1 /* $NetBSD: certs.c,v 1.4 2025/03/02 00:03:41 riastradh Exp $ */ 2 3 /* 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 14 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 16 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 19 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26 #include <sys/cdefs.h> 27 #ifndef lint 28 __RCSID("$NetBSD: certs.c,v 1.4 2025/03/02 00:03:41 riastradh Exp $"); 29 #endif /* not lint */ 30 31 #include <assert.h> 32 #include <stdbool.h> 33 #include <stdio.h> 34 #include <stdlib.h> 35 #include <sys/efiio.h> 36 37 #include "efiio.h" 38 #include "defs.h" 39 #include "certs.h" 40 41 /* 42 * See UEFI spec section 32.4 43 */ 44 45 #define EFI_CERT_SHA256_GUID \ 46 {0xc1c41626,0x504c,0x4092,0xac,0xa9,\ 47 {0x41,0xf9,0x36,0x93,0x43,0x28}} 48 49 #define EFI_CERT_RSA2048_GUID \ 50 {0x3c5766e8,0x269c,0x4e34,0xaa,0x14,\ 51 {0xed,0x77,0x6e,0x85,0xb3,0xb6}} 52 53 #define EFI_CERT_RSA2048_SHA256_GUID \ 54 {0xe2b36190,0x879b,0x4a3d,0xad,0x8d,\ 55 {0xf2,0xe7,0xbb,0xa3,0x27,0x84}} 56 57 #define EFI_CERT_SHA1_GUID \ 58 {0x826ca512,0xcf10,0x4ac9,0xb1,0x87,\ 59 {0xbe,0x01,0x49,0x66,0x31,0xbd}} 60 61 #define EFI_CERT_RSA2048_SHA1_GUID \ 62 {0x67f8444f,0x8743,0x48f1,0xa3,0x28,\ 63 {0x1e,0xaa,0xb8,0x73,0x60,0x80}} 64 65 #define EFI_CERT_X509_GUID \ 66 {0xa5c059a1,0x94e4,0x4aa7,0x87,0xb5,\ 67 {0xab,0x15,0x5c,0x2b,0xf0,0x72}} 68 69 #define EFI_CERT_SHA224_GUID \ 70 {0x0b6e5233,0xa65c,0x44c9,0x94,0x07,\ 71 {0xd9,0xab,0x83,0xbf,0xc8,0xbd}} 72 73 #define EFI_CERT_SHA384_GUID \ 74 {0xff3e5307,0x9fd0,0x48c9,0x85,0xf1,\ 75 {0x8a,0xd5,0x6c,0x70,0x1e,0x01}} 76 77 #define EFI_CERT_SHA512_GUID \ 78 {0x093e0fae,0xa6c4,0x4f50,0x9f,0x1b,\ 79 {0xd4,0x1e,0x2b,0x89,0xc1,0x9a}} 80 81 #define EFI_CERT_X509_SHA256_GUID \ 82 {0x3bd2a492,0x96c0,0x4079,0xb4,0x20,\ 83 {0xfc,0xf9,0x8e,0xf1,0x03,0xed}} 84 85 #define EFI_CERT_X509_SHA384_GUID \ 86 {0x7076876e,0x80c2,0x4ee6,0xaa,0xd2,\ 87 {0x28,0xb3,0x49,0xa6,0x86,0x5b}} 88 89 #define EFI_CERT_X509_SHA512_GUID \ 90 {0x446dbf63,0x2502,0x4cda,0xbc,0xfa,\ 91 {0x24,0x65,0xd2,0xb0,0xfe,0x9d}} 92 93 #define EFI_CERT_EXTERNAL_MANAGEMENT_GUID \ 94 {0x452e8ced,0xdfff,0x4b8c,0xae,0x01,\ 95 {0x51,0x18,0x86,0x2e,0x68,0x2c}} 96 97 #define EFI_CERT_GUIDS \ 98 _X(SHA256, sigfn0, 16 + 32) \ 99 _X(RSA2048, sigfn0, 16 + 256) \ 100 _X(RSA2048_SHA256, sigfn0, 16 + 256) \ 101 _X(SHA1, sigfn0, 16 + 20) \ 102 _X(RSA2048_SHA1, sigfn0, 16 + 256) \ 103 _X(X509, sigfn0, 0) \ 104 _X(SHA224, sigfn0, 16 + 28) \ 105 _X(SHA384, sigfn0, 16 + 48) \ 106 _X(SHA512, sigfn0, 16 + 64) \ 107 _X(X509_SHA256, sigfn256, 16 + 48) \ 108 _X(X509_SHA384, sigfn384, 16 + 64) \ 109 _X(X509_SHA512, sigfn512, 16 + 80) \ 110 _X(EXTERNAL_MANAGEMENT, sigfn1, 16 + 1) 111 112 #define EFI_CERT_GUID_UNKNOWN "unknown" 113 114 /************************************************************************/ 115 116 typedef uint8_t EFI_SHA256_HASH[32]; 117 typedef uint8_t EFI_SHA384_HASH[48]; 118 typedef uint8_t EFI_SHA512_HASH[64]; 119 120 typedef struct EFI_SIGNATURE_DAT { 121 uuid_t SignatureOwner; 122 uint8_t SignatureData[]; 123 } __packed EFI_SIGNATURE_DATA_t; 124 125 typedef struct EFI_SIGNATURE_LIST { 126 uuid_t SignatureType; 127 uint32_t SignatureListSize; 128 uint32_t SignatureHeaderSize; 129 uint32_t SignatureSize; 130 uint8_t SignatureListBody[]; 131 // uint8_t SignatureHeader[SignatureHeaderSize]; 132 // EFI_SIGNATURE_DATA Signatures[][SignatureSize]; 133 } __packed EFI_SIGNATURE_LIST_t; 134 135 typedef struct { 136 uint16_t Year; // 1900 - 9999 137 uint8_t Month; // 1 - 12 138 uint8_t Day; // 1 - 31 139 uint8_t Hour; // 0 - 23 140 uint8_t Minute; // 0 - 59 141 uint8_t Second; // 0 - 59 142 uint8_t Pad1; 143 uint32_t Nanosecond; // 0 - 999,999,999 144 int16_t TimeZone; // -1440 to 1440 or 2047 (0x7ff) 145 #define EFI_UNSPECIFIED_TIMEZONE 0x07FF 146 uint8_t Daylight; 147 #define EFI_TIME_ADJUST_DAYLIGHT 0x01 148 #define EFI_TIME_IN_DAYLIGHT 0x02 149 uint8_t Pad2; 150 } __packed EFI_TIME; 151 152 /************************************************************************/ 153 154 static char * 155 show_time(const EFI_TIME *et, int indent) 156 { 157 /* 158 * XXX: Deal with the Daylight flags! 159 */ 160 printf("%*s%u.%u.%u %u:%u:%u.%u", 161 indent, "", 162 et->Year, 163 et->Month, 164 et->Day, 165 et->Hour, 166 et->Minute, 167 et->Second, 168 et->Nanosecond); 169 if (et->TimeZone != EFI_UNSPECIFIED_TIMEZONE) { 170 printf(" (%d)", et->TimeZone); 171 } 172 printf("\n"); 173 174 return NULL; 175 } 176 177 /************************************************************************/ 178 179 static int 180 sigfn0(const void *vp, size_t sz, int indent) 181 { 182 const struct { 183 uuid_t uuid; 184 uint8_t data[]; 185 } __packed *s = vp; 186 187 printf("%*sOwner: ", indent, ""); 188 uuid_printf(&s->uuid); 189 printf("\n"); 190 show_data(s->data, sz, " "); 191 return 0; 192 } 193 194 static int 195 sigfn1(const void *vp, size_t sz, int indent) 196 { 197 const struct { 198 uuid_t uuid; 199 uint8_t zero; 200 } __packed *s = vp; 201 202 assert(sizeof(*s) == sizeof(s->uuid) + sz); 203 printf("%*sOwner: ", indent, ""); 204 uuid_printf(&s->uuid); 205 printf("\n"); 206 printf("%*szero: 0x%02x\n", indent, "", s->zero); 207 return 0; 208 } 209 210 static int 211 sigfn256(const void *vp, size_t sz, int indent) 212 { 213 const struct { 214 uuid_t uuid; 215 EFI_SHA256_HASH ToBeSignedHash; 216 EFI_TIME TimeOfRevocation; 217 } __packed *s = vp; 218 219 assert(sizeof(*s) == sizeof(s->uuid) + sz); 220 printf("%*sOwner: ", indent, ""); 221 uuid_printf(&s->uuid); 222 printf("\n"); 223 show_data((const void *)&s->ToBeSignedHash, sizeof(s->ToBeSignedHash), 224 " "); 225 printf("%*sTimeOfRevocation: ", indent, ""); 226 show_time(&s->TimeOfRevocation, indent); 227 return 0; 228 } 229 230 static int 231 sigfn384(const void *vp, size_t sz, int indent) 232 { 233 const struct { 234 uuid_t uuid; 235 EFI_SHA384_HASH ToBeSignedHash; 236 EFI_TIME TimeOfRevocation; 237 } __packed *s = vp; 238 239 assert(sizeof(*s) == sizeof(s->uuid) + sz); 240 printf("%*sOwner: ", indent, ""); 241 uuid_printf(&s->uuid); 242 printf("\n"); 243 show_data((const void *)&s->ToBeSignedHash, sizeof(s->ToBeSignedHash), 244 " "); 245 printf("%*sTimeOfRevocation: ", indent, ""); 246 show_time(&s->TimeOfRevocation, indent); 247 return 0; 248 } 249 250 static int 251 sigfn512(const void *vp, size_t sz, int indent) 252 { 253 const struct { 254 uuid_t uuid; 255 EFI_SHA512_HASH ToBeSignedHash; 256 EFI_TIME TimeOfRevocation; 257 } __packed *s = vp; 258 259 assert(sizeof(*s) == sizeof(s->uuid) + sz); 260 printf("%*sOwner: ", indent, ""); 261 uuid_printf(&s->uuid); 262 printf("\n"); 263 show_data((const void *)&s->ToBeSignedHash, sizeof(s->ToBeSignedHash), 264 " "); 265 printf("%*sTimeOfRevocation: ", indent, ""); 266 show_time(&s->TimeOfRevocation, indent); 267 return 0; 268 } 269 270 /************************************************************************/ 271 272 struct cert_tbl { 273 uuid_t guid; 274 const char *name; 275 int (*sigfn)(const void *, size_t, int); 276 size_t sigsz; 277 }; 278 279 static int 280 sortcmpfn(const void *a, const void *b) 281 { 282 const struct cert_tbl *p = a; 283 const struct cert_tbl *q = b; 284 285 return memcmp(&p->guid, &q->guid, sizeof(p->guid)); 286 } 287 288 static int 289 srchcmpfn(const void *a, const void *b) 290 { 291 const struct cert_tbl *q = b; 292 293 return memcmp(a, &q->guid, sizeof(q->guid)); 294 } 295 296 static struct cert_tbl * 297 get_cert_info(uuid_t *uuid) 298 { 299 static bool init_done = false; 300 static struct cert_tbl tbl[] = { 301 #define _X(c,f,s) { .guid = EFI_CERT_ ## c ## _GUID, .name = #c, \ 302 .sigfn = f, .sigsz = s, }, 303 EFI_CERT_GUIDS 304 #undef _X 305 }; 306 struct cert_tbl *tp; 307 308 if (!init_done) { 309 qsort(tbl, __arraycount(tbl), sizeof(*tbl), sortcmpfn); 310 init_done = true; 311 } 312 313 tp = bsearch(uuid, tbl, __arraycount(tbl), sizeof(*tbl), srchcmpfn); 314 if (tp == NULL) { 315 printf("unknown owner GUID: "); 316 uuid_printf(uuid); 317 printf("\n"); 318 } 319 return tp; 320 } 321 322 /************************************************************************/ 323 324 static inline const char * 325 cert_info_name(struct cert_tbl *tp) 326 { 327 328 return tp ? tp->name : EFI_CERT_GUID_UNKNOWN; 329 } 330 331 PUBLIC const char * 332 get_cert_name(uuid_t *uuid) 333 { 334 335 return cert_info_name(get_cert_info(uuid)); 336 } 337 338 static struct cert_tbl * 339 show_signature_list_header(EFI_SIGNATURE_LIST_t *lp, int indent) 340 { 341 struct cert_tbl *tp; 342 const char *name; 343 344 tp = get_cert_info(&lp->SignatureType); 345 name = cert_info_name(tp); 346 printf("%*sSigType: %s\n", indent, "", name); 347 printf("%*sListSize: %d (0x%x)\n", indent, "", 348 lp->SignatureListSize, lp->SignatureListSize); 349 printf("%*sHdrSize: %d (0x%x)\n", indent, "", 350 lp->SignatureHeaderSize, lp->SignatureHeaderSize); 351 printf("%*sSigSize: %d (0x%x)\n", indent, "", 352 lp->SignatureSize, lp->SignatureSize); 353 354 return tp; 355 } 356 357 static int 358 parse_signature_list(const uint8_t *bp, size_t sz, int indent) 359 { 360 union { 361 const uint8_t *bp; 362 EFI_SIGNATURE_LIST_t *lp; 363 } u; 364 struct cert_tbl *tp; 365 const uint8_t *endall, *endlist; 366 367 u.bp = bp; 368 endall = bp + sz; 369 while (u.bp < endall) { 370 tp = show_signature_list_header(u.lp, indent); 371 372 /* 373 * XXX: all the documented cases seem to have no 374 * signature header. 375 */ 376 if (u.lp->SignatureHeaderSize != 0) { 377 printf("expected zero SignatureHeaderSize: got %d\n", 378 u.lp->SignatureHeaderSize); 379 } 380 assert(u.lp->SignatureHeaderSize == 0); 381 382 /* 383 * Sanity check. 384 */ 385 if (tp && tp->sigsz && tp->sigsz != u.lp->SignatureSize) { 386 printf("expected signature size: %zu, got: %u\n", 387 tp->sigsz, u.lp->SignatureSize); 388 } 389 390 endlist = u.bp + u.lp->SignatureListSize; 391 for (uint8_t *sp = u.lp->SignatureListBody 392 + u.lp->SignatureHeaderSize; 393 sp < endlist; 394 sp += u.lp->SignatureSize) { 395 if (tp) 396 tp->sigfn(sp, u.lp->SignatureSize, 2); 397 else 398 sigfn0(sp, u.lp->SignatureSize, 2); 399 } 400 401 u.bp = endlist; 402 } 403 return 0; 404 } 405 406 PUBLIC int 407 show_cert_data(efi_var_t *v, bool dbg) 408 { 409 union { 410 const uint8_t *bp; 411 EFI_SIGNATURE_LIST_t *lp; 412 } u; 413 const uint8_t *end; 414 const char *name; 415 416 printf("%s: ", v->name); 417 418 u.bp = v->ev.data; 419 end = u.bp + v->ev.datasize; 420 for (;;) { 421 name = get_cert_name(&u.lp->SignatureType); 422 423 u.bp += u.lp->SignatureListSize; 424 if (u.bp < end) 425 printf("%s ", name); 426 else { 427 printf("%s\n", name); 428 break; 429 } 430 } 431 432 if (dbg) 433 parse_signature_list(v->ev.data, v->ev.datasize, 2); 434 435 return 0; 436 } 437