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Diffstat (limited to 'lib/libkvm/kvm.c')
-rw-r--r--lib/libkvm/kvm.c540
1 files changed, 540 insertions, 0 deletions
diff --git a/lib/libkvm/kvm.c b/lib/libkvm/kvm.c
new file mode 100644
index 000000000000..a76f61e8d52c
--- /dev/null
+++ b/lib/libkvm/kvm.c
@@ -0,0 +1,540 @@
+/*-
+ * 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 *));
+
+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->vmfd = -1;
+ kd->pmfd = -1;
+ kd->swfd = -1;
+ kd->nlfd = -1;
+ kd->vmst = 0;
+ kd->db = 0;
+ kd->procbase = 0;
+ kd->argspc = 0;
+ kd->argv = 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->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;
+ (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 */
+}
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