diff options
Diffstat (limited to '')
| -rw-r--r-- | src/monitor.c | 1014 |
1 files changed, 1014 insertions, 0 deletions
diff --git a/src/monitor.c b/src/monitor.c new file mode 100644 index 0000000..82762a0 --- /dev/null +++ b/src/monitor.c @@ -0,0 +1,1014 @@ +/* + * Copyright (c) 2015 Arturo Borrero Gonzalez <arturo@netfilter.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 (or any + * later) as published by the Free Software Foundation. + */ + +#include <nft.h> + +#include <fcntl.h> +#include <errno.h> +#include <libmnl/libmnl.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <inttypes.h> + +#include <libnftnl/table.h> +#include <libnftnl/trace.h> +#include <libnftnl/chain.h> +#include <libnftnl/expr.h> +#include <libnftnl/object.h> +#include <libnftnl/set.h> +#include <libnftnl/flowtable.h> +#include <libnftnl/udata.h> +#include <libnftnl/ruleset.h> +#include <libnftnl/common.h> +#include <linux/netfilter/nfnetlink.h> +#include <linux/netfilter/nf_tables.h> +#include <linux/netfilter.h> + +#include <nftables.h> +#include <netlink.h> +#include <mnl.h> +#include <expression.h> +#include <statement.h> +#include <gmputil.h> +#include <utils.h> +#include <erec.h> +#include <iface.h> +#include <json.h> + +enum { + NFT_OF_EVENT_ADD, + NFT_OF_EVENT_INSERT, + NFT_OF_EVENT_DEL, + NFT_OF_EVENT_CREATE, +}; + +#define nft_mon_print(monh, ...) nft_print(&monh->ctx->nft->output, __VA_ARGS__) + +struct nftnl_table *netlink_table_alloc(const struct nlmsghdr *nlh) +{ + struct nftnl_table *nlt; + + nlt = nftnl_table_alloc(); + if (nlt == NULL) + memory_allocation_error(); + if (nftnl_table_nlmsg_parse(nlh, nlt) < 0) + netlink_abi_error(); + + return nlt; +} + +struct nftnl_chain *netlink_chain_alloc(const struct nlmsghdr *nlh) +{ + struct nftnl_chain *nlc; + + nlc = nftnl_chain_alloc(); + if (nlc == NULL) + memory_allocation_error(); + if (nftnl_chain_nlmsg_parse(nlh, nlc) < 0) + netlink_abi_error(); + + return nlc; +} + +struct nftnl_set *netlink_set_alloc(const struct nlmsghdr *nlh) +{ + struct nftnl_set *nls; + + nls = nftnl_set_alloc(); + if (nls == NULL) + memory_allocation_error(); + if (nftnl_set_nlmsg_parse(nlh, nls) < 0) + netlink_abi_error(); + + return nls; +} + +static struct nftnl_set *netlink_setelem_alloc(const struct nlmsghdr *nlh) +{ + struct nftnl_set *nls; + + nls = nftnl_set_alloc(); + if (nls == NULL) + memory_allocation_error(); + if (nftnl_set_elems_nlmsg_parse(nlh, nls) < 0) + netlink_abi_error(); + + return nls; +} + +struct nftnl_rule *netlink_rule_alloc(const struct nlmsghdr *nlh) +{ + struct nftnl_rule *nlr; + + nlr = nftnl_rule_alloc(); + if (nlr == NULL) + memory_allocation_error(); + if (nftnl_rule_nlmsg_parse(nlh, nlr) < 0) + netlink_abi_error(); + + return nlr; +} + +struct nftnl_obj *netlink_obj_alloc(const struct nlmsghdr *nlh) +{ + struct nftnl_obj *nlo; + + nlo = nftnl_obj_alloc(); + if (nlo == NULL) + memory_allocation_error(); + if (nftnl_obj_nlmsg_parse(nlh, nlo) < 0) + netlink_abi_error(); + + return nlo; +} + +static uint32_t netlink_msg2nftnl_of(uint32_t type, uint16_t flags) +{ + switch (type) { + case NFT_MSG_NEWRULE: + if (flags & NLM_F_APPEND) + return NFT_OF_EVENT_ADD; + else + return NFT_OF_EVENT_INSERT; + case NFT_MSG_NEWTABLE: + case NFT_MSG_NEWCHAIN: + case NFT_MSG_NEWSET: + case NFT_MSG_NEWSETELEM: + case NFT_MSG_NEWOBJ: + case NFT_MSG_NEWFLOWTABLE: + if (flags & NLM_F_EXCL) + return NFT_OF_EVENT_CREATE; + else + return NFT_OF_EVENT_ADD; + case NFT_MSG_DELTABLE: + case NFT_MSG_DELCHAIN: + case NFT_MSG_DELSET: + case NFT_MSG_DELSETELEM: + case NFT_MSG_DELRULE: + case NFT_MSG_DELOBJ: + case NFT_MSG_DELFLOWTABLE: + return NFTNL_OF_EVENT_DEL; + } + + return 0; +} + +static const char *nftnl_of2cmd(uint32_t of) +{ + switch (of) { + case NFT_OF_EVENT_ADD: + return "add"; + case NFT_OF_EVENT_CREATE: + return "create"; + case NFT_OF_EVENT_INSERT: + return "insert"; + case NFT_OF_EVENT_DEL: + return "delete"; + default: + return "???"; + } +} + +static const char *netlink_msg2cmd(uint32_t type, uint16_t flags) +{ + return nftnl_of2cmd(netlink_msg2nftnl_of(type, flags)); +} + +static void nlr_for_each_set(struct nftnl_rule *nlr, + void (*cb)(struct set *s, void *data), + void *data, struct nft_cache *cache) +{ + struct nftnl_expr_iter *nlrei; + struct nftnl_expr *nlre; + const char *set_name, *table; + const char *name; + struct set *s; + uint32_t family; + + nlrei = nftnl_expr_iter_create(nlr); + if (nlrei == NULL) + memory_allocation_error(); + + family = nftnl_rule_get_u32(nlr, NFTNL_RULE_FAMILY); + table = nftnl_rule_get_str(nlr, NFTNL_RULE_TABLE); + + nlre = nftnl_expr_iter_next(nlrei); + while (nlre != NULL) { + name = nftnl_expr_get_str(nlre, NFTNL_EXPR_NAME); + if (strcmp(name, "lookup") != 0) + goto next; + + set_name = nftnl_expr_get_str(nlre, NFTNL_EXPR_LOOKUP_SET); + s = set_lookup_global(family, table, set_name, cache); + if (s == NULL) + goto next; + + cb(s, data); +next: + nlre = nftnl_expr_iter_next(nlrei); + } + nftnl_expr_iter_destroy(nlrei); +} + +static int netlink_events_table_cb(const struct nlmsghdr *nlh, int type, + struct netlink_mon_handler *monh) +{ + struct nftnl_table *nlt; + struct table *t; + const char *cmd; + + nlt = netlink_table_alloc(nlh); + t = netlink_delinearize_table(monh->ctx, nlt); + cmd = netlink_msg2cmd(type, nlh->nlmsg_flags); + + switch (monh->format) { + case NFTNL_OUTPUT_DEFAULT: + nft_mon_print(monh, "%s table ", cmd); + + nft_mon_print(monh, "%s %s", family2str(t->handle.family), + t->handle.table.name); + + if (t->flags & TABLE_F_DORMANT) + nft_mon_print(monh, " { flags dormant; }"); + + if (nft_output_handle(&monh->ctx->nft->output)) + nft_mon_print(monh, " # handle %" PRIu64 "", + t->handle.handle.id); + nft_mon_print(monh, "\n"); + break; + case NFTNL_OUTPUT_JSON: + monitor_print_table_json(monh, cmd, t); + if (!nft_output_echo(&monh->ctx->nft->output)) + nft_mon_print(monh, "\n"); + break; + } + table_free(t); + nftnl_table_free(nlt); + return MNL_CB_OK; +} + +static int netlink_events_chain_cb(const struct nlmsghdr *nlh, int type, + struct netlink_mon_handler *monh) +{ + struct nftnl_chain *nlc; + struct chain *c; + const char *cmd; + + nlc = netlink_chain_alloc(nlh); + c = netlink_delinearize_chain(monh->ctx, nlc); + cmd = netlink_msg2cmd(type, nlh->nlmsg_flags); + + switch (monh->format) { + case NFTNL_OUTPUT_DEFAULT: + nft_mon_print(monh, "%s ", cmd); + + switch (type) { + case NFT_MSG_NEWCHAIN: + chain_print_plain(c, &monh->ctx->nft->output); + break; + case NFT_MSG_DELCHAIN: + if (c->dev_array_len > 0) + chain_print_plain(c, &monh->ctx->nft->output); + else + nft_mon_print(monh, "chain %s %s %s", + family2str(c->handle.family), + c->handle.table.name, + c->handle.chain.name); + break; + } + nft_mon_print(monh, "\n"); + break; + case NFTNL_OUTPUT_JSON: + monitor_print_chain_json(monh, cmd, c); + if (!nft_output_echo(&monh->ctx->nft->output)) + nft_mon_print(monh, "\n"); + break; + } + chain_free(c); + nftnl_chain_free(nlc); + return MNL_CB_OK; +} + +static int netlink_events_set_cb(const struct nlmsghdr *nlh, int type, + struct netlink_mon_handler *monh) +{ + struct nftnl_set *nls; + const char *family, *cmd; + struct set *set; + uint32_t flags; + + nls = netlink_set_alloc(nlh); + flags = nftnl_set_get_u32(nls, NFTNL_SET_FLAGS); + if (set_is_anonymous(flags)) + goto out; + + set = netlink_delinearize_set(monh->ctx, nls); + if (set == NULL) { + nftnl_set_free(nls); + return MNL_CB_ERROR; + } + family = family2str(set->handle.family); + cmd = netlink_msg2cmd(type, nlh->nlmsg_flags); + + switch (monh->format) { + case NFTNL_OUTPUT_DEFAULT: + nft_mon_print(monh, "%s ", cmd); + + switch (type) { + case NFT_MSG_NEWSET: + set_print_plain(set, &monh->ctx->nft->output); + break; + case NFT_MSG_DELSET: + nft_mon_print(monh, "set %s %s %s", family, + set->handle.table.name, + set->handle.set.name); + break; + } + nft_mon_print(monh, "\n"); + break; + case NFTNL_OUTPUT_JSON: + monitor_print_set_json(monh, cmd, set); + if (!nft_output_echo(&monh->ctx->nft->output)) + nft_mon_print(monh, "\n"); + break; + } + set_free(set); +out: + nftnl_set_free(nls); + return MNL_CB_OK; +} + +/* returns true if the event should be ignored (i.e. null element) */ +static bool netlink_event_ignore_range_event(struct nftnl_set_elem *nlse) +{ + uint32_t flags = 0; + + if (nftnl_set_elem_is_set(nlse, NFTNL_SET_ELEM_FLAGS)) + flags = nftnl_set_elem_get_u32(nlse, NFTNL_SET_ELEM_FLAGS); + if (!(flags & NFT_SET_ELEM_INTERVAL_END)) + return false; + + if (nftnl_set_elem_get_u32(nlse, NFTNL_SET_ELEM_KEY) != 0) + return false; + + return true; +} + +static bool set_elem_is_open_interval(struct expr *elem) +{ + switch (elem->etype) { + case EXPR_SET_ELEM: + return elem->elem_flags & NFTNL_SET_ELEM_F_INTERVAL_OPEN; + case EXPR_MAPPING: + return set_elem_is_open_interval(elem->left); + default: + return false; + } +} + +/* returns true if the we cached the range element */ +static bool netlink_event_range_cache(struct set *cached_set, + struct set *dummyset) +{ + struct expr *elem; + + /* not an interval ? */ + if (!(cached_set->flags & NFT_SET_INTERVAL)) + return false; + + /* if cache exists, dummyset must contain the other end of the range */ + if (cached_set->rg_cache) { + compound_expr_add(dummyset->init, cached_set->rg_cache); + cached_set->rg_cache = NULL; + goto out_decompose; + } + + /* don't cache half-open range elements */ + elem = list_entry(dummyset->init->expressions.prev, struct expr, list); + if (!set_elem_is_open_interval(elem)) { + cached_set->rg_cache = expr_clone(elem); + return true; + } + +out_decompose: + interval_map_decompose(dummyset->init); + return false; +} + +static int netlink_events_setelem_cb(const struct nlmsghdr *nlh, int type, + struct netlink_mon_handler *monh) +{ + struct nftnl_set_elems_iter *nlsei; + struct nftnl_set_elem *nlse; + struct nftnl_set *nls; + struct set *dummyset; + struct set *set; + const char *setname, *table, *cmd; + uint32_t family; + + nls = netlink_setelem_alloc(nlh); + table = nftnl_set_get_str(nls, NFTNL_SET_TABLE); + setname = nftnl_set_get_str(nls, NFTNL_SET_NAME); + family = nftnl_set_get_u32(nls, NFTNL_SET_FAMILY); + cmd = netlink_msg2cmd(type, nlh->nlmsg_flags); + + set = set_lookup_global(family, table, setname, &monh->ctx->nft->cache); + if (set == NULL) { + fprintf(stderr, "W: Received event for an unknown set.\n"); + goto out; + } + + if (set_is_anonymous(set->flags)) + goto out; + + /* we want to 'delinearize' the set_elem, but don't + * modify the original cached set. This path is only + * used by named sets, so use a dummy set. + */ + dummyset = set_alloc(monh->loc); + handle_merge(&dummyset->handle, &set->handle); + dummyset->key = expr_clone(set->key); + if (set->data) + dummyset->data = expr_clone(set->data); + dummyset->flags = set->flags; + dummyset->init = set_expr_alloc(monh->loc, set); + + nlsei = nftnl_set_elems_iter_create(nls); + if (nlsei == NULL) + memory_allocation_error(); + + nlse = nftnl_set_elems_iter_next(nlsei); + while (nlse != NULL) { + if (netlink_event_ignore_range_event(nlse)) { + set_free(dummyset); + nftnl_set_elems_iter_destroy(nlsei); + goto out; + } + if (netlink_delinearize_setelem(nlse, dummyset, + &monh->ctx->nft->cache) < 0) { + set_free(dummyset); + nftnl_set_elems_iter_destroy(nlsei); + goto out; + } + nlse = nftnl_set_elems_iter_next(nlsei); + } + nftnl_set_elems_iter_destroy(nlsei); + + if (netlink_event_range_cache(set, dummyset)) { + set_free(dummyset); + goto out; + } + + switch (monh->format) { + case NFTNL_OUTPUT_DEFAULT: + nft_mon_print(monh, "%s element %s %s %s ", + cmd, family2str(family), table, setname); + expr_print(dummyset->init, &monh->ctx->nft->output); + nft_mon_print(monh, "\n"); + break; + case NFTNL_OUTPUT_JSON: + dummyset->handle.family = family; + dummyset->handle.set.name = setname; + dummyset->handle.table.name = table; + monitor_print_element_json(monh, cmd, dummyset); + /* prevent set_free() from trying to free those */ + dummyset->handle.set.name = NULL; + dummyset->handle.table.name = NULL; + if (!nft_output_echo(&monh->ctx->nft->output)) + nft_mon_print(monh, "\n"); + break; + } + set_free(dummyset); +out: + nftnl_set_free(nls); + return MNL_CB_OK; +} + +static int netlink_events_obj_cb(const struct nlmsghdr *nlh, int type, + struct netlink_mon_handler *monh) +{ + const char *family, *cmd; + struct nftnl_obj *nlo; + struct obj *obj; + + nlo = netlink_obj_alloc(nlh); + + obj = netlink_delinearize_obj(monh->ctx, nlo); + if (!obj) { + nftnl_obj_free(nlo); + return MNL_CB_ERROR; + } + family = family2str(obj->handle.family); + cmd = netlink_msg2cmd(type, nlh->nlmsg_flags); + + switch (monh->format) { + case NFTNL_OUTPUT_DEFAULT: + nft_mon_print(monh, "%s ", cmd); + + switch (type) { + case NFT_MSG_NEWOBJ: + obj_print_plain(obj, &monh->ctx->nft->output); + break; + case NFT_MSG_DELOBJ: + nft_mon_print(monh, "%s %s %s %s", + obj_type_name(obj->type), + family, + obj->handle.table.name, + obj->handle.obj.name); + break; + } + nft_mon_print(monh, "\n"); + break; + case NFTNL_OUTPUT_JSON: + monitor_print_obj_json(monh, cmd, obj); + if (!nft_output_echo(&monh->ctx->nft->output)) + nft_mon_print(monh, "\n"); + break; + } + obj_free(obj); + nftnl_obj_free(nlo); + return MNL_CB_OK; +} + +static void rule_map_decompose_cb(struct set *s, void *data) +{ + if (!set_is_anonymous(s->flags)) + return; + + if (set_is_non_concat_range(s)) + interval_map_decompose(s->init); + else if (set_is_interval(s->flags)) + concat_range_aggregate(s->init); +} + +static int netlink_events_rule_cb(const struct nlmsghdr *nlh, int type, + struct netlink_mon_handler *monh) +{ + const char *family, *cmd; + struct nftnl_rule *nlr; + struct rule *r; + + nlr = netlink_rule_alloc(nlh); + r = netlink_delinearize_rule(monh->ctx, nlr); + if (!r) { + fprintf(stderr, "W: Received event for an unknown table.\n"); + goto out_free_nlr; + } + nlr_for_each_set(nlr, rule_map_decompose_cb, NULL, + &monh->ctx->nft->cache); + cmd = netlink_msg2cmd(type, nlh->nlmsg_flags); + + switch (monh->format) { + case NFTNL_OUTPUT_DEFAULT: + family = family2str(r->handle.family); + + nft_mon_print(monh, "%s rule %s %s %s ", + cmd, + family, + r->handle.table.name, + r->handle.chain.name); + if (r->handle.position.id) { + nft_mon_print(monh, "handle %" PRIu64" ", + r->handle.position.id); + } + switch (type) { + case NFT_MSG_NEWRULE: + rule_print(r, &monh->ctx->nft->output); + + break; + case NFT_MSG_DELRULE: + nft_mon_print(monh, "handle %" PRIu64, + r->handle.handle.id); + break; + } + nft_mon_print(monh, "\n"); + break; + case NFTNL_OUTPUT_JSON: + monitor_print_rule_json(monh, cmd, r); + if (!nft_output_echo(&monh->ctx->nft->output)) + nft_mon_print(monh, "\n"); + break; + } + rule_free(r); +out_free_nlr: + nftnl_rule_free(nlr); + return MNL_CB_OK; +} + +static void netlink_events_cache_addtable(struct netlink_mon_handler *monh, + const struct nlmsghdr *nlh) +{ + struct nftnl_table *nlt; + struct table *t; + + nlt = netlink_table_alloc(nlh); + t = netlink_delinearize_table(monh->ctx, nlt); + nftnl_table_free(nlt); + + table_cache_add(t, &monh->ctx->nft->cache); +} + +static void netlink_events_cache_deltable(struct netlink_mon_handler *monh, + const struct nlmsghdr *nlh) +{ + struct nftnl_table *nlt; + struct table *t; + struct handle h; + + nlt = netlink_table_alloc(nlh); + h.family = nftnl_table_get_u32(nlt, NFTNL_TABLE_FAMILY); + h.table.name = nftnl_table_get_str(nlt, NFTNL_TABLE_NAME); + + t = table_cache_find(&monh->ctx->nft->cache.table_cache, + h.table.name, h.family); + if (t == NULL) + goto out; + + table_cache_del(t); + table_free(t); +out: + nftnl_table_free(nlt); +} + +static void netlink_events_cache_addset(struct netlink_mon_handler *monh, + const struct nlmsghdr *nlh) +{ + struct netlink_ctx set_tmpctx; + struct nftnl_set *nls; + struct table *t; + struct set *s; + LIST_HEAD(msgs); + + memset(&set_tmpctx, 0, sizeof(set_tmpctx)); + init_list_head(&set_tmpctx.list); + init_list_head(&msgs); + set_tmpctx.nft = monh->ctx->nft; + set_tmpctx.msgs = &msgs; + + nls = netlink_set_alloc(nlh); + s = netlink_delinearize_set(&set_tmpctx, nls); + if (s == NULL) + goto out; + s->init = set_expr_alloc(monh->loc, s); + + t = table_cache_find(&monh->ctx->nft->cache.table_cache, + s->handle.table.name, s->handle.family); + if (t == NULL) { + fprintf(stderr, "W: Unable to cache set: table not found.\n"); + set_free(s); + goto out; + } + + if (nft_output_echo(&monh->ctx->nft->output) && + !set_is_anonymous(s->flags)) { + set_free(s); + goto out; + } + + set_cache_add(s, t); +out: + nftnl_set_free(nls); +} + +static void netlink_events_cache_addsetelem(struct netlink_mon_handler *monh, + const struct nlmsghdr *nlh) +{ + struct nftnl_set_elems_iter *nlsei; + struct nftnl_set_elem *nlse; + struct nftnl_set *nls; + struct set *set; + const char *table, *setname; + uint32_t family; + + nls = netlink_setelem_alloc(nlh); + family = nftnl_set_get_u32(nls, NFTNL_SET_FAMILY); + table = nftnl_set_get_str(nls, NFTNL_SET_TABLE); + setname = nftnl_set_get_str(nls, NFTNL_SET_NAME); + + set = set_lookup_global(family, table, setname, &monh->ctx->nft->cache); + if (set == NULL) { + fprintf(stderr, + "W: Unable to cache set_elem. Set not found.\n"); + goto out; + } + + if (nft_output_echo(&monh->ctx->nft->output) && + !set_is_anonymous(set->flags)) + goto out; + + nlsei = nftnl_set_elems_iter_create(nls); + if (nlsei == NULL) + memory_allocation_error(); + + nlse = nftnl_set_elems_iter_next(nlsei); + while (nlse != NULL) { + if (netlink_delinearize_setelem(nlse, set, + &monh->ctx->nft->cache) < 0) { + fprintf(stderr, + "W: Unable to cache set_elem. " + "Delinearize failed.\n"); + nftnl_set_elems_iter_destroy(nlsei); + goto out; + } + nlse = nftnl_set_elems_iter_next(nlsei); + } + nftnl_set_elems_iter_destroy(nlsei); +out: + nftnl_set_free(nls); +} + +static void netlink_events_cache_delset_cb(struct set *s, + void *data) +{ + set_cache_del(s); + set_free(s); +} + +static void netlink_events_cache_delsets(struct netlink_mon_handler *monh, + const struct nlmsghdr *nlh) +{ + struct nftnl_rule *nlr = netlink_rule_alloc(nlh); + + nlr_for_each_set(nlr, netlink_events_cache_delset_cb, NULL, + &monh->ctx->nft->cache); + nftnl_rule_free(nlr); +} + +static void netlink_events_cache_addobj(struct netlink_mon_handler *monh, + const struct nlmsghdr *nlh) +{ + struct netlink_ctx obj_tmpctx; + struct nftnl_obj *nlo; + struct table *t; + struct obj *obj; + LIST_HEAD(msgs); + + memset(&obj_tmpctx, 0, sizeof(obj_tmpctx)); + init_list_head(&obj_tmpctx.list); + init_list_head(&msgs); + obj_tmpctx.msgs = &msgs; + + nlo = netlink_obj_alloc(nlh); + obj = netlink_delinearize_obj(&obj_tmpctx, nlo); + if (obj == NULL) + goto out; + + t = table_cache_find(&monh->ctx->nft->cache.table_cache, + obj->handle.table.name, obj->handle.family); + if (t == NULL) { + fprintf(stderr, "W: Unable to cache object: table not found.\n"); + obj_free(obj); + goto out; + } + + obj_cache_add(obj, t); +out: + nftnl_obj_free(nlo); +} + +static void netlink_events_cache_delobj(struct netlink_mon_handler *monh, + const struct nlmsghdr *nlh) +{ + struct nftnl_obj *nlo; + const char *name; + struct obj *obj; + struct handle h; + struct table *t; + uint32_t type; + + nlo = netlink_obj_alloc(nlh); + h.family = nftnl_obj_get_u32(nlo, NFTNL_OBJ_FAMILY); + h.table.name = nftnl_obj_get_str(nlo, NFTNL_OBJ_TABLE); + + name = nftnl_obj_get_str(nlo, NFTNL_OBJ_NAME); + type = nftnl_obj_get_u32(nlo, NFTNL_OBJ_TYPE); + h.handle.id = nftnl_obj_get_u64(nlo, NFTNL_OBJ_HANDLE); + + t = table_cache_find(&monh->ctx->nft->cache.table_cache, + h.table.name, h.family); + if (t == NULL) { + fprintf(stderr, "W: Unable to cache object: table not found.\n"); + goto out; + } + + obj = obj_cache_find(t, name, type); + if (obj == NULL) { + fprintf(stderr, "W: Unable to find object in cache\n"); + goto out; + } + + obj_cache_del(obj); + obj_free(obj); +out: + nftnl_obj_free(nlo); +} + +static void netlink_events_cache_update(struct netlink_mon_handler *monh, + const struct nlmsghdr *nlh, int type) +{ + if (nft_output_echo(&monh->ctx->nft->output) && + type != NFT_MSG_NEWSET && type != NFT_MSG_NEWSETELEM) + return; + + switch (type) { + case NFT_MSG_NEWTABLE: + netlink_events_cache_addtable(monh, nlh); + break; + case NFT_MSG_DELTABLE: + netlink_events_cache_deltable(monh, nlh); + break; + case NFT_MSG_NEWSET: + netlink_events_cache_addset(monh, nlh); + break; + case NFT_MSG_NEWSETELEM: + netlink_events_cache_addsetelem(monh, nlh); + break; + case NFT_MSG_DELRULE: + /* there are no notification for anon-set deletion */ + netlink_events_cache_delsets(monh, nlh); + break; + case NFT_MSG_NEWOBJ: + netlink_events_cache_addobj(monh, nlh); + break; + case NFT_MSG_DELOBJ: + netlink_events_cache_delobj(monh, nlh); + break; + } +} + +/* only those which could be useful listening to events */ +static const char *const nftnl_msg_types[NFT_MSG_MAX] = { + [NFT_MSG_NEWTABLE] = "NFT_MSG_NEWTABLE", + [NFT_MSG_DELTABLE] = "NFT_MSG_DELTABLE", + [NFT_MSG_NEWCHAIN] = "NFT_MSG_NEWCHAIN", + [NFT_MSG_DELCHAIN] = "NFT_MSG_DELCHAIN", + [NFT_MSG_NEWSET] = "NFT_MSG_NEWSET", + [NFT_MSG_DELSET] = "NFT_MSG_DELSET", + [NFT_MSG_NEWSETELEM] = "NFT_MSG_NEWSETELEM", + [NFT_MSG_DELSETELEM] = "NFT_MSG_DELSETELEM", + [NFT_MSG_NEWRULE] = "NFT_MSG_NEWRULE", + [NFT_MSG_DELRULE] = "NFT_MSG_DELRULE", + [NFT_MSG_TRACE] = "NFT_MSG_TRACE", + [NFT_MSG_NEWGEN] = "NFT_MSG_NEWGEN", + [NFT_MSG_NEWOBJ] = "NFT_MSG_NEWOBJ", + [NFT_MSG_DELOBJ] = "NFT_MSG_DELOBJ", +}; + +static const char *nftnl_msgtype2str(uint16_t type) +{ + if (type >= NFT_MSG_MAX || !nftnl_msg_types[type]) + return "unknown"; + + return nftnl_msg_types[type]; +} + +static void netlink_events_debug(uint16_t type, unsigned int debug_mask) +{ + if (!(debug_mask & NFT_DEBUG_NETLINK)) + return; + + printf("netlink event: %s\n", nftnl_msgtype2str(type)); +} + +static int netlink_events_newgen_cb(const struct nlmsghdr *nlh, int type, + struct netlink_mon_handler *monh) +{ + const struct nlattr *attr; + char name[256] = ""; + int genid = -1, pid = -1; + + if (monh->format != NFTNL_OUTPUT_DEFAULT) + return MNL_CB_OK; + + mnl_attr_for_each(attr, nlh, sizeof(struct nfgenmsg)) { + switch (mnl_attr_get_type(attr)) { + case NFTA_GEN_ID: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + break; + genid = ntohl(mnl_attr_get_u32(attr)); + break; + case NFTA_GEN_PROC_NAME: + if (mnl_attr_validate(attr, MNL_TYPE_NUL_STRING) < 0) + break; + snprintf(name, sizeof(name), "%s", mnl_attr_get_str(attr)); + break; + case NFTA_GEN_PROC_PID: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + break; + pid = ntohl(mnl_attr_get_u32(attr)); + break; + } + } + if (genid >= 0) { + nft_mon_print(monh, "# new generation %d", genid); + if (pid >= 0) + nft_mon_print(monh, " by process %d (%s)", pid, name); + + nft_mon_print(monh, "\n"); + } + + return MNL_CB_OK; +} + +static int netlink_events_cb(const struct nlmsghdr *nlh, void *data) +{ + int ret = MNL_CB_OK; + uint16_t type = NFNL_MSG_TYPE(nlh->nlmsg_type); + struct netlink_mon_handler *monh = (struct netlink_mon_handler *)data; + + netlink_events_debug(type, monh->ctx->nft->debug_mask); + netlink_events_cache_update(monh, nlh, type); + + if (!(monh->monitor_flags & (1 << type))) + return ret; + + switch (type) { + case NFT_MSG_NEWTABLE: + case NFT_MSG_DELTABLE: + ret = netlink_events_table_cb(nlh, type, monh); + break; + case NFT_MSG_NEWCHAIN: + case NFT_MSG_DELCHAIN: + ret = netlink_events_chain_cb(nlh, type, monh); + break; + case NFT_MSG_NEWSET: + case NFT_MSG_DELSET: /* nft {add|delete} set */ + ret = netlink_events_set_cb(nlh, type, monh); + break; + case NFT_MSG_NEWSETELEM: + case NFT_MSG_DELSETELEM: /* nft {add|delete} element */ + ret = netlink_events_setelem_cb(nlh, type, monh); + break; + case NFT_MSG_NEWRULE: + case NFT_MSG_DELRULE: + ret = netlink_events_rule_cb(nlh, type, monh); + break; + case NFT_MSG_TRACE: + ret = netlink_events_trace_cb(nlh, type, monh); + break; + case NFT_MSG_NEWOBJ: + case NFT_MSG_DELOBJ: + ret = netlink_events_obj_cb(nlh, type, monh); + break; + case NFT_MSG_NEWGEN: + ret = netlink_events_newgen_cb(nlh, type, monh); + break; + } + + return ret; +} + +int netlink_echo_callback(const struct nlmsghdr *nlh, void *data) +{ + struct netlink_cb_data *nl_cb_data = data; + struct netlink_ctx *ctx = nl_cb_data->nl_ctx; + struct nft_ctx *nft = ctx->nft; + + struct netlink_mon_handler echo_monh = { + .format = NFTNL_OUTPUT_DEFAULT, + .ctx = ctx, + .loc = &netlink_location, + .monitor_flags = 0xffffffff, + }; + + if (!nft_output_echo(&echo_monh.ctx->nft->output)) + return MNL_CB_OK; + + if (nft_output_json(&nft->output)) { + if (nft->json_root) + return json_events_cb(nlh, &echo_monh); + if (!nft->json_echo) + json_alloc_echo(nft); + echo_monh.format = NFTNL_OUTPUT_JSON; + } + + return netlink_events_cb(nlh, &echo_monh); +} + +int netlink_monitor(struct netlink_mon_handler *monhandler, + struct mnl_socket *nf_sock) +{ + int group; + + if (monhandler->monitor_flags & (1 << NFT_MSG_TRACE)) { + group = NFNLGRP_NFTRACE; + if (mnl_socket_setsockopt(nf_sock, NETLINK_ADD_MEMBERSHIP, + &group, sizeof(int)) < 0) + return -1; + } + if (monhandler->monitor_flags & ~(1 << NFT_MSG_TRACE)) { + group = NFNLGRP_NFTABLES; + if (mnl_socket_setsockopt(nf_sock, NETLINK_ADD_MEMBERSHIP, + &group, sizeof(int)) < 0) + return -1; + } + + return mnl_nft_event_listener(nf_sock, monhandler->ctx->nft->debug_mask, + &monhandler->ctx->nft->output, + netlink_events_cb, monhandler); +} |