46 Commits
Author SHA1 Message Date
David Howells f3eccecd78 pkcs7: Allow the signing algo to do whatever digestion it wants itself
Allow the data to be verified in a PKCS#7 or CMS message to be passed
directly to an asymmetric cipher algorithm (e.g. ML-DSA) if it wants to do
whatever passes for hashing/digestion itself.  The normal digestion of the
data is then skipped as that would be ignored unless another signed info in
the message has some other algorithm that needs it.

The 'data to be verified' may be the content of the PKCS#7 message or it
will be the authenticatedAttributes (signedAttrs if CMS), modified, if
those are present.

This is done by:

 (1) Make ->m and ->m_size point to the data to be verified rather than
     making public_key_verify_signature() access the data directly.  This
     is so that keyctl(KEYCTL_PKEY_VERIFY) will still work.

 (2) Add a flag, ->algo_takes_data, to indicate that the verification
     algorithm wants to access the data to be verified directly rather than
     having it digested first.

 (3) If the PKCS#7 message has authenticatedAttributes (or CMS
     signedAttrs), then the digest contained therein will be validated as
     now, and the modified attrs blob will either be digested or assigned
     to ->m as appropriate.

 (4) If present, always copy and modify the authenticatedAttributes (or
     signedAttrs) then digest that in one go rather than calling the shash
     update twice (once for the tag and once for the rest).

 (5) For ML-DSA, point ->m to the TBSCertificate instead of digesting it
     and using the digest.

Note that whilst ML-DSA does allow for an "external mu", CMS doesn't yet
have that standardised.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Lukas Wunner <lukas@wunner.de>
cc: Ignat Korchagin <ignat@cloudflare.com>
cc: Stephan Mueller <smueller@chronox.de>
cc: Eric Biggers <ebiggers@kernel.org>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: keyrings@vger.kernel.org
cc: linux-crypto@vger.kernel.org
2026-01-30 11:33:19 +00:00
David Howells f728074f1f pkcs7, x509: Rename ->digest to ->m
Rename ->digest and ->digest_len to ->m and ->m_size to represent the input
to the signature verification algorithm, reflecting that ->digest may no
longer actually *be* a digest.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
cc: Lukas Wunner <lukas@wunner.de>
cc: Ignat Korchagin <ignat@cloudflare.com>
cc: Stephan Mueller <smueller@chronox.de>
cc: Eric Biggers <ebiggers@kernel.org>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: keyrings@vger.kernel.org
cc: linux-crypto@vger.kernel.org
2026-01-30 11:33:08 +00:00
Dr. David Alan GilbertandHerbert Xu acb0ed8432 crypto: asymmetric_keys - Remove unused functions
encrypt_blob(), decrypt_blob() and create_signature() were some of the
functions added in 2018 by
commit 5a30771832 ("KEYS: Provide missing asymmetric key subops for new
key type ops [ver #2]")
however, they've not been used.

Remove them.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2024-11-02 18:23:24 +08:00
Clay ChangandHerbert Xu 4bb439e856 KEYS: include header for EINVAL definition
This patch includes linux/errno.h to address the issue of 'EINVAL' being
undeclared.

Signed-off-by: Clay Chang <clayc@hpe.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2024-01-26 16:39:32 +08:00
Eric SnowbergandJarkko Sakkinen 4cfb908054 KEYS: DigitalSignature link restriction
Add a new link restriction.  Restrict the addition of keys in a keyring
based on the key having digitalSignature usage set. Additionally, verify
the new certificate against the ones in the system keyrings.  Add two
additional functions to use the new restriction within either the builtin
or secondary keyrings.

[jarkko@kernel.org: Fix checkpatch.pl --strict issues]
Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-08-17 20:12:20 +00:00
Herbert Xu e5221fa6a3 KEYS: asymmetric: Move sm2 code into x509_public_key
The sm2 certificate requires a modified digest.  Move the code
for the hashing from the signature verification path into the
code where we generate the digest.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-06-23 16:15:37 +08:00
Eric SnowbergandJarkko Sakkinen 76adb2fbc6 KEYS: CA link restriction
Add a new link restriction.  Restrict the addition of keys in a keyring
based on the key to be added being a CA.

Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24 16:15:53 +03:00
Eric SnowbergandJarkko Sakkinen 567671281a KEYS: X.509: Parse Key Usage
Parse the X.509 Key Usage.  The key usage extension defines the purpose of
the key contained in the certificate.

   id-ce-keyUsage OBJECT IDENTIFIER ::=  { id-ce 15 }

      KeyUsage ::= BIT STRING {
           digitalSignature        (0),
           contentCommitment       (1),
           keyEncipherment         (2),
           dataEncipherment        (3),
           keyAgreement            (4),
           keyCertSign             (5),
           cRLSign                 (6),
           encipherOnly            (7),
           decipherOnly            (8) }

If the keyCertSign or digitalSignature is set, store it in the
public_key structure. Having the purpose of the key being stored
during parsing, allows enforcement on the usage field in the future.
This will be used in a follow on patch that requires knowing the
certificate key usage type.

Link: https://www.rfc-editor.org/rfc/rfc5280#section-4.2.1.3
Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24 16:15:53 +03:00
Eric SnowbergandJarkko Sakkinen 30eae2b037 KEYS: X.509: Parse Basic Constraints for CA
Parse the X.509 Basic Constraints.  The basic constraints extension
identifies whether the subject of the certificate is a CA.

BasicConstraints ::= SEQUENCE {
        cA                      BOOLEAN DEFAULT FALSE,
        pathLenConstraint       INTEGER (0..MAX) OPTIONAL }

If the CA is true, store it in the public_key.  This will be used
in a follow on patch that requires knowing if the public key is a CA.

Link: https://www.rfc-editor.org/rfc/rfc5280#section-4.2.1.9
Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24 16:15:53 +03:00
Eric SnowbergandJarkko Sakkinen 7f8da9915f KEYS: Create static version of public_key_verify_signature
The kernel test robot reports undefined reference to
public_key_verify_signature when CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE is
not defined. Create a static version in this case and return -EINVAL.

Fixes: db6c43bd21 ("crypto: KEYS: convert public key and digsig asym to the akcipher api")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24 16:15:52 +03:00
Andrew ZaborowskiandJarkko Sakkinen 7d30198ee2 keys: X.509 public key issuer lookup without AKID
There are non-root X.509 v3 certificates in use out there that contain
no Authority Key Identifier extension (RFC5280 section 4.2.1.1).  For
trust verification purposes the kernel asymmetric key type keeps two
struct asymmetric_key_id instances that the key can be looked up by,
and another two to look up the key's issuer.  The x509 public key type
and the PKCS7 type generate them from the SKID and AKID extensions in
the certificate.  In effect current code has no way to look up the
issuer certificate for verification without the AKID.

To remedy this, add a third asymmetric_key_id blob to the arrays in
both asymmetric_key_id's (for certficate subject) and in the
public_keys_signature's auth_ids (for issuer lookup), using just raw
subject and issuer DNs from the certificate.  Adapt
asymmetric_key_ids() and its callers to use the third ID for lookups
when none of the other two are available.  Attempt to keep the logic
intact when they are, to minimise behaviour changes.  Adapt the
restrict functions' NULL-checks to include that ID too.  Do not modify
the lookup logic in pkcs7_verify.c, the AKID extensions are still
required there.

Internally use a new "dn:" prefix to the search specifier string
generated for the key lookup in find_asymmetric_key().  This tells
asymmetric_key_match_preparse to only match the data against the raw
DN in the third ID and shouldn't conflict with search specifiers
already in use.

In effect implement what (2) in the struct asymmetric_key_id comment
(include/keys/asymmetric-type.h) is probably talking about already, so
do not modify that comment.  It is also how "openssl verify" looks up
issuer certificates without the AKID available.  Lookups by the raw
DN are unambiguous only provided that the CAs respect the condition in
RFC5280 4.2.1.1 that the AKID may only be omitted if the CA uses
a single signing key.

The following is an example of two things that this change enables.
A self-signed ceritficate is generated following the example from
https://letsencrypt.org/docs/certificates-for-localhost/, and can be
looked up by an identifier and verified against itself by linking to a
restricted keyring -- both things not possible before due to the missing
AKID extension:

$ openssl req -x509 -out localhost.crt -outform DER -keyout localhost.key \
  -newkey rsa:2048 -nodes -sha256 \
  -subj '/CN=localhost' -extensions EXT -config <( \
   echo -e "[dn]\nCN=localhost\n[req]\ndistinguished_name = dn\n[EXT]\n" \
          "subjectAltName=DNS:localhost\nkeyUsage=digitalSignature\n" \
	  "extendedKeyUsage=serverAuth")
$ keyring=`keyctl newring test @u`
$ trusted=`keyctl padd asymmetric trusted $keyring < localhost.crt`; \
  echo $trusted
39726322
$ keyctl search $keyring asymmetric dn:3112301006035504030c096c6f63616c686f7374
39726322
$ keyctl restrict_keyring $keyring asymmetric key_or_keyring:$trusted
$ keyctl padd asymmetric verified $keyring < localhost.crt

Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-01-09 00:18:42 +02:00
zhenwei piandJarkko Sakkinen f985911b7b crypto: public_key: fix overflow during implicit conversion
Hit kernel warning like this, it can be reproduced by verifying 256
bytes datafile by keyctl command, run script:
RAWDATA=rawdata
SIGDATA=sigdata

modprobe pkcs8_key_parser

rm -rf *.der *.pem *.pfx
rm -rf $RAWDATA
dd if=/dev/random of=$RAWDATA bs=256 count=1

openssl req -nodes -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem \
  -subj "/C=CN/ST=GD/L=SZ/O=vihoo/OU=dev/CN=xx.com/emailAddress=yy@xx.com"

KEY_ID=`openssl pkcs8 -in key.pem -topk8 -nocrypt -outform DER | keyctl \
  padd asymmetric 123 @s`

keyctl pkey_sign $KEY_ID 0 $RAWDATA enc=pkcs1 hash=sha1 > $SIGDATA
keyctl pkey_verify $KEY_ID 0 $RAWDATA $SIGDATA enc=pkcs1 hash=sha1

Then the kernel reports:
 WARNING: CPU: 5 PID: 344556 at crypto/rsa-pkcs1pad.c:540
   pkcs1pad_verify+0x160/0x190
 ...
 Call Trace:
  public_key_verify_signature+0x282/0x380
  ? software_key_query+0x12d/0x180
  ? keyctl_pkey_params_get+0xd6/0x130
  asymmetric_key_verify_signature+0x66/0x80
  keyctl_pkey_verify+0xa5/0x100
  do_syscall_64+0x35/0xb0
  entry_SYSCALL_64_after_hwframe+0x44/0xae

The reason of this issue, in function 'asymmetric_key_verify_signature':
'.digest_size(u8) = params->in_len(u32)' leads overflow of an u8 value,
so use u32 instead of u8 for digest_size field. And reorder struct
public_key_signature, it saves 8 bytes on a 64-bit machine.

Cc: stable@vger.kernel.org
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2021-08-23 20:25:24 +03:00
Tianjia ZhangandDavid Howells 09315b2d0d crypto: public_key: Remove redundant header file from public_key.h
The akcipher.h header file was originally introduced in SM2, and
then the definition of SM2 was moved to the existing code. This
header file is left and should be removed.

Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Ben Boeckel <mathstuf@gmail.com>
2021-01-21 16:16:10 +00:00
Herbert Xu 3093e7c16e X.509: Fix modular build of public_key_sm2
The sm2 code was split out of public_key.c in a way that breaks
modular builds.  This patch moves the code back into the same file
as the original motivation was to minimise ifdefs and that has
nothing to do with splitting the code out.

Fixes: 2155256396 ("X.509: support OSCCA SM2-with-SM3...")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-10-08 16:39:14 +11:00
Tianjia ZhangandHerbert Xu 2155256396 X.509: support OSCCA SM2-with-SM3 certificate verification
The digital certificate format based on SM2 crypto algorithm as
specified in GM/T 0015-2012. It was published by State Encryption
Management Bureau, China.

The method of generating Other User Information is defined as
ZA=H256(ENTLA || IDA || a || b || xG || yG || xA || yA), it also
specified in https://tools.ietf.org/html/draft-shen-sm2-ecdsa-02.

The x509 certificate supports SM2-with-SM3 type certificate
verification.  Because certificate verification requires ZA
in addition to tbs data, ZA also depends on elliptic curve
parameters and public key data, so you need to access tbs in sig
and calculate ZA. Finally calculate the digest of the
signature and complete the verification work. The calculation
process of ZA is declared in specifications GM/T 0009-2012
and GM/T 0003.2-2012.

Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Tested-by: Xufeng Zhang <yunbo.xufeng@linux.alibaba.com>
Reviewed-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-09-25 17:48:55 +10:00
Mauro Carvalho ChehabandJonathan Corbet 0efaaa8658 docs: crypto: convert asymmetric-keys.txt to ReST
This file is almost compatible with ReST. Just minor changes
were needed:

- Adjust document and titles markups;
- Adjust numbered list markups;
- Add a comments markup for the Contents section;
- Add markups for literal blocks.

Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/c2275ea94e0507a01b020ab66dfa824d8b1c2545.1592203650.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-19 14:03:46 -06:00
Thomas GleixnerandGreg Kroah-Hartman b4d0d230cc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public licence as published by
  the free software foundation either version 2 of the licence or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 114 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:11 +02:00
Vitaly ChikunovandHerbert Xu f1774cb895 X.509: parse public key parameters from x509 for akcipher
Some public key algorithms (like EC-DSA) keep in parameters field
important data such as digest and curve OIDs (possibly more for
different EC-DSA variants). Thus, just setting a public key (as
for RSA) is not enough.

Append parameters into the key stream for akcipher_set_{pub,priv}_key.
Appended data is: (u32) algo OID, (u32) parameters length, parameters
data.

This does not affect current akcipher API nor RSA ciphers (they could
ignore it). Idea of appending parameters to the key stream is by Herbert
Xu.

Cc: David Howells <dhowells@redhat.com>
Cc: Denis Kenzior <denkenz@gmail.com>
Cc: keyrings@vger.kernel.org
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Reviewed-by: Denis Kenzior <denkenz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-18 22:15:02 +08:00
David HowellsandJames Morris f7c4e06e06 KEYS: Allow the public_key struct to hold a private key [ver #2]
Put a flag in the public_key struct to indicate if the structure is holding
a private key.  The private key must be held ASN.1 encoded in the format
specified in RFC 3447 A.1.2.  This is the form required by crypto/rsa.c.

The software encryption subtype's verification and query functions then
need to select the appropriate crypto function to set the key.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Denis Kenzior <denkenz@gmail.com>
Tested-by: Denis Kenzior <denkenz@gmail.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-26 09:30:46 +01:00
David HowellsandJames Morris 5a30771832 KEYS: Provide missing asymmetric key subops for new key type ops [ver #2]
Provide the missing asymmetric key subops for new key type ops.  This
include query, encrypt, decrypt and create signature.  Verify signature
already exists.  Also provided are accessor functions for this:

	int query_asymmetric_key(const struct key *key,
				 struct kernel_pkey_query *info);

	int encrypt_blob(struct kernel_pkey_params *params,
			 const void *data, void *enc);
	int decrypt_blob(struct kernel_pkey_params *params,
			 const void *enc, void *data);
	int create_signature(struct kernel_pkey_params *params,
			     const void *data, void *enc);

The public_key_signature struct gains an encoding field to carry the
encoding for verify_signature().

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Denis Kenzior <denkenz@gmail.com>
Tested-by: Denis Kenzior <denkenz@gmail.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-26 09:30:46 +01:00
Mat Martineau 8e323a02e8 KEYS: Keyring asymmetric key restrict method with chaining
Add a restrict_link_by_key_or_keyring_chain link restriction that
searches for signing keys in the destination keyring in addition to the
signing key or keyring designated when the destination keyring was
created. Userspace enables this behavior by including the "chain" option
in the keyring restriction:

  keyctl(KEYCTL_RESTRICT_KEYRING, keyring, "asymmetric",
         "key_or_keyring:<signing key>:chain");

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-04 14:10:13 -07:00
Mat Martineau 7e3c4d2208 KEYS: Restrict asymmetric key linkage using a specific keychain
Adds restrict_link_by_signature_keyring(), which uses the restrict_key
member of the provided destination_keyring data structure as the
key or keyring to search for signing keys.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-04 14:10:13 -07:00
Mat Martineau aaf66c8838 KEYS: Split role of the keyring pointer for keyring restrict functions
The first argument to the restrict_link_func_t functions was a keyring
pointer. These functions are called by the key subsystem with this
argument set to the destination keyring, but restrict_link_by_signature
expects a pointer to the relevant trusted keyring.

Restrict functions may need something other than a single struct key
pointer to allow or reject key linkage, so the data used to make that
decision (such as the trust keyring) is moved to a new, fourth
argument. The first argument is now always the destination keyring.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-03 10:24:56 -07:00
David Howells a511e1af8b KEYS: Move the point of trust determination to __key_link()
Move the point at which a key is determined to be trustworthy to
__key_link() so that we use the contents of the keyring being linked in to
to determine whether the key being linked in is trusted or not.

What is 'trusted' then becomes a matter of what's in the keyring.

Currently, the test is done when the key is parsed, but given that at that
point we can only sensibly refer to the contents of the system trusted
keyring, we can only use that as the basis for working out the
trustworthiness of a new key.

With this change, a trusted keyring is a set of keys that once the
trusted-only flag is set cannot be added to except by verification through
one of the contained keys.

Further, adding a key into a trusted keyring, whilst it might grant
trustworthiness in the context of that keyring, does not automatically
grant trustworthiness in the context of a second keyring to which it could
be secondarily linked.

To accomplish this, the authentication data associated with the key source
must now be retained.  For an X.509 cert, this means the contents of the
AuthorityKeyIdentifier and the signature data.


If system keyrings are disabled then restrict_link_by_builtin_trusted()
resolves to restrict_link_reject().  The integrity digital signature code
still works correctly with this as it was previously using
KEY_FLAG_TRUSTED_ONLY, which doesn't permit anything to be added if there
is no system keyring against which trust can be determined.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-11 22:43:43 +01:00
David Howells 983023f28b KEYS: Move x509_request_asymmetric_key() to asymmetric_type.c
Move x509_request_asymmetric_key() to asymmetric_type.c so that it can be
generalised.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-11 22:41:28 +01:00