GopherProxy

	Clean up request host properly - quark - quark web server
	git clone git://git.suckless.org/quark
	Log
	Files
	Refs
	LICENSE
	---
	commit 3ff82c514becd08922fcf9bc9f4870941650932a
	parent c3ddb2dd14bd7a39dedbbf3520c9a2052dd3e1ff
	Author: Laslo Hunhold <[email protected]>
	Date: Tue, 3 Apr 2018 00:55:52 +0200

	Clean up request host properly

	We all agree that the IPv6 address format is a big clusterfuck and only
	an insane person would've come up with it given the double colons
	interfere with the way one actually appends a port to a normal IPv4 address.

	To counteract in this issue, the RFC specifies that one should enclose
	IPv6-addresses in square brackets to make the disctinction possible,
	i.e.

	host: ::1
	port: 80

	--> [::1]:80

	The host field can contain both a port suffix and, of course by the RFC,
	have the address enclosed in square brackets. Given I personally see
	this as a "transport enclosure" I'd rather like to see it gone as soon
	as possible and thus implement this cleanup in the http-header-parser so
	the output is nice and clean and we don't have to deal with this garbage
	later on.

	Thanks to Josuah Demangeon <[email protected]> for his wonderful input and
	his dedication to read the RFCs 3986 and 2732 in such great detail.

	Diffstat:
	M http.c \| 38 +++++++++++++++++++++++++++++…

	1 file changed, 38 insertions(+), 0 deletions(-)
	---
	diff --git a/http.c b/http.c
	@@ -95,6 +95,7 @@ decode(char src[PATH_MAX], char dest[PATH_MAX])
	int
	http_get_request(int fd, struct request *r)
	{
	+ struct in6_addr res;
	size_t hlen, i, mlen;
	ssize_t off;
	char h[HEADER_MAX], p, q;
	@@ -232,6 +233,43 @@ http_get_request(int fd, struct request *r)
	p = q + (sizeof("\r\n") - 1);
	}

	+ /*
	+ * clean up host
	+ */
	+
	+ p = strrchr(r->field[REQ_HOST], ':');
	+ q = strrchr(r->field[REQ_HOST], ']');
	+
	+ /* strip port suffix but don't interfere with IPv6 bracket notation
	+ * as per RFC 2732 */
	+ if (p && (!q \|\| p > q)) {
	+ /* port suffix must not be empty */
	+ if (*(p + 1) == '\0') {
	+ return http_send_status(fd, S_BAD_REQUEST);
	+ }
	+ *p = '\0';
	+ }
	+
	+ /* strip the brackets from the IPv6 notation and validate the address …
	+ if (q) {
	+ /* brackets must be on the outside */
	+ if (r->field[REQ_HOST][0] != '[' \|\| *(q + 1) != '\0') {
	+ return http_send_status(fd, S_BAD_REQUEST);
	+ }
	+
	+ /* remove the right bracket */
	+ *q = '\0';
	+ p = r->field[REQ_HOST] + 1;
	+
	+ /* validate the contained IPv6 address */
	+ if (inet_pton(AF_INET6, p, &res) != 1) {
	+ return http_send_status(fd, S_BAD_REQUEST);
	+ }
	+
	+ /* copy it into the host field */
	+ memmove(r->field[REQ_HOST], p, q - p + 1);
	+ }
	+
	return 0;
	}