]> rtime.felk.cvut.cz Git - can-eth-gw.git/blobdiff - utils/cegw/cegw.c
Copy IPv6 support to submodules + fixes + small enhancements
[can-eth-gw.git] / utils / cegw / cegw.c
index a0b5259ee6f89dbf7cf716c2efcb09989712cbcf..67953fe02b56d92e2010c02ca49e680d5d87e0c3 100644 (file)
@@ -1,7 +1,24 @@
+/*
+ * Copyright: (c) 2012 Czech Technical University in Prague
+ *
+ * Authors:
+ *     Radek Matějka <radek.matejka@gmail.com>
+ *     Michal Sojka  <sojkam1@fel.cvut.cz>
+ *
+ * Funded by: Volkswagen Group Research
+ *
+ * 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 <string.h>
 #include <sys/socket.h>
+#include <netdb.h>
 #include <net/if.h>
 #include <arpa/inet.h>
 #include <linux/can.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <sys/ioctl.h>
-#include "canethgw.h"
+#include <sys/types.h>
+#include <linux/can/raw.h>
+#include <linux/can/canethgw.h>
 
 unsigned int cegw_errno = 0;
 
-enum
-{
-       CEGW_ERR_UNKNOWN,
-       CEGW_ERR_COLON,
-       CEGW_ERR_UNEXLEN,
-       CEGW_ERR_ATON,
-       CEGW_ERR_PORT
-};
-
-char* cegw_errlist[] =
-{
-       [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 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"
+                              "        %s <can_if>[,filter]* <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";
+                              "        therefore cloned. Notice that there can be more udp recipients.\n"
+                              "        The can filter is specified in the same way as in candump utility.\n";
 
-static void perr(char* s)
+struct addrinfo hints = {
+       .ai_socktype = SOCK_DGRAM
+};
+
+/**
+ * readsockaddr - 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. Please note that
+ * the function modifies content of arg.
+ *
+ * @param[in]  arg   hostname:port string
+ * @param[out] addr  filled sockaddr_in structure
+ * @return 0 on success, -1 otherwise
+ */
+int readsockaddr(char *arg, struct sockaddr *addr, int ai_family)
 {
-       if (s) {
-               if (cegw_errno == 0) {
-                       fprintf(stderr, "error: %s\n", s);
+       int ret;
+       char *delim;
+       struct addrinfo *res;
 
-               } else {
-                       fprintf(stderr, "error: %s, %s\n", s, cegw_errlist[cegw_errno]);
-               }
-               return;
+       delim = strchr(arg, ':');
+
+       if (delim == NULL) {
+               fprintf(stderr, "expected ':' (<hostname>:<port>)");
+               exit(1);
+       }
+
+       *delim = '\0';
+       delim++;
+
+       hints.ai_family = ai_family;
+
+       ret = getaddrinfo(arg, delim, &hints, &res);
+       if (ret != 0) {
+               fprintf(stderr, "getaddrinfo failed: %s\n", gai_strerror(ret));
+               exit(1);
        }
 
-       fprintf(stderr, "error: %s\n", cegw_errlist[cegw_errno]);
+       memcpy(addr, res->ai_addr, res->ai_addrlen);
+
+       freeaddrinfo(res);
+       return 0;
 }
 
 /**
- * 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, -1 otherwise
+ * readfilter - reads can filter definition from nptr
  */
-int read_addrport(char* in, struct in_addr* addr, unsigned short* port)
+int readfilter(char *nptr, struct can_filter **filter, int *out_numfilter, can_err_mask_t *err_mask)
 {
-       char* delim = NULL;
-       const int addrstr_len = 16;
-       char addrstr[addrstr_len];
-       int addrlen;
+       char *ptr;
+       int numfilter;
+       struct can_filter *rfilter;
 
-       if ((delim = strchr(in, ':')) == NULL) {
-               cegw_errno = CEGW_ERR_COLON;
-               return -1;
+       numfilter = 0;
+       ptr = nptr;
+       while (ptr) {
+               numfilter++;
+               ptr++; /* hop behind the ',' */
+               ptr = strchr(ptr, ','); /* exit condition */
        }
 
-       /* get address */
-       addrlen = delim - in;
-       if (addrlen > addrstr_len) {
-               cegw_errno = CEGW_ERR_UNEXLEN;
-               return -1;
+       rfilter = malloc(numfilter * sizeof(*rfilter));
+       if (!rfilter) {
+               fprintf(stderr, "filter malloc failed");
+               exit(1);
        }
 
-       memcpy(addrstr, in, addrlen);
-       addrstr[addrlen] = '\0';
-       if (inet_aton(addrstr, addr) == 0) {
-               cegw_errno = CEGW_ERR_ATON;
-               return -1;
-       }
+       numfilter = 0;
+       *err_mask = 0;
+
+       while (nptr) {
 
-       /* get port */
-       /* ToDo: handle overflow */
-       if (sscanf(delim, ":%hu", port) != 1) {
-               cegw_errno = CEGW_ERR_PORT;
-               return -1;
+               ptr = nptr+1; /* hop behind the ',' */
+               nptr = strchr(ptr, ','); /* update exit condition */
+
+               if (sscanf(ptr, "%x:%x",
+                                       &rfilter[numfilter].can_id,
+                                       &rfilter[numfilter].can_mask) == 2) {
+                       rfilter[numfilter].can_mask &= ~CAN_ERR_FLAG;
+                       numfilter++;
+               } else if (sscanf(ptr, "%x~%x",
+                                       &rfilter[numfilter].can_id,
+                                       &rfilter[numfilter].can_mask) == 2) {
+                       rfilter[numfilter].can_id |= CAN_INV_FILTER;
+                       rfilter[numfilter].can_mask &= ~CAN_ERR_FLAG;
+                       numfilter++;
+               } else if (sscanf(ptr, "#%x", err_mask) != 1) {
+                       fprintf(stderr, "filter parsing failed");
+                       exit(1);
+               }
        }
 
+       *filter = rfilter;
+       *out_numfilter = numfilter;
        return 0;
 }
 
-int main(int argc, charargv[])
+int main(int argc, char *argv[])
 {
        int i;
        int fd;
        int tmpi;
        int dstcnt;
-       unsigned short port;
+       char *nptr;
+       int numfilter = 0;
        int udp_sock, can_sock;
-       struct sockaddr_in udp_addr;
+       int addrlen;
+       can_err_mask_t err_mask = 0;
        struct sockaddr_can can_addr;
-       struct sockaddr_in* dst = NULL;
-       struct cegw_ioctl* gwctl = NULL;
+       struct sockaddr *dst = NULL;
+       struct cegw_ioctl *gwctl = NULL;
+       struct can_filter *filter = NULL;
 
-       if (argc == 1)
-       {
+       /* udp_addr can store both - in and in6 addresses */
+       struct sockaddr_in6 udp6_addr;
+       struct sockaddr *udp_addr = (struct sockaddr *) &udp6_addr;
+
+
+       if (argc == 1 || (argc == 2 && strcmp(argv[1], "-h") == 0)) {
                printf(help_msg, argv[0], argv[0]);
                return 0;
        }
 
        if (argc < 4) {
-               perr("not enought arguments");
+               fprintf(stderr, "not enough arguments\n");
                printf(help_msg, argv[0], argv[0]);
-               /* ToDo: print usage */
-               return -1;
+               return 1;
        }
 
        dstcnt = argc-3;
-       gwctl = (struct cegw_ioctl*)malloc(sizeof(*gwctl) + (dstcnt)*sizeof(struct sockaddr_in));
 
        for (i=1; i<argc; i++) {
                switch (i) {
                        case 1: /* can ifindex */
+                               nptr = strchr(argv[i], ',');
+                               if (nptr) {
+                                       *nptr = '\0';
+                               }
+
                                can_addr.can_family = AF_CAN;
                                tmpi = if_nametoindex(argv[i]);
                                if (tmpi == 0) {
-                                       perr("given can interface not found");
-                                       free(gwctl);
-                                       return -1;
+                                       fprintf(stderr, "given can interface not found\n");
+                                       return 1;
                                }
+
                                can_addr.can_ifindex = tmpi;
                                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;
+                               readsockaddr(argv[i], udp_addr, AF_UNSPEC);
+                               switch (udp_addr->sa_family) {
+                                       case AF_INET:
+                                               addrlen = sizeof(struct sockaddr_in);
+                                               break;
+                                       case AF_INET6:
+                                               addrlen = sizeof(struct sockaddr_in6);
+                                               break;
+                                       default:
+                                               fprintf(stderr, "unexpected sockaddr family");
+                                               break;
                                }
-                               udp_addr.sin_port = htons(port);
+                               gwctl = (struct cegw_ioctl*)malloc(sizeof(*gwctl) + dstcnt*addrlen);
                                break;
                        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);
+                               dst = (struct sockaddr *)(gwctl->udp_dst + (i-3)*addrlen);
+                               readsockaddr(argv[i], dst, udp_addr->sa_family);
+
                                break;
                }
        }
 
        /* prepare udp socket */
-       udp_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+       udp_sock = socket(udp_addr->sa_family, SOCK_DGRAM, IPPROTO_UDP);
        if (udp_sock == -1) {
-               fprintf(stderr, "error: udp socket(..) failed\n");
-               free(gwctl);
-               return -1;
+               perror("udp socket(..)");
+               return 1;
        }
 
-       if (bind(udp_sock, (struct sockaddr *)&udp_addr, sizeof(struct sockaddr_in)) != 0) {
-               fprintf(stderr, "error: udp bind(..) failed\n");
-               free(gwctl);
-               return -1;
+       if (bind(udp_sock, udp_addr, addrlen) != 0) {
+               perror("bind(udp)");
+               return 1;
        }
 
        /* 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;
+               perror("can socket(..)");
+               return 1;
        }
 
        if (bind(can_sock, (struct sockaddr *)&can_addr, sizeof(struct sockaddr_can)) != 0) {
-               fprintf(stderr, "error: can bind(..) failed\n");
-               free(gwctl);
-               return -1;
+               perror("bind(can)");
+               return 1;
        }
 
+       /* can filter */
+       if (nptr)
+               readfilter(nptr, &filter, &numfilter, &err_mask);
+
+       if (err_mask)
+               setsockopt(can_sock, SOL_CAN_RAW, CAN_RAW_ERR_FILTER,
+                               &err_mask, sizeof(err_mask));
+
+       if (numfilter)
+               setsockopt(can_sock, SOL_CAN_RAW, CAN_RAW_FILTER,
+                               filter, numfilter * sizeof(struct can_filter));
+       free(filter);
+
        /* send it to kernel gateway */
-       fd = open("/dev/cegw", O_RDONLY);
+       fd = open("/dev/canethgw", O_RDONLY);
        if (fd == -1) {
-               fprintf(stderr, "error: could not open device file\n");
-               free(gwctl);
-               return -1;
+               perror("/dev/canethgw");
+               return 1;
        }
 
        gwctl->can_sock = can_sock;
        gwctl->udp_sock = udp_sock;
        gwctl->udp_dstcnt = dstcnt;
-       gwctl->udp_addrlen = sizeof(struct sockaddr_in);
+       gwctl->udp_addrlen = addrlen;
 
        if (ioctl(fd, CEGW_IOCTL_START, gwctl) != 0) {
-               perror(NULL);
-               free(gwctl);
-               return -1;
+               perror("ioctl");
+               return 1;
        }
        printf("gateway successfully set and running\n");
        free(gwctl);
 
        /* sleep until someone kills me */
-       while (1) {
-               sleep(UINT_MAX);
-       }
+       pause();
 
        return 0;
 }
-