palacios/src/palacios/vmm_emulator.c

   1 /*
   2  * This file is part of the Palacios Virtual Machine Monitor developed
   3  * by the V3VEE Project with funding from the United States National
   4  * Science Foundation and the Department of Energy.
   5  *
   6  * The V3VEE Project is a joint project between Northwestern University
   7  * and the University of New Mexico.  You can find out more at
   8  * http://www.v3vee.org
   9  *
  10  * Copyright (c) 2008, Jack Lange <jarusl@cs.northwestern.edu>
  11  * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
  12  * All rights reserved.
  13  *
  14  * Authors: Jack Lange <jarusl@cs.northwestern.edu>
  15  *          Peter Dinda <pdinda@northwestern.edu> (full hook/string ops)
  16  *
  17  * This is free software.  You are permitted to use,
  18  * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
  19  */
  20
  21 #include <palacios/vmm.h>
  22 #include <palacios/vmm_emulator.h>
  23 #include <palacios/vmm_decoder.h>
  24 #include <palacios/vmm_instr_emulator.h>
  25 #include <palacios/vmm_ctrl_regs.h>
  26
  27 #ifndef V3_CONFIG_DEBUG_EMULATOR
  28 #undef PrintDebug
  29 #define PrintDebug(fmt, args...)
  30 #endif
  31
  32
  33 static int run_op(struct guest_info * info, v3_op_type_t op_type,
  34                   addr_t src_addr, addr_t dst_addr,
  35                   int src_op_size, int dst_op_size) {
  36
  37     if (src_op_size == 1) {
  38         PrintDebug(info->vm_info, info, "Executing 8 bit instruction\n");
  39
  40         switch (op_type) {
  41             case V3_OP_ADC:
  42                 adc8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
  43                 break;
  44             case V3_OP_ADD:
  45                 add8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
  46                 break;
  47             case V3_OP_AND:
  48                 and8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
  49                 break;
  50             case V3_OP_OR:
  51                 or8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
  52                 break;
  53             case V3_OP_XOR:
  54                 xor8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
  55                 break;
  56             case V3_OP_SUB:
  57                 sub8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
  58                 break;
  59
  60             case V3_OP_MOV:
  61                 mov8((addr_t *)dst_addr, (addr_t *)src_addr);
  62                 break;
  63
  64             case V3_OP_MOVZX:
  65                 movzx8((addr_t *)dst_addr, (addr_t *)src_addr, dst_op_size);
  66                 break;
  67             case V3_OP_MOVSX:
  68                 movsx8((addr_t *)dst_addr, (addr_t *)src_addr, dst_op_size);
  69                 break;
  70
  71             case V3_OP_NOT:
  72                 not8((addr_t *)dst_addr);
  73                 break;
  74             case V3_OP_XCHG:
  75                 xchg8((addr_t *)dst_addr, (addr_t *)src_addr);
  76                 break;
  77
  78
  79             case V3_OP_INC:
  80                 inc8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
  81                 break;
  82             case V3_OP_DEC:
  83                 dec8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
  84                 break;
  85             case V3_OP_NEG:
  86                 neg8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
  87                 break;
  88             case V3_OP_SETB:
  89                 setb8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
  90                 break;
  91             case V3_OP_SETBE:
  92                 setbe8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
  93                 break;
  94             case V3_OP_SETL:
  95                 setl8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
  96                 break;
  97             case V3_OP_SETLE:
  98                 setle8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
  99                 break;
 100             case V3_OP_SETNB:
 101                 setnb8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 102                 break;
 103             case V3_OP_SETNBE:
 104                 setnbe8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 105                 break;
 106             case V3_OP_SETNL:
 107                 setnl8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 108                 break;
 109             case V3_OP_SETNLE:
 110                 setnle8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 111                 break;
 112             case V3_OP_SETNO:
 113                 setno8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 114                 break;
 115             case V3_OP_SETNP:
 116                 setnp8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 117                 break;
 118             case V3_OP_SETNS:
 119                 setns8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 120                 break;
 121             case V3_OP_SETNZ:
 122                 setnz8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 123                 break;
 124             case V3_OP_SETO:
 125                 seto8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 126                 break;
 127             case V3_OP_SETP:
 128                 setp8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 129                 break;
 130             case V3_OP_SETS:
 131                 sets8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 132                 break;
 133             case V3_OP_SETZ:
 134                 setz8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 135                 break;
 136
 137             default:
 138                 PrintError(info->vm_info, info, "Unknown 8 bit instruction\n");
 139                 return -1;
 140         }
 141
 142     } else if (src_op_size == 2) {
 143         PrintDebug(info->vm_info, info, "Executing 16 bit instruction\n");
 144
 145         switch (op_type) {
 146             case V3_OP_ADC:
 147                 adc16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 148                 break;
 149             case V3_OP_ADD:
 150                 add16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 151                 break;
 152             case V3_OP_AND:
 153                 and16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 154                 break;
 155             case V3_OP_OR:
 156                 or16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 157                 break;
 158             case V3_OP_XOR:
 159                 xor16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 160                 break;
 161             case V3_OP_SUB:
 162                 sub16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 163                 break;
 164
 165
 166             case V3_OP_INC:
 167                 inc16((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 168                 break;
 169             case V3_OP_DEC:
 170                 dec16((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 171                 break;
 172             case V3_OP_NEG:
 173                 neg16((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 174                 break;
 175
 176             case V3_OP_MOV:
 177                 mov16((addr_t *)dst_addr, (addr_t *)src_addr);
 178                 break;
 179             case V3_OP_MOVZX:
 180                 movzx16((addr_t *)dst_addr, (addr_t *)src_addr, dst_op_size);
 181                 break;
 182             case V3_OP_MOVSX:
 183                 movsx16((addr_t *)dst_addr, (addr_t *)src_addr, dst_op_size);
 184                 break;
 185             case V3_OP_NOT:
 186                 not16((addr_t *)dst_addr);
 187                 break;
 188             case V3_OP_XCHG:
 189                 xchg16((addr_t *)dst_addr, (addr_t *)src_addr);
 190                 break;
 191
 192             default:
 193                 PrintError(info->vm_info, info, "Unknown 16 bit instruction\n");
 194                 return -1;
 195         }
 196
 197     } else if (src_op_size == 4) {
 198         PrintDebug(info->vm_info, info, "Executing 32 bit instruction\n");
 199
 200         switch (op_type) {
 201             case V3_OP_ADC:
 202                 adc32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 203                 break;
 204             case V3_OP_ADD:
 205                 add32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 206                 break;
 207             case V3_OP_AND:
 208                 and32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 209                 break;
 210             case V3_OP_OR:
 211                 or32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 212                 break;
 213             case V3_OP_XOR:
 214                 xor32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 215                 break;
 216             case V3_OP_SUB:
 217                 sub32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 218                 break;
 219
 220             case V3_OP_INC:
 221                 inc32((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 222                 break;
 223             case V3_OP_DEC:
 224                 dec32((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 225                 break;
 226             case V3_OP_NEG:
 227                 neg32((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 228                 break;
 229
 230             case V3_OP_MOV:
 231                 mov32((addr_t *)dst_addr, (addr_t *)src_addr);
 232                 break;
 233
 234             case V3_OP_NOT:
 235                 not32((addr_t *)dst_addr);
 236                 break;
 237             case V3_OP_XCHG:
 238                 xchg32((addr_t *)dst_addr, (addr_t *)src_addr);
 239                 break;
 240
 241             default:
 242                 PrintError(info->vm_info, info, "Unknown 32 bit instruction\n");
 243                 return -1;
 244         }
 245
 246 #ifdef __V3_64BIT__
 247     } else if (src_op_size == 8) {
 248         PrintDebug(info->vm_info, info, "Executing 64 bit instruction\n");
 249
 250         switch (op_type) {
 251             case V3_OP_ADC:
 252                 adc64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 253                 break;
 254             case V3_OP_ADD:
 255                 add64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 256                 break;
 257             case V3_OP_AND:
 258                 and64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 259                 break;
 260             case V3_OP_OR:
 261                 or64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 262                 break;
 263             case V3_OP_XOR:
 264                 xor64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 265                 break;
 266             case V3_OP_SUB:
 267                 sub64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
 268                 break;
 269
 270             case V3_OP_INC:
 271                 inc64((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 272                 break;
 273             case V3_OP_DEC:
 274                 dec64((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 275                 break;
 276             case V3_OP_NEG:
 277                 neg64((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
 278                 break;
 279
 280             case V3_OP_MOV:
 281                 mov64((addr_t *)dst_addr, (addr_t *)src_addr);
 282                 break;
 283
 284             case V3_OP_NOT:
 285                 not64((addr_t *)dst_addr);
 286                 break;
 287             case V3_OP_XCHG:
 288                 xchg64((addr_t *)dst_addr, (addr_t *)src_addr);
 289                 break;
 290
 291             default:
 292                 PrintError(info->vm_info, info, "Unknown 64 bit instruction\n");
 293                 return -1;
 294         }
 295 #endif
 296
 297     } else {
 298         PrintError(info->vm_info, info, "Invalid Operation Size\n");
 299         return -1;
 300     }
 301
 302     return 0;
 303 }
 304
 305
 306
 307 /* Returns the number of bytes written, or -1 if there is an error */
 308 static int run_str_op(struct guest_info * core, struct x86_instr * instr,
 309                       addr_t src_addr, addr_t dst_addr,
 310                       int op_size, int rep_cnt) {
 311
 312     addr_t tmp_rcx = rep_cnt;
 313     int emulation_length = op_size * rep_cnt;
 314     struct rflags * flags_reg = (struct rflags *)&(core->ctrl_regs.rflags);
 315
 316
 317     PrintDebug(core->vm_info, core, "Emulation_len=%d, tmp_rcx=%d\n", emulation_length, (uint_t)tmp_rcx);
 318
 319
 320     if (instr->op_type == V3_OP_MOVS) {
 321         if (op_size== 1) {
 322             movs8((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
 323         } else if (op_size == 2) {
 324             movs16((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
 325         } else if (op_size == 4) {
 326             movs32((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
 327 #ifdef __V3_64BIT__
 328         } else if (op_size == 8) {
 329             movs64((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
 330 #endif
 331         } else {
 332             PrintError(core->vm_info, core, "Invalid operand length\n");
 333             return -1;
 334         }
 335
 336         if (flags_reg->df == 0) {
 337             core->vm_regs.rdi += emulation_length;
 338             core->vm_regs.rsi += emulation_length;
 339         } else {
 340             core->vm_regs.rdi -= emulation_length;
 341             core->vm_regs.rsi -= emulation_length;
 342         }
 343
 344         // RCX is only modified if the rep prefix is present
 345         if (instr->prefixes.rep == 1) {
 346             core->vm_regs.rcx -= rep_cnt;
 347         }
 348
 349      } else if (instr->op_type == V3_OP_STOS) {
 350         if (op_size == 1) {
 351             stos8((addr_t *)&dst_addr, (addr_t  *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
 352         } else if (op_size == 2) {
 353             stos16((addr_t *)&dst_addr, (addr_t  *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
 354         } else if (op_size == 4) {
 355             stos32((addr_t *)&dst_addr, (addr_t  *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
 356 #ifdef __V3_64BIT__
 357         } else if (op_size == 8) {
 358             stos64((addr_t *)&dst_addr, (addr_t  *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
 359 #endif
 360         } else {
 361             PrintError(core->vm_info, core, "Invalid operand length\n");
 362             return -1;
 363         }
 364
 365
 366
 367         if (flags_reg->df == 0) {
 368             core->vm_regs.rdi += emulation_length;
 369         } else {
 370             core->vm_regs.rdi -= emulation_length;
 371         }
 372
 373         // RCX is only modified if the rep prefix is present
 374         if (instr->prefixes.rep == 1) {
 375             core->vm_regs.rcx -= rep_cnt;
 376         }
 377     } else {
 378         PrintError(core->vm_info, core, "Unimplemented String operation\n");
 379         return -1;
 380     }
 381
 382     return emulation_length;
 383 }
 384
 385
 386
 387 int v3_emulate(struct guest_info * core, struct x86_instr * instr,
 388                int mem_op_size, addr_t mem_hva_src, addr_t mem_hva_dst) {
 389
 390     addr_t src_hva = 0;
 391     addr_t dst_hva = 0;
 392
 393
 394     if (instr->src_operand.type == MEM_OPERAND) {
 395         src_hva = mem_hva_src;
 396     } else if (instr->src_operand.type == REG_OPERAND) {
 397         src_hva = instr->src_operand.operand;
 398     } else {
 399         src_hva = (addr_t)&(instr->src_operand.operand);
 400     }
 401
 402     if (instr->dst_operand.type == MEM_OPERAND) {
 403         dst_hva = mem_hva_dst;
 404     } else if (instr->dst_operand.type == REG_OPERAND) {
 405         dst_hva = instr->dst_operand.operand;
 406     } else {
 407         dst_hva = (addr_t)&(instr->dst_operand.operand);
 408     }
 409
 410
 411     if (instr->is_str_op == 0) {
 412         int src_op_len = instr->src_operand.size;
 413         int dst_op_len = instr->dst_operand.size;
 414
 415         run_op(core, instr->op_type, src_hva, dst_hva, src_op_len, dst_op_len);
 416
 417         return dst_op_len;
 418     } else {
 419         // String Operation
 420         int rep_cnt = 0;
 421
 422         /* Both src and dst operand sizes should be identical */
 423         rep_cnt = mem_op_size / instr->src_operand.size;
 424
 425         return run_str_op(core, instr, src_hva, dst_hva, instr->src_operand.size, rep_cnt);
 426     }
 427
 428
 429     return -1;
 430 }