From: Aron Xu Date: Mon, 13 Feb 2012 15:56:51 +0800 Subject: dccp support --- nc.1 | 4 ++- netcat.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++++----------- 2 files changed, 88 insertions(+), 18 deletions(-) diff --git a/nc.1 b/nc.1 index 1ee6887..fe42909 100644 --- a/nc.1 +++ b/nc.1 @@ -34,7 +34,7 @@ .Sh SYNOPSIS .Nm nc .Bk -words -.Op Fl 46CDdFhklNnrStUuvz +.Op Fl 46CDdFhklNnrStUuvZz .Op Fl I Ar length .Op Fl i Ar interval .Op Fl O Ar length @@ -279,6 +279,8 @@ If .Ar port is not specified, the well-known port for the proxy protocol is used (1080 for SOCKS, 3128 for HTTPS). +.It Fl Z +DCCP mode. .It Fl z Specifies that .Nm diff --git a/netcat.c b/netcat.c index 3240a08..f4d85af 100644 --- a/netcat.c +++ b/netcat.c @@ -136,6 +136,7 @@ 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 */ @@ -171,6 +172,7 @@ void report_connect(const struct sockaddr *, socklen_t); void usage(int); ssize_t drainbuf(int, unsigned char *, size_t *, int); ssize_t fillbuf(int, unsigned char *, size_t *); +char *proto_name(int uflag, int dccpflag); static int connect_with_timeout(int fd, const struct sockaddr *sa, socklen_t salen, int ctimeout); @@ -200,7 +202,7 @@ main(int argc, char *argv[]) signal(SIGPIPE, SIG_IGN); while ((ch = getopt(argc, argv, - "46CDdFhI:i:klNnO:P:p:q:rSs:tT:UuV:vw:X:x:z")) != -1) { + "46CDdFhI:i:klNnO:P:p:q:rSs:tT:UuV:vw:X:x:Zz")) != -1) { switch (ch) { case '4': family = AF_INET; @@ -270,6 +272,13 @@ 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, @@ -345,6 +354,12 @@ main(int argc, char *argv[]) /* Cruft to make sure options are clean, and used properly. */ if (argv[0] && !argv[1] && family == AF_UNIX) { + if (uflag) + errx(1, "cannot use -u and -U"); +# 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) { @@ -386,8 +401,20 @@ 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; } @@ -395,7 +422,10 @@ 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"); @@ -439,12 +469,12 @@ main(int argc, char *argv[]) err(1, NULL); char* local; - if (family == AF_INET6 + if (family == AF_INET6 ) local = "0.0.0.0"; else if (family == AF_INET) local = ":::"; else - local = "unknown" + local = "unknown"; fprintf(stderr, "Listening on [%s] (family %d, port %d)\n", host ?: local, family, @@ -549,19 +579,20 @@ 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) @@ -663,6 +694,24 @@ 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 @@ -699,8 +748,21 @@ remote_connect(const char *host, const char *port, struct addrinfo hints) # endif memset(&ahints, 0, sizeof(struct addrinfo)); ahints.ai_family = res0->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)); @@ -712,15 +774,19 @@ remote_connect(const char *host, const char *port, struct addrinfo hints) } set_common_sockopts(s, res0->ai_family); + char *proto = proto_name(uflag, dccpflag); - if ((error = connect_with_timeout(s, res0->ai_addr, res0->ai_addrlen, timeout))== CONNECTION_SUCCESS) + if ((error = connect_with_timeout(s, res0->ai_addr, res0->ai_addrlen, timeout))== CONNECTION_SUCCESS) { break; - else if (vflag && error == CONNECTION_FAILED) + } + else 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); + } close(s); s = -1; @@ -1250,7 +1316,8 @@ 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) { portlist[0] = calloc(1, PORT_MAX_LEN); if (portlist[0] == NULL) @@ -1484,6 +1551,7 @@ help(void) \t-w secs\t 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); @@ -1493,7 +1561,7 @@ void usage(int ret) { fprintf(stderr, - "usage: nc [-46CDdFhklNnrStUuvz] [-I length] [-i interval] [-O length]\n" + "usage: nc [-46CDdFhklNnrStUuvZz] [-I length] [-i interval] [-O length]\n" "\t [-P proxy_username] [-p source_port] [-q seconds] [-s source]\n" "\t [-T toskeyword] [-V rtable] [-w timeout] [-X proxy_protocol]\n" "\t [-x proxy_address[:port]] [destination] [port]\n"); --