--- /dev/null
+/*
+ * 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 <asm/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>
+
+struct alg_type_list {
+ const struct af_alg_type *type;
+ struct list_head list;
+};
+
+static atomic_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);
+
+ 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;
+
+ 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);
--- /dev/null
+/*
+ * if_alg: User-space algorithm interface
+ *
+ * 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.
+ *
+ */
+
+#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/types.h>
+#include <net/sock.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;
+
+ const struct af_alg_type *type;
+ void *private;
+};
+
+struct af_alg_completion {
+ struct completion completion;
+ int err;
+};
+
+struct af_alg_control {
+ struct af_alg_iv *iv;
+ int op;
+};
+
+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);
+
+ struct proto_ops *ops;
+ struct module *owner;
+ char name[14];
+};
+
+struct af_alg_sgl {
+ struct scatterlist sg[ALG_MAX_PAGES];
+ struct page *pages[ALG_MAX_PAGES];
+};
+
+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);
+int af_alg_accept(struct sock *sk, struct socket *newsock);
+
+int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len,
+ int write);
+void af_alg_free_sg(struct af_alg_sgl *sgl);
+
+int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con);
+
+int af_alg_wait_for_completion(int err, struct af_alg_completion *completion);
+void af_alg_complete(struct crypto_async_request *req, int err);
+
+static inline struct alg_sock *alg_sk(struct sock *sk)
+{
+ return (struct alg_sock *)sk;
+}
+
+static inline void af_alg_release_parent(struct sock *sk)
+{
+ sock_put(alg_sk(sk)->parent);
+}
+
+static inline void af_alg_init_completion(struct af_alg_completion *completion)
+{
+ init_completion(&completion->completion);
+}
+
+#endif /* _CRYPTO_IF_ALG_H */