diff options
Diffstat (limited to 'source3/nmbd/nmbd_nameregister.c')
| -rw-r--r-- | source3/nmbd/nmbd_nameregister.c | 608 |
1 files changed, 608 insertions, 0 deletions
diff --git a/source3/nmbd/nmbd_nameregister.c b/source3/nmbd/nmbd_nameregister.c new file mode 100644 index 0000000..4b7b6c6 --- /dev/null +++ b/source3/nmbd/nmbd_nameregister.c @@ -0,0 +1,608 @@ +/* + Unix SMB/CIFS implementation. + NBT netbios routines and daemon - version 2 + Copyright (C) Andrew Tridgell 1994-1998 + Copyright (C) Luke Kenneth Casson Leighton 1994-1998 + Copyright (C) Jeremy Allison 1994-2003 + + 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 3 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, see <http://www.gnu.org/licenses/>. + +*/ + +#include "includes.h" +#include "nmbd/nmbd.h" +#include "lib/util/string_wrappers.h" + +/* forward declarations */ +static void wins_next_registration(struct response_record *rrec); + + +/**************************************************************************** + Deal with a response packet when registering one of our names. +****************************************************************************/ + +static void register_name_response(struct subnet_record *subrec, + struct response_record *rrec, struct packet_struct *p) +{ + /* + * If we are registering broadcast, then getting a response is an + * error - we do not have the name. If we are registering unicast, + * then we expect to get a response. + */ + + struct nmb_packet *nmb = &p->packet.nmb; + bool bcast = nmb->header.nm_flags.bcast; + bool success = True; + struct nmb_name *question_name = &rrec->packet->packet.nmb.question.question_name; + struct nmb_name *answer_name = &nmb->answers->rr_name; + struct nmb_packet *sent_nmb = &rrec->packet->packet.nmb; + int ttl = 0; + uint16_t nb_flags = 0; + struct in_addr register_ip; + fstring reg_name; + + putip(®ister_ip,&sent_nmb->additional->rdata[2]); + fstrcpy(reg_name, inet_ntoa(register_ip)); + + if (subrec == unicast_subnet) { + /* we know that this wins server is definitely alive - for the moment! */ + wins_srv_alive(rrec->packet->ip, register_ip); + } + + /* Sanity check. Ensure that the answer name in the incoming packet is the + same as the requested name in the outgoing packet. */ + + if(!question_name || !answer_name) { + DEBUG(0,("register_name_response: malformed response (%s is NULL).\n", + question_name ? "question_name" : "answer_name" )); + return; + } + + if(!nmb_name_equal(question_name, answer_name)) { + DEBUG(0,("register_name_response: Answer name %s differs from question name %s.\n", + nmb_namestr(answer_name), nmb_namestr(question_name))); + return; + } + + if(bcast) { + /* + * Special hack to cope with old Samba nmbd's. + * Earlier versions of Samba (up to 1.9.16p11) respond + * to a broadcast name registration of WORKGROUP<1b> when + * they should not. Hence, until these versions are gone, + * we should treat such errors as success for this particular + * case only. jallison@whistle.com. + */ + +#if 1 /* OLD_SAMBA_SERVER_HACK */ + unstring ans_name; + pull_ascii_nstring(ans_name, sizeof(ans_name), answer_name->name); + if((nmb->header.rcode == ACT_ERR) && strequal(lp_workgroup(), ans_name) && + (answer_name->name_type == 0x1b)) { + /* Pretend we did not get this. */ + rrec->num_msgs--; + + DEBUG(5,("register_name_response: Ignoring broadcast response to registration of name %s due to old Samba server bug.\n", + nmb_namestr(answer_name))); + return; + } +#endif /* OLD_SAMBA_SERVER_HACK */ + + /* Someone else has the name. Log the problem. */ + DEBUG(1,("register_name_response: Failed to register name %s IP %s on subnet %s via broadcast. Error code was %d. Reject came from IP %s\n", + nmb_namestr(answer_name), + reg_name, + subrec->subnet_name, nmb->header.rcode, inet_ntoa(p->ip))); + success = False; + } else { + if (!ip_equal_v4(rrec->packet->ip, p->ip)) { + DEBUG(5,("register_name_response: Ignoring WINS server response " + "from IP %s, for name %s. We sent to IP %s\n", + inet_ntoa(p->ip), + nmb_namestr(answer_name), + inet_ntoa(rrec->packet->ip))); + return; + } + /* Unicast - check to see if the response allows us to have the name. */ + if (nmb->header.opcode == NMB_WACK_OPCODE) { + /* WINS server is telling us to wait. Pretend we didn't get + the response but don't send out any more register requests. */ + + DEBUG(5,("register_name_response: WACK from WINS server %s in registering name %s IP %s\n", + inet_ntoa(p->ip), nmb_namestr(answer_name), reg_name)); + + rrec->repeat_count = 0; + /* How long we should wait for. */ + rrec->repeat_time = p->timestamp + nmb->answers->ttl; + rrec->num_msgs--; + return; + } else if (nmb->header.rcode != 0) { + /* Error code - we didn't get the name. */ + success = False; + + DEBUG(0,("register_name_response: %sserver at IP %s rejected our name registration of %s IP %s with error code %d.\n", + subrec==unicast_subnet?"WINS ":"", + inet_ntoa(p->ip), + nmb_namestr(answer_name), + reg_name, + nmb->header.rcode)); + } else { + success = True; + /* Get the data we need to pass to the success function. */ + nb_flags = get_nb_flags(nmb->answers->rdata); + ttl = nmb->answers->ttl; + + /* send off a registration for the next IP, if any */ + wins_next_registration(rrec); + } + } + + DEBUG(5,("register_name_response: %s in registering %sname %s IP %s with %s.\n", + success ? "success" : "failure", + subrec==unicast_subnet?"WINS ":"", + nmb_namestr(answer_name), + reg_name, + inet_ntoa(rrec->packet->ip))); + + if(success) { + /* Enter the registered name into the subnet name database before calling + the success function. */ + standard_success_register(subrec, rrec->userdata, answer_name, nb_flags, ttl, register_ip); + if( rrec->success_fn) + (*(register_name_success_function)rrec->success_fn)(subrec, rrec->userdata, answer_name, nb_flags, ttl, register_ip); + } else { + struct nmb_name qname = *question_name; + if( rrec->fail_fn) + (*(register_name_fail_function)rrec->fail_fn)(subrec, rrec, question_name); + /* Remove the name. */ + standard_fail_register( subrec, &qname); + } + + /* Ensure we don't retry. */ + remove_response_record(subrec, rrec); +} + +/**************************************************************************** + Deal with a timeout of a WINS registration request +****************************************************************************/ + +static void wins_registration_timeout(struct subnet_record *subrec, + struct response_record *rrec) +{ + struct userdata_struct *userdata = rrec->userdata; + struct nmb_packet *sent_nmb = &rrec->packet->packet.nmb; + struct nmb_name *nmbname = &sent_nmb->question.question_name; + struct in_addr register_ip; + fstring src_addr; + + putip(®ister_ip,&sent_nmb->additional->rdata[2]); + + fstrcpy(src_addr, inet_ntoa(register_ip)); + + DEBUG(2,("wins_registration_timeout: WINS server %s timed out registering IP %s\n", + inet_ntoa(rrec->packet->ip), src_addr)); + + /* mark it temporarily dead for this source address */ + wins_srv_died(rrec->packet->ip, register_ip); + + /* if we have some userdata then use that to work out what + wins server to try next */ + if (userdata) { + const char *tag = (const char *)userdata->data; + + /* try the next wins server in our failover list for + this tag */ + rrec->packet->ip = wins_srv_ip_tag(tag, register_ip); + } + + /* if we have run out of wins servers for this tag then they + must all have timed out. We treat this as *success*, not + failure, and go into our standard name refresh mode. This + copes with all the wins servers being down */ + if (wins_srv_is_dead(rrec->packet->ip, register_ip)) { + uint16_t nb_flags = get_nb_flags(sent_nmb->additional->rdata); + int ttl = sent_nmb->additional->ttl; + + standard_success_register(subrec, userdata, nmbname, nb_flags, ttl, register_ip); + if(rrec->success_fn) { + (*(register_name_success_function)rrec->success_fn)(subrec, + rrec->userdata, + nmbname, + nb_flags, + ttl, + register_ip); + } + + /* send off a registration for the next IP, if any */ + wins_next_registration(rrec); + + /* don't need to send this packet any more */ + remove_response_record(subrec, rrec); + return; + } + + /* we will be moving to the next WINS server for this group, + send it immediately */ + rrec->repeat_count = 2; + rrec->repeat_time = time(NULL) + 1; + rrec->in_expiration_processing = False; + + DEBUG(6,("Retrying register of name %s IP %s with WINS server %s\n", + nmb_namestr(nmbname), src_addr, inet_ntoa(rrec->packet->ip))); + + /* notice that we don't remove the response record. This keeps + us trying to register with each of our failover wins servers */ +} + +/**************************************************************************** + Deal with a timeout when registering one of our names. +****************************************************************************/ + +static void register_name_timeout_response(struct subnet_record *subrec, + struct response_record *rrec) +{ + /* + * If we are registering unicast, then NOT getting a response is an + * error - we do not have the name. If we are registering broadcast, + * then we don't expect to get a response. + */ + + struct nmb_packet *sent_nmb = &rrec->packet->packet.nmb; + bool bcast = sent_nmb->header.nm_flags.bcast; + bool success = False; + struct nmb_name *question_name = &sent_nmb->question.question_name; + uint16_t nb_flags = 0; + int ttl = 0; + struct in_addr registered_ip; + + if (bcast) { + if(rrec->num_msgs == 0) { + /* Not receiving a message is success for broadcast registration. */ + success = True; + + /* Pull the success values from the original request packet. */ + nb_flags = get_nb_flags(sent_nmb->additional->rdata); + ttl = sent_nmb->additional->ttl; + putip(®istered_ip,&sent_nmb->additional->rdata[2]); + } + } else { + /* wins timeouts are special */ + wins_registration_timeout(subrec, rrec); + return; + } + + DEBUG(5,("register_name_timeout_response: %s in registering name %s on subnet %s.\n", + success ? "success" : "failure", nmb_namestr(question_name), subrec->subnet_name)); + if(success) { + /* Enter the registered name into the subnet name database before calling + the success function. */ + standard_success_register(subrec, rrec->userdata, question_name, nb_flags, ttl, registered_ip); + if( rrec->success_fn) + (*(register_name_success_function)rrec->success_fn)(subrec, rrec->userdata, question_name, nb_flags, ttl, registered_ip); + } else { + struct nmb_name qname = *question_name; + if( rrec->fail_fn) + (*(register_name_fail_function)rrec->fail_fn)(subrec, rrec, question_name); + /* Remove the name. */ + standard_fail_register( subrec, &qname); + } + + /* Ensure we don't retry. */ + remove_response_record(subrec, rrec); +} + +/**************************************************************************** + Initiate one multi-homed name registration packet. +****************************************************************************/ + +static void multihomed_register_one(struct nmb_name *nmbname, + uint16_t nb_flags, + register_name_success_function success_fn, + register_name_fail_function fail_fn, + struct in_addr ip, + const char *tag) +{ + struct userdata_struct *userdata; + struct in_addr wins_ip = wins_srv_ip_tag(tag, ip); + fstring ip_str; + + userdata = (struct userdata_struct *)SMB_MALLOC(sizeof(*userdata) + strlen(tag) + 1); + if (!userdata) { + DEBUG(0,("Failed to allocate userdata structure!\n")); + return; + } + ZERO_STRUCTP(userdata); + userdata->userdata_len = strlen(tag) + 1; + strlcpy(userdata->data, tag, userdata->userdata_len); + + fstrcpy(ip_str, inet_ntoa(ip)); + + DEBUG(6,("Registering name %s IP %s with WINS server %s using tag '%s'\n", + nmb_namestr(nmbname), ip_str, inet_ntoa(wins_ip), tag)); + + if (queue_register_multihomed_name(unicast_subnet, + register_name_response, + register_name_timeout_response, + success_fn, + fail_fn, + userdata, + nmbname, + nb_flags, + ip, + wins_ip) == NULL) { + DEBUG(0,("multihomed_register_one: Failed to send packet trying to register name %s IP %s\n", + nmb_namestr(nmbname), inet_ntoa(ip))); + } + + free(userdata); +} + +/**************************************************************************** + We have finished the registration of one IP and need to see if we have + any more IPs left to register with this group of wins server for this name. +****************************************************************************/ + +static void wins_next_registration(struct response_record *rrec) +{ + struct nmb_packet *sent_nmb = &rrec->packet->packet.nmb; + struct nmb_name *nmbname = &sent_nmb->question.question_name; + uint16_t nb_flags = get_nb_flags(sent_nmb->additional->rdata); + struct userdata_struct *userdata = rrec->userdata; + const char *tag; + struct in_addr last_ip; + struct subnet_record *subrec; + + putip(&last_ip,&sent_nmb->additional->rdata[2]); + + if (!userdata) { + /* it wasn't multi-homed */ + return; + } + + tag = (const char *)userdata->data; + + for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec)) { + if (ip_equal_v4(last_ip, subrec->myip)) { + subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec); + break; + } + } + + if (!subrec) { + /* no more to do! */ + return; + } + + switch (sent_nmb->header.opcode) { + case NMB_NAME_MULTIHOMED_REG_OPCODE: + multihomed_register_one(nmbname, nb_flags, NULL, NULL, subrec->myip, tag); + break; + case NMB_NAME_REFRESH_OPCODE_8: + queue_wins_refresh(nmbname, + register_name_response, + register_name_timeout_response, + nb_flags, subrec->myip, tag); + break; + } +} + +/**************************************************************************** + Try and register one of our names on the unicast subnet - multihomed. +****************************************************************************/ + +static void multihomed_register_name(struct nmb_name *nmbname, uint16_t nb_flags, + register_name_success_function success_fn, + register_name_fail_function fail_fn) +{ + /* + If we are adding a group name, we just send multiple + register name packets to the WINS server (this is an + internet group name. + + If we are adding a unique name, We need first to add + our names to the unicast subnet namelist. This is + because when a WINS server receives a multihomed + registration request, the first thing it does is to + send a name query to the registering machine, to see + if it has put the name in it's local namelist. + We need the name there so the query response code in + nmbd_incomingrequests.c will find it. + + We are adding this name prematurely (we don't really + have it yet), but as this is on the unicast subnet + only we will get away with this (only the WINS server + will ever query names from us on this subnet). + */ + int num_ips=0; + int i, t; + struct subnet_record *subrec; + char **wins_tags; + struct in_addr *ip_list; + unstring name; + + for(subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec) ) + num_ips++; + + if((ip_list = SMB_MALLOC_ARRAY(struct in_addr, num_ips))==NULL) { + DEBUG(0,("multihomed_register_name: malloc fail !\n")); + return; + } + + for (subrec = FIRST_SUBNET, i = 0; + subrec; + subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec), i++ ) { + ip_list[i] = subrec->myip; + } + + pull_ascii_nstring(name, sizeof(name), nmbname->name); + add_name_to_subnet(unicast_subnet, name, nmbname->name_type, + nb_flags, lp_max_ttl(), SELF_NAME, + num_ips, ip_list); + + /* get the list of wins tags - we try to register for each of them */ + wins_tags = wins_srv_tags(); + + /* Now try and register the name for each wins tag. Note that + at this point we only register our first IP with each wins + group. We will register the rest from + wins_next_registration() when we get the reply for this + one. That follows the way W2K does things (tridge) + */ + for (t=0; wins_tags && wins_tags[t]; t++) { + multihomed_register_one(nmbname, nb_flags, + success_fn, fail_fn, + ip_list[0], + wins_tags[t]); + } + + wins_srv_tags_free(wins_tags); + + SAFE_FREE(ip_list); +} + +/**************************************************************************** + Try and register one of our names. +****************************************************************************/ + +void register_name(struct subnet_record *subrec, + const char *name, int type, uint16_t nb_flags, + register_name_success_function success_fn, + register_name_fail_function fail_fn, + struct userdata_struct *userdata) +{ + struct nmb_name nmbname; + nstring nname; + size_t converted_size; + + errno = 0; + converted_size = push_ascii_nstring(nname, name); + if (converted_size != (size_t)-1) { + /* Success. */ + make_nmb_name(&nmbname, name, type); + } else if (errno == E2BIG) { + /* + * Name converted to CH_DOS is too large. + * try to truncate. + */ + char *converted_str_dos = NULL; + char *converted_str_unix = NULL; + bool ok; + + converted_size = 0; + + ok = convert_string_talloc(talloc_tos(), + CH_UNIX, + CH_DOS, + name, + strlen(name)+1, + &converted_str_dos, + &converted_size); + if (!ok) { + DEBUG(0,("register_name: NetBIOS name %s cannot be " + "converted. Failing to register name.\n", + name)); + return; + } + + /* + * As it's now CH_DOS codepage + * we truncate by writing '\0' at + * MAX_NETBIOSNAME_LEN-1 and then + * convert back to CH_UNIX which we + * need for the make_nmb_name() call. + */ + if (converted_size >= MAX_NETBIOSNAME_LEN) { + converted_str_dos[MAX_NETBIOSNAME_LEN-1] = '\0'; + } + + ok = convert_string_talloc(talloc_tos(), + CH_DOS, + CH_UNIX, + converted_str_dos, + strlen(converted_str_dos)+1, + &converted_str_unix, + &converted_size); + if (!ok) { + DEBUG(0,("register_name: NetBIOS name %s cannot be " + "converted back to CH_UNIX. " + "Failing to register name.\n", + converted_str_dos)); + TALLOC_FREE(converted_str_dos); + return; + } + + make_nmb_name(&nmbname, converted_str_unix, type); + + TALLOC_FREE(converted_str_dos); + TALLOC_FREE(converted_str_unix); + } else { + /* + * Generic conversion error. Fail to register. + */ + DEBUG(0,("register_name: NetBIOS name %s cannot be " + "converted (%s). Failing to register name.\n", + name, strerror(errno))); + return; + } + + /* Always set the NB_ACTIVE flag on the name we are + registering. Doesn't make sense without it. + */ + + nb_flags |= NB_ACTIVE; + + if (subrec == unicast_subnet) { + /* we now always do multi-homed registration if we are + registering to a WINS server. This copes much + better with complex WINS setups */ + multihomed_register_name(&nmbname, nb_flags, + success_fn, fail_fn); + return; + } + + if (queue_register_name(subrec, + register_name_response, + register_name_timeout_response, + success_fn, + fail_fn, + userdata, + &nmbname, + nb_flags) == NULL) { + DEBUG(0,("register_name: Failed to send packet trying to register name %s\n", + nmb_namestr(&nmbname))); + } +} + +/**************************************************************************** + Try and refresh one of our names. This is *only* called for WINS refresh +****************************************************************************/ + +void wins_refresh_name(struct name_record *namerec) +{ + int t; + char **wins_tags; + + /* get the list of wins tags - we try to refresh for each of them */ + wins_tags = wins_srv_tags(); + + for (t=0; wins_tags && wins_tags[t]; t++) { + queue_wins_refresh(&namerec->name, + register_name_response, + register_name_timeout_response, + namerec->data.nb_flags, + namerec->data.ip[0], wins_tags[t]); + } + + wins_srv_tags_free(wins_tags); +} |