/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2007 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define SMB_SERVER_SIGNATURE 0xaa550415 /* * Macro definitions: */ static char *lanman = MAILSLOT_LANMAN; static char *browse = MAILSLOT_BROWSE; typedef struct server_info { uint32_t type; uint32_t signature; char major; char minor; char hostname[NETBIOS_NAME_SZ]; char comment[SMB_PI_MAX_COMMENT]; char update_count; struct name_entry name; } server_info_t; #define BROWSER_NF_INVALID 0x00 #define BROWSER_NF_VALID 0x01 typedef struct browser_netinfo { uint32_t flags; int next_announce; int reps; int interval; server_info_t server; mutex_t mtx; } browser_netinfo_t; /* * Local Data Definitions: */ static struct browser_netinfo smb_browser_info[SMB_PI_MAX_NETWORKS]; static void smb_browser_init(void); static inline browser_netinfo_t * smb_browser_getnet(int net) { browser_netinfo_t *subnet; if (net < smb_nic_get_num()) { subnet = &smb_browser_info[net]; (void) mutex_lock(&subnet->mtx); if (subnet->flags & BROWSER_NF_VALID) return (subnet); } return (0); } static inline void smb_browser_putnet(browser_netinfo_t *netinfo) { if (netinfo) (void) mutex_unlock(&netinfo->mtx); } /* * 3. Browser Overview * * Hosts involved in the browsing process can be separated into two * distinct groups, browser clients and browser servers (often referred to * simply as "browsers"). * * A browser is a server which maintains information about servers - * primarily the domain they are in and the services that they are running * -- and about domains. Browsers may assume several different roles in * their lifetimes, and dynamically switch between them. * * Browser clients are of two types: workstations and (non-browser) * servers. In the context of browsing, workstations query browsers for the * information they contain; servers supply browsers the information by * registering with them. Note that, at times, browsers may themselves * behave as browser clients and query other browsers. * * For the purposes of this specification, a domain is simply a name with * which to associate a group of resources such as computers, servers and * users. Domains allow a convenient means for browser clients to restrict * the scope of a search when they query browser servers. Every domain has * a "master" server called the Primary Domain Controller (PDC) that * manages various activities within the domain. * * One browser for each domain on a subnet is designated the Local Master * Browser for that domain. Servers in its domain on the subnet register * with it, as do the Local Master Browsers for other domains on the * subnet. It uses these registrations to maintain authoritative * information about its domain on its subnet. If there are other subnets * in the network, it also knows the name of the server running the * domain's Domain Master Browser; it registers with it, and uses it to * obtain information about the rest of the network (see below). * * Clients on a subnet query browsers designated as the Backup Browsers for * the subnet (not the Master Browser). Backup Browsers maintain a copy of * the information on the Local Master Browser; they get it by periodically * querying the Local Master Browser for all of its information. Clients * find the Backup Browsers by asking the Local Master Browser. Clients are * expected to spread their queries evenly across Backup Browsers to * balance the load. * * The Local Master Browser is dynamically elected automatically. Multiple * Backup Browser Servers may exist per subnet; they are selected from * among the potential browser servers by the Local Master Browser, which * is configured to select enough to handle the expected query load. * * When there are multiple subnets, a Domain Master Browser is assigned * the task of keeping the multiple subnets in synchronization. The Primary * Domain Controller (PDC) always acts as the Domain Master Browser. The * Domain Master Browser periodically acts as a client and queries all the * Local Master Browsers for its domain, asking them for a list containing * all the domains and all the servers in their domain known within their * subnets; it merges all the replies into a single master list. This * allows a Domain Master Browser server to act as a collection point for * inter-subnet browsing information. Local Master Browsers periodically * query the Domain Master Browser to retrieve the network-wide information * it maintains. * * When a domain spans only a single subnet, there will not be any distinct * Local Master Browser; this role will be handled by the Domain Master * Browser. Similarly, the Domain Master Browser is always the Local Master * Browser for the subnet it is on. * * When a browser client suspects that the Local Master Browser has failed, * the client will instigate an election in which the browser servers * participate, and some browser servers may change roles. * * Some characteristics of a good browsing mechanism include: * . minimal network traffic * . minimum server discovery time * . minimum change discovery latency * . immunity to machine failures * * Historically, Browser implementations had been very closely tied to * NETBIOS and datagrams. The early implementations caused a lot of * broadcast traffic. See Appendix D for an overview that presents how the * Browser specification evolved. * * 4. Browsing Protocol Architecture * * This section first describes the how the browsing protocol is layered, * then describes the roles of clients, servers, and browsers in the * browsing subsystem. * * 4.1 Layering of Browsing Protocol Requests * * Most of the browser functionality is implemented using mailslots. * Mailslots provide a mechanism for fast, unreliable unidirectional data * transfer; they are named via ASCII "mailslot (path) name". Mailslots are * implemented using the CIFS Transact SMB which is encapsulated in a * NETBIOS datagram. Browser protocol requests are sent to browser specific * mailslots using some browser-specific NETBIOS names. These datagrams can * either be unicast or broadcast, depending on whether the NETBIOS name is * a "unique name" or a "group name". Various data structures, which are * detailed subsequently within this document, flow as the data portion of * the Transact SMB. * * Here is an example of a generic browser SMB, showing how a browser * request is encapsulated in a TRANSACT SMB request. Note that the PID, * TID, MID, UID, and Flags are all 0 in mailslot requests. * * SMB: C transact, File = \MAILSLOT\BROWSE * SMB: SMB Status = Error Success * SMB: Error class = No Error * SMB: Error code = No Error * SMB: Header: PID = 0x0000 TID = 0x0000 MID = 0x0000 UID = 0x0000 * SMB: Tree ID (TID) = 0 (0x0) * SMB: Process ID (PID) = 0 (0x0) * SMB: User ID (UID) = 0 (0x0) * SMB: Multiplex ID (MID) = 0 (0x0) * SMB: Flags Summary = 0 (0x0) * SMB: Command = C transact * SMB: Word count = 17 * SMB: Word parameters * SMB: Total parm bytes = 0 * SMB: Total data bytes = 33 * SMB: Max parm bytes = 0 * SMB: Max data bytes = 0 * SMB: Max setup words = 0 * SMB: Transact Flags Summary = 0 (0x0) * SMB: ...............0 = Leave session intact * SMB: ..............0. = Response required * SMB: Transact timeout = 0 (0x0) * SMB: Parameter bytes = 0 (0x0) * SMB: Parameter offset = 0 (0x0) * SMB: Data bytes = 33 (0x21) * SMB: Data offset = 86 (0x56) * SMB: Setup word count = 3 * SMB: Setup words * SMB: Mailslot opcode = Write mailslot * SMB: Transaction priority = 1 * SMB: Mailslot class = Unreliable (broadcast) * SMB: Byte count = 50 * SMB: Byte parameters * SMB: Path name = \MAILSLOT\BROWSE * SMB: Transaction data * SMB: Data: Number of data bytes remaining = 33 (0x0021) * * Note the SMB command is Transact, the opcode within the Transact SMB is * Mailslot Write, and the browser data structure is carried as the * Transact data. * The Transaction data begins with an opcode, that signifies the operation * and determines the size and structure of data that follows. This opcode * is named as per one of the below: * * HostAnnouncement 1 * AnnouncementRequest 2 * RequestElection 8 * GetBackupListReq 9 * GetBackupListResp 10 * BecomeBackup 11 * DomainAnnouncment 12 * MasterAnnouncement 13 * LocalMasterAnnouncement 15 * * Browser datagrams are often referred to as simply browser frames. The * frames are in particular, referred to by the name of the opcode within * the Transaction data e.g. a GetBackupListReq browser frame, a * RequestElection browser frame, etc. * * The structures that are sent as the data portion of the Transact SMB are * described in section(s) 6.2 through 6.12 in this document. These * structures are tightly packed, i.e. there are no intervening pad bytes * in the structure, unless they are explicitly described as being there. * All quantities are sent in native Intel format and multi-byte values are * transmitted least significant byte first. * * Besides mailslots and Transaction SMBs, the other important piece of the * browser architecture is the NetServerEnum2 request. This request that * allows an application to interrogate a Browser Server and obtain a * complete list of resources (servers, domains, etc) known to that Browser * server. Details of the NetServerEnum2 request are presented in section * 6.4. Some examples of the NetServerEnum2 request being used are when a * Local Master Browser sends a NetServerEnum2 request to the Domain Master * Browser and vice versa. Another example is when a browser client sends a * NetServerEnum2 request to a Backup Browser server. * * 4.3 Non-Browser Server * * A non-browser server is a server that has some resource(s) or service(s) * it wishes to advertise as being available using the browsing protocol. * Examples of non-browser servers would be an SQL server, print server, * etc. * * A non-browser server MUST periodically send a HostAnnouncement browser * frame, specifying the type of resources or services it is advertising. * Details are in section 6.5. * * A non-browser server SHOULD announce itself relatively frequently when * it first starts up in order to make its presence quickly known to the * browsers and thence to potential clients. The frequency of the * announcements SHOULD then be gradually stretched, so as to minimize * network traffic. Typically, non-browser servers announce themselves * once every minute upon start up and then gradually adjust the frequency * of the announcements to once every 12 minutes. * * A non-browser server SHOULD send a HostAnnouncement browser frame * specifying a type of 0 just prior to shutting down, to allow it to * quickly be removed from the list of available servers. * * A non-browser server MUST receive and process AnnouncementRequest frames * from the Local Master Browser, and MUST respond with a HostAnnouncement * frame, after a delay chosen randomly from the interval [0,30] seconds. * AnnouncementRequests typically happen when a Local Master Browser starts * up with an empty list of servers for the domain, and wants to fill it * quickly. The 30 second range for responses prevents the Master Browser * from becoming overloaded and losing replies, as well as preventing the * network from being flooded with responses. * * 4.4 Browser Servers * * The following sections describe the roles of the various types of * browser servers. * * 4.4.1 Potential Browser Server * * A Potential Browser server is a browser server that is capable of being * a Backup Browser server or Master Browser server, but is not currently * fulfilling either of those roles. * * A Potential Browser MUST set type SV_TYPE_POTENTIAL_BROWSER (see section * 6.4.1) in its HostAnnouncement until it is ready to shut down. In its * last HostAnnouncement frame before it shuts down, it SHOULD specify a * type of 0. * * A Potential Browser server MUST receive and process BecomeBackup frames * (see section 6.9) and become a backup browser upon their receipt. * * A Potential Browser MUST participate in browser elections (see section * 6.8). * * 4.4.2 Backup Browser * * Backup Browser servers are a subset of the Potential Browsers that have * been chosen by the Master Browser on their subnet to be the Backup * Browsers for the subnet. * * A Backup Browser MUST set type SV_TYPE_BACKUP_BROWSER (see section * 6.4.1) in its HostAnnouncement until it is ready to shut down. In its * last HostAnnouncement frame before it shuts down, it SHOULD specify a * type of 0. * * A Backup Browser MUST listen for a LocalMasterAnnouncement frame (see * section 6.10) from the Local Master Browser, and use it to set the name * of the Master Browser it queries for the server and domain lists. * * A Backup Browsers MUST periodically make a NetServerEnum2 request of * the Master Browser on its subnet for its domain to get a list of servers * in that domain, as well as a list of domains. The period is a * configuration option balancing currency of the information with network * traffic costs - a typical value is 15 minutes. * * A Backup Browser SHOULD force an election by sending a RequestElection * frame (see section 6.7) if it does not get a response to its periodic * NetServeEnum2 request to the Master Browser. * * A Backup Browser MUST receive and process NetServerEnum2 requests from * browser clients, for its own domain and others. If the request is for a * list of servers in its domain, or for a list of domains, it can answer * from its internal lists. If the request is for a list of servers in a * domain different than the one it serves, it sends a NetServerEnum2 * request to the Domain Master Browser for that domain (which it can in * find in its list of domains and their Domain Master Browsers). * * A Backup Browser MUST participate in browser elections (see section * 6.8). * * 4.4.3 Master Browser * * Master Browsers are responsible for: * . indicating it is a Master Browser * . receiving server announcements and building a list of such servers * and keeping it reasonably up-to-date. * . returning lists of Backup Browsers to browser clients. * . ensuring an appropriate number of Backup Browsers are available. * . announcing their existence to other Master Browsers on their subnet, * to the Domain Master Browser for their domain, and to all browsers in * their domain on their subnet * . forwarding requests for lists of servers on other domains to the * Master Browser for that domain * . keeping a list of domains in its subnet * . synchronizing with the Domain Master Browser (if any) for its domain * . participating in browser elections * . ensuring that there is only one Master Browser on its subnet * * A Master Browser MUST set type SV_TYPE_MASTER_BROWSER (see section * 6.4.1) in its HostAnnouncement until it is ready to shut down. In its * last HostAnnouncement frame before it shuts down, it SHOULD specify a * type of 0. * * A Master Browser MUST receive and process HostAnnouncement frames from * servers, adding the server name and other information to its servers * list; it must mark them as "local" entries. Periodically, it MUST check * all local server entries to see if a server's HostAnnouncement has timed * out (no HostAnnouncement received for three times the periodicity the * server gave in the last received HostAnnouncement) and remove timed-out * servers from its list. * * A Master Browser MUST receive and process DomainAnnouncement frames (see * section 6.12) and maintain the domain names and their associated (Local) * Master Browsers in its internal domain list until they time out; it must * mark these as "local" entries. Periodically, it MUST check all local * domain entries to see if a server's DomainAnnouncement has timed out (no * DomainAnnouncement received for three times the periodicity the server * gave in the last received DomainAnnouncement) and remove timed-out * servers from its list. * * A Master Browser MUST receive and process GetBackupListRequest frames * from clients, returning GetBackupListResponse frames containing a list * of the Backup Servers for its domain. * * A Master Browser MUST eventually send BecomeBackup frames (see section * 6.9) to one or more Potential Browser servers to increase the number of * Backup Browsers if there are not enough Backup Browsers to handle the * anticipated query load. Note: possible good times for checking for * sufficient backup browsers are after being elected, when timing out * server HostAnnouncements, and when receiving a server's HostAnnouncement * for the first time. * * A Master Browser MUST periodically announce itself and the domain it * serves to other (Local) Master Browsers on its subnet, by sending a * DomainAnnouncement frame (see section 6.12) to its subnet. * * A Master Browser MUST send a MasterAnnouncement frame (see section 6.11) * to the Domain Master Browser after it is first elected, and periodically * thereafter. This informs the Domain Master Browser of the presence of * all the Master Browsers. * * A Master Browser MUST periodically announce itself to all browsers for * its domain on its subnet by sending a LocalMasterAnnouncement frame (see * section 6.10). * * A Master Browser MUST receive and process NetServerEnum2 requests from * browser clients, for its own domain and others. If the request is for a * list of servers in its domain, or for a list of domains, it can answer * from its internal lists. Entries in its list marked "local" MUST have * the SV_TYPE_LOCAL_LIST_ONLY bit set in the returned results; it must be * clear for all other entries. If the request is for a list of servers in * a domain different than the one it serves, it sends a NetServerEnum2 * request to the Domain Master Browser for that domain (which it can in * find in its list of domains and their Domain Master Browsers). * * Note: The list of servers that the Master Browser maintains and * returns to the Backup Browsers, is limited in size to 64K of * data. This will limit the number of systems that can be in a * browse list in a single workgroup or domain to approximately two * thousand systems. * * A Master Browser SHOULD request all servers to register with it by * sending an AnnouncementRequest frame, if, on becoming the Master Browser * by winning an election, its server list is empty. Otherwise, clients * might get an incomplete list of servers until the servers' periodic * registrations fill the server list. * * If the Master Browser on a subnet is not the Primary Domain Controller * (PDC), then it is a Local Master Browser. * * A Local Master Browser MUST periodically synchronize with the Domain * Master Browser (which is the PDC). This synchronization is performed by * making a NetServerEnum2 request to the Domain Master Browser and merging * the results with its list of servers and domains. An entry from the * Domain Master Browser should be marked "non-local", and must not * overwrite an entry with the same name marked "local". The Domain Master * Browser is located as specified in Appendix B. * * A Master Browser MUST participate in browser elections (see section * 6.8). * * A Master Browser MUST, if it receives a HostAnnouncement, * DomainAnnouncement, or LocalMasterAnnouncement frame another system that * claims to be the Master Browser for its domain, demote itself from * Master Browser and force an election. This ensures that there is only * ever one Master Browser in each workgroup or domain. * * A Master Browser SHOULD, if it loses an election, become a Backup * Browser (without being told to do so by the new Master Browser). Since * it has more up-to-date information in its lists than a Potential * Browser, it is more efficient to have it be a Backup Browser than to * promote a Potential Browser. * * 4.4.3.1 Preferred Master Browser * * A Preferred Master Browser supports exactly the same protocol elements * as a Potential Browser, except as follows. * * A Preferred Master Browser MUST always force an election when it starts * up. * * A Preferred Master Browser MUST participate in browser elections (see * section 6.8). * * A Preferred Master Browser MUST set the Preferred Master bit in the * RequestElection frame (see section 6.7) to bias the election in its * favor. * * A Preferred Master Browser SHOULD, if it loses an election, * automatically become a Backup Browser, without being told to do so by * the Master Browser. * * 4.4.4 Domain Master Browser * * Since the Domain Master Browser always runs on the PDC, it must * implement all the protocols required of a PDC in addition to the * browsing protocol, and that is way beyond the scope of this * specification. * * 5. Mailslot Protocol Specification * * The only transaction allowed to a mailslot is a mailslot write. Mailslot * writes requests are encapsulated in TRANSACT SMBs. The following table * shows the interpretation of the TRANSACT SMB parameters for a mailslot * transaction: * * Name Value Description * Command SMB_COM_TRANSACTION * Name STRING name of mail slot to write; * must start with "\\MAILSLOT\\" * SetupCount 3 Always 3 for mailslot writes * Setup[0] 1 Command code == write mailslot * Setup[1] Ignored * Setup[2] Ignored * TotalDataCount n Size of data in bytes to write to * the mailslot * Data[ n ] The data to write to the mailslot * */ /* * SMB: C transact, File = \MAILSLOT\BROWSE * SMB: SMB Status = Error Success * SMB: Error class = No Error * SMB: Error code = No Error * SMB: Header: PID = 0x0000 TID = 0x0000 MID = 0x0000 UID = 0x0000 * SMB: Tree ID (TID) = 0 (0x0) * SMB: Process ID (PID) = 0 (0x0) * SMB: User ID (UID) = 0 (0x0) * SMB: Multiplex ID (MID) = 0 (0x0) * SMB: Flags Summary = 0 (0x0) * SMB: Command = C transact * SMB: Word count = 17 * SMB: Word parameters * SMB: Total parm bytes = 0 * SMB: Total data bytes = 33 * SMB: Max parm bytes = 0 * SMB: Max data bytes = 0 * SMB: Max setup words = 0 * SMB: Transact Flags Summary = 0 (0x0) * SMB: ...............0 = Leave session intact * SMB: ..............0. = Response required * SMB: Transact timeout = 0 (0x0) * SMB: Parameter bytes = 0 (0x0) * SMB: Parameter offset = 0 (0x0) * SMB: Data bytes = 33 (0x21) * SMB: Data offset = 86 (0x56) * SMB: Setup word count = 3 * SMB: Setup words * SMB: Mailslot opcode = Write mailslot * SMB: Transaction priority = 1 * SMB: Mailslot class = Unreliable (broadcast) * SMB: Byte count = 50 * SMB: Byte parameters * SMB: Path name = \MAILSLOT\BROWSE * SMB: Transaction data * SMB: Data: Number of data bytes remaining = 33 (0x0021) * * 5. Mailslot Protocol Specification * * The only transaction allowed to a mailslot is a mailslot write. Mailslot * writes requests are encapsulated in TRANSACT SMBs. The following table * shows the interpretation of the TRANSACT SMB parameters for a mailslot * transaction: * * Name Value Description * Command SMB_COM_TRANSACTION * Name STRING name of mail slot to write; * must start with "\MAILSLOT\" * SetupCount 3 Always 3 for mailslot writes * Setup[0] 1 Command code == write mailslot * Setup[1] Ignored * Setup[2] Ignored * TotalDataCount n Size of data in bytes to write to * the mailslot * Data[ n ] The data to write to the mailslot * * Magic 0xFF 'S' 'M' 'B' * smb_com a byte, the "first" command * Error a 4-byte union, ignored in a request * smb_flg a one byte set of eight flags * smb_flg2 a two byte set of 16 flags * . twelve reserved bytes, have a role * in connectionless transports (IPX, UDP?) * smb_tid a 16-bit tree ID, a mount point sorta, * 0xFFFF is this command does not have * or require a tree context * smb_pid a 16-bit process ID * smb_uid a 16-bit user ID, specific to this "session" * and mapped to a system (bona-fide) UID * smb_mid a 16-bit multiplex ID, used to differentiate * multiple simultaneous requests from the same * process (pid) (ref RPC "xid") */ int smb_browser_load_transact_header(unsigned char *buffer, int maxcnt, int data_count, int reply, char *mailbox) { smb_msgbuf_t mb; int mailboxlen; char *fmt; int result; short class = (reply == ONE_WAY_TRANSACTION) ? 2 : 0; /* * If the mailboxlen is an even number we need to pad the * header so that the data starts on a word boundary. */ fmt = "Mb4.bw20.bwwwwb.wl2.wwwwb.wwwws"; mailboxlen = strlen(mailbox) + 1; if ((mailboxlen & 0x01) == 0) { ++mailboxlen; fmt = "Mb4.bw20.bwwwwb.wl2.wwwwb.wwwws."; } bzero(buffer, maxcnt); smb_msgbuf_init(&mb, buffer, maxcnt, 0); result = smb_msgbuf_encode(&mb, fmt, SMB_COM_TRANSACTION, /* Command */ 0x18, 0x3, 17, /* Count of parameter words */ 0, /* Total Parameter words sent */ data_count, /* Total Data bytes sent */ 2, /* Max Parameters to return */ 0, /* Max data bytes to return */ 0, /* Max setup bytes to return */ reply, /* No reply */ 0xffffffff, /* Timeout */ 0, /* Parameter bytes sent */ 0, /* Parameter offset */ data_count, /* Data bytes sent */ 69 + mailboxlen, /* Data offset */ 3, /* Setup word count */ 1, /* Setup word[0] */ 0, /* Setup word[1] */ class, /* Setup word[2] */ mailboxlen + data_count, /* Total request bytes */ mailbox); /* Mailbox address */ smb_msgbuf_term(&mb); return (result); } /* * smb_net_id * * Lookup for the given IP in the NICs info table. * If it finds a matching entry it'll return the index, * otherwise returns -1. * * SMB network table and SMB browser info table share * the same index. */ int smb_net_id(uint32_t ipaddr) { uint32_t myaddr, mask; int net, smb_nc_cnt; smb_nc_cnt = smb_nic_get_num(); for (net = 0; net < smb_nc_cnt; net++) { net_cfg_t cfg; if (smb_nic_get_byind(net, &cfg) == NULL) break; mask = cfg.mask; myaddr = cfg.ip; if ((ipaddr & mask) == (myaddr & mask)) return (net); } return (-1); } /* * smb_browser_get_srvname * */ struct name_entry * smb_browser_get_srvname(unsigned short netid) { if (netid < smb_nic_get_num()) return (&(smb_browser_info[netid].server.name)); return (NULL); } static int smb_browser_addr_of_subnet(struct name_entry *name, int subnet, struct name_entry *result) { uint32_t ipaddr, mask, saddr; struct addr_entry *addr; int smb_nc_cnt; net_cfg_t cfg; smb_nc_cnt = smb_nic_get_num(); if ((name == 0) || subnet >= smb_nc_cnt) return (-1); if (smb_nic_get_byind(subnet, &cfg) == NULL) return (-1); ipaddr = cfg.ip; mask = cfg.mask; *result = *name; addr = &name->addr_list; do { saddr = addr->sin.sin_addr.s_addr; if ((saddr & mask) == (ipaddr & mask)) { *result = *name; result->addr_list = *addr; result->addr_list.forw = result->addr_list.back = &result->addr_list; return (0); } addr = addr->forw; } while (addr != &name->addr_list); return (-1); } static int smb_browser_bcast_addr_of_subnet(struct name_entry *name, int net, struct name_entry *result) { uint32_t broadcast; int smb_nc_cnt; net_cfg_t cfg; smb_nc_cnt = smb_nic_get_num(); if (net >= smb_nc_cnt) return (-1); if (name != 0 && name != result) *result = *name; if (smb_nic_get_byind(net, &cfg) == NULL) return (-1); broadcast = cfg.broadcast; result->addr_list.sin.sin_family = AF_INET; result->addr_list.sinlen = sizeof (result->addr_list.sin); result->addr_list.sin.sin_addr.s_addr = broadcast; result->addr_list.sin.sin_port = htons(DGM_SRVC_UDP_PORT); result->addr_list.forw = result->addr_list.back = &result->addr_list; return (0); } /* * 6.5 HostAnnouncement Browser Frame * * To advertise its presence, i.e. to publish itself as being available, a * non-browser server sends a HostAnnouncement browser frame. If the server * is a member of domain "D", this frame is sent to the NETBIOS unique name * D(1d) and mailslot "\\MAILSLOT\\BROWSE". The definition of the * HostAnnouncement frame is: * * struct { * unsigned short Opcode; * unsigned char UpdateCount; * uint32_t Periodicity; * unsigned char ServerName[]; * unsigned char VersionMajor; * unsigned char VersionMinor; * uint32_t Type; * uint32_t Signature; * unsigned char Comment[]; * } * * where: * Opcode - Identifies this structure as a browser server * announcement and is defined as HostAnnouncement with a * value of decimal 1. * * UpdateCount - must be sent as zero and ignored on receipt. * * Periodicity - The announcement frequency of the server (in * seconds). The server will be removed from the browse list * if it has not been heard from in 3X its announcement * frequency. In no case will the server be removed from the * browse list before the period 3X has elapsed. Actual * implementations may take more than 3X to actually remove * the server from the browse list. * * ServerName - Null terminated ASCII server name (up to 16 bytes * in length). * * VersionMajor - The major version number of the OS the server * is running. it will be returned by NetServerEnum2. * * VersionMinor - The minor version number of the OS the server * is running. This is entirely informational and does not * have any significance for the browsing protocol. * * Type - Specifies the type of the server. The server type bits * are specified in the NetServerEnum2 section. * * Signature - The browser protocol minor version number in the * low 8 bits, the browser protocol major version number in * the next higher 8 bits and the signature 0xaa55 in the * high 16 bits of this field. Thus, for this version of the * browser protocol (1.15) this field has the value * 0xaa55010f. This may used to isolate browser servers that * are running out of revision browser software; otherwise, * it is ignored. * * Comment - Null terminated ASCII comment for the server. * Limited to 43 bytes. * * When a non-browser server starts up, it announces itself in the manner * described once every minute. The frequency of these statements is * gradually stretched to once every 12 minutes. * * Note: older non-browser servers in a domain "D" sent HostAnnouncement * frames to the NETBIOS group name D(00). Non-Browser servers supporting * version 1.15 of the browsing protocol SHOULD NOT use this NETBIOS name, * but for backwards compatibility Master Browsers MAY receive and process * HostAnnouncement frames on this name as described above for D(1d). */ void smb_browser_send_HostAnnouncement(int net, int32_t next_announcement, struct addr_entry *addr, char suffix) { smb_msgbuf_t mb; int offset, announce_len, data_length; struct name_entry dest_name; struct name_entry server_name; struct browser_netinfo *subnet; server_info_t *server; unsigned char *buffer; uint32_t type; char resource_domain[SMB_PI_MAX_DOMAIN]; syslog(LOG_DEBUG, "smb_browse: send_HostAnnouncement(%d)", net); smb_config_rdlock(); (void) strlcpy(resource_domain, smb_config_getstr(SMB_CI_DOMAIN_NAME), SMB_PI_MAX_DOMAIN); (void) utf8_strupr(resource_domain); smb_config_unlock(); if (addr == 0) { /* Local master Browser */ smb_init_name_struct( (unsigned char *)resource_domain, suffix, 0, 0, 0, 0, 0, &dest_name); if (smb_browser_bcast_addr_of_subnet(0, net, &dest_name) < 0) return; } else { smb_init_name_struct( (unsigned char *)resource_domain, suffix, 0, 0, 0, 0, 0, &dest_name); dest_name.addr_list = *addr; dest_name.addr_list.forw = dest_name.addr_list.back = &dest_name.addr_list; } /* give some extra room */ buffer = (unsigned char *)malloc(MAX_DATAGRAM_LENGTH * 2); if (buffer == 0) { syslog(LOG_ERR, "HostAnnouncement: resource shortage"); return; } subnet = smb_browser_getnet(net); if (subnet == 0) { free(buffer); return; } server = &subnet->server; data_length = 1 + 1 + 4 + 16 + 1 + 1 + 4 + 4 + strlen(server->comment) + 1; if ((offset = smb_browser_load_transact_header(buffer, MAX_DATAGRAM_LENGTH, data_length, ONE_WAY_TRANSACTION, browse)) < 0) { smb_browser_putnet(subnet); free(buffer); return; } /* * A non-browser server SHOULD send a HostAnnouncement browser frame * specifying a type of 0 just prior to shutting down, to allow it to * quickly be removed from the list of available servers. */ type = (nb_status.state & NETBIOS_SHUTTING_DOWN) ? 0 : server->type; smb_msgbuf_init(&mb, buffer + offset, MAX_DATAGRAM_LENGTH - offset, 0); announce_len = smb_msgbuf_encode(&mb, "bbl16cbblls", (char)HOST_ANNOUNCEMENT, /* Announcement opcode */ (char)++subnet->server.update_count, next_announcement * 60000, /* Periodicity in MilliSeconds */ server->hostname, /* Server name */ server->major, /* our major version */ server->minor, /* our minor version */ type, /* server type */ server->signature, /* Signature */ server->comment); /* Let 'em know */ server_name = server->name; smb_browser_putnet(subnet); if (announce_len > 0) (void) smb_netbios_datagram_send(&server_name, &dest_name, buffer, offset + announce_len); free(buffer); smb_msgbuf_term(&mb); } void smb_browser_process_AnnouncementRequest(struct datagram *datagram, char *mailbox) { struct browser_netinfo *subnet; unsigned int next_announcement; uint32_t delay = random() % 29; /* in seconds */ int net; if (strcmp(mailbox, lanman) != 0) { syslog(LOG_DEBUG, "smb_browse: Wrong Mailbox (%s)", mailbox); return; } net = smb_net_id(datagram->src.addr_list.sin.sin_addr.s_addr); if (net < 0) { /* We don't know who this is so ignore it... */ return; } (void) sleep(delay); subnet = smb_browser_getnet(net); if (subnet) { next_announcement = subnet->next_announce * 60 * 1000; smb_browser_putnet(subnet); smb_browser_send_HostAnnouncement(net, next_announcement, &datagram->src.addr_list, 0x1D); } } void * smb_browser_dispatch(void *arg) { struct datagram *datagram = (struct datagram *)arg; smb_msgbuf_t mb; int rc; unsigned char command; unsigned char parameter_words; unsigned short total_parameter_words; unsigned short total_data_count; unsigned short max_parameters_to_return; unsigned short max_data_to_return; unsigned char max_setup_bytes_to_return; unsigned short reply; unsigned short parameter_bytes_sent; unsigned short parameter_offset; unsigned short data_bytes_sent; unsigned short data_offset; unsigned char setup_word_count; unsigned short setup_word_0; unsigned short setup_word_1; unsigned short setup_word_2; unsigned short total_request_bytes; char *mailbox; unsigned char message_type; unsigned char *data; int datalen; syslog(LOG_DEBUG, "smb_browse: packet_received"); smb_msgbuf_init(&mb, datagram->data, datagram->data_length, 0); rc = smb_msgbuf_decode(&mb, "Mb27.bwwwwb.w6.wwwwb.wwwws", &command, /* Command */ ¶meter_words, /* Count of parameter words */ &total_parameter_words, /* Total Parameter words sent */ &total_data_count, /* Total Data bytes sent */ &max_parameters_to_return, /* Max Parameters to return */ &max_data_to_return, /* Max data bytes to return */ &max_setup_bytes_to_return, /* Max setup bytes to return */ &reply, /* No reply */ ¶meter_bytes_sent, /* Parameter bytes sent */ ¶meter_offset, /* Parameter offset */ &data_bytes_sent, /* Data bytes sent */ &data_offset, /* Data offset */ &setup_word_count, /* Setup word count */ &setup_word_0, /* Setup word[0] */ &setup_word_1, /* Setup word[1] */ &setup_word_2, /* Setup word[2] */ &total_request_bytes, /* Total request bytes */ &mailbox); /* Mailbox address */ if (rc < 0) { syslog(LOG_ERR, "smb_browser_dispatch: decode error"); smb_msgbuf_term(&mb); free(datagram); return (0); } data = &datagram->data[data_offset]; datalen = datagram->data_length - data_offset; /* * The PDC location protocol, i.e. anything on the \\NET * mailslot, is handled by the smb_netlogon module. */ if (strncasecmp("\\MAILSLOT\\NET\\", mailbox, 14) == 0) { smb_netlogon_receive(datagram, mailbox, data, datalen); smb_msgbuf_term(&mb); free(datagram); return (0); } /* * If it's not a netlogon message, assume it's a browser request. * This is not the most elegant way to extract the command byte * but at least we no longer use it to get the netlogon opcode. */ message_type = datagram->data[data_offset]; switch (message_type) { case ANNOUNCEMENT_REQUEST : smb_browser_process_AnnouncementRequest(datagram, mailbox); break; default: syslog(LOG_DEBUG, "smb_browse: invalid message_type(%d, %x)", message_type, message_type); break; } smb_msgbuf_term(&mb); free(datagram); return (0); } /* * 11.1 Registered unique names * * (00) * This name is used by all servers and clients to receive second * class mailslot messages. A system must add this name in order to * receive mailslot messages. The only browser requests that should * appear on this name are BecomeBackup, GetBackupListResp, * MasterAnnouncement, and LocalMasterAnnouncement frames. All other * datagrams (other than the expected non-browser datagrams) may be * ignored and an error logged. * * (1d) * This name is used to identify a master browser server for domain * "DOMAIN" on a subnet. A master browser server adds this name as a * unique NETBIOS name when it becomes master browser. If the attempt * to add the name fails, the master browser server assumes that there * is another master in the domain and will fail to come up. It may * log an error if the failure occurs more than 3 times in a row (this * either indicates some form of network misconfiguration or a * software error). The only requests that should appear on this name * are GetBackupListRequest and HostAnnouncement requests. All other * datagrams on this name may be ignored (and an error logged). If * running a NETBIOS name service (NBNS, such as WINS), this name * should not be registered with the NBNS. * * (1b) * This name is used to identify the Domain Master Browser for domain * "DOMAIN" (which is also the primary domain controller). It is a * unique name added only by the primary domain controller. The * primary domain controller will respond to GetBackupListRequest on * this name just as it responds to these requests on the (1d) * name. * * 11.2 Registered group names * * (01)(02)__MSBROWSE__(02)(01) * This name is used by Master Browsers to announce themselves to the * other Master Browsers on a subnet. It is added as a group name by * all Master Browser servers. The only broadcasts that should appear * on this name is DomainAnnouncement requests. All other datagrams * can be ignored. * * (00) * This name is used by clients and servers in domain "DOMAIN" to * process server announcements. The only requests that should appear * on this name that the browser is interested in are * AnnouncementRequest and NETLOGON_QUERY (to locate the PDC) packets. * All other unidentifiable requests may be ignored (and an error * logged). * * (1E) * This name is used for announcements to browsers for domain "DOMAIN" * on a subnet. This name is registered by all the browser servers in * the domain. The only requests that should appear on this name are * RequestElection and AnnouncementRequest packets. All other * datagrams may be ignored (and an error logged). * * (1C) * This name is registered by Primary Domain Controllers. */ void smb_browser_config(void) { struct name_entry name; struct name_entry master; struct name_entry dest; struct name_entry *entry; int smb_nc_cnt; net_cfg_t cfg; int net; char resource_domain[SMB_PI_MAX_DOMAIN]; syslog(LOG_DEBUG, "smb_browse: reconfigure"); smb_browser_init(); smb_config_rdlock(); (void) strlcpy(resource_domain, smb_config_getstr(SMB_CI_DOMAIN_NAME), SMB_PI_MAX_DOMAIN); (void) utf8_strupr(resource_domain); smb_config_unlock(); /* domain<00> */ smb_init_name_struct((unsigned char *)resource_domain, 0x00, 0, 0, 0, 0, 0, &name); entry = smb_name_find_name(&name); smb_name_unlock_name(entry); smb_nc_cnt = smb_nic_get_num(); for (net = 0; net < smb_nc_cnt; net++) { if (smb_nic_get_byind(net, &cfg) == NULL) break; if (cfg.exclude) continue; smb_init_name_struct( (unsigned char *)resource_domain, 0x00, 0, cfg.ip, htons(DGM_SRVC_UDP_PORT), NAME_ATTR_GROUP, NAME_ATTR_LOCAL, &name); (void) smb_name_add_name(&name); } /* All our local master browsers */ smb_init_name_struct((unsigned char *)resource_domain, 0x1D, 0, 0, 0, 0, 0, &dest); entry = smb_name_find_name(&dest); if (entry) { for (net = 0; net < smb_nc_cnt; net++) { if (smb_browser_addr_of_subnet(entry, net, &master) == 0) { syslog(LOG_DEBUG, "smbd: Master browser found at %s", inet_ntoa(master.addr_list.sin.sin_addr)); } } smb_name_unlock_name(entry); } smb_init_name_struct((unsigned char *)resource_domain, 0x1B, 0, 0, 0, 0, 0, &dest); if ((entry = smb_name_find_name(&dest)) != 0) { syslog(LOG_DEBUG, "smbd: Domain Master browser for %s is %s", resource_domain, inet_ntoa(entry->addr_list.sin.sin_addr)); smb_name_unlock_name(entry); } } static void smb_browser_init() { struct browser_netinfo *subnet; struct server_info *server; char cmnt[SMB_PI_MAX_COMMENT], hostname[MAXHOSTNAMELEN]; int i, j; int smb_nc_cnt; net_cfg_t cfg; (void) smb_gethostname(hostname, MAXHOSTNAMELEN, 1); smb_config_rdlock(); (void) strlcpy(cmnt, smb_config_getstr(SMB_CI_SYS_CMNT), sizeof (cmnt)); smb_config_unlock(); smb_nc_cnt = smb_nic_get_num(); for (i = 0; i < smb_nc_cnt; i++) { if (smb_nic_get_byind(i, &cfg) == NULL) break; if (cfg.exclude) continue; subnet = &smb_browser_info[i]; (void) mutex_lock(&subnet->mtx); /* One Minute announcements for first five */ subnet->flags = BROWSER_NF_VALID; subnet->next_announce = 1; subnet->interval = 1; subnet->reps = 5; server = &subnet->server; bzero(server, sizeof (struct server_info)); server->type = MY_SERVER_TYPE; server->major = SMB_VERSION_MAJOR; server->minor = SMB_VERSION_MINOR; server->signature = SMB_SERVER_SIGNATURE; (void) strlcpy(server->comment, cmnt, SMB_PI_MAX_COMMENT); (void) snprintf(server->hostname, NETBIOS_NAME_SZ, "%.15s", hostname); /* * 00 is workstation service. * 20 is file server service. */ smb_init_name_struct((unsigned char *)server->hostname, 0x20, 0, cfg.ip, htons(DGM_SRVC_UDP_PORT), NAME_ATTR_UNIQUE, NAME_ATTR_LOCAL, &server->name); (void) mutex_unlock(&subnet->mtx); } /* Invalidate unconfigured NICs */ for (j = i; j < SMB_PI_MAX_NETWORKS; j++) { subnet = &smb_browser_info[j]; (void) mutex_lock(&subnet->mtx); subnet->flags = BROWSER_NF_INVALID; (void) mutex_unlock(&subnet->mtx); } } /* * smb_browser_non_master_duties * * To advertise its presence, i.e. to publish itself as being available, a * non-browser server sends a HostAnnouncement browser frame. If the server * is a member of domain "D", this frame is sent to the NETBIOS unique name * D(1d) and mailslot "\\MAILSLOT\\BROWSE". */ void smb_browser_non_master_duties(int net) { struct browser_netinfo *subnet; struct name_entry name; struct name_entry *dest; struct addr_entry addr; int interval; char resource_domain[SMB_PI_MAX_DOMAIN]; subnet = smb_browser_getnet(net); if (subnet == 0) return; interval = subnet->interval; smb_browser_putnet(subnet); smb_browser_send_HostAnnouncement(net, interval, 0, 0x1D); smb_config_rdlock(); (void) strlcpy(resource_domain, smb_config_getstr(SMB_CI_DOMAIN_NAME), SMB_PI_MAX_DOMAIN); (void) utf8_strupr(resource_domain); smb_config_unlock(); smb_init_name_struct((unsigned char *)resource_domain, 0x1D, 0, 0, 0, 0, 0, &name); if ((dest = smb_name_find_name(&name))) { addr = dest->addr_list; addr.forw = addr.back = &addr; smb_name_unlock_name(dest); smb_browser_send_HostAnnouncement(net, interval, &addr, 0x1D); } else { smb_init_name_struct( (unsigned char *)resource_domain, 0x1B, 0, 0, 0, 0, 0, &name); if ((dest = smb_name_find_name(&name))) { addr = dest->addr_list; addr.forw = addr.back = &addr; smb_name_unlock_name(dest); smb_browser_send_HostAnnouncement(net, interval, &addr, 0x1B); } } subnet = smb_browser_getnet(net); /* * One Minute announcements for first five * minutes, one munute longer each round * until 12 minutes and every 12 minutes * thereafter. */ if (--subnet->reps == 0) { if (subnet->interval < 12) subnet->interval++; subnet->reps = 1; } subnet->next_announce = subnet->interval; smb_browser_putnet(subnet); } /* * browser_sleep * * Put browser in 1 minute sleep if netbios services are not * shutting down and both name and datagram services are still * running. It'll wake up after 1 minute or if one of the above * conditions go false. It checks the conditions again and return * 1 if everything is ok or 0 if browser shouldn't continue * running. */ static int browser_sleep() { int slept = 0; timestruc_t to; (void) mutex_lock(&nb_status.mtx); while (((nb_status.state & NETBIOS_SHUTTING_DOWN) == 0) && (nb_status.state & NETBIOS_NAME_SVC_RUNNING) && (nb_status.state & NETBIOS_DATAGRAM_SVC_RUNNING)) { if (slept) { (void) mutex_unlock(&nb_status.mtx); return (1); } to.tv_sec = 60; /* 1 minute */ to.tv_nsec = 0; (void) cond_reltimedwait(&nb_status.cv, &nb_status.mtx, &to); slept = 1; } (void) mutex_unlock(&nb_status.mtx); return (0); } /* * smb_browser_start * * Smb Netbios browser daemon. */ /*ARGSUSED*/ void * smb_browser_daemon(void *arg) { int net; int next_announce; struct browser_netinfo *subnet; int run = 1; int smb_nc_cnt; net_cfg_t cfg; smb_browser_config(); nb_status.state |= NETBIOS_BROWSER_RUNNING; while (run) { smb_nc_cnt = smb_nic_get_num(); for (net = 0; net < smb_nc_cnt; net++) { if (smb_nic_get_byind(net, &cfg) == NULL) break; if (cfg.exclude) continue; subnet = smb_browser_getnet(net); next_announce = --subnet->next_announce; smb_browser_putnet(subnet); if (next_announce > 0 || cfg.broadcast == 0) continue; smb_browser_non_master_duties(net); } run = browser_sleep(); } smb_netbios_chg_status(NETBIOS_BROWSER_RUNNING, 0); return (0); }