diff options
Diffstat (limited to 'source3/smbd/password.c')
| -rw-r--r-- | source3/smbd/password.c | 829 |
1 files changed, 829 insertions, 0 deletions
diff --git a/source3/smbd/password.c b/source3/smbd/password.c new file mode 100644 index 0000000000..1d3514429f --- /dev/null +++ b/source3/smbd/password.c @@ -0,0 +1,829 @@ +/* + Unix SMB/CIFS implementation. + Password and authentication handling + Copyright (C) Andrew Tridgell 1992-1998 + Copyright (C) Jeremy Allison 2007. + + 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" + +/* users from session setup */ +static char *session_userlist = NULL; +/* workgroup from session setup. */ +static char *session_workgroup = NULL; + +/* 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; + +enum server_allocated_state { SERVER_ALLOCATED_REQUIRED_YES, + SERVER_ALLOCATED_REQUIRED_NO, + SERVER_ALLOCATED_REQUIRED_ANY}; + +static user_struct *get_valid_user_struct_internal(uint16 vuid, + enum server_allocated_state server_allocated) +{ + 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) { + switch (server_allocated) { + case SERVER_ALLOCATED_REQUIRED_YES: + if (usp->server_info == NULL) { + continue; + } + break; + case SERVER_ALLOCATED_REQUIRED_NO: + if (usp->server_info != NULL) { + continue; + } + case SERVER_ALLOCATED_REQUIRED_ANY: + break; + } + if (count > 10) { + DLIST_PROMOTE(validated_users, usp); + } + return usp; + } + } + + return NULL; +} + +/**************************************************************************** + 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) +{ + return get_valid_user_struct_internal(vuid, + SERVER_ALLOCATED_REQUIRED_YES); +} + +bool is_partial_auth_vuid(uint16 vuid) +{ + if (vuid == UID_FIELD_INVALID) { + return False; + } + return get_valid_user_struct_internal(vuid, + SERVER_ALLOCATED_REQUIRED_NO) ? True : False; +} + +/**************************************************************************** + Get the user struct of a partial NTLMSSP login +****************************************************************************/ + +user_struct *get_partial_auth_user_struct(uint16 vuid) +{ + return get_valid_user_struct_internal(vuid, + SERVER_ALLOCATED_REQUIRED_NO); +} + +/**************************************************************************** + Invalidate a uid. +****************************************************************************/ + +void invalidate_vuid(uint16 vuid) +{ + user_struct *vuser = NULL; + + if (vuid == UID_FIELD_INVALID) { + return; + } + + vuser = get_valid_user_struct_internal(vuid, + SERVER_ALLOCATED_REQUIRED_ANY); + if (vuser == NULL) { + return; + } + + session_yield(vuser); + + if (vuser->auth_ntlmssp_state) { + auth_ntlmssp_end(&vuser->auth_ntlmssp_state); + } + + DLIST_REMOVE(validated_users, vuser); + + /* clear the vuid from the 'cache' on each connection, and + from the vuid 'owner' of connections */ + conn_clear_vuid_caches(vuid); + + TALLOC_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); + } +} + +/**************************************************** + Create a new partial auth user struct. +*****************************************************/ + +int register_initial_vuid(void) +{ + user_struct *vuser; + + /* Paranoia check. */ + if(lp_security() == SEC_SHARE) { + smb_panic("register_initial_vuid: " + "Tried to register uid in security=share"); + } + + /* Limit allowed vuids to 16bits - VUID_OFFSET. */ + if (num_validated_vuids >= 0xFFFF-VUID_OFFSET) { + return UID_FIELD_INVALID; + } + + if((vuser = talloc_zero(NULL, user_struct)) == NULL) { + DEBUG(0,("register_initial_vuid: " + "Failed to talloc users struct!\n")); + return UID_FIELD_INVALID; + } + + /* Allocate a free vuid. Yes this is a linear search... */ + while( get_valid_user_struct_internal(next_vuid, + SERVER_ALLOCATED_REQUIRED_ANY) != NULL ) { + next_vuid++; + /* Check for vuid wrap. */ + if (next_vuid == UID_FIELD_INVALID) { + next_vuid = VUID_OFFSET; + } + } + + DEBUG(10,("register_initial_vuid: allocated vuid = %u\n", + (unsigned int)next_vuid )); + + vuser->vuid = next_vuid; + + /* + * This happens in an unfinished NTLMSSP session setup. We + * need to allocate a vuid between the first and second calls + * to NTLMSSP. + */ + next_vuid++; + num_validated_vuids++; + + DLIST_ADD(validated_users, vuser); + return vuser->vuid; +} + +static int register_homes_share(const char *username) +{ + int result; + struct passwd *pwd; + + result = lp_servicenumber(username); + if (result != -1) { + DEBUG(3, ("Using static (or previously created) service for " + "user '%s'; path = '%s'\n", username, + lp_pathname(result))); + return result; + } + + pwd = getpwnam_alloc(talloc_tos(), username); + + if ((pwd == NULL) || (pwd->pw_dir[0] == '\0')) { + DEBUG(3, ("No home directory defined for user '%s'\n", + username)); + TALLOC_FREE(pwd); + return -1; + } + + DEBUG(3, ("Adding homes service for user '%s' using home directory: " + "'%s'\n", username, pwd->pw_dir)); + + result = add_home_service(username, username, pwd->pw_dir); + + TALLOC_FREE(pwd); + return result; +} + +/** + * register that a valid login has been performed, establish 'session'. + * @param server_info The token returned from the authentication process. + * (now 'owned' by register_existing_vuid) + * + * @param session_key The User session key for the login session (now also + * 'owned' by register_existing_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_existing_vuid(uint16 vuid, + auth_serversupplied_info *server_info, + DATA_BLOB response_blob, + const char *smb_name) +{ + fstring tmp; + user_struct *vuser; + + vuser = get_partial_auth_user_struct(vuid); + if (!vuser) { + goto fail; + } + + /* Use this to keep tabs on all our info from the authentication */ + vuser->server_info = talloc_move(vuser, &server_info); + + /* This is a potentially untrusted username */ + alpha_strcpy(tmp, smb_name, ". _-$", sizeof(tmp)); + + vuser->server_info->sanitized_username = talloc_strdup( + vuser->server_info, tmp); + + DEBUG(10,("register_existing_vuid: (%u,%u) %s %s %s guest=%d\n", + (unsigned int)vuser->server_info->utok.uid, + (unsigned int)vuser->server_info->utok.gid, + vuser->server_info->unix_name, + vuser->server_info->sanitized_username, + pdb_get_domain(vuser->server_info->sam_account), + vuser->server_info->guest )); + + DEBUG(3, ("register_existing_vuid: User name: %s\t" + "Real name: %s\n", vuser->server_info->unix_name, + pdb_get_fullname(vuser->server_info->sam_account))); + + if (!vuser->server_info->ptok) { + DEBUG(1, ("register_existing_vuid: server_info does not " + "contain a user_token - cannot continue\n")); + goto fail; + } + + DEBUG(3,("register_existing_vuid: UNIX uid %d is UNIX user %s, " + "and will be vuid %u\n", (int)vuser->server_info->utok.uid, + vuser->server_info->unix_name, vuser->vuid)); + + next_vuid++; + num_validated_vuids++; + + if (!session_claim(vuser)) { + DEBUG(1, ("register_existing_vuid: Failed to claim session " + "for vuid=%d\n", + vuser->vuid)); + goto fail; + } + + /* Register a home dir service for this user if + (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->server_info->guest) { + vuser->homes_snum = register_homes_share( + vuser->server_info->unix_name); + } + + if (srv_is_signing_negotiated() && !vuser->server_info->guest && + !srv_signing_started()) { + /* Try and turn on server signing on the first non-guest + * sessionsetup. */ + srv_set_signing(vuser->server_info->user_session_key, response_blob); + } + + /* fill in the current_user_info struct */ + set_current_user_info( + vuser->server_info->sanitized_username, + vuser->server_info->unix_name, + pdb_get_fullname(vuser->server_info->sam_account), + pdb_get_domain(vuser->server_info->sam_account)); + + return vuser->vuid; + + fail: + + if (vuser) { + invalidate_vuid(vuid); + } + return UID_FIELD_INVALID; +} + +/**************************************************************************** + Add a name to the session users list. +****************************************************************************/ + +void add_session_user(const char *user) +{ + struct passwd *pw; + char *tmp; + + pw = Get_Pwnam_alloc(talloc_tos(), user); + + if (pw == NULL) { + return; + } + + if (session_userlist == NULL) { + session_userlist = SMB_STRDUP(pw->pw_name); + goto done; + } + + if (in_list(pw->pw_name,session_userlist,False) ) { + goto done; + } + + if (strlen(session_userlist) > 128 * 1024) { + DEBUG(3,("add_session_user: session userlist already " + "too large.\n")); + goto done; + } + + if (asprintf(&tmp, "%s %s", session_userlist, pw->pw_name) == -1) { + DEBUG(3, ("asprintf failed\n")); + goto done; + } + + SAFE_FREE(session_userlist); + session_userlist = tmp; + done: + TALLOC_FREE(pw); +} + +/**************************************************************************** + In security=share mode we need to store the client workgroup, as that's + what Vista uses for the NTLMv2 calculation. +****************************************************************************/ + +void add_session_workgroup(const char *workgroup) +{ + if (session_workgroup) { + SAFE_FREE(session_workgroup); + } + session_workgroup = smb_xstrdup(workgroup); +} + +/**************************************************************************** + In security=share mode we need to return the client workgroup, as that's + what Vista uses for the NTLMv2 calculation. +****************************************************************************/ + +const char *get_session_workgroup(void) +{ + return session_workgroup; +} + +/**************************************************************************** + 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, " + "let's try without specifying it\n")); + } + + DEBUG(5,("looking for user %s of domain %s in netgroup %s\n", + user, mydomain?mydomain:"(ANY)", 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?mydomain:"(ANY)", 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(talloc_tos(), &invalid, lp_invalid_users(snum)); + if (invalid && + str_list_substitute(invalid, "%S", lp_servicename(snum))) { + + /* This is used in sec=share only, so no current user + * around to pass to str_list_sub_basic() */ + + if ( invalid && str_list_sub_basic(invalid, "", "") ) { + ret = !user_in_list(user, + (const char **)invalid); + } + } + } + TALLOC_FREE(invalid); + + if (ret && lp_valid_users(snum)) { + str_list_copy(talloc_tos(), &valid, lp_valid_users(snum)); + if ( valid && + str_list_substitute(valid, "%S", lp_servicename(snum)) ) { + + /* This is used in sec=share only, so no current user + * around to pass to str_list_sub_basic() */ + + if ( valid && str_list_sub_basic(valid, "", "") ) { + ret = user_in_list(user, (const char **)valid); + } + } + } + TALLOC_FREE(valid); + + if (ret && lp_onlyuser(snum)) { + char **user_list = str_list_make( + talloc_tos(), 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); + } + TALLOC_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 onto the heap before + * use. Bug pointed out by leon@eatworms.swmed.edu. + */ + + if (gptr) { + char *member_list = NULL; + size_t list_len = 0; + char *member; + int i; + + for(i = 0; gptr->gr_mem && gptr->gr_mem[i]; i++) { + list_len += strlen(gptr->gr_mem[i])+1; + } + list_len++; + + member_list = (char *)SMB_MALLOC(list_len); + if (!member_list) { + endgrent(); + return NULL; + } + + *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; + + DEBUG(10,("validate_group: = gr_mem = " + "%s\n", gptr->gr_mem[i])); + + safe_strcpy(member, gptr->gr_mem[i], + list_len - (member-member_list)); + member += member_len; + } + + endgrent(); + + member = member_list; + while (*member) { + if (user_ok(member,snum) && + password_ok(member,password)) { + char *name = talloc_strdup(talloc_tos(), + member); + SAFE_FREE(member_list); + return name; + } + + DEBUG(10,("validate_group = member = %s\n", + member)); + + member += strlen(member) + 1; + } + + SAFE_FREE(member_list); + } 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; + char *saveptr; + + if ( session_userlist ) + user_list = SMB_STRDUP(session_userlist); + else + user_list = SMB_STRDUP(""); + + if (!user_list) + return(False); + + for (auser = strtok_r(user_list, LIST_SEP, &saveptr); + !ok && auser; + auser = strtok_r(NULL, LIST_SEP, &saveptr)) { + 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)) { + TALLOC_CTX *ctx = talloc_tos(); + char *auser; + char *user_list = talloc_strdup(ctx, lp_username(snum)); + char *saveptr; + + if (!user_list) { + goto check_guest; + } + + user_list = talloc_string_sub(ctx, + user_list, + "%S", + lp_servicename(snum)); + + if (!user_list) { + goto check_guest; + } + + for (auser = strtok_r(user_list, LIST_SEP, &saveptr); + auser && !ok; + auser = strtok_r(NULL, LIST_SEP, &saveptr)) { + 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_guest: + + /* check for a normal guest connection */ + if (!ok && GUEST_OK(snum)) { + struct passwd *guest_pw; + fstring guestname; + fstrcpy(guestname,lp_guestaccount()); + guest_pw = Get_Pwnam_alloc(talloc_tos(), guestname); + if (guest_pw != NULL) { + 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)); + } + TALLOC_FREE(guest_pw); + *guest = True; + } + + if (ok && !user_ok(user, snum)) { + DEBUG(0,("authorise_login: rejected invalid user %s\n",user)); + ok = False; + } + + return(ok); +} |