Re: [PATCH v11 2/9] tools: mkeficapsule: add firmware image signing

[AKASHI Takahiro <takahiro.akashi@linaro.org>]

Heinrich,

On Fri, Feb 11, 2022 at 08:16:34PM +0100, Heinrich Schuchardt wrote:
> On 2/9/22 11:10, AKASHI Takahiro wrote:
> > With this enhancement, mkeficapsule will be able to sign a capsule
> > file when it is created. A signature added will be used later
> > in the verification at FMP's SetImage() call.
> > 
> > To do that, we need specify additional command parameters:
> >    -monotonic-cout <count> : monotonic count
> >    -private-key <private key file> : private key file
> >    -certificate <certificate file> : certificate file
> > Only when all of those parameters are given, a signature will be added
> > to a capsule file.
> > 
> > Users are expected to maintain and increment the monotonic count at
> > every time of the update for each firmware image.
> > 
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > Reviewed-by: Simon Glass <sjg@chromium.org>
> > Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
> > ---
> >   .azure-pipelines.yml |   2 +-
> >   tools/Makefile       |   1 +
> >   tools/eficapsule.h   | 115 +++++++++++++
> >   tools/mkeficapsule.c | 380 +++++++++++++++++++++++++++++++++++++++----
> >   4 files changed, 463 insertions(+), 35 deletions(-)
> >   create mode 100644 tools/eficapsule.h
> > 
> > diff --git a/.azure-pipelines.yml b/.azure-pipelines.yml
> > index f2aa332be5cc..aecc9cb88441 100644
> > --- a/.azure-pipelines.yml
> > +++ b/.azure-pipelines.yml
> > @@ -25,7 +25,7 @@ stages:
> >             %CD:~0,2%\msys64\usr\bin\bash -lc "pacman --noconfirm -Syyuu"
> >           displayName: 'Update MSYS2'
> >         - script: |
> > -          %CD:~0,2%\msys64\usr\bin\bash -lc "pacman --noconfirm --needed -Sy make gcc bison flex diffutils openssl-devel"
> > +          %CD:~0,2%\msys64\usr\bin\bash -lc "pacman --noconfirm --needed -Sy make gcc bison flex diffutils openssl-devel libgnutls-devel"
> >           displayName: 'Install Toolchain'
> >         - script: |
> >             echo make tools-only_defconfig tools-only NO_SDL=1 > build-tools.sh
> > diff --git a/tools/Makefile b/tools/Makefile
> > index 766c0674f4a0..8da07d60a755 100644
> > --- a/tools/Makefile
> > +++ b/tools/Makefile
> > @@ -238,6 +238,7 @@ hostprogs-$(CONFIG_MIPS) += mips-relocs
> >   hostprogs-$(CONFIG_ASN1_COMPILER)	+= asn1_compiler
> >   HOSTCFLAGS_asn1_compiler.o = -idirafter $(srctree)/include
> > 
> > +HOSTLDLIBS_mkeficapsule += -lgnutls
> >   hostprogs-$(CONFIG_TOOLS_MKEFICAPSULE) += mkeficapsule
> > 
> >   # We build some files with extra pedantic flags to try to minimize things
> > diff --git a/tools/eficapsule.h b/tools/eficapsule.h
> > new file mode 100644
> > index 000000000000..8c1560bb0671
> > --- /dev/null
> > +++ b/tools/eficapsule.h
> > @@ -0,0 +1,115 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright 2021 Linaro Limited
> > + *		Author: AKASHI Takahiro
> > + *
> > + * derived from efi.h and efi_api.h to make the file POSIX-compliant
> > + */
> > +
> > +#ifndef _EFI_CAPSULE_H
> > +#define _EFI_CAPSULE_H
> > +
> > +#include <stdint.h>
> > +#include <pe.h> /* WIN_CERTIFICATE */
> > +
> > +/*
> > + * Gcc's predefined attributes are not recognized by clang.
> > + */
> > +#ifndef __packed
> > +#define __packed	__attribute__((__packed__))
> > +#endif
> > +
> > +#ifndef __aligned
> > +#define __aligned(x)	__attribute__((__aligned__(x)))
> > +#endif
> > +
> > +typedef struct {
> > +	uint8_t b[16];
> > +} efi_guid_t __aligned(8);
> > +
> > +#define EFI_GUID(a, b, c, d0, d1, d2, d3, d4, d5, d6, d7) \
> > +	{{ (a) & 0xff, ((a) >> 8) & 0xff, ((a) >> 16) & 0xff, \
> > +		((a) >> 24) & 0xff, \
> > +		(b) & 0xff, ((b) >> 8) & 0xff, \
> > +		(c) & 0xff, ((c) >> 8) & 0xff, \
> > +		(d0), (d1), (d2), (d3), (d4), (d5), (d6), (d7) } }
> > +
> > +#define EFI_FIRMWARE_MANAGEMENT_CAPSULE_ID_GUID \
> > +	EFI_GUID(0x6dcbd5ed, 0xe82d, 0x4c44, 0xbd, 0xa1, \
> > +		 0x71, 0x94, 0x19, 0x9a, 0xd9, 0x2a)
> > +
> > +#define EFI_FIRMWARE_IMAGE_TYPE_UBOOT_FIT_GUID \
> > +	EFI_GUID(0xae13ff2d, 0x9ad4, 0x4e25, 0x9a, 0xc8, \
> > +		 0x6d, 0x80, 0xb3, 0xb2, 0x21, 0x47)
> > +
> > +#define EFI_FIRMWARE_IMAGE_TYPE_UBOOT_RAW_GUID \
> > +	EFI_GUID(0xe2bb9c06, 0x70e9, 0x4b14, 0x97, 0xa3, \
> > +		 0x5a, 0x79, 0x13, 0x17, 0x6e, 0x3f)
> > +
> > +#define EFI_CERT_TYPE_PKCS7_GUID \
> > +	EFI_GUID(0x4aafd29d, 0x68df, 0x49ee, 0x8a, 0xa9, \
> > +		 0x34, 0x7d, 0x37, 0x56, 0x65, 0xa7)
> > +
> > +/* flags */
> > +#define CAPSULE_FLAGS_PERSIST_ACROSS_RESET      0x00010000
> > +
> > +struct efi_capsule_header {
> > +	efi_guid_t capsule_guid;
> > +	uint32_t header_size;
> > +	uint32_t flags;
> > +	uint32_t capsule_image_size;
> > +} __packed;
> > +
> > +struct efi_firmware_management_capsule_header {
> > +	uint32_t version;
> > +	uint16_t embedded_driver_count;
> > +	uint16_t payload_item_count;
> > +	uint32_t item_offset_list[];
> > +} __packed;
> > +
> > +/* image_capsule_support */
> > +#define CAPSULE_SUPPORT_AUTHENTICATION          0x0000000000000001
> > +
> > +struct efi_firmware_management_capsule_image_header {
> > +	uint32_t version;
> > +	efi_guid_t update_image_type_id;
> > +	uint8_t update_image_index;
> > +	uint8_t reserved[3];
> > +	uint32_t update_image_size;
> > +	uint32_t update_vendor_code_size;
> > +	uint64_t update_hardware_instance;
> > +	uint64_t image_capsule_support;
> > +} __packed;
> > +
> > +/**
> > + * win_certificate_uefi_guid - A certificate that encapsulates
> > + * a GUID-specific signature
> > + *
> > + * @hdr:	Windows certificate header
> > + * @cert_type:	Certificate type
> > + * @cert_data:	Certificate data
> > + */
> > +struct win_certificate_uefi_guid {
> > +	WIN_CERTIFICATE	hdr;
> > +	efi_guid_t cert_type;
> > +	uint8_t cert_data[];
> > +} __packed;
> > +
> > +/**
> > + * efi_firmware_image_authentication - Capsule authentication method
> > + * descriptor
> > + *
> > + * This structure describes an authentication information for
> > + * a capsule with IMAGE_ATTRIBUTE_AUTHENTICATION_REQUIRED set
> > + * and should be included as part of the capsule.
> > + * Only EFI_CERT_TYPE_PKCS7_GUID is accepted.
> > + *
> > + * @monotonic_count: Count to prevent replay
> > + * @auth_info: Authentication info
> > + */
> > +struct efi_firmware_image_authentication {
> > +	uint64_t monotonic_count;
> > +	struct win_certificate_uefi_guid auth_info;
> > +} __packed;
> > +
> > +#endif /* _EFI_CAPSULE_H */
> > diff --git a/tools/mkeficapsule.c b/tools/mkeficapsule.c
> > index 243fd6e48370..b996c66ad26a 100644
> > --- a/tools/mkeficapsule.c
> > +++ b/tools/mkeficapsule.c
> > @@ -16,21 +16,13 @@
> >   #include <sys/stat.h>
> >   #include <sys/types.h>
> > 
> > -typedef __u8 u8;
> > -typedef __u16 u16;
> > -typedef __u32 u32;
> > -typedef __u64 u64;
> > -typedef __s16 s16;
> > -typedef __s32 s32;
> > +#include <linux/kconfig.h>
> > 
> > -#define aligned_u64 __aligned_u64
> > +#include <gnutls/gnutls.h>
> > +#include <gnutls/pkcs7.h>
> > +#include <gnutls/abstract.h>
> > 
> > -#ifndef __packed
> > -#define __packed __attribute__((packed))
> > -#endif
> > -
> > -#include <efi.h>
> > -#include <efi_api.h>
> > +#include "eficapsule.h"
> > 
> >   static const char *tool_name = "mkeficapsule";
> > 
> > @@ -39,12 +31,19 @@ efi_guid_t efi_guid_image_type_uboot_fit =
> >   		EFI_FIRMWARE_IMAGE_TYPE_UBOOT_FIT_GUID;
> >   efi_guid_t efi_guid_image_type_uboot_raw =
> >   		EFI_FIRMWARE_IMAGE_TYPE_UBOOT_RAW_GUID;
> > +efi_guid_t efi_guid_cert_type_pkcs7 = EFI_CERT_TYPE_PKCS7_GUID;
> > +
> > +static const char *opts_short = "f:r:i:I:v:p:c:m:dh";
> > 
> >   static struct option options[] = {
> >   	{"fit", required_argument, NULL, 'f'},
> >   	{"raw", required_argument, NULL, 'r'},
> >   	{"index", required_argument, NULL, 'i'},
> >   	{"instance", required_argument, NULL, 'I'},
> > +	{"private-key", required_argument, NULL, 'p'},
> > +	{"certificate", required_argument, NULL, 'c'},
> > +	{"monotonic-count", required_argument, NULL, 'm'},
> > +	{"dump-sig", no_argument, NULL, 'd'},
> >   	{"help", no_argument, NULL, 'h'},
> >   	{NULL, 0, NULL, 0},
> >   };
> > @@ -58,10 +57,40 @@ static void print_usage(void)
> >   		"\t-r, --raw <raw image>       new raw image file\n"
> >   		"\t-i, --index <index>         update image index\n"
> >   		"\t-I, --instance <instance>   update hardware instance\n"
> > +		"\t-p, --private-key <privkey file>  private key file\n"
> > +		"\t-c, --certificate <cert file>     signer's certificate file\n"
> > +		"\t-m, --monotonic-count <count>     monotonic count\n"
> > +		"\t-d, --dump_sig              dump signature (*.p7)\n"
> >   		"\t-h, --help                  print a help message\n",
> >   		tool_name);
> >   }
> > 
> > +/**
> > + * auth_context - authentication context
> > + * @key_file:	Path to a private key file
> > + * @cert_file:	Path to a certificate file
> > + * @image_data:	Pointer to firmware data
> > + * @image_size:	Size of firmware data
> > + * @auth:	Authentication header
> > + * @sig_data:	Signature data
> > + * @sig_size:	Size of signature data
> > + *
> > + * Data structure used in create_auth_data(). @key_file through
> > + * @image_size are input parameters. @auth, @sig_data and @sig_size
> > + * are filled in by create_auth_data().
> > + */
> > +struct auth_context {
> > +	char *key_file;
> > +	char *cert_file;
> > +	uint8_t *image_data;
> > +	size_t image_size;
> > +	struct efi_firmware_image_authentication auth;
> > +	uint8_t *sig_data;
> > +	size_t sig_size;
> > +};
> > +
> > +static int dump_sig;
> > +
> >   /**
> >    * read_bin_file - read a firmware binary file
> >    * @bin:	Path to a firmware binary file
> > @@ -75,7 +104,7 @@ static void print_usage(void)
> >    * * 0  - on success
> >    * * -1 - on failure
> >    */
> > -static int read_bin_file(char *bin, void **data, off_t *bin_size)
> > +static int read_bin_file(char *bin, uint8_t **data, off_t *bin_size)
> >   {
> >   	FILE *g;
> >   	struct stat bin_stat;
> > @@ -147,6 +176,205 @@ static int write_capsule_file(FILE *f, void *data, size_t size, const char *msg)
> >   	return 0;
> >   }
> > 
> > +/**
> > + * create_auth_data - compose authentication data in capsule
> > + * @auth_context:	Pointer to authentication context
> > + *
> > + * Fill up an authentication header (.auth) and signature data (.sig_data)
> > + * in @auth_context, using library functions from openssl.
> > + * All the parameters in @auth_context must be filled in by a caller.
> > + *
> > + * Return:
> > + * * 0  - on success
> > + * * -1 - on failure
> > + */
> > +static int create_auth_data(struct auth_context *ctx)
> > +{
> > +	gnutls_datum_t cert;
> > +	gnutls_datum_t key;
> > +	off_t file_size;
> > +	gnutls_privkey_t pkey;
> > +	gnutls_x509_crt_t x509;
> > +	gnutls_pkcs7_t pkcs7;
> > +	gnutls_datum_t data;
> > +	gnutls_datum_t signature;
> > +	int ret;
> > +
> > +	ret = read_bin_file(ctx->cert_file, &cert.data, &file_size);
> > +	if (ret < 0)
> > +		return -1;
> > +	if (file_size > UINT_MAX)
> > +		return -1;
> > +	cert.size = file_size;
> > +
> > +	ret = read_bin_file(ctx->key_file, &key.data, &file_size);
> > +	if (ret < 0)
> > +		return -1;
> > +	if (ret < 0)
> > +		return -1;
> > +	if (file_size > UINT_MAX)
> > +		return -1;
> > +	key.size = file_size;
> > +
> > +	/*
> > +	 * For debugging,
> > +	 * gnutls_global_set_time_function(mytime);
> > +	 * gnutls_global_set_log_function(tls_log_func);
> > +	 * gnutls_global_set_log_level(6);
> > +	 */
> > +
> > +	ret = gnutls_privkey_init(&pkey);
> > +	if (ret < 0) {
> > +		fprintf(stderr, "error in gnutls_privkey_init(): %s\n",
> > +			gnutls_strerror(ret));
> > +		return -1;
> > +	}
> > +
> > +	ret = gnutls_x509_crt_init(&x509);
> > +	if (ret < 0) {
> > +		fprintf(stderr, "error in gnutls_x509_crt_init(): %s\n",
> > +			gnutls_strerror(ret));
> > +		return -1;
> > +	}
> > +
> > +	/* load a private key */
> > +	ret = gnutls_privkey_import_x509_raw(pkey, &key, GNUTLS_X509_FMT_PEM,
> > +					     0, 0);
> > +	if (ret < 0) {
> > +		fprintf(stderr,
> > +			"error in gnutls_privkey_import_x509_raw(): %s\n",
> > +			gnutls_strerror(ret));
> > +		return -1;
> > +	}
> > +
> > +	/* load x509 certificate */
> > +	ret = gnutls_x509_crt_import(x509, &cert, GNUTLS_X509_FMT_PEM);
> > +	if (ret < 0) {
> > +		fprintf(stderr, "error in gnutls_x509_crt_import(): %s\n",
> > +			gnutls_strerror(ret));
> > +		return -1;
> > +	}
> > +
> > +	/* generate a PKCS #7 structure */
> > +	ret = gnutls_pkcs7_init(&pkcs7);
> > +	if (ret < 0) {
> > +		fprintf(stderr, "error in gnutls_pkcs7_init(): %s\n",
> > +			gnutls_strerror(ret));
> > +		return -1;
> > +	}
> > +
> > +	/* sign */
> > +	/*
> > +	 * Data should have
> > +	 *  * firmware image
> > +	 *  * monotonic count
> > +	 * in this order!
> > +	 * See EDK2's FmpAuthenticatedHandlerRsa2048Sha256()
> > +	 */
> > +	data.size = ctx->image_size + sizeof(ctx->auth.monotonic_count);
> > +	data.data = malloc(data.size);
> > +	if (!data.data) {
> > +		fprintf(stderr, "allocating memory (0x%x) failed\n", data.size);
> > +		return -1;
> > +	}
> > +	memcpy(data.data, ctx->image_data, ctx->image_size);
> > +	memcpy(data.data + ctx->image_size, &ctx->auth.monotonic_count,
> > +	       sizeof(ctx->auth.monotonic_count));
> > +
> > +	ret = gnutls_pkcs7_sign(pkcs7, x509, pkey, &data, NULL, NULL,
> > +				GNUTLS_DIG_SHA256,
> > +				/* GNUTLS_PKCS7_EMBED_DATA? */
> > +				GNUTLS_PKCS7_INCLUDE_CERT |
> > +				GNUTLS_PKCS7_INCLUDE_TIME);
> > +	if (ret < 0) {
> > +		fprintf(stderr, "error in gnutls_pkcs7)sign(): %s\n",
> > +			gnutls_strerror(ret));
> > +		return -1;
> > +	}
> > +
> > +	/* export */
> > +	ret = gnutls_pkcs7_export2(pkcs7, GNUTLS_X509_FMT_DER, &signature);
> > +	if (ret < 0) {
> > +		fprintf(stderr, "error in gnutls_pkcs7_export2: %s\n",
> > +			gnutls_strerror(ret));
> > +		return -1;
> > +	}
> > +	ctx->sig_data = signature.data;
> > +	ctx->sig_size = signature.size;
> > +
> > +	/* fill auth_info */
> > +	ctx->auth.auth_info.hdr.dwLength = sizeof(ctx->auth.auth_info)
> > +						+ ctx->sig_size;
> > +	ctx->auth.auth_info.hdr.wRevision = WIN_CERT_REVISION_2_0;
> > +	ctx->auth.auth_info.hdr.wCertificateType = WIN_CERT_TYPE_EFI_GUID;
> > +	memcpy(&ctx->auth.auth_info.cert_type, &efi_guid_cert_type_pkcs7,
> > +	       sizeof(efi_guid_cert_type_pkcs7));
> > +
> > +	/*
> > +	 * For better clean-ups,
> > +	 * gnutls_pkcs7_deinit(pkcs7);
> > +	 * gnutls_privkey_deinit(pkey);
> > +	 * gnutls_x509_crt_deinit(x509);
> > +	 * free(cert.data);
> > +	 * free(key.data);
> > +	 * if error
> > +	 *   gnutls_free(signature.data);
> > +	 */
> > +
> > +	return 0;
> > +}
> > +
> > +/**
> > + * dump_signature - dump out a signature
> > + * @path:	Path to a capsule file
> > + * @signature:	Signature data
> > + * @sig_size:	Size of signature data
> > + *
> > + * Signature data pointed to by @signature will be saved into
> > + * a file whose file name is @path with ".p7" suffix.
> > + *
> > + * Return:
> > + * * 0  - on success
> > + * * -1 - on failure
> > + */
> > +static int dump_signature(const char *path, uint8_t *signature, size_t sig_size)
> > +{
> > +	char *sig_path;
> > +	FILE *f;
> > +	size_t size;
> > +	int ret = -1;
> > +
> > +	sig_path = malloc(strlen(path) + 3 + 1);
> > +	if (!sig_path)
> > +		return ret;
> > +
> > +	sprintf(sig_path, "%s.p7", path);
> > +	f = fopen(sig_path, "w");
> > +	if (!f)
> > +		goto err;
> > +
> > +	size = fwrite(signature, 1, sig_size, f);
> > +	if (size == sig_size)
> > +		ret = 0;
> > +
> > +	fclose(f);
> > +err:
> > +	free(sig_path);
> > +	return ret;
> > +}
> > +
> > +/**
> > + * free_sig_data - free out signature data
> > + * @ctx:	Pointer to authentication context
> > + *
> > + * Free signature data allocated in create_auth_data().
> > + */
> > +static void free_sig_data(struct auth_context *ctx)
> > +{
> > +	if (ctx->sig_size)
> > +		gnutls_free(ctx->sig_data);
> > +}
> > +
> >   /**
> >    * create_fwbin - create an uefi capsule file
> >    * @path:	Path to a created capsule file
> > @@ -168,23 +396,25 @@ static int write_capsule_file(FILE *f, void *data, size_t size, const char *msg)
> >    * * -1 - on failure
> >    */
> >   static int create_fwbin(char *path, char *bin, efi_guid_t *guid,
> > -			unsigned long index, unsigned long instance)
> > +			unsigned long index, unsigned long instance,
> > +			uint64_t mcount, char *privkey_file, char *cert_file)
> >   {
> >   	struct efi_capsule_header header;
> >   	struct efi_firmware_management_capsule_header capsule;
> >   	struct efi_firmware_management_capsule_image_header image;
> > +	struct auth_context auth_context;
> >   	FILE *f;
> > -	void *data;
> > +	uint8_t *data;
> >   	off_t bin_size;
> > -	u64 offset;
> > +	uint64_t offset;
> >   	int ret;
> > 
> >   #ifdef DEBUG
> > -	printf("For output: %s\n", path);
> > -	printf("\tbin: %s\n\ttype: %pUl\n", bin, guid);
> > -	printf("\tindex: %ld\n\tinstance: %ld\n", index, instance);
> > +	fprintf(stderr, "For output: %s\n", path);
> > +	fprintf(stderr, "\tbin: %s\n\ttype: %pUl\n", bin, guid);
> > +	fprintf(stderr, "\tindex: %lu\n\tinstance: %lu\n", index, instance);
> >   #endif
> > -
> > +	auth_context.sig_size = 0;
> >   	f = NULL;
> >   	data = NULL;
> >   	ret = -1;
> > @@ -195,6 +425,27 @@ static int create_fwbin(char *path, char *bin, efi_guid_t *guid,
> >   	if (read_bin_file(bin, &data, &bin_size))
> >   		goto err;
> > 
> > +	/* first, calculate signature to determine its size */
> > +	if (privkey_file && cert_file) {
> > +		auth_context.key_file = privkey_file;
> > +		auth_context.cert_file = cert_file;
> > +		auth_context.auth.monotonic_count = mcount;
> > +		auth_context.image_data = data;
> > +		auth_context.image_size = bin_size;
> > +
> > +		if (create_auth_data(&auth_context)) {
> > +			fprintf(stderr, "Signing firmware image failed\n");
> > +			goto err;
> > +		}
> > +
> > +		if (dump_sig &&
> > +		    dump_signature(path, auth_context.sig_data,
> > +				   auth_context.sig_size)) {
> > +			fprintf(stderr, "Creating signature file failed\n");
> > +			goto err;
> > +		}
> > +	}
> > +
> >   	/*
> >   	 * write a capsule file
> >   	 */
> > @@ -212,9 +463,12 @@ static int create_fwbin(char *path, char *bin, efi_guid_t *guid,
> >   	/* TODO: The current implementation ignores flags */
> >   	header.flags = CAPSULE_FLAGS_PERSIST_ACROSS_RESET;
> >   	header.capsule_image_size = sizeof(header)
> > -					+ sizeof(capsule) + sizeof(u64)
> > +					+ sizeof(capsule) + sizeof(uint64_t)
> >   					+ sizeof(image)
> >   					+ bin_size;
> > +	if (auth_context.sig_size)
> > +		header.capsule_image_size += sizeof(auth_context.auth)
> > +				+ auth_context.sig_size;
> >   	if (write_capsule_file(f, &header, sizeof(header),
> >   			       "Capsule header"))
> >   		goto err;
> > @@ -230,7 +484,7 @@ static int create_fwbin(char *path, char *bin, efi_guid_t *guid,
> >   			       "Firmware capsule header"))
> >   		goto err;
> > 
> > -	offset = sizeof(capsule) + sizeof(u64);
> > +	offset = sizeof(capsule) + sizeof(uint64_t);
> >   	if (write_capsule_file(f, &offset, sizeof(offset),
> >   			       "Offset to capsule image"))
> >   		goto err;
> > @@ -245,13 +499,32 @@ static int create_fwbin(char *path, char *bin, efi_guid_t *guid,
> >   	image.reserved[1] = 0;
> >   	image.reserved[2] = 0;
> >   	image.update_image_size = bin_size;
> > +	if (auth_context.sig_size)
> > +		image.update_image_size += sizeof(auth_context.auth)
> > +				+ auth_context.sig_size;
> >   	image.update_vendor_code_size = 0; /* none */
> >   	image.update_hardware_instance = instance;
> >   	image.image_capsule_support = 0;
> > +	if (auth_context.sig_size)
> > +		image.image_capsule_support |= CAPSULE_SUPPORT_AUTHENTICATION;
> >   	if (write_capsule_file(f, &image, sizeof(image),
> >   			       "Firmware capsule image header"))
> >   		goto err;
> > 
> > +	/*
> > +	 * signature
> > +	 */
> > +	if (auth_context.sig_size) {
> > +		if (write_capsule_file(f, &auth_context.auth,
> > +				       sizeof(auth_context.auth),
> > +				       "Authentication header"))
> > +			goto err;
> > +
> > +		if (write_capsule_file(f, auth_context.sig_data,
> > +				       auth_context.sig_size, "Signature"))
> > +			goto err;
> > +	}
> > +
> >   	/*
> >   	 * firmware binary
> >   	 */
> > @@ -262,28 +535,43 @@ static int create_fwbin(char *path, char *bin, efi_guid_t *guid,
> >   err:
> >   	if (f)
> >   		fclose(f);
> > +	free_sig_data(&auth_context);
> >   	free(data);
> > 
> >   	return ret;
> >   }
> > 
> > -/*
> > - * Usage:
> > - *   $ mkeficapsule -f <firmware binary> <output file>
> > +/**
> > + * main - main entry function of mkeficapsule
> > + * @argc:	Number of arguments
> > + * @argv:	Array of pointers to arguments
> > + *
> > + * Create an uefi capsule file, optionally signing it.
> > + * Parse all the arguments and pass them on to create_fwbin().
> > + *
> > + * Return:
> > + * * 0  - on success
> > + * * -1 - on failure
> >    */
> >   int main(int argc, char **argv)
> >   {
> >   	char *file;
> >   	efi_guid_t *guid;
> >   	unsigned long index, instance;
> > +	uint64_t mcount;
> > +	char *privkey_file, *cert_file;
> >   	int c, idx;
> > 
> >   	file = NULL;
> >   	guid = NULL;
> >   	index = 0;
> >   	instance = 0;
> > +	mcount = 0;
> > +	privkey_file = NULL;
> > +	cert_file = NULL;
> > +	dump_sig = 0;
> >   	for (;;) {
> > -		c = getopt_long(argc, argv, "f:r:i:I:v:h", options, &idx);
> > +		c = getopt_long(argc, argv, opts_short, options, &idx);
> >   		if (c == -1)
> >   			break;
> > 
> > @@ -291,7 +579,7 @@ int main(int argc, char **argv)
> >   		case 'f':
> >   			if (file) {
> >   				fprintf(stderr, "Image already specified\n");
> > -				return -1;
> > +				exit(EXIT_FAILURE);
> >   			}
> >   			file = optarg;
> >   			guid = &efi_guid_image_type_uboot_fit;
> > @@ -299,7 +587,7 @@ int main(int argc, char **argv)
> >   		case 'r':
> >   			if (file) {
> >   				fprintf(stderr, "Image already specified\n");
> > -				return -1;
> > +				exit(EXIT_FAILURE);
> >   			}
> >   			file = optarg;
> >   			guid = &efi_guid_image_type_uboot_raw;
> > @@ -310,14 +598,38 @@ int main(int argc, char **argv)
> >   		case 'I':
> >   			instance = strtoul(optarg, NULL, 0);
> >   			break;
> > +		case 'p':
> > +			if (privkey_file) {
> > +				fprintf(stderr,
> > +					"Private Key already specified\n");
> > +				exit(EXIT_FAILURE);
> > +			}
> > +			privkey_file = optarg;
> > +			break;
> > +		case 'c':
> > +			if (cert_file) {
> > +				fprintf(stderr,
> > +					"Certificate file already specified\n");
> > +				exit(EXIT_FAILURE);
> > +			}
> > +			cert_file = optarg;
> > +			break;
> > +		case 'm':
> > +			mcount = strtoul(optarg, NULL, 0);
> > +			break;
> > +		case 'd':
> > +			dump_sig = 1;
> > +			break;
> >   		case 'h':
> >   			print_usage();
> > -			return 0;
> > +			exit(EXIT_SUCCESS);
> >   		}
> >   	}
> > 
> > -	/* need an output file */
> > -	if (argc != optind + 1) {
> > +	/* check necessary parameters */
> > +	if ((argc != optind + 1) || !file ||
> > +	    ((privkey_file && !cert_file) ||
> > +	     (!privkey_file && cert_file))) {
> >   		print_usage();
> >   		exit(EXIT_FAILURE);
> >   	}
> > @@ -328,8 +640,8 @@ int main(int argc, char **argv)
> >   		exit(EXIT_SUCCESS);
> >   	}
> > 
> > -	if (create_fwbin(argv[optind], file, guid, index, instance)
> > -			< 0) {
> > +	if (create_fwbin(argv[optind], file, guid, index, instance,
> > +			 mcount, privkey_file, cert_file) < 0) {
> >   		fprintf(stderr, "Creating firmware capsule failed\n");
> >   		exit(EXIT_FAILURE);
> >   	}
> 
> Tom just caught the following warnings when building sandobox_defconfig
> with clang. Unfortunately -Werror is not enabled for tools yet.
> 
> In file included from tools/mkeficapsule.c:24:
> ./tools/eficapsule.h:93:18: warning: field 'hdr' with variable sized
> type 'WIN_CERTIFICATE' (aka 'struct _WIN_CERTIFICATE') not at the end of
> a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end]
>         WIN_CERTIFICATE hdr;
>                         ^
> tools/mkeficapsule.c:88:43: warning: field 'auth' with variable sized
> type 'struct efi_firmware_image_authentication' not at the end of a
> struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end]
>         struct efi_firmware_image_authentication auth;
>                                                  ^
> 
> As the zero sized members are not referenced we can remove them. The
> following diff seems to fix the problem:

The fix itself is fine, but

"Zero-sized members" is a common practice in UEFI specification and
a number of instances can also be seen in include/efi_api.h.

If this kind of technique is an "error", we should fix the header files
in the first place.

-Takahiro Akashi


> 
> diff --git a/tools/eficapsule.h b/tools/eficapsule.h
> index 8c1560bb06..69c9c58c2f 100644
> --- a/tools/eficapsule.h
> +++ b/tools/eficapsule.h
> @@ -10,7 +10,6 @@
>  #define _EFI_CAPSULE_H
> 
>  #include <stdint.h>
> -#include <pe.h> /* WIN_CERTIFICATE */
> 
>  /*
>   * Gcc's predefined attributes are not recognized by clang.
> @@ -85,14 +84,16 @@ struct efi_firmware_management_capsule_image_header {
>   * win_certificate_uefi_guid - A certificate that encapsulates
>   * a GUID-specific signature
>   *
> - * @hdr:       Windows certificate header
> + * @hdr:       Windows certificate header, cf. WIN_CERTIFICATE
>   * @cert_type: Certificate type
> - * @cert_data: Certificate data
>   */
>  struct win_certificate_uefi_guid {
> -       WIN_CERTIFICATE hdr;
> +       struct {
> +               uint32_t dwLength;
> +               uint16_t wRevision;
> +               uint16_t wCertificateType;
> +       } hdr;
>         efi_guid_t cert_type;
> -       uint8_t cert_data[];
>  } __packed;
> 
>  /**
> diff --git a/tools/mkeficapsule.c b/tools/mkeficapsule.c
> index 550f5f88e3..f7590e482f 100644
> --- a/tools/mkeficapsule.c
> +++ b/tools/mkeficapsule.c
> @@ -5,6 +5,7 @@
>   */
> 
>  #include <getopt.h>
> +#include <pe.h>
>  #include <stdbool.h>
>  #include <stdint.h>
>  #include <stdio.h>
> 
> Best regards
> 
> Heinrich