d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
9941cb0657
freebsd-dev/sys/opencrypto/criov.c
John Baldwin 9c0e3d3a53 Add support for optional separate output buffers to in-kernel crypto. 
Some crypto consumers such as GELI and KTLS for file-backed sendfile
need to store their output in a separate buffer from the input.
Currently these consumers copy the contents of the input buffer into
the output buffer and queue an in-place crypto operation on the output
buffer.  Using a separate output buffer avoids this copy.

- Create a new 'struct crypto_buffer' describing a crypto buffer
  containing a type and type-specific fields.  crp_ilen is gone,
  instead buffers that use a flat kernel buffer have a cb_buf_len
  field for their length.  The length of other buffer types is
  inferred from the backing store (e.g. uio_resid for a uio).
  Requests now have two such structures: crp_buf for the input buffer,
  and crp_obuf for the output buffer.

- Consumers now use helper functions (crypto_use_*,
  e.g. crypto_use_mbuf()) to configure the input buffer.  If an output
  buffer is not configured, the request still modifies the input
  buffer in-place.  A consumer uses a second set of helper functions
  (crypto_use_output_*) to configure an output buffer.

- Consumers must request support for separate output buffers when
  creating a crypto session via the CSP_F_SEPARATE_OUTPUT flag and are
  only permitted to queue a request with a separate output buffer on
  sessions with this flag set.  Existing drivers already reject
  sessions with unknown flags, so this permits drivers to be modified
  to support this extension without requiring all drivers to change.

- Several data-related functions now have matching versions that
  operate on an explicit buffer (e.g. crypto_apply_buf,
  crypto_contiguous_subsegment_buf, bus_dma_load_crp_buf).

- Most of the existing data-related functions operate on the input
  buffer.  However crypto_copyback always writes to the output buffer
  if a request uses a separate output buffer.

- For the regions in input/output buffers, the following conventions
  are followed:
  - AAD and IV are always present in input only and their
    fields are offsets into the input buffer.
  - payload is always present in both buffers.  If a request uses a
    separate output buffer, it must set a new crp_payload_start_output
    field to the offset of the payload in the output buffer.
  - digest is in the input buffer for verify operations, and in the
    output buffer for compute operations.  crp_digest_start is relative
    to the appropriate buffer.

- Add a crypto buffer cursor abstraction.  This is a more general form
  of some bits in the cryptosoft driver that tried to always use uio's.
  However, compared to the original code, this avoids rewalking the uio
  iovec array for requests with multiple vectors.  It also avoids
  allocate an iovec array for mbufs and populating it by instead walking
  the mbuf chain directly.

- Update the cryptosoft(4) driver to support separate output buffers
  making use of the cursor abstraction.

Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D24545
2020-05-25 22:12:04 +00:00

558 lines
12 KiB
C
Raw Blame History

/* $OpenBSD: criov.c,v 1.9 2002/01/29 15:48:29 jason Exp $ */
/*-
* Copyright (c) 1999 Theo de Raadt
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/uio.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <opencrypto/cryptodev.h>
/*
* This macro is only for avoiding code duplication, as we need to skip
* given number of bytes in the same way in three functions below.
*/
#define CUIO_SKIP() do { \
KASSERT(off >= 0, ("%s: off %d < 0", __func__, off)); \
KASSERT(len >= 0, ("%s: len %d < 0", __func__, len)); \
while (off > 0) { \
KASSERT(iol >= 0, ("%s: empty in skip", __func__)); \
if (off < iov->iov_len) \
break; \
off -= iov->iov_len; \
iol--; \
iov++; \
} \
} while (0)
static void
cuio_copydata(struct uio* uio, int off, int len, caddr_t cp)
{
struct iovec *iov = uio->uio_iov;
int iol = uio->uio_iovcnt;
unsigned count;
CUIO_SKIP();
while (len > 0) {
KASSERT(iol >= 0, ("%s: empty", __func__));
count = min(iov->iov_len - off, len);
bcopy(((caddr_t)iov->iov_base) + off, cp, count);
len -= count;
cp += count;
off = 0;
iol--;
iov++;
}
}
static void
cuio_copyback(struct uio* uio, int off, int len, c_caddr_t cp)
{
struct iovec *iov = uio->uio_iov;
int iol = uio->uio_iovcnt;
unsigned count;
CUIO_SKIP();
while (len > 0) {
KASSERT(iol >= 0, ("%s: empty", __func__));
count = min(iov->iov_len - off, len);
bcopy(cp, ((caddr_t)iov->iov_base) + off, count);
len -= count;
cp += count;
off = 0;
iol--;
iov++;
}
}
/*
* Return the index and offset of location in iovec list.
*/
static int
cuio_getptr(struct uio *uio, int loc, int *off)
{
int ind, len;
ind = 0;
while (loc >= 0 && ind < uio->uio_iovcnt) {
len = uio->uio_iov[ind].iov_len;
if (len > loc) {
*off = loc;
return (ind);
}
loc -= len;
ind++;
}
if (ind > 0 && loc == 0) {
ind--;
*off = uio->uio_iov[ind].iov_len;
return (ind);
}
return (-1);
}
void
crypto_cursor_init(struct crypto_buffer_cursor *cc,
const struct crypto_buffer *cb)
{
memset(cc, 0, sizeof(*cc));
cc->cc_type = cb->cb_type;
switch (cc->cc_type) {
case CRYPTO_BUF_CONTIG:
cc->cc_buf = cb->cb_buf;
cc->cc_buf_len = cb->cb_buf_len;
break;
case CRYPTO_BUF_MBUF:
cc->cc_mbuf = cb->cb_mbuf;
break;
case CRYPTO_BUF_UIO:
cc->cc_iov = cb->cb_uio->uio_iov;
break;
default:
#ifdef INVARIANTS
panic("%s: invalid buffer type %d", __func__, cb->cb_type);
#endif
break;
}
}
void
crypto_cursor_advance(struct crypto_buffer_cursor *cc, size_t amount)
{
size_t remain;
switch (cc->cc_type) {
case CRYPTO_BUF_CONTIG:
MPASS(cc->cc_buf_len >= amount);
cc->cc_buf += amount;
cc->cc_buf_len -= amount;
break;
case CRYPTO_BUF_MBUF:
for (;;) {
remain = cc->cc_mbuf->m_len - cc->cc_offset;
if (amount < remain) {
cc->cc_offset += amount;
break;
}
amount -= remain;
cc->cc_mbuf = cc->cc_mbuf->m_next;
cc->cc_offset = 0;
if (amount == 0)
break;
}
break;
case CRYPTO_BUF_UIO:
for (;;) {
remain = cc->cc_iov->iov_len - cc->cc_offset;
if (amount < remain) {
cc->cc_offset += amount;
break;
}
amount -= remain;
cc->cc_iov++;
cc->cc_offset = 0;
if (amount == 0)
break;
}
break;
default:
#ifdef INVARIANTS
panic("%s: invalid buffer type %d", __func__, cc->cc_type);
#endif
break;
}
}
void *
crypto_cursor_segbase(struct crypto_buffer_cursor *cc)
{
switch (cc->cc_type) {
case CRYPTO_BUF_CONTIG:
return (cc->cc_buf);
case CRYPTO_BUF_MBUF:
if (cc->cc_mbuf == NULL)
return (NULL);
KASSERT((cc->cc_mbuf->m_flags & M_EXTPG) == 0,
("%s: not supported for unmapped mbufs", __func__));
return (mtod(cc->cc_mbuf, char *) + cc->cc_offset);
case CRYPTO_BUF_UIO:
return ((char *)cc->cc_iov->iov_base + cc->cc_offset);
default:
#ifdef INVARIANTS
panic("%s: invalid buffer type %d", __func__, cc->cc_type);
#endif
return (NULL);
}
}
size_t
crypto_cursor_seglen(struct crypto_buffer_cursor *cc)
{
switch (cc->cc_type) {
case CRYPTO_BUF_CONTIG:
return (cc->cc_buf_len);
case CRYPTO_BUF_MBUF:
if (cc->cc_mbuf == NULL)
return (0);
return (cc->cc_mbuf->m_len - cc->cc_offset);
case CRYPTO_BUF_UIO:
return (cc->cc_iov->iov_len - cc->cc_offset);
default:
#ifdef INVARIANTS
panic("%s: invalid buffer type %d", __func__, cc->cc_type);
#endif
return (0);
}
}
void
crypto_cursor_copyback(struct crypto_buffer_cursor *cc, int size,
const void *vsrc)
{
size_t remain, todo;
const char *src;
char *dst;
src = vsrc;
switch (cc->cc_type) {
case CRYPTO_BUF_CONTIG:
MPASS(cc->cc_buf_len >= size);
memcpy(cc->cc_buf, src, size);
cc->cc_buf += size;
cc->cc_buf_len -= size;
break;
case CRYPTO_BUF_MBUF:
for (;;) {
KASSERT((cc->cc_mbuf->m_flags & M_EXTPG) == 0,
("%s: not supported for unmapped mbufs", __func__));
dst = mtod(cc->cc_mbuf, char *) + cc->cc_offset;
remain = cc->cc_mbuf->m_len - cc->cc_offset;
todo = MIN(remain, size);
memcpy(dst, src, todo);
dst += todo;
if (todo < remain) {
cc->cc_offset += todo;
break;
}
size -= todo;
cc->cc_mbuf = cc->cc_mbuf->m_next;
cc->cc_offset = 0;
if (size == 0)
break;
}
break;
case CRYPTO_BUF_UIO:
for (;;) {
dst = (char *)cc->cc_iov->iov_base + cc->cc_offset;
remain = cc->cc_iov->iov_len - cc->cc_offset;
todo = MIN(remain, size);
memcpy(dst, src, todo);
dst += todo;
if (todo < remain) {
cc->cc_offset += todo;
break;
}
size -= todo;
cc->cc_iov++;
cc->cc_offset = 0;
if (size == 0)
break;
}
break;
default:
#ifdef INVARIANTS
panic("%s: invalid buffer type %d", __func__, cc->cc_type);
#endif
break;
}
}
void
crypto_cursor_copydata(struct crypto_buffer_cursor *cc, int size, void *vdst)
{
size_t remain, todo;
const char *src;
char *dst;
dst = vdst;
switch (cc->cc_type) {
case CRYPTO_BUF_CONTIG:
MPASS(cc->cc_buf_len >= size);
memcpy(dst, cc->cc_buf, size);
cc->cc_buf += size;
cc->cc_buf_len -= size;
break;
case CRYPTO_BUF_MBUF:
for (;;) {
KASSERT((cc->cc_mbuf->m_flags & M_EXTPG) == 0,
("%s: not supported for unmapped mbufs", __func__));
src = mtod(cc->cc_mbuf, const char *) + cc->cc_offset;
remain = cc->cc_mbuf->m_len - cc->cc_offset;
todo = MIN(remain, size);
memcpy(dst, src, todo);
dst += todo;
if (todo < remain) {
cc->cc_offset += todo;
break;
}
size -= todo;
cc->cc_mbuf = cc->cc_mbuf->m_next;
cc->cc_offset = 0;
if (size == 0)
break;
}
break;
case CRYPTO_BUF_UIO:
for (;;) {
src = (const char *)cc->cc_iov->iov_base +
cc->cc_offset;
remain = cc->cc_iov->iov_len - cc->cc_offset;
todo = MIN(remain, size);
memcpy(dst, src, todo);
dst += todo;
if (todo < remain) {
cc->cc_offset += todo;
break;
}
size -= todo;
cc->cc_iov++;
cc->cc_offset = 0;
if (size == 0)
break;
}
break;
default:
#ifdef INVARIANTS
panic("%s: invalid buffer type %d", __func__, cc->cc_type);
#endif
break;
}
}
/*
* To avoid advancing 'cursor', make a local copy that gets advanced
* instead.
*/
void
crypto_cursor_copydata_noadv(struct crypto_buffer_cursor *cc, int size,
void *vdst)
{
struct crypto_buffer_cursor copy;
copy = *cc;
crypto_cursor_copydata(&copy, size, vdst);
}
/*
* Apply function f to the data in an iovec list starting "off" bytes from
* the beginning, continuing for "len" bytes.
*/
static int
cuio_apply(struct uio *uio, int off, int len, int (*f)(void *, void *, u_int),
void *arg)
{
struct iovec *iov = uio->uio_iov;
int iol = uio->uio_iovcnt;
unsigned count;
int rval;
CUIO_SKIP();
while (len > 0) {
KASSERT(iol >= 0, ("%s: empty", __func__));
count = min(iov->iov_len - off, len);
rval = (*f)(arg, ((caddr_t)iov->iov_base) + off, count);
if (rval)
return (rval);
len -= count;
off = 0;
iol--;
iov++;
}
return (0);
}
void
crypto_copyback(struct cryptop *crp, int off, int size, const void *src)
{
struct crypto_buffer *cb;
if (crp->crp_obuf.cb_type != CRYPTO_BUF_NONE)
cb = &crp->crp_obuf;
else
cb = &crp->crp_buf;
switch (cb->cb_type) {
case CRYPTO_BUF_MBUF:
m_copyback(cb->cb_mbuf, off, size, src);
break;
case CRYPTO_BUF_UIO:
cuio_copyback(cb->cb_uio, off, size, src);
break;
case CRYPTO_BUF_CONTIG:
MPASS(off + size <= cb->cb_buf_len);
bcopy(src, cb->cb_buf + off, size);
break;
default:
#ifdef INVARIANTS
panic("invalid crp buf type %d", cb->cb_type);
#endif
break;
}
}
void
crypto_copydata(struct cryptop *crp, int off, int size, void *dst)
{
switch (crp->crp_buf.cb_type) {
case CRYPTO_BUF_MBUF:
m_copydata(crp->crp_buf.cb_mbuf, off, size, dst);
break;
case CRYPTO_BUF_UIO:
cuio_copydata(crp->crp_buf.cb_uio, off, size, dst);
break;
case CRYPTO_BUF_CONTIG:
MPASS(off + size <= crp->crp_buf.cb_buf_len);
bcopy(crp->crp_buf.cb_buf + off, dst, size);
break;
default:
#ifdef INVARIANTS
panic("invalid crp buf type %d", crp->crp_buf.cb_type);
#endif
break;
}
}
int
crypto_apply_buf(struct crypto_buffer *cb, int off, int len,
int (*f)(void *, void *, u_int), void *arg)
{
int error;
switch (cb->cb_type) {
case CRYPTO_BUF_MBUF:
error = m_apply(cb->cb_mbuf, off, len, f, arg);
break;
case CRYPTO_BUF_UIO:
error = cuio_apply(cb->cb_uio, off, len, f, arg);
break;
case CRYPTO_BUF_CONTIG:
MPASS(off + len <= cb->cb_buf_len);
error = (*f)(arg, cb->cb_buf + off, len);
break;
default:
#ifdef INVARIANTS
panic("invalid crypto buf type %d", cb->cb_type);
#endif
error = 0;
break;
}
return (error);
}
int
crypto_apply(struct cryptop *crp, int off, int len,
int (*f)(void *, void *, u_int), void *arg)
{
return (crypto_apply_buf(&crp->crp_buf, off, len, f, arg));
}
static inline void *
m_contiguous_subsegment(struct mbuf *m, size_t skip, size_t len)
{
int rel_off;
MPASS(skip <= INT_MAX);
m = m_getptr(m, (int)skip, &rel_off);
if (m == NULL)
return (NULL);
MPASS(rel_off >= 0);
skip = rel_off;
if (skip + len > m->m_len)
return (NULL);
return (mtod(m, char*) + skip);
}
static inline void *
cuio_contiguous_segment(struct uio *uio, size_t skip, size_t len)
{
int rel_off, idx;
MPASS(skip <= INT_MAX);
idx = cuio_getptr(uio, (int)skip, &rel_off);
if (idx < 0)
return (NULL);
MPASS(rel_off >= 0);
skip = rel_off;
if (skip + len > uio->uio_iov[idx].iov_len)
return (NULL);
return ((char *)uio->uio_iov[idx].iov_base + skip);
}
void *
crypto_buffer_contiguous_subsegment(struct crypto_buffer *cb, size_t skip,
size_t len)
{
switch (cb->cb_type) {
case CRYPTO_BUF_MBUF:
return (m_contiguous_subsegment(cb->cb_mbuf, skip, len));
case CRYPTO_BUF_UIO:
return (cuio_contiguous_segment(cb->cb_uio, skip, len));
case CRYPTO_BUF_CONTIG:
MPASS(skip + len <= cb->cb_buf_len);
return (cb->cb_buf + skip);
default:
#ifdef INVARIANTS
panic("invalid crp buf type %d", cb->cb_type);
#endif
return (NULL);
}
}
void *
crypto_contiguous_subsegment(struct cryptop *crp, size_t skip, size_t len)
{
return (crypto_buffer_contiguous_subsegment(&crp->crp_buf, skip, len));
}
Reference in New Issue View Git Blame Copy Permalink