1 files changed, 334 insertions, 0 deletions
diff --git a/net/rxrpc/ar-key.c b/net/rxrpc/ar-key.c
new file mode 100644
index 0000000..7e049ff
--- /dev/null
+++ b/net/rxrpc/ar-key.c
@@ -0,0 +1,334 @@
+/* RxRPC key management
+ *
+ * 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.
+ *
+ * RxRPC keys should have a description of describing their purpose:
+ *	"afs@CAMBRIDGE.REDHAT.COM>
+ */
+
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/skbuff.h>
+#include <linux/key.h>
+#include <linux/crypto.h>
+#include <net/sock.h>
+#include <net/af_rxrpc.h>
+#include <keys/rxrpc-type.h>
+#include <keys/user-type.h>
+#include "ar-internal.h"
+
+static int rxrpc_instantiate(struct key *, const void *, size_t);
+static int rxrpc_instantiate_s(struct key *, const void *, size_t);
+static void rxrpc_destroy(struct key *);
+static void rxrpc_destroy_s(struct key *);
+static void rxrpc_describe(const struct key *, struct seq_file *);
+
+/*
+ * rxrpc defined keys take an arbitrary string as the description and an
+ * arbitrary blob of data as the payload
+ */
+struct key_type key_type_rxrpc = {
+	.name		= "rxrpc",
+	.instantiate	= rxrpc_instantiate,
+	.match		= user_match,
+	.destroy	= rxrpc_destroy,
+	.describe	= rxrpc_describe,
+};
+
+EXPORT_SYMBOL(key_type_rxrpc);
+
+/*
+ * rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
+ * description and an 8-byte decryption key as the payload
+ */
+struct key_type key_type_rxrpc_s = {
+	.name		= "rxrpc_s",
+	.instantiate	= rxrpc_instantiate_s,
+	.match		= user_match,
+	.destroy	= rxrpc_destroy_s,
+	.describe	= rxrpc_describe,
+};
+
+/*
+ * instantiate an rxrpc defined key
+ * data should be of the form:
+ *	OFFSET	LEN	CONTENT
+ *	0	4	key interface version number
+ *	4	2	security index (type)
+ *	6	2	ticket length
+ *	8	4	key expiry time (time_t)
+ *	12	4	kvno
+ *	16	8	session key
+ *	24	[len]	ticket
+ *
+ * if no data is provided, then a no-security key is made
+ */
+static int rxrpc_instantiate(struct key *key, const void *data, size_t datalen)
+{
+	const struct rxkad_key *tsec;
+	struct rxrpc_key_payload *upayload;
+	size_t plen;
+	u32 kver;
+	int ret;
+
+	_enter("{%x},,%zu", key_serial(key), datalen);
+
+	/* handle a no-security key */
+	if (!data && datalen == 0)
+		return 0;
+
+	/* get the key interface version number */
+	ret = -EINVAL;
+	if (datalen <= 4 || !data)
+		goto error;
+	memcpy(&kver, data, sizeof(kver));
+	data += sizeof(kver);
+	datalen -= sizeof(kver);
+
+	_debug("KEY I/F VERSION: %u", kver);
+
+	ret = -EKEYREJECTED;
+	if (kver != 1)
+		goto error;
+
+	/* deal with a version 1 key */
+	ret = -EINVAL;
+	if (datalen < sizeof(*tsec))
+		goto error;
+
+	tsec = data;
+	if (datalen != sizeof(*tsec) + tsec->ticket_len)
+		goto error;
+
+	_debug("SCIX: %u", tsec->security_index);
+	_debug("TLEN: %u", tsec->ticket_len);
+	_debug("EXPY: %x", tsec->expiry);
+	_debug("KVNO: %u", tsec->kvno);
+	_debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
+	       tsec->session_key[0], tsec->session_key[1],
+	       tsec->session_key[2], tsec->session_key[3],
+	       tsec->session_key[4], tsec->session_key[5],
+	       tsec->session_key[6], tsec->session_key[7]);
+	if (tsec->ticket_len >= 8)
+		_debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
+		       tsec->ticket[0], tsec->ticket[1],
+		       tsec->ticket[2], tsec->ticket[3],
+		       tsec->ticket[4], tsec->ticket[5],
+		       tsec->ticket[6], tsec->ticket[7]);
+
+	ret = -EPROTONOSUPPORT;
+	if (tsec->security_index != 2)
+		goto error;
+
+	key->type_data.x[0] = tsec->security_index;
+
+	plen = sizeof(*upayload) + tsec->ticket_len;
+	ret = key_payload_reserve(key, plen);
+	if (ret < 0)
+		goto error;
+
+	ret = -ENOMEM;
+	upayload = kmalloc(plen, GFP_KERNEL);
+	if (!upayload)
+		goto error;
+
+	/* attach the data */
+	memcpy(&upayload->k, tsec, sizeof(*tsec));
+	memcpy(&upayload->k.ticket, (void *)tsec + sizeof(*tsec),
+	       tsec->ticket_len);
+	key->payload.data = upayload;
+	key->expiry = tsec->expiry;
+	ret = 0;
+
+error:
+	return ret;
+}
+
+/*
+ * instantiate a server secret key
+ * data should be a pointer to the 8-byte secret key
+ */
+static int rxrpc_instantiate_s(struct key *key, const void *data,
+			       size_t datalen)
+{
+	struct crypto_blkcipher *ci;
+
+	_enter("{%x},,%zu", key_serial(key), datalen);
+
+	if (datalen != 8)
+		return -EINVAL;
+
+	memcpy(&key->type_data, data, 8);
+
+	ci = crypto_alloc_blkcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(ci)) {
+		_leave(" = %ld", PTR_ERR(ci));
+		return PTR_ERR(ci);
+	}
+
+	if (crypto_blkcipher_setkey(ci, data, 8) < 0)
+		BUG();
+
+	key->payload.data = ci;
+	_leave(" = 0");
+	return 0;
+}
+
+/*
+ * dispose of the data dangling from the corpse of a rxrpc key
+ */
+static void rxrpc_destroy(struct key *key)
+{
+	kfree(key->payload.data);
+}
+
+/*
+ * dispose of the data dangling from the corpse of a rxrpc key
+ */
+static void rxrpc_destroy_s(struct key *key)
+{
+	if (key->payload.data) {
+		crypto_free_blkcipher(key->payload.data);
+		key->payload.data = NULL;
+	}
+}
+
+/*
+ * describe the rxrpc key
+ */
+static void rxrpc_describe(const struct key *key, struct seq_file *m)
+{
+	seq_puts(m, key->description);
+}
+
+/*
+ * grab the security key for a socket
+ */
+int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
+{
+	struct key *key;
+	char *description;
+
+	_enter("");
+
+	if (optlen <= 0 || optlen > PAGE_SIZE - 1)
+		return -EINVAL;
+
+	description = kmalloc(optlen + 1, GFP_KERNEL);
+	if (!description)
+		return -ENOMEM;
+
+	if (copy_from_user(description, optval, optlen)) {
+		kfree(description);
+		return -EFAULT;
+	}
+	description[optlen] = 0;
+
+	key = request_key(&key_type_rxrpc, description, NULL);
+	if (IS_ERR(key)) {
+		kfree(description);
+		_leave(" = %ld", PTR_ERR(key));
+		return PTR_ERR(key);
+	}
+
+	rx->key = key;
+	kfree(description);
+	_leave(" = 0 [key %x]", key->serial);
+	return 0;
+}
+
+/*
+ * grab the security keyring for a server socket
+ */
+int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
+			 int optlen)
+{
+	struct key *key;
+	char *description;
+
+	_enter("");
+
+	if (optlen <= 0 || optlen > PAGE_SIZE - 1)
+		return -EINVAL;
+
+	description = kmalloc(optlen + 1, GFP_KERNEL);
+	if (!description)
+		return -ENOMEM;
+
+	if (copy_from_user(description, optval, optlen)) {
+		kfree(description);
+		return -EFAULT;
+	}
+	description[optlen] = 0;
+
+	key = request_key(&key_type_keyring, description, NULL);
+	if (IS_ERR(key)) {
+		kfree(description);
+		_leave(" = %ld", PTR_ERR(key));
+		return PTR_ERR(key);
+	}
+
+	rx->securities = key;
+	kfree(description);
+	_leave(" = 0 [key %x]", key->serial);
+	return 0;
+}
+
+/*
+ * generate a server data key
+ */
+int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
+			      const void *session_key,
+			      time_t expiry,
+			      u32 kvno)
+{
+	struct key *key;
+	int ret;
+
+	struct {
+		u32 kver;
+		struct rxkad_key tsec;
+	} data;
+
+	_enter("");
+
+	key = key_alloc(&key_type_rxrpc, "x", 0, 0, current, 0,
+			KEY_ALLOC_NOT_IN_QUOTA);
+	if (IS_ERR(key)) {
+		_leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
+		return -ENOMEM;
+	}
+
+	_debug("key %d", key_serial(key));
+
+	data.kver = 1;
+	data.tsec.security_index = 2;
+	data.tsec.ticket_len = 0;
+	data.tsec.expiry = expiry;
+	data.tsec.kvno = 0;
+
+	memcpy(&data.tsec.session_key, session_key,
+	       sizeof(data.tsec.session_key));
+
+	ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
+	if (ret < 0)
+		goto error;
+
+	conn->key = key;
+	_leave(" = 0 [%d]", key_serial(key));
+	return 0;
+
+error:
+	key_revoke(key);
+	key_put(key);
+	_leave(" = -ENOMEM [ins %d]", ret);
+	return -ENOMEM;
+}
+
+EXPORT_SYMBOL(rxrpc_get_server_data_key);