hexdump.c revision 90490
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 90490 2002-02-10 22:04:44Z phk $ 40 */ 41 42#include <sys/param.h> 43#include <sys/systm.h> 44#include <sys/kernel.h> 45#include <sys/msgbuf.h> 46#include <sys/malloc.h> 47#include <sys/proc.h> 48#include <sys/sysctl.h> 49#include <sys/tty.h> 50#include <sys/syslog.h> 51#include <sys/cons.h> 52#include <sys/uio.h> 53 54/* 55 * Note that stdarg.h and the ANSI style va_start macro is used for both 56 * ANSI and traditional C compilers. 57 */ 58#include <machine/stdarg.h> 59 60#define TOCONS 0x01 61#define TOTTY 0x02 62#define TOLOG 0x04 63 64/* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */ 65#define MAXNBUF (sizeof(quad_t) * NBBY + 1) 66 67struct putchar_arg { 68 int flags; 69 int pri; 70 struct tty *tty; 71}; 72 73struct snprintf_arg { 74 char *str; 75 size_t remain; 76}; 77 78extern int log_open; 79 80struct tty *constty; /* pointer to console "window" tty */ 81 82static void (*v_putc)(int) = cnputc; /* routine to putc on virtual console */ 83static void msglogchar(int c, int pri); 84static void msgaddchar(int c, void *dummy); 85static void putchar __P((int ch, void *arg)); 86static char *ksprintn __P((char *nbuf, u_long num, int base, int *len)); 87static char *ksprintqn __P((char *nbuf, u_quad_t num, int base, int *len)); 88static void snprintf_func __P((int ch, void *arg)); 89 90static int consintr = 1; /* Ok to handle console interrupts? */ 91static int msgbufmapped; /* Set when safe to use msgbuf */ 92int msgbuftrigger; 93 94/* 95 * Warn that a system table is full. 96 */ 97void 98tablefull(const char *tab) 99{ 100 101 log(LOG_ERR, "%s: table is full\n", tab); 102} 103 104/* 105 * Uprintf prints to the controlling terminal for the current process. 106 * It may block if the tty queue is overfull. No message is printed if 107 * the queue does not clear in a reasonable time. 108 */ 109int 110uprintf(const char *fmt, ...) 111{ 112 struct thread *td = curthread; 113 struct proc *p = td->td_proc; 114 va_list ap; 115 struct putchar_arg pca; 116 int retval = 0; 117 118 if (td && td != PCPU_GET(idlethread) && p->p_flag & P_CONTROLT && 119 p->p_session->s_ttyvp) { 120 va_start(ap, fmt); 121 pca.tty = p->p_session->s_ttyp; 122 pca.flags = TOTTY; 123 retval = kvprintf(fmt, putchar, &pca, 10, ap); 124 va_end(ap); 125 } 126 return (retval); 127} 128 129/* 130 * tprintf prints on the controlling terminal associated 131 * with the given session, possibly to the log as well. 132 */ 133void 134tprintf(struct proc *p, int pri, const char *fmt, ...) 135{ 136 struct tty *tp = NULL; 137 int flags = 0, shld = 0; 138 va_list ap; 139 struct putchar_arg pca; 140 int retval; 141 142 if (pri != -1) 143 flags |= TOLOG; 144 if (p && p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) { 145 SESSHOLD(p->p_session); 146 shld++; 147 if (ttycheckoutq(p->p_session->s_ttyp, 0)) { 148 flags |= TOTTY; 149 tp = p->p_session->s_ttyp; 150 } 151 } 152 pca.pri = pri; 153 pca.tty = tp; 154 pca.flags = flags; 155 va_start(ap, fmt); 156 retval = kvprintf(fmt, putchar, &pca, 10, ap); 157 va_end(ap); 158 if (shld) 159 SESSRELE(p->p_session); 160 msgbuftrigger = 1; 161} 162 163/* 164 * Ttyprintf displays a message on a tty; it should be used only by 165 * the tty driver, or anything that knows the underlying tty will not 166 * be revoke(2)'d away. Other callers should use tprintf. 167 */ 168int 169ttyprintf(struct tty *tp, const char *fmt, ...) 170{ 171 va_list ap; 172 struct putchar_arg pca; 173 int retval; 174 175 va_start(ap, fmt); 176 pca.tty = tp; 177 pca.flags = TOTTY; 178 retval = kvprintf(fmt, putchar, &pca, 10, ap); 179 va_end(ap); 180 return (retval); 181} 182 183/* 184 * Log writes to the log buffer, and guarantees not to sleep (so can be 185 * called by interrupt routines). If there is no process reading the 186 * log yet, it writes to the console also. 187 */ 188void 189log(int level, const char *fmt, ...) 190{ 191 va_list ap; 192 int retval; 193 struct putchar_arg pca; 194 195 pca.tty = NULL; 196 pca.pri = level; 197 pca.flags = log_open ? TOLOG : TOCONS; 198 199 va_start(ap, fmt); 200 retval = kvprintf(fmt, putchar, &pca, 10, ap); 201 va_end(ap); 202 203 msgbuftrigger = 1; 204} 205 206#define CONSCHUNK 128 207 208void 209log_console(struct uio *uio) 210{ 211 int c, i, error, iovlen, nl; 212 struct uio muio; 213 struct iovec *miov = NULL; 214 char *consbuffer; 215 int pri; 216 217 pri = LOG_INFO | LOG_CONSOLE; 218 muio = *uio; 219 iovlen = uio->uio_iovcnt * sizeof (struct iovec); 220 MALLOC(miov, struct iovec *, iovlen, M_TEMP, M_WAITOK); 221 MALLOC(consbuffer, char *, CONSCHUNK, M_TEMP, M_WAITOK); 222 bcopy((caddr_t)muio.uio_iov, (caddr_t)miov, iovlen); 223 muio.uio_iov = miov; 224 uio = &muio; 225 226 nl = 0; 227 while (uio->uio_resid > 0) { 228 c = imin(uio->uio_resid, CONSCHUNK); 229 error = uiomove(consbuffer, c, uio); 230 if (error != 0) 231 return; 232 for (i = 0; i < c; i++) { 233 msglogchar(consbuffer[i], pri); 234 if (consbuffer[i] == '\n') 235 nl = 1; 236 else 237 nl = 0; 238 } 239 } 240 if (!nl) 241 msglogchar('\n', pri); 242 msgbuftrigger = 1; 243 FREE(miov, M_TEMP); 244 FREE(consbuffer, M_TEMP); 245 return; 246} 247 248int 249printf(const char *fmt, ...) 250{ 251 va_list ap; 252 int savintr; 253 struct putchar_arg pca; 254 int retval; 255 256 savintr = consintr; /* disable interrupts */ 257 consintr = 0; 258 va_start(ap, fmt); 259 pca.tty = NULL; 260 pca.flags = TOCONS | TOLOG; 261 pca.pri = -1; 262 retval = kvprintf(fmt, putchar, &pca, 10, ap); 263 va_end(ap); 264 if (!panicstr) 265 msgbuftrigger = 1; 266 consintr = savintr; /* reenable interrupts */ 267 return (retval); 268} 269 270int 271vprintf(const char *fmt, va_list ap) 272{ 273 int savintr; 274 struct putchar_arg pca; 275 int retval; 276 277 savintr = consintr; /* disable interrupts */ 278 consintr = 0; 279 pca.tty = NULL; 280 pca.flags = TOCONS | TOLOG; 281 pca.pri = -1; 282 retval = kvprintf(fmt, putchar, &pca, 10, ap); 283 if (!panicstr) 284 msgbuftrigger = 1; 285 consintr = savintr; /* reenable interrupts */ 286 return (retval); 287} 288 289/* 290 * Print a character on console or users terminal. If destination is 291 * the console then the last bunch of characters are saved in msgbuf for 292 * inspection later. 293 */ 294static void 295putchar(int c, void *arg) 296{ 297 struct putchar_arg *ap = (struct putchar_arg*) arg; 298 int flags = ap->flags; 299 struct tty *tp = ap->tty; 300 if (panicstr) 301 constty = NULL; 302 if ((flags & TOCONS) && tp == NULL && constty) { 303 tp = constty; 304 flags |= TOTTY; 305 } 306 if ((flags & TOTTY) && tp && tputchar(c, tp) < 0 && 307 (flags & TOCONS) && tp == constty) 308 constty = NULL; 309 if ((flags & TOLOG)) 310 msglogchar(c, ap->pri); 311 if ((flags & TOCONS) && constty == NULL && c != '\0') 312 (*v_putc)(c); 313} 314 315/* 316 * Scaled down version of sprintf(3). 317 */ 318int 319sprintf(char *buf, const char *cfmt, ...) 320{ 321 int retval; 322 va_list ap; 323 324 va_start(ap, cfmt); 325 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap); 326 buf[retval] = '\0'; 327 va_end(ap); 328 return (retval); 329} 330 331/* 332 * Scaled down version of vsprintf(3). 333 */ 334int 335vsprintf(char *buf, const char *cfmt, va_list ap) 336{ 337 int retval; 338 339 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap); 340 buf[retval] = '\0'; 341 return (retval); 342} 343 344/* 345 * Scaled down version of snprintf(3). 346 */ 347int 348snprintf(char *str, size_t size, const char *format, ...) 349{ 350 int retval; 351 va_list ap; 352 353 va_start(ap, format); 354 retval = vsnprintf(str, size, format, ap); 355 va_end(ap); 356 return(retval); 357} 358 359/* 360 * Scaled down version of vsnprintf(3). 361 */ 362int 363vsnprintf(char *str, size_t size, const char *format, va_list ap) 364{ 365 struct snprintf_arg info; 366 int retval; 367 368 info.str = str; 369 info.remain = size; 370 retval = kvprintf(format, snprintf_func, &info, 10, ap); 371 if (info.remain >= 1) 372 *info.str++ = '\0'; 373 return (retval); 374} 375 376static void 377snprintf_func(int ch, void *arg) 378{ 379 struct snprintf_arg *const info = arg; 380 381 if (info->remain >= 2) { 382 *info->str++ = ch; 383 info->remain--; 384 } 385} 386 387/* 388 * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse 389 * order; return an optional length and a pointer to the last character 390 * written in the buffer (i.e., the first character of the string). 391 * The buffer pointed to by `nbuf' must have length >= MAXNBUF. 392 */ 393static char * 394ksprintn(nbuf, ul, base, lenp) 395 char *nbuf; 396 u_long ul; 397 int base, *lenp; 398{ 399 char *p; 400 401 p = nbuf; 402 *p = '\0'; 403 do { 404 *++p = hex2ascii(ul % base); 405 } while (ul /= base); 406 if (lenp) 407 *lenp = p - nbuf; 408 return (p); 409} 410/* ksprintn, but for a quad_t. */ 411static char * 412ksprintqn(nbuf, uq, base, lenp) 413 char *nbuf; 414 u_quad_t uq; 415 int base, *lenp; 416{ 417 char *p; 418 419 p = nbuf; 420 *p = '\0'; 421 do { 422 *++p = hex2ascii(uq % base); 423 } while (uq /= base); 424 if (lenp) 425 *lenp = p - nbuf; 426 return (p); 427} 428 429/* 430 * Scaled down version of printf(3). 431 * 432 * Two additional formats: 433 * 434 * The format %b is supported to decode error registers. 435 * Its usage is: 436 * 437 * printf("reg=%b\n", regval, "<base><arg>*"); 438 * 439 * where <base> is the output base expressed as a control character, e.g. 440 * \10 gives octal; \20 gives hex. Each arg is a sequence of characters, 441 * the first of which gives the bit number to be inspected (origin 1), and 442 * the next characters (up to a control character, i.e. a character <= 32), 443 * give the name of the register. Thus: 444 * 445 * kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n"); 446 * 447 * would produce output: 448 * 449 * reg=3<BITTWO,BITONE> 450 * 451 * XXX: %D -- Hexdump, takes pointer and separator string: 452 * ("%6D", ptr, ":") -> XX:XX:XX:XX:XX:XX 453 * ("%*D", len, ptr, " " -> XX XX XX XX ... 454 */ 455int 456kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap) 457{ 458#define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; } 459 char nbuf[MAXNBUF]; 460 char *p, *q, *d; 461 u_char *up; 462 int ch, n; 463 u_long ul; 464 u_quad_t uq; 465 int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot; 466 int dwidth; 467 char padc; 468 int retval = 0; 469 470 ul = 0; 471 uq = 0; 472 if (!func) 473 d = (char *) arg; 474 else 475 d = NULL; 476 477 if (fmt == NULL) 478 fmt = "(fmt null)\n"; 479 480 if (radix < 2 || radix > 36) 481 radix = 10; 482 483 for (;;) { 484 padc = ' '; 485 width = 0; 486 while ((ch = (u_char)*fmt++) != '%') { 487 if (ch == '\0') 488 return (retval); 489 PCHAR(ch); 490 } 491 qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0; 492 sign = 0; dot = 0; dwidth = 0; 493reswitch: switch (ch = (u_char)*fmt++) { 494 case '.': 495 dot = 1; 496 goto reswitch; 497 case '#': 498 sharpflag = 1; 499 goto reswitch; 500 case '+': 501 sign = 1; 502 goto reswitch; 503 case '-': 504 ladjust = 1; 505 goto reswitch; 506 case '%': 507 PCHAR(ch); 508 break; 509 case '*': 510 if (!dot) { 511 width = va_arg(ap, int); 512 if (width < 0) { 513 ladjust = !ladjust; 514 width = -width; 515 } 516 } else { 517 dwidth = va_arg(ap, int); 518 } 519 goto reswitch; 520 case '0': 521 if (!dot) { 522 padc = '0'; 523 goto reswitch; 524 } 525 case '1': case '2': case '3': case '4': 526 case '5': case '6': case '7': case '8': case '9': 527 for (n = 0;; ++fmt) { 528 n = n * 10 + ch - '0'; 529 ch = *fmt; 530 if (ch < '0' || ch > '9') 531 break; 532 } 533 if (dot) 534 dwidth = n; 535 else 536 width = n; 537 goto reswitch; 538 case 'b': 539 ul = va_arg(ap, int); 540 p = va_arg(ap, char *); 541 for (q = ksprintn(nbuf, ul, *p++, NULL); *q;) 542 PCHAR(*q--); 543 544 if (!ul) 545 break; 546 547 for (tmp = 0; *p;) { 548 n = *p++; 549 if (ul & (1 << (n - 1))) { 550 PCHAR(tmp ? ',' : '<'); 551 for (; (n = *p) > ' '; ++p) 552 PCHAR(n); 553 tmp = 1; 554 } else 555 for (; *p > ' '; ++p) 556 continue; 557 } 558 if (tmp) 559 PCHAR('>'); 560 break; 561 case 'c': 562 PCHAR(va_arg(ap, int)); 563 break; 564 case 'D': 565 up = va_arg(ap, u_char *); 566 p = va_arg(ap, char *); 567 if (!width) 568 width = 16; 569 while(width--) { 570 PCHAR(hex2ascii(*up >> 4)); 571 PCHAR(hex2ascii(*up & 0x0f)); 572 up++; 573 if (width) 574 for (q=p;*q;q++) 575 PCHAR(*q); 576 } 577 break; 578 case 'd': 579 if (qflag) 580 uq = va_arg(ap, quad_t); 581 else if (lflag) 582 ul = va_arg(ap, long); 583 else 584 ul = va_arg(ap, int); 585 sign = 1; 586 base = 10; 587 goto number; 588 case 'l': 589 if (lflag) { 590 lflag = 0; 591 qflag = 1; 592 } else 593 lflag = 1; 594 goto reswitch; 595 case 'o': 596 if (qflag) 597 uq = va_arg(ap, u_quad_t); 598 else if (lflag) 599 ul = va_arg(ap, u_long); 600 else 601 ul = va_arg(ap, u_int); 602 base = 8; 603 goto nosign; 604 case 'p': 605 ul = (uintptr_t)va_arg(ap, void *); 606 base = 16; 607 sharpflag = (width == 0); 608 goto nosign; 609 case 'q': 610 qflag = 1; 611 goto reswitch; 612 case 'n': 613 case 'r': 614 if (qflag) 615 uq = va_arg(ap, u_quad_t); 616 else if (lflag) 617 ul = va_arg(ap, u_long); 618 else 619 ul = sign ? 620 (u_long)va_arg(ap, int) : va_arg(ap, u_int); 621 base = radix; 622 goto number; 623 case 's': 624 p = va_arg(ap, char *); 625 if (p == NULL) 626 p = "(null)"; 627 if (!dot) 628 n = strlen (p); 629 else 630 for (n = 0; n < dwidth && p[n]; n++) 631 continue; 632 633 width -= n; 634 635 if (!ladjust && width > 0) 636 while (width--) 637 PCHAR(padc); 638 while (n--) 639 PCHAR(*p++); 640 if (ladjust && width > 0) 641 while (width--) 642 PCHAR(padc); 643 break; 644 case 'u': 645 if (qflag) 646 uq = va_arg(ap, u_quad_t); 647 else if (lflag) 648 ul = va_arg(ap, u_long); 649 else 650 ul = va_arg(ap, u_int); 651 base = 10; 652 goto nosign; 653 case 'x': 654 case 'X': 655 if (qflag) 656 uq = va_arg(ap, u_quad_t); 657 else if (lflag) 658 ul = va_arg(ap, u_long); 659 else 660 ul = va_arg(ap, u_int); 661 base = 16; 662 goto nosign; 663 case 'z': 664 if (qflag) 665 uq = va_arg(ap, u_quad_t); 666 else if (lflag) 667 ul = va_arg(ap, u_long); 668 else 669 ul = sign ? 670 (u_long)va_arg(ap, int) : va_arg(ap, u_int); 671 base = 16; 672 goto number; 673nosign: sign = 0; 674number: 675 if (qflag) { 676 if (sign && (quad_t)uq < 0) { 677 neg = 1; 678 uq = -(quad_t)uq; 679 } 680 p = ksprintqn(nbuf, uq, base, &tmp); 681 } else { 682 if (sign && (long)ul < 0) { 683 neg = 1; 684 ul = -(long)ul; 685 } 686 p = ksprintn(nbuf, ul, base, &tmp); 687 } 688 if (sharpflag && (qflag ? uq != 0 : ul != 0)) { 689 if (base == 8) 690 tmp++; 691 else if (base == 16) 692 tmp += 2; 693 } 694 if (neg) 695 tmp++; 696 697 if (!ladjust && width && (width -= tmp) > 0) 698 while (width--) 699 PCHAR(padc); 700 if (neg) 701 PCHAR('-'); 702 if (sharpflag && (qflag ? uq != 0 : ul != 0)) { 703 if (base == 8) { 704 PCHAR('0'); 705 } else if (base == 16) { 706 PCHAR('0'); 707 PCHAR('x'); 708 } 709 } 710 711 while (*p) 712 PCHAR(*p--); 713 714 if (ladjust && width && (width -= tmp) > 0) 715 while (width--) 716 PCHAR(padc); 717 718 break; 719 default: 720 PCHAR('%'); 721 if (lflag) 722 PCHAR('l'); 723 PCHAR(ch); 724 break; 725 } 726 } 727#undef PCHAR 728} 729 730/* 731 * Put character in log buffer with a particular priority. 732 */ 733static void 734msglogchar(int c, int pri) 735{ 736 static int lastpri = -1; 737 static int dangling; 738 char nbuf[MAXNBUF]; 739 char *p; 740 741 if (!msgbufmapped) 742 return; 743 if (c == '\0' || c == '\r') 744 return; 745 if (pri != -1 && pri != lastpri) { 746 if (dangling) { 747 msgaddchar('\n', NULL); 748 dangling = 0; 749 } 750 msgaddchar('<', NULL); 751 for (p = ksprintn(nbuf, (u_long)pri, 10, NULL); *p;) 752 msgaddchar(*p--, NULL); 753 msgaddchar('>', NULL); 754 lastpri = pri; 755 } 756 msgaddchar(c, NULL); 757 if (c == '\n') { 758 dangling = 0; 759 lastpri = -1; 760 } else { 761 dangling = 1; 762 } 763} 764 765/* 766 * Put char in log buffer 767 */ 768static void 769msgaddchar(int c, void *dummy) 770{ 771 struct msgbuf *mbp; 772 773 if (!msgbufmapped) 774 return; 775 mbp = msgbufp; 776 mbp->msg_ptr[mbp->msg_bufx++] = c; 777 if (mbp->msg_bufx >= mbp->msg_size) 778 mbp->msg_bufx = 0; 779 /* If the buffer is full, keep the most recent data. */ 780 if (mbp->msg_bufr == mbp->msg_bufx) { 781 if (++mbp->msg_bufr >= mbp->msg_size) 782 mbp->msg_bufr = 0; 783 } 784} 785 786static void 787msgbufcopy(struct msgbuf *oldp) 788{ 789 int pos; 790 791 pos = oldp->msg_bufr; 792 while (pos != oldp->msg_bufx) { 793 msglogchar(oldp->msg_ptr[pos], -1); 794 if (++pos >= oldp->msg_size) 795 pos = 0; 796 } 797} 798 799void 800msgbufinit(void *ptr, size_t size) 801{ 802 char *cp; 803 static struct msgbuf *oldp = NULL; 804 805 size -= sizeof(*msgbufp); 806 cp = (char *)ptr; 807 msgbufp = (struct msgbuf *) (cp + size); 808 if (msgbufp->msg_magic != MSG_MAGIC || msgbufp->msg_size != size || 809 msgbufp->msg_bufx >= size || msgbufp->msg_bufr >= size) { 810 bzero(cp, size); 811 bzero(msgbufp, sizeof(*msgbufp)); 812 msgbufp->msg_magic = MSG_MAGIC; 813 msgbufp->msg_size = (char *)msgbufp - cp; 814 } 815 msgbufp->msg_ptr = cp; 816 if (msgbufmapped && oldp != msgbufp) 817 msgbufcopy(oldp); 818 msgbufmapped = 1; 819 oldp = msgbufp; 820} 821 822SYSCTL_DECL(_security_bsd); 823 824static int unprivileged_read_msgbuf = 1; 825SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_read_msgbuf, 826 CTLFLAG_RW, &unprivileged_read_msgbuf, 0, 827 "Unprivileged processes may read the kernel message buffer"); 828 829/* Sysctls for accessing/clearing the msgbuf */ 830static int 831sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS) 832{ 833 int error; 834 835 if (!unprivileged_read_msgbuf) { 836 error = suser_td(req->td); 837 if (error) 838 return (error); 839 } 840 841 /* 842 * Unwind the buffer, so that it's linear (possibly starting with 843 * some initial nulls). 844 */ 845 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr + msgbufp->msg_bufx, 846 msgbufp->msg_size - msgbufp->msg_bufx, req); 847 if (error) 848 return (error); 849 if (msgbufp->msg_bufx > 0) { 850 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr, 851 msgbufp->msg_bufx, req); 852 } 853 return (error); 854} 855 856SYSCTL_PROC(_kern, OID_AUTO, msgbuf, CTLTYPE_STRING | CTLFLAG_RD, 857 0, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer"); 858 859static int msgbuf_clear; 860 861static int 862sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS) 863{ 864 int error; 865 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req); 866 if (!error && req->newptr) { 867 /* Clear the buffer and reset write pointer */ 868 bzero(msgbufp->msg_ptr, msgbufp->msg_size); 869 msgbufp->msg_bufr = msgbufp->msg_bufx = 0; 870 msgbuf_clear = 0; 871 } 872 return (error); 873} 874 875SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear, 876 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, &msgbuf_clear, 0, 877 sysctl_kern_msgbuf_clear, "I", "Clear kernel message buffer"); 878 879#include "opt_ddb.h" 880#ifdef DDB 881#include <ddb/ddb.h> 882 883DB_SHOW_COMMAND(msgbuf, db_show_msgbuf) 884{ 885 int i, j; 886 887 if (!msgbufmapped) { 888 db_printf("msgbuf not mapped yet\n"); 889 return; 890 } 891 db_printf("msgbufp = %p\n", msgbufp); 892 db_printf("magic = %x, size = %d, r= %d, w = %d, ptr = %p\n", 893 msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_bufr, 894 msgbufp->msg_bufx, msgbufp->msg_ptr); 895 for (i = 0; i < msgbufp->msg_size; i++) { 896 j = (i + msgbufp->msg_bufr) % msgbufp->msg_size; 897 db_printf("%c", msgbufp->msg_ptr[j]); 898 } 899 db_printf("\n"); 900} 901 902#endif /* DDB */ 903