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manual pages for the new kernel crypto support (need work)

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Sam Leffler 2002-10-04 20:43:30 +00:00
parent 8b7ce2ff52
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3
share/man/man4/Makefile
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@ -28,6 +28,7 @@ MAN= aac.4 \
ccd.4 \
cd.4 \
ch.4 \
crypto.4 \
csa.4 \
cue.4 \
da.4 \
@ -51,6 +52,7 @@ MAN= aac.4 \
gre.4 \
gusc.4 \
gx.4 \
hifn.4 \
ichsmb.4 \
icmp.4 \
icmp6.4 \
@ -185,6 +187,7 @@ MAN= aac.4 \
tun.4 \
twe.4 \
txp.4 \
ubsec.4 \
ucom.4 \
udbp.4 \
udp.4 \

113
share/man/man4/crypto.4 Normal file
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@ -0,0 +1,113 @@
.\" $OpenBSD: crypto.4,v 1.4 2002/09/12 07:15:03 deraadt Exp $
.\" $FreeBSD$
.\"
.\" Copyright (c) 2001 Theo de Raadt
.\" All rights reserved.
.\"
.\" 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.
.\"
.Dd October 3, 2002
.Dt CRYPTO 4
.Os
.Sh NAME
.Nm crypto
.Nd hardware crypto access driver
.Sh SYNOPSIS
.Nm device crypto
.Sh DESCRIPTION
The
.Nm
driver provides userland applications access to hardware crypto support
via the kernel.
The
.Pa /dev/crypto
device node primarily operates in an
.Xr ioctl 2
based model, permitting a variety of applications to query device capabilities,
submit transactions, and get results.
.Pp
If
.Ar count
given in the specification, and is greater than 0, a maximum of one
.Nm crypto
device is created.
.Pp
The following
.Xr ioctl 2
calls apply only to the
.Nm crypto
devices:
.Bl -tag -width CIOCGSESSION
.It Dv CIOCGSESSION
Setup a new crypto session for a new type of operation.
.It Dv CIOCFSESSION
Free a previously established session.
.It Dv CIOCCRYPT
Perform a crypto operation against a previously setup session.
.El
.Pp
.Sh FEATURES
Depending on hardware being present, the following symmetric and
assymetric cryptographic features are potentially available from
.Pa /dev/crypto :
.Pp
.Bl -tag -compact -width CRYPTO_RIPEMD160_HMAC -offset indent
.It CRYPTO_DES_CBC
.It CRYPTO_3DES_CBC
.It CRYPTO_BLF_CBC
.It CRYPTO_CAST_CBC
.It CRYPTO_SKIPJACK_CBC
.It CRYPTO_MD5_HMAC
.It CRYPTO_SHA1_HMAC
.It CRYPTO_RIPEMD160_HMAC
.It CRYPTO_MD5_KPDK
.It CRYPTO_SHA1_KPDK
.It CRYPTO_AES_CBC
.It CRYPTO_ARC4
.It CRYPTO_MD5
.It CRYPTO_SHA1
.It CRK_MOD_EXP
.It CRK_MOD_EXP_CRT
.It CRK_DSA_SIGN
.It CRK_DSA_VERIFY
.It CRK_DH_COMPUTE_KEY
.El
.Pp
.Sh FILES
.Bl -tag -width /dev/crypto -compact
.It Pa /dev/crypto
crypto access device
.El
.Sh SEE ALSO
.Xr hifn 4 ,
.Xr ubsec 4 ,
.Xr crypto 9
.Sh HISTORY
The
.Nm
driver first appeared in
OpenBSD 3.0.
The
.Nm
driver was imported to FreeBSD in 5.0.

111
share/man/man4/hifn.4 Normal file
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@ -0,0 +1,111 @@
.\" $OpenBSD: hifn.4,v 1.32 2002/09/26 07:55:40 miod Exp $
.\" $FreeBSD$
.\"
.\" Copyright (c) 2000 Theo de Raadt
.\" All rights reserved.
.\"
.\" 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.
.\"
.Dd October 3, 2002
.Dt HIFN 4
.Os
.Sh NAME
.Nm hifn
.Nd Hifn 7751/7951/7811 crypto accelerator
.Sh SYNOPSIS
.Nm device hifn
.Sh DESCRIPTION
The
.Nm
driver supports various cards containing the Hifn 7751, Hifn 7951, or
Hifn 7811
chipsets, such as
.Bl -tag -width namenamenamena -offset indent
.It Invertex AEON
No longer being made.
Came as 128KB SRAM model, or 2MB DRAM model.
.It Hifn 7751
Reference board with 512KB SRAM.
.It PowerCrypt
See
.Pa http://www.powercrypt.com/ .
Comes with 512KB SRAM.
.It XL-Crypt
See
.Pa http://www.powercrypt.com/ .
Only board based on 7811 (which is faster than 7751 and has
a random number generator).
.It NetSec 7751
See
.Pa http://www.netsec.net/ .
Supports the most IPsec sessions, with 1MB SRAM.
.It Soekris Engineering vpn1201 and vpn1211
See
.Pa http://www.soekris.com/ .
Contains a 7951 and supports symmetric and random number operations.
.El
.Pp
The
.Nm
driver registers itself to accelerate DES, Triple-DES, ARC4, MD5,
MD5-HMAC, SHA1, and SHA1-HMAC operations for
.Xr ipsec 4
and
.Xr crypto 4 .
.Pp
The
.Tn Hifn 7951
and
.Tn Hifn 7811
will also supply data to the kernel
.Xr random 4
subsystem.
.Sh BUGS
The 7751 chip starts out at initialization by only supporting compression.
A proprietary algorithm, which has been reverse engineered, is required to
unlock the cryptographic functionality of the chip.
It is possible for vendors to make boards which have a lock ID not known
to the driver, but all vendors currently just use the obvious ID which is
13 bytes of 0.
.Sh SEE ALSO
.Xr crypt 3 ,
.Xr crypto 4 ,
.Xr intro 4 ,
.Xr ipsec 4 ,
.Xr random 4 ,
.Xr crypto 9
.Sh CAVEATS
The Hifn 9751 shares the same PCI id.
This chip is basically a 7751, but with the cryptographic functions missing.
Instead, the 9751 is only capable of doing compression.
Since we do not currently attempt to use any of these chips to do
compression, the 9751-based cards are not useful.
.Sh HISTORY
The
.Nm
device driver appeared in
OpenBSD 2.7.
The
.Nm
device driver was imported to FreeBSD in 5.0.

99
share/man/man4/ubsec.4 Normal file
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@ -0,0 +1,99 @@
.\" $OpenBSD: ubsec.4,v 1.18 2002/09/26 07:55:41 miod Exp $
.\" $FreeBSD$
.\"
.\" Copyright (c) 2000 Jason L. Wright (jason@thought.net)
.\" All rights reserved.
.\"
.\" 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. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by Jason L. Wright
.\" 4. 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.
.\"
.Dd October 3, 2002
.Dt UBSEC 4
.Os
.Sh NAME
.Nm ubsec
.Nd Broadcom and BlueSteel uBsec 5x0x crypto accelerator
.Sh SYNOPSIS
.Nm device ubsec
.Sh DESCRIPTION
The
.Nm
driver supports cards containing any of the following chips:
.Bl -tag -width "Broadcom BCM5821" -offset indent
.It Bluesteel 5501
The original chipset, no longer made. This extremely rare unit
was not very fast, lacked a RNG, and had a number of other bugs.
.It Bluesteel 5601
A faster and fixed version of the original, with a random number
unit and large number engine added.
.It Broadcom BCM5801
A BCM5805 without public key engine or random number generator.
.It Broadcom BCM5802
A slower version of the BCM5805.
.It Broadcom BCM5805
Faster version of Bluesteel 5601.
.It Broadcom BCM5820
64 bit version of the chip, and significantly more advanced.
.It Broadcom BCM5821
Faster version of the BCM5820.
.It Broadcom BCM5822
Faster version of the BCM5820.
.El
.Pp
The
.Nm
driver registers itself to accelerate DES, Triple-DES, MD5-HMAC,
and SHA1-HMAC operations for
.Xr ipsec 4
and
.Xr crypto 4 .
.Pp
On those models which contain a public key engine (almost all of the
more recent ones), this feature is registered with the
.Xr crypto 4
subsystem.
.Pp
On all models except the Bluesteel 5501 and Broadcom 5801, the driver
registers itself to provide random data to the
.Xr random 4
subsystem.
.Sh SEE ALSO
.Xr crypt 3 ,
.Xr crypto 4 ,
.Xr intro 4 ,
.Xr ipsec 4 ,
.Xr random 4 ,
.Xr crypto 9
.Sh HISTORY
The
.Nm
device driver appeared in
OpenBSD 2.8.
The
.Nm
device driver was imported to FreeBSD in 5.0.
.Sh BUGS
The BCM5801 and BCM5802 have not actually been tested.

2
share/man/man9/Makefile
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@ -27,7 +27,7 @@ MAN= BUF_LOCK.9 BUF_LOCKFREE.9 BUF_LOCKINIT.9 BUF_REFCNT.9 \
bus_generic_shutdown.9 bus_release_resource.9 \
byteorder.9 \
cd.9 cdevsw_add.9 cdevsw_remove.9 condvar.9 copy.9 \
critical_enter.9 \
critical_enter.9 crypto.9 \
devclass.9 devclass_add_driver.9 devclass_find.9 \
devclass_get_device.9 devclass_get_devices.9 \
devclass_get_maxunit.9 devclass_get_name.9 devclass_get_softc.9 \

591
share/man/man9/crypto.9 Normal file
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@ -0,0 +1,591 @@
.\" $OpenBSD: crypto.9,v 1.19 2002/07/16 06:31:57 angelos Exp $
.\" $FreeBSD$
.\"
.\" The author of this man page is Angelos D. Keromytis (angelos@cis.upenn.edu)
.\"
.\" Copyright (c) 2000, 2001 Angelos D. Keromytis
.\"
.\" Permission to use, copy, and modify this software with or without fee
.\" is hereby granted, provided that this entire notice is included in
.\" all source code copies of any software which is or includes a copy or
.\" modification of this software.
.\"
.\" THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
.\" IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
.\" REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
.\" MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
.\" PURPOSE.
.\"
.Dd October 3, 2002
.Dt CRYPTO 9
.Os
.Sh NAME
.Nm crypto
.Nd API for cryptographic services in the kernel
.Sh SYNOPSIS
.Fd #include <crypto/cryptodev.h>
.Ft int32_t
.Fn crypto_get_driverid "u_int8_t"
.Ft int
.Fn crypto_register "u_int32_t" "int" "u_int16_t" "u_int32_t" "int (*)(u_int32_t *, struct cryptoini *)" "int (*)(u_int64_t)" "int (*)(struct cryptop *)"
.Ft int
.Fn crypto_kregister "u_int32_t" "int" "u_int32_t" "int (*)(struct cryptkop *)"
.Ft int
.Fn crypto_unregister "u_int32_t" "int"
.Ft void
.Fn crypto_done "struct cryptop *"
.Ft void
.Fn crypto_kdone "struct cryptkop *"
.Ft int
.Fn crypto_newsession "u_int64_t *" "struct cryptoini *" "int"
.Ft int
.Fn crypto_freesession "u_int64_t"
.Ft int
.Fn crypto_dispatch "struct cryptop *"
.Ft int
.Fn crypto_kdispatch "struct cryptkop *"
.Ft struct cryptop *
.Fn crypto_getreq "int"
.Ft void
.Fn crypto_freereq "void"
.Bd -literal
#define EALG_MAX_BLOCK_LEN 16
struct cryptoini {
int cri_alg;
int cri_klen;
int cri_rnd;
caddr_t cri_key;
u_int8_t cri_iv[EALG_MAX_BLOCK_LEN];
struct cryptoini *cri_next;
};
struct cryptodesc {
int crd_skip;
int crd_len;
int crd_inject;
int crd_flags;
struct cryptoini CRD_INI;
struct cryptodesc *crd_next;
};
struct cryptop {
u_int64_t crp_sid;
int crp_ilen;
int crp_olen;
int crp_alloctype;
int crp_etype;
int crp_flags;
caddr_t crp_buf;
caddr_t crp_opaque;
struct cryptodesc *crp_desc;
int (*crp_callback) (struct cryptop *);
struct cryptop *crp_next;
caddr_t crp_mac;
};
struct crparam {
caddr_t crp_p;
u_int crp_nbits;
};
#define CRK_MAXPARAM 8
struct cryptkop {
u_int krp_op; /* ie. CRK_MOD_EXP or other */
u_int krp_status; /* return status */
u_short krp_iparams; /* # of input parameters */
u_short krp_oparams; /* # of output parameters */
u_int krp_pad1;
struct crparam krp_param[CRK_MAXPARAM];
struct crparam krp_kvp[CRK_MAXPARAM];
u_int32_t krp_hid;
int (*krp_callback)(struct cryptkop *);
struct cryptkop *krp_next;
};
.Ed
.br
.Sh DESCRIPTION
.Nm
is a framework for drivers of cryptographic hardware to register with
the kernel so
.Dq consumers
(other kernel subsystems, and eventually
users through an appropriate device) are able to make use of it.
Drivers register with the framework the algorithms they support,
and provide entry points (functions) the framework may call to
establish, use, and tear down sessions.
Sessions are used to cache cryptographic information in a particular driver
(or associated hardware), so initialization is not needed with every request.
Consumers of cryptographic services pass a set of
descriptors that instruct the framework (and the drivers registered
with it) of the operations that should be applied on the data (more
than one cryptographic operation can be requested).
.Pp
Keying operations are supported as well.
Unlike the symmetric operators described above,
these sessionless commands perform mathematical operations using
input and output parameters.
.Pp
Since the consumers may not be associated with a process, drivers may
not use
.Xr tsleep 9 .
The same holds for the framework.
Thus, a callback mechanism is used
to notify a consumer that a request has been completed (the
callback is specified by the consumer on an per-request basis).
The callback is invoked by the framework whether the request was
successfully completed or not.
An error indication is provided in the latter case.
A specific error code,
.Er EAGAIN ,
is used to indicate that a session number has changed and that the
request may be re-submitted immediately with the new session number.
Errors are only returned to the invoking function if not
enough information to call the callback is available (meaning, there
was a fatal error in verifying the arguments).
For session initialization and teardown there is no callback mechanism used.
.br
.Pp
The
.Fn crypto_newsession
routine is called by consumers of cryptographic services (such as the
.Xr ipsec 4
stack) that wish to establish a new session with the framework.
On success, the first argument will contain the Session Identifier (SID).
The second argument contains all the necessary information for
the driver to establish the session.
The third argument indicates whether a
hardware driver (1) should be used or not (0).
The various fields in the
.Fa cryptoini
structure are:
.Bl -tag -width foobarmoocow
.It Fa cri_alg
Contains an algorithm identifier.
Currently supported algorithms are:
.Bd -literal
CRYPTO_DES_CBC
CRYPTO_3DES_CBC
CRYPTO_BLF_CBC
CRYPTO_CAST_CBC
CRYPTO_SKIPJACK_CBC
CRYPTO_MD5_HMAC
CRYPTO_SHA1_HMAC
CRYPTO_RIPEMD160_HMAC
CRYPTO_MD5_KPDK
CRYPTO_SHA1_KPDK
CRYPTO_AES_CBC
CRYPTO_ARC4
CRYPTO_MD5
CRYPTO_SHA1
.Ed
.Pp
.It Fa cri_klen
Specifies the length of the key in bits, for variable-size key
algorithms.
.It Fa cri_rnd
Specifies the number of rounds to be used with the algorithm, for
variable-round algorithms.
.It Fa cri_key
Contains the key to be used with the algorithm.
.It Fa cri_iv
Contains an explicit initialization vector (IV), if it does not prefix
the data.
This field is ignored during initialization.
If no IV is explicitly passed (see below on details), a random IV is used
by the device driver processing the request.
.It Fa cri_next
Contains a pointer to another
.Fa cryptoini
structure.
Multiple such structures may be linked to establish multi-algorithm sessions
.Pf ( Xr ipsec 4
is an example consumer of such a feature).
.El
.Pp
The
.Fa cryptoini
structure and its contents will not be modified by the framework (or
the drivers used).
Subsequent requests for processing that use the
SID returned will avoid the cost of re-initializing the hardware (in
essence, SID acts as an index in the session cache of the driver).
.Pp
.Fn crypto_freesession
is called with the SID returned by
.Fn crypto_newsession
to disestablish the session.
.Pp
.Fn crypto_dispatch
is called to process a request.
The various fields in the
.Fa cryptop
structure are:
.Bl -tag -width crp_alloctype
.It Fa crp_sid
Contains the SID.
.It Fa crp_ilen
Indicates the total length in bytes of the buffer to be processed.
.It Fa crp_olen
On return, contains the total length of the result.
For symmetric crypto operations, this will be the same as the input length.
.It Fa crp_alloctype
Indicates the type of buffer, as used in the kernel
.Xr malloc 9
routine.
This will be used if the framework needs to allocate a new
buffer for the result (or for re-formatting the input).
.It Fa crp_callback
This routine is invoked upon completion of the request, whether
successful or not.
It is invoked through the
.Fn crypto_done
routine.
If the request was not successful, an error code is set in the
.Fa crp_etype
field.
It is the responsibility of the callback routine to set the appropriate
.Xr spl 9
level.
.It Fa crp_etype
Contains the error type, if any errors were encountered, or zero if
the request was successfully processed.
If the
.Er EAGAIN
error code is returned, the SID has changed (and has been recorded in the
.Fa crp_sid
field).
The consumer should record the new SID and use it in all subsequent requests.
In this case, the request may be re-submitted immediately.
This mechanism is used by the framework to perform
session migration (move a session from one driver to another, because
of availability, performance, or other considerations).
.Pp
Note that this field only makes sense when examined by
the callback routine specified in
.Fa crp_callback .
Errors are returned to the invoker of
.Fn crypto_process
only when enough information is not present to call the callback
routine (i.e., if the pointer passed is
.Dv NULL
or if no callback routine was specified).
.It Fa crp_flags
Is a bitmask of flags associated with this request.
Currently defined flags are:
.Bl -tag -width CRYPTO_F_IMBUF
.It Dv CRYPTO_F_IMBUF
The buffer pointed to by
.Fa crp_buf
is an mbuf chain.
.El
.Pp
.It Fa crp_buf
Points to the input buffer.
On return (when the callback is invoked),
it contains the result of the request.
The input buffer may be an mbuf
chain or a contiguous buffer (of a type identified by
.Fa crp_alloctype ) ,
depending on
.Fa crp_flags .
.It Fa crp_opaque
This is passed through the crypto framework untouched and is
intended for the invoking application's use.
.It Fa crp_desc
This is a linked list of descriptors.
Each descriptor provides
information about what type of cryptographic operation should be done
on the input buffer.
The various fields are:
.Bl -tag -width=crd_inject
.It Fa crd_skip
The offset in the input buffer where processing should start.
.It Fa crd_len
How many bytes, after
.Fa Fa crd_skip ,
should be processed.
.It Fa crd_inject
Offset from the beginning of the buffer to insert any results.
For encryption algorithms, this is where the initialization vector
(IV) will be inserted when encrypting or where it can be found when
decrypting (subject to
.Fa Fa crd_flags ) .
For MAC algorithms, this is where the result of the keyed hash will be
inserted.
.It Fa crd_flags
The following flags are defined:
.Bl -tag -width CRD_F_IV_EXPLICIT
.It Dv CRD_F_ENCRYPT
For encryption algorithms, this bit is set when encryption is required
(when not set, decryption is performed).
.It Dv CRD_F_IV_PRESENT
For encryption algorithms, this bit is set when the IV already
precedes the data, so the
.Fa crd_inject
value will be ignored and no IV will be written in the buffer.
Otherwise, the IV used to encrypt the packet will be written
at the location pointed to by
.Fa crd_inject .
The IV length is assumed to be equal to the blocksize of the
encryption algorithm.
Some applications that do special
.Dq IV cooking ,
such as the half-IV mode in
.Xr ipsec 4 ,
can use this flag to indicate that the IV should not be written on the packet.
This flag is typically used in conjunction with the
.Dv CRD_F_IV_EXPLICIT
flag.
.It Dv CRD_F_IV_EXPLICIT
For encryption algorithms, this bit is set when the IV is explicitly
provided by the consumer in the
.Fa crd_iv
fields.
Otherwise, for encryption operations the IV is provided for by
the driver used to perform the operation, whereas for decryption
operations it is pointed to by the
.Fa crd_inject
field.
This flag is typically used when the IV is calculated
.Dq on the fly
by the consumer, and does not precede the data (some
.Xr ipsec 4
configurations, and the encrypted swap are two such examples).
.It Dv CRD_F_COMP
For compression algorithms, this bit is set when compression is required (when
not set, decompression is performed).
.El
.It Fa CRD_INI
This
.Fa cryptoini
structure will not be modified by the framework or the device drivers.
Since this information accompanies every cryptographic
operation request, drivers may re-initialize state on-demand
(typically an expensive operation).
Furthermore, the cryptographic
framework may re-route requests as a result of full queues or hardware
failure, as described above.
.It Fa crd_next
Point to the next descriptor.
Linked operations are useful in protocols such as
.Xr ipsec 4 ,
where multiple cryptographic transforms may be applied on the same
block of data.
.El
.El
.Pp
.Fn crypto_getreq
allocates a
.Fa cryptop
structure with a linked list of as many
.Fa cryptodesc
structures as were specified in the argument passed to it.
.Pp
.Fn crypto_freereq
deallocates a structure
.Fa cryptop
and any
.Fa cryptodesc
structures linked to it.
Note that it is the responsibility of the
callback routine to do the necessary cleanups associated with the
opaque field in the
.Fa cryptop
structure.
.Pp
.Fn crypto_kdispatch
is called to perform a keying operation.
The various fields in the
.Fa crytokop
structure are:
.Bl -tag -width crp_alloctype
.It Fa krp_op
Operation code, such as CRK_MOD_EXP.
.It Fa krp_status
Return code.
This errno-style variable indicates whether lower level reasons
for operation failure.
.It Fa krp_iparams
Number if input parameters to the specified operation.
Note that each operation has a (typically hardwired) number of such parameters.
.It Fa krp_oparams
Number if output parameters from the specified operation.
Note that each operation has a (typically hardwired) number of such parameters.
.It Fa krp_kvp
An array of kernel memory blocks containing the parameters.
.It Fa krp_hid
Identifier specifying which low-level driver is being used.
.It Fa krp_callback
Callback called on completion of a keying operation.
.El
.Sh DRIVER-SIDE API
The
.Fn crypto_get_driverid ,
.Fn crypto_register ,
.Fn crypto_kregister ,
.Fn crypto_unregister ,
and
.Fn crypto_done
routines are used by drivers that provide support for cryptographic
primitives to register and unregister with the kernel crypto services
framework.
Drivers must first use the
.Fn crypto_get_driverid
function to acquire a driver identifier, specifying the
.Fa cc_flags
as an argument (normally 0, but software-only drivers should specify
.Dv CRYPTOCAP_F_SOFTWARE Ns ).
For each algorithm the driver supports, it must then call
.Fn crypto_register .
The first two arguments are the driver and algorithm identifiers.
The next two arguments specify the largest possible operator length (in bits,
important for public key operations) and flags (e.g., whether an hardware RNG is
available) for this algorithm.
The last three arguments must be provided in the first call to
.Fn crypto_register
and are ignored in all subsequent calls.
They are pointers to three
driver-provided functions that the framework may call to establish new
cryptographic context with the driver, free already established
context, and ask for a request to be processed (encrypt, decrypt,
etc.)
.Fn crypto_unregister
is called by drivers that wish to withdraw support for an algorithm.
The two arguments are the driver and algorithm identifiers, respectively.
Typically, drivers for
.Xr pcmcia 4
crypto cards that are being ejected will invoke this routine for all
algorithms supported by the card.
If called with
.Dv CRYPTO_ALGORITHM_ALL ,
all algorithms registered for a driver will be unregistered in one go
and the driver will be disabled (no new sessions will be allocated on
that driver, and any existing sessions will be migrated to other
drivers).
The same will be done if all algorithms associated with a driver are
unregistered one by one.
.Pp
The calling convention for the three driver-supplied routines is:
.Bd -literal
int (*newsession) (u_int32_t *, struct cryptoini *);
int (*freesession) (u_int64_t);
int (*process) (struct cryptop *);
int (*kprocess) (struct cryptkop *);
.Ed
.Pp
On invocation, the first argument to
.Fn newsession
contains the driver identifier obtained via
.Fn crypto_get_driverid .
On successfully returning, it should contain a driver-specific session
identifier.
The second argument is identical to that of
.Fn crypto_newsession .
.Pp
The
.Fn freesession
routine takes as argument the SID (which is the concatenation of the
driver identifier and the driver-specific session identifier).
It should clear any context associated with the session (clear hardware
registers, memory, etc.).
.Pp
The
.Fn process
routine is invoked with a request to perform crypto processing.
This routine must not block, but should queue the request and return
immediately.
Upon processing the request, the callback routine should be invoked.
In case of error, the error indication must be placed in the
.Fa crp_etype
field of the
.Fa cryptop
structure.
When the request is completed, or an error is detected, the
.Fn process
routine should invoked
.Fn crypto_done .
Session migration may be performed, as mentioned previously.
.Pp
The
.Fn kprocess
routine is invoked with a request to perform crypto key processing.
This routine must not block, but should queue the request and return
immediately.
Upon processing the request, the callback routine should be invoked.
In case of error, the error indication must be placed in the
.Fa krp_status
field of the
.Fa cryptkop
structure.
When the request is completed, or an error is detected, the
.Fn kprocess
routine should invoked
.Fn crypto_kdone .
.Sh RETURN VALUES
.Fn crypto_register ,
.Fn crypto_kregister ,
.Fn crypto_unregister ,
.Fn crypto_newsession ,
and
.Fn crypto_freesession
return 0 on success, or an error code on failure.
.Fn crypto_get_driverid
returns a non-negative value on error, and \-1 on failure.
.Fn crypto_getreq
returns a pointer to a
.Fa cryptop
structure and
.Dv NULL
on failure.
.Fn crypto_dispatch
returns
.Er EINVAL
is its argument or the callback function was
.Dv NULL ,
and 0 otherwise.
The callback is provided with an error code in case of failure, in the
.Fa crp_etype
field.
.Sh FILES
.Bl -tag -width sys/crypto/crypto.c
.It Pa sys/crypto/crypto.c
most of the framework code
.El
.Sh SEE ALSO
.Xr ipsec 4 ,
.Xr pcmcia 4 ,
.Xr malloc 9 ,
.Xr tsleep 9
.Sh HISTORY
The cryptographic framework first appeared in
OpenBSD 2.7
and was written by Angelos D. Keromytis <angelos@openbsd.org>.
.Sh BUGS
The framework currently assumes that all the algorithms in a
.Fn crypto_newsession
operation must be available by the same driver.
If that's not the case, session initialization will fail.
.Pp
The framework also needs a mechanism for determining which driver is
best for a specific set of algorithms associated with a session.
Some type of benchmarking is in order here.
.Pp
Multiple instances of the same algorithm in the same session are not
supported.
Note that 3DES is considered one algorithm (and not three
instances of DES).
Thus, 3DES and DES could be mixed in the same request.
.Pp
A queue for completed operations should be implemented and processed
at some software
.Xr spl 9
level, to avoid overall system latency issues, and potential kernel
stack exhaustion while processing a callback.
.Pp
When SMP time comes, we will support use of a second processor (or
more) as a crypto device (this is actually AMP, but we need the same
basic support).