X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=networking%2Fnc_bloaty.c;h=62a025116561974d89b5e3e0b6bc21e7ded63fd7;hb=3f21044f20ef304309651bbdef8b275475f03a28;hp=cd014781be5feb1c620e6015f26fb97ccc9198c6;hpb=574f2f43948bb21d6e4187936ba5a5afccba25f6;p=oweals%2Fbusybox.git diff --git a/networking/nc_bloaty.c b/networking/nc_bloaty.c index cd014781b..62a025116 100644 --- a/networking/nc_bloaty.c +++ b/networking/nc_bloaty.c @@ -3,7 +3,7 @@ * * Copyright (C) 2007 Denys Vlasenko. * - * Licensed under GPLv2, see file LICENSE in this tarball for details. + * Licensed under GPLv2, see file LICENSE in this source tree. */ /* Author's comments from nc 1.10: @@ -36,20 +36,58 @@ * - source routing * - multiple DNS checks * Functionalty which is different from nc 1.10: - * - Prog in '-e prog' can have prog's parameters and options. + * - PROG in '-e PROG' can have ARGS (and options). * Because of this -e option must be last. - * - nc doesn't redirect stderr to the network socket for the -e prog. +//TODO: remove -e incompatibility? + * - we don't redirect stderr to the network socket for the -e PROG. + * (PROG can do it itself if needed, but sometimes it is NOT wanted!) * - numeric addresses are printed in (), not [] (IPv6 looks better), * port numbers are inside (): (1.2.3.4:5678) * - network read errors are reported on verbose levels > 1 * (nc 1.10 treats them as EOF) * - TCP connects from wrong ip/ports (if peer ip:port is specified * on the command line, but accept() says that it came from different addr) - * are closed, but nc doesn't exit - continues to listen/accept. + * are closed, but we don't exit - we continue to listen/accept. */ /* done in nc.c: #include "libbb.h" */ +//usage:#if ENABLE_NC_110_COMPAT +//usage: +//usage:#define nc_trivial_usage +//usage: "[OPTIONS] HOST PORT - connect" +//usage: IF_NC_SERVER("\n" +//usage: "nc [OPTIONS] -l -p PORT [HOST] [PORT] - listen" +//usage: ) +//usage:#define nc_full_usage "\n\n" +//usage: " -e PROG Run PROG after connect (must be last)" +//usage: IF_NC_SERVER( +//usage: "\n -l Listen mode, for inbound connects" +//usage: ) +//usage: "\n -p PORT Local port" +//usage: "\n -s ADDR Local address" +//usage: "\n -w SEC Timeout for connects and final net reads" +//usage: IF_NC_EXTRA( +//usage: "\n -i SEC Delay interval for lines sent" /* ", ports scanned" */ +//usage: ) +//usage: "\n -n Don't do DNS resolution" +//usage: "\n -u UDP mode" +//usage: "\n -v Verbose" +//usage: IF_NC_EXTRA( +//usage: "\n -o FILE Hex dump traffic" +//usage: "\n -z Zero-I/O mode (scanning)" +//usage: ) +//usage:#endif + +/* "\n -r Randomize local and remote ports" */ +/* "\n -g gateway Source-routing hop point[s], up to 8" */ +/* "\n -G num Source-routing pointer: 4, 8, 12, ..." */ +/* "\nport numbers can be individual or ranges: lo-hi [inclusive]" */ + +/* -e PROG can take ARGS too: "nc ... -e ls -l", but we don't document it + * in help text: nc 1.10 does not allow that. We don't want to entice + * users to use this incompatibility */ + enum { SLEAZE_PORT = 31337, /* for UDP-scan RTT trick, change if ya want */ BIGSIZ = 8192, /* big buffers */ @@ -77,6 +115,7 @@ struct globals { unsigned wrote_out; /* total stdout bytes */ unsigned wrote_net; /* total net bytes */ #endif + char *proggie0saved; /* ouraddr is never NULL and goes through three states as we progress: 1 - local address before bind (IP/port possibly zero) 2 - local address after bind (port is nonzero) @@ -89,7 +128,6 @@ struct globals { jmp_buf jbuf; /* timer crud */ - /* will malloc up the following globals: */ fd_set ding1; /* for select loop */ fd_set ding2; char bigbuf_in[BIGSIZ]; /* data buffers */ @@ -121,17 +159,16 @@ struct globals { /* Must match getopt32 call! */ enum { - OPT_h = (1 << 0), - OPT_n = (1 << 1), - OPT_p = (1 << 2), - OPT_s = (1 << 3), - OPT_u = (1 << 4), - OPT_v = (1 << 5), - OPT_w = (1 << 6), - OPT_l = (1 << 7) * ENABLE_NC_SERVER, - OPT_i = (1 << (7+ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, - OPT_o = (1 << (8+ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, - OPT_z = (1 << (9+ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, + OPT_n = (1 << 0), + OPT_p = (1 << 1), + OPT_s = (1 << 2), + OPT_u = (1 << 3), + OPT_v = (1 << 4), + OPT_w = (1 << 5), + OPT_l = (1 << 6) * ENABLE_NC_SERVER, + OPT_i = (1 << (6+ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, + OPT_o = (1 << (7+ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, + OPT_z = (1 << (8+ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, }; #define o_nflag (option_mask32 & OPT_n) @@ -152,7 +189,7 @@ enum { /* Debug: squirt whatever message and sleep a bit so we can see it go by. */ /* Beware: writes to stdOUT... */ #if 0 -#define Debug(...) do { printf(__VA_ARGS__); printf("\n"); fflush(stdout); sleep(1); } while (0) +#define Debug(...) do { printf(__VA_ARGS__); printf("\n"); fflush_all(); sleep(1); } while (0) #else #define Debug(...) do { } while (0) #endif @@ -177,7 +214,7 @@ static void unarm(void) } /* timeout and other signal handling cruft */ -static void tmtravel(int sig) +static void tmtravel(int sig UNUSED_PARAM) { unarm(); longjmp(jbuf, 1); @@ -222,15 +259,16 @@ Debug("findline returning whole thing: %d", siz); that would be security-critical, which is why it's ifdefed out by default. Use at your own hairy risk; if you leave shells lying around behind open listening ports you deserve to lose!! */ -static int doexec(char **proggie) ATTRIBUTE_NORETURN; +static int doexec(char **proggie) NORETURN; static int doexec(char **proggie) { + if (G.proggie0saved) + proggie[0] = G.proggie0saved; xmove_fd(netfd, 0); dup2(0, 1); /* dup2(0, 2); - do we *really* want this? NO! * exec'ed prog can do it yourself, if needed */ - execvp(proggie[0], proggie); - bb_perror_msg_and_die("exec"); + BB_EXECVP_or_die(proggie); } /* connect_w_timeout: @@ -278,9 +316,9 @@ static void dolisten(void) random unknown port is probably not very useful without "netstat". */ if (o_verbose) { char *addr; - rr = getsockname(netfd, &ouraddr->u.sa, &ouraddr->len); - if (rr < 0) - bb_perror_msg_and_die("getsockname after bind"); + getsockname(netfd, &ouraddr->u.sa, &ouraddr->len); + //if (rr < 0) + // bb_perror_msg_and_die("getsockname after bind"); addr = xmalloc_sockaddr2dotted(&ouraddr->u.sa); fprintf(stderr, "listening on %s ...\n", addr); free(addr); @@ -340,16 +378,29 @@ create new one, and bind() it. TODO */ rr = accept(netfd, &remend.u.sa, &remend.len); if (rr < 0) bb_perror_msg_and_die("accept"); - if (themaddr && memcmp(&remend.u.sa, &themaddr->u.sa, remend.len) != 0) { - /* nc 1.10 bails out instead, and its error message - * is not suppressed by o_verbose */ - if (o_verbose) { - char *remaddr = xmalloc_sockaddr2dotted(&remend.u.sa); - bb_error_msg("connect from wrong ip/port %s ignored", remaddr); - free(remaddr); + if (themaddr) { + int sv_port, port, r; + + sv_port = get_nport(&remend.u.sa); /* save */ + port = get_nport(&themaddr->u.sa); + if (port == 0) { + /* "nc -nl -p LPORT RHOST" (w/o RPORT!): + * we should accept any remote port */ + set_nport(&remend.u.sa, 0); /* blot out remote port# */ + } + r = memcmp(&remend.u.sa, &themaddr->u.sa, remend.len); + set_nport(&remend.u.sa, sv_port); /* restore */ + if (r != 0) { + /* nc 1.10 bails out instead, and its error message + * is not suppressed by o_verbose */ + if (o_verbose) { + char *remaddr = xmalloc_sockaddr2dotted(&remend.u.sa); + bb_error_msg("connect from wrong ip/port %s ignored", remaddr); + free(remaddr); + } + close(rr); + goto again; } - close(rr); - goto again; } unarm(); } else @@ -359,9 +410,9 @@ create new one, and bind() it. TODO */ doing a listen-on-any on a multihomed machine. This allows one to offer different services via different alias addresses, such as the "virtual web site" hack. */ - rr = getsockname(netfd, &ouraddr->u.sa, &ouraddr->len); - if (rr < 0) - bb_perror_msg_and_die("getsockname after accept"); + getsockname(netfd, &ouraddr->u.sa, &ouraddr->len); + //if (rr < 0) + // bb_perror_msg_and_die("getsockname after accept"); } if (o_verbose) { @@ -374,14 +425,11 @@ create new one, and bind() it. TODO */ thing to emerge after all the intervening crud. Doesn't work for UDP on any machines I've tested, but feel free to surprise me. */ char optbuf[40]; - int x = sizeof(optbuf); + socklen_t x = sizeof(optbuf); rr = getsockopt(netfd, IPPROTO_IP, IP_OPTIONS, optbuf, &x); - if (rr < 0) - bb_perror_msg("getsockopt failed"); - else if (x) { /* we've got options, lessee em... */ - bin2hex(bigbuf_net, optbuf, x); - bigbuf_net[2*x] = '\0'; + if (rr >= 0 && x) { /* we've got options, lessee em... */ + *bin2hex(bigbuf_net, optbuf, x) = '\0'; fprintf(stderr, "IP options: %s\n", bigbuf_net); } #endif @@ -437,7 +485,7 @@ static int udptest(void) us to hang forever, and hit it */ o_wait = 5; /* enough that we'll notice?? */ rr = xsocket(ouraddr->u.sa.sa_family, SOCK_STREAM, 0); - set_nport(themaddr, htons(SLEAZE_PORT)); + set_nport(&themaddr->u.sa, htons(SLEAZE_PORT)); connect_w_timeout(rr); /* don't need to restore themaddr's port, it's not used anymore */ close(rr); @@ -487,7 +535,7 @@ static void oprint(int direction, unsigned char *p, unsigned bc) memset(&stage[11], ' ', 16*3); x = bc; } - sprintf(&stage[1], " %8.8x ", obc); /* xxx: still slow? */ + sprintf((char *)&stage[1], " %8.8x ", obc); /* xxx: still slow? */ bc -= x; /* fix current count */ obc += x; /* fix current offset */ op = &stage[11]; /* where hex starts */ @@ -562,7 +610,7 @@ static int readwrite(void) /* if we have a timeout AND stdin is closed AND we haven't heard anything from the net during that time, assume it's dead and close it too. */ if (rr == 0) { - if (!FD_ISSET(0, &ding1)) + if (!FD_ISSET(STDIN_FILENO, &ding1)) netretry--; /* we actually try a coupla times. */ if (!netretry) { if (o_verbose > 1) /* normally we don't care */ @@ -597,13 +645,16 @@ Debug("got %d from the net, errno %d", rr, errno); goto shovel; /* okay, suck more stdin */ - if (FD_ISSET(0, &ding2)) { /* stdin: ding! */ - rr = read(0, bigbuf_in, BIGSIZ); + if (FD_ISSET(STDIN_FILENO, &ding2)) { /* stdin: ding! */ + rr = read(STDIN_FILENO, bigbuf_in, BIGSIZ); /* Considered making reads here smaller for UDP mode, but 8192-byte mobygrams are kinda fun and exercise the reassembler. */ if (rr <= 0) { /* at end, or fukt, or ... */ - FD_CLR(0, &ding1); /* disable and close stdin */ - close(0); + FD_CLR(STDIN_FILENO, &ding1); /* disable and close stdin */ + close(STDIN_FILENO); +// Does it make sense to shutdown(net_fd, SHUT_WR) +// to let other side know that we won't write anything anymore? +// (and what about keeping compat if we do that?) } else { rzleft = rr; zp = bigbuf_in; @@ -625,10 +676,10 @@ Debug("got %d from the net, errno %d", rr, errno); return 1; } if (rnleft) { - rr = write(1, np, rnleft); + rr = write(STDOUT_FILENO, np, rnleft); if (rr > 0) { - if (o_ofile) - oprint('<', np, rr); /* log the stdout */ + if (o_ofile) /* log the stdout */ + oprint('<', (unsigned char *)np, rr); np += rr; /* fix up ptrs and whatnot */ rnleft -= rr; /* will get sanity-checked above */ wrote_out += rr; /* global count */ @@ -642,8 +693,8 @@ Debug("wrote %d to stdout, errno %d", rr, errno); rr = rzleft; rr = write(netfd, zp, rr); /* one line, or the whole buffer */ if (rr > 0) { - if (o_ofile) - oprint('>', zp, rr); /* log what got sent */ + if (o_ofile) /* log what got sent */ + oprint('>', (unsigned char *)zp, rr); zp += rr; rzleft -= rr; wrote_net += rr; /* global count */ @@ -672,11 +723,11 @@ Debug("wrote %d to net, errno %d", rr, errno); /* main: now we pull it all together... */ int nc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; -int nc_main(int argc, char **argv) +int nc_main(int argc UNUSED_PARAM, char **argv) { - char *str_p, *str_s, *str_w; - USE_NC_EXTRA(char *str_i, *str_o;) - char *themdotted = themdotted; /* gcc */ + char *str_p, *str_s; + IF_NC_EXTRA(char *str_i, *str_o;) + char *themdotted = themdotted; /* for compiler */ char **proggie; int x; unsigned o_lport = 0; @@ -701,20 +752,33 @@ int nc_main(int argc, char **argv) while (*++proggie) { if (strcmp(*proggie, "-e") == 0) { *proggie = NULL; - argc = proggie - argv; proggie++; goto e_found; } + /* -e PROG [ARGS] ? */ + /* (aboriginal linux uses this form) */ + if (proggie[0][0] == '-') { + char *optpos = *proggie + 1; + /* Skip all valid opts w/o params */ + optpos = optpos + strspn(optpos, "nuv"IF_NC_SERVER("l")IF_NC_EXTRA("z")); + if (*optpos == 'e' && !optpos[1]) { + *optpos = '\0'; + proggie++; + G.proggie0saved = *proggie; + *proggie = NULL; /* terminate argv for getopt32 */ + goto e_found; + } + } } proggie = NULL; e_found: // -g -G -t -r deleted, unimplemented -a deleted too - opt_complementary = "?2:vv"; /* max 2 params, -v is a counter */ - getopt32(argv, "hnp:s:uvw:" USE_NC_SERVER("l") - USE_NC_EXTRA("i:o:z"), - &str_p, &str_s, &str_w - USE_NC_EXTRA(, &str_i, &str_o, &o_verbose)); + opt_complementary = "?2:vv:w+"; /* max 2 params; -v is a counter; -w N */ + getopt32(argv, "np:s:uvw:" IF_NC_SERVER("l") + IF_NC_EXTRA("i:o:z"), + &str_p, &str_s, &o_wait + IF_NC_EXTRA(, &str_i, &str_o), &o_verbose); argv += optind; #if ENABLE_NC_EXTRA if (option_mask32 & OPT_i) /* line-interval time */ @@ -731,9 +795,7 @@ int nc_main(int argc, char **argv) //if (option_mask32 & OPT_r) /* randomize various things */ //if (option_mask32 & OPT_u) /* use UDP */ //if (option_mask32 & OPT_v) /* verbose */ - if (option_mask32 & OPT_w) { /* wait time */ - o_wait = xatoi_u(str_w); - } + //if (option_mask32 & OPT_w) /* wait time */ //if (option_mask32 & OPT_z) /* little or no data xfer */ /* We manage our fd's so that they are never 0,1,2 */ @@ -751,34 +813,46 @@ int nc_main(int argc, char **argv) if (option_mask32 & OPT_s) { /* local address */ /* if o_lport is still 0, then we will use random port */ ouraddr = xhost2sockaddr(str_s, o_lport); +#ifdef BLOAT + /* prevent spurious "UDP listen needs !0 port" */ + o_lport = get_nport(ouraddr); + o_lport = ntohs(o_lport); +#endif x = xsocket(ouraddr->u.sa.sa_family, x, 0); } else { /* We try IPv6, then IPv4, unless addr family is * implicitly set by way of remote addr/port spec */ x = xsocket_type(&ouraddr, - USE_FEATURE_IPV6((themaddr ? themaddr->u.sa.sa_family : AF_UNSPEC),) + (themaddr ? themaddr->u.sa.sa_family : AF_UNSPEC), x); if (o_lport) - set_nport(ouraddr, htons(o_lport)); + set_nport(&ouraddr->u.sa, htons(o_lport)); } xmove_fd(x, netfd); setsockopt_reuseaddr(netfd); if (o_udpmode) socket_want_pktinfo(netfd); - xbind(netfd, &ouraddr->u.sa, ouraddr->len); + if (!ENABLE_FEATURE_UNIX_LOCAL + || o_listen + || ouraddr->u.sa.sa_family != AF_UNIX + ) { + xbind(netfd, &ouraddr->u.sa, ouraddr->len); + } #if 0 setsockopt(netfd, SOL_SOCKET, SO_RCVBUF, &o_rcvbuf, sizeof o_rcvbuf); setsockopt(netfd, SOL_SOCKET, SO_SNDBUF, &o_sndbuf, sizeof o_sndbuf); #endif +#ifdef BLOAT if (OPT_l && (option_mask32 & (OPT_u|OPT_l)) == (OPT_u|OPT_l)) { /* apparently UDP can listen ON "port 0", but that's not useful */ if (!o_lport) bb_error_msg_and_die("UDP listen needs nonzero -p port"); } +#endif - FD_SET(0, &ding1); /* stdin *is* initially open */ + FD_SET(STDIN_FILENO, &ding1); /* stdin *is* initially open */ if (proggie) { close(0); /* won't need stdin */ option_mask32 &= ~OPT_o; /* -o with -e is meaningless! */ @@ -797,7 +871,7 @@ int nc_main(int argc, char **argv) } else { /* Outbound connects. Now we're more picky about args... */ if (!themaddr) - bb_error_msg_and_die("no destination"); + bb_show_usage(); remend = *themaddr; if (o_verbose)