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| | From: Aron Xu <aron@debian.org>
Date: Mon, 13 Feb 2012 14:57:45 +0800
Subject: send crlf
---
nc.1 | 9 +++++--
netcat.c | 74 ++++++++++++++++++++++++++++++++++-----------------------------
2 files changed, 48 insertions(+), 35 deletions(-)
--- 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
@@ -377,7 +382,7 @@ More complicated examples can be built u
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 \*(Lt\*(Lt EOF
+$ nc [\-C] localhost 25 \*(Lt\*(Lt EOF
HELO host.example.com
MAIL FROM:\*(Ltuser@host.example.com\*(Gt
RCPT TO:\*(Ltuser2@host.example.com\*(Gt
--- a/netcat.c
+++ b/netcat.c
@@ -166,6 +166,8 @@ char *tls_expecthash; /* required hash
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;
@@ -215,7 +217,7 @@ ssize_t fillbuf(int, unsigned char *, si
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
@@ -256,7 +258,7 @@ main(int argc, char *argv[])
# if defined(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) {
@@ -286,6 +288,10 @@ main(int argc, char *argv[])
case 'c':
usetls = 1;
break;
+# else
+ case 'C':
+ Cflag = 1;
+ break;
# endif
case 'd':
dflag = 1;
@@ -1323,12 +1329,6 @@ 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);
@@ -1408,7 +1408,7 @@ 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;
@@ -1467,7 +1467,7 @@ readwrite(int net_fd)
pfd[POLL_STDOUT].events = POLLOUT;
else
# else
- &netinbufpos);
+ &netinbufpos, 0);
# endif
if (ret == -1)
pfd[POLL_STDOUT].fd = -1;
@@ -1493,33 +1493,40 @@ readwrite(int net_fd)
}
ssize_t
-# if defined(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 defined(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))
-# if defined(TLS)
- n = TLS_WANT_POLLOUT;
- }
-# else
- n = -2;
-# endif
+ if (oneline)
+ lf = memchr(buf, '\n', *bufpos);
+ if (lf == NULL) {
+ n = *bufpos;
+ oneline = 0;
+ }
+ 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)
@@ -2029,6 +2036,7 @@ 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\
@@ -2066,7 +2074,7 @@ 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 source] [-T keyword] [-V rtable] [-W recvlimit] "
"[-w timeout]\n"
|