chiark / gitweb /
networkd: netdev - give up early when setting already set ifindex
[elogind.git] / src / network / networkd-netdev.c
index 298bf277f31e526bc44b4e38f36dd6757d905ffc..717ecdf0e5a6af5dae090486efd42435cae55f1a 100644 (file)
 ***/
 
 #include "networkd.h"
-#include "net-util.h"
+#include "network-internal.h"
 #include "path-util.h"
 #include "conf-files.h"
 #include "conf-parser.h"
 #include "list.h"
+#include "siphash24.h"
 
 #define VLANID_MAX 4094
 
@@ -67,6 +68,11 @@ void netdev_free(NetDev *netdev) {
         free(netdev->description);
         free(netdev->name);
 
+        condition_free_list(netdev->match_host);
+        condition_free_list(netdev->match_virt);
+        condition_free_list(netdev->match_kernel);
+        condition_free_list(netdev->match_arch);
+
         free(netdev);
 }
 
@@ -141,6 +147,9 @@ static int netdev_enter_ready(NetDev *netdev) {
         assert(netdev);
         assert(netdev->name);
 
+        if (netdev->state != NETDEV_STATE_CREATING)
+                return 0;
+
         netdev->state = NETDEV_STATE_READY;
 
         log_info_netdev(netdev, "netdev ready");
@@ -153,101 +162,67 @@ static int netdev_enter_ready(NetDev *netdev) {
 
         return 0;
 }
-
-static int netdev_getlink_handler(sd_rtnl *rtnl, sd_rtnl_message *m,
-                                void *userdata) {
+static int netdev_create_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
         NetDev *netdev = userdata;
-        int r, ifindex;
-
-        assert(netdev);
+        int r;
 
-        if (netdev->state == NETDEV_STATE_FAILED)
-                return 1;
+        assert(netdev->state != _NETDEV_STATE_INVALID);
 
         r = sd_rtnl_message_get_errno(m);
-        if (r < 0) {
-                log_struct_netdev(LOG_ERR, netdev,
-                                "MESSAGE=%s: could not get link: %s",
-                                netdev->name, strerror(-r),
-                                "ERRNO=%d", -r,
-                                NULL);
-                return 1;
-        }
+        if (r == -EEXIST)
+                log_debug_netdev(netdev, "netdev exists, using existing");
+        else if (r < 0) {
+                log_warning_netdev(netdev, "netdev failed: %s", strerror(-r));
+                netdev_enter_failed(netdev);
 
-        r = sd_rtnl_message_link_get_ifindex(m, &ifindex);
-        if (r < 0) {
-                log_struct_netdev(LOG_ERR, netdev,
-                                "MESSAGE=%s: could not get ifindex: %s",
-                                netdev->name, strerror(-r),
-                                "ERRNO=%d", -r,
-                                NULL);
                 return 1;
         }
 
-        r = netdev_set_ifindex(netdev, ifindex);
-        if (r < 0)
-                log_warning_netdev(netdev, "could not set ifindex to %d", ifindex);
-
         return 1;
 }
 
-static int netdev_getlink(NetDev *netdev) {
-        _cleanup_rtnl_message_unref_ sd_rtnl_message *req = NULL;
+#define HASH_KEY SD_ID128_MAKE(52,e1,45,bd,00,6f,29,96,21,c6,30,6d,83,71,04,48)
+
+static int netdev_get_mac(NetDev *netdev, struct ether_addr *mac) {
+        uint8_t result[8];
+        size_t l, sz;
+        uint8_t *v;
         int r;
 
-        assert(netdev->manager);
-        assert(netdev->manager->rtnl);
+        assert(netdev);
         assert(netdev->name);
+        assert(mac);
 
-        log_debug_netdev(netdev, "requesting netdev status");
+        l = strlen(netdev->name);
+        sz = sizeof(sd_id128_t) + l;
+        v = alloca(sz);
 
-        r = sd_rtnl_message_new_link(netdev->manager->rtnl, &req,
-                                     RTM_GETLINK, 0);
-        if (r < 0) {
-                log_error_netdev(netdev, "Could not allocate RTM_GETLINK message");
-                return r;
-        }
-
-        r = sd_rtnl_message_append_string(req, IFLA_IFNAME, netdev->name);
-        if (r < 0) {
-                log_error_netdev(netdev, "Colud not append ifname to message: %s",
-                                 strerror(-r));
-                return r;
-        }
-
-        r = sd_rtnl_call_async(netdev->manager->rtnl, req, netdev_getlink_handler,
-                               netdev, 0, NULL);
-        if (r < 0) {
-                log_error_netdev(netdev,
-                               "Could not send rtnetlink message: %s", strerror(-r));
+        /* fetch some persistent data unique to the machine */
+        r = sd_id128_get_machine((sd_id128_t*) v);
+        if (r < 0)
                 return r;
-        }
 
-        return 0;
-}
+        /* combine with some data unique (on this machine) to this
+         * netdev */
+        memcpy(v + sizeof(sd_id128_t), netdev->name, l);
 
-static int netdev_create_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        NetDev *netdev = userdata;
-        int r;
-
-        assert(netdev->state != _NETDEV_STATE_INVALID);
-
-        r = sd_rtnl_message_get_errno(m);
-        if (r == -EEXIST)
-                r = netdev_getlink(netdev);
+        /* Let's hash the host machine ID plus the container name. We
+         * use a fixed, but originally randomly created hash key here. */
+        siphash24(result, v, sz, HASH_KEY.bytes);
 
-        if (r < 0) {
-                log_warning_netdev(netdev, "netdev failed: %s", strerror(-r));
-                netdev_enter_failed(netdev);
+        assert_cc(ETH_ALEN <= sizeof(result));
+        memcpy(mac->ether_addr_octet, result, ETH_ALEN);
 
-                return 1;
-        }
+        /* see eth_random_addr in the kernel */
+        mac->ether_addr_octet[0] &= 0xfe;        /* clear multicast bit */
+        mac->ether_addr_octet[0] |= 0x02;        /* set local assignment bit (IEEE802) */
 
-        return 1;
+        return 0;
 }
 
 static int netdev_create(NetDev *netdev, Link *link, sd_rtnl_message_handler_t callback) {
         _cleanup_rtnl_message_unref_ sd_rtnl_message *req = NULL;
+        struct ether_addr mac;
         const char *kind;
         int r;
 
@@ -258,6 +233,12 @@ static int netdev_create(NetDev *netdev, Link *link, sd_rtnl_message_handler_t c
         assert(netdev->manager);
         assert(netdev->manager->rtnl);
 
+        r = netdev_get_mac(netdev, &mac);
+        if (r < 0) {
+                log_error("Failed to generate predictable MAC address for %s", netdev->name);
+                return r;
+        }
+
         r = sd_rtnl_message_new_link(netdev->manager->rtnl, &req, RTM_NEWLINK, 0);
         if (r < 0) {
                 log_error_netdev(netdev,
@@ -284,6 +265,14 @@ static int netdev_create(NetDev *netdev, Link *link, sd_rtnl_message_handler_t c
                 return r;
         }
 
+        r = sd_rtnl_message_append_ether_addr(req, IFLA_ADDRESS, &mac);
+        if (r < 0) {
+                log_error_netdev(netdev,
+                                 "Colud not append IFLA_ADDRESS attribute: %s",
+                                 strerror(-r));
+                return r;
+        }
+
         r = sd_rtnl_message_open_container(req, IFLA_LINKINFO);
         if (r < 0) {
                 log_error_netdev(netdev,
@@ -298,52 +287,42 @@ static int netdev_create(NetDev *netdev, Link *link, sd_rtnl_message_handler_t c
                 return -EINVAL;
         }
 
-        r = sd_rtnl_message_append_string(req, IFLA_INFO_KIND, kind);
+        r = sd_rtnl_message_open_container_union(req, IFLA_INFO_DATA, kind);
         if (r < 0) {
                 log_error_netdev(netdev,
-                                 "Could not append IFLA_INFO_KIND attribute: %s",
-                                 strerror(-r));
+                                 "Could not open IFLA_INFO_DATA container: %s",
+                                  strerror(-r));
                 return r;
         }
 
-        if (netdev->vlanid <= VLANID_MAX || netdev->macvlan_mode != _NETDEV_MACVLAN_MODE_INVALID) {
-                r = sd_rtnl_message_open_container(req, IFLA_INFO_DATA);
+        if (netdev->vlanid <= VLANID_MAX) {
+                r = sd_rtnl_message_append_u16(req, IFLA_VLAN_ID, netdev->vlanid);
                 if (r < 0) {
                         log_error_netdev(netdev,
-                                         "Could not open IFLA_INFO_DATA container: %s",
+                                         "Could not append IFLA_VLAN_ID attribute: %s",
                                          strerror(-r));
                         return r;
                 }
+        }
 
-                if (netdev->vlanid <= VLANID_MAX) {
-                        r = sd_rtnl_message_append_u16(req, IFLA_VLAN_ID, netdev->vlanid);
-                        if (r < 0) {
-                                log_error_netdev(netdev,
-                                                 "Could not append IFLA_VLAN_ID attribute: %s",
-                                                 strerror(-r));
-                                return r;
-                        }
-                }
-
-                if (netdev->macvlan_mode != _NETDEV_MACVLAN_MODE_INVALID) {
-                        r = sd_rtnl_message_append_u32(req, IFLA_MACVLAN_MODE, netdev->macvlan_mode);
-                        if (r < 0) {
-                                log_error_netdev(netdev,
-                                                 "Could not append IFLA_MACVLAN_MODE attribute: %s",
-                                                 strerror(-r));
-                                return r;
-                        }
-                }
-
-                r = sd_rtnl_message_close_container(req);
-                if (r < 0) {
-                        log_error_netdev(netdev,
-                                         "Could not close IFLA_INFO_DATA container %s",
-                                         strerror(-r));
+        if (netdev->macvlan_mode != _NETDEV_MACVLAN_MODE_INVALID) {
+        r = sd_rtnl_message_append_u32(req, IFLA_MACVLAN_MODE, netdev->macvlan_mode);
+        if (r < 0) {
+                log_error_netdev(netdev,
+                                 "Could not append IFLA_MACVLAN_MODE attribute: %s",
+                                 strerror(-r));
                         return r;
                 }
         }
 
+        r = sd_rtnl_message_close_container(req);
+        if (r < 0) {
+                log_error_netdev(netdev,
+                                 "Could not close IFLA_INFO_DATA container %s",
+                                 strerror(-r));
+                return r;
+        }
+
         r = sd_rtnl_message_close_container(req);
         if (r < 0) {
                 log_error_netdev(netdev,
@@ -392,15 +371,93 @@ int netdev_enslave(NetDev *netdev, Link *link, sd_rtnl_message_handler_t callbac
         return 0;
 }
 
-int netdev_set_ifindex(NetDev *netdev, int ifindex) {
+int netdev_set_ifindex(NetDev *netdev, sd_rtnl_message *message) {
+        uint16_t type;
+        const char *kind;
+        char *received_kind;
+        char *received_name;
+        int r, ifindex;
+
         assert(netdev);
-        assert(ifindex > 0);
+        assert(message);
+
+        r = sd_rtnl_message_get_type(message, &type);
+        if (r < 0) {
+                log_error_netdev(netdev, "Could not get rtnl message type");
+                return r;
+        }
+
+        if (type != RTM_NEWLINK) {
+                log_error_netdev(netdev, "Can not set ifindex from unexpected rtnl message type");
+                return -EINVAL;
+        }
+
+        r = sd_rtnl_message_link_get_ifindex(message, &ifindex);
+        if (r < 0) {
+                log_error_netdev(netdev, "Could not get ifindex: %s", strerror(-r));
+                netdev_enter_failed(netdev);
+                return r;
+        } else if (ifindex <= 0) {
+                log_error_netdev(netdev, "Got invalid ifindex: %d", ifindex);
+                netdev_enter_failed(netdev);
+                return r;
+        }
+
 
         if (netdev->ifindex > 0) {
-                if (netdev->ifindex == ifindex)
-                        return 0;
-                else
+                if (netdev->ifindex != ifindex) {
+                        log_error_netdev(netdev, "Could not set ifindex to %d, already set to %d",
+                                         ifindex, netdev->ifindex);
+                        netdev_enter_failed(netdev);
                         return -EEXIST;
+                } else
+                        /* ifindex already set to the same for this netdev */
+                        return 0;
+        }
+
+        r = sd_rtnl_message_read_string(message, IFLA_IFNAME, &received_name);
+        if (r < 0) {
+                log_error_netdev(netdev, "Could not get IFNAME");
+                return r;
+        }
+
+        if (!streq(netdev->name, received_name)) {
+                log_error_netdev(netdev, "Received newlink with wrong IFNAME %s",
+                                 received_name);
+                netdev_enter_failed(netdev);
+                return r;
+        }
+
+        r = sd_rtnl_message_enter_container(message, IFLA_LINKINFO);
+        if (r < 0) {
+                log_error_netdev(netdev, "Could not get LINKINFO");
+                return r;
+        }
+
+        r = sd_rtnl_message_read_string(message, IFLA_INFO_KIND, &received_kind);
+        if (r < 0) {
+                log_error_netdev(netdev, "Could not get KIND");
+                return r;
+        }
+
+        r = sd_rtnl_message_exit_container(message);
+        if (r < 0) {
+                log_error_netdev(netdev, "Could not exit container");
+                return r;
+        }
+
+        kind = netdev_kind_to_string(netdev->kind);
+        if (!kind) {
+                log_error_netdev(netdev, "Could not get kind");
+                netdev_enter_failed(netdev);
+                return -EINVAL;
+        }
+
+        if (!streq(kind, received_kind)) {
+                log_error_netdev(netdev, "Received newlink with wrong KIND %s, "
+                                 "expected %s", received_kind, kind);
+                netdev_enter_failed(netdev);
+                return r;
         }
 
         netdev->ifindex = ifindex;
@@ -423,7 +480,7 @@ static int netdev_load_one(Manager *manager, const char *filename) {
                 if (errno == ENOENT)
                         return 0;
                 else
-                        return errno;
+                        return -errno;
         }
 
         netdev = new0(NetDev, 1);