[U-Boot] [PATCH v1 10/11] lib: crypto: add pkcs7 message parser

AKASHI Takahiro
2019-10-11T07:41:59Z

Imported from linux kernel v5.3.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
include/crypto/pkcs7.h | 47 +++
lib/crypto/Kconfig | 9 +
lib/crypto/Makefile | 11 +
lib/crypto/pkcs7.asn1 | 135 ++++++++
lib/crypto/pkcs7_parser.c | 693 ++++++++++++++++++++++++++++++++++++++
lib/crypto/pkcs7_parser.h | 65 ++++
scripts/Makefile.build | 4 +-
7 files changed, 961 insertions(+), 3 deletions(-)
create mode 100644 include/crypto/pkcs7.h
create mode 100644 lib/crypto/pkcs7.asn1
create mode 100644 lib/crypto/pkcs7_parser.c
create mode 100644 lib/crypto/pkcs7_parser.h

diff --git a/include/crypto/pkcs7.h b/include/crypto/pkcs7.h
new file mode 100644
index 000000000000..8f5c8a7ee3b9
--- /dev/null
+++ b/include/crypto/pkcs7.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* PKCS#7 crypto data parser
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells at redhat.com)
+ */
+
+#ifndef _CRYPTO_PKCS7_H
+#define _CRYPTO_PKCS7_H
+
+#ifndef __UBOOT__
+#include <linux/verification.h>
+#include <crypto/public_key.h>
+#endif
+
+struct key;
+struct pkcs7_message;
+
+/*
+ * pkcs7_parser.c
+ */
+extern struct pkcs7_message *pkcs7_parse_message(const void *data,
+ size_t datalen);
+extern void pkcs7_free_message(struct pkcs7_message *pkcs7);
+
+extern int pkcs7_get_content_data(const struct pkcs7_message *pkcs7,
+ const void **_data, size_t *_datalen,
+ size_t *_headerlen);
+
+#ifndef __UBOOT__
+/*
+ * pkcs7_trust.c
+ */
+extern int pkcs7_validate_trust(struct pkcs7_message *pkcs7,
+ struct key *trust_keyring);
+
+/*
+ * pkcs7_verify.c
+ */
+extern int pkcs7_verify(struct pkcs7_message *pkcs7,
+ enum key_being_used_for usage);
+
+extern int pkcs7_supply_detached_data(struct pkcs7_message *pkcs7,
+ const void *data, size_t datalen);
+#endif
+
+#endif /* _CRYPTO_PKCS7_H */
diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig
index a87cf6107fc1..86b676515405 100644
--- a/lib/crypto/Kconfig
+++ b/lib/crypto/Kconfig
@@ -26,4 +26,13 @@ config X509_CERTIFICATE_PARSER
data and provides the ability to instantiate a crypto key from a
public key packet found inside the certificate.

+config PKCS7_MESSAGE_PARSER
+ bool "PKCS#7 message parser"
+ depends on X509_CERTIFICATE_PARSER
+ select ASN1
+ select OID_REGISTRY
+ help
+ This option provides support for parsing PKCS#7 format messages for
+ signature data and provides the ability to verify the signature.
+
endif # ASYMMETRIC_KEY_TYPE
diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile
index 2ec2d81a1f3c..a02ad51e698c 100644
--- a/lib/crypto/Makefile
+++ b/lib/crypto/Makefile
@@ -25,3 +25,14 @@ $(obj)/x509_cert_parser.o: \

$(obj)/x509.asn1.o: $(obj)/x509.asn1.c $(obj)/x509.asn1.h
$(obj)/x509_akid.asn1.o: $(obj)/x509_akid.asn1.c $(obj)/x509_akid.asn1.h
+
+#
+# PKCS#7 message handling
+#
+obj-$(CONFIG_PKCS7_MESSAGE_PARSER) += pkcs7_message.o
+pkcs7_message-y := \
+ pkcs7.asn1.o \
+ pkcs7_parser.o
+
+$(obj)/pkcs7_parser.o: $(obj)/pkcs7.asn1.h
+$(obj)/pkcs7.asn1.o: $(obj)/pkcs7.asn1.c $(obj)/pkcs7.asn1.h
diff --git a/lib/crypto/pkcs7.asn1 b/lib/crypto/pkcs7.asn1
new file mode 100644
index 000000000000..1eca740b816a
--- /dev/null
+++ b/lib/crypto/pkcs7.asn1
@@ -0,0 +1,135 @@
+PKCS7ContentInfo ::= SEQUENCE {
+ contentType ContentType ({ pkcs7_check_content_type }),
+ content [0] EXPLICIT SignedData OPTIONAL
+}
+
+ContentType ::= OBJECT IDENTIFIER ({ pkcs7_note_OID })
+
+SignedData ::= SEQUENCE {
+ version INTEGER ({ pkcs7_note_signeddata_version }),
+ digestAlgorithms DigestAlgorithmIdentifiers,
+ contentInfo ContentInfo ({ pkcs7_note_content }),
+ certificates CHOICE {
+ certSet [0] IMPLICIT ExtendedCertificatesAndCertificates,
+ certSequence [2] IMPLICIT Certificates
+ } OPTIONAL ({ pkcs7_note_certificate_list }),
+ crls CHOICE {
+ crlSet [1] IMPLICIT CertificateRevocationLists,
+ crlSequence [3] IMPLICIT CRLSequence
+ } OPTIONAL,
+ signerInfos SignerInfos
+}
+
+ContentInfo ::= SEQUENCE {
+ contentType ContentType ({ pkcs7_note_OID }),
+ content [0] EXPLICIT Data OPTIONAL
+}
+
+Data ::= ANY ({ pkcs7_note_data })
+
+DigestAlgorithmIdentifiers ::= CHOICE {
+ daSet SET OF DigestAlgorithmIdentifier,
+ daSequence SEQUENCE OF DigestAlgorithmIdentifier
+}
+
+DigestAlgorithmIdentifier ::= SEQUENCE {
+ algorithm OBJECT IDENTIFIER ({ pkcs7_note_OID }),
+ parameters ANY OPTIONAL
+}
+
+--
+-- Certificates and certificate lists
+--
+ExtendedCertificatesAndCertificates ::= SET OF ExtendedCertificateOrCertificate
+
+ExtendedCertificateOrCertificate ::= CHOICE {
+ certificate Certificate, -- X.509
+ extendedCertificate [0] IMPLICIT ExtendedCertificate -- PKCS#6
+}
+
+ExtendedCertificate ::= Certificate -- cheating
+
+Certificates ::= SEQUENCE OF Certificate
+
+CertificateRevocationLists ::= SET OF CertificateList
+
+CertificateList ::= SEQUENCE OF Certificate -- This may be defined incorrectly
+
+CRLSequence ::= SEQUENCE OF CertificateList
+
+Certificate ::= ANY ({ pkcs7_extract_cert }) -- X.509
+
+--
+-- Signer information
+--
+SignerInfos ::= CHOICE {
+ siSet SET OF SignerInfo,
+ siSequence SEQUENCE OF SignerInfo
+}
+
+SignerInfo ::= SEQUENCE {
+ version INTEGER ({ pkcs7_note_signerinfo_version }),
+ sid SignerIdentifier, -- CMS variant, not PKCS#7
+ digestAlgorithm DigestAlgorithmIdentifier ({ pkcs7_sig_note_digest_algo }),
+ authenticatedAttributes CHOICE {
+ aaSet [0] IMPLICIT SetOfAuthenticatedAttribute
+ ({ pkcs7_sig_note_set_of_authattrs }),
+ aaSequence [2] EXPLICIT SEQUENCE OF AuthenticatedAttribute
+ -- Explicit because easier to compute digest on
+ -- sequence of attributes and then reuse encoded
+ -- sequence in aaSequence.
+ } OPTIONAL,
+ digestEncryptionAlgorithm
+ DigestEncryptionAlgorithmIdentifier ({ pkcs7_sig_note_pkey_algo }),
+ encryptedDigest EncryptedDigest,
+ unauthenticatedAttributes CHOICE {
+ uaSet [1] IMPLICIT SET OF UnauthenticatedAttribute,
+ uaSequence [3] IMPLICIT SEQUENCE OF UnauthenticatedAttribute
+ } OPTIONAL
+} ({ pkcs7_note_signed_info })
+
+SignerIdentifier ::= CHOICE {
+ -- RFC5652 sec 5.3
+ issuerAndSerialNumber IssuerAndSerialNumber,
+ subjectKeyIdentifier [0] IMPLICIT SubjectKeyIdentifier
+}
+
+IssuerAndSerialNumber ::= SEQUENCE {
+ issuer Name ({ pkcs7_sig_note_issuer }),
+ serialNumber CertificateSerialNumber ({ pkcs7_sig_note_serial })
+}
+
+CertificateSerialNumber ::= INTEGER
+
+SubjectKeyIdentifier ::= OCTET STRING ({ pkcs7_sig_note_skid })
+
+SetOfAuthenticatedAttribute ::= SET OF AuthenticatedAttribute
+
+AuthenticatedAttribute ::= SEQUENCE {
+ type OBJECT IDENTIFIER ({ pkcs7_note_OID }),
+ values SET OF ANY ({ pkcs7_sig_note_authenticated_attr })
+}
+
+UnauthenticatedAttribute ::= SEQUENCE {
+ type OBJECT IDENTIFIER,
+ values SET OF ANY
+}
+
+DigestEncryptionAlgorithmIdentifier ::= SEQUENCE {
+ algorithm OBJECT IDENTIFIER ({ pkcs7_note_OID }),
+ parameters ANY OPTIONAL
+}
+
+EncryptedDigest ::= OCTET STRING ({ pkcs7_sig_note_signature })
+
+---
+--- X.500 Name
+---
+Name ::= SEQUENCE OF RelativeDistinguishedName
+
+RelativeDistinguishedName ::= SET OF AttributeValueAssertion
+
+AttributeValueAssertion ::= SEQUENCE {
+ attributeType OBJECT IDENTIFIER ({ pkcs7_note_OID }),
+ attributeValue ANY
+}
diff --git a/lib/crypto/pkcs7_parser.c b/lib/crypto/pkcs7_parser.c
new file mode 100644
index 000000000000..bf9e7e888f6b
--- /dev/null
+++ b/lib/crypto/pkcs7_parser.c
@@ -0,0 +1,693 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* PKCS#7 parser
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells at redhat.com)
+ */
+
+#define pr_fmt(fmt) "PKCS7: "fmt
+#ifdef __UBOOT__
+#include <linux/bitops.h>
+#include <linux/compat.h>
+#endif
+#include <linux/kernel.h>
+#ifndef __UBOOT__
+#include <linux/module.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#endif
+#include <linux/err.h>
+#include <linux/oid_registry.h>
+#include <crypto/public_key.h>
+#include "pkcs7_parser.h"
+#include "pkcs7.asn1.h"
+
+MODULE_DESCRIPTION("PKCS#7 parser");
+MODULE_AUTHOR("Red Hat, Inc.");
+MODULE_LICENSE("GPL");
+
+struct pkcs7_parse_context {
+ struct pkcs7_message *msg; /* Message being constructed */
+ struct pkcs7_signed_info *sinfo; /* SignedInfo being constructed */
+ struct pkcs7_signed_info **ppsinfo;
+ struct x509_certificate *certs; /* Certificate cache */
+ struct x509_certificate **ppcerts;
+ unsigned long data; /* Start of data */
+ enum OID last_oid; /* Last OID encountered */
+ unsigned x509_index;
+ unsigned sinfo_index;
+ const void *raw_serial;
+ unsigned raw_serial_size;
+ unsigned raw_issuer_size;
+ const void *raw_issuer;
+ const void *raw_skid;
+ unsigned raw_skid_size;
+ bool expect_skid;
+};
+
+/*
+ * Free a signed information block.
+ */
+static void pkcs7_free_signed_info(struct pkcs7_signed_info *sinfo)
+{
+ if (sinfo) {
+ public_key_signature_free(sinfo->sig);
+ kfree(sinfo);
+ }
+}
+
+/**
+ * pkcs7_free_message - Free a PKCS#7 message
+ * @pkcs7: The PKCS#7 message to free
+ */
+void pkcs7_free_message(struct pkcs7_message *pkcs7)
+{
+ struct x509_certificate *cert;
+ struct pkcs7_signed_info *sinfo;
+
+ if (pkcs7) {
+ while (pkcs7->certs) {
+ cert = pkcs7->certs;
+ pkcs7->certs = cert->next;
+ x509_free_certificate(cert);
+ }
+ while (pkcs7->crl) {
+ cert = pkcs7->crl;
+ pkcs7->crl = cert->next;
+ x509_free_certificate(cert);
+ }
+ while (pkcs7->signed_infos) {
+ sinfo = pkcs7->signed_infos;
+ pkcs7->signed_infos = sinfo->next;
+ pkcs7_free_signed_info(sinfo);
+ }
+ kfree(pkcs7);
+ }
+}
+EXPORT_SYMBOL_GPL(pkcs7_free_message);
+
+/*
+ * Check authenticatedAttributes are provided or not provided consistently.
+ */
+static int pkcs7_check_authattrs(struct pkcs7_message *msg)
+{
+ struct pkcs7_signed_info *sinfo;
+ bool want = false;
+
+ sinfo = msg->signed_infos;
+ if (!sinfo)
+ goto inconsistent;
+
+ if (sinfo->authattrs) {
+ want = true;
+ msg->have_authattrs = true;
+ }
+
+ for (sinfo = sinfo->next; sinfo; sinfo = sinfo->next)
+ if (!!sinfo->authattrs != want)
+ goto inconsistent;
+ return 0;
+
+inconsistent:
+ pr_warn("Inconsistently supplied authAttrs\n");
+ return -EINVAL;
+}
+
+/**
+ * pkcs7_parse_message - Parse a PKCS#7 message
+ * @data: The raw binary ASN.1 encoded message to be parsed
+ * @datalen: The size of the encoded message
+ */
+struct pkcs7_message *pkcs7_parse_message(const void *data, size_t datalen)
+{
+ struct pkcs7_parse_context *ctx;
+ struct pkcs7_message *msg = ERR_PTR(-ENOMEM);
+ int ret;
+
+ ctx = kzalloc(sizeof(struct pkcs7_parse_context), GFP_KERNEL);
+ if (!ctx)
+ goto out_no_ctx;
+ ctx->msg = kzalloc(sizeof(struct pkcs7_message), GFP_KERNEL);
+ if (!ctx->msg)
+ goto out_no_msg;
+ ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
+ if (!ctx->sinfo)
+ goto out_no_sinfo;
+ ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
+ GFP_KERNEL);
+ if (!ctx->sinfo->sig)
+ goto out_no_sig;
+
+ ctx->data = (unsigned long)data;
+ ctx->ppcerts = &ctx->certs;
+ ctx->ppsinfo = &ctx->msg->signed_infos;
+
+ /* Attempt to decode the signature */
+ ret = asn1_ber_decoder(&pkcs7_decoder, ctx, data, datalen);
+ if (ret < 0) {
+ msg = ERR_PTR(ret);
+ goto out;
+ }
+
+ ret = pkcs7_check_authattrs(ctx->msg);
+ if (ret < 0) {
+ msg = ERR_PTR(ret);
+ goto out;
+ }
+
+ msg = ctx->msg;
+ ctx->msg = NULL;
+
+out:
+ while (ctx->certs) {
+ struct x509_certificate *cert = ctx->certs;
+ ctx->certs = cert->next;
+ x509_free_certificate(cert);
+ }
+out_no_sig:
+ pkcs7_free_signed_info(ctx->sinfo);
+out_no_sinfo:
+ pkcs7_free_message(ctx->msg);
+out_no_msg:
+ kfree(ctx);
+out_no_ctx:
+ return msg;
+}
+EXPORT_SYMBOL_GPL(pkcs7_parse_message);
+
+/**
+ * pkcs7_get_content_data - Get access to the PKCS#7 content
+ * @pkcs7: The preparsed PKCS#7 message to access
+ * @_data: Place to return a pointer to the data
+ * @_data_len: Place to return the data length
+ * @_headerlen: Size of ASN.1 header not included in _data
+ *
+ * Get access to the data content of the PKCS#7 message. The size of the
+ * header of the ASN.1 object that contains it is also provided and can be used
+ * to adjust *_data and *_data_len to get the entire object.
+ *
+ * Returns -ENODATA if the data object was missing from the message.
+ */
+int pkcs7_get_content_data(const struct pkcs7_message *pkcs7,
+ const void **_data, size_t *_data_len,
+ size_t *_headerlen)
+{
+ if (!pkcs7->data)
+ return -ENODATA;
+
+ *_data = pkcs7->data;
+ *_data_len = pkcs7->data_len;
+ if (_headerlen)
+ *_headerlen = pkcs7->data_hdrlen;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pkcs7_get_content_data);
+
+/*
+ * Note an OID when we find one for later processing when we know how
+ * to interpret it.
+ */
+int pkcs7_note_OID(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ ctx->last_oid = look_up_OID(value, vlen);
+ if (ctx->last_oid == OID__NR) {
+ char buffer[50];
+ sprint_oid(value, vlen, buffer, sizeof(buffer));
+ printk("PKCS7: Unknown OID: [%lu] %s\n",
+ (unsigned long)value - ctx->data, buffer);
+ }
+ return 0;
+}
+
+/*
+ * Note the digest algorithm for the signature.
+ */
+int pkcs7_sig_note_digest_algo(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ switch (ctx->last_oid) {
+ case OID_md4:
+ ctx->sinfo->sig->hash_algo = "md4";
+ break;
+ case OID_md5:
+ ctx->sinfo->sig->hash_algo = "md5";
+ break;
+ case OID_sha1:
+ ctx->sinfo->sig->hash_algo = "sha1";
+ break;
+ case OID_sha256:
+ ctx->sinfo->sig->hash_algo = "sha256";
+ break;
+ case OID_sha384:
+ ctx->sinfo->sig->hash_algo = "sha384";
+ break;
+ case OID_sha512:
+ ctx->sinfo->sig->hash_algo = "sha512";
+ break;
+ case OID_sha224:
+ ctx->sinfo->sig->hash_algo = "sha224";
+ break;
+ default:
+ printk("Unsupported digest algo: %u\n", ctx->last_oid);
+ return -ENOPKG;
+ }
+ return 0;
+}
+
+/*
+ * Note the public key algorithm for the signature.
+ */
+int pkcs7_sig_note_pkey_algo(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ switch (ctx->last_oid) {
+ case OID_rsaEncryption:
+ ctx->sinfo->sig->pkey_algo = "rsa";
+ ctx->sinfo->sig->encoding = "pkcs1";
+ break;
+ default:
+ printk("Unsupported pkey algo: %u\n", ctx->last_oid);
+ return -ENOPKG;
+ }
+ return 0;
+}
+
+/*
+ * We only support signed data [RFC2315 sec 9].
+ */
+int pkcs7_check_content_type(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ if (ctx->last_oid != OID_signed_data) {
+ pr_warn("Only support pkcs7_signedData type\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * Note the SignedData version
+ */
+int pkcs7_note_signeddata_version(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ unsigned version;
+
+ if (vlen != 1)
+ goto unsupported;
+
+ ctx->msg->version = version = *(const u8 *)value;
+ switch (version) {
+ case 1:
+ /* PKCS#7 SignedData [RFC2315 sec 9.1]
+ * CMS ver 1 SignedData [RFC5652 sec 5.1]
+ */
+ break;
+ case 3:
+ /* CMS ver 3 SignedData [RFC2315 sec 5.1] */
+ break;
+ default:
+ goto unsupported;
+ }
+
+ return 0;
+
+unsupported:
+ pr_warn("Unsupported SignedData version\n");
+ return -EINVAL;
+}
+
+/*
+ * Note the SignerInfo version
+ */
+int pkcs7_note_signerinfo_version(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ unsigned version;
+
+ if (vlen != 1)
+ goto unsupported;
+
+ version = *(const u8 *)value;
+ switch (version) {
+ case 1:
+ /* PKCS#7 SignerInfo [RFC2315 sec 9.2]
+ * CMS ver 1 SignerInfo [RFC5652 sec 5.3]
+ */
+ if (ctx->msg->version != 1)
+ goto version_mismatch;
+ ctx->expect_skid = false;
+ break;
+ case 3:
+ /* CMS ver 3 SignerInfo [RFC2315 sec 5.3] */
+ if (ctx->msg->version == 1)
+ goto version_mismatch;
+ ctx->expect_skid = true;
+ break;
+ default:
+ goto unsupported;
+ }
+
+ return 0;
+
+unsupported:
+ pr_warn("Unsupported SignerInfo version\n");
+ return -EINVAL;
+version_mismatch:
+ pr_warn("SignedData-SignerInfo version mismatch\n");
+ return -EBADMSG;
+}
+
+/*
+ * Extract a certificate and store it in the context.
+ */
+int pkcs7_extract_cert(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ struct x509_certificate *x509;
+
+ if (tag != ((ASN1_UNIV << 6) | ASN1_CONS_BIT | ASN1_SEQ)) {
+ pr_debug("Cert began with tag %02x@%lu\n",
+ tag, (unsigned long)ctx - ctx->data);
+ return -EBADMSG;
+ }
+
+ /* We have to correct for the header so that the X.509 parser can start
+ * from the beginning. Note that since X.509 stipulates DER, there
+ * probably shouldn't be an EOC trailer - but it is in PKCS#7 (which
+ * stipulates BER).
+ */
+ value -= hdrlen;
+ vlen += hdrlen;
+
+ if (((u8*)value)[1] == 0x80)
+ vlen += 2; /* Indefinite length - there should be an EOC */
+
+ x509 = x509_cert_parse(value, vlen);
+ if (IS_ERR(x509))
+ return PTR_ERR(x509);
+
+ x509->index = ++ctx->x509_index;
+ pr_debug("Got cert %u for %s\n", x509->index, x509->subject);
+ pr_debug("- fingerprint %*phN\n", x509->id->len, x509->id->data);
+
+ *ctx->ppcerts = x509;
+ ctx->ppcerts = &x509->next;
+ return 0;
+}
+
+/*
+ * Save the certificate list
+ */
+int pkcs7_note_certificate_list(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ pr_devel("Got cert list (%02x)\n", tag);
+
+ *ctx->ppcerts = ctx->msg->certs;
+ ctx->msg->certs = ctx->certs;
+ ctx->certs = NULL;
+ ctx->ppcerts = &ctx->certs;
+ return 0;
+}
+
+/*
+ * Note the content type.
+ */
+int pkcs7_note_content(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ if (ctx->last_oid != OID_data &&
+ ctx->last_oid != OID_msIndirectData) {
+ pr_warn("Unsupported data type %d\n", ctx->last_oid);
+ return -EINVAL;
+ }
+
+ ctx->msg->data_type = ctx->last_oid;
+ return 0;
+}
+
+/*
+ * Extract the data from the message and store that and its content type OID in
+ * the context.
+ */
+int pkcs7_note_data(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ pr_debug("Got data\n");
+
+ ctx->msg->data = value;
+ ctx->msg->data_len = vlen;
+ ctx->msg->data_hdrlen = hdrlen;
+ return 0;
+}
+
+/*
+ * Parse authenticated attributes.
+ */
+int pkcs7_sig_note_authenticated_attr(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ struct pkcs7_signed_info *sinfo = ctx->sinfo;
+ enum OID content_type;
+
+ pr_devel("AuthAttr: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
+
+ switch (ctx->last_oid) {
+ case OID_contentType:
+ if (__test_and_set_bit(sinfo_has_content_type, &sinfo->aa_set))
+ goto repeated;
+ content_type = look_up_OID(value, vlen);
+ if (content_type != ctx->msg->data_type) {
+ pr_warn("Mismatch between global data type (%d) and sinfo %u (%d)\n",
+ ctx->msg->data_type, sinfo->index,
+ content_type);
+ return -EBADMSG;
+ }
+ return 0;
+
+ case OID_signingTime:
+ if (__test_and_set_bit(sinfo_has_signing_time, &sinfo->aa_set))
+ goto repeated;
+ /* Should we check that the signing time is consistent
+ * with the signer's X.509 cert?
+ */
+ return x509_decode_time(&sinfo->signing_time,
+ hdrlen, tag, value, vlen);
+
+ case OID_messageDigest:
+ if (__test_and_set_bit(sinfo_has_message_digest, &sinfo->aa_set))
+ goto repeated;
+ if (tag != ASN1_OTS)
+ return -EBADMSG;
+ sinfo->msgdigest = value;
+ sinfo->msgdigest_len = vlen;
+ return 0;
+
+ case OID_smimeCapabilites:
+ if (__test_and_set_bit(sinfo_has_smime_caps, &sinfo->aa_set))
+ goto repeated;
+#ifdef __UBOOT__ /* OID_data is needed for authenticated UEFI variables */
+ if (ctx->msg->data_type != OID_msIndirectData &&
+ ctx->msg->data_type != OID_data) {
+#else
+ if (ctx->msg->data_type != OID_msIndirectData) {
+#endif
+ pr_warn("S/MIME Caps only allowed with Authenticode\n");
+ return -EKEYREJECTED;
+ }
+ return 0;
+
+ /* Microsoft SpOpusInfo seems to be contain cont[0] 16-bit BE
+ * char URLs and cont[1] 8-bit char URLs.
+ *
+ * Microsoft StatementType seems to contain a list of OIDs that
+ * are also used as extendedKeyUsage types in X.509 certs.
+ */
+ case OID_msSpOpusInfo:
+ if (__test_and_set_bit(sinfo_has_ms_opus_info, &sinfo->aa_set))
+ goto repeated;
+ goto authenticode_check;
+ case OID_msStatementType:
+ if (__test_and_set_bit(sinfo_has_ms_statement_type, &sinfo->aa_set))
+ goto repeated;
+ authenticode_check:
+ if (ctx->msg->data_type != OID_msIndirectData) {
+ pr_warn("Authenticode AuthAttrs only allowed with Authenticode\n");
+ return -EKEYREJECTED;
+ }
+ /* I'm not sure how to validate these */
+ return 0;
+ default:
+ return 0;
+ }
+
+repeated:
+ /* We permit max one item per AuthenticatedAttribute and no repeats */
+ pr_warn("Repeated/multivalue AuthAttrs not permitted\n");
+ return -EKEYREJECTED;
+}
+
+/*
+ * Note the set of auth attributes for digestion purposes [RFC2315 sec 9.3]
+ */
+int pkcs7_sig_note_set_of_authattrs(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ struct pkcs7_signed_info *sinfo = ctx->sinfo;
+
+ if (!test_bit(sinfo_has_content_type, &sinfo->aa_set) ||
+ !test_bit(sinfo_has_message_digest, &sinfo->aa_set)) {
+ pr_warn("Missing required AuthAttr\n");
+ return -EBADMSG;
+ }
+
+ if (ctx->msg->data_type != OID_msIndirectData &&
+ test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) {
+ pr_warn("Unexpected Authenticode AuthAttr\n");
+ return -EBADMSG;
+ }
+
+ /* We need to switch the 'CONT 0' to a 'SET OF' when we digest */
+ sinfo->authattrs = value - (hdrlen - 1);
+ sinfo->authattrs_len = vlen + (hdrlen - 1);
+ return 0;
+}
+
+/*
+ * Note the issuing certificate serial number
+ */
+int pkcs7_sig_note_serial(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ ctx->raw_serial = value;
+ ctx->raw_serial_size = vlen;
+ return 0;
+}
+
+/*
+ * Note the issuer's name
+ */
+int pkcs7_sig_note_issuer(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ ctx->raw_issuer = value;
+ ctx->raw_issuer_size = vlen;
+ return 0;
+}
+
+/*
+ * Note the issuing cert's subjectKeyIdentifier
+ */
+int pkcs7_sig_note_skid(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ pr_devel("SKID: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
+
+ ctx->raw_skid = value;
+ ctx->raw_skid_size = vlen;
+ return 0;
+}
+
+/*
+ * Note the signature data
+ */
+int pkcs7_sig_note_signature(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ ctx->sinfo->sig->s = kmemdup(value, vlen, GFP_KERNEL);
+ if (!ctx->sinfo->sig->s)
+ return -ENOMEM;
+
+ ctx->sinfo->sig->s_size = vlen;
+ return 0;
+}
+
+/*
+ * Note a signature information block
+ */
+int pkcs7_note_signed_info(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ struct pkcs7_signed_info *sinfo = ctx->sinfo;
+ struct asymmetric_key_id *kid;
+
+ if (ctx->msg->data_type == OID_msIndirectData && !sinfo->authattrs) {
+ pr_warn("Authenticode requires AuthAttrs\n");
+ return -EBADMSG;
+ }
+
+ /* Generate cert issuer + serial number key ID */
+ if (!ctx->expect_skid) {
+ kid = asymmetric_key_generate_id(ctx->raw_serial,
+ ctx->raw_serial_size,
+ ctx->raw_issuer,
+ ctx->raw_issuer_size);
+ } else {
+ kid = asymmetric_key_generate_id(ctx->raw_skid,
+ ctx->raw_skid_size,
+ "", 0);
+ }
+ if (IS_ERR(kid))
+ return PTR_ERR(kid);
+
+ pr_devel("SINFO KID: %u [%*phN]\n", kid->len, kid->len, kid->data);
+
+ sinfo->sig->auth_ids[0] = kid;
+ sinfo->index = ++ctx->sinfo_index;
+ *ctx->ppsinfo = sinfo;
+ ctx->ppsinfo = &sinfo->next;
+ ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
+ if (!ctx->sinfo)
+ return -ENOMEM;
+ ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
+ GFP_KERNEL);
+ if (!ctx->sinfo->sig)
+ return -ENOMEM;
+ return 0;
+}
diff --git a/lib/crypto/pkcs7_parser.h b/lib/crypto/pkcs7_parser.h
new file mode 100644
index 000000000000..6565fdc2d4ca
--- /dev/null
+++ b/lib/crypto/pkcs7_parser.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* PKCS#7 crypto data parser internal definitions
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells at redhat.com)
+ */
+
+#include <linux/oid_registry.h>
+#include <crypto/pkcs7.h>
+#include "x509_parser.h"
+
+#define kenter(FMT, ...) \
+ pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__)
+#define kleave(FMT, ...) \
+ pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
+
+struct pkcs7_signed_info {
+ struct pkcs7_signed_info *next;
+ struct x509_certificate *signer; /* Signing certificate (in msg->certs) */
+ unsigned index;
+ bool unsupported_crypto; /* T if not usable due to missing crypto */
+ bool blacklisted;
+
+ /* Message digest - the digest of the Content Data (or NULL) */
+ const void *msgdigest;
+ unsigned msgdigest_len;
+
+ /* Authenticated Attribute data (or NULL) */
+ unsigned authattrs_len;
+ const void *authattrs;
+ unsigned long aa_set;
+#define sinfo_has_content_type 0
+#define sinfo_has_signing_time 1
+#define sinfo_has_message_digest 2
+#define sinfo_has_smime_caps 3
+#define sinfo_has_ms_opus_info 4
+#define sinfo_has_ms_statement_type 5
+ time64_t signing_time;
+
+ /* Message signature.
+ *
+ * This contains the generated digest of _either_ the Content Data or
+ * the Authenticated Attributes [RFC2315 9.3]. If the latter, one of
+ * the attributes contains the digest of the the Content Data within
+ * it.
+ *
+ * THis also contains the issuing cert serial number and issuer's name
+ * [PKCS#7 or CMS ver 1] or issuing cert's SKID [CMS ver 3].
+ */
+ struct public_key_signature *sig;
+};
+
+struct pkcs7_message {
+ struct x509_certificate *certs; /* Certificate list */
+ struct x509_certificate *crl; /* Revocation list */
+ struct pkcs7_signed_info *signed_infos;
+ u8 version; /* Version of cert (1 -> PKCS#7 or CMS; 3 -> CMS) */
+ bool have_authattrs; /* T if have authattrs */
+
+ /* Content Data (or NULL) */
+ enum OID data_type; /* Type of Data */
+ size_t data_len; /* Length of Data */
+ size_t data_hdrlen; /* Length of Data ASN.1 header */
+ const void *data; /* Content Data (or 0) */
+};
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 9357d310e50b..71458e089cd6 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -419,11 +419,9 @@ targets += $(multi-used-y) $(multi-used-m)
intermediate_targets = $(foreach sfx, $(2), \
$(patsubst %$(strip $(1)),%$(sfx), \
$(filter %$(strip $(1)), $(targets))))
-# %.asn1.o <- %.asn1.[ch] <- %.asn1
# %.lex.o <- %.lex.c <- %.l
# %.tab.o <- %.tab.[ch] <- %.y
-targets += $(call intermediate_targets, .asn1.o, .asn1.c .asn1.h) \
- $(call intermediate_targets, .lex.o, .lex.c) \
+targets += $(call intermediate_targets, .lex.o, .lex.c) \
$(call intermediate_targets, .tab.o, .tab.c .tab.h)

# Descending
--
2.21.0