diff options
Diffstat (limited to 'ipsvd')
| -rw-r--r-- | ipsvd/Config.in | 20 | ||||
| -rw-r--r-- | ipsvd/Kbuild | 9 | ||||
| -rw-r--r-- | ipsvd/ipsvd_perhost.c | 65 | ||||
| -rw-r--r-- | ipsvd/ipsvd_perhost.h | 29 | ||||
| -rw-r--r-- | ipsvd/tcpudp.c | 608 |
5 files changed, 0 insertions, 731 deletions
diff --git a/ipsvd/Config.in b/ipsvd/Config.in deleted file mode 100644 index 0cb8c62..0000000 --- a/ipsvd/Config.in +++ /dev/null @@ -1,20 +0,0 @@ -# -# For a description of the syntax of this configuration file, -# see scripts/kbuild/config-language.txt. -# - -menu "ipsvd Utilities" - -config TCPSVD - bool "tcpsvd" - default n - help - tcpsvd listens on a tcp port and runs a program for each new connection - -config UDPSVD - bool "udpsvd" - default n - help - udpsvd listens on a udp port and runs a program for each new connection - -endmenu diff --git a/ipsvd/Kbuild b/ipsvd/Kbuild deleted file mode 100644 index fc34fea..0000000 --- a/ipsvd/Kbuild +++ /dev/null @@ -1,9 +0,0 @@ -# Makefile for busybox -# -# Copyright (C) 1999-2005 by Erik Andersen <andersen@codepoet.org> -# -# Licensed under the GPL v2, see the file LICENSE in this tarball. - -lib-y:= -lib-$(CONFIG_TCPSVD) += tcpudp.o ipsvd_perhost.o -lib-$(CONFIG_UDPSVD) += tcpudp.o ipsvd_perhost.o diff --git a/ipsvd/ipsvd_perhost.c b/ipsvd/ipsvd_perhost.c deleted file mode 100644 index 6075c0a..0000000 --- a/ipsvd/ipsvd_perhost.c +++ /dev/null @@ -1,65 +0,0 @@ -/* Based on ipsvd utilities written by Gerrit Pape <pape@smarden.org> - * which are released into public domain by the author. - * Homepage: http://smarden.sunsite.dk/ipsvd/ - * - * Copyright (C) 2007 Denys Vlasenko. - * - * Licensed under GPLv2, see file LICENSE in this tarball for details. - */ - -#include "libbb.h" -#include "ipsvd_perhost.h" - -static struct hcc *cc; -static unsigned cclen; - -/* to be optimized */ - -void ipsvd_perhost_init(unsigned c) -{ -// free(cc); - cc = xzalloc(c * sizeof(*cc)); - cclen = c; -} - -unsigned ipsvd_perhost_add(char *ip, unsigned maxconn, struct hcc **hccpp) -{ - unsigned i; - unsigned conn = 1; - int freepos = -1; - - for (i = 0; i < cclen; ++i) { - if (!cc[i].ip) { - freepos = i; - continue; - } - if (strcmp(cc[i].ip, ip) == 0) { - conn++; - continue; - } - } - if (freepos == -1) return 0; - if (conn <= maxconn) { - cc[freepos].ip = ip; - *hccpp = &cc[freepos]; - } - return conn; -} - -void ipsvd_perhost_remove(int pid) -{ - unsigned i; - for (i = 0; i < cclen; ++i) { - if (cc[i].pid == pid) { - free(cc[i].ip); - cc[i].ip = NULL; - cc[i].pid = 0; - return; - } - } -} - -//void ipsvd_perhost_free(void) -//{ -// free(cc); -//} diff --git a/ipsvd/ipsvd_perhost.h b/ipsvd/ipsvd_perhost.h deleted file mode 100644 index 9fc8cee..0000000 --- a/ipsvd/ipsvd_perhost.h +++ /dev/null @@ -1,29 +0,0 @@ -/* Based on ipsvd utilities written by Gerrit Pape <pape@smarden.org> - * which are released into public domain by the author. - * Homepage: http://smarden.sunsite.dk/ipsvd/ - * - * Copyright (C) 2007 Denys Vlasenko. - * - * Licensed under GPLv2, see file LICENSE in this tarball for details. - */ - -struct hcc { - char *ip; - int pid; -}; - -void ipsvd_perhost_init(unsigned); - -/* Returns number of already opened connects to this ips, including this one. - * ip should be a malloc'ed ptr. - * If return value is <= maxconn, ip is inserted into the table - * and pointer to table entry if stored in *hccpp - * (useful for storing pid later). - * Else ip is NOT inserted (you must take care of it - free() etc) */ -unsigned ipsvd_perhost_add(char *ip, unsigned maxconn, struct hcc **hccpp); - -/* Finds and frees element with pid */ -void ipsvd_perhost_remove(int pid); - -//unsigned ipsvd_perhost_setpid(int pid); -//void ipsvd_perhost_free(void); diff --git a/ipsvd/tcpudp.c b/ipsvd/tcpudp.c deleted file mode 100644 index 729b7bc..0000000 --- a/ipsvd/tcpudp.c +++ /dev/null @@ -1,608 +0,0 @@ -/* Based on ipsvd utilities written by Gerrit Pape <pape@smarden.org> - * which are released into public domain by the author. - * Homepage: http://smarden.sunsite.dk/ipsvd/ - * - * Copyright (C) 2007 Denys Vlasenko. - * - * Licensed under GPLv2, see file LICENSE in this tarball for details. - */ - -/* Based on ipsvd ipsvd-0.12.1. This tcpsvd accepts all options - * which are supported by one from ipsvd-0.12.1, but not all are - * functional. See help text at the end of this file for details. - * - * Code inside "#ifdef SSLSVD" is for sslsvd and is currently unused. - * - * Busybox version exports TCPLOCALADDR instead of - * TCPLOCALIP + TCPLOCALPORT pair. ADDR more closely matches reality - * (which is "struct sockaddr_XXX". Port is not a separate entity, - * it's just a part of (AF_INET[6]) sockaddr!). - * - * TCPORIGDSTADDR is Busybox-specific addition. - * - * udp server is hacked up by reusing TCP code. It has the following - * limitation inherent in Unix DGRAM sockets implementation: - * - local IP address is retrieved (using recvmsg voodoo) but - * child's socket is not bound to it (bind cannot be called on - * already bound socket). Thus it still can emit outgoing packets - * with wrong source IP... - * - don't know how to retrieve ORIGDST for udp. - */ - -#include <limits.h> -#include <linux/netfilter_ipv4.h> /* wants <limits.h> */ - -#include "libbb.h" -#include "ipsvd_perhost.h" - -#ifdef SSLSVD -#include "matrixSsl.h" -#include "ssl_io.h" -#endif - -struct globals { - unsigned verbose; - unsigned max_per_host; - unsigned cur_per_host; - unsigned cnum; - unsigned cmax; - char **env_cur; - char *env_var[1]; /* actually bigger */ -}; -#define G (*(struct globals*)&bb_common_bufsiz1) -#define verbose (G.verbose ) -#define max_per_host (G.max_per_host) -#define cur_per_host (G.cur_per_host) -#define cnum (G.cnum ) -#define cmax (G.cmax ) -#define env_cur (G.env_cur ) -#define env_var (G.env_var ) -#define INIT_G() \ - do { \ - cmax = 30; \ - env_cur = &env_var[0]; \ - } while (0) - - -/* We have to be careful about leaking memory in repeated setenv's */ -static void xsetenv_plain(const char *n, const char *v) -{ - char *var = xasprintf("%s=%s", n, v); - *env_cur++ = var; - putenv(var); -} - -static void xsetenv_proto(const char *proto, const char *n, const char *v) -{ - char *var = xasprintf("%s%s=%s", proto, n, v); - *env_cur++ = var; - putenv(var); -} - -static void undo_xsetenv(void) -{ - char **pp = env_cur = &env_var[0]; - while (*pp) { - char *var = *pp; - *strchrnul(var, '=') = '\0'; - unsetenv(var); - free(var); - *pp++ = NULL; - } -} - -static void sig_term_handler(int sig) -{ - if (verbose) - bb_error_msg("got signal %u, exit", sig); - kill_myself_with_sig(sig); -} - -/* Little bloated, but tries to give accurate info how child exited. - * Makes easier to spot segfaulting children etc... */ -static void print_waitstat(unsigned pid, int wstat) -{ - unsigned e = 0; - const char *cause = "?exit"; - - if (WIFEXITED(wstat)) { - cause++; - e = WEXITSTATUS(wstat); - } else if (WIFSIGNALED(wstat)) { - cause = "signal"; - e = WTERMSIG(wstat); - } - bb_error_msg("end %d %s %d", pid, cause, e); -} - -/* Must match getopt32 in main! */ -enum { - OPT_c = (1 << 0), - OPT_C = (1 << 1), - OPT_i = (1 << 2), - OPT_x = (1 << 3), - OPT_u = (1 << 4), - OPT_l = (1 << 5), - OPT_E = (1 << 6), - OPT_b = (1 << 7), - OPT_h = (1 << 8), - OPT_p = (1 << 9), - OPT_t = (1 << 10), - OPT_v = (1 << 11), - OPT_V = (1 << 12), - OPT_U = (1 << 13), /* from here: sslsvd only */ - OPT_slash = (1 << 14), - OPT_Z = (1 << 15), - OPT_K = (1 << 16), -}; - -static void connection_status(void) -{ - /* "only 1 client max" desn't need this */ - if (cmax > 1) - bb_error_msg("status %u/%u", cnum, cmax); -} - -static void sig_child_handler(int sig ATTRIBUTE_UNUSED) -{ - int wstat; - int pid; - - while ((pid = wait_any_nohang(&wstat)) > 0) { - if (max_per_host) - ipsvd_perhost_remove(pid); - if (cnum) - cnum--; - if (verbose) - print_waitstat(pid, wstat); - } - if (verbose) - connection_status(); -} - -int tcpudpsvd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; -int tcpudpsvd_main(int argc ATTRIBUTE_UNUSED, char **argv) -{ - char *str_C, *str_t; - char *user; - struct hcc *hccp; - const char *instructs; - char *msg_per_host = NULL; - unsigned len_per_host = len_per_host; /* gcc */ -#ifndef SSLSVD - struct bb_uidgid_t ugid; -#endif - bool tcp; - uint16_t local_port; - char *preset_local_hostname = NULL; - char *remote_hostname = remote_hostname; /* for compiler */ - char *remote_addr = remote_addr; /* for compiler */ - len_and_sockaddr *lsa; - len_and_sockaddr local, remote; - socklen_t sa_len; - int pid; - int sock; - int conn; - unsigned backlog = 20; - - INIT_G(); - - tcp = (applet_name[0] == 't'); - - /* 3+ args, -i at most once, -p implies -h, -v is counter, -b N, -c N */ - opt_complementary = "-3:i--i:ph:vv:b+:c+"; -#ifdef SSLSVD - getopt32(argv, "+c:C:i:x:u:l:Eb:hpt:vU:/:Z:K:", - &cmax, &str_C, &instructs, &instructs, &user, &preset_local_hostname, - &backlog, &str_t, &ssluser, &root, &cert, &key, &verbose - ); -#else - /* "+": stop on first non-option */ - getopt32(argv, "+c:C:i:x:u:l:Eb:hpt:v", - &cmax, &str_C, &instructs, &instructs, &user, &preset_local_hostname, - &backlog, &str_t, &verbose - ); -#endif - if (option_mask32 & OPT_C) { /* -C n[:message] */ - max_per_host = bb_strtou(str_C, &str_C, 10); - if (str_C[0]) { - if (str_C[0] != ':') - bb_show_usage(); - msg_per_host = str_C + 1; - len_per_host = strlen(msg_per_host); - } - } - if (max_per_host > cmax) - max_per_host = cmax; - if (option_mask32 & OPT_u) { - if (!get_uidgid(&ugid, user, 1)) - bb_error_msg_and_die("unknown user/group: %s", user); - } -#ifdef SSLSVD - if (option_mask32 & OPT_U) ssluser = optarg; - if (option_mask32 & OPT_slash) root = optarg; - if (option_mask32 & OPT_Z) cert = optarg; - if (option_mask32 & OPT_K) key = optarg; -#endif - argv += optind; - if (!argv[0][0] || LONE_CHAR(argv[0], '0')) - argv[0] = (char*)"0.0.0.0"; - - /* Per-IP flood protection is not thought-out for UDP */ - if (!tcp) - max_per_host = 0; - - bb_sanitize_stdio(); /* fd# 0,1,2 must be opened */ - -#ifdef SSLSVD - sslser = user; - client = 0; - if ((getuid() == 0) && !(option_mask32 & OPT_u)) { - xfunc_exitcode = 100; - bb_error_msg_and_die("-U ssluser must be set when running as root"); - } - if (option_mask32 & OPT_u) - if (!uidgid_get(&sslugid, ssluser, 1)) { - if (errno) { - bb_perror_msg_and_die("fatal: cannot get user/group: %s", ssluser); - } - bb_error_msg_and_die("unknown user/group '%s'", ssluser); - } - if (!cert) cert = "./cert.pem"; - if (!key) key = cert; - if (matrixSslOpen() < 0) - fatal("cannot initialize ssl"); - if (matrixSslReadKeys(&keys, cert, key, 0, ca) < 0) { - if (client) - fatal("cannot read cert, key, or ca file"); - fatal("cannot read cert or key file"); - } - if (matrixSslNewSession(&ssl, keys, 0, SSL_FLAGS_SERVER) < 0) - fatal("cannot create ssl session"); -#endif - - sig_block(SIGCHLD); - signal(SIGCHLD, sig_child_handler); - bb_signals(BB_SIGS_FATAL, sig_term_handler); - signal(SIGPIPE, SIG_IGN); - - if (max_per_host) - ipsvd_perhost_init(cmax); - - local_port = bb_lookup_port(argv[1], tcp ? "tcp" : "udp", 0); - lsa = xhost2sockaddr(argv[0], local_port); - argv += 2; - - sock = xsocket(lsa->u.sa.sa_family, tcp ? SOCK_STREAM : SOCK_DGRAM, 0); - setsockopt_reuseaddr(sock); - sa_len = lsa->len; /* I presume sockaddr len stays the same */ - xbind(sock, &lsa->u.sa, sa_len); - if (tcp) - xlisten(sock, backlog); - else /* udp: needed for recv_from_to to work: */ - socket_want_pktinfo(sock); - /* ndelay_off(sock); - it is the default I think? */ - -#ifndef SSLSVD - if (option_mask32 & OPT_u) { - /* drop permissions */ - xsetgid(ugid.gid); - xsetuid(ugid.uid); - } -#endif - - if (verbose) { - char *addr = xmalloc_sockaddr2dotted(&lsa->u.sa); - bb_error_msg("listening on %s, starting", addr); - free(addr); -#ifndef SSLSVD - if (option_mask32 & OPT_u) - printf(", uid %u, gid %u", - (unsigned)ugid.uid, (unsigned)ugid.gid); -#endif - } - - /* Main accept() loop */ - - again: - hccp = NULL; - - while (cnum >= cmax) - wait_for_any_sig(); /* expecting SIGCHLD */ - - /* Accept a connection to fd #0 */ - again1: - close(0); - again2: - sig_unblock(SIGCHLD); - local.len = remote.len = sa_len; - if (tcp) { - conn = accept(sock, &remote.u.sa, &remote.len); - } else { - /* In case recv_from_to won't be able to recover local addr. - * Also sets port - recv_from_to is unable to do it. */ - local = *lsa; - conn = recv_from_to(sock, NULL, 0, MSG_PEEK, - &remote.u.sa, &local.u.sa, sa_len); - } - sig_block(SIGCHLD); - if (conn < 0) { - if (errno != EINTR) - bb_perror_msg(tcp ? "accept" : "recv"); - goto again2; - } - xmove_fd(tcp ? conn : sock, 0); - - if (max_per_host) { - /* Drop connection immediately if cur_per_host > max_per_host - * (minimizing load under SYN flood) */ - remote_addr = xmalloc_sockaddr2dotted_noport(&remote.u.sa); - cur_per_host = ipsvd_perhost_add(remote_addr, max_per_host, &hccp); - if (cur_per_host > max_per_host) { - /* ipsvd_perhost_add detected that max is exceeded - * (and did not store ip in connection table) */ - free(remote_addr); - if (msg_per_host) { - /* don't block or test for errors */ - send(0, msg_per_host, len_per_host, MSG_DONTWAIT); - } - goto again1; - } - /* NB: remote_addr is not leaked, it is stored in conn table */ - } - - if (!tcp) { - /* Voodoo magic: making udp sockets each receive its own - * packets is not trivial, and I still not sure - * I do it 100% right. - * 1) we have to do it before fork() - * 2) order is important - is it right now? */ - - /* Open new non-connected UDP socket for further clients... */ - sock = xsocket(lsa->u.sa.sa_family, SOCK_DGRAM, 0); - setsockopt_reuseaddr(sock); - /* Make plain write/send work for old socket by supplying default - * destination address. This also restricts incoming packets - * to ones coming from this remote IP. */ - xconnect(0, &remote.u.sa, sa_len); - /* hole? at this point we have no wildcard udp socket... - * can this cause clients to get "port unreachable" icmp? - * Yup, time window is very small, but it exists (is it?) */ - /* ..."open new socket", continued */ - xbind(sock, &lsa->u.sa, sa_len); - socket_want_pktinfo(sock); - - /* Doesn't work: - * we cannot replace fd #0 - we will lose pending packet - * which is already buffered for us! And we cannot use fd #1 - * instead - it will "intercept" all following packets, but child - * does not expect data coming *from fd #1*! */ -#if 0 - /* Make it so that local addr is fixed to localp->u.sa - * and we don't accidentally accept packets to other local IPs. */ - /* NB: we possibly bind to the _very_ same_ address & port as the one - * already bound in parent! This seems to work in Linux. - * (otherwise we can move socket to fd #0 only if bind succeeds) */ - close(0); - set_nport(localp, htons(local_port)); - xmove_fd(xsocket(localp->u.sa.sa_family, SOCK_DGRAM, 0), 0); - setsockopt_reuseaddr(0); /* crucial */ - xbind(0, &localp->u.sa, localp->len); -#endif - } - - pid = vfork(); - if (pid == -1) { - bb_perror_msg("vfork"); - goto again; - } - - if (pid != 0) { - /* Parent */ - cnum++; - if (verbose) - connection_status(); - if (hccp) - hccp->pid = pid; - /* clean up changes done by vforked child */ - undo_xsetenv(); - goto again; - } - - /* Child: prepare env, log, and exec prog */ - - /* Closing tcp listening socket */ - if (tcp) - close(sock); - - { /* vfork alert! every xmalloc in this block should be freed! */ - char *local_hostname = local_hostname; /* for compiler */ - char *local_addr = NULL; - char *free_me0 = NULL; - char *free_me1 = NULL; - char *free_me2 = NULL; - - if (verbose || !(option_mask32 & OPT_E)) { - if (!max_per_host) /* remote_addr is not yet known */ - free_me0 = remote_addr = xmalloc_sockaddr2dotted(&remote.u.sa); - if (option_mask32 & OPT_h) { - free_me1 = remote_hostname = xmalloc_sockaddr2host_noport(&remote.u.sa); - if (!remote_hostname) { - bb_error_msg("cannot look up hostname for %s", remote_addr); - remote_hostname = remote_addr; - } - } - /* Find out local IP peer connected to. - * Errors ignored (I'm not paranoid enough to imagine kernel - * which doesn't know local IP). */ - if (tcp) - getsockname(0, &local.u.sa, &local.len); - /* else: for UDP it is done earlier by parent */ - local_addr = xmalloc_sockaddr2dotted(&local.u.sa); - if (option_mask32 & OPT_h) { - local_hostname = preset_local_hostname; - if (!local_hostname) { - free_me2 = local_hostname = xmalloc_sockaddr2host_noport(&local.u.sa); - if (!local_hostname) - bb_error_msg_and_die("cannot look up hostname for %s", local_addr); - } - /* else: local_hostname is not NULL, but is NOT malloced! */ - } - } - if (verbose) { - pid = getpid(); - if (max_per_host) { - bb_error_msg("concurrency %s %u/%u", - remote_addr, - cur_per_host, max_per_host); - } - bb_error_msg((option_mask32 & OPT_h) - ? "start %u %s-%s (%s-%s)" - : "start %u %s-%s", - pid, - local_addr, remote_addr, - local_hostname, remote_hostname); - } - - if (!(option_mask32 & OPT_E)) { - /* setup ucspi env */ - const char *proto = tcp ? "TCP" : "UDP"; - - /* Extract "original" destination addr:port - * from Linux firewall. Useful when you redirect - * an outbond connection to local handler, and it needs - * to know where it originally tried to connect */ - if (tcp && getsockopt(0, SOL_IP, SO_ORIGINAL_DST, &local.u.sa, &local.len) == 0) { - char *addr = xmalloc_sockaddr2dotted(&local.u.sa); - xsetenv_plain("TCPORIGDSTADDR", addr); - free(addr); - } - xsetenv_plain("PROTO", proto); - xsetenv_proto(proto, "LOCALADDR", local_addr); - xsetenv_proto(proto, "REMOTEADDR", remote_addr); - if (option_mask32 & OPT_h) { - xsetenv_proto(proto, "LOCALHOST", local_hostname); - xsetenv_proto(proto, "REMOTEHOST", remote_hostname); - } - //compat? xsetenv_proto(proto, "REMOTEINFO", ""); - /* additional */ - if (cur_per_host > 0) /* can not be true for udp */ - xsetenv_plain("TCPCONCURRENCY", utoa(cur_per_host)); - } - free(local_addr); - free(free_me0); - free(free_me1); - free(free_me2); - } - - xdup2(0, 1); - - signal(SIGTERM, SIG_DFL); - signal(SIGPIPE, SIG_DFL); - signal(SIGCHLD, SIG_DFL); - sig_unblock(SIGCHLD); - -#ifdef SSLSVD - strcpy(id, utoa(pid)); - ssl_io(0, argv); -#else - BB_EXECVP(argv[0], argv); -#endif - bb_perror_msg_and_die("exec '%s'", argv[0]); -} - -/* -tcpsvd [-hpEvv] [-c n] [-C n:msg] [-b n] [-u user] [-l name] - [-i dir|-x cdb] [ -t sec] host port prog - -tcpsvd creates a TCP/IP socket, binds it to the address host:port, -and listens on the socket for incoming connections. - -On each incoming connection, tcpsvd conditionally runs a program, -with standard input reading from the socket, and standard output -writing to the socket, to handle this connection. tcpsvd keeps -listening on the socket for new connections, and can handle -multiple connections simultaneously. - -tcpsvd optionally checks for special instructions depending -on the IP address or hostname of the client that initiated -the connection, see ipsvd-instruct(5). - -host - host either is a hostname, or a dotted-decimal IP address, - or 0. If host is 0, tcpsvd accepts connections to any local - IP address. - * busybox accepts IPv6 addresses and host:port pairs too - In this case second parameter is ignored -port - tcpsvd accepts connections to host:port. port may be a name - from /etc/services or a number. -prog - prog consists of one or more arguments. For each connection, - tcpsvd normally runs prog, with file descriptor 0 reading from - the network, and file descriptor 1 writing to the network. - By default it also sets up TCP-related environment variables, - see tcp-environ(5) --i dir - read instructions for handling new connections from the instructions - directory dir. See ipsvd-instruct(5) for details. - * ignored by busyboxed version --x cdb - read instructions for handling new connections from the constant database - cdb. The constant database normally is created from an instructions - directory by running ipsvd-cdb(8). - * ignored by busyboxed version --t sec - timeout. This option only takes effect if the -i option is given. - While checking the instructions directory, check the time of last access - of the file that matches the clients address or hostname if any, discard - and remove the file if it wasn't accessed within the last sec seconds; - tcpsvd does not discard or remove a file if the user's write permission - is not set, for those files the timeout is disabled. Default is 0, - which means that the timeout is disabled. - * ignored by busyboxed version --l name - local hostname. Do not look up the local hostname in DNS, but use name - as hostname. This option must be set if tcpsvd listens on port 53 - to avoid loops. --u user[:group] - drop permissions. Switch user ID to user's UID, and group ID to user's - primary GID after creating and binding to the socket. If user is followed - by a colon and a group name, the group ID is switched to the GID of group - instead. All supplementary groups are removed. --c n - concurrency. Handle up to n connections simultaneously. Default is 30. - If there are n connections active, tcpsvd defers acceptance of a new - connection until an active connection is closed. --C n[:msg] - per host concurrency. Allow only up to n connections from the same IP - address simultaneously. If there are n active connections from one IP - address, new incoming connections from this IP address are closed - immediately. If n is followed by :msg, the message msg is written - to the client if possible, before closing the connection. By default - msg is empty. See ipsvd-instruct(5) for supported escape sequences in msg. - - For each accepted connection, the current per host concurrency is - available through the environment variable TCPCONCURRENCY. n and msg - can be overwritten by ipsvd(7) instructions, see ipsvd-instruct(5). - By default tcpsvd doesn't keep track of connections. --h - Look up the client's hostname in DNS. --p - paranoid. After looking up the client's hostname in DNS, look up the IP - addresses in DNS for that hostname, and forget about the hostname - if none of the addresses match the client's IP address. You should - set this option if you use hostname based instructions. The -p option - implies the -h option. - * ignored by busyboxed version --b n - backlog. Allow a backlog of approximately n TCP SYNs. On some systems n - is silently limited. Default is 20. --E - no special environment. Do not set up TCP-related environment variables. --v - verbose. Print verbose messsages to standard output. --vv - more verbose. Print more verbose messages to standard output. - * no difference between -v and -vv in busyboxed version -*/ |