linux/net/rxrpc/security.c
David Howells 12da59fcab rxrpc: Hand server key parsing off to the security class
Hand responsibility for parsing a server key off to the security class.  We
can determine which class from the description.  This is necessary as rxgk
server keys have different lookup requirements and different content
requirements (dependent on crypto type) to those of rxkad server keys.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-11-23 18:09:29 +00:00

191 lines
4.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* RxRPC security handling
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#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 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
*/
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;
for (token = key->payload.data[0]; token; token = token->next) {
sec = rxrpc_security_lookup(token->security_index);
if (sec)
goto found;
}
return -EKEYREJECTED;
found:
conn->security = sec;
ret = conn->security->init_connection_security(conn, token);
if (ret < 0) {
conn->security = &rxrpc_no_security;
return ret;
}
_leave(" = 0");
return 0;
}
/*
* Set the ops a server connection.
*/
const struct rxrpc_security *rxrpc_get_incoming_security(struct rxrpc_sock *rx,
struct sk_buff *skb)
{
const struct rxrpc_security *sec;
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
_enter("");
sec = rxrpc_security_lookup(sp->hdr.securityIndex);
if (!sec) {
trace_rxrpc_abort(0, "SVS",
sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
RX_INVALID_OPERATION, EKEYREJECTED);
skb->mark = RXRPC_SKB_MARK_REJECT_ABORT;
skb->priority = RX_INVALID_OPERATION;
return NULL;
}
if (sp->hdr.securityIndex != RXRPC_SECURITY_NONE &&
!rx->securities) {
trace_rxrpc_abort(0, "SVR",
sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
RX_INVALID_OPERATION, EKEYREJECTED);
skb->mark = RXRPC_SKB_MARK_REJECT_ABORT;
skb->priority = sec->no_key_abort;
return NULL;
}
return sec;
}
/*
* Find the security key for a server connection.
*/
struct key *rxrpc_look_up_server_security(struct rxrpc_connection *conn,
struct sk_buff *skb,
u32 kvno, u32 enctype)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
struct rxrpc_sock *rx;
struct key *key = ERR_PTR(-EKEYREJECTED);
key_ref_t kref = NULL;
char kdesc[5 + 1 + 3 + 1 + 12 + 1 + 12 + 1];
int ret;
_enter("");
if (enctype)
sprintf(kdesc, "%u:%u:%u:%u",
sp->hdr.serviceId, sp->hdr.securityIndex, kvno, enctype);
else if (kvno)
sprintf(kdesc, "%u:%u:%u",
sp->hdr.serviceId, sp->hdr.securityIndex, kvno);
else
sprintf(kdesc, "%u:%u",
sp->hdr.serviceId, sp->hdr.securityIndex);
rcu_read_lock();
rx = rcu_dereference(conn->params.local->service);
if (!rx)
goto out;
/* look through the service's keyring */
kref = keyring_search(make_key_ref(rx->securities, 1UL),
&key_type_rxrpc_s, kdesc, true);
if (IS_ERR(kref)) {
key = ERR_CAST(kref);
goto out;
}
key = key_ref_to_ptr(kref);
ret = key_validate(key);
if (ret < 0) {
key_put(key);
key = ERR_PTR(ret);
goto out;
}
out:
rcu_read_unlock();
return key;
}