NetBSD/sys/net/npf/npf_ctl.c

880 lines
20 KiB
C

/*-
* Copyright (c) 2009-2020 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This material is based upon work partially supported by The
* NetBSD Foundation under a contract with Mindaugas Rasiukevicius.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* NPF device control.
*
* Implementation of (re)loading, construction of tables and rules.
* NPF nvlist(3) consumer.
*/
#ifdef _KERNEL
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: npf_ctl.c,v 1.60 2020/05/30 14:16:56 rmind Exp $");
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/kmem.h>
#include <net/bpf.h>
#endif
#include "npf_impl.h"
#include "npf_conn.h"
#define NPF_ERR_DEBUG(e) \
nvlist_add_string((e), "source-file", __FILE__); \
nvlist_add_number((e), "source-line", __LINE__);
static int __noinline
npf_mk_params(npf_t *npf, const nvlist_t *req, nvlist_t *resp, bool set)
{
const nvlist_t *params;
int type, error, val;
const char *name;
void *cookie;
params = dnvlist_get_nvlist(req, "params", NULL);
if (params == NULL) {
return 0;
}
cookie = NULL;
while ((name = nvlist_next(params, &type, &cookie)) != NULL) {
if (type != NV_TYPE_NUMBER) {
NPF_ERR_DEBUG(resp);
return EINVAL;
}
val = (int)nvlist_get_number(params, name);
if (set) {
/* Actually set the parameter. */
error = npfk_param_set(npf, name, val);
KASSERT(error == 0);
continue;
}
/* Validate the parameter and its value. */
error = npf_param_check(npf, name, val);
if (__predict_true(error == 0)) {
continue;
}
if (error == ENOENT) {
nvlist_add_stringf(resp, "error-msg",
"invalid parameter `%s`", name);
}
if (error == EINVAL) {
nvlist_add_stringf(resp, "error-msg",
"invalid parameter `%s` value %d", name, val);
}
return error;
}
return 0;
}
static int __noinline
npf_mk_table_entries(npf_table_t *t, const nvlist_t *req, nvlist_t *resp)
{
const nvlist_t * const *entries;
size_t nitems;
int error = 0;
if (!nvlist_exists_nvlist_array(req, "entries")) {
return 0;
}
entries = nvlist_get_nvlist_array(req, "entries", &nitems);
for (unsigned i = 0; i < nitems; i++) {
const nvlist_t *entry = entries[i];
const npf_addr_t *addr;
npf_netmask_t mask;
size_t alen;
/* Get address and mask; add a table entry. */
addr = dnvlist_get_binary(entry, "addr", &alen, NULL, 0);
mask = dnvlist_get_number(entry, "mask", NPF_NO_NETMASK);
if (addr == NULL || alen == 0) {
NPF_ERR_DEBUG(resp);
error = EINVAL;
break;
}
error = npf_table_insert(t, alen, addr, mask);
if (__predict_false(error)) {
if (error == EEXIST) {
nvlist_add_stringf(resp, "error-msg",
"table `%s' has a duplicate entry",
nvlist_get_string(req, "name"));
} else {
NPF_ERR_DEBUG(resp);
}
break;
}
}
return error;
}
/*
* npf_mk_table: create a table from provided nvlist.
*/
static int __noinline
npf_mk_table(npf_t *npf, const nvlist_t *req, nvlist_t *resp,
npf_tableset_t *tblset, npf_table_t **tblp, bool replacing)
{
npf_table_t *t;
const char *name;
const void *blob;
uint64_t tid;
size_t size;
int type;
int error = 0;
KASSERT(tblp != NULL);
/* Table name, ID and type. Validate them. */
name = dnvlist_get_string(req, "name", NULL);
if (!name) {
NPF_ERR_DEBUG(resp);
error = EINVAL;
goto out;
}
tid = dnvlist_get_number(req, "id", UINT64_MAX);
type = dnvlist_get_number(req, "type", UINT64_MAX);
error = npf_table_check(tblset, name, tid, type, replacing);
if (error) {
NPF_ERR_DEBUG(resp);
goto out;
}
/* Get the entries or binary data. */
blob = dnvlist_get_binary(req, "data", &size, NULL, 0);
if (type == NPF_TABLE_CONST && (blob == NULL || size == 0)) {
NPF_ERR_DEBUG(resp);
error = EINVAL;
goto out;
}
t = npf_table_create(name, (unsigned)tid, type, blob, size);
if (t == NULL) {
NPF_ERR_DEBUG(resp);
error = ENOMEM;
goto out;
}
if ((error = npf_mk_table_entries(t, req, resp)) != 0) {
npf_table_destroy(t);
goto out;
}
*tblp = t;
out:
return error;
}
static int __noinline
npf_mk_tables(npf_t *npf, const nvlist_t *req, nvlist_t *resp, npf_config_t *nc)
{
const nvlist_t * const *tables;
npf_tableset_t *tblset;
size_t nitems;
int error = 0;
if (nvlist_exists_nvlist_array(req, "tables")) {
tables = nvlist_get_nvlist_array(req, "tables", &nitems);
if (nitems > NPF_MAX_TABLES) {
NPF_ERR_DEBUG(resp);
return E2BIG;
}
} else {
tables = NULL;
nitems = 0;
}
tblset = npf_tableset_create(nitems);
for (unsigned i = 0; i < nitems; i++) {
const nvlist_t *table = tables[i];
npf_table_t *t;
error = npf_mk_table(npf, table, resp, tblset, &t, 0);
if (error) {
break;
}
error = npf_tableset_insert(tblset, t);
KASSERT(error == 0);
}
nc->tableset = tblset;
return error;
}
static npf_rproc_t *
npf_mk_singlerproc(npf_t *npf, const nvlist_t *rproc, nvlist_t *resp)
{
const nvlist_t * const *extcalls;
size_t nitems;
npf_rproc_t *rp;
if ((rp = npf_rproc_create(rproc)) == NULL) {
NPF_ERR_DEBUG(resp);
return NULL;
}
if (!nvlist_exists_nvlist_array(rproc, "extcalls")) {
return rp;
}
extcalls = nvlist_get_nvlist_array(rproc, "extcalls", &nitems);
for (unsigned i = 0; i < nitems; i++) {
const nvlist_t *extcall = extcalls[i];
const char *name;
name = dnvlist_get_string(extcall, "name", NULL);
if (!name || npf_ext_construct(npf, name, rp, extcall)) {
NPF_ERR_DEBUG(resp);
npf_rproc_release(rp);
rp = NULL;
break;
}
}
return rp;
}
static int __noinline
npf_mk_rprocs(npf_t *npf, const nvlist_t *req, nvlist_t *resp, npf_config_t *nc)
{
const nvlist_t * const *rprocs;
npf_rprocset_t *rpset;
size_t nitems;
int error = 0;
if (nvlist_exists_nvlist_array(req, "rprocs")) {
rprocs = nvlist_get_nvlist_array(req, "rprocs", &nitems);
if (nitems > NPF_MAX_RPROCS) {
NPF_ERR_DEBUG(resp);
return E2BIG;
}
} else {
rprocs = NULL;
nitems = 0;
}
rpset = npf_rprocset_create();
for (unsigned i = 0; i < nitems; i++) {
const nvlist_t *rproc = rprocs[i];
npf_rproc_t *rp;
if ((rp = npf_mk_singlerproc(npf, rproc, resp)) == NULL) {
error = EINVAL;
break;
}
npf_rprocset_insert(rpset, rp);
}
nc->rule_procs = rpset;
return error;
}
static int __noinline
npf_mk_algs(npf_t *npf, const nvlist_t *req, nvlist_t *resp)
{
const nvlist_t * const *algs;
size_t nitems;
if (nvlist_exists_nvlist_array(req, "algs")) {
algs = nvlist_get_nvlist_array(req, "algs", &nitems);
} else {
algs = NULL;
nitems = 0;
}
for (unsigned i = 0; i < nitems; i++) {
const nvlist_t *alg = algs[i];
const char *name;
name = dnvlist_get_string(alg, "name", NULL);
if (!name) {
NPF_ERR_DEBUG(resp);
return EINVAL;
}
if (!npf_alg_construct(npf, name)) {
NPF_ERR_DEBUG(resp);
return EINVAL;
}
}
return 0;
}
static int __noinline
npf_mk_singlerule(npf_t *npf, const nvlist_t *req, nvlist_t *resp,
npf_rprocset_t *rpset, npf_rule_t **rlret)
{
npf_rule_t *rl;
const char *rname;
const void *code;
size_t clen;
int error = 0;
if ((rl = npf_rule_alloc(npf, req)) == NULL) {
NPF_ERR_DEBUG(resp);
return EINVAL;
}
/* Assign the rule procedure, if any. */
if ((rname = dnvlist_get_string(req, "rproc", NULL)) != NULL) {
npf_rproc_t *rp;
if (rpset == NULL) {
NPF_ERR_DEBUG(resp);
error = EINVAL;
goto err;
}
if ((rp = npf_rprocset_lookup(rpset, rname)) == NULL) {
NPF_ERR_DEBUG(resp);
error = EINVAL;
goto err;
}
npf_rule_setrproc(rl, rp);
}
/* Filter byte-code (binary data). */
code = dnvlist_get_binary(req, "code", &clen, NULL, 0);
if (code) {
void *bc;
int type;
type = dnvlist_get_number(req, "code-type", UINT64_MAX);
if (type != NPF_CODE_BPF) {
NPF_ERR_DEBUG(resp);
error = ENOTSUP;
goto err;
}
if (clen == 0) {
NPF_ERR_DEBUG(resp);
error = EINVAL;
goto err;
}
if (!npf_bpf_validate(code, clen)) {
NPF_ERR_DEBUG(resp);
error = EINVAL;
goto err;
}
bc = kmem_alloc(clen, KM_SLEEP);
memcpy(bc, code, clen); // XXX: use nvlist_take
npf_rule_setcode(rl, type, bc, clen);
}
*rlret = rl;
return 0;
err:
nvlist_add_number(resp, "id", dnvlist_get_number(req, "prio", 0));
npf_rule_free(rl);
return error;
}
static int __noinline
npf_mk_rules(npf_t *npf, const nvlist_t *req, nvlist_t *resp, npf_config_t *nc)
{
const nvlist_t * const *rules;
npf_ruleset_t *rlset;
size_t nitems;
int error = 0;
if (nvlist_exists_nvlist_array(req, "rules")) {
rules = nvlist_get_nvlist_array(req, "rules", &nitems);
if (nitems > NPF_MAX_RULES) {
NPF_ERR_DEBUG(resp);
return E2BIG;
}
} else {
rules = NULL;
nitems = 0;
}
rlset = npf_ruleset_create(nitems);
for (unsigned i = 0; i < nitems; i++) {
const nvlist_t *rule = rules[i];
npf_rule_t *rl = NULL;
const char *name;
error = npf_mk_singlerule(npf, rule, resp, nc->rule_procs, &rl);
if (error) {
break;
}
name = dnvlist_get_string(rule, "name", NULL);
if (name && npf_ruleset_lookup(rlset, name)) {
NPF_ERR_DEBUG(resp);
npf_rule_free(rl);
error = EEXIST;
break;
}
npf_ruleset_insert(rlset, rl);
}
nc->ruleset = rlset;
return error;
}
static int __noinline
npf_mk_singlenat(npf_t *npf, const nvlist_t *nat, nvlist_t *resp,
npf_ruleset_t *ntset, npf_tableset_t *tblset, npf_rule_t **rlp)
{
npf_rule_t *rl = NULL;
npf_natpolicy_t *np;
int error;
/*
* NAT rules are standard rules, plus the translation policy.
* We first construct the rule structure.
*/
error = npf_mk_singlerule(npf, nat, resp, NULL, &rl);
if (error) {
return error;
}
KASSERT(rl != NULL);
*rlp = rl;
/* If this rule is named, then it is a group with NAT policies. */
if (dnvlist_get_string(nat, "name", NULL)) {
return 0;
}
/* Check the table ID. */
if (nvlist_exists_number(nat, "nat-table-id")) {
unsigned tid = nvlist_get_number(nat, "nat-table-id");
if (!npf_tableset_getbyid(tblset, tid)) {
NPF_ERR_DEBUG(resp);
error = EINVAL;
goto out;
}
}
/* Allocate a new NAT policy and assign it to the rule. */
np = npf_natpolicy_create(npf, nat, ntset);
if (np == NULL) {
NPF_ERR_DEBUG(resp);
error = ENOMEM;
goto out;
}
npf_rule_setnat(rl, np);
out:
if (error) {
npf_rule_free(rl);
}
return error;
}
static int __noinline
npf_mk_natlist(npf_t *npf, const nvlist_t *req, nvlist_t *resp, npf_config_t *nc)
{
const nvlist_t * const *nat_rules;
npf_ruleset_t *ntset;
size_t nitems;
int error = 0;
/*
* NAT policies must be an array, but enforce a limit.
*/
if (nvlist_exists_nvlist_array(req, "nat")) {
nat_rules = nvlist_get_nvlist_array(req, "nat", &nitems);
if (nitems > NPF_MAX_RULES) {
NPF_ERR_DEBUG(resp);
return E2BIG;
}
} else {
nat_rules = NULL;
nitems = 0;
}
ntset = npf_ruleset_create(nitems);
for (unsigned i = 0; i < nitems; i++) {
const nvlist_t *nat = nat_rules[i];
npf_rule_t *rl = NULL;
error = npf_mk_singlenat(npf, nat, resp, ntset,
nc->tableset, &rl);
if (error) {
break;
}
npf_ruleset_insert(ntset, rl);
}
nc->nat_ruleset = ntset;
return error;
}
/*
* npf_mk_connlist: import a list of connections and load them.
*/
static int __noinline
npf_mk_connlist(npf_t *npf, const nvlist_t *req, nvlist_t *resp,
npf_config_t *nc, npf_conndb_t **conndb)
{
const nvlist_t * const *conns;
npf_conndb_t *cd;
size_t nitems;
int error = 0;
if (!nvlist_exists_nvlist_array(req, "conn-list")) {
*conndb = NULL;
return 0;
}
cd = npf_conndb_create();
conns = nvlist_get_nvlist_array(req, "conn-list", &nitems);
for (unsigned i = 0; i < nitems; i++) {
const nvlist_t *conn = conns[i];
/* Construct and insert the connection. */
error = npf_conn_import(npf, cd, conn, nc->nat_ruleset);
if (error) {
NPF_ERR_DEBUG(resp);
break;
}
}
if (error) {
npf_conndb_gc(npf, cd, true, false);
npf_conndb_destroy(cd);
} else {
*conndb = cd;
}
return error;
}
/*
* npfctl_load: store passed data i.e. the update settings, create the
* passed rules, tables, etc and atomically activate them all.
*/
static int
npfctl_load(npf_t *npf, const nvlist_t *req, nvlist_t *resp)
{
npf_config_t *nc;
npf_conndb_t *conndb = NULL;
bool flush;
int error;
nc = npf_config_create();
error = npf_mk_params(npf, req, resp, false /* validate */);
if (error) {
goto fail;
}
error = npf_mk_algs(npf, req, resp);
if (error) {
goto fail;
}
error = npf_mk_tables(npf, req, resp, nc);
if (error) {
goto fail;
}
error = npf_mk_rprocs(npf, req, resp, nc);
if (error) {
goto fail;
}
error = npf_mk_natlist(npf, req, resp, nc);
if (error) {
goto fail;
}
error = npf_mk_rules(npf, req, resp, nc);
if (error) {
goto fail;
}
error = npf_mk_connlist(npf, req, resp, nc, &conndb);
if (error) {
goto fail;
}
flush = dnvlist_get_bool(req, "flush", false);
nc->default_pass = flush;
/*
* Finally - perform the load.
*/
npf_config_load(npf, nc, conndb, flush);
npf_mk_params(npf, req, resp, true /* set the params */);
return 0;
fail:
npf_config_destroy(nc);
return error;
}
/*
* npfctl_save: export the active configuration, including the current
* snapshot of the connections. Additionally, set the version and indicate
* whether the ruleset is currently active.
*/
static int
npfctl_save(npf_t *npf, const nvlist_t *req, nvlist_t *resp)
{
npf_config_t *nc;
int error;
/*
* Serialize the whole NPF configuration, including connections.
*/
nvlist_add_number(resp, "version", NPF_VERSION);
nc = npf_config_enter(npf);
error = npf_params_export(npf, resp);
if (error) {
goto out;
}
error = npf_conndb_export(npf, resp);
if (error) {
goto out;
}
error = npf_ruleset_export(npf, nc->ruleset, "rules", resp);
if (error) {
goto out;
}
error = npf_ruleset_export(npf, nc->nat_ruleset, "nat", resp);
if (error) {
goto out;
}
error = npf_tableset_export(npf, nc->tableset, resp);
if (error) {
goto out;
}
error = npf_rprocset_export(nc->rule_procs, resp);
if (error) {
goto out;
}
error = npf_alg_export(npf, resp);
if (error) {
goto out;
}
nvlist_add_bool(resp, "active", npf_active_p());
out:
npf_config_exit(npf);
return error;
}
/*
* npfctl_table_replace: atomically replace a table's contents with
* the passed table data.
*/
static int __noinline
npfctl_table_replace(npf_t *npf, const nvlist_t *req, nvlist_t *resp)
{
npf_table_t *tbl, *gc_tbl = NULL;
npf_config_t *nc;
int error = 0;
nc = npf_config_enter(npf);
error = npf_mk_table(npf, req, resp, nc->tableset, &tbl, true);
if (error) {
goto err;
}
gc_tbl = npf_tableset_swap(nc->tableset, tbl);
if (gc_tbl == NULL) {
error = EINVAL;
gc_tbl = tbl;
goto err;
}
npf_config_sync(npf);
err:
npf_config_exit(npf);
if (gc_tbl) {
npf_table_destroy(gc_tbl);
}
return error;
}
/*
* npfctl_rule: add or remove dynamic rules in the specified ruleset.
*/
static int
npfctl_rule(npf_t *npf, const nvlist_t *req, nvlist_t *resp)
{
npf_ruleset_t *rlset;
npf_rule_t *rl = NULL;
const char *ruleset_name;
npf_config_t *nc;
uint32_t rcmd;
int error = 0;
bool natset;
rcmd = dnvlist_get_number(req, "command", 0);
natset = dnvlist_get_bool(req, "nat-ruleset", false);
ruleset_name = dnvlist_get_string(req, "ruleset-name", NULL);
if (!ruleset_name) {
error = EINVAL;
goto out;
}
nc = npf_config_enter(npf);
rlset = natset ? nc->nat_ruleset : nc->ruleset;
switch (rcmd) {
case NPF_CMD_RULE_ADD: {
if (natset) {
/*
* Translation rule.
*/
error = npf_mk_singlenat(npf, req, resp, rlset,
nc->tableset, &rl);
} else {
/*
* Standard rule.
*/
error = npf_mk_singlerule(npf, req, resp, NULL, &rl);
}
if (error) {
goto out;
}
if ((error = npf_ruleset_add(rlset, ruleset_name, rl)) == 0) {
/* Success. */
uint64_t id = npf_rule_getid(rl);
nvlist_add_number(resp, "id", id);
rl = NULL;
}
break;
}
case NPF_CMD_RULE_REMOVE: {
uint64_t id = dnvlist_get_number(req, "id", UINT64_MAX);
error = npf_ruleset_remove(rlset, ruleset_name, id);
break;
}
case NPF_CMD_RULE_REMKEY: {
const void *key;
size_t len;
key = dnvlist_get_binary(req, "key", &len, NULL, 0);
if (len == 0 || len > NPF_RULE_MAXKEYLEN) {
error = EINVAL;
break;
}
error = npf_ruleset_remkey(rlset, ruleset_name, key, len);
break;
}
case NPF_CMD_RULE_LIST: {
error = npf_ruleset_list(npf, rlset, ruleset_name, resp);
break;
}
case NPF_CMD_RULE_FLUSH: {
error = npf_ruleset_flush(rlset, ruleset_name);
break;
}
default:
error = EINVAL;
break;
}
/* Destroy any removed rules. */
if (!error && rcmd != NPF_CMD_RULE_ADD && rcmd != NPF_CMD_RULE_LIST) {
npf_config_sync(npf);
npf_ruleset_gc(rlset);
}
out:
npf_config_exit(npf);
if (rl) {
KASSERT(error);
npf_rule_free(rl);
}
return error;
}
/*
* npfctl_table: add, remove or query entries in the specified table.
*
* For maximum performance, the interface is using plain structures.
*/
int
npfctl_table(npf_t *npf, void *data)
{
const npf_ioctl_table_t *nct = data;
char tname[NPF_TABLE_MAXNAMELEN];
npf_config_t *nc;
npf_table_t *t;
int error;
error = copyinstr(nct->nct_name, tname, sizeof(tname), NULL);
if (error) {
return error;
}
nc = npf_config_enter(npf);
if ((t = npf_tableset_getbyname(nc->tableset, tname)) == NULL) {
npf_config_exit(npf);
return EINVAL;
}
switch (nct->nct_cmd) {
case NPF_CMD_TABLE_LOOKUP:
error = npf_table_lookup(t, nct->nct_data.ent.alen,
&nct->nct_data.ent.addr);
break;
case NPF_CMD_TABLE_ADD:
error = npf_table_insert(t, nct->nct_data.ent.alen,
&nct->nct_data.ent.addr, nct->nct_data.ent.mask);
break;
case NPF_CMD_TABLE_REMOVE:
error = npf_table_remove(t, nct->nct_data.ent.alen,
&nct->nct_data.ent.addr, nct->nct_data.ent.mask);
break;
case NPF_CMD_TABLE_LIST:
error = npf_table_list(t, nct->nct_data.buf.buf,
nct->nct_data.buf.len);
break;
case NPF_CMD_TABLE_FLUSH:
error = npf_table_flush(t);
break;
default:
error = EINVAL;
break;
}
npf_table_gc(npf, t);
npf_config_exit(npf);
return error;
}
/*
* npfctl_run_op: run a particular NPF operation with a given the request.
*
* => Checks the ABI version.
* => Sets the error number for the response.
*/
int
npfctl_run_op(npf_t *npf, unsigned op, const nvlist_t *req, nvlist_t *resp)
{
uint64_t ver;
int error;
ver = dnvlist_get_number(req, "version", UINT64_MAX);
if (__predict_false(ver != UINT64_MAX && ver != NPF_VERSION)) {
return EPROGMISMATCH;
}
switch (op) {
case IOC_NPF_LOAD:
error = npfctl_load(npf, req, resp);
break;
case IOC_NPF_SAVE:
error = npfctl_save(npf, req, resp);
break;
case IOC_NPF_RULE:
error = npfctl_rule(npf, req, resp);
break;
case IOC_NPF_CONN_LOOKUP:
error = npf_conn_find(npf, req, resp);
break;
case IOC_NPF_TABLE_REPLACE:
error = npfctl_table_replace(npf, req, resp);
break;
default:
error = ENOTTY;
break;
}
nvlist_add_number(resp, "errno", error);
return error;
}