| /* |
| * af_alg: User-space algorithm interface |
| * |
| * This file provides the user-space API for algorithms. |
| * |
| * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au> |
| * |
| * 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. |
| * |
| */ |
| |
| #include <linux/atomic.h> |
| #include <crypto/if_alg.h> |
| #include <linux/crypto.h> |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/list.h> |
| #include <linux/module.h> |
| #include <linux/net.h> |
| #include <linux/rwsem.h> |
| #include <linux/security.h> |
| |
| struct alg_type_list { |
| const struct af_alg_type *type; |
| struct list_head list; |
| }; |
| |
| static atomic_long_t alg_memory_allocated; |
| |
| static struct proto alg_proto = { |
| .name = "ALG", |
| .owner = THIS_MODULE, |
| .memory_allocated = &alg_memory_allocated, |
| .obj_size = sizeof(struct alg_sock), |
| }; |
| |
| static LIST_HEAD(alg_types); |
| static DECLARE_RWSEM(alg_types_sem); |
| |
| static const struct af_alg_type *alg_get_type(const char *name) |
| { |
| const struct af_alg_type *type = ERR_PTR(-ENOENT); |
| struct alg_type_list *node; |
| |
| down_read(&alg_types_sem); |
| list_for_each_entry(node, &alg_types, list) { |
| if (strcmp(node->type->name, name)) |
| continue; |
| |
| if (try_module_get(node->type->owner)) |
| type = node->type; |
| break; |
| } |
| up_read(&alg_types_sem); |
| |
| return type; |
| } |
| |
| int af_alg_register_type(const struct af_alg_type *type) |
| { |
| struct alg_type_list *node; |
| int err = -EEXIST; |
| |
| down_write(&alg_types_sem); |
| list_for_each_entry(node, &alg_types, list) { |
| if (!strcmp(node->type->name, type->name)) |
| goto unlock; |
| } |
| |
| node = kmalloc(sizeof(*node), GFP_KERNEL); |
| err = -ENOMEM; |
| if (!node) |
| goto unlock; |
| |
| type->ops->owner = THIS_MODULE; |
| node->type = type; |
| list_add(&node->list, &alg_types); |
| err = 0; |
| |
| unlock: |
| up_write(&alg_types_sem); |
| |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(af_alg_register_type); |
| |
| int af_alg_unregister_type(const struct af_alg_type *type) |
| { |
| struct alg_type_list *node; |
| int err = -ENOENT; |
| |
| down_write(&alg_types_sem); |
| list_for_each_entry(node, &alg_types, list) { |
| if (strcmp(node->type->name, type->name)) |
| continue; |
| |
| list_del(&node->list); |
| kfree(node); |
| err = 0; |
| break; |
| } |
| up_write(&alg_types_sem); |
| |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(af_alg_unregister_type); |
| |
| static void alg_do_release(const struct af_alg_type *type, void *private) |
| { |
| if (!type) |
| return; |
| |
| type->release(private); |
| module_put(type->owner); |
| } |
| |
| int af_alg_release(struct socket *sock) |
| { |
| if (sock->sk) |
| sock_put(sock->sk); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(af_alg_release); |
| |
| static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) |
| { |
| struct sock *sk = sock->sk; |
| struct alg_sock *ask = alg_sk(sk); |
| struct sockaddr_alg *sa = (void *)uaddr; |
| const struct af_alg_type *type; |
| void *private; |
| |
| if (sock->state == SS_CONNECTED) |
| return -EINVAL; |
| |
| if (addr_len != sizeof(*sa)) |
| return -EINVAL; |
| |
| sa->salg_type[sizeof(sa->salg_type) - 1] = 0; |
| sa->salg_name[sizeof(sa->salg_name) - 1] = 0; |
| |
| type = alg_get_type(sa->salg_type); |
| if (IS_ERR(type) && PTR_ERR(type) == -ENOENT) { |
| request_module("algif-%s", sa->salg_type); |
| type = alg_get_type(sa->salg_type); |
| } |
| |
| if (IS_ERR(type)) |
| return PTR_ERR(type); |
| |
| private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask); |
| if (IS_ERR(private)) { |
| module_put(type->owner); |
| return PTR_ERR(private); |
| } |
| |
| lock_sock(sk); |
| |
| swap(ask->type, type); |
| swap(ask->private, private); |
| |
| release_sock(sk); |
| |
| alg_do_release(type, private); |
| |
| return 0; |
| } |
| |
| static int alg_setkey(struct sock *sk, char __user *ukey, |
| unsigned int keylen) |
| { |
| struct alg_sock *ask = alg_sk(sk); |
| const struct af_alg_type *type = ask->type; |
| u8 *key; |
| int err; |
| |
| key = sock_kmalloc(sk, keylen, GFP_KERNEL); |
| if (!key) |
| return -ENOMEM; |
| |
| err = -EFAULT; |
| if (copy_from_user(key, ukey, keylen)) |
| goto out; |
| |
| err = type->setkey(ask->private, key, keylen); |
| |
| out: |
| sock_kfree_s(sk, key, keylen); |
| |
| return err; |
| } |
| |
| static int alg_setsockopt(struct socket *sock, int level, int optname, |
| char __user *optval, unsigned int optlen) |
| { |
| struct sock *sk = sock->sk; |
| struct alg_sock *ask = alg_sk(sk); |
| const struct af_alg_type *type; |
| int err = -ENOPROTOOPT; |
| |
| lock_sock(sk); |
| type = ask->type; |
| |
| if (level != SOL_ALG || !type) |
| goto unlock; |
| |
| switch (optname) { |
| case ALG_SET_KEY: |
| if (sock->state == SS_CONNECTED) |
| goto unlock; |
| if (!type->setkey) |
| goto unlock; |
| |
| err = alg_setkey(sk, optval, optlen); |
| } |
| |
| unlock: |
| release_sock(sk); |
| |
| return err; |
| } |
| |
| int af_alg_accept(struct sock *sk, struct socket *newsock) |
| { |
| struct alg_sock *ask = alg_sk(sk); |
| const struct af_alg_type *type; |
| struct sock *sk2; |
| int err; |
| |
| lock_sock(sk); |
| type = ask->type; |
| |
| err = -EINVAL; |
| if (!type) |
| goto unlock; |
| |
| sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto); |
| err = -ENOMEM; |
| if (!sk2) |
| goto unlock; |
| |
| sock_init_data(newsock, sk2); |
| sock_graft(sk2, newsock); |
| security_sk_clone(sk, sk2); |
| |
| err = type->accept(ask->private, sk2); |
| if (err) { |
| sk_free(sk2); |
| goto unlock; |
| } |
| |
| sk2->sk_family = PF_ALG; |
| |
| sock_hold(sk); |
| alg_sk(sk2)->parent = sk; |
| alg_sk(sk2)->type = type; |
| |
| newsock->ops = type->ops; |
| newsock->state = SS_CONNECTED; |
| |
| err = 0; |
| |
| unlock: |
| release_sock(sk); |
| |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(af_alg_accept); |
| |
| static int alg_accept(struct socket *sock, struct socket *newsock, int flags) |
| { |
| return af_alg_accept(sock->sk, newsock); |
| } |
| |
| static const struct proto_ops alg_proto_ops = { |
| .family = PF_ALG, |
| .owner = THIS_MODULE, |
| |
| .connect = sock_no_connect, |
| .socketpair = sock_no_socketpair, |
| .getname = sock_no_getname, |
| .ioctl = sock_no_ioctl, |
| .listen = sock_no_listen, |
| .shutdown = sock_no_shutdown, |
| .getsockopt = sock_no_getsockopt, |
| .mmap = sock_no_mmap, |
| .sendpage = sock_no_sendpage, |
| .sendmsg = sock_no_sendmsg, |
| .recvmsg = sock_no_recvmsg, |
| .poll = sock_no_poll, |
| |
| .bind = alg_bind, |
| .release = af_alg_release, |
| .setsockopt = alg_setsockopt, |
| .accept = alg_accept, |
| }; |
| |
| static void alg_sock_destruct(struct sock *sk) |
| { |
| struct alg_sock *ask = alg_sk(sk); |
| |
| alg_do_release(ask->type, ask->private); |
| } |
| |
| static int alg_create(struct net *net, struct socket *sock, int protocol, |
| int kern) |
| { |
| struct sock *sk; |
| int err; |
| |
| if (sock->type != SOCK_SEQPACKET) |
| return -ESOCKTNOSUPPORT; |
| if (protocol != 0) |
| return -EPROTONOSUPPORT; |
| |
| err = -ENOMEM; |
| sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto); |
| if (!sk) |
| goto out; |
| |
| sock->ops = &alg_proto_ops; |
| sock_init_data(sock, sk); |
| |
| sk->sk_family = PF_ALG; |
| sk->sk_destruct = alg_sock_destruct; |
| |
| return 0; |
| out: |
| return err; |
| } |
| |
| static const struct net_proto_family alg_family = { |
| .family = PF_ALG, |
| .create = alg_create, |
| .owner = THIS_MODULE, |
| }; |
| |
| int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len, |
| int write) |
| { |
| unsigned long from = (unsigned long)addr; |
| unsigned long npages; |
| unsigned off; |
| int err; |
| int i; |
| |
| err = -EFAULT; |
| if (!access_ok(write ? VERIFY_READ : VERIFY_WRITE, addr, len)) |
| goto out; |
| |
| off = from & ~PAGE_MASK; |
| npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| if (npages > ALG_MAX_PAGES) |
| npages = ALG_MAX_PAGES; |
| |
| err = get_user_pages_fast(from, npages, write, sgl->pages); |
| if (err < 0) |
| goto out; |
| |
| npages = err; |
| err = -EINVAL; |
| if (WARN_ON(npages == 0)) |
| goto out; |
| |
| err = 0; |
| |
| sg_init_table(sgl->sg, npages); |
| |
| for (i = 0; i < npages; i++) { |
| int plen = min_t(int, len, PAGE_SIZE - off); |
| |
| sg_set_page(sgl->sg + i, sgl->pages[i], plen, off); |
| |
| off = 0; |
| len -= plen; |
| err += plen; |
| } |
| |
| out: |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(af_alg_make_sg); |
| |
| void af_alg_free_sg(struct af_alg_sgl *sgl) |
| { |
| int i; |
| |
| i = 0; |
| do { |
| put_page(sgl->pages[i]); |
| } while (!sg_is_last(sgl->sg + (i++))); |
| } |
| EXPORT_SYMBOL_GPL(af_alg_free_sg); |
| |
| int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con) |
| { |
| struct cmsghdr *cmsg; |
| |
| for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { |
| if (!CMSG_OK(msg, cmsg)) |
| return -EINVAL; |
| if (cmsg->cmsg_level != SOL_ALG) |
| continue; |
| |
| switch(cmsg->cmsg_type) { |
| case ALG_SET_IV: |
| if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv))) |
| return -EINVAL; |
| con->iv = (void *)CMSG_DATA(cmsg); |
| if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen + |
| sizeof(*con->iv))) |
| return -EINVAL; |
| break; |
| |
| case ALG_SET_OP: |
| if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32))) |
| return -EINVAL; |
| con->op = *(u32 *)CMSG_DATA(cmsg); |
| break; |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(af_alg_cmsg_send); |
| |
| int af_alg_wait_for_completion(int err, struct af_alg_completion *completion) |
| { |
| switch (err) { |
| case -EINPROGRESS: |
| case -EBUSY: |
| wait_for_completion(&completion->completion); |
| INIT_COMPLETION(completion->completion); |
| err = completion->err; |
| break; |
| }; |
| |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(af_alg_wait_for_completion); |
| |
| void af_alg_complete(struct crypto_async_request *req, int err) |
| { |
| struct af_alg_completion *completion = req->data; |
| |
| if (err == -EINPROGRESS) |
| return; |
| |
| completion->err = err; |
| complete(&completion->completion); |
| } |
| EXPORT_SYMBOL_GPL(af_alg_complete); |
| |
| static int __init af_alg_init(void) |
| { |
| int err = proto_register(&alg_proto, 0); |
| |
| if (err) |
| goto out; |
| |
| err = sock_register(&alg_family); |
| if (err != 0) |
| goto out_unregister_proto; |
| |
| out: |
| return err; |
| |
| out_unregister_proto: |
| proto_unregister(&alg_proto); |
| goto out; |
| } |
| |
| static void __exit af_alg_exit(void) |
| { |
| sock_unregister(PF_ALG); |
| proto_unregister(&alg_proto); |
| } |
| |
| module_init(af_alg_init); |
| module_exit(af_alg_exit); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS_NETPROTO(AF_ALG); |