First try of the wlan-helper

1 files changed, 665 insertions, 0 deletions

diff --git a/src/transport/gnunet-transport-wlan-helper.c b/src/transport/gnunet-transport-wlan-helper.c
new file mode 100644
index 000000000..6ae31a647
--- /dev/null
+++ b/src/transport/gnunet-transport-wlan-helper.c
@@ -0,0 +1,665 @@
+/*
+     This file is part of GNUnet.
+     (C) 2010 Christian Grothoff (and other contributing authors)
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file src/transport/gnunet-wlan.c
+ * @brief wlan layer two server; must run as root (SUID will do)
+ *        This code will work under GNU/Linux only.  
+ * @author David Brodski
+ *
+ * This program serves as the mediator between the wlan interface and
+ * gnunet 
+ */
+ 
+#include "gnunet_wlan.h"
+#include <pcap/pcap.h>
+
+//#include "radiotap.h"
+
+// broadcast mac
+static const char macbc[] = "13223344";
+
+// mac of this node
+char mac[] = "13223355";
+
+/* wifi bitrate to use in 500kHz units */
+
+static const u8 u8aRatesToUse[] = {
+
+        54*2,
+        48*2,
+        36*2,
+        24*2,
+        18*2,
+        12*2,
+        9*2,
+        11*2,
+        11, // 5.5
+        2*2,
+        1*2
+};
+
+/* Penumbra IEEE80211 header */
+static const u8 u8aIeeeHeader[] = {
+        0x08, 0x01, 0x00, 0x00,
+        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+        0x13, 0x22, 0x33, 0x44, 0x55, 0x66,
+        0x13, 0x22, 0x33, 0x44, 0x55, 0x66,
+        0x10, 0x86,
+};
+
+/* this is the template radiotap header we send packets out with */
+
+static const u8 u8aRadiotapHeader[] = {
+
+        0x00, 0x00, // <-- radiotap version
+        0x19, 0x00, // <- radiotap header length
+        0x6f, 0x08, 0x00, 0x00, // <-- bitmap
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // <-- timestamp
+        0x00, // <-- flags (Offset +0x10)
+        0x6c, // <-- rate (0ffset +0x11)
+        0x71, 0x09, 0xc0, 0x00, // <-- channel
+        0xde, // <-- antsignal
+        0x00, // <-- antnoise
+        0x01, // <-- antenna
+
+};
+#define OFFSET_FLAGS 0x10
+#define OFFSET_RATE 0x11
+
+// this is where we store a summary of the
+// information from the radiotap header
+
+typedef struct  {
+        int m_nChannel;
+        int m_nChannelFlags;
+        int m_nRate;
+        int m_nAntenna;
+        int m_nRadiotapFlags;
+} __attribute__((packed)) PENUMBRA_RADIOTAP_DATA;
+
+void
+Dump(u8 * pu8, int nLength)
+{
+        char sz[256], szBuf[512], szChar[17], *buf, fFirst = 1;
+        unsigned char baaLast[2][16];
+        uint n, nPos = 0, nStart = 0, nLine = 0, nSameCount = 0;
+
+        buf = szBuf;
+        szChar[0] = '\0';
+
+        for (n = 0; n < nLength; n++) {
+                baaLast[(nLine&1)^1][n&0xf] = pu8[n];
+                if ((pu8[n] < 32) || (pu8[n] >= 0x7f))
+                        szChar[n&0xf] = '.';
+                else
+                        szChar[n&0xf] = pu8[n];
+                szChar[(n&0xf)+1] = '\0';
+                nPos += sprintf(&sz[nPos], "%02X ",
+                        baaLast[(nLine&1)^1][n&0xf]);
+                if ((n&15) != 15)
+                        continue;
+                if ((memcmp(baaLast[0], baaLast[1], 16) == 0) && (!fFirst)) {
+                        nSameCount++;
+                } else {
+                        if (nSameCount)
+                                buf += sprintf(buf, "(repeated %d times)\n",
+                                        nSameCount);
+                        buf += sprintf(buf, "%04x: %s %s\n",
+                                nStart, sz, szChar);
+                        nSameCount = 0;
+                        printf("%s", szBuf);
+                        buf = szBuf;
+                }
+                nPos = 0; nStart = n+1; nLine++;
+                fFirst = 0; sz[0] = '\0'; szChar[0] = '\0';
+        }
+        if (nSameCount)
+                buf += sprintf(buf, "(repeated %d times)\n", nSameCount);
+
+        buf += sprintf(buf, "%04x: %s", nStart, sz);
+        if (n & 0xf) {
+                *buf++ = ' ';
+                while (n & 0xf) {
+                        buf += sprintf(buf, "   ");
+                        n++;
+                }
+        }
+        buf += sprintf(buf, "%s\n", szChar);
+        printf("%s", szBuf);
+}
+
+
+void
+usage(void)
+{
+        printf(
+            "Usage: wlan-hwd [options] <interface>\n\nOptions\n"
+            "-f/--fcs           Mark as having FCS (CRC) already\n"
+            "                   (pkt ends with 4 x sacrificial - chars)\n"
+            "Example:\n"
+            "  echo -n mon0 > /sys/class/ieee80211/phy0/add_iface\n"
+            "  iwconfig mon0 mode monitor\n"
+            "  ifconfig mon0 up\n"
+            "  wlan-hwd mon0        Spam down mon0 with\n"
+            "                       radiotap header first\n"
+            "\n");
+        exit(1);
+}
+
+int flagHelp = 0, flagMarkWithFCS = 0;
+int flagVerbose = 0;
+
+
+/*
+ * Radiotap parser
+ *
+ * Copyright 2007               Andy Green <andy@warmcat.com>
+ */
+
+/**
+ * ieee80211_radiotap_iterator_init - radiotap parser iterator initialization
+ * @iterator: radiotap_iterator to initialize
+ * @radiotap_header: radiotap header to parse
+ * @max_length: total length we can parse into (eg, whole packet length)
+ *
+ * Returns: 0 or a negative error code if there is a problem.
+ *
+ * This function initializes an opaque iterator struct which can then
+ * be passed to ieee80211_radiotap_iterator_next() to visit every radiotap
+ * argument which is present in the header.  It knows about extended
+ * present headers and handles them.
+ *
+ * How to use:
+ * call __ieee80211_radiotap_iterator_init() to init a semi-opaque iterator
+ * struct ieee80211_radiotap_iterator (no need to init the struct beforehand)
+ * checking for a good 0 return code.  Then loop calling
+ * __ieee80211_radiotap_iterator_next()... it returns either 0,
+ * -ENOENT if there are no more args to parse, or -EINVAL if there is a problem.
+ * The iterator's @this_arg member points to the start of the argument
+ * associated with the current argument index that is present, which can be
+ * found in the iterator's @this_arg_index member.  This arg index corresponds
+ * to the IEEE80211_RADIOTAP_... defines.
+ *
+ * Radiotap header length:
+ * You can find the CPU-endian total radiotap header length in
+ * iterator->max_length after executing ieee80211_radiotap_iterator_init()
+ * successfully.
+ *
+ * Example code:
+ * See Documentation/networking/radiotap-headers.txt
+ */
+
+int ieee80211_radiotap_iterator_init(
+    struct ieee80211_radiotap_iterator *iterator,
+    struct ieee80211_radiotap_header *radiotap_header,
+    int max_length)
+{
+        /* Linux only supports version 0 radiotap format */
+        if (radiotap_header->it_version)
+                return -EINVAL;
+
+        /* sanity check for allowed length and radiotap length field */
+        if (max_length < le16_to_cpu(radiotap_header->it_len))
+                return -EINVAL;
+
+        iterator->rtheader = radiotap_header;
+        iterator->max_length = le16_to_cpu(radiotap_header->it_len);
+        iterator->arg_index = 0;
+        iterator->bitmap_shifter = le32_to_cpu(radiotap_header->it_present);
+        iterator->arg = (u8 *)radiotap_header + sizeof(*radiotap_header);
+        iterator->this_arg = 0;
+
+        /* find payload start allowing for extended bitmap(s) */
+
+        if (unlikely(iterator->bitmap_shifter & (1<<IEEE80211_RADIOTAP_EXT))) {
+                while (le32_to_cpu(*((u32 *)iterator->arg)) &
+                                   (1<<IEEE80211_RADIOTAP_EXT)) {
+                        iterator->arg += sizeof(u32);
+
+                        /*
+                         * check for insanity where the present bitmaps
+                         * keep claiming to extend up to or even beyond the
+                         * stated radiotap header length
+                         */
+
+                        if (((ulong)iterator->arg -
+                             (ulong)iterator->rtheader) > iterator->max_length)
+                                return -EINVAL;
+                }
+
+                iterator->arg += sizeof(u32);
+
+                /*
+                 * no need to check again for blowing past stated radiotap
+                 * header length, because ieee80211_radiotap_iterator_next
+                 * checks it before it is dereferenced
+                 */
+        }
+
+        /* we are all initialized happily */
+
+        return 0;
+}
+
+
+/**
+ * ieee80211_radiotap_iterator_next - return next radiotap parser iterator arg
+ * @iterator: radiotap_iterator to move to next arg (if any)
+ *
+ * Returns: 0 if there is an argument to handle,
+ * -ENOENT if there are no more args or -EINVAL
+ * if there is something else wrong.
+ *
+ * This function provides the next radiotap arg index (IEEE80211_RADIOTAP_*)
+ * in @this_arg_index and sets @this_arg to point to the
+ * payload for the field.  It takes care of alignment handling and extended
+ * present fields.  @this_arg can be changed by the caller (eg,
+ * incremented to move inside a compound argument like
+ * IEEE80211_RADIOTAP_CHANNEL).  The args pointed to are in
+ * little-endian format whatever the endianess of your CPU.
+ */
+
+int ieee80211_radiotap_iterator_next(
+    struct ieee80211_radiotap_iterator *iterator)
+{
+
+        /*
+         * small length lookup table for all radiotap types we heard of
+         * starting from b0 in the bitmap, so we can walk the payload
+         * area of the radiotap header
+         *
+         * There is a requirement to pad args, so that args
+         * of a given length must begin at a boundary of that length
+         * -- but note that compound args are allowed (eg, 2 x u16
+         * for IEEE80211_RADIOTAP_CHANNEL) so total arg length is not
+         * a reliable indicator of alignment requirement.
+         *
+         * upper nybble: content alignment for arg
+         * lower nybble: content length for arg
+         */
+
+        static const u8 rt_sizes[] = {
+                [IEEE80211_RADIOTAP_TSFT] = 0x88,
+                [IEEE80211_RADIOTAP_FLAGS] = 0x11,
+                [IEEE80211_RADIOTAP_RATE] = 0x11,
+                [IEEE80211_RADIOTAP_CHANNEL] = 0x24,
+                [IEEE80211_RADIOTAP_FHSS] = 0x22,
+                [IEEE80211_RADIOTAP_DBM_ANTSIGNAL] = 0x11,
+                [IEEE80211_RADIOTAP_DBM_ANTNOISE] = 0x11,
+                [IEEE80211_RADIOTAP_LOCK_QUALITY] = 0x22,
+                [IEEE80211_RADIOTAP_TX_ATTENUATION] = 0x22,
+                [IEEE80211_RADIOTAP_DB_TX_ATTENUATION] = 0x22,
+                [IEEE80211_RADIOTAP_DBM_TX_POWER] = 0x11,
+                [IEEE80211_RADIOTAP_ANTENNA] = 0x11,
+                [IEEE80211_RADIOTAP_DB_ANTSIGNAL] = 0x11,
+                [IEEE80211_RADIOTAP_DB_ANTNOISE] = 0x11
+                /*
+                 * add more here as they are defined in
+                 * include/net/ieee80211_radiotap.h
+                 */
+        };
+
+        /*
+         * for every radiotap entry we can at
+         * least skip (by knowing the length)...
+         */
+
+        while (iterator->arg_index < sizeof(rt_sizes)) {
+                int hit = 0;
+                int pad;
+
+                if (!(iterator->bitmap_shifter & 1))
+                        goto next_entry; /* arg not present */
+
+                /*
+                 * arg is present, account for alignment padding
+                 *  8-bit args can be at any alignment
+                 * 16-bit args must start on 16-bit boundary
+                 * 32-bit args must start on 32-bit boundary
+                 * 64-bit args must start on 64-bit boundary
+                 *
+                 * note that total arg size can differ from alignment of
+                 * elements inside arg, so we use upper nybble of length
+                 * table to base alignment on
+                 *
+                 * also note: these alignments are ** relative to the
+                 * start of the radiotap header **.  There is no guarantee
+                 * that the radiotap header itself is aligned on any
+                 * kind of boundary.
+                 */
+
+                pad = (((ulong)iterator->arg) -
+                        ((ulong)iterator->rtheader)) &
+                        ((rt_sizes[iterator->arg_index] >> 4) - 1);
+
+                if (pad)
+                        iterator->arg_index +=
+                                (rt_sizes[iterator->arg_index] >> 4) - pad;
+
+                /*
+                 * this is what we will return to user, but we need to
+                 * move on first so next call has something fresh to test
+                 */
+                iterator->this_arg_index = iterator->arg_index;
+                iterator->this_arg = iterator->arg;
+                hit = 1;
+
+                /* internally move on the size of this arg */
+                iterator->arg += rt_sizes[iterator->arg_index] & 0x0f;
+
+                /*
+                 * check for insanity where we are given a bitmap that
+                 * claims to have more arg content than the length of the
+                 * radiotap section.  We will normally end up equalling this
+                 * max_length on the last arg, never exceeding it.
+                 */
+
+                if (((ulong)iterator->arg - (ulong)iterator->rtheader) >
+                    iterator->max_length)
+                        return -EINVAL;
+
+        next_entry:
+                iterator->arg_index++;
+                if (unlikely((iterator->arg_index & 31) == 0)) {
+                        /* completed current u32 bitmap */
+                        if (iterator->bitmap_shifter & 1) {
+                                /* b31 was set, there is more */
+                                /* move to next u32 bitmap */
+                                iterator->bitmap_shifter =
+                                    le32_to_cpu(*iterator->next_bitmap);
+                                iterator->next_bitmap++;
+                        } else {
+                                /* no more bitmaps: end */
+                                iterator->arg_index = sizeof(rt_sizes);
+                        }
+                } else { /* just try the next bit */
+                        iterator->bitmap_shifter >>= 1;
+                }
+
+                /* if we found a valid arg earlier, return it now */
+                if (hit)
+                        return 0;
+        }
+
+        /* we don't know how to handle any more args, we're done */
+        return -ENOENT;
+}
+
+
+
+int
+main(int argc, char *argv[])
+{
+        u8 u8aSendBuffer[500];
+        char szErrbuf[PCAP_ERRBUF_SIZE];
+        int nCaptureHeaderLength = 0, n80211HeaderLength = 0, nLinkEncap = 0;
+        int nOrdinal = 0, r, nDelay = 100000;
+        int nRateIndex = 0, retval, bytes;
+        pcap_t *ppcap = NULL;
+        struct bpf_program bpfprogram;
+        char * szProgram = "", fBrokenSocket = 0;
+        u16 u16HeaderLen;
+        char szHostname[PATH_MAX];
+
+        if (gethostname(szHostname, sizeof (szHostname) - 1)) {
+                perror("unable to get hostname");
+        }
+        szHostname[sizeof (szHostname) - 1] = '\0';
+
+
+        printf("Packetspammer (c)2007 Andy Green <andy@warmcat.com>  GPL2\n");
+
+        while (1) {
+                int nOptionIndex;
+                static const struct option optiona[] = {
+                        { "delay", required_argument, NULL, 'd' },
+                        { "fcs", no_argument, &flagMarkWithFCS, 1 },
+                        { "help", no_argument, &flagHelp, 1 },
+                        { "verbose", no_argument, &flagVerbose, 1},
+                        { 0, 0, 0, 0 }
+                };
+                int c = getopt_long(argc, argv, "d:hf",
+                        optiona, &nOptionIndex);
+
+                if (c == -1)
+                        break;
+                switch (c) {
+                case 0: // long option
+                        break;
+
+                case 'h': // help
+                        usage();
+
+                case 'd': // delay
+                        nDelay = atoi(optarg);
+                        break;
+
+                case 'f': // mark as FCS attached
+                        flagMarkWithFCS = 1;
+                        break;
+
+                case 'v': //Verbose / readable output to cout
+                        flagVerbose = 1;
+                        break;
+
+                default:
+                        printf("unknown switch %c\n", c);
+                        usage();
+                        break;
+                }
+        }
+
+        if (optind >= argc)
+                usage();
+
+
+                // open the interface in pcap
+
+        szErrbuf[0] = '\0';
+        ppcap = pcap_open_live(argv[optind], 800, 1, 20, szErrbuf);
+        if (ppcap == NULL) {
+                printf("Unable to open interface %s in pcap: %s\n",
+                    argv[optind], szErrbuf);
+                return (1);
+        }
+
+        //get mac from interface
+
+        /*int sock, j, k;
+        char mac[32];
+
+        sock=socket(PF_INET, SOCK_STREAM, 0);
+        if (-1==sock) {
+                perror("can not open socket\n");
+                return 1;
+        }
+
+        if (-1==ioctl(sock, SIOCGIFHWADDR, &ifr)) {
+                perror("ioctl(SIOCGIFHWADDR) ");
+                return 1;
+        }
+        for (j=0, k=0; j<6; j++) {
+                k+=snprintf(mac+k, sizeof(mac)-k-1, j ? ":%02X" : "%02X",
+                        (int)(unsigned int)(unsigned char)ifr.ifr_hwaddr.sa_data[j]);
+        }
+        mac[sizeof(mac)-1]='\0';
+        */
+
+        //get header type
+        nLinkEncap = pcap_datalink(ppcap);
+        nCaptureHeaderLength = 0;
+
+        switch (nLinkEncap) {
+
+                case DLT_PRISM_HEADER:
+                        printf("DLT_PRISM_HEADER Encap\n");
+                        nCaptureHeaderLength = 0x40;
+                        n80211HeaderLength = 0x20; // ieee80211 comes after this
+                        szProgram = "radio[0x4a:4]==0x13223344";
+                        break;
+
+                case DLT_IEEE802_11_RADIO:
+                        printf("DLT_IEEE802_11_RADIO Encap\n");
+                        nCaptureHeaderLength = 0x40;
+                        n80211HeaderLength = 0x18; // ieee80211 comes after this
+                        szProgram = "ether[0x0a:4]==0x13223344";
+                        break;
+
+                default:
+                        printf("!!! unknown encapsulation on %s !\n", argv[1]);
+                        return (1);
+
+        }
+
+        if (pcap_compile(ppcap, &bpfprogram, szProgram, 1, 0) == -1) {
+                puts(szProgram);
+                puts(pcap_geterr(ppcap));
+                return (1);
+        } else {
+                if (pcap_setfilter(ppcap, &bpfprogram) == -1) {
+                        puts(szProgram);
+                        puts(pcap_geterr(ppcap));
+                } else {
+                        printf("RX Filter applied\n");
+                }
+                pcap_freecode(&bpfprogram);
+        }
+
+        pcap_setnonblock(ppcap, 1, szErrbuf);
+
+        printf("   (delay between packets %dus)\n", nDelay);
+
+        memset(u8aSendBuffer, 0, sizeof (u8aSendBuffer));
+
+        while (!fBrokenSocket) {
+                u8 * pu8 = u8aSendBuffer;
+                struct pcap_pkthdr * ppcapPacketHeader = NULL;
+                struct ieee80211_radiotap_iterator rti;
+                PENUMBRA_RADIOTAP_DATA prd;
+                u8 * pu8Payload = u8aSendBuffer;
+                int n, nRate;
+
+                // receive
+
+                retval = pcap_next_ex(ppcap, &ppcapPacketHeader,
+                    (const u_char**)&pu8Payload);
+
+                if (retval < 0) {
+                        fBrokenSocket = 1;
+                        continue;
+                }
+
+                if (retval != 1)
+                        goto do_tx;
+
+                u16HeaderLen = (pu8Payload[2] + (pu8Payload[3] << 8));
+
+                printf("rtap: ");
+                Dump(pu8Payload, u16HeaderLen);
+
+                if (ppcapPacketHeader->len <
+                    (u16HeaderLen + n80211HeaderLength))
+                        continue;
+
+                bytes = ppcapPacketHeader->len -
+                        (u16HeaderLen + n80211HeaderLength);
+                if (bytes < 0)
+                        continue;
+
+                if (ieee80211_radiotap_iterator_init(&rti,
+                    (struct ieee80211_radiotap_header *)pu8Payload,
+                    bytes) < 0)
+                        continue;
+
+                while ((n = ieee80211_radiotap_iterator_next(&rti)) == 0) {
+
+                        switch (rti.this_arg_index) {
+                        case IEEE80211_RADIOTAP_RATE:
+                                prd.m_nRate = (*rti.this_arg);
+                                break;
+
+                        case IEEE80211_RADIOTAP_CHANNEL:
+                                prd.m_nChannel =
+                                    le16_to_cpu(*((u16 *)rti.this_arg));
+                                prd.m_nChannelFlags =
+                                    le16_to_cpu(*((u16 *)(rti.this_arg + 2)));
+                                break;
+
+                        case IEEE80211_RADIOTAP_ANTENNA:
+                                prd.m_nAntenna = (*rti.this_arg) + 1;
+                                break;
+
+                        case IEEE80211_RADIOTAP_FLAGS:
+                                prd.m_nRadiotapFlags = *rti.this_arg;
+                                break;
+
+                        }
+                }
+
+                pu8Payload += u16HeaderLen + n80211HeaderLength;
+
+                if (prd.m_nRadiotapFlags & IEEE80211_RADIOTAP_F_FCS)
+                        bytes -= 4;
+
+                printf("RX: Rate: %2d.%dMbps, Freq: %d.%dGHz, "
+                    "Ant: %d, Flags: 0x%X\n",
+                    prd.m_nRate / 2, 5 * (prd.m_nRate & 1),
+                    prd.m_nChannel / 1000,
+                    prd.m_nChannel - ((prd.m_nChannel / 1000) * 1000),
+                    prd.m_nAntenna,
+                    prd.m_nRadiotapFlags);
+
+                Dump(pu8Payload, bytes);
+
+        do_tx:
+
+                // transmit
+
+                memcpy(u8aSendBuffer, u8aRadiotapHeader,
+                        sizeof (u8aRadiotapHeader));
+                if (flagMarkWithFCS)
+                        pu8[OFFSET_FLAGS] |= IEEE80211_RADIOTAP_F_FCS;
+                nRate = pu8[OFFSET_RATE] = u8aRatesToUse[nRateIndex++];
+                if (nRateIndex >= sizeof (u8aRatesToUse))
+                        nRateIndex = 0;
+                pu8 += sizeof (u8aRadiotapHeader);
+
+                memcpy(pu8, u8aIeeeHeader, sizeof (u8aIeeeHeader));
+                pu8 += sizeof (u8aIeeeHeader);
+
+                pu8 += sprintf((char *)pu8,
+                    "Packetspammer %02d"
+                    "broadcast packet"
+                    "#%05d -- :-D --%s ----",
+                    nRate/2, nOrdinal++, szHostname);
+                r = pcap_inject(ppcap, u8aSendBuffer, pu8 - u8aSendBuffer);
+                if (r != (pu8-u8aSendBuffer)) {
+                        perror("Trouble injecting packet");
+                        return (1);
+                }
+                if (nDelay)
+                        usleep(nDelay);
+        }
+
+
+
+        return (0);
+}