X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=networking%2Fnc_bloaty.c;h=64098648aae6a86abcddc970aae788bba8c6c389;hb=9a4100cf53f75356854ce752374babf8135c3f42;hp=00ba6f114657cf7660132fb670b4b53637e61aab;hpb=de6f14800675cd0401106876da81da7618de71c6;p=oweals%2Fbusybox.git diff --git a/networking/nc_bloaty.c b/networking/nc_bloaty.c index 00ba6f114..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" */ @@ -134,8 +140,6 @@ struct globals { jmp_buf jbuf; /* timer crud */ - fd_set ding1; /* for select loop */ - fd_set ding2; char bigbuf_in[BIGSIZ]; /* data buffers */ char bigbuf_net[BIGSIZ]; }; @@ -147,8 +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 ) @@ -173,9 +175,9 @@ enum { OPT_w = (1 << 5), OPT_l = (1 << 6) * ENABLE_NC_SERVER, OPT_k = (1 << 7) * ENABLE_NC_SERVER, - OPT_i = (1 << (7+2*ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, - OPT_o = (1 << (8+2*ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, - OPT_z = (1 << (9+2*ENABLE_NC_SERVER)) * ENABLE_NC_EXTRA, + 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) @@ -457,7 +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); @@ -500,7 +502,7 @@ 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); @@ -580,76 +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; + + struct pollfd pfds[2]; + pfds[0].fd = STDIN_FILENO; + pfds[0].events = POLLIN; + pfds[1].fd = netfd; + pfds[1].events = POLLIN; - /* 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 */ + 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; @@ -664,16 +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; @@ -684,24 +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 */ @@ -716,20 +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 @@ -794,11 +787,15 @@ int nc_main(int argc UNUSED_PARAM, char **argv) e_found: // -g -G -t -r deleted, unimplemented -a deleted too - opt_complementary = "?2:vv:ll:w+"; /* max 2 params; -v and -l are counters; -w N */ - getopt32(argv, "np:s:uvw:" IF_NC_SERVER("lk") - IF_NC_EXTRA("i:o:z"), - &str_p, &str_s, &o_wait - IF_NC_EXTRA(, &str_i, &str_o), &o_verbose IF_NC_SERVER(, &cnt_l)); + 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 */ @@ -863,8 +860,8 @@ int nc_main(int argc UNUSED_PARAM, char **argv) 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 @@ -876,9 +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