/*- * Copyright (c) 2009 Robert N. M. Watson * Copyright (c) 2009 Bjoern A. Zeeb * 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 __FBSDID("$FreeBSD$"); #include #define _WANT_PRISON #define _WANT_UCRED #define _WANT_VNET #include #include #include #include #include #include #include #include #include #include #include #include #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 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, credp; #define VMCORE_VNET_OF_PROC0 #ifndef VMCORE_VNET_OF_PROC0 struct thread td; uintptr_t tdp; #endif 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 working 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; #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 = vnet.vnet_data_base; 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); }