Pull security subsystem updates from James Morris.
Mostly ima, selinux, smack and key handling updates.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits)
integrity: do zero padding of the key id
KEYS: output last portion of fingerprint in /proc/keys
KEYS: strip 'id:' from ca_keyid
KEYS: use swapped SKID for performing partial matching
KEYS: Restore partial ID matching functionality for asymmetric keys
X.509: If available, use the raw subjKeyId to form the key description
KEYS: handle error code encoded in pointer
selinux: normalize audit log formatting
selinux: cleanup error reporting in selinux_nlmsg_perm()
KEYS: Check hex2bin()'s return when generating an asymmetric key ID
ima: detect violations for mmaped files
ima: fix race condition on ima_rdwr_violation_check and process_measurement
ima: added ima_policy_flag variable
ima: return an error code from ima_add_boot_aggregate()
ima: provide 'ima_appraise=log' kernel option
ima: move keyring initialization to ima_init()
PKCS#7: Handle PKCS#7 messages that contain no X.509 certs
PKCS#7: Better handling of unsupported crypto
KEYS: Overhaul key identification when searching for asymmetric keys
KEYS: Implement binary asymmetric key ID handling
...
Previous version of KEYS used to output last 4 bytes of fingerprint.
Now it outputs 8 last bytes of raw subject, which does not make any
visual meaning at all. This patch restores old behavior.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
The 'id:' prefix must be stripped for asymmetric_key_hex_to_key_id() to be
able to process ca_keyid.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Earlier KEYS code used pure subject key identifiers (fingerprint)
for searching keys. Latest merged code removed that and broke
compatibility with integrity subsytem signatures and original
format of module signatures.
This patch returns back partial matching on SKID.
Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Bring back the functionality whereby an asymmetric key can be matched with a
partial match on one of its IDs.
Whilst we're at it, allow for the possibility of having an increased number of
IDs.
Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Module signing matches keys by comparing against the key description exactly.
However, the way the key description gets constructed got changed to be
composed of the subject name plus the certificate serial number instead of the
subject name and the subjectKeyId. I changed this to avoid problems with
certificates that don't *have* a subjectKeyId.
Instead, if available, use the raw subjectKeyId to form the key description
and only use the serial number if the subjectKeyId doesn't exist.
Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
As it stands, the code to generate an asymmetric key ID prechecks the hex
string it is given whilst determining the length, before it allocates the
buffer for hex2bin() to translate into - which mean that checking the result of
hex2bin() is redundant.
Unfortunately, hex2bin() is marked as __must_check, which means that the
following warning may be generated if the return value isn't checked:
crypto/asymmetric_keys/asymmetric_type.c: In function
asymmetric_key_hex_to_key_id:
crypto/asymmetric_keys/asymmetric_type.c:110: warning: ignoring return
value of hex2bin, declared with attribute warn_unused_result
The warning can't be avoided by casting the result to void.
Instead, use strlen() to check the length of the string and ignore the fact
that the string might not be entirely valid hex until after the allocation has
been done - in which case we can use the result of hex2bin() for this.
Signed-off-by: David Howells <dhowells@redhat.com>
The X.509 certificate list in a PKCS#7 message is optional. To save space, we
can omit the inclusion of any X.509 certificates if we are sure that we can
look the relevant public key up by the serial number and issuer given in a
signed info block.
This also supports use of a signed info block for which we can't find a
matching X.509 cert in the certificate list, though it be populated.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Provide better handling of unsupported crypto when verifying a PKCS#7 message.
If we can't bridge the gap between a pair of X.509 certs or between a signed
info block and an X.509 cert because it involves some crypto we don't support,
that's not necessarily the end of the world as there may be other ways points
at which we can intersect with a ring of trusted keys.
Instead, only produce ENOPKG immediately if all the signed info blocks in a
PKCS#7 message require unsupported crypto to bridge to the first X.509 cert.
Otherwise, we defer the generation of ENOPKG until we get ENOKEY during trust
validation.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Make use of the new match string preparsing to overhaul key identification
when searching for asymmetric keys. The following changes are made:
(1) Use the previously created asymmetric_key_id struct to hold the following
key IDs derived from the X.509 certificate or PKCS#7 message:
id: serial number + issuer
skid: subjKeyId + subject
authority: authKeyId + issuer
(2) Replace the hex fingerprint attached to key->type_data[1] with an
asymmetric_key_ids struct containing the id and the skid (if present).
(3) Make the asymmetric_type match data preparse select one of two searches:
(a) An iterative search for the key ID given if prefixed with "id:". The
prefix is expected to be followed by a hex string giving the ID to
search for. The criterion key ID is checked against all key IDs
recorded on the key.
(b) A direct search if the key ID is not prefixed with "id:". This will
look for an exact match on the key description.
(4) Make x509_request_asymmetric_key() take a key ID. This is then converted
into "id:<hex>" and passed into keyring_search() where match preparsing
will turn it back into a binary ID.
(5) X.509 certificate verification then takes the authority key ID and looks
up a key that matches it to find the public key for the certificate
signature.
(6) PKCS#7 certificate verification then takes the id key ID and looks up a
key that matches it to find the public key for the signed information
block signature.
Additional changes:
(1) Multiple subjKeyId and authKeyId values on an X.509 certificate cause the
cert to be rejected with -EBADMSG.
(2) The 'fingerprint' ID is gone. This was primarily intended to convey PGP
public key fingerprints. If PGP is supported in future, this should
generate a key ID that carries the fingerprint.
(3) Th ca_keyid= kernel command line option is now converted to a key ID and
used to match the authority key ID. Possibly this should only match the
actual authKeyId part and not the issuer as well.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Implement the first step in using binary key IDs for asymmetric keys rather
than hex string keys.
The previously added match data preparsing will be able to convert hex
criterion strings into binary which can then be compared more rapidly.
Further, we actually want more then one ID string per public key. The problem
is that X.509 certs refer to other X.509 certs by matching Issuer + AuthKeyId
to Subject + SubjKeyId, but PKCS#7 messages match against X.509 Issuer +
SerialNumber.
This patch just provides facilities for a later patch to make use of.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Make the key matching functions pointed to by key_match_data::cmp return bool
rather than int.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
A previous patch added a ->match_preparse() method to the key type. This is
allowed to override the function called by the iteration algorithm.
Therefore, we can just set a default that simply checks for an exact match of
the key description with the original criterion data and allow match_preparse
to override it as needed.
The key_type::match op is then redundant and can be removed, as can the
user_match() function.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Remove key_type::def_lookup_type as it's no longer used. The information now
defaults to KEYRING_SEARCH_LOOKUP_DIRECT but may be overridden by
type->match_preparse().
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Preparse the match data. This provides several advantages:
(1) The preparser can reject invalid criteria up front.
(2) The preparser can convert the criteria to binary data if necessary (the
asymmetric key type really wants to do binary comparison of the key IDs).
(3) The preparser can set the type of search to be performed. This means
that it's not then a one-off setting in the key type.
(4) The preparser can set an appropriate comparator function.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Merge in keyrings fixes, at least some of which later patches depend on:
(1) Reinstate the production of EPERM for key types beginning with '.' in
requests from userspace.
(2) Tidy up the cleanup of PKCS#7 message signed information blocks and fix a
bug this made more obvious.
Signed-off-by: David Howells <dhowells@redhat.coM>
Fix the parser cleanup code to drain parsed out X.509 certs in the case that
the decode fails and we jump to error_decode.
The function is rearranged so that the same cleanup code is used in the success
case as the error case - just that the message descriptor under construction is
only released if it is still pointed to by the context struct at that point.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
The code to free a signed info block is repeated several times, so move the
code to do it into a function of its own. This gives us a place to add clean
ups for stuff that gets added to pkcs7_signed_info.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Printing in base signature handling should have a prefix, so set pr_fmt().
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Relax the check on the length of the PKCS#7 cert as it appears that the PE
file wrapper size gets rounded up to the nearest 8.
The debugging output looks like this:
PEFILE: ==> verify_pefile_signature()
PEFILE: ==> pefile_parse_binary()
PEFILE: checksum @ 110
PEFILE: header size = 200
PEFILE: cert = 968 @547be0 [68 09 00 00 00 02 02 00 30 82 09 56 ]
PEFILE: sig wrapper = { 968, 200, 2 }
PEFILE: Signature data not PKCS#7
The wrapper is the first 8 bytes of the hex dump inside []. This indicates a
length of 0x968 bytes, including the wrapper header - so 0x960 bytes of
payload.
The ASN.1 wrapper begins [ ... 30 82 09 56 ]. That indicates an object of size
0x956 - a four byte discrepency, presumably just padding for alignment
purposes.
So we just check that the ASN.1 container is no bigger than the payload and
reduce the recorded size appropriately.
Whilst we're at it, allow shorter PKCS#7 objects that manage to squeeze within
127 or 255 bytes. It's just about conceivable if no X.509 certs are included
in the PKCS#7 message.
Reported-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Peter Jones <pjones@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
The length of the name of an asymmetric key subtype must be stored in struct
asymmetric_key_subtype::name_len so that it can be matched by a search for
"<subkey_name>:<partial_fingerprint>". Fix the public_key subtype to have
name_len set.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Need to export x509_request_asymmetric_key() so that PKCS#7 can use it if
compiled as a module.
Reported-by: James Morris <jmorris@namei.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Linus Torvalds
Dmitry Kasatkin
David Howells