/* Unix SMB/CIFS implementation. Password and authentication handling Copyright (C) Andrew Tridgell 1992-1998 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. */ #include "includes.h" /* users from session setup */ static char *session_userlist = NULL; static int len_session_userlist = 0; /* this holds info on user ids that are already validated for this VC */ static user_struct *validated_users; static int next_vuid = VUID_OFFSET; static int num_validated_vuids; extern userdom_struct current_user_info; /**************************************************************************** Check if a uid has been validated, and return an pointer to the user_struct if it has. NULL if not. vuid is biased by an offset. This allows us to tell random client vuid's (normally zero) from valid vuids. ****************************************************************************/ user_struct *get_valid_user_struct(uint16 vuid) { user_struct *usp; int count=0; if (vuid == UID_FIELD_INVALID) return NULL; for (usp=validated_users;usp;usp=usp->next,count++) { if (vuid == usp->vuid && usp->server_info) { if (count > 10) { DLIST_PROMOTE(validated_users, usp); } return usp; } } return NULL; } /**************************************************************************** Get the user struct of a partial NTLMSSP login ****************************************************************************/ user_struct *get_partial_auth_user_struct(uint16 vuid) { user_struct *usp; int count=0; if (vuid == UID_FIELD_INVALID) return NULL; for (usp=validated_users;usp;usp=usp->next,count++) { if (vuid == usp->vuid && !usp->server_info) { if (count > 10) { DLIST_PROMOTE(validated_users, usp); } return usp; } } return NULL; } /**************************************************************************** Invalidate a uid. ****************************************************************************/ void invalidate_vuid(uint16 vuid) { user_struct *vuser = get_valid_user_struct(vuid); if (vuser == NULL) return; SAFE_FREE(vuser->homedir); SAFE_FREE(vuser->unix_homedir); SAFE_FREE(vuser->logon_script); session_yield(vuser); SAFE_FREE(vuser->session_keystr); TALLOC_FREE(vuser->server_info); data_blob_free(&vuser->session_key); DLIST_REMOVE(validated_users, vuser); /* clear the vuid from the 'cache' on each connection, and from the vuid 'owner' of connections */ conn_clear_vuid_cache(vuid); SAFE_FREE(vuser->groups); TALLOC_FREE(vuser->nt_user_token); SAFE_FREE(vuser); num_validated_vuids--; } /**************************************************************************** Invalidate all vuid entries for this process. ****************************************************************************/ void invalidate_all_vuids(void) { user_struct *usp, *next=NULL; for (usp=validated_users;usp;usp=next) { next = usp->next; invalidate_vuid(usp->vuid); } } /** * register that a valid login has been performed, establish 'session'. * @param server_info The token returned from the authentication process. * (now 'owned' by register_vuid) * * @param session_key The User session key for the login session (now also * 'owned' by register_vuid) * * @param respose_blob The NT challenge-response, if available. (May be * freed after this call) * * @param smb_name The untranslated name of the user * * @return Newly allocated vuid, biased by an offset. (This allows us to * tell random client vuid's (normally zero) from valid vuids.) * */ int register_vuid(auth_serversupplied_info *server_info, DATA_BLOB session_key, DATA_BLOB response_blob, const char *smb_name) { user_struct *vuser = NULL; /* Ensure no vuid gets registered in share level security. */ if(lp_security() == SEC_SHARE) { data_blob_free(&session_key); return UID_FIELD_INVALID; } /* Limit allowed vuids to 16bits - VUID_OFFSET. */ if (num_validated_vuids >= 0xFFFF-VUID_OFFSET) { data_blob_free(&session_key); return UID_FIELD_INVALID; } if((vuser = SMB_MALLOC_P(user_struct)) == NULL) { DEBUG(0,("Failed to malloc users struct!\n")); data_blob_free(&session_key); return UID_FIELD_INVALID; } ZERO_STRUCTP(vuser); /* Allocate a free vuid. Yes this is a linear search... :-) */ while( get_valid_user_struct(next_vuid) != NULL ) { next_vuid++; /* Check for vuid wrap. */ if (next_vuid == UID_FIELD_INVALID) next_vuid = VUID_OFFSET; } DEBUG(10,("register_vuid: allocated vuid = %u\n", (unsigned int)next_vuid )); vuser->vuid = next_vuid; if (!server_info) { next_vuid++; num_validated_vuids++; vuser->server_info = NULL; DLIST_ADD(validated_users, vuser); return vuser->vuid; } /* the next functions should be done by a SID mapping system (SMS) as * the new real sam db won't have reference to unix uids or gids */ vuser->uid = server_info->uid; vuser->gid = server_info->gid; vuser->n_groups = server_info->n_groups; if (vuser->n_groups) { if (!(vuser->groups = (gid_t *)memdup(server_info->groups, sizeof(gid_t) * vuser->n_groups))) { DEBUG(0,("register_vuid: failed to memdup " "vuser->groups\n")); data_blob_free(&session_key); free(vuser); TALLOC_FREE(server_info); return UID_FIELD_INVALID; } } vuser->guest = server_info->guest; fstrcpy(vuser->user.unix_name, server_info->unix_name); /* This is a potentially untrusted username */ alpha_strcpy(vuser->user.smb_name, smb_name, ". _-$", sizeof(vuser->user.smb_name)); fstrcpy(vuser->user.domain, pdb_get_domain(server_info->sam_account)); fstrcpy(vuser->user.full_name, pdb_get_fullname(server_info->sam_account)); { /* Keep the homedir handy */ const char *homedir = pdb_get_homedir(server_info->sam_account); const char *logon_script = pdb_get_logon_script(server_info->sam_account); if (!IS_SAM_DEFAULT(server_info->sam_account, PDB_UNIXHOMEDIR)) { const char *unix_homedir = pdb_get_unix_homedir(server_info->sam_account); if (unix_homedir) { vuser->unix_homedir = smb_xstrdup(unix_homedir); } } else { struct passwd *passwd = getpwnam_alloc(NULL, vuser->user.unix_name); if (passwd) { vuser->unix_homedir = smb_xstrdup(passwd->pw_dir); TALLOC_FREE(passwd); } } if (homedir) { vuser->homedir = smb_xstrdup(homedir); } if (logon_script) { vuser->logon_script = smb_xstrdup(logon_script); } } vuser->session_key = session_key; DEBUG(10,("register_vuid: (%u,%u) %s %s %s guest=%d\n", (unsigned int)vuser->uid, (unsigned int)vuser->gid, vuser->user.unix_name, vuser->user.smb_name, vuser->user.domain, vuser->guest )); DEBUG(3, ("User name: %s\tReal name: %s\n", vuser->user.unix_name, vuser->user.full_name)); if (server_info->ptok) { vuser->nt_user_token = dup_nt_token(NULL, server_info->ptok); } else { DEBUG(1, ("server_info does not contain a user_token - " "cannot continue\n")); TALLOC_FREE(server_info); data_blob_free(&session_key); SAFE_FREE(vuser->homedir); SAFE_FREE(vuser->unix_homedir); SAFE_FREE(vuser->logon_script); SAFE_FREE(vuser); return UID_FIELD_INVALID; } /* use this to keep tabs on all our info from the authentication */ vuser->server_info = server_info; DEBUG(3,("UNIX uid %d is UNIX user %s, and will be vuid %u\n", (int)vuser->uid,vuser->user.unix_name, vuser->vuid)); next_vuid++; num_validated_vuids++; DLIST_ADD(validated_users, vuser); if (!session_claim(vuser)) { DEBUG(1, ("Failed to claim session for vuid=%d\n", vuser->vuid)); invalidate_vuid(vuser->vuid); return UID_FIELD_INVALID; } /* Register a home dir service for this user iff (a) This is not a guest connection, (b) we have a home directory defined (c) there s not an existing static share by that name If a share exists by this name (autoloaded or not) reuse it . */ vuser->homes_snum = -1; if ( (!vuser->guest) && vuser->unix_homedir && *(vuser->unix_homedir)) { int servicenumber = lp_servicenumber(vuser->user.unix_name); if ( servicenumber == -1 ) { DEBUG(3, ("Adding homes service for user '%s' using " "home directory: '%s'\n", vuser->user.unix_name, vuser->unix_homedir)); vuser->homes_snum = add_home_service(vuser->user.unix_name, vuser->user.unix_name, vuser->unix_homedir); } else { DEBUG(3, ("Using static (or previously created) " "service for user '%s'; path = '%s'\n", vuser->user.unix_name, lp_pathname(servicenumber) )); vuser->homes_snum = servicenumber; } } if (srv_is_signing_negotiated() && !vuser->guest && !srv_signing_started()) { /* Try and turn on server signing on the first non-guest * sessionsetup. */ srv_set_signing(vuser->session_key, response_blob); } /* fill in the current_user_info struct */ set_current_user_info( &vuser->user ); return vuser->vuid; } /**************************************************************************** Add a name to the session users list. ****************************************************************************/ void add_session_user(const char *user) { fstring suser; struct passwd *passwd; if (!(passwd = Get_Pwnam(user))) return; fstrcpy(suser,passwd->pw_name); if(!*suser) return; if( session_userlist && in_list(suser,session_userlist,False) ) return; if( !session_userlist || (strlen(suser) + strlen(session_userlist) + 2 >= len_session_userlist) ) { char *newlist; if (len_session_userlist > 128 * PSTRING_LEN) { DEBUG(3,("add_session_user: session userlist already " "too large.\n")); return; } newlist = (char *)SMB_REALLOC_KEEP_OLD_ON_ERROR( session_userlist, len_session_userlist + PSTRING_LEN ); if( newlist == NULL ) { DEBUG(1,("Unable to resize session_userlist\n")); return; } if (!session_userlist) { *newlist = '\0'; } session_userlist = newlist; len_session_userlist += PSTRING_LEN; } safe_strcat(session_userlist," ",len_session_userlist-1); safe_strcat(session_userlist,suser,len_session_userlist-1); } /**************************************************************************** Check if a user is in a netgroup user list. If at first we don't succeed, try lower case. ****************************************************************************/ BOOL user_in_netgroup(const char *user, const char *ngname) { #ifdef HAVE_NETGROUP static char *mydomain = NULL; fstring lowercase_user; if (mydomain == NULL) yp_get_default_domain(&mydomain); if(mydomain == NULL) { DEBUG(5,("Unable to get default yp domain\n")); return False; } DEBUG(5,("looking for user %s of domain %s in netgroup %s\n", user, mydomain, ngname)); if (innetgr(ngname, NULL, user, mydomain)) { DEBUG(5,("user_in_netgroup: Found\n")); return (True); } else { /* * Ok, innetgr is case sensitive. Try once more with lowercase * just in case. Attempt to fix #703. JRA. */ fstrcpy(lowercase_user, user); strlower_m(lowercase_user); DEBUG(5,("looking for user %s of domain %s in netgroup %s\n", lowercase_user, mydomain, ngname)); if (innetgr(ngname, NULL, lowercase_user, mydomain)) { DEBUG(5,("user_in_netgroup: Found\n")); return (True); } } #endif /* HAVE_NETGROUP */ return False; } /**************************************************************************** Check if a user is in a user list - can check combinations of UNIX and netgroup lists. ****************************************************************************/ BOOL user_in_list(const char *user,const char **list) { if (!list || !*list) return False; DEBUG(10,("user_in_list: checking user %s in list\n", user)); while (*list) { DEBUG(10,("user_in_list: checking user |%s| against |%s|\n", user, *list)); /* * Check raw username. */ if (strequal(user, *list)) return(True); /* * Now check to see if any combination * of UNIX and netgroups has been specified. */ if(**list == '@') { /* * Old behaviour. Check netgroup list * followed by UNIX list. */ if(user_in_netgroup(user, *list +1)) return True; if(user_in_group(user, *list +1)) return True; } else if (**list == '+') { if((*(*list +1)) == '&') { /* * Search UNIX list followed by netgroup. */ if(user_in_group(user, *list +2)) return True; if(user_in_netgroup(user, *list +2)) return True; } else { /* * Just search UNIX list. */ if(user_in_group(user, *list +1)) return True; } } else if (**list == '&') { if(*(*list +1) == '+') { /* * Search netgroup list followed by UNIX list. */ if(user_in_netgroup(user, *list +2)) return True; if(user_in_group(user, *list +2)) return True; } else { /* * Just search netgroup list. */ if(user_in_netgroup(user, *list +1)) return True; } } list++; } return(False); } /**************************************************************************** Check if a username is valid. ****************************************************************************/ static BOOL user_ok(const char *user, int snum) { char **valid, **invalid; BOOL ret; valid = invalid = NULL; ret = True; if (lp_invalid_users(snum)) { str_list_copy(&invalid, lp_invalid_users(snum)); if (invalid && str_list_substitute(invalid, "%S", lp_servicename(snum))) { if ( invalid && str_list_sub_basic(invalid, current_user_info.smb_name) ) { ret = !user_in_list(user, (const char **)invalid); } } } if (invalid) str_list_free (&invalid); if (ret && lp_valid_users(snum)) { str_list_copy(&valid, lp_valid_users(snum)); if ( valid && str_list_substitute(valid, "%S", lp_servicename(snum)) ) { if ( valid && str_list_sub_basic(valid, current_user_info.smb_name) ) { ret = user_in_list(user, (const char **)valid); } } } if (valid) str_list_free (&valid); if (ret && lp_onlyuser(snum)) { char **user_list = str_list_make (lp_username(snum), NULL); if (user_list && str_list_substitute(user_list, "%S", lp_servicename(snum))) { ret = user_in_list(user, (const char **)user_list); } if (user_list) str_list_free (&user_list); } return(ret); } /**************************************************************************** Validate a group username entry. Return the username or NULL. ****************************************************************************/ static char *validate_group(char *group, DATA_BLOB password,int snum) { #ifdef HAVE_NETGROUP { char *host, *user, *domain; setnetgrent(group); while (getnetgrent(&host, &user, &domain)) { if (user) { if (user_ok(user, snum) && password_ok(user,password)) { endnetgrent(); return(user); } } } endnetgrent(); } #endif #ifdef HAVE_GETGRENT { struct group *gptr; setgrent(); while ((gptr = (struct group *)getgrent())) { if (strequal(gptr->gr_name,group)) break; } /* * As user_ok can recurse doing a getgrent(), we must * copy the member list into a pstring on the stack before * use. Bug pointed out by leon@eatworms.swmed.edu. */ if (gptr) { pstring member_list; char *member; size_t copied_len = 0; int i; *member_list = '\0'; member = member_list; for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) { size_t member_len = strlen(gptr->gr_mem[i])+1; if(copied_len+member_len < sizeof(pstring)) { DEBUG(10,("validate_group: = gr_mem = " "%s\n", gptr->gr_mem[i])); safe_strcpy(member, gptr->gr_mem[i], sizeof(pstring) - copied_len - 1); copied_len += member_len; member += copied_len; } else { *member = '\0'; } } endgrent(); member = member_list; while (*member) { static fstring name; fstrcpy(name,member); if (user_ok(name,snum) && password_ok(name,password)) { endgrent(); return(&name[0]); } DEBUG(10,("validate_group = member = %s\n", member)); member += strlen(member) + 1; } } else { endgrent(); return NULL; } } #endif return(NULL); } /**************************************************************************** Check for authority to login to a service with a given username/password. Note this is *NOT* used when logging on using sessionsetup_and_X. ****************************************************************************/ BOOL authorise_login(int snum, fstring user, DATA_BLOB password, BOOL *guest) { BOOL ok = False; #ifdef DEBUG_PASSWORD DEBUG(100,("authorise_login: checking authorisation on " "user=%s pass=%s\n", user,password.data)); #endif *guest = False; /* there are several possibilities: 1) login as the given user with given password 2) login as a previously registered username with the given password 3) login as a session list username with the given password 4) login as a previously validated user/password pair 5) login as the "user =" user with given password 6) login as the "user =" user with no password (guest connection) 7) login as guest user with no password if the service is guest_only then steps 1 to 5 are skipped */ /* now check the list of session users */ if (!ok) { char *auser; char *user_list = NULL; if ( session_userlist ) user_list = SMB_STRDUP(session_userlist); else user_list = SMB_STRDUP(""); if (!user_list) return(False); for (auser=strtok(user_list,LIST_SEP); !ok && auser; auser = strtok(NULL,LIST_SEP)) { fstring user2; fstrcpy(user2,auser); if (!user_ok(user2,snum)) continue; if (password_ok(user2,password)) { ok = True; fstrcpy(user,user2); DEBUG(3,("authorise_login: ACCEPTED: session " "list username (%s) and given " "password ok\n", user)); } } SAFE_FREE(user_list); } /* check the user= fields and the given password */ if (!ok && lp_username(snum)) { char *auser; pstring user_list; pstrcpy(user_list,lp_username(snum)); pstring_sub(user_list,"%S",lp_servicename(snum)); for (auser=strtok(user_list,LIST_SEP); auser && !ok; auser = strtok(NULL,LIST_SEP)) { if (*auser == '@') { auser = validate_group(auser+1,password,snum); if (auser) { ok = True; fstrcpy(user,auser); DEBUG(3,("authorise_login: ACCEPTED: " "group username and given " "password ok (%s)\n", user)); } } else { fstring user2; fstrcpy(user2,auser); if (user_ok(user2,snum) && password_ok(user2,password)) { ok = True; fstrcpy(user,user2); DEBUG(3,("authorise_login: ACCEPTED: " "user list username and " "given password ok (%s)\n", user)); } } } } /* check for a normal guest connection */ if (!ok && GUEST_OK(snum)) { fstring guestname; fstrcpy(guestname,lp_guestaccount()); if (Get_Pwnam(guestname)) { fstrcpy(user,guestname); ok = True; DEBUG(3,("authorise_login: ACCEPTED: guest account " "and guest ok (%s)\n", user)); } else { DEBUG(0,("authorise_login: Invalid guest account " "%s??\n",guestname)); } *guest = True; } if (ok && !user_ok(user, snum)) { DEBUG(0,("authorise_login: rejected invalid user %s\n",user)); ok = False; } return(ok); }