| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * if_alg: User-space algorithm interface |
| * |
| * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au> |
| */ |
| |
| #ifndef _CRYPTO_IF_ALG_H |
| #define _CRYPTO_IF_ALG_H |
| |
| #include <linux/compiler.h> |
| #include <linux/completion.h> |
| #include <linux/if_alg.h> |
| #include <linux/scatterlist.h> |
| #include <linux/types.h> |
| #include <linux/atomic.h> |
| #include <net/sock.h> |
| |
| #include <crypto/aead.h> |
| #include <crypto/skcipher.h> |
| |
| #define ALG_MAX_PAGES 16 |
| |
| struct crypto_async_request; |
| |
| struct alg_sock { |
| /* struct sock must be the first member of struct alg_sock */ |
| struct sock sk; |
| |
| struct sock *parent; |
| |
| atomic_t refcnt; |
| atomic_t nokey_refcnt; |
| |
| const struct af_alg_type *type; |
| void *private; |
| }; |
| |
| struct af_alg_control { |
| struct af_alg_iv *iv; |
| int op; |
| unsigned int aead_assoclen; |
| }; |
| |
| struct af_alg_type { |
| void *(*bind)(const char *name, u32 type, u32 mask); |
| void (*release)(void *private); |
| int (*setkey)(void *private, const u8 *key, unsigned int keylen); |
| int (*accept)(void *private, struct sock *sk); |
| int (*accept_nokey)(void *private, struct sock *sk); |
| int (*setauthsize)(void *private, unsigned int authsize); |
| |
| struct proto_ops *ops; |
| struct proto_ops *ops_nokey; |
| struct module *owner; |
| char name[14]; |
| }; |
| |
| struct af_alg_sgl { |
| struct scatterlist sg[ALG_MAX_PAGES + 1]; |
| struct page *pages[ALG_MAX_PAGES]; |
| unsigned int npages; |
| }; |
| |
| /* TX SGL entry */ |
| struct af_alg_tsgl { |
| struct list_head list; |
| unsigned int cur; /* Last processed SG entry */ |
| struct scatterlist sg[0]; /* Array of SGs forming the SGL */ |
| }; |
| |
| #define MAX_SGL_ENTS ((4096 - sizeof(struct af_alg_tsgl)) / \ |
| sizeof(struct scatterlist) - 1) |
| |
| /* RX SGL entry */ |
| struct af_alg_rsgl { |
| struct af_alg_sgl sgl; |
| struct list_head list; |
| size_t sg_num_bytes; /* Bytes of data in that SGL */ |
| }; |
| |
| /** |
| * struct af_alg_async_req - definition of crypto request |
| * @iocb: IOCB for AIO operations |
| * @sk: Socket the request is associated with |
| * @first_rsgl: First RX SG |
| * @last_rsgl: Pointer to last RX SG |
| * @rsgl_list: Track RX SGs |
| * @tsgl: Private, per request TX SGL of buffers to process |
| * @tsgl_entries: Number of entries in priv. TX SGL |
| * @outlen: Number of output bytes generated by crypto op |
| * @areqlen: Length of this data structure |
| * @cra_u: Cipher request |
| */ |
| struct af_alg_async_req { |
| struct kiocb *iocb; |
| struct sock *sk; |
| |
| struct af_alg_rsgl first_rsgl; |
| struct af_alg_rsgl *last_rsgl; |
| struct list_head rsgl_list; |
| |
| struct scatterlist *tsgl; |
| unsigned int tsgl_entries; |
| |
| unsigned int outlen; |
| unsigned int areqlen; |
| |
| union { |
| struct aead_request aead_req; |
| struct skcipher_request skcipher_req; |
| } cra_u; |
| |
| /* req ctx trails this struct */ |
| }; |
| |
| /** |
| * struct af_alg_ctx - definition of the crypto context |
| * |
| * The crypto context tracks the input data during the lifetime of an AF_ALG |
| * socket. |
| * |
| * @tsgl_list: Link to TX SGL |
| * @iv: IV for cipher operation |
| * @aead_assoclen: Length of AAD for AEAD cipher operations |
| * @completion: Work queue for synchronous operation |
| * @used: TX bytes sent to kernel. This variable is used to |
| * ensure that user space cannot cause the kernel |
| * to allocate too much memory in sendmsg operation. |
| * @rcvused: Total RX bytes to be filled by kernel. This variable |
| * is used to ensure user space cannot cause the kernel |
| * to allocate too much memory in a recvmsg operation. |
| * @more: More data to be expected from user space? |
| * @merge: Shall new data from user space be merged into existing |
| * SG? |
| * @enc: Cryptographic operation to be performed when |
| * recvmsg is invoked. |
| * @init: True if metadata has been sent. |
| * @len: Length of memory allocated for this data structure. |
| */ |
| struct af_alg_ctx { |
| struct list_head tsgl_list; |
| |
| void *iv; |
| size_t aead_assoclen; |
| |
| struct crypto_wait wait; |
| |
| size_t used; |
| atomic_t rcvused; |
| |
| bool more; |
| bool merge; |
| bool enc; |
| bool init; |
| |
| unsigned int len; |
| }; |
| |
| int af_alg_register_type(const struct af_alg_type *type); |
| int af_alg_unregister_type(const struct af_alg_type *type); |
| |
| int af_alg_release(struct socket *sock); |
| void af_alg_release_parent(struct sock *sk); |
| int af_alg_accept(struct sock *sk, struct socket *newsock, bool kern); |
| |
| int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len); |
| void af_alg_free_sg(struct af_alg_sgl *sgl); |
| |
| static inline struct alg_sock *alg_sk(struct sock *sk) |
| { |
| return (struct alg_sock *)sk; |
| } |
| |
| /** |
| * Size of available buffer for sending data from user space to kernel. |
| * |
| * @sk socket of connection to user space |
| * @return number of bytes still available |
| */ |
| static inline int af_alg_sndbuf(struct sock *sk) |
| { |
| struct alg_sock *ask = alg_sk(sk); |
| struct af_alg_ctx *ctx = ask->private; |
| |
| return max_t(int, max_t(int, sk->sk_sndbuf & PAGE_MASK, PAGE_SIZE) - |
| ctx->used, 0); |
| } |
| |
| /** |
| * Can the send buffer still be written to? |
| * |
| * @sk socket of connection to user space |
| * @return true => writable, false => not writable |
| */ |
| static inline bool af_alg_writable(struct sock *sk) |
| { |
| return PAGE_SIZE <= af_alg_sndbuf(sk); |
| } |
| |
| /** |
| * Size of available buffer used by kernel for the RX user space operation. |
| * |
| * @sk socket of connection to user space |
| * @return number of bytes still available |
| */ |
| static inline int af_alg_rcvbuf(struct sock *sk) |
| { |
| struct alg_sock *ask = alg_sk(sk); |
| struct af_alg_ctx *ctx = ask->private; |
| |
| return max_t(int, max_t(int, sk->sk_rcvbuf & PAGE_MASK, PAGE_SIZE) - |
| atomic_read(&ctx->rcvused), 0); |
| } |
| |
| /** |
| * Can the RX buffer still be written to? |
| * |
| * @sk socket of connection to user space |
| * @return true => writable, false => not writable |
| */ |
| static inline bool af_alg_readable(struct sock *sk) |
| { |
| return PAGE_SIZE <= af_alg_rcvbuf(sk); |
| } |
| |
| unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset); |
| void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst, |
| size_t dst_offset); |
| void af_alg_wmem_wakeup(struct sock *sk); |
| int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min); |
| int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size, |
| unsigned int ivsize); |
| ssize_t af_alg_sendpage(struct socket *sock, struct page *page, |
| int offset, size_t size, int flags); |
| void af_alg_free_resources(struct af_alg_async_req *areq); |
| void af_alg_async_cb(struct crypto_async_request *_req, int err); |
| __poll_t af_alg_poll(struct file *file, struct socket *sock, |
| poll_table *wait); |
| struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk, |
| unsigned int areqlen); |
| int af_alg_get_rsgl(struct sock *sk, struct msghdr *msg, int flags, |
| struct af_alg_async_req *areq, size_t maxsize, |
| size_t *outlen); |
| |
| #endif /* _CRYPTO_IF_ALG_H */ |