Fix cookie name escaping and stored hash trimming

1 file changed, 10 insertions, 1 deletion

diff --git a/custom/extensions/auth-inline.lua b/custom/extensions/auth-inline.lua
index 168a444..0cd9da9 100644
--- a/custom/extensions/auth-inline.lua
+++ b/custom/extensions/auth-inline.lua
@@ -206,13 +206,22 @@ function parse_qs(qs)
 	return tab
 end
 
+-- Escape the Lua pattern magic characters, so a name is matched literally.
+local function pattern_escape(s)
+	return (string.gsub(s, "([%^%$%(%)%%%.%[%]%*%+%-%?])", "%%%1"))
+end
+
 -- Return the value of the named cookie, or nil. The stored token was already
 -- url-encoded by secure_value, so it is returned verbatim, which keeps the
 -- write path (set_cookie) and the read path symmetric. Decoding it here would
 -- break the signature check for any value carrying a percent escape.
+--
+-- The name is escaped because it lands in a pattern. A cookie_name holding a
+-- magic character, say "cgit-auth", would otherwise read as a pattern and stop
+-- matching its own cookie while matching names nobody configured.
 function get_cookie(cookies, name)
 	cookies = string.gsub(";" .. (cookies or "") .. ";", "%s*;%s*", ";")
-	return string.match(cookies, ";" .. name .. "=(.-);")
+	return string.match(cookies, ";" .. pattern_escape(name) .. "=(.-);")
 end
 
 function tohex(b)