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| | From: Aron Xu <aron@debian.org>
Date: Mon, 13 Feb 2012 15:56:51 +0800
Subject: dccp support
---
nc.1 | 4 ++
netcat.c | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++++----------
2 files changed, 79 insertions(+), 14 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 46CDdFhklNnrStUuvz
+.Op Fl 46CDdFhklNnrStUuvZz
.Op Fl I Ar length
.Op Fl i Ar interval
.Op Fl M Ar ttl
@@ -289,6 +289,8 @@ An IPv6 address can be specified unambig
in square brackets.
A proxy cannot be used with any of the options
.Fl lsuU .
+.It Fl Z
+DCCP mode.
.It Fl z
Only scan for listening daemons, without sending any data to them.
Cannot be used together with
--- a/netcat.c
+++ b/netcat.c
@@ -146,6 +146,7 @@ int rflag; /* Random ports flag */
char *sflag; /* Source Address */
int tflag; /* Telnet Emulation */
int uflag; /* UDP - Default to TCP */
+int dccpflag; /* DCCP - Default to TCP */
int vflag; /* Verbosity */
int xflag; /* Socks proxy */
int zflag; /* Port Scan Flag */
@@ -224,6 +225,7 @@ ssize_t drainbuf(int, unsigned char *, s
ssize_t fillbuf(int, unsigned char *, size_t *);
# endif
+char *proto_name(int uflag, int dccpflag);
static int connect_with_timeout(int fd, const struct sockaddr *sa,
socklen_t salen, int ctimeout);
@@ -263,7 +265,7 @@ main(int argc, char *argv[])
# if defined(TLS)
"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:q:rSs:T:tUuV:vW:w:X:x:z"))
+ "46CDdFhI:i:klM:m:NnO:P:p:q:rSs:T:tUuV:vW:w:X:x:Zz"))
# endif
!= -1) {
switch (ch) {
@@ -380,6 +382,13 @@ main(int argc, char *argv[])
case 'u':
uflag = 1;
break;
+ case 'Z':
+# if defined(IPPROTO_DCCP) && defined(SOCK_DCCP)
+ dccpflag = 1;
+# else
+ errx(1, "no DCCP support available");
+# endif
+ break;
case 'V':
# if defined(RT_TABLEID_MAX)
rtableid = (int)strtonum(optarg, 0,
@@ -484,6 +493,10 @@ main(int argc, char *argv[])
/* Cruft to make sure options are clean, and used properly. */
if (argv[0] && !argv[1] && family == AF_UNIX) {
+# if defined(IPPROTO_DCCP) && defined(SOCK_DCCP)
+ if (dccpflag)
+ errx(1, "cannot use -Z and -U");
+# endif
host = argv[0];
uport = NULL;
} else if (!argv[0] && lflag) {
@@ -577,8 +590,20 @@ main(int argc, char *argv[])
if (family != AF_UNIX) {
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = family;
- hints.ai_socktype = uflag ? SOCK_DGRAM : SOCK_STREAM;
- hints.ai_protocol = uflag ? IPPROTO_UDP : IPPROTO_TCP;
+ if (uflag) {
+ hints.ai_socktype = SOCK_DGRAM;
+ hints.ai_protocol = IPPROTO_UDP;
+ }
+# if defined(IPPROTO_DCCP) && defined(SOCK_DCCP)
+ else if (dccpflag) {
+ hints.ai_socktype = SOCK_DCCP;
+ hints.ai_protocol = IPPROTO_DCCP;
+ }
+# endif
+ else {
+ hints.ai_socktype = SOCK_STREAM;
+ hints.ai_protocol = IPPROTO_TCP;
+ }
if (nflag)
hints.ai_flags |= AI_NUMERICHOST;
}
@@ -586,7 +611,10 @@ main(int argc, char *argv[])
if (xflag) {
if (uflag)
errx(1, "no proxy support for UDP mode");
-
+# if defined(IPPROTO_DCCP) && defined(SOCK_DCCP)
+ if (dccpflag)
+ errx(1, "no proxy support for DCCP mode");
+# endif
if (lflag)
errx(1, "no proxy support for listen");
@@ -833,19 +861,20 @@ main(int argc, char *argv[])
}
}
+ char *proto = proto_name(uflag, dccpflag);
/* Don't look up port if -n. */
if (nflag)
sv = NULL;
else {
sv = getservbyport(
ntohs(atoi(portlist[i])),
- uflag ? "udp" : "tcp");
+ proto);
}
fprintf(stderr,
"Connection to %s %s port [%s/%s] "
"succeeded!\n", host, portlist[i],
- uflag ? "udp" : "tcp",
+ proto,
sv ? sv->s_name : "*");
}
if (Fflag)
@@ -1060,6 +1089,24 @@ unix_listen(char *path)
return s;
}
+char *proto_name(int uflag, int dccpflag) {
+
+ char *proto = NULL;
+ if (uflag) {
+ proto = "udp";
+ }
+# if defined(IPPROTO_DCCP) && defined(SOCK_DCCP)
+ else if (dccpflag) {
+ proto = "dccp";
+ }
+# endif
+ else {
+ proto = "tcp";
+ }
+
+ return proto;
+}
+
/*
* remote_connect()
* Returns a socket connected to a remote host. Properly binds to a local
@@ -1090,8 +1137,21 @@ remote_connect(const char *host, const c
# endif
memset(&ahints, 0, sizeof(struct addrinfo));
ahints.ai_family = res->ai_family;
- ahints.ai_socktype = uflag ? SOCK_DGRAM : SOCK_STREAM;
- ahints.ai_protocol = uflag ? IPPROTO_UDP : IPPROTO_TCP;
+ if (uflag) {
+ ahints.ai_socktype = SOCK_DGRAM;
+ ahints.ai_protocol = IPPROTO_UDP;
+
+ }
+# if defined(IPPROTO_DCCP) && defined(SOCK_DCCP)
+ else if (dccpflag) {
+ hints.ai_socktype = SOCK_DCCP;
+ hints.ai_protocol = IPPROTO_DCCP;
+ }
+# endif
+ else {
+ ahints.ai_socktype = SOCK_STREAM;
+ ahints.ai_protocol = IPPROTO_TCP;
+ }
ahints.ai_flags = AI_PASSIVE;
if ((error = getaddrinfo(sflag, pflag, &ahints, &ares)))
errx(1, "getaddrinfo: %s", gai_strerror(error));
@@ -1103,15 +1163,16 @@ remote_connect(const char *host, const c
}
set_common_sockopts(s, res->ai_family);
+ char *proto = proto_name(uflag, dccpflag);
if ((error = connect_with_timeout(s, res->ai_addr, res->ai_addrlen, timeout)) == CONNECTION_SUCCESS)
break;
if (vflag && error == CONNECTION_FAILED)
warn("connect to %s port %s (%s) failed", host, port,
- uflag ? "udp" : "tcp");
- else if (vflag && error == CONNECTION_TIMEOUT)
+ proto);
+ else if (vflag && error == CONNECTION_TIMEOUT)
warn("connect to %s port %s (%s) timed out", host, port,
- uflag ? "udp" : "tcp");
+ proto);
save_errno = errno;
close(s);
@@ -1715,7 +1776,8 @@ build_ports(char *p)
int hi, lo, cp;
int x = 0;
- sv = getservbyname(p, uflag ? "udp" : "tcp");
+ char *proto = proto_name(uflag, dccpflag);
+ sv = getservbyname(p, proto);
if (sv) {
if (asprintf(&portlist[0], "%d", ntohs(sv->s_port)) < 0)
err(1, "asprintf");
@@ -2095,6 +2157,7 @@ help(void)
\t-w timeout Timeout for connects and final net reads\n\
\t-X proto Proxy protocol: \"4\", \"5\" (SOCKS) or \"connect\"\n\
\t-x addr[:port]\tSpecify proxy address and port\n\
+ \t-Z DCCP mode\n\
\t-z Zero-I/O mode [used for scanning]\n\
Port numbers can be individual or ranges: lo-hi [inclusive]\n");
exit(0);
@@ -2104,7 +2167,7 @@ void
usage(int ret)
{
fprintf(stderr,
- "usage: nc [-46CDdFhklNnrStUuvz] [-I length] [-i interval] [-M ttl]\n"
+ "usage: nc [-46CDdFhklNnrStUuvZz] [-I length] [-i interval] [-M ttl]\n"
"\t [-m minttl] [-O length] [-P proxy_username] [-p source_port]\n"
"\t [-q seconds] [-s source] [-T keyword] [-V rtable] [-W recvlimit] "
"[-w timeout]\n"
|