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>
这个提交包含在:
@@ -33,7 +33,7 @@ config X509_CERTIFICATE_PARSER
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select ASN1
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select OID_REGISTRY
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help
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This option procides support for parsing X.509 format blobs for key
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This option provides support for parsing X.509 format blobs for key
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data and provides the ability to instantiate a crypto key from a
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public key packet found inside the certificate.
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@@ -59,4 +59,13 @@ config PKCS7_TEST_KEY
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This is intended for testing the PKCS#7 parser.
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config SIGNED_PE_FILE_VERIFICATION
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bool "Support for PE file signature verification"
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depends on PKCS7_MESSAGE_PARSER=y
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select ASN1
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select OID_REGISTRY
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help
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This option provides support for verifying the signature(s) on a
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signed PE binary.
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endif # ASYMMETRIC_KEY_TYPE
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@@ -47,3 +47,18 @@ clean-files += pkcs7-asn1.c pkcs7-asn1.h
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obj-$(CONFIG_PKCS7_TEST_KEY) += pkcs7_test_key.o
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pkcs7_test_key-y := \
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pkcs7_key_type.o
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#
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# Signed PE binary-wrapped key handling
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#
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obj-$(CONFIG_SIGNED_PE_FILE_VERIFICATION) += verify_signed_pefile.o
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verify_signed_pefile-y := \
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verify_pefile.o \
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mscode_parser.o \
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mscode-asn1.o
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$(obj)/mscode_parser.o: $(obj)/mscode-asn1.h $(obj)/mscode-asn1.h
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$(obj)/mscode-asn1.o: $(obj)/mscode-asn1.c $(obj)/mscode-asn1.h
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clean-files += mscode-asn1.c mscode-asn1.h
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@@ -0,0 +1,28 @@
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--- Microsoft individual code signing data blob parser
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---
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--- Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
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--- Written by David Howells (dhowells@redhat.com)
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---
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--- This program is free software; you can redistribute it and/or
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--- modify it under the terms of the GNU General Public Licence
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--- as published by the Free Software Foundation; either version
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--- 2 of the Licence, or (at your option) any later version.
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---
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MSCode ::= SEQUENCE {
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type SEQUENCE {
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contentType ContentType,
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parameters ANY
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},
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content SEQUENCE {
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digestAlgorithm DigestAlgorithmIdentifier,
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digest OCTET STRING ({ mscode_note_digest })
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}
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}
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ContentType ::= OBJECT IDENTIFIER ({ mscode_note_content_type })
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DigestAlgorithmIdentifier ::= SEQUENCE {
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algorithm OBJECT IDENTIFIER ({ mscode_note_digest_algo }),
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parameters ANY OPTIONAL
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}
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@@ -0,0 +1,126 @@
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/* Parse a Microsoft Individual Code Signing blob
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*
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* Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public Licence
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* as published by the Free Software Foundation; either version
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* 2 of the Licence, or (at your option) any later version.
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*/
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#define pr_fmt(fmt) "MSCODE: "fmt
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/err.h>
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#include <linux/oid_registry.h>
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#include <crypto/pkcs7.h>
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#include "verify_pefile.h"
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#include "mscode-asn1.h"
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/*
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* Parse a Microsoft Individual Code Signing blob
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*/
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int mscode_parse(struct pefile_context *ctx)
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{
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const void *content_data;
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size_t data_len;
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int ret;
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ret = pkcs7_get_content_data(ctx->pkcs7, &content_data, &data_len, 1);
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if (ret) {
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pr_debug("PKCS#7 message does not contain data\n");
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return ret;
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}
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pr_devel("Data: %zu [%*ph]\n", data_len, (unsigned)(data_len),
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content_data);
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return asn1_ber_decoder(&mscode_decoder, ctx, content_data, data_len);
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}
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/*
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* Check the content type OID
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*/
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int mscode_note_content_type(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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enum OID oid;
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oid = look_up_OID(value, vlen);
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if (oid == OID__NR) {
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char buffer[50];
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sprint_oid(value, vlen, buffer, sizeof(buffer));
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pr_err("Unknown OID: %s\n", buffer);
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return -EBADMSG;
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}
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/*
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* pesign utility had a bug where it was putting
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* OID_msIndividualSPKeyPurpose instead of OID_msPeImageDataObjId
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* So allow both OIDs.
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*/
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if (oid != OID_msPeImageDataObjId &&
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oid != OID_msIndividualSPKeyPurpose) {
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pr_err("Unexpected content type OID %u\n", oid);
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return -EBADMSG;
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}
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return 0;
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}
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/*
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* Note the digest algorithm OID
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*/
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int mscode_note_digest_algo(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct pefile_context *ctx = context;
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char buffer[50];
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enum OID oid;
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oid = look_up_OID(value, vlen);
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switch (oid) {
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case OID_md4:
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ctx->digest_algo = HASH_ALGO_MD4;
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break;
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case OID_md5:
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ctx->digest_algo = HASH_ALGO_MD5;
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break;
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case OID_sha1:
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ctx->digest_algo = HASH_ALGO_SHA1;
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break;
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case OID_sha256:
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ctx->digest_algo = HASH_ALGO_SHA256;
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break;
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case OID__NR:
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sprint_oid(value, vlen, buffer, sizeof(buffer));
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pr_err("Unknown OID: %s\n", buffer);
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return -EBADMSG;
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default:
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pr_err("Unsupported content type: %u\n", oid);
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return -ENOPKG;
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}
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return 0;
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}
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/*
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* Note the digest we're guaranteeing with this certificate
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*/
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int mscode_note_digest(void *context, size_t hdrlen,
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unsigned char tag,
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const void *value, size_t vlen)
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{
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struct pefile_context *ctx = context;
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ctx->digest = value;
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ctx->digest_len = vlen;
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return 0;
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}
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@@ -0,0 +1,457 @@
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/* Parse a signed PE binary
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*
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* Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public Licence
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* as published by the Free Software Foundation; either version
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* 2 of the Licence, or (at your option) any later version.
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*/
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#define pr_fmt(fmt) "PEFILE: "fmt
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/err.h>
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#include <linux/pe.h>
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#include <linux/asn1.h>
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#include <crypto/pkcs7.h>
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#include <crypto/hash.h>
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#include "verify_pefile.h"
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/*
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* Parse a PE binary.
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*/
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static int pefile_parse_binary(const void *pebuf, unsigned int pelen,
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struct pefile_context *ctx)
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{
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const struct mz_hdr *mz = pebuf;
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const struct pe_hdr *pe;
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const struct pe32_opt_hdr *pe32;
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const struct pe32plus_opt_hdr *pe64;
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const struct data_directory *ddir;
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const struct data_dirent *dde;
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const struct section_header *secs, *sec;
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size_t cursor, datalen = pelen;
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kenter("");
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#define chkaddr(base, x, s) \
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do { \
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if ((x) < base || (s) >= datalen || (x) > datalen - (s)) \
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return -ELIBBAD; \
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} while (0)
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chkaddr(0, 0, sizeof(*mz));
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if (mz->magic != MZ_MAGIC)
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return -ELIBBAD;
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cursor = sizeof(*mz);
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chkaddr(cursor, mz->peaddr, sizeof(*pe));
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pe = pebuf + mz->peaddr;
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if (pe->magic != PE_MAGIC)
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return -ELIBBAD;
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cursor = mz->peaddr + sizeof(*pe);
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chkaddr(0, cursor, sizeof(pe32->magic));
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pe32 = pebuf + cursor;
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pe64 = pebuf + cursor;
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switch (pe32->magic) {
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case PE_OPT_MAGIC_PE32:
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chkaddr(0, cursor, sizeof(*pe32));
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ctx->image_checksum_offset =
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(unsigned long)&pe32->csum - (unsigned long)pebuf;
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ctx->header_size = pe32->header_size;
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cursor += sizeof(*pe32);
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ctx->n_data_dirents = pe32->data_dirs;
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break;
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case PE_OPT_MAGIC_PE32PLUS:
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chkaddr(0, cursor, sizeof(*pe64));
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ctx->image_checksum_offset =
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(unsigned long)&pe64->csum - (unsigned long)pebuf;
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ctx->header_size = pe64->header_size;
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cursor += sizeof(*pe64);
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ctx->n_data_dirents = pe64->data_dirs;
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break;
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default:
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pr_debug("Unknown PEOPT magic = %04hx\n", pe32->magic);
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return -ELIBBAD;
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}
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pr_debug("checksum @ %x\n", ctx->image_checksum_offset);
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pr_debug("header size = %x\n", ctx->header_size);
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if (cursor >= ctx->header_size || ctx->header_size >= datalen)
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return -ELIBBAD;
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if (ctx->n_data_dirents > (ctx->header_size - cursor) / sizeof(*dde))
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return -ELIBBAD;
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ddir = pebuf + cursor;
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cursor += sizeof(*dde) * ctx->n_data_dirents;
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ctx->cert_dirent_offset =
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(unsigned long)&ddir->certs - (unsigned long)pebuf;
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ctx->certs_size = ddir->certs.size;
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if (!ddir->certs.virtual_address || !ddir->certs.size) {
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pr_debug("Unsigned PE binary\n");
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return -EKEYREJECTED;
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}
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chkaddr(ctx->header_size, ddir->certs.virtual_address,
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ddir->certs.size);
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ctx->sig_offset = ddir->certs.virtual_address;
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ctx->sig_len = ddir->certs.size;
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pr_debug("cert = %x @%x [%*ph]\n",
|
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ctx->sig_len, ctx->sig_offset,
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ctx->sig_len, pebuf + ctx->sig_offset);
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||||
|
||||
ctx->n_sections = pe->sections;
|
||||
if (ctx->n_sections > (ctx->header_size - cursor) / sizeof(*sec))
|
||||
return -ELIBBAD;
|
||||
ctx->secs = secs = pebuf + cursor;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Check and strip the PE wrapper from around the signature and check that the
|
||||
* remnant looks something like PKCS#7.
|
||||
*/
|
||||
static int pefile_strip_sig_wrapper(const void *pebuf,
|
||||
struct pefile_context *ctx)
|
||||
{
|
||||
struct win_certificate wrapper;
|
||||
const u8 *pkcs7;
|
||||
|
||||
if (ctx->sig_len < sizeof(wrapper)) {
|
||||
pr_debug("Signature wrapper too short\n");
|
||||
return -ELIBBAD;
|
||||
}
|
||||
|
||||
memcpy(&wrapper, pebuf + ctx->sig_offset, sizeof(wrapper));
|
||||
pr_debug("sig wrapper = { %x, %x, %x }\n",
|
||||
wrapper.length, wrapper.revision, wrapper.cert_type);
|
||||
|
||||
/* Both pesign and sbsign round up the length of certificate table
|
||||
* (in optional header data directories) to 8 byte alignment.
|
||||
*/
|
||||
if (round_up(wrapper.length, 8) != ctx->sig_len) {
|
||||
pr_debug("Signature wrapper len wrong\n");
|
||||
return -ELIBBAD;
|
||||
}
|
||||
if (wrapper.revision != WIN_CERT_REVISION_2_0) {
|
||||
pr_debug("Signature is not revision 2.0\n");
|
||||
return -ENOTSUPP;
|
||||
}
|
||||
if (wrapper.cert_type != WIN_CERT_TYPE_PKCS_SIGNED_DATA) {
|
||||
pr_debug("Signature certificate type is not PKCS\n");
|
||||
return -ENOTSUPP;
|
||||
}
|
||||
|
||||
/* Looks like actual pkcs signature length is in wrapper->length.
|
||||
* size obtained from data dir entries lists the total size of
|
||||
* certificate table which is also aligned to octawrod boundary.
|
||||
*
|
||||
* So set signature length field appropriately.
|
||||
*/
|
||||
ctx->sig_len = wrapper.length;
|
||||
ctx->sig_offset += sizeof(wrapper);
|
||||
ctx->sig_len -= sizeof(wrapper);
|
||||
if (ctx->sig_len == 0) {
|
||||
pr_debug("Signature data missing\n");
|
||||
return -EKEYREJECTED;
|
||||
}
|
||||
|
||||
/* What's left should a PKCS#7 cert */
|
||||
pkcs7 = pebuf + ctx->sig_offset;
|
||||
if (pkcs7[0] == (ASN1_CONS_BIT | ASN1_SEQ)) {
|
||||
if (pkcs7[1] == 0x82 &&
|
||||
pkcs7[2] == (((ctx->sig_len - 4) >> 8) & 0xff) &&
|
||||
pkcs7[3] == ((ctx->sig_len - 4) & 0xff))
|
||||
return 0;
|
||||
if (pkcs7[1] == 0x80)
|
||||
return 0;
|
||||
if (pkcs7[1] > 0x82)
|
||||
return -EMSGSIZE;
|
||||
}
|
||||
|
||||
pr_debug("Signature data not PKCS#7\n");
|
||||
return -ELIBBAD;
|
||||
}
|
||||
|
||||
/*
|
||||
* Compare two sections for canonicalisation.
|
||||
*/
|
||||
static int pefile_compare_shdrs(const void *a, const void *b)
|
||||
{
|
||||
const struct section_header *shdra = a;
|
||||
const struct section_header *shdrb = b;
|
||||
int rc;
|
||||
|
||||
if (shdra->data_addr > shdrb->data_addr)
|
||||
return 1;
|
||||
if (shdrb->data_addr > shdra->data_addr)
|
||||
return -1;
|
||||
|
||||
if (shdra->virtual_address > shdrb->virtual_address)
|
||||
return 1;
|
||||
if (shdrb->virtual_address > shdra->virtual_address)
|
||||
return -1;
|
||||
|
||||
rc = strcmp(shdra->name, shdrb->name);
|
||||
if (rc != 0)
|
||||
return rc;
|
||||
|
||||
if (shdra->virtual_size > shdrb->virtual_size)
|
||||
return 1;
|
||||
if (shdrb->virtual_size > shdra->virtual_size)
|
||||
return -1;
|
||||
|
||||
if (shdra->raw_data_size > shdrb->raw_data_size)
|
||||
return 1;
|
||||
if (shdrb->raw_data_size > shdra->raw_data_size)
|
||||
return -1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Load the contents of the PE binary into the digest, leaving out the image
|
||||
* checksum and the certificate data block.
|
||||
*/
|
||||
static int pefile_digest_pe_contents(const void *pebuf, unsigned int pelen,
|
||||
struct pefile_context *ctx,
|
||||
struct shash_desc *desc)
|
||||
{
|
||||
unsigned *canon, tmp, loop, i, hashed_bytes;
|
||||
int ret;
|
||||
|
||||
/* Digest the header and data directory, but leave out the image
|
||||
* checksum and the data dirent for the signature.
|
||||
*/
|
||||
ret = crypto_shash_update(desc, pebuf, ctx->image_checksum_offset);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
tmp = ctx->image_checksum_offset + sizeof(uint32_t);
|
||||
ret = crypto_shash_update(desc, pebuf + tmp,
|
||||
ctx->cert_dirent_offset - tmp);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
tmp = ctx->cert_dirent_offset + sizeof(struct data_dirent);
|
||||
ret = crypto_shash_update(desc, pebuf + tmp, ctx->header_size - tmp);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
canon = kcalloc(ctx->n_sections, sizeof(unsigned), GFP_KERNEL);
|
||||
if (!canon)
|
||||
return -ENOMEM;
|
||||
|
||||
/* We have to canonicalise the section table, so we perform an
|
||||
* insertion sort.
|
||||
*/
|
||||
canon[0] = 0;
|
||||
for (loop = 1; loop < ctx->n_sections; loop++) {
|
||||
for (i = 0; i < loop; i++) {
|
||||
if (pefile_compare_shdrs(&ctx->secs[canon[i]],
|
||||
&ctx->secs[loop]) > 0) {
|
||||
memmove(&canon[i + 1], &canon[i],
|
||||
(loop - i) * sizeof(canon[0]));
|
||||
break;
|
||||
}
|
||||
}
|
||||
canon[i] = loop;
|
||||
}
|
||||
|
||||
hashed_bytes = ctx->header_size;
|
||||
for (loop = 0; loop < ctx->n_sections; loop++) {
|
||||
i = canon[loop];
|
||||
if (ctx->secs[i].raw_data_size == 0)
|
||||
continue;
|
||||
ret = crypto_shash_update(desc,
|
||||
pebuf + ctx->secs[i].data_addr,
|
||||
ctx->secs[i].raw_data_size);
|
||||
if (ret < 0) {
|
||||
kfree(canon);
|
||||
return ret;
|
||||
}
|
||||
hashed_bytes += ctx->secs[i].raw_data_size;
|
||||
}
|
||||
kfree(canon);
|
||||
|
||||
if (pelen > hashed_bytes) {
|
||||
tmp = hashed_bytes + ctx->certs_size;
|
||||
ret = crypto_shash_update(desc,
|
||||
pebuf + hashed_bytes,
|
||||
pelen - tmp);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Digest the contents of the PE binary, leaving out the image checksum and the
|
||||
* certificate data block.
|
||||
*/
|
||||
static int pefile_digest_pe(const void *pebuf, unsigned int pelen,
|
||||
struct pefile_context *ctx)
|
||||
{
|
||||
struct crypto_shash *tfm;
|
||||
struct shash_desc *desc;
|
||||
size_t digest_size, desc_size;
|
||||
void *digest;
|
||||
int ret;
|
||||
|
||||
kenter(",%u", ctx->digest_algo);
|
||||
|
||||
/* Allocate the hashing algorithm we're going to need and find out how
|
||||
* big the hash operational data will be.
|
||||
*/
|
||||
tfm = crypto_alloc_shash(hash_algo_name[ctx->digest_algo], 0, 0);
|
||||
if (IS_ERR(tfm))
|
||||
return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm);
|
||||
|
||||
desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
|
||||
digest_size = crypto_shash_digestsize(tfm);
|
||||
|
||||
if (digest_size != ctx->digest_len) {
|
||||
pr_debug("Digest size mismatch (%zx != %x)\n",
|
||||
digest_size, ctx->digest_len);
|
||||
ret = -EBADMSG;
|
||||
goto error_no_desc;
|
||||
}
|
||||
pr_debug("Digest: desc=%zu size=%zu\n", desc_size, digest_size);
|
||||
|
||||
ret = -ENOMEM;
|
||||
desc = kzalloc(desc_size + digest_size, GFP_KERNEL);
|
||||
if (!desc)
|
||||
goto error_no_desc;
|
||||
|
||||
desc->tfm = tfm;
|
||||
desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
|
||||
ret = crypto_shash_init(desc);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
ret = pefile_digest_pe_contents(pebuf, pelen, ctx, desc);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
digest = (void *)desc + desc_size;
|
||||
ret = crypto_shash_final(desc, digest);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
pr_debug("Digest calc = [%*ph]\n", ctx->digest_len, digest);
|
||||
|
||||
/* Check that the PE file digest matches that in the MSCODE part of the
|
||||
* PKCS#7 certificate.
|
||||
*/
|
||||
if (memcmp(digest, ctx->digest, ctx->digest_len) != 0) {
|
||||
pr_debug("Digest mismatch\n");
|
||||
ret = -EKEYREJECTED;
|
||||
} else {
|
||||
pr_debug("The digests match!\n");
|
||||
}
|
||||
|
||||
error:
|
||||
kfree(desc);
|
||||
error_no_desc:
|
||||
crypto_free_shash(tfm);
|
||||
kleave(" = %d", ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* verify_pefile_signature - Verify the signature on a PE binary image
|
||||
* @pebuf: Buffer containing the PE binary image
|
||||
* @pelen: Length of the binary image
|
||||
* @trust_keyring: Signing certificates to use as starting points
|
||||
* @_trusted: Set to true if trustworth, false otherwise
|
||||
*
|
||||
* Validate that the certificate chain inside the PKCS#7 message inside the PE
|
||||
* binary image intersects keys we already know and trust.
|
||||
*
|
||||
* Returns, in order of descending priority:
|
||||
*
|
||||
* (*) -ELIBBAD if the image cannot be parsed, or:
|
||||
*
|
||||
* (*) -EKEYREJECTED if a signature failed to match for which we have a valid
|
||||
* key, or:
|
||||
*
|
||||
* (*) 0 if at least one signature chain intersects with the keys in the trust
|
||||
* keyring, or:
|
||||
*
|
||||
* (*) -ENOPKG if a suitable crypto module couldn't be found for a check on a
|
||||
* chain.
|
||||
*
|
||||
* (*) -ENOKEY if we couldn't find a match for any of the signature chains in
|
||||
* the message.
|
||||
*
|
||||
* May also return -ENOMEM.
|
||||
*/
|
||||
int verify_pefile_signature(const void *pebuf, unsigned pelen,
|
||||
struct key *trusted_keyring, bool *_trusted)
|
||||
{
|
||||
struct pkcs7_message *pkcs7;
|
||||
struct pefile_context ctx;
|
||||
const void *data;
|
||||
size_t datalen;
|
||||
int ret;
|
||||
|
||||
kenter("");
|
||||
|
||||
memset(&ctx, 0, sizeof(ctx));
|
||||
ret = pefile_parse_binary(pebuf, pelen, &ctx);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
ret = pefile_strip_sig_wrapper(pebuf, &ctx);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
pkcs7 = pkcs7_parse_message(pebuf + ctx.sig_offset, ctx.sig_len);
|
||||
if (IS_ERR(pkcs7))
|
||||
return PTR_ERR(pkcs7);
|
||||
ctx.pkcs7 = pkcs7;
|
||||
|
||||
ret = pkcs7_get_content_data(ctx.pkcs7, &data, &datalen, false);
|
||||
if (ret < 0 || datalen == 0) {
|
||||
pr_devel("PKCS#7 message does not contain data\n");
|
||||
ret = -EBADMSG;
|
||||
goto error;
|
||||
}
|
||||
|
||||
ret = mscode_parse(&ctx);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
pr_debug("Digest: %u [%*ph]\n",
|
||||
ctx.digest_len, ctx.digest_len, ctx.digest);
|
||||
|
||||
/* Generate the digest and check against the PKCS7 certificate
|
||||
* contents.
|
||||
*/
|
||||
ret = pefile_digest_pe(pebuf, pelen, &ctx);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
ret = pkcs7_verify(pkcs7);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
ret = pkcs7_validate_trust(pkcs7, trusted_keyring, _trusted);
|
||||
|
||||
error:
|
||||
pkcs7_free_message(ctx.pkcs7);
|
||||
return ret;
|
||||
}
|
@@ -0,0 +1,42 @@
|
||||
/* PE Binary parser bits
|
||||
*
|
||||
* Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
|
||||
* Written by David Howells (dhowells@redhat.com)
|
||||
*
|
||||
* 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.
|
||||
*/
|
||||
|
||||
#include <linux/verify_pefile.h>
|
||||
#include <crypto/pkcs7.h>
|
||||
#include <crypto/hash_info.h>
|
||||
|
||||
struct pefile_context {
|
||||
unsigned header_size;
|
||||
unsigned image_checksum_offset;
|
||||
unsigned cert_dirent_offset;
|
||||
unsigned n_data_dirents;
|
||||
unsigned n_sections;
|
||||
unsigned certs_size;
|
||||
unsigned sig_offset;
|
||||
unsigned sig_len;
|
||||
const struct section_header *secs;
|
||||
struct pkcs7_message *pkcs7;
|
||||
|
||||
/* PKCS#7 MS Individual Code Signing content */
|
||||
const void *digest; /* Digest */
|
||||
unsigned digest_len; /* Digest length */
|
||||
enum hash_algo digest_algo; /* Digest algorithm */
|
||||
};
|
||||
|
||||
#define kenter(FMT, ...) \
|
||||
pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__)
|
||||
#define kleave(FMT, ...) \
|
||||
pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
|
||||
|
||||
/*
|
||||
* mscode_parser.c
|
||||
*/
|
||||
extern int mscode_parse(struct pefile_context *ctx);
|
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