+/*
+ * Copyright: (c) 2012 Czech Technical University in Prague
+ *
+ * Authors:
+ * Radek Matějka <radek.matejka@gmail.com>
+ * Michal Sojka <sojkam1@fel.cvut.cz>
+ *
+ * This program 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
+ * 2 of the License, or (at your option) any later version.
+ */
+
+
#include <stdio.h>
#include <stdlib.h>
-#include <libgen.h>
#include <string.h>
-#include <getopt.h>
-#include <errno.h>
#include <sys/socket.h>
#include <net/if.h>
-#include <libnetlink.h>
-#include <linux/netlink.h>
-#include <linux/rtnetlink.h>
#include <arpa/inet.h>
#include <linux/can.h>
-#include <linux/types.h>
+#include <limits.h>
#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
#include "canethgw.h"
-/**
- * ToDo
- * [ ] refactor error messages
- * [ ] start/stop listening
- * [ ] remove routing job
- * [ ] recv netlink reponse
- *
- */
-
-#define CEGW_CMD_ADD 1
-#define CEGW_CMD_LIST 2
-#define CEGW_CMD_FLUSH 4
-#define CEGW_CMD_LISTEN 8
-
-enum
-{
- IF_UNDEF,
- IF_CAN,
- IF_ETH_UDP
-};
-
-struct cegw_data
-{
- int content;
- int src_if, dst_if;
- int can_ifidx;
- struct in_addr eth_addr;
- unsigned short eth_port;
- struct in_addr eth_listen_addr;
- unsigned short eth_listen_port;
-};
-
-struct cegw_nlmsg
-{
- struct nlmsghdr nh;
- struct rtmsg rt;
- char buf[768]; /* enough? */
-};
-
unsigned int cegw_errno = 0;
-enum
+enum
{
CEGW_ERR_UNKNOWN,
- CEGW_ERR_IF_UNSPEC,
- CEGW_ERR_IF_SAME,
- CEGW_ERR_IF_TYPE
+ CEGW_ERR_COLON,
+ CEGW_ERR_UNEXLEN,
+ CEGW_ERR_ATON,
+ CEGW_ERR_PORT
};
char* cegw_errlist[] =
{
- [ CEGW_ERR_UNKNOWN ] = "unknown error",
- [ CEGW_ERR_IF_UNSPEC ] = "source or destination not specified",
- [ CEGW_ERR_IF_SAME ] = "source and destination have same interface type",
- [ CEGW_ERR_IF_TYPE ] = "unknown interface type"
+ [CEGW_ERR_UNKNOWN] = "",
+ [CEGW_ERR_COLON ] = "expected ':' (<ip>:<port>)",
+ [CEGW_ERR_UNEXLEN] = "unexpected ip address length, please use dot notation"
+ " (eg. 127.0.0.1)",
+ [CEGW_ERR_ATON ] = "ip address mismatch",
+ [CEGW_ERR_PORT ] = "port number"
};
-static void perr( char* s )
+static const char help_msg[] = "usage:\n"
+ " %s <can_if> <udp_listen_addr>:<port> <udp_dest_addr>:<port>\n"
+ " [list of additional udp recipients <addr:port>]\n"
+ "example:\n"
+ " %s can0 192.168.0.1:10501 192.168.0.4:980 192.168.0.7:1160\n\n"
+ " Executing this command will set the gateway so that it will\n"
+ " listen for udp messages on 192.168.0.1:10501 and send them\n"
+ " to can0. Simultaneously, it will send all messages from can0\n"
+ " to 192.168.0.4:980 and 192.168.0.7:1160 via udp. The message is\n"
+ " therefore cloned. Notice that there can be any number\n"
+ " of udp recipients.\n";
+
+static void perr(char* s)
{
- if( s )
- {
- fprintf( stderr, "error: %s; %s\n", s,
- cegw_errlist[ cegw_errno ] );
+ if (s) {
+ if (cegw_errno == 0) {
+ fprintf(stderr, "error: %s\n", s);
+
+ } else {
+ fprintf(stderr, "error: %s, %s\n", s, cegw_errlist[cegw_errno]);
+ }
return;
}
- fprintf( stderr, "error: %s\n", cegw_errlist[ cegw_errno ] );
+ fprintf(stderr, "error: %s\n", cegw_errlist[cegw_errno]);
}
/**
- * Parses @in for eth address. Valid input is
- * e.g. udp@127.0.0.1:10502 or can@vcan0.
+ * read_addrport - parses @in for eth address.
+ * Valid input is e.g. 127.0.0.1:10502. If parsing fails
+ * the cause is stored in cegw_errno.
*
+ * @param[in] in string to search in
* @param[out] addr ip address
* @param[out] port transport layer port
- * @return 0 on success
+ * @return 0 on success, -1 otherwise
*/
-int read_addr_port( char* in, struct in_addr* addr, unsigned short* port )
+int read_addrport(char* in, struct in_addr* addr, unsigned short* port)
{
char* delim = NULL;
- char addrstr[16];
+ const int addrstr_len = 16;
+ char addrstr[addrstr_len];
int addrlen;
-
- if( (delim = strchr( in, ':' )) == NULL )
- {
- fprintf( stderr, "error: ':'\n" );
+
+ if ((delim = strchr(in, ':')) == NULL) {
+ cegw_errno = CEGW_ERR_COLON;
return -1;
}
/* get address */
addrlen = delim - in;
- memcpy( addrstr, in, addrlen );
- addrstr[addrlen] = '\0';
- if( inet_aton( addrstr, addr ) == 0 )
- {
- fprintf( stderr, "error: aton\n" );
+ if (addrlen > addrstr_len) {
+ cegw_errno = CEGW_ERR_UNEXLEN;
return -1;
}
- /* get port */
- if( sscanf( delim, ":%hu", port ) != 1 ) /* todo: handle overflow */
- {
- fprintf( stderr, "error: port\n" );
+ memcpy(addrstr, in, addrlen);
+ addrstr[addrlen] = '\0';
+ if (inet_aton(addrstr, addr) == 0) {
+ cegw_errno = CEGW_ERR_ATON;
return -1;
}
- return 0;
-}
-
-/**
- * Reads @in for iftype (e.g. "can@" or "udp@").
- *
- * @param[in] in string to search in
- * @param[out] iftype iftype detected
- * @return pointer to @in after iftype on success, NULL otherwise
- */
-char* read_iftype( char* in, int* iftype )
-{
- char* ret = in+4;
-
- if( strncmp( "udp@", optarg, 4 ) == 0 )
- {
- *iftype = IF_ETH_UDP;
- return ret;
- }
- /*
- else if( strncmp( "tcp@", optarg, 4 ) == 0 )
- {
- return NULL;
- }
- */
- else if( strncmp( "can@", optarg, 4 ) == 0 )
- {
- *iftype = IF_CAN;
- return ret;
- }
-
- errno = CEGW_ERR_IF_TYPE;
- return NULL;
-}
-
-int read_if( char* in, int* iftype, struct cegw_data* d )
-{
- char* optstr = NULL;
-
- if( (optstr = read_iftype( in, iftype )) == NULL )
- {
+ /* get port */
+ /* ToDo: handle overflow */
+ if (sscanf(delim, ":%hu", port) != 1) {
+ cegw_errno = CEGW_ERR_PORT;
return -1;
}
- switch( *iftype )
- {
- case IF_CAN:
- d->can_ifidx = if_nametoindex( optstr );
- break;
- case IF_ETH_UDP:
- read_addr_port( optstr, &d->eth_addr, &d->eth_port );
- break;
- default:
- return -1;
- break;
- }
-
return 0;
}
-inline static int cegw_add( struct cegw_nlmsg* req, struct cegw_data* d )
+int main(int argc, char* argv[])
{
- int gwtype = 0;
-
- req->nh.nlmsg_type = RTM_NEWROUTE;
- if( (d->src_if == 0 || d->dst_if == 0) )
- {
- cegw_errno = CEGW_ERR_IF_UNSPEC;
- return -cegw_errno;
- }
-
- if( d->src_if == d->dst_if )
- {
- cegw_errno = CEGW_ERR_IF_SAME;
- return -cegw_errno;
- }
-
- gwtype = (d->src_if == IF_CAN) ? CGW_TYPE_CAN_ETH_UDP : CGW_TYPE_ETH_CAN_UDP;
- addattr_l( &req->nh, sizeof(*req), CGW_CAN_IF, &d->can_ifidx, sizeof(d->can_ifidx) );
-
- switch( gwtype )
- {
- case CGW_TYPE_CAN_ETH_UDP:
- addattr_l( &req->nh, sizeof(*req), CGW_ETH_IP, &d->eth_addr, sizeof(d->eth_addr) );
- addattr_l( &req->nh, sizeof(*req), CGW_ETH_PORT, &d->eth_port, sizeof(d->eth_port) );
- break;
- case CGW_TYPE_ETH_CAN_UDP:
- break;
- default:
- break;
+ int i;
+ int fd;
+ int tmpi;
+ int dstcnt;
+ unsigned short port;
+ int udp_sock, can_sock;
+ struct sockaddr_in udp_addr;
+ struct sockaddr_can can_addr;
+ struct sockaddr_in* dst = NULL;
+ struct cegw_ioctl* gwctl = NULL;
+
+ if (argc == 1)
+ {
+ printf(help_msg, argv[0], argv[0]);
+ return 0;
+ }
+
+ if (argc < 4) {
+ perr("not enought arguments");
+ printf(help_msg, argv[0], argv[0]);
+ /* ToDo: print usage */
+ return -1;
}
- addattr32( &req->nh, sizeof(*req), CGW_CMD_INFO, gwtype );
-
- return 0;
-}
-
-inline static int cegw_listen( struct cegw_nlmsg* req, struct cegw_data* d )
-{
- req->nh.nlmsg_type = RTM_NEWROUTE;
- addattr32( &req->nh, sizeof(*req), CGW_CMD_INFO, CEGW_LISTEN );
- addattr_l( &req->nh, sizeof(*req), CGW_LISTEN_IP, &d->eth_listen_addr, sizeof(d->eth_listen_addr) );
- addattr_l( &req->nh, sizeof(*req), CGW_LISTEN_PORT, &d->eth_listen_port, sizeof(d->eth_listen_port) );
- printf( "start listen: %x, %hu\n", d->eth_listen_addr, d->eth_listen_port );
-
- return 0;
-}
-
-inline static int cegw_list( struct cegw_nlmsg* req, struct cegw_data* d )
-{
- return 0;
-}
-
-inline static int cegw_flush( struct cegw_nlmsg* req, struct cegw_data* d )
-{
-// char foo[2];
- addattr32( &req->nh, sizeof(*req), CGW_CMD_INFO, CEGW_FLUSH );
- req->nh.nlmsg_type = RTM_DELROUTE;
-// addattr_l( &req->nh, sizeof(*req), 0, &foo, sizeof(foo) );
- //addattr_l( &req->nh, sizeof(*req), CGW_CAN_IF, &d->can_ifidx, sizeof(d->can_ifidx) );
-// req->rtcan.gwtype = CGW_TYPE_CAN_ETH_UDP;
-// req->rtcan.flags = 5;//CEGW_FLUSH;
- return 0;
-}
-
-int main( int argc, char* argv[] )
-{
- int s;
- int tmp = 0;
- int cmd = 0;
- char* optstr;
- char opt;
- struct sockaddr_nl nladdr;
- int err = 0;
- struct cegw_nlmsg req;
- struct cegw_data d;
- char rxbuf[256]; /* 8129+ ? */
- int rsize = 0;
- struct nlmsghdr* nlh;
- struct nlmsgerr* rte;
-
- printf( "size=%d\n", NLMSG_LENGTH(sizeof(struct rtmsg)) );
-
- memset( &d, 0, sizeof(d) );
-
- struct option long_opt[] =
- {
- { "add" , 0, NULL, 'A' },
- { "flush" , 0, NULL, 'F' },
- { "list" , 0, NULL, 'L' },
- { "listen", 1, NULL, 'l' },
- { 0, 0, 0, 0 }
- };
-
- while( 1 )
- {
- opt = getopt_long( argc, argv, "As:d:", long_opt, NULL );
- if( opt == -1 )
- break;
+ dstcnt = argc-3;
+ gwctl = (struct cegw_ioctl*)malloc(sizeof(*gwctl) + (dstcnt)*sizeof(struct sockaddr_in));
- switch( opt )
- {
- case 'A':
- cmd |= CEGW_CMD_ADD;
- break;
- case 'F':
- cmd |= CEGW_CMD_FLUSH;
- break;
- case 'L':
- cmd |= CEGW_CMD_FLUSH;
- break;
- case 'l':
- cmd |= CEGW_CMD_LISTEN;
- if( (optstr = read_iftype( optarg, &tmp )) == NULL )
- {
- perr( "listen" );
+ for (i=1; i<argc; i++) {
+ switch (i) {
+ case 1: /* can ifindex */
+ can_addr.can_family = AF_CAN;
+ tmpi = if_nametoindex(argv[i]);
+ if (tmpi == 0) {
+ perr("given can interface not found");
+ free(gwctl);
return -1;
- }
- if( tmp != IF_ETH_UDP )
- {
- fprintf( stderr, "error: -l bad input format\n" );
- return -1;
- }
- read_addr_port( optstr, &d.eth_listen_addr, &d.eth_listen_port ); /*chk*/
- break;
- case 's':
- if( read_if( optarg, &d.src_if, &d ) != 0 )
- {
- fprintf( stderr, "error: bad input format\n" );
- goto syntax_error;
- break;
}
+ can_addr.can_ifindex = tmpi;
break;
- case 'd':
- if( read_if( optarg, &d.dst_if, &d ) != 0 )
- {
- fprintf( stderr, "error: bad input format\n" );
- goto syntax_error;
- break;
+ case 2: /* listen addr */
+ udp_addr.sin_family = AF_INET;
+ if (read_addrport(argv[i], &udp_addr.sin_addr, &port) != 0) {
+ perr("listening address mismatch");
+ free(gwctl);
+ return -1;
}
+ udp_addr.sin_port = htons(port);
break;
- case '?':
- fprintf( stderr, "error: unknown option\n" );
- return -1;
- break;
- default:
- fprintf( stderr, "error: unknown option\n" );
- return -1;
+ default: /* udp destination */
+ dst = &gwctl->udp_dst[i-3];
+ dst->sin_family = AF_INET;
+ if (read_addrport(argv[i], &dst->sin_addr, &port) != 0) {
+ perr("udp destination mismatch");
+ free(gwctl);
+ return -1;
+ }
+ dst->sin_port = htons(port);
break;
- }
+ }
}
- /* prepare netlink message */
- req.nh.nlmsg_len = NLMSG_LENGTH( sizeof(struct rtmsg) );
- req.nh.nlmsg_type = RTM_DELROUTE;
- req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
- req.nh.nlmsg_seq = 0;
- req.nh.nlmsg_pid = 0; /* ? */
-
- memset( &req.rt, 0, sizeof(req.rt) );
- req.rt.rtm_family = AF_CAN;
-
- //req.rt.gwtype = CGW_TYPE_CAN_CAN;
- //req.rt.flags = 0;
+ /* prepare udp socket */
+ udp_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ if (udp_sock == -1) {
+ fprintf(stderr, "error: udp socket(..) failed\n");
+ free(gwctl);
+ return -1;
+ }
- switch( cmd )
- {
- case 0:
- fprintf( stderr, "error: command not specified\n" );
- break;
- case CEGW_CMD_ADD:
- if( cegw_add( &req, &d ) != 0 )
- {
- perr( "add" );
- return -1;
- }
- break;
- case CEGW_CMD_FLUSH:
- cegw_flush( &req, &d );
- break;
- case CEGW_CMD_LIST:
- cegw_list( &req, &d );
- break;
- case CEGW_CMD_LISTEN:
- cegw_listen( &req, &d );
- break;
- default:
- fprintf( stderr, "error: command mismatch\n" );
- break;
+ if (bind(udp_sock, (struct sockaddr *)&udp_addr, sizeof(struct sockaddr_in)) != 0) {
+ fprintf(stderr, "error: udp bind(..) failed\n");
+ free(gwctl);
+ return -1;
}
- /* send over netlink socket */
- s = socket( PF_NETLINK, SOCK_RAW, NETLINK_ROUTE ); /* chck */
-
- memset( &nladdr, 0, sizeof(nladdr) );
- nladdr.nl_family = AF_NETLINK;
- nladdr.nl_pad = 0;
- nladdr.nl_pid = 0;
- nladdr.nl_groups = 0;
+ /* prepare can socket */
+ can_sock = socket(PF_CAN, SOCK_RAW, CAN_RAW);
+ if (can_sock == -1) {
+ fprintf(stderr, "error: can socket(..) failed\n");
+ free(gwctl);
+ return -1;
+ }
- err = sendto( s, &req, req.nh.nlmsg_len, 0,
- (struct sockaddr*)&nladdr, sizeof(nladdr) );
- if( err < 0 )
- {
- perror( "netlink sendto" );
- return err;
+ if (bind(can_sock, (struct sockaddr *)&can_addr, sizeof(struct sockaddr_can)) != 0) {
+ fprintf(stderr, "error: can bind(..) failed\n");
+ free(gwctl);
+ return -1;
}
-
- /* recv */
- rsize = recv( s, &rxbuf, sizeof(rxbuf), 0 );
- if( rsize < 0 )
- {
- fprintf( stderr, "error: recv\n" );
+
+ /* send it to kernel gateway */
+ fd = open("/dev/cegw", O_RDONLY);
+ if (fd == -1) {
+ fprintf(stderr, "error: could not open device file\n");
+ free(gwctl);
return -1;
}
- nlh = (struct nlmsghdr*)rxbuf;
- if( nlh->nlmsg_type != NLMSG_ERROR )
- {
- fprintf( stderr, "error: unexpected netlink answer=%d\n", nlh->nlmsg_type );
+
+ gwctl->can_sock = can_sock;
+ gwctl->udp_sock = udp_sock;
+ gwctl->udp_dstcnt = dstcnt;
+ gwctl->udp_addrlen = sizeof(struct sockaddr_in);
+
+ if (ioctl(fd, CEGW_IOCTL_START, gwctl) != 0) {
+ perror(NULL);
+ free(gwctl);
return -1;
}
- rte = (struct nlmsgerr*)NLMSG_DATA( nlh );
- err = rte->error;
- if( err < 0 )
- fprintf( stderr, "error: netlink(%d); %s\n", err, strerror(abs(err)) );
-
+ printf("gateway successfully set and running\n");
+ free(gwctl);
+
+ /* sleep until someone kills me */
+ while (1) {
+ sleep(UINT_MAX);
+ }
+
return 0;
-syntax_error:
- return -1;
}
projects / can-eth-gw.git / blobdiff