linux_dsm_epyc7002/net/rxrpc/security.c
David Howells 28036f4485 rxrpc: Permit multiple service binding
Permit bind() to be called on an AF_RXRPC socket more than once (currently
maximum twice) to bind multiple listening services to it.  There are some
restrictions:

 (1) All bind() calls involved must have a non-zero service ID.

 (2) The service IDs must all be different.

 (3) The rest of the address (notably the transport part) must be the same
     in all (a single UDP socket is shared).

 (4) This must be done before listen() or sendmsg() is called.

This allows someone to connect to the service socket with different service
IDs and lays the foundation for service upgrading.

The service ID used by an incoming call can be extracted from the msg_name
returned by recvmsg().

Signed-off-by: David Howells <dhowells@redhat.com>
2017-06-05 14:30:49 +01:00

170 lines
3.7 KiB
C

/* RxRPC security handling
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/udp.h>
#include <linux/crypto.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <keys/rxrpc-type.h>
#include "ar-internal.h"
static LIST_HEAD(rxrpc_security_methods);
static DECLARE_RWSEM(rxrpc_security_sem);
static const struct rxrpc_security *rxrpc_security_types[] = {
[RXRPC_SECURITY_NONE] = &rxrpc_no_security,
#ifdef CONFIG_RXKAD
[RXRPC_SECURITY_RXKAD] = &rxkad,
#endif
};
int __init rxrpc_init_security(void)
{
int i, ret;
for (i = 0; i < ARRAY_SIZE(rxrpc_security_types); i++) {
if (rxrpc_security_types[i]) {
ret = rxrpc_security_types[i]->init();
if (ret < 0)
goto failed;
}
}
return 0;
failed:
for (i--; i >= 0; i--)
if (rxrpc_security_types[i])
rxrpc_security_types[i]->exit();
return ret;
}
void rxrpc_exit_security(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(rxrpc_security_types); i++)
if (rxrpc_security_types[i])
rxrpc_security_types[i]->exit();
}
/*
* look up an rxrpc security module
*/
static const struct rxrpc_security *rxrpc_security_lookup(u8 security_index)
{
if (security_index >= ARRAY_SIZE(rxrpc_security_types))
return NULL;
return rxrpc_security_types[security_index];
}
/*
* initialise the security on a client connection
*/
int rxrpc_init_client_conn_security(struct rxrpc_connection *conn)
{
const struct rxrpc_security *sec;
struct rxrpc_key_token *token;
struct key *key = conn->params.key;
int ret;
_enter("{%d},{%x}", conn->debug_id, key_serial(key));
if (!key)
return 0;
ret = key_validate(key);
if (ret < 0)
return ret;
token = key->payload.data[0];
if (!token)
return -EKEYREJECTED;
sec = rxrpc_security_lookup(token->security_index);
if (!sec)
return -EKEYREJECTED;
conn->security = sec;
ret = conn->security->init_connection_security(conn);
if (ret < 0) {
conn->security = &rxrpc_no_security;
return ret;
}
_leave(" = 0");
return 0;
}
/*
* initialise the security on a server connection
*/
int rxrpc_init_server_conn_security(struct rxrpc_connection *conn)
{
const struct rxrpc_security *sec;
struct rxrpc_local *local = conn->params.local;
struct rxrpc_sock *rx;
struct key *key;
key_ref_t kref;
char kdesc[5 + 1 + 3 + 1];
_enter("");
sprintf(kdesc, "%u:%u", conn->service_id, conn->security_ix);
sec = rxrpc_security_lookup(conn->security_ix);
if (!sec) {
_leave(" = -ENOKEY [lookup]");
return -ENOKEY;
}
/* find the service */
read_lock(&local->services_lock);
rx = rcu_dereference_protected(local->service,
lockdep_is_held(&local->services_lock));
if (rx && (rx->srx.srx_service == conn->service_id ||
rx->second_service == conn->service_id))
goto found_service;
/* the service appears to have died */
read_unlock(&local->services_lock);
_leave(" = -ENOENT");
return -ENOENT;
found_service:
if (!rx->securities) {
read_unlock(&local->services_lock);
_leave(" = -ENOKEY");
return -ENOKEY;
}
/* look through the service's keyring */
kref = keyring_search(make_key_ref(rx->securities, 1UL),
&key_type_rxrpc_s, kdesc);
if (IS_ERR(kref)) {
read_unlock(&local->services_lock);
_leave(" = %ld [search]", PTR_ERR(kref));
return PTR_ERR(kref);
}
key = key_ref_to_ptr(kref);
read_unlock(&local->services_lock);
conn->server_key = key;
conn->security = sec;
_leave(" = 0");
return 0;
}