From 5703446c1225212478731b884a215cac77155c59 Mon Sep 17 00:00:00 2001
From: Bryce Kwon <bryce@brycekwon.com>
Date: Sat, 7 Nov 2026 19:29:15 -1000
Subject: Percent-encode a clone url in its href
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An href carried git://example.org/dépôt.git as it was, and the space
of "with space" too, neither of which a url may hold. html_url_path
would also encode the plus of git+ssh, which breaks the scheme, and the
percent of an escape the url was written with, so a whole url gets a
helper that encodes only the bytes RFC 3986 allows nowhere.
---
 source/html.c      | 17 +++++++++++++++++
 source/html.h      |  7 +++++++
 source/ui-shared.c |  4 ++--
 3 files changed, 26 insertions(+), 2 deletions(-)

(limited to 'source')

diff --git a/source/html.c b/source/html.c
index bc7a722..ce9344d 100644
--- a/source/html.c
+++ b/source/html.c
@@ -404,6 +404,23 @@ void cgit_add_url_path(struct strbuf *sb, const char *txt)
 	}
 }
 
+void html_attr_url(const char *txt)
+{
+	struct strbuf url = STRBUF_INIT;
+
+	// These are the bytes RFC 3986 allows in no part of a url.
+	for (; *txt; txt++) {
+		unsigned char c = *txt;
+
+		if (c <= ' ' || c >= 0x7f || strchr("\"<>\\^`{|}", c))
+			strbuf_addstr(&url, url_escape_table[c]);
+		else
+			strbuf_addch(&url, c);
+	}
+	html_attr(url.buf);
+	strbuf_release(&url);
+}
+
 void html_url_arg(const char *txt)
 {
 	const char *p = txt;
diff --git a/source/html.h b/source/html.h
index d3cd8fe..4c16f85 100644
--- a/source/html.h
+++ b/source/html.h
@@ -84,6 +84,13 @@ extern void html_url_path(const char *txt);
  */
 extern void cgit_add_url_path(struct strbuf *sb, const char *txt);
 
+/*
+ * Escape a whole url given in the configuration, such as a clone url, for an
+ * attribute value. Only a byte no url may carry is percent-encoded, so the
+ * scheme, the delimiters and any escape the url was written with are kept.
+ */
+extern void html_attr_url(const char *txt);
+
 extern void html_url_arg(const char *txt);
 extern void html_header_arg_in_quotes(const char *txt);
 extern void html_header_query(const char *txt);
diff --git a/source/ui-shared.c b/source/ui-shared.c
index 985f33d..9e3757d 100644
--- a/source/ui-shared.c
+++ b/source/ui-shared.c
@@ -243,7 +243,7 @@ static void print_rel_vcs_link(const char *url)
 	if (!has_uri_scheme(url))
 		return;
 	html("<link rel='vcs-git' href='");
-	html_attr(url);
+	html_attr_url(url);
 	html("' title='");
 	html_attr(ctx.repo->name);
 	html(" Git repository'>\n");
@@ -1736,7 +1736,7 @@ void cgit_print_clone_row(const char *url, int colspan)
 	html("<a rel='vcs-git' title='");
 	html_attr(ctx.repo->name);
 	html(" Git repository' href='");
-	html_attr(href);
+	html_attr_url(href);
 	html("'>");
 	html_txt(url);
 	html("</a></td></tr>\n");
-- 
cgit 2.12.1