| 1 | #if (HAVE_CONFIG_H) |
| 2 | #include "../include/config.h" |
| 3 | #endif |
| 4 | |
| 5 | #include "include/libnet.h" |
| 6 | |
| 7 | #include "include/pg.h" |
| 8 | #include "include/packet.h" |
| 9 | |
| 10 | /* AJXXXX */ |
| 11 | libnet_t * libnet_init_pkt(int injection_type, char *device, char *err_buf); |
| 12 | int libnet_write_pkt(libnet_t *l, u_int8_t **packet, u_int32_t *len, |
| 13 | u_int32_t align); |
| 14 | void libnet_print_pkt(u_int8_t *pktbuf, u_int32_t pktlen); |
| 15 | |
| 16 | |
| 17 | extern unsigned char * genPayload (int data_type, unsigned int seed, |
| 18 | int data_length); |
| 19 | extern unsigned char * addPayload (unsigned char *p1, int l1, |
| 20 | unsigned char *p2, int l2) ; |
| 21 | extern unsigned char * addCrc (unsigned char *p1, int l1, unsigned int crc) ; |
| 22 | extern unsigned char * addL2Pad(unsigned char * pktbuf,int pktlen,int l2_pad_length) ; |
| 23 | |
| 24 | extern int libnet_gen_l4_packet(struct packet_desc *packet_vars, libnet_t *l); |
| 25 | extern int libnet_gen_l3_packet(struct packet_desc *packet_vars, libnet_t *l); |
| 26 | extern int libnet_gen_l2_packet(struct packet_desc *packet_vars, libnet_t *l); |
| 27 | |
| 28 | |
| 29 | |
| 30 | char * libnet_call(struct packet_desc *packet_vars, u_int32_t *total_len) { |
| 31 | |
| 32 | int c; |
| 33 | libnet_t *l; |
| 34 | char errbuf[LIBNET_ERRBUF_SIZE]; |
| 35 | /* AJXXXX */ |
| 36 | struct libnet_stats ls; |
| 37 | u_int32_t pktlen=0; |
| 38 | u_int32_t pktalign=0; |
| 39 | u_int8_t *pktbuf=NULL; |
| 40 | u_int32_t crc; |
| 41 | int status; |
| 42 | int l2_length; |
| 43 | int payload_start_ptr; |
| 44 | |
| 45 | |
| 46 | /* |
| 47 | * Initialize the library. Root priviledges are required. |
| 48 | */ |
| 49 | /* AJXXXX */ |
| 50 | l = libnet_init_pkt( |
| 51 | LIBNET_LINK, /* injection type */ |
| 52 | NULL, /* network interface */ |
| 53 | errbuf); /* error buffer */ |
| 54 | |
| 55 | if (l == NULL) |
| 56 | { |
| 57 | fprintf(stderr, "libnet_init() failed: %s", errbuf); |
| 58 | exit(EXIT_FAILURE); |
| 59 | } |
| 60 | |
| 61 | |
| 62 | // The guts of packet gen |
| 63 | |
| 64 | if(packet_vars->l2_pkt_type==L2_RUNT) { |
| 65 | l2_length = packet_vars->payload.data_length; |
| 66 | if(l2_length>4) { |
| 67 | l2_length= l2_length - 4; |
| 68 | // generate payload |
| 69 | pktbuf = genPayload(packet_vars->payload.data_type, |
| 70 | packet_vars->payload.data_seed, |
| 71 | l2_length); |
| 72 | pktlen = l2_length; |
| 73 | crc = libnet_compute_crc(pktbuf,pktlen); |
| 74 | pktbuf = addCrc(pktbuf,pktlen,crc); |
| 75 | pktlen+=4; |
| 76 | *total_len = pktlen; |
| 77 | } else { /*NOCRC*/ |
| 78 | // generate payload |
| 79 | pktbuf = genPayload(packet_vars->payload.data_type, |
| 80 | packet_vars->payload.data_seed, |
| 81 | l2_length); |
| 82 | pktlen = l2_length; |
| 83 | *total_len = pktlen; |
| 84 | |
| 85 | } |
| 86 | } else { |
| 87 | status = libnet_gen_l4_packet(packet_vars, l); |
| 88 | if(status == -1) { |
| 89 | printf("ERROR libnet_gen_l4_packet failed \n"); |
| 90 | return(NULL); |
| 91 | } |
| 92 | |
| 93 | |
| 94 | status = libnet_gen_l3_packet(packet_vars, l); |
| 95 | if(status == -1) { |
| 96 | printf("ERROR libnet_gen_l3_packet failed \n"); |
| 97 | return(NULL); |
| 98 | } |
| 99 | status = libnet_gen_l2_packet(packet_vars, l); |
| 100 | if(status == -1) { |
| 101 | printf("ERROR libnet_gen_l2_packet failed \n"); |
| 102 | return(NULL); |
| 103 | } |
| 104 | |
| 105 | /* sbehera - need this for IP header alignment */ |
| 106 | pktalign = 2; |
| 107 | c = libnet_write_pkt(l, &pktbuf, &pktlen, pktalign); |
| 108 | if (c == -1) |
| 109 | { |
| 110 | fprintf(stderr, "Write error: %s\n", libnet_geterror(l)); |
| 111 | return(NULL); |
| 112 | } |
| 113 | payload_start_ptr = packet_vars->l2_hdr+packet_vars->l3_hdr+ packet_vars->l4_hdr; |
| 114 | |
| 115 | if( ( packet_vars->payload.error_code & PG_CHKSUM_ERR) ){ |
| 116 | if (packet_vars->l4_pkt_type & L4_PKT_TYPE_TCP) { |
| 117 | printf("Libnet CheckSum - %x%x\n",pktbuf[payload_start_ptr-4],pktbuf[payload_start_ptr-3]); |
| 118 | pktbuf[payload_start_ptr-4] = pktbuf[payload_start_ptr-4]^1; |
| 119 | } else if(packet_vars->l4_pkt_type & L4_PKT_TYPE_UDP) { |
| 120 | printf("Libnet CheckSum - %x%x\n",pktbuf[payload_start_ptr-2],pktbuf[payload_start_ptr-1]); |
| 121 | pktbuf[payload_start_ptr-1] = pktbuf[payload_start_ptr-1]^1; |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | |
| 126 | pktbuf = addL2Pad(pktbuf,pktlen,packet_vars->payload.l2_pad_length); |
| 127 | pktlen+=packet_vars->payload.l2_pad_length; |
| 128 | |
| 129 | crc = libnet_compute_crc(pktbuf,pktlen); |
| 130 | |
| 131 | printf(" Libnet CRC - %x \n",crc); |
| 132 | if(packet_vars->payload.error_code & PG_CRC_ERR) { |
| 133 | crc = crc^0x01010101; |
| 134 | printf("Libnet CRCError - %x \n",crc); |
| 135 | } |
| 136 | |
| 137 | pktbuf = addCrc(pktbuf,pktlen,crc); |
| 138 | pktlen+=4; |
| 139 | *total_len = pktlen; |
| 140 | } |
| 141 | |
| 142 | |
| 143 | #if 1 /* AJXXXX */ |
| 144 | // c = libnet_write_pkt(l, &pktbuf, &pktlen, pktalign); |
| 145 | // crc = libnet_compute_crc(pktbuf,pktlen); |
| 146 | // pktbuf = addCrc(pktbuf,pktlen,crc); |
| 147 | // pktlen+=4; |
| 148 | #endif |
| 149 | |
| 150 | if (c == -1) { |
| 151 | fprintf(stderr, "Write error: %s\n", libnet_geterror(l)); |
| 152 | return(NULL); |
| 153 | } else { |
| 154 | fprintf(stderr, "Wrote %d byte packet; check the wire.\n", pktlen); |
| 155 | #if 1 /* AJXXXX */ |
| 156 | // libnet_print_pkt(pktbuf, pktlen); |
| 157 | return(pktbuf); |
| 158 | #endif |
| 159 | } |
| 160 | |
| 161 | } |