[src/trunk]: src/usr.sbin/npf/npfd try to re-open the pcap connection on error.

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/93f09a78ecfa
branches:  trunk
changeset: 356825:93f09a78ecfa
user:      christos <christos%NetBSD.org@localhost>
date:      Sun Oct 15 15:26:10 2017 +0000

description:
try to re-open the pcap connection on error.

diffstat:

 usr.sbin/npf/npfd/npfd.c     |   9 ++--
 usr.sbin/npf/npfd/npfd.h     |   7 ++-
 usr.sbin/npf/npfd/npfd_log.c |  76 ++++++++++++++++++++++++++++---------------
 3 files changed, 59 insertions(+), 33 deletions(-)

diffs (216 lines):

diff -r c42d96926abd -r 93f09a78ecfa usr.sbin/npf/npfd/npfd.c
--- a/usr.sbin/npf/npfd/npfd.c  Sun Oct 15 14:41:06 2017 +0000
+++ b/usr.sbin/npf/npfd/npfd.c  Sun Oct 15 15:26:10 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npfd.c,v 1.7 2017/01/24 20:24:59 christos Exp $        */
+/*     $NetBSD: npfd.c,v 1.8 2017/10/15 15:26:10 christos Exp $        */
 
 /*-
  * Copyright (c) 2015 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: npfd.c,v 1.7 2017/01/24 20:24:59 christos Exp $");
+__RCSID("$NetBSD: npfd.c,v 1.8 2017/10/15 15:26:10 christos Exp $");
 
 #include <stdio.h>
 #include <string.h>
@@ -83,7 +83,7 @@
        while  (!done) {
                if (hup) {
                        hup = false;
-                       npfd_log_reopen(log, false);
+                       npfd_log_file_reopen(log, false);
                }
                if (stats) {
                        stats = false;
@@ -110,7 +110,8 @@
                                npfd_log_flush(log);
                                count = 0;
                        }
-                       npfd_log(log);
+                       if (npfd_log(log) < 0)
+                               npfd_log_pcap_reopen(log);
                }
 
        }
diff -r c42d96926abd -r 93f09a78ecfa usr.sbin/npf/npfd/npfd.h
--- a/usr.sbin/npf/npfd/npfd.h  Sun Oct 15 14:41:06 2017 +0000
+++ b/usr.sbin/npf/npfd/npfd.h  Sun Oct 15 15:26:10 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npfd.h,v 1.4 2017/01/06 19:20:24 christos Exp $        */
+/*     $NetBSD: npfd.h,v 1.5 2017/10/15 15:26:10 christos Exp $        */
 
 /*-
  * Copyright (c) 2015 The NetBSD Foundation, Inc.
@@ -45,8 +45,9 @@
 npfd_log_t *   npfd_log_create(const char *, const char *, const char *, int);
 void           npfd_log_destroy(npfd_log_t *);
 int            npfd_log_getsock(npfd_log_t *);
-bool           npfd_log_reopen(npfd_log_t *, bool);
-void           npfd_log(npfd_log_t *);
+bool           npfd_log_file_reopen(npfd_log_t *, bool);
+bool           npfd_log_pcap_reopen(npfd_log_t *);
+int            npfd_log(npfd_log_t *);
 void           npfd_log_stats(npfd_log_t *);
 void           npfd_log_flush(npfd_log_t *);
 
diff -r c42d96926abd -r 93f09a78ecfa usr.sbin/npf/npfd/npfd_log.c
--- a/usr.sbin/npf/npfd/npfd_log.c      Sun Oct 15 14:41:06 2017 +0000
+++ b/usr.sbin/npf/npfd/npfd_log.c      Sun Oct 15 15:26:10 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npfd_log.c,v 1.10 2017/03/25 11:00:27 christos Exp $   */
+/*     $NetBSD: npfd_log.c,v 1.11 2017/10/15 15:26:10 christos Exp $   */
 
 /*-
  * Copyright (c) 2015 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: npfd_log.c,v 1.10 2017/03/25 11:00:27 christos Exp $");
+__RCSID("$NetBSD: npfd_log.c,v 1.11 2017/10/15 15:26:10 christos Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -39,6 +39,7 @@
 #include <net/if.h>
 
 #include <stdio.h>
+#include <string.h>
 #include <err.h>
 #include <inttypes.h>
 #include <limits.h>
@@ -53,18 +54,23 @@
 struct npfd_log {
        char ifname[IFNAMSIZ];
        char path[MAXPATHLEN];
+       char *filter;
+       int snaplen;
        pcap_t *pcap;
        pcap_dumper_t *dumper;
 };
 
 static void
-npfd_log_setfilter(npfd_log_t *ctx, const char *filter)
+npfd_log_setfilter(npfd_log_t *ctx)
 {
        struct bpf_program bprog;
 
-       if (pcap_compile(ctx->pcap, &bprog, filter, 1, 0) == -1)
-               errx(EXIT_FAILURE, "pcap_compile failed for `%s': %s", filter,
-                   pcap_geterr(ctx->pcap));
+       if (ctx->filter == NULL)
+               return;
+
+       if (pcap_compile(ctx->pcap, &bprog, ctx->filter, 1, 0) == -1)
+               errx(EXIT_FAILURE, "pcap_compile failed for `%s': %s",
+                   ctx->filter, pcap_geterr(ctx->pcap));
        if (pcap_setfilter(ctx->pcap, &bprog) == -1)
                errx(EXIT_FAILURE, "pcap_setfilter failed: %s",
                    pcap_geterr(ctx->pcap));
@@ -206,15 +212,42 @@
     int snaplen)
 {
        npfd_log_t *ctx;
-       char errbuf[PCAP_ERRBUF_SIZE];
 
        if ((ctx = calloc(1, sizeof(*ctx))) == NULL)
                err(EXIT_FAILURE, "malloc failed");
 
-       /*
-        * Open a live capture handle in non-blocking mode.
-        */
        snprintf(ctx->ifname, sizeof(ctx->ifname), "%s", ifname);
+       if (filename == NULL)
+               snprintf(ctx->path, sizeof(ctx->path), NPFD_LOG_PATH "/%s.pcap",
+                   ctx->ifname);
+       else
+               snprintf(ctx->path, sizeof(ctx->path), "%s", filename);
+
+       if (filter != NULL) {
+               ctx->filter = strdup(filter);
+               if (ctx->filter == NULL)
+                       err(EXIT_FAILURE, "malloc failed");
+       }
+       ctx->snaplen = snaplen;
+
+       /* Open a live capture handle in non-blocking mode.  */
+       npfd_log_pcap_reopen(ctx);
+
+       /* Open the log file */
+       npfd_log_file_reopen(ctx, false);
+       return ctx;
+}
+
+
+bool
+npfd_log_pcap_reopen(npfd_log_t *ctx)
+{
+       char errbuf[PCAP_ERRBUF_SIZE];
+       int snaplen = ctx->snaplen;
+
+       if (ctx->pcap != NULL)
+               pcap_close(ctx->pcap);
+
        ctx->pcap = pcap_create(ctx->ifname, errbuf);
        if (ctx->pcap == NULL)
                errx(EXIT_FAILURE, "pcap_create failed: %s", errbuf);
@@ -222,19 +255,13 @@
        if (pcap_setnonblock(ctx->pcap, 1, errbuf) == -1)
                errx(EXIT_FAILURE, "pcap_setnonblock failed: %s", errbuf);
 
-       if (filename == NULL)
-               snprintf(ctx->path, sizeof(ctx->path), NPFD_LOG_PATH "/%s.pcap",
-                   ctx->ifname);
-       else
-               snprintf(ctx->path, sizeof(ctx->path), "%s", filename);
-
        int sl = npfd_log_getsnaplen(ctx);
        if (sl == -1)
                errx(EXIT_FAILURE, "corrupt log file `%s'", ctx->path);
 
        if (sl != 0 && sl != snaplen) {
                warnx("Overriding snaplen from %d to %d from `%s'", snaplen,
-                   sl, filename);
+                   sl, ctx->path);
                snaplen = sl;
        }
 
@@ -250,16 +277,12 @@
                errx(EXIT_FAILURE, "pcap_activate failed: %s",
                    pcap_geterr(ctx->pcap));
 
-       if (filter)
-               npfd_log_setfilter(ctx, filter);
-
-
-       npfd_log_reopen(ctx, false);
-       return ctx;
+       npfd_log_setfilter(ctx);
+       return true;
 }
 
 bool
-npfd_log_reopen(npfd_log_t *ctx, bool die)
+npfd_log_file_reopen(npfd_log_t *ctx, bool die)
 {
        mode_t omask = umask(077);
 
@@ -320,12 +343,13 @@
 }
 
 
-void
+int
 npfd_log(npfd_log_t *ctx)
 {
        pcap_dumper_t *dumper = ctx->dumper;
 
-       pcap_dispatch(ctx->pcap, PCAP_NPACKETS, pcap_dump, (void *)dumper);
+       return pcap_dispatch(ctx->pcap, PCAP_NPACKETS, pcap_dump,
+           (void *)dumper);
 }
 
 void