vlan.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <linux/if_bridge.h>
#include <linux/if_ether.h>
#include <json_writer.h>
#include <string.h>

#include "libnetlink.h"
#include "br_common.h"
#include "utils.h"

static unsigned int filter_index, filter_vlan;

json_writer_t *jw_global = NULL;

static void usage(void)
{
	fprintf(stderr, "Usage: bridge vlan { add | del } vid VLAN_ID dev DEV [ pvid] [ untagged ]\n");
	fprintf(stderr, "                                                     [ self ] [ master ]\n");
	fprintf(stderr, "       bridge vlan { show } [ dev DEV ] [ vid VLAN_ID ]\n");
	exit(-1);
}

static int vlan_modify(int cmd, int argc, char **argv)
{
	struct {
		struct nlmsghdr	n;
		struct ifinfomsg	ifm;
		char			buf[1024];
	} req = {
		.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
		.n.nlmsg_flags = NLM_F_REQUEST,
		.n.nlmsg_type = cmd,
		.ifm.ifi_family = PF_BRIDGE,
	};
	char *d = NULL;
	short vid = -1;
	short vid_end = -1;
	struct rtattr *afspec;
	struct bridge_vlan_info vinfo = {};
	unsigned short flags = 0;

	while (argc > 0) {
		if (strcmp(*argv, "dev") == 0) {
			NEXT_ARG();
			d = *argv;
		} else if (strcmp(*argv, "vid") == 0) {
			char *p;

			NEXT_ARG();
			p = strchr(*argv, '-');
			if (p) {
				*p = '\0';
				p++;
				vid = atoi(*argv);
				vid_end = atoi(p);
				vinfo.flags |= BRIDGE_VLAN_INFO_RANGE_BEGIN;
			} else {
				vid = atoi(*argv);
			}
		} else if (strcmp(*argv, "self") == 0) {
			flags |= BRIDGE_FLAGS_SELF;
		} else if (strcmp(*argv, "master") == 0) {
			flags |= BRIDGE_FLAGS_MASTER;
		} else if (strcmp(*argv, "pvid") == 0) {
			vinfo.flags |= BRIDGE_VLAN_INFO_PVID;
		} else if (strcmp(*argv, "untagged") == 0) {
			vinfo.flags |= BRIDGE_VLAN_INFO_UNTAGGED;
		} else {
			if (matches(*argv, "help") == 0) {
				NEXT_ARG();
			}
		}
		argc--; argv++;
	}

	if (d == NULL || vid == -1) {
		fprintf(stderr, "Device and VLAN ID are required arguments.\n");
		return -1;
	}

	req.ifm.ifi_index = ll_name_to_index(d);
	if (req.ifm.ifi_index == 0) {
		fprintf(stderr, "Cannot find bridge device \"%s\"\n", d);
		return -1;
	}

	if (vid >= 4096) {
		fprintf(stderr, "Invalid VLAN ID \"%hu\"\n", vid);
		return -1;
	}

	if (vinfo.flags & BRIDGE_VLAN_INFO_RANGE_BEGIN) {
		if (vid_end == -1 || vid_end >= 4096 || vid >= vid_end) {
			fprintf(stderr, "Invalid VLAN range \"%hu-%hu\"\n",
				vid, vid_end);
			return -1;
		}
		if (vinfo.flags & BRIDGE_VLAN_INFO_PVID) {
			fprintf(stderr,
				"pvid cannot be configured for a vlan range\n");
			return -1;
		}
	}

	afspec = addattr_nest(&req.n, sizeof(req), IFLA_AF_SPEC);

	if (flags)
		addattr16(&req.n, sizeof(req), IFLA_BRIDGE_FLAGS, flags);

	vinfo.vid = vid;
	if (vid_end != -1) {
		/* send vlan range start */
		addattr_l(&req.n, sizeof(req), IFLA_BRIDGE_VLAN_INFO, &vinfo,
			  sizeof(vinfo));
		vinfo.flags &= ~BRIDGE_VLAN_INFO_RANGE_BEGIN;

		/* Now send the vlan range end */
		vinfo.flags |= BRIDGE_VLAN_INFO_RANGE_END;
		vinfo.vid = vid_end;
		addattr_l(&req.n, sizeof(req), IFLA_BRIDGE_VLAN_INFO, &vinfo,
			  sizeof(vinfo));
	} else {
		addattr_l(&req.n, sizeof(req), IFLA_BRIDGE_VLAN_INFO, &vinfo,
			  sizeof(vinfo));
	}

	addattr_nest_end(&req.n, afspec);

	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)
		return -1;

	return 0;
}

/* In order to use this function for both filtering and non-filtering cases
 * we need to make it a tristate:
 * return -1 - if filtering we've gone over so don't continue
 * return  0 - skip entry and continue (applies to range start or to entries
 *             which are less than filter_vlan)
 * return  1 - print the entry and continue
 */
static int filter_vlan_check(struct bridge_vlan_info *vinfo)
{
	/* if we're filtering we should stop on the first greater entry */
	if (filter_vlan && vinfo->vid > filter_vlan &&
	    !(vinfo->flags & BRIDGE_VLAN_INFO_RANGE_END))
		return -1;
	if ((vinfo->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN) ||
	    vinfo->vid < filter_vlan)
		return 0;

	return 1;
}

static void print_vlan_port(FILE *fp, int ifi_index)
{
	if (jw_global) {
		jsonw_pretty(jw_global, 1);
		jsonw_name(jw_global,
			   ll_index_to_name(ifi_index));
		jsonw_start_array(jw_global);
	} else {
		fprintf(fp, "%s",
			ll_index_to_name(ifi_index));
	}
}

static void start_json_vlan_flags_array(bool *vlan_flags)
{
	if (*vlan_flags)
		return;
	jsonw_name(jw_global, "flags");
	jsonw_start_array(jw_global);
	*vlan_flags = true;
}

static int print_vlan(const struct sockaddr_nl *who,
		      struct nlmsghdr *n,
		      void *arg)
{
	FILE *fp = arg;
	struct ifinfomsg *ifm = NLMSG_DATA(n);
	int len = n->nlmsg_len;
	struct rtattr *tb[IFLA_MAX+1];
	bool vlan_flags;

	if (n->nlmsg_type != RTM_NEWLINK) {
		fprintf(stderr, "Not RTM_NEWLINK: %08x %08x %08x\n",
			n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
		return 0;
	}

	len -= NLMSG_LENGTH(sizeof(*ifm));
	if (len < 0) {
		fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
		return -1;
	}

	if (ifm->ifi_family != AF_BRIDGE)
		return 0;

	if (filter_index && filter_index != ifm->ifi_index)
		return 0;

	parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifm), len);

	/* if AF_SPEC isn't there, vlan table is not preset for this port */
	if (!tb[IFLA_AF_SPEC]) {
		if (!filter_vlan)
			fprintf(fp, "%s\tNone\n",
				ll_index_to_name(ifm->ifi_index));
		return 0;
	} else {
		struct rtattr *i, *list = tb[IFLA_AF_SPEC];
		int rem = RTA_PAYLOAD(list);
		__u16 last_vid_start = 0;

		if (!filter_vlan)
			print_vlan_port(fp, ifm->ifi_index);

		for (i = RTA_DATA(list); RTA_OK(i, rem); i = RTA_NEXT(i, rem)) {
			struct bridge_vlan_info *vinfo;
			int vcheck_ret;

			if (i->rta_type != IFLA_BRIDGE_VLAN_INFO)
				continue;

			vinfo = RTA_DATA(i);

			if (!(vinfo->flags & BRIDGE_VLAN_INFO_RANGE_END))
				last_vid_start = vinfo->vid;
			vcheck_ret = filter_vlan_check(vinfo);
			if (vcheck_ret == -1)
				break;
			else if (vcheck_ret == 0)
				continue;

			if (filter_vlan)
				print_vlan_port(fp, ifm->ifi_index);
			if (jw_global) {
				jsonw_start_object(jw_global);
				jsonw_uint_field(jw_global, "vlan",
						 last_vid_start);
				if (vinfo->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN)
					continue;
			} else {
				fprintf(fp, "\t %hu", last_vid_start);
			}
			if (last_vid_start != vinfo->vid) {
				if (jw_global)
					jsonw_uint_field(jw_global, "vlanEnd",
							 vinfo->vid);
				else
					fprintf(fp, "-%hu", vinfo->vid);
			}
			if (vinfo->flags & BRIDGE_VLAN_INFO_PVID) {
				if (jw_global) {
					start_json_vlan_flags_array(&vlan_flags);
					jsonw_string(jw_global, "PVID");
				} else {
					fprintf(fp, " PVID");
				}
			}
			if (vinfo->flags & BRIDGE_VLAN_INFO_UNTAGGED) {
				if (jw_global) {
					start_json_vlan_flags_array(&vlan_flags);
					jsonw_string(jw_global,
						     "Egress Untagged");
				} else {
					fprintf(fp, " Egress Untagged");
				}
			}
			if (vlan_flags) {
				jsonw_end_array(jw_global);
				vlan_flags = false;
			}

			if (jw_global)
				jsonw_end_object(jw_global);
			else
				fprintf(fp, "\n");
		}
	}
	if (!filter_vlan) {
		if (jw_global)
			jsonw_end_array(jw_global);
		else
			fprintf(fp, "\n");

	}
	fflush(fp);
	return 0;
}

static int vlan_show(int argc, char **argv)
{
	char *filter_dev = NULL;

	while (argc > 0) {
		if (strcmp(*argv, "dev") == 0) {
			NEXT_ARG();
			if (filter_dev)
				duparg("dev", *argv);
			filter_dev = *argv;
		} else if (strcmp(*argv, "vid") == 0) {
			NEXT_ARG();
			if (filter_vlan)
				duparg("vid", *argv);
			filter_vlan = atoi(*argv);
		}
		argc--; argv++;
	}

	if (filter_dev) {
		if ((filter_index = if_nametoindex(filter_dev)) == 0) {
			fprintf(stderr, "Cannot find device \"%s\"\n",
			       filter_dev);
			return -1;
		}
	}

	if (rtnl_wilddump_req_filter(&rth, PF_BRIDGE, RTM_GETLINK,
				    (compress_vlans ?
				    RTEXT_FILTER_BRVLAN_COMPRESSED :
				    RTEXT_FILTER_BRVLAN)) < 0) {
		perror("Cannont send dump request");
		exit(1);
	}

	if (json_output) {
		jw_global = jsonw_new(stdout);
		if (!jw_global) {
			fprintf(stderr, "Error allocation json object\n");
			exit(1);
		}
		jsonw_start_object(jw_global);
	} else {
		printf("port\tvlan ids\n");
	}

	if (rtnl_dump_filter(&rth, print_vlan, stdout) < 0) {
		fprintf(stderr, "Dump ternminated\n");
		exit(1);
	}

	if (jw_global) {
		jsonw_end_object(jw_global);
		jsonw_destroy(&jw_global);
	}

	return 0;
}


int do_vlan(int argc, char **argv)
{
	ll_init_map(&rth);

	if (argc > 0) {
		if (matches(*argv, "add") == 0)
			return vlan_modify(RTM_SETLINK, argc-1, argv+1);
		if (matches(*argv, "delete") == 0)
			return vlan_modify(RTM_DELLINK, argc-1, argv+1);
		if (matches(*argv, "show") == 0 ||
		    matches(*argv, "lst") == 0 ||
		    matches(*argv, "list") == 0)
			return vlan_show(argc-1, argv+1);
		if (matches(*argv, "help") == 0)
			usage();
	} else
		return vlan_show(0, NULL);

	fprintf(stderr, "Command \"%s\" is unknown, try \"bridge vlan help\".\n", *argv);
	exit(-1);
}