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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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#include <linux/atomic.h>#include <linux/capability.h>#include <crypto/if_alg.h>#include <linux/crypto.h>#include <linux/init.h>#include <linux/kernel.h>#include <linux/key.h>#include <linux/key-type.h>#include <linux/list.h>#include <linux/module.h>#include <linux/net.h>#include <linux/rwsem.h>#include <linux/sched.h>#include <linux/sched/signal.h>#include <linux/security.h>#include <linux/string.h>#include <linux/sysctl.h>#include <linux/user_namespace.h>#include <keys/user-type.h>#include <keys/trusted-type.h>#include <keys/encrypted-type.h>
static int af_alg_restrict = 1;
static const struct ctl_table af_alg_table[] = { { .procname = "af_alg_restrict", .data = &af_alg_restrict, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_TWO, },};
static struct ctl_table_header *af_alg_header;
struct alg_type_list { const struct af_alg_type *type; struct list_head list;};
static struct proto alg_proto = { .name = "ALG", .owner = THIS_MODULE, .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_obj(*node); err = -ENOMEM; if (!node) goto unlock;
type->ops->owner = THIS_MODULE; if (type->ops_nokey) type->ops_nokey->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 bool af_alg_capable(void){ return ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN) || capable(CAP_SYS_ADMIN);}
int af_alg_check_restriction(const char *name, const struct af_alg_allowlist_entry allowlist[]){ int level = READ_ONCE(af_alg_restrict);
if (level == 0) return 0; if (level == 1) { for (const struct af_alg_allowlist_entry *ent = allowlist; ent->name; ent++) { if (strcmp(name, ent->name) == 0) { if ((ent->flags & AF_ALG_UNPRIVILEGED) || af_alg_capable()) return 0; /* List contains at most one entry per name. */ break; } } } /* * Use -ENOENT (the error code for "algorithm not found") instead of * -EACCES or -EPERM, for the highest chance of correctly triggering * fallback code paths in userspace programs. * * Don't log a warning, since it would be noisy. iwd tries to bind a * bunch of algorithms that it never uses. */ return -ENOENT;}EXPORT_SYMBOL_GPL(af_alg_check_restriction);
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); sock->sk = NULL; } return 0;}EXPORT_SYMBOL_GPL(af_alg_release);
void af_alg_release_parent(struct sock *sk){ struct alg_sock *ask = alg_sk(sk); unsigned int nokey = atomic_read(&ask->nokey_refcnt);
sk = ask->parent; ask = alg_sk(sk);
if (nokey) atomic_dec(&ask->nokey_refcnt);
if (atomic_dec_and_test(&ask->refcnt)) sock_put(sk);}EXPORT_SYMBOL_GPL(af_alg_release_parent);
static int alg_bind(struct socket *sock, struct sockaddr_unsized *uaddr, int addr_len){ const u32 allowed = CRYPTO_ALG_KERN_DRIVER_ONLY; struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); struct sockaddr_alg_new *sa = (void *)uaddr; const struct af_alg_type *type; void *private; int err;
if (sock->state == SS_CONNECTED) return -EINVAL;
BUILD_BUG_ON(offsetof(struct sockaddr_alg_new, salg_name) != offsetof(struct sockaddr_alg, salg_name)); BUILD_BUG_ON(offsetof(struct sockaddr_alg, salg_name) != sizeof(*sa));
if (addr_len < sizeof(*sa) + 1) return -EINVAL;
/* If caller uses non-allowed flag, return error. */ if ((sa->salg_feat & ~allowed) || (sa->salg_mask & ~allowed)) return -EINVAL;
sa->salg_type[sizeof(sa->salg_type) - 1] = 0; sa->salg_name[addr_len - sizeof(*sa) - 1] = 0;
type = alg_get_type(sa->salg_type); if (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); if (IS_ERR(private)) { module_put(type->owner); return PTR_ERR(private); }
err = -EBUSY; lock_sock(sk); if (atomic_read(&ask->refcnt)) goto unlock;
swap(ask->type, type); swap(ask->private, private);
err = 0;
unlock: release_sock(sk);
alg_do_release(type, private);
return err;}
static int alg_setkey(struct sock *sk, sockptr_t 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_sockptr(key, ukey, keylen)) goto out;
err = type->setkey(ask->private, key, keylen);
out: sock_kzfree_s(sk, key, keylen);
return err;}
#ifdef CONFIG_KEYS
static const u8 *key_data_ptr_user(const struct key *key, unsigned int *datalen){ const struct user_key_payload *ukp;
ukp = user_key_payload_locked(key); if (IS_ERR_OR_NULL(ukp)) return ERR_PTR(-EKEYREVOKED);
*datalen = key->datalen;
return ukp->data;}
static const u8 *key_data_ptr_encrypted(const struct key *key, unsigned int *datalen){ const struct encrypted_key_payload *ekp;
ekp = dereference_key_locked(key); if (IS_ERR_OR_NULL(ekp)) return ERR_PTR(-EKEYREVOKED);
*datalen = ekp->decrypted_datalen;
return ekp->decrypted_data;}
static const u8 *key_data_ptr_trusted(const struct key *key, unsigned int *datalen){ const struct trusted_key_payload *tkp;
tkp = dereference_key_locked(key); if (IS_ERR_OR_NULL(tkp)) return ERR_PTR(-EKEYREVOKED);
*datalen = tkp->key_len;
return tkp->key;}
static struct key *lookup_key(key_serial_t serial){ key_ref_t key_ref;
key_ref = lookup_user_key(serial, 0, KEY_NEED_SEARCH); if (IS_ERR(key_ref)) return ERR_CAST(key_ref);
return key_ref_to_ptr(key_ref);}
static int alg_setkey_by_key_serial(struct alg_sock *ask, sockptr_t optval, unsigned int optlen){ const struct af_alg_type *type = ask->type; u8 *key_data = NULL; unsigned int key_datalen; key_serial_t serial; struct key *key; const u8 *ret; int err;
if (optlen != sizeof(serial)) return -EINVAL;
if (copy_from_sockptr(&serial, optval, optlen)) return -EFAULT;
key = lookup_key(serial); if (IS_ERR(key)) return PTR_ERR(key);
down_read(&key->sem);
ret = ERR_PTR(-ENOPROTOOPT); if (!strcmp(key->type->name, "user") || !strcmp(key->type->name, "logon")) { ret = key_data_ptr_user(key, &key_datalen); } else if (IS_REACHABLE(CONFIG_ENCRYPTED_KEYS) && !strcmp(key->type->name, "encrypted")) { ret = key_data_ptr_encrypted(key, &key_datalen); } else if (IS_REACHABLE(CONFIG_TRUSTED_KEYS) && !strcmp(key->type->name, "trusted")) { ret = key_data_ptr_trusted(key, &key_datalen); }
if (IS_ERR(ret)) { up_read(&key->sem); key_put(key); return PTR_ERR(ret); }
key_data = sock_kmemdup(&ask->sk, ret, key_datalen, GFP_KERNEL); if (!key_data) { up_read(&key->sem); key_put(key); return -ENOMEM; }
up_read(&key->sem); key_put(key);
err = type->setkey(ask->private, key_data, key_datalen);
sock_kzfree_s(&ask->sk, key_data, key_datalen);
return err;}
#else
static inline int alg_setkey_by_key_serial(struct alg_sock *ask, sockptr_t optval, unsigned int optlen){ return -ENOPROTOOPT;}
#endif
static int alg_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval, unsigned int optlen){ struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); const struct af_alg_type *type; int err = -EBUSY;
lock_sock(sk); if (atomic_read(&ask->refcnt) != atomic_read(&ask->nokey_refcnt)) goto unlock;
type = ask->type;
err = -ENOPROTOOPT; if (level != SOL_ALG || !type) goto unlock;
switch (optname) { case ALG_SET_KEY: case ALG_SET_KEY_BY_KEY_SERIAL: if (sock->state == SS_CONNECTED) goto unlock; if (!type->setkey) goto unlock;
if (optname == ALG_SET_KEY_BY_KEY_SERIAL) err = alg_setkey_by_key_serial(ask, optval, optlen); else err = alg_setkey(sk, optval, optlen); break; case ALG_SET_AEAD_AUTHSIZE: if (sock->state == SS_CONNECTED) goto unlock; if (!type->setauthsize) goto unlock; err = type->setauthsize(ask->private, optlen); break; case ALG_SET_DRBG_ENTROPY: if (sock->state == SS_CONNECTED) goto unlock; if (!type->setentropy) goto unlock;
err = type->setentropy(ask->private, optval, optlen); }
unlock: release_sock(sk);
return err;}
int af_alg_accept(struct sock *sk, struct socket *newsock, struct proto_accept_arg *arg){ struct alg_sock *ask = alg_sk(sk); const struct af_alg_type *type; struct sock *sk2; unsigned int nokey; 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, arg->kern); err = -ENOMEM; if (!sk2) goto unlock;
sock_init_data(newsock, sk2); security_sock_graft(sk2, newsock); security_sk_clone(sk, sk2);
/* * newsock->ops assigned here to allow type->accept call to override * them when required. */ newsock->ops = type->ops; err = type->accept(ask->private, sk2);
nokey = err == -ENOKEY; if (nokey && type->accept_nokey) err = type->accept_nokey(ask->private, sk2);
if (err) goto unlock;
if (atomic_inc_return_relaxed(&ask->refcnt) == 1) sock_hold(sk); if (nokey) { atomic_inc(&ask->nokey_refcnt); atomic_set(&alg_sk(sk2)->nokey_refcnt, 1); } alg_sk(sk2)->parent = sk; alg_sk(sk2)->type = type;
newsock->state = SS_CONNECTED;
if (nokey) newsock->ops = type->ops_nokey;
err = 0;
unlock: release_sock(sk);
return err;}EXPORT_SYMBOL_GPL(af_alg_accept);
static int alg_accept(struct socket *sock, struct socket *newsock, struct proto_accept_arg *arg){ return af_alg_accept(sock->sk, newsock, arg);}
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, .mmap = sock_no_mmap, .sendmsg = sock_no_sendmsg, .recvmsg = sock_no_recvmsg,
.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 (READ_ONCE(af_alg_restrict) == 2) return -EAFNOSUPPORT;
if (sock->type != SOCK_SEQPACKET) return -ESOCKTNOSUPPORT; if (protocol != 0) return -EPROTONOSUPPORT;
err = -ENOMEM; sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto, kern); if (!sk) goto out;
sock->ops = &alg_proto_ops; sock_init_data(sock, sk);
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,};
static void af_alg_link_sg(struct af_alg_sgl *sgl_prev, struct af_alg_sgl *sgl_new){ sg_unmark_end(sgl_prev->sgt.sgl + sgl_prev->sgt.nents - 1); sg_chain(sgl_prev->sgt.sgl, sgl_prev->sgt.nents + 1, sgl_new->sgt.sgl);}
void af_alg_free_sg(struct af_alg_sgl *sgl){ int i;
if (sgl->sgt.sgl) { if (sgl->need_unpin) for (i = 0; i < sgl->sgt.nents; i++) unpin_user_page(sg_page(&sgl->sgt.sgl[i])); if (sgl->sgt.sgl != sgl->sgl) kvfree(sgl->sgt.sgl); sgl->sgt.sgl = NULL; }}EXPORT_SYMBOL_GPL(af_alg_free_sg);
static int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con){ struct cmsghdr *cmsg;
for_each_cmsghdr(cmsg, msg) { 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;
case ALG_SET_AEAD_ASSOCLEN: if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32))) return -EINVAL; con->aead_assoclen = *(u32 *)CMSG_DATA(cmsg); if (con->aead_assoclen >= 0x80000000u) return -EINVAL; break;
default: return -EINVAL; } }
return 0;}
/** * af_alg_alloc_tsgl - allocate the TX SGL * * @sk: socket of connection to user space * Return: 0 upon success, < 0 upon error */static int af_alg_alloc_tsgl(struct sock *sk){ struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; struct af_alg_tsgl *sgl; struct scatterlist *sg = NULL;
sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list); if (!list_empty(&ctx->tsgl_list)) sg = sgl->sg;
if (!sg || sgl->cur >= MAX_SGL_ENTS) { sgl = sock_kmalloc(sk, struct_size(sgl, sg, (MAX_SGL_ENTS + 1)), GFP_KERNEL); if (!sgl) return -ENOMEM;
sg_init_table(sgl->sg, MAX_SGL_ENTS + 1); sgl->cur = 0;
if (sg) { sg_unmark_end(sg + MAX_SGL_ENTS - 1); sg_chain(sg, MAX_SGL_ENTS + 1, sgl->sg); }
list_add_tail(&sgl->list, &ctx->tsgl_list); }
return 0;}
/** * af_alg_count_tsgl - Count number of TX SG entries * * The counting starts from the beginning of the SGL to @bytes. * * @sk: socket of connection to user space * @bytes: Count the number of SG entries holding given number of bytes. * Return: Number of TX SG entries found given the constraints */unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes){ const struct alg_sock *ask = alg_sk(sk); const struct af_alg_ctx *ctx = ask->private; const struct af_alg_tsgl *sgl; unsigned int i; unsigned int sgl_count = 0;
if (!bytes) return 0;
list_for_each_entry(sgl, &ctx->tsgl_list, list) { const struct scatterlist *sg = sgl->sg;
for (i = 0; i < sgl->cur; i++) { sgl_count++; if (sg[i].length >= bytes) return sgl_count;
bytes -= sg[i].length; } }
return sgl_count;}EXPORT_SYMBOL_GPL(af_alg_count_tsgl);
/** * af_alg_pull_tsgl - Release the specified buffers from TX SGL * * If @dst is non-null, reassign the pages to @dst. The caller must release * the pages. * * @sk: socket of connection to user space * @used: Number of bytes to pull from TX SGL * @dst: If non-NULL, buffer is reassigned to dst SGL instead of releasing. The * caller must release the buffers in dst. */void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst){ struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; struct af_alg_tsgl *sgl; struct scatterlist *sg; unsigned int i, j = 0;
while (!list_empty(&ctx->tsgl_list)) { sgl = list_first_entry(&ctx->tsgl_list, struct af_alg_tsgl, list); sg = sgl->sg;
for (i = 0; i < sgl->cur; i++) { size_t plen = min_t(size_t, used, sg[i].length); struct page *page = sg_page(sg + i);
if (!page) continue;
/* * Assumption: caller created af_alg_count_tsgl(len) * SG entries in dst. */ if (dst && plen) { /* reassign page to dst */ get_page(page); sg_set_page(dst + j, page, plen, sg[i].offset); j++; }
sg[i].length -= plen; sg[i].offset += plen;
used -= plen; ctx->used -= plen;
if (sg[i].length) return;
put_page(page); sg_assign_page(sg + i, NULL); }
list_del(&sgl->list); sock_kfree_s(sk, sgl, struct_size(sgl, sg, MAX_SGL_ENTS + 1)); }
if (!ctx->used) ctx->merge = 0; ctx->init = ctx->more;}EXPORT_SYMBOL_GPL(af_alg_pull_tsgl);
/** * af_alg_free_areq_sgls - Release TX and RX SGLs of the request * * @areq: Request holding the TX and RX SGL */static void af_alg_free_areq_sgls(struct af_alg_async_req *areq){ struct sock *sk = areq->sk; struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; struct af_alg_rsgl *rsgl, *tmp; struct scatterlist *tsgl; struct scatterlist *sg; unsigned int i;
list_for_each_entry_safe(rsgl, tmp, &areq->rsgl_list, list) { atomic_sub(rsgl->sg_num_bytes, &ctx->rcvused); af_alg_free_sg(&rsgl->sgl); list_del(&rsgl->list); if (rsgl != &areq->first_rsgl) sock_kfree_s(sk, rsgl, sizeof(*rsgl)); }
tsgl = areq->tsgl; if (tsgl) { for_each_sg(tsgl, sg, areq->tsgl_entries, i) { if (!sg_page(sg)) continue; put_page(sg_page(sg)); }
sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl)); }}
/** * af_alg_wait_for_wmem - wait for availability of writable memory * * @sk: socket of connection to user space * @flags: If MSG_DONTWAIT is set, then only report if function would sleep * Return: 0 when writable memory is available, < 0 upon error */static int af_alg_wait_for_wmem(struct sock *sk, unsigned int flags){ DEFINE_WAIT_FUNC(wait, woken_wake_function); int err = -ERESTARTSYS; long timeout;
if (flags & MSG_DONTWAIT) return -EAGAIN;
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
add_wait_queue(sk_sleep(sk), &wait); for (;;) { if (signal_pending(current)) break; timeout = MAX_SCHEDULE_TIMEOUT; if (sk_wait_event(sk, &timeout, af_alg_writable(sk), &wait)) { err = 0; break; } } remove_wait_queue(sk_sleep(sk), &wait);
return err;}
/** * af_alg_wmem_wakeup - wakeup caller when writable memory is available * * @sk: socket of connection to user space */void af_alg_wmem_wakeup(struct sock *sk){ struct socket_wq *wq;
if (!af_alg_writable(sk)) return;
rcu_read_lock(); wq = rcu_dereference(sk->sk_wq); if (skwq_has_sleeper(wq)) wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLRDNORM | EPOLLRDBAND); sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN); rcu_read_unlock();}EXPORT_SYMBOL_GPL(af_alg_wmem_wakeup);
/** * af_alg_wait_for_data - wait for availability of TX data * * @sk: socket of connection to user space * @flags: If MSG_DONTWAIT is set, then only report if function would sleep * @min: Set to minimum request size if partial requests are allowed. * Return: 0 when writable memory is available, < 0 upon error */int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min){ DEFINE_WAIT_FUNC(wait, woken_wake_function); struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; long timeout; int err = -ERESTARTSYS;
if (flags & MSG_DONTWAIT) return -EAGAIN;
sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
add_wait_queue(sk_sleep(sk), &wait); for (;;) { if (signal_pending(current)) break; timeout = MAX_SCHEDULE_TIMEOUT; if (sk_wait_event(sk, &timeout, ctx->init && (!ctx->more || (min && ctx->used >= min)), &wait)) { err = 0; break; } } remove_wait_queue(sk_sleep(sk), &wait);
sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
return err;}EXPORT_SYMBOL_GPL(af_alg_wait_for_data);
/** * af_alg_data_wakeup - wakeup caller when new data can be sent to kernel * * @sk: socket of connection to user space */static void af_alg_data_wakeup(struct sock *sk){ struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; struct socket_wq *wq;
if (!ctx->used) return;
rcu_read_lock(); wq = rcu_dereference(sk->sk_wq); if (skwq_has_sleeper(wq)) wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | EPOLLRDNORM | EPOLLRDBAND); sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT); rcu_read_unlock();}
/** * af_alg_sendmsg - implementation of sendmsg system call handler * * The sendmsg system call handler obtains the user data and stores it * in ctx->tsgl_list. This implies allocation of the required numbers of * struct af_alg_tsgl. * * In addition, the ctx is filled with the information sent via CMSG. * * @sock: socket of connection to user space * @msg: message from user space * @size: size of message from user space * @ivsize: the size of the IV for the cipher operation to verify that the * user-space-provided IV has the right size * Return: the number of copied data upon success, < 0 upon error */int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size, unsigned int ivsize){ struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; struct af_alg_tsgl *sgl; struct af_alg_control con = {}; long copied = 0; bool enc = false; bool init = false; int err = 0;
if (msg->msg_controllen) { err = af_alg_cmsg_send(msg, &con); if (err) return err;
init = true; switch (con.op) { case ALG_OP_ENCRYPT: enc = true; break; case ALG_OP_DECRYPT: enc = false; break; default: return -EINVAL; }
if (con.iv && con.iv->ivlen != ivsize) return -EINVAL; }
lock_sock(sk); if (ctx->write) { release_sock(sk); return -EBUSY; } ctx->write = true;
if (ctx->init && !ctx->more) { if (ctx->used) { err = -EINVAL; goto unlock; }
pr_info_once( "%s sent an empty control message without MSG_MORE.\n", current->comm); } ctx->init = true;
if (init) { ctx->enc = enc; if (con.iv) memcpy(ctx->iv, con.iv->iv, ivsize);
ctx->aead_assoclen = con.aead_assoclen; }
while (size) { struct scatterlist *sg; size_t len = size; ssize_t plen;
/* use the existing memory in an allocated page */ if (ctx->merge) { sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list); sg = sgl->sg + sgl->cur - 1; len = min_t(size_t, len, PAGE_SIZE - sg->offset - sg->length);
err = memcpy_from_msg(page_address(sg_page(sg)) + sg->offset + sg->length, msg, len); if (err) goto unlock;
sg->length += len; ctx->merge = (sg->offset + sg->length) & (PAGE_SIZE - 1);
ctx->used += len; copied += len; size -= len; continue; }
ctx->merge = 0;
if (!af_alg_writable(sk)) { err = af_alg_wait_for_wmem(sk, msg->msg_flags); if (err) goto unlock; }
/* allocate a new page */ len = min_t(unsigned long, len, af_alg_sndbuf(sk));
err = af_alg_alloc_tsgl(sk); if (err) goto unlock;
sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list); sg = sgl->sg; if (sgl->cur) sg_unmark_end(sg + sgl->cur - 1);
do { struct page *pg; unsigned int i = sgl->cur;
plen = min_t(size_t, len, PAGE_SIZE);
pg = alloc_page(GFP_KERNEL); if (!pg) { err = -ENOMEM; goto unlock; }
sg_assign_page(sg + i, pg);
err = memcpy_from_msg(page_address(sg_page(sg + i)), msg, plen); if (err) { __free_page(sg_page(sg + i)); sg_assign_page(sg + i, NULL); goto unlock; }
sg[i].length = plen; len -= plen; ctx->used += plen; copied += plen; size -= plen; sgl->cur++; } while (len && sgl->cur < MAX_SGL_ENTS);
ctx->merge = plen & (PAGE_SIZE - 1);
if (!size) sg_mark_end(sg + sgl->cur - 1); }
err = 0;
ctx->more = msg->msg_flags & MSG_MORE;
unlock: af_alg_data_wakeup(sk); ctx->write = false; release_sock(sk);
return copied ?: err;}EXPORT_SYMBOL_GPL(af_alg_sendmsg);
/** * af_alg_free_resources - release resources required for crypto request * @areq: Request holding the TX and RX SGL */void af_alg_free_resources(struct af_alg_async_req *areq){ struct sock *sk = areq->sk; struct af_alg_ctx *ctx;
af_alg_free_areq_sgls(areq); sock_kfree_s(sk, areq, areq->areqlen);
ctx = alg_sk(sk)->private; ctx->inflight = false;}EXPORT_SYMBOL_GPL(af_alg_free_resources);
/** * af_alg_poll - poll system call handler * @file: file pointer * @sock: socket to poll * @wait: poll_table */__poll_t af_alg_poll(struct file *file, struct socket *sock, poll_table *wait){ struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; __poll_t mask;
sock_poll_wait(file, sock, wait); mask = 0;
if (!ctx->more || ctx->used) mask |= EPOLLIN | EPOLLRDNORM;
if (af_alg_writable(sk)) mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
return mask;}EXPORT_SYMBOL_GPL(af_alg_poll);
/** * af_alg_alloc_areq - allocate struct af_alg_async_req * * @sk: socket of connection to user space * @areqlen: size of struct af_alg_async_req + crypto_*_reqsize * Return: allocated data structure or ERR_PTR upon error */struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk, unsigned int areqlen){ struct af_alg_ctx *ctx = alg_sk(sk)->private; struct af_alg_async_req *areq;
/* Only one request can be in flight. */ if (WARN_ON_ONCE(ctx->inflight)) return ERR_PTR(-EBUSY);
areq = sock_kmalloc(sk, areqlen, GFP_KERNEL); if (unlikely(!areq)) return ERR_PTR(-ENOMEM);
memset(areq, 0, areqlen);
ctx->inflight = true;
areq->areqlen = areqlen; areq->sk = sk; areq->first_rsgl.sgl.sgt.sgl = areq->first_rsgl.sgl.sgl; INIT_LIST_HEAD(&areq->rsgl_list);
return areq;}EXPORT_SYMBOL_GPL(af_alg_alloc_areq);
/** * af_alg_get_rsgl - create the RX SGL for the output data from the crypto * operation * * @sk: socket of connection to user space * @msg: user space message * @flags: flags used to invoke recvmsg with * @areq: instance of the cryptographic request that will hold the RX SGL * @maxsize: maximum number of bytes to be pulled from user space * @outlen: number of bytes in the RX SGL * Return: 0 on success, < 0 upon error */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){ struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; size_t len = 0;
while (maxsize > len && msg_data_left(msg)) { struct af_alg_rsgl *rsgl; ssize_t err; size_t seglen;
/* limit the amount of readable buffers */ if (!af_alg_readable(sk)) break;
seglen = min_t(size_t, (maxsize - len), msg_data_left(msg)); /* Never pin more pages than the remaining RX accounting budget. */ seglen = min_t(size_t, seglen, af_alg_rcvbuf(sk));
if (list_empty(&areq->rsgl_list)) { rsgl = &areq->first_rsgl; } else { rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL); if (unlikely(!rsgl)) return -ENOMEM; }
rsgl->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter); rsgl->sgl.sgt.sgl = rsgl->sgl.sgl; rsgl->sgl.sgt.nents = 0; rsgl->sgl.sgt.orig_nents = 0; list_add_tail(&rsgl->list, &areq->rsgl_list);
sg_init_table(rsgl->sgl.sgt.sgl, ALG_MAX_PAGES); err = extract_iter_to_sg(&msg->msg_iter, seglen, &rsgl->sgl.sgt, ALG_MAX_PAGES, 0); if (err < 0) { rsgl->sg_num_bytes = 0; return err; }
sg_mark_end(rsgl->sgl.sgt.sgl + rsgl->sgl.sgt.nents - 1);
/* chain the new scatterlist with previous one */ if (areq->last_rsgl) af_alg_link_sg(&areq->last_rsgl->sgl, &rsgl->sgl);
areq->last_rsgl = rsgl; len += err; atomic_add(err, &ctx->rcvused); rsgl->sg_num_bytes = err; }
*outlen = len; return 0;}EXPORT_SYMBOL_GPL(af_alg_get_rsgl);
static int __init af_alg_init(void){ int err;
af_alg_header = register_sysctl("crypto", af_alg_table);
err = proto_register(&alg_proto, 0); if (err) goto out_unregister_sysctl;
err = sock_register(&alg_family); if (err) goto out_unregister_proto;
return 0;
out_unregister_proto: proto_unregister(&alg_proto);out_unregister_sysctl: unregister_sysctl_table(af_alg_header); return err;}
static void __exit af_alg_exit(void){ sock_unregister(PF_ALG); proto_unregister(&alg_proto); unregister_sysctl_table(af_alg_header);}
module_init(af_alg_init);module_exit(af_alg_exit);MODULE_DESCRIPTION("Crypto userspace interface");MODULE_LICENSE("GPL");MODULE_ALIAS_NETPROTO(AF_ALG);