/* * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) * Licensed under the GPL. */ #include <errno.h> #include <pcap.h> #include <string.h> #include <asm/types.h> #include "net_user.h" #include "pcap_user.h" #include "kern_constants.h" #include "um_malloc.h" #include "user.h" #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, ETH_MAX_PACKET + ETH_HEADER_OTHER, 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 = uml_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)); goto out; } 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)); goto out; } } return PCAP_FD(pri->pcap); out: kfree(pri->compiled); return -EIO; } 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, .add_address = NULL, .delete_address = NULL, .mtu = ETH_MAX_PACKET, .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER, };