X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;ds=sidebyside;f=src%2Ftransport%2Fgnunet-helper-transport-wlan.c;h=3ad4d64c424dbbf6433b4015d971e47328037e0e;hb=66963559294951161370c50f2430a31d54448f86;hp=363925cad7c9ac2593136720804a206156fe9346;hpb=ffd4fa2b692f7658a018be1fa49c1fad0cfab465;p=oweals%2Fgnunet.git diff --git a/src/transport/gnunet-helper-transport-wlan.c b/src/transport/gnunet-helper-transport-wlan.c index 363925cad..3ad4d64c4 100644 --- a/src/transport/gnunet-helper-transport-wlan.c +++ b/src/transport/gnunet-helper-transport-wlan.c @@ -109,8 +109,7 @@ /* * parts taken from aircrack-ng, parts changend. */ - -#define _GNU_SOURCE +#include "gnunet_config.h" #include #include #include @@ -138,6 +137,14 @@ #include "gnunet_protocols.h" #include "plugin_transport_wlan.h" +/** + * Packet format type for the messages we receive from + * the kernel. This is for Ethernet 10Mbps format (no + * performance information included). + */ +#define ARPHRD_ETHER 1 + + /** * Packet format type for the messages we receive from * the kernel. This is for plain messages (with no @@ -145,6 +152,7 @@ */ #define ARPHRD_IEEE80211 801 + /** * Packet format type for the messages we receive from * the kernel. This is for the PRISM format. @@ -1589,6 +1597,15 @@ linux_read (struct HardwareInfos *dev, case ARPHRD_IEEE80211: n = 0; /* no header */ break; + case ARPHRD_ETHER: + { + if (sizeof (struct GNUNET_TRANSPORT_WLAN_Ieee8023Frame) > caplen) + return 0; /* invalid */ + memcpy (&buf[sizeof (struct GNUNET_TRANSPORT_WLAN_Ieee80211Frame)], + tmpbuf + sizeof (struct GNUNET_TRANSPORT_WLAN_Ieee8023Frame), + caplen - sizeof (struct GNUNET_TRANSPORT_WLAN_Ieee8023Frame) - 4 /* 4 byte FCS */); + return caplen - sizeof (struct GNUNET_TRANSPORT_WLAN_Ieee8023Frame) - 4; + } default: errno = ENOTSUP; /* unsupported format */ return -1; @@ -1652,6 +1669,16 @@ open_device_raw (struct HardwareInfos *dev) IFNAMSIZ, dev->iface, strerror (errno)); return 1; } + if (((ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211) && + (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) && + (ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211_PRISM) && + (ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211_FULL)) ) + { + fprintf (stderr, "Error: interface `%.*s' is not using a supported hardware address family (got %d)\n", + IFNAMSIZ, dev->iface, + ifr.ifr_hwaddr.sa_family); + return 1; + } /* lookup iw mode */ memset (&wrq, 0, sizeof (struct iwreq)); @@ -1663,13 +1690,12 @@ open_device_raw (struct HardwareInfos *dev) wrq.u.mode = IW_MODE_MONITOR; } - if (((ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211) && - (ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211_PRISM) && - (ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211_FULL)) || - (wrq.u.mode != IW_MODE_MONITOR)) + if ( (wrq.u.mode != IW_MODE_MONITOR) && + (wrq.u.mode != IW_MODE_ADHOC) ) { - fprintf (stderr, "Error: interface `%.*s' is not in monitor mode\n", - IFNAMSIZ, dev->iface); + fprintf (stderr, "Error: interface `%.*s' is not in monitor or ad-hoc mode (got %d)\n", + IFNAMSIZ, dev->iface, + wrq.u.mode); return 1; } @@ -1705,7 +1731,8 @@ open_device_raw (struct HardwareInfos *dev) memcpy (&dev->pl_mac, ifr.ifr_hwaddr.sa_data, MAC_ADDR_SIZE); dev->arptype_in = ifr.ifr_hwaddr.sa_family; - if ((ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211) && + if ((ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) && + (ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211) && (ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211_PRISM) && (ifr.ifr_hwaddr.sa_family != ARPHRD_IEEE80211_FULL)) { @@ -1771,6 +1798,12 @@ static int mac_test (const struct GNUNET_TRANSPORT_WLAN_Ieee80211Frame *taIeeeHeader, const struct HardwareInfos *dev) { + static struct GNUNET_TRANSPORT_WLAN_MacAddress all_zeros; + + if ( (0 == memcmp (&taIeeeHeader->addr3, &all_zeros, MAC_ADDR_SIZE)) || + (0 == memcmp (&taIeeeHeader->addr1, &all_zeros, MAC_ADDR_SIZE)) ) + return 0; /* some drivers set no Macs, then assume it is all for us! */ + if (0 != memcmp (&taIeeeHeader->addr3, &mac_bssid_gnunet, MAC_ADDR_SIZE)) return 1; /* not a GNUnet ad-hoc package */ if ( (0 == memcmp (&taIeeeHeader->addr1, &dev->pl_mac, MAC_ADDR_SIZE)) || @@ -1812,6 +1845,7 @@ stdin_send_hw (void *cls, const struct GNUNET_MessageHeader *hdr) struct GNUNET_TRANSPORT_WLAN_Ieee80211Frame *wlanheader; size_t sendsize; struct RadiotapTransmissionHeader rtheader; + struct GNUNET_TRANSPORT_WLAN_Ieee8023Frame etheader; sendsize = ntohs (hdr->size); if ( (sendsize < @@ -1828,21 +1862,41 @@ stdin_send_hw (void *cls, const struct GNUNET_MessageHeader *hdr) exit (1); } header = (const struct GNUNET_TRANSPORT_WLAN_RadiotapSendMessage *) hdr; - rtheader.header.it_version = 0; - rtheader.header.it_pad = 0; - rtheader.header.it_len = GNUNET_htole16 (sizeof (rtheader)); - rtheader.header.it_present = GNUNET_htole16 (IEEE80211_RADIOTAP_OUR_TRANSMISSION_HEADER_MASK); - rtheader.rate = header->rate; - rtheader.pad1 = 0; - rtheader.txflags = GNUNET_htole16 (IEEE80211_RADIOTAP_F_TX_NOACK | IEEE80211_RADIOTAP_F_TX_NOSEQ); - memcpy (write_pout.buf, &rtheader, sizeof (rtheader)); - memcpy (&write_pout.buf[sizeof (rtheader)], &header->frame, sendsize); - wlanheader = (struct GNUNET_TRANSPORT_WLAN_Ieee80211Frame *) &write_pout.buf[sizeof (rtheader)]; - - /* payload contains MAC address, but we don't trust it, so we'll - * overwrite it with OUR MAC address to prevent mischief */ - mac_set (wlanheader, dev); - write_pout.size = sendsize + sizeof (rtheader); + switch (dev->arptype_in) + { + case ARPHRD_IEEE80211_PRISM: + case ARPHRD_IEEE80211_FULL: + case ARPHRD_IEEE80211: + rtheader.header.it_version = 0; + rtheader.header.it_pad = 0; + rtheader.header.it_len = GNUNET_htole16 (sizeof (rtheader)); + rtheader.header.it_present = GNUNET_htole16 (IEEE80211_RADIOTAP_OUR_TRANSMISSION_HEADER_MASK); + rtheader.rate = header->rate; + rtheader.pad1 = 0; + rtheader.txflags = GNUNET_htole16 (IEEE80211_RADIOTAP_F_TX_NOACK | IEEE80211_RADIOTAP_F_TX_NOSEQ); + memcpy (write_pout.buf, &rtheader, sizeof (rtheader)); + memcpy (&write_pout.buf[sizeof (rtheader)], &header->frame, sendsize); + wlanheader = (struct GNUNET_TRANSPORT_WLAN_Ieee80211Frame *) &write_pout.buf[sizeof (rtheader)]; + + /* payload contains MAC address, but we don't trust it, so we'll + * overwrite it with OUR MAC address to prevent mischief */ + mac_set (wlanheader, dev); + write_pout.size = sendsize + sizeof (rtheader); + break; + case ARPHRD_ETHER: + etheader.dst = header->frame.addr1; + /* etheader.src = header->frame.addr2; --- untrusted input */ + etheader.src = dev->pl_mac; + etheader.type = htons (ETH_P_IP); + memcpy (write_pout.buf, ðeader, sizeof (etheader)); + memcpy (&write_pout.buf[sizeof (etheader)], &header[1], sendsize - sizeof (struct GNUNET_TRANSPORT_WLAN_Ieee80211Frame)); + write_pout.size = sendsize - sizeof (struct GNUNET_TRANSPORT_WLAN_Ieee80211Frame) + sizeof (etheader); + break; + default: + fprintf (stderr, + "Unsupported ARPTYPE!\n"); + break; + } } @@ -1867,33 +1921,29 @@ main (int argc, char *argv[]) int stdin_open; struct MessageStreamTokenizer *stdin_mst; int raw_eno; + uid_t uid; - memset (&dev, 0, sizeof (dev)); - dev.fd_raw = socket (PF_PACKET, SOCK_RAW, htons (ETH_P_ALL)); - raw_eno = errno; /* remember for later */ - - /* drop privs */ - { - uid_t uid = getuid (); + /* assert privs so we can modify the firewall rules! */ + uid = getuid (); #ifdef HAVE_SETRESUID - if (0 != setresuid (uid, uid, uid)) - { - fprintf (stderr, "Failed to setresuid: %s\n", strerror (errno)); - if (-1 != dev.fd_raw) - (void) close (dev.fd_raw); - return 1; - } + if (0 != setresuid (uid, 0, 0)) + { + fprintf (stderr, "Failed to setresuid to root: %s\n", strerror (errno)); + return 254; + } #else - if (0 != (setuid (uid) | seteuid (uid))) - { - fprintf (stderr, "Failed to setuid: %s\n", strerror (errno)); - if (-1 != dev.fd_raw) - (void) close (dev.fd_raw); - return 1; - } + if (0 != seteuid (0)) + { + fprintf (stderr, "Failed to seteuid back to root: %s\n", strerror (errno)); + return 254; } #endif + /* make use of SGID capabilities on POSIX */ + memset (&dev, 0, sizeof (dev)); + dev.fd_raw = socket (PF_PACKET, SOCK_RAW, htons (ETH_P_ALL)); + raw_eno = errno; /* remember for later */ + /* now that we've dropped root rights, we can do error checking */ if (2 != argc) { @@ -1928,6 +1978,29 @@ main (int argc, char *argv[]) return 1; } + /* drop privs */ + { + uid_t uid = getuid (); +#ifdef HAVE_SETRESUID + if (0 != setresuid (uid, uid, uid)) + { + fprintf (stderr, "Failed to setresuid: %s\n", strerror (errno)); + if (-1 != dev.fd_raw) + (void) close (dev.fd_raw); + return 1; + } +#else + if (0 != (setuid (uid) | seteuid (uid))) + { + fprintf (stderr, "Failed to setuid: %s\n", strerror (errno)); + if (-1 != dev.fd_raw) + (void) close (dev.fd_raw); + return 1; + } +#endif + } + + /* send MAC address of the WLAN interface to STDOUT first */ { struct GNUNET_TRANSPORT_WLAN_HelperControlMessage macmsg;