Add qemu 2.4.0

Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>

1 files changed, 709 insertions, 0 deletions

diff --git a/qemu/roms/ipxe/src/crypto/cms.c b/qemu/roms/ipxe/src/crypto/cms.c
new file mode 100644
index 000000000..b4a41de6c
--- /dev/null
+++ b/qemu/roms/ipxe/src/crypto/cms.c
@@ -0,0 +1,709 @@
+/*
+ * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/** @file
+ *
+ * Cryptographic Message Syntax (PKCS #7)
+ *
+ * The format of CMS messages is defined in RFC 5652.
+ *
+ */
+
+#include <stdint.h>
+#include <string.h>
+#include <time.h>
+#include <errno.h>
+#include <ipxe/asn1.h>
+#include <ipxe/x509.h>
+#include <ipxe/malloc.h>
+#include <ipxe/uaccess.h>
+#include <ipxe/cms.h>
+
+/* Disambiguate the various error causes */
+#define EACCES_NON_SIGNING \
+	__einfo_error ( EINFO_EACCES_NON_SIGNING )
+#define EINFO_EACCES_NON_SIGNING \
+	__einfo_uniqify ( EINFO_EACCES, 0x01, "Not a signing certificate" )
+#define EACCES_NON_CODE_SIGNING \
+	__einfo_error ( EINFO_EACCES_NON_CODE_SIGNING )
+#define EINFO_EACCES_NON_CODE_SIGNING \
+	__einfo_uniqify ( EINFO_EACCES, 0x02, "Not a code-signing certificate" )
+#define EACCES_WRONG_NAME \
+	__einfo_error ( EINFO_EACCES_WRONG_NAME )
+#define EINFO_EACCES_WRONG_NAME \
+	__einfo_uniqify ( EINFO_EACCES, 0x04, "Incorrect certificate name" )
+#define EACCES_NO_SIGNATURES \
+	__einfo_error ( EINFO_EACCES_NO_SIGNATURES )
+#define EINFO_EACCES_NO_SIGNATURES \
+	__einfo_uniqify ( EINFO_EACCES, 0x05, "No signatures present" )
+#define EINVAL_DIGEST \
+	__einfo_error ( EINFO_EINVAL_DIGEST )
+#define EINFO_EINVAL_DIGEST \
+	__einfo_uniqify ( EINFO_EINVAL, 0x01, "Not a digest algorithm" )
+#define EINVAL_PUBKEY \
+	__einfo_error ( EINFO_EINVAL_PUBKEY )
+#define EINFO_EINVAL_PUBKEY \
+	__einfo_uniqify ( EINFO_EINVAL, 0x02, "Not a public-key algorithm" )
+#define ENOTSUP_SIGNEDDATA \
+	__einfo_error ( EINFO_ENOTSUP_SIGNEDDATA )
+#define EINFO_ENOTSUP_SIGNEDDATA \
+	__einfo_uniqify ( EINFO_ENOTSUP, 0x01, "Not a digital signature" )
+
+/** "pkcs7-signedData" object identifier */
+static uint8_t oid_signeddata[] = { ASN1_OID_SIGNEDDATA };
+
+/** "pkcs7-signedData" object identifier cursor */
+static struct asn1_cursor oid_signeddata_cursor =
+	ASN1_OID_CURSOR ( oid_signeddata );
+
+/**
+ * Parse CMS signature content type
+ *
+ * @v sig		CMS signature
+ * @v raw		ASN.1 cursor
+ * @ret rc		Return status code
+ */
+static int cms_parse_content_type ( struct cms_signature *sig,
+				    const struct asn1_cursor *raw ) {
+	struct asn1_cursor cursor;
+
+	/* Enter contentType */
+	memcpy ( &cursor, raw, sizeof ( cursor ) );
+	asn1_enter ( &cursor, ASN1_OID );
+
+	/* Check OID is pkcs7-signedData */
+	if ( asn1_compare ( &cursor, &oid_signeddata_cursor ) != 0 ) {
+		DBGC ( sig, "CMS %p does not contain signedData:\n", sig );
+		DBGC_HDA ( sig, 0, raw->data, raw->len );
+		return -ENOTSUP_SIGNEDDATA;
+	}
+
+	DBGC ( sig, "CMS %p contains signedData\n", sig );
+	return 0;
+}
+
+/**
+ * Parse CMS signature certificate list
+ *
+ * @v sig		CMS signature
+ * @v raw		ASN.1 cursor
+ * @ret rc		Return status code
+ */
+static int cms_parse_certificates ( struct cms_signature *sig,
+				    const struct asn1_cursor *raw ) {
+	struct asn1_cursor cursor;
+	struct x509_certificate *cert;
+	int rc;
+
+	/* Enter certificates */
+	memcpy ( &cursor, raw, sizeof ( cursor ) );
+	asn1_enter ( &cursor, ASN1_EXPLICIT_TAG ( 0 ) );
+
+	/* Add each certificate */
+	while ( cursor.len ) {
+
+		/* Add certificate to chain */
+		if ( ( rc = x509_append_raw ( sig->certificates, cursor.data,
+					      cursor.len ) ) != 0 ) {
+			DBGC ( sig, "CMS %p could not append certificate: %s\n",
+			       sig, strerror ( rc) );
+			DBGC_HDA ( sig, 0, cursor.data, cursor.len );
+			return rc;
+		}
+		cert = x509_last ( sig->certificates );
+		DBGC ( sig, "CMS %p found certificate %s\n",
+		       sig, x509_name ( cert ) );
+
+		/* Move to next certificate */
+		asn1_skip_any ( &cursor );
+	}
+
+	return 0;
+}
+
+/**
+ * Identify CMS signature certificate by issuer and serial number
+ *
+ * @v sig		CMS signature
+ * @v issuer		Issuer
+ * @v serial		Serial number
+ * @ret cert		X.509 certificate, or NULL if not found
+ */
+static struct x509_certificate *
+cms_find_issuer_serial ( struct cms_signature *sig,
+			 const struct asn1_cursor *issuer,
+			 const struct asn1_cursor *serial ) {
+	struct x509_link *link;
+	struct x509_certificate *cert;
+
+	/* Scan through certificate list */
+	list_for_each_entry ( link, &sig->certificates->links, list ) {
+
+		/* Check issuer and serial number */
+		cert = link->cert;
+		if ( ( asn1_compare ( issuer, &cert->issuer.raw ) == 0 ) &&
+		     ( asn1_compare ( serial, &cert->serial.raw ) == 0 ) )
+			return cert;
+	}
+
+	return NULL;
+}
+
+/**
+ * Parse CMS signature signer identifier
+ *
+ * @v sig		CMS signature
+ * @v info		Signer information to fill in
+ * @v raw		ASN.1 cursor
+ * @ret rc		Return status code
+ */
+static int cms_parse_signer_identifier ( struct cms_signature *sig,
+					 struct cms_signer_info *info,
+					 const struct asn1_cursor *raw ) {
+	struct asn1_cursor cursor;
+	struct asn1_cursor serial;
+	struct asn1_cursor issuer;
+	struct x509_certificate *cert;
+	int rc;
+
+	/* Enter issuerAndSerialNumber */
+	memcpy ( &cursor, raw, sizeof ( cursor ) );
+	asn1_enter ( &cursor, ASN1_SEQUENCE );
+
+	/* Identify issuer */
+	memcpy ( &issuer, &cursor, sizeof ( issuer ) );
+	if ( ( rc = asn1_shrink ( &issuer, ASN1_SEQUENCE ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not locate issuer: %s\n",
+		       sig, info, strerror ( rc ) );
+		DBGC_HDA ( sig, 0, raw->data, raw->len );
+		return rc;
+	}
+	DBGC ( sig, "CMS %p/%p issuer is:\n", sig, info );
+	DBGC_HDA ( sig, 0, issuer.data, issuer.len );
+	asn1_skip_any ( &cursor );
+
+	/* Identify serialNumber */
+	memcpy ( &serial, &cursor, sizeof ( serial ) );
+	if ( ( rc = asn1_shrink ( &serial, ASN1_INTEGER ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not locate serialNumber: %s\n",
+		       sig, info, strerror ( rc ) );
+		DBGC_HDA ( sig, 0, raw->data, raw->len );
+		return rc;
+	}
+	DBGC ( sig, "CMS %p/%p serial number is:\n", sig, info );
+	DBGC_HDA ( sig, 0, serial.data, serial.len );
+
+	/* Identify certificate */
+	cert = cms_find_issuer_serial ( sig, &issuer, &serial );
+	if ( ! cert ) {
+		DBGC ( sig, "CMS %p/%p could not identify signer's "
+		       "certificate\n", sig, info );
+		return -ENOENT;
+	}
+
+	/* Append certificate to chain */
+	if ( ( rc = x509_append ( info->chain, cert ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not append certificate: %s\n",
+		       sig, info, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Append remaining certificates to chain */
+	if ( ( rc = x509_auto_append ( info->chain,
+				       sig->certificates ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not append certificates: %s\n",
+		       sig, info, strerror ( rc ) );
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * Parse CMS signature digest algorithm
+ *
+ * @v sig		CMS signature
+ * @v info		Signer information to fill in
+ * @v raw		ASN.1 cursor
+ * @ret rc		Return status code
+ */
+static int cms_parse_digest_algorithm ( struct cms_signature *sig,
+					struct cms_signer_info *info,
+					const struct asn1_cursor *raw ) {
+	struct asn1_algorithm *algorithm;
+	int rc;
+
+	/* Identify algorithm */
+	if ( ( rc = asn1_digest_algorithm ( raw, &algorithm ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not identify digest algorithm: "
+		       "%s\n", sig, info, strerror ( rc ) );
+		DBGC_HDA ( sig, 0, raw->data, raw->len );
+		return rc;
+	}
+
+	/* Record digest algorithm */
+	info->digest = algorithm->digest;
+	DBGC ( sig, "CMS %p/%p digest algorithm is %s\n",
+	       sig, info, algorithm->name );
+
+	return 0;
+}
+
+/**
+ * Parse CMS signature algorithm
+ *
+ * @v sig		CMS signature
+ * @v info		Signer information to fill in
+ * @v raw		ASN.1 cursor
+ * @ret rc		Return status code
+ */
+static int cms_parse_signature_algorithm ( struct cms_signature *sig,
+					   struct cms_signer_info *info,
+					   const struct asn1_cursor *raw ) {
+	struct asn1_algorithm *algorithm;
+	int rc;
+
+	/* Identify algorithm */
+	if ( ( rc = asn1_pubkey_algorithm ( raw, &algorithm ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not identify public-key "
+		       "algorithm: %s\n", sig, info, strerror ( rc ) );
+		DBGC_HDA ( sig, 0, raw->data, raw->len );
+		return rc;
+	}
+
+	/* Record signature algorithm */
+	info->pubkey = algorithm->pubkey;
+	DBGC ( sig, "CMS %p/%p public-key algorithm is %s\n",
+	       sig, info, algorithm->name );
+
+	return 0;
+}
+
+/**
+ * Parse CMS signature value
+ *
+ * @v sig		CMS signature
+ * @v info		Signer information to fill in
+ * @v raw		ASN.1 cursor
+ * @ret rc		Return status code
+ */
+static int cms_parse_signature_value ( struct cms_signature *sig,
+				       struct cms_signer_info *info,
+				       const struct asn1_cursor *raw ) {
+	struct asn1_cursor cursor;
+	int rc;
+
+	/* Enter signature */
+	memcpy ( &cursor, raw, sizeof ( cursor ) );
+	if ( ( rc = asn1_enter ( &cursor, ASN1_OCTET_STRING ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not locate signature:\n",
+		       sig, info );
+		DBGC_HDA ( sig, 0, raw->data, raw->len );
+		return rc;
+	}
+
+	/* Record signature */
+	info->signature_len = cursor.len;
+	info->signature = malloc ( info->signature_len );
+	if ( ! info->signature )
+		return -ENOMEM;
+	memcpy ( info->signature, cursor.data, info->signature_len );
+	DBGC ( sig, "CMS %p/%p signature value is:\n", sig, info );
+	DBGC_HDA ( sig, 0, info->signature, info->signature_len );
+
+	return 0;
+}
+
+/**
+ * Parse CMS signature signer information
+ *
+ * @v sig		CMS signature
+ * @v info		Signer information to fill in
+ * @v raw		ASN.1 cursor
+ * @ret rc		Return status code
+ */
+static int cms_parse_signer_info ( struct cms_signature *sig,
+				   struct cms_signer_info *info,
+				   const struct asn1_cursor *raw ) {
+	struct asn1_cursor cursor;
+	int rc;
+
+	/* Enter signerInfo */
+	memcpy ( &cursor, raw, sizeof ( cursor ) );
+	asn1_enter ( &cursor, ASN1_SEQUENCE );
+
+	/* Skip version */
+	asn1_skip ( &cursor, ASN1_INTEGER );
+
+	/* Parse sid */
+	if ( ( rc = cms_parse_signer_identifier ( sig, info, &cursor ) ) != 0 )
+		return rc;
+	asn1_skip_any ( &cursor );
+
+	/* Parse digestAlgorithm */
+	if ( ( rc = cms_parse_digest_algorithm ( sig, info, &cursor ) ) != 0 )
+		return rc;
+	asn1_skip_any ( &cursor );
+
+	/* Skip signedAttrs, if present */
+	asn1_skip_if_exists ( &cursor, ASN1_EXPLICIT_TAG ( 0 ) );
+
+	/* Parse signatureAlgorithm */
+	if ( ( rc = cms_parse_signature_algorithm ( sig, info, &cursor ) ) != 0)
+		return rc;
+	asn1_skip_any ( &cursor );
+
+	/* Parse signature */
+	if ( ( rc = cms_parse_signature_value ( sig, info, &cursor ) ) != 0 )
+		return rc;
+
+	return 0;
+}
+
+/**
+ * Parse CMS signature from ASN.1 data
+ *
+ * @v sig		CMS signature
+ * @v raw		ASN.1 cursor
+ * @ret rc		Return status code
+ */
+static int cms_parse ( struct cms_signature *sig,
+		       const struct asn1_cursor *raw ) {
+	struct asn1_cursor cursor;
+	struct cms_signer_info *info;
+	int rc;
+
+	/* Enter contentInfo */
+	memcpy ( &cursor, raw, sizeof ( cursor ) );
+	asn1_enter ( &cursor, ASN1_SEQUENCE );
+
+	/* Parse contentType */
+
+	if ( ( rc = cms_parse_content_type ( sig, &cursor ) ) != 0 )
+		return rc;
+	asn1_skip_any ( &cursor );
+
+	/* Enter content */
+	asn1_enter ( &cursor, ASN1_EXPLICIT_TAG ( 0 ) );
+
+	/* Enter signedData */
+	asn1_enter ( &cursor, ASN1_SEQUENCE );
+
+	/* Skip version */
+	asn1_skip ( &cursor, ASN1_INTEGER );
+
+	/* Skip digestAlgorithms */
+	asn1_skip ( &cursor, ASN1_SET );
+
+	/* Skip encapContentInfo */
+	asn1_skip ( &cursor, ASN1_SEQUENCE );
+
+	/* Parse certificates */
+	if ( ( rc = cms_parse_certificates ( sig, &cursor ) ) != 0 )
+		return rc;
+	asn1_skip_any ( &cursor );
+
+	/* Skip crls, if present */
+	asn1_skip_if_exists ( &cursor, ASN1_EXPLICIT_TAG ( 1 ) );
+
+	/* Enter signerInfos */
+	asn1_enter ( &cursor, ASN1_SET );
+
+	/* Add each signerInfo.  Errors are handled by ensuring that
+	 * cms_put() will always be able to free any allocated memory.
+	 */
+	while ( cursor.len ) {
+
+		/* Allocate signer information block */
+		info = zalloc ( sizeof ( *info ) );
+		if ( ! info )
+			return -ENOMEM;
+		list_add ( &info->list, &sig->info );
+
+		/* Allocate certificate chain */
+		info->chain = x509_alloc_chain();
+		if ( ! info->chain )
+			return -ENOMEM;
+
+		/* Parse signerInfo */
+		if ( ( rc = cms_parse_signer_info ( sig, info,
+						    &cursor ) ) != 0 )
+			return rc;
+		asn1_skip_any ( &cursor );
+	}
+
+	return 0;
+}
+
+/**
+ * Free CMS signature
+ *
+ * @v refcnt		Reference count
+ */
+static void cms_free ( struct refcnt *refcnt ) {
+	struct cms_signature *sig =
+		container_of ( refcnt, struct cms_signature, refcnt );
+	struct cms_signer_info *info;
+	struct cms_signer_info *tmp;
+
+	list_for_each_entry_safe ( info, tmp, &sig->info, list ) {
+		list_del ( &info->list );
+		x509_chain_put ( info->chain );
+		free ( info->signature );
+		free ( info );
+	}
+	x509_chain_put ( sig->certificates );
+	free ( sig );
+}
+
+/**
+ * Create CMS signature
+ *
+ * @v data		Raw signature data
+ * @v len		Length of raw data
+ * @ret sig		CMS signature
+ * @ret rc		Return status code
+ *
+ * On success, the caller holds a reference to the CMS signature, and
+ * is responsible for ultimately calling cms_put().
+ */
+int cms_signature ( const void *data, size_t len, struct cms_signature **sig ) {
+	struct asn1_cursor cursor;
+	int rc;
+
+	/* Allocate and initialise signature */
+	*sig = zalloc ( sizeof ( **sig ) );
+	if ( ! *sig ) {
+		rc = -ENOMEM;
+		goto err_alloc;
+	}
+	ref_init ( &(*sig)->refcnt, cms_free );
+	INIT_LIST_HEAD ( &(*sig)->info );
+
+	/* Allocate certificate list */
+	(*sig)->certificates = x509_alloc_chain();
+	if ( ! (*sig)->certificates ) {
+		rc = -ENOMEM;
+		goto err_alloc_chain;
+	}
+
+	/* Initialise cursor */
+	cursor.data = data;
+	cursor.len = len;
+	asn1_shrink_any ( &cursor );
+
+	/* Parse signature */
+	if ( ( rc = cms_parse ( *sig, &cursor ) ) != 0 )
+		goto err_parse;
+
+	return 0;
+
+ err_parse:
+ err_alloc_chain:
+	cms_put ( *sig );
+ err_alloc:
+	return rc;
+}
+
+/**
+ * Calculate digest of CMS-signed data
+ *
+ * @v sig		CMS signature
+ * @v info		Signer information
+ * @v data		Signed data
+ * @v len		Length of signed data
+ * @v out		Digest output
+ */
+static void cms_digest ( struct cms_signature *sig,
+			 struct cms_signer_info *info,
+			 userptr_t data, size_t len, void *out ) {
+	struct digest_algorithm *digest = info->digest;
+	uint8_t ctx[ digest->ctxsize ];
+	uint8_t block[ digest->blocksize ];
+	size_t offset = 0;
+	size_t frag_len;
+
+	/* Initialise digest */
+	digest_init ( digest, ctx );
+
+	/* Process data one block at a time */
+	while ( len ) {
+		frag_len = len;
+		if ( frag_len > sizeof ( block ) )
+			frag_len = sizeof ( block );
+		copy_from_user ( block, data, offset, frag_len );
+		digest_update ( digest, ctx, block, frag_len );
+		offset += frag_len;
+		len -= frag_len;
+	}
+
+	/* Finalise digest */
+	digest_final ( digest, ctx, out );
+
+	DBGC ( sig, "CMS %p/%p digest value:\n", sig, info );
+	DBGC_HDA ( sig, 0, out, digest->digestsize );
+}
+
+/**
+ * Verify digest of CMS-signed data
+ *
+ * @v sig		CMS signature
+ * @v info		Signer information
+ * @v cert		Corresponding certificate
+ * @v data		Signed data
+ * @v len		Length of signed data
+ * @ret rc		Return status code
+ */
+static int cms_verify_digest ( struct cms_signature *sig,
+			       struct cms_signer_info *info,
+			       struct x509_certificate *cert,
+			       userptr_t data, size_t len ) {
+	struct digest_algorithm *digest = info->digest;
+	struct pubkey_algorithm *pubkey = info->pubkey;
+	struct x509_public_key *public_key = &cert->subject.public_key;
+	uint8_t digest_out[ digest->digestsize ];
+	uint8_t ctx[ pubkey->ctxsize ];
+	int rc;
+
+	/* Generate digest */
+	cms_digest ( sig, info, data, len, digest_out );
+
+	/* Initialise public-key algorithm */
+	if ( ( rc = pubkey_init ( pubkey, ctx, public_key->raw.data,
+				  public_key->raw.len ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not initialise public key: %s\n",
+		       sig, info, strerror ( rc ) );
+		goto err_init;
+	}
+
+	/* Verify digest */
+	if ( ( rc = pubkey_verify ( pubkey, ctx, digest, digest_out,
+				    info->signature,
+				    info->signature_len ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p signature verification failed: %s\n",
+		       sig, info, strerror ( rc ) );
+		goto err_verify;
+	}
+
+ err_verify:
+	pubkey_final ( pubkey, ctx );
+ err_init:
+	return rc;
+}
+
+/**
+ * Verify CMS signature signer information
+ *
+ * @v sig		CMS signature
+ * @v info		Signer information
+ * @v data		Signed data
+ * @v len		Length of signed data
+ * @v time		Time at which to validate certificates
+ * @v store		Certificate store, or NULL to use default
+ * @v root		Root certificate list, or NULL to use default
+ * @ret rc		Return status code
+ */
+static int cms_verify_signer_info ( struct cms_signature *sig,
+				    struct cms_signer_info *info,
+				    userptr_t data, size_t len,
+				    time_t time, struct x509_chain *store,
+				    struct x509_root *root ) {
+	struct x509_certificate *cert;
+	int rc;
+
+	/* Validate certificate chain */
+	if ( ( rc = x509_validate_chain ( info->chain, time, store,
+					  root ) ) != 0 ) {
+		DBGC ( sig, "CMS %p/%p could not validate chain: %s\n",
+		       sig, info, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Extract code-signing certificate */
+	cert = x509_first ( info->chain );
+	assert ( cert != NULL );
+
+	/* Check that certificate can create digital signatures */
+	if ( ! ( cert->extensions.usage.bits & X509_DIGITAL_SIGNATURE ) ) {
+		DBGC ( sig, "CMS %p/%p certificate cannot create signatures\n",
+		       sig, info );
+		return -EACCES_NON_SIGNING;
+	}
+
+	/* Check that certificate can sign code */
+	if ( ! ( cert->extensions.ext_usage.bits & X509_CODE_SIGNING ) ) {
+		DBGC ( sig, "CMS %p/%p certificate is not code-signing\n",
+		       sig, info );
+		return -EACCES_NON_CODE_SIGNING;
+	}
+
+	/* Verify digest */
+	if ( ( rc = cms_verify_digest ( sig, info, cert, data, len ) ) != 0 )
+		return rc;
+
+	return 0;
+}
+
+/**
+ * Verify CMS signature
+ *
+ * @v sig		CMS signature
+ * @v data		Signed data
+ * @v len		Length of signed data
+ * @v name		Required common name, or NULL to check all signatures
+ * @v time		Time at which to validate certificates
+ * @v store		Certificate store, or NULL to use default
+ * @v root		Root certificate list, or NULL to use default
+ * @ret rc		Return status code
+ */
+int cms_verify ( struct cms_signature *sig, userptr_t data, size_t len,
+		 const char *name, time_t time, struct x509_chain *store,
+		 struct x509_root *root ) {
+	struct cms_signer_info *info;
+	struct x509_certificate *cert;
+	int count = 0;
+	int rc;
+
+	/* Verify using all signerInfos */
+	list_for_each_entry ( info, &sig->info, list ) {
+		cert = x509_first ( info->chain );
+		if ( name && ( x509_check_name ( cert, name ) != 0 ) )
+			continue;
+		if ( ( rc = cms_verify_signer_info ( sig, info, data, len, time,
+						     store, root ) ) != 0 )
+			return rc;
+		count++;
+	}
+
+	/* Check that we have verified at least one signature */
+	if ( count == 0 ) {
+		if ( name ) {
+			DBGC ( sig, "CMS %p had no signatures matching name "
+			       "%s\n", sig, name );
+			return -EACCES_WRONG_NAME;
+		} else {
+			DBGC ( sig, "CMS %p had no signatures\n", sig );
+			return -EACCES_NO_SIGNATURES;
+		}
+	}
+
+	return 0;
+}