libmac_sender.c File Reference

Code sample that illustrates the use of the send functions and the parameter information functions. More...

#include <libmac/libmac.h>

Defines
#define	PRESET_PAYLOAD_SIZE   104
	Fixed, arbitrary size for payload.
Functions
int	main (int argc, char *argv[])

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Detailed Description

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Function Documentation

int main (  int  argc, char *  argv[] )

Example usage, of the send-side functions alongwith the parameter information functions and the interface information functions, follows. This piece of code obtains the list of interfaces using the mac_get_ifinfo function and initializes the parameter structs using the mac_init_params function, requests driver to return parameters using the mac_get_params function, requests driver to set parameters using the mac_set_params function, for the wireless interface passed as a command-line argument, requests driver to append parameters using the mac_append_params function and sends a frame to the broadcast MAC address using the mac_send_broadcast function. frees the parameter and interface information structures using the mac_free_params and the mac_free_ifinfo functions respectively. It returns errno and prints the error information on the screen in case of failure of any of the calls. { // Initializations. int i, err; struct mac_ifinfo *ptr = NULL; struct mac_ifinfo_list *temp; struct mac_params *params_ptr = NULL; struct mac_params_flags *flags_ptr = NULL; char payload[PRESET_PAYLOAD_SIZE]; unsigned char ucast_mac[MACSIZE]; if (argc < 2) { printf("Usage: ./sender name_of_interface.\n"); return(-1); } // Setting the payload as an arbitrary string of characters. memset(payload, 'a', PRESET_PAYLOAD_SIZE); // If sending to a unicast MAC address, then store the address in this array. ucast_mac[0] = 0x00; ucast_mac[1] = 0x02; ucast_mac[2] = 0x2D; ucast_mac[3] = 0x6D; ucast_mac[4] = 0x16; ucast_mac[5] = 0xAB; // START: ALLOCATE MEMORY FOR THE LIBRARY STRUCTS. // Get interface information. if ( (err = mac_get_ifinfo(&ptr)) ) { #ifdef DEBUG_ERR printf("Error, error code: %d, %s\n\n", err, strerror(err)); #endif return err; } // Initialize params. struct. and params_flags struct. if ( (err = mac_init_params(&params_ptr, &flags_ptr)) ) { #ifdef DEBUG_ERR printf("Error, error code: %d, %s\n\n", err, strerror(err)); #endif return err; } // END: ALLOCATE MEMORY FOR THE LIBRARY STRUCTS. #ifdef DEBUG_BASIC // Go through the list of interfaces. temp = ptr->mac_list; while (temp != NULL) { // Call the resp. library functions for the interface eth2. if ( !(strcmp(temp->if_name, argv[1])) ) { #ifdef DEBUG_ADV fprintf(stdout, "%s: %s (ip_addr), %s (hw_addr)\n", temp->if_name, temp->ip_addr, pr_ether(temp->hw_addr)); if(temp->mac_flag) fprintf(stdout, "%s: Wireless interface\n", temp->if_name); else fprintf(stdout, "%s: Not wireless interface\n", temp->if_name); if( (temp->link_struct == NULL) && (temp->pcap_descr == NULL) ) fprintf(stdout, "%s: libnet and libpcap pointers are NULL\n", temp->if_name); #endif printf("---------- FOR INTERFACE %s -----------\n", temp->if_name); /* Get parameter information from this interface and store it in the mac_params struct. */ if ( (err = mac_get_params(params_ptr, temp, 4, mac_rssi, mac_txpower, mac_noise, mac_currentXmitRate)) ) { #ifdef DEBUG_ERR printf("Error, error code: %d, %s\n\n", err, strerror(err)); #endif return err; } // Print out parameter information retrieved from interface. printf("----------- VALUES AFTER CALL TO GET -----------------\n"); for (i = START_PARAMS_KEY; i < 4; i++) printf("Key: %d, Value: %d\n", params_ptr->key[i], params_ptr->value[i]); // Try to set parameters to the values specified. if ( (err = mac_set_params(params_ptr, temp, 4, mac_noise, 10, mac_rssi, 88, mac_txpower, 50, mac_currentXmitRate, 11000000)) ) { #ifdef DEBUG_ERR printf("Error, error code: %d, %s\n\n", err, strerror(err)); #endif return err; } /* Print out the values to which the parameters have been set. If the value printed here corresponds to the largest integer value, it means that the parameter is read-only. If it prints out the largest negative integer value, it means that the parameter is unsupported. */ printf("----------- VALUES AFTER CALL TO SET -----------------\n"); for (i = START_PARAMS_KEY; i < 4; i++) { printf("Key: %d, Value: %d\n", params_ptr->key[i], params_ptr->value[i]); } /* Call function to append parameter information on all outgoing frames. The parameters to be appended in this case are mac_txpower and mac_currentXmitRate. */ if ( (err = mac_append_params(temp, OUTGOING, 2, mac_txpower, mac_currentXmitRate)) ) { #ifdef DEBUG_ERR printf("Error, error code: %d, %s\n\n", err, strerror(err)); #endif return err; } for (i=0;i<2;i++) { /* Send frame, of type 0x0900, on specified interface, to a unicast MAC address. */ if ( (err = mac_send_broadcast(payload, PRESET_PAYLOAD_SIZE, temp)) ) { #ifdef DEBUG_ERR printf("Error, error code: %d, %s\n\n", err, strerror(err)); #endif return err; } } } temp = temp->next; } #endif // START: FREE MEMORY ALLOCATED FOR THE LIBRARY STRUCTS. // Free parameter data structures. mac_free_params(&params_ptr, &flags_ptr); // Free interface information collected and return. mac_free_ifinfo(&ptr); // END: FREE MEMORY ALLOCATED FOR THE LIBRARY STRUCTS. return 0; }

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