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netcat-openbsd/send-crlf.patch

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From: Aron Xu <aron@debian.org>
Date: Mon, 13 Feb 2012 14:57:45 +0800
Subject: New flag '-C' to translate terminal line feeds to CRLF
---
nc.1 | 9 ++++++--
netcat.c | 72 +++++++++++++++++++++++++++++++++++-----------------------------
2 files changed, 47 insertions(+), 34 deletions(-)
diff --git a/nc.1 b/nc.1
index 2eb732e..478fedd 100644
--- a/nc.1
+++ b/nc.1
@@ -33,7 +33,7 @@
.Nd arbitrary TCP and UDP connections and listens
.Sh SYNOPSIS
.Nm nc
-.Op Fl 46DdFhklNnrStUuvz
+.Op Fl 46CDdFhklNnrStUuvz
.Op Fl I Ar length
.Op Fl i Ar interval
.Op Fl M Ar ttl
@@ -92,6 +92,11 @@ The options are as follows:
Use IPv4 addresses only.
.It Fl 6
Use IPv6 addresses only.
+.It Fl C
+Send CRLF as line-ending. Each line feed (LF) character from the input
+data is translated into CR+LF before being written to the socket. Line
+feed characters that are already preceded with a carriage return (CR)
+are not translated. Received data is not affected.
.It Fl D
Enable debugging on the socket.
.It Fl d
@@ -380,7 +385,7 @@ More complicated examples can be built up when the user knows the format
of requests required by the server.
As another example, an email may be submitted to an SMTP server using:
.Bd -literal -offset indent
-$ nc localhost 25 << EOF
+$ nc [\-C] localhost 25 << EOF
HELO host.example.com
MAIL FROM:<user@host.example.com>
RCPT TO:<user2@host.example.com>
diff --git a/netcat.c b/netcat.c
index 2dc1abd..2f3e9a8 100644
--- a/netcat.c
+++ b/netcat.c
@@ -166,6 +166,8 @@ char *tls_expecthash; /* required hash of peer cert */
char *tls_ciphers; /* TLS ciphers */
char *tls_protocols; /* TLS protocols */
FILE *Zflag; /* file to save peer cert */
+#else
+int Cflag = 0; /* CRLF line-ending */
#endif
int recvcount, recvlimit;
@@ -216,7 +218,7 @@ ssize_t fillbuf(int, unsigned char *, size_t *, struct tls *);
void tls_setup_client(struct tls *, int, char *);
struct tls *tls_setup_server(struct tls *, int, char *);
#else
-ssize_t drainbuf(int, unsigned char *, size_t *);
+ssize_t drainbuf(int, unsigned char *, size_t *, int);
ssize_t fillbuf(int, unsigned char *, size_t *);
#endif
@@ -255,7 +257,7 @@ main(int argc, char *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"))
#else
- "46DdFhI:i:klM:m:NnO:P:p:rSs:T:tUuV:vW:w:X:x:z"))
+ "46CDdFhI:i:klM:m:NnO:P:p:rSs:T:tUuV:vW:w:X:x:z"))
#endif
!= -1) {
switch (ch) {
@@ -285,6 +287,10 @@ main(int argc, char *argv[])
case 'c':
usetls = 1;
break;
+#else
+ case 'C':
+ Cflag = 1;
+ break;
#endif
case 'd':
dflag = 1;
@@ -1339,12 +1345,6 @@ readwrite(int net_fd)
stdinbufpos == 0 && netinbufpos == 0)
return;
- /* help says -i is for "wait between lines sent". We read and
- * write arbitrary amounts of data, and we don't want to start
- * scanning for newlines, so this is as good as it gets */
- if (iflag)
- sleep(iflag);
-
/* poll */
num_fds = poll(pfd, 4, timeout);
@@ -1424,7 +1424,7 @@ readwrite(int net_fd)
pfd[POLL_NETOUT].events = POLLOUT;
else
#else
- &stdinbufpos);
+ &stdinbufpos, (iflag || Cflag) ? 1 : 0);
#endif
if (ret == -1)
pfd[POLL_NETOUT].fd = -1;
@@ -1483,7 +1483,7 @@ readwrite(int net_fd)
pfd[POLL_STDOUT].events = POLLOUT;
else
#else
- &netinbufpos);
+ &netinbufpos, 0);
#endif
if (ret == -1)
pfd[POLL_STDOUT].fd = -1;
@@ -1509,36 +1509,43 @@ readwrite(int net_fd)
}
ssize_t
-#ifdef HAVE_TLS
-drainbuf(int fd, unsigned char *buf, size_t *bufpos, struct tls *tls)
-#else
-drainbuf(int fd, unsigned char *buf, size_t *bufpos)
-#endif
+drainbuf(int fd, unsigned char *buf, size_t *bufpos, int oneline)
{
- ssize_t n;
+ ssize_t n, r;
ssize_t adjust;
+ unsigned char *lf = NULL;
if (fd == -1)
return -1;
-#ifdef HAVE_TLS
- if (tls) {
- n = tls_write(tls, buf, *bufpos);
- if (n == -1)
- errx(1, "tls write failed (%s)", tls_error(tls));
- } else {
-#endif
- n = write(fd, buf, *bufpos);
- /* don't treat EAGAIN, EINTR as error */
- if (n == -1 && (errno == EAGAIN || errno == EINTR))
-#ifdef HAVE_TLS
- n = TLS_WANT_POLLOUT;
+ if (oneline)
+ lf = memchr(buf, '\n', *bufpos);
+ if (lf == NULL) {
+ n = *bufpos;
+ oneline = 0;
}
-#else
- n = -2;
-#endif
+ else if (Cflag && (lf == buf || buf[lf - buf - 1] != '\r')) {
+ n = lf - buf;
+ oneline = 2;
+ }
+ else
+ n = lf - buf + 1;
+ if (n > 0)
+ n = write(fd, buf, n);
+
+ /* don't treat EAGAIN, EINTR as error */
+ if (n == -1 && (errno == EAGAIN || errno == EINTR))
+ n = -2;
+ if (oneline == 2 && n >= 0)
+ n++;
if (n <= 0)
return n;
+
+ if (oneline == 2 && (r = atomicio(vwrite, fd, "\r\n", 2)) != 2)
+ err(1, "write failed (%zu/2)", r);
+ if (oneline > 0 && iflag)
+ sleep(iflag);
+
/* adjust buffer */
adjust = *bufpos - n;
if (adjust > 0)
@@ -2083,6 +2090,7 @@ help(void)
fprintf(stderr, "\tCommand Summary:\n\
\t-4 Use IPv4\n\
\t-6 Use IPv6\n\
+ \t-C Send CRLF as line-ending\n\
\t-D Enable the debug socket option\n\
\t-d Detach from stdin\n\
\t-F Pass socket fd\n\
@@ -2120,7 +2128,7 @@ void
usage(int ret)
{
fprintf(stderr,
- "usage: nc [-46DdFhklNnrStUuvz] [-I length] [-i interval] [-M ttl]\n"
+ "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"
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