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-rw-r--r--source3/smbd/posix_acls.c618
1 files changed, 618 insertions, 0 deletions
diff --git a/source3/smbd/posix_acls.c b/source3/smbd/posix_acls.c
new file mode 100644
index 0000000000..b463ec2479
--- /dev/null
+++ b/source3/smbd/posix_acls.c
@@ -0,0 +1,618 @@
+#ifdef HAVE_POSIX_ACLS
+#define OLD_NTDOMAIN 1
+/*
+ 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"
+
+/****************************************************************************
+ 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 );
+}
+
+/****************************************************************************
+ Map unix perms to NT.
+****************************************************************************/
+
+static SEC_ACCESS map_unix_perms( int *pacl_type, mode_t perm, int r_mask, int w_mask, int x_mask, BOOL is_directory)
+{
+ SEC_ACCESS sa;
+ uint32 nt_mask = 0;
+
+ *pacl_type = SEC_ACE_TYPE_ACCESS_ALLOWED;
+
+ if((perm & (r_mask|w_mask|x_mask)) == (r_mask|w_mask|x_mask)) {
+ nt_mask = UNIX_ACCESS_RWX;
+ } else if((perm & (r_mask|w_mask|x_mask)) == 0) {
+ nt_mask = UNIX_ACCESS_NONE;
+ } else {
+ nt_mask |= (perm & r_mask) ? UNIX_ACCESS_R : 0;
+ if(is_directory)
+ nt_mask |= (perm & w_mask) ? UNIX_ACCESS_W : 0;
+ else
+ nt_mask |= (perm & w_mask) ? UNIX_ACCESS_W : 0;
+ nt_mask |= (perm & x_mask) ? UNIX_ACCESS_X : 0;
+ }
+ init_sec_access(&sa,nt_mask);
+ return sa;
+}
+
+/****************************************************************************
+ Validate a SID.
+****************************************************************************/
+
+static BOOL validate_unix_sid( DOM_SID *psid, uint32 *prid, DOM_SID *sd_sid)
+{
+ extern DOM_SID global_sam_sid;
+ DOM_SID sid;
+
+ if(!sd_sid) {
+ DEBUG(5,("validate_unix_sid: sid missing.\n"));
+ return False;
+ }
+
+ sid_copy(psid, sd_sid);
+ sid_copy(&sid, sd_sid);
+
+ if(!sid_split_rid(&sid, prid)) {
+ DEBUG(5,("validate_unix_sid: cannot get RID from sid.\n"));
+ return False;
+ }
+
+ if(!sid_equal( &sid, &global_sam_sid)) {
+ DEBUG(5,("validate_unix_sid: sid is not ours.\n"));
+ return False;
+ }
+
+ return True;
+}
+
+/****************************************************************************
+ Map NT perms to UNIX.
+****************************************************************************/
+
+#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 owner, group and set of UNIX permissions.
+****************************************************************************/
+
+static BOOL unpack_nt_permissions(SMB_STRUCT_STAT *psbuf, uid_t *puser, gid_t *pgrp, mode_t *pmode,
+ uint32 security_info_sent, SEC_DESC *psd, BOOL is_directory)
+{
+ extern DOM_SID global_sid_World;
+ DOM_SID owner_sid;
+ DOM_SID grp_sid;
+ DOM_SID file_owner_sid;
+ DOM_SID file_grp_sid;
+ uint32 owner_rid;
+ uint32 grp_rid;
+ SEC_ACL *dacl = psd->dacl;
+ BOOL all_aces_are_inherit_only = (is_directory ? True : False);
+ int i;
+ enum SID_NAME_USE sid_type;
+
+ *pmode = 0;
+ *puser = (uid_t)-1;
+ *pgrp = (gid_t)-1;
+
+ if(security_info_sent == 0) {
+ DEBUG(0,("unpack_nt_permissions: no security info sent !\n"));
+ return False;
+ }
+
+ /*
+ * Windows 2000 sends the owner and group SIDs as the logged in
+ * user, not the connected user. But it still sends the file
+ * owner SIDs on an ACL set. So we need to check for the file
+ * owner and group SIDs as well as the owner SIDs. JRA.
+ */
+
+ create_file_sids(psbuf, &file_owner_sid, &file_grp_sid);
+
+ /*
+ * 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_permissions: validating owner_sid.\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) {
+ if (!sid_to_uid( &owner_sid, puser, &sid_type))
+ DEBUG(3,("unpack_nt_permissions: 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) {
+ if (!sid_to_gid( &grp_sid, pgrp, &sid_type))
+ DEBUG(3,("unpack_nt_permissions: unable to validate group sid.\n"));
+ }
+
+ /*
+ * If no DACL then this is a chown only security descriptor.
+ */
+
+ if(!(security_info_sent & DACL_SECURITY_INFORMATION) || !dacl) {
+ *pmode = 0;
+ return True;
+ }
+
+ /*
+ * Now go through the DACL and ensure that
+ * any owner/group sids match.
+ */
+
+ for(i = 0; i < dacl->num_aces; i++) {
+ DOM_SID ace_sid;
+ SEC_ACE *psa = &dacl->ace[i];
+
+ if((psa->type != SEC_ACE_TYPE_ACCESS_ALLOWED) &&
+ (psa->type != SEC_ACE_TYPE_ACCESS_DENIED)) {
+ DEBUG(3,("unpack_nt_permissions: unable to set anything but an ALLOW or DENY ACE.\n"));
+ return False;
+ }
+
+ /*
+ * Ignore or remove bits we don't care about on a directory ACE.
+ */
+
+ if(is_directory) {
+ if(psa->flags & SEC_ACE_FLAG_INHERIT_ONLY) {
+ DEBUG(3,("unpack_nt_permissions: ignoring inherit only ACE.\n"));
+ continue;
+ }
+
+ /*
+ * At least one of the ACE entries wasn't inherit only.
+ * Flag this so we know the returned mode is valid.
+ */
+
+ all_aces_are_inherit_only = False;
+ }
+
+ /*
+ * Windows 2000 sets these flags even on *file* ACE's. This is wrong
+ * but we can ignore them for now. Revisit this when we go to POSIX
+ * ACLs on directories.
+ */
+
+ psa->flags &= ~(SEC_ACE_FLAG_OBJECT_INHERIT|SEC_ACE_FLAG_CONTAINER_INHERIT);
+
+ if(psa->flags != 0) {
+ DEBUG(1,("unpack_nt_permissions: unable to set ACE flags (%x).\n",
+ (unsigned int)psa->flags));
+ 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;
+
+ sid_copy(&ace_sid, &psa->sid);
+
+ if(sid_equal(&ace_sid, &file_owner_sid)) {
+ /*
+ * Map the desired permissions into owner perms.
+ */
+
+ if(psa->type == SEC_ACE_TYPE_ACCESS_ALLOWED)
+ *pmode |= map_nt_perms( psa->info, S_IRUSR);
+ else
+ *pmode &= ~(map_nt_perms( psa->info, S_IRUSR));
+
+ } else if( sid_equal(&ace_sid, &file_grp_sid)) {
+ /*
+ * Map the desired permissions into group perms.
+ */
+
+ if(psa->type == SEC_ACE_TYPE_ACCESS_ALLOWED)
+ *pmode |= map_nt_perms( psa->info, S_IRGRP);
+ else
+ *pmode &= ~(map_nt_perms( psa->info, S_IRGRP));
+
+ } else if( sid_equal(&ace_sid, &global_sid_World)) {
+ /*
+ * Map the desired permissions into other perms.
+ */
+
+ if(psa->type == SEC_ACE_TYPE_ACCESS_ALLOWED)
+ *pmode |= map_nt_perms( psa->info, S_IROTH);
+ else
+ *pmode &= ~(map_nt_perms( psa->info, S_IROTH));
+
+ } else {
+ DEBUG(0,("unpack_nt_permissions: unknown SID used in ACL.\n"));
+ return False;
+ }
+ }
+
+ if (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,("unpack_nt_permissions: Win2k inherit acl traverse. Ignoring DACL.\n"));
+ free_sec_acl(&psd->dacl);
+ }
+
+ return True;
+}
+
+/****************************************************************************
+ Go through the ACL entries one by one, count them and extract the permset
+ of the mask entry as we scan the acl.
+****************************************************************************/
+
+size_t get_num_posix_entries(acl_t posix_acl, acl_permset_t *posix_mask)
+{
+ size_t num_entries;
+ acl_entry_t entry;
+ int entry_id = ACL_FIRST_ENTRY;
+
+ *posix_mask = (ACL_READ|ACL_WRITE|ACL_EXECUTE);
+
+ for( num_entries = 0; acl_get_entry(posix_acl, entry_id, &entry) != -1; num_entries++) {
+ acl_tag_t tagtype;
+ acl_permset_t permset;
+
+ entry_id = ACL_NEXT_ENTRY;
+ if (acl_get_tag_type(entry, &tagtype) == -1)
+ continue;
+
+ if (tagtype == ACL_MASK)
+ if (acl_get_permset(entry, &permset) == 0)
+ *posix_mask = permset;
+ }
+
+ return num_entries;
+}
+
+/****************************************************************************
+ 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)
+{
+ extern DOM_SID global_sid_World;
+ SMB_STRUCT_STAT sbuf;
+ SEC_ACE ace_list[6];
+ DOM_SID owner_sid;
+ DOM_SID group_sid;
+ size_t sd_size;
+ SEC_ACL *psa = NULL;
+ SEC_ACCESS owner_access;
+ int owner_acl_type;
+ SEC_ACCESS group_access;
+ int grp_acl_type;
+ SEC_ACCESS other_access;
+ int other_acl_type;
+ int num_acls = 0;
+ acl_t posix_acl;
+
+ *ppdesc = NULL;
+
+ if(fsp->is_directory || fsp->fd == -1) {
+ if(dos_stat(fsp->fsp_name, &sbuf) != 0) {
+ return 0;
+ }
+ /*
+ * Get the ACL from the path.
+ */
+
+ if ((posix_acl = acl_get_file( dos_to_unix(fsp->fsp_name, False), ACL_TYPE_ACCESS)) == NULL)
+ return 0;
+
+ } else {
+ if(fsp->conn->vfs_ops.fstat(fsp->fd,&sbuf) != 0) {
+ return 0;
+ }
+ /*
+ * Get the ACL from the fd.
+ */
+ if ((posix_acl = acl_get_fd( fsp->fd)) == NULL)
+ return 0;
+ }
+
+ /*
+ * Get the owner, group and world SIDs.
+ */
+
+ create_file_sids(&sbuf, &owner_sid, &group_sid);
+
+ /*
+ * Count the number of entries in the ACL and return
+ * the mask.
+ */
+
+ num_posix_entries = get_num_posix_entries(posix_acl, &posix_mask);
+
+ /*
+ * Create the generic 3 element UNIX acl.
+ */
+
+ owner_access = map_unix_perms(&owner_acl_type, sbuf.st_mode,
+ S_IRUSR, S_IWUSR, S_IXUSR, fsp->is_directory);
+ group_access = map_unix_perms(&grp_acl_type, sbuf.st_mode,
+ S_IRGRP, S_IWGRP, S_IXGRP, fsp->is_directory);
+ other_access = map_unix_perms(&other_acl_type, sbuf.st_mode,
+ S_IROTH, S_IWOTH, S_IXOTH, fsp->is_directory);
+
+ if(owner_access.mask)
+ init_sec_ace(&ace_list[num_acls++], &owner_sid, owner_acl_type, owner_access, 0);
+
+ if(group_access.mask)
+ init_sec_ace(&ace_list[num_acls++], &group_sid, grp_acl_type, group_access, 0);
+
+ if(other_access.mask)
+ init_sec_ace(&ace_list[num_acls++], &global_sid_World, other_acl_type, other_access, 0);
+
+ if(fsp->is_directory) {
+ /*
+ * For directory ACLs we also add in the inherited permissions
+ * ACE entries. These are the permissions a file would get when
+ * being created in the directory.
+ */
+ mode_t mode = unix_mode( fsp->conn, FILE_ATTRIBUTE_ARCHIVE, fsp->fsp_name);
+
+ owner_access = map_unix_perms(&owner_acl_type, mode,
+ S_IRUSR, S_IWUSR, S_IXUSR, fsp->is_directory);
+ group_access = map_unix_perms(&grp_acl_type, mode,
+ S_IRGRP, S_IWGRP, S_IXGRP, fsp->is_directory);
+ other_access = map_unix_perms(&other_acl_type, mode,
+ S_IROTH, S_IWOTH, S_IXOTH, fsp->is_directory);
+
+ if(owner_access.mask)
+ init_sec_ace(&ace_list[num_acls++], &owner_sid, owner_acl_type,
+ owner_access, SEC_ACE_FLAG_OBJECT_INHERIT|SEC_ACE_FLAG_INHERIT_ONLY);
+
+ if(group_access.mask)
+ init_sec_ace(&ace_list[num_acls++], &group_sid, grp_acl_type,
+ group_access, SEC_ACE_FLAG_OBJECT_INHERIT|SEC_ACE_FLAG_INHERIT_ONLY);
+
+ if(other_access.mask)
+ init_sec_ace(&ace_list[num_acls++], &global_sid_World, other_acl_type,
+ other_access, SEC_ACE_FLAG_OBJECT_INHERIT|SEC_ACE_FLAG_INHERIT_ONLY);
+ }
+
+ if(num_acls) {
+ if((psa = make_sec_acl( ACL_REVISION, num_acls, ace_list)) == NULL) {
+ DEBUG(0,("get_nt_acl: Unable to malloc space for acl.\n"));
+ return 0;
+ }
+ }
+
+ *ppdesc = make_standard_sec_desc( &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;
+ }
+
+ free_sec_acl(&psa);
+
+ 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;
+ mode_t perms = 0;
+ SMB_STRUCT_STAT sbuf;
+ BOOL got_dacl = False;
+
+ /*
+ * Get the current state of the file.
+ */
+
+ if(fsp->is_directory) {
+ if(dos_stat(fsp->fsp_name, &sbuf) != 0)
+ return False;
+ } else {
+
+ int ret;
+
+ if(fsp->fd == -1)
+ ret = conn->vfs_ops.stat(dos_to_unix(fsp->fsp_name,False), &sbuf);
+ else
+ ret = conn->vfs_ops.fstat(fsp->fd,&sbuf);
+
+ if(ret != 0)
+ return False;
+ }
+
+ /*
+ * Unpack the user/group/world id's and permissions.
+ */
+
+ if (!unpack_nt_permissions( &sbuf, &user, &grp, &perms, security_info_sent, psd, fsp->is_directory))
+ return False;
+
+ if (psd->dacl != NULL)
+ got_dacl = True;
+
+ /*
+ * Do we need to chown ?
+ */
+
+ if((user != (uid_t)-1 || grp != (uid_t)-1) && (sbuf.st_uid != user || sbuf.st_gid != grp)) {
+
+ DEBUG(3,("call_nt_transact_set_security_desc: chown %s. uid = %u, gid = %u.\n",
+ fsp->fsp_name, (unsigned int)user, (unsigned int)grp ));
+
+ if(dos_chown( fsp->fsp_name, user, grp) == -1) {
+ DEBUG(3,("call_nt_transact_set_security_desc: 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(dos_stat(fsp->fsp_name, &sbuf) != 0) {
+ return False;
+ }
+ } else {
+
+ int ret;
+
+ if(fsp->fd == -1)
+ ret = conn->vfs_ops.stat(dos_to_unix(fsp->fsp_name,False), &sbuf);
+ else
+ ret = conn->vfs_ops.fstat(fsp->fd,&sbuf);
+
+ if(ret != 0)
+ return False;
+ }
+ }
+
+ /*
+ * Only change security if we got a DACL.
+ */
+
+ if((security_info_sent & DACL_SECURITY_INFORMATION) && got_dacl) {
+
+ /*
+ * Check to see if we need to change anything.
+ * Enforce limits on modified bits *only*. Don't enforce masks
+ * on bits not changed by the user.
+ */
+
+ if(fsp->is_directory) {
+
+ perms &= (lp_dir_security_mask(SNUM(conn)) | sbuf.st_mode);
+ perms |= (lp_force_dir_security_mode(SNUM(conn)) & ( perms ^ sbuf.st_mode ));
+
+ } else {
+
+ perms &= (lp_security_mask(SNUM(conn)) | sbuf.st_mode);
+ perms |= (lp_force_security_mode(SNUM(conn)) & ( perms ^ sbuf.st_mode ));
+
+ }
+
+ /*
+ * Preserve special bits.
+ */
+
+ perms |= (sbuf.st_mode & ~0777);
+
+ /*
+ * Do we need to chmod ?
+ */
+
+ if(sbuf.st_mode != perms) {
+
+ DEBUG(3,("call_nt_transact_set_security_desc: chmod %s. perms = 0%o.\n",
+ fsp->fsp_name, (unsigned int)perms ));
+
+ if(conn->vfs_ops.chmod(dos_to_unix(fsp->fsp_name, False), perms) == -1) {
+ DEBUG(3,("call_nt_transact_set_security_desc: chmod %s, 0%o failed. Error = %s.\n",
+ fsp->fsp_name, (unsigned int)perms, strerror(errno) ));
+ return False;
+ }
+ }
+ }
+
+ return True;
+}
+#undef OLD_NTDOMAIN
+#else /* HAVE_POSIX_ACLS */
+ void dummy_posix_acls(void) {;} /* So some compilers don't complain. */
+#endif /* HAVE_POSIX_ACLS */