diff options
Diffstat (limited to 'net/rxrpc/server_key.c')
| -rw-r--r-- | net/rxrpc/server_key.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/net/rxrpc/server_key.c b/net/rxrpc/server_key.c new file mode 100644 index 0000000000..e51940589e --- /dev/null +++ b/net/rxrpc/server_key.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* RxRPC key management + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * RxRPC keys should have a description of describing their purpose: + * "afs@CAMBRIDGE.REDHAT.COM> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <crypto/skcipher.h> +#include <linux/module.h> +#include <linux/net.h> +#include <linux/skbuff.h> +#include <linux/key-type.h> +#include <linux/ctype.h> +#include <linux/slab.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_vet_description_s(const char *); +static int rxrpc_preparse_s(struct key_preparsed_payload *); +static void rxrpc_free_preparse_s(struct key_preparsed_payload *); +static void rxrpc_destroy_s(struct key *); +static void rxrpc_describe_s(const struct key *, struct seq_file *); + +/* + * rxrpc server keys take "<serviceId>:<securityIndex>[:<sec-specific>]" as the + * description and the key material as the payload. + */ +struct key_type key_type_rxrpc_s = { + .name = "rxrpc_s", + .flags = KEY_TYPE_NET_DOMAIN, + .vet_description = rxrpc_vet_description_s, + .preparse = rxrpc_preparse_s, + .free_preparse = rxrpc_free_preparse_s, + .instantiate = generic_key_instantiate, + .destroy = rxrpc_destroy_s, + .describe = rxrpc_describe_s, +}; + +/* + * Vet the description for an RxRPC server key. + */ +static int rxrpc_vet_description_s(const char *desc) +{ + unsigned long service, sec_class; + char *p; + + service = simple_strtoul(desc, &p, 10); + if (*p != ':' || service > 65535) + return -EINVAL; + sec_class = simple_strtoul(p + 1, &p, 10); + if ((*p && *p != ':') || sec_class < 1 || sec_class > 255) + return -EINVAL; + return 0; +} + +/* + * Preparse a server secret key. + */ +static int rxrpc_preparse_s(struct key_preparsed_payload *prep) +{ + const struct rxrpc_security *sec; + unsigned int service, sec_class; + int n; + + _enter("%zu", prep->datalen); + + if (!prep->orig_description) + return -EINVAL; + + if (sscanf(prep->orig_description, "%u:%u%n", &service, &sec_class, &n) != 2) + return -EINVAL; + + sec = rxrpc_security_lookup(sec_class); + if (!sec) + return -ENOPKG; + + prep->payload.data[1] = (struct rxrpc_security *)sec; + + if (!sec->preparse_server_key) + return -EINVAL; + + return sec->preparse_server_key(prep); +} + +static void rxrpc_free_preparse_s(struct key_preparsed_payload *prep) +{ + const struct rxrpc_security *sec = prep->payload.data[1]; + + if (sec && sec->free_preparse_server_key) + sec->free_preparse_server_key(prep); +} + +static void rxrpc_destroy_s(struct key *key) +{ + const struct rxrpc_security *sec = key->payload.data[1]; + + if (sec && sec->destroy_server_key) + sec->destroy_server_key(key); +} + +static void rxrpc_describe_s(const struct key *key, struct seq_file *m) +{ + const struct rxrpc_security *sec = key->payload.data[1]; + + seq_puts(m, key->description); + if (sec && sec->describe_server_key) + sec->describe_server_key(key, m); +} + +/* + * grab the security keyring for a server socket + */ +int rxrpc_server_keyring(struct rxrpc_sock *rx, sockptr_t optval, int optlen) +{ + struct key *key; + char *description; + + _enter(""); + + if (optlen <= 0 || optlen > PAGE_SIZE - 1) + return -EINVAL; + + description = memdup_sockptr_nul(optval, optlen); + if (IS_ERR(description)) + return PTR_ERR(description); + + 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; +} + +/** + * rxrpc_sock_set_security_keyring - Set the security keyring for a kernel service + * @sk: The socket to set the keyring on + * @keyring: The keyring to set + * + * Set the server security keyring on an rxrpc socket. This is used to provide + * the encryption keys for a kernel service. + */ +int rxrpc_sock_set_security_keyring(struct sock *sk, struct key *keyring) +{ + struct rxrpc_sock *rx = rxrpc_sk(sk); + int ret = 0; + + lock_sock(sk); + if (rx->securities) + ret = -EINVAL; + else if (rx->sk.sk_state != RXRPC_UNBOUND) + ret = -EISCONN; + else + rx->securities = key_get(keyring); + release_sock(sk); + return ret; +} +EXPORT_SYMBOL(rxrpc_sock_set_security_keyring); |