diff options
Diffstat (limited to 'tools/testing/selftests/sgx/sigstruct.c')
| -rw-r--r-- | tools/testing/selftests/sgx/sigstruct.c | 381 | 
1 files changed, 381 insertions, 0 deletions
| diff --git a/tools/testing/selftests/sgx/sigstruct.c b/tools/testing/selftests/sgx/sigstruct.c new file mode 100644 index 000000000000..dee7a3d6c5a5 --- /dev/null +++ b/tools/testing/selftests/sgx/sigstruct.c @@ -0,0 +1,381 @@ +// SPDX-License-Identifier: GPL-2.0 +/*  Copyright(c) 2016-20 Intel Corporation. */ + +#define _GNU_SOURCE +#include <assert.h> +#include <getopt.h> +#include <stdbool.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <unistd.h> +#include <openssl/err.h> +#include <openssl/pem.h> +#include "defines.h" +#include "main.h" + +struct q1q2_ctx { +	BN_CTX *bn_ctx; +	BIGNUM *m; +	BIGNUM *s; +	BIGNUM *q1; +	BIGNUM *qr; +	BIGNUM *q2; +}; + +static void free_q1q2_ctx(struct q1q2_ctx *ctx) +{ +	BN_CTX_free(ctx->bn_ctx); +	BN_free(ctx->m); +	BN_free(ctx->s); +	BN_free(ctx->q1); +	BN_free(ctx->qr); +	BN_free(ctx->q2); +} + +static bool alloc_q1q2_ctx(const uint8_t *s, const uint8_t *m, +			   struct q1q2_ctx *ctx) +{ +	ctx->bn_ctx = BN_CTX_new(); +	ctx->s = BN_bin2bn(s, SGX_MODULUS_SIZE, NULL); +	ctx->m = BN_bin2bn(m, SGX_MODULUS_SIZE, NULL); +	ctx->q1 = BN_new(); +	ctx->qr = BN_new(); +	ctx->q2 = BN_new(); + +	if (!ctx->bn_ctx || !ctx->s || !ctx->m || !ctx->q1 || !ctx->qr || +	    !ctx->q2) { +		free_q1q2_ctx(ctx); +		return false; +	} + +	return true; +} + +static bool calc_q1q2(const uint8_t *s, const uint8_t *m, uint8_t *q1, +		      uint8_t *q2) +{ +	struct q1q2_ctx ctx; + +	if (!alloc_q1q2_ctx(s, m, &ctx)) { +		fprintf(stderr, "Not enough memory for Q1Q2 calculation\n"); +		return false; +	} + +	if (!BN_mul(ctx.q1, ctx.s, ctx.s, ctx.bn_ctx)) +		goto out; + +	if (!BN_div(ctx.q1, ctx.qr, ctx.q1, ctx.m, ctx.bn_ctx)) +		goto out; + +	if (BN_num_bytes(ctx.q1) > SGX_MODULUS_SIZE) { +		fprintf(stderr, "Too large Q1 %d bytes\n", +			BN_num_bytes(ctx.q1)); +		goto out; +	} + +	if (!BN_mul(ctx.q2, ctx.s, ctx.qr, ctx.bn_ctx)) +		goto out; + +	if (!BN_div(ctx.q2, NULL, ctx.q2, ctx.m, ctx.bn_ctx)) +		goto out; + +	if (BN_num_bytes(ctx.q2) > SGX_MODULUS_SIZE) { +		fprintf(stderr, "Too large Q2 %d bytes\n", +			BN_num_bytes(ctx.q2)); +		goto out; +	} + +	BN_bn2bin(ctx.q1, q1); +	BN_bn2bin(ctx.q2, q2); + +	free_q1q2_ctx(&ctx); +	return true; +out: +	free_q1q2_ctx(&ctx); +	return false; +} + +struct sgx_sigstruct_payload { +	struct sgx_sigstruct_header header; +	struct sgx_sigstruct_body body; +}; + +static bool check_crypto_errors(void) +{ +	int err; +	bool had_errors = false; +	const char *filename; +	int line; +	char str[256]; + +	for ( ; ; ) { +		if (ERR_peek_error() == 0) +			break; + +		had_errors = true; +		err = ERR_get_error_line(&filename, &line); +		ERR_error_string_n(err, str, sizeof(str)); +		fprintf(stderr, "crypto: %s: %s:%d\n", str, filename, line); +	} + +	return had_errors; +} + +static inline const BIGNUM *get_modulus(RSA *key) +{ +	const BIGNUM *n; + +	RSA_get0_key(key, &n, NULL, NULL); +	return n; +} + +static RSA *gen_sign_key(void) +{ +	unsigned long sign_key_length; +	BIO *bio; +	RSA *key; + +	sign_key_length = (unsigned long)&sign_key_end - +			  (unsigned long)&sign_key; + +	bio = BIO_new_mem_buf(&sign_key, sign_key_length); +	if (!bio) +		return NULL; + +	key = PEM_read_bio_RSAPrivateKey(bio, NULL, NULL, NULL); +	BIO_free(bio); + +	return key; +} + +static void reverse_bytes(void *data, int length) +{ +	int i = 0; +	int j = length - 1; +	uint8_t temp; +	uint8_t *ptr = data; + +	while (i < j) { +		temp = ptr[i]; +		ptr[i] = ptr[j]; +		ptr[j] = temp; +		i++; +		j--; +	} +} + +enum mrtags { +	MRECREATE = 0x0045544145524345, +	MREADD = 0x0000000044444145, +	MREEXTEND = 0x00444E4554584545, +}; + +static bool mrenclave_update(EVP_MD_CTX *ctx, const void *data) +{ +	if (!EVP_DigestUpdate(ctx, data, 64)) { +		fprintf(stderr, "digest update failed\n"); +		return false; +	} + +	return true; +} + +static bool mrenclave_commit(EVP_MD_CTX *ctx, uint8_t *mrenclave) +{ +	unsigned int size; + +	if (!EVP_DigestFinal_ex(ctx, (unsigned char *)mrenclave, &size)) { +		fprintf(stderr, "digest commit failed\n"); +		return false; +	} + +	if (size != 32) { +		fprintf(stderr, "invalid digest size = %u\n", size); +		return false; +	} + +	return true; +} + +struct mrecreate { +	uint64_t tag; +	uint32_t ssaframesize; +	uint64_t size; +	uint8_t reserved[44]; +} __attribute__((__packed__)); + + +static bool mrenclave_ecreate(EVP_MD_CTX *ctx, uint64_t blob_size) +{ +	struct mrecreate mrecreate; +	uint64_t encl_size; + +	for (encl_size = 0x1000; encl_size < blob_size; ) +		encl_size <<= 1; + +	memset(&mrecreate, 0, sizeof(mrecreate)); +	mrecreate.tag = MRECREATE; +	mrecreate.ssaframesize = 1; +	mrecreate.size = encl_size; + +	if (!EVP_DigestInit_ex(ctx, EVP_sha256(), NULL)) +		return false; + +	return mrenclave_update(ctx, &mrecreate); +} + +struct mreadd { +	uint64_t tag; +	uint64_t offset; +	uint64_t flags; /* SECINFO flags */ +	uint8_t reserved[40]; +} __attribute__((__packed__)); + +static bool mrenclave_eadd(EVP_MD_CTX *ctx, uint64_t offset, uint64_t flags) +{ +	struct mreadd mreadd; + +	memset(&mreadd, 0, sizeof(mreadd)); +	mreadd.tag = MREADD; +	mreadd.offset = offset; +	mreadd.flags = flags; + +	return mrenclave_update(ctx, &mreadd); +} + +struct mreextend { +	uint64_t tag; +	uint64_t offset; +	uint8_t reserved[48]; +} __attribute__((__packed__)); + +static bool mrenclave_eextend(EVP_MD_CTX *ctx, uint64_t offset, +			      const uint8_t *data) +{ +	struct mreextend mreextend; +	int i; + +	for (i = 0; i < 0x1000; i += 0x100) { +		memset(&mreextend, 0, sizeof(mreextend)); +		mreextend.tag = MREEXTEND; +		mreextend.offset = offset + i; + +		if (!mrenclave_update(ctx, &mreextend)) +			return false; + +		if (!mrenclave_update(ctx, &data[i + 0x00])) +			return false; + +		if (!mrenclave_update(ctx, &data[i + 0x40])) +			return false; + +		if (!mrenclave_update(ctx, &data[i + 0x80])) +			return false; + +		if (!mrenclave_update(ctx, &data[i + 0xC0])) +			return false; +	} + +	return true; +} + +static bool mrenclave_segment(EVP_MD_CTX *ctx, struct encl *encl, +			      struct encl_segment *seg) +{ +	uint64_t end = seg->offset + seg->size; +	uint64_t offset; + +	for (offset = seg->offset; offset < end; offset += PAGE_SIZE) { +		if (!mrenclave_eadd(ctx, offset, seg->flags)) +			return false; + +		if (!mrenclave_eextend(ctx, offset, encl->src + offset)) +			return false; +	} + +	return true; +} + +bool encl_measure(struct encl *encl) +{ +	uint64_t header1[2] = {0x000000E100000006, 0x0000000000010000}; +	uint64_t header2[2] = {0x0000006000000101, 0x0000000100000060}; +	struct sgx_sigstruct *sigstruct = &encl->sigstruct; +	struct sgx_sigstruct_payload payload; +	uint8_t digest[SHA256_DIGEST_LENGTH]; +	unsigned int siglen; +	RSA *key = NULL; +	EVP_MD_CTX *ctx; +	int i; + +	memset(sigstruct, 0, sizeof(*sigstruct)); + +	sigstruct->header.header1[0] = header1[0]; +	sigstruct->header.header1[1] = header1[1]; +	sigstruct->header.header2[0] = header2[0]; +	sigstruct->header.header2[1] = header2[1]; +	sigstruct->exponent = 3; +	sigstruct->body.attributes = SGX_ATTR_MODE64BIT; +	sigstruct->body.xfrm = 3; + +	/* sanity check */ +	if (check_crypto_errors()) +		goto err; + +	key = gen_sign_key(); +	if (!key) { +		ERR_print_errors_fp(stdout); +		goto err; +	} + +	BN_bn2bin(get_modulus(key), sigstruct->modulus); + +	ctx = EVP_MD_CTX_create(); +	if (!ctx) +		goto err; + +	if (!mrenclave_ecreate(ctx, encl->src_size)) +		goto err; + +	for (i = 0; i < encl->nr_segments; i++) { +		struct encl_segment *seg = &encl->segment_tbl[i]; + +		if (!mrenclave_segment(ctx, encl, seg)) +			goto err; +	} + +	if (!mrenclave_commit(ctx, sigstruct->body.mrenclave)) +		goto err; + +	memcpy(&payload.header, &sigstruct->header, sizeof(sigstruct->header)); +	memcpy(&payload.body, &sigstruct->body, sizeof(sigstruct->body)); + +	SHA256((unsigned char *)&payload, sizeof(payload), digest); + +	if (!RSA_sign(NID_sha256, digest, SHA256_DIGEST_LENGTH, +		      sigstruct->signature, &siglen, key)) +		goto err; + +	if (!calc_q1q2(sigstruct->signature, sigstruct->modulus, sigstruct->q1, +		       sigstruct->q2)) +		goto err; + +	/* BE -> LE */ +	reverse_bytes(sigstruct->signature, SGX_MODULUS_SIZE); +	reverse_bytes(sigstruct->modulus, SGX_MODULUS_SIZE); +	reverse_bytes(sigstruct->q1, SGX_MODULUS_SIZE); +	reverse_bytes(sigstruct->q2, SGX_MODULUS_SIZE); + +	EVP_MD_CTX_destroy(ctx); +	RSA_free(key); +	return true; + +err: +	EVP_MD_CTX_destroy(ctx); +	RSA_free(key); +	return false; +} | 
