l2_packet_linux.c
Go to the documentation of this file.
00001 /*
00002  * WPA Supplicant - Layer2 packet handling with Linux packet sockets
00003  * Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
00004  *
00005  * This program is free software; you can redistribute it and/or modify
00006  * it under the terms of the GNU General Public License version 2 as
00007  * published by the Free Software Foundation.
00008  *
00009  * Alternatively, this software may be distributed under the terms of BSD
00010  * license.
00011  *
00012  * See README and COPYING for more details.
00013  */
00014 
00015 #include "includes.h"
00016 #include <sys/ioctl.h>
00017 #include <netpacket/packet.h>
00018 #include <net/if.h>
00019 
00020 #include "common.h"
00021 #include "eloop.h"
00022 #include "l2_packet.h"
00023 
00024 
00025 struct l2_packet_data {
00026         int fd; /* packet socket for EAPOL frames */
00027         char ifname[IFNAMSIZ + 1];
00028         int ifindex;
00029         u8 own_addr[ETH_ALEN];
00030         void (*rx_callback)(void *ctx, const u8 *src_addr,
00031                             const u8 *buf, size_t len);
00032         void *rx_callback_ctx;
00033         int l2_hdr; /* whether to include layer 2 (Ethernet) header data
00034                      * buffers */
00035 };
00036 
00037 
00038 int l2_packet_get_own_addr(struct l2_packet_data *l2, u8 *addr)
00039 {
00040         os_memcpy(addr, l2->own_addr, ETH_ALEN);
00041         return 0;
00042 }
00043 
00044 
00045 int l2_packet_send(struct l2_packet_data *l2, const u8 *dst_addr, u16 proto,
00046                    const u8 *buf, size_t len)
00047 {
00048         int ret;
00049         if (l2 == NULL)
00050                 return -1;
00051         if (l2->l2_hdr) {
00052                 ret = send(l2->fd, buf, len, 0);
00053                 if (ret < 0)
00054                         perror("l2_packet_send - send");
00055         } else {
00056                 struct sockaddr_ll ll;
00057                 os_memset(&ll, 0, sizeof(ll));
00058                 ll.sll_family = AF_PACKET;
00059                 ll.sll_ifindex = l2->ifindex;
00060                 ll.sll_protocol = htons(proto);
00061                 ll.sll_halen = ETH_ALEN;
00062                 os_memcpy(ll.sll_addr, dst_addr, ETH_ALEN);
00063                 ret = sendto(l2->fd, buf, len, 0, (struct sockaddr *) &ll,
00064                              sizeof(ll));
00065                 if (ret < 0)
00066                         perror("l2_packet_send - sendto");
00067         }
00068         return ret;
00069 }
00070 
00071 
00072 static void l2_packet_receive(int sock, void *eloop_ctx, void *sock_ctx)
00073 {
00074         struct l2_packet_data *l2 = eloop_ctx;
00075         u8 buf[2300];
00076         int res;
00077         struct sockaddr_ll ll;
00078         socklen_t fromlen;
00079 
00080         os_memset(&ll, 0, sizeof(ll));
00081         fromlen = sizeof(ll);
00082         res = recvfrom(sock, buf, sizeof(buf), 0, (struct sockaddr *) &ll,
00083                        &fromlen);
00084         if (res < 0) {
00085                 perror("l2_packet_receive - recvfrom");
00086                 return;
00087         }
00088 
00089         l2->rx_callback(l2->rx_callback_ctx, ll.sll_addr, buf, res);
00090 }
00091 
00092 
00093 struct l2_packet_data * l2_packet_init(
00094         const char *ifname, const u8 *own_addr, unsigned short protocol,
00095         void (*rx_callback)(void *ctx, const u8 *src_addr,
00096                             const u8 *buf, size_t len),
00097         void *rx_callback_ctx, int l2_hdr)
00098 {
00099         struct l2_packet_data *l2;
00100         struct ifreq ifr;
00101         struct sockaddr_ll ll;
00102 
00103         l2 = os_zalloc(sizeof(struct l2_packet_data));
00104         if (l2 == NULL)
00105                 return NULL;
00106         os_strlcpy(l2->ifname, ifname, sizeof(l2->ifname));
00107         l2->rx_callback = rx_callback;
00108         l2->rx_callback_ctx = rx_callback_ctx;
00109         l2->l2_hdr = l2_hdr;
00110 
00111         l2->fd = socket(PF_PACKET, l2_hdr ? SOCK_RAW : SOCK_DGRAM,
00112                         htons(protocol));
00113         if (l2->fd < 0) {
00114                 perror("socket(PF_PACKET)");
00115                 os_free(l2);
00116                 return NULL;
00117         }
00118         os_memset(&ifr, 0, sizeof(ifr));
00119         os_strlcpy(ifr.ifr_name, l2->ifname, sizeof(ifr.ifr_name));
00120         if (ioctl(l2->fd, SIOCGIFINDEX, &ifr) < 0) {
00121                 perror("ioctl[SIOCGIFINDEX]");
00122                 close(l2->fd);
00123                 os_free(l2);
00124                 return NULL;
00125         }
00126         l2->ifindex = ifr.ifr_ifindex;
00127 
00128         os_memset(&ll, 0, sizeof(ll));
00129         ll.sll_family = PF_PACKET;
00130         ll.sll_ifindex = ifr.ifr_ifindex;
00131         ll.sll_protocol = htons(protocol);
00132         if (bind(l2->fd, (struct sockaddr *) &ll, sizeof(ll)) < 0) {
00133                 perror("bind[PF_PACKET]");
00134                 close(l2->fd);
00135                 os_free(l2);
00136                 return NULL;
00137         }
00138 
00139         if (ioctl(l2->fd, SIOCGIFHWADDR, &ifr) < 0) {
00140                 perror("ioctl[SIOCGIFHWADDR]");
00141                 close(l2->fd);
00142                 os_free(l2);
00143                 return NULL;
00144         }
00145         os_memcpy(l2->own_addr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
00146 
00147         eloop_register_read_sock(l2->fd, l2_packet_receive, l2, NULL);
00148 
00149         return l2;
00150 }
00151 
00152 
00153 void l2_packet_deinit(struct l2_packet_data *l2)
00154 {
00155         if (l2 == NULL)
00156                 return;
00157 
00158         if (l2->fd >= 0) {
00159                 eloop_unregister_read_sock(l2->fd);
00160                 close(l2->fd);
00161         }
00162                 
00163         os_free(l2);
00164 }
00165 
00166 
00167 int l2_packet_get_ip_addr(struct l2_packet_data *l2, char *buf, size_t len)
00168 {
00169         int s;
00170         struct ifreq ifr;
00171         struct sockaddr_in *saddr;
00172         size_t res;
00173 
00174         s = socket(PF_INET, SOCK_DGRAM, 0);
00175         if (s < 0) {
00176                 perror("socket");
00177                 return -1;
00178         }
00179         os_memset(&ifr, 0, sizeof(ifr));
00180         os_strlcpy(ifr.ifr_name, l2->ifname, sizeof(ifr.ifr_name));
00181         if (ioctl(s, SIOCGIFADDR, &ifr) < 0) {
00182                 if (errno != EADDRNOTAVAIL)
00183                         perror("ioctl[SIOCGIFADDR]");
00184                 close(s);
00185                 return -1;
00186         }
00187         close(s);
00188         saddr = aliasing_hide_typecast(&ifr.ifr_addr, struct sockaddr_in);
00189         if (saddr->sin_family != AF_INET)
00190                 return -1;
00191         res = os_strlcpy(buf, inet_ntoa(saddr->sin_addr), len);
00192         if (res >= len)
00193                 return -1;
00194         return 0;
00195 }
00196 
00197 
00198 void l2_packet_notify_auth_start(struct l2_packet_data *l2)
00199 {
00200 }


wpa_supplicant_node
Author(s): Package maintained by Blaise Gassend
autogenerated on Thu Jan 2 2014 11:25:14