text: /*
   * ctrl.c	generic netlink controller
   *
   *		This program is free software; you can distribute 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.
   *
   * Authors:	J Hadi Salim (hadi@cyberus.ca)
   *		Johannes Berg (johannes@sipsolutions.net)
   */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <syslog.h>
  #include <fcntl.h>
  #include <sys/socket.h>
  #include <netinet/in.h>
  #include <arpa/inet.h>
  #include <string.h>
  
  #include "utils.h"
  #include "genl_utils.h"
  
  #define GENL_MAX_FAM_OPS	256
  #define GENL_MAX_FAM_GRPS	256
  
  static int usage(void)
  {
  	fprintf(stderr,"Usage: ctrl <CMD>\n" \
  		       "CMD   := get <PARMS> | list | monitor\n" \
  		       "PARMS := name <name> | id <id>\n" \
  		       "Examples:\n" \
  		       "\tctrl ls\n" \
  		       "\tctrl monitor\n" \
  		       "\tctrl get name foobar\n" \
  		       "\tctrl get id 0xF\n");
  	return -1;
  }
  
  int genl_ctrl_resolve_family(const char *family)
  {
  	struct rtnl_handle rth;
  	struct nlmsghdr *nlh;
  	struct genlmsghdr *ghdr;
  	int ret = 0;
  	struct {
  		struct nlmsghdr         n;
  		char                    buf[4096];
  	} req;
  
  	memset(&req, 0, sizeof(req));
  
  	nlh = &req.n;
  	nlh->nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
  	nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
  	nlh->nlmsg_type = GENL_ID_CTRL;
  
  	ghdr = NLMSG_DATA(&req.n);
  	ghdr->cmd = CTRL_CMD_GETFAMILY;
  
  	if (rtnl_open_byproto(&rth, 0, NETLINK_GENERIC) < 0) {
  		fprintf(stderr, "Cannot open generic netlink socket\n");
  		exit(1);
  	}
  
  	addattr_l(nlh, 128, CTRL_ATTR_FAMILY_NAME, family, strlen(family) + 1);
  
  	if (rtnl_talk(&rth, nlh, nlh, sizeof(req)) < 0) {
  		fprintf(stderr, "Error talking to the kernel\n");
  		goto errout;
  	}
  
  	{
  		struct rtattr *tb[CTRL_ATTR_MAX + 1];
  		struct genlmsghdr *ghdr = NLMSG_DATA(nlh);
  		int len = nlh->nlmsg_len;
  		struct rtattr *attrs;
  
  		if (nlh->nlmsg_type !=  GENL_ID_CTRL) {
  			fprintf(stderr, "Not a controller message, nlmsg_len=%d "
  				"nlmsg_type=0x%x\n", nlh->nlmsg_len, nlh->nlmsg_type);
  			goto errout;
  		}
  
  		if (ghdr->cmd != CTRL_CMD_NEWFAMILY) {
  			fprintf(stderr, "Unknown controller command %d\n", ghdr->cmd);
  			goto errout;
  		}
  
  		len -= NLMSG_LENGTH(GENL_HDRLEN);
  
  		if (len < 0) {
  			fprintf(stderr, "wrong controller message len %d\n", len);
  			return -1;
  		}
  
  		attrs = (struct rtattr *) ((char *) ghdr + GENL_HDRLEN);
  		parse_rtattr(tb, CTRL_ATTR_MAX, attrs, len);
  
  		if (tb[CTRL_ATTR_FAMILY_ID] == NULL) {
  			fprintf(stderr, "Missing family id TLV\n");
  			goto errout;
  		}
  
  		ret = rta_getattr_u16(tb[CTRL_ATTR_FAMILY_ID]);
  	}
  
  errout:
  	rtnl_close(&rth);
  	return ret;
  }
  
  static void print_ctrl_cmd_flags(FILE *fp, __u32 fl)
  {
  	fprintf(fp, "\n\t\tCapabilities (0x%x):\n ", fl);
  	if (!fl) {
  		fprintf(fp, "\n");
  		return;
  	}
  	fprintf(fp, "\t\t ");
  
  	if (fl & GENL_ADMIN_PERM)
  		fprintf(fp, " requires admin permission;");
  	if (fl & GENL_CMD_CAP_DO)
  		fprintf(fp, " can doit;");
  	if (fl & GENL_CMD_CAP_DUMP)
  		fprintf(fp, " can dumpit;");
  	if (fl & GENL_CMD_CAP_HASPOL)
  		fprintf(fp, " has policy");
  
  	fprintf(fp, "\n");
  }
  	
  static int print_ctrl_cmds(FILE *fp, struct rtattr *arg, __u32 ctrl_ver)
  {
  	struct rtattr *tb[CTRL_ATTR_OP_MAX + 1];
  
  	if (arg == NULL)
  		return -1;
  
  	parse_rtattr_nested(tb, CTRL_ATTR_OP_MAX, arg);
  	if (tb[CTRL_ATTR_OP_ID]) {
  		__u32 *id = RTA_DATA(tb[CTRL_ATTR_OP_ID]);
  		fprintf(fp, " ID-0x%x ",*id);
  	}
  	/* we are only gonna do this for newer version of the controller */
  	if (tb[CTRL_ATTR_OP_FLAGS] && ctrl_ver >= 0x2) {
  		__u32 *fl = RTA_DATA(tb[CTRL_ATTR_OP_FLAGS]);
  		print_ctrl_cmd_flags(fp, *fl);
  	}
  	return 0;
  
  }
  
  static int print_ctrl_grp(FILE *fp, struct rtattr *arg, __u32 ctrl_ver)
  {
  	struct rtattr *tb[CTRL_ATTR_MCAST_GRP_MAX + 1];
  
  	if (arg == NULL)
  		return -1;
  
  	parse_rtattr_nested(tb, CTRL_ATTR_MCAST_GRP_MAX, arg);
  	if (tb[2]) {
  		__u32 *id = RTA_DATA(tb[CTRL_ATTR_MCAST_GRP_ID]);
  		fprintf(fp, " ID-0x%x ",*id);
  	}
  	if (tb[1]) {
  		char *name = RTA_DATA(tb[CTRL_ATTR_MCAST_GRP_NAME]);
  		fprintf(fp, " name: %s ", name);
  	}
  	return 0;
  
  }
  
  /*
   * The controller sends one nlmsg per family
  */
  static int print_ctrl(const struct sockaddr_nl *who,
  		      struct rtnl_ctrl_data *ctrl,
  		      struct nlmsghdr *n, void *arg)
  {
  	struct rtattr *tb[CTRL_ATTR_MAX + 1];
  	struct genlmsghdr *ghdr = NLMSG_DATA(n);
  	int len = n->nlmsg_len;
  	struct rtattr *attrs;
  	FILE *fp = (FILE *) arg;
  	__u32 ctrl_v = 0x1;
  
  	if (n->nlmsg_type !=  GENL_ID_CTRL) {
  		fprintf(stderr, "Not a controller message, nlmsg_len=%d "
  			"nlmsg_type=0x%x\n", n->nlmsg_len, n->nlmsg_type);
  		return 0;
  	}
  
  	if (ghdr->cmd != CTRL_CMD_GETFAMILY &&
  	    ghdr->cmd != CTRL_CMD_DELFAMILY &&
  	    ghdr->cmd != CTRL_CMD_NEWFAMILY &&
  	    ghdr->cmd != CTRL_CMD_NEWMCAST_GRP &&
  	    ghdr->cmd != CTRL_CMD_DELMCAST_GRP) {
  		fprintf(stderr, "Unknown controller command %d\n", ghdr->cmd);
  		return 0;
  	}
  
  	len -= NLMSG_LENGTH(GENL_HDRLEN);
  
  	if (len < 0) {
  		fprintf(stderr, "wrong controller message len %d\n", len);
  		return -1;
  	}
  
  	attrs = (struct rtattr *) ((char *) ghdr + GENL_HDRLEN);
  	parse_rtattr(tb, CTRL_ATTR_MAX, attrs, len);
  
  	if (tb[CTRL_ATTR_FAMILY_NAME]) {
  		char *name = RTA_DATA(tb[CTRL_ATTR_FAMILY_NAME]);
  		fprintf(fp, "\nName: %s\n",name);
  	}
  	if (tb[CTRL_ATTR_FAMILY_ID]) {
  		__u16 *id = RTA_DATA(tb[CTRL_ATTR_FAMILY_ID]);
  		fprintf(fp, "\tID: 0x%x ",*id);
  	}
  	if (tb[CTRL_ATTR_VERSION]) {
  		__u32 *v = RTA_DATA(tb[CTRL_ATTR_VERSION]);
  		fprintf(fp, " Version: 0x%x ",*v);
  		ctrl_v = *v;
  	}
  	if (tb[CTRL_ATTR_HDRSIZE]) {
  		__u32 *h = RTA_DATA(tb[CTRL_ATTR_HDRSIZE]);
  		fprintf(fp, " header size: %d ",*h);
  	}
  	if (tb[CTRL_ATTR_MAXATTR]) {
  		__u32 *ma = RTA_DATA(tb[CTRL_ATTR_MAXATTR]);
  		fprintf(fp, " max attribs: %d ",*ma);
  	}
  	/* end of family definitions .. */
  	fprintf(fp,"\n");
  	if (tb[CTRL_ATTR_OPS]) {
  		struct rtattr *tb2[GENL_MAX_FAM_OPS];
  		int i=0;
  		parse_rtattr_nested(tb2, GENL_MAX_FAM_OPS, tb[CTRL_ATTR_OPS]);
  		fprintf(fp, "\tcommands supported: \n");
  		for (i = 0; i < GENL_MAX_FAM_OPS; i++) {
  			if (tb2[i]) {
  				fprintf(fp, "\t\t#%d: ", i);
  				if (0 > print_ctrl_cmds(fp, tb2[i], ctrl_v)) {
  					fprintf(fp, "Error printing command\n");
  				}
  				/* for next command */
  				fprintf(fp,"\n");
  			}
  		}
  
  		/* end of family::cmds definitions .. */
  		fprintf(fp,"\n");
  	}
  
  	if (tb[CTRL_ATTR_MCAST_GROUPS]) {
  		struct rtattr *tb2[GENL_MAX_FAM_GRPS + 1];
  		int i;
  
  		parse_rtattr_nested(tb2, GENL_MAX_FAM_GRPS,
  				    tb[CTRL_ATTR_MCAST_GROUPS]);
  		fprintf(fp, "\tmulticast groups:\n");
  
  		for (i = 0; i < GENL_MAX_FAM_GRPS; i++) {
  			if (tb2[i]) {
  				fprintf(fp, "\t\t#%d: ", i);
  				if (0 > print_ctrl_grp(fp, tb2[i], ctrl_v))
  					fprintf(fp, "Error printing group\n");
  				/* for next group */
  				fprintf(fp,"\n");
  			}
  		}
  
  		/* end of family::groups definitions .. */
  		fprintf(fp,"\n");
  	}
  
  	fflush(fp);
  	return 0;
  }
  
  static int print_ctrl2(const struct sockaddr_nl *who,
  		      struct nlmsghdr *n, void *arg)
  {
  	return print_ctrl(who, NULL, n, arg);
  }
  
  static int ctrl_list(int cmd, int argc, char **argv)
  {
  	struct rtnl_handle rth;
  	struct nlmsghdr *nlh;
  	struct genlmsghdr *ghdr;
  	int ret = -1;
  	char d[GENL_NAMSIZ];
  	struct {
  		struct nlmsghdr         n;
  		char                    buf[4096];
  	} req;
  
  	memset(&req, 0, sizeof(req));
  
  	nlh = &req.n;
  	nlh->nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
  	nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
  	nlh->nlmsg_type = GENL_ID_CTRL;
  
  	ghdr = NLMSG_DATA(&req.n);
  	ghdr->cmd = CTRL_CMD_GETFAMILY;
  
  	if (rtnl_open_byproto(&rth, 0, NETLINK_GENERIC) < 0) {
  		fprintf(stderr, "Cannot open generic netlink socket\n");
  		exit(1);
  	}
  
  	if (cmd == CTRL_CMD_GETFAMILY) {
  		if (argc != 2) {
  			fprintf(stderr, "Wrong number of params\n");
  			return -1;
  		}
  
  		if (matches(*argv, "name") == 0) {
  			NEXT_ARG();
  			strncpy(d, *argv, sizeof (d) - 1);
  			addattr_l(nlh, 128, CTRL_ATTR_FAMILY_NAME,
  				  d, strlen(d) + 1);
  		} else if (matches(*argv, "id") == 0) {
  			__u16 id;
  			NEXT_ARG();
  			if (get_u16(&id, *argv, 0)) {
  				fprintf(stderr, "Illegal \"id\"\n");
  				goto ctrl_done;
  			}
  
  			addattr_l(nlh, 128, CTRL_ATTR_FAMILY_ID, &id, 2);
  
  		} else {
  			fprintf(stderr, "Wrong params\n");
  			goto ctrl_done;
  		}
  
  		if (rtnl_talk(&rth, nlh, nlh, sizeof(req)) < 0) {
  			fprintf(stderr, "Error talking to the kernel\n");
  			goto ctrl_done;
  		}
  
  		if (print_ctrl2(NULL, nlh, (void *) stdout) < 0) {
  			fprintf(stderr, "Dump terminated\n");
  			goto ctrl_done;
  		}
  
  	}
  
  	if (cmd == CTRL_CMD_UNSPEC) {
  		nlh->nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST;
  		nlh->nlmsg_seq = rth.dump = ++rth.seq;
  
  		if (rtnl_send(&rth, nlh, nlh->nlmsg_len) < 0) {
  			perror("Failed to send dump request\n");
  			goto ctrl_done;
  		}
  
  		rtnl_dump_filter(&rth, print_ctrl2, stdout);
  
          }
  
  	ret = 0;
  ctrl_done:
  	rtnl_close(&rth);
  	return ret;
  }
  
  static int ctrl_listen(int argc, char **argv)
  {
  	struct rtnl_handle rth;
  
  	if (rtnl_open_byproto(&rth, nl_mgrp(GENL_ID_CTRL), NETLINK_GENERIC) < 0) {
  		fprintf(stderr, "Canot open generic netlink socket\n");
  		return -1;
  	}
  
  	if (rtnl_listen(&rth, print_ctrl, (void *) stdout) < 0)
  		return -1;
  
  	return 0;
  }
  
  static int parse_ctrl(struct genl_util *a, int argc, char **argv)
  {
  	argv++;
  	if (--argc <= 0) {
  		fprintf(stderr, "wrong controller params\n");
  		return -1;
  	}
  
  	if (matches(*argv, "monitor") == 0)
  		return ctrl_listen(argc-1, argv+1);
  	if (matches(*argv, "get") == 0)
  		return ctrl_list(CTRL_CMD_GETFAMILY, argc-1, argv+1);
  	if (matches(*argv, "list") == 0 ||
  	    matches(*argv, "show") == 0 ||
  	    matches(*argv, "lst") == 0)
  		return ctrl_list(CTRL_CMD_UNSPEC, argc-1, argv+1);
  	if (matches(*argv, "help") == 0)
  		return usage();
  
  	fprintf(stderr, "ctrl command \"%s\" is unknown, try \"ctrl help\".\n",
  		*argv);
  
  	return -1;
  }
  
  struct genl_util ctrl_genl_util = {
  	.name = "ctrl",
  	.parse_genlopt = parse_ctrl,
  	.print_genlopt = print_ctrl2,
  };
  