1 // SPDX-License-Identifier: GPL-2.0 2 #include <test_progs.h> 3 #include <io_uring/mini_liburing.h> 4 #include "cgroup_helpers.h" 5 6 static char bpf_log_buf[4096]; 7 static bool verbose; 8 9 #ifndef PAGE_SIZE 10 #define PAGE_SIZE 4096 11 #endif 12 13 enum sockopt_test_error { 14 OK = 0, 15 DENY_LOAD, 16 DENY_ATTACH, 17 EOPNOTSUPP_GETSOCKOPT, 18 EPERM_GETSOCKOPT, 19 EFAULT_GETSOCKOPT, 20 EPERM_SETSOCKOPT, 21 EFAULT_SETSOCKOPT, 22 }; 23 24 static struct sockopt_test { 25 const char *descr; 26 const struct bpf_insn insns[64]; 27 enum bpf_attach_type attach_type; 28 enum bpf_attach_type expected_attach_type; 29 30 int set_optname; 31 int set_level; 32 const char set_optval[64]; 33 socklen_t set_optlen; 34 35 int get_optname; 36 int get_level; 37 const char get_optval[64]; 38 socklen_t get_optlen; 39 socklen_t get_optlen_ret; 40 41 enum sockopt_test_error error; 42 bool io_uring_support; 43 } tests[] = { 44 45 /* ==================== getsockopt ==================== */ 46 47 { 48 .descr = "getsockopt: no expected_attach_type", 49 .insns = { 50 /* return 1 */ 51 BPF_MOV64_IMM(BPF_REG_0, 1), 52 BPF_EXIT_INSN(), 53 54 }, 55 .attach_type = BPF_CGROUP_GETSOCKOPT, 56 .expected_attach_type = 0, 57 .error = DENY_LOAD, 58 }, 59 { 60 .descr = "getsockopt: wrong expected_attach_type", 61 .insns = { 62 /* return 1 */ 63 BPF_MOV64_IMM(BPF_REG_0, 1), 64 BPF_EXIT_INSN(), 65 66 }, 67 .attach_type = BPF_CGROUP_GETSOCKOPT, 68 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 69 .error = DENY_ATTACH, 70 }, 71 { 72 .descr = "getsockopt: bypass bpf hook", 73 .insns = { 74 /* return 1 */ 75 BPF_MOV64_IMM(BPF_REG_0, 1), 76 BPF_EXIT_INSN(), 77 }, 78 .attach_type = BPF_CGROUP_GETSOCKOPT, 79 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 80 81 .get_level = SOL_IP, 82 .set_level = SOL_IP, 83 84 .get_optname = IP_TOS, 85 .set_optname = IP_TOS, 86 87 .set_optval = { 1 << 3 }, 88 .set_optlen = 1, 89 90 .get_optval = { 1 << 3 }, 91 .get_optlen = 1, 92 }, 93 { 94 .descr = "getsockopt: return EPERM from bpf hook", 95 .insns = { 96 BPF_MOV64_IMM(BPF_REG_0, 0), 97 BPF_EXIT_INSN(), 98 }, 99 .attach_type = BPF_CGROUP_GETSOCKOPT, 100 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 101 102 .get_level = SOL_IP, 103 .get_optname = IP_TOS, 104 105 .get_optlen = 1, 106 .error = EPERM_GETSOCKOPT, 107 }, 108 { 109 .descr = "getsockopt: no optval bounds check, deny loading", 110 .insns = { 111 /* r6 = ctx->optval */ 112 BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 113 offsetof(struct bpf_sockopt, optval)), 114 115 /* ctx->optval[0] = 0x80 */ 116 BPF_MOV64_IMM(BPF_REG_0, 0x80), 117 BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_0, 0), 118 119 /* return 1 */ 120 BPF_MOV64_IMM(BPF_REG_0, 1), 121 BPF_EXIT_INSN(), 122 }, 123 .attach_type = BPF_CGROUP_GETSOCKOPT, 124 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 125 .error = DENY_LOAD, 126 }, 127 { 128 .descr = "getsockopt: read ctx->level", 129 .insns = { 130 /* r6 = ctx->level */ 131 BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1, 132 offsetof(struct bpf_sockopt, level)), 133 134 /* if (ctx->level == 123) { */ 135 BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 123, 4), 136 /* ctx->retval = 0 */ 137 BPF_MOV64_IMM(BPF_REG_0, 0), 138 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 139 offsetof(struct bpf_sockopt, retval)), 140 /* return 1 */ 141 BPF_MOV64_IMM(BPF_REG_0, 1), 142 BPF_JMP_A(1), 143 /* } else { */ 144 /* return 0 */ 145 BPF_MOV64_IMM(BPF_REG_0, 0), 146 /* } */ 147 BPF_EXIT_INSN(), 148 }, 149 .attach_type = BPF_CGROUP_GETSOCKOPT, 150 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 151 152 .get_level = 123, 153 154 .get_optlen = 1, 155 }, 156 { 157 .descr = "getsockopt: deny writing to ctx->level", 158 .insns = { 159 /* ctx->level = 1 */ 160 BPF_MOV64_IMM(BPF_REG_0, 1), 161 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 162 offsetof(struct bpf_sockopt, level)), 163 BPF_EXIT_INSN(), 164 }, 165 .attach_type = BPF_CGROUP_GETSOCKOPT, 166 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 167 168 .error = DENY_LOAD, 169 }, 170 { 171 .descr = "getsockopt: read ctx->optname", 172 .insns = { 173 /* r6 = ctx->optname */ 174 BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1, 175 offsetof(struct bpf_sockopt, optname)), 176 177 /* if (ctx->optname == 123) { */ 178 BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 123, 4), 179 /* ctx->retval = 0 */ 180 BPF_MOV64_IMM(BPF_REG_0, 0), 181 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 182 offsetof(struct bpf_sockopt, retval)), 183 /* return 1 */ 184 BPF_MOV64_IMM(BPF_REG_0, 1), 185 BPF_JMP_A(1), 186 /* } else { */ 187 /* return 0 */ 188 BPF_MOV64_IMM(BPF_REG_0, 0), 189 /* } */ 190 BPF_EXIT_INSN(), 191 }, 192 .attach_type = BPF_CGROUP_GETSOCKOPT, 193 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 194 195 .get_optname = 123, 196 197 .get_optlen = 1, 198 }, 199 { 200 .descr = "getsockopt: read ctx->retval", 201 .insns = { 202 /* r6 = ctx->retval */ 203 BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1, 204 offsetof(struct bpf_sockopt, retval)), 205 206 /* return 1 */ 207 BPF_MOV64_IMM(BPF_REG_0, 1), 208 BPF_EXIT_INSN(), 209 }, 210 .attach_type = BPF_CGROUP_GETSOCKOPT, 211 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 212 213 .get_level = SOL_IP, 214 .get_optname = IP_TOS, 215 .get_optlen = 1, 216 }, 217 { 218 .descr = "getsockopt: deny writing to ctx->optname", 219 .insns = { 220 /* ctx->optname = 1 */ 221 BPF_MOV64_IMM(BPF_REG_0, 1), 222 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 223 offsetof(struct bpf_sockopt, optname)), 224 BPF_EXIT_INSN(), 225 }, 226 .attach_type = BPF_CGROUP_GETSOCKOPT, 227 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 228 229 .error = DENY_LOAD, 230 }, 231 { 232 .descr = "getsockopt: read ctx->optlen", 233 .insns = { 234 /* r6 = ctx->optlen */ 235 BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1, 236 offsetof(struct bpf_sockopt, optlen)), 237 238 /* if (ctx->optlen == 64) { */ 239 BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 64, 4), 240 /* ctx->retval = 0 */ 241 BPF_MOV64_IMM(BPF_REG_0, 0), 242 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 243 offsetof(struct bpf_sockopt, retval)), 244 /* return 1 */ 245 BPF_MOV64_IMM(BPF_REG_0, 1), 246 BPF_JMP_A(1), 247 /* } else { */ 248 /* return 0 */ 249 BPF_MOV64_IMM(BPF_REG_0, 0), 250 /* } */ 251 BPF_EXIT_INSN(), 252 }, 253 .attach_type = BPF_CGROUP_GETSOCKOPT, 254 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 255 256 .get_level = SOL_SOCKET, 257 .get_optlen = 64, 258 .io_uring_support = true, 259 }, 260 { 261 .descr = "getsockopt: deny bigger ctx->optlen", 262 .insns = { 263 /* ctx->optlen = 65 */ 264 BPF_MOV64_IMM(BPF_REG_0, 65), 265 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 266 offsetof(struct bpf_sockopt, optlen)), 267 268 /* ctx->retval = 0 */ 269 BPF_MOV64_IMM(BPF_REG_0, 0), 270 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 271 offsetof(struct bpf_sockopt, retval)), 272 273 /* return 1 */ 274 BPF_MOV64_IMM(BPF_REG_0, 1), 275 BPF_EXIT_INSN(), 276 }, 277 .attach_type = BPF_CGROUP_GETSOCKOPT, 278 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 279 280 .get_optlen = 64, 281 282 .error = EFAULT_GETSOCKOPT, 283 .io_uring_support = true, 284 }, 285 { 286 .descr = "getsockopt: ignore >PAGE_SIZE optlen", 287 .insns = { 288 /* write 0xFF to the first optval byte */ 289 290 /* r6 = ctx->optval */ 291 BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 292 offsetof(struct bpf_sockopt, optval)), 293 /* r2 = ctx->optval */ 294 BPF_MOV64_REG(BPF_REG_2, BPF_REG_6), 295 /* r6 = ctx->optval + 1 */ 296 BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 1), 297 298 /* r7 = ctx->optval_end */ 299 BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_1, 300 offsetof(struct bpf_sockopt, optval_end)), 301 302 /* if (ctx->optval + 1 <= ctx->optval_end) { */ 303 BPF_JMP_REG(BPF_JGT, BPF_REG_6, BPF_REG_7, 1), 304 /* ctx->optval[0] = 0xF0 */ 305 BPF_ST_MEM(BPF_B, BPF_REG_2, 0, 0xFF), 306 /* } */ 307 308 /* retval changes are ignored */ 309 /* ctx->retval = 5 */ 310 BPF_MOV64_IMM(BPF_REG_0, 5), 311 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 312 offsetof(struct bpf_sockopt, retval)), 313 314 /* return 1 */ 315 BPF_MOV64_IMM(BPF_REG_0, 1), 316 BPF_EXIT_INSN(), 317 }, 318 .attach_type = BPF_CGROUP_GETSOCKOPT, 319 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 320 321 .get_level = 1234, 322 .get_optname = 5678, 323 .get_optval = {}, /* the changes are ignored */ 324 .get_optlen = PAGE_SIZE + 1, 325 .error = EOPNOTSUPP_GETSOCKOPT, 326 .io_uring_support = true, 327 }, 328 { 329 .descr = "getsockopt: support smaller ctx->optlen", 330 .insns = { 331 /* ctx->optlen = 32 */ 332 BPF_MOV64_IMM(BPF_REG_0, 32), 333 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 334 offsetof(struct bpf_sockopt, optlen)), 335 /* ctx->retval = 0 */ 336 BPF_MOV64_IMM(BPF_REG_0, 0), 337 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 338 offsetof(struct bpf_sockopt, retval)), 339 /* return 1 */ 340 BPF_MOV64_IMM(BPF_REG_0, 1), 341 BPF_EXIT_INSN(), 342 }, 343 .attach_type = BPF_CGROUP_GETSOCKOPT, 344 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 345 346 .get_level = SOL_SOCKET, 347 .get_optlen = 64, 348 .get_optlen_ret = 32, 349 .io_uring_support = true, 350 }, 351 { 352 .descr = "getsockopt: deny writing to ctx->optval", 353 .insns = { 354 /* ctx->optval = 1 */ 355 BPF_MOV64_IMM(BPF_REG_0, 1), 356 BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 357 offsetof(struct bpf_sockopt, optval)), 358 BPF_EXIT_INSN(), 359 }, 360 .attach_type = BPF_CGROUP_GETSOCKOPT, 361 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 362 363 .error = DENY_LOAD, 364 }, 365 { 366 .descr = "getsockopt: deny writing to ctx->optval_end", 367 .insns = { 368 /* ctx->optval_end = 1 */ 369 BPF_MOV64_IMM(BPF_REG_0, 1), 370 BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 371 offsetof(struct bpf_sockopt, optval_end)), 372 BPF_EXIT_INSN(), 373 }, 374 .attach_type = BPF_CGROUP_GETSOCKOPT, 375 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 376 377 .error = DENY_LOAD, 378 }, 379 { 380 .descr = "getsockopt: rewrite value", 381 .insns = { 382 /* r6 = ctx->optval */ 383 BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 384 offsetof(struct bpf_sockopt, optval)), 385 /* r2 = ctx->optval */ 386 BPF_MOV64_REG(BPF_REG_2, BPF_REG_6), 387 /* r6 = ctx->optval + 1 */ 388 BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 1), 389 390 /* r7 = ctx->optval_end */ 391 BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_1, 392 offsetof(struct bpf_sockopt, optval_end)), 393 394 /* if (ctx->optval + 1 <= ctx->optval_end) { */ 395 BPF_JMP_REG(BPF_JGT, BPF_REG_6, BPF_REG_7, 1), 396 /* ctx->optval[0] = 0xF0 */ 397 BPF_ST_MEM(BPF_B, BPF_REG_2, 0, 0xF0), 398 /* } */ 399 400 /* ctx->retval = 0 */ 401 BPF_MOV64_IMM(BPF_REG_0, 0), 402 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 403 offsetof(struct bpf_sockopt, retval)), 404 405 /* return 1*/ 406 BPF_MOV64_IMM(BPF_REG_0, 1), 407 BPF_EXIT_INSN(), 408 }, 409 .attach_type = BPF_CGROUP_GETSOCKOPT, 410 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 411 412 .get_level = SOL_IP, 413 .get_optname = IP_TOS, 414 415 .get_optval = { 0xF0 }, 416 .get_optlen = 1, 417 }, 418 419 /* ==================== setsockopt ==================== */ 420 421 { 422 .descr = "setsockopt: no expected_attach_type", 423 .insns = { 424 /* return 1 */ 425 BPF_MOV64_IMM(BPF_REG_0, 1), 426 BPF_EXIT_INSN(), 427 428 }, 429 .attach_type = BPF_CGROUP_SETSOCKOPT, 430 .expected_attach_type = 0, 431 .error = DENY_LOAD, 432 }, 433 { 434 .descr = "setsockopt: wrong expected_attach_type", 435 .insns = { 436 /* return 1 */ 437 BPF_MOV64_IMM(BPF_REG_0, 1), 438 BPF_EXIT_INSN(), 439 440 }, 441 .attach_type = BPF_CGROUP_SETSOCKOPT, 442 .expected_attach_type = BPF_CGROUP_GETSOCKOPT, 443 .error = DENY_ATTACH, 444 }, 445 { 446 .descr = "setsockopt: bypass bpf hook", 447 .insns = { 448 /* return 1 */ 449 BPF_MOV64_IMM(BPF_REG_0, 1), 450 BPF_EXIT_INSN(), 451 }, 452 .attach_type = BPF_CGROUP_SETSOCKOPT, 453 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 454 455 .get_level = SOL_IP, 456 .set_level = SOL_IP, 457 458 .get_optname = IP_TOS, 459 .set_optname = IP_TOS, 460 461 .set_optval = { 1 << 3 }, 462 .set_optlen = 1, 463 464 .get_optval = { 1 << 3 }, 465 .get_optlen = 1, 466 }, 467 { 468 .descr = "setsockopt: return EPERM from bpf hook", 469 .insns = { 470 /* return 0 */ 471 BPF_MOV64_IMM(BPF_REG_0, 0), 472 BPF_EXIT_INSN(), 473 }, 474 .attach_type = BPF_CGROUP_SETSOCKOPT, 475 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 476 477 .set_level = SOL_IP, 478 .set_optname = IP_TOS, 479 480 .set_optlen = 1, 481 .error = EPERM_SETSOCKOPT, 482 }, 483 { 484 .descr = "setsockopt: no optval bounds check, deny loading", 485 .insns = { 486 /* r6 = ctx->optval */ 487 BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 488 offsetof(struct bpf_sockopt, optval)), 489 490 /* r0 = ctx->optval[0] */ 491 BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_6, 0), 492 493 /* return 1 */ 494 BPF_MOV64_IMM(BPF_REG_0, 1), 495 BPF_EXIT_INSN(), 496 }, 497 .attach_type = BPF_CGROUP_SETSOCKOPT, 498 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 499 .error = DENY_LOAD, 500 }, 501 { 502 .descr = "setsockopt: read ctx->level", 503 .insns = { 504 /* r6 = ctx->level */ 505 BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1, 506 offsetof(struct bpf_sockopt, level)), 507 508 /* if (ctx->level == 123) { */ 509 BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 123, 4), 510 /* ctx->optlen = -1 */ 511 BPF_MOV64_IMM(BPF_REG_0, -1), 512 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 513 offsetof(struct bpf_sockopt, optlen)), 514 /* return 1 */ 515 BPF_MOV64_IMM(BPF_REG_0, 1), 516 BPF_JMP_A(1), 517 /* } else { */ 518 /* return 0 */ 519 BPF_MOV64_IMM(BPF_REG_0, 0), 520 /* } */ 521 BPF_EXIT_INSN(), 522 }, 523 .attach_type = BPF_CGROUP_SETSOCKOPT, 524 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 525 526 .set_level = 123, 527 528 .set_optlen = 1, 529 .io_uring_support = true, 530 }, 531 { 532 .descr = "setsockopt: allow changing ctx->level", 533 .insns = { 534 /* ctx->level = SOL_IP */ 535 BPF_MOV64_IMM(BPF_REG_0, SOL_IP), 536 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 537 offsetof(struct bpf_sockopt, level)), 538 /* return 1 */ 539 BPF_MOV64_IMM(BPF_REG_0, 1), 540 BPF_EXIT_INSN(), 541 }, 542 .attach_type = BPF_CGROUP_SETSOCKOPT, 543 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 544 545 .get_level = SOL_IP, 546 .set_level = 234, /* should be rewritten to SOL_IP */ 547 548 .get_optname = IP_TOS, 549 .set_optname = IP_TOS, 550 551 .set_optval = { 1 << 3 }, 552 .set_optlen = 1, 553 .get_optval = { 1 << 3 }, 554 .get_optlen = 1, 555 }, 556 { 557 .descr = "setsockopt: read ctx->optname", 558 .insns = { 559 /* r6 = ctx->optname */ 560 BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1, 561 offsetof(struct bpf_sockopt, optname)), 562 563 /* if (ctx->optname == 123) { */ 564 BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 123, 4), 565 /* ctx->optlen = -1 */ 566 BPF_MOV64_IMM(BPF_REG_0, -1), 567 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 568 offsetof(struct bpf_sockopt, optlen)), 569 /* return 1 */ 570 BPF_MOV64_IMM(BPF_REG_0, 1), 571 BPF_JMP_A(1), 572 /* } else { */ 573 /* return 0 */ 574 BPF_MOV64_IMM(BPF_REG_0, 0), 575 /* } */ 576 BPF_EXIT_INSN(), 577 }, 578 .attach_type = BPF_CGROUP_SETSOCKOPT, 579 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 580 581 .set_optname = 123, 582 583 .set_optlen = 1, 584 .io_uring_support = true, 585 }, 586 { 587 .descr = "setsockopt: allow changing ctx->optname", 588 .insns = { 589 /* ctx->optname = IP_TOS */ 590 BPF_MOV64_IMM(BPF_REG_0, IP_TOS), 591 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 592 offsetof(struct bpf_sockopt, optname)), 593 /* return 1 */ 594 BPF_MOV64_IMM(BPF_REG_0, 1), 595 BPF_EXIT_INSN(), 596 }, 597 .attach_type = BPF_CGROUP_SETSOCKOPT, 598 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 599 600 .get_level = SOL_IP, 601 .set_level = SOL_IP, 602 603 .get_optname = IP_TOS, 604 .set_optname = 456, /* should be rewritten to IP_TOS */ 605 606 .set_optval = { 1 << 3 }, 607 .set_optlen = 1, 608 .get_optval = { 1 << 3 }, 609 .get_optlen = 1, 610 }, 611 { 612 .descr = "setsockopt: read ctx->optlen", 613 .insns = { 614 /* r6 = ctx->optlen */ 615 BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1, 616 offsetof(struct bpf_sockopt, optlen)), 617 618 /* if (ctx->optlen == 64) { */ 619 BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 64, 4), 620 /* ctx->optlen = -1 */ 621 BPF_MOV64_IMM(BPF_REG_0, -1), 622 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 623 offsetof(struct bpf_sockopt, optlen)), 624 /* return 1 */ 625 BPF_MOV64_IMM(BPF_REG_0, 1), 626 BPF_JMP_A(1), 627 /* } else { */ 628 /* return 0 */ 629 BPF_MOV64_IMM(BPF_REG_0, 0), 630 /* } */ 631 BPF_EXIT_INSN(), 632 }, 633 .attach_type = BPF_CGROUP_SETSOCKOPT, 634 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 635 636 .set_optlen = 64, 637 .io_uring_support = true, 638 }, 639 { 640 .descr = "setsockopt: ctx->optlen == -1 is ok", 641 .insns = { 642 /* ctx->optlen = -1 */ 643 BPF_MOV64_IMM(BPF_REG_0, -1), 644 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 645 offsetof(struct bpf_sockopt, optlen)), 646 /* return 1 */ 647 BPF_MOV64_IMM(BPF_REG_0, 1), 648 BPF_EXIT_INSN(), 649 }, 650 .attach_type = BPF_CGROUP_SETSOCKOPT, 651 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 652 653 .set_optlen = 64, 654 .io_uring_support = true, 655 }, 656 { 657 .descr = "setsockopt: deny ctx->optlen < 0 (except -1)", 658 .insns = { 659 /* ctx->optlen = -2 */ 660 BPF_MOV64_IMM(BPF_REG_0, -2), 661 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 662 offsetof(struct bpf_sockopt, optlen)), 663 /* return 1 */ 664 BPF_MOV64_IMM(BPF_REG_0, 1), 665 BPF_EXIT_INSN(), 666 }, 667 .attach_type = BPF_CGROUP_SETSOCKOPT, 668 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 669 670 .set_optlen = 4, 671 672 .error = EFAULT_SETSOCKOPT, 673 .io_uring_support = true, 674 }, 675 { 676 .descr = "setsockopt: deny ctx->optlen > input optlen", 677 .insns = { 678 /* ctx->optlen = 65 */ 679 BPF_MOV64_IMM(BPF_REG_0, 65), 680 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 681 offsetof(struct bpf_sockopt, optlen)), 682 BPF_MOV64_IMM(BPF_REG_0, 1), 683 BPF_EXIT_INSN(), 684 }, 685 .attach_type = BPF_CGROUP_SETSOCKOPT, 686 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 687 688 .set_optlen = 64, 689 690 .error = EFAULT_SETSOCKOPT, 691 .io_uring_support = true, 692 }, 693 { 694 .descr = "setsockopt: ignore >PAGE_SIZE optlen", 695 .insns = { 696 /* write 0xFF to the first optval byte */ 697 698 /* r6 = ctx->optval */ 699 BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 700 offsetof(struct bpf_sockopt, optval)), 701 /* r2 = ctx->optval */ 702 BPF_MOV64_REG(BPF_REG_2, BPF_REG_6), 703 /* r6 = ctx->optval + 1 */ 704 BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 1), 705 706 /* r7 = ctx->optval_end */ 707 BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_1, 708 offsetof(struct bpf_sockopt, optval_end)), 709 710 /* if (ctx->optval + 1 <= ctx->optval_end) { */ 711 BPF_JMP_REG(BPF_JGT, BPF_REG_6, BPF_REG_7, 1), 712 /* ctx->optval[0] = 0xF0 */ 713 BPF_ST_MEM(BPF_B, BPF_REG_2, 0, 0xF0), 714 /* } */ 715 716 BPF_MOV64_IMM(BPF_REG_0, 1), 717 BPF_EXIT_INSN(), 718 }, 719 .attach_type = BPF_CGROUP_SETSOCKOPT, 720 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 721 722 .set_level = SOL_IP, 723 .set_optname = IP_TOS, 724 .set_optval = {}, 725 .set_optlen = PAGE_SIZE + 1, 726 727 .get_level = SOL_IP, 728 .get_optname = IP_TOS, 729 .get_optval = {}, /* the changes are ignored */ 730 .get_optlen = 4, 731 }, 732 { 733 .descr = "setsockopt: allow changing ctx->optlen within bounds", 734 .insns = { 735 /* r6 = ctx->optval */ 736 BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 737 offsetof(struct bpf_sockopt, optval)), 738 /* r2 = ctx->optval */ 739 BPF_MOV64_REG(BPF_REG_2, BPF_REG_6), 740 /* r6 = ctx->optval + 1 */ 741 BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 1), 742 743 /* r7 = ctx->optval_end */ 744 BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_1, 745 offsetof(struct bpf_sockopt, optval_end)), 746 747 /* if (ctx->optval + 1 <= ctx->optval_end) { */ 748 BPF_JMP_REG(BPF_JGT, BPF_REG_6, BPF_REG_7, 1), 749 /* ctx->optval[0] = 1 << 3 */ 750 BPF_ST_MEM(BPF_B, BPF_REG_2, 0, 1 << 3), 751 /* } */ 752 753 /* ctx->optlen = 1 */ 754 BPF_MOV64_IMM(BPF_REG_0, 1), 755 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 756 offsetof(struct bpf_sockopt, optlen)), 757 758 /* return 1*/ 759 BPF_MOV64_IMM(BPF_REG_0, 1), 760 BPF_EXIT_INSN(), 761 }, 762 .attach_type = BPF_CGROUP_SETSOCKOPT, 763 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 764 765 .get_level = SOL_IP, 766 .set_level = SOL_IP, 767 768 .get_optname = IP_TOS, 769 .set_optname = IP_TOS, 770 771 .set_optval = { 1, 1, 1, 1 }, 772 .set_optlen = 4, 773 .get_optval = { 1 << 3 }, 774 .get_optlen = 1, 775 }, 776 { 777 .descr = "setsockopt: deny write ctx->retval", 778 .insns = { 779 /* ctx->retval = 0 */ 780 BPF_MOV64_IMM(BPF_REG_0, 0), 781 BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 782 offsetof(struct bpf_sockopt, retval)), 783 784 /* return 1 */ 785 BPF_MOV64_IMM(BPF_REG_0, 1), 786 BPF_EXIT_INSN(), 787 }, 788 .attach_type = BPF_CGROUP_SETSOCKOPT, 789 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 790 791 .error = DENY_LOAD, 792 }, 793 { 794 .descr = "setsockopt: deny read ctx->retval", 795 .insns = { 796 /* r6 = ctx->retval */ 797 BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1, 798 offsetof(struct bpf_sockopt, retval)), 799 800 /* return 1 */ 801 BPF_MOV64_IMM(BPF_REG_0, 1), 802 BPF_EXIT_INSN(), 803 }, 804 .attach_type = BPF_CGROUP_SETSOCKOPT, 805 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 806 807 .error = DENY_LOAD, 808 }, 809 { 810 .descr = "setsockopt: deny writing to ctx->optval", 811 .insns = { 812 /* ctx->optval = 1 */ 813 BPF_MOV64_IMM(BPF_REG_0, 1), 814 BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 815 offsetof(struct bpf_sockopt, optval)), 816 BPF_EXIT_INSN(), 817 }, 818 .attach_type = BPF_CGROUP_SETSOCKOPT, 819 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 820 821 .error = DENY_LOAD, 822 }, 823 { 824 .descr = "setsockopt: deny writing to ctx->optval_end", 825 .insns = { 826 /* ctx->optval_end = 1 */ 827 BPF_MOV64_IMM(BPF_REG_0, 1), 828 BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 829 offsetof(struct bpf_sockopt, optval_end)), 830 BPF_EXIT_INSN(), 831 }, 832 .attach_type = BPF_CGROUP_SETSOCKOPT, 833 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 834 835 .error = DENY_LOAD, 836 }, 837 { 838 .descr = "setsockopt: allow IP_TOS <= 128", 839 .insns = { 840 /* r6 = ctx->optval */ 841 BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 842 offsetof(struct bpf_sockopt, optval)), 843 /* r7 = ctx->optval + 1 */ 844 BPF_MOV64_REG(BPF_REG_7, BPF_REG_6), 845 BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, 1), 846 847 /* r8 = ctx->optval_end */ 848 BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_1, 849 offsetof(struct bpf_sockopt, optval_end)), 850 851 /* if (ctx->optval + 1 <= ctx->optval_end) { */ 852 BPF_JMP_REG(BPF_JGT, BPF_REG_7, BPF_REG_8, 4), 853 854 /* r9 = ctx->optval[0] */ 855 BPF_LDX_MEM(BPF_B, BPF_REG_9, BPF_REG_6, 0), 856 857 /* if (ctx->optval[0] < 128) */ 858 BPF_JMP_IMM(BPF_JGT, BPF_REG_9, 128, 2), 859 BPF_MOV64_IMM(BPF_REG_0, 1), 860 BPF_JMP_A(1), 861 /* } */ 862 863 /* } else { */ 864 BPF_MOV64_IMM(BPF_REG_0, 0), 865 /* } */ 866 867 BPF_EXIT_INSN(), 868 }, 869 .attach_type = BPF_CGROUP_SETSOCKOPT, 870 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 871 872 .get_level = SOL_IP, 873 .set_level = SOL_IP, 874 875 .get_optname = IP_TOS, 876 .set_optname = IP_TOS, 877 878 .set_optval = { 0x80 }, 879 .set_optlen = 1, 880 .get_optval = { 0x80 }, 881 .get_optlen = 1, 882 }, 883 { 884 .descr = "setsockopt: deny IP_TOS > 128", 885 .insns = { 886 /* r6 = ctx->optval */ 887 BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 888 offsetof(struct bpf_sockopt, optval)), 889 /* r7 = ctx->optval + 1 */ 890 BPF_MOV64_REG(BPF_REG_7, BPF_REG_6), 891 BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, 1), 892 893 /* r8 = ctx->optval_end */ 894 BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_1, 895 offsetof(struct bpf_sockopt, optval_end)), 896 897 /* if (ctx->optval + 1 <= ctx->optval_end) { */ 898 BPF_JMP_REG(BPF_JGT, BPF_REG_7, BPF_REG_8, 4), 899 900 /* r9 = ctx->optval[0] */ 901 BPF_LDX_MEM(BPF_B, BPF_REG_9, BPF_REG_6, 0), 902 903 /* if (ctx->optval[0] < 128) */ 904 BPF_JMP_IMM(BPF_JGT, BPF_REG_9, 128, 2), 905 BPF_MOV64_IMM(BPF_REG_0, 1), 906 BPF_JMP_A(1), 907 /* } */ 908 909 /* } else { */ 910 BPF_MOV64_IMM(BPF_REG_0, 0), 911 /* } */ 912 913 BPF_EXIT_INSN(), 914 }, 915 .attach_type = BPF_CGROUP_SETSOCKOPT, 916 .expected_attach_type = BPF_CGROUP_SETSOCKOPT, 917 918 .get_level = SOL_IP, 919 .set_level = SOL_IP, 920 921 .get_optname = IP_TOS, 922 .set_optname = IP_TOS, 923 924 .set_optval = { 0x81 }, 925 .set_optlen = 1, 926 .get_optval = { 0x00 }, 927 .get_optlen = 1, 928 929 .error = EPERM_SETSOCKOPT, 930 }, 931 }; 932 933 static int load_prog(const struct bpf_insn *insns, 934 enum bpf_attach_type expected_attach_type) 935 { 936 LIBBPF_OPTS(bpf_prog_load_opts, opts, 937 .expected_attach_type = expected_attach_type, 938 .log_level = 2, 939 .log_buf = bpf_log_buf, 940 .log_size = sizeof(bpf_log_buf), 941 ); 942 int fd, insns_cnt = 0; 943 944 for (; 945 insns[insns_cnt].code != (BPF_JMP | BPF_EXIT); 946 insns_cnt++) { 947 } 948 insns_cnt++; 949 950 fd = bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCKOPT, NULL, "GPL", insns, insns_cnt, &opts); 951 if (verbose && fd < 0) 952 fprintf(stderr, "%s\n", bpf_log_buf); 953 954 return fd; 955 } 956 957 /* Core function that handles io_uring ring initialization, 958 * sending SQE with sockopt command and waiting for the CQE. 959 */ 960 static int uring_sockopt(int op, int fd, int level, int optname, 961 const void *optval, socklen_t optlen) 962 { 963 struct io_uring_cqe *cqe; 964 struct io_uring_sqe *sqe; 965 struct io_uring ring; 966 int err; 967 968 err = io_uring_queue_init(1, &ring, 0); 969 if (!ASSERT_OK(err, "io_uring initialization")) 970 return err; 971 972 sqe = io_uring_get_sqe(&ring); 973 if (!ASSERT_NEQ(sqe, NULL, "Get an SQE")) { 974 err = -1; 975 goto fail; 976 } 977 978 io_uring_prep_cmd(sqe, op, fd, level, optname, optval, optlen); 979 980 err = io_uring_submit(&ring); 981 if (!ASSERT_EQ(err, 1, "Submit SQE")) 982 goto fail; 983 984 err = io_uring_wait_cqe(&ring, &cqe); 985 if (!ASSERT_OK(err, "Wait for CQE")) 986 goto fail; 987 988 err = cqe->res; 989 990 fail: 991 io_uring_queue_exit(&ring); 992 993 return err; 994 } 995 996 static int uring_setsockopt(int fd, int level, int optname, const void *optval, 997 socklen_t optlen) 998 { 999 return uring_sockopt(SOCKET_URING_OP_SETSOCKOPT, fd, level, optname, 1000 optval, optlen); 1001 } 1002 1003 static int uring_getsockopt(int fd, int level, int optname, void *optval, 1004 socklen_t *optlen) 1005 { 1006 int ret = uring_sockopt(SOCKET_URING_OP_GETSOCKOPT, fd, level, optname, 1007 optval, *optlen); 1008 if (ret < 0) 1009 return ret; 1010 1011 /* Populate optlen back to be compatible with systemcall interface, 1012 * and simplify the test. 1013 */ 1014 *optlen = ret; 1015 1016 return 0; 1017 } 1018 1019 /* Execute the setsocktopt operation */ 1020 static int call_setsockopt(bool use_io_uring, int fd, int level, int optname, 1021 const void *optval, socklen_t optlen) 1022 { 1023 if (use_io_uring) 1024 return uring_setsockopt(fd, level, optname, optval, optlen); 1025 1026 return setsockopt(fd, level, optname, optval, optlen); 1027 } 1028 1029 /* Execute the getsocktopt operation */ 1030 static int call_getsockopt(bool use_io_uring, int fd, int level, int optname, 1031 void *optval, socklen_t *optlen) 1032 { 1033 if (use_io_uring) 1034 return uring_getsockopt(fd, level, optname, optval, optlen); 1035 1036 return getsockopt(fd, level, optname, optval, optlen); 1037 } 1038 1039 static int run_test(int cgroup_fd, struct sockopt_test *test, bool use_io_uring) 1040 { 1041 int sock_fd, err, prog_fd; 1042 void *optval = NULL; 1043 int ret = 0; 1044 1045 prog_fd = load_prog(test->insns, test->expected_attach_type); 1046 if (prog_fd < 0) { 1047 if (test->error == DENY_LOAD) 1048 return 0; 1049 1050 log_err("Failed to load BPF program"); 1051 return -1; 1052 } 1053 1054 err = bpf_prog_attach(prog_fd, cgroup_fd, test->attach_type, 0); 1055 if (err < 0) { 1056 if (test->error == DENY_ATTACH) 1057 goto close_prog_fd; 1058 1059 log_err("Failed to attach BPF program"); 1060 ret = -1; 1061 goto close_prog_fd; 1062 } 1063 1064 sock_fd = socket(AF_INET, SOCK_STREAM, 0); 1065 if (sock_fd < 0) { 1066 log_err("Failed to create AF_INET socket"); 1067 ret = -1; 1068 goto detach_prog; 1069 } 1070 1071 if (test->set_optlen) { 1072 if (test->set_optlen >= PAGE_SIZE) { 1073 int num_pages = test->set_optlen / PAGE_SIZE; 1074 int remainder = test->set_optlen % PAGE_SIZE; 1075 1076 test->set_optlen = num_pages * sysconf(_SC_PAGESIZE) + remainder; 1077 } 1078 1079 err = call_setsockopt(use_io_uring, sock_fd, test->set_level, 1080 test->set_optname, test->set_optval, 1081 test->set_optlen); 1082 if (err) { 1083 if (errno == EPERM && test->error == EPERM_SETSOCKOPT) 1084 goto close_sock_fd; 1085 if (errno == EFAULT && test->error == EFAULT_SETSOCKOPT) 1086 goto free_optval; 1087 1088 log_err("Failed to call setsockopt"); 1089 ret = -1; 1090 goto close_sock_fd; 1091 } 1092 } 1093 1094 if (test->get_optlen) { 1095 if (test->get_optlen >= PAGE_SIZE) { 1096 int num_pages = test->get_optlen / PAGE_SIZE; 1097 int remainder = test->get_optlen % PAGE_SIZE; 1098 1099 test->get_optlen = num_pages * sysconf(_SC_PAGESIZE) + remainder; 1100 } 1101 1102 optval = malloc(test->get_optlen); 1103 memset(optval, 0, test->get_optlen); 1104 socklen_t optlen = test->get_optlen; 1105 socklen_t expected_get_optlen = test->get_optlen_ret ?: 1106 test->get_optlen; 1107 1108 err = call_getsockopt(use_io_uring, sock_fd, test->get_level, 1109 test->get_optname, optval, &optlen); 1110 if (err) { 1111 if (errno == EOPNOTSUPP && test->error == EOPNOTSUPP_GETSOCKOPT) 1112 goto free_optval; 1113 if (errno == EPERM && test->error == EPERM_GETSOCKOPT) 1114 goto free_optval; 1115 if (errno == EFAULT && test->error == EFAULT_GETSOCKOPT) 1116 goto free_optval; 1117 1118 log_err("Failed to call getsockopt"); 1119 ret = -1; 1120 goto free_optval; 1121 } 1122 1123 if (optlen != expected_get_optlen) { 1124 errno = 0; 1125 log_err("getsockopt returned unexpected optlen"); 1126 ret = -1; 1127 goto free_optval; 1128 } 1129 1130 if (memcmp(optval, test->get_optval, optlen) != 0) { 1131 errno = 0; 1132 log_err("getsockopt returned unexpected optval"); 1133 ret = -1; 1134 goto free_optval; 1135 } 1136 } 1137 1138 ret = test->error != OK; 1139 1140 free_optval: 1141 free(optval); 1142 close_sock_fd: 1143 close(sock_fd); 1144 detach_prog: 1145 bpf_prog_detach2(prog_fd, cgroup_fd, test->attach_type); 1146 close_prog_fd: 1147 close(prog_fd); 1148 return ret; 1149 } 1150 1151 void test_sockopt(void) 1152 { 1153 int cgroup_fd, i; 1154 1155 cgroup_fd = test__join_cgroup("/sockopt"); 1156 if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup")) 1157 return; 1158 1159 for (i = 0; i < ARRAY_SIZE(tests); i++) { 1160 if (!test__start_subtest(tests[i].descr)) 1161 continue; 1162 1163 ASSERT_OK(run_test(cgroup_fd, &tests[i], false), 1164 tests[i].descr); 1165 if (tests[i].io_uring_support) 1166 ASSERT_OK(run_test(cgroup_fd, &tests[i], true), 1167 tests[i].descr); 1168 } 1169 1170 close(cgroup_fd); 1171 } 1172