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