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/param.h> 32 #include <sys/endian.h> 33 #include <sys/kerneldump.h> 34 #include <sys/mman.h> 35 36 #include <elf.h> 37 #include <kvm.h> 38 #include <limits.h> 39 #include <stdlib.h> 40 #include <string.h> 41 42 #include "kvm_private.h" 43 44 struct vmstate { 45 void *map; 46 size_t mapsz; 47 size_t dmphdrsz; 48 Elf64_Ehdr *eh; 49 Elf64_Phdr *ph; 50 }; 51 52 static int 53 valid_elf_header(kvm_t *kd, Elf64_Ehdr *eh) 54 { 55 56 if (!IS_ELF(*eh)) 57 return (0); 58 if (eh->e_ident[EI_CLASS] != ELFCLASS64) 59 return (0); 60 if (eh->e_ident[EI_DATA] != ELFDATA2MSB && 61 eh->e_ident[EI_DATA] != ELFDATA2LSB) 62 return (0); 63 if (eh->e_ident[EI_VERSION] != EV_CURRENT) 64 return (0); 65 if (eh->e_ident[EI_OSABI] != ELFOSABI_STANDALONE) 66 return (0); 67 if (_kvm16toh(kd, eh->e_type) != ET_CORE) 68 return (0); 69 if (_kvm16toh(kd, eh->e_machine) != EM_PPC64) 70 return (0); 71 /* Can't think of anything else to check... */ 72 return (1); 73 } 74 75 static size_t 76 dump_header_size(struct kerneldumpheader *dh) 77 { 78 79 if (strcmp(dh->magic, KERNELDUMPMAGIC) != 0) 80 return (0); 81 if (strcmp(dh->architecture, "powerpc64") != 0 && 82 strcmp(dh->architecture, "powerpc64le") != 0) 83 return (0); 84 /* That should do it... */ 85 return (sizeof(*dh)); 86 } 87 88 /* 89 * Map the ELF headers into the process' address space. We do this in two 90 * steps: first the ELF header itself and using that information the whole 91 * set of headers. 92 */ 93 static int 94 powerpc_maphdrs(kvm_t *kd) 95 { 96 struct vmstate *vm; 97 size_t mapsz; 98 99 vm = kd->vmst; 100 101 vm->mapsz = sizeof(*vm->eh) + sizeof(struct kerneldumpheader); 102 vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 103 if (vm->map == MAP_FAILED) { 104 _kvm_err(kd, kd->program, "cannot map corefile"); 105 return (-1); 106 } 107 vm->dmphdrsz = 0; 108 vm->eh = vm->map; 109 if (!valid_elf_header(kd, vm->eh)) { 110 /* 111 * Hmmm, no ELF header. Maybe we still have a dump header. 112 * This is normal when the core file wasn't created by 113 * savecore(8), but instead was dumped over TFTP. We can 114 * easily skip the dump header... 115 */ 116 vm->dmphdrsz = dump_header_size(vm->map); 117 if (vm->dmphdrsz == 0) 118 goto inval; 119 vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz); 120 if (!valid_elf_header(kd, vm->eh)) 121 goto inval; 122 } 123 mapsz = _kvm16toh(kd, vm->eh->e_phentsize) * 124 _kvm16toh(kd, vm->eh->e_phnum) + _kvm64toh(kd, vm->eh->e_phoff); 125 munmap(vm->map, vm->mapsz); 126 127 /* Map all headers. */ 128 vm->mapsz = vm->dmphdrsz + mapsz; 129 vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 130 if (vm->map == MAP_FAILED) { 131 _kvm_err(kd, kd->program, "cannot map corefile headers"); 132 return (-1); 133 } 134 vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz); 135 vm->ph = (void *)((uintptr_t)vm->eh + 136 (uintptr_t)_kvm64toh(kd, vm->eh->e_phoff)); 137 return (0); 138 139 inval: 140 _kvm_err(kd, kd->program, "invalid corefile"); 141 return (-1); 142 } 143 144 /* 145 * Determine the offset within the corefile corresponding the virtual 146 * address. Return the number of contiguous bytes in the corefile or 147 * 0 when the virtual address is invalid. 148 */ 149 static size_t 150 powerpc64_va2off(kvm_t *kd, kvaddr_t va, off_t *ofs) 151 { 152 struct vmstate *vm = kd->vmst; 153 Elf64_Phdr *ph; 154 int nph; 155 156 ph = vm->ph; 157 nph = _kvm16toh(kd, vm->eh->e_phnum); 158 while (nph && (va < _kvm64toh(kd, ph->p_vaddr) || 159 va >= _kvm64toh(kd, ph->p_vaddr) + _kvm64toh(kd, ph->p_memsz))) { 160 nph--; 161 ph = (void *)((uintptr_t)ph + 162 _kvm16toh(kd, vm->eh->e_phentsize)); 163 } 164 if (nph == 0) 165 return (0); 166 167 /* Segment found. Return file offset and range. */ 168 *ofs = vm->dmphdrsz + _kvm64toh(kd, ph->p_offset) + 169 (va - _kvm64toh(kd, ph->p_vaddr)); 170 return (_kvm64toh(kd, ph->p_memsz) - 171 (va - _kvm64toh(kd, ph->p_vaddr))); 172 } 173 174 static void 175 _powerpc64_freevtop(kvm_t *kd) 176 { 177 struct vmstate *vm = kd->vmst; 178 179 if (vm->eh != MAP_FAILED) 180 munmap(vm->eh, vm->mapsz); 181 free(vm); 182 kd->vmst = NULL; 183 } 184 185 static int 186 _powerpc64_probe(kvm_t *kd) 187 { 188 189 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_PPC64) && 190 kd->nlehdr.e_ident[EI_DATA] == ELFDATA2MSB); 191 } 192 193 static int 194 _powerpc64le_probe(kvm_t *kd) 195 { 196 197 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_PPC64) && 198 kd->nlehdr.e_ident[EI_DATA] == ELFDATA2LSB); 199 } 200 201 static int 202 _powerpc64_initvtop(kvm_t *kd) 203 { 204 205 kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst)); 206 if (kd->vmst == NULL) 207 return (-1); 208 209 if (powerpc_maphdrs(kd) == -1) 210 return (-1); 211 212 return (0); 213 } 214 215 static int 216 _powerpc64_kvatop(kvm_t *kd, kvaddr_t va, off_t *ofs) 217 { 218 struct vmstate *vm; 219 220 vm = kd->vmst; 221 if (_kvm64toh(kd, vm->ph->p_paddr) == 0xffffffffffffffff) 222 return ((int)powerpc64_va2off(kd, va, ofs)); 223 224 _kvm_err(kd, kd->program, "Raw corefile not supported"); 225 return (0); 226 } 227 228 static int 229 _powerpc64_native(kvm_t *kd __unused) 230 { 231 232 #if defined(__powerpc64__) && BYTE_ORDER == BIG_ENDIAN 233 return (1); 234 #else 235 return (0); 236 #endif 237 } 238 239 static int 240 _powerpc64le_native(kvm_t *kd __unused) 241 { 242 243 #if defined(__powerpc64__) && BYTE_ORDER == LITTLE_ENDIAN 244 return (1); 245 #else 246 return (0); 247 #endif 248 } 249 250 static struct kvm_arch kvm_powerpc64 = { 251 .ka_probe = _powerpc64_probe, 252 .ka_initvtop = _powerpc64_initvtop, 253 .ka_freevtop = _powerpc64_freevtop, 254 .ka_kvatop = _powerpc64_kvatop, 255 .ka_native = _powerpc64_native, 256 }; 257 258 static struct kvm_arch kvm_powerpc64le = { 259 .ka_probe = _powerpc64le_probe, 260 .ka_initvtop = _powerpc64_initvtop, 261 .ka_freevtop = _powerpc64_freevtop, 262 .ka_kvatop = _powerpc64_kvatop, 263 .ka_native = _powerpc64le_native, 264 }; 265 266 KVM_ARCH(kvm_powerpc64); 267 KVM_ARCH(kvm_powerpc64le); 268