![David Howells](/assets/img/avatar_default.png)
Ask the security class how much header and trailer space to allow for when allocating a packet, given how much data is remaining. This will allow the rxgk security class to stick both a trailer in as well as a header as appropriate in the future. Signed-off-by: David Howells <dhowells@redhat.com>
1408 lines
35 KiB
C
1408 lines
35 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/* Kerberos-based RxRPC security
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*
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* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <crypto/skcipher.h>
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#include <linux/module.h>
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#include <linux/net.h>
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#include <linux/skbuff.h>
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#include <linux/udp.h>
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#include <linux/scatterlist.h>
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#include <linux/ctype.h>
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#include <linux/slab.h>
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#include <linux/key-type.h>
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#include <net/sock.h>
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#include <net/af_rxrpc.h>
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#include <keys/rxrpc-type.h>
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#include "ar-internal.h"
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#define RXKAD_VERSION 2
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#define MAXKRB5TICKETLEN 1024
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#define RXKAD_TKT_TYPE_KERBEROS_V5 256
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#define ANAME_SZ 40 /* size of authentication name */
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#define INST_SZ 40 /* size of principal's instance */
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#define REALM_SZ 40 /* size of principal's auth domain */
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#define SNAME_SZ 40 /* size of service name */
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#define RXKAD_ALIGN 8
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struct rxkad_level1_hdr {
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__be32 data_size; /* true data size (excluding padding) */
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};
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struct rxkad_level2_hdr {
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__be32 data_size; /* true data size (excluding padding) */
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__be32 checksum; /* decrypted data checksum */
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};
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static int rxkad_prime_packet_security(struct rxrpc_connection *conn,
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struct crypto_sync_skcipher *ci);
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/*
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* this holds a pinned cipher so that keventd doesn't get called by the cipher
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* alloc routine, but since we have it to hand, we use it to decrypt RESPONSE
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* packets
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*/
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static struct crypto_sync_skcipher *rxkad_ci;
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static struct skcipher_request *rxkad_ci_req;
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static DEFINE_MUTEX(rxkad_ci_mutex);
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/*
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* Parse the information from a server key
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*
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* The data should be the 8-byte secret key.
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*/
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static int rxkad_preparse_server_key(struct key_preparsed_payload *prep)
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{
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struct crypto_skcipher *ci;
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if (prep->datalen != 8)
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return -EINVAL;
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memcpy(&prep->payload.data[2], prep->data, 8);
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ci = crypto_alloc_skcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
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if (IS_ERR(ci)) {
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_leave(" = %ld", PTR_ERR(ci));
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return PTR_ERR(ci);
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}
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if (crypto_skcipher_setkey(ci, prep->data, 8) < 0)
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BUG();
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prep->payload.data[0] = ci;
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_leave(" = 0");
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return 0;
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}
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static void rxkad_free_preparse_server_key(struct key_preparsed_payload *prep)
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{
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if (prep->payload.data[0])
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crypto_free_skcipher(prep->payload.data[0]);
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}
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static void rxkad_destroy_server_key(struct key *key)
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{
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if (key->payload.data[0]) {
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crypto_free_skcipher(key->payload.data[0]);
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key->payload.data[0] = NULL;
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}
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}
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/*
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* initialise connection security
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*/
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static int rxkad_init_connection_security(struct rxrpc_connection *conn,
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struct rxrpc_key_token *token)
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{
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struct crypto_sync_skcipher *ci;
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int ret;
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_enter("{%d},{%x}", conn->debug_id, key_serial(conn->params.key));
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conn->security_ix = token->security_index;
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ci = crypto_alloc_sync_skcipher("pcbc(fcrypt)", 0, 0);
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if (IS_ERR(ci)) {
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_debug("no cipher");
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ret = PTR_ERR(ci);
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goto error;
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}
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if (crypto_sync_skcipher_setkey(ci, token->kad->session_key,
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sizeof(token->kad->session_key)) < 0)
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BUG();
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switch (conn->params.security_level) {
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case RXRPC_SECURITY_PLAIN:
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case RXRPC_SECURITY_AUTH:
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case RXRPC_SECURITY_ENCRYPT:
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break;
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default:
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ret = -EKEYREJECTED;
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goto error;
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}
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ret = rxkad_prime_packet_security(conn, ci);
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if (ret < 0)
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goto error_ci;
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conn->rxkad.cipher = ci;
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return 0;
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error_ci:
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crypto_free_sync_skcipher(ci);
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error:
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_leave(" = %d", ret);
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return ret;
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}
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/*
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* Work out how much data we can put in a packet.
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*/
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static int rxkad_how_much_data(struct rxrpc_call *call, size_t remain,
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size_t *_buf_size, size_t *_data_size, size_t *_offset)
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{
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size_t shdr, buf_size, chunk;
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switch (call->conn->params.security_level) {
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default:
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buf_size = chunk = min_t(size_t, remain, RXRPC_JUMBO_DATALEN);
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shdr = 0;
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goto out;
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case RXRPC_SECURITY_AUTH:
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shdr = sizeof(struct rxkad_level1_hdr);
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break;
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case RXRPC_SECURITY_ENCRYPT:
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shdr = sizeof(struct rxkad_level2_hdr);
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break;
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}
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buf_size = round_down(RXRPC_JUMBO_DATALEN, RXKAD_ALIGN);
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chunk = buf_size - shdr;
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if (remain < chunk)
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buf_size = round_up(shdr + remain, RXKAD_ALIGN);
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out:
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*_buf_size = buf_size;
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*_data_size = chunk;
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*_offset = shdr;
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return 0;
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}
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/*
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* prime the encryption state with the invariant parts of a connection's
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* description
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*/
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static int rxkad_prime_packet_security(struct rxrpc_connection *conn,
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struct crypto_sync_skcipher *ci)
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{
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struct skcipher_request *req;
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struct rxrpc_key_token *token;
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struct scatterlist sg;
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struct rxrpc_crypt iv;
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__be32 *tmpbuf;
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size_t tmpsize = 4 * sizeof(__be32);
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_enter("");
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if (!conn->params.key)
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return 0;
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tmpbuf = kmalloc(tmpsize, GFP_KERNEL);
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if (!tmpbuf)
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return -ENOMEM;
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req = skcipher_request_alloc(&ci->base, GFP_NOFS);
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if (!req) {
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kfree(tmpbuf);
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return -ENOMEM;
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}
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token = conn->params.key->payload.data[0];
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memcpy(&iv, token->kad->session_key, sizeof(iv));
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tmpbuf[0] = htonl(conn->proto.epoch);
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tmpbuf[1] = htonl(conn->proto.cid);
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tmpbuf[2] = 0;
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tmpbuf[3] = htonl(conn->security_ix);
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sg_init_one(&sg, tmpbuf, tmpsize);
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skcipher_request_set_sync_tfm(req, ci);
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skcipher_request_set_callback(req, 0, NULL, NULL);
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skcipher_request_set_crypt(req, &sg, &sg, tmpsize, iv.x);
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crypto_skcipher_encrypt(req);
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skcipher_request_free(req);
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memcpy(&conn->rxkad.csum_iv, tmpbuf + 2, sizeof(conn->rxkad.csum_iv));
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kfree(tmpbuf);
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_leave(" = 0");
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return 0;
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}
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/*
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* Allocate and prepare the crypto request on a call. For any particular call,
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* this is called serially for the packets, so no lock should be necessary.
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*/
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static struct skcipher_request *rxkad_get_call_crypto(struct rxrpc_call *call)
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{
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struct crypto_skcipher *tfm = &call->conn->rxkad.cipher->base;
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struct skcipher_request *cipher_req = call->cipher_req;
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if (!cipher_req) {
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cipher_req = skcipher_request_alloc(tfm, GFP_NOFS);
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if (!cipher_req)
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return NULL;
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call->cipher_req = cipher_req;
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}
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return cipher_req;
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}
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/*
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* Clean up the crypto on a call.
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*/
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static void rxkad_free_call_crypto(struct rxrpc_call *call)
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{
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if (call->cipher_req)
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skcipher_request_free(call->cipher_req);
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call->cipher_req = NULL;
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}
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/*
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* partially encrypt a packet (level 1 security)
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*/
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static int rxkad_secure_packet_auth(const struct rxrpc_call *call,
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struct sk_buff *skb, u32 data_size,
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struct skcipher_request *req)
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{
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struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
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struct rxkad_level1_hdr hdr;
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struct rxrpc_crypt iv;
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struct scatterlist sg;
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size_t pad;
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u16 check;
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_enter("");
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check = sp->hdr.seq ^ call->call_id;
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data_size |= (u32)check << 16;
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hdr.data_size = htonl(data_size);
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memcpy(skb->head, &hdr, sizeof(hdr));
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pad = sizeof(struct rxkad_level1_hdr) + data_size;
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pad = RXKAD_ALIGN - pad;
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pad &= RXKAD_ALIGN - 1;
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if (pad)
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skb_put_zero(skb, pad);
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/* start the encryption afresh */
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memset(&iv, 0, sizeof(iv));
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sg_init_one(&sg, skb->head, 8);
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skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
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skcipher_request_set_callback(req, 0, NULL, NULL);
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skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);
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crypto_skcipher_encrypt(req);
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skcipher_request_zero(req);
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_leave(" = 0");
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return 0;
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}
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/*
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* wholly encrypt a packet (level 2 security)
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*/
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static int rxkad_secure_packet_encrypt(const struct rxrpc_call *call,
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struct sk_buff *skb,
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u32 data_size,
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struct skcipher_request *req)
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{
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const struct rxrpc_key_token *token;
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struct rxkad_level2_hdr rxkhdr;
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struct rxrpc_skb_priv *sp;
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struct rxrpc_crypt iv;
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struct scatterlist sg[16];
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unsigned int len;
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size_t pad;
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u16 check;
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int err;
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sp = rxrpc_skb(skb);
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_enter("");
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check = sp->hdr.seq ^ call->call_id;
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rxkhdr.data_size = htonl(data_size | (u32)check << 16);
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rxkhdr.checksum = 0;
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memcpy(skb->head, &rxkhdr, sizeof(rxkhdr));
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pad = sizeof(struct rxkad_level2_hdr) + data_size;
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pad = RXKAD_ALIGN - pad;
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pad &= RXKAD_ALIGN - 1;
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if (pad)
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skb_put_zero(skb, pad);
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/* encrypt from the session key */
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token = call->conn->params.key->payload.data[0];
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memcpy(&iv, token->kad->session_key, sizeof(iv));
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sg_init_one(&sg[0], skb->head, sizeof(rxkhdr));
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skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
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skcipher_request_set_callback(req, 0, NULL, NULL);
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skcipher_request_set_crypt(req, &sg[0], &sg[0], sizeof(rxkhdr), iv.x);
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crypto_skcipher_encrypt(req);
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/* we want to encrypt the skbuff in-place */
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err = -EMSGSIZE;
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if (skb_shinfo(skb)->nr_frags > 16)
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goto out;
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len = round_up(data_size, RXKAD_ALIGN);
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sg_init_table(sg, ARRAY_SIZE(sg));
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err = skb_to_sgvec(skb, sg, 8, len);
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if (unlikely(err < 0))
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goto out;
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skcipher_request_set_crypt(req, sg, sg, len, iv.x);
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crypto_skcipher_encrypt(req);
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_leave(" = 0");
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err = 0;
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out:
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skcipher_request_zero(req);
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return err;
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}
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/*
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* checksum an RxRPC packet header
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*/
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static int rxkad_secure_packet(struct rxrpc_call *call,
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struct sk_buff *skb,
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size_t data_size)
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{
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struct rxrpc_skb_priv *sp;
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struct skcipher_request *req;
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struct rxrpc_crypt iv;
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struct scatterlist sg;
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u32 x, y;
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int ret;
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sp = rxrpc_skb(skb);
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_enter("{%d{%x}},{#%u},%zu,",
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call->debug_id, key_serial(call->conn->params.key),
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sp->hdr.seq, data_size);
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if (!call->conn->rxkad.cipher)
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return 0;
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ret = key_validate(call->conn->params.key);
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if (ret < 0)
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return ret;
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req = rxkad_get_call_crypto(call);
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if (!req)
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return -ENOMEM;
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/* continue encrypting from where we left off */
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memcpy(&iv, call->conn->rxkad.csum_iv.x, sizeof(iv));
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/* calculate the security checksum */
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x = (call->cid & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT);
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x |= sp->hdr.seq & 0x3fffffff;
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call->crypto_buf[0] = htonl(call->call_id);
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call->crypto_buf[1] = htonl(x);
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sg_init_one(&sg, call->crypto_buf, 8);
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skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
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skcipher_request_set_callback(req, 0, NULL, NULL);
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skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);
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crypto_skcipher_encrypt(req);
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skcipher_request_zero(req);
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y = ntohl(call->crypto_buf[1]);
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y = (y >> 16) & 0xffff;
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if (y == 0)
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y = 1; /* zero checksums are not permitted */
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sp->hdr.cksum = y;
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switch (call->conn->params.security_level) {
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case RXRPC_SECURITY_PLAIN:
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ret = 0;
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break;
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case RXRPC_SECURITY_AUTH:
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ret = rxkad_secure_packet_auth(call, skb, data_size, req);
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break;
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case RXRPC_SECURITY_ENCRYPT:
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ret = rxkad_secure_packet_encrypt(call, skb, data_size, req);
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break;
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default:
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ret = -EPERM;
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break;
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}
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_leave(" = %d [set %hx]", ret, y);
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return ret;
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}
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|
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/*
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* decrypt partial encryption on a packet (level 1 security)
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*/
|
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static int rxkad_verify_packet_1(struct rxrpc_call *call, struct sk_buff *skb,
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unsigned int offset, unsigned int len,
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rxrpc_seq_t seq,
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struct skcipher_request *req)
|
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{
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struct rxkad_level1_hdr sechdr;
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struct rxrpc_crypt iv;
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struct scatterlist sg[16];
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bool aborted;
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u32 data_size, buf;
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u16 check;
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int ret;
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_enter("");
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|
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if (len < 8) {
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aborted = rxrpc_abort_eproto(call, skb, "rxkad_1_hdr", "V1H",
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RXKADSEALEDINCON);
|
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goto protocol_error;
|
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}
|
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|
|
/* Decrypt the skbuff in-place. TODO: We really want to decrypt
|
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* directly into the target buffer.
|
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*/
|
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sg_init_table(sg, ARRAY_SIZE(sg));
|
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ret = skb_to_sgvec(skb, sg, offset, 8);
|
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if (unlikely(ret < 0))
|
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return ret;
|
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|
|
/* start the decryption afresh */
|
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memset(&iv, 0, sizeof(iv));
|
|
|
|
skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
|
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skcipher_request_set_callback(req, 0, NULL, NULL);
|
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skcipher_request_set_crypt(req, sg, sg, 8, iv.x);
|
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crypto_skcipher_decrypt(req);
|
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skcipher_request_zero(req);
|
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|
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/* Extract the decrypted packet length */
|
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if (skb_copy_bits(skb, offset, &sechdr, sizeof(sechdr)) < 0) {
|
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aborted = rxrpc_abort_eproto(call, skb, "rxkad_1_len", "XV1",
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RXKADDATALEN);
|
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goto protocol_error;
|
|
}
|
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offset += sizeof(sechdr);
|
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len -= sizeof(sechdr);
|
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|
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buf = ntohl(sechdr.data_size);
|
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data_size = buf & 0xffff;
|
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|
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check = buf >> 16;
|
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check ^= seq ^ call->call_id;
|
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check &= 0xffff;
|
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if (check != 0) {
|
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aborted = rxrpc_abort_eproto(call, skb, "rxkad_1_check", "V1C",
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RXKADSEALEDINCON);
|
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goto protocol_error;
|
|
}
|
|
|
|
if (data_size > len) {
|
|
aborted = rxrpc_abort_eproto(call, skb, "rxkad_1_datalen", "V1L",
|
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RXKADDATALEN);
|
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goto protocol_error;
|
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}
|
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|
|
_leave(" = 0 [dlen=%x]", data_size);
|
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return 0;
|
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|
|
protocol_error:
|
|
if (aborted)
|
|
rxrpc_send_abort_packet(call);
|
|
return -EPROTO;
|
|
}
|
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|
|
/*
|
|
* wholly decrypt a packet (level 2 security)
|
|
*/
|
|
static int rxkad_verify_packet_2(struct rxrpc_call *call, struct sk_buff *skb,
|
|
unsigned int offset, unsigned int len,
|
|
rxrpc_seq_t seq,
|
|
struct skcipher_request *req)
|
|
{
|
|
const struct rxrpc_key_token *token;
|
|
struct rxkad_level2_hdr sechdr;
|
|
struct rxrpc_crypt iv;
|
|
struct scatterlist _sg[4], *sg;
|
|
bool aborted;
|
|
u32 data_size, buf;
|
|
u16 check;
|
|
int nsg, ret;
|
|
|
|
_enter(",{%d}", skb->len);
|
|
|
|
if (len < 8) {
|
|
aborted = rxrpc_abort_eproto(call, skb, "rxkad_2_hdr", "V2H",
|
|
RXKADSEALEDINCON);
|
|
goto protocol_error;
|
|
}
|
|
|
|
/* Decrypt the skbuff in-place. TODO: We really want to decrypt
|
|
* directly into the target buffer.
|
|
*/
|
|
sg = _sg;
|
|
nsg = skb_shinfo(skb)->nr_frags;
|
|
if (nsg <= 4) {
|
|
nsg = 4;
|
|
} else {
|
|
sg = kmalloc_array(nsg, sizeof(*sg), GFP_NOIO);
|
|
if (!sg)
|
|
goto nomem;
|
|
}
|
|
|
|
sg_init_table(sg, nsg);
|
|
ret = skb_to_sgvec(skb, sg, offset, len);
|
|
if (unlikely(ret < 0)) {
|
|
if (sg != _sg)
|
|
kfree(sg);
|
|
return ret;
|
|
}
|
|
|
|
/* decrypt from the session key */
|
|
token = call->conn->params.key->payload.data[0];
|
|
memcpy(&iv, token->kad->session_key, sizeof(iv));
|
|
|
|
skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
|
|
skcipher_request_set_callback(req, 0, NULL, NULL);
|
|
skcipher_request_set_crypt(req, sg, sg, len, iv.x);
|
|
crypto_skcipher_decrypt(req);
|
|
skcipher_request_zero(req);
|
|
if (sg != _sg)
|
|
kfree(sg);
|
|
|
|
/* Extract the decrypted packet length */
|
|
if (skb_copy_bits(skb, offset, &sechdr, sizeof(sechdr)) < 0) {
|
|
aborted = rxrpc_abort_eproto(call, skb, "rxkad_2_len", "XV2",
|
|
RXKADDATALEN);
|
|
goto protocol_error;
|
|
}
|
|
offset += sizeof(sechdr);
|
|
len -= sizeof(sechdr);
|
|
|
|
buf = ntohl(sechdr.data_size);
|
|
data_size = buf & 0xffff;
|
|
|
|
check = buf >> 16;
|
|
check ^= seq ^ call->call_id;
|
|
check &= 0xffff;
|
|
if (check != 0) {
|
|
aborted = rxrpc_abort_eproto(call, skb, "rxkad_2_check", "V2C",
|
|
RXKADSEALEDINCON);
|
|
goto protocol_error;
|
|
}
|
|
|
|
if (data_size > len) {
|
|
aborted = rxrpc_abort_eproto(call, skb, "rxkad_2_datalen", "V2L",
|
|
RXKADDATALEN);
|
|
goto protocol_error;
|
|
}
|
|
|
|
_leave(" = 0 [dlen=%x]", data_size);
|
|
return 0;
|
|
|
|
protocol_error:
|
|
if (aborted)
|
|
rxrpc_send_abort_packet(call);
|
|
return -EPROTO;
|
|
|
|
nomem:
|
|
_leave(" = -ENOMEM");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* Verify the security on a received packet or subpacket (if part of a
|
|
* jumbo packet).
|
|
*/
|
|
static int rxkad_verify_packet(struct rxrpc_call *call, struct sk_buff *skb,
|
|
unsigned int offset, unsigned int len,
|
|
rxrpc_seq_t seq, u16 expected_cksum)
|
|
{
|
|
struct skcipher_request *req;
|
|
struct rxrpc_crypt iv;
|
|
struct scatterlist sg;
|
|
bool aborted;
|
|
u16 cksum;
|
|
u32 x, y;
|
|
|
|
_enter("{%d{%x}},{#%u}",
|
|
call->debug_id, key_serial(call->conn->params.key), seq);
|
|
|
|
if (!call->conn->rxkad.cipher)
|
|
return 0;
|
|
|
|
req = rxkad_get_call_crypto(call);
|
|
if (!req)
|
|
return -ENOMEM;
|
|
|
|
/* continue encrypting from where we left off */
|
|
memcpy(&iv, call->conn->rxkad.csum_iv.x, sizeof(iv));
|
|
|
|
/* validate the security checksum */
|
|
x = (call->cid & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT);
|
|
x |= seq & 0x3fffffff;
|
|
call->crypto_buf[0] = htonl(call->call_id);
|
|
call->crypto_buf[1] = htonl(x);
|
|
|
|
sg_init_one(&sg, call->crypto_buf, 8);
|
|
skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
|
|
skcipher_request_set_callback(req, 0, NULL, NULL);
|
|
skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);
|
|
crypto_skcipher_encrypt(req);
|
|
skcipher_request_zero(req);
|
|
|
|
y = ntohl(call->crypto_buf[1]);
|
|
cksum = (y >> 16) & 0xffff;
|
|
if (cksum == 0)
|
|
cksum = 1; /* zero checksums are not permitted */
|
|
|
|
if (cksum != expected_cksum) {
|
|
aborted = rxrpc_abort_eproto(call, skb, "rxkad_csum", "VCK",
|
|
RXKADSEALEDINCON);
|
|
goto protocol_error;
|
|
}
|
|
|
|
switch (call->conn->params.security_level) {
|
|
case RXRPC_SECURITY_PLAIN:
|
|
return 0;
|
|
case RXRPC_SECURITY_AUTH:
|
|
return rxkad_verify_packet_1(call, skb, offset, len, seq, req);
|
|
case RXRPC_SECURITY_ENCRYPT:
|
|
return rxkad_verify_packet_2(call, skb, offset, len, seq, req);
|
|
default:
|
|
return -ENOANO;
|
|
}
|
|
|
|
protocol_error:
|
|
if (aborted)
|
|
rxrpc_send_abort_packet(call);
|
|
return -EPROTO;
|
|
}
|
|
|
|
/*
|
|
* Locate the data contained in a packet that was partially encrypted.
|
|
*/
|
|
static void rxkad_locate_data_1(struct rxrpc_call *call, struct sk_buff *skb,
|
|
unsigned int *_offset, unsigned int *_len)
|
|
{
|
|
struct rxkad_level1_hdr sechdr;
|
|
|
|
if (skb_copy_bits(skb, *_offset, &sechdr, sizeof(sechdr)) < 0)
|
|
BUG();
|
|
*_offset += sizeof(sechdr);
|
|
*_len = ntohl(sechdr.data_size) & 0xffff;
|
|
}
|
|
|
|
/*
|
|
* Locate the data contained in a packet that was completely encrypted.
|
|
*/
|
|
static void rxkad_locate_data_2(struct rxrpc_call *call, struct sk_buff *skb,
|
|
unsigned int *_offset, unsigned int *_len)
|
|
{
|
|
struct rxkad_level2_hdr sechdr;
|
|
|
|
if (skb_copy_bits(skb, *_offset, &sechdr, sizeof(sechdr)) < 0)
|
|
BUG();
|
|
*_offset += sizeof(sechdr);
|
|
*_len = ntohl(sechdr.data_size) & 0xffff;
|
|
}
|
|
|
|
/*
|
|
* Locate the data contained in an already decrypted packet.
|
|
*/
|
|
static void rxkad_locate_data(struct rxrpc_call *call, struct sk_buff *skb,
|
|
unsigned int *_offset, unsigned int *_len)
|
|
{
|
|
switch (call->conn->params.security_level) {
|
|
case RXRPC_SECURITY_AUTH:
|
|
rxkad_locate_data_1(call, skb, _offset, _len);
|
|
return;
|
|
case RXRPC_SECURITY_ENCRYPT:
|
|
rxkad_locate_data_2(call, skb, _offset, _len);
|
|
return;
|
|
default:
|
|
return;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* issue a challenge
|
|
*/
|
|
static int rxkad_issue_challenge(struct rxrpc_connection *conn)
|
|
{
|
|
struct rxkad_challenge challenge;
|
|
struct rxrpc_wire_header whdr;
|
|
struct msghdr msg;
|
|
struct kvec iov[2];
|
|
size_t len;
|
|
u32 serial;
|
|
int ret;
|
|
|
|
_enter("{%d}", conn->debug_id);
|
|
|
|
get_random_bytes(&conn->rxkad.nonce, sizeof(conn->rxkad.nonce));
|
|
|
|
challenge.version = htonl(2);
|
|
challenge.nonce = htonl(conn->rxkad.nonce);
|
|
challenge.min_level = htonl(0);
|
|
challenge.__padding = 0;
|
|
|
|
msg.msg_name = &conn->params.peer->srx.transport;
|
|
msg.msg_namelen = conn->params.peer->srx.transport_len;
|
|
msg.msg_control = NULL;
|
|
msg.msg_controllen = 0;
|
|
msg.msg_flags = 0;
|
|
|
|
whdr.epoch = htonl(conn->proto.epoch);
|
|
whdr.cid = htonl(conn->proto.cid);
|
|
whdr.callNumber = 0;
|
|
whdr.seq = 0;
|
|
whdr.type = RXRPC_PACKET_TYPE_CHALLENGE;
|
|
whdr.flags = conn->out_clientflag;
|
|
whdr.userStatus = 0;
|
|
whdr.securityIndex = conn->security_ix;
|
|
whdr._rsvd = 0;
|
|
whdr.serviceId = htons(conn->service_id);
|
|
|
|
iov[0].iov_base = &whdr;
|
|
iov[0].iov_len = sizeof(whdr);
|
|
iov[1].iov_base = &challenge;
|
|
iov[1].iov_len = sizeof(challenge);
|
|
|
|
len = iov[0].iov_len + iov[1].iov_len;
|
|
|
|
serial = atomic_inc_return(&conn->serial);
|
|
whdr.serial = htonl(serial);
|
|
_proto("Tx CHALLENGE %%%u", serial);
|
|
|
|
ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
|
|
if (ret < 0) {
|
|
trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
|
|
rxrpc_tx_point_rxkad_challenge);
|
|
return -EAGAIN;
|
|
}
|
|
|
|
conn->params.peer->last_tx_at = ktime_get_seconds();
|
|
trace_rxrpc_tx_packet(conn->debug_id, &whdr,
|
|
rxrpc_tx_point_rxkad_challenge);
|
|
_leave(" = 0");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* send a Kerberos security response
|
|
*/
|
|
static int rxkad_send_response(struct rxrpc_connection *conn,
|
|
struct rxrpc_host_header *hdr,
|
|
struct rxkad_response *resp,
|
|
const struct rxkad_key *s2)
|
|
{
|
|
struct rxrpc_wire_header whdr;
|
|
struct msghdr msg;
|
|
struct kvec iov[3];
|
|
size_t len;
|
|
u32 serial;
|
|
int ret;
|
|
|
|
_enter("");
|
|
|
|
msg.msg_name = &conn->params.peer->srx.transport;
|
|
msg.msg_namelen = conn->params.peer->srx.transport_len;
|
|
msg.msg_control = NULL;
|
|
msg.msg_controllen = 0;
|
|
msg.msg_flags = 0;
|
|
|
|
memset(&whdr, 0, sizeof(whdr));
|
|
whdr.epoch = htonl(hdr->epoch);
|
|
whdr.cid = htonl(hdr->cid);
|
|
whdr.type = RXRPC_PACKET_TYPE_RESPONSE;
|
|
whdr.flags = conn->out_clientflag;
|
|
whdr.securityIndex = hdr->securityIndex;
|
|
whdr.serviceId = htons(hdr->serviceId);
|
|
|
|
iov[0].iov_base = &whdr;
|
|
iov[0].iov_len = sizeof(whdr);
|
|
iov[1].iov_base = resp;
|
|
iov[1].iov_len = sizeof(*resp);
|
|
iov[2].iov_base = (void *)s2->ticket;
|
|
iov[2].iov_len = s2->ticket_len;
|
|
|
|
len = iov[0].iov_len + iov[1].iov_len + iov[2].iov_len;
|
|
|
|
serial = atomic_inc_return(&conn->serial);
|
|
whdr.serial = htonl(serial);
|
|
_proto("Tx RESPONSE %%%u", serial);
|
|
|
|
ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 3, len);
|
|
if (ret < 0) {
|
|
trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
|
|
rxrpc_tx_point_rxkad_response);
|
|
return -EAGAIN;
|
|
}
|
|
|
|
conn->params.peer->last_tx_at = ktime_get_seconds();
|
|
_leave(" = 0");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* calculate the response checksum
|
|
*/
|
|
static void rxkad_calc_response_checksum(struct rxkad_response *response)
|
|
{
|
|
u32 csum = 1000003;
|
|
int loop;
|
|
u8 *p = (u8 *) response;
|
|
|
|
for (loop = sizeof(*response); loop > 0; loop--)
|
|
csum = csum * 0x10204081 + *p++;
|
|
|
|
response->encrypted.checksum = htonl(csum);
|
|
}
|
|
|
|
/*
|
|
* encrypt the response packet
|
|
*/
|
|
static int rxkad_encrypt_response(struct rxrpc_connection *conn,
|
|
struct rxkad_response *resp,
|
|
const struct rxkad_key *s2)
|
|
{
|
|
struct skcipher_request *req;
|
|
struct rxrpc_crypt iv;
|
|
struct scatterlist sg[1];
|
|
|
|
req = skcipher_request_alloc(&conn->rxkad.cipher->base, GFP_NOFS);
|
|
if (!req)
|
|
return -ENOMEM;
|
|
|
|
/* continue encrypting from where we left off */
|
|
memcpy(&iv, s2->session_key, sizeof(iv));
|
|
|
|
sg_init_table(sg, 1);
|
|
sg_set_buf(sg, &resp->encrypted, sizeof(resp->encrypted));
|
|
skcipher_request_set_sync_tfm(req, conn->rxkad.cipher);
|
|
skcipher_request_set_callback(req, 0, NULL, NULL);
|
|
skcipher_request_set_crypt(req, sg, sg, sizeof(resp->encrypted), iv.x);
|
|
crypto_skcipher_encrypt(req);
|
|
skcipher_request_free(req);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* respond to a challenge packet
|
|
*/
|
|
static int rxkad_respond_to_challenge(struct rxrpc_connection *conn,
|
|
struct sk_buff *skb,
|
|
u32 *_abort_code)
|
|
{
|
|
const struct rxrpc_key_token *token;
|
|
struct rxkad_challenge challenge;
|
|
struct rxkad_response *resp;
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
const char *eproto;
|
|
u32 version, nonce, min_level, abort_code;
|
|
int ret;
|
|
|
|
_enter("{%d,%x}", conn->debug_id, key_serial(conn->params.key));
|
|
|
|
eproto = tracepoint_string("chall_no_key");
|
|
abort_code = RX_PROTOCOL_ERROR;
|
|
if (!conn->params.key)
|
|
goto protocol_error;
|
|
|
|
abort_code = RXKADEXPIRED;
|
|
ret = key_validate(conn->params.key);
|
|
if (ret < 0)
|
|
goto other_error;
|
|
|
|
eproto = tracepoint_string("chall_short");
|
|
abort_code = RXKADPACKETSHORT;
|
|
if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
|
|
&challenge, sizeof(challenge)) < 0)
|
|
goto protocol_error;
|
|
|
|
version = ntohl(challenge.version);
|
|
nonce = ntohl(challenge.nonce);
|
|
min_level = ntohl(challenge.min_level);
|
|
|
|
_proto("Rx CHALLENGE %%%u { v=%u n=%u ml=%u }",
|
|
sp->hdr.serial, version, nonce, min_level);
|
|
|
|
eproto = tracepoint_string("chall_ver");
|
|
abort_code = RXKADINCONSISTENCY;
|
|
if (version != RXKAD_VERSION)
|
|
goto protocol_error;
|
|
|
|
abort_code = RXKADLEVELFAIL;
|
|
ret = -EACCES;
|
|
if (conn->params.security_level < min_level)
|
|
goto other_error;
|
|
|
|
token = conn->params.key->payload.data[0];
|
|
|
|
/* build the response packet */
|
|
resp = kzalloc(sizeof(struct rxkad_response), GFP_NOFS);
|
|
if (!resp)
|
|
return -ENOMEM;
|
|
|
|
resp->version = htonl(RXKAD_VERSION);
|
|
resp->encrypted.epoch = htonl(conn->proto.epoch);
|
|
resp->encrypted.cid = htonl(conn->proto.cid);
|
|
resp->encrypted.securityIndex = htonl(conn->security_ix);
|
|
resp->encrypted.inc_nonce = htonl(nonce + 1);
|
|
resp->encrypted.level = htonl(conn->params.security_level);
|
|
resp->kvno = htonl(token->kad->kvno);
|
|
resp->ticket_len = htonl(token->kad->ticket_len);
|
|
resp->encrypted.call_id[0] = htonl(conn->channels[0].call_counter);
|
|
resp->encrypted.call_id[1] = htonl(conn->channels[1].call_counter);
|
|
resp->encrypted.call_id[2] = htonl(conn->channels[2].call_counter);
|
|
resp->encrypted.call_id[3] = htonl(conn->channels[3].call_counter);
|
|
|
|
/* calculate the response checksum and then do the encryption */
|
|
rxkad_calc_response_checksum(resp);
|
|
ret = rxkad_encrypt_response(conn, resp, token->kad);
|
|
if (ret == 0)
|
|
ret = rxkad_send_response(conn, &sp->hdr, resp, token->kad);
|
|
kfree(resp);
|
|
return ret;
|
|
|
|
protocol_error:
|
|
trace_rxrpc_rx_eproto(NULL, sp->hdr.serial, eproto);
|
|
ret = -EPROTO;
|
|
other_error:
|
|
*_abort_code = abort_code;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* decrypt the kerberos IV ticket in the response
|
|
*/
|
|
static int rxkad_decrypt_ticket(struct rxrpc_connection *conn,
|
|
struct key *server_key,
|
|
struct sk_buff *skb,
|
|
void *ticket, size_t ticket_len,
|
|
struct rxrpc_crypt *_session_key,
|
|
time64_t *_expiry,
|
|
u32 *_abort_code)
|
|
{
|
|
struct skcipher_request *req;
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
struct rxrpc_crypt iv, key;
|
|
struct scatterlist sg[1];
|
|
struct in_addr addr;
|
|
unsigned int life;
|
|
const char *eproto;
|
|
time64_t issue, now;
|
|
bool little_endian;
|
|
int ret;
|
|
u32 abort_code;
|
|
u8 *p, *q, *name, *end;
|
|
|
|
_enter("{%d},{%x}", conn->debug_id, key_serial(server_key));
|
|
|
|
*_expiry = 0;
|
|
|
|
ASSERT(server_key->payload.data[0] != NULL);
|
|
ASSERTCMP((unsigned long) ticket & 7UL, ==, 0);
|
|
|
|
memcpy(&iv, &server_key->payload.data[2], sizeof(iv));
|
|
|
|
ret = -ENOMEM;
|
|
req = skcipher_request_alloc(server_key->payload.data[0], GFP_NOFS);
|
|
if (!req)
|
|
goto temporary_error;
|
|
|
|
sg_init_one(&sg[0], ticket, ticket_len);
|
|
skcipher_request_set_callback(req, 0, NULL, NULL);
|
|
skcipher_request_set_crypt(req, sg, sg, ticket_len, iv.x);
|
|
crypto_skcipher_decrypt(req);
|
|
skcipher_request_free(req);
|
|
|
|
p = ticket;
|
|
end = p + ticket_len;
|
|
|
|
#define Z(field) \
|
|
({ \
|
|
u8 *__str = p; \
|
|
eproto = tracepoint_string("rxkad_bad_"#field); \
|
|
q = memchr(p, 0, end - p); \
|
|
if (!q || q - p > (field##_SZ)) \
|
|
goto bad_ticket; \
|
|
for (; p < q; p++) \
|
|
if (!isprint(*p)) \
|
|
goto bad_ticket; \
|
|
p++; \
|
|
__str; \
|
|
})
|
|
|
|
/* extract the ticket flags */
|
|
_debug("KIV FLAGS: %x", *p);
|
|
little_endian = *p & 1;
|
|
p++;
|
|
|
|
/* extract the authentication name */
|
|
name = Z(ANAME);
|
|
_debug("KIV ANAME: %s", name);
|
|
|
|
/* extract the principal's instance */
|
|
name = Z(INST);
|
|
_debug("KIV INST : %s", name);
|
|
|
|
/* extract the principal's authentication domain */
|
|
name = Z(REALM);
|
|
_debug("KIV REALM: %s", name);
|
|
|
|
eproto = tracepoint_string("rxkad_bad_len");
|
|
if (end - p < 4 + 8 + 4 + 2)
|
|
goto bad_ticket;
|
|
|
|
/* get the IPv4 address of the entity that requested the ticket */
|
|
memcpy(&addr, p, sizeof(addr));
|
|
p += 4;
|
|
_debug("KIV ADDR : %pI4", &addr);
|
|
|
|
/* get the session key from the ticket */
|
|
memcpy(&key, p, sizeof(key));
|
|
p += 8;
|
|
_debug("KIV KEY : %08x %08x", ntohl(key.n[0]), ntohl(key.n[1]));
|
|
memcpy(_session_key, &key, sizeof(key));
|
|
|
|
/* get the ticket's lifetime */
|
|
life = *p++ * 5 * 60;
|
|
_debug("KIV LIFE : %u", life);
|
|
|
|
/* get the issue time of the ticket */
|
|
if (little_endian) {
|
|
__le32 stamp;
|
|
memcpy(&stamp, p, 4);
|
|
issue = rxrpc_u32_to_time64(le32_to_cpu(stamp));
|
|
} else {
|
|
__be32 stamp;
|
|
memcpy(&stamp, p, 4);
|
|
issue = rxrpc_u32_to_time64(be32_to_cpu(stamp));
|
|
}
|
|
p += 4;
|
|
now = ktime_get_real_seconds();
|
|
_debug("KIV ISSUE: %llx [%llx]", issue, now);
|
|
|
|
/* check the ticket is in date */
|
|
if (issue > now) {
|
|
abort_code = RXKADNOAUTH;
|
|
ret = -EKEYREJECTED;
|
|
goto other_error;
|
|
}
|
|
|
|
if (issue < now - life) {
|
|
abort_code = RXKADEXPIRED;
|
|
ret = -EKEYEXPIRED;
|
|
goto other_error;
|
|
}
|
|
|
|
*_expiry = issue + life;
|
|
|
|
/* get the service name */
|
|
name = Z(SNAME);
|
|
_debug("KIV SNAME: %s", name);
|
|
|
|
/* get the service instance name */
|
|
name = Z(INST);
|
|
_debug("KIV SINST: %s", name);
|
|
return 0;
|
|
|
|
bad_ticket:
|
|
trace_rxrpc_rx_eproto(NULL, sp->hdr.serial, eproto);
|
|
abort_code = RXKADBADTICKET;
|
|
ret = -EPROTO;
|
|
other_error:
|
|
*_abort_code = abort_code;
|
|
return ret;
|
|
temporary_error:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* decrypt the response packet
|
|
*/
|
|
static void rxkad_decrypt_response(struct rxrpc_connection *conn,
|
|
struct rxkad_response *resp,
|
|
const struct rxrpc_crypt *session_key)
|
|
{
|
|
struct skcipher_request *req = rxkad_ci_req;
|
|
struct scatterlist sg[1];
|
|
struct rxrpc_crypt iv;
|
|
|
|
_enter(",,%08x%08x",
|
|
ntohl(session_key->n[0]), ntohl(session_key->n[1]));
|
|
|
|
mutex_lock(&rxkad_ci_mutex);
|
|
if (crypto_sync_skcipher_setkey(rxkad_ci, session_key->x,
|
|
sizeof(*session_key)) < 0)
|
|
BUG();
|
|
|
|
memcpy(&iv, session_key, sizeof(iv));
|
|
|
|
sg_init_table(sg, 1);
|
|
sg_set_buf(sg, &resp->encrypted, sizeof(resp->encrypted));
|
|
skcipher_request_set_sync_tfm(req, rxkad_ci);
|
|
skcipher_request_set_callback(req, 0, NULL, NULL);
|
|
skcipher_request_set_crypt(req, sg, sg, sizeof(resp->encrypted), iv.x);
|
|
crypto_skcipher_decrypt(req);
|
|
skcipher_request_zero(req);
|
|
|
|
mutex_unlock(&rxkad_ci_mutex);
|
|
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* verify a response
|
|
*/
|
|
static int rxkad_verify_response(struct rxrpc_connection *conn,
|
|
struct sk_buff *skb,
|
|
u32 *_abort_code)
|
|
{
|
|
struct rxkad_response *response;
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
struct rxrpc_crypt session_key;
|
|
struct key *server_key;
|
|
const char *eproto;
|
|
time64_t expiry;
|
|
void *ticket;
|
|
u32 abort_code, version, kvno, ticket_len, level;
|
|
__be32 csum;
|
|
int ret, i;
|
|
|
|
_enter("{%d}", conn->debug_id);
|
|
|
|
server_key = rxrpc_look_up_server_security(conn, skb, 0, 0);
|
|
if (IS_ERR(server_key)) {
|
|
switch (PTR_ERR(server_key)) {
|
|
case -ENOKEY:
|
|
abort_code = RXKADUNKNOWNKEY;
|
|
break;
|
|
case -EKEYEXPIRED:
|
|
abort_code = RXKADEXPIRED;
|
|
break;
|
|
default:
|
|
abort_code = RXKADNOAUTH;
|
|
break;
|
|
}
|
|
trace_rxrpc_abort(0, "SVK",
|
|
sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
|
|
abort_code, PTR_ERR(server_key));
|
|
*_abort_code = abort_code;
|
|
return -EPROTO;
|
|
}
|
|
|
|
ret = -ENOMEM;
|
|
response = kzalloc(sizeof(struct rxkad_response), GFP_NOFS);
|
|
if (!response)
|
|
goto temporary_error;
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_short");
|
|
abort_code = RXKADPACKETSHORT;
|
|
if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
|
|
response, sizeof(*response)) < 0)
|
|
goto protocol_error;
|
|
|
|
version = ntohl(response->version);
|
|
ticket_len = ntohl(response->ticket_len);
|
|
kvno = ntohl(response->kvno);
|
|
_proto("Rx RESPONSE %%%u { v=%u kv=%u tl=%u }",
|
|
sp->hdr.serial, version, kvno, ticket_len);
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_ver");
|
|
abort_code = RXKADINCONSISTENCY;
|
|
if (version != RXKAD_VERSION)
|
|
goto protocol_error;
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_tktlen");
|
|
abort_code = RXKADTICKETLEN;
|
|
if (ticket_len < 4 || ticket_len > MAXKRB5TICKETLEN)
|
|
goto protocol_error;
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_unkkey");
|
|
abort_code = RXKADUNKNOWNKEY;
|
|
if (kvno >= RXKAD_TKT_TYPE_KERBEROS_V5)
|
|
goto protocol_error;
|
|
|
|
/* extract the kerberos ticket and decrypt and decode it */
|
|
ret = -ENOMEM;
|
|
ticket = kmalloc(ticket_len, GFP_NOFS);
|
|
if (!ticket)
|
|
goto temporary_error_free_resp;
|
|
|
|
eproto = tracepoint_string("rxkad_tkt_short");
|
|
abort_code = RXKADPACKETSHORT;
|
|
if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header) + sizeof(*response),
|
|
ticket, ticket_len) < 0)
|
|
goto protocol_error_free;
|
|
|
|
ret = rxkad_decrypt_ticket(conn, server_key, skb, ticket, ticket_len,
|
|
&session_key, &expiry, _abort_code);
|
|
if (ret < 0)
|
|
goto temporary_error_free_ticket;
|
|
|
|
/* use the session key from inside the ticket to decrypt the
|
|
* response */
|
|
rxkad_decrypt_response(conn, response, &session_key);
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_param");
|
|
abort_code = RXKADSEALEDINCON;
|
|
if (ntohl(response->encrypted.epoch) != conn->proto.epoch)
|
|
goto protocol_error_free;
|
|
if (ntohl(response->encrypted.cid) != conn->proto.cid)
|
|
goto protocol_error_free;
|
|
if (ntohl(response->encrypted.securityIndex) != conn->security_ix)
|
|
goto protocol_error_free;
|
|
csum = response->encrypted.checksum;
|
|
response->encrypted.checksum = 0;
|
|
rxkad_calc_response_checksum(response);
|
|
eproto = tracepoint_string("rxkad_rsp_csum");
|
|
if (response->encrypted.checksum != csum)
|
|
goto protocol_error_free;
|
|
|
|
spin_lock(&conn->bundle->channel_lock);
|
|
for (i = 0; i < RXRPC_MAXCALLS; i++) {
|
|
struct rxrpc_call *call;
|
|
u32 call_id = ntohl(response->encrypted.call_id[i]);
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_callid");
|
|
if (call_id > INT_MAX)
|
|
goto protocol_error_unlock;
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_callctr");
|
|
if (call_id < conn->channels[i].call_counter)
|
|
goto protocol_error_unlock;
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_callst");
|
|
if (call_id > conn->channels[i].call_counter) {
|
|
call = rcu_dereference_protected(
|
|
conn->channels[i].call,
|
|
lockdep_is_held(&conn->bundle->channel_lock));
|
|
if (call && call->state < RXRPC_CALL_COMPLETE)
|
|
goto protocol_error_unlock;
|
|
conn->channels[i].call_counter = call_id;
|
|
}
|
|
}
|
|
spin_unlock(&conn->bundle->channel_lock);
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_seq");
|
|
abort_code = RXKADOUTOFSEQUENCE;
|
|
if (ntohl(response->encrypted.inc_nonce) != conn->rxkad.nonce + 1)
|
|
goto protocol_error_free;
|
|
|
|
eproto = tracepoint_string("rxkad_rsp_level");
|
|
abort_code = RXKADLEVELFAIL;
|
|
level = ntohl(response->encrypted.level);
|
|
if (level > RXRPC_SECURITY_ENCRYPT)
|
|
goto protocol_error_free;
|
|
conn->params.security_level = level;
|
|
|
|
/* create a key to hold the security data and expiration time - after
|
|
* this the connection security can be handled in exactly the same way
|
|
* as for a client connection */
|
|
ret = rxrpc_get_server_data_key(conn, &session_key, expiry, kvno);
|
|
if (ret < 0)
|
|
goto temporary_error_free_ticket;
|
|
|
|
kfree(ticket);
|
|
kfree(response);
|
|
_leave(" = 0");
|
|
return 0;
|
|
|
|
protocol_error_unlock:
|
|
spin_unlock(&conn->bundle->channel_lock);
|
|
protocol_error_free:
|
|
kfree(ticket);
|
|
protocol_error:
|
|
kfree(response);
|
|
trace_rxrpc_rx_eproto(NULL, sp->hdr.serial, eproto);
|
|
key_put(server_key);
|
|
*_abort_code = abort_code;
|
|
return -EPROTO;
|
|
|
|
temporary_error_free_ticket:
|
|
kfree(ticket);
|
|
temporary_error_free_resp:
|
|
kfree(response);
|
|
temporary_error:
|
|
/* Ignore the response packet if we got a temporary error such as
|
|
* ENOMEM. We just want to send the challenge again. Note that we
|
|
* also come out this way if the ticket decryption fails.
|
|
*/
|
|
key_put(server_key);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* clear the connection security
|
|
*/
|
|
static void rxkad_clear(struct rxrpc_connection *conn)
|
|
{
|
|
_enter("");
|
|
|
|
if (conn->rxkad.cipher)
|
|
crypto_free_sync_skcipher(conn->rxkad.cipher);
|
|
}
|
|
|
|
/*
|
|
* Initialise the rxkad security service.
|
|
*/
|
|
static int rxkad_init(void)
|
|
{
|
|
struct crypto_sync_skcipher *tfm;
|
|
struct skcipher_request *req;
|
|
|
|
/* pin the cipher we need so that the crypto layer doesn't invoke
|
|
* keventd to go get it */
|
|
tfm = crypto_alloc_sync_skcipher("pcbc(fcrypt)", 0, 0);
|
|
if (IS_ERR(tfm))
|
|
return PTR_ERR(tfm);
|
|
|
|
req = skcipher_request_alloc(&tfm->base, GFP_KERNEL);
|
|
if (!req)
|
|
goto nomem_tfm;
|
|
|
|
rxkad_ci_req = req;
|
|
rxkad_ci = tfm;
|
|
return 0;
|
|
|
|
nomem_tfm:
|
|
crypto_free_sync_skcipher(tfm);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* Clean up the rxkad security service.
|
|
*/
|
|
static void rxkad_exit(void)
|
|
{
|
|
crypto_free_sync_skcipher(rxkad_ci);
|
|
skcipher_request_free(rxkad_ci_req);
|
|
}
|
|
|
|
/*
|
|
* RxRPC Kerberos-based security
|
|
*/
|
|
const struct rxrpc_security rxkad = {
|
|
.name = "rxkad",
|
|
.security_index = RXRPC_SECURITY_RXKAD,
|
|
.no_key_abort = RXKADUNKNOWNKEY,
|
|
.init = rxkad_init,
|
|
.exit = rxkad_exit,
|
|
.preparse_server_key = rxkad_preparse_server_key,
|
|
.free_preparse_server_key = rxkad_free_preparse_server_key,
|
|
.destroy_server_key = rxkad_destroy_server_key,
|
|
.init_connection_security = rxkad_init_connection_security,
|
|
.how_much_data = rxkad_how_much_data,
|
|
.secure_packet = rxkad_secure_packet,
|
|
.verify_packet = rxkad_verify_packet,
|
|
.free_call_crypto = rxkad_free_call_crypto,
|
|
.locate_data = rxkad_locate_data,
|
|
.issue_challenge = rxkad_issue_challenge,
|
|
.respond_to_challenge = rxkad_respond_to_challenge,
|
|
.verify_response = rxkad_verify_response,
|
|
.clear = rxkad_clear,
|
|
};
|