diff options
Diffstat (limited to 'source4/smbd/password.c')
| -rw-r--r-- | source4/smbd/password.c | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/source4/smbd/password.c b/source4/smbd/password.c new file mode 100644 index 0000000000..d2559ac41e --- /dev/null +++ b/source4/smbd/password.c @@ -0,0 +1,492 @@ +/* + 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" + + +/**************************************************************************** +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(struct server_context *smb, uint16 vuid) +{ + user_struct *usp; + int count=0; + + if (vuid == UID_FIELD_INVALID) + return NULL; + + for (usp=smb->users.validated_users;usp;usp=usp->next,count++) { + if (vuid == usp->vuid) { + if (count > 10) { + DLIST_PROMOTE(smb->users.validated_users, usp); + } + return usp; + } + } + + return NULL; +} + +/**************************************************************************** +invalidate a uid +****************************************************************************/ +void invalidate_vuid(struct server_context *smb, uint16 vuid) +{ + user_struct *vuser = get_valid_user_struct(smb, vuid); + + if (vuser == NULL) + return; + + SAFE_FREE(vuser->homedir); + SAFE_FREE(vuser->unix_homedir); + SAFE_FREE(vuser->logon_script); + + session_yield(vuser); + + free_server_info(&vuser->server_info); + + DLIST_REMOVE(smb->users.validated_users, vuser); + + /* clear the vuid from the 'cache' on each connection, and + from the vuid 'owner' of connections */ + /* REWRITE: conn_clear_vuid_cache(smb, vuid); */ + + SAFE_FREE(vuser->groups); + delete_nt_token(&vuser->nt_user_token); + SAFE_FREE(vuser); + smb->users.num_validated_vuids--; +} + +/**************************************************************************** +invalidate all vuid entries for this process +****************************************************************************/ +void invalidate_all_vuids(struct server_context *smb) +{ + user_struct *usp, *next=NULL; + + for (usp=smb->users.validated_users;usp;usp=next) { + next = usp->next; + + invalidate_vuid(smb, 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) + * + * @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(struct server_context *smb, + struct auth_serversupplied_info *server_info, + const char *smb_name) +{ + user_struct *vuser = NULL; + + /* Ensure no vuid gets registered in share level security. */ + if(lp_security() == SEC_SHARE) + return UID_FIELD_INVALID; + + /* Limit allowed vuids to 16bits - VUID_OFFSET. */ + if (smb->users.num_validated_vuids >= 0xFFFF-VUID_OFFSET) + return UID_FIELD_INVALID; + + if((vuser = (user_struct *)malloc( sizeof(user_struct) )) == NULL) { + DEBUG(0,("Failed to malloc users struct!\n")); + return UID_FIELD_INVALID; + } + + ZERO_STRUCTP(vuser); + + /* Allocate a free vuid. Yes this is a linear search... :-) */ + while (get_valid_user_struct(smb, smb->users.next_vuid) != NULL ) { + smb->users.next_vuid++; + /* Check for vuid wrap. */ + if (smb->users.next_vuid == UID_FIELD_INVALID) + smb->users.next_vuid = VUID_OFFSET; + } + + DEBUG(10,("register_vuid: allocated vuid = %u\n", + (unsigned int)smb->users.next_vuid)); + + vuser->vuid = smb->users.next_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 + */ + if (!IS_SAM_UNIX_USER(server_info->sam_account)) { + DEBUG(0,("Attempted session setup with invalid user. No uid/gid in SAM_ACCOUNT\n")); + free(vuser); + free_server_info(&server_info); + return UID_FIELD_INVALID; + } + + vuser->uid = pdb_get_uid(server_info->sam_account); + vuser->gid = pdb_get_gid(server_info->sam_account); + + vuser->n_groups = server_info->n_groups; + if (vuser->n_groups) { + if (!(vuser->groups = memdup(server_info->groups, sizeof(gid_t) * vuser->n_groups))) { + DEBUG(0,("register_vuid: failed to memdup vuser->groups\n")); + free(vuser); + free_server_info(&server_info); + return UID_FIELD_INVALID; + } + } + + vuser->guest = server_info->guest; + fstrcpy(vuser->user.unix_name, pdb_get_username(server_info->sam_account)); + + /* 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 *unix_homedir = pdb_get_unix_homedir(server_info->sam_account); + const char *logon_script = pdb_get_logon_script(server_info->sam_account); + if (homedir) { + vuser->homedir = smb_xstrdup(homedir); + } + + if (unix_homedir) { + vuser->unix_homedir = smb_xstrdup(unix_homedir); + } + + if (logon_script) { + vuser->logon_script = smb_xstrdup(logon_script); + } + } + + memcpy(vuser->session_key, server_info->session_key, sizeof(vuser->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(server_info->ptok); + } else { + DEBUG(1, ("server_info does not contain a user_token - cannot continue\n")); + free_server_info(&server_info); + 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)); + + smb->users.next_vuid++; + smb->users.num_validated_vuids++; + + DLIST_ADD(smb->users.validated_users, vuser); + + if (!session_claim(smb, vuser)) { + DEBUG(1,("Failed to claim session for vuid=%d\n", vuser->vuid)); + invalidate_vuid(smb, vuser->vuid); + return -1; + } + + /* Register a home dir service for this user */ + if ((!vuser->guest) && vuser->unix_homedir && *(vuser->unix_homedir)) { + DEBUG(3, ("Adding/updating homes service for user '%s' using home direcotry: '%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 { + vuser->homes_snum = -1; + } + + return vuser->vuid; +} + + +/**************************************************************************** +add a name to the session users list +****************************************************************************/ +void add_session_user(struct server_context *smb, const char *user) +{ + char *suser; + struct passwd *passwd; + + if (!(passwd = Get_Pwnam(user))) return; + + suser = strdup(passwd->pw_name); + if (!suser) { + return; + } + + if (suser && *suser && !in_list(suser,smb->users.session_users,False)) { + char *p; + if (!smb->users.session_users) { + asprintf(&p, "%s", suser); + } else { + asprintf(&p, "%s %s", smb->users.session_users, suser); + } + SAFE_FREE(smb->users.session_users); + smb->users.session_users = p; + } + + free(suser); +} + + +/**************************************************************************** +check if a username is valid +****************************************************************************/ +BOOL user_ok(const char *user,int snum, gid_t *groups, size_t n_groups) +{ + 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))) { + ret = !user_in_list(user, (const char **)invalid, groups, n_groups); + } + } + 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))) { + ret = user_in_list(user, (const char **)valid, groups, n_groups); + } + } + 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, groups, n_groups); + } + if (user_list) str_list_free (&user_list); + } + + return(ret); +} + +/**************************************************************************** +validate a group username entry. Return the username or NULL +****************************************************************************/ +static const char *validate_group(struct server_context *smb, const 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, NULL, 0) && + password_ok(smb, 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) { + const char *name = member; + if (user_ok(name,snum, NULL, 0) && + password_ok(smb,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(struct server_context *smb, + int snum, const char *user, DATA_BLOB password, + BOOL *guest) +{ + BOOL ok = False; + +#if 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 = strdup(smb->users.session_users); + if (!user_list) + return(False); + + for (auser=strtok(user_list,LIST_SEP); !ok && auser; + auser = strtok(NULL,LIST_SEP)) { + const char *user2 = auser; + + if (!user_ok(user2,snum, NULL, 0)) + continue; + + if (password_ok(smb, user2,password)) { + ok = True; + DEBUG(3,("authorise_login: ACCEPTED: session list username (%s) \ +and given password ok\n", user2)); + } + } + + SAFE_FREE(user_list); + } + + /* check the user= fields and the given password */ + if (!ok && lp_username(snum)) { + const char *auser; + pstring user_list; + StrnCpy(user_list,lp_username(snum),sizeof(pstring)); + + 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(smb, auser+1,password,snum); + if (auser) { + ok = True; + DEBUG(3,("authorise_login: ACCEPTED: group username \ +and given password ok (%s)\n", auser)); + } + } else { + const char *user2 = auser; + if (user_ok(user2,snum, NULL, 0) && password_ok(smb, user2,password)) { + ok = True; + DEBUG(3,("authorise_login: ACCEPTED: user list username \ +and given password ok (%s)\n", user2)); + } + } + } + } + + /* check for a normal guest connection */ + if (!ok && GUEST_OK(snum)) { + const char *guestname = lp_guestaccount(); + if (Get_Pwnam(guestname)) { + ok = True; + DEBUG(3,("authorise_login: ACCEPTED: guest account and guest ok (%s)\n", guestname)); + } else { + DEBUG(0,("authorise_login: Invalid guest account %s??\n",guestname)); + } + *guest = True; + } + + if (ok && !user_ok(user, snum, NULL, 0)) { + DEBUG(0,("authorise_login: rejected invalid user %s\n",user)); + ok = False; + } + + return(ok); +} |