Instead of allowing public keys, with certificates signed by any
key on the system trusted keyring, to be added to a trusted keyring,
this patch further restricts the certificates to those signed by a
particular key on the system keyring.

This patch defines a new kernel parameter 'ca_keys' to identify the
specific key which must be used for trust validation of certificates.

Simplified Mimi's "KEYS: define an owner trusted keyring" patch.

Changelog:
- support for builtin x509 public keys only
- export "asymmetric_keyid_match"
- remove ifndefs MODULE
- rename kernel boot parameter from keys_ownerid to ca_keys
Signed-off-by: NDmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

Only public keys, with certificates signed by an existing
'trusted' key on the system trusted keyring, should be added
to a trusted keyring.  This patch adds support for verifying
a certificate's signature.

This is derived from David Howells pkcs7_request_asymmetric_key() patch.

Changelog v6:
- on error free key - Dmitry
- validate trust only for not already trusted keys - Dmitry
- formatting cleanup

Changelog:
- define get_system_trusted_keyring() to fix kbuild issues
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NDmitry Kasatkin <dmitry.kasatkin@gmail.com>

This reverts commit 09fbc473, which
caused the following build errors:

  crypto/asymmetric_keys/x509_public_key.c: In function ‘x509_key_preparse’:
  crypto/asymmetric_keys/x509_public_key.c:237:35: error: ‘system_trusted_keyring’ undeclared (first use in this function)
   ret = x509_validate_trust(cert, system_trusted_keyring);
                                   ^
  crypto/asymmetric_keys/x509_public_key.c:237:35: note: each undeclared identifier is reported only once for each function it appears in

reported by Jim Davis. Mimi says:

 "I made the classic mistake of requesting this patch to be upstreamed
  at the last second, rather than waiting until the next open window.

  At this point, the best course would probably be to revert the two
  commits and fix them for the next open window"
Reported-by: NJim Davis <jim.epost@gmail.com>
Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In preparation of supporting more hash algorithms with larger hash sizes
needed for signature verification, this patch replaces the 20 byte sized
digest, with a more flexible structure.  The new structure includes the
hash algorithm, digest size, and digest.

Changelog:
- recalculate filedata hash for the measurement list, if the signature
  hash digest size is greater than 20 bytes.
- use generic HASH_ALGO_
- make ima_calc_file_hash static
- scripts lindent and checkpatch fixes
Signed-off-by: NDmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

This patch makes use of the newly defined common hash algorithm info,
replacing, for example, PKEY_HASH with HASH_ALGO.

Changelog:
- Lindent fixes - Mimi

CC: David Howells <dhowells@redhat.com>
Signed-off-by: NDmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

This patch fixes lack of license, otherwise x509_key_parser.ko taints kernel.
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Only public keys, with certificates signed by an existing
'trusted' key on the system trusted keyring, should be added
to a trusted keyring.  This patch adds support for verifying
a certificate's signature.

This is derived from David Howells pkcs7_request_asymmetric_key() patch.
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Remove the certificate date checks that are performed when a certificate is
parsed.  There are two checks: a valid from and a valid to.  The first check is
causing a lot of problems with system clocks that don't keep good time and the
second places an implicit expiry date upon the kernel when used for module
signing, so do we really need them?
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: David Woodhouse <dwmw2@infradead.org>
cc: Rusty Russell <rusty@rustcorp.com.au>
cc: Josh Boyer <jwboyer@redhat.com>
cc: Alexander Holler <holler@ahsoftware.de>
cc: stable@vger.kernel.org

Handle certificates that lack an authorityKeyIdentifier field by assuming
they're self-signed and checking their signatures against themselves.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NJosh Boyer <jwboyer@redhat.com>

Check that the algorithm IDs obtained from the ASN.1 parse by OID lookup
corresponds to algorithms that are available to us.
Reported-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Embed a public_key_signature struct in struct x509_certificate, eliminating
now unnecessary fields, and split x509_check_signature() to create a filler
function for it that attaches a digest of the signed data and an MPI that
represents the signature data.  x509_free_certificate() is then modified to
deal with these.

Whilst we're at it, export both x509_check_signature() and the new
x509_get_sig_params().
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NJosh Boyer <jwboyer@redhat.com>

Modify public_key_verify_signature() so that it now takes a public_key struct
rather than a key struct and supply a wrapper that takes a key struct.  The
wrapper is then used by the asymmetric key subtype and the modified function is
used by X.509 self-signature checking and can be used by other things also.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NJosh Boyer <jwboyer@redhat.com>

Store public key algo ID in public_key struct for reference purposes.  This
allows it to be removed from the x509_certificate struct and used to find a
default in public_key_verify_signature().
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NJosh Boyer <jwboyer@redhat.com>

Move the public-key algorithm pointer array from x509_public_key.c to
public_key.c as it isn't X.509 specific.

Note that to make this configure correctly, the public key part must be
dependent on the RSA module rather than the other way round.  This needs a
further patch to make use of the crypto module loading stuff rather than using
a fixed table.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NJosh Boyer <jwboyer@redhat.com>

Rename the arrays of public key parameters (public key algorithm names, hash
algorithm names and ID type names) so that the array name ends in "_name".
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NJosh Boyer <jwboyer@redhat.com>

Some debugging printk() calls should've been converted to pr_devel() calls.
Do that now.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

The current choice of lifetime for the autogenerated X.509 of 100 years,
putting the validTo date in 2112, causes problems on 32-bit systems where a
32-bit time_t wraps in 2106.  64-bit x86_64 systems seem to be unaffected.

This can result in something like:

	Loading module verification certificates
	X.509: Cert 6e03943da0f3b015ba6ed7f5e0cac4fe48680994 has expired
	MODSIGN: Problem loading in-kernel X.509 certificate (-127)

Or:

	X.509: Cert 6e03943da0f3b015ba6ed7f5e0cac4fe48680994 is not yet valid
	MODSIGN: Problem loading in-kernel X.509 certificate (-129)

Instead of turning the dates into time_t values and comparing, turn the system
clock and the ASN.1 dates into tm structs and compare those piecemeal instead.
Reported-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NJosh Boyer <jwboyer@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Add a crypto key parser for binary (DER) encoded X.509 certificates.  The
certificate is parsed and, if possible, the signature is verified.

An X.509 key can be added like this:

	# keyctl padd crypto bar @s </tmp/x509.cert
	15768135

and displayed like this:

	# cat /proc/keys
	00f09a47 I--Q---     1 perm 39390000     0     0 asymmetri bar: X509.RSA e9fd6d08 []

Note that this only works with binary certificates.  PEM encoded certificates
are ignored by the parser.

Note also that the X.509 key ID is not congruent with the PGP key ID, but for
the moment, they will match.

If a NULL or "" name is given to add_key(), then the parser will generate a key
description from the CertificateSerialNumber and Name fields of the
TBSCertificate:

	00aefc4e I--Q---     1 perm 39390000     0     0 asymmetri bfbc0cd76d050ea4:/C=GB/L=Cambridge/O=Red Hat/CN=kernel key: X509.RSA 0c688c7b []
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>