From: hackbard <hackbard>
Date: Tue, 12 Nov 2002 16:05:02 +0000 (+0000)
Subject: fixed and cached offsets - 1st try
X-Git-Url: https://hackdaworld.org/gitweb/?p=my-code%2Fhdw-sniff.git;a=commitdiff_plain;h=0819f943f6d301332559b998e67b8fbf13975f15

fixed and cached offsets - 1st try
---

diff --git a/hdw-sniff.c b/hdw-sniff.c
index 54e40db..94830b7 100644
--- a/hdw-sniff.c
+++ b/hdw-sniff.c
@@ -103,7 +103,7 @@ int main(int argc, char *argv[]) {
 		FD_ZERO(&pcap_fd_set);
 		FD_SET(pcap_fd,&pcap_fd_set);
 		fd_set_tv.tv_sec=0;
-		fd_set_tv.tv_usec=500000;
+		fd_set_tv.tv_usec=200000;
 
 		if((select(pcap_fd+1,&pcap_fd_set,NULL,NULL,&fd_set_tv)) && (FD_ISSET(pcap_fd,&pcap_fd_set))) pcap_dispatch(pcap_handle,-1,pcap_process,(u_char *)&my_info_struct);
 		else if((hop_channel(&my_info_struct,foo_fd))==-1) { 
@@ -125,7 +125,13 @@ void pcap_process(u_char *info,const struct pcap_pkthdr *pcap_header,
 	struct ethhdr *e_hdr;
 	struct ip *ip_hdr;
 	struct info_struct *my_info_struct;
-	int i;
+	int i,p_o,w_o,e_o,i_o;
+	
+	/* cache offsets */
+	p_o=sizeof(struct linux_wlan_ng_prism_hdr);
+	w_o=sizeof(struct ieee802_11_hdr);
+	e_o=sizeof(struct ethhdr);
+	i_o=sizeof(struct ip);
 
 	my_info_struct=(struct info_struct *)info;
 	++(my_info_struct->count);
@@ -140,16 +146,17 @@ void pcap_process(u_char *info,const struct pcap_pkthdr *pcap_header,
 	/* prism wlan ng headers */
 	if((my_info_struct->mmode-0x30==1) && 
 		(strncmp(my_info_struct->dev,"wlan",4)==0)) {
-	printf("prism header:\n");
+	printf("prism header: (%d bytes)\n",p_o);
 	prism_hdr=(struct linux_wlan_ng_prism_hdr *)package;
 	printf("message code/length: %d/%d\n",ntohs(prism_hdr->msgcode),
 						ntohs(prism_hdr->msglen));
 	printf("device: %s\n",prism_hdr->devname);
+	/* skip wlan_ng_prism header */
+	// package=package+p_o;
 
 	/* ieee802.11 header */
-	printf("ieee802.11 header:\n");
-	package+=sizeof(struct linux_wlan_ng_prism_hdr);
-	w_hdr=(struct ieee802_11_hdr *)package;
+	printf("ieee802.11 header: (%d bytes)\n",w_o);
+	w_hdr=(struct ieee802_11_hdr *)(package+p_o);
 	
 	printf("debug:\n");
 	for(i=0;i<16;i++) {
@@ -163,13 +170,13 @@ void pcap_process(u_char *info,const struct pcap_pkthdr *pcap_header,
 							"ok":"unknown");
 	// printf("type: 
 	/* skip ieee802.11 header */
-	package=package+sizeof(struct ieee802_11_hdr);
+	// package=package+w_o;
 	}
 
 	/* ieee802.3 */
 	/* ethernet */
 	printf("ethernet:\n");
-	e_hdr=(struct ethhdr *)package;
+	e_hdr=(struct ethhdr *)(package+p_o+w_o);
 	/* what types ? */
 	printf("type = ");
 	printf("%x  ",ntohs(e_hdr->h_proto));
@@ -182,7 +189,7 @@ void pcap_process(u_char *info,const struct pcap_pkthdr *pcap_header,
 		/* IP ? */
 	if(ntohs(e_hdr->h_proto)==ETH_P_IP) {
 		printf("ip protocol: ");
-		ip_hdr=(struct ip *)(package+sizeof(struct ethhdr));
+		ip_hdr=(struct ip *)(package+p_o+w_o+e_o);
 		printf("version = %x ",ntohs(ip_hdr->ip_v));
 		printf("header_length = %x \n",ntohs(ip_hdr->ip_hl));
 		printf("service = %x ",ntohs(ip_hdr->ip_tos));
@@ -196,8 +203,8 @@ void pcap_process(u_char *info,const struct pcap_pkthdr *pcap_header,
 						ntohs(ip_hdr->ip_p));
 		printf("chksum: %x\n",ntohs(ip_hdr->ip_sum));
 	}
-	printf("all_hex_dump:\n");
-	for(i=sizeof(struct ethhdr);i<pcap_header->caplen;i++)
+	printf("all ethernet dump:\n");
+	for(i=p_o+w_o+e_o;i<pcap_header->caplen;i++)
 		printf("%x ",*(package+i));
 	printf("\n");
 }