Adding upstream version 7.94+git20230807.3be01efb1+dfsg.upstream/7.94+git20230807.3be01efb1+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 368 insertions, 0 deletions

diff --git a/nsock/src/engine_kqueue.c b/nsock/src/engine_kqueue.c
new file mode 100644
index 0000000..aa992bb
--- /dev/null
+++ b/nsock/src/engine_kqueue.c
@@ -0,0 +1,368 @@
+/***************************************************************************
+ * engine_kqueue.c -- BSD kqueue(2) based IO engine.                       *
+ *                                                                         *
+ ***********************IMPORTANT NSOCK LICENSE TERMS***********************
+ *
+ * The nsock parallel socket event library is (C) 1999-2023 Nmap Software LLC
+ * This library is free software; you may redistribute and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; Version 2. This guarantees your right to use, modify, and
+ * redistribute this software under certain conditions. If this license is
+ * unacceptable to you, Nmap Software LLC may be willing to sell alternative
+ * licenses (contact sales@nmap.com ).
+ *
+ * As a special exception to the GPL terms, Nmap Software LLC grants permission
+ * to link the code of this program with any version of the OpenSSL library
+ * which is distributed under a license identical to that listed in the included
+ * docs/licenses/OpenSSL.txt file, and distribute linked combinations including
+ * the two. You must obey the GNU GPL in all respects for all of the code used
+ * other than OpenSSL. If you modify this file, you may extend this exception to
+ * your version of the file, but you are not obligated to do so.
+ *
+ * If you received these files with a written license agreement stating terms
+ * other than the (GPL) terms above, then that alternative license agreement
+ * takes precedence over this comment.
+ *
+ * Source is provided to this software because we believe users have a right to
+ * know exactly what a program is going to do before they run it. This also
+ * allows you to audit the software for security holes.
+ *
+ * Source code also allows you to port Nmap to new platforms, fix bugs, and add
+ * new features. You are highly encouraged to send your changes to the
+ * dev@nmap.org mailing list for possible incorporation into the main
+ * distribution. By sending these changes to Fyodor or one of the Insecure.Org
+ * development mailing lists, or checking them into the Nmap source code
+ * repository, it is understood (unless you specify otherwise) that you are
+ * offering the Nmap Project (Nmap Software LLC) the unlimited, non-exclusive
+ * right to reuse, modify, and relicense the code. Nmap will always be available
+ * Open Source, but this is important because the inability to relicense code
+ * has caused devastating problems for other Free Software projects (such as KDE
+ * and NASM). We also occasionally relicense the code to third parties as
+ * discussed above. If you wish to specify special license conditions of your
+ * contributions, just say so when you send them.
+ *
+ * This program 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 General Public License v2.0 for more
+ * details (http://www.gnu.org/licenses/gpl-2.0.html).
+ *
+ ***************************************************************************/
+
+/* $Id$ */
+
+#ifdef HAVE_CONFIG_H
+#include "nsock_config.h"
+#endif
+
+#if HAVE_KQUEUE
+
+#include <sys/types.h>
+#include <sys/event.h>
+#include <sys/time.h>
+#include <errno.h>
+
+#include "nsock_internal.h"
+#include "nsock_log.h"
+
+#if HAVE_PCAP
+#include "nsock_pcap.h"
+#endif
+
+#define INITIAL_EV_COUNT  128
+
+
+/* --- ENGINE INTERFACE PROTOTYPES --- */
+static int kqueue_init(struct npool *nsp);
+static void kqueue_destroy(struct npool *nsp);
+static int kqueue_iod_register(struct npool *nsp, struct niod *iod, struct nevent *nse, int ev);
+static int kqueue_iod_unregister(struct npool *nsp, struct niod *iod);
+static int kqueue_iod_modify(struct npool *nsp, struct niod *iod, struct nevent *nse, int ev_set, int ev_clr);
+static int kqueue_loop(struct npool *nsp, int msec_timeout);
+
+extern struct io_operations posix_io_operations;
+
+/* ---- ENGINE DEFINITION ---- */
+struct io_engine engine_kqueue = {
+  "kqueue",
+  kqueue_init,
+  kqueue_destroy,
+  kqueue_iod_register,
+  kqueue_iod_unregister,
+  kqueue_iod_modify,
+  kqueue_loop,
+  &posix_io_operations
+};
+
+
+/* --- INTERNAL PROTOTYPES --- */
+static void iterate_through_event_lists(struct npool *nsp, int evcount);
+
+/* defined in nsock_core.c */
+void process_iod_events(struct npool *nsp, struct niod *nsi, int ev);
+void process_event(struct npool *nsp, gh_list_t *evlist, struct nevent *nse, int ev);
+void process_expired_events(struct npool *nsp);
+#if HAVE_PCAP
+#ifndef PCAP_CAN_DO_SELECT
+int pcap_read_on_nonselect(struct npool *nsp);
+#endif
+#endif
+
+/* defined in nsock_event.c */
+void update_first_events(struct nevent *nse);
+
+
+extern struct timeval nsock_tod;
+
+
+/*
+ * Engine specific data structure
+ */
+struct kqueue_engine_info {
+  int kqfd;
+  int maxfd;
+  size_t evlen;
+  struct kevent *events;
+};
+
+
+int kqueue_init(struct npool *nsp) {
+  struct kqueue_engine_info *kinfo;
+
+  kinfo = (struct kqueue_engine_info *)safe_malloc(sizeof(struct kqueue_engine_info));
+
+  kinfo->kqfd = kqueue();
+  kinfo->maxfd = -1;
+  kinfo->evlen = INITIAL_EV_COUNT;
+  kinfo->events = (struct kevent *)safe_malloc(INITIAL_EV_COUNT * sizeof(struct kevent));
+
+  nsp->engine_data = (void *)kinfo;
+
+  return 1;
+}
+
+void kqueue_destroy(struct npool *nsp) {
+  struct kqueue_engine_info *kinfo = (struct kqueue_engine_info *)nsp->engine_data;
+
+  assert(kinfo != NULL);
+  close(kinfo->kqfd);
+  free(kinfo->events);
+  free(kinfo);
+}
+
+int kqueue_iod_register(struct npool *nsp, struct niod *iod, struct nevent *nse, int ev) {
+  struct kqueue_engine_info *kinfo = (struct kqueue_engine_info *)nsp->engine_data;
+
+  assert(!IOD_PROPGET(iod, IOD_REGISTERED));
+
+  IOD_PROPSET(iod, IOD_REGISTERED);
+  iod->watched_events = EV_NONE;
+
+  kqueue_iod_modify(nsp, iod, nse, ev, EV_NONE);
+
+  if (nsock_iod_get_sd(iod) > kinfo->maxfd)
+    kinfo->maxfd = nsock_iod_get_sd(iod);
+
+  return 1;
+}
+
+int kqueue_iod_unregister(struct npool *nsp, struct niod *iod) {
+  struct kqueue_engine_info *kinfo = (struct kqueue_engine_info *)nsp->engine_data;
+
+  /* some IODs can be unregistered here if they're associated to an event that was
+   * immediately completed */
+  if (IOD_PROPGET(iod, IOD_REGISTERED)) {
+    kqueue_iod_modify(nsp, iod, NULL, EV_NONE, EV_READ|EV_WRITE);
+    IOD_PROPCLR(iod, IOD_REGISTERED);
+
+    if (nsock_iod_get_sd(iod) == kinfo->maxfd)
+      kinfo->maxfd--;
+  }
+  iod->watched_events = EV_NONE;
+  return 1;
+}
+
+#define EV_SETFLAG(_set, _ev) (((_set) & (_ev)) ? (EV_ADD|EV_ENABLE) : (EV_ADD|EV_DISABLE))
+
+int kqueue_iod_modify(struct npool *nsp, struct niod *iod, struct nevent *nse, int ev_set, int ev_clr) {
+  struct kevent kev[2];
+  int new_events, i;
+  struct kqueue_engine_info *kinfo = (struct kqueue_engine_info *)nsp->engine_data;
+
+  assert((ev_set & ev_clr) == 0);
+  assert(IOD_PROPGET(iod, IOD_REGISTERED));
+
+  new_events = iod->watched_events;
+  new_events |= ev_set;
+  new_events &= ~ev_clr;
+
+  if (new_events == iod->watched_events)
+    return 1; /* nothing to do */
+
+  i = 0;
+  if ((ev_set ^ ev_clr) & EV_READ) {
+    EV_SET(&kev[i], nsock_iod_get_sd(iod), EVFILT_READ, EV_SETFLAG(ev_set, EV_READ), 0, 0, (void *)iod);
+    i++;
+  }
+  if ((ev_set ^ ev_clr) & EV_WRITE) {
+    EV_SET(&kev[i], nsock_iod_get_sd(iod), EVFILT_WRITE, EV_SETFLAG(ev_set, EV_WRITE), 0, 0, (void *)iod);
+    i++;
+  }
+
+  if (i > 0 && kevent(kinfo->kqfd, kev, i, NULL, 0, NULL) < 0)
+    fatal("Unable to update events for IOD #%lu: %s", iod->id, strerror(errno));
+
+  iod->watched_events = new_events;
+  return 1;
+}
+
+int kqueue_loop(struct npool *nsp, int msec_timeout) {
+  int results_left = 0;
+  int event_msecs; /* msecs before an event goes off */
+  int combined_msecs;
+  struct timespec ts, *ts_p;
+  int sock_err = 0;
+  struct kqueue_engine_info *kinfo = (struct kqueue_engine_info *)nsp->engine_data;
+
+  assert(msec_timeout >= -1);
+
+  if (nsp->events_pending == 0)
+    return 0; /* No need to wait on 0 events ... */
+
+
+  if (gh_list_count(&nsp->active_iods) > kinfo->evlen) {
+    kinfo->evlen = gh_list_count(&nsp->active_iods) * 2;
+    kinfo->events = (struct kevent *)safe_realloc(kinfo->events, kinfo->evlen * sizeof(struct kevent));
+  }
+
+  do {
+    struct nevent *nse;
+
+    nsock_log_debug_all("wait for events");
+
+    nse = next_expirable_event(nsp);
+    if (!nse)
+      event_msecs = -1; /* None of the events specified a timeout */
+    else
+      event_msecs = MAX(0, TIMEVAL_MSEC_SUBTRACT(nse->timeout, nsock_tod));
+
+#if HAVE_PCAP
+#ifndef PCAP_CAN_DO_SELECT
+    /* Force a low timeout when capturing packets on systems where
+     * the pcap descriptor is not select()able. */
+    if (gh_list_count(&nsp->pcap_read_events) > 0)
+      if (event_msecs > PCAP_POLL_INTERVAL)
+        event_msecs = PCAP_POLL_INTERVAL;
+#endif
+#endif
+
+    /* We cast to unsigned because we want -1 to be very high (since it means no
+     * timeout) */
+    combined_msecs = MIN((unsigned)event_msecs, (unsigned)msec_timeout);
+
+    /* Set up the timeval pointer we will give to kevent() */
+    memset(&ts, 0, sizeof(struct timespec));
+    if (combined_msecs >= 0) {
+      ts.tv_sec = combined_msecs / 1000;
+      ts.tv_nsec = (combined_msecs % 1000) * 1000000L;
+      ts_p = &ts;
+    } else {
+      ts_p = NULL;
+    }
+
+#if HAVE_PCAP
+#ifndef PCAP_CAN_DO_SELECT
+    /* do non-blocking read on pcap devices that doesn't support select()
+     * If there is anything read, just leave this loop. */
+    if (pcap_read_on_nonselect(nsp)) {
+      /* okay, something was read. */
+    } else
+#endif
+#endif
+    {
+      results_left = kevent(kinfo->kqfd, NULL, 0, kinfo->events, kinfo->evlen, ts_p);
+      if (results_left == -1)
+        sock_err = socket_errno();
+    }
+
+    gettimeofday(&nsock_tod, NULL); /* Due to kevent delay */
+  } while (results_left == -1 && sock_err == EINTR); /* repeat only if signal occurred */
+
+  if (results_left == -1 && sock_err != EINTR) {
+    nsock_log_error("nsock_loop error %d: %s", sock_err, socket_strerror(sock_err));
+    nsp->errnum = sock_err;
+    return -1;
+  }
+
+  iterate_through_event_lists(nsp, results_left);
+
+  return 1;
+}
+
+
+/* ---- INTERNAL FUNCTIONS ---- */
+
+static inline int get_evmask(struct niod *nsi, const struct kevent *kev) {
+  int evmask = EV_NONE;
+
+  /* generate the corresponding event mask with nsock event flags */
+  if (kev->flags & EV_ERROR) {
+    evmask |= EV_EXCEPT;
+
+    if (kev->data == EPIPE && (nsi->watched_events & EV_READ))
+      evmask |= EV_READ;
+  } else {
+    switch (kev->filter) {
+      case EVFILT_READ:
+        evmask |= EV_READ;
+        break;
+
+      case EVFILT_WRITE:
+        evmask |= EV_WRITE;
+        break;
+
+      default:
+        fatal("Unsupported filter value: %d\n", (int)kev->filter);
+    }
+  }
+  return evmask;
+}
+
+/* Iterate through all the event lists (such as connect_events, read_events,
+ * timer_events, etc) and take action for those that have completed (due to
+ * timeout, i/o, etc) */
+void iterate_through_event_lists(struct npool *nsp, int evcount) {
+  int n;
+  struct kqueue_engine_info *kinfo = (struct kqueue_engine_info *)nsp->engine_data;
+  struct niod *nsi;
+
+  for (n = 0; n < evcount; n++) {
+    struct kevent *kev = &kinfo->events[n];
+
+    nsi = (struct niod *)kev->udata;
+
+    /* process all the pending events for this IOD */
+    process_iod_events(nsp, nsi, get_evmask(nsi, kev));
+
+    IOD_PROPSET(nsi, IOD_PROCESSED);
+  }
+
+  for (n = 0; n < evcount; n++) {
+    struct kevent *kev = &kinfo->events[n];
+
+    nsi = (struct niod *)kev->udata;
+
+    if (nsi->state == NSIOD_STATE_DELETED) {
+      if (IOD_PROPGET(nsi, IOD_PROCESSED)) {
+        IOD_PROPCLR(nsi, IOD_PROCESSED);
+        gh_list_remove(&nsp->active_iods, &nsi->nodeq);
+        gh_list_prepend(&nsp->free_iods, &nsi->nodeq);
+      }
+    }
+  }
+
+  /* iterate through timers and expired events */
+  process_expired_events(nsp);
+}
+
+#endif /* HAVE_KQUEUE */
+