glibc/elf/dl-audit.c

/* Audit common functions.
   Copyright (C) 2021 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#include <ldsodefs.h>

void
_dl_audit_activity_map (struct link_map *l, int action)
{
  struct audit_ifaces *afct = GLRO(dl_audit);
  for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
    {
      if (afct->activity != NULL)
	afct->activity (&link_map_audit_state (l, cnt)->cookie, action);
      afct = afct->next;
    }
}

void
_dl_audit_activity_nsid (Lmid_t nsid, int action)
{
  /* If head is NULL, the namespace has become empty, and the audit interface
     does not give us a way to signal LA_ACT_CONSISTENT for it because the
     first loaded module is used to identify the namespace.  */
  struct link_map *head = GL(dl_ns)[nsid]._ns_loaded;
  if (__glibc_likely (GLRO(dl_naudit) == 0)
      || head == NULL || head->l_auditing)
    return;

  _dl_audit_activity_map (head, action);
}

const char *
_dl_audit_objsearch (const char *name, struct link_map *l, unsigned int code)
{
  if (l == NULL || l->l_auditing || code == 0)
    return name;

  struct audit_ifaces *afct = GLRO(dl_audit);
  for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
    {
      if (afct->objsearch != NULL)
	{
	  struct auditstate *state = link_map_audit_state (l, cnt);
	  name = afct->objsearch (name, &state->cookie, code);
	  if (name == NULL)
	    return NULL;
	}
      afct = afct->next;
   }

  return name;
}

void
_dl_audit_objopen (struct link_map *l, Lmid_t nsid)
{
  if (__glibc_likely (GLRO(dl_naudit) == 0))
    return;

  struct audit_ifaces *afct = GLRO(dl_audit);
  for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
    {
      if (afct->objopen != NULL)
	{
	  struct auditstate *state = link_map_audit_state (l, cnt);
	  state->bindflags = afct->objopen (l, nsid, &state->cookie);
	  l->l_audit_any_plt |= state->bindflags != 0;
	}

      afct = afct->next;
   }
}

void
_dl_audit_objclose (struct link_map *l)
{
  if (__glibc_likely (GLRO(dl_naudit) == 0)
      || GL(dl_ns)[l->l_ns]._ns_loaded->l_auditing)
    return;

  struct audit_ifaces *afct = GLRO(dl_audit);
  for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
    {
      if (afct->objclose != NULL)
	{
	  struct auditstate *state= link_map_audit_state (l, cnt);
	  /* Return value is ignored.  */
	  afct->objclose (&state->cookie);
	}

      afct = afct->next;
    }
}