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Diffstat (limited to 'source/nameservresp.c')
| -rw-r--r-- | source/nameservresp.c | 822 |
1 files changed, 822 insertions, 0 deletions
diff --git a/source/nameservresp.c b/source/nameservresp.c new file mode 100644 index 00000000000..a4cda7cdfb5 --- /dev/null +++ b/source/nameservresp.c @@ -0,0 +1,822 @@ +/* + Unix SMB/Netbios implementation. + Version 1.9. + NBT netbios routines and daemon - version 2 + Copyright (C) Andrew Tridgell 1994-1996 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + Revision History: + + Module name: nameservresp.c + + 14 jan 96: lkcl@pires.co.uk + added multiple workgroup domain master support + + 05 jul 96: lkcl@pires.co.uk + created module nameservresp containing NetBIOS response functions + +*/ + +#include "includes.h" + +extern int ClientNMB; + +extern int DEBUGLEVEL; + +extern pstring scope; +extern struct in_addr ipzero; + +#define GET_TTL(ttl) ((ttl)?MIN(ttl,lp_max_ttl()):lp_max_ttl()) + + +/**************************************************************************** + response for a reg release received. samba has asked a WINS server if it + could release a name. + **************************************************************************/ +static void response_name_release(struct subnet_record *d, + struct packet_struct *p) +{ + struct nmb_packet *nmb = &p->packet.nmb; + char *name = nmb->question.question_name.name; + int type = nmb->question.question_name.name_type; + + DEBUG(4,("response name release received\n")); + + if (nmb->header.rcode == 0 && nmb->answers->rdata) + { + /* IMPORTANT: see expire_netbios_response_entries() */ + + struct in_addr found_ip; + putip((char*)&found_ip,&nmb->answers->rdata[2]); + + /* NOTE: we only release our own names at present */ + if (ismyip(found_ip)) + { + name_unregister_work(d,name,type); + } + else + { + DEBUG(2,("name release for different ip! %s %s\n", + inet_ntoa(found_ip), + namestr(&nmb->question.question_name))); + } + } + else + { + DEBUG(2,("name release for %s rejected!\n", + namestr(&nmb->question.question_name))); + + /* XXXX PANIC! what to do if it's one of samba's own names? */ + + /* XXXX do we honestly care if our name release was rejected? + only if samba is issuing the release on behalf of some out-of-sync + server. if it's one of samba's SELF names, we don't care. */ + } +} + + +/**************************************************************************** +response for a reg request received +**************************************************************************/ +static void response_name_reg(struct subnet_record *d, struct packet_struct *p) +{ + struct nmb_packet *nmb = &p->packet.nmb; + char *name = nmb->question.question_name.name; + int type = nmb->question.question_name.name_type; + BOOL bcast = nmb->header.nm_flags.bcast; + + DEBUG(4,("response name registration received!\n")); + + if (nmb->header.rcode == 0 && nmb->answers->rdata) + { + /* IMPORTANT: see expire_netbios_response_entries() */ + + int nb_flags = nmb->answers->rdata[0]; + int ttl = nmb->answers->ttl; + struct in_addr found_ip; + + putip((char*)&found_ip,&nmb->answers->rdata[2]); + + name_register_work(d,name,type,nb_flags,ttl,found_ip,bcast); + } + else + { + DEBUG(1,("name registration for %s rejected!\n", + namestr(&nmb->question.question_name))); + + /* oh dear. we have problems. possibly unbecome a master browser. */ + name_unregister_work(d,name,type); + } +} + + +/**************************************************************************** + response from a name query announce host + NAME_QUERY_ANNOUNCE_HOST is dealt with here + ****************************************************************************/ +static void response_announce_host(struct nmb_name *ans_name, + struct nmb_packet *nmb, + struct response_record *n, struct subnet_record *d) +{ + DEBUG(4, ("Name query at %s ip %s - ", + namestr(&n->name), inet_ntoa(n->send_ip))); + + if (!name_equal(&n->name, ans_name)) + { + /* someone gave us the wrong name as a reply. oops. */ + /* XXXX should say to them 'oi! release that name!' */ + + DEBUG(4,("unexpected name received: %s\n", namestr(ans_name))); + return; + } + + if (nmb->header.rcode == 0 && nmb->answers->rdata) + { + /* we had sent out a name query to the current owner + of a name because someone else wanted it. now they + have responded saying that they still want the name, + so the other host can't have it. + */ + + /* first check all the details are correct */ + + int nb_flags = nmb->answers->rdata[0]; + struct in_addr found_ip; + + putip((char*)&found_ip,&nmb->answers->rdata[2]); + + if (nb_flags != n->nb_flags) + { + /* someone gave us the wrong nb_flags as a reply. oops. */ + /* XXXX should say to them 'oi! release that name!' */ + + DEBUG(4,("expected nb_flags: %d\n", n->nb_flags)); + DEBUG(4,("unexpected nb_flags: %d\n", nb_flags)); + return; + } + + /* do an announce host */ + do_announce_host(ANN_HostAnnouncement, + n->my_name , 0x00, d->myip, + n->name.name, 0x1d, found_ip, + n->ttl, + n->my_name, n->server_type, n->my_comment); + } + else + { + /* XXXX negative name query response. no master exists. oops */ + } +} + + +/**************************************************************************** + response from a name query server check. states of type NAME_QUERY_DOM_SRV_CHK, + NAME_QUERY_SRV_CHK, and NAME_QUERY_FIND_MST dealt with here. + ****************************************************************************/ +static void response_server_check(struct nmb_name *ans_name, + struct response_record *n, struct subnet_record *d) +{ + /* issue another state: this time to do a name status check */ + + enum state_type cmd = (n->state == NAME_QUERY_DOM_SRV_CHK) ? + NAME_STATUS_DOM_SRV_CHK : NAME_STATUS_SRV_CHK; + + /* initiate a name status check on the server that replied */ + queue_netbios_packet(d,ClientNMB,NMB_STATUS, cmd, + ans_name->name, ans_name->name_type, + 0,0,0,NULL,NULL, + False,False,n->send_ip,n->reply_to_ip); +} + + +/**************************************************************************** + interpret a node status response. this is pretty hacked: we need two bits of + info. a) the name of the workgroup b) the name of the server. it will also + add all the names it finds into the namelist. +****************************************************************************/ +static BOOL interpret_node_status(struct subnet_record *d, + char *p, struct nmb_name *name,int t, + char *serv_name, struct in_addr ip, BOOL bcast) +{ + int level = t==0x20 ? 4 : 0; + int numnames = CVAL(p,0); + BOOL found = False; + + DEBUG(level,("received %d names\n",numnames)); + + p += 1; + + if (serv_name) *serv_name = 0; + + while (numnames--) + { + char qname[17]; + int type; + fstring flags; + int nb_flags; + + BOOL group = False; + BOOL add = False; + + *flags = 0; + + StrnCpy(qname,p,15); + type = CVAL(p,15); + nb_flags = p[16]; + trim_string(qname,NULL," "); + + p += 18; + + if (NAME_GROUP (nb_flags)) { strcat(flags,"<GROUP> "); group=True;} + if (NAME_BFLAG (nb_flags)) { strcat(flags,"B "); } + if (NAME_PFLAG (nb_flags)) { strcat(flags,"P "); } + if (NAME_MFLAG (nb_flags)) { strcat(flags,"M "); } + if (NAME_HFLAG (nb_flags)) { strcat(flags,"H "); } + if (NAME_DEREG (nb_flags)) { strcat(flags,"<DEREGISTERING> "); } + if (NAME_CONFLICT (nb_flags)) { strcat(flags,"<CONFLICT> "); add=True;} + if (NAME_ACTIVE (nb_flags)) { strcat(flags,"<ACTIVE> "); add=True; } + if (NAME_PERMANENT(nb_flags)) { strcat(flags,"<PERMANENT> "); add=True;} + + /* might as well update our namelist while we're at it */ + if (add) + { + struct in_addr nameip; + enum name_source src; + + if (ismyip(ip)) { + nameip = ipzero; + src = SELF; + } else { + nameip = ip; + src = STATUS_QUERY; + } + add_netbios_entry(d,qname,type,nb_flags,2*60*60,src,nameip,True,bcast); + } + + /* we want the server name */ + if (serv_name && !*serv_name && !group && t == 0) + { + StrnCpy(serv_name,qname,15); + serv_name[15] = 0; + } + + /* looking for a name and type? */ + if (name && !found && (t == type)) + { + /* take a guess at some of the name types we're going to ask for. + evaluate whether they are group names or no... */ + if (((t == 0x1b || t == 0x1d ) && !group) || + ((t == 0x20 || t == 0x1c || t == 0x1e) && group)) + { + found = True; + make_nmb_name(name,qname,type,scope); + } + } + + DEBUG(level,("\t%s(0x%x)\t%s\n",qname,type,flags)); + } + DEBUG(level,("num_good_sends=%d num_good_receives=%d\n", + IVAL(p,20),IVAL(p,24))); + return found; +} + + +/**************************************************************************** + response from a name status check. states of type NAME_STATUS_DOM_SRV_CHK + and NAME_STATUS_SRV_CHK dealt with here. + ****************************************************************************/ +static void response_name_status_check(struct in_addr ip, + struct nmb_packet *nmb, BOOL bcast, + struct response_record *n, struct subnet_record *d) +{ + /* NMB_STATUS arrives: contains workgroup name and server name required. + amongst other things. */ + + struct nmb_name name; + fstring serv_name; + + if (interpret_node_status(d,nmb->answers->rdata, + &name,name.name_type,serv_name,ip,bcast)) + { + if (*serv_name) + { + sync_server(n->state,serv_name, + name.name,name.name_type, n->send_ip); + } + } + else + { + DEBUG(1,("No 0x1d name type in interpret_node_status()\n")); + } +} + + +/**************************************************************************** + response from a name query for secured WINS registration. a state of + NAME_REGISTER_CHALLENGE is dealt with here. + ****************************************************************************/ +static void response_name_query_register(struct nmb_packet *nmb, + struct nmb_name *ans_name, + struct response_record *n, struct subnet_record *d) +{ + struct in_addr register_ip; + BOOL new_owner; + + DEBUG(4, ("Name query at %s ip %s - ", + namestr(&n->name), inet_ntoa(n->send_ip))); + + if (!name_equal(&n->name, ans_name)) + { + /* someone gave us the wrong name as a reply. oops. */ + /* XXXX should say to them 'oi! release that name!' */ + + DEBUG(4,("unexpected name received: %s\n", namestr(ans_name))); + return; + } + + if (nmb->header.rcode == 0 && nmb->answers->rdata) + { + /* we had sent out a name query to the current owner + of a name because someone else wanted it. now they + have responded saying that they still want the name, + so the other host can't have it. + */ + + /* first check all the details are correct */ + + int nb_flags = nmb->answers->rdata[0]; + struct in_addr found_ip; + + putip((char*)&found_ip,&nmb->answers->rdata[2]); + + if (nb_flags != n->nb_flags) + { + /* someone gave us the wrong nb_flags as a reply. oops. */ + /* XXXX should say to them 'oi! release that name!' */ + + DEBUG(4,("expected nb_flags: %d\n", n->nb_flags)); + DEBUG(4,("unexpected nb_flags: %d\n", nb_flags)); + return; + } + + if (!ip_equal(n->send_ip, found_ip)) + { + /* someone gave us the wrong ip as a reply. oops. */ + /* XXXX should say to them 'oi! release that name!' */ + + DEBUG(4,("expected ip: %s\n", inet_ntoa(n->send_ip))); + DEBUG(4,("unexpected ip: %s\n", inet_ntoa(found_ip))); + return; + } + + DEBUG(4, (" OK: %s\n", inet_ntoa(found_ip))); + + /* fine: now tell the other host they can't have the name */ + register_ip = n->send_ip; + new_owner = False; + } + else + { + DEBUG(4, (" NEGATIVE RESPONSE!\n")); + + /* the owner didn't want the name: the other host can have it */ + register_ip = n->reply_to_ip; + new_owner = True; + } + + /* register the old or the new owners' ip */ + add_name_respond(d, n->fd, d->myip, n->response_id,&n->name,n->nb_flags, + GET_TTL(0), register_ip, + new_owner, n->reply_to_ip); +} + + +/**************************************************************************** + response from a name query to sync browse lists or to update our netbios + entry. states of type NAME_QUERY_SYNC and NAME_QUERY_CONFIRM + ****************************************************************************/ +static void response_name_query_sync(struct nmb_packet *nmb, + struct nmb_name *ans_name, BOOL bcast, + struct response_record *n, struct subnet_record *d) +{ + DEBUG(4, ("Name query at %s ip %s - ", + namestr(&n->name), inet_ntoa(n->send_ip))); + + if (!name_equal(&n->name, ans_name)) + { + /* someone gave us the wrong name as a reply. oops. */ + DEBUG(4,("unexpected name received: %s\n", namestr(ans_name))); + return; + } + + if (nmb->header.rcode == 0 && nmb->answers->rdata) + { + int nb_flags = nmb->answers->rdata[0]; + struct in_addr found_ip; + + putip((char*)&found_ip,&nmb->answers->rdata[2]); + + if (!ip_equal(n->send_ip, found_ip)) + { + /* someone gave us the wrong ip as a reply. oops. */ + DEBUG(4,("expected ip: %s\n", inet_ntoa(n->send_ip))); + DEBUG(4,("unexpected ip: %s\n", inet_ntoa(found_ip))); + return; + } + + DEBUG(4, (" OK: %s\n", inet_ntoa(found_ip))); + + if (n->state == NAME_QUERY_SYNC_LOCAL || + n->state == NAME_QUERY_SYNC_REMOTE) + { + struct work_record *work = NULL; + if ((work = find_workgroupstruct(d, ans_name->name, False))) + { + BOOL local_list_only = n->state == NAME_QUERY_SYNC_LOCAL; + + /* the server is there: sync quick before it (possibly) dies! */ + sync_browse_lists(d, work, ans_name->name, ans_name->name_type, + found_ip, local_list_only); + } + } + else + { + /* update our netbios name list (re-register it if necessary) */ + add_netbios_entry(d, ans_name->name, ans_name->name_type, + nb_flags,GET_TTL(0),REGISTER, + found_ip,False,!bcast); + } + } + else + { + DEBUG(4, (" NEGATIVE RESPONSE!\n")); + + if (n->state == NAME_QUERY_CONFIRM) + { + /* XXXX remove_netbios_entry()? */ + /* lots of things we ought to do, here. if we get here, + then we're in a mess: our name database doesn't match + reality. sort it out + */ + remove_netbios_name(d,n->name.name, n->name.name_type, + REGISTER,n->send_ip); + } + } +} + + +/**************************************************************************** + report the response record type + ****************************************************************************/ +static void debug_rr_type(int rr_type) +{ + switch (rr_type) + { + case NMB_STATUS: DEBUG(3,("Name status ")); break; + case NMB_QUERY : DEBUG(3,("Name query ")); break; + case NMB_REG : DEBUG(3,("Name registration ")); break; + case NMB_REL : DEBUG(3,("Name release ")); break; + default : DEBUG(1,("wrong response packet type received")); break; + } +} + +/**************************************************************************** + report the response record nmbd state + ****************************************************************************/ +void debug_state_type(int state) +{ + /* report the state type to help debugging */ + switch (state) + { + case NAME_QUERY_DOM_SRV_CHK : DEBUG(4,("MASTER_SVR_CHECK\n")); break; + case NAME_QUERY_SRV_CHK : DEBUG(4,("NAME_QUERY_SRV_CHK\n")); break; + case NAME_QUERY_FIND_MST : DEBUG(4,("NAME_QUERY_FIND_MST\n")); break; + case NAME_QUERY_MST_CHK : DEBUG(4,("NAME_QUERY_MST_CHK\n")); break; + case NAME_QUERY_CONFIRM : DEBUG(4,("NAME_QUERY_CONFIRM\n")); break; + case NAME_QUERY_SYNC_LOCAL : DEBUG(4,("NAME_QUERY_SYNC_LOCAL\n")); break; + case NAME_QUERY_SYNC_REMOTE : DEBUG(4,("NAME_QUERY_SYNC_REMOTE\n")); break; + case NAME_QUERY_ANNOUNCE_HOST: DEBUG(4,("NAME_QUERY_ANNCE_HOST\n"));break; + + case NAME_REGISTER : DEBUG(4,("NAME_REGISTER\n")); break; + case NAME_REGISTER_CHALLENGE : DEBUG(4,("NAME_REGISTER_CHALLENGE\n"));break; + + case NAME_RELEASE : DEBUG(4,("NAME_RELEASE\n")); break; + + case NAME_STATUS_DOM_SRV_CHK : DEBUG(4,("NAME_STAT_MST_CHK\n")); break; + case NAME_STATUS_SRV_CHK : DEBUG(4,("NAME_STATUS_SRV_CHK\n")); break; + + default: break; + } +} + +/**************************************************************************** + report any problems with the fact that a response has been received. + + (responses for certain types of operations are only expected from one host) + ****************************************************************************/ +static BOOL response_problem_check(struct response_record *n, + struct nmb_packet *nmb, char *qname) +{ + switch (nmb->answers->rr_type) + { + case NMB_REL: + { + if (n->num_msgs > 1) + { + DEBUG(1,("more than one release name response received!\n")); + return True; + } + break; + } + + case NMB_REG: + { + if (n->num_msgs > 1) + { + DEBUG(1,("more than one register name response received!\n")); + return True; + } + break; + } + + case NMB_QUERY: + { + if (n->num_msgs > 1) + { + if (nmb->header.rcode == 0 && nmb->answers->rdata) + { + int nb_flags = nmb->answers->rdata[0]; + + if ((!NAME_GROUP(nb_flags))) + { + /* oh dear. more than one person responded to a unique name. + there is either a network problem, a configuration problem + or a server is mis-behaving */ + + /* XXXX mark the name as in conflict, and then let the + person who just responded know that they must also mark it + as in conflict, and therefore must NOT use it. + see rfc1001.txt 15.1.3.5 */ + + /* this may cause problems for some early versions of nmbd */ + + switch (n->state) + { + case NAME_QUERY_FIND_MST: + { + /* query for ^1^2__MSBROWSE__^2^1 expect lots of responses */ + return False; + } + case NAME_QUERY_ANNOUNCE_HOST: + case NAME_QUERY_DOM_SRV_CHK: + case NAME_QUERY_SRV_CHK: + case NAME_QUERY_MST_CHK: + { + if (!strequal(qname,n->name.name)) + { + /* one subnet, one master browser per workgroup */ + /* XXXX force an election? */ + + DEBUG(3,("more than one master browser replied!\n")); + return True; + } + break; + } + default: break; + } + DEBUG(3,("Unique Name conflict detected!\n")); + return True; + } + } + else + { + /* we have received a negative reply, having already received + at least one response (pos/neg). something's really wrong! */ + + DEBUG(3,("wierd name query problem detected!\n")); + return True; + } + } + } + } + return False; +} + +/**************************************************************************** + check that the response received is compatible with the response record + ****************************************************************************/ +static BOOL response_compatible(struct response_record *n, + struct nmb_packet *nmb) +{ + switch (n->state) + { + case NAME_RELEASE: + { + if (nmb->answers->rr_type != NMB_REL) + { + DEBUG(1,("Name release reply has wrong answer rr_type\n")); + return False; + } + break; + } + + case NAME_REGISTER: + { + if (nmb->answers->rr_type != NMB_REG) + { + DEBUG(1,("Name register reply has wrong answer rr_type\n")); + return False; + } + break; + } + + case NAME_REGISTER_CHALLENGE: /* this is a query: we then do a register */ + case NAME_QUERY_CONFIRM: + case NAME_QUERY_ANNOUNCE_HOST: + case NAME_QUERY_SYNC_LOCAL: + case NAME_QUERY_SYNC_REMOTE: + case NAME_QUERY_DOM_SRV_CHK: + case NAME_QUERY_SRV_CHK: + case NAME_QUERY_FIND_MST: + case NAME_QUERY_MST_CHK: + { + if (nmb->answers->rr_type != NMB_QUERY) + { + DEBUG(1,("Name query reply has wrong answer rr_type\n")); + return False; + } + break; + } + + case NAME_STATUS_DOM_SRV_CHK: + case NAME_STATUS_SRV_CHK: + { + if (nmb->answers->rr_type != NMB_STATUS) + { + DEBUG(1,("Name status reply has wrong answer rr_type\n")); + return False; + } + break; + } + + default: + { + DEBUG(1,("unknown state type received in response_netbios_packet\n")); + return False; + } + } + return True; +} + + +/**************************************************************************** + process the response packet received + ****************************************************************************/ +static void response_process(struct subnet_record *d, struct packet_struct *p, + struct response_record *n, struct nmb_packet *nmb, + BOOL bcast, struct nmb_name *ans_name) +{ + switch (n->state) + { + case NAME_RELEASE: + { + response_name_release(d, p); + break; + } + + case NAME_REGISTER: + { + response_name_reg(d, p); + break; + } + + case NAME_REGISTER_CHALLENGE: + { + response_name_query_register(nmb, ans_name, n, d); + break; + } + + case NAME_QUERY_DOM_SRV_CHK: + case NAME_QUERY_SRV_CHK: + case NAME_QUERY_FIND_MST: + { + response_server_check(ans_name, n, d); + break; + } + + case NAME_STATUS_DOM_SRV_CHK: + case NAME_STATUS_SRV_CHK: + { + response_name_status_check(p->ip, nmb, bcast, n, d); + break; + } + + case NAME_QUERY_ANNOUNCE_HOST: + { + response_announce_host(ans_name, nmb, n, d); + break; + } + + case NAME_QUERY_CONFIRM: + case NAME_QUERY_SYNC_LOCAL: + case NAME_QUERY_SYNC_REMOTE: + { + response_name_query_sync(nmb, ans_name, bcast, n, d); + break; + } + case NAME_QUERY_MST_CHK: + { + /* no action required here. it's when NO responses are received + that we need to do something. see expire_name_query_entries() */ + + DEBUG(4, ("Master browser exists for %s at %s (just checking!)\n", + namestr(&n->name), inet_ntoa(n->send_ip))); + break; + } + + default: + { + DEBUG(1,("unknown state type received in response_netbios_packet\n")); + break; + } + } +} + + +/**************************************************************************** + response from a netbios packet. + ****************************************************************************/ +void response_netbios_packet(struct packet_struct *p) +{ + struct nmb_packet *nmb = &p->packet.nmb; + struct nmb_name *question = &nmb->question.question_name; + struct nmb_name *ans_name = NULL; + char *qname = question->name; + BOOL bcast = nmb->header.nm_flags.bcast; + struct response_record *n; + struct subnet_record *d = NULL; + + if (!(n = find_response_record(&d,nmb->header.name_trn_id))) { + DEBUG(2,("unknown netbios response (received late or from nmblookup?)\n")); + return; + } + + if (!d) + { + DEBUG(2,("response packet: subnet %s not known\n", inet_ntoa(p->ip))); + return; + } + + /* args wrong way round: spotted by ccm@shentel.net */ + if (!same_net(d->bcast_ip, p->ip, d->mask_ip)) /* copes with WINS 'subnet' */ + { + DEBUG(2,("response from %s. ", inet_ntoa(p->ip))); + DEBUG(2,("expected on subnet %s. hmm.\n", inet_ntoa(d->bcast_ip))); + return; + } + + if (nmb->answers == NULL) + { + /* hm. the packet received was a response, but with no answer. wierd! */ + DEBUG(2,("NMB packet response from %s (bcast=%s) - UNKNOWN\n", + inet_ntoa(p->ip), BOOLSTR(bcast))); + return; + } + + ans_name = &nmb->answers->rr_name; + DEBUG(3,("response for %s from %s (bcast=%s)\n", + namestr(ans_name), inet_ntoa(p->ip), BOOLSTR(bcast))); + + debug_rr_type(nmb->answers->rr_type); + + n->num_msgs++; /* count number of responses received */ + n->repeat_count = 0; /* don't resend: see expire_netbios_packets() */ + + debug_state_type(n->state); + + /* problem checking: multiple responses etc */ + if (response_problem_check(n, nmb, qname)) + return; + + /* now check whether the 'state' has received the correct type of response */ + if (!response_compatible(n, nmb)) + return; + + /* now deal with the current state */ + response_process(d, p, n, nmb, bcast, ans_name); +} + + |