1 files changed, 135 insertions, 20 deletions

diff --git a/src/common/compat.c b/src/common/compat.c
index fc066da68..330c43228 100644
--- a/src/common/compat.c
+++ b/src/common/compat.c
@@ -103,6 +103,35 @@
 #include "strlcat.c"
 #endif
 
+/** As open(path, flags, mode), but return an fd with the close-on-exec mode
+ * set. */
+int
+tor_open_cloexec(const char *path, int flags, unsigned mode)
+{
+#ifdef O_CLOEXEC
+  return open(path, flags|O_CLOEXEC, mode);
+#else
+  int fd = open(path, flags, mode);
+#ifdef FD_CLOEXEC
+  if (fd >= 0)
+        fcntl(fd, F_SETFD, FD_CLOEXEC);
+#endif
+  return fd;
+#endif
+}
+
+/** DOCDOC */
+FILE *
+tor_fopen_cloexec(const char *path, const char *mode)
+{
+  FILE *result = fopen(path, mode);
+#ifdef FD_CLOEXEC
+  if (result != NULL)
+    fcntl(fileno(result), F_SETFD, FD_CLOEXEC);
+#endif
+  return result;
+}
+
 #ifdef HAVE_SYS_MMAN_H
 /** Try to create a memory mapping for <b>filename</b> and return it.  On
  * failure, return NULL.  Sets errno properly, using ERANGE to mean
@@ -118,7 +147,7 @@ tor_mmap_file(const char *filename)
 
   tor_assert(filename);
 
-  fd = open(filename, O_RDONLY, 0);
+  fd = tor_open_cloexec(filename, O_RDONLY, 0);
   if (fd<0) {
     int save_errno = errno;
     int severity = (errno == ENOENT) ? LOG_INFO : LOG_WARN;
@@ -415,7 +444,7 @@ tor_vasprintf(char **strp, const char *fmt, va_list args)
  *
  * This function is <em>not</em> timing-safe.
  *
- * Requires that nlen be greater than zero.
+ * Requires that <b>nlen</b> be greater than zero.
  */
 const void *
 tor_memmem(const void *_haystack, size_t hlen,
@@ -695,7 +724,7 @@ tor_lockfile_lock(const char *filename, int blocking, int *locked_out)
   *locked_out = 0;
 
   log_info(LD_FS, "Locking \"%s\"", filename);
-  fd = open(filename, O_RDWR|O_CREAT|O_TRUNC, 0600);
+  fd = tor_open_cloexec(filename, O_RDWR|O_CREAT|O_TRUNC, 0600);
   if (fd < 0) {
     log_warn(LD_FS,"Couldn't open \"%s\" for locking: %s", filename,
              strerror(errno));
@@ -841,7 +870,7 @@ socket_accounting_unlock(void)
  * Windows, where close()ing a socket doesn't work.  Returns 0 on success, -1
  * on failure. */
 int
-tor_close_socket(int s)
+tor_close_socket(tor_socket_t s)
 {
   int r = 0;
 
@@ -894,8 +923,10 @@ tor_close_socket(int s)
 /** Helper: if DEBUG_SOCKET_COUNTING is enabled, remember that <b>s</b> is
  * now an open socket. */
 static INLINE void
-mark_socket_open(int s)
+mark_socket_open(tor_socket_t s)
 {
+  /* XXXX This bitarray business will NOT work on windows: sockets aren't
+     small ints there. */
   if (s > max_socket) {
     if (max_socket == -1) {
       open_sockets = bitarray_init_zero(s+128);
@@ -917,11 +948,19 @@ mark_socket_open(int s)
 /** @} */
 
 /** As socket(), but counts the number of open sockets. */
-int
+tor_socket_t
 tor_open_socket(int domain, int type, int protocol)
 {
-  int s = socket(domain, type, protocol);
-  if (s >= 0) {
+  tor_socket_t s;
+#ifdef SOCK_CLOEXEC
+#define LINUX_CLOEXEC_OPEN_SOCKET
+  type |= SOCK_CLOEXEC;
+#endif
+  s = socket(domain, type, protocol);
+  if (SOCKET_OK(s)) {
+#if !defined(LINUX_CLOEXEC_OPEN_SOCKET) && defined(FD_CLOEXEC)
+    fcntl(s, F_SETFD, FD_CLOEXEC);
+#endif
     socket_accounting_lock();
     ++n_sockets_open;
     mark_socket_open(s);
@@ -931,11 +970,20 @@ tor_open_socket(int domain, int type, int protocol)
 }
 
 /** As socket(), but counts the number of open sockets. */
-int
+tor_socket_t
 tor_accept_socket(int sockfd, struct sockaddr *addr, socklen_t *len)
 {
-  int s = accept(sockfd, addr, len);
-  if (s >= 0) {
+  tor_socket_t s;
+#if defined(HAVE_ACCEPT4) && defined(SOCK_CLOEXEC)
+#define LINUX_CLOEXEC_ACCEPT
+  s = accept4(sockfd, addr, len, SOCK_CLOEXEC);
+#else
+  s = accept(sockfd, addr, len);
+#endif
+  if (SOCKET_OK(s)) {
+#if !defined(LINUX_CLOEXEC_ACCEPT) && defined(FD_CLOEXEC)
+    fcntl(s, F_SETFD, FD_CLOEXEC);
+#endif
     socket_accounting_lock();
     ++n_sockets_open;
     mark_socket_open(s);
@@ -958,7 +1006,7 @@ get_n_open_sockets(void)
 /** Turn <b>socket</b> into a nonblocking socket.
  */
 void
-set_socket_nonblocking(int socket)
+set_socket_nonblocking(tor_socket_t socket)
 {
 #if defined(MS_WINDOWS)
   unsigned long nonblocking = 1;
@@ -986,13 +1034,22 @@ set_socket_nonblocking(int socket)
  **/
 /* It would be nicer just to set errno, but that won't work for windows. */
 int
-tor_socketpair(int family, int type, int protocol, int fd[2])
+tor_socketpair(int family, int type, int protocol, tor_socket_t fd[2])
 {
 //don't use win32 socketpairs (they are always bad)
 #if defined(HAVE_SOCKETPAIR) && !defined(MS_WINDOWS)
   int r;
+#ifdef SOCK_CLOEXEC
+  type |= SOCK_CLOEXEC;
+#endif
   r = socketpair(family, type, protocol, fd);
   if (r == 0) {
+#if !defined(SOCK_CLOEXEC) && defined(FD_CLOEXEC)
+    if (fd[0] >= 0)
+      fcntl(fd[0], F_SETFD, FD_CLOEXEC);
+    if (fd[1] >= 0)
+      fcntl(fd[1], F_SETFD, FD_CLOEXEC);
+#endif
     socket_accounting_lock();
     if (fd[0] >= 0) {
       ++n_sockets_open;
@@ -1011,9 +1068,9 @@ tor_socketpair(int family, int type, int protocol, int fd[2])
      * for now, and really, when localhost is down sometimes, we
      * have other problems too.
      */
-    int listener = -1;
-    int connector = -1;
-    int acceptor = -1;
+    tor_socket_t listener = -1;
+    tor_socket_t connector = -1;
+    tor_socket_t acceptor = -1;
     struct sockaddr_in listen_addr;
     struct sockaddr_in connect_addr;
     int size;
@@ -1223,7 +1280,8 @@ log_credential_status(void)
   /* Read, effective and saved GIDs */
   gid_t rgid, egid, sgid;
   /* Supplementary groups */
-  gid_t sup_gids[NGROUPS_MAX + 1];
+  gid_t *sup_gids = NULL;
+  int sup_gids_size;
   /* Number of supplementary groups */
   int ngids;
 
@@ -1269,9 +1327,19 @@ log_credential_status(void)
 #endif
 
   /* log supplementary groups */
-  if ((ngids = getgroups(NGROUPS_MAX + 1, sup_gids)) < 0) {
+  sup_gids_size = 64;
+  sup_gids = tor_malloc(sizeof(gid_t) * 64);
+  while ((ngids = getgroups(sup_gids_size, sup_gids)) < 0 &&
+         errno == EINVAL &&
+         sup_gids_size < NGROUPS_MAX) {
+    sup_gids_size *= 2;
+    sup_gids = tor_realloc(sup_gids, sizeof(gid_t) * sup_gids_size);
+  }
+
+  if (ngids < 0) {
     log_warn(LD_GENERAL, "Error getting supplementary GIDs: %s",
              strerror(errno));
+    tor_free(sup_gids);
     return -1;
   } else {
     int i, retval = 0;
@@ -1301,6 +1369,7 @@ log_credential_status(void)
       tor_free(cp);
     });
     smartlist_free(elts);
+    tor_free(sup_gids);
 
     return retval;
   }
@@ -1980,6 +2049,52 @@ spawn_exit(void)
 #endif
 }
 
+/** Implementation logic for compute_num_cpus(). */
+static int
+compute_num_cpus_impl(void)
+{
+#ifdef MS_WINDOWS
+  SYSTEM_INFO info;
+  memset(&info, 0, sizeof(info));
+  GetSystemInfo(&info);
+  if (info.dwNumberOfProcessors >= 1 && info.dwNumberOfProcessors < INT_MAX)
+    return (int)info.dwNumberOfProcessors;
+  else
+    return -1;
+#elif defined(HAVE_SYSCONF) && defined(_SC_NPROCESSORS_CONF)
+  long cpus = sysconf(_SC_NPROCESSORS_CONF);
+  if (cpus >= 1 && cpus < INT_MAX)
+    return (int)cpus;
+  else
+    return -1;
+#else
+  return -1;
+#endif
+}
+
+#define MAX_DETECTABLE_CPUS 16
+
+/** Return how many CPUs we are running with.  We assume that nobody is
+ * using hot-swappable CPUs, so we don't recompute this after the first
+ * time.  Return -1 if we don't know how to tell the number of CPUs on this
+ * system.
+ */
+int
+compute_num_cpus(void)
+{
+  static int num_cpus = -2;
+  if (num_cpus == -2) {
+    num_cpus = compute_num_cpus_impl();
+    tor_assert(num_cpus != -2);
+    if (num_cpus > MAX_DETECTABLE_CPUS)
+      log_notice(LD_GENERAL, "Wow!  I detected that you have %d CPUs. I "
+                 "will not autodetect any more than %d, though.  If you "
+                 "want to configure more, set NumCPUs in your torrc",
+                 num_cpus, MAX_DETECTABLE_CPUS);
+  }
+  return num_cpus;
+}
+
 /** Set *timeval to the current time of day.  On error, log and terminate.
  * (Same as gettimeofday(timeval,NULL), but never returns -1.)
  */
@@ -2577,11 +2692,11 @@ in_main_thread(void)
  */
 #if defined(MS_WINDOWS)
 int
-tor_socket_errno(int sock)
+tor_socket_errno(tor_socket_t sock)
 {
   int optval, optvallen=sizeof(optval);
   int err = WSAGetLastError();
-  if (err == WSAEWOULDBLOCK && sock >= 0) {
+  if (err == WSAEWOULDBLOCK && SOCKET_OK(sock)) {
     if (getsockopt(sock, SOL_SOCKET, SO_ERROR, (void*)&optval, &optvallen))
       return err;
     if (optval)