/* Unix SMB/Netbios implementation. Version 1.9. SMB NT Security Descriptor / Unix permission conversion. Copyright (C) Jeremy Allison 1994-2000 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" /**************************************************************************** Data structures representing the internal ACE format. ****************************************************************************/ enum ace_owner {UID_ACE, GID_ACE, WORLD_ACE}; enum ace_attribute {ALLOW_ACE, DENY_ACE}; /* Used for incoming NT ACLS. */ typedef union posix_id { uid_t uid; gid_t gid; int world; } posix_id; typedef struct canon_ace { struct canon_ace *next, *prev; SMB_ACL_TAG_T type; mode_t perms; /* Only use S_I(R|W|X)USR mode bits here. */ DOM_SID sid; enum ace_owner owner_type; enum ace_attribute attr; posix_id unix_ug; } canon_ace; #define ALL_ACE_PERMS (S_IRUSR|S_IWUSR|S_IXUSR) /**************************************************************************** Functions to manipulate the internal ACE format. ****************************************************************************/ /**************************************************************************** Count a linked list of canonical ACE entries. ****************************************************************************/ static size_t count_canon_ace_list( canon_ace *list_head ) { size_t count = 0; canon_ace *ace; for (ace = list_head; ace; ace = ace->next) count++; return count; } /**************************************************************************** Free a linked list of canonical ACE entries. ****************************************************************************/ static void free_canon_ace_list( canon_ace *list_head ) { while (list_head) { canon_ace *old_head = list_head; DLIST_REMOVE(list_head, list_head); free(old_head); } } /**************************************************************************** Function to duplicate a canon_ace entry. ****************************************************************************/ static canon_ace *dup_canon_ace( canon_ace *src_ace) { canon_ace *dst_ace = (canon_ace *)malloc(sizeof(canon_ace)); if (dst_ace == NULL) return NULL; *dst_ace = *src_ace; dst_ace->prev = dst_ace->next = NULL; return dst_ace; } /**************************************************************************** Function to create owner and group SIDs from a SMB_STRUCT_STAT. ****************************************************************************/ static void create_file_sids(SMB_STRUCT_STAT *psbuf, DOM_SID *powner_sid, DOM_SID *pgroup_sid) { uid_to_sid( powner_sid, psbuf->st_uid ); gid_to_sid( pgroup_sid, psbuf->st_gid ); } /**************************************************************************** Print out a canon ace. ****************************************************************************/ static void print_canon_ace(canon_ace *pace, int num) { fstring str; dbgtext( "canon_ace index %d. Type = %s ", num, pace->attr == ALLOW_ACE ? "allow" : "deny" ); dbgtext( "SID = %s ", sid_to_string( str, &pace->sid)); if (pace->owner_type == UID_ACE) { struct passwd *pass = sys_getpwuid(pace->unix_ug.uid); dbgtext( "uid %u (%s) ", (unsigned int)pace->unix_ug.uid, pass ? pass->pw_name : "UNKNOWN"); } else if (pace->owner_type == GID_ACE) { struct group *grp = getgrgid(pace->unix_ug.gid); dbgtext( "gid %u (%s) ", (unsigned int)pace->unix_ug.gid, grp ? grp->gr_name : "UNKNOWN"); } else dbgtext( "other "); switch (pace->type) { case SMB_ACL_USER: dbgtext( "SMB_ACL_USER "); break; case SMB_ACL_USER_OBJ: dbgtext( "SMB_ACL_USER_OBJ "); break; case SMB_ACL_GROUP: dbgtext( "SMB_ACL_GROUP "); break; case SMB_ACL_GROUP_OBJ: dbgtext( "SMB_ACL_GROUP_OBJ "); break; case SMB_ACL_OTHER: dbgtext( "SMB_ACL_OTHER "); break; } dbgtext( "perms "); dbgtext( "%c", pace->perms & S_IRUSR ? 'r' : '-'); dbgtext( "%c", pace->perms & S_IWUSR ? 'w' : '-'); dbgtext( "%c\n", pace->perms & S_IXUSR ? 'x' : '-'); } /**************************************************************************** Print out a canon ace list. ****************************************************************************/ static void print_canon_ace_list(const char *name, canon_ace *ace_list) { int count = 0; if( DEBUGLVL( 10 )) { dbgtext( "print_canon_ace_list: %s\n", name ); for (;ace_list; ace_list = ace_list->next, count++) print_canon_ace(ace_list, count ); } } /**************************************************************************** Merge aces with a common sid - if both are allow or deny, OR the permissions together and delete the second one. If the first is deny, mask the permissions off and delete the allow if the permissions become zero, delete the deny if the permissions are non zero. ****************************************************************************/ static void merge_aces( canon_ace **pp_list_head ) { canon_ace *list_head = *pp_list_head; canon_ace *curr_ace_outer; canon_ace *curr_ace_outer_next; /* * First, merge allow entries with identical SIDs, and deny entries * with identical SIDs. */ for (curr_ace_outer = list_head; curr_ace_outer; curr_ace_outer = curr_ace_outer_next) { canon_ace *curr_ace; canon_ace *curr_ace_next; curr_ace_outer_next = curr_ace_outer->next; /* Save the link in case we delete. */ for (curr_ace = curr_ace_outer->next; curr_ace; curr_ace = curr_ace_next) { curr_ace_next = curr_ace->next; /* Save the link in case of delete. */ if (sid_equal(&curr_ace->sid, &curr_ace_outer->sid) && (curr_ace->attr == curr_ace_outer->attr)) { if( DEBUGLVL( 10 )) { dbgtext("merge_aces: Merging ACE's\n"); print_canon_ace( curr_ace_outer, 0); print_canon_ace( curr_ace, 0); } /* Merge two allow or two deny ACE's. */ curr_ace_outer->perms |= curr_ace->perms; DLIST_REMOVE(list_head, curr_ace); free(curr_ace); curr_ace_outer_next = curr_ace_outer->next; /* We may have deleted the link. */ } } } /* * Now go through and mask off allow permissions with deny permissions. * We can delete either the allow or deny here as we know that each SID * appears only once in the list. */ for (curr_ace_outer = list_head; curr_ace_outer; curr_ace_outer = curr_ace_outer_next) { canon_ace *curr_ace; canon_ace *curr_ace_next; curr_ace_outer_next = curr_ace_outer->next; /* Save the link in case we delete. */ for (curr_ace = curr_ace_outer->next; curr_ace; curr_ace = curr_ace_next) { curr_ace_next = curr_ace->next; /* Save the link in case of delete. */ /* * Subtract ACE's with different entries. Due to the ordering constraints * we've put on the ACL, we know the deny must be the first one. */ if (sid_equal(&curr_ace->sid, &curr_ace_outer->sid) && (curr_ace_outer->attr == DENY_ACE) && (curr_ace->attr == ALLOW_ACE)) { if( DEBUGLVL( 10 )) { dbgtext("merge_aces: Masking ACE's\n"); print_canon_ace( curr_ace_outer, 0); print_canon_ace( curr_ace, 0); } curr_ace->perms &= ~curr_ace_outer->perms; if (curr_ace->perms == 0) { /* * The deny overrides the allow. Remove the allow. */ DLIST_REMOVE(list_head, curr_ace); free(curr_ace); curr_ace_outer_next = curr_ace_outer->next; /* We may have deleted the link. */ } else { /* * Even after removing permissions, there * are still allow permissions - delete the deny. * It is safe to delete the deny here, * as we are guarenteed by the deny first * ordering that all the deny entries for * this SID have already been merged into one * before we can get to an allow ace. */ DLIST_REMOVE(list_head, curr_ace_outer); free(curr_ace_outer); } } } /* end for curr_ace */ } /* end for curr_ace_outer */ /* We may have modified the list. */ *pp_list_head = list_head; } /**************************************************************************** Map canon_ace perms to permission bits NT. The attr element is not used here - we only process deny entries on set, not get. Deny entries are implicit on get with ace->perms = 0. ****************************************************************************/ static SEC_ACCESS map_canon_ace_perms(int *pacl_type, DOM_SID *powner_sid, canon_ace *ace) { SEC_ACCESS sa; uint32 nt_mask = 0; *pacl_type = SEC_ACE_TYPE_ACCESS_ALLOWED; if ((ace->perms & ALL_ACE_PERMS) == ALL_ACE_PERMS) { nt_mask = UNIX_ACCESS_RWX; } else if ((ace->perms & ALL_ACE_PERMS) == (mode_t)0) { /* * Here we differentiate between the owner and any other user. */ if (sid_equal(powner_sid, &ace->sid)) { nt_mask = UNIX_ACCESS_NONE; } else { /* Not owner, no access. */ if (ace->type == SMB_ACL_USER) { /* user objects can be deny entries. */ *pacl_type = SEC_ACE_TYPE_ACCESS_DENIED; nt_mask = GENERIC_ALL_ACCESS; } else nt_mask = UNIX_ACCESS_NONE; } } else { nt_mask |= ((ace->perms & S_IRUSR) ? UNIX_ACCESS_R : 0 ); nt_mask |= ((ace->perms & S_IWUSR) ? UNIX_ACCESS_W : 0 ); nt_mask |= ((ace->perms & S_IXUSR) ? UNIX_ACCESS_X : 0 ); } DEBUG(10,("map_canon_ace_perms: Mapped (UNIX) %x to (NT) %x\n", (unsigned int)ace->perms, (unsigned int)nt_mask )); init_sec_access(&sa,nt_mask); return sa; } /**************************************************************************** Map NT perms to a UNIX mode_t. ****************************************************************************/ #define FILE_SPECIFIC_READ_BITS (FILE_READ_DATA|FILE_READ_EA|FILE_READ_ATTRIBUTES) #define FILE_SPECIFIC_WRITE_BITS (FILE_WRITE_DATA|FILE_APPEND_DATA|FILE_WRITE_EA|FILE_WRITE_ATTRIBUTES) #define FILE_SPECIFIC_EXECUTE_BITS (FILE_EXECUTE) static mode_t map_nt_perms( SEC_ACCESS sec_access, int type) { mode_t mode = 0; switch(type) { case S_IRUSR: if(sec_access.mask & GENERIC_ALL_ACCESS) mode = S_IRUSR|S_IWUSR|S_IXUSR; else { mode |= (sec_access.mask & (GENERIC_READ_ACCESS|FILE_SPECIFIC_READ_BITS)) ? S_IRUSR : 0; mode |= (sec_access.mask & (GENERIC_WRITE_ACCESS|FILE_SPECIFIC_WRITE_BITS)) ? S_IWUSR : 0; mode |= (sec_access.mask & (GENERIC_EXECUTE_ACCESS|FILE_SPECIFIC_EXECUTE_BITS)) ? S_IXUSR : 0; } break; case S_IRGRP: if(sec_access.mask & GENERIC_ALL_ACCESS) mode = S_IRGRP|S_IWGRP|S_IXGRP; else { mode |= (sec_access.mask & (GENERIC_READ_ACCESS|FILE_SPECIFIC_READ_BITS)) ? S_IRGRP : 0; mode |= (sec_access.mask & (GENERIC_WRITE_ACCESS|FILE_SPECIFIC_WRITE_BITS)) ? S_IWGRP : 0; mode |= (sec_access.mask & (GENERIC_EXECUTE_ACCESS|FILE_SPECIFIC_EXECUTE_BITS)) ? S_IXGRP : 0; } break; case S_IROTH: if(sec_access.mask & GENERIC_ALL_ACCESS) mode = S_IROTH|S_IWOTH|S_IXOTH; else { mode |= (sec_access.mask & (GENERIC_READ_ACCESS|FILE_SPECIFIC_READ_BITS)) ? S_IROTH : 0; mode |= (sec_access.mask & (GENERIC_WRITE_ACCESS|FILE_SPECIFIC_WRITE_BITS)) ? S_IWOTH : 0; mode |= (sec_access.mask & (GENERIC_EXECUTE_ACCESS|FILE_SPECIFIC_EXECUTE_BITS)) ? S_IXOTH : 0; } break; } return mode; } /**************************************************************************** Unpack a SEC_DESC into a UNIX owner and group. ****************************************************************************/ static BOOL unpack_nt_owners(SMB_STRUCT_STAT *psbuf, uid_t *puser, gid_t *pgrp, uint32 security_info_sent, SEC_DESC *psd) { DOM_SID owner_sid; DOM_SID grp_sid; enum SID_NAME_USE sid_type; *puser = (uid_t)-1; *pgrp = (gid_t)-1; if(security_info_sent == 0) { DEBUG(0,("unpack_nt_owners: no security info sent !\n")); return False; } /* * Validate the owner and group SID's. */ memset(&owner_sid, '\0', sizeof(owner_sid)); memset(&grp_sid, '\0', sizeof(grp_sid)); DEBUG(5,("unpack_nt_owners: validating owner_sids.\n")); /* * Don't immediately fail if the owner sid cannot be validated. * This may be a group chown only set. */ if (security_info_sent & OWNER_SECURITY_INFORMATION) { sid_copy(&owner_sid, psd->owner_sid); if (!sid_to_uid( &owner_sid, puser, &sid_type)) DEBUG(3,("unpack_nt_owners: unable to validate owner sid.\n")); } /* * Don't immediately fail if the group sid cannot be validated. * This may be an owner chown only set. */ if (security_info_sent & GROUP_SECURITY_INFORMATION) { sid_copy(&grp_sid, psd->grp_sid); if (!sid_to_gid( &grp_sid, pgrp, &sid_type)) DEBUG(3,("unpack_nt_owners: unable to validate group sid.\n")); } DEBUG(5,("unpack_nt_owners: owner_sids validated.\n")); return True; } /**************************************************************************** Create a default mode for a directory default ACE. ****************************************************************************/ static mode_t get_default_ace_mode(files_struct *fsp, int type) { mode_t force_mode = lp_force_dir_security_mode(SNUM(fsp->conn)); mode_t mode = 0; DEBUG(10,("get_default_ace_mode: force_mode = 0%o\n", (int)force_mode )); switch(type) { case S_IRUSR: mode |= (force_mode & S_IRUSR) ? S_IRUSR : 0; mode |= (force_mode & S_IWUSR) ? S_IWUSR : 0; mode |= (force_mode & S_IXUSR) ? S_IXUSR : 0; break; case S_IRGRP: mode |= (force_mode & S_IRGRP) ? S_IRUSR : 0; mode |= (force_mode & S_IWGRP) ? S_IWUSR : 0; mode |= (force_mode & S_IXGRP) ? S_IXUSR : 0; break; case S_IROTH: mode |= (force_mode & S_IROTH) ? S_IRUSR : 0; mode |= (force_mode & S_IWOTH) ? S_IWUSR : 0; mode |= (force_mode & S_IXOTH) ? S_IXUSR : 0; break; } DEBUG(10,("get_default_ace_mode: returning mode = 0%o\n", (int)mode )); return mode; } /**************************************************************************** A well formed POSIX file or default ACL has at least 3 entries, a SMB_ACL_USER_OBJ, SMB_ACL_GROUP_OBJ, SMB_ACL_OTHER_OBJ. In addition, the owner must always have at least read access. ****************************************************************************/ static BOOL ensure_canon_entry_valid(canon_ace **pp_ace, files_struct *fsp, DOM_SID *pfile_owner_sid, DOM_SID *pfile_grp_sid, SMB_STRUCT_STAT *pst, BOOL default_acl) { extern DOM_SID global_sid_World; canon_ace *pace; BOOL got_user = False; BOOL got_grp = False; BOOL got_other = False; for (pace = *pp_ace; pace; pace = pace->next) { if (pace->type == SMB_ACL_USER_OBJ) { /* Ensure owner has read access. */ if (pace->perms == (mode_t)0) pace->perms = S_IRUSR; got_user = True; } else if (pace->type == SMB_ACL_GROUP_OBJ) got_grp = True; else if (pace->type == SMB_ACL_OTHER) got_other = True; } if (!got_user) { if ((pace = (canon_ace *)malloc(sizeof(canon_ace))) == NULL) { DEBUG(0,("ensure_canon_entry_valid: malloc fail.\n")); return False; } ZERO_STRUCTP(pace); pace->type = SMB_ACL_USER_OBJ; pace->owner_type = UID_ACE; pace->unix_ug.uid = pst->st_uid; pace->sid = *pfile_owner_sid; /* Ensure owner has read access. */ pace->perms = default_acl ? get_default_ace_mode(fsp, S_IRUSR) : S_IRUSR; if (pace->perms == (mode_t)0) pace->perms = S_IRUSR; pace->attr = ALLOW_ACE; DLIST_ADD(*pp_ace, pace); } if (!got_grp) { if ((pace = (canon_ace *)malloc(sizeof(canon_ace))) == NULL) { DEBUG(0,("ensure_canon_entry_valid: malloc fail.\n")); return False; } ZERO_STRUCTP(pace); pace->type = SMB_ACL_GROUP_OBJ; pace->owner_type = GID_ACE; pace->unix_ug.uid = pst->st_gid; pace->sid = *pfile_grp_sid; pace->perms = default_acl ? get_default_ace_mode(fsp, S_IRGRP): 0; pace->attr = ALLOW_ACE; DLIST_ADD(*pp_ace, pace); } if (!got_other) { if ((pace = (canon_ace *)malloc(sizeof(canon_ace))) == NULL) { DEBUG(0,("ensure_canon_entry_valid: malloc fail.\n")); return False; } ZERO_STRUCTP(pace); pace->type = SMB_ACL_OTHER; pace->owner_type = WORLD_ACE; pace->unix_ug.world = -1; pace->sid = global_sid_World; pace->perms = default_acl ? get_default_ace_mode(fsp, S_IROTH): 0; pace->attr = ALLOW_ACE; DLIST_ADD(*pp_ace, pace); } return True; } /**************************************************************************** Unpack a SEC_DESC into two canonical ace lists. ****************************************************************************/ static BOOL create_canon_ace_lists(files_struct *fsp, DOM_SID *pfile_owner_sid, DOM_SID *pfile_grp_sid, canon_ace **ppfile_ace, canon_ace **ppdir_ace, SEC_ACL *dacl) { extern DOM_SID global_sid_World; BOOL all_aces_are_inherit_only = (fsp->is_directory ? True : False); canon_ace *file_ace = NULL; canon_ace *dir_ace = NULL; canon_ace *tmp_ace = NULL; canon_ace *current_ace = NULL; BOOL got_dir_allow = False; BOOL got_file_allow = False; int i; *ppfile_ace = NULL; *ppdir_ace = NULL; for(i = 0; i < dacl->num_aces; i++) { enum SID_NAME_USE sid_type; SEC_ACE *psa = &dacl->ace[i]; if((psa->type != SEC_ACE_TYPE_ACCESS_ALLOWED) && (psa->type != SEC_ACE_TYPE_ACCESS_DENIED)) { free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); DEBUG(3,("create_canon_ace_lists: unable to set anything but an ALLOW or DENY ACE.\n")); return False; } /* * The security mask may be UNIX_ACCESS_NONE which should map into * no permissions (we overload the WRITE_OWNER bit for this) or it * should be one of the ALL/EXECUTE/READ/WRITE bits. Arrange for this * to be so. Any other bits override the UNIX_ACCESS_NONE bit. */ psa->info.mask &= (GENERIC_ALL_ACCESS|GENERIC_EXECUTE_ACCESS|GENERIC_WRITE_ACCESS| GENERIC_READ_ACCESS|UNIX_ACCESS_NONE|FILE_ALL_ATTRIBUTES); if(psa->info.mask != UNIX_ACCESS_NONE) psa->info.mask &= ~UNIX_ACCESS_NONE; /* * Create a cannon_ace entry representing this NT DACL ACE. */ if ((current_ace = (canon_ace *)malloc(sizeof(canon_ace))) == NULL) { free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); DEBUG(0,("create_canon_ace_lists: malloc fail.\n")); return False; } ZERO_STRUCTP(current_ace); sid_copy(¤t_ace->sid, &psa->sid); /* * Try and work out if the SID is a user or group * as we need to flag these differently for POSIX. */ if( sid_equal(¤t_ace->sid, &global_sid_World)) { current_ace->owner_type = WORLD_ACE; current_ace->unix_ug.world = -1; } else if (sid_to_uid( ¤t_ace->sid, ¤t_ace->unix_ug.uid, &sid_type)) { current_ace->owner_type = UID_ACE; } else if (sid_to_gid( ¤t_ace->sid, ¤t_ace->unix_ug.gid, &sid_type)) { current_ace->owner_type = GID_ACE; } else { fstring str; free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); free(current_ace); DEBUG(0,("create_canon_ace_lists: unable to map SID %s to uid or gid.\n", sid_to_string(str, ¤t_ace->sid) )); return False; } /* * Map the given NT permissions into a UNIX mode_t containing only * S_I(R|W|X)USR bits. */ current_ace->perms |= map_nt_perms( psa->info, S_IRUSR); current_ace->attr = (psa->type == SEC_ACE_TYPE_ACCESS_ALLOWED) ? ALLOW_ACE : DENY_ACE; /* * Now note what kind of a POSIX ACL this should map to. */ if(sid_equal(¤t_ace->sid, pfile_owner_sid)) { /* Note we should apply the default mode/mask here.... FIXME ! JRA */ current_ace->type = SMB_ACL_USER_OBJ; } else if( sid_equal(¤t_ace->sid, pfile_grp_sid)) { /* Note we should apply the default mode/mask here.... FIXME ! JRA */ current_ace->type = SMB_ACL_GROUP_OBJ; } else if( sid_equal(¤t_ace->sid, &global_sid_World)) { /* Note we should apply the default mode/mask here.... FIXME ! JRA */ current_ace->type = SMB_ACL_OTHER; } else { /* * Could be a SMB_ACL_USER or SMB_ACL_GROUP. Check by * looking at owner_type. */ current_ace->type = (current_ace->owner_type == UID_ACE) ? SMB_ACL_USER : SMB_ACL_GROUP; } /* * Now add the created ace to either the file list, the directory * list, or both. We *MUST* preserve the order here (hence we use * DLIST_ADD_END) as NT ACLs are order dependent. */ if (fsp->is_directory) { /* * We can only add to the default POSIX ACE list if the ACE is * designed to be inherited by both files and directories. */ if ((psa->flags & (SEC_ACE_FLAG_OBJECT_INHERIT|SEC_ACE_FLAG_CONTAINER_INHERIT)) == (SEC_ACE_FLAG_OBJECT_INHERIT|SEC_ACE_FLAG_CONTAINER_INHERIT)) { DLIST_ADD_END(dir_ace, current_ace, tmp_ace); /* * Note if this was an allow ace. We can't process * any further deny ace's after this. */ if (current_ace->attr == ALLOW_ACE) got_dir_allow = True; if ((current_ace->attr == DENY_ACE) && got_dir_allow) { DEBUG(0,("create_canon_ace_lists: malformed ACL in inheritable ACL ! \ Deny entry after Allow entry. Failing to set on file %s.\n", fsp->fsp_name )); free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); free(current_ace); return False; } if( DEBUGLVL( 10 )) { dbgtext("create_canon_ace_lists: adding dir ACL:\n"); print_canon_ace( current_ace, 0); } /* * If this is not an inherit only ACE we need to add a duplicate * to the file acl. */ if (!(psa->flags & SEC_ACE_FLAG_INHERIT_ONLY)) { canon_ace *dup_ace = dup_canon_ace(current_ace); if (!dup_ace) { DEBUG(0,("create_canon_ace_lists: malloc fail !\n")); free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); return False; } current_ace = dup_ace; } else { current_ace = NULL; } } } /* * Only add to the file ACL if not inherit only. */ if (!(psa->flags & SEC_ACE_FLAG_INHERIT_ONLY)) { DLIST_ADD_END(file_ace, current_ace, tmp_ace); /* * Note if this was an allow ace. We can't process * any further deny ace's after this. */ if (current_ace->attr == ALLOW_ACE) got_file_allow = True; if ((current_ace->attr == DENY_ACE) && got_file_allow) { DEBUG(0,("create_canon_ace_lists: malformed ACL in file ACL ! \ Deny entry after Allow entry. Failing to set on file %s.\n", fsp->fsp_name )); free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); free(current_ace); return False; } if( DEBUGLVL( 10 )) { dbgtext("create_canon_ace_lists: adding file ACL:\n"); print_canon_ace( current_ace, 0); } all_aces_are_inherit_only = False; current_ace = NULL; } /* * Free if ACE was not added. */ if (current_ace) free(current_ace); } if (fsp->is_directory && all_aces_are_inherit_only) { /* * Windows 2000 is doing one of these weird 'inherit acl' * traverses to conserve NTFS ACL resources. Just pretend * there was no DACL sent. JRA. */ DEBUG(10,("create_canon_ace_lists: Win2k inherit acl traverse. Ignoring DACL.\n")); free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); file_ace = NULL; dir_ace = NULL; } *ppfile_ace = file_ace; *ppdir_ace = dir_ace; return True; } /**************************************************************************** Check if a given uid/SID is in a group gid/SID. This is probably very expensive and will need optimisation. A *lot* of optimisation :-). JRA. ****************************************************************************/ static BOOL uid_entry_in_group( canon_ace *uid_ace, canon_ace *group_ace ) { extern DOM_SID global_sid_World; struct passwd *pass = NULL; struct group *gptr = NULL; /* "Everyone" always matches every uid. */ if (sid_equal(&group_ace->sid, &global_sid_World)) return True; if (!(pass = sys_getpwuid(uid_ace->unix_ug.uid))) return False; if (!(gptr = getgrgid(group_ace->unix_ug.gid))) return False; /* * Due to the winbind interfaces we need to do this via names, * not uids/gids. */ return user_in_group_list(pass->pw_name, gptr->gr_name ); } /**************************************************************************** ASCII art time again... JRA :-). We have 3 cases to process when moving from an NT ACL to a POSIX ACL. Firstly, we insist the ACL is in canonical form (ie. all DENY entries preceede ALLOW entries). Secondly, the merge code has ensured that all duplicate SID entries for allow or deny have been merged, so the same SID can only appear once in the deny list or once in the allow list. We then process as follows : --------------------------------------------------------------------------- First pass - look for a Everyone DENY entry. If it is deny all (rwx) trunate the list at this point. Else, walk the list from this point and use the deny permissions of this entry as a mask on all following allow entries. Finally, delete the Everyone DENY entry (we have applied it to everything possible). In addition, in this pass we remove any DENY entries that have no permissions (ie. they are a DENY nothing). --------------------------------------------------------------------------- Second pass - only deal with deny user entries. DENY user1 (perms XXX) new_perms = 0 for all following allow group entries where user1 is in group new_perms |= group_perms; user1 entry perms = new_perms & ~ XXX; Convert the deny entry to an allow entry with the new perms and push to the end of the list. Note if the user was in no groups this maps to a specific allow nothing entry for this user. The common case from the NT ACL choser (userX deny all) is optimised so we don't do the group lookup - we just map to an allow nothing entry. What we're doing here is inferring the allow permissions the person setting the ACE on user1 wanted by looking at the allow permissions on the groups the user is currently in. This will be a snapshot, depending on group membership but is the best we can do and has the advantage of failing closed rather than open. --------------------------------------------------------------------------- Third pass - only deal with deny group entries. DENY group1 (perms XXX) for all following allow user entries where user is in group1 user entry perms = user entry perms & ~ XXX; If there is a group Everyone allow entry with permissions YYY, convert the group1 entry to an allow entry and modify its permissions to be : new_perms = YYY & ~ XXX and push to the end of the list. If there is no group Everyone allow entry then convert the group1 entry to a allow nothing entry and push to the end of the list. Note that the common case from the NT ACL choser (groupX deny all) cannot be optimised here as we need to modify user entries who are in the group to change them to a deny all also. What we're doing here is modifying the allow permissions of user entries (which are more specific in POSIX ACLs) to mask out the explicit deny set on the group they are in. This will be a snapshot depending on current group membership but is the best we can do and has the advantage of failing closed rather than open. --------------------------------------------------------------------------- Note we *MUST* do the deny user pass first as this will convert deny user entries into allow user entries which can then be processed by the deny group pass. The above algorithm took a *lot* of thinking about - hence this explaination :-). JRA. ****************************************************************************/ /**************************************************************************** Process a canon_ace list entries. This is very complex code. We need to go through and remove the "deny" permissions from any allow entry that matches the id of this entry. We have already refused any NT ACL that wasn't in correct order (DENY followed by ALLOW). If any allow entry ends up with zero permissions, we just remove it (to fail safe). We have already removed any duplicate ace entries. Treat an "Everyone" DENY_ACE as a special case - use it to mask all allow entries. ****************************************************************************/ static void process_deny_list( canon_ace **pp_ace_list ) { extern DOM_SID global_sid_World; canon_ace *ace_list = *pp_ace_list; canon_ace *curr_ace = NULL; canon_ace *curr_ace_next = NULL; /* Pass 1 above - look for an Everyone, deny entry. */ for (curr_ace = ace_list; curr_ace; curr_ace = curr_ace_next) { canon_ace *allow_ace_p; curr_ace_next = curr_ace->next; /* So we can't lose the link. */ if (curr_ace->attr != DENY_ACE) continue; if (curr_ace->perms == (mode_t)0) { /* Deny nothing entry - delete. */ DLIST_REMOVE(ace_list, curr_ace); continue; } if (!sid_equal(&curr_ace->sid, &global_sid_World)) continue; /* JRATEST - assert. */ SMB_ASSERT(curr_ace->owner_type == WORLD_ACE); if (curr_ace->perms == ALL_ACE_PERMS) { /* * Optimisation. This is a DENY_ALL to Everyone. Truncate the * list at this point including this entry. */ canon_ace *prev_entry = curr_ace->prev; free_canon_ace_list( curr_ace ); if (prev_entry) prev_entry->next = NULL; else { /* We deleted the entire list. */ ace_list = NULL; } break; } for (allow_ace_p = curr_ace->next; allow_ace_p; allow_ace_p = allow_ace_p->next) { /* * Only mask off allow entries. */ if (allow_ace_p->attr != ALLOW_ACE) continue; allow_ace_p->perms &= ~curr_ace->perms; } /* * Now it's been applied, remove it. */ DLIST_REMOVE(ace_list, curr_ace); } /* Pass 2 above - deal with deny user entries. */ for (curr_ace = ace_list; curr_ace; curr_ace = curr_ace_next) { mode_t new_perms = (mode_t)0; canon_ace *allow_ace_p; canon_ace *tmp_ace; curr_ace_next = curr_ace->next; /* So we can't lose the link. */ if (curr_ace->attr != DENY_ACE) continue; if (curr_ace->owner_type != UID_ACE) continue; if (curr_ace->perms == ALL_ACE_PERMS) { /* * Optimisation - this is a deny everything to this user. * Convert to an allow nothing and push to the end of the list. */ curr_ace->attr = ALLOW_ACE; curr_ace->perms = (mode_t)0; DLIST_DEMOTE(ace_list, curr_ace, tmp_ace); continue; } for (allow_ace_p = curr_ace->next; allow_ace_p; allow_ace_p = allow_ace_p->next) { if (allow_ace_p->attr != ALLOW_ACE) continue; /* We process GID_ACE and WORLD_ACE entries only. */ if (allow_ace_p->owner_type == UID_ACE) continue; if (uid_entry_in_group( curr_ace, allow_ace_p)) new_perms |= allow_ace_p->perms; } /* * Convert to a allow entry, modify the perms and push to the end * of the list. */ curr_ace->attr = ALLOW_ACE; curr_ace->perms = (new_perms & ~curr_ace->perms); DLIST_DEMOTE(ace_list, curr_ace, tmp_ace); } /* Pass 3 above - deal with deny group entries. */ for (curr_ace = ace_list; curr_ace; curr_ace = curr_ace_next) { canon_ace *tmp_ace; canon_ace *allow_ace_p; canon_ace *allow_everyone_p = NULL; curr_ace_next = curr_ace->next; /* So we can't lose the link. */ if (curr_ace->attr != DENY_ACE) continue; if (curr_ace->owner_type != GID_ACE) continue; for (allow_ace_p = curr_ace->next; allow_ace_p; allow_ace_p = allow_ace_p->next) { if (allow_ace_p->attr != ALLOW_ACE) continue; /* Store a pointer to the Everyone allow, if it exists. */ if (allow_ace_p->owner_type == WORLD_ACE) allow_everyone_p = allow_ace_p; /* We process UID_ACE entries only. */ if (allow_ace_p->owner_type != UID_ACE) continue; /* Mask off the deny group perms. */ if (uid_entry_in_group( allow_ace_p, curr_ace)) allow_ace_p->perms &= ~curr_ace->perms; } /* * Convert the deny to an allow with the correct perms and * push to the end of the list. */ curr_ace->attr = ALLOW_ACE; if (allow_everyone_p) curr_ace->perms = allow_everyone_p->perms & ~curr_ace->perms; else curr_ace->perms = (mode_t)0; DLIST_DEMOTE(ace_list, curr_ace, tmp_ace); } *pp_ace_list = ace_list; } /**************************************************************************** Unpack a SEC_DESC into two canonical ace lists. We don't depend on this succeeding. ****************************************************************************/ static BOOL unpack_canon_ace(files_struct *fsp, SMB_STRUCT_STAT *pst, DOM_SID *pfile_owner_sid, DOM_SID *pfile_grp_sid, canon_ace **ppfile_ace, canon_ace **ppdir_ace, uint32 security_info_sent, SEC_DESC *psd) { canon_ace *file_ace = NULL; canon_ace *dir_ace = NULL; *ppfile_ace = NULL; *ppdir_ace = NULL; if(security_info_sent == 0) { DEBUG(0,("unpack_canon_ace: no security info sent !\n")); return False; } /* * If no DACL then this is a chown only security descriptor. */ if(!(security_info_sent & DACL_SECURITY_INFORMATION) || !psd->dacl) return True; /* * Now go through the DACL and create the canon_ace lists. */ if (!create_canon_ace_lists( fsp, pfile_owner_sid, pfile_grp_sid, &file_ace, &dir_ace, psd->dacl)) return False; if ((file_ace == NULL) && (dir_ace == NULL)) { /* W2K traverse DACL set - ignore. */ return True; } /* * Go through the canon_ace list and merge entries * belonging to identical users of identical allow or deny type. * We can do this as all deny entries come first, followed by * all allow entries (we have mandated this before accepting this acl). */ print_canon_ace_list( "file ace - before merge", file_ace); merge_aces( &file_ace ); print_canon_ace_list( "dir ace - before merge", dir_ace); merge_aces( &dir_ace ); /* * NT ACLs are order dependent. Go through the acl lists and * process DENY entries by masking the allow entries. */ print_canon_ace_list( "file ace - before deny", file_ace); process_deny_list( &file_ace); print_canon_ace_list( "dir ace - before deny", dir_ace); process_deny_list( &dir_ace); /* * A well formed POSIX file or default ACL has at least 3 entries, a * SMB_ACL_USER_OBJ, SMB_ACL_GROUP_OBJ, SMB_ACL_OTHER_OBJ * and optionally a mask entry. Ensure this is the case. */ print_canon_ace_list( "file ace - before valid", file_ace); if (!ensure_canon_entry_valid(&file_ace, fsp, pfile_owner_sid, pfile_grp_sid, pst, False)) { free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); return False; } print_canon_ace_list( "dir ace - before valid", dir_ace); if (dir_ace && !ensure_canon_entry_valid(&dir_ace, fsp, pfile_owner_sid, pfile_grp_sid, pst, True)) { free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); return False; } print_canon_ace_list( "file ace - return", file_ace); print_canon_ace_list( "dir ace - return", dir_ace); *ppfile_ace = file_ace; *ppdir_ace = dir_ace; return True; } /**************************************************************************** Map POSIX ACL perms to canon_ace permissions (a mode_t containing only S_(R|W|X)USR bits). ****************************************************************************/ static mode_t convert_permset_to_mode_t(SMB_ACL_PERMSET_T permset) { mode_t ret = 0; ret |= (sys_acl_get_perm(permset, SMB_ACL_READ) ? S_IRUSR : 0); ret |= (sys_acl_get_perm(permset, SMB_ACL_WRITE) ? S_IWUSR : 0); ret |= (sys_acl_get_perm(permset, SMB_ACL_EXECUTE) ? S_IXUSR : 0); return ret; } /**************************************************************************** Map generic UNIX permissions to canon_ace permissions (a mode_t containing only S_(R|W|X)USR bits). ****************************************************************************/ static mode_t unix_perms_to_acl_perms(mode_t mode, int r_mask, int w_mask, int x_mask) { mode_t ret = 0; if (mode & r_mask) ret |= S_IRUSR; if (mode & w_mask) ret |= S_IWUSR; if (mode & x_mask) ret |= S_IXUSR; return ret; } /**************************************************************************** Map canon_ace permissions (a mode_t containing only S_(R|W|X)USR bits) to an SMB_ACL_PERMSET_T. ****************************************************************************/ static int map_acl_perms_to_permset(mode_t mode, SMB_ACL_PERMSET_T *p_permset) { if (sys_acl_clear_perms(*p_permset) == -1) return -1; if (mode & S_IRUSR) { if (sys_acl_add_perm(*p_permset, SMB_ACL_READ) == -1) return -1; } if (mode & S_IWUSR) { if (sys_acl_add_perm(*p_permset, SMB_ACL_WRITE) == -1) return -1; } if (mode & S_IXUSR) { if (sys_acl_add_perm(*p_permset, SMB_ACL_EXECUTE) == -1) return -1; } return 0; } /****************************************************************************** When returning permissions, try and fit NT display semantics if possible. Note the the canon_entries here must have been malloced. The list format should be - first entry = owner, followed by group and other user entries, last entry = other. Note that this doesn't exactly match the NT semantics for an ACL. As POSIX entries are not ordered, and match on the most specific entry rather than walking a list, then a simple POSIX permission of rw-r--r-- should really map to 6 entries, Entry 0: owner : deny all except read and write. Entry 1: group : deny all except read. Entry 2: Everyone : deny all except read. Entry 3: owner : allow read and write. Entry 4: group : allow read. Entry 5: Everyone : allow read. But NT cannot display this in their ACL editor ! ********************************************************************************/ static void arrange_posix_perms( char *filename, canon_ace **pp_list_head) { extern DOM_SID global_sid_World; canon_ace *list_head = *pp_list_head; canon_ace *owner_ace = NULL; canon_ace *other_ace = NULL; canon_ace *ace = NULL; mode_t owner_perms = 0; mode_t group_perms = 0; mode_t other_perms = 0; for (ace = list_head; ace; ace = ace->next) { if (ace->type == SMB_ACL_USER_OBJ) owner_ace = ace; else if (ace->type == SMB_ACL_OTHER) { /* Last ace - this is "other" */ other_ace = ace; } else { /* Get the union of all the group and supplementary user perms. */ group_perms |= ace->perms; } } if (!owner_ace || !other_ace) { DEBUG(0,("arrange_posix_perms: Invalid POSIX permissions for file %s, missing owner or other.\n", filename )); return; } /* * The POSIX algorithm applies to owner first, and other last, * so ensure they are arranged in this order. */ if (owner_ace) { DLIST_PROMOTE(list_head, owner_ace); } if (other_ace) { DLIST_DEMOTE(list_head, other_ace, ace); } owner_perms = owner_ace->perms; other_perms = other_ace->perms; /* * We have to be clever here. NT4.x won't display anything other * Than an "Everyone, No access" DENY acl. Truncate blank perms * from the end, but we can't truncate blank permissions from * anywhere except the end, as they have an effect on allowing access * under POSIX. */ if ((owner_perms || group_perms) && !other_perms) { DLIST_REMOVE(list_head, other_ace); safe_free(other_ace); } if (owner_perms && !group_perms && !other_perms) { /* Free everything except the list head. */ free_canon_ace_list(owner_ace->next); owner_ace->next = NULL; } if (!owner_perms && !group_perms && !other_perms) { /* * Special case - no one has any access. * Return a 1 element ACL - other has "no access". */ if (owner_ace->next) { free_canon_ace_list(owner_ace->next); owner_ace->next = NULL; } owner_ace->type = SMB_ACL_OTHER; owner_ace->sid = global_sid_World; owner_ace->unix_ug.world = -1; owner_ace->owner_type = WORLD_ACE; owner_ace->attr = DENY_ACE; owner_ace->perms = 0; } /* We have probably changed the head of the list. */ *pp_list_head = list_head; } /****************************************************************************** Fall back to the generic 3 element UNIX permissions. ********************************************************************************/ static canon_ace *unix_canonicalise_acl(files_struct *fsp, SMB_STRUCT_STAT *psbuf, DOM_SID *powner, DOM_SID *pgroup, BOOL default_acl) { extern DOM_SID global_sid_World; canon_ace *list_head = NULL; canon_ace *owner_ace = NULL; canon_ace *group_ace = NULL; canon_ace *other_ace = NULL; mode_t mode; if (default_acl) return NULL; /* * Create 3 linked list entries. */ if ((owner_ace = (canon_ace *)malloc(sizeof(canon_ace))) == NULL) goto fail; if ((group_ace = (canon_ace *)malloc(sizeof(canon_ace))) == NULL) goto fail; if ((other_ace = (canon_ace *)malloc(sizeof(canon_ace))) == NULL) goto fail; ZERO_STRUCTP(owner_ace); ZERO_STRUCTP(group_ace); ZERO_STRUCTP(other_ace); owner_ace->type = SMB_ACL_USER_OBJ; owner_ace->sid = *powner; owner_ace->unix_ug.uid = psbuf->st_uid; owner_ace->owner_type = UID_ACE; owner_ace->attr = ALLOW_ACE; group_ace->type = SMB_ACL_GROUP_OBJ; group_ace->sid = *pgroup; group_ace->unix_ug.gid = psbuf->st_gid; group_ace->owner_type = GID_ACE; group_ace->attr = ALLOW_ACE; other_ace->type = SMB_ACL_OTHER; other_ace->sid = global_sid_World; other_ace->unix_ug.world = -1; other_ace->owner_type = WORLD_ACE; other_ace->attr = ALLOW_ACE; mode = psbuf->st_mode; owner_ace->perms = unix_perms_to_acl_perms(mode, S_IRUSR, S_IWUSR, S_IXUSR); owner_ace->attr = owner_ace->perms ? ALLOW_ACE : DENY_ACE; group_ace->perms = unix_perms_to_acl_perms(mode, S_IRGRP, S_IWGRP, S_IXGRP); group_ace->attr = group_ace->perms ? ALLOW_ACE : DENY_ACE; other_ace->perms = unix_perms_to_acl_perms(mode, S_IROTH, S_IWOTH, S_IXOTH); other_ace->attr = other_ace->perms ? ALLOW_ACE : DENY_ACE; DLIST_ADD(list_head, other_ace); DLIST_ADD(list_head, group_ace); DLIST_ADD(list_head, owner_ace); arrange_posix_perms(fsp->fsp_name,&list_head ); return list_head; fail: safe_free(owner_ace); safe_free(group_ace); safe_free(other_ace); return NULL; } /**************************************************************************** Create a linked list of canonical ACE entries. ****************************************************************************/ static canon_ace *canonicalise_acl( files_struct *fsp, SMB_ACL_T posix_acl, SMB_STRUCT_STAT *psbuf, DOM_SID *powner, DOM_SID *pgroup, BOOL default_acl) { extern DOM_SID global_sid_World; mode_t acl_mask = (S_IRUSR|S_IWUSR|S_IXUSR); canon_ace *list_head = NULL; canon_ace *ace = NULL; canon_ace *next_ace = NULL; int entry_id = SMB_ACL_FIRST_ENTRY; SMB_ACL_ENTRY_T entry; size_t ace_count; if (posix_acl == NULL) return unix_canonicalise_acl( fsp, psbuf, powner, pgroup, default_acl); while ( sys_acl_get_entry(posix_acl, entry_id, &entry) == 1) { SMB_ACL_TAG_T tagtype; SMB_ACL_PERMSET_T permset; DOM_SID sid; posix_id unix_ug; enum ace_owner owner_type; /* get_next... */ if (entry_id == SMB_ACL_FIRST_ENTRY) entry_id = SMB_ACL_NEXT_ENTRY; /* Is this a MASK entry ? */ if (sys_acl_get_tag_type(entry, &tagtype) == -1) continue; if (sys_acl_get_permset(entry, &permset) == -1) continue; /* Decide which SID to use based on the ACL type. */ switch(tagtype) { case SMB_ACL_USER_OBJ: /* Get the SID from the owner. */ uid_to_sid( &sid, psbuf->st_uid ); unix_ug.uid = psbuf->st_uid; owner_type = UID_ACE; break; case SMB_ACL_USER: { uid_t *puid = (uid_t *)sys_acl_get_qualifier(entry); if (puid == NULL) { DEBUG(0,("canonicalise_acl: Failed to get uid.\n")); continue; } uid_to_sid( &sid, *puid); unix_ug.uid = *puid; owner_type = UID_ACE; break; } case SMB_ACL_GROUP_OBJ: /* Get the SID from the owning group. */ gid_to_sid( &sid, psbuf->st_gid ); unix_ug.gid = psbuf->st_gid; owner_type = GID_ACE; break; case SMB_ACL_GROUP: { gid_t *pgid = (gid_t *)sys_acl_get_qualifier(entry); if (pgid == NULL) { DEBUG(0,("canonicalise_acl: Failed to get gid.\n")); continue; } gid_to_sid( &sid, *pgid); unix_ug.gid = *pgid; owner_type = GID_ACE; break; } case SMB_ACL_MASK: acl_mask = convert_permset_to_mode_t(permset); continue; /* Don't count the mask as an entry. */ case SMB_ACL_OTHER: /* Use the Everyone SID */ sid = global_sid_World; unix_ug.world = -1; owner_type = WORLD_ACE; break; default: DEBUG(0,("canonicalise_acl: Unknown tagtype %u\n", (unsigned int)tagtype)); continue; } /* * Add this entry to the list. */ if ((ace = (canon_ace *)malloc(sizeof(canon_ace))) == NULL) goto fail; ZERO_STRUCTP(ace); ace->type = tagtype; ace->perms = convert_permset_to_mode_t(permset); ace->attr = ALLOW_ACE; ace->sid = sid; ace->unix_ug = unix_ug; ace->owner_type = owner_type; DLIST_ADD(list_head, ace); } arrange_posix_perms(fsp->fsp_name,&list_head ); /* * Now go through the list, masking the permissions with the * acl_mask. Ensure all DENY Entries are at the start of the list. */ DEBUG(10,("canonicalize_acl: ace entries before arrange :\n")); for ( ace_count = 0, ace = list_head; ace; ace = next_ace, ace_count++) { next_ace = ace->next; /* Masks are only applied to entries other than USER_OBJ and OTHER. */ if (ace->type != SMB_ACL_OTHER && ace->type != SMB_ACL_USER_OBJ) ace->perms &= acl_mask; if (ace->perms == 0) { DLIST_PROMOTE(list_head, ace); } if( DEBUGLVL( 10 ) ) { print_canon_ace(ace, ace_count); } } print_canon_ace_list( "canonicalize_acl: ace entries after arrange", list_head ); return list_head; fail: free_canon_ace_list(list_head); return NULL; } /**************************************************************************** Attempt to apply an ACL to a file or directory. ****************************************************************************/ static BOOL set_canon_ace_list(files_struct *fsp, canon_ace *the_ace, BOOL default_ace, BOOL *pacl_set_support) { BOOL ret = False; SMB_ACL_T the_acl = sys_acl_init((int)count_canon_ace_list(the_ace) + 1); canon_ace *p_ace; int i; SMB_ACL_ENTRY_T mask_entry; SMB_ACL_PERMSET_T mask_permset; SMB_ACL_TYPE_T the_acl_type = (default_ace ? SMB_ACL_TYPE_DEFAULT : SMB_ACL_TYPE_ACCESS); if (the_acl == NULL) { if (errno != ENOSYS) { /* * Only print this error message if we have some kind of ACL * support that's not working. Otherwise we would always get this. */ DEBUG(0,("set_canon_ace_list: Unable to init %s ACL. (%s)\n", default_ace ? "default" : "file", strerror(errno) )); } *pacl_set_support = False; return False; } for (i = 0, p_ace = the_ace; p_ace; p_ace = p_ace->next, i++ ) { SMB_ACL_ENTRY_T the_entry; SMB_ACL_PERMSET_T the_permset; /* * Get the entry for this ACE. */ if (sys_acl_create_entry( &the_acl, &the_entry) == -1) { DEBUG(0,("set_canon_ace_list: Failed to create entry %d. (%s)\n", i, strerror(errno) )); goto done; } /* * Ok - we now know the ACL calls should be working, don't * allow fallback to chmod. */ *pacl_set_support = True; /* * Initialise the entry from the canon_ace. */ /* * First tell the entry what type of ACE this is. */ if (sys_acl_set_tag_type(the_entry, p_ace->type) == -1) { DEBUG(0,("set_canon_ace_list: Failed to set tag type on entry %d. (%s)\n", i, strerror(errno) )); goto done; } /* * Only set the qualifier (user or group id) if the entry is a user * or group id ACE. */ if ((p_ace->type == SMB_ACL_USER) || (p_ace->type == SMB_ACL_GROUP)) { if (sys_acl_set_qualifier(the_entry,(void *)&p_ace->unix_ug.uid) == -1) { DEBUG(0,("set_canon_ace_list: Failed to set qualifier on entry %d. (%s)\n", i, strerror(errno) )); goto done; } } /* * Convert the mode_t perms in the canon_ace to a POSIX permset. */ if (sys_acl_get_permset(the_entry, &the_permset) == -1) { DEBUG(0,("set_canon_ace_list: Failed to get permset on entry %d. (%s)\n", i, strerror(errno) )); goto done; } if (map_acl_perms_to_permset(p_ace->perms, &the_permset) == -1) { DEBUG(0,("set_canon_ace_list: Failed to create permset for mode (%u) on entry %d. (%s)\n", p_ace->perms, i, strerror(errno) )); goto done; } /* * ..and apply them to the entry. */ if (sys_acl_set_permset(the_entry, the_permset) == -1) { DEBUG(0,("set_canon_ace_list: Failed to add permset on entry %d. (%s)\n", i, strerror(errno) )); goto done; } if( DEBUGLVL( 10 )) print_canon_ace( p_ace, i); } /* * Add in a mask of rwx. */ if (sys_acl_create_entry( &the_acl, &mask_entry) == -1) { DEBUG(0,("set_canon_ace_list: Failed to create mask entry. (%s)\n", strerror(errno) )); goto done; } if (sys_acl_set_tag_type(mask_entry, SMB_ACL_MASK) == -1) { DEBUG(0,("set_canon_ace_list: Failed to set tag type on mask entry. (%s)\n",strerror(errno) )); goto done; } if (sys_acl_get_permset(mask_entry, &mask_permset) == -1) { DEBUG(0,("set_canon_ace_list: Failed to get mask permset. (%s)\n", strerror(errno) )); goto done; } if (map_acl_perms_to_permset(S_IRUSR|S_IWUSR|S_IXUSR, &mask_permset) == -1) { DEBUG(0,("set_canon_ace_list: Failed to create mask permset. (%s)\n", strerror(errno) )); goto done; } if (sys_acl_set_permset(mask_entry, mask_permset) == -1) { DEBUG(0,("set_canon_ace_list: Failed to add mask permset. (%s)\n", strerror(errno) )); goto done; } /* * Check if the ACL is valid. */ if (sys_acl_valid(the_acl) == -1) { DEBUG(0,("set_canon_ace_list: ACL type (%s) is invalid for set (%s).\n", the_acl_type == SMB_ACL_TYPE_DEFAULT ? "directory default" : "file", strerror(errno) )); goto done; } /* * Finally apply it to the file or directory. */ if(default_ace || fsp->is_directory || fsp->fd == -1) { if (sys_acl_set_file(dos_to_unix(fsp->fsp_name,False), the_acl_type, the_acl) == -1) { DEBUG(0,("set_canon_ace_list: sys_acl_set_file type %s failed for file %s (%s).\n", the_acl_type == SMB_ACL_TYPE_DEFAULT ? "directory default" : "file", fsp->fsp_name, strerror(errno) )); goto done; } } else { if (sys_acl_set_fd(fsp->fd, the_acl) == -1) { DEBUG(0,("set_canon_ace_list: sys_acl_set_file failed for file %s (%s).\n", fsp->fsp_name, strerror(errno) )); goto done; } } ret = True; done: if (the_acl != NULL) sys_acl_free_acl(the_acl); return ret; } /**************************************************************************** Convert a canon_ace to a generic 3 element permission - if possible. ****************************************************************************/ #define MAP_PERM(p,mask,result) (((p) & (mask)) ? (result) : 0 ) static BOOL convert_canon_ace_to_posix_perms( files_struct *fsp, canon_ace *file_ace_list, mode_t *posix_perms) { size_t ace_count = count_canon_ace_list(file_ace_list); canon_ace *ace_p; canon_ace *owner_ace = NULL; canon_ace *group_ace = NULL; canon_ace *other_ace = NULL; if (ace_count != 3) { DEBUG(3,("convert_canon_ace_to_posix_perms: Too many ACE entries for file %s to convert to \ posix perms.\n", fsp->fsp_name )); return False; } for (ace_p = file_ace_list; ace_p; ace_p = ace_p->next) { if (ace_p->owner_type == UID_ACE) owner_ace = ace_p; else if (ace_p->owner_type == GID_ACE) group_ace = ace_p; else if (ace_p->owner_type == WORLD_ACE) other_ace = ace_p; } if (!owner_ace || !group_ace || !other_ace) { DEBUG(3,("convert_canon_ace_to_posix_perms: Can't get standard entries for file %s.\n", fsp->fsp_name )); return False; } *posix_perms = (mode_t)0; *posix_perms |= owner_ace->perms; *posix_perms |= MAP_PERM(group_ace->perms, S_IRUSR, S_IRGRP); *posix_perms |= MAP_PERM(group_ace->perms, S_IWUSR, S_IWGRP); *posix_perms |= MAP_PERM(group_ace->perms, S_IXUSR, S_IXGRP); *posix_perms |= MAP_PERM(other_ace->perms, S_IRUSR, S_IROTH); *posix_perms |= MAP_PERM(other_ace->perms, S_IWUSR, S_IWOTH); *posix_perms |= MAP_PERM(other_ace->perms, S_IXUSR, S_IXOTH); /* The owner must have at least read access. */ if (*posix_perms == (mode_t)0) *posix_perms = S_IRUSR; DEBUG(10,("convert_canon_ace_to_posix_perms: converted u=%o,g=%o,w=%o to perm=0%o for file %s.\n", (int)owner_ace->perms, (int)group_ace->perms, (int)other_ace->perms, (int)*posix_perms, fsp->fsp_name )); return True; } static int nt_ace_comp( SEC_ACE *a1, SEC_ACE *a2) { if (a1->type == a2->type) return 0; if (a1->type == SEC_ACE_TYPE_ACCESS_DENIED && a2->type == SEC_ACE_TYPE_ACCESS_ALLOWED) return -1; return 1; } /**************************************************************************** Reply to query a security descriptor from an fsp. If it succeeds it allocates the space for the return elements and returns the size needed to return the security descriptor. This should be the only external function needed for the UNIX style get ACL. ****************************************************************************/ size_t get_nt_acl(files_struct *fsp, SEC_DESC **ppdesc) { SMB_STRUCT_STAT sbuf; SEC_ACE *nt_ace_list = NULL; DOM_SID owner_sid; DOM_SID group_sid; size_t sd_size = 0; SEC_ACL *psa = NULL; size_t num_acls = 0; size_t num_dir_acls = 0; size_t num_aces = 0; SMB_ACL_T posix_acl = NULL; SMB_ACL_T dir_acl = NULL; canon_ace *file_ace = NULL; canon_ace *dir_ace = NULL; *ppdesc = NULL; DEBUG(10,("get_nt_acl: called for file %s\n", fsp->fsp_name )); if(fsp->is_directory || fsp->fd == -1) { /* Get the stat struct for the owner info. */ if(vfs_stat(fsp->conn,fsp->fsp_name, &sbuf) != 0) { return 0; } /* * Get the ACL from the path. */ posix_acl = sys_acl_get_file( dos_to_unix(fsp->fsp_name, False), SMB_ACL_TYPE_ACCESS); /* * If it's a directory get the default POSIX ACL. */ if(fsp->is_directory) dir_acl = sys_acl_get_file( dos_to_unix(fsp->fsp_name, False), SMB_ACL_TYPE_DEFAULT); } else { /* Get the stat struct for the owner info. */ if(vfs_fstat(fsp,fsp->fd,&sbuf) != 0) { return 0; } /* * Get the ACL from the fd. */ posix_acl = sys_acl_get_fd(fsp->fd); } DEBUG(5,("get_nt_acl : file ACL %s, directory ACL %s\n", posix_acl ? "present" : "absent", dir_acl ? "present" : "absent" )); /* * Get the owner, group and world SIDs. */ create_file_sids(&sbuf, &owner_sid, &group_sid); /* Create the canon_ace lists. */ file_ace = canonicalise_acl( fsp, posix_acl, &sbuf, &owner_sid, &group_sid, False); num_acls = count_canon_ace_list(file_ace); /* We must have *some* ACLS. */ if (num_acls == 0) { DEBUG(0,("get_nt_acl : No ACLs on file (%s) !\n", fsp->fsp_name )); return 0; } if (fsp->is_directory) { dir_ace = canonicalise_acl(fsp, dir_acl, &sbuf, &owner_sid, &group_sid, True); num_dir_acls = count_canon_ace_list(dir_ace); } /* Allocate the ace list. */ if ((nt_ace_list = (SEC_ACE *)malloc((num_acls + num_dir_acls)* sizeof(SEC_ACE))) == NULL) { DEBUG(0,("get_nt_acl: Unable to malloc space for nt_ace_list.\n")); goto done; } memset(nt_ace_list, '\0', (num_acls + num_dir_acls) * sizeof(SEC_ACE) ); /* * Create the NT ACE list from the canonical ace lists. */ { canon_ace *ace; int nt_acl_type; int i; ace = file_ace; for (i = 0; i < num_acls; i++, ace = ace->next) { SEC_ACCESS acc = map_canon_ace_perms(&nt_acl_type, &owner_sid, ace ); init_sec_ace(&nt_ace_list[num_aces++], &ace->sid, nt_acl_type, acc, 0); } ace = dir_ace; for (i = 0; i < num_dir_acls; i++, ace = ace->next) { SEC_ACCESS acc = map_canon_ace_perms(&nt_acl_type, &owner_sid, ace ); init_sec_ace(&nt_ace_list[num_aces++], &ace->sid, nt_acl_type, acc, SEC_ACE_FLAG_OBJECT_INHERIT|SEC_ACE_FLAG_CONTAINER_INHERIT|SEC_ACE_FLAG_INHERIT_ONLY); } /* * Sort to force deny entries to the front. */ if (num_acls + num_dir_acls) qsort( nt_ace_list, num_acls + num_dir_acls, sizeof(nt_ace_list[0]), QSORT_CAST nt_ace_comp); } if (num_acls) { if((psa = make_sec_acl( main_loop_talloc_get(), ACL_REVISION, num_aces, nt_ace_list)) == NULL) { DEBUG(0,("get_nt_acl: Unable to malloc space for acl.\n")); goto done; } } *ppdesc = make_standard_sec_desc( main_loop_talloc_get(), &owner_sid, &group_sid, psa, &sd_size); if(!*ppdesc) { DEBUG(0,("get_nt_acl: Unable to malloc space for security descriptor.\n")); sd_size = 0; } done: if (posix_acl) sys_acl_free_acl(posix_acl); if (dir_acl) sys_acl_free_acl(dir_acl); free_canon_ace_list(file_ace); free_canon_ace_list(dir_ace); if (nt_ace_list) free(nt_ace_list); return sd_size; } /**************************************************************************** Reply to set a security descriptor on an fsp. security_info_sent is the description of the following NT ACL. This should be the only external function needed for the UNIX style set ACL. ****************************************************************************/ BOOL set_nt_acl(files_struct *fsp, uint32 security_info_sent, SEC_DESC *psd) { connection_struct *conn = fsp->conn; uid_t user = (uid_t)-1; gid_t grp = (gid_t)-1; SMB_STRUCT_STAT sbuf; DOM_SID file_owner_sid; DOM_SID file_grp_sid; canon_ace *file_ace_list = NULL; canon_ace *dir_ace_list = NULL; BOOL acl_perms = False; DEBUG(10,("set_nt_acl: called for file %s\n", fsp->fsp_name )); /* * Get the current state of the file. */ if(fsp->is_directory || fsp->fd == -1) { if(vfs_stat(fsp->conn,fsp->fsp_name, &sbuf) != 0) return False; } else { if(vfs_fstat(fsp,fsp->fd,&sbuf) != 0) return False; } /* * Unpack the user/group/world id's. */ if (!unpack_nt_owners( &sbuf, &user, &grp, security_info_sent, psd)) return False; /* * Do we need to chown ? */ if((user != (uid_t)-1 || grp != (uid_t)-1) && (sbuf.st_uid != user || sbuf.st_gid != grp)) { DEBUG(3,("set_nt_acl: chown %s. uid = %u, gid = %u.\n", fsp->fsp_name, (unsigned int)user, (unsigned int)grp )); if(vfs_chown( fsp->conn, fsp->fsp_name, user, grp) == -1) { DEBUG(3,("set_nt_acl: chown %s, %u, %u failed. Error = %s.\n", fsp->fsp_name, (unsigned int)user, (unsigned int)grp, strerror(errno) )); return False; } /* * Recheck the current state of the file, which may have changed. * (suid/sgid bits, for instance) */ if(fsp->is_directory) { if(vfs_stat(fsp->conn, fsp->fsp_name, &sbuf) != 0) { return False; } } else { int ret; if(fsp->fd == -1) ret = vfs_stat(fsp->conn, fsp->fsp_name, &sbuf); else ret = vfs_fstat(fsp,fsp->fd,&sbuf); if(ret != 0) return False; } } create_file_sids(&sbuf, &file_owner_sid, &file_grp_sid); acl_perms = unpack_canon_ace( fsp, &sbuf, &file_owner_sid, &file_grp_sid, &file_ace_list, &dir_ace_list, security_info_sent, psd); if ((file_ace_list == NULL) && (dir_ace_list == NULL)) { /* W2K traverse DACL set - ignore. */ return True; } if (!acl_perms) { DEBUG(3,("set_nt_acl: cannot set permissions\n")); free_canon_ace_list(file_ace_list); free_canon_ace_list(dir_ace_list); return False; } /* * Only change security if we got a DACL. */ if((security_info_sent & DACL_SECURITY_INFORMATION) && (psd->dacl != NULL)) { BOOL acl_set_support = False; BOOL ret = False; /* * Try using the POSIX ACL set first. Fall back to chmod if * we have no ACL support on this filesystem. */ if (acl_perms && file_ace_list) { ret = set_canon_ace_list(fsp, file_ace_list, False, &acl_set_support); if (acl_set_support && ret == False) { DEBUG(3,("set_nt_acl: failed to set file acl on file %s (%s).\n", fsp->fsp_name, strerror(errno) )); free_canon_ace_list(file_ace_list); free_canon_ace_list(dir_ace_list); return False; } } if (acl_perms && acl_set_support && fsp->is_directory && dir_ace_list) { if (!set_canon_ace_list(fsp, dir_ace_list, True, &acl_set_support)) { DEBUG(3,("set_nt_acl: failed to set default acl on directory %s (%s).\n", fsp->fsp_name, strerror(errno) )); free_canon_ace_list(file_ace_list); free_canon_ace_list(dir_ace_list); return False; } } /* * If we cannot set using POSIX ACLs we fall back to checking if we need to chmod. */ if(!acl_set_support && acl_perms) { mode_t posix_perms; if (!convert_canon_ace_to_posix_perms( fsp, file_ace_list, &posix_perms)) { free_canon_ace_list(file_ace_list); free_canon_ace_list(dir_ace_list); DEBUG(3,("set_nt_acl: failed to convert file acl to posix permissions for file %s.\n", fsp->fsp_name )); return False; } if (sbuf.st_mode != posix_perms) { DEBUG(3,("set_nt_acl: chmod %s. perms = 0%o.\n", fsp->fsp_name, (unsigned int)posix_perms )); if(conn->vfs_ops.chmod(conn,dos_to_unix(fsp->fsp_name, False), posix_perms) == -1) { DEBUG(3,("set_nt_acl: chmod %s, 0%o failed. Error = %s.\n", fsp->fsp_name, (unsigned int)posix_perms, strerror(errno) )); free_canon_ace_list(file_ace_list); free_canon_ace_list(dir_ace_list); return False; } } } } free_canon_ace_list(file_ace_list); free_canon_ace_list(dir_ace_list); return True; } /**************************************************************************** Do a chmod by setting the ACL USER_OBJ, GROUP_OBJ and OTHER bits in an ACL and set the mask to rwx. Needed to preserve complex ACLs set by NT. ****************************************************************************/ static int chmod_acl_internals( SMB_ACL_T posix_acl, mode_t mode) { int entry_id = SMB_ACL_FIRST_ENTRY; SMB_ACL_ENTRY_T entry; int num_entries = 0; while ( sys_acl_get_entry(posix_acl, entry_id, &entry) == 1) { SMB_ACL_TAG_T tagtype; SMB_ACL_PERMSET_T permset; mode_t perms; /* get_next... */ if (entry_id == SMB_ACL_FIRST_ENTRY) entry_id = SMB_ACL_NEXT_ENTRY; if (sys_acl_get_tag_type(entry, &tagtype) == -1) return -1; if (sys_acl_get_permset(entry, &permset) == -1) return -1; num_entries++; switch(tagtype) { case SMB_ACL_USER_OBJ: perms = unix_perms_to_acl_perms(mode, S_IRUSR, S_IWUSR, S_IXUSR); break; case SMB_ACL_GROUP_OBJ: perms = unix_perms_to_acl_perms(mode, S_IRGRP, S_IWGRP, S_IXGRP); break; case SMB_ACL_MASK: perms = S_IRUSR|S_IWUSR|S_IXUSR; break; case SMB_ACL_OTHER: perms = unix_perms_to_acl_perms(mode, S_IROTH, S_IWOTH, S_IXOTH); break; default: continue; } if (map_acl_perms_to_permset(perms, &permset) == -1) return -1; if (sys_acl_set_permset(entry, permset) == -1) return -1; } /* * If this is a simple 3 element ACL then it's a standard * UNIX permission set. Just use chmod... */ if (num_entries == 3) return -1; return 0; } /**************************************************************************** Do a chmod by setting the ACL USER_OBJ, GROUP_OBJ and OTHER bits in an ACL and set the mask to rwx. Needed to preserve complex ACLs set by NT. Note that name is in UNIX character set. ****************************************************************************/ int chmod_acl(char *name, mode_t mode) { SMB_ACL_T posix_acl = NULL; int ret = -1; if ((posix_acl = sys_acl_get_file(name, SMB_ACL_TYPE_ACCESS)) == NULL) return -1; if ((ret = chmod_acl_internals(posix_acl, mode)) == -1) goto done; ret = sys_acl_set_file(name, SMB_ACL_TYPE_ACCESS, posix_acl); done: sys_acl_free_acl(posix_acl); return ret; } /**************************************************************************** Do an fchmod by setting the ACL USER_OBJ, GROUP_OBJ and OTHER bits in an ACL and set the mask to rwx. Needed to preserve complex ACLs set by NT. ****************************************************************************/ int fchmod_acl(int fd, mode_t mode) { SMB_ACL_T posix_acl = NULL; int ret = -1; if ((posix_acl = sys_acl_get_fd(fd)) == NULL) return -1; if ((ret = chmod_acl_internals(posix_acl, mode)) == -1) goto done; ret = sys_acl_set_fd(fd, posix_acl); done: sys_acl_free_acl(posix_acl); return ret; }