This is a patch against pl17 to optionally replace the simple behavior of using the synchronous gethostbyaddr() by creating the option to use an asynchronous resolver; the GNU adns library -- presumably if you apply this, you know what it does. ( Info on the adns library is at http://www.gnu.org/software/adns/ ) That library has to be installed on the system for it to work. and... in Makefile and Makefile.in: MYFLAGS = -Wall made to read: MYFLAGS = -Wall -DHAVE_ADNS and LIBS = -lcrypt made to read: LIBS = -lcryt -ladns -Mysidia diff --unified=3 ../src-orig/comm.c ./comm.c --- ../src-orig/comm.c Sat Apr 1 21:34:22 2000 +++ ./comm.c Wed Jun 28 16:59:41 2000 @@ -61,6 +61,11 @@ #include "oasis.h" #include "dg_scripts.h" +/*#define HAVE_ADNS*/ +#ifdef HAVE_ADNS +#include +#endif + #ifdef HAVE_ARPA_TELNET_H #include #else @@ -170,6 +175,14 @@ void sedit_save_to_disk(zone_vnum zone_num); void zedit_save_to_disk(zone_vnum zone_num); int real_zone(int number); +#ifdef HAVE_ADNS +adns_state dns_state; +struct dns_query_list_data { + char *ip; + adns_query query; + struct dns_query_list_data *next; +} *dns_queries; +#endif #ifdef __CXREF__ #undef FD_ZERO @@ -182,6 +195,115 @@ #define FD_CLR(x, y) #endif +#ifdef HAVE_ADNS +void check_dns() +{ + char ip[256]; + char host[256]; + adns_answer *ans; + void *ctx; + int v = 0; + struct dns_query_list_data *req, *req_next, *tmp; + struct descriptor_data *d; + + for(req = dns_queries, tmp = NULL; req; req = req_next) { + req_next = req->next; + ctx = NULL; + ans = NULL; + + v = adns_check(dns_state, &req->query, &ans, &ctx); + if (!ans || ans->type == adns_r_none) { + tmp = req; + continue; + } + if (!tmp) + dns_queries = req_next; + else tmp->next = req_next; + if (!ans->nrrs || ans->status == adns_s_nodata || ans->status == adns_s_nxdomain) + { + log("Unable to resolve %s: %s", req->ip, + adns_strerror(ans->status)); + for(d = descriptor_list; d; d = d->next) + if (d->doing_dns && !str_cmp(d->host, req->ip)) + d->doing_dns = 0; + if (req->ip) + free(req->ip); + free(req); + break; + } + /* ip -> host */ + sprintf(ip, "%.100s", req->ip); + sprintf(host, "%.100s", ans->rrs.str[0]); + for(d = descriptor_list; d; d = d->next) { + if (d->doing_dns && !str_cmp(d->host, ip)) { + strcpy(d->host, host); + d->doing_dns = 0; + /* The resolved address is Banned! */ + if (isbanned(d->host) == BAN_ALL) { + sprintf(buf2, "Connection attempt denied from [%s]", d->host); + mudlog(buf2, CMP, LVL_GOD, TRUE); + STATE(d) = CON_CLOSE; + } + } + } + if (req->ip) + free(req->ip); + free(req); + } + +} + + +char *ip2ptr(char *host) +{ + static char buf[HOST_LENGTH + 25]; + unsigned short int a, b, c, d; + + skip_spaces(&(char *)host); + if ( sscanf(host, "%hu.%hu.%hu.%hu", &a, &b, &c, &d) < 4 ) { + return strcpy(buf, host); + } + sprintf(buf, "%hu.%hu.%hu.%hu.in-addr.arpa.", + d, c, b, a); + return buf; +} + +int query_dns(char *host) +{ + struct dns_query_list_data *req; + + if (!host || !*host) + return -1; + + /* One query will take care of all descriptors from the machine. */ + for(req = dns_queries; req; req = req->next) + if (!str_cmp(req->ip, host)) + break; + if (req) + return 0; + + do { + CREATE(req, struct dns_query_list_data, 1); + + req->ip = str_dup(host); + if (adns_submit(dns_state, ip2ptr(host), adns_r_ptr, + adns_qf_owner|adns_qf_cname_loose, req, &req->query)) + { + perror("adns_submit"); + if (req->ip) free(req->ip); + free(req); + return -1; + } + + req->next = dns_queries; + dns_queries = req; + } while(0); + + check_dns(); + return 0; +} + +#endif /*********************************************************************** * main game loop and related stuff * @@ -345,6 +467,9 @@ void init_game(ush_int port) { socket_t mother_desc; +#ifdef HAVE_ADNS + int errv = 0; +#endif /* We don't want to restart if we crash before we get up. */ touch(KILLSCRIPT_FILE); @@ -364,6 +489,15 @@ signal_setup(); #endif +#ifdef HAVE_ADNS + log("Asynchronous dns system."); + errv = adns_init(&dns_state, adns_if_debug|adns_if_noenv|adns_if_noautosys, 0); + if (errv) { + perror("adns_init"); + exit(0); + } +#endif + /* If we made it this far, we will be able to restart without problem. */ remove(KILLSCRIPT_FILE); @@ -584,7 +718,10 @@ char comm[MAX_INPUT_LENGTH]; struct descriptor_data *d, *next_d; int pulse = 0, missed_pulses = 0, maxdesc, aliased; - + int high_fd = 0; +#ifdef HAVE_ADNS + struct timeval tvNow; +#endif /* initialize various time values */ null_time.tv_sec = 0; null_time.tv_usec = 0; @@ -666,11 +803,22 @@ timediff(&timeout, &last_time, &now); } while (timeout.tv_usec || timeout.tv_sec); + high_fd = maxdesc; +#ifdef HAVE_ADNS + gettimeofday(&tvNow, NULL); + adns_beforeselect(dns_state, &high_fd, &input_set, &output_set, &exc_set, + NULL, NULL, &tvNow); +#endif /* Poll (without blocking) for new input, output, and exceptions */ - if (select(maxdesc + 1, &input_set, &output_set, &exc_set, &null_time) < 0) { + if (select(high_fd + 1, &input_set, &output_set, &exc_set, &null_time) < 0) { perror("SYSERR: Select poll"); return; } +#ifdef HAVE_ADNS + adns_afterselect(dns_state, high_fd, &input_set, &output_set, &exc_set, + &tvNow); + check_dns(); +#endif /* If there are new connections waiting, accept them. */ if (FD_ISSET(mother_desc, &input_set)) new_descriptor(mother_desc); @@ -688,6 +836,8 @@ /* Process descriptors with input pending */ for (d = descriptor_list; d; d = next_d) { next_d = d->next; + if (d->doing_dns) + continue; if (FD_ISSET(d->descriptor, &input_set)) if (process_input(d) < 0) close_socket(d); @@ -1216,7 +1366,9 @@ static int last_desc = 0; /* last descriptor number */ struct descriptor_data *newd; struct sockaddr_in peer; +#ifndef HAVE_ADNS struct hostent *from; +#endif /* accept the new connection */ i = sizeof(peer); @@ -1246,21 +1398,40 @@ CREATE(newd, struct descriptor_data, 1); memset((char *) newd, 0, sizeof(struct descriptor_data)); + newd->addr = peer.sin_addr; + +#ifdef HAVE_ADNS + if (nameserver_is_slow) { + strncpy(newd->host, (char *)inet_ntoa(newd->addr), HOST_LENGTH); + *(newd->host + HOST_LENGTH) = '\0'; + } + else + { + strncpy(newd->host, (char *)inet_ntoa(newd->addr), HOST_LENGTH); + *(newd->host + HOST_LENGTH) = '\0'; + if (newd && newd->host && *newd->host) { + newd->doing_dns = 1; + if ( query_dns(newd->host) < 0) + newd->doing_dns = 0; + } + } +#else /* find the sitename */ - if (nameserver_is_slow || !(from = gethostbyaddr((char *) &peer.sin_addr, - sizeof(peer.sin_addr), AF_INET))) { + if (nameserver_is_slow || !(from = gethostbyaddr((char *) &newd->addr, + sizeof(newd->addr), AF_INET))) { /* resolution failed */ if (!nameserver_is_slow) perror("SYSERR: gethostbyaddr"); /* find the numeric site address */ - strncpy(newd->host, (char *)inet_ntoa(peer.sin_addr), HOST_LENGTH); + strncpy(newd->host, (char *)inet_ntoa(newd->addr), HOST_LENGTH); *(newd->host + HOST_LENGTH) = '\0'; } else { strncpy(newd->host, from->h_name, HOST_LENGTH); *(newd->host + HOST_LENGTH) = '\0'; } +#endif /* determine if the site is banned */ if (isbanned(newd->host) == BAN_ALL) { @@ -1897,6 +2068,8 @@ for (d = descriptor_list; d; d = next_d) { next_d = d->next; + if (d->doing_dns) + continue; if (STATE(d) != CON_PASSWORD && STATE(d) != CON_GET_NAME) continue; if (!d->idle_tics) { diff --unified=3 ../src-orig/config.c ./config.c --- ../src-orig/config.c Sat Mar 25 22:11:47 2000 +++ ./config.c Wed Jun 28 14:15:57 2000 @@ -247,7 +247,7 @@ * the SLOWNS command from within the MUD. */ -int nameserver_is_slow = YES; +int nameserver_is_slow = NO; const char *MENU = diff --unified=3 ../src-orig/structs.h ./structs.h --- ../src-orig/structs.h Fri Apr 7 04:24:26 2000 +++ ./structs.h Wed Jun 28 15:31:00 2000 @@ -1071,6 +1071,8 @@ int history_pos; /* Circular array position. */ int bufptr; /* ptr to end of current output */ int bufspace; /* space left in the output buffer */ + bool doing_dns; /* awaiting dns response? */ + struct in_addr addr; /* physical ip address in in_addr form */ struct txt_block *large_outbuf; /* ptr to large buffer, if we need it */ struct txt_q input; /* q of unprocessed input */ struct char_data *character; /* linked to char */ diff --unified=3 ../src-orig/sysdep.h ./sysdep.h --- ../src-orig/sysdep.h Sat Mar 25 22:11:47 2000 +++ ./sysdep.h Wed Jun 28 15:44:03 2000 @@ -195,17 +195,25 @@ #define assert(arg) #endif - -/* Header files only used in comm.c and some of the utils */ - -#if defined(__COMM_C__) || defined(CIRCLE_UTIL) - #ifndef HAVE_STRUCT_IN_ADDR struct in_addr { unsigned long int s_addr; /* for inet_addr, etc. */ } #endif +#ifdef HAVE_NETINET_IN_H +# include +#endif + +#ifdef HAVE_ARPA_INET_H +# include +#endif + + +/* Header files only used in comm.c and some of the utils */ + +#if defined(__COMM_C__) || defined(CIRCLE_UTIL) + #ifdef HAVE_SYS_SELECT_H #include #endif @@ -228,14 +236,6 @@ #ifdef HAVE_SYS_WAIT_H # include -#endif - -#ifdef HAVE_NETINET_IN_H -# include -#endif - -#ifdef HAVE_ARPA_INET_H -# include #endif #ifdef HAVE_NETDB_H