1/* $OpenBSD: bcode.c,v 1.40 2009/10/27 23:59:37 deraadt Exp $ */ 2 3/* 4 * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19#include <sys/cdefs.h> 20__FBSDID("$FreeBSD$"); 21 22#include <err.h> 23#include <limits.h> 24#include <openssl/ssl.h> 25#include <signal.h> 26#include <stdio.h> 27#include <stdlib.h> 28#include <string.h> 29 30#include "extern.h" 31 32BIGNUM zero; 33 34#define __inline 35 36#define MAX_ARRAY_INDEX 2048 37#define READSTACK_SIZE 8 38 39#define NO_ELSE -2 /* -1 is EOF */ 40#define REG_ARRAY_SIZE_SMALL (UCHAR_MAX + 1) 41#define REG_ARRAY_SIZE_BIG (UCHAR_MAX + 1 + USHRT_MAX + 1) 42 43struct bmachine { 44 struct source *readstack; 45 struct stack *reg; 46 struct stack stack; 47 u_int scale; 48 u_int obase; 49 u_int ibase; 50 size_t readsp; 51 size_t reg_array_size; 52 size_t readstack_sz; 53 bool extended_regs; 54}; 55 56static struct bmachine bmachine; 57 58static __inline int readch(void); 59static __inline void unreadch(void); 60static __inline char *readline(void); 61static __inline void src_free(void); 62 63static __inline u_int max(u_int, u_int); 64static u_long get_ulong(struct number *); 65 66static __inline void push_number(struct number *); 67static __inline void push_string(char *); 68static __inline void push(struct value *); 69static __inline struct value *tos(void); 70static __inline struct number *pop_number(void); 71static __inline char *pop_string(void); 72static __inline void clear_stack(void); 73static __inline void print_tos(void); 74static void pop_print(void); 75static void pop_printn(void); 76static __inline void print_stack(void); 77static __inline void dup(void); 78static void swap(void); 79static void drop(void); 80 81static void get_scale(void); 82static void set_scale(void); 83static void get_obase(void); 84static void set_obase(void); 85static void get_ibase(void); 86static void set_ibase(void); 87static void stackdepth(void); 88static void push_scale(void); 89static u_int count_digits(const struct number *); 90static void num_digits(void); 91static void to_ascii(void); 92static void push_line(void); 93static void comment(void); 94static void bexec(char *); 95static void badd(void); 96static void bsub(void); 97static void bmul(void); 98static void bdiv(void); 99static void bmod(void); 100static void bdivmod(void); 101static void bexp(void); 102static bool bsqrt_stop(const BIGNUM *, const BIGNUM *, u_int *); 103static void bsqrt(void); 104static void not(void); 105static void equal_numbers(void); 106static void less_numbers(void); 107static void lesseq_numbers(void); 108static void equal(void); 109static void not_equal(void); 110static void less(void); 111static void not_less(void); 112static void greater(void); 113static void not_greater(void); 114static void not_compare(void); 115static bool compare_numbers(enum bcode_compare, struct number *, 116 struct number *); 117static void compare(enum bcode_compare); 118static int readreg(void); 119static void load(void); 120static void store(void); 121static void load_stack(void); 122static void store_stack(void); 123static void load_array(void); 124static void store_array(void); 125static void nop(void); 126static void quit(void); 127static void quitN(void); 128static void skipN(void); 129static void skip_until_mark(void); 130static void parse_number(void); 131static void unknown(void); 132static void eval_string(char *); 133static void eval_line(void); 134static void eval_tos(void); 135 136 137typedef void (*opcode_function)(void); 138 139struct jump_entry { 140 u_char ch; 141 opcode_function f; 142}; 143 144static opcode_function jump_table[UCHAR_MAX]; 145 146static const struct jump_entry jump_table_data[] = { 147 { ' ', nop }, 148 { '!', not_compare }, 149 { '#', comment }, 150 { '%', bmod }, 151 { '(', less_numbers }, 152 { '*', bmul }, 153 { '+', badd }, 154 { '-', bsub }, 155 { '.', parse_number }, 156 { '/', bdiv }, 157 { '0', parse_number }, 158 { '1', parse_number }, 159 { '2', parse_number }, 160 { '3', parse_number }, 161 { '4', parse_number }, 162 { '5', parse_number }, 163 { '6', parse_number }, 164 { '7', parse_number }, 165 { '8', parse_number }, 166 { '9', parse_number }, 167 { ':', store_array }, 168 { ';', load_array }, 169 { '<', less }, 170 { '=', equal }, 171 { '>', greater }, 172 { '?', eval_line }, 173 { 'A', parse_number }, 174 { 'B', parse_number }, 175 { 'C', parse_number }, 176 { 'D', parse_number }, 177 { 'E', parse_number }, 178 { 'F', parse_number }, 179 { 'G', equal_numbers }, 180 { 'I', get_ibase }, 181 { 'J', skipN }, 182 { 'K', get_scale }, 183 { 'L', load_stack }, 184 { 'M', nop }, 185 { 'N', not }, 186 { 'O', get_obase }, 187 { 'P', pop_print }, 188 { 'Q', quitN }, 189 { 'R', drop }, 190 { 'S', store_stack }, 191 { 'X', push_scale }, 192 { 'Z', num_digits }, 193 { '[', push_line }, 194 { '\f', nop }, 195 { '\n', nop }, 196 { '\r', nop }, 197 { '\t', nop }, 198 { '^', bexp }, 199 { '_', parse_number }, 200 { 'a', to_ascii }, 201 { 'c', clear_stack }, 202 { 'd', dup }, 203 { 'f', print_stack }, 204 { 'i', set_ibase }, 205 { 'k', set_scale }, 206 { 'l', load }, 207 { 'n', pop_printn }, 208 { 'o', set_obase }, 209 { 'p', print_tos }, 210 { 'q', quit }, 211 { 'r', swap }, 212 { 's', store }, 213 { 'v', bsqrt }, 214 { 'x', eval_tos }, 215 { 'z', stackdepth }, 216 { '{', lesseq_numbers }, 217 { '~', bdivmod } 218}; 219 220#define JUMP_TABLE_DATA_SIZE \ 221 (sizeof(jump_table_data)/sizeof(jump_table_data[0])) 222 223void 224init_bmachine(bool extended_registers) 225{ 226 unsigned int i; 227 228 bmachine.extended_regs = extended_registers; 229 bmachine.reg_array_size = bmachine.extended_regs ? 230 REG_ARRAY_SIZE_BIG : REG_ARRAY_SIZE_SMALL; 231 232 bmachine.reg = calloc(bmachine.reg_array_size, 233 sizeof(bmachine.reg[0])); 234 if (bmachine.reg == NULL) 235 err(1, NULL); 236 237 for (i = 0; i < UCHAR_MAX; i++) 238 jump_table[i] = unknown; 239 for (i = 0; i < JUMP_TABLE_DATA_SIZE; i++) 240 jump_table[jump_table_data[i].ch] = jump_table_data[i].f; 241 242 stack_init(&bmachine.stack); 243 244 for (i = 0; i < bmachine.reg_array_size; i++) 245 stack_init(&bmachine.reg[i]); 246 247 bmachine.readstack_sz = READSTACK_SIZE; 248 bmachine.readstack = calloc(sizeof(struct source), 249 bmachine.readstack_sz); 250 if (bmachine.readstack == NULL) 251 err(1, NULL); 252 bmachine.obase = bmachine.ibase = 10; 253 BN_init(&zero); 254 bn_check(BN_zero(&zero)); 255} 256 257/* Reset the things needed before processing a (new) file */ 258void 259reset_bmachine(struct source *src) 260{ 261 262 bmachine.readsp = 0; 263 bmachine.readstack[0] = *src; 264} 265 266static __inline int 267readch(void) 268{ 269 struct source *src = &bmachine.readstack[bmachine.readsp]; 270 271 return (src->vtable->readchar(src)); 272} 273 274static __inline void 275unreadch(void) 276{ 277 struct source *src = &bmachine.readstack[bmachine.readsp]; 278 279 src->vtable->unreadchar(src); 280} 281 282static __inline char * 283readline(void) 284{ 285 struct source *src = &bmachine.readstack[bmachine.readsp]; 286 287 return (src->vtable->readline(src)); 288} 289 290static __inline void 291src_free(void) 292{ 293 struct source *src = &bmachine.readstack[bmachine.readsp]; 294 295 src->vtable->free(src); 296} 297 298#ifdef DEBUGGING 299void 300pn(const char *str, const struct number *n) 301{ 302 char *p = BN_bn2dec(n->number); 303 304 if (p == NULL) 305 err(1, "BN_bn2dec failed"); 306 fputs(str, stderr); 307 fprintf(stderr, " %s (%u)\n" , p, n->scale); 308 OPENSSL_free(p); 309} 310 311void 312pbn(const char *str, const BIGNUM *n) 313{ 314 char *p = BN_bn2dec(n); 315 316 if (p == NULL) 317 err(1, "BN_bn2dec failed"); 318 fputs(str, stderr); 319 fprintf(stderr, " %s\n", p); 320 OPENSSL_free(p); 321} 322 323#endif 324 325static __inline u_int 326max(u_int a, u_int b) 327{ 328 329 return (a > b ? a : b); 330} 331 332static unsigned long factors[] = { 333 0, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 334 100000000, 1000000000 335}; 336 337void 338scale_number(BIGNUM *n, int s) 339{ 340 unsigned int abs_scale; 341 342 if (s == 0) 343 return; 344 345 abs_scale = s > 0 ? s : -s; 346 347 if (abs_scale < sizeof(factors)/sizeof(factors[0])) { 348 if (s > 0) 349 bn_check(BN_mul_word(n, factors[abs_scale])); 350 else 351 BN_div_word(n, factors[abs_scale]); 352 } else { 353 BIGNUM *a, *p; 354 BN_CTX *ctx; 355 356 a = BN_new(); 357 bn_checkp(a); 358 p = BN_new(); 359 bn_checkp(p); 360 ctx = BN_CTX_new(); 361 bn_checkp(ctx); 362 363 bn_check(BN_set_word(a, 10)); 364 bn_check(BN_set_word(p, abs_scale)); 365 bn_check(BN_exp(a, a, p, ctx)); 366 if (s > 0) 367 bn_check(BN_mul(n, n, a, ctx)); 368 else 369 bn_check(BN_div(n, NULL, n, a, ctx)); 370 BN_CTX_free(ctx); 371 BN_free(a); 372 BN_free(p); 373 } 374} 375 376void 377split_number(const struct number *n, BIGNUM *i, BIGNUM *f) 378{ 379 u_long rem; 380 381 bn_checkp(BN_copy(i, n->number)); 382 383 if (n->scale == 0 && f != NULL) 384 bn_check(BN_zero(f)); 385 else if (n->scale < sizeof(factors)/sizeof(factors[0])) { 386 rem = BN_div_word(i, factors[n->scale]); 387 if (f != NULL) 388 bn_check(BN_set_word(f, rem)); 389 } else { 390 BIGNUM *a, *p; 391 BN_CTX *ctx; 392 393 a = BN_new(); 394 bn_checkp(a); 395 p = BN_new(); 396 bn_checkp(p); 397 ctx = BN_CTX_new(); 398 bn_checkp(ctx); 399 400 bn_check(BN_set_word(a, 10)); 401 bn_check(BN_set_word(p, n->scale)); 402 bn_check(BN_exp(a, a, p, ctx)); 403 bn_check(BN_div(i, f, n->number, a, ctx)); 404 BN_CTX_free(ctx); 405 BN_free(a); 406 BN_free(p); 407 } 408} 409 410__inline void 411normalize(struct number *n, u_int s) 412{ 413 414 scale_number(n->number, s - n->scale); 415 n->scale = s; 416} 417 418static u_long 419get_ulong(struct number *n) 420{ 421 422 normalize(n, 0); 423 return (BN_get_word(n->number)); 424} 425 426void 427negate(struct number *n) 428{ 429 430 bn_check(BN_sub(n->number, &zero, n->number)); 431} 432 433static __inline void 434push_number(struct number *n) 435{ 436 437 stack_pushnumber(&bmachine.stack, n); 438} 439 440static __inline void 441push_string(char *string) 442{ 443 444 stack_pushstring(&bmachine.stack, string); 445} 446 447static __inline void 448push(struct value *v) 449{ 450 451 stack_push(&bmachine.stack, v); 452} 453 454static __inline struct value * 455tos(void) 456{ 457 458 return (stack_tos(&bmachine.stack)); 459} 460 461static __inline struct value * 462pop(void) 463{ 464 465 return (stack_pop(&bmachine.stack)); 466} 467 468static __inline struct number * 469pop_number(void) 470{ 471 472 return (stack_popnumber(&bmachine.stack)); 473} 474 475static __inline char * 476pop_string(void) 477{ 478 479 return (stack_popstring(&bmachine.stack)); 480} 481 482static __inline void 483clear_stack(void) 484{ 485 486 stack_clear(&bmachine.stack); 487} 488 489static __inline void 490print_stack(void) 491{ 492 493 stack_print(stdout, &bmachine.stack, "", bmachine.obase); 494} 495 496static __inline void 497print_tos(void) 498{ 499 struct value *value = tos(); 500 501 if (value != NULL) { 502 print_value(stdout, value, "", bmachine.obase); 503 putchar('\n'); 504 } 505 else 506 warnx("stack empty"); 507} 508 509static void 510pop_print(void) 511{ 512 struct value *value = pop(); 513 514 if (value != NULL) { 515 switch (value->type) { 516 case BCODE_NONE: 517 break; 518 case BCODE_NUMBER: 519 normalize(value->u.num, 0); 520 print_ascii(stdout, value->u.num); 521 fflush(stdout); 522 break; 523 case BCODE_STRING: 524 fputs(value->u.string, stdout); 525 fflush(stdout); 526 break; 527 } 528 stack_free_value(value); 529 } 530} 531 532static void 533pop_printn(void) 534{ 535 struct value *value = pop(); 536 537 if (value != NULL) { 538 print_value(stdout, value, "", bmachine.obase); 539 fflush(stdout); 540 stack_free_value(value); 541 } 542} 543 544static __inline void 545dup(void) 546{ 547 548 stack_dup(&bmachine.stack); 549} 550 551static void 552swap(void) 553{ 554 555 stack_swap(&bmachine.stack); 556} 557 558static void 559drop(void) 560{ 561 struct value *v = pop(); 562 if (v != NULL) 563 stack_free_value(v); 564} 565 566static void 567get_scale(void) 568{ 569 struct number *n; 570 571 n = new_number(); 572 bn_check(BN_set_word(n->number, bmachine.scale)); 573 push_number(n); 574} 575 576static void 577set_scale(void) 578{ 579 struct number *n; 580 u_long scale; 581 582 n = pop_number(); 583 if (n != NULL) { 584 if (BN_cmp(n->number, &zero) < 0) 585 warnx("scale must be a nonnegative number"); 586 else { 587 scale = get_ulong(n); 588 if (scale != BN_MASK2 && scale <= UINT_MAX) 589 bmachine.scale = (u_int)scale; 590 else 591 warnx("scale too large"); 592 } 593 free_number(n); 594 } 595} 596 597static void 598get_obase(void) 599{ 600 struct number *n; 601 602 n = new_number(); 603 bn_check(BN_set_word(n->number, bmachine.obase)); 604 push_number(n); 605} 606 607static void 608set_obase(void) 609{ 610 struct number *n; 611 u_long base; 612 613 n = pop_number(); 614 if (n != NULL) { 615 base = get_ulong(n); 616 if (base != BN_MASK2 && base > 1 && base <= UINT_MAX) 617 bmachine.obase = (u_int)base; 618 else 619 warnx("output base must be a number greater than 1"); 620 free_number(n); 621 } 622} 623 624static void 625get_ibase(void) 626{ 627 struct number *n; 628 629 n = new_number(); 630 bn_check(BN_set_word(n->number, bmachine.ibase)); 631 push_number(n); 632} 633 634static void 635set_ibase(void) 636{ 637 struct number *n; 638 u_long base; 639 640 n = pop_number(); 641 if (n != NULL) { 642 base = get_ulong(n); 643 if (base != BN_MASK2 && 2 <= base && base <= 16) 644 bmachine.ibase = (u_int)base; 645 else 646 warnx("input base must be a number between 2 and 16 " 647 "(inclusive)"); 648 free_number(n); 649 } 650} 651 652static void 653stackdepth(void) 654{ 655 struct number *n; 656 size_t i; 657 658 i = stack_size(&bmachine.stack); 659 n = new_number(); 660 bn_check(BN_set_word(n->number, i)); 661 push_number(n); 662} 663 664static void 665push_scale(void) 666{ 667 struct number *n; 668 struct value *value; 669 u_int scale = 0; 670 671 value = pop(); 672 if (value != NULL) { 673 switch (value->type) { 674 case BCODE_NONE: 675 return; 676 case BCODE_NUMBER: 677 scale = value->u.num->scale; 678 break; 679 case BCODE_STRING: 680 break; 681 } 682 stack_free_value(value); 683 n = new_number(); 684 bn_check(BN_set_word(n->number, scale)); 685 push_number(n); 686 } 687} 688 689static u_int 690count_digits(const struct number *n) 691{ 692 struct number *int_part, *fract_part; 693 u_int i; 694 695 if (BN_is_zero(n->number)) 696 return (n->scale ? n->scale : 1); 697 698 int_part = new_number(); 699 fract_part = new_number(); 700 fract_part->scale = n->scale; 701 split_number(n, int_part->number, fract_part->number); 702 703 i = 0; 704 while (!BN_is_zero(int_part->number)) { 705 BN_div_word(int_part->number, 10); 706 i++; 707 } 708 free_number(int_part); 709 free_number(fract_part); 710 return (i + n->scale); 711} 712 713static void 714num_digits(void) 715{ 716 struct number *n = NULL; 717 struct value *value; 718 size_t digits; 719 720 value = pop(); 721 if (value != NULL) { 722 switch (value->type) { 723 case BCODE_NONE: 724 return; 725 case BCODE_NUMBER: 726 digits = count_digits(value->u.num); 727 n = new_number(); 728 bn_check(BN_set_word(n->number, digits)); 729 break; 730 case BCODE_STRING: 731 digits = strlen(value->u.string); 732 n = new_number(); 733 bn_check(BN_set_word(n->number, digits)); 734 break; 735 } 736 stack_free_value(value); 737 push_number(n); 738 } 739} 740 741static void 742to_ascii(void) 743{ 744 struct number *n; 745 struct value *value; 746 char str[2]; 747 748 value = pop(); 749 if (value != NULL) { 750 str[1] = '\0'; 751 switch (value->type) { 752 case BCODE_NONE: 753 return; 754 case BCODE_NUMBER: 755 n = value->u.num; 756 normalize(n, 0); 757 if (BN_num_bits(n->number) > 8) 758 bn_check(BN_mask_bits(n->number, 8)); 759 str[0] = (char)BN_get_word(n->number); 760 break; 761 case BCODE_STRING: 762 str[0] = value->u.string[0]; 763 break; 764 } 765 stack_free_value(value); 766 push_string(bstrdup(str)); 767 } 768} 769 770static int 771readreg(void) 772{ 773 int ch1, ch2, idx; 774 775 idx = readch(); 776 if (idx == 0xff && bmachine.extended_regs) { 777 ch1 = readch(); 778 ch2 = readch(); 779 if (ch1 == EOF || ch2 == EOF) { 780 warnx("unexpected eof"); 781 idx = -1; 782 } else 783 idx = (ch1 << 8) + ch2 + UCHAR_MAX + 1; 784 } 785 if (idx < 0 || (unsigned)idx >= bmachine.reg_array_size) { 786 warnx("internal error: reg num = %d", idx); 787 idx = -1; 788 } 789 return (idx); 790} 791 792static void 793load(void) 794{ 795 struct number *n; 796 struct value *v; 797 struct value copy; 798 int idx; 799 800 idx = readreg(); 801 if (idx >= 0) { 802 v = stack_tos(&bmachine.reg[idx]); 803 if (v == NULL) { 804 n = new_number(); 805 bn_check(BN_zero(n->number)); 806 push_number(n); 807 } else 808 push(stack_dup_value(v, ©)); 809 } 810} 811 812static void 813store(void) 814{ 815 struct value *val; 816 int idx; 817 818 idx = readreg(); 819 if (idx >= 0) { 820 val = pop(); 821 if (val == NULL) { 822 return; 823 } 824 stack_set_tos(&bmachine.reg[idx], val); 825 } 826} 827 828static void 829load_stack(void) 830{ 831 struct stack *stack; 832 struct value *value; 833 int idx; 834 835 idx = readreg(); 836 if (idx >= 0) { 837 stack = &bmachine.reg[idx]; 838 value = NULL; 839 if (stack_size(stack) > 0) { 840 value = stack_pop(stack); 841 } 842 if (value != NULL) 843 push(value); 844 else 845 warnx("stack register '%c' (0%o) is empty", 846 idx, idx); 847 } 848} 849 850static void 851store_stack(void) 852{ 853 struct value *value; 854 int idx; 855 856 idx = readreg(); 857 if (idx >= 0) { 858 value = pop(); 859 if (value == NULL) 860 return; 861 stack_push(&bmachine.reg[idx], value); 862 } 863} 864 865static void 866load_array(void) 867{ 868 struct number *inumber, *n; 869 struct stack *stack; 870 struct value *v; 871 struct value copy; 872 u_long idx; 873 int reg; 874 875 reg = readreg(); 876 if (reg >= 0) { 877 inumber = pop_number(); 878 if (inumber == NULL) 879 return; 880 idx = get_ulong(inumber); 881 if (BN_cmp(inumber->number, &zero) < 0) 882 warnx("negative idx"); 883 else if (idx == BN_MASK2 || idx > MAX_ARRAY_INDEX) 884 warnx("idx too big"); 885 else { 886 stack = &bmachine.reg[reg]; 887 v = frame_retrieve(stack, idx); 888 if (v == NULL || v->type == BCODE_NONE) { 889 n = new_number(); 890 bn_check(BN_zero(n->number)); 891 push_number(n); 892 } 893 else 894 push(stack_dup_value(v, ©)); 895 } 896 free_number(inumber); 897 } 898} 899 900static void 901store_array(void) 902{ 903 struct number *inumber; 904 struct value *value; 905 struct stack *stack; 906 u_long idx; 907 int reg; 908 909 reg = readreg(); 910 if (reg >= 0) { 911 inumber = pop_number(); 912 if (inumber == NULL) 913 return; 914 value = pop(); 915 if (value == NULL) { 916 free_number(inumber); 917 return; 918 } 919 idx = get_ulong(inumber); 920 if (BN_cmp(inumber->number, &zero) < 0) { 921 warnx("negative idx"); 922 stack_free_value(value); 923 } else if (idx == BN_MASK2 || idx > MAX_ARRAY_INDEX) { 924 warnx("idx too big"); 925 stack_free_value(value); 926 } else { 927 stack = &bmachine.reg[reg]; 928 frame_assign(stack, idx, value); 929 } 930 free_number(inumber); 931 } 932} 933 934static void 935push_line(void) 936{ 937 938 push_string(read_string(&bmachine.readstack[bmachine.readsp])); 939} 940 941static void 942comment(void) 943{ 944 945 free(readline()); 946} 947 948static void 949bexec(char *line) 950{ 951 952 system(line); 953 free(line); 954} 955 956static void 957badd(void) 958{ 959 struct number *a, *b, *r; 960 961 a = pop_number(); 962 if (a == NULL) { 963 return; 964 } 965 b = pop_number(); 966 if (b == NULL) { 967 push_number(a); 968 return; 969 } 970 971 r = new_number(); 972 r->scale = max(a->scale, b->scale); 973 if (r->scale > a->scale) 974 normalize(a, r->scale); 975 else if (r->scale > b->scale) 976 normalize(b, r->scale); 977 bn_check(BN_add(r->number, a->number, b->number)); 978 push_number(r); 979 free_number(a); 980 free_number(b); 981} 982 983static void 984bsub(void) 985{ 986 struct number *a, *b, *r; 987 988 a = pop_number(); 989 if (a == NULL) { 990 return; 991 } 992 b = pop_number(); 993 if (b == NULL) { 994 push_number(a); 995 return; 996 } 997 998 r = new_number(); 999 1000 r->scale = max(a->scale, b->scale); 1001 if (r->scale > a->scale) 1002 normalize(a, r->scale); 1003 else if (r->scale > b->scale) 1004 normalize(b, r->scale); 1005 bn_check(BN_sub(r->number, b->number, a->number)); 1006 push_number(r); 1007 free_number(a); 1008 free_number(b); 1009} 1010 1011void 1012bmul_number(struct number *r, struct number *a, struct number *b) 1013{ 1014 BN_CTX *ctx; 1015 1016 /* Create copies of the scales, since r might be equal to a or b */ 1017 u_int ascale = a->scale; 1018 u_int bscale = b->scale; 1019 u_int rscale = ascale + bscale; 1020 1021 ctx = BN_CTX_new(); 1022 bn_checkp(ctx); 1023 bn_check(BN_mul(r->number, a->number, b->number, ctx)); 1024 BN_CTX_free(ctx); 1025 1026 if (rscale > bmachine.scale && rscale > ascale && rscale > bscale) { 1027 r->scale = rscale; 1028 normalize(r, max(bmachine.scale, max(ascale, bscale))); 1029 } else 1030 r->scale = rscale; 1031} 1032 1033static void 1034bmul(void) 1035{ 1036 struct number *a, *b, *r; 1037 1038 a = pop_number(); 1039 if (a == NULL) { 1040 return; 1041 } 1042 b = pop_number(); 1043 if (b == NULL) { 1044 push_number(a); 1045 return; 1046 } 1047 1048 r = new_number(); 1049 bmul_number(r, a, b); 1050 1051 push_number(r); 1052 free_number(a); 1053 free_number(b); 1054} 1055 1056static void 1057bdiv(void) 1058{ 1059 struct number *a, *b, *r; 1060 BN_CTX *ctx; 1061 u_int scale; 1062 1063 a = pop_number(); 1064 if (a == NULL) { 1065 return; 1066 } 1067 b = pop_number(); 1068 if (b == NULL) { 1069 push_number(a); 1070 return; 1071 } 1072 1073 r = new_number(); 1074 r->scale = bmachine.scale; 1075 scale = max(a->scale, b->scale); 1076 1077 if (BN_is_zero(a->number)) 1078 warnx("divide by zero"); 1079 else { 1080 normalize(a, scale); 1081 normalize(b, scale + r->scale); 1082 1083 ctx = BN_CTX_new(); 1084 bn_checkp(ctx); 1085 bn_check(BN_div(r->number, NULL, b->number, a->number, ctx)); 1086 BN_CTX_free(ctx); 1087 } 1088 push_number(r); 1089 free_number(a); 1090 free_number(b); 1091} 1092 1093static void 1094bmod(void) 1095{ 1096 struct number *a, *b, *r; 1097 BN_CTX *ctx; 1098 u_int scale; 1099 1100 a = pop_number(); 1101 if (a == NULL) { 1102 return; 1103 } 1104 b = pop_number(); 1105 if (b == NULL) { 1106 push_number(a); 1107 return; 1108 } 1109 1110 r = new_number(); 1111 scale = max(a->scale, b->scale); 1112 r->scale = max(b->scale, a->scale + bmachine.scale); 1113 1114 if (BN_is_zero(a->number)) 1115 warnx("remainder by zero"); 1116 else { 1117 normalize(a, scale); 1118 normalize(b, scale + bmachine.scale); 1119 1120 ctx = BN_CTX_new(); 1121 bn_checkp(ctx); 1122 bn_check(BN_mod(r->number, b->number, a->number, ctx)); 1123 BN_CTX_free(ctx); 1124 } 1125 push_number(r); 1126 free_number(a); 1127 free_number(b); 1128} 1129 1130static void 1131bdivmod(void) 1132{ 1133 struct number *a, *b, *rdiv, *rmod; 1134 BN_CTX *ctx; 1135 u_int scale; 1136 1137 a = pop_number(); 1138 if (a == NULL) { 1139 return; 1140 } 1141 b = pop_number(); 1142 if (b == NULL) { 1143 push_number(a); 1144 return; 1145 } 1146 1147 rdiv = new_number(); 1148 rmod = new_number(); 1149 rdiv->scale = bmachine.scale; 1150 rmod->scale = max(b->scale, a->scale + bmachine.scale); 1151 scale = max(a->scale, b->scale); 1152 1153 if (BN_is_zero(a->number)) 1154 warnx("divide by zero"); 1155 else { 1156 normalize(a, scale); 1157 normalize(b, scale + bmachine.scale); 1158 1159 ctx = BN_CTX_new(); 1160 bn_checkp(ctx); 1161 bn_check(BN_div(rdiv->number, rmod->number, 1162 b->number, a->number, ctx)); 1163 BN_CTX_free(ctx); 1164 } 1165 push_number(rdiv); 1166 push_number(rmod); 1167 free_number(a); 1168 free_number(b); 1169} 1170 1171static void 1172bexp(void) 1173{ 1174 struct number *a, *p, *r; 1175 u_int scale; 1176 bool neg; 1177 1178 p = pop_number(); 1179 if (p == NULL) { 1180 return; 1181 } 1182 a = pop_number(); 1183 if (a == NULL) { 1184 push_number(p); 1185 return; 1186 } 1187 1188 if (p->scale != 0) 1189 warnx("Runtime warning: non-zero scale in exponent"); 1190 normalize(p, 0); 1191 1192 neg = false; 1193 if (BN_cmp(p->number, &zero) < 0) { 1194 neg = true; 1195 negate(p); 1196 scale = bmachine.scale; 1197 } else { 1198 /* Posix bc says min(a.scale * b, max(a.scale, scale) */ 1199 u_long b; 1200 u_int m; 1201 1202 b = BN_get_word(p->number); 1203 m = max(a->scale, bmachine.scale); 1204 scale = a->scale * (u_int)b; 1205 if (scale > m || (a->scale > 0 && (b == BN_MASK2 || 1206 b > UINT_MAX))) 1207 scale = m; 1208 } 1209 1210 if (BN_is_zero(p->number)) { 1211 r = new_number(); 1212 bn_check(BN_one(r->number)); 1213 normalize(r, scale); 1214 } else { 1215 while (!BN_is_bit_set(p->number, 0)) { 1216 bmul_number(a, a, a); 1217 bn_check(BN_rshift1(p->number, p->number)); 1218 } 1219 1220 r = dup_number(a); 1221 normalize(r, scale); 1222 bn_check(BN_rshift1(p->number, p->number)); 1223 1224 while (!BN_is_zero(p->number)) { 1225 bmul_number(a, a, a); 1226 if (BN_is_bit_set(p->number, 0)) 1227 bmul_number(r, r, a); 1228 bn_check(BN_rshift1(p->number, p->number)); 1229 } 1230 1231 if (neg) { 1232 BN_CTX *ctx; 1233 BIGNUM *one; 1234 1235 one = BN_new(); 1236 bn_checkp(one); 1237 bn_check(BN_one(one)); 1238 ctx = BN_CTX_new(); 1239 bn_checkp(ctx); 1240 scale_number(one, r->scale + scale); 1241 normalize(r, scale); 1242 bn_check(BN_div(r->number, NULL, one, r->number, ctx)); 1243 BN_free(one); 1244 BN_CTX_free(ctx); 1245 } else 1246 normalize(r, scale); 1247 } 1248 push_number(r); 1249 free_number(a); 1250 free_number(p); 1251} 1252 1253static bool 1254bsqrt_stop(const BIGNUM *x, const BIGNUM *y, u_int *onecount) 1255{ 1256 BIGNUM *r; 1257 bool ret; 1258 1259 r = BN_new(); 1260 bn_checkp(r); 1261 bn_check(BN_sub(r, x, y)); 1262 if (BN_is_one(r)) 1263 (*onecount)++; 1264 ret = BN_is_zero(r); 1265 BN_free(r); 1266 return (ret || *onecount > 1); 1267} 1268 1269static void 1270bsqrt(void) 1271{ 1272 struct number *n, *r; 1273 BIGNUM *x, *y; 1274 BN_CTX *ctx; 1275 u_int onecount, scale; 1276 1277 onecount = 0; 1278 n = pop_number(); 1279 if (n == NULL) { 1280 return; 1281 } 1282 if (BN_is_zero(n->number)) { 1283 r = new_number(); 1284 push_number(r); 1285 } else if (BN_cmp(n->number, &zero) < 0) 1286 warnx("square root of negative number"); 1287 else { 1288 scale = max(bmachine.scale, n->scale); 1289 normalize(n, 2*scale); 1290 x = BN_dup(n->number); 1291 bn_checkp(x); 1292 bn_check(BN_rshift(x, x, BN_num_bits(x)/2)); 1293 y = BN_new(); 1294 bn_checkp(y); 1295 ctx = BN_CTX_new(); 1296 bn_checkp(ctx); 1297 for (;;) { 1298 bn_checkp(BN_copy(y, x)); 1299 bn_check(BN_div(x, NULL, n->number, x, ctx)); 1300 bn_check(BN_add(x, x, y)); 1301 bn_check(BN_rshift1(x, x)); 1302 if (bsqrt_stop(x, y, &onecount)) 1303 break; 1304 } 1305 r = bmalloc(sizeof(*r)); 1306 r->scale = scale; 1307 r->number = y; 1308 BN_free(x); 1309 BN_CTX_free(ctx); 1310 push_number(r); 1311 } 1312 1313 free_number(n); 1314} 1315 1316static void 1317not(void) 1318{ 1319 struct number *a; 1320 1321 a = pop_number(); 1322 if (a == NULL) { 1323 return; 1324 } 1325 a->scale = 0; 1326 bn_check(BN_set_word(a->number, BN_get_word(a->number) ? 0 : 1)); 1327 push_number(a); 1328} 1329 1330static void 1331equal(void) 1332{ 1333 1334 compare(BCODE_EQUAL); 1335} 1336 1337static void 1338equal_numbers(void) 1339{ 1340 struct number *a, *b, *r; 1341 1342 a = pop_number(); 1343 if (a == NULL) { 1344 return; 1345 } 1346 b = pop_number(); 1347 if (b == NULL) { 1348 push_number(a); 1349 return; 1350 } 1351 r = new_number(); 1352 bn_check(BN_set_word(r->number, 1353 compare_numbers(BCODE_EQUAL, a, b) ? 1 : 0)); 1354 push_number(r); 1355} 1356 1357static void 1358less_numbers(void) 1359{ 1360 struct number *a, *b, *r; 1361 1362 a = pop_number(); 1363 if (a == NULL) { 1364 return; 1365 } 1366 b = pop_number(); 1367 if (b == NULL) { 1368 push_number(a); 1369 return; 1370 } 1371 r = new_number(); 1372 bn_check(BN_set_word(r->number, 1373 compare_numbers(BCODE_LESS, a, b) ? 1 : 0)); 1374 push_number(r); 1375} 1376 1377static void 1378lesseq_numbers(void) 1379{ 1380 struct number *a, *b, *r; 1381 1382 a = pop_number(); 1383 if (a == NULL) { 1384 return; 1385 } 1386 b = pop_number(); 1387 if (b == NULL) { 1388 push_number(a); 1389 return; 1390 } 1391 r = new_number(); 1392 bn_check(BN_set_word(r->number, 1393 compare_numbers(BCODE_NOT_GREATER, a, b) ? 1 : 0)); 1394 push_number(r); 1395} 1396 1397static void 1398not_equal(void) 1399{ 1400 1401 compare(BCODE_NOT_EQUAL); 1402} 1403 1404static void 1405less(void) 1406{ 1407 1408 compare(BCODE_LESS); 1409} 1410 1411static void 1412not_compare(void) 1413{ 1414 1415 switch (readch()) { 1416 case '<': 1417 not_less(); 1418 break; 1419 case '>': 1420 not_greater(); 1421 break; 1422 case '=': 1423 not_equal(); 1424 break; 1425 default: 1426 unreadch(); 1427 bexec(readline()); 1428 break; 1429 } 1430} 1431 1432static void 1433not_less(void) 1434{ 1435 1436 compare(BCODE_NOT_LESS); 1437} 1438 1439static void 1440greater(void) 1441{ 1442 1443 compare(BCODE_GREATER); 1444} 1445 1446static void 1447not_greater(void) 1448{ 1449 1450 compare(BCODE_NOT_GREATER); 1451} 1452 1453static bool 1454compare_numbers(enum bcode_compare type, struct number *a, struct number *b) 1455{ 1456 u_int scale; 1457 int cmp; 1458 1459 scale = max(a->scale, b->scale); 1460 1461 if (scale > a->scale) 1462 normalize(a, scale); 1463 else if (scale > b->scale) 1464 normalize(b, scale); 1465 1466 cmp = BN_cmp(a->number, b->number); 1467 1468 free_number(a); 1469 free_number(b); 1470 1471 switch (type) { 1472 case BCODE_EQUAL: 1473 return (cmp == 0); 1474 case BCODE_NOT_EQUAL: 1475 return (cmp != 0); 1476 case BCODE_LESS: 1477 return (cmp < 0); 1478 case BCODE_NOT_LESS: 1479 return (cmp >= 0); 1480 case BCODE_GREATER: 1481 return (cmp > 0); 1482 case BCODE_NOT_GREATER: 1483 return (cmp <= 0); 1484 } 1485 return (false); 1486} 1487 1488static void 1489compare(enum bcode_compare type) 1490{ 1491 struct number *a, *b; 1492 struct value *v; 1493 int idx, elseidx; 1494 bool ok; 1495 1496 elseidx = NO_ELSE; 1497 idx = readreg(); 1498 if (readch() == 'e') 1499 elseidx = readreg(); 1500 else 1501 unreadch(); 1502 1503 a = pop_number(); 1504 if (a == NULL) 1505 return; 1506 b = pop_number(); 1507 if (b == NULL) { 1508 push_number(a); 1509 return; 1510 } 1511 1512 ok = compare_numbers(type, a, b); 1513 1514 if (!ok && elseidx != NO_ELSE) 1515 idx = elseidx; 1516 1517 if (idx >= 0 && (ok || (!ok && elseidx != NO_ELSE))) { 1518 v = stack_tos(&bmachine.reg[idx]); 1519 if (v == NULL) 1520 warnx("register '%c' (0%o) is empty", idx, idx); 1521 else { 1522 switch(v->type) { 1523 case BCODE_NONE: 1524 warnx("register '%c' (0%o) is empty", idx, idx); 1525 break; 1526 case BCODE_NUMBER: 1527 warn("eval called with non-string argument"); 1528 break; 1529 case BCODE_STRING: 1530 eval_string(bstrdup(v->u.string)); 1531 break; 1532 } 1533 } 1534 } 1535} 1536 1537 1538static void 1539nop(void) 1540{ 1541 1542} 1543 1544static void 1545quit(void) 1546{ 1547 1548 if (bmachine.readsp < 2) 1549 exit(0); 1550 src_free(); 1551 bmachine.readsp--; 1552 src_free(); 1553 bmachine.readsp--; 1554} 1555 1556static void 1557quitN(void) 1558{ 1559 struct number *n; 1560 u_long i; 1561 1562 n = pop_number(); 1563 if (n == NULL) 1564 return; 1565 i = get_ulong(n); 1566 free_number(n); 1567 if (i == BN_MASK2 || i == 0) 1568 warnx("Q command requires a number >= 1"); 1569 else if (bmachine.readsp < i) 1570 warnx("Q command argument exceeded string execution depth"); 1571 else { 1572 while (i-- > 0) { 1573 src_free(); 1574 bmachine.readsp--; 1575 } 1576 } 1577} 1578 1579static void 1580skipN(void) 1581{ 1582 struct number *n; 1583 u_long i; 1584 1585 n = pop_number(); 1586 if (n == NULL) 1587 return; 1588 i = get_ulong(n); 1589 if (i == BN_MASK2) 1590 warnx("J command requires a number >= 0"); 1591 else if (i > 0 && bmachine.readsp < i) 1592 warnx("J command argument exceeded string execution depth"); 1593 else { 1594 while (i-- > 0) { 1595 src_free(); 1596 bmachine.readsp--; 1597 } 1598 skip_until_mark(); 1599 } 1600} 1601 1602static void 1603skip_until_mark(void) 1604{ 1605 1606 for (;;) { 1607 switch (readch()) { 1608 case 'M': 1609 return; 1610 case EOF: 1611 errx(1, "mark not found"); 1612 return; 1613 case 'l': 1614 case 'L': 1615 case 's': 1616 case 'S': 1617 case ':': 1618 case ';': 1619 case '<': 1620 case '>': 1621 case '=': 1622 readreg(); 1623 if (readch() == 'e') 1624 readreg(); 1625 else 1626 unreadch(); 1627 break; 1628 case '[': 1629 free(read_string(&bmachine.readstack[bmachine.readsp])); 1630 break; 1631 case '!': 1632 switch (readch()) { 1633 case '<': 1634 case '>': 1635 case '=': 1636 readreg(); 1637 if (readch() == 'e') 1638 readreg(); 1639 else 1640 unreadch(); 1641 break; 1642 default: 1643 free(readline()); 1644 break; 1645 } 1646 break; 1647 default: 1648 break; 1649 } 1650 } 1651} 1652 1653static void 1654parse_number(void) 1655{ 1656 1657 unreadch(); 1658 push_number(readnumber(&bmachine.readstack[bmachine.readsp], 1659 bmachine.ibase)); 1660} 1661 1662static void 1663unknown(void) 1664{ 1665 int ch = bmachine.readstack[bmachine.readsp].lastchar; 1666 warnx("%c (0%o) is unimplemented", ch, ch); 1667} 1668 1669static void 1670eval_string(char *p) 1671{ 1672 int ch; 1673 1674 if (bmachine.readsp > 0) { 1675 /* Check for tail call. Do not recurse in that case. */ 1676 ch = readch(); 1677 if (ch == EOF) { 1678 src_free(); 1679 src_setstring(&bmachine.readstack[bmachine.readsp], p); 1680 return; 1681 } else 1682 unreadch(); 1683 } 1684 if (bmachine.readsp == bmachine.readstack_sz - 1) { 1685 size_t newsz = bmachine.readstack_sz * 2; 1686 struct source *stack; 1687 stack = realloc(bmachine.readstack, newsz * 1688 sizeof(struct source)); 1689 if (stack == NULL) 1690 err(1, "recursion too deep"); 1691 bmachine.readstack_sz = newsz; 1692 bmachine.readstack = stack; 1693 } 1694 src_setstring(&bmachine.readstack[++bmachine.readsp], p); 1695} 1696 1697static void 1698eval_line(void) 1699{ 1700 /* Always read from stdin */ 1701 struct source in; 1702 char *p; 1703 1704 clearerr(stdin); 1705 src_setstream(&in, stdin); 1706 p = (*in.vtable->readline)(&in); 1707 eval_string(p); 1708} 1709 1710static void 1711eval_tos(void) 1712{ 1713 char *p; 1714 1715 p = pop_string(); 1716 if (p == NULL) 1717 return; 1718 eval_string(p); 1719} 1720 1721void 1722eval(void) 1723{ 1724 int ch; 1725 1726 for (;;) { 1727 ch = readch(); 1728 if (ch == EOF) { 1729 if (bmachine.readsp == 0) 1730 return; 1731 src_free(); 1732 bmachine.readsp--; 1733 continue; 1734 } 1735#ifdef DEBUGGING 1736 fprintf(stderr, "# %c\n", ch); 1737 stack_print(stderr, &bmachine.stack, "* ", 1738 bmachine.obase); 1739 fprintf(stderr, "%zd =>\n", bmachine.readsp); 1740#endif 1741 1742 if (0 <= ch && ch < (signed)UCHAR_MAX) 1743 (*jump_table[ch])(); 1744 else 1745 warnx("internal error: opcode %d", ch); 1746 1747#ifdef DEBUGGING 1748 stack_print(stderr, &bmachine.stack, "* ", 1749 bmachine.obase); 1750 fprintf(stderr, "%zd ==\n", bmachine.readsp); 1751#endif 1752 } 1753} 1754