* util.c -- set of various support routines.

/*
* util.c -- set of various support routines.
*
* Copyright (c) 2001-2006, NLnet Labs. All rights reserved.
*
* See LICENSE for the license.
*
*/

#include "config.h"

#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_SCHED_H
#include <sched.h>
#endif /* HAVE_SCHED_H */
#ifdef HAVE_SYS_CPUSET_H
#include <sys/cpuset.h>
#endif /* HAVE_SYS_CPUSET_H */
#ifdef HAVE_SYSLOG_H
#include <syslog.h>
#endif /* HAVE_SYSLOG_H */
#include <unistd.h>
#ifdef HAVE_SYS_RANDOM_H
#include <sys/random.h>
#endif

#include "util.h"
#include "region-allocator.h"
#include "dname.h"
#include "namedb.h"
#include "rdata.h"
#include "zonec.h"
#include "nsd.h"

#ifdef USE_MMAP_ALLOC
#include <sys/mman.h>

#if defined(MAP_ANON) && !defined(MAP_ANONYMOUS)
#define MAP_ANONYMOUS MAP_ANON
#elif defined(MAP_ANONYMOUS) && !defined(MAP_ANON)
#define MAP_ANON MAP_ANONYMOUS
#endif

#endif /* USE_MMAP_ALLOC */

#ifndef NDEBUG
unsigned nsd_debug_facilities = 0xffff;
int nsd_debug_level = 0;
#endif

#define MSB_32 0x80000000

int verbosity = 0;

static const char *global_ident = NULL;
static log_function_type *current_log_function = log_file;
static FILE *current_log_file = NULL;
int log_time_asc = 1;

void
log_init(const char *ident)
{
global_ident = ident;
current_log_file = stderr;
}

void
log_open(int option, int facility, const char *filename)
{
#ifdef HAVE_SYSLOG_H
openlog(global_ident, option, facility);
#endif /* HAVE_SYSLOG_H */
if (filename) {
FILE *file = fopen(filename, "a");
if (!file) {
log_msg(LOG_ERR, "Cannot open %s for appending (%s), "
"logging to stderr",
filename, strerror(errno));
} else {
current_log_file = file;
}
}
}

void
log_reopen(const char *filename, uint8_t verbose)
{
if (filename) {
FILE *file;
if(strcmp(filename, "/dev/stdout")==0 || strcmp(filename, "/dev/stderr")==0)
return;
file = fopen(filename, "a");
if (!file) {
if (verbose)
VERBOSITY(2, (LOG_WARNING,
"Cannot reopen %s for appending (%s), "
"keeping old logfile",
filename, strerror(errno)));
} else {
if (current_log_file && current_log_file != stderr)
fclose(current_log_file);
current_log_file = file;
}
}
}

void
log_finalize(void)
{
#ifdef HAVE_SYSLOG_H
closelog();
#endif /* HAVE_SYSLOG_H */
if (current_log_file && current_log_file != stderr) {
fclose(current_log_file);
}
current_log_file = NULL;
}

static lookup_table_type log_priority_table[] = {
{ LOG_ERR, "error" },
{ LOG_WARNING, "warning" },
{ LOG_NOTICE, "notice" },
{ LOG_INFO, "info" },
{ 0, NULL }
};

void
log_file(int priority, const char *message)
{
size_t length;
lookup_table_type *priority_info;
const char *priority_text = "unknown";

assert(global_ident);
assert(current_log_file);

priority_info = lookup_by_id(log_priority_table, priority);
if (priority_info) {
priority_text = priority_info->name;
}

/* Bug #104, add time_t timestamp */
#if defined(HAVE_STRFTIME) && defined(HAVE_LOCALTIME_R)
if(log_time_asc) {
struct timeval tv;
char tmbuf[32];
tmbuf[0]=0;
tv.tv_usec = 0;
if(gettimeofday(&tv, NULL) == 0) {
struct tm tm;
time_t now = (time_t)tv.tv_sec;
strftime(tmbuf, sizeof(tmbuf), "%Y-%m-%d %H:%M:%S",
localtime_r(&now, &tm));
}
fprintf(current_log_file, "[%s.%3.3d] %s[%d]: %s: %s",
tmbuf, (int)tv.tv_usec/1000,
global_ident, (int) getpid(), priority_text, message);
} else
#endif /* have time functions */
fprintf(current_log_file, "[%d] %s[%d]: %s: %s",
(int)time(NULL), global_ident, (int) getpid(), priority_text, message);
length = strlen(message);
if (length == 0 || message[length - 1] != '\n') {
fprintf(current_log_file, "\n");
}
fflush(current_log_file);
}

void
log_syslog(int priority, const char *message)
{
#ifdef HAVE_SYSLOG_H
syslog(priority, "%s", message);
#endif /* !HAVE_SYSLOG_H */
log_file(priority, message);
}

void
log_only_syslog(int priority, const char *message)
{
#ifdef HAVE_SYSLOG_H
syslog(priority, "%s", message);
#else /* !HAVE_SYSLOG_H */
/* no syslog, use stderr */
log_file(priority, message);
#endif
}

void
log_set_log_function(log_function_type *log_function)
{
current_log_function = log_function;
}

void
log_msg(int priority, const char *format, ...)
{
va_list args;
va_start(args, format);
log_vmsg(priority, format, args);
va_end(args);
}

void
log_vmsg(int priority, const char *format, va_list args)
{
char message[MAXSYSLOGMSGLEN];
vsnprintf(message, sizeof(message), format, args);
current_log_function(priority, message);
}

void
set_bit(uint8_t bits[], size_t index)
{
/*
* The bits are counted from left to right, so bit #0 is the
* left most bit.
*/
bits[index / 8] |= (1 << (7 - index % 8));
}

void
clear_bit(uint8_t bits[], size_t index)
{
/*
* The bits are counted from left to right, so bit #0 is the
* left most bit.
*/
bits[index / 8] &= ~(1 << (7 - index % 8));
}

int
get_bit(uint8_t bits[], size_t index)
{
/*
* The bits are counted from left to right, so bit #0 is the
* left most bit.
*/
return bits[index / 8] & (1 << (7 - index % 8));
}

lookup_table_type *
lookup_by_name(lookup_table_type *table, const char *name)
{
while (table->name != NULL) {
if (strcasecmp(name, table->name) == 0)
return table;
table++;
}
return NULL;
}

lookup_table_type *
lookup_by_id(lookup_table_type *table, int id)
{
while (table->name != NULL) {
if (table->id == id)
return table;
table++;
}
return NULL;
}

char *
xstrdup(const char *src)
{
char *result = strdup(src);

if(!result) {
log_msg(LOG_ERR, "strdup failed: %s", strerror(errno));
exit(1);
}

return result;
}

void *
xalloc(size_t size)
{
void *result = malloc(size);

if (!result) {
log_msg(LOG_ERR, "malloc failed: %s", strerror(errno));
exit(1);
}
return result;
}

void *
xmallocarray(size_t num, size_t size)
{
void *result = reallocarray(NULL, num, size);

if (!result) {
log_msg(LOG_ERR, "reallocarray failed: %s", strerror(errno));
exit(1);
}
return result;
}

void *
xalloc_zero(size_t size)
{
void *result = calloc(1, size);
if (!result) {
log_msg(LOG_ERR, "calloc failed: %s", strerror(errno));
exit(1);
}
return result;
}

void *
xalloc_array_zero(size_t num, size_t size)
{
void *result = calloc(num, size);
if (!result) {
log_msg(LOG_ERR, "calloc failed: %s", strerror(errno));
exit(1);
}
return result;
}

void *
xrealloc(void *ptr, size_t size)
{
ptr = realloc(ptr, size);
if (!ptr) {
log_msg(LOG_ERR, "realloc failed: %s", strerror(errno));
exit(1);
}
return ptr;
}

#ifdef USE_MMAP_ALLOC

void *
mmap_alloc(size_t size)
{
void *base;

size += MMAP_ALLOC_HEADER_SIZE;
#ifdef HAVE_MMAP
base = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (base == MAP_FAILED) {
log_msg(LOG_ERR, "mmap failed: %s", strerror(errno));
exit(1);
}
#else /* !HAVE_MMAP */
log_msg(LOG_ERR, "mmap failed: don't have mmap");
exit(1);
#endif /* HAVE_MMAP */

*((size_t*) base) = size;
return (void*)((uintptr_t)base + MMAP_ALLOC_HEADER_SIZE);
}

void
mmap_free(void *ptr)
{
void *base;
size_t size;

if (!ptr) return;

base = (void*)((uintptr_t)ptr - MMAP_ALLOC_HEADER_SIZE);
size = *((size_t*) base);

#ifdef HAVE_MUNMAP
if (munmap(base, size) == -1) {
log_msg(LOG_ERR, "munmap failed: %s", strerror(errno));
exit(1);
}
#else /* !HAVE_MUNMAP */
log_msg(LOG_ERR, "munmap failed: don't have munmap");
exit(1);
#endif /* HAVE_MUNMAP */
}

#endif /* USE_MMAP_ALLOC */

int
write_data(FILE *file, const void *data, size_t size)
{
size_t result;

if (size == 0)
return 1;

result = fwrite(data, 1, size, file);

if (result == 0) {
log_msg(LOG_ERR, "write failed: %s", strerror(errno));
return 0;
} else if (result < size) {
log_msg(LOG_ERR, "short write (disk full?)");
return 0;
} else {
return 1;
}
}

int
write_socket(int s, const void *buf, size_t size)
{
const char* data = (const char*)buf;
size_t total_count = 0;

while (total_count < size) {
ssize_t count
= write(s, data + total_count, size - total_count);
if (count == -1) {
if (errno != EAGAIN && errno != EINTR) {
return 0;
} else {
continue;
}
}
total_count += count;
}
return 1;
}

void get_time(struct timespec* t)
{
struct timeval tv;
#ifdef HAVE_CLOCK_GETTIME
/* first try nanosecond precision */
if(clock_gettime(CLOCK_REALTIME, t)>=0) {
return; /* success */
}
log_msg(LOG_ERR, "clock_gettime: %s", strerror(errno));
#endif
/* try millisecond precision */
if(gettimeofday(&tv, NULL)>=0) {
t->tv_sec = tv.tv_sec;
t->tv_nsec = tv.tv_usec*1000;
return; /* success */
}
log_msg(LOG_ERR, "gettimeofday: %s", strerror(errno));
/* whole seconds precision */
t->tv_sec = time(0);
t->tv_nsec = 0;
}

int
timespec_compare(const struct timespec *left,
const struct timespec *right)
{
/* Compare seconds. */
if (left->tv_sec < right->tv_sec) {
return -1;
} else if (left->tv_sec > right->tv_sec) {
return 1;
} else {
/* Seconds are equal, compare nanoseconds. */
if (left->tv_nsec < right->tv_nsec) {
return -1;
} else if (left->tv_nsec > right->tv_nsec) {
return 1;
} else {
return 0;
}
}
}

/* One second is 1e9 nanoseconds. */
#define NANOSECONDS_PER_SECOND 1000000000L

void
timespec_add(struct timespec *left,
const struct timespec *right)
{
left->tv_sec += right->tv_sec;
left->tv_nsec += right->tv_nsec;
if (left->tv_nsec >= NANOSECONDS_PER_SECOND) {
/* Carry. */
++left->tv_sec;
left->tv_nsec -= NANOSECONDS_PER_SECOND;
}
}

void
timespec_subtract(struct timespec *left,
const struct timespec *right)
{
left->tv_sec -= right->tv_sec;
left->tv_nsec -= right->tv_nsec;
if (left->tv_nsec < 0L) {
/* Borrow. */
--left->tv_sec;
left->tv_nsec += NANOSECONDS_PER_SECOND;
}
}

uint32_t
strtoserial(const char* nptr, const char** endptr)
{
uint32_t i = 0;
uint32_t serial = 0;

for(*endptr = nptr; **endptr; (*endptr)++) {
switch (**endptr) {
case ' ':
case '\t':
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
if((i*10)/10 != i)
/* number too large, return i
* with *endptr != 0 as a failure*/
return i;
i *= 10;
i += (**endptr - '0');
break;
default:
return 0;
}
}
serial += i;
return serial;
}

uint32_t
strtottl(const char *nptr, const char **endptr)
{
uint32_t i = 0;
uint32_t seconds = 0;

for(*endptr = nptr; **endptr; (*endptr)++) {
switch (**endptr) {
case ' ':
case '\t':
break;
case 's':
case 'S':
seconds += i;
i = 0;
break;
case 'm':
case 'M':
seconds += i * 60;
i = 0;
break;
case 'h':
case 'H':
seconds += i * 60 * 60;
i = 0;
break;
case 'd':
case 'D':
seconds += i * 60 * 60 * 24;
i = 0;
break;
case 'w':
case 'W':
seconds += i * 60 * 60 * 24 * 7;
i = 0;
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
i *= 10;
i += (**endptr - '0');
break;
default:
seconds += i;
/**
* According to RFC2308, Section 8, the MSB
* (sign bit) should be set to zero.
* If we encounter a value larger than 2^31 -1,
* we fall back to the default TTL.
*/
if ((seconds & MSB_32)) {
seconds = DEFAULT_TTL;
}
return seconds;
}
}
seconds += i;
if ((seconds & MSB_32)) {
seconds = DEFAULT_TTL;
}
return seconds;
}

ssize_t
hex_ntop(uint8_t const *src, size_t srclength, char *target, size_t targsize)
{
static char hexdigits[] = {
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};
size_t i;

if (targsize < srclength * 2 + 1) {
return -1;
}

for (i = 0; i < srclength; ++i) {
*target++ = hexdigits[src[i] >> 4U];
*target++ = hexdigits[src[i] & 0xfU];
}
*target = '\0';
return 2 * srclength;
}

ssize_t
hex_pton(const char* src, uint8_t* target, size_t targsize)
{
uint8_t *t = target;
if(strlen(src) % 2 != 0 || strlen(src)/2 > targsize) {
return -1;
}
while(*src) {
if(!isxdigit((unsigned char)src[0]) ||
!isxdigit((unsigned char)src[1]))
return -1;
*t++ = hexdigit_to_int(src[0]) * 16 +
hexdigit_to_int(src[1]) ;
src += 2;
}
return t-target;
}

int
b32_ntop(uint8_t const *src, size_t srclength, char *target, size_t targsize)
{
static char b32[]="0123456789abcdefghijklmnopqrstuv";
char buf[9];
ssize_t len=0;

while(srclength > 0)
{
int t;
memset(buf,'\0',sizeof buf);

/* xxxxx000 00000000 00000000 00000000 00000000 */
buf[0]=b32[src[0] >> 3];

/* 00000xxx xx000000 00000000 00000000 00000000 */
t=(src[0]&7) << 2;
if(srclength > 1)
t+=src[1] >> 6;
buf[1]=b32[t];
if(srclength == 1)
break;

/* 00000000 00xxxxx0 00000000 00000000 00000000 */
buf[2]=b32[(src[1] >> 1)&0x1f];

/* 00000000 0000000x xxxx0000 00000000 00000000 */
t=(src[1]&1) << 4;
if(srclength > 2)
t+=src[2] >> 4;
buf[3]=b32[t];
if(srclength == 2)
break;

/* 00000000 00000000 0000xxxx x0000000 00000000 */
t=(src[2]&0xf) << 1;
if(srclength > 3)
t+=src[3] >> 7;
buf[4]=b32[t];
if(srclength == 3)
break;

/* 00000000 00000000 00000000 0xxxxx00 00000000 */
buf[5]=b32[(src[3] >> 2)&0x1f];

/* 00000000 00000000 00000000 000000xx xxx00000 */
t=(src[3]&3) << 3;
if(srclength > 4)
t+=src[4] >> 5;
buf[6]=b32[t];
if(srclength == 4)
break;

/* 00000000 00000000 00000000 00000000 000xxxxx */
buf[7]=b32[src[4]&0x1f];

if(targsize < 8)
return -1;

src += 5;
srclength -= 5;

memcpy(target,buf,8);
target += 8;
targsize -= 8;
len += 8;
}
if(srclength)
{
size_t tlen = strlcpy(target, buf, targsize);
if (tlen >= targsize)
return -1;
len += tlen;
}
else if(targsize < 1)
return -1;
else
*target='\0';
return len;
}

int
b32_pton(const char *src, uint8_t *target, size_t tsize)
{
char ch;
size_t p=0;

memset(target,'\0',tsize);
while((ch = *src++)) {
uint8_t d;
size_t b;
size_t n;

if(p+5 >= tsize*8)
return -1;

if(isspace((unsigned char)ch))
continue;

if(ch >= '0' && ch <= '9')
d=ch-'0';
else if(ch >= 'A' && ch <= 'V')
d=ch-'A'+10;
else if(ch >= 'a' && ch <= 'v')
d=ch-'a'+10;
else
return -1;

b=7-p%8;
n=p/8;

if(b >= 4)
target[n]|=d << (b-4);
else {
target[n]|=d >> (4-b);
target[n+1]|=d << (b+4);
}
p+=5;
}
return (p+7)/8;
}

void
strip_string(char *str)
{
char *start = str;
char *end = str + strlen(str) - 1;

while (isspace((unsigned char)*start))
++start;
if (start > end) {
/* Completely blank. */
str[0] = '\0';
} else {
while (isspace((unsigned char)*end))
--end;
*++end = '\0';

if (str != start)
memmove(str, start, end - start + 1);
}
}

int
hexdigit_to_int(char ch)
{
switch (ch) {
case '0': return 0;
case '1': return 1;
case '2': return 2;
case '3': return 3;
case '4': return 4;
case '5': return 5;
case '6': return 6;
case '7': return 7;
case '8': return 8;
case '9': return 9;
case 'a': case 'A': return 10;
case 'b': case 'B': return 11;
case 'c': case 'C': return 12;
case 'd': case 'D': return 13;
case 'e': case 'E': return 14;
case 'f': case 'F': return 15;
default:
abort();
}
}

/* Number of days per month (except for February in leap years). */
static const int mdays[] = {
31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};

static int
is_leap_year(int year)
{
return year % 4 == 0 && (year % 100 != 0 || year % 400 == 0);
}

static int
leap_days(int y1, int y2)
{
--y1;
--y2;
return (y2/4 - y1/4) - (y2/100 - y1/100) + (y2/400 - y1/400);
}

/*
* Code adapted from Python 2.4.1 sources (Lib/calendar.py).
*/
time_t
mktime_from_utc(const struct tm *tm)
{
int year = 1900 + tm->tm_year;
time_t days = 365 * (year - 1970) + leap_days(1970, year);
time_t hours;
time_t minutes;
time_t seconds;
int i;

for (i = 0; i < tm->tm_mon; ++i) {
days += mdays[i];
}
if (tm->tm_mon > 1 && is_leap_year(year)) {
++days;
}
days += tm->tm_mday - 1;

hours = days * 24 + tm->tm_hour;
minutes = hours * 60 + tm->tm_min;
seconds = minutes * 60 + tm->tm_sec;

return seconds;
}

/* code to calculate CRC. Lifted from BSD 4.4 crc.c in cksum(1). BSD license.
http://www.tsfr.org/~orc/Code/bsd/bsd-current/cksum/crc.c.
or http://gobsd.com/code/freebsd/usr.bin/cksum/crc.c
The polynomial is 0x04c11db7L. */
static uint32_t crctab[] = {
0x0,
0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b,
0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6,
0x2b4bcb61, 0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9, 0x5f15adac,
0x5bd4b01b, 0x569796c2, 0x52568b75, 0x6a1936c8, 0x6ed82b7f,
0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3, 0x709f7b7a,
0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58,
0xbaea46ef, 0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033,
0xa4ad16ea, 0xa06c0b5d, 0xd4326d90, 0xd0f37027, 0xddb056fe,
0xd9714b49, 0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1, 0xe13ef6f4,
0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0,
0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5,
0x2ac12072, 0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca, 0x7897ab07,
0x7c56b6b0, 0x71159069, 0x75d48dde, 0x6b93dddb, 0x6f52c06c,
0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1,
0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b,
0xbb60adfc, 0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698,
0x832f1041, 0x87ee0df6, 0x99a95df3, 0x9d684044, 0x902b669d,
0x94ea7b2a, 0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2, 0xc6bcf05f,
0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34,
0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80,
0x644fc637, 0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f, 0x5c007b8a,
0x58c1663d, 0x558240e4, 0x51435d53, 0x251d3b9e, 0x21dc2629,
0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5, 0x3f9b762c,
0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e,
0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65,
0xeba91bbc, 0xef68060b, 0xd727bbb6, 0xd3e6a601, 0xdea580d8,
0xda649d6f, 0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7, 0xae3afba2,
0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71,
0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74,
0x857130c3, 0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c, 0x7b827d21,
0x7f436096, 0x7200464f, 0x76c15bf8, 0x68860bfd, 0x6c47164a,
0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e, 0x18197087,
0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d,
0x2056cd3a, 0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce,
0xcc2b1d17, 0xc8ea00a0, 0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb,
0xdbee767c, 0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4, 0x89b8fd09,
0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662,
0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf,
0xa2f33668, 0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
};

#define COMPUTE(var, ch) (var) = (var) << 8 ^ crctab[(var) >> 24 ^ (ch)]

uint32_t
compute_crc(uint32_t crc, uint8_t* data, size_t len)
{
size_t i;
for(i=0; i<len; ++i)
COMPUTE(crc, data[i]);
return crc;
}

int
write_data_crc(FILE *file, const void *data, size_t size, uint32_t* crc)
{
int ret = write_data(file, data, size);
*crc = compute_crc(*crc, (uint8_t*)data, size);
return ret;
}

#define SERIAL_BITS 32
int
compare_serial(uint32_t a, uint32_t b)
{
const uint32_t cutoff = ((uint32_t) 1 << (SERIAL_BITS - 1));

if (a == b) {
return 0;
} else if ((a < b && b - a < cutoff) || (a > b && a - b > cutoff)) {
return -1;
} else {
return 1;
}
}

uint16_t
qid_generate(void)
{
#ifdef HAVE_GETRANDOM
uint16_t r;
if(getrandom(&r, sizeof(r), 0) == -1) {
log_msg(LOG_ERR, "getrandom failed: %s", strerror(errno));
exit(1);
}
return r;
#elif defined(HAVE_ARC4RANDOM)
/* arc4random_uniform not needed because range is a power of 2 */
return (uint16_t) arc4random();
#else
return (uint16_t) random();
#endif
}

int
random_generate(int max)
{
#ifdef HAVE_GETRANDOM
int r;
if(getrandom(&r, sizeof(r), 0) == -1) {
log_msg(LOG_ERR, "getrandom failed: %s", strerror(errno));
exit(1);
}
return (int)(((unsigned)r)%max);
#elif defined(HAVE_ARC4RANDOM_UNIFORM)
return (int) arc4random_uniform(max);
#elif defined(HAVE_ARC4RANDOM)
return (int) (arc4random() % max);
#else
return (int) ((unsigned)random() % max);
#endif
}

void
cleanup_region(void *data)
{
region_type *region = (region_type *) data;
region_destroy(region);
}

struct state_pretty_rr*
create_pretty_rr(struct region* region)
{
struct state_pretty_rr* state = (struct state_pretty_rr*)
region_alloc(region, sizeof(struct state_pretty_rr));
state->previous_owner_region = region_create(xalloc, free);
state->previous_owner = NULL;
state->previous_owner_origin = NULL;
region_add_cleanup(region, cleanup_region,
state->previous_owner_region);
return state;
}

static void
set_previous_owner(struct state_pretty_rr *state, const dname_type *dname)
{
region_free_all(state->previous_owner_region);
state->previous_owner = dname_copy(state->previous_owner_region, dname);
state->previous_owner_origin = dname_origin(
state->previous_owner_region, state->previous_owner);
}

int
print_rr(FILE *out,
struct state_pretty_rr *state,
rr_type *record,
region_type* rr_region,
buffer_type* output)
{
rrtype_descriptor_type *descriptor
= rrtype_descriptor_by_type(record->type);
int result;
const dname_type *owner = domain_dname(record->owner);
buffer_clear(output);
if (state) {
if (!state->previous_owner
|| dname_compare(state->previous_owner, owner) != 0) {
const dname_type *owner_origin
= dname_origin(rr_region, owner);
int origin_changed = (!state->previous_owner_origin
|| dname_compare(state->previous_owner_origin,
owner_origin) != 0);
if (origin_changed) {
buffer_printf(output, "$ORIGIN %s\n",
dname_to_string(owner_origin, NULL));
}

set_previous_owner(state, owner);
buffer_printf(output, "%s",
dname_to_string(owner,
state->previous_owner_origin));
region_free_all(rr_region);
}
} else {
buffer_printf(output, "%s", dname_to_string(owner, NULL));
}

buffer_printf(output, "\t%lu\t%s\t%s",
(unsigned long) record->ttl,
rrclass_to_string(record->klass),
rrtype_to_string(record->type));

result = print_rdata(output, descriptor, record);
if (!result) {
/*
* Some RDATA failed to print, so print the record's
* RDATA in unknown format.
*/
result = rdata_atoms_to_unknown_string(output,
descriptor, record->rdata_count, record->rdatas);
}

if (result) {
buffer_printf(output, "\n");
buffer_flip(output);
result = write_data(out, buffer_current(output),
buffer_remaining(output));
}
return result;
}

const char*
rcode2str(int rc)
{
switch(rc) {
case RCODE_OK:
return "NO ERROR";
case RCODE_FORMAT:
return "FORMAT ERROR";
case RCODE_SERVFAIL:
return "SERVFAIL";
case RCODE_NXDOMAIN:
return "NAME ERROR";
case RCODE_IMPL:
return "NOT IMPL";
case RCODE_REFUSE:
return "REFUSED";
case RCODE_YXDOMAIN:
return "YXDOMAIN";
case RCODE_YXRRSET:
return "YXRRSET";
case RCODE_NXRRSET:
return "NXRRSET";
case RCODE_NOTAUTH:
return "SERVER NOT AUTHORITATIVE FOR ZONE";
case RCODE_NOTZONE:
/* Name not contained in zone */
return "NOTZONE";
default:
return "UNKNOWN ERROR";
}
return NULL; /* ENOREACH */
}

void
addr2str(
#ifdef INET6
struct sockaddr_storage *addr
#else
struct sockaddr_in *addr
#endif
, char* str, size_t len)
{
#ifdef INET6
if (addr->ss_family == AF_INET6) {
if (!inet_ntop(AF_INET6,
&((struct sockaddr_in6 *)addr)->sin6_addr, str, len))
strlcpy(str, "[unknown ip6, inet_ntop failed]", len);
return;
}
#endif
if (!inet_ntop(AF_INET, &((struct sockaddr_in *)addr)->sin_addr,
str, len))
strlcpy(str, "[unknown ip4, inet_ntop failed]", len);
}

void
addrport2str(
#ifdef INET6
struct sockaddr_storage *addr
#else
struct sockaddr_in *addr
#endif
, char* str, size_t len)
{
char ip[256];
#ifdef INET6
if (addr->ss_family == AF_INET6) {
if (!inet_ntop(AF_INET6,
&((struct sockaddr_in6 *)addr)->sin6_addr, ip, sizeof(ip)))
strlcpy(ip, "[unknown ip6, inet_ntop failed]", sizeof(ip));
/* append port number */
snprintf(str, len, "%s@%u", ip,
(unsigned)ntohs(((struct sockaddr_in6 *)addr)->sin6_port));
return;
} else
#endif
if (!inet_ntop(AF_INET, &((struct sockaddr_in *)addr)->sin_addr,
ip, sizeof(ip)))
strlcpy(ip, "[unknown ip4, inet_ntop failed]", sizeof(ip));
/* append port number */
snprintf(str, len, "%s@%u", ip,
(unsigned)ntohs(((struct sockaddr_in *)addr)->sin_port));
}

void
append_trailing_slash(const char** dirname, region_type* region)
{
int l = strlen(*dirname);
if (l>0 && (*dirname)[l-1] != '/' && l < 0xffffff) {
char *dirname_slash = region_alloc(region, l+2);
memcpy(dirname_slash, *dirname, l+1);
strlcat(dirname_slash, "/", l+2);
/* old dirname is leaked, this is only used for chroot, once */
*dirname = dirname_slash;
}
}

int
file_inside_chroot(const char* fname, const char* chr)
{
/* true if filename starts with chroot or is not absolute */
return ((fname && fname[0] && strncmp(fname, chr, strlen(chr)) == 0) ||
(fname && fname[0] != '/'));
}

/*
* Something went wrong, give error messages and exit.
*/
void
error(const char *format, ...)
{
va_list args;
va_start(args, format);
log_vmsg(LOG_ERR, format, args);
va_end(args);
exit(1);
}

#ifdef HAVE_CPUSET_T
#if defined(HAVE_SYSCONF) && defined(_SC_NPROCESSORS_CONF)
/* exists on Linux and FreeBSD */
int number_of_cpus(void)
{
return (int)sysconf(_SC_NPROCESSORS_CONF);
}
#else
int number_of_cpus(void)
{
return -1;
}
#endif
#ifdef __gnu_hurd__
/* HURD has no sched_setaffinity implementation, but links an always fail,
* with a linker error, we print an error when it is used */
int set_cpu_affinity(cpuset_t *ATTR_UNUSED(set))
{
log_err("sched_setaffinity: not available on this system");
return -1;
}
#elif defined(HAVE_SCHED_SETAFFINITY)
/* Linux */
int set_cpu_affinity(cpuset_t *set)
{
assert(set != NULL);
return sched_setaffinity(getpid(), sizeof(*set), set);
}
#else
/* FreeBSD */
int set_cpu_affinity(cpuset_t *set)
{
assert(set != NULL);
return cpuset_setaffinity(
CPU_LEVEL_WHICH, CPU_WHICH_PID, -1, sizeof(*set), set);
}
#endif
#endif /* HAVE_CPUSET_T */

void add_cookie_secret(struct nsd* nsd, uint8_t* secret)
{
/* New cookie secret becomes the staging secret (position 1)
* unless there is no active cookie yet, then it becomes the active
* secret. If the NSD_COOKIE_HISTORY_SIZE > 2 then all staging cookies
* are moved one position down.
*/
if(nsd->cookie_count == 0) {
memcpy( nsd->cookie_secrets->cookie_secret
, secret, NSD_COOKIE_SECRET_SIZE);
nsd->cookie_count = 1;
explicit_bzero(secret, NSD_COOKIE_SECRET_SIZE);
return;
}
#if NSD_COOKIE_HISTORY_SIZE > 2
memmove( &nsd->cookie_secrets[2], &nsd->cookie_secrets[1]
, sizeof(struct cookie_secret) * (NSD_COOKIE_HISTORY_SIZE - 2));
#endif
memcpy( nsd->cookie_secrets[1].cookie_secret
, secret, NSD_COOKIE_SECRET_SIZE);
nsd->cookie_count = nsd->cookie_count < NSD_COOKIE_HISTORY_SIZE
? nsd->cookie_count + 1 : NSD_COOKIE_HISTORY_SIZE;
explicit_bzero(secret, NSD_COOKIE_SECRET_SIZE);
}

void activate_cookie_secret(struct nsd* nsd)
{
uint8_t active_secret[NSD_COOKIE_SECRET_SIZE];
/* The staging secret becomes the active secret.
* The active secret becomes a staging secret.
* If the NSD_COOKIE_HISTORY_SIZE > 2 then all staging secrets are moved
* one position up and the previously active secret becomes the last
* staging secret.
*/
if(nsd->cookie_count < 2)
return;
memcpy( active_secret, nsd->cookie_secrets[0].cookie_secret
, NSD_COOKIE_SECRET_SIZE);
memmove( &nsd->cookie_secrets[0], &nsd->cookie_secrets[1]
, sizeof(struct cookie_secret) * (NSD_COOKIE_HISTORY_SIZE - 1));
memcpy( nsd->cookie_secrets[nsd->cookie_count - 1].cookie_secret
, active_secret, NSD_COOKIE_SECRET_SIZE);
explicit_bzero(active_secret, NSD_COOKIE_SECRET_SIZE);
}

void drop_cookie_secret(struct nsd* nsd)
{
/* Drops a staging cookie secret. If there are more than one, it will
* drop the last staging secret. */
if(nsd->cookie_count < 2)
return;
explicit_bzero( nsd->cookie_secrets[nsd->cookie_count - 1].cookie_secret
, NSD_COOKIE_SECRET_SIZE);
nsd->cookie_count -= 1;
}