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-rw-r--r--ip/ipmptcp.c611
1 files changed, 611 insertions, 0 deletions
diff --git a/ip/ipmptcp.c b/ip/ipmptcp.c
new file mode 100644
index 0000000..ce62ab9
--- /dev/null
+++ b/ip/ipmptcp.c
@@ -0,0 +1,611 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <linux/genetlink.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+#include <linux/mptcp.h>
+
+#include "utils.h"
+#include "ip_common.h"
+#include "json_print.h"
+#include "libgenl.h"
+#include "libnetlink.h"
+#include "ll_map.h"
+
+static void usage(void)
+{
+ fprintf(stderr,
+ "Usage: ip mptcp endpoint add ADDRESS [ dev NAME ] [ id ID ]\n"
+ " [ port NR ] [ FLAG-LIST ]\n"
+ " ip mptcp endpoint delete id ID [ ADDRESS ]\n"
+ " ip mptcp endpoint change [ id ID ] [ ADDRESS ] [ port NR ] CHANGE-OPT\n"
+ " ip mptcp endpoint show [ id ID ]\n"
+ " ip mptcp endpoint flush\n"
+ " ip mptcp limits set [ subflows NR ] [ add_addr_accepted NR ]\n"
+ " ip mptcp limits show\n"
+ " ip mptcp monitor\n"
+ "FLAG-LIST := [ FLAG-LIST ] FLAG\n"
+ "FLAG := [ signal | subflow | backup | fullmesh ]\n"
+ "CHANGE-OPT := [ backup | nobackup | fullmesh | nofullmesh ]\n");
+
+ exit(-1);
+}
+
+/* netlink socket */
+static struct rtnl_handle genl_rth = { .fd = -1 };
+static int genl_family = -1;
+
+#define MPTCP_BUFLEN 4096
+#define MPTCP_REQUEST(_req, _cmd, _flags) \
+ GENL_REQUEST(_req, MPTCP_BUFLEN, genl_family, 0, \
+ MPTCP_PM_VER, _cmd, _flags)
+
+#define MPTCP_PM_ADDR_FLAG_NONE 0x0
+
+/* Mapping from argument to address flag mask */
+static const struct {
+ const char *name;
+ unsigned long value;
+} mptcp_addr_flag_names[] = {
+ { "signal", MPTCP_PM_ADDR_FLAG_SIGNAL },
+ { "subflow", MPTCP_PM_ADDR_FLAG_SUBFLOW },
+ { "backup", MPTCP_PM_ADDR_FLAG_BACKUP },
+ { "fullmesh", MPTCP_PM_ADDR_FLAG_FULLMESH },
+ { "nobackup", MPTCP_PM_ADDR_FLAG_NONE },
+ { "nofullmesh", MPTCP_PM_ADDR_FLAG_NONE }
+};
+
+static void print_mptcp_addr_flags(unsigned int flags)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(mptcp_addr_flag_names); i++) {
+ unsigned long mask = mptcp_addr_flag_names[i].value;
+
+ if (flags & mask) {
+ print_string(PRINT_FP, NULL, "%s ",
+ mptcp_addr_flag_names[i].name);
+ print_bool(PRINT_JSON,
+ mptcp_addr_flag_names[i].name, NULL, true);
+ }
+
+ flags &= ~mask;
+ }
+
+ if (flags) {
+ /* unknown flags */
+ SPRINT_BUF(b1);
+
+ snprintf(b1, sizeof(b1), "%02x", flags);
+ print_string(PRINT_ANY, "rawflags", "rawflags %s ", b1);
+ }
+}
+
+static int get_flags(const char *arg, __u32 *flags)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(mptcp_addr_flag_names); i++) {
+ if (strcmp(arg, mptcp_addr_flag_names[i].name))
+ continue;
+
+ *flags |= mptcp_addr_flag_names[i].value;
+ return 0;
+ }
+ return -1;
+}
+
+static int mptcp_parse_opt(int argc, char **argv, struct nlmsghdr *n, int cmd)
+{
+ bool setting = cmd == MPTCP_PM_CMD_SET_FLAGS;
+ bool adding = cmd == MPTCP_PM_CMD_ADD_ADDR;
+ bool deling = cmd == MPTCP_PM_CMD_DEL_ADDR;
+ struct rtattr *attr_addr;
+ bool addr_set = false;
+ inet_prefix address;
+ bool id_set = false;
+ __u32 index = 0;
+ __u32 flags = 0;
+ __u16 port = 0;
+ __u8 id = 0;
+
+ ll_init_map(&rth);
+ while (argc > 0) {
+ if (get_flags(*argv, &flags) == 0) {
+ if (adding &&
+ (flags & MPTCP_PM_ADDR_FLAG_SIGNAL) &&
+ (flags & MPTCP_PM_ADDR_FLAG_FULLMESH))
+ invarg("flags mustn't have both signal and fullmesh", *argv);
+
+ /* allow changing the 'backup' and 'fullmesh' flags only */
+ if (setting &&
+ (flags & ~(MPTCP_PM_ADDR_FLAG_BACKUP |
+ MPTCP_PM_ADDR_FLAG_FULLMESH)))
+ invarg("invalid flags, backup and fullmesh only", *argv);
+
+ } else if (matches(*argv, "id") == 0) {
+ NEXT_ARG();
+
+ if (get_u8(&id, *argv, 0))
+ invarg("invalid ID\n", *argv);
+ id_set = true;
+ } else if (matches(*argv, "dev") == 0) {
+ const char *ifname;
+
+ NEXT_ARG();
+
+ ifname = *argv;
+
+ if (check_ifname(ifname))
+ invarg("invalid interface name\n", ifname);
+
+ index = ll_name_to_index(ifname);
+
+ if (!index)
+ invarg("device does not exist\n", ifname);
+
+ } else if (matches(*argv, "port") == 0) {
+ NEXT_ARG();
+ if (get_u16(&port, *argv, 0))
+ invarg("expected port", *argv);
+ } else if (get_addr(&address, *argv, AF_UNSPEC) == 0) {
+ addr_set = true;
+ } else {
+ invarg("unknown argument", *argv);
+ }
+ NEXT_ARG_FWD();
+ }
+
+ if (!addr_set && adding)
+ missarg("ADDRESS");
+
+ if (!id_set && deling) {
+ missarg("ID");
+ } else if (id_set && deling) {
+ if (id && addr_set)
+ invarg("invalid for non-zero id address\n", "ADDRESS");
+ else if (!id && !addr_set)
+ invarg("address is needed for deleting id 0 address\n", "ID");
+ }
+
+ if (adding && port && !(flags & MPTCP_PM_ADDR_FLAG_SIGNAL))
+ invarg("flags must have signal when using port", "port");
+
+ if (setting && id_set && port)
+ invarg("port can't be used with id", "port");
+
+ attr_addr = addattr_nest(n, MPTCP_BUFLEN,
+ MPTCP_PM_ATTR_ADDR | NLA_F_NESTED);
+ if (id_set)
+ addattr8(n, MPTCP_BUFLEN, MPTCP_PM_ADDR_ATTR_ID, id);
+ if (flags)
+ addattr32(n, MPTCP_BUFLEN, MPTCP_PM_ADDR_ATTR_FLAGS, flags);
+ if (index)
+ addattr32(n, MPTCP_BUFLEN, MPTCP_PM_ADDR_ATTR_IF_IDX, index);
+ if (port)
+ addattr16(n, MPTCP_BUFLEN, MPTCP_PM_ADDR_ATTR_PORT, port);
+ if (addr_set) {
+ int type;
+
+ addattr16(n, MPTCP_BUFLEN, MPTCP_PM_ADDR_ATTR_FAMILY,
+ address.family);
+ type = address.family == AF_INET ? MPTCP_PM_ADDR_ATTR_ADDR4 :
+ MPTCP_PM_ADDR_ATTR_ADDR6;
+ addattr_l(n, MPTCP_BUFLEN, type, &address.data,
+ address.bytelen);
+ }
+
+ addattr_nest_end(n, attr_addr);
+ return 0;
+}
+
+static int mptcp_addr_modify(int argc, char **argv, int cmd)
+{
+ MPTCP_REQUEST(req, cmd, NLM_F_REQUEST);
+ int ret;
+
+ ret = mptcp_parse_opt(argc, argv, &req.n, cmd);
+ if (ret)
+ return ret;
+
+ if (rtnl_talk(&genl_rth, &req.n, NULL) < 0)
+ return -2;
+
+ return 0;
+}
+
+static int print_mptcp_addrinfo(struct rtattr *addrinfo)
+{
+ struct rtattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1];
+ __u8 family = AF_UNSPEC, addr_attr_type;
+ const char *ifname;
+ unsigned int flags;
+ __u16 id, port;
+ int index;
+
+ parse_rtattr_nested(tb, MPTCP_PM_ADDR_ATTR_MAX, addrinfo);
+
+ open_json_object(NULL);
+ if (tb[MPTCP_PM_ADDR_ATTR_FAMILY])
+ family = rta_getattr_u8(tb[MPTCP_PM_ADDR_ATTR_FAMILY]);
+
+ addr_attr_type = family == AF_INET ? MPTCP_PM_ADDR_ATTR_ADDR4 :
+ MPTCP_PM_ADDR_ATTR_ADDR6;
+ if (tb[addr_attr_type]) {
+ print_string(PRINT_ANY, "address", "%s ",
+ format_host_rta(family, tb[addr_attr_type]));
+ }
+ if (tb[MPTCP_PM_ADDR_ATTR_PORT]) {
+ port = rta_getattr_u16(tb[MPTCP_PM_ADDR_ATTR_PORT]);
+ if (port)
+ print_uint(PRINT_ANY, "port", "port %u ", port);
+ }
+ if (tb[MPTCP_PM_ADDR_ATTR_ID]) {
+ id = rta_getattr_u8(tb[MPTCP_PM_ADDR_ATTR_ID]);
+ print_uint(PRINT_ANY, "id", "id %u ", id);
+ }
+ if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) {
+ flags = rta_getattr_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]);
+ print_mptcp_addr_flags(flags);
+ }
+ if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) {
+ index = rta_getattr_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]);
+ ifname = index ? ll_index_to_name(index) : NULL;
+
+ if (ifname)
+ print_string(PRINT_ANY, "dev", "dev %s ", ifname);
+ }
+
+ close_json_object();
+ print_string(PRINT_FP, NULL, "\n", NULL);
+ fflush(stdout);
+
+ return 0;
+}
+
+static int print_mptcp_addr(struct nlmsghdr *n, void *arg)
+{
+ struct rtattr *tb[MPTCP_PM_ATTR_MAX + 1];
+ struct genlmsghdr *ghdr;
+ struct rtattr *addrinfo;
+ int len = n->nlmsg_len;
+
+ if (n->nlmsg_type != genl_family)
+ return 0;
+
+ len -= NLMSG_LENGTH(GENL_HDRLEN);
+ if (len < 0)
+ return -1;
+
+ ghdr = NLMSG_DATA(n);
+ parse_rtattr_flags(tb, MPTCP_PM_ATTR_MAX, (void *) ghdr + GENL_HDRLEN,
+ len, NLA_F_NESTED);
+ addrinfo = tb[MPTCP_PM_ATTR_ADDR];
+ if (!addrinfo)
+ return -1;
+
+ ll_init_map(&rth);
+ return print_mptcp_addrinfo(addrinfo);
+}
+
+static int mptcp_addr_dump(void)
+{
+ MPTCP_REQUEST(req, MPTCP_PM_CMD_GET_ADDR, NLM_F_REQUEST | NLM_F_DUMP);
+
+ if (rtnl_send(&genl_rth, &req.n, req.n.nlmsg_len) < 0) {
+ perror("Cannot send show request");
+ exit(1);
+ }
+
+ new_json_obj(json);
+
+ if (rtnl_dump_filter(&genl_rth, print_mptcp_addr, stdout) < 0) {
+ fprintf(stderr, "Dump terminated\n");
+ delete_json_obj();
+ fflush(stdout);
+ return -2;
+ }
+
+ delete_json_obj();
+ fflush(stdout);
+ return 0;
+}
+
+static int mptcp_addr_show(int argc, char **argv)
+{
+ MPTCP_REQUEST(req, MPTCP_PM_CMD_GET_ADDR, NLM_F_REQUEST);
+ struct nlmsghdr *answer;
+ int ret;
+
+ if (argc <= 0)
+ return mptcp_addr_dump();
+
+ ret = mptcp_parse_opt(argc, argv, &req.n, MPTCP_PM_CMD_GET_ADDR);
+ if (ret)
+ return ret;
+
+ if (rtnl_talk(&genl_rth, &req.n, &answer) < 0)
+ return -2;
+
+ new_json_obj(json);
+ ret = print_mptcp_addr(answer, stdout);
+ delete_json_obj();
+ free(answer);
+ fflush(stdout);
+ return ret;
+}
+
+static int mptcp_addr_flush(int argc, char **argv)
+{
+ MPTCP_REQUEST(req, MPTCP_PM_CMD_FLUSH_ADDRS, NLM_F_REQUEST);
+
+ if (rtnl_talk(&genl_rth, &req.n, NULL) < 0)
+ return -2;
+
+ return 0;
+}
+
+static int mptcp_parse_limit(int argc, char **argv, struct nlmsghdr *n)
+{
+ bool set_rcv_add_addrs = false;
+ bool set_subflows = false;
+ __u32 rcv_add_addrs = 0;
+ __u32 subflows = 0;
+
+ while (argc > 0) {
+ if (matches(*argv, "subflows") == 0) {
+ NEXT_ARG();
+
+ if (get_u32(&subflows, *argv, 0))
+ invarg("invalid subflows\n", *argv);
+ set_subflows = true;
+ } else if (matches(*argv, "add_addr_accepted") == 0) {
+ NEXT_ARG();
+
+ if (get_u32(&rcv_add_addrs, *argv, 0))
+ invarg("invalid add_addr_accepted\n", *argv);
+ set_rcv_add_addrs = true;
+ } else {
+ invarg("unknown limit", *argv);
+ }
+ NEXT_ARG_FWD();
+ }
+
+ if (set_rcv_add_addrs)
+ addattr32(n, MPTCP_BUFLEN, MPTCP_PM_ATTR_RCV_ADD_ADDRS,
+ rcv_add_addrs);
+ if (set_subflows)
+ addattr32(n, MPTCP_BUFLEN, MPTCP_PM_ATTR_SUBFLOWS, subflows);
+ return set_rcv_add_addrs || set_subflows;
+}
+
+static int print_mptcp_limit(struct nlmsghdr *n, void *arg)
+{
+ struct rtattr *tb[MPTCP_PM_ATTR_MAX + 1];
+ struct genlmsghdr *ghdr;
+ int len = n->nlmsg_len;
+ __u32 val;
+
+ if (n->nlmsg_type != genl_family)
+ return 0;
+
+ len -= NLMSG_LENGTH(GENL_HDRLEN);
+ if (len < 0)
+ return -1;
+
+ ghdr = NLMSG_DATA(n);
+ parse_rtattr(tb, MPTCP_PM_ATTR_MAX, (void *) ghdr + GENL_HDRLEN, len);
+
+ open_json_object(NULL);
+ if (tb[MPTCP_PM_ATTR_RCV_ADD_ADDRS]) {
+ val = rta_getattr_u32(tb[MPTCP_PM_ATTR_RCV_ADD_ADDRS]);
+
+ print_uint(PRINT_ANY, "add_addr_accepted",
+ "add_addr_accepted %d ", val);
+ }
+
+ if (tb[MPTCP_PM_ATTR_SUBFLOWS]) {
+ val = rta_getattr_u32(tb[MPTCP_PM_ATTR_SUBFLOWS]);
+
+ print_uint(PRINT_ANY, "subflows", "subflows %d ", val);
+ }
+ print_string(PRINT_FP, NULL, "%s", "\n");
+ fflush(stdout);
+ close_json_object();
+ return 0;
+}
+
+static int mptcp_limit_get_set(int argc, char **argv, int cmd)
+{
+ bool do_get = cmd == MPTCP_PM_CMD_GET_LIMITS;
+ MPTCP_REQUEST(req, cmd, NLM_F_REQUEST);
+ struct nlmsghdr *answer;
+ int ret;
+
+ ret = mptcp_parse_limit(argc, argv, &req.n);
+ if (ret < 0)
+ return -1;
+
+ if (rtnl_talk(&genl_rth, &req.n, do_get ? &answer : NULL) < 0)
+ return -2;
+
+ ret = 0;
+ if (do_get) {
+ ret = print_mptcp_limit(answer, stdout);
+ free(answer);
+ }
+
+ return ret;
+}
+
+static const char * const event_to_str[] = {
+ [MPTCP_EVENT_CREATED] = "CREATED",
+ [MPTCP_EVENT_ESTABLISHED] = "ESTABLISHED",
+ [MPTCP_EVENT_CLOSED] = "CLOSED",
+ [MPTCP_EVENT_ANNOUNCED] = "ANNOUNCED",
+ [MPTCP_EVENT_REMOVED] = "REMOVED",
+ [MPTCP_EVENT_SUB_ESTABLISHED] = "SF_ESTABLISHED",
+ [MPTCP_EVENT_SUB_CLOSED] = "SF_CLOSED",
+ [MPTCP_EVENT_SUB_PRIORITY] = "SF_PRIO",
+};
+
+static void print_addr(const char *key, int af, struct rtattr *value)
+{
+ void *data = RTA_DATA(value);
+ char str[INET6_ADDRSTRLEN];
+
+ if (inet_ntop(af, data, str, sizeof(str)))
+ printf(" %s=%s", key, str);
+}
+
+static int mptcp_monitor_msg(struct rtnl_ctrl_data *ctrl,
+ struct nlmsghdr *n, void *arg)
+{
+ const struct genlmsghdr *ghdr = NLMSG_DATA(n);
+ struct rtattr *tb[MPTCP_ATTR_MAX + 1];
+ int len = n->nlmsg_len;
+
+ len -= NLMSG_LENGTH(GENL_HDRLEN);
+ if (len < 0)
+ return -1;
+
+ if (n->nlmsg_type != genl_family)
+ return 0;
+
+ if (timestamp)
+ print_timestamp(stdout);
+
+ if (ghdr->cmd >= ARRAY_SIZE(event_to_str)) {
+ printf("[UNKNOWN %u]\n", ghdr->cmd);
+ goto out;
+ }
+
+ if (event_to_str[ghdr->cmd] == NULL) {
+ printf("[UNKNOWN %u]\n", ghdr->cmd);
+ goto out;
+ }
+
+ printf("[%14s]", event_to_str[ghdr->cmd]);
+
+ parse_rtattr(tb, MPTCP_ATTR_MAX, (void *) ghdr + GENL_HDRLEN, len);
+
+ printf(" token=%08x", rta_getattr_u32(tb[MPTCP_ATTR_TOKEN]));
+
+ if (tb[MPTCP_ATTR_REM_ID])
+ printf(" remid=%u", rta_getattr_u8(tb[MPTCP_ATTR_REM_ID]));
+ if (tb[MPTCP_ATTR_LOC_ID])
+ printf(" locid=%u", rta_getattr_u8(tb[MPTCP_ATTR_LOC_ID]));
+
+ if (tb[MPTCP_ATTR_SADDR4])
+ print_addr("saddr4", AF_INET, tb[MPTCP_ATTR_SADDR4]);
+ if (tb[MPTCP_ATTR_DADDR4])
+ print_addr("daddr4", AF_INET, tb[MPTCP_ATTR_DADDR4]);
+ if (tb[MPTCP_ATTR_SADDR6])
+ print_addr("saddr6", AF_INET6, tb[MPTCP_ATTR_SADDR6]);
+ if (tb[MPTCP_ATTR_DADDR6])
+ print_addr("daddr6", AF_INET6, tb[MPTCP_ATTR_DADDR6]);
+ if (tb[MPTCP_ATTR_SPORT])
+ printf(" sport=%u", rta_getattr_be16(tb[MPTCP_ATTR_SPORT]));
+ if (tb[MPTCP_ATTR_DPORT])
+ printf(" dport=%u", rta_getattr_be16(tb[MPTCP_ATTR_DPORT]));
+ if (tb[MPTCP_ATTR_BACKUP])
+ printf(" backup=%d", rta_getattr_u8(tb[MPTCP_ATTR_BACKUP]));
+ if (tb[MPTCP_ATTR_ERROR])
+ printf(" error=%d", rta_getattr_u8(tb[MPTCP_ATTR_ERROR]));
+ if (tb[MPTCP_ATTR_FLAGS])
+ printf(" flags=%x", rta_getattr_u16(tb[MPTCP_ATTR_FLAGS]));
+ if (tb[MPTCP_ATTR_TIMEOUT])
+ printf(" timeout=%u", rta_getattr_u32(tb[MPTCP_ATTR_TIMEOUT]));
+ if (tb[MPTCP_ATTR_IF_IDX])
+ printf(" ifindex=%d", rta_getattr_s32(tb[MPTCP_ATTR_IF_IDX]));
+ if (tb[MPTCP_ATTR_RESET_REASON])
+ printf(" reset_reason=%u", rta_getattr_u32(tb[MPTCP_ATTR_RESET_REASON]));
+ if (tb[MPTCP_ATTR_RESET_FLAGS])
+ printf(" reset_flags=0x%x", rta_getattr_u32(tb[MPTCP_ATTR_RESET_FLAGS]));
+
+ puts("");
+out:
+ fflush(stdout);
+ return 0;
+}
+
+static int mptcp_monitor(void)
+{
+ if (genl_add_mcast_grp(&genl_rth, genl_family, MPTCP_PM_EV_GRP_NAME) < 0) {
+ perror("can't subscribe to mptcp events");
+ return 1;
+ }
+
+ if (rtnl_listen(&genl_rth, mptcp_monitor_msg, stdout) < 0)
+ return 2;
+
+ return 0;
+}
+
+int do_mptcp(int argc, char **argv)
+{
+ if (argc == 0)
+ usage();
+
+ if (matches(*argv, "help") == 0)
+ usage();
+
+ if (genl_init_handle(&genl_rth, MPTCP_PM_NAME, &genl_family))
+ exit(1);
+
+ if (matches(*argv, "endpoint") == 0) {
+ NEXT_ARG_FWD();
+ if (argc == 0)
+ return mptcp_addr_show(0, NULL);
+
+ if (matches(*argv, "add") == 0)
+ return mptcp_addr_modify(argc-1, argv+1,
+ MPTCP_PM_CMD_ADD_ADDR);
+ if (matches(*argv, "change") == 0)
+ return mptcp_addr_modify(argc-1, argv+1,
+ MPTCP_PM_CMD_SET_FLAGS);
+ if (matches(*argv, "delete") == 0)
+ return mptcp_addr_modify(argc-1, argv+1,
+ MPTCP_PM_CMD_DEL_ADDR);
+ if (matches(*argv, "show") == 0)
+ return mptcp_addr_show(argc-1, argv+1);
+ if (matches(*argv, "flush") == 0)
+ return mptcp_addr_flush(argc-1, argv+1);
+
+ goto unknown;
+ }
+
+ if (matches(*argv, "limits") == 0) {
+ NEXT_ARG_FWD();
+ if (argc == 0)
+ return mptcp_limit_get_set(0, NULL,
+ MPTCP_PM_CMD_GET_LIMITS);
+
+ if (matches(*argv, "set") == 0)
+ return mptcp_limit_get_set(argc-1, argv+1,
+ MPTCP_PM_CMD_SET_LIMITS);
+ if (matches(*argv, "show") == 0)
+ return mptcp_limit_get_set(argc-1, argv+1,
+ MPTCP_PM_CMD_GET_LIMITS);
+ }
+
+ if (matches(*argv, "monitor") == 0) {
+ NEXT_ARG_FWD();
+ if (argc == 0)
+ return mptcp_monitor();
+
+ goto unknown;
+ }
+
+unknown:
+ fprintf(stderr, "Command \"%s\" is unknown, try \"ip mptcp help\".\n",
+ *argv);
+ exit(-1);
+}