1 /*- 2 * Copyright (c) 2014 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Edward Tomasz Napierala under sponsorship 6 * from the FreeBSD Foundation. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD: head/usr.sbin/uefisign/uefisign.c 279315 2015-02-26 09:15:24Z trasz $"); 33 34 #include <sys/wait.h> 35 #include <assert.h> 36 #include <err.h> 37 #include <errno.h> 38 #include <stdio.h> 39 #include <string.h> 40 #include <unistd.h> 41 42 #include <openssl/conf.h> 43 #include <openssl/evp.h> 44 #include <openssl/err.h> 45 #include <openssl/pem.h> 46 #include <openssl/pkcs7.h> 47 48 #include "uefisign.h" 49 #include "magic.h" 50 51 static void 52 usage(void) 53 { 54 55 fprintf(stderr, "usage: uefisign -c cert -k key -o outfile [-v] file\n" 56 " uefisign -V [-c cert] [-v] file\n"); 57 exit(1); 58 } 59 60 static char * 61 checked_strdup(const char *s) 62 { 63 char *c; 64 65 c = strdup(s); 66 if (c == NULL) 67 err(1, "strdup"); 68 return (c); 69 } 70 71 FILE * 72 checked_fopen(const char *path, const char *mode) 73 { 74 FILE *fp; 75 76 assert(path != NULL); 77 78 fp = fopen(path, mode); 79 if (fp == NULL) 80 err(1, "%s", path); 81 return (fp); 82 } 83 84 void 85 send_chunk(const void *buf, size_t len, int pipefd) 86 { 87 ssize_t ret; 88 89 ret = write(pipefd, &len, sizeof(len)); 90 if (ret != sizeof(len)) 91 err(1, "write"); 92 ret = write(pipefd, buf, len); 93 if (ret != (ssize_t)len) 94 err(1, "write"); 95 } 96 97 void 98 receive_chunk(void **bufp, size_t *lenp, int pipefd) 99 { 100 ssize_t ret; 101 size_t len; 102 void *buf; 103 104 ret = read(pipefd, &len, sizeof(len)); 105 if (ret != sizeof(len)) 106 err(1, "read"); 107 108 buf = calloc(1, len); 109 if (buf == NULL) 110 err(1, "calloc"); 111 112 ret = read(pipefd, buf, len); 113 if (ret != (ssize_t)len) 114 err(1, "read"); 115 116 *bufp = buf; 117 *lenp = len; 118 } 119 120 static char * 121 bin2hex(const char *bin, size_t bin_len) 122 { 123 unsigned char *hex, *tmp, ch; 124 size_t hex_len; 125 size_t i; 126 127 hex_len = bin_len * 2 + 1; /* +1 for '\0'. */ 128 hex = malloc(hex_len); 129 if (hex == NULL) 130 err(1, "malloc"); 131 132 tmp = hex; 133 for (i = 0; i < bin_len; i++) { 134 ch = bin[i]; 135 tmp += sprintf(tmp, "%02x", ch); 136 } 137 138 return (hex); 139 } 140 141 /* 142 * We need to replace a standard chunk of PKCS7 signature with one mandated 143 * by Authenticode. Problem is, replacing it just like that and then calling 144 * PKCS7_final() would make OpenSSL segfault somewhere in PKCS7_dataFinal(). 145 * So, instead, we call PKCS7_dataInit(), then put our Authenticode-specific 146 * data into BIO it returned, then call PKCS7_dataFinal() - which now somehow 147 * does not panic - and _then_ we replace it in the signature. This technique 148 * was used in sbsigntool by Jeremy Kerr, and might have originated in 149 * osslsigncode. 150 */ 151 static void 152 magic(PKCS7 *pkcs7, const char *digest, size_t digest_len) 153 { 154 BIO *bio, *t_bio; 155 ASN1_TYPE *t; 156 ASN1_STRING *s; 157 CONF *cnf; 158 unsigned char *buf, *tmp; 159 char *digest_hex, *magic_conf, *str; 160 int len, nid, ok; 161 162 digest_hex = bin2hex(digest, digest_len); 163 164 /* 165 * Construct the SpcIndirectDataContent chunk. 166 */ 167 nid = OBJ_create("1.3.6.1.4.1.311.2.1.4", NULL, NULL); 168 169 asprintf(&magic_conf, magic_fmt, digest_hex); 170 if (magic_conf == NULL) 171 err(1, "asprintf"); 172 173 bio = BIO_new_mem_buf((void *)magic_conf, -1); 174 if (bio == NULL) { 175 ERR_print_errors_fp(stderr); 176 errx(1, "BIO_new_mem_buf(3) failed"); 177 } 178 179 cnf = NCONF_new(NULL); 180 if (cnf == NULL) { 181 ERR_print_errors_fp(stderr); 182 errx(1, "NCONF_new(3) failed"); 183 } 184 185 ok = NCONF_load_bio(cnf, bio, NULL); 186 if (ok == 0) { 187 ERR_print_errors_fp(stderr); 188 errx(1, "NCONF_load_bio(3) failed"); 189 } 190 191 str = NCONF_get_string(cnf, "default", "asn1"); 192 if (str == NULL) { 193 ERR_print_errors_fp(stderr); 194 errx(1, "NCONF_get_string(3) failed"); 195 } 196 197 t = ASN1_generate_nconf(str, cnf); 198 if (t == NULL) { 199 ERR_print_errors_fp(stderr); 200 errx(1, "ASN1_generate_nconf(3) failed"); 201 } 202 203 /* 204 * We now have our proprietary piece of ASN.1. Let's do 205 * the actual signing. 206 */ 207 len = i2d_ASN1_TYPE(t, NULL); 208 tmp = buf = calloc(1, len); 209 if (tmp == NULL) 210 err(1, "calloc"); 211 i2d_ASN1_TYPE(t, &tmp); 212 213 /* 214 * We now have contents of 't' stuffed into memory buffer 'buf'. 215 */ 216 tmp = NULL; 217 t = NULL; 218 219 t_bio = PKCS7_dataInit(pkcs7, NULL); 220 if (t_bio == NULL) { 221 ERR_print_errors_fp(stderr); 222 errx(1, "PKCS7_dataInit(3) failed"); 223 } 224 225 BIO_write(t_bio, buf + 2, len - 2); 226 227 ok = PKCS7_dataFinal(pkcs7, t_bio); 228 if (ok == 0) { 229 ERR_print_errors_fp(stderr); 230 errx(1, "PKCS7_dataFinal(3) failed"); 231 } 232 233 t = ASN1_TYPE_new(); 234 s = ASN1_STRING_new(); 235 ASN1_STRING_set(s, buf, len); 236 ASN1_TYPE_set(t, V_ASN1_SEQUENCE, s); 237 238 PKCS7_set0_type_other(pkcs7->d.sign->contents, nid, t); 239 } 240 241 static void 242 sign(X509 *cert, EVP_PKEY *key, int pipefd) 243 { 244 PKCS7 *pkcs7; 245 BIO *bio, *out; 246 const EVP_MD *md; 247 PKCS7_SIGNER_INFO *info; 248 void *digest, *signature; 249 size_t digest_len, signature_len; 250 int ok; 251 252 assert(cert != NULL); 253 assert(key != NULL); 254 255 receive_chunk(&digest, &digest_len, pipefd); 256 257 bio = BIO_new_mem_buf(digest, digest_len); 258 if (bio == NULL) { 259 ERR_print_errors_fp(stderr); 260 errx(1, "BIO_new_mem_buf(3) failed"); 261 } 262 263 pkcs7 = PKCS7_sign(NULL, NULL, NULL, bio, PKCS7_BINARY | PKCS7_PARTIAL); 264 if (pkcs7 == NULL) { 265 ERR_print_errors_fp(stderr); 266 errx(1, "PKCS7_sign(3) failed"); 267 } 268 269 md = EVP_get_digestbyname(DIGEST); 270 if (md == NULL) { 271 ERR_print_errors_fp(stderr); 272 errx(1, "EVP_get_digestbyname(\"%s\") failed", DIGEST); 273 } 274 275 info = PKCS7_sign_add_signer(pkcs7, cert, key, md, 0); 276 if (info == NULL) { 277 ERR_print_errors_fp(stderr); 278 errx(1, "PKCS7_sign_add_signer(3) failed"); 279 } 280 281 /* 282 * XXX: All the signed binaries seem to have this, but where is it 283 * described in the spec? 284 */ 285 PKCS7_add_signed_attribute(info, NID_pkcs9_contentType, 286 V_ASN1_OBJECT, OBJ_txt2obj("1.3.6.1.4.1.311.2.1.4", 1)); 287 288 magic(pkcs7, digest, digest_len); 289 290 #if 0 291 out = BIO_new(BIO_s_file()); 292 BIO_set_fp(out, stdout, BIO_NOCLOSE); 293 PKCS7_print_ctx(out, pkcs7, 0, NULL); 294 295 i2d_PKCS7_bio(out, pkcs7); 296 #endif 297 298 out = BIO_new(BIO_s_mem()); 299 if (out == NULL) { 300 ERR_print_errors_fp(stderr); 301 errx(1, "BIO_new(3) failed"); 302 } 303 304 ok = i2d_PKCS7_bio(out, pkcs7); 305 if (ok == 0) { 306 ERR_print_errors_fp(stderr); 307 errx(1, "i2d_PKCS7_bio(3) failed"); 308 } 309 310 signature_len = BIO_get_mem_data(out, &signature); 311 if (signature_len <= 0) { 312 ERR_print_errors_fp(stderr); 313 errx(1, "BIO_get_mem_data(3) failed"); 314 } 315 316 (void)BIO_set_close(out, BIO_NOCLOSE); 317 BIO_free(out); 318 319 send_chunk(signature, signature_len, pipefd); 320 } 321 322 static int 323 wait_for_child(pid_t pid) 324 { 325 int status; 326 327 pid = waitpid(pid, &status, 0); 328 if (pid == -1) 329 err(1, "waitpid"); 330 331 return (WEXITSTATUS(status)); 332 } 333 334 int 335 main(int argc, char **argv) 336 { 337 int ch, error; 338 bool Vflag = false, vflag = false; 339 const char *certpath = NULL, *keypath = NULL, *outpath = NULL, *inpath = NULL; 340 FILE *certfp = NULL, *keyfp = NULL; 341 X509 *cert = NULL; 342 EVP_PKEY *key = NULL; 343 pid_t pid; 344 int pipefds[2]; 345 346 while ((ch = getopt(argc, argv, "Vc:k:o:v")) != -1) { 347 switch (ch) { 348 case 'V': 349 Vflag = true; 350 break; 351 case 'c': 352 certpath = checked_strdup(optarg); 353 break; 354 case 'k': 355 keypath = checked_strdup(optarg); 356 break; 357 case 'o': 358 outpath = checked_strdup(optarg); 359 break; 360 case 'v': 361 vflag = true; 362 break; 363 default: 364 usage(); 365 } 366 } 367 368 argc -= optind; 369 argv += optind; 370 if (argc != 1) 371 usage(); 372 373 if (Vflag) { 374 if (certpath != NULL) 375 errx(1, "-V and -c are mutually exclusive"); 376 if (keypath != NULL) 377 errx(1, "-V and -k are mutually exclusive"); 378 if (outpath != NULL) 379 errx(1, "-V and -o are mutually exclusive"); 380 } else { 381 if (certpath == NULL) 382 errx(1, "-c option is mandatory"); 383 if (keypath == NULL) 384 errx(1, "-k option is mandatory"); 385 if (outpath == NULL) 386 errx(1, "-o option is mandatory"); 387 } 388 389 inpath = argv[0]; 390 391 OPENSSL_config(NULL); 392 ERR_load_crypto_strings(); 393 OpenSSL_add_all_algorithms(); 394 395 error = pipe(pipefds); 396 if (error != 0) 397 err(1, "pipe"); 398 399 pid = fork(); 400 if (pid < 0) 401 err(1, "fork"); 402 403 if (pid == 0) 404 return (child(inpath, outpath, pipefds[1], Vflag, vflag)); 405 406 if (!Vflag) { 407 certfp = checked_fopen(certpath, "r"); 408 cert = PEM_read_X509(certfp, NULL, NULL, NULL); 409 if (cert == NULL) { 410 ERR_print_errors_fp(stderr); 411 errx(1, "failed to load certificate from %s", certpath); 412 } 413 414 keyfp = checked_fopen(keypath, "r"); 415 key = PEM_read_PrivateKey(keyfp, NULL, NULL, NULL); 416 if (key == NULL) { 417 ERR_print_errors_fp(stderr); 418 errx(1, "failed to load private key from %s", keypath); 419 } 420 421 sign(cert, key, pipefds[0]); 422 } 423 424 return (wait_for_child(pid)); 425 } 426