Pull security layer updates from James Morris:
"There are a bunch of fixes to the TPM, IMA, and Keys code, with minor
fixes scattered across the subsystem.
IMA now requires signed policy, and that policy is also now measured
and appraised"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (67 commits)
X.509: Make algo identifiers text instead of enum
akcipher: Move the RSA DER encoding check to the crypto layer
crypto: Add hash param to pkcs1pad
sign-file: fix build with CMS support disabled
MAINTAINERS: update tpmdd urls
MODSIGN: linux/string.h should be #included to get memcpy()
certs: Fix misaligned data in extra certificate list
X.509: Handle midnight alternative notation in GeneralizedTime
X.509: Support leap seconds
Handle ISO 8601 leap seconds and encodings of midnight in mktime64()
X.509: Fix leap year handling again
PKCS#7: fix unitialized boolean 'want'
firmware: change kernel read fail to dev_dbg()
KEYS: Use the symbol value for list size, updated by scripts/insert-sys-cert
KEYS: Reserve an extra certificate symbol for inserting without recompiling
modsign: hide openssl output in silent builds
tpm_tis: fix build warning with tpm_tis_resume
ima: require signed IMA policy
ima: measure and appraise the IMA policy itself
ima: load policy using path
...
Make the identifier public key and digest algorithm fields text instead of
enum.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Move the RSA EMSA-PKCS1-v1_5 encoding from the asymmetric-key public_key
subtype to the rsa crypto module's pkcs1pad template. This means that the
public_key subtype no longer has any dependencies on public key type.
To make this work, the following changes have been made:
(1) The rsa pkcs1pad template is now used for RSA keys. This strips off the
padding and returns just the message hash.
(2) In a previous patch, the pkcs1pad template gained an optional second
parameter that, if given, specifies the hash used. We now give this,
and pkcs1pad checks the encoded message E(M) for the EMSA-PKCS1-v1_5
encoding and verifies that the correct digest OID is present.
(3) The crypto driver in crypto/asymmetric_keys/rsa.c is now reduced to
something that doesn't care about what the encryption actually does
and and has been merged into public_key.c.
(4) CONFIG_PUBLIC_KEY_ALGO_RSA is gone. Module signing must set
CONFIG_CRYPTO_RSA=y instead.
Thoughts:
(*) Should the encoding style (eg. raw, EMSA-PKCS1-v1_5) also be passed to
the padding template? Should there be multiple padding templates
registered that share most of the code?
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
After digsig_asymmetric.c is converted the MPIs can be now
safely removed from the public_key_signature structure.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David Howells <dhowells@redhat.com>
The associated data handling with the kernel crypto API has been
updated. This needs to be reflected in the documentation.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reference the new akcipher API calls in the kernel crypto API DocBook.
Also, fix the comments in the akcipher.h file: double dashes do not look
good in the DocBook; fix a typo.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The patch centralizes the XTS key check logic into the service function
xts_check_key which is invoked from the different XTS implementations.
With this, the XTS implementations in ARM, ARM64, PPC and S390 have now
a sanity check for the XTS keys similar to the other arches.
In addition, this service function received a check to ensure that the
key != the tweak key which is mandated by FIPS 140-2 IG A.9. As the
check is not present in the standards defining XTS, it is only enforced
in FIPS mode of the kernel.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch converts the module verification code to the new akcipher API.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David Howells <dhowells@redhat.com>
After digsig_asymmetric.c is converted the MPIs can be now
safely removed from the public_key_signature structure.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch converts the module verification code to the new akcipher API.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Move the helper function to common header for everybody to use.
changes in v2:
- move the helper to crypto/internal/aead.h
instead of crypto/aead.h
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch removes all traces of the crypto_hash interface, now
that everyone has switched over to shash or ahash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds helpers to retrieve the alg name and driver name
of crypto_shash and crypto_ahash objects.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now block cipher engines need to implement and maintain their own queue/thread
for processing requests, moreover currently helpers provided for only the queue
itself (in crypto_enqueue_request() and crypto_dequeue_request()) but they
don't help with the mechanics of driving the hardware (things like running the
request immediately, DMA map it or providing a thread to process the queue in)
even though a lot of that code really shouldn't vary that much from device to
device.
Thus this patch provides a mechanism for pushing requests to the hardware
as it becomes free that drivers could use. And this framework is patterned
on the SPI code and has worked out well there.
(https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/
drivers/spi/spi.c?id=ffbbdd21329f3e15eeca6df2d4bc11c04d9d91c0)
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch introduces crypto_queue_len() helper function to help to get the
queue length in the crypto queue list now.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the helper crypto_skcipher_driver_name which returns
the driver name of the alg object for a given tfm. This is needed by
ecryptfs.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As the size of an skcipher_request is variable, it's awkward to
zero it explicitly. This patch adds a helper to do that which
should be used when it is created on the stack.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As the size of an ahash_request or shash_desc is variable, it's
awkward to zero them explicitly. This patch adds helpers to do
that which should be used when they are created on the stack.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The newly released FIPS 140-2 IG 9.8 specifies that for SP800-90A
compliant DRBGs, the FIPS 140-2 continuous random number generator test
is not required any more.
This patch removes the test and all associated data structures.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
While converting ecryptfs over to skcipher I found that it needs
to pick a default key size if one isn't given. Rather than having
it poke into the guts of the algorithm to get max_keysize, let's
provide a helper that is meant to give a sane default (just in
case we ever get an algorithm that has no maximum key size).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto fixes from Herbert Xu:
"This fixes the following issues:
API:
- A large number of bug fixes for the af_alg interface, credit goes
to Dmitry Vyukov for discovering and reporting these issues.
Algorithms:
- sw842 needs to select crc32.
- The soft dependency on crc32c is now in the correct spot.
Drivers:
- The atmel AES driver needs HAS_DMA.
- The atmel AES driver was a missing break statement, fortunately
it's only a debug function.
- A number of bug fixes for the Intel qat driver"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (24 commits)
crypto: algif_skcipher - sendmsg SG marking is off by one
crypto: crc32c - Fix crc32c soft dependency
crypto: algif_skcipher - Load TX SG list after waiting
crypto: atmel-aes - Add missing break to atmel_aes_reg_name
crypto: algif_skcipher - Fix race condition in skcipher_check_key
crypto: algif_hash - Fix race condition in hash_check_key
crypto: CRYPTO_DEV_ATMEL_AES should depend on HAS_DMA
lib: sw842: select crc32
crypto: af_alg - Forbid bind(2) when nokey child sockets are present
crypto: algif_skcipher - Remove custom release parent function
crypto: algif_hash - Remove custom release parent function
crypto: af_alg - Allow af_af_alg_release_parent to be called on nokey path
crypto: qat - update init_esram for C3xxx dev type
crypto: qat - fix timeout issues
crypto: qat - remove to call get_sram_bar_id for qat_c3xxx
crypto: algif_skcipher - Add key check exception for cipher_null
crypto: skcipher - Add crypto_skcipher_has_setkey
crypto: algif_hash - Require setkey before accept(2)
crypto: hash - Add crypto_ahash_has_setkey
crypto: algif_skcipher - Add nokey compatibility path
...
This patch allows af_alg_release_parent to be called even for
nokey sockets.
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a way for skcipher users to determine whether a key
is required by a transform.
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a way for ahash users to determine whether a key
is required by a crypto_ahash transform.
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a compatibility path to support old applications
that do acept(2) before setkey.
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Each af_alg parent socket obtained by socket(2) corresponds to a
tfm object once bind(2) has succeeded. An accept(2) call on that
parent socket creates a context which then uses the tfm object.
Therefore as long as any child sockets created by accept(2) exist
the parent socket must not be modified or freed.
This patch guarantees this by using locks and a reference count
on the parent socket. Any attempt to modify the parent socket will
fail with EBUSY.
Cc: stable@vger.kernel.org
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull security subsystem updates from James Morris:
- EVM gains support for loading an x509 cert from the kernel
(EVM_LOAD_X509), into the EVM trusted kernel keyring.
- Smack implements 'file receive' process-based permission checking for
sockets, rather than just depending on inode checks.
- Misc enhancments for TPM & TPM2.
- Cleanups and bugfixes for SELinux, Keys, and IMA.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (41 commits)
selinux: Inode label revalidation performance fix
KEYS: refcount bug fix
ima: ima_write_policy() limit locking
IMA: policy can be updated zero times
selinux: rate-limit netlink message warnings in selinux_nlmsg_perm()
selinux: export validatetrans decisions
gfs2: Invalid security labels of inodes when they go invalid
selinux: Revalidate invalid inode security labels
security: Add hook to invalidate inode security labels
selinux: Add accessor functions for inode->i_security
security: Make inode argument of inode_getsecid non-const
security: Make inode argument of inode_getsecurity non-const
selinux: Remove unused variable in selinux_inode_init_security
keys, trusted: seal with a TPM2 authorization policy
keys, trusted: select hash algorithm for TPM2 chips
keys, trusted: fix: *do not* allow duplicate key options
tpm_ibmvtpm: properly handle interrupted packet receptions
tpm_tis: Tighten IRQ auto-probing
tpm_tis: Refactor the interrupt setup
tpm_tis: Get rid of the duplicate IRQ probing code
...
Some crypto drivers cannot process empty data message and return a
precalculated hash for md5/sha1/sha224/sha256.
This patch add thoses precalculated hash in include/crypto.
Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Added 'hash=' option for selecting the hash algorithm for add_key()
syscall and documentation for it.
Added entry for sm3-256 to the following tables in order to support
TPM_ALG_SM3_256:
* hash_algo_name
* hash_digest_size
Includes support for the following hash algorithms:
* sha1
* sha256
* sha384
* sha512
* sm3-256
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
This patch adds PKCS#1 v1.5 standard RSA padding as a separate template.
This way an RSA cipher with padding can be obtained by instantiating
"pkcs1pad(rsa)". The reason for adding this is that RSA is almost
never used without this padding (or OAEP) so it will be needed for
either certificate work in the kernel or the userspace, and I also hear
that it is likely implemented by hardware RSA in which case hardware
implementations of the whole of pkcs1pad(rsa) can be provided.
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add a struct akcipher_instance and struct akcipher_spawn similar to
how AEAD declares them and the macros for converting to/from
crypto_instance/crypto_spawn. Also add register functions to
avoid exposing crypto_akcipher_type.
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Fix 21 occurrences of this kernel-doc warning in <crypto/aead.h>:
..//include/crypto/aead.h:149: warning: No description found for parameter 'base'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull security subsystem update from James Morris:
"This is mostly maintenance updates across the subsystem, with a
notable update for TPM 2.0, and addition of Jarkko Sakkinen as a
maintainer of that"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (40 commits)
apparmor: clarify CRYPTO dependency
selinux: Use a kmem_cache for allocation struct file_security_struct
selinux: ioctl_has_perm should be static
selinux: use sprintf return value
selinux: use kstrdup() in security_get_bools()
selinux: use kmemdup in security_sid_to_context_core()
selinux: remove pointless cast in selinux_inode_setsecurity()
selinux: introduce security_context_str_to_sid
selinux: do not check open perm on ftruncate call
selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default
KEYS: Merge the type-specific data with the payload data
KEYS: Provide a script to extract a module signature
KEYS: Provide a script to extract the sys cert list from a vmlinux file
keys: Be more consistent in selection of union members used
certs: add .gitignore to stop git nagging about x509_certificate_list
KEYS: use kvfree() in add_key
Smack: limited capability for changing process label
TPM: remove unnecessary little endian conversion
vTPM: support little endian guests
char: Drop owner assignment from i2c_driver
...
This patch adds the missing helper crypto_ahash_blocksize which
returns the block size of an ahash algorithm.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Setkey function has been split into set_priv_key and set_pub_key.
Akcipher requests takes sgl for src and dst instead of void *.
Users of the API i.e. two existing RSA implementation and
test mgr code have been updated accordingly.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull security subsystem updates from James Morris:
"Highlights:
- PKCS#7 support added to support signed kexec, also utilized for
module signing. See comments in 3f1e1bea.
** NOTE: this requires linking against the OpenSSL library, which
must be installed, e.g. the openssl-devel on Fedora **
- Smack
- add IPv6 host labeling; ignore labels on kernel threads
- support smack labeling mounts which use binary mount data
- SELinux:
- add ioctl whitelisting (see
http://kernsec.org/files/lss2015/vanderstoep.pdf)
- fix mprotect PROT_EXEC regression caused by mm change
- Seccomp:
- add ptrace options for suspend/resume"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (57 commits)
PKCS#7: Add OIDs for sha224, sha284 and sha512 hash algos and use them
Documentation/Changes: Now need OpenSSL devel packages for module signing
scripts: add extract-cert and sign-file to .gitignore
modsign: Handle signing key in source tree
modsign: Use if_changed rule for extracting cert from module signing key
Move certificate handling to its own directory
sign-file: Fix warning about BIO_reset() return value
PKCS#7: Add MODULE_LICENSE() to test module
Smack - Fix build error with bringup unconfigured
sign-file: Document dependency on OpenSSL devel libraries
PKCS#7: Appropriately restrict authenticated attributes and content type
KEYS: Add a name for PKEY_ID_PKCS7
PKCS#7: Improve and export the X.509 ASN.1 time object decoder
modsign: Use extract-cert to process CONFIG_SYSTEM_TRUSTED_KEYS
extract-cert: Cope with multiple X.509 certificates in a single file
sign-file: Generate CMS message as signature instead of PKCS#7
PKCS#7: Support CMS messages also [RFC5652]
X.509: Change recorded SKID & AKID to not include Subject or Issuer
PKCS#7: Check content type and versions
MAINTAINERS: The keyrings mailing list has moved
...
Pull SG updates from Jens Axboe:
"This contains a set of scatter-gather related changes/fixes for 4.3:
- Add support for limited chaining of sg tables even for
architectures that do not set ARCH_HAS_SG_CHAIN. From Christoph.
- Add sg chain support to target_rd. From Christoph.
- Fixup open coded sg->page_link in crypto/omap-sham. From
Christoph.
- Fixup open coded crypto ->page_link manipulation. From Dan.
- Also from Dan, automated fixup of manual sg_unmark_end()
manipulations.
- Also from Dan, automated fixup of open coded sg_phys()
implementations.
- From Robert Jarzmik, addition of an sg table splitting helper that
drivers can use"
* 'for-4.3/sg' of git://git.kernel.dk/linux-block:
lib: scatterlist: add sg splitting function
scatterlist: use sg_phys()
crypto/omap-sham: remove an open coded access to ->page_link
scatterlist: remove open coded sg_unmark_end instances
crypto: replace scatterwalk_sg_chain with sg_chain
target/rd: always chain S/G list
scatterlist: allow limited chaining without ARCH_HAS_SG_CHAIN
This patch adds the helper AHASH_REQUEST_ON_STACK for those users
of ahash that are synchronous only.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch introduces the crypto skcipher interface which aims
to replace both blkcipher and ablkcipher.
It's very similar to the existing ablkcipher interface. The
main difference is the removal of the givcrypt interface. In
order to make the transition easier for blkcipher users, there
is a helper SKCIPHER_REQUEST_ON_STACK which can be used to place
a request on the stack for synchronous transforms.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
[hch: split from a larger patch by Dan]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jens Axboe <axboe@fb.com>
Now that the AEAD conversion is complete we can rip out the old
AEAD interafce and associated code.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the helpers aead_init_geniv and aead_exit_geniv
which are type-safe and intended the replace the existing geniv
init/exit helpers.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
A PKCS#7 or CMS message can have per-signature authenticated attributes
that are digested as a lump and signed by the authorising key for that
signature. If such attributes exist, the content digest isn't itself
signed, but rather it is included in a special authattr which then
contributes to the signature.
Further, we already require the master message content type to be
pkcs7_signedData - but there's also a separate content type for the data
itself within the SignedData object and this must be repeated inside the
authattrs for each signer [RFC2315 9.2, RFC5652 11.1].
We should really validate the authattrs if they exist or forbid them
entirely as appropriate. To this end:
(1) Alter the PKCS#7 parser to reject any message that has more than one
signature where at least one signature has authattrs and at least one
that does not.
(2) Validate authattrs if they are present and strongly restrict them.
Only the following authattrs are permitted and all others are
rejected:
(a) contentType. This is checked to be an OID that matches the
content type in the SignedData object.
(b) messageDigest. This must match the crypto digest of the data.
(c) signingTime. If present, we check that this is a valid, parseable
UTCTime or GeneralTime and that the date it encodes fits within
the validity window of the matching X.509 cert.
(d) S/MIME capabilities. We don't check the contents.
(e) Authenticode SP Opus Info. We don't check the contents.
(f) Authenticode Statement Type. We don't check the contents.
The message is rejected if (a) or (b) are missing. If the message is
an Authenticode type, the message is rejected if (e) is missing; if
not Authenticode, the message is rejected if (d) - (f) are present.
The S/MIME capabilities authattr (d) unfortunately has to be allowed
to support kernels already signed by the pesign program. This only
affects kexec. sign-file suppresses them (CMS_NOSMIMECAP).
The message is also rejected if an authattr is given more than once or
if it contains more than one element in its set of values.
(3) Add a parameter to pkcs7_verify() to select one of the following
restrictions and pass in the appropriate option from the callers:
(*) VERIFYING_MODULE_SIGNATURE
This requires that the SignedData content type be pkcs7-data and
forbids authattrs. sign-file sets CMS_NOATTR. We could be more
flexible and permit authattrs optionally, but only permit minimal
content.
(*) VERIFYING_FIRMWARE_SIGNATURE
This requires that the SignedData content type be pkcs7-data and
requires authattrs. In future, this will require an attribute
holding the target firmware name in addition to the minimal set.
(*) VERIFYING_UNSPECIFIED_SIGNATURE
This requires that the SignedData content type be pkcs7-data but
allows either no authattrs or only permits the minimal set.
(*) VERIFYING_KEXEC_PE_SIGNATURE
This only supports the Authenticode SPC_INDIRECT_DATA content type
and requires at least an SpcSpOpusInfo authattr in addition to the
minimal set. It also permits an SPC_STATEMENT_TYPE authattr (and
an S/MIME capabilities authattr because the pesign program doesn't
remove these).
(*) VERIFYING_KEY_SIGNATURE
(*) VERIFYING_KEY_SELF_SIGNATURE
These are invalid in this context but are included for later use
when limiting the use of X.509 certs.
(4) The pkcs7_test key type is given a module parameter to select between
the above options for testing purposes. For example:
echo 1 >/sys/module/pkcs7_test_key/parameters/usage
keyctl padd pkcs7_test foo @s </tmp/stuff.pkcs7
will attempt to check the signature on stuff.pkcs7 as if it contains a
firmware blob (1 being VERIFYING_FIRMWARE_SIGNATURE).
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>
Provide a utility that:
(1) Digests a module using the specified hash algorithm (typically sha256).
[The digest can be dumped into a file by passing the '-d' flag]
(2) Generates a PKCS#7 message that:
(a) Has detached data (ie. the module content).
(b) Is signed with the specified private key.
(c) Refers to the specified X.509 certificate.
(d) Has an empty X.509 certificate list.
[The PKCS#7 message can be dumped into a file by passing the '-p' flag]
(3) Generates a signed module by concatenating the old module, the PKCS#7
message, a descriptor and a magic string. The descriptor contains the
size of the PKCS#7 message and indicates the id_type as PKEY_ID_PKCS7.
(4) Either writes the signed module to the specified destination or renames
it over the source module.
This allows module signing to reuse the PKCS#7 handling code that was added
for PE file parsing for signed kexec.
Note that the utility is written in C and must be linked against the OpenSSL
crypto library.
Note further that I have temporarily dropped support for handling externally
created signatures until we can work out the best way to do those. Hopefully,
whoever creates the signature can give me a PKCS#7 certificate.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Vivek Goyal <vgoyal@redhat.com>