diff --git a/src/iodined.c b/src/iodined.c index 96d7188..e1f4b94 100644 --- a/src/iodined.c +++ b/src/iodined.c @@ -1172,43 +1172,50 @@ main(int argc, char **argv) my_ip = inet_addr(argv[0]); if (my_ip == INADDR_NONE) { - warnx("Bad IP address to use inside tunnel.\n"); + warnx("Bad IP address to use inside tunnel."); usage(); } topdomain = strdup(argv[1]); if(strlen(topdomain) <= 128) { if(check_topdomain(topdomain)) { - warnx("Topdomain contains invalid characters.\n"); + warnx("Topdomain contains invalid characters."); usage(); } } else { - warnx("Use a topdomain max 128 chars long.\n"); + warnx("Use a topdomain max 128 chars long."); usage(); } if (username != NULL) { #ifndef WINDOWS32 if ((pw = getpwnam(username)) == NULL) { - warnx("User %s does not exist!\n", username); + warnx("User %s does not exist!", username); usage(); } #endif } if (mtu <= 0) { - warnx("Bad MTU given.\n"); + warnx("Bad MTU given."); usage(); } if(port < 1 || port > 65535) { - warnx("Bad port number given.\n"); + warnx("Bad port number given."); usage(); } if(bind_enable) { - if (bind_port < 1 || bind_port > 65535 || bind_port == port) { - warnx("Bad DNS server port number given.\n"); + if (bind_port < 1 || bind_port > 65535) { + warnx("Bad DNS server port number given."); + usage(); + /* NOTREACHED */ + } + /* Avoid forwarding loops */ + if (bind_port == port && (listen_ip == INADDR_ANY || listen_ip == htonl(0x7f000001L))) { + warnx("Forward port is same as listen port (%d), will create a loop!", bind_port); + fprintf(stderr, "Use -l to set listen ip to avoid this.\n"); usage(); /* NOTREACHED */ } @@ -1228,16 +1235,16 @@ main(int argc, char **argv) } if (listen_ip == INADDR_NONE) { - warnx("Bad IP address to listen on.\n"); + warnx("Bad IP address to listen on."); usage(); } if (ns_ip == INADDR_NONE) { - warnx("Bad IP address to return as nameserver.\n"); + warnx("Bad IP address to return as nameserver."); usage(); } if (netmask > 30 || netmask < 8) { - warnx("Bad netmask (%d bits). Use 8-30 bits.\n", netmask); + warnx("Bad netmask (%d bits). Use 8-30 bits.", netmask); usage(); }