diff options
Diffstat (limited to 'toys')
| -rw-r--r-- | toys/Config.in | 22 | ||||
| -rw-r--r-- | toys/netcat.c | 116 | ||||
| -rw-r--r-- | toys/toylist.h | 13 |
3 files changed, 150 insertions, 1 deletions
diff --git a/toys/Config.in b/toys/Config.in index 7c75d255..a53c11f1 100644 --- a/toys/Config.in +++ b/toys/Config.in @@ -226,7 +226,27 @@ config MKFIFO Makes a named pipe at name. -m mode The mode of the pipe(s) created by mkfifo. It defaults to 0644. - The format is in octal, optionally preceded by a leading zero. + The format is in octal, optionally preceded by a leading zero. + +config NETCAT + bool "netcat" + default y + help + usage: netcat [-iwlp] {IPADDR PORTNUM|-f FILENAME} [-e COMMAND] + + -e exec the rest of the command line + -i SECONDS delay after each line sent + -w SECONDS timeout for connection + -f filename use file (ala /dev/ttyS0) instead of network + -l listen for incoming connection (twice for persistent connection) + -p local port number + -s local source address + -q SECONDS quit this many seconds after EOF on stdin. + + Use -l twice with -e for a quick-and-dirty server. + + Use "stty 115200 -F /dev/ttyS0 && stty raw -echo -ctlecho" with + netcat -f to connect to a serial port. config ONEIT bool "oneit" diff --git a/toys/netcat.c b/toys/netcat.c new file mode 100644 index 00000000..39c531d8 --- /dev/null +++ b/toys/netcat.c @@ -0,0 +1,116 @@ +/* vi: set sw=4 ts=4: */ +/* nc: mini-netcat - Forward stdin/stdout to a file or network connection. + * + * Copyright 2007 Rob Landley <rob@landley.net> + */ + +#include "toys.h" +#include "toynet.h" + +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> + +#define TT toy.netcat + +static void timeout(int signum) +{ + error_exit("Timeout"); +} + +// Translate x.x.x.x numeric IPv4 address, or else DNS lookup an IPv4 name. +void lookup_name(char *name, uint32_t *result) +{ + struct hostent *hostbyname; + + hostbyname = gethostbyname(*toys.optargs); + if (!hostbyname) error_exit("name lookup failed"); + *result = *(uint32_t *)*hostbyname->h_addr_list; +} + +// Worry about a fancy lookup later. +void lookup_port(char *str, uint16_t *port) +{ + *port = SWAP_BE16(atoi(str)); +} + +void netcat_main(void) +{ + int sockfd, pollcount; + struct pollfd pollfds[2]; + + if (TT.wait) { + signal(SIGALRM, timeout); + alarm(TT.wait); + } + + if (TT.filename) pollfds[0].fd = xopen(TT.filename, O_RDWR); + else { + int temp; + struct sockaddr_in address; + + // The argument parsing logic can't make "<2" conditional on "-f", so... + if (!*toys.optargs || !toys.optargs[1]) { + toys.exithelp++; + error_exit("Need address and port"); + } + + // Setup socket + sockfd = socket(AF_INET, SOCK_STREAM, 0); + if (-1 == sockfd) perror_exit("socket"); + fcntl(sockfd, F_SETFD, FD_CLOEXEC); + temp = 1; + setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &temp, sizeof(temp)); + memset(&address, 0, sizeof(address)); + address.sin_family = AF_INET; + if (TT.port) { + address.sin_port = TT.port; + if (-1 == bind(sockfd, &address, sizeof(address))) + perror_exit("bind"); + } + + // Figure out where to dial out to. + lookup_name(*toys.optargs, (uint32_t *)&address.sin_addr); + lookup_port(toys.optargs[1], &address.sin_port); + temp = connect(sockfd, (struct sockaddr *)&address, sizeof(address)); + if (temp<0) perror_exit("connect"); + pollfds[0].fd = sockfd; + } + + // We have a connection. Disarm timeout. + if (TT.wait) { + alarm(0); + signal(SIGALRM, SIG_DFL); + } + + pollcount = 2; + pollfds[1].fd = 0; + pollfds[0].events = pollfds[1].events = POLLIN; + + // Poll loop copying stdin->socket and socket->stdout. + for (;;) { + int i; + + if (0>poll(pollfds, pollcount, -1)) perror_exit("poll"); + + for (i=0; i<pollcount; i++) { + if (pollfds[i].revents & POLLIN) { + int len = read(pollfds[i].fd, toybuf, sizeof(toybuf)); + if (len<1) goto dohupnow; + xwrite(i ? pollfds[0].fd : 1, toybuf, len); + } + if (pollfds[i].revents & POLLHUP) { +dohupnow: + // Close half-connect. This is needed for things like + // "echo GET / | netcat landley.net 80" to work. + if (i) { + shutdown(pollfds[0].fd, SHUT_WR); + pollcount--; + } else goto cleanup; + } + } + } +cleanup: + close(pollfds[0].fd); +// close(sockfd); +} diff --git a/toys/toylist.h b/toys/toylist.h index e3fb4d7c..360efa8a 100644 --- a/toys/toylist.h +++ b/toys/toylist.h @@ -53,6 +53,16 @@ struct mke2fs_data { struct ext2_superblock sb; }; +struct netcat_data { + char *filename; // -f read from filename instead of network + long quit_delay; // -q Exit after EOF from stdin after # seconds. + char *source_address; // -s Bind to a specific source address. + long port; // -p Bind to a specific source port. + long listen; // -l Listen for connection instead of dialing out. + long wait; // -w Wait # seconds for a connection. + long delay; // -i delay between lines sent +}; + struct sleep_data { long seconds; }; @@ -76,6 +86,7 @@ extern union toy_union { struct df_data df; struct mke2fs_data mke2fs; struct mkfifo_data mkfifo; + struct netcat_data netcat; struct sleep_data sleep; struct touch_data touch; struct toysh_data toysh; @@ -120,6 +131,8 @@ USE_HELLO(NEWTOY(hello, NULL, TOYFLAG_USR|TOYFLAG_BIN)) USE_HELP(NEWTOY(help, "<1", TOYFLAG_BIN)) USE_MKE2FS(NEWTOY(mke2fs, MKE2FS_OPTSTRING, TOYFLAG_SBIN)) USE_MKFIFO(NEWTOY(mkfifo, "<1m:", TOYFLAG_BIN)) +USE_NETCAT(OLDTOY(nc, netcat, "i#w#l@p#s:q#f:e", TOYFLAG_BIN)) +USE_NETCAT(NEWTOY(netcat, "i#w#l@p#s:q#f:e", TOYFLAG_BIN)) USE_ONEIT(NEWTOY(oneit, "+<1p", TOYFLAG_SBIN)) USE_PWD(NEWTOY(pwd, NULL, TOYFLAG_BIN)) USE_READLINK(NEWTOY(readlink, "<1f", TOYFLAG_BIN)) |