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diff -urN ppp.old/pppd/Makefile.linux ppp.dev/pppd/Makefile.linux
--- ppp.old/pppd/Makefile.linux 2006-03-18 15:58:00.000000000 +0100
+++ ppp.dev/pppd/Makefile.linux 2006-03-18 16:52:01.000000000 +0100
@@ -50,6 +50,9 @@
# and that the kernel driver support PPP packet filtering.
#FILTER=y
+# Support for precompiled filters
+PRECOMPILED_FILTER=y
+
# Uncomment the next line to enable multilink PPP (enabled by default)
# Linux distributions: Please leave multilink ENABLED in your builds
# of pppd!
@@ -177,6 +180,14 @@
endif
endif
+ifdef PRECOMPILED_FILTER
+PPPDSRCS += pcap_pcc.c
+HEADERS += pcap_pcc.h
+PPPDOBJS += pcap_pcc.o
+LIBS += $(STAGING_DIR)/usr/lib/libpcap.a
+CFLAGS += -DPPP_FILTER -DPPP_PRECOMPILED_FILTER -I$(STAGING_DIR)/usr/include
+endif
+
ifdef HAVE_INET6
PPPDSRCS += ipv6cp.c eui64.c
HEADERS += ipv6cp.h eui64.h
diff -urN ppp.old/pppd/demand.c ppp.dev/pppd/demand.c
--- ppp.old/pppd/demand.c 2006-03-18 15:58:00.000000000 +0100
+++ ppp.dev/pppd/demand.c 2006-03-18 18:09:16.000000000 +0100
@@ -438,12 +438,14 @@
return 0;
proto = PPP_PROTOCOL(p);
#ifdef PPP_FILTER
+ *p = 1; /* set outbound for the filter rule */
if (pass_filter.bf_len != 0
&& bpf_filter(pass_filter.bf_insns, p, len, len) == 0)
return 0;
if (active_filter.bf_len != 0
&& bpf_filter(active_filter.bf_insns, p, len, len) == 0)
return 0;
+ *p = 0xff; /* restore original ppp header */
#endif
for (i = 0; (protp = protocols[i]) != NULL; ++i) {
if (protp->protocol < 0xC000 && (protp->protocol & ~0x8000) == proto) {
diff -urN ppp.old/pppd/options.c ppp.dev/pppd/options.c
--- ppp.old/pppd/options.c 2006-03-18 15:58:00.000000000 +0100
+++ ppp.dev/pppd/options.c 2006-03-18 18:05:58.000000000 +0100
@@ -57,14 +57,7 @@
#ifdef PPP_FILTER
#include <pcap.h>
-/*
- * DLT_PPP_WITH_DIRECTION is in current libpcap cvs, and should be in
- * libpcap-0.8.4. Until that is released, use DLT_PPP - but that means
- * we lose the inbound and outbound qualifiers.
- */
-#ifndef DLT_PPP_WITH_DIRECTION
-#define DLT_PPP_WITH_DIRECTION DLT_PPP
-#endif
+#include <pcap-bpf.h>
#endif
#include "pppd.h"
@@ -155,6 +148,13 @@
static int loadplugin __P((char **));
#endif
+#ifdef PPP_PRECOMPILED_FILTER
+#include "pcap_pcc.h"
+static int setprecompiledpassfilter __P((char **));
+static int setprecompiledactivefilter __P((char **));
+#undef PPP_FILTER
+#endif
+
#ifdef PPP_FILTER
static int setpassfilter __P((char **));
static int setactivefilter __P((char **));
@@ -312,6 +312,14 @@
"set filter for active pkts", OPT_PRIO },
#endif
+#ifdef PPP_PRECOMPILED_FILTER
+ { "precompiled-pass-filter", 1, setprecompiledpassfilter,
+ "set precompiled filter for packets to pass", OPT_PRIO },
+
+ { "precompiled-active-filter", 1, setprecompiledactivefilter,
+ "set precompiled filter for active pkts", OPT_PRIO },
+#endif
+
#ifdef MAXOCTETS
{ "maxoctets", o_int, &maxoctets,
"Set connection traffic limit",
@@ -1447,6 +1455,29 @@
return ok;
}
+#ifdef PPP_PRECOMPILED_FILTER
+/*
+ * setprecompiledpassfilter - Set the pass filter for packets using a
+ * precompiled expression
+ */
+static int
+setprecompiledpassfilter(argv)
+ char **argv;
+{
+ return pcap_pre_compiled (*argv, &pass_filter);
+}
+
+/*
+ * setactivefilter - Set the active filter for packets
+ */
+static int
+setprecompiledactivefilter(argv)
+ char **argv;
+{
+ return pcap_pre_compiled (*argv, &active_filter);
+}
+#endif
+
#ifdef PPP_FILTER
/*
* setpassfilter - Set the pass filter for packets
@@ -1458,7 +1489,7 @@
pcap_t *pc;
int ret = 0;
- pc = pcap_open_dead(DLT_PPP_WITH_DIRECTION, 65535);
+ pc = pcap_open_dead(DLT_PPP_PPPD, 65535);
if (pcap_compile(pc, &pass_filter, *argv, 1, netmask) == -1) {
option_error("error in pass-filter expression: %s\n",
pcap_geterr(pc));
@@ -1479,7 +1510,7 @@
pcap_t *pc;
int ret = 0;
- pc = pcap_open_dead(DLT_PPP_WITH_DIRECTION, 65535);
+ pc = pcap_open_dead(DLT_PPP_PPPD, 65535);
if (pcap_compile(pc, &active_filter, *argv, 1, netmask) == -1) {
option_error("error in active-filter expression: %s\n",
pcap_geterr(pc));
diff -urN ppp.old/pppd/pcap_pcc.c ppp.dev/pppd/pcap_pcc.c
--- ppp.old/pppd/pcap_pcc.c 1970-01-01 01:00:00.000000000 +0100
+++ ppp.dev/pppd/pcap_pcc.c 2006-03-18 16:51:31.000000000 +0100
@@ -0,0 +1,74 @@
+#include <pcap.h>
+#include <pcap-bpf.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include "pppd.h"
+
+int pcap_pre_compiled (char * fname, struct bpf_program *p)
+{
+ char buf[128];
+ int line = 0, size = 0, index=0, ret=1;
+ FILE *f = fopen (fname, "r");
+ if (!f)
+ {
+ option_error("error opening precompiled active-filter '%s': %s",
+ fname, strerror (errno));
+ return 0;
+ }
+ while (fgets (buf, 127, f))
+ {
+ line++;
+ if (*buf == '#')
+ continue;
+ if (size)
+ {
+ /*
+ struct bpf_insn {
+ u_short code;
+ u_char jt;
+ u_char jf;
+ bpf_int32 k;
+ }
+ */
+ struct bpf_insn * insn = & p->bf_insns[index];
+ unsigned code, jt, jf, k;
+ if (sscanf (buf, "%u %u %u %u", &code, &jt, &jf, &k) != 4)
+ {
+ goto err;
+ }
+ insn->code = code;
+ insn->jt = jt;
+ insn->jf = jf;
+ insn->k = k;
+ index++;
+ }
+ else
+ {
+ if (sscanf (buf, "%u", &size) != 1)
+ {
+ goto err;
+ }
+ p->bf_len = size;
+ p->bf_insns = (struct bpf_insn *)
+ malloc (size * sizeof (struct bpf_insn));
+ }
+ }
+ if (size != index)
+ {
+ option_error("error in precompiled active-filter,"
+ " expected %d expressions, got %dn",
+ size, index);
+ ret = 0;
+ }
+ fclose(f);
+ return ret;
+
+err:
+ option_error("error in precompiled active-filter"
+ " expression line %s:%d (wrong size)\n",
+ fname, line);
+ fclose (f);
+ return 0;
+}
diff -urN ppp.old/pppd/pcap_pcc.h ppp.dev/pppd/pcap_pcc.h
--- ppp.old/pppd/pcap_pcc.h 1970-01-01 01:00:00.000000000 +0100
+++ ppp.dev/pppd/pcap_pcc.h 2006-03-18 15:59:14.000000000 +0100
@@ -0,0 +1,7 @@
+#ifndef PCAP_PCC_H
+#define PCAP_PCC_H
+
+#include <pcap.h>
+
+int pcap_pre_compiled (char * fname, struct bpf_program *p);
+#endif /* PCAP_PCC_H */
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