From da76459dc21b5af2449af2d36eb95226cb186ce2 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 11:35:11 +0200 Subject: Adding upstream version 2.6.12. Signed-off-by: Daniel Baumann --- src/namespace.c | 131 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 131 insertions(+) create mode 100644 src/namespace.c (limited to 'src/namespace.c') diff --git a/src/namespace.c b/src/namespace.c new file mode 100644 index 0000000..1fc8439 --- /dev/null +++ b/src/namespace.c @@ -0,0 +1,131 @@ +#define _GNU_SOURCE + +#include +#include +#include +#include +#include +#include +#include + +#include + +#include +#include +#include +#include +#include +#include +#include + +/* Opens the namespace and returns the FD or -1 in case of error + * (check errno). + */ +static int open_named_namespace(const char *ns_name) +{ + if (chunk_printf(&trash, "/var/run/netns/%s", ns_name) < 0) + return -1; + return open(trash.area, O_RDONLY | O_CLOEXEC); +} + +static int default_namespace = -1; + +static int init_default_namespace() +{ + if (chunk_printf(&trash, "/proc/%d/ns/net", getpid()) < 0) + return -1; + default_namespace = open(trash.area, O_RDONLY | O_CLOEXEC); + return default_namespace; +} + +static struct eb_root namespace_tree_root = EB_ROOT; + +static void netns_sig_stop(struct sig_handler *sh) +{ + struct ebpt_node *node, *next; + struct netns_entry *entry; + + /* close namespace file descriptors and remove registered namespaces from the + * tree when stopping */ + node = ebpt_first(&namespace_tree_root); + while (node) { + next = ebpt_next(node); + ebpt_delete(node); + entry = container_of(node, struct netns_entry, node); + free(entry->node.key); + close(entry->fd); + node = next; + } +} + +int netns_init(void) +{ + int err_code = 0; + + /* if no namespaces have been defined in the config then + * there is no point in trying to initialize anything: + * my_socketat() will never be called with a valid namespace + * structure and thus switching back to the default namespace + * is not needed either */ + if (!eb_is_empty(&namespace_tree_root)) { + if (init_default_namespace() < 0) { + ha_alert("Failed to open the default namespace.\n"); + err_code |= ERR_ALERT | ERR_FATAL; + } + } + + signal_register_fct(0, netns_sig_stop, 0); + + return err_code; +} + +struct netns_entry* netns_store_insert(const char *ns_name) +{ + struct netns_entry *entry = NULL; + int fd = open_named_namespace(ns_name); + if (fd == -1) + goto out; + + entry = calloc(1, sizeof(*entry)); + if (!entry) + goto out; + entry->fd = fd; + entry->node.key = strdup(ns_name); + entry->name_len = strlen(ns_name); + ebis_insert(&namespace_tree_root, &entry->node); +out: + return entry; +} + +const struct netns_entry* netns_store_lookup(const char *ns_name, size_t ns_name_len) +{ + struct ebpt_node *node; + + node = ebis_lookup_len(&namespace_tree_root, ns_name, ns_name_len); + if (node) + return ebpt_entry(node, struct netns_entry, node); + else + return NULL; +} + +/* Opens a socket in the namespace described by with the parameters , + * and and returns the FD or -1 in case of error (check errno). + */ +int my_socketat(const struct netns_entry *ns, int domain, int type, int protocol) +{ + int sock; + + if (default_namespace >= 0 && ns && setns(ns->fd, CLONE_NEWNET) == -1) + return -1; + + sock = socket(domain, type, protocol); + + if (default_namespace >= 0 && ns && setns(default_namespace, CLONE_NEWNET) == -1) { + if (sock >= 0) + close(sock); + return -1; + } + return sock; +} + +REGISTER_BUILD_OPTS("Built with network namespace support."); -- cgit v1.2.3