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2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36Thomas Gleixner1-5/+1
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>
2018-10-26KEYS: Make the X.509 and PKCS7 parsers supply the sig encoding type [ver #2]David Howells1-0/+1
Make the X.509 and PKCS7 parsers fill in the signature encoding type field recently added to the public_key_signature struct. 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>
2018-04-07kbuild: rename *-asn1.[ch] to *.asn1.[ch]Masahiro Yamada1-1/+1
Our convention is to distinguish file types by suffixes with a period as a separator. *-asn1.[ch] is a different pattern from other generated sources such as *.lex.c, *.tab.[ch], *.dtb.S, etc. More confusing, files with '-asn1.[ch]' are generated files, but '_asn1.[ch]' are checked-in files: net/netfilter/nf_conntrack_h323_asn1.c include/linux/netfilter/nf_conntrack_h323_asn1.h include/linux/sunrpc/gss_asn1.h Rename generated files to *.asn1.[ch] for consistency. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-08pkcs7: return correct error code if pkcs7_check_authattrs() failsEric Biggers1-1/+3
If pkcs7_check_authattrs() returns an error code, we should pass that error code on, rather than using ENOMEM. Fixes: 99db44350672 ("PKCS#7: Appropriately restrict authenticated attributes and content type") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com>
2017-11-15pkcs7: Set the module licence to prevent taintingDavid Howells1-0/+5
Set the module licence to prevent the kernel from being tainted if loaded as a module. Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18pkcs7: Prevent NULL pointer dereference, since sinfo is not always set.Eric Sesterhenn1-0/+3
The ASN.1 parser does not necessarily set the sinfo field, this patch prevents a NULL pointer dereference on broken input. Fixes: 99db44350672 ("PKCS#7: Appropriately restrict authenticated attributes and content type") Signed-off-by: Eric Sesterhenn <eric.sesterhenn@x41-dsec.de> Signed-off-by: David Howells <dhowells@redhat.com> cc: stable@vger.kernel.org # 4.3+
2016-04-06KEYS: Generalise system_verify_data() to provide access to internal contentDavid Howells1-10/+11
Generalise system_verify_data() to provide access to internal content through a callback. This allows all the PKCS#7 stuff to be hidden inside this function and removed from the PE file parser and the PKCS#7 test key. If external content is not required, NULL should be passed as data to the function. If the callback is not required, that can be set to NULL. The function is now called verify_pkcs7_signature() to contrast with verify_pefile_signature() and the definitions of both have been moved into linux/verification.h along with the key_being_used_for enum. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-06PKCS#7: Make the signature a pointer rather than embedding itDavid Howells1-15/+23
Point to the public_key_signature struct from the pkcs7_signed_info struct rather than embedding it. This makes the code consistent with the X.509 signature handling and makes it possible to have a common cleanup function. We also save a copy of the digest in the signature without sharing the memory with the crypto layer metadata. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-03X.509: Make algo identifiers text instead of enumDavid Howells1-10/+8
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>
2016-02-29PKCS#7: fix unitialized boolean 'want'Colin Ian King1-1/+1
The boolean want is not initialized and hence garbage. The default should be false (later it is only set to true on tne sinfo->authattrs check). Found with static analysis using CoverityScan Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David Howells <dhowells@redhat.com>
2016-02-10crypto: KEYS: convert public key and digsig asym to the akcipher apiTadeusz Struk1-7/+5
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>
2016-01-25PKCS#7: Don't require SpcSpOpusInfo in Authenticode pkcs7 signaturesPeter Jones1-3/+1
Dave Young reported: > Hi, > > I saw the warning "Missing required AuthAttr" when testing kexec, > known issue? Idea about how to fix it? > > The kernel is latest linus tree plus sevral patches from Toshi to > cleanup io resource structure. > > in function pkcs7_sig_note_set_of_authattrs(): > if (!test_bit(sinfo_has_content_type, &sinfo->aa_set) || > !test_bit(sinfo_has_message_digest, &sinfo->aa_set) || > (ctx->msg->data_type == OID_msIndirectData && > !test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set))) { > pr_warn("Missing required AuthAttr\n"); > return -EBADMSG; > } > > The third condition below is true: > (ctx->msg->data_type == OID_msIndirectData && > !test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) > > I signed the kernel with redhat test key like below: > pesign -c 'Red Hat Test Certificate' -i arch/x86/boot/bzImage -o /boot/vmlinuz-4.4.0-rc8+ -s --force And right he is! The Authenticode specification is a paragon amongst technical documents, and has this pearl of wisdom to offer: --------------------------------- Authenticode-Specific SignerInfo UnauthenticatedAttributes Structures The following Authenticode-specific data structures are present in SignerInfo authenticated attributes. SpcSpOpusInfo SpcSpOpusInfo is identified by SPC_SP_OPUS_INFO_OBJID (1.3.6.1.4.1.311.2.1.12) and is defined as follows: SpcSpOpusInfo ::= SEQUENCE { programName [0] EXPLICIT SpcString OPTIONAL, moreInfo [1] EXPLICIT SpcLink OPTIONAL, } --#public-- SpcSpOpusInfo has two fields: programName This field contains the program description: If publisher chooses not to specify a description, the SpcString structure contains a zero-length program name. If the publisher chooses to specify a description, the SpcString structure contains a Unicode string. moreInfo This field is set to an SPCLink structure that contains a URL for a Web site with more information about the signer. The URL is an ASCII string. --------------------------------- Which is to say that this is an optional *unauthenticated* field which may be present in the Authenticated Attribute list. This is not how pkcs7 is supposed to work, so when David implemented this, he didn't appreciate the subtlety the original spec author was working with, and missed the part of the sublime prose that says this Authenticated Attribute is an Unauthenticated Attribute. As a result, the code in question simply takes as given that the Authenticated Attributes should be authenticated. But this one should not, individually. Because it says it's not authenticated. It still has to hash right so the TBS digest is correct. So it is both authenticated and unauthenticated, all at once. Truly, a wonder of technical accomplishment. Additionally, pesign's implementation has always attempted to be compatible with the signatures emitted from contemporary versions of Microsoft's signtool.exe. During the initial implementation, Microsoft signatures always produced the same values for SpcSpOpusInfo - {U"Microsoft Windows", "http://www.microsoft.com"} - without regard to who the signer was. Sometime between Windows 8 and Windows 8.1 they stopped including the field in their signatures altogether, and as such pesign stopped producing them in commits c0c4da6 and d79cb0c, sometime around June of 2012. The theory here is that anything that breaks with pesign signatures would also be breaking with signtool.exe sigs as well, and that'll be a more noticed problem for firmwares parsing it, so it'll get fixed. The fact that we've done exactly this bug in Linux code is first class, grade A irony. So anyway, we should not be checking this field for presence or any particular value: if the field exists, it should be at the right place, but aside from that, as long as the hash matches the field is good. Signed-off-by: Peter Jones <pjones@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-09-01PKCS#7: Add OIDs for sha224, sha284 and sha512 hash algos and use themDavid Howells1-0/+8
Add OIDs for sha224, sha284 and sha512 hash algos and use them to select the hashing algorithm. Without this, something like the following error might get written to dmesg: [ 31.829322] PKCS7: Unknown OID: [32] 2.16.840.1.101.3.4.2.3 [ 31.829328] PKCS7: Unknown OID: [180] 2.16.840.1.101.3.4.2.3 [ 31.829330] Unsupported digest algo: 55 Where the 55 on the third line is OID__NR indicating an unknown OID. Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Signed-off-by: David Howells <dhowells@redhat.com> Tested-By: Valdis Kletnieks <valdis.kletnieks@vt.edu> Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-08-12PKCS#7: Appropriately restrict authenticated attributes and content typeDavid Howells1-6/+132
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>
2015-08-12PKCS#7: Support CMS messages also [RFC5652]David Howells1-7/+55
Since CMS is an evolution of PKCS#7, with much of the ASN.1 being compatible, add support for CMS signed-data messages also [RFC5652 sec 5]. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-By: David Woodhouse <David.Woodhouse@intel.com>
2015-08-12PKCS#7: Check content type and versionsDavid Howells1-1/+74
We only support PKCS#7 signed-data [RFC2315 sec 9] content at the top level, so reject anything else. Further, check that the version numbers in SignedData and SignerInfo are 1 in both cases. Note that we don't restrict the inner content type. In the PKCS#7 code we don't parse the data attached there, but merely verify the signature over it. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-By: David Woodhouse <David.Woodhouse@intel.com>
2014-09-16KEYS: Overhaul key identification when searching for asymmetric keysDavid Howells1-11/+27
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>
2014-09-16PKCS#7: Fix the parser cleanup to drain parsed out X.509 certsDavid Howells1-20/+19
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>
2014-09-16PKCS#7: Provide a single place to do signed info block freeingDavid Howells1-9/+15
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>
2014-07-08PKCS#7: Implement a parser [RFC 2315]David Howells1-0/+396
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>