aboutsummaryrefslogtreecommitdiffstats
path: root/crypto/algif_aead.c
diff options
context:
space:
mode:
Diffstat (limited to 'crypto/algif_aead.c')
-rw-r--r--crypto/algif_aead.c864
1 files changed, 250 insertions, 614 deletions
diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index be117495eb43..516b38c3a169 100644
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c
@@ -5,88 +5,56 @@
*
* This file provides the user-space API for AEAD ciphers.
*
- * This file is derived from algif_skcipher.c.
- *
* 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.
+ *
+ * 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 sendpage/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 <crypto/internal/aead.h>
#include <crypto/scatterwalk.h>
#include <crypto/if_alg.h>
+#include <crypto/skcipher.h>
+#include <crypto/null.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/kernel.h>
-#include <linux/sched/signal.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/net.h>
#include <net/sock.h>
-struct aead_sg_list {
- unsigned int cur;
- struct scatterlist sg[ALG_MAX_PAGES];
-};
-
-struct aead_async_rsgl {
- struct af_alg_sgl sgl;
- struct list_head list;
-};
-
-struct aead_async_req {
- struct scatterlist *tsgl;
- struct aead_async_rsgl first_rsgl;
- struct list_head list;
- struct kiocb *iocb;
- struct sock *sk;
- unsigned int tsgls;
- char iv[];
-};
-
struct aead_tfm {
struct crypto_aead *aead;
bool has_key;
+ struct crypto_skcipher *null_tfm;
};
-struct aead_ctx {
- struct aead_sg_list tsgl;
- struct aead_async_rsgl first_rsgl;
- struct list_head list;
-
- void *iv;
-
- struct af_alg_completion completion;
-
- unsigned long used;
-
- unsigned int len;
- bool more;
- bool merge;
- bool enc;
-
- size_t aead_assoclen;
- struct aead_request aead_req;
-};
-
-static inline int aead_sndbuf(struct sock *sk)
+static inline bool aead_sufficient_data(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
- struct aead_ctx *ctx = ask->private;
-
- return max_t(int, max_t(int, sk->sk_sndbuf & PAGE_MASK, PAGE_SIZE) -
- ctx->used, 0);
-}
-
-static inline bool aead_writable(struct sock *sk)
-{
- return PAGE_SIZE <= aead_sndbuf(sk);
-}
-
-static inline bool aead_sufficient_data(struct aead_ctx *ctx)
-{
- unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req));
+ struct sock *psk = ask->parent;
+ struct alg_sock *pask = alg_sk(psk);
+ struct af_alg_ctx *ctx = ask->private;
+ struct aead_tfm *aeadc = pask->private;
+ struct crypto_aead *tfm = aeadc->aead;
+ unsigned int as = crypto_aead_authsize(tfm);
/*
* The minimum amount of memory needed for an AEAD cipher is
@@ -95,484 +63,58 @@ static inline bool aead_sufficient_data(struct aead_ctx *ctx)
return ctx->used >= ctx->aead_assoclen + (ctx->enc ? 0 : as);
}
-static void aead_reset_ctx(struct aead_ctx *ctx)
-{
- struct aead_sg_list *sgl = &ctx->tsgl;
-
- sg_init_table(sgl->sg, ALG_MAX_PAGES);
- sgl->cur = 0;
- ctx->used = 0;
- ctx->more = 0;
- ctx->merge = 0;
-}
-
-static void aead_put_sgl(struct sock *sk)
-{
- struct alg_sock *ask = alg_sk(sk);
- struct aead_ctx *ctx = ask->private;
- struct aead_sg_list *sgl = &ctx->tsgl;
- struct scatterlist *sg = sgl->sg;
- unsigned int i;
-
- for (i = 0; i < sgl->cur; i++) {
- if (!sg_page(sg + i))
- continue;
-
- put_page(sg_page(sg + i));
- sg_assign_page(sg + i, NULL);
- }
- aead_reset_ctx(ctx);
-}
-
-static void aead_wmem_wakeup(struct sock *sk)
-{
- struct socket_wq *wq;
-
- if (!aead_writable(sk))
- return;
-
- rcu_read_lock();
- wq = rcu_dereference(sk->sk_wq);
- if (skwq_has_sleeper(wq))
- wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
- POLLRDNORM |
- POLLRDBAND);
- sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
- rcu_read_unlock();
-}
-
-static int aead_wait_for_data(struct sock *sk, unsigned flags)
-{
- DEFINE_WAIT_FUNC(wait, woken_wake_function);
- struct alg_sock *ask = alg_sk(sk);
- struct aead_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->more, &wait)) {
- err = 0;
- break;
- }
- }
- remove_wait_queue(sk_sleep(sk), &wait);
-
- sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
-
- return err;
-}
-
-static void aead_data_wakeup(struct sock *sk)
-{
- struct alg_sock *ask = alg_sk(sk);
- struct aead_ctx *ctx = ask->private;
- struct socket_wq *wq;
-
- if (ctx->more)
- return;
- 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, POLLOUT |
- POLLRDNORM |
- POLLRDBAND);
- sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
- rcu_read_unlock();
-}
-
static int aead_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
{
struct sock *sk = sock->sk;
struct alg_sock *ask = alg_sk(sk);
- struct aead_ctx *ctx = ask->private;
- unsigned ivsize =
- crypto_aead_ivsize(crypto_aead_reqtfm(&ctx->aead_req));
- struct aead_sg_list *sgl = &ctx->tsgl;
- struct af_alg_control con = {};
- long copied = 0;
- bool enc = 0;
- bool init = 0;
- int err = -EINVAL;
-
- if (msg->msg_controllen) {
- err = af_alg_cmsg_send(msg, &con);
- if (err)
- return err;
-
- init = 1;
- switch (con.op) {
- case ALG_OP_ENCRYPT:
- enc = 1;
- break;
- case ALG_OP_DECRYPT:
- enc = 0;
- break;
- default:
- return -EINVAL;
- }
-
- if (con.iv && con.iv->ivlen != ivsize)
- return -EINVAL;
- }
-
- lock_sock(sk);
- if (!ctx->more && ctx->used)
- goto unlock;
-
- if (init) {
- ctx->enc = enc;
- if (con.iv)
- memcpy(ctx->iv, con.iv->iv, ivsize);
-
- ctx->aead_assoclen = con.aead_assoclen;
- }
-
- while (size) {
- size_t len = size;
- struct scatterlist *sg = NULL;
-
- /* use the existing memory in an allocated page */
- if (ctx->merge) {
- sg = sgl->sg + sgl->cur - 1;
- len = min_t(unsigned long, 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;
- }
-
- if (!aead_writable(sk)) {
- /* user space sent too much data */
- aead_put_sgl(sk);
- err = -EMSGSIZE;
- goto unlock;
- }
-
- /* allocate a new page */
- len = min_t(unsigned long, size, aead_sndbuf(sk));
- while (len) {
- size_t plen = 0;
-
- if (sgl->cur >= ALG_MAX_PAGES) {
- aead_put_sgl(sk);
- err = -E2BIG;
- goto unlock;
- }
-
- sg = sgl->sg + sgl->cur;
- plen = min_t(size_t, len, PAGE_SIZE);
-
- sg_assign_page(sg, alloc_page(GFP_KERNEL));
- err = -ENOMEM;
- if (!sg_page(sg))
- goto unlock;
-
- err = memcpy_from_msg(page_address(sg_page(sg)),
- msg, plen);
- if (err) {
- __free_page(sg_page(sg));
- sg_assign_page(sg, NULL);
- goto unlock;
- }
-
- sg->offset = 0;
- sg->length = plen;
- len -= plen;
- ctx->used += plen;
- copied += plen;
- sgl->cur++;
- size -= plen;
- ctx->merge = plen & (PAGE_SIZE - 1);
- }
- }
-
- err = 0;
-
- ctx->more = msg->msg_flags & MSG_MORE;
- if (!ctx->more && !aead_sufficient_data(ctx)) {
- aead_put_sgl(sk);
- err = -EMSGSIZE;
- }
-
-unlock:
- aead_data_wakeup(sk);
- release_sock(sk);
-
- return err ?: copied;
-}
-
-static ssize_t aead_sendpage(struct socket *sock, struct page *page,
- int offset, size_t size, int flags)
-{
- struct sock *sk = sock->sk;
- struct alg_sock *ask = alg_sk(sk);
- struct aead_ctx *ctx = ask->private;
- struct aead_sg_list *sgl = &ctx->tsgl;
- int err = -EINVAL;
-
- if (flags & MSG_SENDPAGE_NOTLAST)
- flags |= MSG_MORE;
-
- if (sgl->cur >= ALG_MAX_PAGES)
- return -E2BIG;
-
- lock_sock(sk);
- if (!ctx->more && ctx->used)
- goto unlock;
-
- if (!size)
- goto done;
-
- if (!aead_writable(sk)) {
- /* user space sent too much data */
- aead_put_sgl(sk);
- err = -EMSGSIZE;
- goto unlock;
- }
-
- ctx->merge = 0;
-
- get_page(page);
- sg_set_page(sgl->sg + sgl->cur, page, size, offset);
- sgl->cur++;
- ctx->used += size;
-
- err = 0;
-
-done:
- ctx->more = flags & MSG_MORE;
- if (!ctx->more && !aead_sufficient_data(ctx)) {
- aead_put_sgl(sk);
- err = -EMSGSIZE;
- }
+ struct sock *psk = ask->parent;
+ struct alg_sock *pask = alg_sk(psk);
+ struct aead_tfm *aeadc = pask->private;
+ struct crypto_aead *tfm = aeadc->aead;
+ unsigned int ivsize = crypto_aead_ivsize(tfm);
-unlock:
- aead_data_wakeup(sk);
- release_sock(sk);
-
- return err ?: size;
+ return af_alg_sendmsg(sock, msg, size, ivsize);
}
-#define GET_ASYM_REQ(req, tfm) (struct aead_async_req *) \
- ((char *)req + sizeof(struct aead_request) + \
- crypto_aead_reqsize(tfm))
-
- #define GET_REQ_SIZE(tfm) sizeof(struct aead_async_req) + \
- crypto_aead_reqsize(tfm) + crypto_aead_ivsize(tfm) + \
- sizeof(struct aead_request)
-
-static void aead_async_cb(struct crypto_async_request *_req, int err)
+static int crypto_aead_copy_sgl(struct crypto_skcipher *null_tfm,
+ struct scatterlist *src,
+ struct scatterlist *dst, unsigned int len)
{
- struct aead_request *req = _req->data;
- struct crypto_aead *tfm = crypto_aead_reqtfm(req);
- struct aead_async_req *areq = GET_ASYM_REQ(req, tfm);
- struct sock *sk = areq->sk;
- struct scatterlist *sg = areq->tsgl;
- struct aead_async_rsgl *rsgl;
- struct kiocb *iocb = areq->iocb;
- unsigned int i, reqlen = GET_REQ_SIZE(tfm);
-
- list_for_each_entry(rsgl, &areq->list, list) {
- af_alg_free_sg(&rsgl->sgl);
- if (rsgl != &areq->first_rsgl)
- sock_kfree_s(sk, rsgl, sizeof(*rsgl));
- }
+ SKCIPHER_REQUEST_ON_STACK(skreq, null_tfm);
- for (i = 0; i < areq->tsgls; i++)
- put_page(sg_page(sg + i));
+ skcipher_request_set_tfm(skreq, null_tfm);
+ skcipher_request_set_callback(skreq, CRYPTO_TFM_REQ_MAY_BACKLOG,
+ NULL, NULL);
+ skcipher_request_set_crypt(skreq, src, dst, len, NULL);
- sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls);
- sock_kfree_s(sk, req, reqlen);
- __sock_put(sk);
- iocb->ki_complete(iocb, err, err);
+ return crypto_skcipher_encrypt(skreq);
}
-static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg,
- int flags)
+static int _aead_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 aead_ctx *ctx = ask->private;
- struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req);
- struct aead_async_req *areq;
- struct aead_request *req = NULL;
- struct aead_sg_list *sgl = &ctx->tsgl;
- struct aead_async_rsgl *last_rsgl = NULL, *rsgl;
+ struct sock *psk = ask->parent;
+ struct alg_sock *pask = alg_sk(psk);
+ struct af_alg_ctx *ctx = ask->private;
+ struct aead_tfm *aeadc = pask->private;
+ struct crypto_aead *tfm = aeadc->aead;
+ struct crypto_skcipher *null_tfm = aeadc->null_tfm;
unsigned int as = crypto_aead_authsize(tfm);
- unsigned int i, reqlen = GET_REQ_SIZE(tfm);
- int err = -ENOMEM;
- unsigned long used;
- size_t outlen = 0;
- size_t usedpages = 0;
-
- lock_sock(sk);
- if (ctx->more) {
- err = aead_wait_for_data(sk, flags);
- if (err)
- goto unlock;
- }
-
- if (!aead_sufficient_data(ctx))
- goto unlock;
-
- used = ctx->used;
- if (ctx->enc)
- outlen = used + as;
- else
- outlen = used - as;
-
- req = sock_kmalloc(sk, reqlen, GFP_KERNEL);
- if (unlikely(!req))
- goto unlock;
-
- areq = GET_ASYM_REQ(req, tfm);
- memset(&areq->first_rsgl, '\0', sizeof(areq->first_rsgl));
- INIT_LIST_HEAD(&areq->list);
- areq->iocb = msg->msg_iocb;
- areq->sk = sk;
- memcpy(areq->iv, ctx->iv, crypto_aead_ivsize(tfm));
- aead_request_set_tfm(req, tfm);
- aead_request_set_ad(req, ctx->aead_assoclen);
- aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
- aead_async_cb, req);
- used -= ctx->aead_assoclen;
-
- /* take over all tx sgls from ctx */
- areq->tsgl = sock_kmalloc(sk,
- sizeof(*areq->tsgl) * max_t(u32, sgl->cur, 1),
- GFP_KERNEL);
- if (unlikely(!areq->tsgl))
- goto free;
-
- sg_init_table(areq->tsgl, max_t(u32, sgl->cur, 1));
- for (i = 0; i < sgl->cur; i++)
- sg_set_page(&areq->tsgl[i], sg_page(&sgl->sg[i]),
- sgl->sg[i].length, sgl->sg[i].offset);
-
- areq->tsgls = sgl->cur;
-
- /* create rx sgls */
- while (outlen > usedpages && iov_iter_count(&msg->msg_iter)) {
- size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter),
- (outlen - usedpages));
-
- if (list_empty(&areq->list)) {
- rsgl = &areq->first_rsgl;
-
- } else {
- rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
- if (unlikely(!rsgl)) {
- err = -ENOMEM;
- goto free;
- }
- }
- rsgl->sgl.npages = 0;
- list_add_tail(&rsgl->list, &areq->list);
-
- /* make one iovec available as scatterlist */
- err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
- if (err < 0)
- goto free;
-
- usedpages += err;
-
- /* chain the new scatterlist with previous one */
- if (last_rsgl)
- af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
-
- last_rsgl = rsgl;
-
- iov_iter_advance(&msg->msg_iter, err);
- }
-
- /* ensure output buffer is sufficiently large */
- if (usedpages < outlen) {
- err = -EINVAL;
- goto unlock;
- }
-
- aead_request_set_crypt(req, areq->tsgl, areq->first_rsgl.sgl.sg, used,
- areq->iv);
- err = ctx->enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req);
- if (err) {
- if (err == -EINPROGRESS) {
- sock_hold(sk);
- err = -EIOCBQUEUED;
- aead_reset_ctx(ctx);
- goto unlock;
- } else if (err == -EBADMSG) {
- aead_put_sgl(sk);
- }
- goto free;
- }
- aead_put_sgl(sk);
-
-free:
- list_for_each_entry(rsgl, &areq->list, list) {
- af_alg_free_sg(&rsgl->sgl);
- if (rsgl != &areq->first_rsgl)
- sock_kfree_s(sk, rsgl, sizeof(*rsgl));
- }
- if (areq->tsgl)
- sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls);
- if (req)
- sock_kfree_s(sk, req, reqlen);
-unlock:
- aead_wmem_wakeup(sk);
- release_sock(sk);
- return err ? err : outlen;
-}
-
-static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags)
-{
- struct sock *sk = sock->sk;
- struct alg_sock *ask = alg_sk(sk);
- struct aead_ctx *ctx = ask->private;
- unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req));
- struct aead_sg_list *sgl = &ctx->tsgl;
- struct aead_async_rsgl *last_rsgl = NULL;
- struct aead_async_rsgl *rsgl, *tmp;
- int err = -EINVAL;
- unsigned long used = 0;
- size_t outlen = 0;
- size_t usedpages = 0;
-
- lock_sock(sk);
+ struct af_alg_async_req *areq;
+ struct af_alg_tsgl *tsgl;
+ struct scatterlist *src;
+ int err = 0;
+ size_t used = 0; /* [in] TX bufs to be en/decrypted */
+ size_t outlen = 0; /* [out] RX bufs produced by kernel */
+ size_t usedpages = 0; /* [in] RX bufs to be used from user */
+ size_t processed = 0; /* [in] TX bufs to be consumed */
/*
- * Please see documentation of aead_request_set_crypt for the
- * description of the AEAD memory structure expected from the caller.
+ * Data length provided by caller via sendmsg/sendpage that has not
+ * yet been processed.
*/
-
- if (ctx->more) {
- err = aead_wait_for_data(sk, flags);
- if (err)
- goto unlock;
- }
-
- /* data length provided by caller via sendmsg/sendpage */
used = ctx->used;
/*
@@ -584,8 +126,8 @@ static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags)
* the error message in sendmsg/sendpage and still call recvmsg. This
* check here protects the kernel integrity.
*/
- if (!aead_sufficient_data(ctx))
- goto unlock;
+ if (!aead_sufficient_data(sk))
+ return -EINVAL;
/*
* Calculate the minimum output buffer size holding the result of the
@@ -606,104 +148,191 @@ static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags)
*/
used -= ctx->aead_assoclen;
- /* convert iovecs of output buffers into scatterlists */
- while (outlen > usedpages && iov_iter_count(&msg->msg_iter)) {
- size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter),
- (outlen - usedpages));
-
- if (list_empty(&ctx->list)) {
- rsgl = &ctx->first_rsgl;
- } else {
- rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
- if (unlikely(!rsgl)) {
- err = -ENOMEM;
- goto unlock;
- }
- }
- rsgl->sgl.npages = 0;
- list_add_tail(&rsgl->list, &ctx->list);
+ /* Allocate cipher request for current operation. */
+ areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) +
+ crypto_aead_reqsize(tfm));
+ if (IS_ERR(areq))
+ return PTR_ERR(areq);
- /* make one iovec available as scatterlist */
- err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
- if (err < 0)
- goto unlock;
- usedpages += err;
- /* chain the new scatterlist with previous one */
- if (last_rsgl)
- af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
+ /* convert iovecs of output buffers into RX SGL */
+ err = af_alg_get_rsgl(sk, msg, flags, areq, outlen, &usedpages);
+ if (err)
+ goto free;
- last_rsgl = rsgl;
+ /*
+ * Ensure output buffer is sufficiently large. If the caller provides
+ * less buffer space, only use the relative required input size. This
+ * allows AIO operation where the caller sent all data to be processed
+ * and the AIO operation performs the operation on the different chunks
+ * of the input data.
+ */
+ if (usedpages < outlen) {
+ size_t less = outlen - usedpages;
- iov_iter_advance(&msg->msg_iter, err);
+ if (used < less) {
+ err = -EINVAL;
+ goto free;
+ }
+ used -= less;
+ outlen -= less;
}
- /* ensure output buffer is sufficiently large */
- if (usedpages < outlen) {
- err = -EINVAL;
- goto unlock;
- }
+ processed = used + ctx->aead_assoclen;
+ tsgl = list_first_entry(&ctx->tsgl_list, struct af_alg_tsgl, list);
- sg_mark_end(sgl->sg + sgl->cur - 1);
- aead_request_set_crypt(&ctx->aead_req, sgl->sg, ctx->first_rsgl.sgl.sg,
- used, ctx->iv);
- aead_request_set_ad(&ctx->aead_req, ctx->aead_assoclen);
+ /*
+ * Copy of AAD from source to destination
+ *
+ * The AAD is copied to the destination buffer without change. Even
+ * when user space uses an in-place cipher operation, the kernel
+ * will copy the data as it does not see whether such in-place operation
+ * is initiated.
+ *
+ * To ensure efficiency, the following implementation ensure that the
+ * ciphers are invoked to perform a crypto operation in-place. This
+ * is achieved by memory management specified as follows.
+ */
- err = af_alg_wait_for_completion(ctx->enc ?
- crypto_aead_encrypt(&ctx->aead_req) :
- crypto_aead_decrypt(&ctx->aead_req),
- &ctx->completion);
+ /* Use the RX SGL as source (and destination) for crypto op. */
+ src = areq->first_rsgl.sgl.sg;
+
+ if (ctx->enc) {
+ /*
+ * Encryption operation - The in-place cipher operation is
+ * achieved by the following operation:
+ *
+ * TX SGL: AAD || PT
+ * | |
+ * | copy |
+ * v v
+ * RX SGL: AAD || PT || Tag
+ */
+ err = crypto_aead_copy_sgl(null_tfm, tsgl->sg,
+ areq->first_rsgl.sgl.sg, processed);
+ if (err)
+ goto free;
+ af_alg_pull_tsgl(sk, processed, NULL, 0);
+ } else {
+ /*
+ * Decryption operation - To achieve an in-place cipher
+ * operation, the following SGL structure is used:
+ *
+ * TX SGL: AAD || CT || Tag
+ * | | ^
+ * | copy | | Create SGL link.
+ * v v |
+ * RX SGL: AAD || CT ----+
+ */
+
+ /* Copy AAD || CT to RX SGL buffer for in-place operation. */
+ err = crypto_aead_copy_sgl(null_tfm, tsgl->sg,
+ areq->first_rsgl.sgl.sg, outlen);
+ if (err)
+ goto free;
- if (err) {
- /* EBADMSG implies a valid cipher operation took place */
- if (err == -EBADMSG)
- aead_put_sgl(sk);
+ /* Create TX SGL for tag and chain it to RX SGL. */
+ areq->tsgl_entries = af_alg_count_tsgl(sk, processed,
+ processed - as);
+ if (!areq->tsgl_entries)
+ areq->tsgl_entries = 1;
+ areq->tsgl = sock_kmalloc(sk, sizeof(*areq->tsgl) *
+ areq->tsgl_entries,
+ GFP_KERNEL);
+ if (!areq->tsgl) {
+ err = -ENOMEM;
+ goto free;
+ }
+ sg_init_table(areq->tsgl, areq->tsgl_entries);
+
+ /* Release TX SGL, except for tag data and reassign tag data. */
+ af_alg_pull_tsgl(sk, processed, areq->tsgl, processed - as);
+
+ /* chain the areq TX SGL holding the tag with RX SGL */
+ if (usedpages) {
+ /* RX SGL present */
+ struct af_alg_sgl *sgl_prev = &areq->last_rsgl->sgl;
+
+ sg_unmark_end(sgl_prev->sg + sgl_prev->npages - 1);
+ sg_chain(sgl_prev->sg, sgl_prev->npages + 1,
+ areq->tsgl);
+ } else
+ /* no RX SGL present (e.g. authentication only) */
+ src = areq->tsgl;
+ }
- goto unlock;
+ /* Initialize the crypto operation */
+ aead_request_set_crypt(&areq->cra_u.aead_req, src,
+ areq->first_rsgl.sgl.sg, used, ctx->iv);
+ aead_request_set_ad(&areq->cra_u.aead_req, ctx->aead_assoclen);
+ aead_request_set_tfm(&areq->cra_u.aead_req, tfm);
+
+ if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
+ /* AIO operation */
+ areq->iocb = msg->msg_iocb;
+ aead_request_set_callback(&areq->cra_u.aead_req,
+ CRYPTO_TFM_REQ_MAY_BACKLOG,
+ af_alg_async_cb, areq);
+ err = ctx->enc ? crypto_aead_encrypt(&areq->cra_u.aead_req) :
+ crypto_aead_decrypt(&areq->cra_u.aead_req);
+ } else {
+ /* Synchronous operation */
+ aead_request_set_callback(&areq->cra_u.aead_req,
+ CRYPTO_TFM_REQ_MAY_BACKLOG,
+ af_alg_complete, &ctx->completion);
+ err = af_alg_wait_for_completion(ctx->enc ?
+ crypto_aead_encrypt(&areq->cra_u.aead_req) :
+ crypto_aead_decrypt(&areq->cra_u.aead_req),
+ &ctx->completion);
}
- aead_put_sgl(sk);
- err = 0;
+ /* AIO operation in progress */
+ if (err == -EINPROGRESS) {
+ sock_hold(sk);
-unlock:
- list_for_each_entry_safe(rsgl, tmp, &ctx->list, list) {
- af_alg_free_sg(&rsgl->sgl);
- list_del(&rsgl->list);
- if (rsgl != &ctx->first_rsgl)
- sock_kfree_s(sk, rsgl, sizeof(*rsgl));
+ /* Remember output size that will be generated. */
+ areq->outlen = outlen;
+
+ return -EIOCBQUEUED;
}
- INIT_LIST_HEAD(&ctx->list);
- aead_wmem_wakeup(sk);
- release_sock(sk);
- return err ? err : outlen;
-}
+free:
+ af_alg_free_areq_sgls(areq);
+ sock_kfree_s(sk, areq, areq->areqlen);
-static int aead_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored,
- int flags)
-{
- return (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) ?
- aead_recvmsg_async(sock, msg, flags) :
- aead_recvmsg_sync(sock, msg, flags);
+ return err ? err : outlen;
}
-static unsigned int aead_poll(struct file *file, struct socket *sock,
- poll_table *wait)
+static int aead_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 aead_ctx *ctx = ask->private;
- unsigned int mask;
-
- sock_poll_wait(file, sk_sleep(sk), wait);
- mask = 0;
+ int ret = 0;
- if (!ctx->more)
- mask |= POLLIN | POLLRDNORM;
+ lock_sock(sk);
+ while (msg_data_left(msg)) {
+ int err = _aead_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 || err == -EBADMSG || !ret)
+ ret = err;
+ goto out;
+ }
- if (aead_writable(sk))
- mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
+ ret += err;
+ }
- return mask;
+out:
+ af_alg_wmem_wakeup(sk);
+ release_sock(sk);
+ return ret;
}
static struct proto_ops algif_aead_ops = {
@@ -723,9 +352,9 @@ static struct proto_ops algif_aead_ops = {
.release = af_alg_release,
.sendmsg = aead_sendmsg,
- .sendpage = aead_sendpage,
+ .sendpage = af_alg_sendpage,
.recvmsg = aead_recvmsg,
- .poll = aead_poll,
+ .poll = af_alg_poll,
};
static int aead_check_key(struct socket *sock)
@@ -787,7 +416,7 @@ static ssize_t aead_sendpage_nokey(struct socket *sock, struct page *page,
if (err)
return err;
- return aead_sendpage(sock, page, offset, size, flags);
+ return af_alg_sendpage(sock, page, offset, size, flags);
}
static int aead_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
@@ -821,13 +450,14 @@ static struct proto_ops algif_aead_ops_nokey = {
.sendmsg = aead_sendmsg_nokey,
.sendpage = aead_sendpage_nokey,
.recvmsg = aead_recvmsg_nokey,
- .poll = aead_poll,
+ .poll = af_alg_poll,
};
static void *aead_bind(const char *name, u32 type, u32 mask)
{
struct aead_tfm *tfm;
struct crypto_aead *aead;
+ struct crypto_skcipher *null_tfm;
tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
if (!tfm)
@@ -839,7 +469,15 @@ static void *aead_bind(const char *name, u32 type, u32 mask)
return ERR_CAST(aead);
}
+ null_tfm = crypto_get_default_null_skcipher2();
+ if (IS_ERR(null_tfm)) {
+ crypto_free_aead(aead);
+ kfree(tfm);
+ return ERR_CAST(null_tfm);
+ }
+
tfm->aead = aead;
+ tfm->null_tfm = null_tfm;
return tfm;
}
@@ -873,12 +511,15 @@ static int aead_setkey(void *private, const u8 *key, unsigned int keylen)
static void aead_sock_destruct(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
- struct aead_ctx *ctx = ask->private;
- unsigned int ivlen = crypto_aead_ivsize(
- crypto_aead_reqtfm(&ctx->aead_req));
-
- WARN_ON(refcount_read(&sk->sk_refcnt) != 0);
- aead_put_sgl(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ struct sock *psk = ask->parent;
+ struct alg_sock *pask = alg_sk(psk);
+ struct aead_tfm *aeadc = pask->private;
+ struct crypto_aead *tfm = aeadc->aead;
+ unsigned int ivlen = crypto_aead_ivsize(tfm);
+
+ af_alg_pull_tsgl(sk, ctx->used, NULL, 0);
+ crypto_put_default_null_skcipher2();
sock_kzfree_s(sk, ctx->iv, ivlen);
sock_kfree_s(sk, ctx, ctx->len);
af_alg_release_parent(sk);
@@ -886,11 +527,11 @@ static void aead_sock_destruct(struct sock *sk)
static int aead_accept_parent_nokey(void *private, struct sock *sk)
{
- struct aead_ctx *ctx;
+ struct af_alg_ctx *ctx;
struct alg_sock *ask = alg_sk(sk);
struct aead_tfm *tfm = private;
struct crypto_aead *aead = tfm->aead;
- unsigned int len = sizeof(*ctx) + crypto_aead_reqsize(aead);
+ unsigned int len = sizeof(*ctx);
unsigned int ivlen = crypto_aead_ivsize(aead);
ctx = sock_kmalloc(sk, len, GFP_KERNEL);
@@ -905,23 +546,18 @@ static int aead_accept_parent_nokey(void *private, struct sock *sk)
}
memset(ctx->iv, 0, ivlen);
+ INIT_LIST_HEAD(&ctx->tsgl_list);
ctx->len = len;
ctx->used = 0;
+ ctx->rcvused = 0;
ctx->more = 0;
ctx->merge = 0;
ctx->enc = 0;
- ctx->tsgl.cur = 0;
ctx->aead_assoclen = 0;
af_alg_init_completion(&ctx->completion);
- sg_init_table(ctx->tsgl.sg, ALG_MAX_PAGES);
- INIT_LIST_HEAD(&ctx->list);
ask->private = ctx;
- aead_request_set_tfm(&ctx->aead_req, aead);
- aead_request_set_callback(&ctx->aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
- af_alg_complete, &ctx->completion);
-
sk->sk_destruct = aead_sock_destruct;
return 0;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.