// https://syzkaller.appspot.com/bug?id=8af2597890938b642c3bf44a85859691fb9d5cfa
// autogenerated by syzkaller (http://github.com/google/syzkaller)

#define _GNU_SOURCE
#include <endian.h>
#include <errno.h>
#include <linux/net.h>
#include <netinet/in.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <sys/prctl.h>
#include <sys/socket.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

__attribute__((noreturn)) static void doexit(int status)
{
  volatile unsigned i;
  syscall(__NR_exit_group, status);
  for (i = 0;; i++) {
  }
}
#include <stdint.h>
#include <string.h>

const int kFailStatus = 67;
const int kRetryStatus = 69;

static void fail(const char* msg, ...)
{
  int e = errno;
  va_list args;
  va_start(args, msg);
  vfprintf(stderr, msg, args);
  va_end(args);
  fprintf(stderr, " (errno %d)\n", e);
  doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus);
}

#define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1)

#define BITMASK_LEN_OFF(type, bf_off, bf_len)                                  \
  (type)(BITMASK_LEN(type, (bf_len)) << (bf_off))

#define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len)                      \
  if ((bf_off) == 0 && (bf_len) == 0) {                                        \
    *(type*)(addr) = (type)(val);                                              \
  } else {                                                                     \
    type new_val = *(type*)(addr);                                             \
    new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len));                     \
    new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off);          \
    *(type*)(addr) = new_val;                                                  \
  }

struct csum_inet {
  uint32_t acc;
};

static void csum_inet_init(struct csum_inet* csum)
{
  csum->acc = 0;
}

static void csum_inet_update(struct csum_inet* csum, const uint8_t* data,
                             size_t length)
{
  if (length == 0)
    return;

  size_t i;
  for (i = 0; i < length - 1; i += 2)
    csum->acc += *(uint16_t*)&data[i];

  if (length & 1)
    csum->acc += (uint16_t)data[length - 1];

  while (csum->acc > 0xffff)
    csum->acc = (csum->acc & 0xffff) + (csum->acc >> 16);
}

static uint16_t csum_inet_digest(struct csum_inet* csum)
{
  return ~csum->acc;
}

static uint64_t current_time_ms()
{
  struct timespec ts;

  if (clock_gettime(CLOCK_MONOTONIC, &ts))
    fail("clock_gettime failed");
  return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
}

#define XT_TABLE_SIZE 1536
#define XT_MAX_ENTRIES 10

struct xt_counters {
  uint64_t pcnt, bcnt;
};

struct ipt_getinfo {
  char name[32];
  unsigned int valid_hooks;
  unsigned int hook_entry[5];
  unsigned int underflow[5];
  unsigned int num_entries;
  unsigned int size;
};

struct ipt_get_entries {
  char name[32];
  unsigned int size;
  void* entrytable[XT_TABLE_SIZE / sizeof(void*)];
};

struct ipt_replace {
  char name[32];
  unsigned int valid_hooks;
  unsigned int num_entries;
  unsigned int size;
  unsigned int hook_entry[5];
  unsigned int underflow[5];
  unsigned int num_counters;
  struct xt_counters* counters;
  char entrytable[XT_TABLE_SIZE];
};

struct ipt_table_desc {
  const char* name;
  struct ipt_getinfo info;
  struct ipt_replace replace;
};

static struct ipt_table_desc ipv4_tables[] = {
    {.name = "filter"}, {.name = "nat"},      {.name = "mangle"},
    {.name = "raw"},    {.name = "security"},
};

static struct ipt_table_desc ipv6_tables[] = {
    {.name = "filter"}, {.name = "nat"},      {.name = "mangle"},
    {.name = "raw"},    {.name = "security"},
};

#define IPT_BASE_CTL 64
#define IPT_SO_SET_REPLACE (IPT_BASE_CTL)
#define IPT_SO_GET_INFO (IPT_BASE_CTL)
#define IPT_SO_GET_ENTRIES (IPT_BASE_CTL + 1)

struct arpt_getinfo {
  char name[32];
  unsigned int valid_hooks;
  unsigned int hook_entry[3];
  unsigned int underflow[3];
  unsigned int num_entries;
  unsigned int size;
};

struct arpt_get_entries {
  char name[32];
  unsigned int size;
  void* entrytable[XT_TABLE_SIZE / sizeof(void*)];
};

struct arpt_replace {
  char name[32];
  unsigned int valid_hooks;
  unsigned int num_entries;
  unsigned int size;
  unsigned int hook_entry[3];
  unsigned int underflow[3];
  unsigned int num_counters;
  struct xt_counters* counters;
  char entrytable[XT_TABLE_SIZE];
};

struct arpt_table_desc {
  const char* name;
  struct arpt_getinfo info;
  struct arpt_replace replace;
};

static struct arpt_table_desc arpt_tables[] = {
    {.name = "filter"},
};

#define ARPT_BASE_CTL 96
#define ARPT_SO_SET_REPLACE (ARPT_BASE_CTL)
#define ARPT_SO_GET_INFO (ARPT_BASE_CTL)
#define ARPT_SO_GET_ENTRIES (ARPT_BASE_CTL + 1)

static void checkpoint_iptables(struct ipt_table_desc* tables, int num_tables,
                                int family, int level)
{
  struct ipt_get_entries entries;
  socklen_t optlen;
  int fd, i;

  fd = socket(family, SOCK_STREAM, IPPROTO_TCP);
  if (fd == -1)
    fail("socket(%d, SOCK_STREAM, IPPROTO_TCP)", family);
  for (i = 0; i < num_tables; i++) {
    struct ipt_table_desc* table = &tables[i];
    strcpy(table->info.name, table->name);
    strcpy(table->replace.name, table->name);
    optlen = sizeof(table->info);
    if (getsockopt(fd, level, IPT_SO_GET_INFO, &table->info, &optlen)) {
      switch (errno) {
      case EPERM:
      case ENOENT:
      case ENOPROTOOPT:
        continue;
      }
      fail("getsockopt(IPT_SO_GET_INFO)");
    }
    if (table->info.size > sizeof(table->replace.entrytable))
      fail("table size is too large: %u", table->info.size);
    if (table->info.num_entries > XT_MAX_ENTRIES)
      fail("too many counters: %u", table->info.num_entries);
    memset(&entries, 0, sizeof(entries));
    strcpy(entries.name, table->name);
    entries.size = table->info.size;
    optlen = sizeof(entries) - sizeof(entries.entrytable) + table->info.size;
    if (getsockopt(fd, level, IPT_SO_GET_ENTRIES, &entries, &optlen))
      fail("getsockopt(IPT_SO_GET_ENTRIES)");
    table->replace.valid_hooks = table->info.valid_hooks;
    table->replace.num_entries = table->info.num_entries;
    table->replace.size = table->info.size;
    memcpy(table->replace.hook_entry, table->info.hook_entry,
           sizeof(table->replace.hook_entry));
    memcpy(table->replace.underflow, table->info.underflow,
           sizeof(table->replace.underflow));
    memcpy(table->replace.entrytable, entries.entrytable, table->info.size);
  }
  close(fd);
}

static void reset_iptables(struct ipt_table_desc* tables, int num_tables,
                           int family, int level)
{
  struct xt_counters counters[XT_MAX_ENTRIES];
  struct ipt_get_entries entries;
  struct ipt_getinfo info;
  socklen_t optlen;
  int fd, i;

  fd = socket(family, SOCK_STREAM, IPPROTO_TCP);
  if (fd == -1)
    fail("socket(%d, SOCK_STREAM, IPPROTO_TCP)", family);
  for (i = 0; i < num_tables; i++) {
    struct ipt_table_desc* table = &tables[i];
    if (table->info.valid_hooks == 0)
      continue;
    memset(&info, 0, sizeof(info));
    strcpy(info.name, table->name);
    optlen = sizeof(info);
    if (getsockopt(fd, level, IPT_SO_GET_INFO, &info, &optlen))
      fail("getsockopt(IPT_SO_GET_INFO)");
    if (memcmp(&table->info, &info, sizeof(table->info)) == 0) {
      memset(&entries, 0, sizeof(entries));
      strcpy(entries.name, table->name);
      entries.size = table->info.size;
      optlen = sizeof(entries) - sizeof(entries.entrytable) + entries.size;
      if (getsockopt(fd, level, IPT_SO_GET_ENTRIES, &entries, &optlen))
        fail("getsockopt(IPT_SO_GET_ENTRIES)");
      if (memcmp(table->replace.entrytable, entries.entrytable,
                 table->info.size) == 0)
        continue;
    }
    table->replace.num_counters = info.num_entries;
    table->replace.counters = counters;
    optlen = sizeof(table->replace) - sizeof(table->replace.entrytable) +
             table->replace.size;
    if (setsockopt(fd, level, IPT_SO_SET_REPLACE, &table->replace, optlen))
      fail("setsockopt(IPT_SO_SET_REPLACE)");
  }
  close(fd);
}

static void checkpoint_arptables(void)
{
  struct arpt_get_entries entries;
  socklen_t optlen;
  unsigned i;
  int fd;

  fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
  if (fd == -1)
    fail("socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)");
  for (i = 0; i < sizeof(arpt_tables) / sizeof(arpt_tables[0]); i++) {
    struct arpt_table_desc* table = &arpt_tables[i];
    strcpy(table->info.name, table->name);
    strcpy(table->replace.name, table->name);
    optlen = sizeof(table->info);
    if (getsockopt(fd, SOL_IP, ARPT_SO_GET_INFO, &table->info, &optlen)) {
      switch (errno) {
      case EPERM:
      case ENOENT:
      case ENOPROTOOPT:
        continue;
      }
      fail("getsockopt(ARPT_SO_GET_INFO)");
    }
    if (table->info.size > sizeof(table->replace.entrytable))
      fail("table size is too large: %u", table->info.size);
    if (table->info.num_entries > XT_MAX_ENTRIES)
      fail("too many counters: %u", table->info.num_entries);
    memset(&entries, 0, sizeof(entries));
    strcpy(entries.name, table->name);
    entries.size = table->info.size;
    optlen = sizeof(entries) - sizeof(entries.entrytable) + table->info.size;
    if (getsockopt(fd, SOL_IP, ARPT_SO_GET_ENTRIES, &entries, &optlen))
      fail("getsockopt(ARPT_SO_GET_ENTRIES)");
    table->replace.valid_hooks = table->info.valid_hooks;
    table->replace.num_entries = table->info.num_entries;
    table->replace.size = table->info.size;
    memcpy(table->replace.hook_entry, table->info.hook_entry,
           sizeof(table->replace.hook_entry));
    memcpy(table->replace.underflow, table->info.underflow,
           sizeof(table->replace.underflow));
    memcpy(table->replace.entrytable, entries.entrytable, table->info.size);
  }
  close(fd);
}

static void reset_arptables()
{
  struct xt_counters counters[XT_MAX_ENTRIES];
  struct arpt_get_entries entries;
  struct arpt_getinfo info;
  socklen_t optlen;
  unsigned i;
  int fd;

  fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
  if (fd == -1)
    fail("socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)");
  for (i = 0; i < sizeof(arpt_tables) / sizeof(arpt_tables[0]); i++) {
    struct arpt_table_desc* table = &arpt_tables[i];
    if (table->info.valid_hooks == 0)
      continue;
    memset(&info, 0, sizeof(info));
    strcpy(info.name, table->name);
    optlen = sizeof(info);
    if (getsockopt(fd, SOL_IP, ARPT_SO_GET_INFO, &info, &optlen))
      fail("getsockopt(ARPT_SO_GET_INFO)");
    if (memcmp(&table->info, &info, sizeof(table->info)) == 0) {
      memset(&entries, 0, sizeof(entries));
      strcpy(entries.name, table->name);
      entries.size = table->info.size;
      optlen = sizeof(entries) - sizeof(entries.entrytable) + entries.size;
      if (getsockopt(fd, SOL_IP, ARPT_SO_GET_ENTRIES, &entries, &optlen))
        fail("getsockopt(ARPT_SO_GET_ENTRIES)");
      if (memcmp(table->replace.entrytable, entries.entrytable,
                 table->info.size) == 0)
        continue;
    }
    table->replace.num_counters = info.num_entries;
    table->replace.counters = counters;
    optlen = sizeof(table->replace) - sizeof(table->replace.entrytable) +
             table->replace.size;
    if (setsockopt(fd, SOL_IP, ARPT_SO_SET_REPLACE, &table->replace, optlen))
      fail("setsockopt(ARPT_SO_SET_REPLACE)");
  }
  close(fd);
}

static void checkpoint_net_namespace(void)
{
  checkpoint_arptables();
  checkpoint_iptables(ipv4_tables, sizeof(ipv4_tables) / sizeof(ipv4_tables[0]),
                      AF_INET, SOL_IP);
  checkpoint_iptables(ipv6_tables, sizeof(ipv6_tables) / sizeof(ipv6_tables[0]),
                      AF_INET6, SOL_IPV6);
}

static void reset_net_namespace(void)
{
  reset_arptables();
  reset_iptables(ipv4_tables, sizeof(ipv4_tables) / sizeof(ipv4_tables[0]),
                 AF_INET, SOL_IP);
  reset_iptables(ipv6_tables, sizeof(ipv6_tables) / sizeof(ipv6_tables[0]),
                 AF_INET6, SOL_IPV6);
}

static void test();

void loop()
{
  int iter;
  checkpoint_net_namespace();
  for (iter = 0;; iter++) {
    int pid = fork();
    if (pid < 0)
      fail("loop fork failed");
    if (pid == 0) {
      prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
      setpgrp();
      test();
      doexit(0);
    }
    int status = 0;
    uint64_t start = current_time_ms();
    for (;;) {
      int res = waitpid(-1, &status, __WALL | WNOHANG);
      if (res == pid)
        break;
      usleep(1000);
      if (current_time_ms() - start > 5 * 1000) {
        kill(-pid, SIGKILL);
        kill(pid, SIGKILL);
        while (waitpid(-1, &status, __WALL) != pid) {
        }
        break;
      }
    }
    reset_net_namespace();
  }
}

#ifndef __NR_mmap
#define __NR_mmap 192
#endif
#ifndef __NR_socket
#define __NR_socket 359
#endif
#ifndef __NR_connect
#define __NR_connect 362
#endif
#ifndef __NR_sendmsg
#define __NR_sendmsg 370
#endif
#undef __NR_mmap
#define __NR_mmap __NR_mmap2

long r[2];
void test()
{
  memset(r, -1, sizeof(r));
  syscall(__NR_mmap, 0x20000000, 0xfff000, 3, 0x32, -1, 0);
  r[0] = syscall(__NR_socket, 0xa, 2, 0);
  *(uint16_t*)0x20e6f000 = 0xa;
  *(uint16_t*)0x20e6f002 = htobe16(0x4e22);
  *(uint32_t*)0x20e6f004 = 0;
  *(uint8_t*)0x20e6f008 = 0;
  *(uint8_t*)0x20e6f009 = 0;
  *(uint8_t*)0x20e6f00a = 0;
  *(uint8_t*)0x20e6f00b = 0;
  *(uint8_t*)0x20e6f00c = 0;
  *(uint8_t*)0x20e6f00d = 0;
  *(uint8_t*)0x20e6f00e = 0;
  *(uint8_t*)0x20e6f00f = 0;
  *(uint8_t*)0x20e6f010 = 0;
  *(uint8_t*)0x20e6f011 = 0;
  *(uint8_t*)0x20e6f012 = -1;
  *(uint8_t*)0x20e6f013 = -1;
  *(uint8_t*)0x20e6f014 = 0xac;
  *(uint8_t*)0x20e6f015 = 0x14;
  *(uint8_t*)0x20e6f016 = 0;
  *(uint8_t*)0x20e6f017 = 0xaa;
  *(uint32_t*)0x20e6f018 = 1;
  syscall(__NR_connect, r[0], 0x20e6f000, 0x1c);
  *(uint16_t*)0x20d94fe4 = 0xa;
  *(uint16_t*)0x20d94fe6 = htobe16(0x4e20);
  *(uint32_t*)0x20d94fe8 = 4;
  *(uint8_t*)0x20d94fec = 0xfe;
  *(uint8_t*)0x20d94fed = 0x80;
  *(uint8_t*)0x20d94fee = 0;
  *(uint8_t*)0x20d94fef = 0;
  *(uint8_t*)0x20d94ff0 = 0;
  *(uint8_t*)0x20d94ff1 = 0;
  *(uint8_t*)0x20d94ff2 = 0;
  *(uint8_t*)0x20d94ff3 = 0;
  *(uint8_t*)0x20d94ff4 = 0;
  *(uint8_t*)0x20d94ff5 = 0;
  *(uint8_t*)0x20d94ff6 = 0;
  *(uint8_t*)0x20d94ff7 = 0;
  *(uint8_t*)0x20d94ff8 = 0;
  *(uint8_t*)0x20d94ff9 = 0;
  *(uint8_t*)0x20d94ffa = 0;
  *(uint8_t*)0x20d94ffb = 0xaa;
  *(uint32_t*)0x20d94ffc = 9;
  syscall(__NR_connect, r[0], 0x20d94fe4, 0x1c);
  r[1] = syscall(__NR_socket, 0x18, 1, 1);
  *(uint16_t*)0x205fafd2 = 0x18;
  *(uint32_t*)0x205fafd4 = 1;
  *(uint32_t*)0x205fafd8 = 0;
  *(uint32_t*)0x205fafdc = r[0];
  *(uint16_t*)0x205fafe0 = 2;
  *(uint16_t*)0x205fafe2 = htobe16(0x4e21);
  *(uint32_t*)0x205fafe4 = htobe32(0xe0000002);
  *(uint8_t*)0x205fafe8 = 0;
  *(uint8_t*)0x205fafe9 = 0;
  *(uint8_t*)0x205fafea = 0;
  *(uint8_t*)0x205fafeb = 0;
  *(uint8_t*)0x205fafec = 0;
  *(uint8_t*)0x205fafed = 0;
  *(uint8_t*)0x205fafee = 0;
  *(uint8_t*)0x205fafef = 0;
  *(uint32_t*)0x205faff0 = 4;
  *(uint32_t*)0x205faff4 = 0;
  *(uint32_t*)0x205faff8 = 2;
  *(uint32_t*)0x205faffc = 0;
  syscall(__NR_connect, r[1], 0x205fafd2, 0x2e);
  *(uint32_t*)0x20ab9000 = 0x20ea7ff8;
  *(uint32_t*)0x20ab9004 = 8;
  *(uint32_t*)0x20ab9008 = 0x20a2c000;
  *(uint32_t*)0x20ab900c = 1;
  *(uint32_t*)0x20ab9010 = 0x20496000;
  *(uint32_t*)0x20ab9014 = 0x54;
  *(uint32_t*)0x20ab9018 = 0x4081;
  *(uint16_t*)0x20ea7ff8 = 0;
  *(uint8_t*)0x20ea7ffa = 0;
  *(uint32_t*)0x20ea7ffc = 0x4e22;
  *(uint32_t*)0x20a2c000 = 0x20e7d000;
  *(uint32_t*)0x20a2c004 = 0;
  *(uint32_t*)0x20496000 = 0xc;
  *(uint32_t*)0x20496004 = 0x19f;
  *(uint32_t*)0x20496008 = 0x1f;
  *(uint32_t*)0x2049600c = 0xc;
  *(uint32_t*)0x20496010 = 0x108;
  *(uint32_t*)0x20496014 = 9;
  *(uint32_t*)0x20496018 = 0xc;
  *(uint32_t*)0x2049601c = 0x119;
  *(uint32_t*)0x20496020 = 4;
  *(uint32_t*)0x20496024 = 0xc;
  *(uint32_t*)0x20496028 = 0x101;
  *(uint32_t*)0x2049602c = 0x1000;
  *(uint32_t*)0x20496030 = 0xc;
  *(uint32_t*)0x20496034 = 0;
  *(uint32_t*)0x20496038 = 0x1ff;
  *(uint32_t*)0x2049603c = 0xc;
  *(uint32_t*)0x20496040 = 0xff;
  *(uint32_t*)0x20496044 = 0xffff;
  *(uint32_t*)0x20496048 = 0xc;
  *(uint32_t*)0x2049604c = 0x10e;
  *(uint32_t*)0x20496050 = 0xfffffffc;
  syscall(__NR_sendmsg, r[1], 0x20ab9000, 0x8090);
  *(uint8_t*)0x20f49030 = 0xaa;
  *(uint8_t*)0x20f49031 = 0xaa;
  *(uint8_t*)0x20f49032 = 0xaa;
  *(uint8_t*)0x20f49033 = 0xaa;
  *(uint8_t*)0x20f49034 = 0;
  *(uint8_t*)0x20f49035 = 0xaa;
  *(uint8_t*)0x20f49036 = 0;
  *(uint8_t*)0x20f49037 = 0;
  *(uint8_t*)0x20f49038 = 0;
  *(uint8_t*)0x20f49039 = 0;
  *(uint8_t*)0x20f4903a = 0;
  *(uint8_t*)0x20f4903b = 0;
  *(uint16_t*)0x20f4903c = htobe16(0x86dd);
  STORE_BY_BITMASK(uint8_t, 0x20f4903e, 0, 0, 4);
  STORE_BY_BITMASK(uint8_t, 0x20f4903e, 6, 4, 4);
  memcpy((void*)0x20f4903f, "\x00\x08\x07", 3);
  *(uint16_t*)0x20f49042 = htobe16(0x14);
  *(uint8_t*)0x20f49044 = 0;
  *(uint8_t*)0x20f49045 = 0;
  *(uint8_t*)0x20f49046 = 0xfe;
  *(uint8_t*)0x20f49047 = 0x80;
  *(uint8_t*)0x20f49048 = 0;
  *(uint8_t*)0x20f49049 = 0;
  *(uint8_t*)0x20f4904a = 0;
  *(uint8_t*)0x20f4904b = 0;
  *(uint8_t*)0x20f4904c = 0;
  *(uint8_t*)0x20f4904d = 0;
  *(uint8_t*)0x20f4904e = 0;
  *(uint8_t*)0x20f4904f = 0;
  *(uint8_t*)0x20f49050 = 0;
  *(uint8_t*)0x20f49051 = 0;
  *(uint8_t*)0x20f49052 = 0;
  *(uint8_t*)0x20f49053 = 0;
  *(uint8_t*)0x20f49054 = 0;
  *(uint8_t*)0x20f49055 = 0xbb;
  *(uint8_t*)0x20f49056 = -1;
  *(uint8_t*)0x20f49057 = 2;
  *(uint8_t*)0x20f49058 = 0;
  *(uint8_t*)0x20f49059 = 0;
  *(uint8_t*)0x20f4905a = 0;
  *(uint8_t*)0x20f4905b = 0;
  *(uint8_t*)0x20f4905c = 0;
  *(uint8_t*)0x20f4905d = 0;
  *(uint8_t*)0x20f4905e = 0;
  *(uint8_t*)0x20f4905f = 0;
  *(uint8_t*)0x20f49060 = 0;
  *(uint8_t*)0x20f49061 = 0;
  *(uint8_t*)0x20f49062 = 0;
  *(uint8_t*)0x20f49063 = 0;
  *(uint8_t*)0x20f49064 = 0;
  *(uint8_t*)0x20f49065 = 1;
  *(uint16_t*)0x20f49066 = 0;
  *(uint16_t*)0x20f49068 = 0;
  *(uint32_t*)0x20f4906a = 0x42424242;
  *(uint32_t*)0x20f4906e = 0x42424242;
  STORE_BY_BITMASK(uint8_t, 0x20f49072, 0, 0, 1);
  STORE_BY_BITMASK(uint8_t, 0x20f49072, 0, 1, 3);
  STORE_BY_BITMASK(uint8_t, 0x20f49072, 5, 4, 4);
  *(uint8_t*)0x20f49073 = 0;
  *(uint16_t*)0x20f49074 = htobe16(0);
  *(uint16_t*)0x20f49076 = 0;
  *(uint16_t*)0x20f49078 = htobe16(0);
  struct csum_inet csum_1;
  csum_inet_init(&csum_1);
  csum_inet_update(&csum_1, (const uint8_t*)0x20f49046, 16);
  csum_inet_update(&csum_1, (const uint8_t*)0x20f49056, 16);
  uint32_t csum_1_chunk_2 = 0x14000000;
  csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_2, 4);
  uint32_t csum_1_chunk_3 = 0x6000000;
  csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_3, 4);
  csum_inet_update(&csum_1, (const uint8_t*)0x20f49066, 20);
  *(uint16_t*)0x20f49076 = csum_inet_digest(&csum_1);
}

int main()
{
  for (;;) {
    loop();
  }
}