From: Aron Xu 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 @@ -147,6 +147,7 @@ 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 */ @@ -225,6 +226,7 @@ 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); @@ -261,7 +263,7 @@ 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) { @@ -378,6 +380,13 @@ 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, @@ -482,6 +491,10 @@ 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) { @@ -575,8 +588,20 @@ 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; } @@ -584,7 +609,10 @@ 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"); @@ -841,19 +869,20 @@ 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) @@ -1063,6 +1092,24 @@ 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 @@ -1093,8 +1140,21 @@ 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)); @@ -1106,15 +1166,16 @@ 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); @@ -1706,7 +1767,8 @@ 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"); @@ -2090,6 +2152,7 @@ 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); @@ -2099,7 +2162,7 @@ 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"