const char *make_relative_path(const char *abs, const char *base)
{
static char buf[PATH_MAX + 1];
- int baselen;
- if (!base)
- return abs;
- baselen = strlen(base);
- if (prefixcmp(abs, base))
+ int i = 0, j = 0;
+
+ if (!base || !base[0])
return abs;
- if (abs[baselen] == '/')
- baselen++;
- else if (base[baselen - 1] != '/')
+ while (base[i]) {
+ if (is_dir_sep(base[i])) {
+ if (!is_dir_sep(abs[j]))
+ return abs;
+ while (is_dir_sep(base[i]))
+ i++;
+ while (is_dir_sep(abs[j]))
+ j++;
+ continue;
+ } else if (abs[j] != base[i]) {
+ return abs;
+ }
+ i++;
+ j++;
+ }
+ if (
+ /* "/foo" is a prefix of "/foo" */
+ abs[j] &&
+ /* "/foo" is not a prefix of "/foobar" */
+ !is_dir_sep(base[i-1]) && !is_dir_sep(abs[j])
+ )
return abs;
- strcpy(buf, abs + baselen);
+ while (is_dir_sep(abs[j]))
+ j++;
+ if (!abs[j])
+ strcpy(buf, ".");
+ else
+ strcpy(buf, abs + j);
return buf;
}
return NULL;
return xstrndup(path, chomp_trailing_dir_sep(path, path_len));
}
+
+int daemon_avoid_alias(const char *p)
+{
+ int sl, ndot;
+
+ /*
+ * This resurrects the belts and suspenders paranoia check by HPA
+ * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
+ * does not do getcwd() based path canonicalizations.
+ *
+ * sl becomes true immediately after seeing '/' and continues to
+ * be true as long as dots continue after that without intervening
+ * non-dot character.
+ */
+ if (!p || (*p != '/' && *p != '~'))
+ return -1;
+ sl = 1; ndot = 0;
+ p++;
+
+ while (1) {
+ char ch = *p++;
+ if (sl) {
+ if (ch == '.')
+ ndot++;
+ else if (ch == '/') {
+ if (ndot < 3)
+ /* reject //, /./ and /../ */
+ return -1;
+ ndot = 0;
+ }
+ else if (ch == 0) {
+ if (0 < ndot && ndot < 3)
+ /* reject /.$ and /..$ */
+ return -1;
+ return 0;
+ }
+ else
+ sl = ndot = 0;
+ }
+ else if (ch == 0)
+ return 0;
+ else if (ch == '/') {
+ sl = 1;
+ ndot = 0;
+ }
+ }
+}