static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
const unsigned char *iv, int enc)
{
int ciphertype;
int ret;
afalg_ctx *actx;
char ciphername[ALG_MAX_SALG_NAME];
if (ctx == NULL || key == NULL) {
ALG_WARN("%s: Null Parameter\n", __func__);
return 0;
}
if (EVP_CIPHER_CTX_cipher(ctx) == NULL) {
ALG_WARN("%s: Cipher object NULL\n", __func__);
return 0;
}
actx = EVP_CIPHER_CTX_get_cipher_data(ctx);
if (actx == NULL) {
ALG_WARN("%s: Cipher data NULL\n", __func__);
return 0;
}
ciphertype = EVP_CIPHER_CTX_nid(ctx);
switch (ciphertype) {
case NID_aes_128_cbc:
strncpy(ciphername, "cbc(aes)", ALG_MAX_SALG_NAME);
break;
default:
ALG_WARN("%s: Unsupported Cipher type %d\n", __func__, ciphertype);
return 0;
}
ciphername[ALG_MAX_SALG_NAME-1]='\0';
if (ALG_AES_IV_LEN != EVP_CIPHER_CTX_iv_length(ctx)) {
ALG_WARN("%s: Unsupported IV length :%d\n", __func__,
EVP_CIPHER_CTX_iv_length(ctx));
return 0;
}
/* Setup AFALG socket for crypto processing */
ret = afalg_create_sk(actx, "skcipher", ciphername);
if (ret < 1)
return 0;
ret = afalg_set_key(actx, key, EVP_CIPHER_CTX_key_length(ctx));
if (ret < 1)
goto err;
/* Setup AIO ctx to allow async AFALG crypto processing */
if (afalg_init_aio(&actx->aio) == 0)
goto err;
# ifdef ALG_ZERO_COPY
pipe(actx->zc_pipe);
# endif
actx->init_done = MAGIC_INIT_NUM;
return 1;
err:
close(actx->sfd);
close(actx->bfd);
return 0;
}
static int afalg_fin_cipher_aio(afalg_aio *aio, int sfd, unsigned char *buf,
size_t len)
{
int r;
int retry = 0;
unsigned int done = 0;
struct iocb *cb;
struct timespec timeout;
struct io_event events[MAX_INFLIGHTS];
u_int64_t eval = 0;
timeout.tv_sec = 0;
timeout.tv_nsec = 0;
/* if efd has not been initialised yet do it here */
if (aio->mode == MODE_UNINIT) {
r = afalg_setup_async_event_notification(aio);
if (r == 0)
return 0;
}
cb = &(aio->cbt[0 % MAX_INFLIGHTS]);
memset(cb, '\0', sizeof(*cb));
cb->aio_fildes = sfd;
cb->aio_lio_opcode = IOCB_CMD_PREAD;
/*
* The pointer has to be converted to unsigned value first to avoid
* sign extension on cast to 64 bit value in 32-bit builds
*/
cb->aio_buf = (size_t)buf;
cb->aio_offset = 0;
cb->aio_data = 0;
cb->aio_nbytes = len;
cb->aio_flags = IOCB_FLAG_RESFD;
cb->aio_resfd = aio->efd;
/*
* Perform AIO read on AFALG socket, this in turn performs an async
* crypto operation in kernel space
*/
r = io_read(aio->aio_ctx, 1, &cb);
if (r < 0) {
ALG_PWARN("%s(%d): io_read failed : ", __FILE__, __LINE__);
return 0;
}
do {
/* While AIO read is being performed pause job */
ASYNC_pause_job();
/* Check for completion of AIO read */
r = read(aio->efd, &eval, sizeof(eval));
if (r < 0) {
if (errno == EAGAIN || errno == EWOULDBLOCK)
continue;
ALG_PERR("%s(%d): read failed for event fd : ", __FILE__, __LINE__);
return 0;
} else if (r == 0 || eval <= 0) {
ALG_WARN("%s(%d): eventfd read %d bytes, eval = %lu\n", __FILE__,
__LINE__, r, eval);
}
if (eval > 0) {
/* Get results of AIO read */
r = io_getevents(aio->aio_ctx, 1, MAX_INFLIGHTS,
events, &timeout);
if (r > 0) {
/*
* events.res indicates the actual status of the operation.
* Handle the error condition first.
*/
if (events[0].res < 0) {
/*
* Underlying operation cannot be completed at the time
* of previous submission. Resubmit for the operation.
*/
if (events[0].res == -EBUSY && retry++ < 3) {
r = io_read(aio->aio_ctx, 1, &cb);
if (r < 0) {
ALG_PERR("%s(%d): retry %d for io_read failed : ",
__FILE__, __LINE__, retry);
return 0;
}
continue;
} else {
/*
* Retries exceed for -EBUSY or unrecoverable error
* condition for this instance of operation.
*/
ALG_WARN
("%s(%d): Crypto Operation failed with code %lld\n",
__FILE__, __LINE__, events[0].res);
return 0;
}
}
/* Operation successful. */
done = 1;
} else if (r < 0) {
ALG_PERR("%s(%d): io_getevents failed : ", __FILE__, __LINE__);
return 0;
} else {
ALG_WARN("%s(%d): io_geteventd read 0 bytes\n", __FILE__,
__LINE__);
}
}
} while (!done);
return 1;
}
static int afalg_start_cipher_sk(afalg_ctx *actx, const unsigned char *in,
size_t inl, const unsigned char *iv,
unsigned int enc)
{
struct msghdr msg = { 0 };
struct cmsghdr *cmsg;
struct iovec iov;
ssize_t sbytes;
# ifdef ALG_ZERO_COPY
int ret;
# endif
char cbuf[CMSG_SPACE(ALG_IV_LEN(ALG_AES_IV_LEN)) + CMSG_SPACE(ALG_OP_LEN)];
memset(cbuf, 0, sizeof(cbuf));
msg.msg_control = cbuf;
msg.msg_controllen = sizeof(cbuf);
/*
* cipher direction (i.e. encrypt or decrypt) and iv are sent to the
* kernel as part of sendmsg()'s ancillary data
*/
cmsg = CMSG_FIRSTHDR(&msg);
afalg_set_op_sk(cmsg, enc);
cmsg = CMSG_NXTHDR(&msg, cmsg);
afalg_set_iv_sk(cmsg, iv, ALG_AES_IV_LEN);
/* iov that describes input data */
iov.iov_base = (unsigned char *)in;
iov.iov_len = inl;
msg.msg_flags = MSG_MORE;
# ifdef ALG_ZERO_COPY
/*
* ZERO_COPY mode
* Works best when buffer is 4k aligned
* OPENS: out of place processing (i.e. out != in)
*/
/* Input data is not sent as part of call to sendmsg() */
msg.msg_iovlen = 0;
msg.msg_iov = NULL;
/* Sendmsg() sends iv and cipher direction to the kernel */
sbytes = sendmsg(actx->sfd, &msg, 0);
if (sbytes < 0) {
ALG_PERR("%s: sendmsg failed for zero copy cipher operation : ",
__func__);
return 0;
}
/*
* vmsplice and splice are used to pin the user space input buffer for
* kernel space processing avoiding copys from user to kernel space
*/
ret = vmsplice(actx->zc_pipe[1], &iov, 1, SPLICE_F_GIFT);
if (ret < 0) {
ALG_PERR("%s: vmsplice failed : ", __func__);
return 0;
}
ret = splice(actx->zc_pipe[0], NULL, actx->sfd, NULL, inl, 0);
if (ret < 0) {
ALG_PERR("%s: splice failed : ", __func__);
return 0;
}
# else
msg.msg_iovlen = 1;
msg.msg_iov = &iov;
/* Sendmsg() sends iv, cipher direction and input data to the kernel */
sbytes = sendmsg(actx->sfd, &msg, 0);
if (sbytes < 0) {
ALG_PERR("%s: sendmsg failed for cipher operation : ", __func__);
return 0;
}
if (sbytes != (ssize_t) inl) {
ALG_WARN("Cipher operation send bytes %zd != inlen %zd\n", sbytes,
inl);
return 0;
}
# endif
return 1;
}
