4 files changed, 412 insertions, 9 deletions

diff --git a/lib/libkvm/Makefile b/lib/libkvm/Makefile
index 52a22caf8f47c..47dc613ab7ed1 100644
--- a/lib/libkvm/Makefile
+++ b/lib/libkvm/Makefile
@@ -10,7 +10,7 @@ CFLAGS+=-DSUN4V
 .endif
 
 SRCS=	kvm.c kvm_${MACHINE_ARCH}.c kvm_cptime.c kvm_file.c kvm_getloadavg.c \
-	kvm_getswapinfo.c kvm_pcpu.c kvm_proc.c
+	kvm_getswapinfo.c kvm_pcpu.c kvm_proc.c kvm_vnet.c
 .if ${MACHINE_ARCH} == "amd64" || ${MACHINE_ARCH} == "i386" || ${MACHINE_ARCH} == "arm"
 SRCS+=	kvm_minidump_${MACHINE_ARCH}.c
 .endif
diff --git a/lib/libkvm/kvm.c b/lib/libkvm/kvm.c
index 8ff8a2b9f9864..50f752aa659db 100644
--- a/lib/libkvm/kvm.c
+++ b/lib/libkvm/kvm.c
@@ -41,6 +41,9 @@ static char sccsid[] = "@(#)kvm.c	8.2 (Berkeley) 2/13/94";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
+
+#define	_WANT_VNET
+
 #include <sys/user.h>
 #include <sys/proc.h>
 #include <sys/ioctl.h>
@@ -48,6 +51,8 @@ static char sccsid[] = "@(#)kvm.c	8.2 (Berkeley) 2/13/94";
 #include <sys/sysctl.h>
 #include <sys/linker.h>
 
+#include <net/vnet.h>
+
 #include <vm/vm.h>
 #include <vm/vm_param.h>
 
@@ -62,6 +67,7 @@ static char sccsid[] = "@(#)kvm.c	8.2 (Berkeley) 2/13/94";
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <unistd.h>
 
 #include "kvm_private.h"
@@ -299,34 +305,154 @@ kvm_close(kd)
 	return (0);
 }
 
+/*
+ * Walk the list of unresolved symbols, generate a new list and prefix the
+ * symbol names, try again, and merge back what we could resolve.
+ */
+static int
+kvm_fdnlist_prefix(kvm_t *kd, struct nlist *nl, int missing, const char *prefix,
+    uintptr_t (*validate_fn)(kvm_t *, uintptr_t))
+{
+	struct nlist *n, *np, *p;
+	char *cp, *ce;
+	size_t len;
+	int unresolved;
+
+	/*
+	 * Calculate the space we need to malloc for nlist and names.
+	 * We are going to store the name twice for later lookups: once
+	 * with the prefix and once the unmodified name delmited by \0.
+	 */
+	len = 0;
+	unresolved = 0;
+	for (p = nl; p->n_name && p->n_name[0]; ++p) {
+		if (p->n_type != N_UNDF)
+			continue;
+		len += sizeof(struct nlist) + strlen(prefix) +
+		    2 * (strlen(p->n_name) + 1);
+		unresolved++;
+	}
+	if (unresolved == 0)
+		return (unresolved);
+	/* Add space for the terminating nlist entry. */
+	len += sizeof(struct nlist);
+	unresolved++;
+
+	/* Alloc one chunk for (nlist, [names]) and setup pointers. */
+	n = np = malloc(len);
+	bzero(n, len);
+	if (n == NULL)
+		return (missing);
+	cp = ce = (char *)np;
+	cp += unresolved * sizeof(struct nlist);
+	ce += len;
+
+	/* Generate shortened nlist with special prefix. */
+	unresolved = 0;
+	for (p = nl; p->n_name && p->n_name[0]; ++p) {
+		if (p->n_type != N_UNDF)
+			continue;
+		bcopy(p, np, sizeof(struct nlist));
+		/* Save the new\0orig. name so we can later match it again. */
+		len = snprintf(cp, ce - cp, "%s%s%c%s", prefix,
+		    (prefix[0] != '\0' && p->n_name[0] == '_') ?
+			(p->n_name + 1) : p->n_name, '\0', p->n_name);
+		if (len >= ce - cp)
+			continue;
+		np->n_name = cp;
+		cp += len + 1;
+		np++;
+		unresolved++;
+	}
+
+	/* Do lookup on the reduced list. */
+	np = n;
+	unresolved = __fdnlist(kd->nlfd, np);
+
+	/* Check if we could resolve further symbols and update the list. */
+	if (unresolved >= 0 && unresolved < missing) {
+		/* Find the first freshly resolved entry. */
+		for (; np->n_name && np->n_name[0]; np++)
+			if (np->n_type != N_UNDF)
+				break;
+		/*
+		 * The lists are both in the same order,
+		 * so we can walk them in parallel.
+		 */
+		for (p = nl; np->n_name && np->n_name[0] &&
+		    p->n_name && p->n_name[0]; ++p) {
+			if (p->n_type != N_UNDF)
+				continue;
+			/* Skip expanded name and compare to orig. one. */
+			cp = np->n_name + strlen(np->n_name) + 1;
+			if (strcmp(cp, p->n_name))
+				continue;
+			/* Update nlist with new, translated results. */
+			p->n_type = np->n_type;
+			p->n_other = np->n_other;
+			p->n_desc = np->n_desc;
+			if (validate_fn)
+				p->n_value = (*validate_fn)(kd, np->n_value);
+			else
+				p->n_value = np->n_value;
+			missing--;
+			/* Find next freshly resolved entry. */
+			for (np++; np->n_name && np->n_name[0]; np++)
+				if (np->n_type != N_UNDF)
+					break;
+		}
+	}
+	/* We could assert missing = unresolved here. */
+
+	free(n);
+	return (unresolved);
+}
+
 int
-kvm_nlist(kd, nl)
-	kvm_t *kd;
-	struct nlist *nl;
+_kvm_nlist(kvm_t *kd, struct nlist *nl, int initialize)
 {
 	struct nlist *p;
 	int nvalid;
 	struct kld_sym_lookup lookup;
 	int error;
-
+	char *prefix = "", symname[1024]; /* XXX-BZ symbol name length limit? */
 	/*
 	 * If we can't use the kld symbol lookup, revert to the
 	 * slow library call.
 	 */
-	if (!ISALIVE(kd))
-		return (__fdnlist(kd->nlfd, nl));
+	if (!ISALIVE(kd)) {
+		error = __fdnlist(kd->nlfd, nl);
+		if (error <= 0)			/* Hard error or success. */
+			return (error);
+
+		if (_kvm_vnet_initialized(kd, initialize))
+			error = kvm_fdnlist_prefix(kd, nl, error,
+			    VNET_SYMPREFIX, _kvm_vnet_validaddr);
+
+		return (error);
+	}
 
 	/*
 	 * We can use the kld lookup syscall.  Go through each nlist entry
 	 * and look it up with a kldsym(2) syscall.
 	 */
 	nvalid = 0;
+again:
 	for (p = nl; p->n_name && p->n_name[0]; ++p) {
+		if (p->n_type != N_UNDF)
+			continue;
+
 		lookup.version = sizeof(lookup);
-		lookup.symname = p->n_name;
 		lookup.symvalue = 0;
 		lookup.symsize = 0;
 
+		error = snprintf(symname, sizeof(symname), "%s%s", prefix,
+		    (prefix[0] != '\0' && p->n_name[0] == '_') ?
+			(p->n_name + 1) : p->n_name);
+		if (error >= sizeof(symname))
+			continue;
+
+		lookup.symname = symname;
 		if (lookup.symname[0] == '_')
 			lookup.symname++;
 
@@ -334,11 +460,28 @@ kvm_nlist(kd, nl)
 			p->n_type = N_TEXT;
 			p->n_other = 0;
 			p->n_desc = 0;
-			p->n_value = lookup.symvalue;
+			if (_kvm_vnet_initialized(kd, initialize) &&
+			    !strcmp(prefix, VNET_SYMPREFIX))
+				p->n_value =
+				    _kvm_vnet_validaddr(kd, lookup.symvalue);
+			else
+				p->n_value = lookup.symvalue;
 			++nvalid;
 			/* lookup.symsize */
 		}
 	}
+
+	/*
+	 * Check the number of entries that weren't found. If they exist,
+	 * try again with a prefix for virtualized symbol names.
+	 */
+	error = ((p - nl) - nvalid);
+	if (error && _kvm_vnet_initialized(kd, initialize) &&
+	    strcmp(prefix, VNET_SYMPREFIX)) {
+		prefix = VNET_SYMPREFIX;
+		goto again;
+	}
+
 	/*
 	 * Return the number of entries that weren't found. If they exist,
 	 * also fill internal error buffer.
@@ -349,6 +492,19 @@ kvm_nlist(kd, nl)
 	return (error);
 }
 
+int
+kvm_nlist(kd, nl)
+	kvm_t *kd;
+	struct nlist *nl;
+{
+
+	/*
+	 * If called via the public interface, permit intialization of
+	 * further virtualized modules on demand.
+	 */
+	return (_kvm_nlist(kd, nl, 1));
+}
+
 ssize_t
 kvm_read(kd, kva, buf, len)
 	kvm_t *kd;
diff --git a/lib/libkvm/kvm_private.h b/lib/libkvm/kvm_private.h
index 88ff7166b59b3..cc073db5fe424 100644
--- a/lib/libkvm/kvm_private.h
+++ b/lib/libkvm/kvm_private.h
@@ -62,6 +62,12 @@ struct __kvm {
 	 */
 	struct vmstate *vmst;
 	int	rawdump;	/* raw dump format */
+
+	int		vnet_initialized;	/* vnet fields set up */
+	uintptr_t	vnet_start;	/* start of kernel's vnet region */
+	uintptr_t	vnet_stop;	/* stop of kernel's vnet region */
+	uintptr_t	vnet_current;	/* vnet we're working with */
+	uintptr_t	vnet_base;	/* vnet base of current vnet */
 };
 
 /*
@@ -74,10 +80,14 @@ void	 _kvm_freevtop(kvm_t *);
 int	 _kvm_initvtop(kvm_t *);
 int	 _kvm_kvatop(kvm_t *, u_long, off_t *);
 void	*_kvm_malloc(kvm_t *kd, size_t);
+int	 _kvm_nlist(kvm_t *, struct nlist *, int);
 void	*_kvm_realloc(kvm_t *kd, void *, size_t);
 void	 _kvm_syserr (kvm_t *kd, const char *program, const char *fmt, ...)
 	    __printflike(3, 4);
 int	 _kvm_uvatop(kvm_t *, const struct proc *, u_long, u_long *);
+int	 _kvm_vnet_selectpid(kvm_t *, pid_t);
+int	 _kvm_vnet_initialized(kvm_t *, int);
+uintptr_t _kvm_vnet_validaddr(kvm_t *, uintptr_t);
 
 #if defined(__amd64__) || defined(__i386__) || defined(__arm__)
 void	 _kvm_minidump_freevtop(kvm_t *);
diff --git a/lib/libkvm/kvm_vnet.c b/lib/libkvm/kvm_vnet.c
new file mode 100644
index 0000000000000..13f7cf4c664fe
--- /dev/null
+++ b/lib/libkvm/kvm_vnet.c
@@ -0,0 +1,237 @@
+/*-
+ * Copyright (c) 2009 Robert N. M. Watson
+ * Copyright (c) 2009 Bjoern A. Zeeb <bz@FreeBSD.org>
+ * All rights reserved.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+
+#define	_WANT_PRISON
+#define	_WANT_UCRED
+#define	_WANT_VNET
+
+#include <sys/_lock.h>
+#include <sys/_mutex.h>
+#include <sys/_task.h>
+#include <sys/jail.h>
+#include <sys/proc.h>
+#include <sys/types.h>
+#include <sys/vimage.h>
+
+#include <net/vnet.h>
+
+#include <nlist.h>
+#include <kvm.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "kvm_private.h"
+
+/*
+ * Set up libkvm to handle virtual network stack symbols by selecting a
+ * starting pid.
+ */
+int
+_kvm_vnet_selectpid(kvm_t *kd, pid_t pid)
+{
+	struct proc proc;
+	struct thread td;
+	struct ucred cred;
+	struct prison prison;
+	struct vnet vnet;
+	struct nlist nl[] = {
+		/*
+		 * Note: kvm_nlist strips the first '_' so add an extra one
+		 * here to __{start,stop}_set_vnet.
+		 */
+#define	NLIST_START_VNET	0
+		{ .n_name = "___start_" VNET_SETNAME },
+#define	NLIST_STOP_VNET		1
+		{ .n_name = "___stop_" VNET_SETNAME },
+#define	NLIST_VNET_HEAD		2
+		{ .n_name = "vnet_head" },
+#define	NLIST_ALLPROC		3
+		{ .n_name = "allproc" },
+#define	NLIST_DUMPTID		4
+		{ .n_name = "dumptid" },
+#define	NLIST_PROC0		5
+		{ .n_name = "proc0" },
+		{ .n_name = NULL },
+	};
+	uintptr_t procp, tdp, credp;
+	lwpid_t dumptid;
+
+	/*
+	 * Locate and cache locations of important symbols
+	 * using the internal version of _kvm_nlist, turning
+	 * off initialization to avoid recursion in case of
+	 * unresolveable symbols.
+	 */
+	if (_kvm_nlist(kd, nl, 0) != 0) {
+		/*
+		 * XXX-BZ: ___start_/___stop_VNET_SETNAME may fail.
+		 * For now do not report an error here as we are called
+		 * internally and in `void context' until we merge the
+		 * functionality to optionally activate this into programs.
+		 * By that time we can properly fail and let the callers
+		 * handle the error.
+		 */
+		/* _kvm_err(kd, kd->program, "%s: no namelist", __func__); */
+		return (-1);
+	}
+
+	/*
+	 * Auto-detect if this is a crashdump by reading dumptid.
+	 */
+	dumptid = 0;
+	if (nl[NLIST_DUMPTID].n_value) {
+		if (kvm_read(kd, nl[NLIST_DUMPTID].n_value, &dumptid,
+		    sizeof(dumptid)) != sizeof(dumptid)) {
+			_kvm_err(kd, kd->program, "%s: dumptid", __func__);
+			return (-1);
+		}
+	}
+
+	/*
+	 * First, find the process for this pid.  If we are workig on a dump,
+	 * either locate the thread dumptid is refering to or proc0.
+	 * Based on either, take the address of the ucred.
+	 */
+	credp = 0;
+
+	procp = nl[NLIST_ALLPROC].n_value;
+#define	VMCORE_VNET_OF_PROC0
+#ifdef VMCORE_VNET_OF_PROC0
+	if (dumptid > 0) {
+		procp = nl[NLIST_PROC0].n_value;
+		pid = 0;
+	}
+#endif
+	while (procp != 0) {
+		if (kvm_read(kd, procp, &proc, sizeof(proc)) != sizeof(proc)) {
+			_kvm_err(kd, kd->program, "%s: proc", __func__);
+			return (-1);
+		}
+#ifndef VMCORE_VNET_OF_PROC0
+		if (dumptid > 0) {
+			tdp = (uintptr_t)TAILQ_FIRST(&proc.p_threads);
+			while (tdp != 0) {
+				if (kvm_read(kd, tdp, &td, sizeof(td)) !=
+				    sizeof(td)) {
+					_kvm_err(kd, kd->program, "%s: thread",
+					    __func__);
+					return (-1);
+				}
+				if (td.td_tid == dumptid) {
+					credp = (uintptr_t)td.td_ucred;
+					break;
+				}
+				tdp = (uintptr_t)TAILQ_NEXT(&td, td_plist);
+			}
+		} else
+#endif
+		if (proc.p_pid == pid)
+			credp = (uintptr_t)proc.p_ucred;
+		if (credp != 0)
+			break;
+		procp = (uintptr_t)LIST_NEXT(&proc, p_list);
+	}
+	if (credp == 0) {
+		_kvm_err(kd, kd->program, "%s: pid/tid not found", __func__);
+		return (-1);
+	}
+	if (kvm_read(kd, (uintptr_t)credp, &cred, sizeof(cred)) !=
+	    sizeof(cred)) {
+		_kvm_err(kd, kd->program, "%s: cred", __func__);
+		return (-1);
+	}
+	if (cred.cr_prison == NULL) {
+		_kvm_err(kd, kd->program, "%s: no jail", __func__);
+		return (-1);
+	}
+	if (kvm_read(kd, (uintptr_t)cred.cr_prison, &prison, sizeof(prison)) !=
+	    sizeof(prison)) {
+		_kvm_err(kd, kd->program, "%s: prison", __func__);
+		return (-1);
+	}
+	if (prison.pr_vnet == NULL) {
+		_kvm_err(kd, kd->program, "%s: no vnet", __func__);
+		return (-1);
+	}
+	if (kvm_read(kd, (uintptr_t)prison.pr_vnet, &vnet, sizeof(vnet)) !=
+	    sizeof(vnet)) {
+		_kvm_err(kd, kd->program, "%s: vnet", __func__);
+		return (-1);
+	}
+	if (vnet.vnet_magic_n != VNET_MAGIC_N) {
+		_kvm_err(kd, kd->program, "%s: invalid vnet magic#", __func__);
+		return (-1);
+	}
+	kd->vnet_initialized = 1;
+	kd->vnet_start = nl[NLIST_START_VNET].n_value;
+	kd->vnet_stop = nl[NLIST_STOP_VNET].n_value;
+	kd->vnet_current = (uintptr_t)prison.pr_vnet;
+	kd->vnet_base = (uintptr_t)vnet.vnet_data_mem - kd->vnet_start;
+	return (0);
+}
+
+/*
+ * Check whether the vnet module has been initialized sucessfully
+ * or not, intialize it if permitted.
+ */
+int
+_kvm_vnet_initialized(kvm_t *kd, int intialize)
+{
+
+	if (kd->vnet_initialized || !intialize)
+		return (kd->vnet_initialized);
+
+	(void) _kvm_vnet_selectpid(kd, getpid());
+
+	return (kd->vnet_initialized);
+}
+
+/*
+ * Check whether the value is within the vnet symbol range and
+ * only if so adjust the offset relative to the current base.
+ */
+uintptr_t
+_kvm_vnet_validaddr(kvm_t *kd, uintptr_t value)
+{
+
+	if (value == 0)
+		return (value);
+
+	if (!kd->vnet_initialized)
+		return (value);
+
+	if (value < kd->vnet_start || value >= kd->vnet_stop)
+		return (value);
+
+	return (kd->vnet_base + value);
+}