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 000000000000..7e049ff6ae60
--- /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);