Commit Graph

62 Commits

Author SHA1 Message Date
David Howells cf5b50fd2d X.509: Need to export x509_request_asymmetric_key()
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>
2014-08-03 12:54:48 +01:00
David Howells 412eccbadf PKCS#7: X.509 certificate issuer and subject are mandatory fields in the ASN.1
X.509 certificate issuer and subject fields are mandatory fields in the ASN.1
and so their existence needn't be tested for.  They are guaranteed to end up
with an empty string if the name material has nothing we can use (see
x509_fabricate_name()).

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-07-31 14:46:44 +01:00
David Howells 5ce43ad282 PKCS#7: Use x509_request_asymmetric_key()
pkcs7_request_asymmetric_key() and x509_request_asymmetric_key() do the same
thing, the latter being a copy of the former created by the IMA folks, so drop
the PKCS#7 version as the X.509 location is more general.

Whilst we're at it, rename the arguments of x509_request_asymmetric_key() to
better reflect what the values being passed in are intended to match on an
X.509 cert.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-29 13:07:58 +01:00
David Howells 185de09c6a X.509: x509_request_asymmetric_keys() doesn't need string length arguments
x509_request_asymmetric_keys() doesn't need the lengths of the NUL-terminated
strings passing in as it can work that out for itself.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-28 14:55:55 +01:00
Wei Yongjun 63d2551ea7 PKCS#7: fix sparse non static symbol warning
Fixes the following sparse warnings:

crypto/asymmetric_keys/pkcs7_key_type.c:73:17: warning:
 symbol 'key_type_pkcs7' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
2014-07-28 14:55:54 +01:00
David Howells 8f3438ccea PKCS#7: Missing inclusion of linux/err.h
crypto/asymmetric_keys/pkcs7_key_type.c needs to #include linux/err.h rather
than relying on getting it through other headers.

Without this, the powerpc allyesconfig build fails.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David Howells <dhowells@redhat.com>
2014-07-25 11:33:53 +01:00
David Howells 633706a2ee Merge branch 'keys-fixes' into keys-next
Signed-off-by: David Howells <dhowells@redhat.com>
2014-07-22 21:55:45 +01:00
David Howells 64724cfc6e Merge remote-tracking branch 'integrity/next-with-keys' into keys-next
Signed-off-by: David Howells <dhowells@redhat.com>
2014-07-22 21:54:43 +01:00
David Howells 6204e00255 Signed PE file verifier
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIVAwUAU71KqhOxKuMESys7AQKIwRAAgOXB0hjYkWKCHL2B1/8bNUtRKQKHsCms
 4HgNuLQ4v+RjpXDd4u0HvjkuD2ADDZlBPNSylsLsrnSXS7gH/b36vetAi8zYR/6B
 Tuvorh6BfnOkN61Xg0mwlnXkp9jisTwaZofMTDlpQ4gPAAy098Lb73ONIIlJFIH9
 WrUH/LLcPqtexdOOFtXPTBH0uz+qu8tcQHAotkP7Uwr4lDliVu1u4F2HkxRPvLjc
 IKSgb1mRa0AU0mKXbdqFREBhpVIOPS7r5mIisKnUh2d8LysSiA++zlD8/t2pfsVM
 enR7fo9pBEtJwhCrkff2p39DijR4M7s+SYF9soa9+9HQADt9D4bEtliqejGEkuQP
 CBl4LZ4eHlh1bjQbay+PixDmFxEbN14IKkvNaXBvoax8f0DdXV2URGxmhU0tM08U
 SFt2FaHhlBOsn4mhSoKJQnfHla5MP06ukrz4T+Qn2xd+lAX9e/sEBUQqT26o5Mgt
 3yTaBrg4PREYjPVhguKT04tWrMdtvxY0nKRuUUeEcT7EQNVB5v/efGaWCxLI5k3O
 wbkq5JvzSdq+VJOrby8m37fnEN7pxmF7mwOPXYfe3WPwJeX7xiYRc2ZGFntKdNzn
 zSNKC4/OYiNwn+2ANL89kcJ3pJyoJ57SsMPiXpCCekPIcLtvGddoCvZae6f171HA
 ZzlbxkjIxg0=
 =e1NL
 -----END PGP SIGNATURE-----

Merge tag 'keys-pefile-20140709' into keys-next

Here's a set of changes that implement a PE file signature checker.

This provides the following facility:

 (1) Extract the signature from the PE file.  This is a PKCS#7 message
     containing, as its data, a hash of the signed parts of the file.

 (2) Digest the signed parts of the file.

 (3) Compare the digest with the one from the PKCS#7 message.

 (4) Validate the signatures on the PKCS#7 message and indicate
     whether it was matched by a trusted key.

Signed-off-by: David Howells <dhowells@redhat.com>
2014-07-22 21:54:05 +01:00
David Howells 1ca72c96db PKCS#7 message parser
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIVAwUAU7vyohOxKuMESys7AQJRkQ//XhtkCB9qDPrD/Hq6s3SDB7FCPWk8eJ9M
 GhawiLonBFgsRqWst20cW1syc+7ECjkTZU0vD5GqMHealXj9Fho+7jyf08ShP+jM
 AFBRfjoHKklOuh4C1lhB5IglR1zAXpmLHA2mP/r58BjEpOBEwlmh8rri/9/kk6iX
 hAV79d23IaoM4ueGb4vVy61ZpsKA0YQadJK1xRjXzFPAuS3f4i6W7uKG9QmsJ56m
 DaP++rtyJPByRVb/tJqUeJAIPaXQg9JRXD8tNGJ2qCdulEbHJQhNzp2ukQEMmfhS
 RaogNO7jcfdM/4BeIoRJxNt3VcvHChSdbXP1YO4V792BdxnjsXO8GdEKXp53ijoP
 mZ6Z1JsmpFKPGvAWA0eQUMYU4vnRzAtIo4CgdsIAQYpGrxOOnv+28UWalm7NLC1l
 ++YCesD03atd/XrdSNF082Xh8TTcRKI1OBOtBDya2ZhKMy56Bj/l6rOYVBw+Au6E
 Yfressl7jCRaaT/ZHefZwKsJ5ac+MTcwAk0LlKflg+f8vdpMDnUfZxhUheM2EwWw
 RyTHHa6IWUyYIOTXQ88KF1PmNXgGWBhe90yrHO909yaNWBnvFbPdJ91DuXvKUjza
 SZ0GLS2+Vt+6TnlzxaHITE1ly5m3avZDAosIqEhGKymG6EL0mg469vpNGJNUbvIp
 5jZqJ8wSF5Q=
 =aRKT
 -----END PGP SIGNATURE-----

Merge tag 'keys-pkcs7-20140708' into keys-next

Here's a set of changes that implement a PKCS#7 message parser in the kernel.

The PKCS#7 message parsing will then be used to limit kexec to authenticated
kernels only if so configured.

The changes provide the following facilities:

 (1) Parse an ASN.1 PKCS#7 message and pick out useful bits such as the data
     content and the X.509 certificates used to sign it and all the data
     signatures.

 (2) Verify all the data signatures against the set of X.509 certificates
     available in the message.

 (3) Follow the certificate chains and verify that:

     (a) for every self-signed X.509 certificate, check that it validly signed
     	 itself, and:

     (b) for every non-self-signed certificate, if we have a 'parent'
     	 certificate, the former is validly signed by the latter.

 (4) Look for intersections between the certificate chains and the trusted
     keyring, if any intersections are found, verify that the trusted
     certificates signed the intersection point in the chain.

 (5) For testing purposes, a key type can be made available that will take a
     PKCS#7 message, check that the message is trustworthy, and if so, add its
     data content into the key.

Note that (5) has to be altered to take account of the preparsing patches
already committed to this branch.

Signed-off-by: David Howells <dhowells@redhat.com>
2014-07-22 21:53:21 +01:00
David Howells fc7c70e0b6 KEYS: struct key_preparsed_payload should have two payload pointers
struct key_preparsed_payload should have two payload pointers to correspond
with those in struct key.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-07-22 21:46:02 +01:00
David Howells 6a09d17bb6 KEYS: Provide a generic instantiation function
Provide a generic instantiation function for key types that use the preparse
hook.  This makes it easier to prereserve key quota before keyrings get locked
to retain the new key.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-07-18 18:56:34 +01:00
Jean Delvare 26c1821733 RSA: Don't select non-existent symbol
You can select MPILIB_EXTRA all you want, it doesn't exist ;-)

Surprised kconfig doesn't complain about that...

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
2014-07-17 21:01:27 +01:00
Dmitry Kasatkin 32c4741cb6 KEYS: validate certificate trust only with builtin keys
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 only by
builtin keys on the system keyring.

This patch defines a new option 'builtin' for the kernel parameter
'keys_ownerid' to allow trust validation using builtin keys.

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

Changelog v7:
- rename builtin_keys to use_builtin_keys

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:17 -04:00
Dmitry Kasatkin ffb70f61ba KEYS: validate certificate trust only with selected key
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: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:16 -04:00
Dmitry Kasatkin b3426827c8 KEYS: make partial key id matching as a dedicated function
To avoid code duplication this patch refactors asymmetric_key_match(),
making partial ID string match a separate function.

This patch also implicitly fixes a bug in the code.  asymmetric_key_match()
allows to match the key by its subtype. But subtype matching could be
undone if asymmetric_key_id(key) would return NULL. This patch first
checks for matching spec and then for its value.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:16 -04:00
Mimi Zohar 3be4beaf7c KEYS: verify a certificate is signed by a 'trusted' key
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: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
2014-07-17 09:35:15 -04:00
David Howells 98801c002f pefile: Validate PKCS#7 trust chain
Validate the PKCS#7 trust chain against the contents of the system keyring.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-07-09 14:58:47 +01:00
David Howells af316fc442 pefile: Digest the PE binary and compare to the PKCS#7 data
Digest the signed parts of the PE binary, canonicalising the section table
before we need it, and then compare the the resulting digest to the one in the
PKCS#7 signed content.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
Vivek Goyal dd7d66f21b pefile: Handle pesign using the wrong OID
The pesign utility had a bug where it was using OID_msIndividualSPKeyPurpose
instead of OID_msPeImageDataObjId - so allow both OIDs.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-07-09 14:58:37 +01:00
David Howells 4c0b4b1d1a pefile: Parse the "Microsoft individual code signing" data blob
The PKCS#7 certificate should contain a "Microsoft individual code signing"
data blob as its signed content.  This blob contains a digest of the signed
content of the PE binary and the OID of the digest algorithm used (typically
SHA256).

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
David Howells 3968280c76 pefile: Parse the presumed PKCS#7 content of the certificate blob
Parse the content of the certificate blob, presuming it to be PKCS#7 format.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
David Howells 09dacbbda9 pefile: Strip the wrapper off of the cert data block
The certificate data block in a PE binary has a wrapper around the PKCS#7
signature we actually want to get at.  Strip this off and check that we've got
something that appears to be a PKCS#7 signature.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
David Howells 26d1164be3 pefile: Parse a PE binary to find a key and a signature contained therein
Parse a PE binary to find a key and a signature contained therein.  Later
patches will check the signature and add the key if the signature checks out.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
David Howells 452069867c KEYS: X.509: Fix a spelling mistake
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-07-08 17:21:01 +01:00
David Howells 22d01afb21 PKCS#7: Provide a key type for testing PKCS#7
Provide a key type for testing the PKCS#7 parser.  It is given a non-detached
PKCS#7 message as payload:

	keyctl padd pkcs7_test a @s <stuff.pkcs7

The PKCS#7 wrapper is validated against the trusted certificates available and
then stripped off.  If successful, the key can be read, which will give the
data content of the PKCS#7 message.

A suitable message can be created by running make on the attached Makefile.
This will produce a file called stuff.pkcs7 for test loading.  The key3.x509
file should be put into the kernel source tree before it is built and
converted to DER form:

	openssl x509 -in .../pkcs7/key3.x509 -outform DER -out key3.x509

###############################################################################
#
# Create a pkcs7 message and sign it twice
#
#	openssl x509 -text -inform PEM -noout -in key2.x509
#
###############################################################################
stuff.pkcs7: stuff.txt key2.priv key2.x509 key4.priv key4.x509 certs
	$(RM) $@
	openssl smime -sign \
		-signer key2.x509 \
		-inkey key2.priv \
		-signer key4.x509 \
		-inkey key4.priv \
		-in stuff.txt \
		-certfile certs \
		-out $@ -binary -outform DER -nodetach
	openssl pkcs7 -inform DER -in stuff.pkcs7  -print_certs -noout
	openssl asn1parse -inform DER -in stuff.pkcs7  -i >out

stuff.txt:
	echo "The quick red fox jumped over the lazy brown dog" >stuff.txt

certs: key1.x509 key2.x509 key3.x509 key4.x509
	cat key{1,3}.x509 >$@

###############################################################################
#
# Generate a signed key
#
#	openssl x509 -text -inform PEM -noout -in key2.x509
#
###############################################################################
key2.x509: key2.x509_unsigned key1.priv key1.x509
	openssl x509 \
		-req -in key2.x509_unsigned \
		-out key2.x509 \
		-extfile key2.genkey -extensions myexts \
		-CA key1.x509 \
		-CAkey key1.priv \
		-CAcreateserial

key2.priv key2.x509_unsigned: key2.genkey
	openssl req -new -nodes -utf8 -sha1 -days 36500 \
		-batch -outform PEM \
		-config key2.genkey \
		-keyout key2.priv \
		-out key2.x509_unsigned

key2.genkey:
	@echo Generating X.509 key generation config
	@echo  >$@ "[ req ]"
	@echo >>$@ "default_bits = 4096"
	@echo >>$@ "distinguished_name = req_distinguished_name"
	@echo >>$@ "prompt = no"
	@echo >>$@ "string_mask = utf8only"
	@echo >>$@ "x509_extensions = myexts"
	@echo >>$@
	@echo >>$@ "[ req_distinguished_name ]"
	@echo >>$@ "O = Magrathea"
	@echo >>$@ "CN = PKCS7 key 2"
	@echo >>$@ "emailAddress = slartibartfast@magrathea.h2g2"
	@echo >>$@
	@echo >>$@ "[ myexts ]"
	@echo >>$@ "basicConstraints=critical,CA:FALSE"
	@echo >>$@ "keyUsage=digitalSignature"
	@echo >>$@ "subjectKeyIdentifier=hash"
	@echo >>$@ "authorityKeyIdentifier=keyid"

###############################################################################
#
# Generate a couple of signing keys
#
#	openssl x509 -text -inform PEM -noout -in key1.x509
#
###############################################################################
key1.x509: key1.x509_unsigned key4.priv key4.x509
	openssl x509 \
		-req -in key1.x509_unsigned \
		-out key1.x509 \
		-extfile key1.genkey -extensions myexts \
		-CA key4.x509 \
		-CAkey key4.priv \
		-CAcreateserial

key1.priv key1.x509_unsigned: key1.genkey
	openssl req -new -nodes -utf8 -sha1 -days 36500 \
		-batch -outform PEM \
		-config key1.genkey \
		-keyout key1.priv \
		-out key1.x509_unsigned

key1.genkey:
	@echo Generating X.509 key generation config
	@echo  >$@ "[ req ]"
	@echo >>$@ "default_bits = 4096"
	@echo >>$@ "distinguished_name = req_distinguished_name"
	@echo >>$@ "prompt = no"
	@echo >>$@ "string_mask = utf8only"
	@echo >>$@ "x509_extensions = myexts"
	@echo >>$@
	@echo >>$@ "[ req_distinguished_name ]"
	@echo >>$@ "O = Magrathea"
	@echo >>$@ "CN = PKCS7 key 1"
	@echo >>$@ "emailAddress = slartibartfast@magrathea.h2g2"
	@echo >>$@
	@echo >>$@ "[ myexts ]"
	@echo >>$@ "basicConstraints=critical,CA:TRUE"
	@echo >>$@ "keyUsage=digitalSignature,keyCertSign"
	@echo >>$@ "subjectKeyIdentifier=hash"
	@echo >>$@ "authorityKeyIdentifier=keyid"

###############################################################################
#
# Generate a signed key
#
#	openssl x509 -text -inform PEM -noout -in key4.x509
#
###############################################################################
key4.x509: key4.x509_unsigned key3.priv key3.x509
	openssl x509 \
		-req -in key4.x509_unsigned \
		-out key4.x509 \
		-extfile key4.genkey -extensions myexts \
		-CA key3.x509 \
		-CAkey key3.priv \
		-CAcreateserial

key4.priv key4.x509_unsigned: key4.genkey
	openssl req -new -nodes -utf8 -sha1 -days 36500 \
		-batch -outform PEM \
		-config key4.genkey \
		-keyout key4.priv \
		-out key4.x509_unsigned

key4.genkey:
	@echo Generating X.509 key generation config
	@echo  >$@ "[ req ]"
	@echo >>$@ "default_bits = 4096"
	@echo >>$@ "distinguished_name = req_distinguished_name"
	@echo >>$@ "prompt = no"
	@echo >>$@ "string_mask = utf8only"
	@echo >>$@ "x509_extensions = myexts"
	@echo >>$@
	@echo >>$@ "[ req_distinguished_name ]"
	@echo >>$@ "O = Magrathea"
	@echo >>$@ "CN = PKCS7 key 4"
	@echo >>$@ "emailAddress = slartibartfast@magrathea.h2g2"
	@echo >>$@
	@echo >>$@ "[ myexts ]"
	@echo >>$@ "basicConstraints=critical,CA:TRUE"
	@echo >>$@ "keyUsage=digitalSignature,keyCertSign"
	@echo >>$@ "subjectKeyIdentifier=hash"
	@echo >>$@ "authorityKeyIdentifier=keyid"

###############################################################################
#
# Generate a couple of signing keys
#
#	openssl x509 -text -inform PEM -noout -in key3.x509
#
###############################################################################
key3.priv key3.x509: key3.genkey
	openssl req -new -nodes -utf8 -sha1 -days 36500 \
		-batch -x509 -outform PEM \
		-config key3.genkey \
		-keyout key3.priv \
		-out key3.x509

key3.genkey:
	@echo Generating X.509 key generation config
	@echo  >$@ "[ req ]"
	@echo >>$@ "default_bits = 4096"
	@echo >>$@ "distinguished_name = req_distinguished_name"
	@echo >>$@ "prompt = no"
	@echo >>$@ "string_mask = utf8only"
	@echo >>$@ "x509_extensions = myexts"
	@echo >>$@
	@echo >>$@ "[ req_distinguished_name ]"
	@echo >>$@ "O = Magrathea"
	@echo >>$@ "CN = PKCS7 key 3"
	@echo >>$@ "emailAddress = slartibartfast@magrathea.h2g2"
	@echo >>$@
	@echo >>$@ "[ myexts ]"
	@echo >>$@ "basicConstraints=critical,CA:TRUE"
	@echo >>$@ "keyUsage=digitalSignature,keyCertSign"
	@echo >>$@ "subjectKeyIdentifier=hash"
	@echo >>$@ "authorityKeyIdentifier=keyid"

clean:
	$(RM) *~
	$(RM) key1.* key2.* key3.* key4.* stuff.* out certs

Signed-off-by: David Howells <dhowells@redhat.com>
2014-07-08 13:50:20 +01:00
David Howells 08815b62d7 PKCS#7: Find intersection between PKCS#7 message and known, trusted keys
Find the intersection between the X.509 certificate chain contained in a PKCS#7
message and a set of keys that we already know and trust.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-08 13:50:15 +01:00
David Howells 8c76d79393 PKCS#7: Verify internal certificate chain
Verify certificate chain in the X.509 certificates contained within the PKCS#7
message as far as possible.  If any signature that we should be able to verify
fails, we reject the whole lot.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-08 13:50:11 +01:00
David Howells a4730357ee PKCS#7: Find the right key in the PKCS#7 key list and verify the signature
Find the appropriate key in the PKCS#7 key list and verify the signature with
it.  There may be several keys in there forming a chain.  Any link in that
chain or the root of that chain may be in our keyrings.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-08 13:50:08 +01:00
David Howells 9f0d33146e PKCS#7: Digest the data in a signed-data message
Digest the data in a PKCS#7 signed-data message and attach to the
public_key_signature struct contained in the pkcs7_message struct.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-08 13:50:03 +01:00
David Howells 2e3fadbf73 PKCS#7: Implement a parser [RFC 2315]
Implement a parser for a PKCS#7 signed-data message as described in part of
RFC 2315.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-08 13:49:56 +01:00
David Howells ace0107a39 X.509: Export certificate parse and free functions
Export certificate parse and free functions for use by modules.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2014-07-02 22:07:50 +01:00
David Howells 84aabd46bf X.509: Add bits needed for PKCS#7
PKCS#7 validation requires access to the serial number and the raw names in an
X.509 certificate.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2014-07-01 16:40:19 +01:00
Linus Torvalds 4c1cc40a2d Revert "KEYS: verify a certificate is signed by a 'trusted' key"
This reverts commit 09fbc47373, 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: Jim Davis <jim.epost@gmail.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-23 16:38:17 -08:00
Linus Torvalds 26b265cd29 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 - Made x86 ablk_helper generic for ARM
 - Phase out chainiv in favour of eseqiv (affects IPsec)
 - Fixed aes-cbc IV corruption on s390
 - Added constant-time crypto_memneq which replaces memcmp
 - Fixed aes-ctr in omap-aes
 - Added OMAP3 ROM RNG support
 - Add PRNG support for MSM SoC's
 - Add and use Job Ring API in caam
 - Misc fixes

[ NOTE! This pull request was sent within the merge window, but Herbert
  has some questionable email sending setup that makes him public enemy
  #1 as far as gmail is concerned.  So most of his emails seem to be
  trapped by gmail as spam, resulting in me not seeing them.  - Linus ]

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (49 commits)
  crypto: s390 - Fix aes-cbc IV corruption
  crypto: omap-aes - Fix CTR mode counter length
  crypto: omap-sham - Add missing modalias
  padata: make the sequence counter an atomic_t
  crypto: caam - Modify the interface layers to use JR API's
  crypto: caam - Add API's to allocate/free Job Rings
  crypto: caam - Add Platform driver for Job Ring
  hwrng: msm - Add PRNG support for MSM SoC's
  ARM: DT: msm: Add Qualcomm's PRNG driver binding document
  crypto: skcipher - Use eseqiv even on UP machines
  crypto: talitos - Simplify key parsing
  crypto: picoxcell - Simplify and harden key parsing
  crypto: ixp4xx - Simplify and harden key parsing
  crypto: authencesn - Simplify key parsing
  crypto: authenc - Export key parsing helper function
  crypto: mv_cesa: remove deprecated IRQF_DISABLED
  hwrng: OMAP3 ROM Random Number Generator support
  crypto: sha256_ssse3 - also test for BMI2
  crypto: mv_cesa - Remove redundant of_match_ptr
  crypto: sahara - Remove redundant of_match_ptr
  ...
2013-11-23 16:18:25 -08:00
David Howells dbed714163 KEYS: The RSA public key algorithm needs to select MPILIB
The RSA public key algorithm needs to select MPILIB directly in Kconfig as the
'select' directive is not recursive and is thus MPILIB is not enabled by
selecting MPILIB_EXTRA.

Without this, the following errors can occur:

	crypto/built-in.o: In function `RSA_verify_signature':
	rsa.c:(.text+0x1d347): undefined reference to `mpi_get_nbits'
	rsa.c:(.text+0x1d354): undefined reference to `mpi_get_nbits'
	rsa.c:(.text+0x1d36e): undefined reference to `mpi_cmp_ui'
	rsa.c:(.text+0x1d382): undefined reference to `mpi_cmp'
	rsa.c:(.text+0x1d391): undefined reference to `mpi_alloc'
	rsa.c:(.text+0x1d3b0): undefined reference to `mpi_powm'
	rsa.c:(.text+0x1d3c3): undefined reference to `mpi_free'
	rsa.c:(.text+0x1d3d8): undefined reference to `mpi_get_buffer'
	rsa.c:(.text+0x1d4d4): undefined reference to `mpi_free'
	rsa.c:(.text+0x1d503): undefined reference to `mpi_get_nbits'

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
2013-11-01 15:24:51 +00:00
Dmitry Kasatkin c7c8bb237f ima: provide support for arbitrary hash algorithms
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: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-10-25 17:16:58 -04:00
Dmitry Kasatkin 3fe78ca2fb keys: change asymmetric keys to use common hash definitions
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: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-10-25 17:15:18 -04:00
James Yonan 6bf37e5aa9 crypto: crypto_memneq - add equality testing of memory regions w/o timing leaks
When comparing MAC hashes, AEAD authentication tags, or other hash
values in the context of authentication or integrity checking, it
is important not to leak timing information to a potential attacker,
i.e. when communication happens over a network.

Bytewise memory comparisons (such as memcmp) are usually optimized so
that they return a nonzero value as soon as a mismatch is found. E.g,
on x86_64/i5 for 512 bytes this can be ~50 cyc for a full mismatch
and up to ~850 cyc for a full match (cold). This early-return behavior
can leak timing information as a side channel, allowing an attacker to
iteratively guess the correct result.

This patch adds a new method crypto_memneq ("memory not equal to each
other") to the crypto API that compares memory areas of the same length
in roughly "constant time" (cache misses could change the timing, but
since they don't reveal information about the content of the strings
being compared, they are effectively benign). Iow, best and worst case
behaviour take the same amount of time to complete (in contrast to
memcmp).

Note that crypto_memneq (unlike memcmp) can only be used to test for
equality or inequality, NOT for lexicographical order. This, however,
is not an issue for its use-cases within the crypto API.

We tried to locate all of the places in the crypto API where memcmp was
being used for authentication or integrity checking, and convert them
over to crypto_memneq.

crypto_memneq is declared noinline, placed in its own source file,
and compiled with optimizations that might increase code size disabled
("Os") because a smart compiler (or LTO) might notice that the return
value is always compared against zero/nonzero, and might then
reintroduce the same early-return optimization that we are trying to
avoid.

Using #pragma or __attribute__ optimization annotations of the code
for disabling optimization was avoided as it seems to be considered
broken or unmaintained for long time in GCC [1]. Therefore, we work
around that by specifying the compile flag for memneq.o directly in
the Makefile. We found that this seems to be most appropriate.

As we use ("Os"), this patch also provides a loop-free "fast-path" for
frequently used 16 byte digests. Similarly to kernel library string
functions, leave an option for future even further optimized architecture
specific assembler implementations.

This was a joint work of James Yonan and Daniel Borkmann. Also thanks
for feedback from Florian Weimer on this and earlier proposals [2].

  [1] http://gcc.gnu.org/ml/gcc/2012-07/msg00211.html
  [2] https://lkml.org/lkml/2013/2/10/131

Signed-off-by: James Yonan <james@openvpn.net>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-10-07 14:17:06 +08:00
Konstantin Khlebnikov e19aaa7d43 X.509: add module description and license
This patch fixes lack of license, otherwise x509_key_parser.ko taints kernel.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
Mimi Zohar 09fbc47373 KEYS: verify a certificate is signed by a 'trusted' key
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: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
David Howells cd0421dcd0 KEYS: Set the asymmetric-key type default search method
The keyring expansion patches introduces a new search method by which
key_search() attempts to walk directly to the key that has exactly the same
description as the requested one.

However, this causes inexact matching of asymmetric keys to fail.  The
solution to this is to select iterative rather than direct search as the
default search type for asymmetric keys.

As an example, the kernel might have a key like this:

	Magrathea: Glacier signing key: 6a2a0f82bad7e396665f465e4e3e1f9bd24b1226

and:

	keyctl search <keyring-ID> asymmetric id:d24b1226

should find the key, despite that not being its exact description.

Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
David Howells 124df92609 X.509: Remove certificate date checks
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: David 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
2013-09-25 17:17:01 +01:00
David Howells 17334cabc8 X.509: Handle certificates that lack an authorityKeyIdentifier field
Handle certificates that lack an authorityKeyIdentifier field by assuming
they're self-signed and checking their signatures against themselves.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:01 +01:00
David Howells 2ecdb23b8c X.509: Check the algorithm IDs obtained from parsing an X.509 certificate
Check that the algorithm IDs obtained from the ASN.1 parse by OID lookup
corresponds to algorithms that are available to us.

Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
David Howells b426beb6ee X.509: Embed public_key_signature struct and create filler function
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: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:00 +01:00
David Howells 57be4a784b X.509: struct x509_certificate needs struct tm declaring
struct x509_certificate needs struct tm declaring by #inclusion of linux/time.h
prior to its definition.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:00 +01:00
David Howells 3d167d68e3 KEYS: Split public_key_verify_signature() and make available
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: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:00 +01:00
David Howells 67f7d60b3a KEYS: Store public key algo ID in public_key struct
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: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:00 +01:00
David Howells 206ce59a10 KEYS: Move the algorithm pointer array from x509 to public_key.c
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: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 15:51:07 +01:00