From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- crypto/algif_skcipher.c | 374 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 374 insertions(+) create mode 100644 crypto/algif_skcipher.c (limited to 'crypto/algif_skcipher.c') diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c new file mode 100644 index 0000000000..9ada9b741a --- /dev/null +++ b/crypto/algif_skcipher.c @@ -0,0 +1,374 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * algif_skcipher: User-space interface for skcipher algorithms + * + * This file provides the user-space API for symmetric key ciphers. + * + * Copyright (c) 2010 Herbert Xu + * + * The following concept of the memory management is used: + * + * The kernel maintains two SGLs, the TX SGL and the RX SGL. The TX SGL is + * filled by user space with the data submitted via sendmsg. Filling up the TX + * SGL does not cause a crypto operation -- the data will only be tracked by + * the kernel. Upon receipt of one recvmsg call, the caller must provide a + * buffer which is tracked with the RX SGL. + * + * During the processing of the recvmsg operation, the cipher request is + * allocated and prepared. As part of the recvmsg operation, the processed + * TX buffers are extracted from the TX SGL into a separate SGL. + * + * After the completion of the crypto operation, the RX SGL and the cipher + * request is released. The extracted TX SGL parts are released together with + * the RX SGL release. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static int skcipher_sendmsg(struct socket *sock, struct msghdr *msg, + size_t size) +{ + struct sock *sk = sock->sk; + struct alg_sock *ask = alg_sk(sk); + struct sock *psk = ask->parent; + struct alg_sock *pask = alg_sk(psk); + struct crypto_skcipher *tfm = pask->private; + unsigned ivsize = crypto_skcipher_ivsize(tfm); + + return af_alg_sendmsg(sock, msg, size, ivsize); +} + +static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg, + size_t ignored, int flags) +{ + struct sock *sk = sock->sk; + struct alg_sock *ask = alg_sk(sk); + struct sock *psk = ask->parent; + struct alg_sock *pask = alg_sk(psk); + struct af_alg_ctx *ctx = ask->private; + struct crypto_skcipher *tfm = pask->private; + unsigned int bs = crypto_skcipher_chunksize(tfm); + struct af_alg_async_req *areq; + int err = 0; + size_t len = 0; + + if (!ctx->init || (ctx->more && ctx->used < bs)) { + err = af_alg_wait_for_data(sk, flags, bs); + if (err) + return err; + } + + /* Allocate cipher request for current operation. */ + areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) + + crypto_skcipher_reqsize(tfm)); + if (IS_ERR(areq)) + return PTR_ERR(areq); + + /* convert iovecs of output buffers into RX SGL */ + err = af_alg_get_rsgl(sk, msg, flags, areq, ctx->used, &len); + if (err) + goto free; + + /* + * If more buffers are to be expected to be processed, process only + * full block size buffers. + */ + if (ctx->more || len < ctx->used) + len -= len % bs; + + /* + * Create a per request TX SGL for this request which tracks the + * SG entries from the global TX SGL. + */ + areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0); + if (!areq->tsgl_entries) + areq->tsgl_entries = 1; + areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl), + areq->tsgl_entries), + GFP_KERNEL); + if (!areq->tsgl) { + err = -ENOMEM; + goto free; + } + sg_init_table(areq->tsgl, areq->tsgl_entries); + af_alg_pull_tsgl(sk, len, areq->tsgl, 0); + + /* Initialize the crypto operation */ + skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm); + skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl, + areq->first_rsgl.sgl.sgt.sgl, len, ctx->iv); + + if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) { + /* AIO operation */ + sock_hold(sk); + areq->iocb = msg->msg_iocb; + + /* Remember output size that will be generated. */ + areq->outlen = len; + + skcipher_request_set_callback(&areq->cra_u.skcipher_req, + CRYPTO_TFM_REQ_MAY_SLEEP, + af_alg_async_cb, areq); + err = ctx->enc ? + crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) : + crypto_skcipher_decrypt(&areq->cra_u.skcipher_req); + + /* AIO operation in progress */ + if (err == -EINPROGRESS) + return -EIOCBQUEUED; + + sock_put(sk); + } else { + /* Synchronous operation */ + skcipher_request_set_callback(&areq->cra_u.skcipher_req, + CRYPTO_TFM_REQ_MAY_SLEEP | + CRYPTO_TFM_REQ_MAY_BACKLOG, + crypto_req_done, &ctx->wait); + err = crypto_wait_req(ctx->enc ? + crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) : + crypto_skcipher_decrypt(&areq->cra_u.skcipher_req), + &ctx->wait); + } + + +free: + af_alg_free_resources(areq); + + return err ? err : len; +} + +static int skcipher_recvmsg(struct socket *sock, struct msghdr *msg, + size_t ignored, int flags) +{ + struct sock *sk = sock->sk; + int ret = 0; + + lock_sock(sk); + while (msg_data_left(msg)) { + int err = _skcipher_recvmsg(sock, msg, ignored, flags); + + /* + * This error covers -EIOCBQUEUED which implies that we can + * only handle one AIO request. If the caller wants to have + * multiple AIO requests in parallel, he must make multiple + * separate AIO calls. + * + * Also return the error if no data has been processed so far. + */ + if (err <= 0) { + if (err == -EIOCBQUEUED || !ret) + ret = err; + goto out; + } + + ret += err; + } + +out: + af_alg_wmem_wakeup(sk); + release_sock(sk); + return ret; +} + +static struct proto_ops algif_skcipher_ops = { + .family = PF_ALG, + + .connect = sock_no_connect, + .socketpair = sock_no_socketpair, + .getname = sock_no_getname, + .ioctl = sock_no_ioctl, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .mmap = sock_no_mmap, + .bind = sock_no_bind, + .accept = sock_no_accept, + + .release = af_alg_release, + .sendmsg = skcipher_sendmsg, + .recvmsg = skcipher_recvmsg, + .poll = af_alg_poll, +}; + +static int skcipher_check_key(struct socket *sock) +{ + int err = 0; + struct sock *psk; + struct alg_sock *pask; + struct crypto_skcipher *tfm; + struct sock *sk = sock->sk; + struct alg_sock *ask = alg_sk(sk); + + lock_sock(sk); + if (!atomic_read(&ask->nokey_refcnt)) + goto unlock_child; + + psk = ask->parent; + pask = alg_sk(ask->parent); + tfm = pask->private; + + err = -ENOKEY; + lock_sock_nested(psk, SINGLE_DEPTH_NESTING); + if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) + goto unlock; + + atomic_dec(&pask->nokey_refcnt); + atomic_set(&ask->nokey_refcnt, 0); + + err = 0; + +unlock: + release_sock(psk); +unlock_child: + release_sock(sk); + + return err; +} + +static int skcipher_sendmsg_nokey(struct socket *sock, struct msghdr *msg, + size_t size) +{ + int err; + + err = skcipher_check_key(sock); + if (err) + return err; + + return skcipher_sendmsg(sock, msg, size); +} + +static int skcipher_recvmsg_nokey(struct socket *sock, struct msghdr *msg, + size_t ignored, int flags) +{ + int err; + + err = skcipher_check_key(sock); + if (err) + return err; + + return skcipher_recvmsg(sock, msg, ignored, flags); +} + +static struct proto_ops algif_skcipher_ops_nokey = { + .family = PF_ALG, + + .connect = sock_no_connect, + .socketpair = sock_no_socketpair, + .getname = sock_no_getname, + .ioctl = sock_no_ioctl, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .mmap = sock_no_mmap, + .bind = sock_no_bind, + .accept = sock_no_accept, + + .release = af_alg_release, + .sendmsg = skcipher_sendmsg_nokey, + .recvmsg = skcipher_recvmsg_nokey, + .poll = af_alg_poll, +}; + +static void *skcipher_bind(const char *name, u32 type, u32 mask) +{ + return crypto_alloc_skcipher(name, type, mask); +} + +static void skcipher_release(void *private) +{ + crypto_free_skcipher(private); +} + +static int skcipher_setkey(void *private, const u8 *key, unsigned int keylen) +{ + return crypto_skcipher_setkey(private, key, keylen); +} + +static void skcipher_sock_destruct(struct sock *sk) +{ + struct alg_sock *ask = alg_sk(sk); + struct af_alg_ctx *ctx = ask->private; + struct sock *psk = ask->parent; + struct alg_sock *pask = alg_sk(psk); + struct crypto_skcipher *tfm = pask->private; + + af_alg_pull_tsgl(sk, ctx->used, NULL, 0); + sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm)); + sock_kfree_s(sk, ctx, ctx->len); + af_alg_release_parent(sk); +} + +static int skcipher_accept_parent_nokey(void *private, struct sock *sk) +{ + struct af_alg_ctx *ctx; + struct alg_sock *ask = alg_sk(sk); + struct crypto_skcipher *tfm = private; + unsigned int len = sizeof(*ctx); + + ctx = sock_kmalloc(sk, len, GFP_KERNEL); + if (!ctx) + return -ENOMEM; + memset(ctx, 0, len); + + ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(tfm), + GFP_KERNEL); + if (!ctx->iv) { + sock_kfree_s(sk, ctx, len); + return -ENOMEM; + } + memset(ctx->iv, 0, crypto_skcipher_ivsize(tfm)); + + INIT_LIST_HEAD(&ctx->tsgl_list); + ctx->len = len; + crypto_init_wait(&ctx->wait); + + ask->private = ctx; + + sk->sk_destruct = skcipher_sock_destruct; + + return 0; +} + +static int skcipher_accept_parent(void *private, struct sock *sk) +{ + struct crypto_skcipher *tfm = private; + + if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) + return -ENOKEY; + + return skcipher_accept_parent_nokey(private, sk); +} + +static const struct af_alg_type algif_type_skcipher = { + .bind = skcipher_bind, + .release = skcipher_release, + .setkey = skcipher_setkey, + .accept = skcipher_accept_parent, + .accept_nokey = skcipher_accept_parent_nokey, + .ops = &algif_skcipher_ops, + .ops_nokey = &algif_skcipher_ops_nokey, + .name = "skcipher", + .owner = THIS_MODULE +}; + +static int __init algif_skcipher_init(void) +{ + return af_alg_register_type(&algif_type_skcipher); +} + +static void __exit algif_skcipher_exit(void) +{ + int err = af_alg_unregister_type(&algif_type_skcipher); + BUG_ON(err); +} + +module_init(algif_skcipher_init); +module_exit(algif_skcipher_exit); +MODULE_LICENSE("GPL"); -- cgit v1.2.3