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/*
* Copyright (C) 2002 Jeff Dike <jdike@karaya.com>
* Licensed under the GPL.
*/
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <pcap.h>
#include <asm/types.h>
#include "net_user.h"
#include "pcap_user.h"
#include "user.h"
#include "um_malloc.h"
#include "kern_constants.h"
#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER)
#define PCAP_FD(p) (*(int *)(p))
static int pcap_user_init(void *data, void *dev)
{
struct pcap_data *pri = data;
pcap_t *p;
char errors[PCAP_ERRBUF_SIZE];
p = pcap_open_live(pri->host_if, MAX_PACKET, pri->promisc, 0, errors);
if(p == NULL){
printk(UM_KERN_ERR "pcap_user_init : pcap_open_live failed - "
"'%s'\n", errors);
return -EINVAL;
}
pri->dev = dev;
pri->pcap = p;
return 0;
}
static int pcap_open(void *data)
{
struct pcap_data *pri = data;
__u32 netmask;
int err;
if(pri->pcap == NULL)
return -ENODEV;
if(pri->filter != NULL){
err = dev_netmask(pri->dev, &netmask);
if(err < 0){
printk(UM_KERN_ERR "pcap_open : dev_netmask failed\n");
return -EIO;
}
pri->compiled = kmalloc(sizeof(struct bpf_program), UM_GFP_KERNEL);
if(pri->compiled == NULL){
printk(UM_KERN_ERR "pcap_open : kmalloc failed\n");
return -ENOMEM;
}
err = pcap_compile(pri->pcap,
(struct bpf_program *) pri->compiled,
pri->filter, pri->optimize, netmask);
if(err < 0){
printk(UM_KERN_ERR "pcap_open : pcap_compile failed - "
"'%s'\n", pcap_geterr(pri->pcap));
return -EIO;
}
err = pcap_setfilter(pri->pcap, pri->compiled);
if(err < 0){
printk(UM_KERN_ERR "pcap_open : pcap_setfilter "
"failed - '%s'\n", pcap_geterr(pri->pcap));
return -EIO;
}
}
return PCAP_FD(pri->pcap);
}
static void pcap_remove(void *data)
{
struct pcap_data *pri = data;
if(pri->compiled != NULL)
pcap_freecode(pri->compiled);
if(pri->pcap != NULL)
pcap_close(pri->pcap);
}
struct pcap_handler_data {
char *buffer;
int len;
};
static void handler(u_char *data, const struct pcap_pkthdr *header,
const u_char *packet)
{
int len;
struct pcap_handler_data *hdata = (struct pcap_handler_data *) data;
len = hdata->len < header->caplen ? hdata->len : header->caplen;
memcpy(hdata->buffer, packet, len);
hdata->len = len;
}
int pcap_user_read(int fd, void *buffer, int len, struct pcap_data *pri)
{
struct pcap_handler_data hdata = ((struct pcap_handler_data)
{ .buffer = buffer,
.len = len });
int n;
n = pcap_dispatch(pri->pcap, 1, handler, (u_char *) &hdata);
if(n < 0){
printk(UM_KERN_ERR "pcap_dispatch failed - %s\n",
pcap_geterr(pri->pcap));
return -EIO;
}
else if(n == 0)
return 0;
return hdata.len;
}
const struct net_user_info pcap_user_info = {
.init = pcap_user_init,
.open = pcap_open,
.close = NULL,
.remove = pcap_remove,
.set_mtu = NULL,
.add_address = NULL,
.delete_address = NULL,
.max_packet = MAX_PACKET - ETH_HEADER_OTHER
};
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