I'll give you two pieces of advice that almost everyone on the list won't
agree with :)
1) Make a static openssl and static stunnel and locate them someplace apart
from the standard locations (/usr/local/company_name/lib is what I use).
This means if anyone messes with openssl or stunnel you won't be affected -
and it will always work as it is static - and part of your application - the
user does not even need your libraries. I have a personal distaste for
dynamic linking . mostly because I have a lot of customers that update a lot
of things (including openssl - a lot - and stunnel sometimes) . and then
wonder why things stop working. A 10 year old openssl and stunnel - all
static - will still run and work fine past all updates and user messing
around. I choose when I want to update openssl and stunnel (meaning I look
to see if there is something new I need or want). As a result I missed the
keep alive and poodle bugs - I did not update until after both were fixed.
2) Forget hardware implementation - geez - modern computers are so darn fast
that I cannot imagine you really need that level of "speed up" versus the
grief you are handling. I have customers that exchange millions (4+) XML
documents a day, all through stunnel, all through inetd (also not efficient
supposedly - just reliable and always works and needs no management) - and
have no problems. I am using IBM p Series (AIX) and these machines even at
the low level are fast . but I also use some SCO and Linux and certainly
with lesser volume they are fine as well.
3) OK - 3 is really - use inetd, so much easier and always works (assuming
you have Unix). If inetd crashes Unix crashes so . see number 2 for reasons
:)
Of course, these ideas won't help much if you don't have a Unix variation or
if you are really that tight on performance (although if you are I'd suggest
hardware upgrades!).
Good luck with your project,
Eric
From: stunnel-users [mailto:stunnel-users-bounces@stunnel.org] On Behalf Of
Tamar Pedersen
Sent: Wednesday, January 16, 2019 1:06 PM
To: stunnel-users(a)stunnel.org
Subject: [stunnel-users] How can stunnel use openssl HW cryptodev encryption
Hello,
I am evaluating stunnel, to see if it is a viable solution for providing
encryption in a system that contains an Atmel processor which includes a HW
accelerated encryption block. I am just ramping up on stunnel, and figured
I should capture what I have done so far. My questions will come towards
the end of my email.
My research indicates that stunnel incorporates openssl. I have been able
to use openssl independently, to access the cryptodev HW encryption engine,
in the Linux kernel module located in
/lib/modules/4.14.79/extra/cryptodev.ko. When openssl is run without
accessing the cryptodev engine (cryptodev module not loaded), I get the pure
SW encryption implementation provided by default in openssl. When I run
bench mark speed tests using openssl, using SW encryption, I see the
following results:
# time -v openssl speed -evp aes-128-cbc
Doing aes-128-cbc for 3s on 16 size blocks: 1689887 aes-128-cbc's in 2.95s
Doing aes-128-cbc for 3s on 64 size blocks: 568389 aes-128-cbc's in 2.95s
Doing aes-128-cbc for 3s on 256 size blocks: 151550 aes-128-cbc's in 2.96s
Doing aes-128-cbc for 3s on 1024 size blocks: 38599 aes-128-cbc's in 2.96s
Doing aes-128-cbc for 3s on 8192 size blocks: 4845 aes-128-cbc's in 2.95s
OpenSSL 1.0.2p-fips 14 Aug 2018
built on: reproducible build, date unspecified
options:bn(64,32) rc4(ptr,char) des(idx,cisc,16,long) aes(partial) idea(int)
blowfish(ptr)
compiler: arm-laird-linux-gnueabi-gcc -I. -I.. -I../include -fPIC
-DOPENSSL_PIC -DZLIB_SHARED -DZLIB -DOPENSSL_THREADS -D_REENTRANT
-DDSO_DLFCN -DHAVE_DLFCN_H -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE
-D_FILE_OFFSET_BITS=64 -O3 -DHAVE_CRYPTODEV -DUSE_CRYPTODEV_DIGESTS -Wall
-DOPENSSL_BN_ASM_MONT -DOPENSSL_BN_ASM_GF2m
-I/home/sii/wb50n_space2_legacy_6.0.0.x/wb/buildroot/output/wb50n_space2_leg
acy/host/arm-buildroot-linux-gnueabi/sysroot/usr/local/ssl/fips-2.0/include
-DSHA1_ASM -DSHA256_ASM -DSHA512_ASM -DAES_ASM -DBSAES_ASM -DGHASH_ASM
The 'numbers' are in 1000s of bytes per second processed.
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192
bytes
aes-128-cbc 9165.49k 12331.15k 13107.03k 13353.17k
13454.32k
Command being timed: "openssl speed -evp aes-128-cbc"
User time (seconds): 14.81
System time (seconds): 0.10
Percent of CPU this job got: 99%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0m 15.06s
Average shared text size (kbytes): 0
Average unshared data size (kbytes): 0
Average stack size (kbytes): 0
Average total size (kbytes): 0
Maximum resident set size (kbytes): 13376
Average resident set size (kbytes): 0
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 145
Voluntary context switches: 0
Involuntary context switches: 721
Swaps: 0
File system inputs: 0
File system outputs: 0
Socket messages sent: 0
Socket messages received: 0
Signals delivered: 0
Page size (bytes): 4096
Exit status: 0
#
When I load the cryptodev module, and take advantage of the accelerated
hardware encryption the benchmark tests are significantly faster. Here is
what those results look like.
# modprobe cryptodev
# time -v openssl speed -evp aes-128-cbc
Doing aes-128-cbc for 3s on 16 size blocks: 44163 aes-128-cbc's in 0.12s
Doing aes-128-cbc for 3s on 64 size blocks: 31345 aes-128-cbc's in 0.15s
Doing aes-128-cbc for 3s on 256 size blocks: 18923 aes-128-cbc's in 0.11s
Doing aes-128-cbc for 3s on 1024 size blocks: 13847 aes-128-cbc's in 0.13s
Doing aes-128-cbc for 3s on 8192 size blocks: 8427 aes-128-cbc's in 0.06s
OpenSSL 1.0.2p-fips 14 Aug 2018
built on: reproducible build, date unspecified
options:bn(64,32) rc4(ptr,char) des(idx,cisc,16,long) aes(partial) idea(int)
blowfish(ptr)
compiler: arm-laird-linux-gnueabi-gcc -I. -I.. -I../include -fPIC
-DOPENSSL_PIC -DZLIB_SHARED -DZLIB -DOPENSSL_THREADS -D_REENTRANT
-DDSO_DLFCN -DHAVE_DLFCN_H -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE
-D_FILE_OFFSET_BITS=64 -O3 -DHAVE_CRYPTODEV -DUSE_CRYPTODEV_DIGESTS -Wall
-DOPENSSL_BN_ASM_MONT -DOPENSSL_BN_ASM_GF2m
-I/home/sii/wb50n_space2_legacy_6.0.0.x/wb/buildroot/output/wb50n_space2_leg
acy/host/arm-buildroot-linux-gnueabi/sysroot/usr/local/ssl/fips-2.0/include
-DSHA1_ASM -DSHA256_ASM -DSHA512_ASM -DAES_ASM -DBSAES_ASM -DGHASH_ASM
The 'numbers' are in 1000s of bytes per second processed.
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192
bytes
aes-128-cbc 5888.40k 13373.87k 44038.98k 109071.75k
1150566.40k
Command being timed: "openssl speed -evp aes-128-cbc"
User time (seconds): 0.59
System time (seconds): 8.72
Percent of CPU this job got: 61%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0m 15.11s
Average shared text size (kbytes): 0
Average unshared data size (kbytes): 0
Average stack size (kbytes): 0
Average total size (kbytes): 0
Maximum resident set size (kbytes): 13792
Average resident set size (kbytes): 0
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 144
Voluntary context switches: 41154
Involuntary context switches: 3321
Swaps: 0
File system inputs: 0
File system outputs: 0
Socket messages sent: 0
Socket messages received: 0
Signals delivered: 0
Page size (bytes): 4096
Exit status: 0
#
As can be seen in the results (hi-lighted in red), the average speed to do
aes-128-cbc encryption jumped from around 2.95 s to 0.10 s. Also of
interest is the context switches are significantly higher when running
hardware encryption, because of interrupts and overhead to use the hardware
engine. I can also look at /proc/interrupts and see significant increases
in atmel-aes interrupt counts when using the cryptodev HW acceleration
encryption engine. This gives a good indication that the cryptodev module
is in use, and is doing encryption.
I would like to try to figure out how to allow stunnel to take advantage of
the cryptodev HW acceleration encryption engine available in openssl. I
have made some attempts, but so far, I have not been able to determine if
stunnel is successfully using the cryptodev engine. Here is what I have
done with stunnel. I already have a client and server successfully
communicating with each other using stunnel. To verify this I used the "nc"
utility to send characters back and forth between two different machines.
The stunnel.conf file, on the server, is out of the box. I'm interested in
encrypting on the client side. Here is my current client.conf file, in
/etc/stunnel:
# cat client.conf
debug = 7
output = /tmp/stunnel-server.log
pid = /tmp/stunnel.pid
engine = cryptodev
[test]
verify = 1
client = yes
accept = 127.0.0.1:2000
connect = 192.168.0.220:30000
CAfile = /etc/stunnel/certificate.crt
engineNum = 1
#
I am attempting to set up the cryptodev to be the configured engine for the
client. I am able to start stunnel, using client.conf, as follows:
# stunnel /etc/stunnel/client.conf
#
If I do a "ps" command to display processes, I can see that stunnel is
running in the background. At this point, I can use "nc" to send data, as
follows:
# nc 127.0.0.1 2000 < /tmp/long_file.txt
I am able to see the text from long_file.txt on the server, which is also
running nc. The problem is that I don't see interrupts increasing in
/proc/interrupts, which leaves me wondering if I have not configured stunnel
correctly to use the cryptodev engine. If I try to remove the cryptodev
module as this point, while stunnel is running, I receive a message that it
is in use, as follows:
# modprobe -r cryptodev
modprobe: FATAL: Module cryptodev is in use.
#
If I kill the stunnel process, I am able to successfully remove the
cryptodev module, which seems to suggest stunnel is the process using the
cryptodev module. Also, once I have removed the cryptodev module, I can't
restart stunnel. Instead, I get the following errors back:
# stunnel /etc/stunnel/client.conf
[.] stunnel 5.44 on arm-buildroot-linux-gnueabi platform
[.] Compiled/running with OpenSSL 1.0.2p-fips 14 Aug 2018
[.] Threading:FORK Sockets:POLL,IPv6 TLS:ENGINE,FIPS,OCSP,PSK,SNI
[ ] errno: (*__errno_location ())
[.] Reading configuration from file /etc/stunnel/client.conf
[.] UTF-8 byte order mark not detected
[ ] Enabling support for engine "cryptodev"
[!] error queue: 2606A074: error:2606A074:engine routines:ENGINE_by_id:no
such engine
[!] error queue: 260B6084: error:260B6084:engine routines:DYNAMIC_LOAD:dso
not found
[!] error queue: 25070067: error:25070067:DSO support
routines:DSO_load:could not load the shared library
[!] ENGINE_by_id: 25066067: error:25066067:DSO support
routines:DLFCN_LOAD:could not load the shared library
[!] /etc/stunnel/client.conf:5: "engine = cryptodev": Failed to open the
engine
#
Again, this suggests stunnel is trying to use cryptodev. I just don't know
how to prove I am taking advantage of the HW encryption acceleration engine.
I never see interrupts updating in /proc/interrupts when using nc, while
stunnel is running.
So, here are my questions:
1.) Does it look like I have things set up correctly in client.conf, to
use the cryptodev engine?
2.) If client.conf is correct, how can I prove that stunnel is using the
cryptodev engine, since I don't see the expected interrupts?
One idea is that the cryptodev module might not support the type of
encryption being requested by the certificate, so openssl falls back to the
pure SW encryption implementation. I know the Atmel chip in question
supports the following:
# openssl engine -t -c
(cryptodev) cryptodev engine
[RSA, DSA, DH, DES-CBC, DES-EDE3-CBC, AES-128-CBC, AES-192-CBC, AES-256-CBC,
MD5, SHA1, SHA256, SHA384, SHA512]
[ available ]
(dynamic) Dynamic engine loading support
[ unavailable ]
#
I was able to decode the contents of the certificate, and it says it is
sha256WithRSAEncryption. My engine supports SHA256 and RSA, but does it
support combining, like SHA256WithRSA? I'm not sure. I'll keep chasing
that one.
Thanks for any guidance on how to use the cryptodev in stunnel.
Regards,
Tamar
