2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2009 Robert N. M. Watson
5 * Copyright (c) 2009 Bjoern A. Zeeb <bz@FreeBSD.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
33 #include <sys/param.h>
39 #include <sys/_lock.h>
40 #include <sys/_mutex.h>
41 #include <sys/_task.h>
44 #include <sys/types.h>
54 #include "kvm_private.h"
57 * Set up libkvm to handle virtual network stack symbols by selecting a
61 _kvm_vnet_selectpid(kvm_t *kd, pid_t pid)
67 struct kvm_nlist nl[] = {
69 * Note: kvm_nlist strips the first '_' so add an extra one
70 * here to __{start,stop}_set_vnet.
72 #define NLIST_START_VNET 0
73 { .n_name = "___start_" VNET_SETNAME },
74 #define NLIST_STOP_VNET 1
75 { .n_name = "___stop_" VNET_SETNAME },
76 #define NLIST_VNET_HEAD 2
77 { .n_name = "vnet_head" },
78 #define NLIST_ALLPROC 3
79 { .n_name = "allproc" },
80 #define NLIST_DUMPTID 4
81 { .n_name = "dumptid" },
83 { .n_name = "proc0" },
86 uintptr_t procp, credp;
87 #define VMCORE_VNET_OF_PROC0
88 #ifndef VMCORE_VNET_OF_PROC0
95 * XXX: This only works for native kernels for now.
101 * Locate and cache locations of important symbols
102 * using the internal version of _kvm_nlist, turning
103 * off initialization to avoid recursion in case of
104 * unresolveable symbols.
106 if (_kvm_nlist(kd, nl, 0) != 0) {
108 * XXX-BZ: ___start_/___stop_VNET_SETNAME may fail.
109 * For now do not report an error here as we are called
110 * internally and in `void context' until we merge the
111 * functionality to optionally activate this into programs.
112 * By that time we can properly fail and let the callers
115 /* _kvm_err(kd, kd->program, "%s: no namelist", __func__); */
120 * Auto-detect if this is a crashdump by reading dumptid.
123 if (nl[NLIST_DUMPTID].n_value) {
124 if (kvm_read(kd, nl[NLIST_DUMPTID].n_value, &dumptid,
125 sizeof(dumptid)) != sizeof(dumptid)) {
126 _kvm_err(kd, kd->program, "%s: dumptid", __func__);
132 * First, find the process for this pid. If we are working on a
133 * dump, either locate the thread dumptid is referring to or proc0.
134 * Based on either, take the address of the ucred.
138 procp = nl[NLIST_ALLPROC].n_value;
139 #ifdef VMCORE_VNET_OF_PROC0
141 procp = nl[NLIST_PROC0].n_value;
146 if (kvm_read(kd, procp, &proc, sizeof(proc)) != sizeof(proc)) {
147 _kvm_err(kd, kd->program, "%s: proc", __func__);
150 #ifndef VMCORE_VNET_OF_PROC0
152 tdp = (uintptr_t)TAILQ_FIRST(&proc.p_threads);
154 if (kvm_read(kd, tdp, &td, sizeof(td)) !=
156 _kvm_err(kd, kd->program, "%s: thread",
160 if (td.td_tid == dumptid) {
161 credp = (uintptr_t)td.td_ucred;
164 tdp = (uintptr_t)TAILQ_NEXT(&td, td_plist);
168 if (proc.p_pid == pid)
169 credp = (uintptr_t)proc.p_ucred;
172 procp = (uintptr_t)LIST_NEXT(&proc, p_list);
175 _kvm_err(kd, kd->program, "%s: pid/tid not found", __func__);
178 if (kvm_read(kd, (uintptr_t)credp, &cred, sizeof(cred)) !=
180 _kvm_err(kd, kd->program, "%s: cred", __func__);
183 if (cred.cr_prison == NULL) {
184 _kvm_err(kd, kd->program, "%s: no jail", __func__);
187 if (kvm_read(kd, (uintptr_t)cred.cr_prison, &prison, sizeof(prison)) !=
189 _kvm_err(kd, kd->program, "%s: prison", __func__);
192 if (prison.pr_vnet == NULL) {
193 _kvm_err(kd, kd->program, "%s: no vnet", __func__);
196 if (kvm_read(kd, (uintptr_t)prison.pr_vnet, &vnet, sizeof(vnet)) !=
198 _kvm_err(kd, kd->program, "%s: vnet", __func__);
201 if (vnet.vnet_magic_n != VNET_MAGIC_N) {
202 _kvm_err(kd, kd->program, "%s: invalid vnet magic#", __func__);
205 kd->vnet_initialized = 1;
206 kd->vnet_start = nl[NLIST_START_VNET].n_value;
207 kd->vnet_stop = nl[NLIST_STOP_VNET].n_value;
208 kd->vnet_current = (uintptr_t)prison.pr_vnet;
209 kd->vnet_base = vnet.vnet_data_base;
214 * Check whether the vnet module has been initialized successfully
215 * or not, initialize it if permitted.
218 _kvm_vnet_initialized(kvm_t *kd, int intialize)
221 if (kd->vnet_initialized || !intialize)
222 return (kd->vnet_initialized);
224 (void) _kvm_vnet_selectpid(kd, getpid());
226 return (kd->vnet_initialized);
230 * Check whether the value is within the vnet symbol range and
231 * only if so adjust the offset relative to the current base.
234 _kvm_vnet_validaddr(kvm_t *kd, kvaddr_t value)
240 if (!kd->vnet_initialized)
243 if (value < kd->vnet_start || value >= kd->vnet_stop)
246 return (kd->vnet_base + value);