diff options
author | Theo de Raadt <deraadt@cvs.openbsd.org> | 1995-10-18 08:53:40 +0000 |
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committer | Theo de Raadt <deraadt@cvs.openbsd.org> | 1995-10-18 08:53:40 +0000 |
commit | d6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch) | |
tree | ece253b876159b39c620e62b6c9b1174642e070e /lib/libkvm/kvm.c |
initial import of NetBSD tree
Diffstat (limited to 'lib/libkvm/kvm.c')
-rw-r--r-- | lib/libkvm/kvm.c | 552 |
1 files changed, 552 insertions, 0 deletions
diff --git a/lib/libkvm/kvm.c b/lib/libkvm/kvm.c new file mode 100644 index 00000000000..db1e91320b2 --- /dev/null +++ b/lib/libkvm/kvm.c @@ -0,0 +1,552 @@ +/*- + * Copyright (c) 1989, 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software developed by the Computer Systems + * Engineering group at Lawrence Berkeley Laboratory under DARPA contract + * BG 91-66 and contributed to Berkeley. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)kvm.c 8.2 (Berkeley) 2/13/94"; +#endif /* LIBC_SCCS and not lint */ + +#include <sys/param.h> +#include <sys/user.h> +#include <sys/proc.h> +#include <sys/ioctl.h> +#include <sys/stat.h> +#include <sys/sysctl.h> + +#include <vm/vm.h> +#include <vm/vm_param.h> +#include <vm/swap_pager.h> + +#include <machine/vmparam.h> + +#include <ctype.h> +#include <db.h> +#include <fcntl.h> +#include <kvm.h> +#include <limits.h> +#include <nlist.h> +#include <paths.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "kvm_private.h" + +static int kvm_dbopen __P((kvm_t *, const char *)); +static kvm_t *_kvm_open __P((kvm_t *, const char *, const char *, + const char *, int, char *)); + +char * +kvm_geterr(kd) + kvm_t *kd; +{ + return (kd->errbuf); +} + +#if __STDC__ +#include <stdarg.h> +#else +#include <varargs.h> +#endif + +/* + * Report an error using printf style arguments. "program" is kd->program + * on hard errors, and 0 on soft errors, so that under sun error emulation, + * only hard errors are printed out (otherwise, programs like gdb will + * generate tons of error messages when trying to access bogus pointers). + */ +void +#if __STDC__ +_kvm_err(kvm_t *kd, const char *program, const char *fmt, ...) +#else +_kvm_err(kd, program, fmt, va_alist) + kvm_t *kd; + char *program, *fmt; + va_dcl +#endif +{ + va_list ap; + +#ifdef __STDC__ + va_start(ap, fmt); +#else + va_start(ap); +#endif + if (program != NULL) { + (void)fprintf(stderr, "%s: ", program); + (void)vfprintf(stderr, fmt, ap); + (void)fputc('\n', stderr); + } else + (void)vsnprintf(kd->errbuf, + sizeof(kd->errbuf), (char *)fmt, ap); + + va_end(ap); +} + +void +#if __STDC__ +_kvm_syserr(kvm_t *kd, const char *program, const char *fmt, ...) +#else +_kvm_syserr(kd, program, fmt, va_alist) + kvm_t *kd; + char *program, *fmt; + va_dcl +#endif +{ + va_list ap; + register int n; + +#if __STDC__ + va_start(ap, fmt); +#else + va_start(ap); +#endif + if (program != NULL) { + (void)fprintf(stderr, "%s: ", program); + (void)vfprintf(stderr, fmt, ap); + (void)fprintf(stderr, ": %s\n", strerror(errno)); + } else { + register char *cp = kd->errbuf; + + (void)vsnprintf(cp, sizeof(kd->errbuf), (char *)fmt, ap); + n = strlen(cp); + (void)snprintf(&cp[n], sizeof(kd->errbuf) - n, ": %s", + strerror(errno)); + } + va_end(ap); +} + +void * +_kvm_malloc(kd, n) + register kvm_t *kd; + register size_t n; +{ + void *p; + + if ((p = malloc(n)) == NULL) + _kvm_err(kd, kd->program, strerror(errno)); + return (p); +} + +static kvm_t * +_kvm_open(kd, uf, mf, sf, flag, errout) + register kvm_t *kd; + const char *uf; + const char *mf; + const char *sf; + int flag; + char *errout; +{ + struct stat st; + + kd->db = 0; + kd->pmfd = -1; + kd->vmfd = -1; + kd->swfd = -1; + kd->nlfd = -1; + kd->procbase = 0; + kd->nbpg = getpagesize(); + kd->swapspc = 0; + kd->argspc = 0; + kd->argbuf = 0; + kd->argv = 0; + kd->vmst = 0; + kd->vm_page_buckets = 0; + + if (uf == 0) + uf = _PATH_UNIX; + else if (strlen(uf) >= MAXPATHLEN) { + _kvm_err(kd, kd->program, "exec file name too long"); + goto failed; + } + if (flag & ~O_RDWR) { + _kvm_err(kd, kd->program, "bad flags arg"); + goto failed; + } + if (mf == 0) + mf = _PATH_MEM; + if (sf == 0) + sf = _PATH_DRUM; + + if ((kd->pmfd = open(mf, flag, 0)) < 0) { + _kvm_syserr(kd, kd->program, "%s", mf); + goto failed; + } + if (fstat(kd->pmfd, &st) < 0) { + _kvm_syserr(kd, kd->program, "%s", mf); + goto failed; + } + if (S_ISCHR(st.st_mode)) { + /* + * If this is a character special device, then check that + * it's /dev/mem. If so, open kmem too. (Maybe we should + * make it work for either /dev/mem or /dev/kmem -- in either + * case you're working with a live kernel.) + */ + if (strcmp(mf, _PATH_MEM) != 0) { /* XXX */ + _kvm_err(kd, kd->program, + "%s: not physical memory device", mf); + goto failed; + } + if ((kd->vmfd = open(_PATH_KMEM, flag)) < 0) { + _kvm_syserr(kd, kd->program, "%s", _PATH_KMEM); + goto failed; + } + if ((kd->swfd = open(sf, flag, 0)) < 0) { + _kvm_syserr(kd, kd->program, "%s", sf); + goto failed; + } + /* + * Open kvm nlist database. We go ahead and do this + * here so that we don't have to hold on to the vmunix + * path name. Since a kvm application will surely do + * a kvm_nlist(), this probably won't be a wasted effort. + * If the database cannot be opened, open the namelist + * argument so we revert to slow nlist() calls. + */ + if (kvm_dbopen(kd, uf) < 0 && + (kd->nlfd = open(uf, O_RDONLY, 0)) < 0) { + _kvm_syserr(kd, kd->program, "%s", uf); + goto failed; + } + } else { + /* + * This is a crash dump. + * Initalize the virtual address translation machinery, + * but first setup the namelist fd. + */ + if ((kd->nlfd = open(uf, O_RDONLY, 0)) < 0) { + _kvm_syserr(kd, kd->program, "%s", uf); + goto failed; + } + if (_kvm_initvtop(kd) < 0) + goto failed; + } + return (kd); +failed: + /* + * Copy out the error if doing sane error semantics. + */ + if (errout != 0) + strcpy(errout, kd->errbuf); + (void)kvm_close(kd); + return (0); +} + +kvm_t * +kvm_openfiles(uf, mf, sf, flag, errout) + const char *uf; + const char *mf; + const char *sf; + int flag; + char *errout; +{ + register kvm_t *kd; + + if ((kd = malloc(sizeof(*kd))) == NULL) { + (void)strcpy(errout, strerror(errno)); + return (0); + } + kd->program = 0; + return (_kvm_open(kd, uf, mf, sf, flag, errout)); +} + +kvm_t * +kvm_open(uf, mf, sf, flag, program) + const char *uf; + const char *mf; + const char *sf; + int flag; + const char *program; +{ + register kvm_t *kd; + + if ((kd = malloc(sizeof(*kd))) == NULL && program != NULL) { + (void)fprintf(stderr, "%s: %s\n", strerror(errno)); + return (0); + } + kd->program = program; + return (_kvm_open(kd, uf, mf, sf, flag, NULL)); +} + +int +kvm_close(kd) + kvm_t *kd; +{ + register int error = 0; + + if (kd->pmfd >= 0) + error |= close(kd->pmfd); + if (kd->vmfd >= 0) + error |= close(kd->vmfd); + if (kd->nlfd >= 0) + error |= close(kd->nlfd); + if (kd->swfd >= 0) + error |= close(kd->swfd); + if (kd->db != 0) + error |= (kd->db->close)(kd->db); + if (kd->vmst) + _kvm_freevtop(kd); + if (kd->procbase != 0) + free((void *)kd->procbase); + if (kd->swapspc != 0) + free((void *)kd->swapspc); + if (kd->argspc != 0) + free((void *)kd->argspc); + if (kd->argbuf != 0) + free((void *)kd->argbuf); + if (kd->argv != 0) + free((void *)kd->argv); + free((void *)kd); + + return (0); +} + +/* + * Set up state necessary to do queries on the kernel namelist + * data base. If the data base is out-of-data/incompatible with + * given executable, set up things so we revert to standard nlist call. + * Only called for live kernels. Return 0 on success, -1 on failure. + */ +static int +kvm_dbopen(kd, uf) + kvm_t *kd; + const char *uf; +{ + char *cp; + DBT rec; + int dbversionlen; + struct nlist nitem; + char dbversion[_POSIX2_LINE_MAX]; + char kversion[_POSIX2_LINE_MAX]; + char dbname[MAXPATHLEN]; + + if ((cp = rindex(uf, '/')) != 0) + uf = cp + 1; + + (void)snprintf(dbname, sizeof(dbname), "%skvm_%s.db", _PATH_VARDB, uf); + kd->db = dbopen(dbname, O_RDONLY, 0, DB_HASH, NULL); + if (kd->db == 0) + return (-1); + /* + * read version out of database + */ + rec.data = VRS_KEY; + rec.size = sizeof(VRS_KEY) - 1; + if ((kd->db->get)(kd->db, (DBT *)&rec, (DBT *)&rec, 0)) + goto close; + if (rec.data == 0 || rec.size > sizeof(dbversion)) + goto close; + + bcopy(rec.data, dbversion, rec.size); + dbversionlen = rec.size; + /* + * Read version string from kernel memory. + * Since we are dealing with a live kernel, we can call kvm_read() + * at this point. + */ + rec.data = VRS_SYM; + rec.size = sizeof(VRS_SYM) - 1; + if ((kd->db->get)(kd->db, (DBT *)&rec, (DBT *)&rec, 0)) + goto close; + if (rec.data == 0 || rec.size != sizeof(struct nlist)) + goto close; + bcopy((char *)rec.data, (char *)&nitem, sizeof(nitem)); + if (kvm_read(kd, (u_long)nitem.n_value, kversion, dbversionlen) != + dbversionlen) + goto close; + /* + * If they match, we win - otherwise clear out kd->db so + * we revert to slow nlist(). + */ + if (bcmp(dbversion, kversion, dbversionlen) == 0) + return (0); +close: + (void)(kd->db->close)(kd->db); + kd->db = 0; + + return (-1); +} + +int +kvm_nlist(kd, nl) + kvm_t *kd; + struct nlist *nl; +{ + register struct nlist *p; + register int nvalid; + + /* + * If we can't use the data base, revert to the + * slow library call. + */ + if (kd->db == 0) + return (__fdnlist(kd->nlfd, nl)); + + /* + * We can use the kvm data base. Go through each nlist entry + * and look it up with a db query. + */ + nvalid = 0; + for (p = nl; p->n_name && p->n_name[0]; ++p) { + register int len; + DBT rec; + + if ((len = strlen(p->n_name)) > 4096) { + /* sanity */ + _kvm_err(kd, kd->program, "symbol too large"); + return (-1); + } + rec.data = p->n_name; + rec.size = len; + if ((kd->db->get)(kd->db, (DBT *)&rec, (DBT *)&rec, 0)) + continue; + if (rec.data == 0 || rec.size != sizeof(struct nlist)) + continue; + ++nvalid; + /* + * Avoid alignment issues. + */ + bcopy((char *)&((struct nlist *)rec.data)->n_type, + (char *)&p->n_type, + sizeof(p->n_type)); + bcopy((char *)&((struct nlist *)rec.data)->n_value, + (char *)&p->n_value, + sizeof(p->n_value)); + } + /* + * Return the number of entries that weren't found. + */ + return ((p - nl) - nvalid); +} + +ssize_t +kvm_read(kd, kva, buf, len) + kvm_t *kd; + register u_long kva; + register void *buf; + register size_t len; +{ + register int cc; + register void *cp; + + if (ISALIVE(kd)) { + /* + * We're using /dev/kmem. Just read straight from the + * device and let the active kernel do the address translation. + */ + errno = 0; + if (lseek(kd->vmfd, (off_t)kva, 0) == -1 && errno != 0) { + _kvm_err(kd, 0, "invalid address (%x)", kva); + return (0); + } + cc = read(kd->vmfd, buf, len); + if (cc < 0) { + _kvm_syserr(kd, 0, "kvm_read"); + return (0); + } else if (cc < len) + _kvm_err(kd, kd->program, "short read"); + return (cc); + } else { + cp = buf; + while (len > 0) { + u_long pa; + + cc = _kvm_kvatop(kd, kva, &pa); + if (cc == 0) + return (0); + if (cc > len) + cc = len; + errno = 0; + if (lseek(kd->pmfd, (off_t)pa, 0) == -1 && errno != 0) { + _kvm_syserr(kd, 0, _PATH_MEM); + break; + } + cc = read(kd->pmfd, cp, cc); + if (cc < 0) { + _kvm_syserr(kd, kd->program, "kvm_read"); + break; + } + /* + * If kvm_kvatop returns a bogus value or our core + * file is truncated, we might wind up seeking beyond + * the end of the core file in which case the read will + * return 0 (EOF). + */ + if (cc == 0) + break; + cp = (char *)cp + cc; + kva += cc; + len -= cc; + } + return ((char *)cp - (char *)buf); + } + /* NOTREACHED */ +} + +ssize_t +kvm_write(kd, kva, buf, len) + kvm_t *kd; + register u_long kva; + register const void *buf; + register size_t len; +{ + register int cc; + + if (ISALIVE(kd)) { + /* + * Just like kvm_read, only we write. + */ + errno = 0; + if (lseek(kd->vmfd, (off_t)kva, 0) == -1 && errno != 0) { + _kvm_err(kd, 0, "invalid address (%x)", kva); + return (0); + } + cc = write(kd->vmfd, buf, len); + if (cc < 0) { + _kvm_syserr(kd, 0, "kvm_write"); + return (0); + } else if (cc < len) + _kvm_err(kd, kd->program, "short write"); + return (cc); + } else { + _kvm_err(kd, kd->program, + "kvm_write not implemented for dead kernels"); + return (0); + } + /* NOTREACHED */ +} |