If we can't parse the PKCS7 in the appended modsig, we will free the modsig
structure and then access one of its members to determine the error value.
Fixes: 39b0709636 ("ima: Implement support for module-style appended signatures")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Define new "d-modsig" template field which holds the digest that is
expected to match the one contained in the modsig, and also new "modsig"
template field which holds the appended file signature.
Add a new "ima-modsig" defined template descriptor with the new fields as
well as the ones from the "ima-sig" descriptor.
Change ima_store_measurement() to accept a struct modsig * argument so that
it can be passed along to the templates via struct ima_event_data.
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Obtain the modsig and calculate its corresponding hash in
ima_collect_measurement().
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Implement the appraise_type=imasig|modsig option, allowing IMA to read and
verify modsig signatures.
In case a file has both an xattr signature and an appended modsig, IMA will
only use the appended signature if the key used by the xattr signature
isn't present in the IMA or platform keyring.
Because modsig verification needs to convert from an integrity keyring id
to the keyring itself, add an integrity_keyring_from_id() function in
digsig.c so that integrity_modsig_verify() can use it.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Introduce the modsig keyword to the IMA policy syntax to specify that
a given hook should expect the file to have the IMA signature appended
to it. Here is how it can be used in a rule:
appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig
With this rule, IMA will accept either a signature stored in the extended
attribute or an appended signature.
For now, the rule above will behave exactly the same as if
appraise_type=imasig was specified. The actual modsig implementation
will be introduced separately.
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
