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/*
* Copyright 2019 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include <errno.h>
#include <fcntl.h>
#include <linux/memfd.h>
#include <pthread.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <time.h>
#include <unistd.h>
#include "crosvm.h"
#ifndef F_LINUX_SPECIFIC_BASE
#define F_LINUX_SPECIFIC_BASE 1024
#endif
#ifndef F_ADD_SEALS
#define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9)
#endif
#ifndef F_SEAL_SHRINK
#define F_SEAL_SHRINK 0x0002
#endif
#define KILL_ADDRESS 0x3f9
#define ASYNC_ADDRESS 0x500
int g_kill_evt;
int got_error = 0;
void *vcpu_thread(void *arg) {
struct crosvm_vcpu *vcpu = arg;
struct crosvm_vcpu_event evt;
while (crosvm_vcpu_wait(vcpu, &evt) == 0) {
if (evt.kind == CROSVM_VCPU_EVENT_KIND_INIT) {
struct kvm_sregs sregs;
crosvm_vcpu_get_sregs(vcpu, &sregs);
sregs.cs.base = 0;
sregs.cs.selector = 0;
sregs.es.base = KILL_ADDRESS;
sregs.es.selector = 0;
crosvm_vcpu_set_sregs(vcpu, &sregs);
struct kvm_regs regs;
crosvm_vcpu_get_regs(vcpu, ®s);
regs.rip = 0x1000;
regs.rax = 2;
regs.rbx = 7;
regs.rflags = 2;
crosvm_vcpu_set_regs(vcpu, ®s);
}
if (evt.kind == CROSVM_VCPU_EVENT_KIND_IO_ACCESS) {
if (evt.io_access.address_space == CROSVM_ADDRESS_SPACE_IOPORT &&
evt.io_access.address == ASYNC_ADDRESS &&
evt.io_access.is_write &&
evt.io_access.length == 1) {
int ret;
if (!evt.io_access.no_resume) {
fprintf(stderr, "should have been told not to resume\n");
got_error = 1;
}
ret = crosvm_vcpu_wait(vcpu, &evt);
if (ret == 0) {
if (evt.kind != CROSVM_VCPU_EVENT_KIND_IO_ACCESS ||
evt.io_access.address_space !=
CROSVM_ADDRESS_SPACE_IOPORT ||
evt.io_access.address != ASYNC_ADDRESS ||
!evt.io_access.is_write ||
!evt.io_access.no_resume ||
evt.io_access.length != 1) {
fprintf(stderr, "got unexpected wait #1 result\n");
got_error = 1;
}
} else {
fprintf(stderr, "crosvm_vcpu_wait() #1 failed: %d\n", ret);
got_error = 1;
}
ret = crosvm_vcpu_wait(vcpu, &evt);
if (ret == 0) {
if (evt.kind != CROSVM_VCPU_EVENT_KIND_IO_ACCESS ||
evt.io_access.address_space !=
CROSVM_ADDRESS_SPACE_IOPORT ||
evt.io_access.address != ASYNC_ADDRESS ||
!evt.io_access.is_write ||
!evt.io_access.no_resume ||
evt.io_access.length != 1) {
fprintf(stderr, "got unexpected wait #2 result\n");
got_error = 1;
}
} else {
fprintf(stderr, "crosvm_vcpu_wait() #2 failed: %d\n", ret);
got_error = 1;
}
// skip the crosvm_vcpu_resume()
continue;
}
if (evt.io_access.address_space == CROSVM_ADDRESS_SPACE_IOPORT &&
evt.io_access.address == KILL_ADDRESS &&
evt.io_access.is_write &&
evt.io_access.length == 1 &&
evt.io_access.data[0] == 1)
{
uint64_t dummy = 1;
write(g_kill_evt, &dummy, sizeof(dummy));
return NULL;
}
}
crosvm_vcpu_resume(vcpu);
}
return NULL;
}
int main(int argc, char** argv) {
const uint8_t code[] = {
/*
B007 mov al,0x7
BA0005 mov dx,0x500
EE out dx,al
EE out dx,al
EE out dx,al
BAF903 mov dx,0x3f9
B001 mov al,0x1
EE out dx,al
F4 hlt
*/
0xb0, 0x7,
0xba, (ASYNC_ADDRESS & 0xFF), ((ASYNC_ADDRESS >> 8) & 0xFF),
0xee,
0xee,
0xee,
0xba, (KILL_ADDRESS & 0xFF), ((KILL_ADDRESS >> 8) & 0xFF),
0xb0, 0x01,
0xee,
0xf4
};
struct crosvm *crosvm;
int ret = crosvm_connect(&crosvm);
if (ret) {
fprintf(stderr, "failed to connect to crosvm: %d\n", ret);
return 1;
}
/*
* Not strictly necessary, but demonstrates we can have as many connections
* as we please.
*/
struct crosvm *extra_crosvm;
ret = crosvm_new_connection(crosvm, &extra_crosvm);
if (ret) {
fprintf(stderr, "failed to make new socket: %d\n", ret);
return 1;
}
/* We needs this eventfd to know when to exit before being killed. */
g_kill_evt = crosvm_get_shutdown_eventfd(crosvm);
if (g_kill_evt < 0) {
fprintf(stderr, "failed to get kill eventfd: %d\n", g_kill_evt);
return 1;
}
ret = crosvm_reserve_async_write_range(crosvm, CROSVM_ADDRESS_SPACE_IOPORT,
ASYNC_ADDRESS, 1);
if (ret) {
fprintf(stderr, "failed to reserve async ioport range: %d\n", ret);
return 1;
}
ret = crosvm_reserve_range(crosvm, CROSVM_ADDRESS_SPACE_IOPORT,
KILL_ADDRESS, 1);
if (ret) {
fprintf(stderr, "failed to reserve kill ioport range: %d\n", ret);
return 1;
}
int mem_size = 0x2000;
int mem_fd = syscall(SYS_memfd_create, "guest_mem",
MFD_CLOEXEC | MFD_ALLOW_SEALING);
if (mem_fd < 0) {
fprintf(stderr, "failed to create guest memfd: %d\n", errno);
return 1;
}
ret = ftruncate(mem_fd, mem_size);
if (ret) {
fprintf(stderr, "failed to set size of guest memory: %d\n", errno);
return 1;
}
uint8_t *mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_SHARED,
mem_fd, 0x1000);
if (mem == MAP_FAILED) {
fprintf(stderr, "failed to mmap guest memory: %d\n", errno);
return 1;
}
fcntl(mem_fd, F_ADD_SEALS, F_SEAL_SHRINK);
memcpy(mem, code, sizeof(code));
struct crosvm_memory *mem_obj;
ret = crosvm_create_memory(crosvm, mem_fd, 0x1000, 0x1000, 0x1000, false,
false, &mem_obj);
if (ret) {
fprintf(stderr, "failed to create memory in crosvm: %d\n", ret);
return 1;
}
/* get and creat a thread for each vcpu */
struct crosvm_vcpu *vcpus[32];
pthread_t vcpu_threads[32];
uint32_t vcpu_count;
for (vcpu_count = 0; vcpu_count < 32; vcpu_count++) {
ret = crosvm_get_vcpu(crosvm, vcpu_count, &vcpus[vcpu_count]);
if (ret == -ENOENT)
break;
if (ret) {
fprintf(stderr, "error while getting all vcpus: %d\n", ret);
return 1;
}
pthread_create(&vcpu_threads[vcpu_count], NULL, vcpu_thread,
vcpus[vcpu_count]);
}
ret = crosvm_start(extra_crosvm);
if (ret) {
fprintf(stderr, "failed to tell crosvm to start: %d\n", ret);
return 1;
}
/* Wait for crosvm to request that we exit otherwise we will be killed. */
uint64_t dummy;
read(g_kill_evt, &dummy, 8);
ret = crosvm_destroy_memory(crosvm, &mem_obj);
if (ret) {
fprintf(stderr, "failed to destroy memory in crosvm: %d\n", ret);
return 1;
}
ret = crosvm_reserve_async_write_range(crosvm, CROSVM_ADDRESS_SPACE_IOPORT,
ASYNC_ADDRESS, 0);
if (ret) {
fprintf(stderr, "failed to unreserve async ioport range: %d\n", ret);
return 1;
}
ret = crosvm_reserve_range(crosvm, CROSVM_ADDRESS_SPACE_IOPORT,
KILL_ADDRESS, 0);
if (ret) {
fprintf(stderr, "failed to unreserve kill ioport range: %d\n", ret);
return 1;
}
if (got_error) {
fprintf(stderr, "vm ran to completion but with an error\n");
return 1;
}
return 0;
}
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