From e58e6b25c82cc2f76f08b291e14f4e81f4ae1364 Mon Sep 17 00:00:00 2001

From: Guy Harris <guy@alum.mit.edu>

Date: Wed, 5 Nov 2014 11:18:51 -0800

Subject: [PATCH 3/3] More descriptive name for bpf_filter1().

Call it bpf_filter_with_aux_data(), to better indicate what it does.

Also expand some comments and clean up white space a bit.

(cherry picked from 20119d41be224cf9ea821155ad0b267f7e40f234)

Conflicts:

        pcap-linux.c

---

 bpf/net/bpf_filter.c | 7 +++++--

 pcap-linux.c         | 7 +++----

 pcap/bpf.h           | 7 ++++++-

 3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/bpf/net/bpf_filter.c b/bpf/net/bpf_filter.c

index 3409a9b..307f980 100644

--- a/bpf/net/bpf_filter.c

+++ b/bpf/net/bpf_filter.c

@@ -215,11 +215,14 @@ enum {

  * Execute the filter program starting at pc on the packet p

  * wirelen is the length of the original packet

  * buflen is the amount of data present

+ * aux_data is auxiliary data, currently used only when interpreting

+ * filters intended for the Linux kernel in cases where the kernel

+ * rejects the filter; it contains VLAN tag information

  * For the kernel, p is assumed to be a pointer to an mbuf if buflen is 0,

  * in all other cases, p is a pointer to a buffer and buflen is its size.

  */

 u_int

-bpf_filter1(pc, p, wirelen, buflen, aux_data)

+bpf_filter_with_aux_data(pc, p, wirelen, buflen, aux_data)

 	register const struct bpf_insn *pc;

 	register const u_char *p;

 	u_int wirelen;

@@ -579,7 +582,7 @@ bpf_filter(pc, p, wirelen, buflen)

 	u_int wirelen;

 	register u_int buflen;

 {

-	return bpf_filter1(pc, p, wirelen, buflen, NULL);

+	return bpf_filter_with_aux_data(pc, p, wirelen, buflen, NULL);

 }

diff --git a/pcap-linux.c b/pcap-linux.c

index 68e6d05..a370858 100644

--- a/pcap-linux.c

+++ b/pcap-linux.c

@@ -1708,9 +1708,8 @@ pcap_read_packet(pcap_t *handle, pcap_handler callback, u_char *userdata)

 	/* Run the packet filter if not using kernel filter */

 	if (handlep->filter_in_userland && handle->fcode.bf_insns) {

-		if (bpf_filter1(handle->fcode.bf_insns, bp,

-		                packet_len, caplen, &aux_data) == 0)

-		{

+		if (bpf_filter_with_aux_data(handle->fcode.bf_insns, bp,

+		    packet_len, caplen, &aux_data) == 0) {

 			/* rejected by filter */

 			return 0;

 		}

@@ -4282,7 +4281,7 @@ static int pcap_handle_packet_mmap(

                 aux_data.vlan_tag = tp_vlan_tci & 0x0fff;

                 aux_data.vlan_tag_present = tp_vlan_tci_valid;

-                if (bpf_filter1(handle->fcode.bf_insns, bp, tp_len, tp_snaplen, &aux_data) == 0)

+                if (bpf_filter_with_aux_data(handle->fcode.bf_insns, bp, tp_len, tp_snaplen, &aux_data) == 0)

                         return 0;

         }

diff --git a/pcap/bpf.h b/pcap/bpf.h

index 495f326..29efd7e 100644

--- a/pcap/bpf.h

+++ b/pcap/bpf.h

@@ -1320,6 +1320,11 @@ struct bpf_insn {

 	bpf_u_int32 k;

 };

+/*

+ * Auxiliary data, for use when interpreting a filter intended for the

+ * Linux kernel when the kernel rejects the filter (requiring us to

+ * run it in userland).  It contains VLAN tag information.

+ */

 struct bpf_aux_data {

         uint16_t vlan_tag_present;

         uint16_t vlan_tag;

@@ -1334,7 +1339,7 @@ struct bpf_aux_data {

 #if __STDC__ || defined(__cplusplus)

 extern int bpf_validate(const struct bpf_insn *, int);

 extern u_int bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int);

-extern u_int bpf_filter1(const struct bpf_insn *, const u_char *, u_int, u_int, const struct bpf_aux_data *);        

+extern u_int bpf_filter_with_aux_data(const struct bpf_insn *, const u_char *, u_int, u_int, const struct bpf_aux_data *);        

 #else

 extern int bpf_validate();

 extern u_int bpf_filter();

-- 

2.4.3