1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2008, Juniper Networks, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the author nor the names of any co-contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 #include <sys/param.h> 33 #include <sys/endian.h> 34 #include <sys/kerneldump.h> 35 #include <sys/mman.h> 36 37 #include <elf.h> 38 #include <kvm.h> 39 #include <limits.h> 40 #include <stdlib.h> 41 #include <string.h> 42 43 #include "kvm_private.h" 44 45 struct vmstate { 46 void *map; 47 size_t mapsz; 48 size_t dmphdrsz; 49 Elf64_Ehdr *eh; 50 Elf64_Phdr *ph; 51 }; 52 53 static int 54 valid_elf_header(kvm_t *kd, Elf64_Ehdr *eh) 55 { 56 57 if (!IS_ELF(*eh)) 58 return (0); 59 if (eh->e_ident[EI_CLASS] != ELFCLASS64) 60 return (0); 61 if (eh->e_ident[EI_DATA] != ELFDATA2MSB && 62 eh->e_ident[EI_DATA] != ELFDATA2LSB) 63 return (0); 64 if (eh->e_ident[EI_VERSION] != EV_CURRENT) 65 return (0); 66 if (eh->e_ident[EI_OSABI] != ELFOSABI_STANDALONE) 67 return (0); 68 if (_kvm16toh(kd, eh->e_type) != ET_CORE) 69 return (0); 70 if (_kvm16toh(kd, eh->e_machine) != EM_PPC64) 71 return (0); 72 /* Can't think of anything else to check... */ 73 return (1); 74 } 75 76 static size_t 77 dump_header_size(struct kerneldumpheader *dh) 78 { 79 80 if (strcmp(dh->magic, KERNELDUMPMAGIC) != 0) 81 return (0); 82 if (strcmp(dh->architecture, "powerpc64") != 0 && 83 strcmp(dh->architecture, "powerpc64le") != 0) 84 return (0); 85 /* That should do it... */ 86 return (sizeof(*dh)); 87 } 88 89 /* 90 * Map the ELF headers into the process' address space. We do this in two 91 * steps: first the ELF header itself and using that information the whole 92 * set of headers. 93 */ 94 static int 95 powerpc_maphdrs(kvm_t *kd) 96 { 97 struct vmstate *vm; 98 size_t mapsz; 99 100 vm = kd->vmst; 101 102 vm->mapsz = sizeof(*vm->eh) + sizeof(struct kerneldumpheader); 103 vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 104 if (vm->map == MAP_FAILED) { 105 _kvm_err(kd, kd->program, "cannot map corefile"); 106 return (-1); 107 } 108 vm->dmphdrsz = 0; 109 vm->eh = vm->map; 110 if (!valid_elf_header(kd, vm->eh)) { 111 /* 112 * Hmmm, no ELF header. Maybe we still have a dump header. 113 * This is normal when the core file wasn't created by 114 * savecore(8), but instead was dumped over TFTP. We can 115 * easily skip the dump header... 116 */ 117 vm->dmphdrsz = dump_header_size(vm->map); 118 if (vm->dmphdrsz == 0) 119 goto inval; 120 vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz); 121 if (!valid_elf_header(kd, vm->eh)) 122 goto inval; 123 } 124 mapsz = _kvm16toh(kd, vm->eh->e_phentsize) * 125 _kvm16toh(kd, vm->eh->e_phnum) + _kvm64toh(kd, vm->eh->e_phoff); 126 munmap(vm->map, vm->mapsz); 127 128 /* Map all headers. */ 129 vm->mapsz = vm->dmphdrsz + mapsz; 130 vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 131 if (vm->map == MAP_FAILED) { 132 _kvm_err(kd, kd->program, "cannot map corefile headers"); 133 return (-1); 134 } 135 vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz); 136 vm->ph = (void *)((uintptr_t)vm->eh + 137 (uintptr_t)_kvm64toh(kd, vm->eh->e_phoff)); 138 return (0); 139 140 inval: 141 _kvm_err(kd, kd->program, "invalid corefile"); 142 return (-1); 143 } 144 145 /* 146 * Determine the offset within the corefile corresponding the virtual 147 * address. Return the number of contiguous bytes in the corefile or 148 * 0 when the virtual address is invalid. 149 */ 150 static size_t 151 powerpc64_va2off(kvm_t *kd, kvaddr_t va, off_t *ofs) 152 { 153 struct vmstate *vm = kd->vmst; 154 Elf64_Phdr *ph; 155 int nph; 156 157 ph = vm->ph; 158 nph = _kvm16toh(kd, vm->eh->e_phnum); 159 while (nph && (va < _kvm64toh(kd, ph->p_vaddr) || 160 va >= _kvm64toh(kd, ph->p_vaddr) + _kvm64toh(kd, ph->p_memsz))) { 161 nph--; 162 ph = (void *)((uintptr_t)ph + 163 _kvm16toh(kd, vm->eh->e_phentsize)); 164 } 165 if (nph == 0) 166 return (0); 167 168 /* Segment found. Return file offset and range. */ 169 *ofs = vm->dmphdrsz + _kvm64toh(kd, ph->p_offset) + 170 (va - _kvm64toh(kd, ph->p_vaddr)); 171 return (_kvm64toh(kd, ph->p_memsz) - 172 (va - _kvm64toh(kd, ph->p_vaddr))); 173 } 174 175 static void 176 _powerpc64_freevtop(kvm_t *kd) 177 { 178 struct vmstate *vm = kd->vmst; 179 180 if (vm->eh != MAP_FAILED) 181 munmap(vm->eh, vm->mapsz); 182 free(vm); 183 kd->vmst = NULL; 184 } 185 186 static int 187 _powerpc64_probe(kvm_t *kd) 188 { 189 190 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_PPC64) && 191 kd->nlehdr.e_ident[EI_DATA] == ELFDATA2MSB); 192 } 193 194 static int 195 _powerpc64le_probe(kvm_t *kd) 196 { 197 198 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_PPC64) && 199 kd->nlehdr.e_ident[EI_DATA] == ELFDATA2LSB); 200 } 201 202 static int 203 _powerpc64_initvtop(kvm_t *kd) 204 { 205 206 kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst)); 207 if (kd->vmst == NULL) 208 return (-1); 209 210 if (powerpc_maphdrs(kd) == -1) 211 return (-1); 212 213 return (0); 214 } 215 216 static int 217 _powerpc64_kvatop(kvm_t *kd, kvaddr_t va, off_t *ofs) 218 { 219 struct vmstate *vm; 220 221 vm = kd->vmst; 222 if (_kvm64toh(kd, vm->ph->p_paddr) == 0xffffffffffffffff) 223 return ((int)powerpc64_va2off(kd, va, ofs)); 224 225 _kvm_err(kd, kd->program, "Raw corefile not supported"); 226 return (0); 227 } 228 229 static int 230 _powerpc64_native(kvm_t *kd __unused) 231 { 232 233 #if defined(__powerpc64__) && BYTE_ORDER == BIG_ENDIAN 234 return (1); 235 #else 236 return (0); 237 #endif 238 } 239 240 static int 241 _powerpc64le_native(kvm_t *kd __unused) 242 { 243 244 #if defined(__powerpc64__) && BYTE_ORDER == LITTLE_ENDIAN 245 return (1); 246 #else 247 return (0); 248 #endif 249 } 250 251 static struct kvm_arch kvm_powerpc64 = { 252 .ka_probe = _powerpc64_probe, 253 .ka_initvtop = _powerpc64_initvtop, 254 .ka_freevtop = _powerpc64_freevtop, 255 .ka_kvatop = _powerpc64_kvatop, 256 .ka_native = _powerpc64_native, 257 }; 258 259 static struct kvm_arch kvm_powerpc64le = { 260 .ka_probe = _powerpc64le_probe, 261 .ka_initvtop = _powerpc64_initvtop, 262 .ka_freevtop = _powerpc64_freevtop, 263 .ka_kvatop = _powerpc64_kvatop, 264 .ka_native = _powerpc64le_native, 265 }; 266 267 KVM_ARCH(kvm_powerpc64); 268 KVM_ARCH(kvm_powerpc64le); 269