ipnetns: enable to dump nsid conversion table

This patch enables to dump/get nsid from a netns into another netns.

Example:
$ ./test.sh
+ ip netns add foo
+ ip netns add bar
+ touch /var/run/netns/init_net
+ mount --bind /proc/1/ns/net /var/run/netns/init_net
+ ip netns set init_net 11
+ ip netns set foo 12
+ ip netns set bar 13
+ ip netns
init_net (id: 11)
bar (id: 13)
foo (id: 12)
+ ip -n foo netns set init_net 21
+ ip -n foo netns set foo 22
+ ip -n foo netns set bar 23
+ ip -n foo netns
init_net (id: 21)
bar (id: 23)
foo (id: 22)
+ ip -n bar netns set init_net 31
+ ip -n bar netns set foo 32
+ ip -n bar netns set bar 33
+ ip -n bar netns
init_net (id: 31)
bar (id: 33)
foo (id: 32)
+ ip netns list-id target-nsid 12
nsid 21 current-nsid 11 (iproute2 netns name: init_net)
nsid 22 current-nsid 12 (iproute2 netns name: foo)
nsid 23 current-nsid 13 (iproute2 netns name: bar)
+ ip -n foo netns list-id target-nsid 21
nsid 11 current-nsid 21 (iproute2 netns name: init_net)
nsid 12 current-nsid 22 (iproute2 netns name: foo)
nsid 13 current-nsid 23 (iproute2 netns name: bar)
+ ip -n bar netns list-id target-nsid 33 nsid 32
nsid 32 current-nsid 32 (iproute2 netns name: foo)
+ ip -n bar netns list-id target-nsid 31 nsid 32
nsid 12 current-nsid 32 (iproute2 netns name: foo)
+ ip netns list-id nsid 13
nsid 13 (iproute2 netns name: bar)

CC: Petr Oros <poros@redhat.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Tested-by: Petr Oros <poros@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>

diff --git a/include/libnetlink.h b/include/libnetlink.h
index 311cf3fc90f883f47c7d65b15faabb1ca0ed6451..8ebdc6d3d03efc1dd37864508ab879cb4b446d15 100644 (file)
--- a/include/libnetlink.h
+++ b/include/libnetlink.h
@@ -71,8 +71,6 @@ int rtnl_mdbdump_req(struct rtnl_handle *rth, int family)
        __attribute__((warn_unused_result));
 int rtnl_netconfdump_req(struct rtnl_handle *rth, int family)
        __attribute__((warn_unused_result));
-int rtnl_nsiddump_req(struct rtnl_handle *rth, int family)
-       __attribute__((warn_unused_result));
 
 int rtnl_linkdump_req(struct rtnl_handle *rth, int fam)
        __attribute__((warn_unused_result));
@@ -85,6 +83,9 @@ int rtnl_linkdump_req_filter_fn(struct rtnl_handle *rth, int fam,
 int rtnl_fdb_linkdump_req_filter_fn(struct rtnl_handle *rth,
                                    req_filter_fn_t filter_fn)
        __attribute__((warn_unused_result));
+int rtnl_nsiddump_req_filter_fn(struct rtnl_handle *rth, int family,
+                               req_filter_fn_t filter_fn)
+       __attribute__((warn_unused_result));
 int rtnl_statsdump_req_filter(struct rtnl_handle *rth, int fam, __u32 filt_mask)
        __attribute__((warn_unused_result));
 int rtnl_dump_request(struct rtnl_handle *rth, int type, void *req,

diff --git a/ip/ip_common.h b/ip/ip_common.h
index cd916ec87c2653b57d04478bda6d01b3956cac60..879287e3e5060a981778f5b7b22ae82a58fdcade 100644 (file)
--- a/ip/ip_common.h
+++ b/ip/ip_common.h
@@ -24,6 +24,7 @@ struct link_filter {
        int master;
        char *kind;
        char *slave_kind;
+       int target_nsid;
 };
 
 int get_operstate(const char *name);

diff --git a/ip/ipnetns.c b/ip/ipnetns.c
index a883f210d7ba45fcd2090b0e09c0991e1e984416..20110ef0f58ee571b826a3e1ea1d16f5a93fbba8 100644 (file)
--- a/ip/ipnetns.c
+++ b/ip/ipnetns.c
@@ -36,7 +36,7 @@ static int usage(void)
                "       ip netns pids NAME\n"
                "       ip [-all] netns exec [NAME] cmd ...\n"
                "       ip netns monitor\n"
-               "       ip netns list-id\n"
+               "       ip netns list-id [target-nsid POSITIVE-INT] [nsid POSITIVE-INT]\n"
                "NETNSID := auto | POSITIVE-INT\n");
        exit(-1);
 }
@@ -46,6 +46,7 @@ static struct rtnl_handle rtnsh = { .fd = -1 };
 
 static int have_rtnl_getnsid = -1;
 static int saved_netns = -1;
+static struct link_filter filter;
 
 static int ipnetns_accept_msg(struct rtnl_ctrl_data *ctrl,
                              struct nlmsghdr *n, void *arg)
@@ -294,7 +295,7 @@ int print_nsid(struct nlmsghdr *n, void *arg)
        FILE *fp = (FILE *)arg;
        struct nsid_cache *c;
        char name[NAME_MAX];
-       int nsid;
+       int nsid, current;
 
        if (n->nlmsg_type != RTM_NEWNSID && n->nlmsg_type != RTM_DELNSID)
                return 0;
@@ -317,9 +318,22 @@ int print_nsid(struct nlmsghdr *n, void *arg)
                print_bool(PRINT_ANY, "deleted", "Deleted ", true);
 
        nsid = rta_getattr_u32(tb[NETNSA_NSID]);
-       print_uint(PRINT_ANY, "nsid", "nsid %u ", nsid);
+       if (nsid < 0)
+               print_string(PRINT_ANY, "nsid", "nsid %s ", "not-assigned");
+       else
+               print_uint(PRINT_ANY, "nsid", "nsid %u ", nsid);
+
+       if (tb[NETNSA_CURRENT_NSID]) {
+               current = rta_getattr_u32(tb[NETNSA_CURRENT_NSID]);
+               if (current < 0)
+                       print_string(PRINT_ANY, "current-nsid",
+                                    "current-nsid %s ", "not-assigned");
+               else
+                       print_uint(PRINT_ANY, "current-nsid",
+                                  "current-nsid %u ", current);
+       }
 
-       c = netns_map_get_by_nsid(nsid);
+       c = netns_map_get_by_nsid(tb[NETNSA_CURRENT_NSID] ? current : nsid);
        if (c != NULL) {
                print_string(PRINT_ANY, "name",
                             "(iproute2 netns name: %s)", c->name);
@@ -340,15 +354,106 @@ int print_nsid(struct nlmsghdr *n, void *arg)
        return 0;
 }
 
+static int get_netnsid_from_netnsid(int nsid)
+{
+       struct {
+               struct nlmsghdr n;
+               struct rtgenmsg g;
+               char            buf[1024];
+       } req = {
+               .n.nlmsg_len = NLMSG_LENGTH(NLMSG_ALIGN(sizeof(struct rtgenmsg))),
+               .n.nlmsg_flags = NLM_F_REQUEST,
+               .n.nlmsg_type = RTM_GETNSID,
+               .g.rtgen_family = AF_UNSPEC,
+       };
+       struct nlmsghdr *answer;
+       int err;
+
+       netns_nsid_socket_init();
+
+       err = addattr32(&req.n, sizeof(req), NETNSA_NSID, nsid);
+       if (err)
+               return err;
+
+       if (filter.target_nsid >= 0) {
+               err = addattr32(&req.n, sizeof(req), NETNSA_TARGET_NSID,
+                               filter.target_nsid);
+               if (err)
+                       return err;
+       }
+
+       if (rtnl_talk(&rtnsh, &req.n, &answer) < 0)
+               return -2;
+
+       /* Validate message and parse attributes */
+       if (answer->nlmsg_type == NLMSG_ERROR)
+               goto err_out;
+
+       new_json_obj(json);
+       err = print_nsid(answer, stdout);
+       delete_json_obj();
+err_out:
+       free(answer);
+       return err;
+}
+
+static int netns_filter_req(struct nlmsghdr *nlh, int reqlen)
+{
+       int err;
+
+       if (filter.target_nsid >= 0) {
+               err = addattr32(nlh, reqlen, NETNSA_TARGET_NSID,
+                               filter.target_nsid);
+               if (err)
+                       return err;
+       }
+
+       return 0;
+}
+
 static int netns_list_id(int argc, char **argv)
 {
+       int nsid = -1;
+
        if (!ipnetns_have_nsid()) {
                fprintf(stderr,
                        "RTM_GETNSID is not supported by the kernel.\n");
                return -ENOTSUP;
        }
 
-       if (rtnl_nsiddump_req(&rth, AF_UNSPEC) < 0) {
+       filter.target_nsid = -1;
+       while (argc > 0) {
+               if (strcmp(*argv, "target-nsid") == 0) {
+                       if (filter.target_nsid >= 0)
+                               duparg("target-nsid", *argv);
+                       NEXT_ARG();
+
+                       if (get_integer(&filter.target_nsid, *argv, 0))
+                               invarg("\"target-nsid\" value is invalid\n",
+                                      *argv);
+                       else if (filter.target_nsid < 0)
+                               invarg("\"target-nsid\" value should be >= 0\n",
+                                      argv[1]);
+               } else if (strcmp(*argv, "nsid") == 0) {
+                       if (nsid >= 0)
+                               duparg("nsid", *argv);
+                       NEXT_ARG();
+
+                       if (get_integer(&nsid, *argv, 0))
+                               invarg("\"nsid\" value is invalid\n", *argv);
+                       else if (nsid < 0)
+                               invarg("\"nsid\" value should be >= 0\n",
+                                      argv[1]);
+               } else
+                       usage();
+               argc--; argv++;
+       }
+
+       if (nsid >= 0)
+               return get_netnsid_from_netnsid(nsid);
+
+       if (rtnl_nsiddump_req_filter_fn(&rth, AF_UNSPEC,
+                                       netns_filter_req) < 0) {
                perror("Cannot send dump request");
                exit(1);
        }

diff --git a/lib/libnetlink.c b/lib/libnetlink.c
index 8c490f896326f3257c383d861049f696bbae6852..6ce8b199f4419e55441532d6d25fb5a074b114e1 100644 (file)
--- a/lib/libnetlink.c
+++ b/lib/libnetlink.c
@@ -438,12 +438,13 @@ int rtnl_netconfdump_req(struct rtnl_handle *rth, int family)
        return send(rth->fd, &req, sizeof(req), 0);
 }
 
-int rtnl_nsiddump_req(struct rtnl_handle *rth, int family)
+int rtnl_nsiddump_req_filter_fn(struct rtnl_handle *rth, int family,
+                               req_filter_fn_t filter_fn)
 {
        struct {
                struct nlmsghdr nlh;
                struct rtgenmsg rtm;
-               char buf[0] __aligned(NLMSG_ALIGNTO);
+               char buf[1024];
        } req = {
                .nlh.nlmsg_len = NLMSG_LENGTH(NLMSG_ALIGN(sizeof(struct rtgenmsg))),
                .nlh.nlmsg_type = RTM_GETNSID,
@@ -451,8 +452,16 @@ int rtnl_nsiddump_req(struct rtnl_handle *rth, int family)
                .nlh.nlmsg_seq = rth->dump = ++rth->seq,
                .rtm.rtgen_family = family,
        };
+       int err;
 
-       return send(rth->fd, &req, sizeof(req), 0);
+       if (!filter_fn)
+               return -EINVAL;
+
+       err = filter_fn(&req.nlh, sizeof(req));
+       if (err)
+               return err;
+
+       return send(rth->fd, &req, req.nlh.nlmsg_len, 0);
 }
 
 static int __rtnl_linkdump_req(struct rtnl_handle *rth, int family)