/* Unix SMB/CIFS implementation. session handling for utmp and PAM Copyright (C) tridge@samba.org 2001 Copyright (C) abartlet@samba.org 2001 Copyright (C) Gerald (Jerry) Carter 2006 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/>. */ /* a "session" is claimed when we do a SessionSetupX operation and is yielded when the corresponding vuid is destroyed. sessions are used to populate utmp and PAM session structures */ #include "includes.h" /******************************************************************** ********************************************************************/ static struct db_context *session_db_ctx(void) { static struct db_context *ctx; if (ctx) return ctx; ctx = db_open(NULL, lock_path("sessionid.tdb"), 0, TDB_CLEAR_IF_FIRST|TDB_DEFAULT, O_RDWR | O_CREAT, 0644); return ctx; } bool session_init(void) { if (session_db_ctx() == NULL) { DEBUG(1,("session_init: failed to open sessionid tdb\n")); return False; } return True; } /******************************************************************** called when a session is created ********************************************************************/ bool session_claim(user_struct *vuser) { TDB_DATA key, data; int i = 0; struct sessionid sessionid; struct server_id pid = procid_self(); fstring keystr; const char * hostname; struct db_context *ctx; struct db_record *rec; NTSTATUS status; char addr[INET6_ADDRSTRLEN]; vuser->session_keystr = NULL; /* don't register sessions for the guest user - its just too expensive to go through pam session code for browsing etc */ if (vuser->guest) { return True; } if (!(ctx = session_db_ctx())) { return False; } ZERO_STRUCT(sessionid); data.dptr = NULL; data.dsize = 0; if (lp_utmp()) { for (i=1;i<MAX_SESSION_ID;i++) { /* * This is very inefficient and needs fixing -- vl */ struct server_id sess_pid; snprintf(keystr, sizeof(keystr), "ID/%d", i); key = string_term_tdb_data(keystr); rec = ctx->fetch_locked(ctx, NULL, key); if (rec == NULL) { DEBUG(1, ("Could not lock \"%s\"\n", keystr)); return False; } if (rec->value.dsize != sizeof(sessionid)) { DEBUG(1, ("Re-using invalid record\n")); break; } sess_pid = ((struct sessionid *)rec->value.dptr)->pid; if (!process_exists(sess_pid)) { DEBUG(5, ("%s has died -- re-using session\n", procid_str_static(&sess_pid))); break; } TALLOC_FREE(rec); } if (i == MAX_SESSION_ID) { SMB_ASSERT(rec == NULL); DEBUG(1,("session_claim: out of session IDs " "(max is %d)\n", MAX_SESSION_ID)); return False; } snprintf(sessionid.id_str, sizeof(sessionid.id_str), SESSION_UTMP_TEMPLATE, i); } else { snprintf(keystr, sizeof(keystr), "ID/%s/%u", procid_str_static(&pid), vuser->vuid); key = string_term_tdb_data(keystr); rec = ctx->fetch_locked(ctx, NULL, key); if (rec == NULL) { DEBUG(1, ("Could not lock \"%s\"\n", keystr)); return False; } snprintf(sessionid.id_str, sizeof(sessionid.id_str), SESSION_TEMPLATE, (long unsigned int)sys_getpid(), vuser->vuid); } SMB_ASSERT(rec != NULL); /* If 'hostname lookup' == yes, then do the DNS lookup. This is needed because utmp and PAM both expect DNS names client_name() handles this case internally. */ hostname = client_name(get_client_fd()); if (strcmp(hostname, "UNKNOWN") == 0) { hostname = client_addr(get_client_fd(),addr,sizeof(addr)); } fstrcpy(sessionid.username, vuser->user.unix_name); fstrcpy(sessionid.hostname, hostname); sessionid.id_num = i; /* Only valid for utmp sessions */ sessionid.pid = pid; sessionid.uid = vuser->uid; sessionid.gid = vuser->gid; fstrcpy(sessionid.remote_machine, get_remote_machine_name()); fstrcpy(sessionid.ip_addr_str, client_addr(get_client_fd(),addr,sizeof(addr))); sessionid.connect_start = time(NULL); if (!smb_pam_claim_session(sessionid.username, sessionid.id_str, sessionid.hostname)) { DEBUG(1,("pam_session rejected the session for %s [%s]\n", sessionid.username, sessionid.id_str)); TALLOC_FREE(rec); return False; } data.dptr = (uint8 *)&sessionid; data.dsize = sizeof(sessionid); status = rec->store(rec, data, TDB_REPLACE); TALLOC_FREE(rec); if (!NT_STATUS_IS_OK(status)) { DEBUG(1,("session_claim: unable to create session id " "record: %s\n", nt_errstr(status))); return False; } if (lp_utmp()) { sys_utmp_claim(sessionid.username, sessionid.hostname, sessionid.ip_addr_str, sessionid.id_str, sessionid.id_num); } vuser->session_keystr = talloc_strdup(vuser, keystr); if (!vuser->session_keystr) { DEBUG(0, ("session_claim: talloc_strdup() failed for session_keystr\n")); return False; } return True; } /******************************************************************** called when a session is destroyed ********************************************************************/ void session_yield(user_struct *vuser) { TDB_DATA key; struct sessionid sessionid; struct db_context *ctx; struct db_record *rec; if (!(ctx = session_db_ctx())) return; if (!vuser->session_keystr) { return; } key = string_term_tdb_data(vuser->session_keystr); if (!(rec = ctx->fetch_locked(ctx, NULL, key))) { return; } if (rec->value.dsize != sizeof(sessionid)) return; memcpy(&sessionid, rec->value.dptr, sizeof(sessionid)); if (lp_utmp()) { sys_utmp_yield(sessionid.username, sessionid.hostname, sessionid.ip_addr_str, sessionid.id_str, sessionid.id_num); } smb_pam_close_session(sessionid.username, sessionid.id_str, sessionid.hostname); rec->delete_rec(rec); TALLOC_FREE(rec); } /******************************************************************** ********************************************************************/ static bool session_traverse(int (*fn)(struct db_record *db, void *private_data), void *private_data) { struct db_context *ctx; if (!(ctx = session_db_ctx())) { DEBUG(3, ("No tdb opened\n")); return False; } ctx->traverse_read(ctx, fn, private_data); return True; } /******************************************************************** ********************************************************************/ struct session_list { TALLOC_CTX *mem_ctx; int count; struct sessionid *sessions; }; static int gather_sessioninfo(struct db_record *rec, void *state) { struct session_list *sesslist = (struct session_list *) state; const struct sessionid *current = (const struct sessionid *) rec->value.dptr; sesslist->sessions = TALLOC_REALLOC_ARRAY( sesslist->mem_ctx, sesslist->sessions, struct sessionid, sesslist->count+1); if (!sesslist->sessions) { sesslist->count = 0; return -1; } memcpy(&sesslist->sessions[sesslist->count], current, sizeof(struct sessionid)); sesslist->count++; DEBUG(7,("gather_sessioninfo session from %s@%s\n", current->username, current->remote_machine)); return 0; } /******************************************************************** ********************************************************************/ int list_sessions(TALLOC_CTX *mem_ctx, struct sessionid **session_list) { struct session_list sesslist; sesslist.mem_ctx = mem_ctx; sesslist.count = 0; sesslist.sessions = NULL; if (!session_traverse(gather_sessioninfo, (void *) &sesslist)) { DEBUG(3, ("Session traverse failed\n")); SAFE_FREE(sesslist.sessions); *session_list = NULL; return 0; } *session_list = sesslist.sessions; return sesslist.count; }