1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 2016-20 Intel Corporation. */
13 #include <sys/types.h>
15 #include <openssl/err.h>
16 #include <openssl/pem.h>
21 * FIXME: OpenSSL 3.0 has deprecated some functions. For now just ignore
24 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
35 static void free_q1q2_ctx(struct q1q2_ctx *ctx)
37 BN_CTX_free(ctx->bn_ctx);
45 static bool alloc_q1q2_ctx(const uint8_t *s, const uint8_t *m,
48 ctx->bn_ctx = BN_CTX_new();
49 ctx->s = BN_bin2bn(s, SGX_MODULUS_SIZE, NULL);
50 ctx->m = BN_bin2bn(m, SGX_MODULUS_SIZE, NULL);
55 if (!ctx->bn_ctx || !ctx->s || !ctx->m || !ctx->q1 || !ctx->qr ||
64 static void reverse_bytes(void *data, int length)
80 static bool calc_q1q2(const uint8_t *s, const uint8_t *m, uint8_t *q1,
86 if (!alloc_q1q2_ctx(s, m, &ctx)) {
87 fprintf(stderr, "Not enough memory for Q1Q2 calculation\n");
91 if (!BN_mul(ctx.q1, ctx.s, ctx.s, ctx.bn_ctx))
94 if (!BN_div(ctx.q1, ctx.qr, ctx.q1, ctx.m, ctx.bn_ctx))
97 if (BN_num_bytes(ctx.q1) > SGX_MODULUS_SIZE) {
98 fprintf(stderr, "Too large Q1 %d bytes\n",
99 BN_num_bytes(ctx.q1));
103 if (!BN_mul(ctx.q2, ctx.s, ctx.qr, ctx.bn_ctx))
106 if (!BN_div(ctx.q2, NULL, ctx.q2, ctx.m, ctx.bn_ctx))
109 if (BN_num_bytes(ctx.q2) > SGX_MODULUS_SIZE) {
110 fprintf(stderr, "Too large Q2 %d bytes\n",
111 BN_num_bytes(ctx.q2));
115 len = BN_bn2bin(ctx.q1, q1);
116 reverse_bytes(q1, len);
117 len = BN_bn2bin(ctx.q2, q2);
118 reverse_bytes(q2, len);
127 struct sgx_sigstruct_payload {
128 struct sgx_sigstruct_header header;
129 struct sgx_sigstruct_body body;
132 static bool check_crypto_errors(void)
135 bool had_errors = false;
136 const char *filename;
141 if (ERR_peek_error() == 0)
145 err = ERR_get_error_line(&filename, &line);
146 ERR_error_string_n(err, str, sizeof(str));
147 fprintf(stderr, "crypto: %s: %s:%d\n", str, filename, line);
153 static inline const BIGNUM *get_modulus(RSA *key)
157 RSA_get0_key(key, &n, NULL, NULL);
161 static RSA *gen_sign_key(void)
163 unsigned long sign_key_length;
167 sign_key_length = (unsigned long)&sign_key_end -
168 (unsigned long)&sign_key;
170 bio = BIO_new_mem_buf(&sign_key, sign_key_length);
174 key = PEM_read_bio_RSAPrivateKey(bio, NULL, NULL, NULL);
181 MRECREATE = 0x0045544145524345,
182 MREADD = 0x0000000044444145,
183 MREEXTEND = 0x00444E4554584545,
186 static bool mrenclave_update(EVP_MD_CTX *ctx, const void *data)
188 if (!EVP_DigestUpdate(ctx, data, 64)) {
189 fprintf(stderr, "digest update failed\n");
196 static bool mrenclave_commit(EVP_MD_CTX *ctx, uint8_t *mrenclave)
200 if (!EVP_DigestFinal_ex(ctx, (unsigned char *)mrenclave, &size)) {
201 fprintf(stderr, "digest commit failed\n");
206 fprintf(stderr, "invalid digest size = %u\n", size);
215 uint32_t ssaframesize;
217 uint8_t reserved[44];
218 } __attribute__((__packed__));
221 static bool mrenclave_ecreate(EVP_MD_CTX *ctx, uint64_t blob_size)
223 struct mrecreate mrecreate;
226 for (encl_size = 0x1000; encl_size < blob_size; )
229 memset(&mrecreate, 0, sizeof(mrecreate));
230 mrecreate.tag = MRECREATE;
231 mrecreate.ssaframesize = 1;
232 mrecreate.size = encl_size;
234 if (!EVP_DigestInit_ex(ctx, EVP_sha256(), NULL))
237 return mrenclave_update(ctx, &mrecreate);
243 uint64_t flags; /* SECINFO flags */
244 uint8_t reserved[40];
245 } __attribute__((__packed__));
247 static bool mrenclave_eadd(EVP_MD_CTX *ctx, uint64_t offset, uint64_t flags)
249 struct mreadd mreadd;
251 memset(&mreadd, 0, sizeof(mreadd));
253 mreadd.offset = offset;
254 mreadd.flags = flags;
256 return mrenclave_update(ctx, &mreadd);
262 uint8_t reserved[48];
263 } __attribute__((__packed__));
265 static bool mrenclave_eextend(EVP_MD_CTX *ctx, uint64_t offset,
268 struct mreextend mreextend;
271 for (i = 0; i < 0x1000; i += 0x100) {
272 memset(&mreextend, 0, sizeof(mreextend));
273 mreextend.tag = MREEXTEND;
274 mreextend.offset = offset + i;
276 if (!mrenclave_update(ctx, &mreextend))
279 if (!mrenclave_update(ctx, &data[i + 0x00]))
282 if (!mrenclave_update(ctx, &data[i + 0x40]))
285 if (!mrenclave_update(ctx, &data[i + 0x80]))
288 if (!mrenclave_update(ctx, &data[i + 0xC0]))
295 static bool mrenclave_segment(EVP_MD_CTX *ctx, struct encl *encl,
296 struct encl_segment *seg)
298 uint64_t end = seg->size;
301 for (offset = 0; offset < end; offset += PAGE_SIZE) {
302 if (!mrenclave_eadd(ctx, seg->offset + offset, seg->flags))
306 if (!mrenclave_eextend(ctx, seg->offset + offset, seg->src + offset))
314 bool encl_measure(struct encl *encl)
316 uint64_t header1[2] = {0x000000E100000006, 0x0000000000010000};
317 uint64_t header2[2] = {0x0000006000000101, 0x0000000100000060};
318 struct sgx_sigstruct *sigstruct = &encl->sigstruct;
319 struct sgx_sigstruct_payload payload;
320 uint8_t digest[SHA256_DIGEST_LENGTH];
326 memset(sigstruct, 0, sizeof(*sigstruct));
328 sigstruct->header.header1[0] = header1[0];
329 sigstruct->header.header1[1] = header1[1];
330 sigstruct->header.header2[0] = header2[0];
331 sigstruct->header.header2[1] = header2[1];
332 sigstruct->exponent = 3;
333 sigstruct->body.attributes = SGX_ATTR_MODE64BIT;
334 sigstruct->body.xfrm = 3;
337 if (check_crypto_errors())
340 key = gen_sign_key();
342 ERR_print_errors_fp(stdout);
346 BN_bn2bin(get_modulus(key), sigstruct->modulus);
348 ctx = EVP_MD_CTX_create();
352 if (!mrenclave_ecreate(ctx, encl->src_size))
355 for (i = 0; i < encl->nr_segments; i++) {
356 struct encl_segment *seg = &encl->segment_tbl[i];
358 if (!mrenclave_segment(ctx, encl, seg))
362 if (!mrenclave_commit(ctx, sigstruct->body.mrenclave))
365 memcpy(&payload.header, &sigstruct->header, sizeof(sigstruct->header));
366 memcpy(&payload.body, &sigstruct->body, sizeof(sigstruct->body));
368 SHA256((unsigned char *)&payload, sizeof(payload), digest);
370 if (!RSA_sign(NID_sha256, digest, SHA256_DIGEST_LENGTH,
371 sigstruct->signature, &siglen, key))
374 if (!calc_q1q2(sigstruct->signature, sigstruct->modulus, sigstruct->q1,
379 reverse_bytes(sigstruct->signature, SGX_MODULUS_SIZE);
380 reverse_bytes(sigstruct->modulus, SGX_MODULUS_SIZE);
382 EVP_MD_CTX_destroy(ctx);
387 EVP_MD_CTX_destroy(ctx);