This is actually a local DoS, as every user can use /dev/crypto if there
is crypto hardware in the system and cryptodev.ko is loaded (or compiled
into the kernel).
Reported by: Mike Tancsa <mike@sentex.net>
MFC after: 1 day
It checked other algorithms against this bug and it seems they aren't
affected.
Reported by: Mike Tancsa <mike@sentex.net>
PR: i386/84860
Reviewed by: phk, cperciva(x2)
Don't grab Giant in the upper syscall/wrapper code
NET_LOCK_GIANT in the socket code (sockets/fifos).
mtx_lock(&Giant) in the vnode code.
mtx_lock(&Giant) in the opencrypto code. (This may actually not be
needed, but better safe than sorry).
Devfs grabs Giant if the driver is marked as needing Giant.
individual file object implementations can optionally acquire Giant if
they require it:
- soo_close(): depends on debug.mpsafenet
- pipe_close(): Giant not acquired
- kqueue_close(): Giant required
- vn_close(): Giant required
- cryptof_close(): Giant required (conservative)
Notes:
Giant is still acquired in close() even when closing MPSAFE objects
due to kqueue requiring Giant in the calling closef() code.
Microbenchmarks indicate that this removal of Giant cuts 3%-3% off
of pipe create/destroy pairs from user space with SMP compiled into
the kernel.
The cryptodev and opencrypto code appears MPSAFE, but I'm unable to
test it extensively and so have left Giant over fo_close(). It can
probably be removed given some testing and review.
Introduce d_version field in struct cdevsw, this must always be
initialized to D_VERSION.
Flip sense of D_NOGIANT flag to D_NEEDGIANT, this involves removing
four D_NOGIANT flags and adding 145 D_NEEDGIANT flags.
table, acquiring the necessary locks as it works. It usually returns
two references to the new descriptor: one in the descriptor table
and one via a pointer argument.
As falloc releases the FILEDESC lock before returning, there is a
potential for a process to close the reference in the file descriptor
table before falloc's caller gets to use the file. I don't think this
can happen in practice at the moment, because Giant indirectly protects
closes.
To stop the file being completly closed in this situation, this change
makes falloc set the refcount to two when both references are returned.
This makes life easier for several of falloc's callers, because the
first thing they previously did was grab an extra reference on the
file.
Reviewed by: iedowse
Idea run past: jhb
provide no methods does not make any sense, and is not used by any
driver.
It is a pretty hard to come up with even a theoretical concept of
a device driver which would always fail open and close with ENODEV.
Change the defaults to be nullopen() and nullclose() which simply
does nothing.
Remove explicit initializations to these from the drivers which
already used them.
software crypto device:
o record crypto device capabilities in each session id
o add a capability that indicates if the crypto driver operates synchronously
o tag the software crypto driver as operating synchronously
This commit also introduces crypto session id macros that cleanup their
construction and querying.
o add a ``done'' flag for crypto operations; this is set when the operation
completes and is intended for callers to check operations that may complete
``prematurely'' because of direct callbacks
o close a race for operations where the crypto driver returns ERESTART: we
need to hold the q lock to insure the blocked state for the driver and any
driver-private state is consistent; otherwise drivers may take an interrupt
and notify the crypto subsystem that it can unblock the driver but operations
will be left queued and never be processed
o close a race in /dev/crypto where operations can complete before the caller
can sleep waiting for the callback: use a per-session mutex and the new done
flag to handle this
o correct crypto_dispatch's handling of operations where the driver returns
ERESTART: the return value must be zero and not ERESTART, otherwise the
caller may free the crypto request despite it being queued for later handling
(this typically results in a later panic)
o change crypto mutex ``names'' so witness printouts and the like are more
meaningful
branches:
Initialize struct cdevsw using C99 sparse initializtion and remove
all initializations to default values.
This patch is automatically generated and has been tested by compiling
LINT with all the fields in struct cdevsw in reverse order on alpha,
sparc64 and i386.
Approved by: re(scottl)
should be done in crypto_done rather than in the callback thread
o use this flag to mark operations from /dev/crypto since the callback
routine just does a wakeup; this eliminates the last unneeded ctx switch
o change CRYPTO_F_NODELAY to CRYPTO_F_BATCH with an inverted meaning
so "0" becomes the default/desired setting (needed for user-mode
compatibility with openbsd)
o change crypto_dispatch to honor CRYPTO_F_BATCH instead of always
dispatching immediately
o remove uses of CRYPTO_F_NODELAY
o define COP_F_BATCH for ops submitted through /dev/crypto and pass
this on to the op that is submitted
Similar changes and more eventually coming for asymmetric ops.
MFC if re gives approval.
pointer types, and remove a huge number of casts from code using it.
Change struct xfile xf_data to xun_data (ABI is still compatible).
If we need to add a #define for f_data and xf_data we can, but I don't
think it will be necessary. There are no operational changes in this
commit.
or crypto_kdispatch unless the driver is currently blocked. This eliminates
the context switch to the dispatch thread for virtually all requests.
Note that this change means that for software crypto drivers the caller
will now block until the request is completed and the callback is dispatched
to the callback thread (h/w drivers will typically just dispatch the op to
the device and return quickly). If this is an issue we can either implement
a non-blocking interface in the s/w crypto driver or use either the
"no delay" flag in the crypto request or the "software driver" capability
flag to control what to do.
Sponsored by: Vernier Networks
cryptodev or kldunload cryptodev module); crypto statistcs; remove
unused alloctype field from crypto op to offset addition of the
performance time stamp
Supported by: Vernier Networks
for processing callbacks. This closes race conditions caused by locking
too many things with a single mutex.
o reclaim crypto requests under certain (impossible) failure conditions
a consistent interface to h/w and s/w crypto algorithms for use by the
kernel and (for h/w at least) by user-mode apps. Access for user-level
code is through a /dev/crypto device that'll eventually be used by openssl
to (potentially) accelerate many applications. Coming soon is an IPsec
that makes use of this service to accelerate ESP, AH, and IPCOMP protocols.
Included here is the "core" crypto support, /dev/crypto driver, various
crypto algorithms that are not already present in the KAME crypto area,
and support routines used by crypto device drivers.
Obtained from: openbsd