diff options
Diffstat (limited to 'toys/net/netcat.c')
| -rw-r--r-- | toys/net/netcat.c | 107 |
1 files changed, 50 insertions, 57 deletions
diff --git a/toys/net/netcat.c b/toys/net/netcat.c index 2d80a18f..38348949 100644 --- a/toys/net/netcat.c +++ b/toys/net/netcat.c @@ -2,47 +2,35 @@ * * Copyright 2007 Rob Landley <rob@landley.net> * - * TODO: udp, ipv6, genericize for telnet/microcom/tail-f - * fix -t, xconnect - * netcat -L zombies + * TODO: genericize for telnet/microcom/tail-f, fix -t +USE_NETCAT(NEWTOY(netcat, "^tElLw#<1W#<1p#<1>65535q#<1s:f:46uUn[!tlL][!Lw][!Lu][!46U]", TOYFLAG_BIN)) USE_NETCAT(OLDTOY(nc, netcat, TOYFLAG_USR|TOYFLAG_BIN)) -USE_NETCAT(NEWTOY(netcat, USE_NETCAT_LISTEN("^tElL")"w#<1W#<1p#<1>65535q#<1s:f:46uU"USE_NETCAT_LISTEN("[!tlL][!Lw]")"[!46U]", TOYFLAG_BIN)) config NETCAT bool "netcat" default y help - usage: netcat [-46U] [-u] [-wpq #] [-s addr] {IPADDR PORTNUM|-f FILENAME|COMMAND...} + usage: netcat [-46ElLtUu] [-wpq #] [-s addr] {IPADDR PORTNUM|-f FILENAME|COMMAND...} Forward stdin/stdout to a file or network connection. -4 Force IPv4 -6 Force IPv6 + -E Forward stderr -f Use FILENAME (ala /dev/ttyS0) instead of network + -l Listen for one incoming connection, then exit + -L Listen and background each incoming connection (server mode) + -n No DNS lookup -p Local port number -q Quit SECONDS after EOF on stdin, even if stdout hasn't closed yet -s Local source address + -t Allocate tty -u Use UDP -U Use a UNIX domain socket -w SECONDS timeout to establish connection -W SECONDS timeout for more data on an idle connection - Use "stty 115200 -F /dev/ttyS0 && stty raw -echo -ctlecho" with - netcat -f to connect to a serial port. - -config NETCAT_LISTEN - bool "netcat server options (-let)" - default y - depends on NETCAT - help - usage: netcat [-tElL] - - -l Listen for one incoming connection, then exit - -L Listen and background each incoming connection (server mode) - -t Allocate tty - -E Forward stderr - When listening the COMMAND line is executed as a child process to handle an incoming connection. With no COMMAND -l forwards the connection to stdin/stdout. If no -p specified, -l prints the port it bound to and @@ -50,6 +38,9 @@ config NETCAT_LISTEN For a quick-and-dirty server, try something like: netcat -s 127.0.0.1 -p 1234 -tL sh -l + + Or use "stty 115200 -F /dev/ttyS0 && stty raw -echo -ctlecho" with + netcat -f to connect to a serial port. */ #define FOR_netcat @@ -66,12 +57,6 @@ static void timeout(int signum) xexit(); } -static void set_alarm(int seconds) -{ - xsignal(SIGALRM, seconds ? timeout : SIG_DFL); - alarm(seconds); -} - // open AF_UNIX socket static int usock(char *name, int type, int out) { @@ -90,12 +75,12 @@ static int usock(char *name, int type, int out) return sockfd; } - void netcat_main(void) { int sockfd = -1, in1 = 0, in2 = 0, out1 = 1, out2 = 1, family = AF_UNSPEC, - ll = FLAG(L)|FLAG(l), type = FLAG(u) ? SOCK_DGRAM : SOCK_STREAM; + type = FLAG(u) ? SOCK_DGRAM : SOCK_STREAM; + socklen_t len; pid_t child; // Addjust idle and quit_delay to ms or -1 for no timeout @@ -103,11 +88,14 @@ void netcat_main(void) TT.q = TT.q ? TT.q*1000 : -1; xsignal(SIGCHLD, SIG_IGN); - set_alarm(TT.w); + if (TT.w) { + xsignal(SIGALRM, timeout); + alarm(TT.w); + } // The argument parsing logic can't make "<2" conditional on other // arguments like -f and -l, so do it by hand here. - if (FLAG(f) ? toys.optc : (!ll && toys.optc!=(FLAG(U)?1:2))) + if (FLAG(f) ? toys.optc : (!FLAG(l) && !FLAG(L) && toys.optc!=2-FLAG(U))) help_exit("bad argument count"); if (FLAG(4)) family = AF_INET; @@ -117,13 +105,13 @@ void netcat_main(void) if (TT.f) in1 = out2 = xopen(TT.f, O_RDWR); else { // Setup socket - if (!ll) { + if (!FLAG(l) && !FLAG(L)) { if (FLAG(U)) sockfd = usock(toys.optargs[0], type, 1); - else sockfd = xconnectany(xgetaddrinfo(toys.optargs[0], toys.optargs[1], - family, type, 0, 0)); + else sockfd = xconnectany(xgetaddrinfo(toys.optargs[0], + toys.optargs[1], family, type, 0, AI_NUMERICHOST*FLAG(n))); // We have a connection. Disarm timeout and start poll/send loop. - set_alarm(0); + alarm(0); in1 = out2 = sockfd; pollinate(in1, in2, out1, out2, TT.W, TT.q); } else { @@ -136,12 +124,12 @@ void netcat_main(void) sockfd = xbindany(xgetaddrinfo(TT.s, toybuf, family, type, 0, 0)); } - if (listen(sockfd, 5)) error_exit("listen"); + if (!FLAG(u) && listen(sockfd, 5)) perror_exit("listen"); if (!TT.p && !FLAG(U)) { struct sockaddr* address = (void*)toybuf; - socklen_t len = sizeof(struct sockaddr_storage); short port_be; + len = sizeof(struct sockaddr_storage); getsockname(sockfd, address, &len); if (address->sa_family == AF_INET) port_be = ((struct sockaddr_in*)address)->sin_port; @@ -156,41 +144,46 @@ void netcat_main(void) } do { + len = sizeof(struct sockaddr_storage); + if (FLAG(u)) { + if (-1 == recvfrom(in1 = dup(sockfd), &child, 1, MSG_PEEK, + (void *)toybuf, &len)) perror_exit("recvfrom"); + } else if ((in1 = accept(sockfd, 0, 0))<0) perror_exit("accept"); + out2 = in1; child = 0; - in1 = out2 = accept(sockfd, 0, 0); - if (in1<0) perror_exit("accept"); // We have a connection. Disarm timeout. - set_alarm(0); - - if (toys.optc) { - // Do we need a tty? + alarm(0); -// TODO nommu, and -t only affects server mode...? Only do -t with optc -// if (CFG_TOYBOX_FORK && (toys.optflags&FLAG_t)) -// child = forkpty(&fdout, NULL, NULL, NULL); -// else + // Fork a child as necessary. Parent cleans up and continues here. + if (toys.optc && FLAG(L)) NOEXIT(child = XVFORK()); + if (child) { + close(in1); + continue; + } - // Do we need to fork and/or redirect for exec? + if (FLAG(u)) + xconnect(in1, (void *)toybuf, sizeof(struct sockaddr_storage)); -// TODO xpopen_both() here? + // Cleanup and redirect for exec + if (toys.optc) { + // Do we need a tty? +// TODO nommu and -t only affects server mode... +// if (FLAG(t)) child = forkpty(&fdout, NULL, NULL, NULL); - if (FLAG(L)) NOEXIT(child = XVFORK()); - if (child) { - close(in1); - continue; - } close(sockfd); dup2(in1, 0); dup2(in1, 1); if (FLAG(E)) dup2(in1, 2); if (in1>2) close(in1); xexec(toys.optargs); - } - pollinate(in1, in2, out1, out2, TT.W, TT.q); - close(in1); - } while (!FLAG(l)); + // Copy stdin/out + } else { + pollinate(in1, in2, out1, out2, TT.W, TT.q); + close(in1); + } + } while (FLAG(L)); } } |