TOMOYO
ForkHello.
florian.lissandres wrote:
> And I would like to have the confirmation that Tomoyo checks if a file
> exists before to read through its policy?
LSM modules do not receive queries from LSM hooks if the file to be opened
does not exist.
> Because, for exemple, with vim:
>
> Tomoyo-queryd catch: file read /usr/share/vim/vim73/lang/fr/LC_MESSAGE/vim.mo
>
> But strace catch, juste before:
> open("/usr/share/vim/vim73/lang/fr_FR/LC_MESSAGE/vim.mo",O_RDONLY) =
> -1 ENOENT (no such file or directory)
>
The pathname which is in the form of "char *" passed from user space is
converted to a "struct vfsmount"/"struct dentry" pair in the kernel.
LSM modules receive the "struct vfsmount"/"struct dentry" pair and
TOMOYO recalculates "char *" from the "struct vfsmount"/"struct dentry" pair
and checks the permission of the recalculated "char *".
If the pathname does not exist (and the pathname is not about to be created),
conversion to the "struct vfsmount"/"struct dentry" fails with ENOENT error.
Therefore,
> And so, Tomoyo has not catched the attempt of opening (catched by strace).
TOMOYO will not catch the attempt of opening (caught by strace).
Regards.