Function sanitize_client

daemon.c:560–572

* Sanitize a string from the client so that it's OK to be inserted into a * filesystem path. Specifically, we disallow directory separators, runs * of "..", and trailing and leading dots, which means that the client * cannot escape our base path via ".." traversal. */

 * cannot escape our base path via ".." traversal.
 */
static void sanitize_client(struct strbuf *out, const char *in)
{
	for (; *in; in++) {
		if (is_dir_sep(*in))
			continue;
		if (*in == '.' && (!out->len || out->buf[out->len - 1] == '.'))
			continue;
		strbuf_addch(out, *in);
	}

	while (out->len && out->buf[out->len - 1] == '.')
		strbuf_setlen(out, out->len - 1);
}

/*
 * Like sanitize_client, but we also perform any canonicalization