hexdump.c revision 91140
1/*- 2 * Copyright (c) 1986, 1988, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)subr_prf.c 8.3 (Berkeley) 1/21/94 39 * $FreeBSD: head/sys/kern/subr_prf.c 91140 2002-02-23 11:12:57Z tanimura $ 40 */ 41 42#include <sys/param.h> 43#include <sys/systm.h> 44#include <sys/lock.h> 45#include <sys/mutex.h> 46#include <sys/sx.h> 47#include <sys/kernel.h> 48#include <sys/msgbuf.h> 49#include <sys/malloc.h> 50#include <sys/proc.h> 51#include <sys/sysctl.h> 52#include <sys/tty.h> 53#include <sys/syslog.h> 54#include <sys/cons.h> 55#include <sys/uio.h> 56 57/* 58 * Note that stdarg.h and the ANSI style va_start macro is used for both 59 * ANSI and traditional C compilers. 60 */ 61#include <machine/stdarg.h> 62 63#define TOCONS 0x01 64#define TOTTY 0x02 65#define TOLOG 0x04 66 67/* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */ 68#define MAXNBUF (sizeof(quad_t) * NBBY + 1) 69 70struct putchar_arg { 71 int flags; 72 int pri; 73 struct tty *tty; 74}; 75 76struct snprintf_arg { 77 char *str; 78 size_t remain; 79}; 80 81extern int log_open; 82 83struct tty *constty; /* pointer to console "window" tty */ 84 85static void (*v_putc)(int) = cnputc; /* routine to putc on virtual console */ 86static void msglogchar(int c, int pri); 87static void msgaddchar(int c, void *dummy); 88static void putchar __P((int ch, void *arg)); 89static char *ksprintn __P((char *nbuf, u_long num, int base, int *len)); 90static char *ksprintqn __P((char *nbuf, u_quad_t num, int base, int *len)); 91static void snprintf_func __P((int ch, void *arg)); 92 93static int consintr = 1; /* Ok to handle console interrupts? */ 94static int msgbufmapped; /* Set when safe to use msgbuf */ 95int msgbuftrigger; 96 97/* 98 * Warn that a system table is full. 99 */ 100void 101tablefull(const char *tab) 102{ 103 104 log(LOG_ERR, "%s: table is full\n", tab); 105} 106 107/* 108 * Uprintf prints to the controlling terminal for the current process. 109 * It may block if the tty queue is overfull. No message is printed if 110 * the queue does not clear in a reasonable time. 111 */ 112int 113uprintf(const char *fmt, ...) 114{ 115 struct thread *td = curthread; 116 struct proc *p = td->td_proc; 117 va_list ap; 118 struct putchar_arg pca; 119 int retval; 120 121 if (td == NULL || td == PCPU_GET(idlethread)) 122 return (0); 123 124 p = td->td_proc; 125 PROC_LOCK(p); 126 if ((p->p_flag & P_CONTROLT) == 0) { 127 PROC_UNLOCK(p); 128 return (0); 129 } 130 SESS_LOCK(p->p_session); 131 pca.tty = p->p_session->s_ttyp; 132 SESS_UNLOCK(p->p_session); 133 PROC_UNLOCK(p); 134 if (pca.tty == NULL) 135 return (0); 136 pca.flags = TOTTY; 137 va_start(ap, fmt); 138 retval = kvprintf(fmt, putchar, &pca, 10, ap); 139 va_end(ap); 140 141 return (retval); 142} 143 144/* 145 * tprintf prints on the controlling terminal associated 146 * with the given session, possibly to the log as well. 147 */ 148void 149tprintf(struct proc *p, int pri, const char *fmt, ...) 150{ 151 struct tty *tp = NULL; 152 int flags = 0, shld = 0; 153 va_list ap; 154 struct putchar_arg pca; 155 int retval; 156 157 if (pri != -1) 158 flags |= TOLOG; 159 if (p != NULL) { 160 PGRPSESS_XLOCK(); 161 PROC_LOCK(p); 162 if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) { 163 SESS_LOCK(p->p_session); 164 SESSHOLD(p->p_session); 165 tp = p->p_session->s_ttyp; 166 SESS_UNLOCK(p->p_session); 167 PROC_UNLOCK(p); 168 shld++; 169 if (ttycheckoutq(tp, 0)) 170 flags |= TOTTY; 171 else 172 tp = NULL; 173 } else 174 PROC_UNLOCK(p); 175 PGRPSESS_XUNLOCK(); 176 } 177 pca.pri = pri; 178 pca.tty = tp; 179 pca.flags = flags; 180 va_start(ap, fmt); 181 retval = kvprintf(fmt, putchar, &pca, 10, ap); 182 va_end(ap); 183 if (shld) { 184 PGRPSESS_XLOCK(); 185 SESS_LOCK(p->p_session); 186 SESSRELE(p->p_session); 187 SESS_UNLOCK(p->p_session); 188 PGRPSESS_XUNLOCK(); 189 } 190 msgbuftrigger = 1; 191} 192 193/* 194 * Ttyprintf displays a message on a tty; it should be used only by 195 * the tty driver, or anything that knows the underlying tty will not 196 * be revoke(2)'d away. Other callers should use tprintf. 197 */ 198int 199ttyprintf(struct tty *tp, const char *fmt, ...) 200{ 201 va_list ap; 202 struct putchar_arg pca; 203 int retval; 204 205 va_start(ap, fmt); 206 pca.tty = tp; 207 pca.flags = TOTTY; 208 retval = kvprintf(fmt, putchar, &pca, 10, ap); 209 va_end(ap); 210 return (retval); 211} 212 213/* 214 * Log writes to the log buffer, and guarantees not to sleep (so can be 215 * called by interrupt routines). If there is no process reading the 216 * log yet, it writes to the console also. 217 */ 218void 219log(int level, const char *fmt, ...) 220{ 221 va_list ap; 222 int retval; 223 struct putchar_arg pca; 224 225 pca.tty = NULL; 226 pca.pri = level; 227 pca.flags = log_open ? TOLOG : TOCONS; 228 229 va_start(ap, fmt); 230 retval = kvprintf(fmt, putchar, &pca, 10, ap); 231 va_end(ap); 232 233 msgbuftrigger = 1; 234} 235 236#define CONSCHUNK 128 237 238void 239log_console(struct uio *uio) 240{ 241 int c, i, error, iovlen, nl; 242 struct uio muio; 243 struct iovec *miov = NULL; 244 char *consbuffer; 245 int pri; 246 247 pri = LOG_INFO | LOG_CONSOLE; 248 muio = *uio; 249 iovlen = uio->uio_iovcnt * sizeof (struct iovec); 250 MALLOC(miov, struct iovec *, iovlen, M_TEMP, M_WAITOK); 251 MALLOC(consbuffer, char *, CONSCHUNK, M_TEMP, M_WAITOK); 252 bcopy((caddr_t)muio.uio_iov, (caddr_t)miov, iovlen); 253 muio.uio_iov = miov; 254 uio = &muio; 255 256 nl = 0; 257 while (uio->uio_resid > 0) { 258 c = imin(uio->uio_resid, CONSCHUNK); 259 error = uiomove(consbuffer, c, uio); 260 if (error != 0) 261 return; 262 for (i = 0; i < c; i++) { 263 msglogchar(consbuffer[i], pri); 264 if (consbuffer[i] == '\n') 265 nl = 1; 266 else 267 nl = 0; 268 } 269 } 270 if (!nl) 271 msglogchar('\n', pri); 272 msgbuftrigger = 1; 273 FREE(miov, M_TEMP); 274 FREE(consbuffer, M_TEMP); 275 return; 276} 277 278int 279printf(const char *fmt, ...) 280{ 281 va_list ap; 282 int savintr; 283 struct putchar_arg pca; 284 int retval; 285 286 savintr = consintr; /* disable interrupts */ 287 consintr = 0; 288 va_start(ap, fmt); 289 pca.tty = NULL; 290 pca.flags = TOCONS | TOLOG; 291 pca.pri = -1; 292 retval = kvprintf(fmt, putchar, &pca, 10, ap); 293 va_end(ap); 294 if (!panicstr) 295 msgbuftrigger = 1; 296 consintr = savintr; /* reenable interrupts */ 297 return (retval); 298} 299 300int 301vprintf(const char *fmt, va_list ap) 302{ 303 int savintr; 304 struct putchar_arg pca; 305 int retval; 306 307 savintr = consintr; /* disable interrupts */ 308 consintr = 0; 309 pca.tty = NULL; 310 pca.flags = TOCONS | TOLOG; 311 pca.pri = -1; 312 retval = kvprintf(fmt, putchar, &pca, 10, ap); 313 if (!panicstr) 314 msgbuftrigger = 1; 315 consintr = savintr; /* reenable interrupts */ 316 return (retval); 317} 318 319/* 320 * Print a character on console or users terminal. If destination is 321 * the console then the last bunch of characters are saved in msgbuf for 322 * inspection later. 323 */ 324static void 325putchar(int c, void *arg) 326{ 327 struct putchar_arg *ap = (struct putchar_arg*) arg; 328 int flags = ap->flags; 329 struct tty *tp = ap->tty; 330 if (panicstr) 331 constty = NULL; 332 if ((flags & TOCONS) && tp == NULL && constty) { 333 tp = constty; 334 flags |= TOTTY; 335 } 336 if ((flags & TOTTY) && tp && tputchar(c, tp) < 0 && 337 (flags & TOCONS) && tp == constty) 338 constty = NULL; 339 if ((flags & TOLOG)) 340 msglogchar(c, ap->pri); 341 if ((flags & TOCONS) && constty == NULL && c != '\0') 342 (*v_putc)(c); 343} 344 345/* 346 * Scaled down version of sprintf(3). 347 */ 348int 349sprintf(char *buf, const char *cfmt, ...) 350{ 351 int retval; 352 va_list ap; 353 354 va_start(ap, cfmt); 355 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap); 356 buf[retval] = '\0'; 357 va_end(ap); 358 return (retval); 359} 360 361/* 362 * Scaled down version of vsprintf(3). 363 */ 364int 365vsprintf(char *buf, const char *cfmt, va_list ap) 366{ 367 int retval; 368 369 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap); 370 buf[retval] = '\0'; 371 return (retval); 372} 373 374/* 375 * Scaled down version of snprintf(3). 376 */ 377int 378snprintf(char *str, size_t size, const char *format, ...) 379{ 380 int retval; 381 va_list ap; 382 383 va_start(ap, format); 384 retval = vsnprintf(str, size, format, ap); 385 va_end(ap); 386 return(retval); 387} 388 389/* 390 * Scaled down version of vsnprintf(3). 391 */ 392int 393vsnprintf(char *str, size_t size, const char *format, va_list ap) 394{ 395 struct snprintf_arg info; 396 int retval; 397 398 info.str = str; 399 info.remain = size; 400 retval = kvprintf(format, snprintf_func, &info, 10, ap); 401 if (info.remain >= 1) 402 *info.str++ = '\0'; 403 return (retval); 404} 405 406static void 407snprintf_func(int ch, void *arg) 408{ 409 struct snprintf_arg *const info = arg; 410 411 if (info->remain >= 2) { 412 *info->str++ = ch; 413 info->remain--; 414 } 415} 416 417/* 418 * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse 419 * order; return an optional length and a pointer to the last character 420 * written in the buffer (i.e., the first character of the string). 421 * The buffer pointed to by `nbuf' must have length >= MAXNBUF. 422 */ 423static char * 424ksprintn(nbuf, ul, base, lenp) 425 char *nbuf; 426 u_long ul; 427 int base, *lenp; 428{ 429 char *p; 430 431 p = nbuf; 432 *p = '\0'; 433 do { 434 *++p = hex2ascii(ul % base); 435 } while (ul /= base); 436 if (lenp) 437 *lenp = p - nbuf; 438 return (p); 439} 440/* ksprintn, but for a quad_t. */ 441static char * 442ksprintqn(nbuf, uq, base, lenp) 443 char *nbuf; 444 u_quad_t uq; 445 int base, *lenp; 446{ 447 char *p; 448 449 p = nbuf; 450 *p = '\0'; 451 do { 452 *++p = hex2ascii(uq % base); 453 } while (uq /= base); 454 if (lenp) 455 *lenp = p - nbuf; 456 return (p); 457} 458 459/* 460 * Scaled down version of printf(3). 461 * 462 * Two additional formats: 463 * 464 * The format %b is supported to decode error registers. 465 * Its usage is: 466 * 467 * printf("reg=%b\n", regval, "<base><arg>*"); 468 * 469 * where <base> is the output base expressed as a control character, e.g. 470 * \10 gives octal; \20 gives hex. Each arg is a sequence of characters, 471 * the first of which gives the bit number to be inspected (origin 1), and 472 * the next characters (up to a control character, i.e. a character <= 32), 473 * give the name of the register. Thus: 474 * 475 * kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n"); 476 * 477 * would produce output: 478 * 479 * reg=3<BITTWO,BITONE> 480 * 481 * XXX: %D -- Hexdump, takes pointer and separator string: 482 * ("%6D", ptr, ":") -> XX:XX:XX:XX:XX:XX 483 * ("%*D", len, ptr, " " -> XX XX XX XX ... 484 */ 485int 486kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap) 487{ 488#define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; } 489 char nbuf[MAXNBUF]; 490 char *p, *q, *d; 491 u_char *up; 492 int ch, n; 493 u_long ul; 494 u_quad_t uq; 495 int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot; 496 int dwidth; 497 char padc; 498 int retval = 0; 499 500 ul = 0; 501 uq = 0; 502 if (!func) 503 d = (char *) arg; 504 else 505 d = NULL; 506 507 if (fmt == NULL) 508 fmt = "(fmt null)\n"; 509 510 if (radix < 2 || radix > 36) 511 radix = 10; 512 513 for (;;) { 514 padc = ' '; 515 width = 0; 516 while ((ch = (u_char)*fmt++) != '%') { 517 if (ch == '\0') 518 return (retval); 519 PCHAR(ch); 520 } 521 qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0; 522 sign = 0; dot = 0; dwidth = 0; 523reswitch: switch (ch = (u_char)*fmt++) { 524 case '.': 525 dot = 1; 526 goto reswitch; 527 case '#': 528 sharpflag = 1; 529 goto reswitch; 530 case '+': 531 sign = 1; 532 goto reswitch; 533 case '-': 534 ladjust = 1; 535 goto reswitch; 536 case '%': 537 PCHAR(ch); 538 break; 539 case '*': 540 if (!dot) { 541 width = va_arg(ap, int); 542 if (width < 0) { 543 ladjust = !ladjust; 544 width = -width; 545 } 546 } else { 547 dwidth = va_arg(ap, int); 548 } 549 goto reswitch; 550 case '0': 551 if (!dot) { 552 padc = '0'; 553 goto reswitch; 554 } 555 case '1': case '2': case '3': case '4': 556 case '5': case '6': case '7': case '8': case '9': 557 for (n = 0;; ++fmt) { 558 n = n * 10 + ch - '0'; 559 ch = *fmt; 560 if (ch < '0' || ch > '9') 561 break; 562 } 563 if (dot) 564 dwidth = n; 565 else 566 width = n; 567 goto reswitch; 568 case 'b': 569 ul = va_arg(ap, int); 570 p = va_arg(ap, char *); 571 for (q = ksprintn(nbuf, ul, *p++, NULL); *q;) 572 PCHAR(*q--); 573 574 if (!ul) 575 break; 576 577 for (tmp = 0; *p;) { 578 n = *p++; 579 if (ul & (1 << (n - 1))) { 580 PCHAR(tmp ? ',' : '<'); 581 for (; (n = *p) > ' '; ++p) 582 PCHAR(n); 583 tmp = 1; 584 } else 585 for (; *p > ' '; ++p) 586 continue; 587 } 588 if (tmp) 589 PCHAR('>'); 590 break; 591 case 'c': 592 PCHAR(va_arg(ap, int)); 593 break; 594 case 'D': 595 up = va_arg(ap, u_char *); 596 p = va_arg(ap, char *); 597 if (!width) 598 width = 16; 599 while(width--) { 600 PCHAR(hex2ascii(*up >> 4)); 601 PCHAR(hex2ascii(*up & 0x0f)); 602 up++; 603 if (width) 604 for (q=p;*q;q++) 605 PCHAR(*q); 606 } 607 break; 608 case 'd': 609 if (qflag) 610 uq = va_arg(ap, quad_t); 611 else if (lflag) 612 ul = va_arg(ap, long); 613 else 614 ul = va_arg(ap, int); 615 sign = 1; 616 base = 10; 617 goto number; 618 case 'l': 619 if (lflag) { 620 lflag = 0; 621 qflag = 1; 622 } else 623 lflag = 1; 624 goto reswitch; 625 case 'o': 626 if (qflag) 627 uq = va_arg(ap, u_quad_t); 628 else if (lflag) 629 ul = va_arg(ap, u_long); 630 else 631 ul = va_arg(ap, u_int); 632 base = 8; 633 goto nosign; 634 case 'p': 635 ul = (uintptr_t)va_arg(ap, void *); 636 base = 16; 637 sharpflag = (width == 0); 638 goto nosign; 639 case 'q': 640 qflag = 1; 641 goto reswitch; 642 case 'n': 643 case 'r': 644 if (qflag) 645 uq = va_arg(ap, u_quad_t); 646 else if (lflag) 647 ul = va_arg(ap, u_long); 648 else 649 ul = sign ? 650 (u_long)va_arg(ap, int) : va_arg(ap, u_int); 651 base = radix; 652 goto number; 653 case 's': 654 p = va_arg(ap, char *); 655 if (p == NULL) 656 p = "(null)"; 657 if (!dot) 658 n = strlen (p); 659 else 660 for (n = 0; n < dwidth && p[n]; n++) 661 continue; 662 663 width -= n; 664 665 if (!ladjust && width > 0) 666 while (width--) 667 PCHAR(padc); 668 while (n--) 669 PCHAR(*p++); 670 if (ladjust && width > 0) 671 while (width--) 672 PCHAR(padc); 673 break; 674 case 'u': 675 if (qflag) 676 uq = va_arg(ap, u_quad_t); 677 else if (lflag) 678 ul = va_arg(ap, u_long); 679 else 680 ul = va_arg(ap, u_int); 681 base = 10; 682 goto nosign; 683 case 'x': 684 case 'X': 685 if (qflag) 686 uq = va_arg(ap, u_quad_t); 687 else if (lflag) 688 ul = va_arg(ap, u_long); 689 else 690 ul = va_arg(ap, u_int); 691 base = 16; 692 goto nosign; 693 case 'z': 694 if (qflag) 695 uq = va_arg(ap, u_quad_t); 696 else if (lflag) 697 ul = va_arg(ap, u_long); 698 else 699 ul = sign ? 700 (u_long)va_arg(ap, int) : va_arg(ap, u_int); 701 base = 16; 702 goto number; 703nosign: sign = 0; 704number: 705 if (qflag) { 706 if (sign && (quad_t)uq < 0) { 707 neg = 1; 708 uq = -(quad_t)uq; 709 } 710 p = ksprintqn(nbuf, uq, base, &tmp); 711 } else { 712 if (sign && (long)ul < 0) { 713 neg = 1; 714 ul = -(long)ul; 715 } 716 p = ksprintn(nbuf, ul, base, &tmp); 717 } 718 if (sharpflag && (qflag ? uq != 0 : ul != 0)) { 719 if (base == 8) 720 tmp++; 721 else if (base == 16) 722 tmp += 2; 723 } 724 if (neg) 725 tmp++; 726 727 if (!ladjust && width && (width -= tmp) > 0) 728 while (width--) 729 PCHAR(padc); 730 if (neg) 731 PCHAR('-'); 732 if (sharpflag && (qflag ? uq != 0 : ul != 0)) { 733 if (base == 8) { 734 PCHAR('0'); 735 } else if (base == 16) { 736 PCHAR('0'); 737 PCHAR('x'); 738 } 739 } 740 741 while (*p) 742 PCHAR(*p--); 743 744 if (ladjust && width && (width -= tmp) > 0) 745 while (width--) 746 PCHAR(padc); 747 748 break; 749 default: 750 PCHAR('%'); 751 if (lflag) 752 PCHAR('l'); 753 PCHAR(ch); 754 break; 755 } 756 } 757#undef PCHAR 758} 759 760/* 761 * Put character in log buffer with a particular priority. 762 */ 763static void 764msglogchar(int c, int pri) 765{ 766 static int lastpri = -1; 767 static int dangling; 768 char nbuf[MAXNBUF]; 769 char *p; 770 771 if (!msgbufmapped) 772 return; 773 if (c == '\0' || c == '\r') 774 return; 775 if (pri != -1 && pri != lastpri) { 776 if (dangling) { 777 msgaddchar('\n', NULL); 778 dangling = 0; 779 } 780 msgaddchar('<', NULL); 781 for (p = ksprintn(nbuf, (u_long)pri, 10, NULL); *p;) 782 msgaddchar(*p--, NULL); 783 msgaddchar('>', NULL); 784 lastpri = pri; 785 } 786 msgaddchar(c, NULL); 787 if (c == '\n') { 788 dangling = 0; 789 lastpri = -1; 790 } else { 791 dangling = 1; 792 } 793} 794 795/* 796 * Put char in log buffer 797 */ 798static void 799msgaddchar(int c, void *dummy) 800{ 801 struct msgbuf *mbp; 802 803 if (!msgbufmapped) 804 return; 805 mbp = msgbufp; 806 mbp->msg_ptr[mbp->msg_bufx++] = c; 807 if (mbp->msg_bufx >= mbp->msg_size) 808 mbp->msg_bufx = 0; 809 /* If the buffer is full, keep the most recent data. */ 810 if (mbp->msg_bufr == mbp->msg_bufx) { 811 if (++mbp->msg_bufr >= mbp->msg_size) 812 mbp->msg_bufr = 0; 813 } 814} 815 816static void 817msgbufcopy(struct msgbuf *oldp) 818{ 819 int pos; 820 821 pos = oldp->msg_bufr; 822 while (pos != oldp->msg_bufx) { 823 msglogchar(oldp->msg_ptr[pos], -1); 824 if (++pos >= oldp->msg_size) 825 pos = 0; 826 } 827} 828 829void 830msgbufinit(void *ptr, size_t size) 831{ 832 char *cp; 833 static struct msgbuf *oldp = NULL; 834 835 size -= sizeof(*msgbufp); 836 cp = (char *)ptr; 837 msgbufp = (struct msgbuf *) (cp + size); 838 if (msgbufp->msg_magic != MSG_MAGIC || msgbufp->msg_size != size || 839 msgbufp->msg_bufx >= size || msgbufp->msg_bufr >= size) { 840 bzero(cp, size); 841 bzero(msgbufp, sizeof(*msgbufp)); 842 msgbufp->msg_magic = MSG_MAGIC; 843 msgbufp->msg_size = (char *)msgbufp - cp; 844 } 845 msgbufp->msg_ptr = cp; 846 if (msgbufmapped && oldp != msgbufp) 847 msgbufcopy(oldp); 848 msgbufmapped = 1; 849 oldp = msgbufp; 850} 851 852SYSCTL_DECL(_security_bsd); 853 854static int unprivileged_read_msgbuf = 1; 855SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_read_msgbuf, 856 CTLFLAG_RW, &unprivileged_read_msgbuf, 0, 857 "Unprivileged processes may read the kernel message buffer"); 858 859/* Sysctls for accessing/clearing the msgbuf */ 860static int 861sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS) 862{ 863 int error; 864 865 if (!unprivileged_read_msgbuf) { 866 error = suser_td(req->td); 867 if (error) 868 return (error); 869 } 870 871 /* 872 * Unwind the buffer, so that it's linear (possibly starting with 873 * some initial nulls). 874 */ 875 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr + msgbufp->msg_bufx, 876 msgbufp->msg_size - msgbufp->msg_bufx, req); 877 if (error) 878 return (error); 879 if (msgbufp->msg_bufx > 0) { 880 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr, 881 msgbufp->msg_bufx, req); 882 } 883 return (error); 884} 885 886SYSCTL_PROC(_kern, OID_AUTO, msgbuf, CTLTYPE_STRING | CTLFLAG_RD, 887 0, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer"); 888 889static int msgbuf_clear; 890 891static int 892sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS) 893{ 894 int error; 895 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req); 896 if (!error && req->newptr) { 897 /* Clear the buffer and reset write pointer */ 898 bzero(msgbufp->msg_ptr, msgbufp->msg_size); 899 msgbufp->msg_bufr = msgbufp->msg_bufx = 0; 900 msgbuf_clear = 0; 901 } 902 return (error); 903} 904 905SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear, 906 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, &msgbuf_clear, 0, 907 sysctl_kern_msgbuf_clear, "I", "Clear kernel message buffer"); 908 909#include "opt_ddb.h" 910#ifdef DDB 911#include <ddb/ddb.h> 912 913DB_SHOW_COMMAND(msgbuf, db_show_msgbuf) 914{ 915 int i, j; 916 917 if (!msgbufmapped) { 918 db_printf("msgbuf not mapped yet\n"); 919 return; 920 } 921 db_printf("msgbufp = %p\n", msgbufp); 922 db_printf("magic = %x, size = %d, r= %d, w = %d, ptr = %p\n", 923 msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_bufr, 924 msgbufp->msg_bufx, msgbufp->msg_ptr); 925 for (i = 0; i < msgbufp->msg_size; i++) { 926 j = (i + msgbufp->msg_bufr) % msgbufp->msg_size; 927 db_printf("%c", msgbufp->msg_ptr[j]); 928 } 929 db_printf("\n"); 930} 931 932#endif /* DDB */ 933