diff options
Diffstat (limited to 'contrib/wpa/src/l2_packet/l2_packet_pcap.c')
| -rw-r--r-- | contrib/wpa/src/l2_packet/l2_packet_pcap.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/contrib/wpa/src/l2_packet/l2_packet_pcap.c b/contrib/wpa/src/l2_packet/l2_packet_pcap.c new file mode 100644 index 000000000000..c2b17fcf809c --- /dev/null +++ b/contrib/wpa/src/l2_packet/l2_packet_pcap.c @@ -0,0 +1,400 @@ +/* + * WPA Supplicant - Layer2 packet handling with libpcap/libdnet and WinPcap + * Copyright (c) 2003-2006, Jouni Malinen <j@w1.fi> + * + * This software may be distributed under the terms of the BSD license. + * See README for more details. + */ + +#include "includes.h" +#ifndef CONFIG_NATIVE_WINDOWS +#include <sys/ioctl.h> +#endif /* CONFIG_NATIVE_WINDOWS */ +#include <pcap.h> +#ifndef CONFIG_WINPCAP +#include <dnet.h> +#endif /* CONFIG_WINPCAP */ + +#include "common.h" +#include "eloop.h" +#include "l2_packet.h" + + +static const u8 pae_group_addr[ETH_ALEN] = +{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x03 }; + +struct l2_packet_data { + pcap_t *pcap; +#ifdef CONFIG_WINPCAP + unsigned int num_fast_poll; +#else /* CONFIG_WINPCAP */ + eth_t *eth; +#endif /* CONFIG_WINPCAP */ + char ifname[100]; + u8 own_addr[ETH_ALEN]; + void (*rx_callback)(void *ctx, const u8 *src_addr, + const u8 *buf, size_t len); + void *rx_callback_ctx; + int l2_hdr; /* whether to include layer 2 (Ethernet) header in calls + * to rx_callback */ +}; + + +int l2_packet_get_own_addr(struct l2_packet_data *l2, u8 *addr) +{ + os_memcpy(addr, l2->own_addr, ETH_ALEN); + return 0; +} + + +#ifndef CONFIG_WINPCAP +static int l2_packet_init_libdnet(struct l2_packet_data *l2) +{ + eth_addr_t own_addr; + + l2->eth = eth_open(l2->ifname); + if (!l2->eth) { + wpa_printf(MSG_ERROR, + "Failed to open interface '%s' - eth_open: %s", + l2->ifname, strerror(errno)); + return -1; + } + + if (eth_get(l2->eth, &own_addr) < 0) { + wpa_printf(MSG_ERROR, + "Failed to get own hw address from interface '%s' - eth_get: %s", + l2->ifname, strerror(errno)); + eth_close(l2->eth); + l2->eth = NULL; + return -1; + } + os_memcpy(l2->own_addr, own_addr.data, ETH_ALEN); + + return 0; +} +#endif /* CONFIG_WINPCAP */ + + +int l2_packet_send(struct l2_packet_data *l2, const u8 *dst_addr, u16 proto, + const u8 *buf, size_t len) +{ + int ret; + struct l2_ethhdr *eth; + + if (l2 == NULL) + return -1; + + if (l2->l2_hdr) { +#ifdef CONFIG_WINPCAP + ret = pcap_sendpacket(l2->pcap, buf, len); +#else /* CONFIG_WINPCAP */ + ret = eth_send(l2->eth, buf, len); +#endif /* CONFIG_WINPCAP */ + } else { + size_t mlen = sizeof(*eth) + len; + eth = os_malloc(mlen); + if (eth == NULL) + return -1; + + os_memcpy(eth->h_dest, dst_addr, ETH_ALEN); + os_memcpy(eth->h_source, l2->own_addr, ETH_ALEN); + eth->h_proto = htons(proto); + os_memcpy(eth + 1, buf, len); + +#ifdef CONFIG_WINPCAP + ret = pcap_sendpacket(l2->pcap, (u8 *) eth, mlen); +#else /* CONFIG_WINPCAP */ + ret = eth_send(l2->eth, (u8 *) eth, mlen); +#endif /* CONFIG_WINPCAP */ + + os_free(eth); + } + + return ret; +} + + +#ifndef CONFIG_WINPCAP +static void l2_packet_receive(int sock, void *eloop_ctx, void *sock_ctx) +{ + struct l2_packet_data *l2 = eloop_ctx; + pcap_t *pcap = sock_ctx; + struct pcap_pkthdr hdr; + const u_char *packet; + struct l2_ethhdr *ethhdr; + unsigned char *buf; + size_t len; + + packet = pcap_next(pcap, &hdr); + + if (!l2->rx_callback || !packet || hdr.caplen < sizeof(*ethhdr)) + return; + + ethhdr = (struct l2_ethhdr *) packet; + if (l2->l2_hdr) { + buf = (unsigned char *) ethhdr; + len = hdr.caplen; + } else { + buf = (unsigned char *) (ethhdr + 1); + len = hdr.caplen - sizeof(*ethhdr); + } + l2->rx_callback(l2->rx_callback_ctx, ethhdr->h_source, buf, len); +} +#endif /* CONFIG_WINPCAP */ + + +#ifdef CONFIG_WINPCAP +static void l2_packet_receive_cb(u_char *user, const struct pcap_pkthdr *hdr, + const u_char *pkt_data) +{ + struct l2_packet_data *l2 = (struct l2_packet_data *) user; + struct l2_ethhdr *ethhdr; + unsigned char *buf; + size_t len; + + if (!l2->rx_callback || !pkt_data || hdr->caplen < sizeof(*ethhdr)) + return; + + ethhdr = (struct l2_ethhdr *) pkt_data; + if (l2->l2_hdr) { + buf = (unsigned char *) ethhdr; + len = hdr->caplen; + } else { + buf = (unsigned char *) (ethhdr + 1); + len = hdr->caplen - sizeof(*ethhdr); + } + l2->rx_callback(l2->rx_callback_ctx, ethhdr->h_source, buf, len); + /* + * Use shorter poll interval for 3 seconds to reduce latency during key + * handshake. + */ + l2->num_fast_poll = 3 * 50; +} + + +static void l2_packet_receive_timeout(void *eloop_ctx, void *timeout_ctx) +{ + struct l2_packet_data *l2 = eloop_ctx; + pcap_t *pcap = timeout_ctx; + int timeout; + + if (l2->num_fast_poll > 0) { + timeout = 20000; + l2->num_fast_poll--; + } else + timeout = 100000; + + /* Register new timeout before calling l2_packet_receive() since + * receive handler may free this l2_packet instance (which will + * cancel this timeout). */ + eloop_register_timeout(0, timeout, l2_packet_receive_timeout, + l2, pcap); + pcap_dispatch(pcap, 10, l2_packet_receive_cb, (u_char *) l2); +} +#endif /* CONFIG_WINPCAP */ + + +static int l2_packet_init_libpcap(struct l2_packet_data *l2, + unsigned short protocol) +{ + bpf_u_int32 pcap_maskp, pcap_netp; + char pcap_filter[200], pcap_err[PCAP_ERRBUF_SIZE]; + struct bpf_program pcap_fp; + +#ifdef CONFIG_WINPCAP + char ifname[128]; + os_snprintf(ifname, sizeof(ifname), "\\Device\\NPF_%s", l2->ifname); + pcap_lookupnet(ifname, &pcap_netp, &pcap_maskp, pcap_err); + l2->pcap = pcap_open_live(ifname, 2500, 0, 10, pcap_err); + if (l2->pcap == NULL) { + fprintf(stderr, "pcap_open_live: %s\n", pcap_err); + fprintf(stderr, "ifname='%s'\n", ifname); + return -1; + } + if (pcap_setnonblock(l2->pcap, 1, pcap_err) < 0) + fprintf(stderr, "pcap_setnonblock: %s\n", + pcap_geterr(l2->pcap)); +#else /* CONFIG_WINPCAP */ + pcap_lookupnet(l2->ifname, &pcap_netp, &pcap_maskp, pcap_err); + l2->pcap = pcap_open_live(l2->ifname, 2500, 0, 10, pcap_err); + if (l2->pcap == NULL) { + fprintf(stderr, "pcap_open_live: %s\n", pcap_err); + fprintf(stderr, "ifname='%s'\n", l2->ifname); + return -1; + } + if (pcap_datalink(l2->pcap) != DLT_EN10MB && + pcap_set_datalink(l2->pcap, DLT_EN10MB) < 0) { + fprintf(stderr, "pcap_set_datalink(DLT_EN10MB): %s\n", + pcap_geterr(l2->pcap)); + return -1; + } +#endif /* CONFIG_WINPCAP */ + os_snprintf(pcap_filter, sizeof(pcap_filter), + "not ether src " MACSTR " and " + "( ether dst " MACSTR " or ether dst " MACSTR " ) and " + "ether proto 0x%x", + MAC2STR(l2->own_addr), /* do not receive own packets */ + MAC2STR(l2->own_addr), MAC2STR(pae_group_addr), + protocol); + if (pcap_compile(l2->pcap, &pcap_fp, pcap_filter, 1, pcap_netp) < 0) { + fprintf(stderr, "pcap_compile: %s\n", pcap_geterr(l2->pcap)); + return -1; + } + + if (pcap_setfilter(l2->pcap, &pcap_fp) < 0) { + fprintf(stderr, "pcap_setfilter: %s\n", pcap_geterr(l2->pcap)); + return -1; + } + + pcap_freecode(&pcap_fp); +#ifdef BIOCIMMEDIATE + /* + * When libpcap uses BPF we must enable "immediate mode" to + * receive frames right away; otherwise the system may + * buffer them for us. + */ + { + unsigned int on = 1; + if (ioctl(pcap_fileno(l2->pcap), BIOCIMMEDIATE, &on) < 0) { + fprintf(stderr, "%s: cannot enable immediate mode on " + "interface %s: %s\n", + __func__, l2->ifname, strerror(errno)); + /* XXX should we fail? */ + } + } +#endif /* BIOCIMMEDIATE */ + +#ifdef CONFIG_WINPCAP + eloop_register_timeout(0, 100000, l2_packet_receive_timeout, + l2, l2->pcap); +#else /* CONFIG_WINPCAP */ + eloop_register_read_sock(pcap_get_selectable_fd(l2->pcap), + l2_packet_receive, l2, l2->pcap); +#endif /* CONFIG_WINPCAP */ + + return 0; +} + + +struct l2_packet_data * l2_packet_init( + const char *ifname, const u8 *own_addr, unsigned short protocol, + void (*rx_callback)(void *ctx, const u8 *src_addr, + const u8 *buf, size_t len), + void *rx_callback_ctx, int l2_hdr) +{ + struct l2_packet_data *l2; + + l2 = os_zalloc(sizeof(struct l2_packet_data)); + if (l2 == NULL) + return NULL; + os_strlcpy(l2->ifname, ifname, sizeof(l2->ifname)); + l2->rx_callback = rx_callback; + l2->rx_callback_ctx = rx_callback_ctx; + l2->l2_hdr = l2_hdr; + +#ifdef CONFIG_WINPCAP + if (own_addr) + os_memcpy(l2->own_addr, own_addr, ETH_ALEN); +#else /* CONFIG_WINPCAP */ + if (l2_packet_init_libdnet(l2)) + return NULL; +#endif /* CONFIG_WINPCAP */ + + if (l2_packet_init_libpcap(l2, protocol)) { +#ifndef CONFIG_WINPCAP + eth_close(l2->eth); +#endif /* CONFIG_WINPCAP */ + os_free(l2); + return NULL; + } + + return l2; +} + + +struct l2_packet_data * l2_packet_init_bridge( + const char *br_ifname, const char *ifname, const u8 *own_addr, + unsigned short protocol, + void (*rx_callback)(void *ctx, const u8 *src_addr, + const u8 *buf, size_t len), + void *rx_callback_ctx, int l2_hdr) +{ + return l2_packet_init(br_ifname, own_addr, protocol, rx_callback, + rx_callback_ctx, l2_hdr); +} + + +void l2_packet_deinit(struct l2_packet_data *l2) +{ + if (l2 == NULL) + return; + +#ifdef CONFIG_WINPCAP + eloop_cancel_timeout(l2_packet_receive_timeout, l2, l2->pcap); +#else /* CONFIG_WINPCAP */ + if (l2->eth) + eth_close(l2->eth); + eloop_unregister_read_sock(pcap_get_selectable_fd(l2->pcap)); +#endif /* CONFIG_WINPCAP */ + if (l2->pcap) + pcap_close(l2->pcap); + os_free(l2); +} + + +int l2_packet_get_ip_addr(struct l2_packet_data *l2, char *buf, size_t len) +{ + pcap_if_t *devs, *dev; + struct pcap_addr *addr; + struct sockaddr_in *saddr; + int found = 0; + char err[PCAP_ERRBUF_SIZE + 1]; + + if (pcap_findalldevs(&devs, err) < 0) { + wpa_printf(MSG_DEBUG, "pcap_findalldevs: %s\n", err); + return -1; + } + + for (dev = devs; dev && !found; dev = dev->next) { + if (os_strcmp(dev->name, l2->ifname) != 0) + continue; + + addr = dev->addresses; + while (addr) { + saddr = (struct sockaddr_in *) addr->addr; + if (saddr && saddr->sin_family == AF_INET) { + os_strlcpy(buf, inet_ntoa(saddr->sin_addr), + len); + found = 1; + break; + } + addr = addr->next; + } + } + + pcap_freealldevs(devs); + + return found ? 0 : -1; +} + + +void l2_packet_notify_auth_start(struct l2_packet_data *l2) +{ +#ifdef CONFIG_WINPCAP + /* + * Use shorter poll interval for 3 seconds to reduce latency during key + * handshake. + */ + l2->num_fast_poll = 3 * 50; + eloop_cancel_timeout(l2_packet_receive_timeout, l2, l2->pcap); + eloop_register_timeout(0, 10000, l2_packet_receive_timeout, + l2, l2->pcap); +#endif /* CONFIG_WINPCAP */ +} + + +int l2_packet_set_packet_filter(struct l2_packet_data *l2, + enum l2_packet_filter_type type) +{ + return -1; +} |