/* Create a socket connected to a name. */
int
__nscd_open_socket (const char *key, size_t keylen, request_type type,
void *response, size_t responselen)
{
int saved_errno = errno;
int sock = open_socket ();
if (sock >= 0)
{
request_header req;
req.version = NSCD_VERSION;
req.type = type;
req.key_len = keylen;
struct iovec vec[2];
vec[0].iov_base = &req;
vec[0].iov_len = sizeof (request_header);
vec[1].iov_base = (void *) key;
vec[1].iov_len = keylen;
ssize_t nbytes = TEMP_FAILURE_RETRY (__writev (sock, vec, 2));
if (nbytes == (ssize_t) (sizeof (request_header) + keylen)
/* Wait for data. */
&& wait_on_socket (sock) > 0)
{
nbytes = TEMP_FAILURE_RETRY (__read (sock, response, responselen));
if (nbytes == (ssize_t) responselen)
return sock;
}
close_not_cancel_no_status (sock);
}
__set_errno (saved_errno);
return -1;
}
static bool
writev_for_fatal (int fd, const struct iovec *iov, size_t niov, size_t total)
{
return TEMP_FAILURE_RETRY (__writev (fd, iov, niov)) == total;
}
void
__vsyslog_chk(int pri, int flag, const char *fmt, va_list ap)
{
struct tm now_tm;
time_t now;
int fd;
FILE *f;
char *buf = 0;
size_t bufsize = 0;
size_t msgoff;
#ifndef NO_SIGPIPE
struct sigaction action, oldaction;
int sigpipe;
#endif
int saved_errno = errno;
char failbuf[3 * sizeof (pid_t) + sizeof "out of memory []"];
#define INTERNALLOG LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID
/* Check for invalid bits. */
if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) {
syslog(INTERNALLOG,
"syslog: unknown facility/priority: %x", pri);
pri &= LOG_PRIMASK|LOG_FACMASK;
}
/* Check priority against setlogmask values. */
if ((LOG_MASK (LOG_PRI (pri)) & LogMask) == 0)
return;
/* Set default facility if none specified. */
if ((pri & LOG_FACMASK) == 0)
pri |= LogFacility;
/* Build the message in a memory-buffer stream. */
f = __open_memstream (&buf, &bufsize);
if (f == NULL)
{
/* We cannot get a stream. There is not much we can do but
emitting an error messages. */
char numbuf[3 * sizeof (pid_t)];
char *nump;
char *endp = __stpcpy (failbuf, "out of memory [");
pid_t pid = __getpid ();
nump = numbuf + sizeof (numbuf);
/* The PID can never be zero. */
do
*--nump = '0' + pid % 10;
while ((pid /= 10) != 0);
endp = __mempcpy (endp, nump, (numbuf + sizeof (numbuf)) - nump);
*endp++ = ']';
*endp = '\0';
buf = failbuf;
bufsize = endp - failbuf;
msgoff = 0;
}
else
{
__fsetlocking (f, FSETLOCKING_BYCALLER);
fprintf (f, "<%d>", pri);
(void) time (&now);
f->_IO_write_ptr += __strftime_l (f->_IO_write_ptr,
f->_IO_write_end
- f->_IO_write_ptr,
"%h %e %T ",
__localtime_r (&now, &now_tm),
_nl_C_locobj_ptr);
msgoff = ftell (f);
if (LogTag == NULL)
LogTag = __progname;
if (LogTag != NULL)
__fputs_unlocked (LogTag, f);
if (LogStat & LOG_PID)
fprintf (f, "[%d]", (int) __getpid ());
if (LogTag != NULL)
{
putc_unlocked (':', f);
putc_unlocked (' ', f);
}
/* Restore errno for %m format. */
__set_errno (saved_errno);
/* We have the header. Print the user's format into the
buffer. */
if (flag == -1)
vfprintf (f, fmt, ap);
else
__vfprintf_chk (f, flag, fmt, ap);
/* Close the memory stream; this will finalize the data
into a malloc'd buffer in BUF. */
fclose (f);
}
/* Output to stderr if requested. */
if (LogStat & LOG_PERROR) {
struct iovec iov[2];
struct iovec *v = iov;
v->iov_base = buf + msgoff;
v->iov_len = bufsize - msgoff;
/* Append a newline if necessary. */
if (buf[bufsize - 1] != '\n')
{
++v;
v->iov_base = (char *) "\n";
v->iov_len = 1;
}
__libc_cleanup_push (free, buf == failbuf ? NULL : buf);
/* writev is a cancellation point. */
(void)__writev(STDERR_FILENO, iov, v - iov + 1);
__libc_cleanup_pop (0);
}
/* Prepare for multiple users. We have to take care: open and
write are cancellation points. */
struct cleanup_arg clarg;
clarg.buf = buf;
clarg.oldaction = NULL;
__libc_cleanup_push (cancel_handler, &clarg);
__libc_lock_lock (syslog_lock);
#ifndef NO_SIGPIPE
/* Prepare for a broken connection. */
memset (&action, 0, sizeof (action));
action.sa_handler = sigpipe_handler;
sigemptyset (&action.sa_mask);
sigpipe = __sigaction (SIGPIPE, &action, &oldaction);
if (sigpipe == 0)
clarg.oldaction = &oldaction;
#endif
/* Get connected, output the message to the local logger. */
if (!connected)
openlog_internal(LogTag, LogStat | LOG_NDELAY, 0);
/* If we have a SOCK_STREAM connection, also send ASCII NUL as
a record terminator. */
if (LogType == SOCK_STREAM)
++bufsize;
if (!connected || __send(LogFile, buf, bufsize, send_flags) < 0)
{
if (connected)
{
/* Try to reopen the syslog connection. Maybe it went
down. */
closelog_internal ();
openlog_internal(LogTag, LogStat | LOG_NDELAY, 0);
}
if (!connected || __send(LogFile, buf, bufsize, send_flags) < 0)
{
closelog_internal (); /* attempt re-open next time */
/*
* Output the message to the console; don't worry
* about blocking, if console blocks everything will.
* Make sure the error reported is the one from the
* syslogd failure.
*/
if (LogStat & LOG_CONS &&
(fd = __open(_PATH_CONSOLE, O_WRONLY|O_NOCTTY, 0)) >= 0)
{
__dprintf (fd, "%s\r\n", buf + msgoff);
(void)__close(fd);
}
}
}
#ifndef NO_SIGPIPE
if (sigpipe == 0)
__sigaction (SIGPIPE, &oldaction, (struct sigaction *) NULL);
#endif
/* End of critical section. */
__libc_cleanup_pop (0);
__libc_lock_unlock (syslog_lock);
if (buf != failbuf)
free (buf);
}
/* Try to get a file descriptor for the shared meory segment
containing the database. */
static struct mapped_database *
get_mapping (request_type type, const char *key,
struct mapped_database **mappedp)
{
struct mapped_database *result = NO_MAPPING;
#ifdef SCM_RIGHTS
const size_t keylen = strlen (key) + 1;
char resdata[keylen];
int saved_errno = errno;
int mapfd = -1;
/* Send the request. */
struct iovec iov[2];
request_header req;
int sock = open_socket ();
if (sock < 0)
goto out;
req.version = NSCD_VERSION;
req.type = type;
req.key_len = keylen;
iov[0].iov_base = &req;
iov[0].iov_len = sizeof (req);
iov[1].iov_base = (void *) key;
iov[1].iov_len = keylen;
if (__builtin_expect (TEMP_FAILURE_RETRY (__writev (sock, iov, 2))
!= iov[0].iov_len + iov[1].iov_len, 0))
/* We cannot even write the request. */
goto out_close2;
/* Room for the data sent along with the file descriptor. We expect
the key name back. */
iov[0].iov_base = resdata;
iov[0].iov_len = keylen;
union
{
struct cmsghdr hdr;
char bytes[CMSG_SPACE (sizeof (int))];
} buf;
struct msghdr msg = { .msg_iov = iov, .msg_iovlen = 1,
.msg_control = buf.bytes,
.msg_controllen = sizeof (buf) };
struct cmsghdr *cmsg = CMSG_FIRSTHDR (&msg);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
cmsg->cmsg_len = CMSG_LEN (sizeof (int));
/* This access is well-aligned since BUF is correctly aligned for an
int and CMSG_DATA preserves this alignment. */
*(int *) CMSG_DATA (cmsg) = -1;
msg.msg_controllen = cmsg->cmsg_len;
if (wait_on_socket (sock) <= 0)
goto out_close2;
# ifndef MSG_NOSIGNAL
# define MSG_NOSIGNAL 0
# endif
if (__builtin_expect (TEMP_FAILURE_RETRY (__recvmsg (sock, &msg,
MSG_NOSIGNAL))
!= keylen, 0))
goto out_close2;
mapfd = *(int *) CMSG_DATA (cmsg);
if (__builtin_expect (CMSG_FIRSTHDR (&msg)->cmsg_len
!= CMSG_LEN (sizeof (int)), 0))
goto out_close;
struct stat64 st;
if (__builtin_expect (strcmp (resdata, key) != 0, 0)
|| __builtin_expect (fstat64 (mapfd, &st) != 0, 0)
|| __builtin_expect (st.st_size < sizeof (struct database_pers_head), 0))
goto out_close;
struct database_pers_head head;
if (__builtin_expect (TEMP_FAILURE_RETRY (__pread (mapfd, &head,
sizeof (head), 0))
!= sizeof (head), 0))
goto out_close;
if (__builtin_expect (head.version != DB_VERSION, 0)
|| __builtin_expect (head.header_size != sizeof (head), 0)
/* This really should not happen but who knows, maybe the update
thread got stuck. */
|| __builtin_expect (! head.nscd_certainly_running
&& head.timestamp + MAPPING_TIMEOUT < time (NULL),
0))
goto out_close;
size_t size = (sizeof (head) + roundup (head.module * sizeof (ref_t), ALIGN)
+ head.data_size);
if (__builtin_expect (st.st_size < size, 0))
goto out_close;
/* The file is large enough, map it now. */
void *mapping = __mmap (NULL, size, PROT_READ, MAP_SHARED, mapfd, 0);
if (__builtin_expect (mapping != MAP_FAILED, 1))
{
/* Allocate a record for the mapping. */
struct mapped_database *newp = malloc (sizeof (*newp));
if (newp == NULL)
{
/* Ugh, after all we went through the memory allocation failed. */
__munmap (mapping, size);
goto out_close;
}
newp->head = mapping;
newp->data = ((char *) mapping + head.header_size
+ roundup (head.module * sizeof (ref_t), ALIGN));
newp->mapsize = size;
/* Set counter to 1 to show it is usable. */
newp->counter = 1;
result = newp;
}
out_close:
__close (mapfd);
out_close2:
__close (sock);
out:
__set_errno (saved_errno);
#endif /* SCM_RIGHTS */
struct mapped_database *oldval = *mappedp;
*mappedp = result;
if (oldval != NULL && atomic_decrement_val (&oldval->counter) == 0)
__nscd_unmap (oldval);
return result;
}
struct mapped_database *
__nscd_get_map_ref (request_type type, const char *name,
struct locked_map_ptr *mapptr, int *gc_cyclep)
{
struct mapped_database *cur = mapptr->mapped;
if (cur == NO_MAPPING)
return cur;
int cnt = 0;
while (atomic_compare_and_exchange_val_acq (&mapptr->lock, 1, 0) != 0)
{
// XXX Best number of rounds?
if (++cnt > 5)
return NO_MAPPING;
atomic_delay ();
}
cur = mapptr->mapped;
if (__builtin_expect (cur != NO_MAPPING, 1))
{
/* If not mapped or timestamp not updated, request new map. */
if (cur == NULL
|| (cur->head->nscd_certainly_running == 0
&& cur->head->timestamp + MAPPING_TIMEOUT < time (NULL)))
cur = get_mapping (type, name, &mapptr->mapped);
if (__builtin_expect (cur != NO_MAPPING, 1))
{
if (__builtin_expect (((*gc_cyclep = cur->head->gc_cycle) & 1) != 0,
0))
cur = NO_MAPPING;
else
atomic_increment (&cur->counter);
}
}
mapptr->lock = 0;
return cur;
}
const struct datahead *
__nscd_cache_search (request_type type, const char *key, size_t keylen,
const struct mapped_database *mapped)
{
unsigned long int hash = __nis_hash (key, keylen) % mapped->head->module;
ref_t work = mapped->head->array[hash];
while (work != ENDREF)
{
struct hashentry *here = (struct hashentry *) (mapped->data + work);
if (type == here->type && keylen == here->len
&& memcmp (key, mapped->data + here->key, keylen) == 0)
{
/* We found the entry. Increment the appropriate counter. */
const struct datahead *dh
= (struct datahead *) (mapped->data + here->packet);
/* See whether we must ignore the entry or whether something
is wrong because garbage collection is in progress. */
if (dh->usable && ((char *) dh + dh->allocsize
<= (char *) mapped->head + mapped->mapsize))
return dh;
}
work = here->next;
}
return NULL;
}
void
__backtrace_symbols_fd (void *const *array, int size, int fd)
{
struct iovec iov[9];
int cnt;
for (cnt = 0; cnt < size; ++cnt)
{
char buf[WORD_WIDTH];
char buf2[WORD_WIDTH];
Dl_info info;
struct link_map *map;
size_t last = 0;
if (_dl_addr (array[cnt], &info, &map, NULL)
&& info.dli_fname != NULL && info.dli_fname[0] != '\0')
{
/* Name of the file. */
iov[0].iov_base = (void *) info.dli_fname;
iov[0].iov_len = strlen (info.dli_fname);
last = 1;
if (info.dli_sname != NULL || map->l_addr != 0)
{
size_t diff;
iov[last].iov_base = (void *) "(";
iov[last].iov_len = 1;
++last;
if (info.dli_sname != NULL)
{
/* We have a symbol name. */
iov[last].iov_base = (void *) info.dli_sname;
iov[last].iov_len = strlen (info.dli_sname);
++last;
}
else
/* We have no symbol, so describe it as relative to the file.
The load bias is more useful to the user than the load
address. The use of these addresses is to calculate an
address in the ELF file, so its prelinked bias is not
something we want to subtract out. */
info.dli_saddr = (void *) map->l_addr;
if (array[cnt] >= (void *) info.dli_saddr)
{
iov[last].iov_base = (void *) "+0x";
diff = array[cnt] - info.dli_saddr;
}
else
{
iov[last].iov_base = (void *) "-0x";
diff = info.dli_saddr - array[cnt];
}
iov[last].iov_len = 3;
++last;
iov[last].iov_base = _itoa_word ((unsigned long int) diff,
&buf2[WORD_WIDTH], 16, 0);
iov[last].iov_len = (&buf2[WORD_WIDTH]
- (char *) iov[last].iov_base);
++last;
iov[last].iov_base = (void *) ")";
iov[last].iov_len = 1;
++last;
}
}
iov[last].iov_base = (void *) "[0x";
iov[last].iov_len = 3;
++last;
iov[last].iov_base = _itoa_word ((unsigned long int) array[cnt],
&buf[WORD_WIDTH], 16, 0);
iov[last].iov_len = &buf[WORD_WIDTH] - (char *) iov[last].iov_base;
++last;
iov[last].iov_base = (void *) "]\n";
iov[last].iov_len = 2;
++last;
__writev (fd, iov, last);
}
}
