Merge tag 'efi-2020-10-rc1-5' of https://gitlab.denx.de/u-boot/custodians/u-boot-efi

Pull request for UEFI sub-system for efi-2020-10-rc1 (5)

The series provides bug fixes for:

* crash in OS when accessing UEFI variables
* returning from UEFI fit images to U-Boot
* error handling for variable services provided by OP-TEE
* error handling in EFI_FILE_PROTOCOL.Read()
* missing function documentation

The first patches needed to use intermediate certificates for
secure boot are added. (The rest of the series requires
updating sbsigntool in our CI systems.)

Logging is enabled in the bootefi command.

12 files changed, 802 insertions, 34 deletions

diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig
index 2b221b915a..6369bafac0 100644
--- a/lib/crypto/Kconfig
+++ b/lib/crypto/Kconfig
@@ -49,4 +49,7 @@ config PKCS7_MESSAGE_PARSER
 	  This option provides support for parsing PKCS#7 format messages for
 	  signature data and provides the ability to verify the signature.
 
+config PKCS7_VERIFY
+	bool
+
 endif # ASYMMETRIC_KEY_TYPE
diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile
index 8267fee0a7..f3a414525d 100644
--- a/lib/crypto/Makefile
+++ b/lib/crypto/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_PKCS7_MESSAGE_PARSER) += pkcs7_message.o
 pkcs7_message-y := \
 	pkcs7.asn1.o \
 	pkcs7_parser.o
+obj-$(CONFIG_PKCS7_VERIFY) += pkcs7_verify.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_verify.c b/lib/crypto/pkcs7_verify.c
new file mode 100644
index 0000000000..320ba49f79
--- /dev/null
+++ b/lib/crypto/pkcs7_verify.c
@@ -0,0 +1,657 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Verify the signature on a PKCS#7 message.
+ *
+ * Imported from crypto/asymmetric_keys/pkcs7_verify.c of linux 5.7
+ * with modification marked as __UBOOT__.
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) "PKCS7: "fmt
+#ifdef __UBOOT__
+#include <image.h>
+#include <string.h>
+#include <linux/bitops.h>
+#include <linux/compat.h>
+#include <linux/asn1.h>
+#include <u-boot/rsa-checksum.h>
+#include <crypto/public_key.h>
+#include <crypto/pkcs7_parser.h>
+#else
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/asn1.h>
+#include <crypto/hash.h>
+#include <crypto/hash_info.h>
+#include <crypto/public_key.h>
+#include "pkcs7_parser.h"
+#endif
+
+/*
+ * pkcs7_digest - Digest the relevant parts of the PKCS#7 data
+ * @pkcs7:	PKCS7 Signed Data
+ * @sinfo:	PKCS7 Signed Info
+ *
+ * Digest the relevant parts of the PKCS#7 data, @pkcs7, using signature
+ * information in @sinfo. But if there are authentication attributes,
+ * i.e. signed image case, the digest must be calculated against
+ * the authentication attributes.
+ *
+ * Return:	0 - on success, non-zero error code - otherwise
+ */
+#ifdef __UBOOT__
+static int pkcs7_digest(struct pkcs7_message *pkcs7,
+			struct pkcs7_signed_info *sinfo)
+{
+	struct public_key_signature *sig = sinfo->sig;
+	struct image_region regions[2];
+	int ret = 0;
+
+	/* The digest was calculated already. */
+	if (sig->digest)
+		return 0;
+
+	if (!sinfo->sig->hash_algo)
+		return -ENOPKG;
+	if (!strcmp(sinfo->sig->hash_algo, "sha256"))
+		sig->digest_size = SHA256_SUM_LEN;
+	else if (!strcmp(sinfo->sig->hash_algo, "sha1"))
+		sig->digest_size = SHA1_SUM_LEN;
+	else
+		return -ENOPKG;
+
+	sig->digest = calloc(1, sig->digest_size);
+	if (!sig->digest) {
+		pr_warn("Sig %u: Out of memory\n", sinfo->index);
+		return -ENOMEM;
+	}
+
+	regions[0].data = pkcs7->data;
+	regions[0].size = pkcs7->data_len;
+
+	/* Digest the message [RFC2315 9.3] */
+	hash_calculate(sinfo->sig->hash_algo, regions, 1, sig->digest);
+
+	/* However, if there are authenticated attributes, there must be a
+	 * message digest attribute amongst them which corresponds to the
+	 * digest we just calculated.
+	 */
+	if (sinfo->authattrs) {
+		u8 tag;
+
+		if (!sinfo->msgdigest) {
+			pr_warn("Sig %u: No messageDigest\n", sinfo->index);
+			ret = -EKEYREJECTED;
+			goto error;
+		}
+
+		if (sinfo->msgdigest_len != sig->digest_size) {
+			pr_debug("Sig %u: Invalid digest size (%u)\n",
+				 sinfo->index, sinfo->msgdigest_len);
+			ret = -EBADMSG;
+			goto error;
+		}
+
+		if (memcmp(sig->digest, sinfo->msgdigest,
+			   sinfo->msgdigest_len) != 0) {
+			pr_debug("Sig %u: Message digest doesn't match\n",
+				 sinfo->index);
+			ret = -EKEYREJECTED;
+			goto error;
+		}
+
+		/* We then calculate anew, using the authenticated attributes
+		 * as the contents of the digest instead.  Note that we need to
+		 * convert the attributes from a CONT.0 into a SET before we
+		 * hash it.
+		 */
+		memset(sig->digest, 0, sig->digest_size);
+
+		tag = 0x31;
+		regions[0].data = &tag;
+		regions[0].size = 1;
+		regions[1].data = sinfo->authattrs;
+		regions[1].size = sinfo->authattrs_len;
+
+		hash_calculate(sinfo->sig->hash_algo, regions, 2, sig->digest);
+
+		ret = 0;
+	}
+error:
+	return ret;
+}
+#else /* !__UBOOT__ */
+static int pkcs7_digest(struct pkcs7_message *pkcs7,
+			struct pkcs7_signed_info *sinfo)
+{
+	struct public_key_signature *sig = sinfo->sig;
+	struct crypto_shash *tfm;
+	struct shash_desc *desc;
+	size_t desc_size;
+	int ret;
+
+	kenter(",%u,%s", sinfo->index, sinfo->sig->hash_algo);
+
+	/* The digest was calculated already. */
+	if (sig->digest)
+		return 0;
+
+	if (!sinfo->sig->hash_algo)
+		return -ENOPKG;
+
+	/* Allocate the hashing algorithm we're going to need and find out how
+	 * big the hash operational data will be.
+	 */
+	tfm = crypto_alloc_shash(sinfo->sig->hash_algo, 0, 0);
+	if (IS_ERR(tfm))
+		return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm);
+
+	desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
+	sig->digest_size = crypto_shash_digestsize(tfm);
+
+	ret = -ENOMEM;
+	sig->digest = kmalloc(sig->digest_size, GFP_KERNEL);
+	if (!sig->digest)
+		goto error_no_desc;
+
+	desc = kzalloc(desc_size, GFP_KERNEL);
+	if (!desc)
+		goto error_no_desc;
+
+	desc->tfm   = tfm;
+
+	/* Digest the message [RFC2315 9.3] */
+	ret = crypto_shash_digest(desc, pkcs7->data, pkcs7->data_len,
+				  sig->digest);
+	if (ret < 0)
+		goto error;
+	pr_devel("MsgDigest = [%*ph]\n", 8, sig->digest);
+
+	/* However, if there are authenticated attributes, there must be a
+	 * message digest attribute amongst them which corresponds to the
+	 * digest we just calculated.
+	 */
+	if (sinfo->authattrs) {
+		u8 tag;
+
+		if (!sinfo->msgdigest) {
+			pr_warn("Sig %u: No messageDigest\n", sinfo->index);
+			ret = -EKEYREJECTED;
+			goto error;
+		}
+
+		if (sinfo->msgdigest_len != sig->digest_size) {
+			pr_debug("Sig %u: Invalid digest size (%u)\n",
+				 sinfo->index, sinfo->msgdigest_len);
+			ret = -EBADMSG;
+			goto error;
+		}
+
+		if (memcmp(sig->digest, sinfo->msgdigest,
+			   sinfo->msgdigest_len) != 0) {
+			pr_debug("Sig %u: Message digest doesn't match\n",
+				 sinfo->index);
+			ret = -EKEYREJECTED;
+			goto error;
+		}
+
+		/* We then calculate anew, using the authenticated attributes
+		 * as the contents of the digest instead.  Note that we need to
+		 * convert the attributes from a CONT.0 into a SET before we
+		 * hash it.
+		 */
+		memset(sig->digest, 0, sig->digest_size);
+
+		ret = crypto_shash_init(desc);
+		if (ret < 0)
+			goto error;
+		tag = ASN1_CONS_BIT | ASN1_SET;
+		ret = crypto_shash_update(desc, &tag, 1);
+		if (ret < 0)
+			goto error;
+		ret = crypto_shash_finup(desc, sinfo->authattrs,
+					 sinfo->authattrs_len, sig->digest);
+		if (ret < 0)
+			goto error;
+		pr_devel("AADigest = [%*ph]\n", 8, sig->digest);
+	}
+
+error:
+	kfree(desc);
+error_no_desc:
+	crypto_free_shash(tfm);
+	kleave(" = %d", ret);
+	return ret;
+}
+
+int pkcs7_get_digest(struct pkcs7_message *pkcs7, const u8 **buf, u32 *len,
+		     enum hash_algo *hash_algo)
+{
+	struct pkcs7_signed_info *sinfo = pkcs7->signed_infos;
+	int i, ret;
+
+	/*
+	 * This function doesn't support messages with more than one signature.
+	 */
+	if (sinfo == NULL || sinfo->next != NULL)
+		return -EBADMSG;
+
+	ret = pkcs7_digest(pkcs7, sinfo);
+	if (ret)
+		return ret;
+
+	*buf = sinfo->sig->digest;
+	*len = sinfo->sig->digest_size;
+
+	for (i = 0; i < HASH_ALGO__LAST; i++)
+		if (!strcmp(hash_algo_name[i], sinfo->sig->hash_algo)) {
+			*hash_algo = i;
+			break;
+		}
+
+	return 0;
+}
+#endif /* !__UBOOT__ */
+
+/*
+ * Find the key (X.509 certificate) to use to verify a PKCS#7 message.  PKCS#7
+ * uses the issuer's name and the issuing certificate serial number for
+ * matching purposes.  These must match the certificate issuer's name (not
+ * subject's name) and the certificate serial number [RFC 2315 6.7].
+ */
+static int pkcs7_find_key(struct pkcs7_message *pkcs7,
+			  struct pkcs7_signed_info *sinfo)
+{
+	struct x509_certificate *x509;
+	unsigned certix = 1;
+
+	kenter("%u", sinfo->index);
+
+	for (x509 = pkcs7->certs; x509; x509 = x509->next, certix++) {
+		/* I'm _assuming_ that the generator of the PKCS#7 message will
+		 * encode the fields from the X.509 cert in the same way in the
+		 * PKCS#7 message - but I can't be 100% sure of that.  It's
+		 * possible this will need element-by-element comparison.
+		 */
+		if (!asymmetric_key_id_same(x509->id, sinfo->sig->auth_ids[0]))
+			continue;
+		pr_devel("Sig %u: Found cert serial match X.509[%u]\n",
+			 sinfo->index, certix);
+
+		if (strcmp(x509->pub->pkey_algo, sinfo->sig->pkey_algo) != 0) {
+			pr_warn("Sig %u: X.509 algo and PKCS#7 sig algo don't match\n",
+				sinfo->index);
+			continue;
+		}
+
+		sinfo->signer = x509;
+		return 0;
+	}
+
+	/* The relevant X.509 cert isn't found here, but it might be found in
+	 * the trust keyring.
+	 */
+	pr_debug("Sig %u: Issuing X.509 cert not found (#%*phN)\n",
+		 sinfo->index,
+		 sinfo->sig->auth_ids[0]->len, sinfo->sig->auth_ids[0]->data);
+	return 0;
+}
+
+/*
+ * pkcs7_verify_sig_chain - Verify the internal certificate chain as best
+ *                          as we can.
+ * @pkcs7:	PKCS7 Signed Data
+ * @sinfo:	PKCS7 Signed Info
+ * @signer:	Singer's certificate
+ *
+ * Build up and verify the internal certificate chain against a signature
+ * in @sinfo, using certificates contained in @pkcs7 as best as we can.
+ * If the chain reaches the end, the last certificate will be returned
+ * in @signer.
+ *
+ * Return:	0 - on success, non-zero error code - otherwise
+ */
+#ifdef __UBOOT__
+static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
+				  struct pkcs7_signed_info *sinfo,
+				  struct x509_certificate **signer)
+#else
+static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
+				  struct pkcs7_signed_info *sinfo)
+#endif
+{
+	struct public_key_signature *sig;
+	struct x509_certificate *x509 = sinfo->signer, *p;
+	struct asymmetric_key_id *auth;
+	int ret;
+
+	kenter("");
+
+	*signer = NULL;
+
+	for (p = pkcs7->certs; p; p = p->next)
+		p->seen = false;
+
+	for (;;) {
+		pr_debug("verify %s: %*phN\n",
+			 x509->subject,
+			 x509->raw_serial_size, x509->raw_serial);
+		x509->seen = true;
+
+		if (x509->blacklisted) {
+			/* If this cert is blacklisted, then mark everything
+			 * that depends on this as blacklisted too.
+			 */
+			sinfo->blacklisted = true;
+			for (p = sinfo->signer; p != x509; p = p->signer)
+				p->blacklisted = true;
+			pr_debug("- blacklisted\n");
+#ifdef __UBOOT__
+			*signer = x509;
+#endif
+			return 0;
+		}
+
+		if (x509->unsupported_key)
+			goto unsupported_crypto_in_x509;
+
+		pr_debug("- issuer %s\n", x509->issuer);
+		sig = x509->sig;
+		if (sig->auth_ids[0])
+			pr_debug("- authkeyid.id %*phN\n",
+				 sig->auth_ids[0]->len, sig->auth_ids[0]->data);
+		if (sig->auth_ids[1])
+			pr_debug("- authkeyid.skid %*phN\n",
+				 sig->auth_ids[1]->len, sig->auth_ids[1]->data);
+
+		if (x509->self_signed) {
+			/* If there's no authority certificate specified, then
+			 * the certificate must be self-signed and is the root
+			 * of the chain.  Likewise if the cert is its own
+			 * authority.
+			 */
+			if (x509->unsupported_sig)
+				goto unsupported_crypto_in_x509;
+			x509->signer = x509;
+			pr_debug("- self-signed\n");
+#ifdef __UBOOT__
+			*signer = x509;
+#endif
+			return 0;
+		}
+
+		/* Look through the X.509 certificates in the PKCS#7 message's
+		 * list to see if the next one is there.
+		 */
+		auth = sig->auth_ids[0];
+		if (auth) {
+			pr_debug("- want %*phN\n", auth->len, auth->data);
+			for (p = pkcs7->certs; p; p = p->next) {
+				pr_debug("- cmp [%u] %*phN\n",
+					 p->index, p->id->len, p->id->data);
+				if (asymmetric_key_id_same(p->id, auth))
+					goto found_issuer_check_skid;
+			}
+		} else if (sig->auth_ids[1]) {
+			auth = sig->auth_ids[1];
+			pr_debug("- want %*phN\n", auth->len, auth->data);
+			for (p = pkcs7->certs; p; p = p->next) {
+				if (!p->skid)
+					continue;
+				pr_debug("- cmp [%u] %*phN\n",
+					 p->index, p->skid->len, p->skid->data);
+				if (asymmetric_key_id_same(p->skid, auth))
+					goto found_issuer;
+			}
+		}
+
+		/* We didn't find the root of this chain */
+		pr_debug("- top\n");
+#ifdef __UBOOT__
+		*signer = x509;
+#endif
+		return 0;
+
+	found_issuer_check_skid:
+		/* We matched issuer + serialNumber, but if there's an
+		 * authKeyId.keyId, that must match the CA subjKeyId also.
+		 */
+		if (sig->auth_ids[1] &&
+		    !asymmetric_key_id_same(p->skid, sig->auth_ids[1])) {
+			pr_warn("Sig %u: X.509 chain contains auth-skid nonmatch (%u->%u)\n",
+				sinfo->index, x509->index, p->index);
+			return -EKEYREJECTED;
+		}
+	found_issuer:
+		pr_debug("- subject %s\n", p->subject);
+		if (p->seen) {
+			pr_warn("Sig %u: X.509 chain contains loop\n",
+				sinfo->index);
+#ifdef __UBOOT__
+			*signer = p;
+#endif
+			return 0;
+		}
+		ret = public_key_verify_signature(p->pub, x509->sig);
+		if (ret < 0)
+			return ret;
+		x509->signer = p;
+		if (x509 == p) {
+			pr_debug("- self-signed\n");
+#ifdef __UBOOT__
+			*signer = p;
+#endif
+			return 0;
+		}
+		x509 = p;
+#ifndef __UBOOT__
+		might_sleep();
+#endif
+	}
+
+unsupported_crypto_in_x509:
+	/* Just prune the certificate chain at this point if we lack some
+	 * crypto module to go further.  Note, however, we don't want to set
+	 * sinfo->unsupported_crypto as the signed info block may still be
+	 * validatable against an X.509 cert lower in the chain that we have a
+	 * trusted copy of.
+	 */
+	return 0;
+}
+
+/*
+ * pkcs7_verify_one - Verify one signed information block from a PKCS#7
+ *                    message.
+ * @pkcs7:	PKCS7 Signed Data
+ * @sinfo:	PKCS7 Signed Info
+ * @signer:	Signer's certificate
+ *
+ * Verify one signature in @sinfo and follow the certificate chain.
+ * If the chain reaches the end, the last certificate will be returned
+ * in @signer.
+ *
+ * Return:	0 - on success, non-zero error code - otherwise
+ */
+#ifdef __UBOOT__
+int pkcs7_verify_one(struct pkcs7_message *pkcs7,
+		     struct pkcs7_signed_info *sinfo,
+		     struct x509_certificate **signer)
+#else
+static int pkcs7_verify_one(struct pkcs7_message *pkcs7,
+			    struct pkcs7_signed_info *sinfo)
+#endif
+{
+	int ret;
+
+	kenter(",%u", sinfo->index);
+
+	/* First of all, digest the data in the PKCS#7 message and the
+	 * signed information block
+	 */
+	ret = pkcs7_digest(pkcs7, sinfo);
+	if (ret < 0)
+		return ret;
+
+	/* Find the key for the signature if there is one */
+	ret = pkcs7_find_key(pkcs7, sinfo);
+	if (ret < 0)
+		return ret;
+
+	if (!sinfo->signer)
+		return 0;
+
+	pr_devel("Using X.509[%u] for sig %u\n",
+		 sinfo->signer->index, sinfo->index);
+
+	/* Check that the PKCS#7 signing time is valid according to the X.509
+	 * certificate.  We can't, however, check against the system clock
+	 * since that may not have been set yet and may be wrong.
+	 */
+	if (test_bit(sinfo_has_signing_time, &sinfo->aa_set)) {
+		if (sinfo->signing_time < sinfo->signer->valid_from ||
+		    sinfo->signing_time > sinfo->signer->valid_to) {
+			pr_warn("Message signed outside of X.509 validity window\n");
+			return -EKEYREJECTED;
+		}
+	}
+
+	/* Verify the PKCS#7 binary against the key */
+	ret = public_key_verify_signature(sinfo->signer->pub, sinfo->sig);
+	if (ret < 0)
+		return ret;
+
+	pr_devel("Verified signature %u\n", sinfo->index);
+
+	/* Verify the internal certificate chain */
+	return pkcs7_verify_sig_chain(pkcs7, sinfo, signer);
+}
+
+#ifndef __UBOOT__
+/**
+ * pkcs7_verify - Verify a PKCS#7 message
+ * @pkcs7: The PKCS#7 message to be verified
+ * @usage: The use to which the key is being put
+ *
+ * Verify a PKCS#7 message is internally consistent - that is, the data digest
+ * matches the digest in the AuthAttrs and any signature in the message or one
+ * of the X.509 certificates it carries that matches another X.509 cert in the
+ * message can be verified.
+ *
+ * This does not look to match the contents of the PKCS#7 message against any
+ * external public keys.
+ *
+ * Returns, in order of descending priority:
+ *
+ *  (*) -EKEYREJECTED if a key was selected that had a usage restriction at
+ *      odds with the specified usage, or:
+ *
+ *  (*) -EKEYREJECTED if a signature failed to match for which we found an
+ *	appropriate X.509 certificate, or:
+ *
+ *  (*) -EBADMSG if some part of the message was invalid, or:
+ *
+ *  (*) 0 if a signature chain passed verification, or:
+ *
+ *  (*) -EKEYREJECTED if a blacklisted key was encountered, or:
+ *
+ *  (*) -ENOPKG if none of the signature chains are verifiable because suitable
+ *	crypto modules couldn't be found.
+ */
+int pkcs7_verify(struct pkcs7_message *pkcs7,
+		 enum key_being_used_for usage)
+{
+	struct pkcs7_signed_info *sinfo;
+	int actual_ret = -ENOPKG;
+	int ret;
+
+	kenter("");
+
+	switch (usage) {
+	case VERIFYING_MODULE_SIGNATURE:
+		if (pkcs7->data_type != OID_data) {
+			pr_warn("Invalid module sig (not pkcs7-data)\n");
+			return -EKEYREJECTED;
+		}
+		if (pkcs7->have_authattrs) {
+			pr_warn("Invalid module sig (has authattrs)\n");
+			return -EKEYREJECTED;
+		}
+		break;
+	case VERIFYING_FIRMWARE_SIGNATURE:
+		if (pkcs7->data_type != OID_data) {
+			pr_warn("Invalid firmware sig (not pkcs7-data)\n");
+			return -EKEYREJECTED;
+		}
+		if (!pkcs7->have_authattrs) {
+			pr_warn("Invalid firmware sig (missing authattrs)\n");
+			return -EKEYREJECTED;
+		}
+		break;
+	case VERIFYING_KEXEC_PE_SIGNATURE:
+		if (pkcs7->data_type != OID_msIndirectData) {
+			pr_warn("Invalid kexec sig (not Authenticode)\n");
+			return -EKEYREJECTED;
+		}
+		/* Authattr presence checked in parser */
+		break;
+	case VERIFYING_UNSPECIFIED_SIGNATURE:
+		if (pkcs7->data_type != OID_data) {
+			pr_warn("Invalid unspecified sig (not pkcs7-data)\n");
+			return -EKEYREJECTED;
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	for (sinfo = pkcs7->signed_infos; sinfo; sinfo = sinfo->next) {
+		ret = pkcs7_verify_one(pkcs7, sinfo);
+		if (sinfo->blacklisted) {
+			if (actual_ret == -ENOPKG)
+				actual_ret = -EKEYREJECTED;
+			continue;
+		}
+		if (ret < 0) {
+			if (ret == -ENOPKG) {
+				sinfo->unsupported_crypto = true;
+				continue;
+			}
+			kleave(" = %d", ret);
+			return ret;
+		}
+		actual_ret = 0;
+	}
+
+	kleave(" = %d", actual_ret);
+	return actual_ret;
+}
+EXPORT_SYMBOL_GPL(pkcs7_verify);
+
+/**
+ * pkcs7_supply_detached_data - Supply the data needed to verify a PKCS#7 message
+ * @pkcs7: The PKCS#7 message
+ * @data: The data to be verified
+ * @datalen: The amount of data
+ *
+ * Supply the detached data needed to verify a PKCS#7 message.  Note that no
+ * attempt to retain/pin the data is made.  That is left to the caller.  The
+ * data will not be modified by pkcs7_verify() and will not be freed when the
+ * PKCS#7 message is freed.
+ *
+ * Returns -EINVAL if data is already supplied in the message, 0 otherwise.
+ */
+int pkcs7_supply_detached_data(struct pkcs7_message *pkcs7,
+			       const void *data, size_t datalen)
+{
+	if (pkcs7->data) {
+		pr_debug("Data already supplied\n");
+		return -EINVAL;
+	}
+	pkcs7->data = data;
+	pkcs7->data_len = datalen;
+	return 0;
+}
+#endif /* __UBOOT__ */
diff --git a/lib/crypto/public_key.c b/lib/crypto/public_key.c
index e12ebbb3d0..a8f7fbed45 100644
--- a/lib/crypto/public_key.c
+++ b/lib/crypto/public_key.c
@@ -25,7 +25,10 @@
 #include <keys/asymmetric-subtype.h>
 #endif
 #include <crypto/public_key.h>
-#ifndef __UBOOT__
+#ifdef __UBOOT__
+#include <image.h>
+#include <u-boot/rsa.h>
+#else
 #include <crypto/akcipher.h>
 #endif
 
@@ -80,6 +83,71 @@ void public_key_signature_free(struct public_key_signature *sig)
 }
 EXPORT_SYMBOL_GPL(public_key_signature_free);
 
+/**
+ * public_key_verify_signature - Verify a signature using a public key.
+ *
+ * @pkey:	Public key
+ * @sig:	Signature
+ *
+ * Verify a signature, @sig, using a RSA public key, @pkey.
+ *
+ * Return:	0 - verified, non-zero error code - otherwise
+ */
+int public_key_verify_signature(const struct public_key *pkey,
+				const struct public_key_signature *sig)
+{
+	struct image_sign_info info;
+	struct image_region region;
+	int ret;
+
+	pr_devel("==>%s()\n", __func__);
+
+	if (!pkey || !sig)
+		return -EINVAL;
+
+	if (pkey->key_is_private)
+		return -EINVAL;
+
+	memset(&info, '\0', sizeof(info));
+	info.padding = image_get_padding_algo("pkcs-1.5");
+	/*
+	 * Note: image_get_[checksum|crypto]_algo takes a string
+	 * argument like "<checksum>,<crypto>"
+	 * TODO: support other hash algorithms
+	 */
+	if (strcmp(sig->pkey_algo, "rsa") || (sig->s_size * 8) != 2048) {
+		pr_warn("Encryption is not RSA2048: %s%d\n",
+			sig->pkey_algo, sig->s_size * 8);
+		return -ENOPKG;
+	}
+	if (!strcmp(sig->hash_algo, "sha1")) {
+		info.checksum = image_get_checksum_algo("sha1,rsa2048");
+		info.name = "sha1,rsa2048";
+	} else if (!strcmp(sig->hash_algo, "sha256")) {
+		info.checksum = image_get_checksum_algo("sha256,rsa2048");
+		info.name = "sha256,rsa2048";
+	} else {
+		pr_warn("unknown msg digest algo: %s\n", sig->hash_algo);
+		return -ENOPKG;
+	}
+	info.crypto = image_get_crypto_algo(info.name);
+	if (IS_ERR(info.checksum) || IS_ERR(info.crypto))
+		return -ENOPKG;
+
+	info.key = pkey->key;
+	info.keylen = pkey->keylen;
+
+	region.data = sig->digest;
+	region.size = sig->digest_size;
+
+	if (rsa_verify_with_pkey(&info, sig->digest, sig->s, sig->s_size))
+		ret = -EKEYREJECTED;
+	else
+		ret = 0;
+
+	pr_devel("<==%s() = %d\n", __func__, ret);
+	return ret;
+}
 #else
 /*
  * Destroy a public key algorithm key.
diff --git a/lib/crypto/x509_cert_parser.c b/lib/crypto/x509_cert_parser.c
index 5f984b9dfd..eb24349460 100644
--- a/lib/crypto/x509_cert_parser.c
+++ b/lib/crypto/x509_cert_parser.c
@@ -142,12 +142,10 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
 	}
 	cert->id = kid;
 
-#ifndef __UBOOT__
 	/* Detect self-signed certificates */
 	ret = x509_check_for_self_signed(cert);
 	if (ret < 0)
 		goto error_decode;
-#endif
 
 	kfree(ctx);
 	return cert;
diff --git a/lib/crypto/x509_public_key.c b/lib/crypto/x509_public_key.c
index 571af9a0ad..91810a8640 100644
--- a/lib/crypto/x509_public_key.c
+++ b/lib/crypto/x509_public_key.c
@@ -8,6 +8,7 @@
 #define pr_fmt(fmt) "X.509: "fmt
 #ifdef __UBOOT__
 #include <common.h>
+#include <image.h>
 #include <dm/devres.h>
 #include <linux/compat.h>
 #include <linux/err.h>
@@ -18,6 +19,7 @@
 #include <linux/kernel.h>
 #ifdef __UBOOT__
 #include <crypto/x509_parser.h>
+#include <u-boot/rsa-checksum.h>
 #else
 #include <linux/slab.h>
 #include <keys/asymmetric-subtype.h>
@@ -35,7 +37,9 @@
 int x509_get_sig_params(struct x509_certificate *cert)
 {
 	struct public_key_signature *sig = cert->sig;
-#ifndef __UBOOT__
+#ifdef __UBOOT__
+	struct image_region region;
+#else
 	struct crypto_shash *tfm;
 	struct shash_desc *desc;
 	size_t desc_size;
@@ -63,12 +67,25 @@ int x509_get_sig_params(struct x509_certificate *cert)
 	sig->s_size = cert->raw_sig_size;
 
 #ifdef __UBOOT__
-	/*
-	 * Note:
-	 * This part (filling sig->digest) should be implemented if
-	 * x509_check_for_self_signed() is enabled x509_cert_parse().
-	 * Currently, this check won't affect UEFI secure boot.
-	 */
+	if (!sig->hash_algo)
+		return -ENOPKG;
+	if (!strcmp(sig->hash_algo, "sha256"))
+		sig->digest_size = SHA256_SUM_LEN;
+	else if (!strcmp(sig->hash_algo, "sha1"))
+		sig->digest_size = SHA1_SUM_LEN;
+	else
+		return -ENOPKG;
+
+	sig->digest = calloc(1, sig->digest_size);
+	if (!sig->digest)
+		return -ENOMEM;
+
+	region.data = cert->tbs;
+	region.size = cert->tbs_size;
+	hash_calculate(sig->hash_algo, &region, 1, sig->digest);
+
+	/* TODO: is_hash_blacklisted()? */
+
 	ret = 0;
 #else
 	/* Allocate the hashing algorithm we're going to need and find out how
@@ -118,7 +135,6 @@ error:
 	return ret;
 }
 
-#ifndef __UBOOT__
 /*
  * Check for self-signedness in an X.509 cert and if found, check the signature
  * immediately if we can.
@@ -175,6 +191,7 @@ not_self_signed:
 	return 0;
 }
 
+#ifndef __UBOOT__
 /*
  * Attempt to parse a data blob for a key as an X509 certificate.
  */
diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index 0b16554ba2..d49145fc76 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -104,7 +104,15 @@ int __efi_exit_check(void)
 	return ret;
 }
 
-/* Called from do_bootefi_exec() */
+/**
+ * efi_save_gd() - save global data register
+ *
+ * On the ARM architecture gd is mapped to a fixed register (r9 or x18).
+ * As this register may be overwritten by an EFI payload we save it here
+ * and restore it on every callback entered.
+ *
+ * This function is called after relocation from initr_reloc_global_data().
+ */
 void efi_save_gd(void)
 {
 #ifdef CONFIG_ARM
@@ -112,10 +120,12 @@ void efi_save_gd(void)
 #endif
 }
 
-/*
- * Special case handler for error/abort that just forces things back to u-boot
- * world so we can dump out an abort message, without any care about returning
- * back to UEFI world.
+/**
+ * efi_restore_gd() - restore global data register
+ *
+ * On the ARM architecture gd is mapped to a fixed register (r9 or x18).
+ * Restore it after returning from the UEFI world to the value saved via
+ * efi_save_gd().
  */
 void efi_restore_gd(void)
 {
diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
index 670bf2b8ef..7bd1ccec45 100644
--- a/lib/efi_loader/efi_disk.c
+++ b/lib/efi_loader/efi_disk.c
@@ -5,11 +5,14 @@
  *  Copyright (c) 2016 Alexander Graf
  */
 
+#define LOG_CATEGORY LOGC_EFI
+
 #include <common.h>
 #include <blk.h>
 #include <dm.h>
 #include <efi_loader.h>
 #include <fs.h>
+#include <log.h>
 #include <part.h>
 #include <malloc.h>
 
@@ -490,7 +493,7 @@ int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
 		ret = efi_disk_add_dev(parent, dp, if_typename, desc, diskid,
 				       info.start, part, NULL);
 		if (ret != EFI_SUCCESS) {
-			printf("Adding partition %s failed\n", pdevname);
+			log_err("Adding partition %s failed\n", pdevname);
 			continue;
 		}
 		disks++;
@@ -528,16 +531,16 @@ efi_status_t efi_disk_register(void)
 		const char *if_typename = blk_get_if_type_name(desc->if_type);
 
 		/* Add block device for the full device */
-		printf("Scanning disk %s...\n", dev->name);
+		log_info("Scanning disk %s...\n", dev->name);
 		ret = efi_disk_add_dev(NULL, NULL, if_typename,
 					desc, desc->devnum, 0, 0, &disk);
 		if (ret == EFI_NOT_READY) {
-			printf("Disk %s not ready\n", dev->name);
+			log_notice("Disk %s not ready\n", dev->name);
 			continue;
 		}
 		if (ret) {
-			printf("ERROR: failure to add disk device %s, r = %lu\n",
-			       dev->name, ret & ~EFI_ERROR_MASK);
+			log_err("ERROR: failure to add disk device %s, r = %lu\n",
+				dev->name, ret & ~EFI_ERROR_MASK);
 			return ret;
 		}
 		disks++;
@@ -560,7 +563,7 @@ efi_status_t efi_disk_register(void)
 			continue;
 
 		if_typename = cur_drvr->if_typename;
-		printf("Scanning disks on %s...\n", if_typename);
+		log_info("Scanning disks on %s...\n", if_typename);
 		for (i = 0; i < 4; i++) {
 			struct blk_desc *desc;
 			char devname[32] = { 0 }; /* dp->str is u16[32] long */
@@ -578,12 +581,12 @@ efi_status_t efi_disk_register(void)
 			ret = efi_disk_add_dev(NULL, NULL, if_typename, desc,
 					       i, 0, 0, &disk);
 			if (ret == EFI_NOT_READY) {
-				printf("Disk %s not ready\n", devname);
+				log_notice("Disk %s not ready\n", devname);
 				continue;
 			}
 			if (ret) {
-				printf("ERROR: failure to add disk device %s, r = %lu\n",
-				       devname, ret & ~EFI_ERROR_MASK);
+				log_err("ERROR: failure to add disk device %s, r = %lu\n",
+					devname, ret & ~EFI_ERROR_MASK);
 				return ret;
 			}
 			disks++;
@@ -595,7 +598,7 @@ efi_status_t efi_disk_register(void)
 		}
 	}
 #endif
-	printf("Found %d disks\n", disks);
+	log_info("Found %d disks\n", disks);
 
 	return EFI_SUCCESS;
 }
diff --git a/lib/efi_loader/efi_file.c b/lib/efi_loader/efi_file.c
index 19afa69f53..44fafae058 100644
--- a/lib/efi_loader/efi_file.c
+++ b/lib/efi_loader/efi_file.c
@@ -349,6 +349,11 @@ static efi_status_t file_read(struct file_handle *fh, u64 *buffer_size,
 	efi_status_t ret;
 	loff_t file_size;
 
+	if (!buffer) {
+		ret = EFI_INVALID_PARAMETER;
+		return ret;
+	}
+
 	ret = efi_get_file_size(fh, &file_size);
 	if (ret != EFI_SUCCESS)
 		return ret;
@@ -414,6 +419,8 @@ static efi_status_t dir_read(struct file_handle *fh, u64 *buffer_size,
 		fh->dent = dent;
 		return EFI_BUFFER_TOO_SMALL;
 	}
+	if (!buffer)
+		return EFI_INVALID_PARAMETER;
 	fh->dent = NULL;
 
 	*buffer_size = required_size;
@@ -443,7 +450,7 @@ static efi_status_t EFIAPI efi_file_read(struct efi_file_handle *file,
 
 	EFI_ENTRY("%p, %p, %p", file, buffer_size, buffer);
 
-	if (!buffer_size || !buffer) {
+	if (!buffer_size) {
 		ret = EFI_INVALID_PARAMETER;
 		goto error;
 	}
diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
index 91a4551448..78fd8014d9 100644
--- a/lib/efi_loader/efi_runtime.c
+++ b/lib/efi_loader/efi_runtime.c
@@ -144,6 +144,8 @@ efi_status_t efi_init_runtime_supported(void)
  *
  * At runtime memcpy() is not available.
  *
+ * Overlapping memory areas can be copied safely if src >= dest.
+ *
  * @dest:	destination buffer
  * @src:	source buffer
  * @n:		number of bytes to copy
diff --git a/lib/efi_loader/efi_var_mem.c b/lib/efi_loader/efi_var_mem.c
index 7a2dba7dc2..bfa8a56a8f 100644
--- a/lib/efi_loader/efi_var_mem.c
+++ b/lib/efi_loader/efi_var_mem.c
@@ -120,7 +120,8 @@ void __efi_runtime efi_var_mem_del(struct efi_var_entry *var)
 	       ALIGN((uintptr_t)data + var->length, 8);
 	efi_var_buf->length -= (uintptr_t)next - (uintptr_t)var;
 
-	memmove(var, next, (uintptr_t)last - (uintptr_t)next);
+	/* efi_memcpy_runtime() can be used because next >= var. */
+	efi_memcpy_runtime(var, next, (uintptr_t)last - (uintptr_t)next);
 	efi_var_buf->crc32 = crc32(0, (u8 *)efi_var_buf->var,
 				   efi_var_buf->length -
 				   sizeof(struct efi_var_file));
@@ -231,6 +232,7 @@ static void EFIAPI __efi_runtime
 efi_var_mem_notify_virtual_address_map(struct efi_event *event, void *context)
 {
 	efi_convert_pointer(0, (void **)&efi_var_buf);
+	efi_current_var = NULL;
 }
 
 efi_status_t efi_var_mem_init(void)
diff --git a/lib/efi_loader/efi_variable_tee.c b/lib/efi_loader/efi_variable_tee.c
index c042348938..94c4de8703 100644
--- a/lib/efi_loader/efi_variable_tee.c
+++ b/lib/efi_loader/efi_variable_tee.c
@@ -100,25 +100,25 @@ static efi_status_t optee_mm_communicate(void *comm_buf, ulong dsize)
 	param[1].attr = TEE_PARAM_ATTR_TYPE_VALUE_OUTPUT;
 
 	rc = tee_invoke_func(conn.tee, &arg, 2, param);
-	if (rc)
-		return EFI_INVALID_PARAMETER;
 	tee_shm_free(shm);
 	tee_close_session(conn.tee, conn.session);
+	if (rc || arg.ret != TEE_SUCCESS)
+		return EFI_DEVICE_ERROR;
 
 	switch (param[1].u.value.a) {
-	case ARM_SMC_MM_RET_SUCCESS:
+	case ARM_SVC_SPM_RET_SUCCESS:
 		ret = EFI_SUCCESS;
 		break;
 
-	case ARM_SMC_MM_RET_INVALID_PARAMS:
+	case ARM_SVC_SPM_RET_INVALID_PARAMS:
 		ret = EFI_INVALID_PARAMETER;
 		break;
 
-	case ARM_SMC_MM_RET_DENIED:
+	case ARM_SVC_SPM_RET_DENIED:
 		ret = EFI_ACCESS_DENIED;
 		break;
 
-	case ARM_SMC_MM_RET_NO_MEMORY:
+	case ARM_SVC_SPM_RET_NO_MEMORY:
 		ret = EFI_OUT_OF_RESOURCES;
 		break;