+
+/*
+ * parse_forward
+ * parses a string containing a port forwarding specification of the form:
+ * [listenhost:]listenport:connecthost:connectport
+ * returns number of arguments parsed or zero on error
+ */
+int
+parse_forward(Forward *fwd, const char *fwdspec)
+{
+ int i;
+ char *p, *cp, *fwdarg[4];
+
+ memset(fwd, '\0', sizeof(*fwd));
+
+ cp = p = xstrdup(fwdspec);
+
+ /* skip leading spaces */
+ while (*cp && isspace(*cp))
+ cp++;
+
+ for (i = 0; i < 4; ++i)
+ if ((fwdarg[i] = hpdelim(&cp)) == NULL)
+ break;
+
+ /* Check for trailing garbage in 4-arg case*/
+ if (cp != NULL)
+ i = 0; /* failure */
+
+ switch (i) {
+ case 3:
+ fwd->listen_host = NULL;
+ fwd->listen_port = a2port(fwdarg[0]);
+ fwd->connect_host = xstrdup(cleanhostname(fwdarg[1]));
+ fwd->connect_port = a2port(fwdarg[2]);
+ break;
+
+ case 4:
+ fwd->listen_host = xstrdup(cleanhostname(fwdarg[0]));
+ fwd->listen_port = a2port(fwdarg[1]);
+ fwd->connect_host = xstrdup(cleanhostname(fwdarg[2]));
+ fwd->connect_port = a2port(fwdarg[3]);
+ break;
+ default:
+ i = 0; /* failure */
+ }
+
+ xfree(p);
+
+ if (fwd->listen_port == 0 && fwd->connect_port == 0)
+ goto fail_free;
+
+ if (fwd->connect_host != NULL &&
+ strlen(fwd->connect_host) >= NI_MAXHOST)
+ goto fail_free;
+
+ return (i);
+
+ fail_free:
+ if (fwd->connect_host != NULL)
+ xfree(fwd->connect_host);
+ if (fwd->listen_host != NULL)
+ xfree(fwd->listen_host);
+ return (0);
+}