diff --git a/doc/lxc.container.conf.sgml.in b/doc/lxc.container.conf.sgml.in index 316327985..287bc8e51 100644 --- a/doc/lxc.container.conf.sgml.in +++ b/doc/lxc.container.conf.sgml.in @@ -1519,6 +1519,20 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + + + + + + + + A hook to be run in the host's namespace after the + container has been setup, and immediately before starting + the container init. + + + + diff --git a/src/lxc/conf.c b/src/lxc/conf.c index b6dfa915c..0b5a9e260 100644 --- a/src/lxc/conf.c +++ b/src/lxc/conf.c @@ -236,7 +236,8 @@ extern int memfd_create(const char *name, unsigned int flags); char *lxchook_names[NUM_LXC_HOOKS] = {"pre-start", "pre-mount", "mount", "autodev", "start", "stop", - "post-stop", "clone", "destroy"}; + "post-stop", "clone", "destroy", + "start-host"}; struct mount_opt { char *name; @@ -3285,6 +3286,8 @@ int run_lxc_hooks(const char *name, char *hook, struct lxc_conf *conf, if (strcmp(hook, "pre-start") == 0) which = LXCHOOK_PRESTART; + else if (strcmp(hook, "start-host") == 0) + which = LXCHOOK_START_HOST; else if (strcmp(hook, "pre-mount") == 0) which = LXCHOOK_PREMOUNT; else if (strcmp(hook, "mount") == 0) diff --git a/src/lxc/conf.h b/src/lxc/conf.h index 946ae4a23..1bc02dc4f 100644 --- a/src/lxc/conf.h +++ b/src/lxc/conf.h @@ -228,6 +228,7 @@ enum lxchooks { LXCHOOK_POSTSTOP, LXCHOOK_CLONE, LXCHOOK_DESTROY, + LXCHOOK_START_HOST, NUM_LXC_HOOKS }; diff --git a/src/lxc/confile.c b/src/lxc/confile.c index ed83d5dc8..1beb9c7b4 100644 --- a/src/lxc/confile.c +++ b/src/lxc/confile.c @@ -155,6 +155,7 @@ static struct lxc_config_t config[] = { { "lxc.hook.destroy", false, set_config_hooks, get_config_hooks, clr_config_hooks, }, { "lxc.hook.mount", false, set_config_hooks, get_config_hooks, clr_config_hooks, }, { "lxc.hook.post-stop", false, set_config_hooks, get_config_hooks, clr_config_hooks, }, + { "lxc.hook.start-host", false, set_config_hooks, get_config_hooks, clr_config_hooks, }, { "lxc.hook.pre-start", false, set_config_hooks, get_config_hooks, clr_config_hooks, }, { "lxc.hook.pre-mount", false, set_config_hooks, get_config_hooks, clr_config_hooks, }, { "lxc.hook.start", false, set_config_hooks, get_config_hooks, clr_config_hooks, }, @@ -980,6 +981,8 @@ static int set_config_hooks(const char *key, const char *value, if (strcmp(key + 9, "pre-start") == 0) return add_hook(lxc_conf, LXCHOOK_PRESTART, copy); + else if (strcmp(key + 9, "start-host") == 0) + return add_hook(lxc_conf, LXCHOOK_START_HOST, copy); else if (strcmp(key + 9, "pre-mount") == 0) return add_hook(lxc_conf, LXCHOOK_PREMOUNT, copy); else if (strcmp(key + 9, "autodev") == 0) @@ -4445,6 +4448,7 @@ int lxc_list_subkeys(struct lxc_conf *conf, const char *key, char *retv, strprint(retv, inlen, "post-stop\n"); strprint(retv, inlen, "pre-mount\n"); strprint(retv, inlen, "pre-start\n"); + strprint(retv, inlen, "start-host\n"); strprint(retv, inlen, "start\n"); strprint(retv, inlen, "stop\n"); } else if (!strcmp(key, "lxc.cap")) { diff --git a/src/lxc/start.c b/src/lxc/start.c index b838e579d..d8460403e 100644 --- a/src/lxc/start.c +++ b/src/lxc/start.c @@ -1165,6 +1165,7 @@ static int lxc_spawn(struct lxc_handler *handler) { int i, flags, ret; const char *name = handler->name; + char pidstr[20]; bool wants_to_map_ids; int saved_ns_fd[LXC_NS_MAX]; struct lxc_list *id_map; @@ -1355,13 +1356,23 @@ static int lxc_spawn(struct lxc_handler *handler) cgroup_disconnect(); cgroups_connected = false; + snprintf(pidstr, 20, "%d", handler->pid); + if (setenv("LXC_PID", pidstr, 1)) + SYSERROR("Failed to set environment variable: LXC_PID=%s.", pidstr); + + /* Run any host-side start hooks */ + if (run_lxc_hooks(name, "start-host", handler->conf, handler->lxcpath, NULL)) { + ERROR("Failed to run lxc.hook.start-host for container \"%s\".", name); + return -1; + } + /* Tell the child to complete its initialization and wait for it to exec * or return an error. (The child will never return - * LXC_SYNC_POST_CGROUP+1. It will either close the sync pipe, causing + * LXC_SYNC_READY_START+1. It will either close the sync pipe, causing * lxc_sync_barrier_child to return success, or return a different * value, causing us to error out). */ - if (lxc_sync_barrier_child(handler, LXC_SYNC_POST_CGROUP)) + if (lxc_sync_barrier_child(handler, LXC_SYNC_READY_START)) return -1; if (lxc_network_recv_name_and_ifindex_from_child(handler) < 0) { diff --git a/src/lxc/sync.h b/src/lxc/sync.h index 744db613e..5c0fb3431 100644 --- a/src/lxc/sync.h +++ b/src/lxc/sync.h @@ -32,7 +32,7 @@ enum { LXC_SYNC_CGROUP, LXC_SYNC_CGROUP_UNSHARE, LXC_SYNC_CGROUP_LIMITS, - LXC_SYNC_POST_CGROUP, + LXC_SYNC_READY_START, LXC_SYNC_RESTART, LXC_SYNC_POST_RESTART, LXC_SYNC_ERROR = -1 /* Used to report errors from another process */