diff options
Diffstat (limited to 'source3/smbd')
| -rw-r--r-- | source3/smbd/open.c | 149 | ||||
| -rw-r--r-- | source3/smbd/posix_acls.c | 188 |
2 files changed, 228 insertions, 109 deletions
diff --git a/source3/smbd/open.c b/source3/smbd/open.c index 7c04cdbe7c..b13b4f2a6c 100644 --- a/source3/smbd/open.c +++ b/source3/smbd/open.c @@ -1403,6 +1403,8 @@ NTSTATUS open_file_ntcreate(connection_struct *conn, } if (!NT_STATUS_IS_OK(status)) { + uint32 can_access_mask; + BOOL can_access = True; SMB_ASSERT(NT_STATUS_EQUAL(status, NT_STATUS_SHARING_VIOLATION)); @@ -1434,29 +1436,20 @@ NTSTATUS open_file_ntcreate(connection_struct *conn, * MS-Access. If a file open will fail due to share * permissions and also for security (access) reasons, * we need to return the access failed error, not the - * share error. This means we must attempt to open the - * file anyway in order to get the UNIX access error - - * even if we're going to fail the open for share - * reasons. This is bad, as we're burning another fd - * if there are existing locks but there's nothing - * else we can do. We also ensure we're not going to - * create or tuncate the file as we only want an - * access decision at this stage. JRA. + * share error. We can't open the file due to kernel + * oplock deadlock (it's possible we failed above on + * the open_mode_check()) so use a userspace check. */ - errno = 0; - fsp_open = open_file(fsp,conn,fname,psbuf, - flags|(flags2&~(O_TRUNC|O_CREAT)), - unx_mode,access_mask); - - DEBUG(4,("open_file_ntcreate : share_mode deny - " - "calling open_file with flags=0x%X " - "flags2=0x%X mode=0%o returned %s\n", - flags, (flags2&~(O_TRUNC|O_CREAT)), - (unsigned int)unx_mode, nt_errstr(fsp_open))); - - if (!NT_STATUS_IS_OK(fsp_open) && errno) { - /* Default error. */ - status = NT_STATUS_ACCESS_DENIED; + + if (flags & O_RDWR) { + can_access_mask = FILE_READ_DATA|FILE_WRITE_DATA; + } else { + can_access_mask = FILE_READ_DATA; + } + + if (((flags & O_RDWR) && !CAN_WRITE(conn)) || + !can_access_file(conn,fname,psbuf,can_access_mask)) { + can_access = False; } /* @@ -1503,13 +1496,14 @@ NTSTATUS open_file_ntcreate(connection_struct *conn, } TALLOC_FREE(lck); - if (NT_STATUS_IS_OK(fsp_open)) { - fd_close(conn, fsp); + if (can_access) { /* * We have detected a sharing violation here * so return the correct error code */ status = NT_STATUS_SHARING_VIOLATION; + } else { + status = NT_STATUS_ACCESS_DENIED; } file_free(fsp); return status; @@ -1536,6 +1530,14 @@ NTSTATUS open_file_ntcreate(connection_struct *conn, (unsigned int)flags, (unsigned int)flags2, (unsigned int)unx_mode)); + /* Drop the lock before doing any real file access. Allows kernel + oplock breaks to be processed. Handle any races after the open + call when we re-acquire the lock. */ + + if (lck) { + TALLOC_FREE(lck); + } + /* * open_file strips any O_TRUNC flags itself. */ @@ -1551,70 +1553,65 @@ NTSTATUS open_file_ntcreate(connection_struct *conn, return fsp_open; } - if (!file_existed) { - - /* - * Deal with the race condition where two smbd's detect the - * file doesn't exist and do the create at the same time. One - * of them will win and set a share mode, the other (ie. this - * one) should check if the requested share mode for this - * create is allowed. - */ - - /* - * Now the file exists and fsp is successfully opened, - * fsp->dev and fsp->inode are valid and should replace the - * dev=0,inode=0 from a non existent file. Spotted by - * Nadav Danieli <nadavd@exanet.com>. JRA. - */ + /* + * Deal with the race condition where two smbd's detect the + * file doesn't exist and do the create at the same time. One + * of them will win and set a share mode, the other (ie. this + * one) should check if the requested share mode for this + * create is allowed. + */ - dev = fsp->dev; - inode = fsp->inode; + /* + * Now the file exists and fsp is successfully opened, + * fsp->dev and fsp->inode are valid and should replace the + * dev=0,inode=0 from a non existent file. Spotted by + * Nadav Danieli <nadavd@exanet.com>. JRA. + */ - lck = get_share_mode_lock(NULL, dev, inode, - conn->connectpath, - fname); + dev = fsp->dev; + inode = fsp->inode; - if (lck == NULL) { - DEBUG(0, ("open_file_ntcreate: Could not get share mode lock for %s\n", fname)); - fd_close(conn, fsp); - file_free(fsp); - return NT_STATUS_SHARING_VIOLATION; - } + lck = get_share_mode_lock(NULL, dev, inode, + conn->connectpath, + fname); - status = open_mode_check(conn, fname, lck, - access_mask, share_access, - create_options, &file_existed); + if (lck == NULL) { + DEBUG(0, ("open_file_ntcreate: Could not get share mode lock for %s\n", fname)); + fd_close(conn, fsp); + file_free(fsp); + return NT_STATUS_SHARING_VIOLATION; + } - if (!NT_STATUS_IS_OK(status)) { - struct deferred_open_record state; + status = open_mode_check(conn, fname, lck, + access_mask, share_access, + create_options, &file_existed); - fd_close(conn, fsp); - file_free(fsp); + if (!NT_STATUS_IS_OK(status)) { + struct deferred_open_record state; - state.delayed_for_oplocks = False; - state.dev = dev; - state.inode = inode; + fd_close(conn, fsp); + file_free(fsp); - /* Do it all over again immediately. In the second - * round we will find that the file existed and handle - * the DELETE_PENDING and FCB cases correctly. No need - * to duplicate the code here. Essentially this is a - * "goto top of this function", but don't tell - * anybody... */ + state.delayed_for_oplocks = False; + state.dev = dev; + state.inode = inode; - defer_open(lck, request_time, timeval_zero(), - &state); - TALLOC_FREE(lck); - return status; - } + /* Do it all over again immediately. In the second + * round we will find that the file existed and handle + * the DELETE_PENDING and FCB cases correctly. No need + * to duplicate the code here. Essentially this is a + * "goto top of this function", but don't tell + * anybody... */ - /* - * We exit this block with the share entry *locked*..... - */ + defer_open(lck, request_time, timeval_zero(), + &state); + TALLOC_FREE(lck); + return status; } - SMB_ASSERT(lck != NULL); + /* + * The share entry is again *locked*..... + */ /* note that we ignore failure for the following. It is basically a hack for NFS, and NFS will never set one of diff --git a/source3/smbd/posix_acls.c b/source3/smbd/posix_acls.c index 73744cf26e..d265057ac0 100644 --- a/source3/smbd/posix_acls.c +++ b/source3/smbd/posix_acls.c @@ -3911,7 +3911,7 @@ BOOL set_unix_posix_acl(connection_struct *conn, files_struct *fsp, const char * Return -1 if no match, 0 if match and denied, 1 if match and allowed. ****************************************************************************/ -static int check_posix_acl_group_write(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf) +static int check_posix_acl_group_access(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf, uint32 access_mask) { SMB_ACL_T posix_acl = NULL; int entry_id = SMB_ACL_FIRST_ENTRY; @@ -3922,17 +3922,21 @@ static int check_posix_acl_group_write(connection_struct *conn, const char *fnam int ret = -1; gid_t cu_gid; + DEBUG(10,("check_posix_acl_group_access: requesting 0x%x on file %s\n", + (unsigned int)access_mask, fname )); + if ((posix_acl = SMB_VFS_SYS_ACL_GET_FILE(conn, fname, SMB_ACL_TYPE_ACCESS)) == NULL) { goto check_stat; } - /* First ensure the group mask allows group read. */ + /* First ensure the group mask allows group access. */ /* Also check any user entries (these take preference over group). */ while ( SMB_VFS_SYS_ACL_GET_ENTRY(conn, posix_acl, entry_id, &entry) == 1) { SMB_ACL_TAG_T tagtype; SMB_ACL_PERMSET_T permset; int have_write = -1; + int have_read = -1; /* get_next... */ if (entry_id == SMB_ACL_FIRST_ENTRY) @@ -3946,6 +3950,11 @@ static int check_posix_acl_group_write(connection_struct *conn, const char *fnam goto check_stat; } + have_read = SMB_VFS_SYS_ACL_GET_PERM(conn, permset, SMB_ACL_READ); + if (have_read == -1) { + goto check_stat; + } + have_write = SMB_VFS_SYS_ACL_GET_PERM(conn, permset, SMB_ACL_WRITE); if (have_write == -1) { goto check_stat; @@ -3956,16 +3965,36 @@ static int check_posix_acl_group_write(connection_struct *conn, const char *fnam * canonicalize to 0 or 1. */ have_write = (have_write ? 1 : 0); + have_read = (have_read ? 1 : 0); switch(tagtype) { case SMB_ACL_MASK: seen_mask = True; - if (!have_write) { - /* We don't have any group or explicit user write permission. */ - ret = -1; /* Allow caller to check "other" permissions. */ - DEBUG(10,("check_posix_acl_group_write: file %s \ -refusing write due to mask.\n", fname)); - goto done; + switch (access_mask) { + case FILE_READ_DATA: + if (!have_read) { + ret = -1; + DEBUG(10,("check_posix_acl_group_access: file %s " + "refusing read due to mask.\n", fname)); + goto done; + } + break; + case FILE_WRITE_DATA: + if (!have_write) { + ret = -1; + DEBUG(10,("check_posix_acl_group_access: file %s " + "refusing write due to mask.\n", fname)); + goto done; + } + break; + default: /* FILE_READ_DATA|FILE_WRITE_DATA */ + if (!have_write || !have_read) { + ret = -1; + DEBUG(10,("check_posix_acl_group_access: file %s " + "refusing read/write due to mask.\n", fname)); + goto done; + } + break; } break; case SMB_ACL_USER: @@ -3977,9 +4006,21 @@ refusing write due to mask.\n", fname)); } if (current_user.ut.uid == *puid) { /* We have a uid match but we must ensure we have seen the acl mask. */ - ret = have_write; - DEBUG(10,("check_posix_acl_group_write: file %s \ -match on user %u -> %s.\n", fname, (unsigned int)*puid, ret ? "can write" : "cannot write")); + switch (access_mask) { + case FILE_READ_DATA: + ret = have_read; + break; + case FILE_WRITE_DATA: + ret = have_write; + break; + default: /* FILE_READ_DATA|FILE_WRITE_DATA */ + ret = (have_write & have_read); + break; + } + DEBUG(10,("check_posix_acl_group_access: file %s " + "match on user %u -> %s.\n", + fname, (unsigned int)*puid, + ret ? "can access" : "cannot access")); if (seen_mask) { goto done; } @@ -4002,6 +4043,7 @@ match on user %u -> %s.\n", fname, (unsigned int)*puid, ret ? "can write" : "can SMB_ACL_TAG_T tagtype; SMB_ACL_PERMSET_T permset; int have_write = -1; + int have_read = -1; /* get_next... */ if (entry_id == SMB_ACL_FIRST_ENTRY) @@ -4015,6 +4057,11 @@ match on user %u -> %s.\n", fname, (unsigned int)*puid, ret ? "can write" : "can goto check_stat; } + have_read = SMB_VFS_SYS_ACL_GET_PERM(conn, permset, SMB_ACL_READ); + if (have_read == -1) { + goto check_stat; + } + have_write = SMB_VFS_SYS_ACL_GET_PERM(conn, permset, SMB_ACL_WRITE); if (have_write == -1) { goto check_stat; @@ -4025,6 +4072,7 @@ match on user %u -> %s.\n", fname, (unsigned int)*puid, ret ? "can write" : "can * canonicalize to 0 or 1. */ have_write = (have_write ? 1 : 0); + have_read = (have_read ? 1 : 0); switch(tagtype) { case SMB_ACL_GROUP: @@ -4049,13 +4097,25 @@ match on user %u -> %s.\n", fname, (unsigned int)*puid, ret ? "can write" : "can for (cu_gid = get_current_user_gid_first(&i); cu_gid != (gid_t)-1; cu_gid = get_current_user_gid_next(&i)) { if (cu_gid == *pgid) { - ret = have_write; - DEBUG(10,("check_posix_acl_group_write: file %s \ -match on group %u -> can write.\n", fname, (unsigned int)cu_gid )); + switch (access_mask) { + case FILE_READ_DATA: + ret = have_read; + break; + case FILE_WRITE_DATA: + ret = have_write; + break; + default: /* FILE_READ_DATA|FILE_WRITE_DATA */ + ret = (have_write & have_read); + break; + } - /* If we don't have write permission this entry doesn't + DEBUG(10,("check_posix_acl_group_access: file %s " + "match on group %u -> can access.\n", + fname, (unsigned int)cu_gid )); + + /* If we don't have access permission this entry doesn't terminate the enumeration of the entries. */ - if (have_write) { + if (ret) { goto done; } /* But does terminate the group iteration. */ @@ -4072,12 +4132,12 @@ match on group %u -> can write.\n", fname, (unsigned int)cu_gid )); /* If ret is -1 here we didn't match on the user entry or supplemental group entries. */ - DEBUG(10,("check_posix_acl_group_write: ret = %d before check_stat:\n", ret)); + DEBUG(10,("check_posix_acl_group_access: ret = %d before check_stat:\n", ret)); check_stat: /* - * We only check the S_IWGRP permissions if we haven't already + * We only check the S_I[RW]GRP permissions if we haven't already * seen an owning group SMB_ACL_GROUP_OBJ ace entry. If there is an * SMB_ACL_GROUP_OBJ ace entry then the group bits in st_gid are * the same as the SMB_ACL_MASK bits, not the SMB_ACL_GROUP_OBJ @@ -4094,16 +4154,33 @@ match on group %u -> can write.\n", fname, (unsigned int)cu_gid )); for (cu_gid = get_current_user_gid_first(&i); cu_gid != (gid_t)-1; cu_gid = get_current_user_gid_next(&i)) { if (cu_gid == psbuf->st_gid) { - ret = (psbuf->st_mode & S_IWGRP) ? 1 : 0; - DEBUG(10,("check_posix_acl_group_write: file %s \ -match on owning group %u -> %s.\n", fname, (unsigned int)psbuf->st_gid, ret ? "can write" : "cannot write")); + switch (access_mask) { + case FILE_READ_DATA: + ret = (psbuf->st_mode & S_IRGRP) ? 1 : 0; + break; + case FILE_WRITE_DATA: + ret = (psbuf->st_mode & S_IWGRP) ? 1 : 0; + break; + default: /* FILE_READ_DATA|FILE_WRITE_DATA */ + if ((psbuf->st_mode & (S_IWGRP|S_IRGRP)) == (S_IWGRP|S_IRGRP)) { + ret = 1; + } else { + ret = 0; + } + break; + } + DEBUG(10,("check_posix_acl_group_access: file %s " + "match on owning group %u -> %s.\n", + fname, (unsigned int)psbuf->st_gid, + ret ? "can access" : "cannot access")); break; } } if (cu_gid == (gid_t)-1) { - DEBUG(10,("check_posix_acl_group_write: file %s \ -failed to match on user or group in token (ret = %d).\n", fname, ret )); + DEBUG(10,("check_posix_acl_group_access: file %s " + "failed to match on user or group in token (ret = %d).\n", + fname, ret )); } } @@ -4113,7 +4190,7 @@ failed to match on user or group in token (ret = %d).\n", fname, ret )); SMB_VFS_SYS_ACL_FREE_ACL(conn, posix_acl); } - DEBUG(10,("check_posix_acl_group_write: file %s returning (ret = %d).\n", fname, ret )); + DEBUG(10,("check_posix_acl_group_access: file %s returning (ret = %d).\n", fname, ret )); return ret; } @@ -4169,7 +4246,7 @@ BOOL can_delete_file_in_directory(connection_struct *conn, const char *fname) #endif /* Check group or explicit user acl entry write access. */ - ret = check_posix_acl_group_write(conn, dname, &sbuf); + ret = check_posix_acl_group_access(conn, dname, &sbuf, FILE_WRITE_DATA); if (ret == 0 || ret == 1) { return ret ? True : False; } @@ -4179,15 +4256,23 @@ BOOL can_delete_file_in_directory(connection_struct *conn, const char *fname) } /**************************************************************************** - Actually emulate the in-kernel access checking for write access. We need + Actually emulate the in-kernel access checking for read/write access. We need this to successfully check for ability to write for dos filetimes. Note this doesn't take into account share write permissions. ****************************************************************************/ -BOOL can_write_to_file(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf) +BOOL can_access_file(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf, uint32 access_mask) { int ret; + if (!(access_mask & (FILE_READ_DATA|FILE_WRITE_DATA))) { + return False; + } + access_mask &= (FILE_READ_DATA|FILE_WRITE_DATA); + + DEBUG(10,("can_access_file: requesting 0x%x on file %s\n", + (unsigned int)access_mask, fname )); + if (current_user.ut.uid == 0 || conn->admin_user) { /* I'm sorry sir, I didn't know you were root... */ return True; @@ -4200,19 +4285,56 @@ BOOL can_write_to_file(connection_struct *conn, const char *fname, SMB_STRUCT_ST } } - /* Check primary owner write access. */ + /* Check primary owner access. */ if (current_user.ut.uid == psbuf->st_uid) { - return (psbuf->st_mode & S_IWUSR) ? True : False; + switch (access_mask) { + case FILE_READ_DATA: + return (psbuf->st_mode & S_IRUSR) ? True : False; + + case FILE_WRITE_DATA: + return (psbuf->st_mode & S_IWUSR) ? True : False; + + default: /* FILE_READ_DATA|FILE_WRITE_DATA */ + + if ((psbuf->st_mode & (S_IWUSR|S_IRUSR)) == (S_IWUSR|S_IRUSR)) { + return True; + } else { + return False; + } + } } - /* Check group or explicit user acl entry write access. */ - ret = check_posix_acl_group_write(conn, fname, psbuf); + /* Check group or explicit user acl entry access. */ + ret = check_posix_acl_group_access(conn, fname, psbuf, access_mask); if (ret == 0 || ret == 1) { return ret ? True : False; } - /* Finally check other write access. */ - return (psbuf->st_mode & S_IWOTH) ? True : False; + /* Finally check other access. */ + switch (access_mask) { + case FILE_READ_DATA: + return (psbuf->st_mode & S_IROTH) ? True : False; + + case FILE_WRITE_DATA: + return (psbuf->st_mode & S_IWOTH) ? True : False; + + default: /* FILE_READ_DATA|FILE_WRITE_DATA */ + + if ((psbuf->st_mode & (S_IWOTH|S_IROTH)) == (S_IWOTH|S_IROTH)) { + return True; + } + } + return False; +} + +/**************************************************************************** + Userspace check for write access. + Note this doesn't take into account share write permissions. +****************************************************************************/ + +BOOL can_write_to_file(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf) +{ + return can_access_file(conn, fname, psbuf, FILE_WRITE_DATA); } /******************************************************************** |