[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/busybox/src/networking/pscan.c b/ap/app/busybox/src/networking/pscan.c
new file mode 100644
index 0000000..28005ad
--- /dev/null
+++ b/ap/app/busybox/src/networking/pscan.c
@@ -0,0 +1,165 @@
+/*
+ * Pscan is a mini port scanner implementation for busybox
+ *
+ * Copyright 2007 Tito Ragusa <farmatito@tiscali.it>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+//usage:#define pscan_trivial_usage
+//usage:       "[-cb] [-p MIN_PORT] [-P MAX_PORT] [-t TIMEOUT] [-T MIN_RTT] HOST"
+//usage:#define pscan_full_usage "\n\n"
+//usage:       "Scan a host, print all open ports\n"
+//usage:     "\n	-c	Show closed ports too"
+//usage:     "\n	-b	Show blocked ports too"
+//usage:     "\n	-p	Scan from this port (default 1)"
+//usage:     "\n	-P	Scan up to this port (default 1024)"
+//usage:     "\n	-t	Timeout (default 5000 ms)"
+//usage:     "\n	-T	Minimum rtt (default 5 ms, increase for congested hosts)"
+
+#include "libbb.h"
+
+/* debugging */
+#ifdef DEBUG_PSCAN
+#define DMSG(...) bb_error_msg(__VA_ARGS__)
+#define DERR(...) bb_perror_msg(__VA_ARGS__)
+#else
+#define DMSG(...) ((void)0)
+#define DERR(...) ((void)0)
+#endif
+
+static const char *port_name(unsigned port)
+{
+	struct servent *server;
+
+	server = getservbyport(htons(port), NULL);
+	if (server)
+		return server->s_name;
+	return "unknown";
+}
+
+/* We don't expect to see 1000+ seconds delay, unsigned is enough */
+#define MONOTONIC_US() ((unsigned)monotonic_us())
+
+int pscan_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int pscan_main(int argc UNUSED_PARAM, char **argv)
+{
+	const char *opt_max_port = "1024";      /* -P: default max port */
+	const char *opt_min_port = "1";         /* -p: default min port */
+	const char *opt_timeout = "5000";       /* -t: default timeout in msec */
+	/* We estimate rtt and wait rtt*4 before concluding that port is
+	 * totally blocked. min rtt of 5 ms may be too low if you are
+	 * scanning an Internet host behind saturated/traffic shaped link.
+	 * Rule of thumb: with min_rtt of N msec, scanning 1000 ports
+	 * will take N seconds at absolute minimum */
+	const char *opt_min_rtt = "5";          /* -T: default min rtt in msec */
+	const char *result_str;
+	len_and_sockaddr *lsap;
+	int s;
+	unsigned opt;
+	unsigned port, max_port, nports;
+	unsigned closed_ports = 0;
+	unsigned open_ports = 0;
+	/* all in usec */
+	unsigned timeout;
+	unsigned min_rtt;
+	unsigned rtt_4;
+	unsigned start, diff;
+
+	opt_complementary = "=1"; /* exactly one non-option */
+	opt = getopt32(argv, "cbp:P:t:T:", &opt_min_port, &opt_max_port, &opt_timeout, &opt_min_rtt);
+	argv += optind;
+	max_port = xatou_range(opt_max_port, 1, 65535);
+	port = xatou_range(opt_min_port, 1, max_port);
+	nports = max_port - port + 1;
+	min_rtt = xatou_range(opt_min_rtt, 1, INT_MAX/1000 / 4) * 1000;
+	timeout = xatou_range(opt_timeout, 1, INT_MAX/1000 / 4) * 1000;
+	/* Initial rtt is BIG: */
+	rtt_4 = timeout;
+
+	DMSG("min_rtt %u timeout %u", min_rtt, timeout);
+
+	lsap = xhost2sockaddr(*argv, port);
+	printf("Scanning %s ports %u to %u\n Port\tProto\tState\tService\n",
+			*argv, port, max_port);
+
+	for (; port <= max_port; port++) {
+		DMSG("rtt %u", rtt_4);
+
+		/* The SOCK_STREAM socket type is implemented on the TCP/IP protocol. */
+		set_nport(&lsap->u.sa, htons(port));
+		s = xsocket(lsap->u.sa.sa_family, SOCK_STREAM, 0);
+		/* We need unblocking socket so we don't need to wait for ETIMEOUT. */
+		/* Nonblocking connect typically "fails" with errno == EINPROGRESS */
+		ndelay_on(s);
+
+		DMSG("connect to port %u", port);
+		result_str = NULL;
+		start = MONOTONIC_US();
+		if (connect(s, &lsap->u.sa, lsap->len) == 0) {
+			/* Unlikely, for me even localhost fails :) */
+			DMSG("connect succeeded");
+			goto open;
+		}
+		/* Check for untypical errors... */
+		if (errno != EAGAIN && errno != EINPROGRESS
+		 && errno != ECONNREFUSED
+		) {
+			bb_perror_nomsg_and_die();
+		}
+
+		diff = 0;
+		while (1) {
+			if (errno == ECONNREFUSED) {
+				if (opt & 1) /* -c: show closed too */
+					result_str = "closed";
+				closed_ports++;
+				break;
+			}
+			DERR("port %u errno %d @%u", port, errno, diff);
+
+			if (diff > rtt_4) {
+				if (opt & 2) /* -b: show blocked too */
+					result_str = "blocked";
+				break;
+			}
+			/* Can sleep (much) longer than specified delay.
+			 * We check rtt BEFORE we usleep, otherwise
+			 * on localhost we'll have no writes done (!)
+			 * before we exceed (rather small) rtt */
+			usleep(rtt_4/8);
+ open:
+			diff = MONOTONIC_US() - start;
+			DMSG("write to port %u @%u", port, diff - start);
+			if (write(s, " ", 1) >= 0) { /* We were able to write to the socket */
+				open_ports++;
+				result_str = "open";
+				break;
+			}
+		}
+		DMSG("out of loop @%u", diff);
+		if (result_str)
+			printf("%5u" "\t" "tcp" "\t" "%s" "\t" "%s" "\n",
+					port, result_str, port_name(port));
+
+		/* Estimate new rtt - we don't want to wait entire timeout
+		 * for each port. *4 allows for rise in net delay.
+		 * We increase rtt quickly (rtt_4*4), decrease slowly
+		 * (diff is at least rtt_4/8, *4 == rtt_4/2)
+		 * because we don't want to accidentally miss ports. */
+		rtt_4 = diff * 4;
+		if (rtt_4 < min_rtt)
+			rtt_4 = min_rtt;
+		if (rtt_4 > timeout)
+			rtt_4 = timeout;
+		/* Clean up */
+		close(s);
+	}
+	if (ENABLE_FEATURE_CLEAN_UP) free(lsap);
+
+	printf("%d closed, %d open, %d timed out (or blocked) ports\n",
+					closed_ports,
+					open_ports,
+					nports - (closed_ports + open_ports));
+	return EXIT_SUCCESS;
+}