ipmid.C - openbmc/phosphor-host-ipmid - Gitiles

 #include <stdio.h>
 #include <dlfcn.h>
 #include <iostream>
 #include <unistd.h>
 #include <assert.h>
 #include <dirent.h>
 #include <systemd/sd-bus.h>
 #include <string.h>
 #include <stdlib.h>
 #include <map>
 #include "ipmid.H"
 #include <sys/time.h>
 #include <errno.h>


 sd_bus *bus = NULL;

 // Channel that is used for OpenBMC Barreleye
 const char * DBUS_NAME = "org.openbmc.HostIpmi";
 const char * OBJ_NAME = "/org/openbmc/HostIpmi/1";

 const char * FILTER = "type='signal',sender='org.openbmc.HostIpmi',member='ReceivedMessage'";


 typedef std::pair<ipmi_netfn_t, ipmi_cmd_t> ipmi_fn_cmd_t;
 typedef std::pair<ipmid_callback_t, ipmi_context_t> ipmi_fn_context_t;

 // Global data structure that contains the IPMI command handler's registrations.
 std::map<ipmi_fn_cmd_t, ipmi_fn_context_t> g_ipmid_router_map;


 #ifndef HEXDUMP_COLS
 #define HEXDUMP_COLS 16
 #endif

 void hexdump(void *mem, size_t len)
 {
         unsigned int i, j;

         for(i = 0; i < len + ((len % HEXDUMP_COLS) ? (HEXDUMP_COLS - len % HEXDUMP_COLS) : 0); i++)
         {
                 /* print offset */
                 if(i % HEXDUMP_COLS == 0)
                 {
                         printf("0x%06x: ", i);
                 }

                 /* print hex data */
                 if(i < len)
                 {
                         printf("%02x ", 0xFF & ((char*)mem)[i]);
                 }
                 else /* end of block, just aligning for ASCII dump */
                 {
                         printf("   ");
                 }

                 /* print ASCII dump */
                 if(i % HEXDUMP_COLS == (HEXDUMP_COLS - 1))
                 {
                         for(j = i - (HEXDUMP_COLS - 1); j <= i; j++)
                         {
                                 if(j >= len) /* end of block, not really printing */
                                 {
                                         putchar(' ');
                                 }
                                 else if(isprint(((char*)mem)[j])) /* printable char */
                                 {
                                         putchar(0xFF & ((char*)mem)[j]);
                                 }
                                 else /* other char */
                                 {
                                         putchar('.');
                                 }
                         }
                         putchar('\n');
                 }
         }
 }


 // Method that gets called by shared libraries to get their command handlers registered
 void ipmi_register_callback(ipmi_netfn_t netfn, ipmi_cmd_t cmd,
                        ipmi_context_t context, ipmid_callback_t handler)
 {
     // Pack NetFn and Command in one.
     auto netfn_and_cmd = std::make_pair(netfn, cmd);

     // Pack Function handler and Data in another.
     auto handler_and_context = std::make_pair(handler, context);

     // Check if the registration has already been made..
     auto iter = g_ipmid_router_map.find(netfn_and_cmd);
     if(iter != g_ipmid_router_map.end())
     {
         fprintf(stderr,"ERROR : Duplicate registration for NetFn [0x%X], Cmd:[0x%X]\n",netfn, cmd);
     }
     else
     {
         // This is a fresh registration.. Add it to the map.
         g_ipmid_router_map.emplace(netfn_and_cmd, handler_and_context);
     }

     return;
 }

 // Looks at the map and calls corresponding handler functions.
 ipmi_ret_t ipmi_netfn_router(ipmi_netfn_t netfn, ipmi_cmd_t cmd, ipmi_request_t request,
                       ipmi_response_t response, ipmi_data_len_t data_len)
 {
     // return from the Command handlers.
     ipmi_ret_t rc = IPMI_CC_INVALID;

     // Walk the map that has the registered handlers and invoke the approprite
     // handlers for matching commands.
     auto iter = g_ipmid_router_map.find(std::make_pair(netfn, cmd));
     if(iter == g_ipmid_router_map.end())
     {
         printf("No registered handlers for NetFn:[0x%X], Cmd:[0x%X]"
                " trying Wilcard implementation \n",netfn, cmd);

         // Now that we did not find any specific [NetFn,Cmd], tuple, check for
         // NetFn, WildCard command present.
         iter = g_ipmid_router_map.find(std::make_pair(netfn, IPMI_CMD_WILDCARD));
         if(iter == g_ipmid_router_map.end())
         {
             printf("No Registered handlers for NetFn:[0x%X],Cmd:[0x%X]\n",netfn, IPMI_CMD_WILDCARD);

             // Respond with a 0xC1
             memcpy(response, &rc, IPMI_CC_LEN);
             *data_len = IPMI_CC_LEN;
             return rc;
         }
     }

 #ifdef __IPMI_DEBUG__
     // We have either a perfect match -OR- a wild card atleast,
     printf("Calling Net function:[0x%X], Command:[0x%X]\n", netfn, cmd);
 #endif

     // Extract the map data onto appropriate containers
     auto handler_and_context = iter->second;

     // Creating a pointer type casted to char* to make sure we advance 1 byte
     // when we advance pointer to next's address. advancing void * would not
     // make sense.
     char *respo = &((char *)response)[IPMI_CC_LEN];

     // Response message from the plugin goes into a byte post the base response
     rc = (handler_and_context.first) (netfn, cmd, request, respo,
                                       data_len, handler_and_context.second);

     // Now copy the return code that we got from handler and pack it in first
     // byte.
     memcpy(response, &rc, IPMI_CC_LEN);

     // Data length is now actual data + completion code.
     *data_len = *data_len + IPMI_CC_LEN;

     return rc;
 }


 static int send_ipmi_message(unsigned char seq, unsigned char netfn, unsigned char cmd, unsigned char *buf, unsigned char len) {

     sd_bus_error error = SD_BUS_ERROR_NULL;
     sd_bus_message *reply = NULL, *m=NULL;


     const char *path;
     int r, pty;


     r = sd_bus_message_new_method_call(bus,&m,DBUS_NAME,OBJ_NAME,DBUS_NAME,"sendMessage");
     if (r < 0) {
         fprintf(stderr, "Failed to add the method object: %s\n", strerror(-r));
         return -1;
     }


     // Responses in IPMI require a bit set.  So there ya go...
     netfn |= 0x04;


     // Add the bytes needed for the methods to be called
     r = sd_bus_message_append(m, "yyy", seq, netfn, cmd);
     if (r < 0) {
         fprintf(stderr, "Failed add the netfn and others : %s\n", strerror(-r));
         return -1;
     }

     r = sd_bus_message_append_array(m, 'y', buf, len);
     if (r < 0) {
         fprintf(stderr, "Failed to add the string of response bytes: %s\n", strerror(-r));
         return -1;
     }


     // Call the IPMI responder on the bus so the message can be sent to the CEC
     r = sd_bus_call(bus, m, 0, &error, &reply);
     if (r < 0) {
         fprintf(stderr, "Failed to call the method: %s", strerror(-r));
         return -1;
     }

     r = sd_bus_message_read(reply, "x", &pty);
 #ifdef __IPMI_DEBUG__
     printf("RC from the ipmi dbus method :%d \n", pty);
 #endif
     if (r < 0) {
        fprintf(stderr, "Failed to get a rc from the method: %s\n", strerror(-r));

     }


     sd_bus_error_free(&error);
     sd_bus_message_unref(m);


 #ifdef __IPMI_DEBUG__
     printf("%d : %s\n", __LINE__, __PRETTY_FUNCTION__ );
 #endif
     return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;

 }

 static int handle_ipmi_command(sd_bus_message *m, void *user_data, sd_bus_error
                          *ret_error) {
     int r = 0;
     const char *msg = NULL;
     char sequence, netfn, cmd;
     const void *request;
     size_t sz;
     size_t resplen =MAX_IPMI_BUFFER;
     unsigned char response[MAX_IPMI_BUFFER];

     printf(" *** Received Signal: ");

     memset(response, 0, MAX_IPMI_BUFFER);

     r = sd_bus_message_read(m, "yyy",  &sequence, &netfn, &cmd);
     if (r < 0) {
         fprintf(stderr, "Failed to parse signal message: %s\n", strerror(-r));
         return -1;
     }

     r = sd_bus_message_read_array(m, 'y',  &request, &sz );
     if (r < 0) {
         fprintf(stderr, "Failed to parse signal message: %s\n", strerror(-r));
         return -1;
     }


     printf("Seq 0x%02x, NetFn 0x%02x, CMD: 0x%02x \n", sequence, netfn, cmd);
     hexdump((void*)request, sz);

     // Allow the length field to be used for both input and output of the
     // ipmi call
     resplen = sz;

     // Now that we have parsed the entire byte array from the caller
     // we can call the ipmi router to do the work...
     r = ipmi_netfn_router(netfn, cmd, (void *)request, (void *)response, &resplen);
     if(r != 0)
     {
         fprintf(stderr,"ERROR:[0x%X] handling NetFn:[0x%X], Cmd:[0x%X]\n",r, netfn, cmd);
     }

     printf("Response...\n");
     hexdump((void*)response, resplen);

     // Send the response buffer from the ipmi command
     r = send_ipmi_message(sequence, netfn, cmd, response, resplen);
     if (r < 0) {
         fprintf(stderr, "Failed to send the response message\n");
         return -1;
     }


     return 0;
 }


 //----------------------------------------------------------------------
 // handler_select
 // Select all the files ending with with .so. in the given diretcory
 // @d: dirent structure containing the file name
 //----------------------------------------------------------------------
 int handler_select(const struct dirent *entry)
 {
     // To hold ".so" from entry->d_name;
     char dname_copy[4] = {0};

     // We want to avoid checking for everything and isolate to the ones having
     // .so in them.
     if(strstr(entry->d_name, IPMI_PLUGIN_EXTN))
     {
         // It is possible that .so could be anywhere in the string but unlikely
         // But being careful here. Get the base address of the string, move
         // until end and come back 3 steps and that gets what we need.
         strcpy(dname_copy, (entry->d_name + strlen(entry->d_name)-strlen(IPMI_PLUGIN_EXTN)));
         if(strcmp(dname_copy, IPMI_PLUGIN_EXTN) == 0)
         {
             return 1;
         }
     }
     return 0;
 }

 // This will do a dlopen of every .so in ipmi_lib_path and will dlopen everything so that they will
 // register a callback handler
 void ipmi_register_callback_handlers(const char* ipmi_lib_path)
 {
     // For walking the ipmi_lib_path
     struct dirent **handler_list;
     int num_handlers = 0;

     // This is used to check and abort if someone tries to register a bad one.
     void *lib_handler = NULL;

     if(ipmi_lib_path == NULL)
     {
         fprintf(stderr,"ERROR; No handlers to be registered for ipmi.. Aborting\n");
         assert(0);
     }
     else
     {
         // 1: Open ipmi_lib_path. Its usually "/usr/lib/phosphor-host-ipmid"
         // 2: Scan the directory for the files that end with .so
         // 3: For each one of them, just do a 'dlopen' so that they register
         //    the handlers for callback routines.

         std::string handler_fqdn = ipmi_lib_path;

         // Append a "/" since we need to add the name of the .so. If there is
         // already a .so, adding one more is not any harm.
         handler_fqdn += "/";

         num_handlers = scandir(ipmi_lib_path, &handler_list, handler_select, alphasort);
         while(num_handlers--)
         {
             handler_fqdn = ipmi_lib_path;
             handler_fqdn += handler_list[num_handlers]->d_name;
             printf("Registering handler:[%s]\n",handler_fqdn.c_str());

             lib_handler = dlopen(handler_fqdn.c_str(), RTLD_NOW);
             if(lib_handler == NULL)
             {
                 fprintf(stderr,"ERROR opening:[%s]\n",handler_fqdn.c_str());
                 dlerror();
             }
             // Wipe the memory allocated for this particular entry.
             free(handler_list[num_handlers]);
         }
         // Done with all registration.
         free(handler_list);
     }

     // TODO : What to be done on the memory that is given by dlopen ?.
     return;
 }

 int main(int argc, char *argv[])
 {
     sd_bus_slot *slot = NULL;
     int r;
     char *mode = NULL;


     // Register all the handlers that provider implementation to IPMI commands.
     ipmi_register_callback_handlers(HOST_IPMI_LIB_PATH);

 #ifdef __IPMI_DEBUG__
     printf("Registered Function handlers:\n");

     // Print the registered handlers and their arguments.
     for(auto& iter : g_ipmid_router_map)
     {
         ipmi_fn_cmd_t fn_and_cmd = iter.first;
         printf("NETFN:[0x%X], cmd[0x%X]\n", fn_and_cmd.first, fn_and_cmd.second);
     }
 #endif


     /* Connect to system bus */
     r = sd_bus_open_system(&bus);
     if (r < 0) {
         fprintf(stderr, "Failed to connect to system bus: %s\n",
                 strerror(-r));
         goto finish;
     }

     r = sd_bus_add_match(bus, &slot, FILTER, handle_ipmi_command, NULL);
     if (r < 0) {
         fprintf(stderr, "Failed: sd_bus_add_match: %s : %s\n", strerror(-r), FILTER);
         goto finish;
     }


     for (;;) {
         /* Process requests */

         r = sd_bus_process(bus, NULL);
         if (r < 0) {
             fprintf(stderr, "Failed to process bus: %s\n", strerror(-r));
             goto finish;
         }
         if (r > 0) {
             continue;
         }

         r = sd_bus_wait(bus, (uint64_t) - 1);
         if (r < 0) {
             fprintf(stderr, "Failed to wait on bus: %s\n", strerror(-r));
             goto finish;
         }
     }

 finish:
     sd_bus_slot_unref(slot);
     sd_bus_unref(bus);
     return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;

 }
	#include <stdio.h>
	#include <dlfcn.h>
	#include <iostream>
	#include <unistd.h>
	#include <assert.h>
	#include <dirent.h>
	#include <systemd/sd-bus.h>
	#include <string.h>
	#include <stdlib.h>
	#include <map>
	#include "ipmid.H"
	#include <sys/time.h>
	#include <errno.h>


	sd_bus *bus = NULL;

	// Channel that is used for OpenBMC Barreleye
	const char * DBUS_NAME = "org.openbmc.HostIpmi";
	const char * OBJ_NAME = "/org/openbmc/HostIpmi/1";

	const char * FILTER = "type='signal',sender='org.openbmc.HostIpmi',member='ReceivedMessage'";


	typedef std::pair<ipmi_netfn_t, ipmi_cmd_t> ipmi_fn_cmd_t;
	typedef std::pair<ipmid_callback_t, ipmi_context_t> ipmi_fn_context_t;

	// Global data structure that contains the IPMI command handler's registrations.
	std::map<ipmi_fn_cmd_t, ipmi_fn_context_t> g_ipmid_router_map;



	#ifndef HEXDUMP_COLS
	#define HEXDUMP_COLS 16
	#endif

	void hexdump(void *mem, size_t len)
	{
	unsigned int i, j;

	for(i = 0; i < len + ((len % HEXDUMP_COLS) ? (HEXDUMP_COLS - len % HEXDUMP_COLS) : 0); i++)
	{
	/* print offset */
	if(i % HEXDUMP_COLS == 0)
	{
	printf("0x%06x: ", i);
	}

	/* print hex data */
	if(i < len)
	{
	printf("%02x ", 0xFF & ((char*)mem)[i]);
	}
	else /* end of block, just aligning for ASCII dump */
	{
	printf(" ");
	}

	/* print ASCII dump */
	if(i % HEXDUMP_COLS == (HEXDUMP_COLS - 1))
	{
	for(j = i - (HEXDUMP_COLS - 1); j <= i; j++)
	{
	if(j >= len) /* end of block, not really printing */
	{
	putchar(' ');
	}
	else if(isprint(((char)mem)[j])) / printable char */
	{
	putchar(0xFF & ((char*)mem)[j]);
	}
	else /* other char */
	{
	putchar('.');
	}
	}
	putchar('\n');
	}
	}
	}


	// Method that gets called by shared libraries to get their command handlers registered
	void ipmi_register_callback(ipmi_netfn_t netfn, ipmi_cmd_t cmd,
	ipmi_context_t context, ipmid_callback_t handler)
	{
	// Pack NetFn and Command in one.
	auto netfn_and_cmd = std::make_pair(netfn, cmd);

	// Pack Function handler and Data in another.
	auto handler_and_context = std::make_pair(handler, context);

	// Check if the registration has already been made..
	auto iter = g_ipmid_router_map.find(netfn_and_cmd);
	if(iter != g_ipmid_router_map.end())
	{
	fprintf(stderr,"ERROR : Duplicate registration for NetFn [0x%X], Cmd:[0x%X]\n",netfn, cmd);
	}
	else
	{
	// This is a fresh registration.. Add it to the map.
	g_ipmid_router_map.emplace(netfn_and_cmd, handler_and_context);
	}

	return;
	}

	// Looks at the map and calls corresponding handler functions.
	ipmi_ret_t ipmi_netfn_router(ipmi_netfn_t netfn, ipmi_cmd_t cmd, ipmi_request_t request,
	ipmi_response_t response, ipmi_data_len_t data_len)
	{
	// return from the Command handlers.
	ipmi_ret_t rc = IPMI_CC_INVALID;

	// Walk the map that has the registered handlers and invoke the approprite
	// handlers for matching commands.
	auto iter = g_ipmid_router_map.find(std::make_pair(netfn, cmd));
	if(iter == g_ipmid_router_map.end())
	{
	printf("No registered handlers for NetFn:[0x%X], Cmd:[0x%X]"
	" trying Wilcard implementation \n",netfn, cmd);

	// Now that we did not find any specific [NetFn,Cmd], tuple, check for
	// NetFn, WildCard command present.
	iter = g_ipmid_router_map.find(std::make_pair(netfn, IPMI_CMD_WILDCARD));
	if(iter == g_ipmid_router_map.end())
	{
	printf("No Registered handlers for NetFn:[0x%X],Cmd:[0x%X]\n",netfn, IPMI_CMD_WILDCARD);

	// Respond with a 0xC1
	memcpy(response, &rc, IPMI_CC_LEN);
	*data_len = IPMI_CC_LEN;
	return rc;
	}
	}

	#ifdef __IPMI_DEBUG__
	// We have either a perfect match -OR- a wild card atleast,
	printf("Calling Net function:[0x%X], Command:[0x%X]\n", netfn, cmd);
	#endif

	// Extract the map data onto appropriate containers
	auto handler_and_context = iter->second;

	// Creating a pointer type casted to char* to make sure we advance 1 byte
	// when we advance pointer to next's address. advancing void * would not
	// make sense.
	char respo = &((char )response)[IPMI_CC_LEN];

	// Response message from the plugin goes into a byte post the base response
	rc = (handler_and_context.first) (netfn, cmd, request, respo,
	data_len, handler_and_context.second);

	// Now copy the return code that we got from handler and pack it in first
	// byte.
	memcpy(response, &rc, IPMI_CC_LEN);

	// Data length is now actual data + completion code.
	data_len = data_len + IPMI_CC_LEN;

	return rc;
	}




	static int send_ipmi_message(unsigned char seq, unsigned char netfn, unsigned char cmd, unsigned char *buf, unsigned char len) {

	sd_bus_error error = SD_BUS_ERROR_NULL;
	sd_bus_message reply = NULL, m=NULL;


	const char *path;
	int r, pty;


	r = sd_bus_message_new_method_call(bus,&m,DBUS_NAME,OBJ_NAME,DBUS_NAME,"sendMessage");
	if (r < 0) {
	fprintf(stderr, "Failed to add the method object: %s\n", strerror(-r));
	return -1;
	}


	// Responses in IPMI require a bit set. So there ya go...
	netfn \|= 0x04;


	// Add the bytes needed for the methods to be called
	r = sd_bus_message_append(m, "yyy", seq, netfn, cmd);
	if (r < 0) {
	fprintf(stderr, "Failed add the netfn and others : %s\n", strerror(-r));
	return -1;
	}

	r = sd_bus_message_append_array(m, 'y', buf, len);
	if (r < 0) {
	fprintf(stderr, "Failed to add the string of response bytes: %s\n", strerror(-r));
	return -1;
	}



	// Call the IPMI responder on the bus so the message can be sent to the CEC
	r = sd_bus_call(bus, m, 0, &error, &reply);
	if (r < 0) {
	fprintf(stderr, "Failed to call the method: %s", strerror(-r));
	return -1;
	}

	r = sd_bus_message_read(reply, "x", &pty);
	#ifdef __IPMI_DEBUG__
	printf("RC from the ipmi dbus method :%d \n", pty);
	#endif
	if (r < 0) {
	fprintf(stderr, "Failed to get a rc from the method: %s\n", strerror(-r));

	}


	sd_bus_error_free(&error);
	sd_bus_message_unref(m);


	#ifdef __IPMI_DEBUG__
	printf("%d : %s\n", __LINE__, __PRETTY_FUNCTION__ );
	#endif
	return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;

	}

	static int handle_ipmi_command(sd_bus_message m, void user_data, sd_bus_error
	*ret_error) {
	int r = 0;
	const char *msg = NULL;
	char sequence, netfn, cmd;
	const void *request;
	size_t sz;
	size_t resplen =MAX_IPMI_BUFFER;
	unsigned char response[MAX_IPMI_BUFFER];

	printf(" *** Received Signal: ");

	memset(response, 0, MAX_IPMI_BUFFER);

	r = sd_bus_message_read(m, "yyy", &sequence, &netfn, &cmd);
	if (r < 0) {
	fprintf(stderr, "Failed to parse signal message: %s\n", strerror(-r));
	return -1;
	}

	r = sd_bus_message_read_array(m, 'y', &request, &sz );
	if (r < 0) {
	fprintf(stderr, "Failed to parse signal message: %s\n", strerror(-r));
	return -1;
	}


	printf("Seq 0x%02x, NetFn 0x%02x, CMD: 0x%02x \n", sequence, netfn, cmd);
	hexdump((void*)request, sz);

	// Allow the length field to be used for both input and output of the
	// ipmi call
	resplen = sz;

	// Now that we have parsed the entire byte array from the caller
	// we can call the ipmi router to do the work...
	r = ipmi_netfn_router(netfn, cmd, (void )request, (void )response, &resplen);
	if(r != 0)
	{
	fprintf(stderr,"ERROR:[0x%X] handling NetFn:[0x%X], Cmd:[0x%X]\n",r, netfn, cmd);
	}

	printf("Response...\n");
	hexdump((void*)response, resplen);

	// Send the response buffer from the ipmi command
	r = send_ipmi_message(sequence, netfn, cmd, response, resplen);
	if (r < 0) {
	fprintf(stderr, "Failed to send the response message\n");
	return -1;
	}


	return 0;
	}


	//----------------------------------------------------------------------
	// handler_select
	// Select all the files ending with with .so. in the given diretcory
	// @d: dirent structure containing the file name
	//----------------------------------------------------------------------
	int handler_select(const struct dirent *entry)
	{
	// To hold ".so" from entry->d_name;
	char dname_copy[4] = {0};

	// We want to avoid checking for everything and isolate to the ones having
	// .so in them.
	if(strstr(entry->d_name, IPMI_PLUGIN_EXTN))
	{
	// It is possible that .so could be anywhere in the string but unlikely
	// But being careful here. Get the base address of the string, move
	// until end and come back 3 steps and that gets what we need.
	strcpy(dname_copy, (entry->d_name + strlen(entry->d_name)-strlen(IPMI_PLUGIN_EXTN)));
	if(strcmp(dname_copy, IPMI_PLUGIN_EXTN) == 0)
	{
	return 1;
	}
	}
	return 0;
	}

	// This will do a dlopen of every .so in ipmi_lib_path and will dlopen everything so that they will
	// register a callback handler
	void ipmi_register_callback_handlers(const char* ipmi_lib_path)
	{
	// For walking the ipmi_lib_path
	struct dirent **handler_list;
	int num_handlers = 0;

	// This is used to check and abort if someone tries to register a bad one.
	void *lib_handler = NULL;

	if(ipmi_lib_path == NULL)
	{
	fprintf(stderr,"ERROR; No handlers to be registered for ipmi.. Aborting\n");
	assert(0);
	}
	else
	{
	// 1: Open ipmi_lib_path. Its usually "/usr/lib/phosphor-host-ipmid"
	// 2: Scan the directory for the files that end with .so
	// 3: For each one of them, just do a 'dlopen' so that they register
	// the handlers for callback routines.

	std::string handler_fqdn = ipmi_lib_path;

	// Append a "/" since we need to add the name of the .so. If there is
	// already a .so, adding one more is not any harm.
	handler_fqdn += "/";

	num_handlers = scandir(ipmi_lib_path, &handler_list, handler_select, alphasort);
	while(num_handlers--)
	{
	handler_fqdn = ipmi_lib_path;
	handler_fqdn += handler_list[num_handlers]->d_name;
	printf("Registering handler:[%s]\n",handler_fqdn.c_str());

	lib_handler = dlopen(handler_fqdn.c_str(), RTLD_NOW);
	if(lib_handler == NULL)
	{
	fprintf(stderr,"ERROR opening:[%s]\n",handler_fqdn.c_str());
	dlerror();
	}
	// Wipe the memory allocated for this particular entry.
	free(handler_list[num_handlers]);
	}
	// Done with all registration.
	free(handler_list);
	}

	// TODO : What to be done on the memory that is given by dlopen ?.
	return;
	}

	int main(int argc, char *argv[])
	{
	sd_bus_slot *slot = NULL;
	int r;
	char *mode = NULL;


	// Register all the handlers that provider implementation to IPMI commands.
	ipmi_register_callback_handlers(HOST_IPMI_LIB_PATH);

	#ifdef __IPMI_DEBUG__
	printf("Registered Function handlers:\n");

	// Print the registered handlers and their arguments.
	for(auto& iter : g_ipmid_router_map)
	{
	ipmi_fn_cmd_t fn_and_cmd = iter.first;
	printf("NETFN:[0x%X], cmd[0x%X]\n", fn_and_cmd.first, fn_and_cmd.second);
	}
	#endif


	/* Connect to system bus */
	r = sd_bus_open_system(&bus);
	if (r < 0) {
	fprintf(stderr, "Failed to connect to system bus: %s\n",
	strerror(-r));
	goto finish;
	}

	r = sd_bus_add_match(bus, &slot, FILTER, handle_ipmi_command, NULL);
	if (r < 0) {
	fprintf(stderr, "Failed: sd_bus_add_match: %s : %s\n", strerror(-r), FILTER);
	goto finish;
	}


	for (;;) {
	/* Process requests */

	r = sd_bus_process(bus, NULL);
	if (r < 0) {
	fprintf(stderr, "Failed to process bus: %s\n", strerror(-r));
	goto finish;
	}
	if (r > 0) {
	continue;
	}

	r = sd_bus_wait(bus, (uint64_t) - 1);
	if (r < 0) {
	fprintf(stderr, "Failed to wait on bus: %s\n", strerror(-r));
	goto finish;
	}
	}

	finish:
	sd_bus_slot_unref(slot);
	sd_bus_unref(bus);
	return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;

	}