X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_emulator.c;h=20c6ecb6a387ac4b593b8c673356d1f0d059a9f3;hb=5d1bbcc86de011e3f0d115b6f10fd8645cdf855e;hp=024620e9871a0c238f8d0487e92bdbc1a63f83ca;hpb=5d0908c468453271f6de6bc786ee864b3308f9ef;p=palacios.git diff --git a/palacios/src/palacios/vmm_emulator.c b/palacios/src/palacios/vmm_emulator.c index 024620e..20c6ecb 100644 --- a/palacios/src/palacios/vmm_emulator.c +++ b/palacios/src/palacios/vmm_emulator.c @@ -11,7 +11,8 @@ * Copyright (c) 2008, The V3VEE Project * All rights reserved. * - * Author: Jack Lange + * Authors: Jack Lange + * Peter Dinda (full hook/string ops) * * This is free software. You are permitted to use, * redistribute, and modify it as specified in the file "V3VEE_LICENSE". @@ -19,456 +20,19 @@ #include #include -#include #include -#include #include +#include -#ifndef DEBUG_EMULATOR +#ifndef V3_CONFIG_DEBUG_EMULATOR #undef PrintDebug #define PrintDebug(fmt, args...) #endif -static int run_op(struct guest_info * info, v3_op_type_t op_type, addr_t src_addr, addr_t dst_addr, int src_op_size, int dst_op_size); - -// We emulate up to the next 4KB page boundry -static int emulate_string_write_op(struct guest_info * info, struct x86_instr * dec_instr, - addr_t write_gva, addr_t write_gpa, addr_t dst_addr, - int (*write_fn)(addr_t guest_addr, void * src, uint_t length, void * priv_data), - void * priv_data) { - uint_t emulation_length = 0; - uint_t emulation_iter_cnt = 0; - addr_t tmp_rcx = 0; - addr_t src_addr = 0; - - if (dec_instr->dst_operand.operand != write_gva) { - PrintError("Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p\n", - (void *)dec_instr->dst_operand.operand, (void *)write_gva); - return -1; - } - - emulation_length = ( (dec_instr->str_op_length < (0x1000 - PAGE_OFFSET_4KB(write_gva))) ? - dec_instr->str_op_length : - (0x1000 - PAGE_OFFSET_4KB(write_gva))); - - /* ** Fix emulation length so that it doesn't overrun over the src page either ** */ - emulation_iter_cnt = emulation_length / dec_instr->dst_operand.size; - tmp_rcx = emulation_iter_cnt; - - if (dec_instr->op_type == V3_OP_MOVS) { - - // figure out addresses here.... - if (info->mem_mode == PHYSICAL_MEM) { - if (guest_pa_to_host_va(info, dec_instr->src_operand.operand, &src_addr) == -1) { - PrintError("Could not translate write Source (Physical) to host VA\n"); - return -1; - } - } else { - if (guest_va_to_host_va(info, dec_instr->src_operand.operand, &src_addr) == -1) { - PrintError("Could not translate write Source (Virtual) to host VA\n"); - return -1; - } - } - - if (dec_instr->dst_operand.size == 1) { - movs8((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags)); - } else if (dec_instr->dst_operand.size == 2) { - movs16((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags)); - } else if (dec_instr->dst_operand.size == 4) { - movs32((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags)); -#ifdef __V3_64BIT__ - } else if (dec_instr->dst_operand.size == 8) { - movs64((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags)); -#endif - } else { - PrintError("Invalid operand length\n"); - return -1; - } - - info->vm_regs.rdi += emulation_length; - info->vm_regs.rsi += emulation_length; - - // RCX is only modified if the rep prefix is present - if (dec_instr->prefixes.rep == 1) { - info->vm_regs.rcx -= emulation_iter_cnt; - } - - } else if (dec_instr->op_type == V3_OP_STOS) { - - if (dec_instr->dst_operand.size == 1) { - stos8((addr_t *)&dst_addr, (addr_t *)&(info->vm_regs.rax), &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags)); - } else if (dec_instr->dst_operand.size == 2) { - stos16((addr_t *)&dst_addr, (addr_t *)&(info->vm_regs.rax), &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags)); - } else if (dec_instr->dst_operand.size == 4) { - stos32((addr_t *)&dst_addr, (addr_t *)&(info->vm_regs.rax), &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags)); -#ifdef __V3_64BIT__ - } else if (dec_instr->dst_operand.size == 8) { - stos64((addr_t *)&dst_addr, (addr_t *)&(info->vm_regs.rax), &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags)); -#endif - } else { - PrintError("Invalid operand length\n"); - return -1; - } - - info->vm_regs.rdi += emulation_length; - - // RCX is only modified if the rep prefix is present - if (dec_instr->prefixes.rep == 1) { - info->vm_regs.rcx -= emulation_iter_cnt; - } - - } else { - PrintError("Unimplemented String operation\n"); - return -1; - } - - if (write_fn(write_gpa, (void *)dst_addr, emulation_length, priv_data) != emulation_length) { - PrintError("Did not fully read hooked data\n"); - return -1; - } - - if (emulation_length == dec_instr->str_op_length) { - info->rip += dec_instr->instr_length; - } - - return emulation_length; -} - - -static int emulate_xchg_write_op(struct guest_info * info, struct x86_instr * dec_instr, - addr_t write_gva, addr_t write_gpa, addr_t dst_addr, - int (*write_fn)(addr_t guest_addr, void * src, uint_t length, void * priv_data), - void * priv_data) { - addr_t src_addr = 0; - addr_t em_dst_addr = 0; - int src_op_len = 0; - int dst_op_len = 0; - PrintDebug("Emulating XCHG write\n"); - - if (dec_instr->src_operand.type == MEM_OPERAND) { - if (info->shdw_pg_mode == SHADOW_PAGING) { - if (dec_instr->src_operand.operand != write_gva) { - PrintError("XCHG: Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p\n", - (void *)dec_instr->src_operand.operand, (void *)write_gva); - return -1; - } - } - - src_addr = dst_addr; - } else if (dec_instr->src_operand.type == REG_OPERAND) { - src_addr = dec_instr->src_operand.operand; - } else { - src_addr = (addr_t)&(dec_instr->src_operand.operand); - } - - - - if (dec_instr->dst_operand.type == MEM_OPERAND) { - if (info->shdw_pg_mode == SHADOW_PAGING) { - if (dec_instr->dst_operand.operand != write_gva) { - PrintError("XCHG: Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p\n", - (void *)dec_instr->dst_operand.operand, (void *)write_gva); - return -1; - } - } else { - //check that the operand (GVA) maps to the the faulting GPA - } - - em_dst_addr = dst_addr; - } else if (dec_instr->src_operand.type == REG_OPERAND) { - em_dst_addr = dec_instr->src_operand.operand; - } else { - em_dst_addr = (addr_t)&(dec_instr->src_operand.operand); - } - - dst_op_len = dec_instr->dst_operand.size; - src_op_len = dec_instr->src_operand.size; - - PrintDebug("Dst_Addr = %p, SRC operand = %p\n", - (void *)dst_addr, (void *)src_addr); - - - if (run_op(info, dec_instr->op_type, src_addr, em_dst_addr, src_op_len, dst_op_len) == -1) { - PrintError("Instruction Emulation Failed\n"); - return -1; - } - - if (write_fn(write_gpa, (void *)dst_addr, dst_op_len, priv_data) != dst_op_len) { - PrintError("Did not fully write hooked data\n"); - return -1; - } - - info->rip += dec_instr->instr_length; - - return dst_op_len; -} - - - -static int emulate_xchg_read_op(struct guest_info * info, struct x86_instr * dec_instr, - addr_t read_gva, addr_t read_gpa, addr_t src_addr, - int (*read_fn)(addr_t guest_addr, void * dst, uint_t length, void * priv_data), - int (*write_fn)(addr_t guest_addr, void * src, uint_t length, void * priv_data), - void * priv_data) { - addr_t em_src_addr = 0; - addr_t em_dst_addr = 0; - int src_op_len = 0; - int dst_op_len = 0; - - PrintDebug("Emulating XCHG Read\n"); - - if (dec_instr->src_operand.type == MEM_OPERAND) { - if (dec_instr->src_operand.operand != read_gva) { - PrintError("XCHG: Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p\n", - (void *)dec_instr->src_operand.operand, (void *)read_gva); - return -1; - } - - em_src_addr = src_addr; - } else if (dec_instr->src_operand.type == REG_OPERAND) { - em_src_addr = dec_instr->src_operand.operand; - } else { - em_src_addr = (addr_t)&(dec_instr->src_operand.operand); - } - - - - if (dec_instr->dst_operand.type == MEM_OPERAND) { - if (info->shdw_pg_mode == SHADOW_PAGING) { - if (dec_instr->dst_operand.operand != read_gva) { - PrintError("XCHG: Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p\n", - (void *)dec_instr->dst_operand.operand, (void *)read_gva); - return -1; - } - } else { - //check that the operand (GVA) maps to the the faulting GPA - } - - em_dst_addr = src_addr; - } else if (dec_instr->src_operand.type == REG_OPERAND) { - em_dst_addr = dec_instr->src_operand.operand; - } else { - em_dst_addr = (addr_t)&(dec_instr->src_operand.operand); - } - - dst_op_len = dec_instr->dst_operand.size; - src_op_len = dec_instr->src_operand.size; - - PrintDebug("Dst_Addr = %p, SRC operand = %p\n", - (void *)em_dst_addr, (void *)em_src_addr); - - - if (read_fn(read_gpa, (void *)src_addr, src_op_len, priv_data) != src_op_len) { - PrintError("Did not fully read hooked data\n"); - return -1; - } - - if (run_op(info, dec_instr->op_type, em_src_addr, em_dst_addr, src_op_len, dst_op_len) == -1) { - PrintError("Instruction Emulation Failed\n"); - return -1; - } - - if (write_fn(read_gpa, (void *)src_addr, dst_op_len, priv_data) != dst_op_len) { - PrintError("Did not fully write hooked data\n"); - return -1; - } - - info->rip += dec_instr->instr_length; - - return dst_op_len; -} - - - - -int v3_emulate_write_op(struct guest_info * info, addr_t write_gva, addr_t write_gpa, addr_t dst_addr, - int (*write_fn)(addr_t guest_addr, void * src, uint_t length, void * priv_data), - void * priv_data) { - struct x86_instr dec_instr; - uchar_t instr[15]; - int ret = 0; - addr_t src_addr = 0; - int src_op_len = 0; - int dst_op_len = 0; - - PrintDebug("Emulating Write for instruction at %p\n", (void *)(addr_t)(info->rip)); - PrintDebug("GVA=%p Dst_Addr=%p\n", (void *)write_gva, (void *)dst_addr); - - if (info->mem_mode == PHYSICAL_MEM) { - ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr); - } else { - ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr); - } - - if (ret == -1) { - return -1; - } - - if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) { - PrintError("Decoding Error\n"); - // Kick off single step emulator - return -1; - } - - /* - * Instructions needing to be special cased.... * - */ - if (dec_instr.is_str_op) { - return emulate_string_write_op(info, &dec_instr, write_gva, write_gpa, dst_addr, write_fn, priv_data); - } else if (dec_instr.op_type == V3_OP_XCHG) { - return emulate_xchg_write_op(info, &dec_instr, write_gva, write_gpa, dst_addr, write_fn, priv_data); - } - - - if (info->shdw_pg_mode == SHADOW_PAGING) { - if ((dec_instr.dst_operand.type != MEM_OPERAND) || - (dec_instr.dst_operand.operand != write_gva)) { - PrintError("Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p\n", - (void *)dec_instr.dst_operand.operand, (void *)write_gva); - return -1; - } - } else { - //check that the operand (GVA) maps to the the faulting GPA - } - - - if (dec_instr.src_operand.type == MEM_OPERAND) { - if (info->mem_mode == PHYSICAL_MEM) { - if (guest_pa_to_host_va(info, dec_instr.src_operand.operand, &src_addr) == -1) { - PrintError("Could not translate write Source (Physical) to host VA\n"); - return -1; - } - } else { - if (guest_va_to_host_va(info, dec_instr.src_operand.operand, &src_addr) == -1) { - PrintError("Could not translate write Source (Virtual) to host VA\n"); - return -1; - } - } - } else if (dec_instr.src_operand.type == REG_OPERAND) { - src_addr = dec_instr.src_operand.operand; - } else { - src_addr = (addr_t)&(dec_instr.src_operand.operand); - } - - dst_op_len = dec_instr.dst_operand.size; - src_op_len = dec_instr.src_operand.size; - - PrintDebug("Dst_Addr = %p, SRC operand = %p\n", - (void *)dst_addr, (void *)src_addr); - - - if (run_op(info, dec_instr.op_type, src_addr, dst_addr, src_op_len, dst_op_len) == -1) { - PrintError("Instruction Emulation Failed\n"); - return -1; - } - - if (write_fn(write_gpa, (void *)dst_addr, dst_op_len, priv_data) != dst_op_len) { - PrintError("Did not fully write hooked data\n"); - return -1; - } - - info->rip += dec_instr.instr_length; - - return dst_op_len; -} - - -int v3_emulate_read_op(struct guest_info * info, addr_t read_gva, addr_t read_gpa, addr_t src_addr, - int (*read_fn)(addr_t guest_addr, void * dst, uint_t length, void * priv_data), - int (*write_fn)(addr_t guest_addr, void * src, uint_t length, void * priv_data), - void * priv_data) { - struct x86_instr dec_instr; - uchar_t instr[15]; - int ret = 0; - addr_t dst_addr = 0; - int src_op_len = 0; - int dst_op_len = 0; - - PrintDebug("Emulating Read for instruction at %p\n", (void *)(addr_t)(info->rip)); - PrintDebug("GVA=%p\n", (void *)read_gva); - - if (info->mem_mode == PHYSICAL_MEM) { - ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr); - } else { - ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr); - } - - if (ret == -1) { - PrintError("Could not read instruction for Emulated Read at %p\n", (void *)(addr_t)(info->rip)); - return -1; - } - - - if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) { - PrintError("Decoding Error\n"); - // Kick off single step emulator - return -1; - } - - if (dec_instr.is_str_op) { - PrintError("String operations not implemented on fully hooked regions\n"); - return -1; - } else if (dec_instr.op_type == V3_OP_XCHG) { - return emulate_xchg_read_op(info, &dec_instr, read_gva, read_gpa, src_addr, read_fn, write_fn, priv_data); - } - - if (info->shdw_pg_mode == SHADOW_PAGING) { - if ((dec_instr.src_operand.type != MEM_OPERAND) || - (dec_instr.src_operand.operand != read_gva)) { - PrintError("Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p operand_type=%d\n", - (void *)dec_instr.src_operand.operand, (void *)read_gva, dec_instr.src_operand.type); - return -1; - } - } else { - //check that the operand (GVA) maps to the the faulting GPA - } - - if (dec_instr.dst_operand.type == MEM_OPERAND) { - if (info->mem_mode == PHYSICAL_MEM) { - if (guest_pa_to_host_va(info, dec_instr.dst_operand.operand, &dst_addr) == -1) { - PrintError("Could not translate Read Destination (Physical) to host VA\n"); - return -1; - } - } else { - if (guest_va_to_host_va(info, dec_instr.dst_operand.operand, &dst_addr) == -1) { - PrintError("Could not translate Read Destination (Virtual) to host VA\n"); - return -1; - } - } - } else if (dec_instr.dst_operand.type == REG_OPERAND) { - dst_addr = dec_instr.dst_operand.operand; - } else { - dst_addr = (addr_t)&(dec_instr.dst_operand.operand); - } - - src_op_len = dec_instr.src_operand.size; - dst_op_len = dec_instr.dst_operand.size; - - PrintDebug("Dst_Addr = %p, SRC Addr = %p\n", - (void *)dst_addr, (void *)src_addr); - - if (read_fn(read_gpa, (void *)src_addr, src_op_len, priv_data) != src_op_len) { - PrintError("Did not fully read hooked data\n"); - return -1; - } - - if (run_op(info, dec_instr.op_type, src_addr, dst_addr, src_op_len, dst_op_len) == -1) { - PrintError("Instruction Emulation Failed\n"); - return -1; - } - - info->rip += dec_instr.instr_length; - - return src_op_len; -} - - - - - - -static int run_op(struct guest_info * info, v3_op_type_t op_type, addr_t src_addr, addr_t dst_addr, int src_op_size, int dst_op_size) { +static int run_op(struct guest_info * info, v3_op_type_t op_type, + addr_t src_addr, addr_t dst_addr, + int src_op_size, int dst_op_size) { if (src_op_size == 1) { PrintDebug("Executing 8 bit instruction\n"); @@ -737,3 +301,130 @@ static int run_op(struct guest_info * info, v3_op_type_t op_type, addr_t src_add return 0; } + + + +/* Returns the number of bytes written, or -1 if there is an error */ +static int run_str_op(struct guest_info * core, struct x86_instr * instr, + addr_t src_addr, addr_t dst_addr, + int op_size, int rep_cnt) { + + addr_t tmp_rcx = rep_cnt; + int emulation_length = op_size * rep_cnt; + struct rflags * flags_reg = (struct rflags *)&(core->ctrl_regs.rflags); + + + PrintDebug("Emulation_len=%d, tmp_rcx=%d\n", emulation_length, (uint_t)tmp_rcx); + + + if (instr->op_type == V3_OP_MOVS) { + if (op_size== 1) { + movs8((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags)); + } else if (op_size == 2) { + movs16((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags)); + } else if (op_size == 4) { + movs32((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags)); +#ifdef __V3_64BIT__ + } else if (op_size == 8) { + movs64((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags)); +#endif + } else { + PrintError("Invalid operand length\n"); + return -1; + } + + if (flags_reg->df == 0) { + core->vm_regs.rdi += emulation_length; + core->vm_regs.rsi += emulation_length; + } else { + core->vm_regs.rdi -= emulation_length; + core->vm_regs.rsi -= emulation_length; + } + + // RCX is only modified if the rep prefix is present + if (instr->prefixes.rep == 1) { + core->vm_regs.rcx -= rep_cnt; + } + + } else if (instr->op_type == V3_OP_STOS) { + if (op_size == 1) { + stos8((addr_t *)&dst_addr, (addr_t *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags)); + } else if (op_size == 2) { + stos16((addr_t *)&dst_addr, (addr_t *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags)); + } else if (op_size == 4) { + stos32((addr_t *)&dst_addr, (addr_t *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags)); +#ifdef __V3_64BIT__ + } else if (op_size == 8) { + stos64((addr_t *)&dst_addr, (addr_t *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags)); +#endif + } else { + PrintError("Invalid operand length\n"); + return -1; + } + + + + if (flags_reg->df == 0) { + core->vm_regs.rdi += emulation_length; + } else { + core->vm_regs.rdi -= emulation_length; + } + + // RCX is only modified if the rep prefix is present + if (instr->prefixes.rep == 1) { + core->vm_regs.rcx -= rep_cnt; + } + } else { + PrintError("Unimplemented String operation\n"); + return -1; + } + + return emulation_length; +} + + + +int v3_emulate(struct guest_info * core, struct x86_instr * instr, + int mem_op_size, addr_t mem_hva_src, addr_t mem_hva_dst) { + + addr_t src_hva = 0; + addr_t dst_hva = 0; + + + if (instr->src_operand.type == MEM_OPERAND) { + src_hva = mem_hva_src; + } else if (instr->src_operand.type == REG_OPERAND) { + src_hva = instr->src_operand.operand; + } else { + src_hva = (addr_t)&(instr->src_operand.operand); + } + + if (instr->dst_operand.type == MEM_OPERAND) { + dst_hva = mem_hva_dst; + } else if (instr->dst_operand.type == REG_OPERAND) { + dst_hva = instr->dst_operand.operand; + } else { + dst_hva = (addr_t)&(instr->dst_operand.operand); + } + + + if (instr->is_str_op == 0) { + int src_op_len = instr->src_operand.size; + int dst_op_len = instr->dst_operand.size; + + run_op(core, instr->op_type, src_hva, dst_hva, src_op_len, dst_op_len); + + return dst_op_len; + } else { + // String Operation + int rep_cnt = 0; + + /* Both src and dst operand sizes should be identical */ + rep_cnt = mem_op_size / instr->src_operand.size; + + return run_str_op(core, instr, src_hva, dst_hva, instr->src_operand.size, rep_cnt); + } + + + return -1; +}