diff options
Diffstat (limited to 'libdde_linux26/examples/ne2k/arping.c')
| -rw-r--r-- | libdde_linux26/examples/ne2k/arping.c | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/libdde_linux26/examples/ne2k/arping.c b/libdde_linux26/examples/ne2k/arping.c new file mode 100644 index 00000000..18876806 --- /dev/null +++ b/libdde_linux26/examples/ne2k/arping.c @@ -0,0 +1,185 @@ +/**************************************************************** + * (c) 2007 Technische Universitaet Dresden * + * This file is part of DROPS, which is distributed under the * + * terms of the GNU General Public License 2. Please see the * + * COPYING file for details. * + ****************************************************************/ + +#include <l4/log/l4log.h> +#include <l4/util/util.h> +#include <l4/util/l4_macros.h> +#include <l4/sys/ipc.h> + +#include <linux/netdevice.h> +#include <linux/if_ether.h> + +#include "arping.h" + +#define PROT_ICMP 1 +#define ICMP_REPLY 0 +#define ICMP_REQ 8 +#define ETH_ALEN 6 + +/* configuration */ +int arping_verbose = 0; // verbose + +#define VERBOSE_LOG(fmt, ...) \ + do { \ + if (arping_verbose) printk(fmt, ##__VA_ARGS__); \ + } while (0); + +char LOG_tag[9] = "arping"; +l4_ssize_t l4libc_heapsize = 32 * 1024; + +static unsigned char broadcast_mac[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; +static int exit_somewhen = 0; + + +struct ethernet_hdr +{ + unsigned char dest[6]; + unsigned char src[6]; + unsigned char type[2]; +}; + + +struct ip_hdr +{ + char version_length; + char type; + l4_int16_t length; + l4_int16_t id; + l4_int16_t flags_offset; + char ttl; + char protocol; + l4_int16_t checksum; + l4_int32_t src_ip; + l4_int32_t dest_ip; +}; + + +struct icmp_hdr +{ + char type; + char code; + l4_uint16_t checksum; + l4_uint16_t id; + l4_uint16_t seq_num; +}; + + +static int handle_icmp_packet(struct sk_buff *skb); +static int handle_icmp_packet(struct sk_buff *skb) +{ + char *data = skb->data; + struct ethernet_hdr *eth = NULL; + struct ethernet_hdr *e = NULL; + struct ip_hdr *ip = NULL; + struct ip_hdr *iphdr = NULL; + struct icmp_hdr *icmp = NULL; + struct icmp_hdr *icmp2 = NULL; + int ver, len; + struct sk_buff *snd_skb = NULL; + + eth = (struct ethernet_hdr *)data; + VERBOSE_LOG("dest mac = %02x:%02x:%02x:%02x:%02x:%02x\n", + eth->dest[0], eth->dest[1], eth->dest[2], + eth->dest[3], eth->dest[4], eth->dest[5]); + VERBOSE_LOG("src mac = %02x:%02x:%02x:%02x:%02x:%02x\n", + eth->src[0], eth->src[1], eth->src[2], + eth->src[3], eth->src[4], eth->src[5]); + VERBOSE_LOG("type field = %02x%02x\n", eth->type[0], eth->type[1]); + if (eth->type[0] != 0x08 || eth->type[1] != 0x00) { + printk("unknown ethernet packet type!\n"); + return -1; + } + + ip = (struct ip_hdr *)(data + sizeof(struct ethernet_hdr)); + VERBOSE_LOG("protocol = %02x (2x?)\n", ip->protocol, PROT_ICMP); + if (ip->protocol != PROT_ICMP) + { + printk("Unknown packet type.\n"); + return -1; + } + + VERBOSE_LOG("ICMP packet!\n"); + ver = ip->version_length >> 4; + len = ip->version_length & 0x0F; + VERBOSE_LOG("IP version = %d, length = %d\n", ver, len); + + VERBOSE_LOG("src IP: "NIPQUAD_FMT"\n", NIPQUAD(ip->src_ip)); + VERBOSE_LOG("dest IP: "NIPQUAD_FMT"\n", NIPQUAD(ip->dest_ip)); + + icmp = (struct icmp_hdr *)(data + sizeof(struct ethernet_hdr) + + sizeof(struct ip_hdr)); + + if (icmp->type != ICMP_REQ) + { + printk("This is no ICMP request.\n"); + return -1; + } + VERBOSE_LOG("Hey this is an ICMP request just for me. :)\n"); + VERBOSE_LOG("ICMP type : %d\n", icmp->type); + VERBOSE_LOG("ICMP code : %d\n", icmp->code); + VERBOSE_LOG("ICMP seq : %d\n", ntohs(icmp->seq_num)); + + snd_skb = alloc_skb(skb->len + skb->dev->hard_header_len, GFP_KERNEL); + memcpy(snd_skb->data, skb->data, skb->len); + + e = (struct ethernet_hdr *)snd_skb->data; + memcpy(e->src, eth->dest, ETH_ALEN); + memcpy(e->dest, eth->src, ETH_ALEN); + VERBOSE_LOG("dest mac = %02x:%02x:%02x:%02x:%02x:%02x\n", + e->dest[0], e->dest[1], e->dest[2], + e->dest[3], e->dest[4], e->dest[5]); + VERBOSE_LOG("src mac = %02x:%02x:%02x:%02x:%02x:%02x\n", + e->src[0], e->src[1], e->src[2], + e->src[3], e->src[4], e->src[5]); + e->type[0] = 0x08; + e->type[1] = 0x00; + + iphdr = (struct ip_hdr *)(snd_skb->data + sizeof(struct ethernet_hdr)); + *iphdr = *ip; + // also switch src and dest + iphdr->src_ip = ip->dest_ip; + iphdr->dest_ip = ip->src_ip; + VERBOSE_LOG("src IP: "NIPQUAD_FMT"\n", NIPQUAD(iphdr->src_ip)); + VERBOSE_LOG("dest IP: "NIPQUAD_FMT"\n", NIPQUAD(iphdr->dest_ip)); + + icmp2 = (struct icmp_hdr *)(snd_skb->data + sizeof(struct ethernet_hdr) + + sizeof(struct ip_hdr)); + *icmp2 = *icmp; + icmp2->type = ICMP_REPLY; + + snd_skb->dev = skb->dev; + snd_skb->len = skb->len; + + VERBOSE_LOG("sending reply\n"); + skb->dev->hard_start_xmit(snd_skb, skb->dev); + VERBOSE_LOG("done\n"); + + return 0; +} + +ddekit_sem_t *arping_semaphore = NULL; +struct arping_elem *arping_list = NULL; + +int arping(void) +{ + arping_semaphore = ddekit_sem_init(0); + + while(1) + { + ddekit_sem_down(arping_semaphore); + struct arping_elem *elem = arping_list; + arping_list = arping_list->next; + + /* parse packet */ + int err = handle_icmp_packet(elem->skb); + VERBOSE_LOG("handle_icmp_packet: %d\n", err); + + kfree_skb(elem->skb); + kfree(elem); + } +} + |