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author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2017-01-24 09:57:18 -0800 |
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committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2017-01-24 09:57:18 -0800 |
commit | 1ede28e658b8f2dd7c2ce9d3829742f9e5ea9fc9 (patch) | |
tree | 9fe0061d9e4c63f84ddf8674e88e35a82f3a8ae3 /crypto/algif_aead.c | |
parent | 38d20e9265b6677dd840e4ba4ef012a0044948a2 (diff) | |
parent | ba53933de8ea9024cdb1d3650f66da9f264d1bcc (diff) | |
download | linux-crypto-1ede28e658b8f2dd7c2ce9d3829742f9e5ea9fc9.tar.gz linux-crypto-1ede28e658b8f2dd7c2ce9d3829742f9e5ea9fc9.zip |
Merge tag 'v4.10-rc5' into for-linus
Sync up with mainline to apply fixup to a commit that came through
power supply tree.
Diffstat (limited to 'crypto/algif_aead.c')
-rw-r--r-- | crypto/algif_aead.c | 87 |
1 files changed, 46 insertions, 41 deletions
diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c index 80a0f1a7..f849311e 100644 --- a/crypto/algif_aead.c +++ b/crypto/algif_aead.c @@ -81,7 +81,11 @@ static inline bool aead_sufficient_data(struct aead_ctx *ctx) { unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req)); - return ctx->used >= ctx->aead_assoclen + as; + /* + * The minimum amount of memory needed for an AEAD cipher is + * the AAD and in case of decryption the tag. + */ + return ctx->used >= ctx->aead_assoclen + (ctx->enc ? 0 : as); } static void aead_reset_ctx(struct aead_ctx *ctx) @@ -132,28 +136,27 @@ static void aead_wmem_wakeup(struct sock *sk) 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; - DEFINE_WAIT(wait); 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; - prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); timeout = MAX_SCHEDULE_TIMEOUT; - if (sk_wait_event(sk, &timeout, !ctx->more)) { + if (sk_wait_event(sk, &timeout, !ctx->more, &wait)) { err = 0; break; } } - finish_wait(sk_sleep(sk), &wait); + remove_wait_queue(sk_sleep(sk), &wait); sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); @@ -416,7 +419,7 @@ static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg, unsigned int i, reqlen = GET_REQ_SIZE(tfm); int err = -ENOMEM; unsigned long used; - size_t outlen; + size_t outlen = 0; size_t usedpages = 0; lock_sock(sk); @@ -426,12 +429,15 @@ static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg, goto unlock; } - used = ctx->used; - outlen = used; - 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; @@ -445,15 +451,16 @@ static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg, aead_request_set_ad(req, ctx->aead_assoclen); aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, aead_async_cb, sk); - used -= ctx->aead_assoclen + (ctx->enc ? as : 0); + used -= ctx->aead_assoclen; /* take over all tx sgls from ctx */ - areq->tsgl = sock_kmalloc(sk, sizeof(*areq->tsgl) * sgl->cur, + 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, sgl->cur); + 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); @@ -461,7 +468,7 @@ static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg, areq->tsgls = sgl->cur; /* create rx sgls */ - while (iov_iter_count(&msg->msg_iter)) { + while (outlen > usedpages && iov_iter_count(&msg->msg_iter)) { size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter), (outlen - usedpages)); @@ -491,16 +498,14 @@ static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg, last_rsgl = rsgl; - /* we do not need more iovecs as we have sufficient memory */ - if (outlen <= usedpages) - break; - iov_iter_advance(&msg->msg_iter, err); } - err = -EINVAL; + /* ensure output buffer is sufficiently large */ - if (usedpages < outlen) - goto free; + if (usedpages < outlen) { + err = -EINVAL; + goto unlock; + } aead_request_set_crypt(req, areq->tsgl, areq->first_rsgl.sgl.sg, used, areq->iv); @@ -551,18 +556,8 @@ static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags) lock_sock(sk); /* - * AEAD memory structure: For encryption, the tag is appended to the - * ciphertext which implies that the memory allocated for the ciphertext - * must be increased by the tag length. For decryption, the tag - * is expected to be concatenated to the ciphertext. The plaintext - * therefore has a memory size of the ciphertext minus the tag length. - * - * The memory structure for cipher operation has the following - * structure: - * AEAD encryption input: assoc data || plaintext - * AEAD encryption output: cipherntext || auth tag - * AEAD decryption input: assoc data || ciphertext || auth tag - * AEAD decryption output: plaintext + * Please see documentation of aead_request_set_crypt for the + * description of the AEAD memory structure expected from the caller. */ if (ctx->more) { @@ -571,6 +566,7 @@ static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags) goto unlock; } + /* data length provided by caller via sendmsg/sendpage */ used = ctx->used; /* @@ -585,16 +581,27 @@ static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags) if (!aead_sufficient_data(ctx)) goto unlock; - outlen = used; + /* + * Calculate the minimum output buffer size holding the result of the + * cipher operation. When encrypting data, the receiving buffer is + * larger by the tag length compared to the input buffer as the + * encryption operation generates the tag. For decryption, the input + * buffer provides the tag which is consumed resulting in only the + * plaintext without a buffer for the tag returned to the caller. + */ + if (ctx->enc) + outlen = used + as; + else + outlen = used - as; /* * The cipher operation input data is reduced by the associated data * length as this data is processed separately later on. */ - used -= ctx->aead_assoclen + (ctx->enc ? as : 0); + used -= ctx->aead_assoclen; /* convert iovecs of output buffers into scatterlists */ - while (iov_iter_count(&msg->msg_iter)) { + while (outlen > usedpages && iov_iter_count(&msg->msg_iter)) { size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter), (outlen - usedpages)); @@ -621,16 +628,14 @@ static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags) last_rsgl = rsgl; - /* we do not need more iovecs as we have sufficient memory */ - if (outlen <= usedpages) - break; iov_iter_advance(&msg->msg_iter, err); } - err = -EINVAL; /* ensure output buffer is sufficiently large */ - if (usedpages < outlen) + if (usedpages < outlen) { + err = -EINVAL; goto unlock; + } sg_mark_end(sgl->sg + sgl->cur - 1); aead_request_set_crypt(&ctx->aead_req, sgl->sg, ctx->first_rsgl.sgl.sg, |