " <>\"%{}|\\^`" /* plus 0x00-0x1F,0x7F-0xFF */ #define URL_GEN_RESERVED ":/?#[]@" #define URL_SUB_RESERVED "!$&'()*+,;="