X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=networking%2Fnc_bloaty.c;h=64098648aae6a86abcddc970aae788bba8c6c389;hb=46ba2468a3de85076ce92ce8e8cc7a086bac69f0;hp=3c622e51ecddbf208e2659949b06d23b3bf19993;hpb=1e23f32453d8aa84c66c8f0bb9f753d68614d05a;p=oweals%2Fbusybox.git diff --git a/networking/nc_bloaty.c b/networking/nc_bloaty.c index 3c622e51e..64098648a 100644 --- a/networking/nc_bloaty.c +++ b/networking/nc_bloaty.c @@ -48,6 +48,12 @@ * - 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 we don't exit - we continue to listen/accept. + * Since bbox 1.22: + * - nc exits when _both_ stdin and network are closed. + * This makes these two commands: + * echo "Yes" | nc 127.0.0.1 1234 + * echo "no" | nc -lp 1234 + * exchange their data _and exit_ instead of being stuck. */ /* done in nc.c: #include "libbb.h" */ @@ -60,10 +66,15 @@ //usage: "nc [OPTIONS] -l -p PORT [HOST] [PORT] - listen" //usage: ) //usage:#define nc_full_usage "\n\n" -//usage: "Options:" -//usage: "\n -e PROG Run PROG after connect (must be last)" +//usage: " -e PROG Run PROG after connect (must be last)" //usage: IF_NC_SERVER( //usage: "\n -l Listen mode, for inbound connects" +//usage: "\n -lk With -e, provides persistent server" +/* -ll does the same as -lk, but its our extension, while -k is BSD'd, + * presumably more widely known. Therefore we advertise it, not -ll. + * I would like to drop -ll support, but our "small" nc supports it, + * and Rob uses it. + */ //usage: ) //usage: "\n -p PORT Local port" //usage: "\n -s ADDR Local address" @@ -116,6 +127,7 @@ 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) @@ -128,9 +140,6 @@ 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 */ char bigbuf_net[BIGSIZ]; }; @@ -142,8 +151,6 @@ struct globals { #define themaddr (G.themaddr ) #define remend (G.remend ) #define jbuf (G.jbuf ) -#define ding1 (G.ding1 ) -#define ding2 (G.ding2 ) #define bigbuf_in (G.bigbuf_in ) #define bigbuf_net (G.bigbuf_net) #define o_verbose (G.o_verbose ) @@ -160,26 +167,21 @@ 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_k = (1 << 7) * ENABLE_NC_SERVER, + OPT_i = (1 << (6+2*ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, + OPT_o = (1 << (7+2*ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, + OPT_z = (1 << (8+2*ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, }; #define o_nflag (option_mask32 & OPT_n) #define o_udpmode (option_mask32 & OPT_u) -#if ENABLE_NC_SERVER -#define o_listen (option_mask32 & OPT_l) -#else -#define o_listen 0 -#endif #if ENABLE_NC_EXTRA #define o_ofile (option_mask32 & OPT_o) #define o_zero (option_mask32 & OPT_z) @@ -264,12 +266,13 @@ Debug("findline returning whole thing: %d", siz); 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("can't execute '%s'", proggie[0]); + BB_EXECVP_or_die(proggie); } /* connect_w_timeout: @@ -299,7 +302,7 @@ static int connect_w_timeout(int fd) incoming and returns an open connection *from* someplace. If we were given host/port args, any connections from elsewhere are rejected. This in conjunction with local-address binding should limit things nicely... */ -static void dolisten(void) +static void dolisten(int is_persistent, char **proggie) { int rr; @@ -372,6 +375,7 @@ create new one, and bind() it. TODO */ xconnect(netfd, &remend.u.sa, ouraddr->len); } else { /* TCP */ + another: arm(o_wait); /* wrap this in a timer, too; 0 = forever */ if (setjmp(jbuf) == 0) { again: @@ -387,10 +391,10 @@ create new one, and bind() it. TODO */ if (port == 0) { /* "nc -nl -p LPORT RHOST" (w/o RPORT!): * we should accept any remote port */ - set_nport(&remend, 0); /* blot out 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, sv_port); /* restore */ + 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 */ @@ -406,6 +410,19 @@ create new one, and bind() it. TODO */ unarm(); } else bb_error_msg_and_die("timeout"); + + if (is_persistent && proggie) { + /* -l -k -e PROG */ + signal(SIGCHLD, SIG_IGN); /* no zombies please */ + if (xvfork() != 0) { + /* parent: go back and accept more connections */ + close(rr); + goto another; + } + /* child */ + signal(SIGCHLD, SIG_DFL); + } + xmove_fd(rr, netfd); /* dump the old socket, here's our new one */ /* find out what address the connection was *to* on our end, in case we're doing a listen-on-any on a multihomed machine. This allows one to @@ -430,8 +447,7 @@ create new one, and bind() it. TODO */ rr = getsockopt(netfd, IPPROTO_IP, IP_OPTIONS, optbuf, &x); if (rr >= 0 && x) { /* we've got options, lessee em... */ - bin2hex(bigbuf_net, optbuf, x); - bigbuf_net[2*x] = '\0'; + *bin2hex(bigbuf_net, optbuf, x) = '\0'; fprintf(stderr, "IP options: %s\n", bigbuf_net); } #endif @@ -443,7 +459,7 @@ create new one, and bind() it. TODO */ so I don't feel bad. The *real* question is why BFD sockets wasn't designed to allow listens for connections *from* specific hosts/ports, instead of requiring the caller to - accept the connection and then reject undesireable ones by closing. + accept the connection and then reject undesirable ones by closing. In other words, we need a TCP MSG_PEEK. */ /* bbox: removed most of it */ lcladdr = xmalloc_sockaddr2dotted(&ouraddr->u.sa); @@ -456,6 +472,9 @@ create new one, and bind() it. TODO */ if (!o_nflag) free(remhostname); } + + if (proggie) + doexec(proggie); } /* udptest: @@ -483,11 +502,11 @@ static int udptest(void) /* use the tcp-ping trick: try connecting to a normally refused port, which causes us to block for the time that SYN gets there and RST gets back. Not completely reliable, but it *does* mostly work. */ - /* Set a temporary connect timeout, so packet filtration doesnt cause + /* Set a temporary connect timeout, so packet filtration doesn't cause 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); @@ -563,76 +582,72 @@ void oprint(int direction, unsigned char *p, unsigned bc); #endif /* readwrite: - handle stdin/stdout/network I/O. Bwahaha!! -- the select loop from hell. + handle stdin/stdout/network I/O. Bwahaha!! -- the i/o loop from hell. In this instance, return what might become our exit status. */ static int readwrite(void) { - int rr; char *zp = zp; /* gcc */ /* stdin buf ptr */ char *np = np; /* net-in buf ptr */ unsigned rzleft; unsigned rnleft; unsigned netretry; /* net-read retry counter */ - unsigned wretry; /* net-write sanity counter */ - unsigned wfirst; /* one-shot flag to skip first net read */ + unsigned fds_open; - /* if you don't have all this FD_* macro hair in sys/types.h, you'll have to - either find it or do your own bit-bashing: *ding1 |= (1 << fd), etc... */ - FD_SET(netfd, &ding1); /* global: the net is open */ + struct pollfd pfds[2]; + pfds[0].fd = STDIN_FILENO; + pfds[0].events = POLLIN; + pfds[1].fd = netfd; + pfds[1].events = POLLIN; + + fds_open = 2; netretry = 2; - wfirst = 0; rzleft = rnleft = 0; if (o_interval) sleep(o_interval); /* pause *before* sending stuff, too */ - errno = 0; /* clear from sleep, close, whatever */ - /* and now the big ol' select shoveling loop ... */ - while (FD_ISSET(netfd, &ding1)) { /* i.e. till the *net* closes! */ - wretry = 8200; /* more than we'll ever hafta write */ - if (wfirst) { /* any saved stdin buffer? */ - wfirst = 0; /* clear flag for the duration */ - goto shovel; /* and go handle it first */ - } - ding2 = ding1; /* FD_COPY ain't portable... */ - /* some systems, notably linux, crap into their select timers on return, so - we create a expendable copy and give *that* to select. */ + /* and now the big ol' shoveling loop ... */ + /* nc 1.10 has "while (FD_ISSET(netfd)" here */ + while (fds_open) { + int rr; + int poll_tmout_ms; + unsigned wretry = 8200; /* net-write sanity counter */ + + poll_tmout_ms = -1; if (o_wait) { - struct timeval tmp_timer; - tmp_timer.tv_sec = o_wait; - tmp_timer.tv_usec = 0; - /* highest possible fd is netfd (3) */ - rr = select(netfd+1, &ding2, NULL, NULL, &tmp_timer); - } else - rr = select(netfd+1, &ding2, NULL, NULL, NULL); + poll_tmout_ms = INT_MAX; + if (o_wait < INT_MAX / 1000) + poll_tmout_ms = o_wait * 1000; + } + rr = poll(pfds, 2, poll_tmout_ms); if (rr < 0 && errno != EINTR) { /* might have gotten ^Zed, etc */ - holler_perror("select"); + holler_perror("poll"); close(netfd); return 1; } /* 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(STDIN_FILENO, &ding1)) + if (!pfds[0].revents) { netretry--; /* we actually try a coupla times. */ - if (!netretry) { - if (o_verbose > 1) /* normally we don't care */ - fprintf(stderr, "net timeout\n"); - close(netfd); - return 0; /* not an error! */ + if (!netretry) { + if (o_verbose > 1) /* normally we don't care */ + fprintf(stderr, "net timeout\n"); + /*close(netfd); - redundant, exit will do it */ + return 0; /* not an error! */ + } } - } /* select timeout */ - /* xxx: should we check the exception fds too? The read fds seem to give - us the right info, and none of the examples I found bothered. */ + } /* timeout */ /* Ding!! Something arrived, go check all the incoming hoppers, net first */ - if (FD_ISSET(netfd, &ding2)) { /* net: ding! */ + if (pfds[1].revents) { /* net: ding! */ rr = read(netfd, bigbuf_net, BIGSIZ); if (rr <= 0) { if (rr < 0 && o_verbose > 1) { /* nc 1.10 doesn't do this */ bb_perror_msg("net read"); } - FD_CLR(netfd, &ding1); /* net closed, we'll finish up... */ + pfds[1].fd = -1; /* don't poll for netfd anymore */ + fds_open--; rzleft = 0; /* can't write anymore: broken pipe */ } else { rnleft = rr; @@ -647,16 +662,17 @@ Debug("got %d from the net, errno %d", rr, errno); goto shovel; /* okay, suck more stdin */ - if (FD_ISSET(STDIN_FILENO, &ding2)) { /* stdin: ding! */ + if (pfds[0].revents) { /* 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(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?) + pfds[0].fd = -1; /* disable stdin */ + /*close(STDIN_FILENO); - not really necessary */ + /* Let peer know we have no more data */ + /* nc 1.10 doesn't do this: */ + shutdown(netfd, SHUT_WR); + fds_open--; } else { rzleft = rr; zp = bigbuf_in; @@ -667,24 +683,14 @@ Debug("got %d from the net, errno %d", rr, errno); Geez, why does this look an awful lot like the big loop in "rsh"? ... not sure if the order of this matters, but write net -> stdout first. */ - /* sanity check. Works because they're both unsigned... */ - if ((rzleft > 8200) || (rnleft > 8200)) { - holler_error("bogus buffers: %u, %u", rzleft, rnleft); - rzleft = rnleft = 0; - } - /* net write retries sometimes happen on UDP connections */ - if (!wretry) { /* is something hung? */ - holler_error("too many output retries"); - return 1; - } if (rnleft) { rr = write(STDOUT_FILENO, np, rnleft); if (rr > 0) { 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 */ + np += rr; + rnleft -= rr; + wrote_out += rr; /* global count */ } Debug("wrote %d to stdout, errno %d", rr, errno); } /* rnleft */ @@ -699,20 +705,24 @@ Debug("wrote %d to stdout, errno %d", rr, errno); oprint('>', (unsigned char *)zp, rr); zp += rr; rzleft -= rr; - wrote_net += rr; /* global count */ + wrote_net += rr; /* global count */ } Debug("wrote %d to net, errno %d", rr, errno); } /* rzleft */ if (o_interval) { /* cycle between slow lines, or ... */ sleep(o_interval); - errno = 0; /* clear from sleep */ - continue; /* ...with hairy select loop... */ + continue; /* ...with hairy loop... */ } - if ((rzleft) || (rnleft)) { /* shovel that shit till they ain't */ + if (rzleft || rnleft) { /* shovel that shit till they ain't */ wretry--; /* none left, and get another load */ + /* net write retries sometimes happen on UDP connections */ + if (!wretry) { /* is something hung? */ + holler_error("too many output retries"); + return 1; + } goto shovel; } - } /* while ding1:netfd is open */ + } /* while (fds_open) */ /* XXX: maybe want a more graceful shutdown() here, or screw around with linger times?? I suspect that I don't need to since I'm always doing @@ -729,9 +739,10 @@ int nc_main(int argc UNUSED_PARAM, char **argv) { char *str_p, *str_s; IF_NC_EXTRA(char *str_i, *str_o;) - char *themdotted = themdotted; /* gcc */ + char *themdotted = themdotted; /* for compiler */ char **proggie; int x; + unsigned cnt_l = 0; unsigned o_lport = 0; INIT_G(); @@ -757,22 +768,44 @@ int nc_main(int argc UNUSED_PARAM, char **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("lk")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:w+"; /* max 2 params; -v is a counter; -w N */ - getopt32(argv, "hnp: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); + getopt32(argv, "^" + "np:s:uvw:+"/* -w N */ IF_NC_SERVER("lk") + IF_NC_EXTRA("i:o:z") + "\0" + "?2:vv:ll", /* max 2 params; -v and -l are counters */ + &str_p, &str_s, &o_wait + IF_NC_EXTRA(, &str_i, &str_o) + , &o_verbose IF_NC_SERVER(, &cnt_l) + ); argv += optind; #if ENABLE_NC_EXTRA if (option_mask32 & OPT_i) /* line-interval time */ o_interval = xatou_range(str_i, 1, 0xffff); #endif +#if ENABLE_NC_SERVER //if (option_mask32 & OPT_l) /* listen mode */ + if (option_mask32 & OPT_k) /* persistent server mode */ + cnt_l = 2; +#endif //if (option_mask32 & OPT_n) /* numeric-only, no DNS lookups */ //if (option_mask32 & OPT_o) /* hexdump log */ if (option_mask32 & OPT_p) { /* local source port */ @@ -814,21 +847,21 @@ int nc_main(int argc UNUSED_PARAM, char **argv) (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); if (!ENABLE_FEATURE_UNIX_LOCAL - || o_listen + || cnt_l != 0 /* 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); + setsockopt_SOL_SOCKET_int(netfd, SO_RCVBUF, o_rcvbuf); + setsockopt_SOL_SOCKET_int(netfd, SO_SNDBUF, o_sndbuf); #endif #ifdef BLOAT @@ -840,9 +873,8 @@ int nc_main(int argc UNUSED_PARAM, char **argv) } #endif - FD_SET(STDIN_FILENO, &ding1); /* stdin *is* initially open */ if (proggie) { - close(0); /* won't need stdin */ + close(STDIN_FILENO); /* won't need stdin */ option_mask32 &= ~OPT_o; /* -o with -e is meaningless! */ } #if ENABLE_NC_EXTRA @@ -850,11 +882,9 @@ int nc_main(int argc UNUSED_PARAM, char **argv) xmove_fd(xopen(str_o, O_WRONLY|O_CREAT|O_TRUNC), ofd); #endif - if (o_listen) { - dolisten(); + if (cnt_l != 0) { + dolisten((cnt_l - 1), proggie); /* dolisten does its own connect reporting */ - if (proggie) /* -e given? */ - doexec(proggie); x = readwrite(); /* it even works with UDP! */ } else { /* Outbound connects. Now we're more picky about args... */