File quit-timer.patch of Package netcat-openbsd
From: Aron Xu <aron@debian.org>
Date: Mon, 13 Feb 2012 15:16:04 +0800
Subject: New flag '-q' to specify a quit timer
---
nc.1 | 10 ++++++++++
netcat.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++++-----------
2 files changed, 58 insertions(+), 11 deletions(-)
diff --git a/nc.1 b/nc.1
index 478fedd..fbcc098 100644
--- a/nc.1
+++ b/nc.1
@@ -41,6 +41,7 @@
.Op Fl O Ar length
.Op Fl P Ar proxy_username
.Op Fl p Ar source_port
+.Op Fl q Ar seconds
.Op Fl s Ar sourceaddr
.Op Fl T Ar keyword
.Op Fl V Ar rtable
@@ -167,6 +168,15 @@ Proxy authentication is only supported for HTTP CONNECT proxies at present.
Specify the source port
.Nm
should use, subject to privilege restrictions and availability.
+.It Fl q Ar seconds
+after EOF on stdin, wait the specified number of
+.Ar seconds
+and then quit. If
+.Ar seconds
+is negative, wait forever (default). Specifying a non-negative
+.Ar seconds
+implies
+.Fl N .
.It Fl r
Choose source and/or destination ports randomly
instead of sequentially within a range or in the order that the system
diff --git a/netcat.c b/netcat.c
index 2f3e9a8..03d339c 100644
--- a/netcat.c
+++ b/netcat.c
@@ -139,6 +139,7 @@ int Nflag; /* shutdown() network socket */
int nflag; /* Don't do name look up */
char *Pflag; /* Proxy username */
char *pflag; /* Localport flag */
+int qflag = -1; /* Quit after some secs */
int rflag; /* Random ports flag */
char *sflag; /* Source Address */
int tflag; /* Telnet Emulation */
@@ -223,6 +224,7 @@ ssize_t fillbuf(int, unsigned char *, size_t *);
#endif
static int connect_with_timeout(int, const struct sockaddr *, socklen_t, int);
+static void quit(int sig);
int
main(int argc, char *argv[])
@@ -255,9 +257,9 @@ main(int argc, char *argv[])
while ((ch = getopt(argc, argv,
#ifdef HAVE_TLS
- "46C:cDde:FH:hI:i:K:klM:m:NnO:o:P:p:R:rSs:T:tUuV:vW:w:X:x:Z:z"))
+ "46C:cDde:FH:hI:i:K:klM:m:NnO:o:P:p:q:R:rSs:T:tUuV:vW:w:X:x:Z:z"))
#else
- "46CDdFhI:i:klM:m:NnO:P:p:rSs:T:tUuV:vW:w:X:x:z"))
+ "46CDdFhI:i:klM:m:NnO:P:p:q:rSs:T:tUuV:vW:w:X:x:z"))
#endif
!= -1) {
switch (ch) {
@@ -349,6 +351,13 @@ main(int argc, char *argv[])
case 'p':
pflag = optarg;
break;
+ case 'q':
+ qflag = strtonum(optarg, INT_MIN, INT_MAX, &errstr);
+ if (errstr)
+ errx(1, "quit timer %s: %s", errstr, optarg);
+ if (qflag >= 0)
+ Nflag = 1;
+ break;
#ifdef HAVE_TLS
case 'R':
tls_cachanged = 1;
@@ -1335,15 +1344,27 @@ readwrite(int net_fd)
while (1) {
/* both inputs are gone, buffers are empty, we are done */
if (pfd[POLL_STDIN].fd == -1 && pfd[POLL_NETIN].fd == -1 &&
- stdinbufpos == 0 && netinbufpos == 0)
- return;
+ stdinbufpos == 0 && netinbufpos == 0) {
+ if (qflag <= 0)
+ return;
+ goto delay_exit;
+ }
/* both outputs are gone, we can't continue */
- if (pfd[POLL_NETOUT].fd == -1 && pfd[POLL_STDOUT].fd == -1)
- return;
+ if (pfd[POLL_NETOUT].fd == -1 && pfd[POLL_STDOUT].fd == -1) {
+ if (qflag <= 0)
+ return;
+ goto delay_exit;
+ }
/* listen and net in gone, queues empty, done */
if (lflag && pfd[POLL_NETIN].fd == -1 &&
- stdinbufpos == 0 && netinbufpos == 0)
- return;
+ stdinbufpos == 0 && netinbufpos == 0) {
+ if (qflag <= 0)
+ return;
+delay_exit:
+ close(net_fd);
+ signal(SIGALRM, quit);
+ alarm(qflag);
+ }
/* poll */
num_fds = poll(pfd, 4, timeout);
@@ -1500,6 +1521,13 @@ readwrite(int net_fd)
if (pfd[POLL_NETOUT].fd != -1 && Nflag)
shutdown(pfd[POLL_NETOUT].fd, SHUT_WR);
pfd[POLL_NETOUT].fd = -1;
+ /* #817050: handle UDP sockets and kflag */
+ if ((lflag || uflag) && pfd[POLL_NETIN].fd != -1 &&
+ qflag >= 0 && netinbufpos == 0) {
+ shutdown(pfd[POLL_NETIN].fd, SHUT_RD);
+ pfd[POLL_NETIN].fd = -1;
+ kflag = 0;
+ }
}
/* net in gone and queue empty? */
if (pfd[POLL_NETIN].fd == -1 && netinbufpos == 0) {
@@ -2106,6 +2134,7 @@ help(void)
\t-O length TCP send buffer length\n\
\t-P proxyuser\tUsername for proxy authentication\n\
\t-p port\t Specify local port for remote connects\n\
+ \t-q secs\t quit after EOF on stdin and delay of secs\n\
\t-r Randomize remote ports\n\
\t-S Enable the TCP MD5 signature option\n\
\t-s sourceaddr Local source address\n\
@@ -2130,10 +2159,18 @@ usage(int ret)
fprintf(stderr,
"usage: nc [-46CDdFhklNnrStUuvz] [-I length] [-i interval] [-M ttl]\n"
"\t [-m minttl] [-O length] [-P proxy_username] [-p source_port]\n"
- "\t [-s sourceaddr] [-T keyword] [-V rtable] [-W recvlimit] "
- "[-w timeout]\n"
- "\t [-X proxy_protocol] [-x proxy_address[:port]]\n"
+ "\t [-q seconds] [-s sourceaddr] [-T keyword] [-V rtable] [-W recvlimit]\n"
+ "\t [-w timeout] [-X proxy_protocol] [-x proxy_address[:port]]\n"
"\t [destination] [port]\n");
if (ret)
exit(1);
}
+
+/*
+ * quit()
+ * handler for a "-q" timeout (exit 0 instead of 1)
+ */
+static void quit(__attribute__((unused)) int sig)
+{
+ exit(0);
+}
