Thank you for quick response.
> Are you using blocking or non-blocking I/O?
Non-blocking IO
I've preset bio_send/recv callbacks
I have pair of buffers, transport buffer and application buffer, for
reading and writing (4 buffers total). Application buffers are protected
by mutexes.
Transport buffers are written/read in bio_send/recv (if no async op
pending, otherwise WANT_READ/WRITE).
mbedtls_ssl_xxx work with application buffers.
> Are you using TLS or DTLS? What protocol version, what cipher suite
and what extensions are negotiated?
TLS (over tcp, no lossy channel involved)
version 1.2
> Does your application call mbedtls_ssl_write() and mbedtls_ssl_read()
again with the same buffer if they return MBEDTLS_ERR_SSL_WANT_READ or
MBEDTLS_ERR_SSL_WANT_WRITE?
Well, actually, no. AND it's quite possible, that application outgoing
buffer (std::vector) has been relocated between mbedtls_ssl_write calls,
because app could push data several times while async op was pending and
bio_send returned WANT_WRITE, causing these buffers to resize. So
buf.data() will not be equal to that from previous mbedtls_ssl_write
call. Is this what causes trouble? It's somehow connected to partial
sends? I do call ssl_write inside while-loop, counting sent and unsent
bytes - thought this was enough. But if mbedtls somehow remembers
addresses from previos calls - that might cause problems.
> Do you close the TLS connection if mbedtls_ssl_xxx() returns an error
other than WANT_XXX (or XXX_IN_PROGRESS if you use these features)?
Yes, but that never happens (from handshake to until problem appears)
> What is the value of MBEDTLS_SSL_MAX_CONTENT_LEN (or
MBEDTLS_SSL_OUT_CONTENT_LEN if it's defined)?
Not defined in config, looks like both 16834
>What operating system are you using?
Ubuntu 20, Kali 20
> Is this a client or a server? What TLS stack does the other side run?
Both are written same way, both using same library.
I'll try to prepare test-case code, that reproduces the problem, and
logs, but that will require some time.
10.12.2020 1:07, Gilles Peskine via mbed-tls пишет:
> Hi Андрей,
>
> The behavior you describe is a bug. But there isn't enough information
> to tell whether the bug is in Mbed TLS, in asio-standalone, in some
> other third-party code, or in your application.
>
> Some things to consider:
>
> * Are you using blocking or non-blocking I/O?
> * Are you using TLS or DTLS? What protocol version, what cipher suite
> and what extensions are negotiated?
> * Does your application call mbedtls_ssl_write() and mbedtls_ssl_read()
> again with the same buffer if they return MBEDTLS_ERR_SSL_WANT_READ or
> MBEDTLS_ERR_SSL_WANT_WRITE?
> * Do you close the TLS connection if mbedtls_ssl_xxx() returns an error
> other than WANT_XXX (or XXX_IN_PROGRESS if you use these features)?
> * What is the value of MBEDTLS_SSL_MAX_CONTENT_LEN (or
> MBEDTLS_SSL_OUT_CONTENT_LEN if it's defined)?
> * What operating system are you using?
> * Is this a client or a server? What TLS stack does the other side run?
>
> You'll give others the most chance to help you if you post small,
> complete code to reproduce the problem. I realize this may be difficult.
> A good intermediate way to see what is going on would be to post debug
> logs. To get debug logs, make sure that MBEDTLS_DEBUG_C is enabled and
> call these functions before opening the TLS connection:
>
> mbedtls_ssl_conf_dbg(&ssl_conf, my_debug, stdout);
> mbedtls_debug_set_threshold(2);
>
> See https://tls.mbed.org/kb/how-to/mbedtls-tutorial for a sample version
> of my_debug().
>
> Calls to bio_send() are shown in the logs as
>
> => flush output
> message length: %d, out_left: %d
> ssl->f_send() returned %d
> <= flush output
>
> If they don't show expected numbers, the rest of the logs should give a
> clue as to why.
>
> Hope this helps,
>
By the way, I notice you're using Mbed TLS 2.16.3. This version has
known bugs, including security issues. Please upgrade to the latest Mbed
TLS 2.16.x (currently 2.16.8, very soon 2.16.9) which is a security and
bugfix update, or to the latest release (2.24.0, soon 2.25.0) which has
all the latest bugfixes and features. Looking at the changelog, I don't
see any mention of a bug that could explain your problem, but I might
have missed something.
--
Gilles Peskine
Mbed TLS developer
On 09/12/2020 22:17, Сысоев Андрей via mbed-tls wrote:
> Hello.
>
> I need a little help with mbedtls 2.16.3.
> I'm using it under x86-64 with asio-standalone.
>
> Here's a standard situation:
> - I call mbedtls_ssl_write() to write let's say 8192 bytes of payload
> - it calls my own bio_send() with (8192+21) bytes as len parameter
> - bio_send() returns len=(8192+21), indicating transport data
> correctly written
> - mbedtls_ssl_write() returns 8192, indicating payload send
> GOOD: next I use this value to shift application buffer (erase first
> 8192 bytes), then send next chunk
>
> BUT after some time of running this situation happens:
> - once again, a call to mbedtls_ssl_write() to write let's say 8192
> bytes of payload
> - it calls bio_send() with smaller number, about 5500 bytes as len
> parameter (?? but OK)
> - bio_send() returns len=5500, indicating transport data correctly
> written
> - mbedtls_ssl_write() returns 8192 (??? why not 5500 ???), indicating
> payload send
> BAD: next I use this value to shift application buffer (erase first
> 8192 bytes), this leads to data loss of (8192-5500)=2692 bytes and
> ruins protocol
>
> As you can see, mbedtls_ssl_write() incorrectly reports about sent
> application data (8192 instead of 5500) - is this a bug? How can such
> situation happen under normal operation?
>
> Thanks in advance.
>
Hi Андрей,
The behavior you describe is a bug. But there isn't enough information
to tell whether the bug is in Mbed TLS, in asio-standalone, in some
other third-party code, or in your application.
Some things to consider:
* Are you using blocking or non-blocking I/O?
* Are you using TLS or DTLS? What protocol version, what cipher suite
and what extensions are negotiated?
* Does your application call mbedtls_ssl_write() and mbedtls_ssl_read()
again with the same buffer if they return MBEDTLS_ERR_SSL_WANT_READ or
MBEDTLS_ERR_SSL_WANT_WRITE?
* Do you close the TLS connection if mbedtls_ssl_xxx() returns an error
other than WANT_XXX (or XXX_IN_PROGRESS if you use these features)?
* What is the value of MBEDTLS_SSL_MAX_CONTENT_LEN (or
MBEDTLS_SSL_OUT_CONTENT_LEN if it's defined)?
* What operating system are you using?
* Is this a client or a server? What TLS stack does the other side run?
You'll give others the most chance to help you if you post small,
complete code to reproduce the problem. I realize this may be difficult.
A good intermediate way to see what is going on would be to post debug
logs. To get debug logs, make sure that MBEDTLS_DEBUG_C is enabled and
call these functions before opening the TLS connection:
mbedtls_ssl_conf_dbg(&ssl_conf, my_debug, stdout);
mbedtls_debug_set_threshold(2);
See https://tls.mbed.org/kb/how-to/mbedtls-tutorial for a sample version
of my_debug().
Calls to bio_send() are shown in the logs as
=> flush output
message length: %d, out_left: %d
ssl->f_send() returned %d
<= flush output
If they don't show expected numbers, the rest of the logs should give a
clue as to why.
Hope this helps,
--
Gilles Peskine
Mbed TLS developer
On 09/12/2020 22:17, Сысоев Андрей via mbed-tls wrote:
> Hello.
>
> I need a little help with mbedtls 2.16.3.
> I'm using it under x86-64 with asio-standalone.
>
> Here's a standard situation:
> - I call mbedtls_ssl_write() to write let's say 8192 bytes of payload
> - it calls my own bio_send() with (8192+21) bytes as len parameter
> - bio_send() returns len=(8192+21), indicating transport data
> correctly written
> - mbedtls_ssl_write() returns 8192, indicating payload send
> GOOD: next I use this value to shift application buffer (erase first
> 8192 bytes), then send next chunk
>
> BUT after some time of running this situation happens:
> - once again, a call to mbedtls_ssl_write() to write let's say 8192
> bytes of payload
> - it calls bio_send() with smaller number, about 5500 bytes as len
> parameter (?? but OK)
> - bio_send() returns len=5500, indicating transport data correctly
> written
> - mbedtls_ssl_write() returns 8192 (??? why not 5500 ???), indicating
> payload send
> BAD: next I use this value to shift application buffer (erase first
> 8192 bytes), this leads to data loss of (8192-5500)=2692 bytes and
> ruins protocol
>
> As you can see, mbedtls_ssl_write() incorrectly reports about sent
> application data (8192 instead of 5500) - is this a bug? How can such
> situation happen under normal operation?
>
> Thanks in advance.
>
Hello.
I need a little help with mbedtls 2.16.3.
I'm using it under x86-64 with asio-standalone.
Here's a standard situation:
- I call mbedtls_ssl_write() to write let's say 8192 bytes of payload
- it calls my own bio_send() with (8192+21) bytes as len parameter
- bio_send() returns len=(8192+21), indicating transport data correctly
written
- mbedtls_ssl_write() returns 8192, indicating payload send
GOOD: next I use this value to shift application buffer (erase first
8192 bytes), then send next chunk
BUT after some time of running this situation happens:
- once again, a call to mbedtls_ssl_write() to write let's say 8192
bytes of payload
- it calls bio_send() with smaller number, about 5500 bytes as len
parameter (?? but OK)
- bio_send() returns len=5500, indicating transport data correctly written
- mbedtls_ssl_write() returns 8192 (??? why not 5500 ???), indicating
payload send
BAD: next I use this value to shift application buffer (erase first 8192
bytes), this leads to data loss of (8192-5500)=2692 bytes and ruins protocol
As you can see, mbedtls_ssl_write() incorrectly reports about sent
application data (8192 instead of 5500) - is this a bug? How can such
situation happen under normal operation?
Thanks in advance.
Hi Farhad,
Mbed TLS currently supports hardware acceleration through alternative
implementations of the corresponding modules or functions. See
https://tls.mbed.org/kb/development/hw_acc_guidelines . This mechanism
is available for symmetric cryptography and partially for RSA and ECC.
There is some work in progress on a new mechanism for hardware
acceleration through the psa_xxx() API, which will be available for all
algorithms. You can follow the work in progress on the “Unified driver
interface: API design and prototype” epic at
https://github.com/ARMmbed/mbedtls/projects/2#column-8543266 .
Hope this helps,
--
Gilles Peskine
Mbed TLS developer
On 04/12/2020 11:20, saghili via mbed-tls wrote:
> Dear Sir/Madam,
>
> Our platform is a quad core Cortex A53 running PetaLinux.
> In our hardware, "AF_ALG" module has performance accelerations
> available through the Linux crypto drivers.
> Is it possible that we have "AF_ALG" for offloading crypto operations?
>
> Best regards,
> Farhad
Dear Sir/Madam,
Our platform is a quad core Cortex A53 running PetaLinux.
In our hardware, "AF_ALG" module has performance accelerations available
through the Linux crypto drivers.
Is it possible that we have "AF_ALG" for offloading crypto operations?
Best regards,
Farhad
Hello, I am using ESP32 Dev Module, which supports MbedTLS. I have two
questions, but I can't find the answer on the forum:
1.Is there any way to import RSA keys from string(ideally from PEM format)
to mbedtls_pk context?
2.How to encrypt with RSA private key and decrypt with RSA public key?
Thanks
Radim Kohout
Thanks Gilles. I have use mbedtls_ecdsa_sign and got the raw buffer output
of R & S values.
On Sun, Nov 22, 2020, 9:26 PM Gilles Peskine via mbed-tls <
mbed-tls(a)lists.trustedfirmware.org> wrote:
> Hi Roshini,
>
> Mathematically, an ES256 (ECDSA over the curve P256R1) signature is a
> pair of numbers (r,s) between 1 and an upper bound which is very
> slightly less than 2^256. There are two common representations for this
> signature. JWA uses the “raw” representation: two big-endian numbers
> represented each with exactly 32 bytes, concatenated together.
> mbedtls_ecdsa_write_signature uses the ASN.1 DER representation, which
> as you noticed represents each number in a type+length+value format.
>
> The DER format removes leading zeros from the number, then adds a
> leading 0 bit to each number which is a sign bit (the numbers in an
> ECDSA signature are always positive, but DER can also represent negative
> numbers). Therefore each number has a roughly 1/2 chance of using 33
> value bytes with a leading 0 byte (1 sign bit + 7 value bits, all 0), a
> 63/128 chance of using 32 value bytes, and a 1/128 chance of using 31
> value bytes or less because the 7 most significant bits of the number
> were 0. A shorter number in an ECDSA signature is not invalid, it's a
> 1/128 chance (independently for each of r and s).
>
> To get the signature in raw format with Mbed TLS, the easiest way is to
> use the PSA API, where the output of psa_sign_hash() for ECDSA is the
> raw format. With the classic Mbed TLS API, the easiest way is to call
> mbedtls_ecdsa_sign() or mbedtls_ecdsa_sign_det_ext() to get r and s as
> bignums, then use mbedtls_mpi_write_binary() to write r and s with their
> exact size into the output buffer. You can find an example in the
> internal function psa_ecdsa_sign():
>
> https://github.com/ARMmbed/mbedtls/blob/mbedtls-2.24.0/library/psa_crypto.c…
>
> Hope this helps,
>
> --
> Gilles Peskine
> Mbed TLS developer
>
> On 22/11/2020 10:12, ROSHINI DEVI via mbed-tls wrote:
> > Hello all,
> >
> > I need to sign the message using ES256 algorithm. After doing
> > necessary initializations, I called API
> > - mbedtls_ecdsa_write_signature() API and it gave me signature in ASN1
> > encoded form and there was no error generated by this API.
> > After getting the signature, I need the r & s values to create JWT
> > Token. So, I wrote my custom function to parse the signature buffer
> > and get the R & S values of it.
> > It was working fine. Sometimes, I am getting an invalid signature as
> > shown below signature DER buffer -
> >
> > 30 43 02 1f 31 92 8d 22 10 41 86 25 68 7f 42 81 26 0f 37 bc 7f 38 b7
> > d5 1a 6b 69 31 07 34 11 a6 04 e5 90 02 20 23 26 f8 b9 80 cf 2c 25 c8
> > 04 b4 ac 43 51 6a 04 a6 af 8f 94 36 f8 cf 35 c2 94 cc df de db 92 b2
> >
> > The reason for invalid is -
> > 1st byte represents ASN1 sequence, followed by length and 3rd byter
> > indicates it is an integer.
> > Ideally, 4th byte indicates length of r-value, it should have been 32
> > or 33 bytes ( in case of padding with 00 ). You can see in the above
> > buffer it is 0x1F ( 31 bytes ). It is really weird how it is possible
> > to get the signature length of 31 bytes.
> >
> > It is blocking me for generation of JWT token, where in RFC 7518
> > - https://tools.ietf.org/html/rfc7518#page-9 , it says R & S must be
> > 32 bytes long. And, the generation is failing.
> >
> > It is of high priority for me. If anyone can provide your suggestions
> > on this issue, it would be really great. Thanks in advance
> >
> > Thanks,
> > Roshini
> >
>
>
> --
> mbed-tls mailing list
> mbed-tls(a)lists.trustedfirmware.org
> https://lists.trustedfirmware.org/mailman/listinfo/mbed-tls
>
Hi Roshini,
Mathematically, an ES256 (ECDSA over the curve P256R1) signature is a
pair of numbers (r,s) between 1 and an upper bound which is very
slightly less than 2^256. There are two common representations for this
signature. JWA uses the “raw” representation: two big-endian numbers
represented each with exactly 32 bytes, concatenated together.
mbedtls_ecdsa_write_signature uses the ASN.1 DER representation, which
as you noticed represents each number in a type+length+value format.
The DER format removes leading zeros from the number, then adds a
leading 0 bit to each number which is a sign bit (the numbers in an
ECDSA signature are always positive, but DER can also represent negative
numbers). Therefore each number has a roughly 1/2 chance of using 33
value bytes with a leading 0 byte (1 sign bit + 7 value bits, all 0), a
63/128 chance of using 32 value bytes, and a 1/128 chance of using 31
value bytes or less because the 7 most significant bits of the number
were 0. A shorter number in an ECDSA signature is not invalid, it's a
1/128 chance (independently for each of r and s).
To get the signature in raw format with Mbed TLS, the easiest way is to
use the PSA API, where the output of psa_sign_hash() for ECDSA is the
raw format. With the classic Mbed TLS API, the easiest way is to call
mbedtls_ecdsa_sign() or mbedtls_ecdsa_sign_det_ext() to get r and s as
bignums, then use mbedtls_mpi_write_binary() to write r and s with their
exact size into the output buffer. You can find an example in the
internal function psa_ecdsa_sign():
https://github.com/ARMmbed/mbedtls/blob/mbedtls-2.24.0/library/psa_crypto.c…
Hope this helps,
--
Gilles Peskine
Mbed TLS developer
On 22/11/2020 10:12, ROSHINI DEVI via mbed-tls wrote:
> Hello all,
>
> I need to sign the message using ES256 algorithm. After doing
> necessary initializations, I called API
> - mbedtls_ecdsa_write_signature() API and it gave me signature in ASN1
> encoded form and there was no error generated by this API.
> After getting the signature, I need the r & s values to create JWT
> Token. So, I wrote my custom function to parse the signature buffer
> and get the R & S values of it.
> It was working fine. Sometimes, I am getting an invalid signature as
> shown below signature DER buffer -
>
> 30 43 02 1f 31 92 8d 22 10 41 86 25 68 7f 42 81 26 0f 37 bc 7f 38 b7
> d5 1a 6b 69 31 07 34 11 a6 04 e5 90 02 20 23 26 f8 b9 80 cf 2c 25 c8
> 04 b4 ac 43 51 6a 04 a6 af 8f 94 36 f8 cf 35 c2 94 cc df de db 92 b2
>
> The reason for invalid is -
> 1st byte represents ASN1 sequence, followed by length and 3rd byter
> indicates it is an integer.
> Ideally, 4th byte indicates length of r-value, it should have been 32
> or 33 bytes ( in case of padding with 00 ). You can see in the above
> buffer it is 0x1F ( 31 bytes ). It is really weird how it is possible
> to get the signature length of 31 bytes.
>
> It is blocking me for generation of JWT token, where in RFC 7518
> - https://tools.ietf.org/html/rfc7518#page-9 , it says R & S must be
> 32 bytes long. And, the generation is failing.
>
> It is of high priority for me. If anyone can provide your suggestions
> on this issue, it would be really great. Thanks in advance
>
> Thanks,
> Roshini
>
Hello all,
I need to sign the message using ES256 algorithm. After doing
necessary initializations, I called API - mbedtls_ecdsa_write_signature()
API and it gave me signature in ASN1 encoded form and there was no error
generated by this API.
After getting the signature, I need the r & s values to create JWT Token.
So, I wrote my custom function to parse the signature buffer and get the R
& S values of it.
It was working fine. Sometimes, I am getting an invalid signature as shown
below signature DER buffer -
30 43 02 1f 31 92 8d 22 10 41 86 25 68 7f 42 81 26 0f 37 bc 7f 38 b7 d5 1a
6b 69 31 07 34 11 a6 04 e5 90 02 20 23 26 f8 b9 80 cf 2c 25 c8 04 b4 ac 43
51 6a 04 a6 af 8f 94 36 f8 cf 35 c2 94 cc df de db 92 b2
The reason for invalid is -
1st byte represents ASN1 sequence, followed by length and 3rd byter
indicates it is an integer.
Ideally, 4th byte indicates length of r-value, it should have been 32 or 33
bytes ( in case of padding with 00 ). You can see in the above buffer it is
0x1F ( 31 bytes ). It is really weird how it is possible to get the
signature length of 31 bytes.
It is blocking me for generation of JWT token, where in RFC 7518 -
https://tools.ietf.org/html/rfc7518#page-9 , it says R & S must be 32 bytes
long. And, the generation is failing.
It is of high priority for me. If anyone can provide your suggestions on
this issue, it would be really great. Thanks in advance
Thanks,
Roshini
Hi everyone,
I am a Mtech student from Indian Institute of Science, Bangalore(India).
Currently, I am crediting computer security course. As the course project,
the professor has asked us to rewrite Mbedtls using Rust language. The
entire class will work on the single project with each person working on a
single module.
I am having trouble finding information regarding Mbedtls architecture, its
modules and their working. I don't even know all the right resources I need
to work on the project.
It would save a lot of time if someone could point me to the right
resources regarding Mbedtls needed for this project.
Sincerely,
Eikansh Gupta
I forgot to mention that there is a work in progress to add PKCS#7 parsing:
https://github.com/ARMmbed/mbedtls/pull/3431
This is an external contribution so its addition to Mbed TLS depends not
only on us maintainers' review bandwidth, but also on the availability
of the kind contributor.
I'm not familiar with .p7* formats so I don't know whether the support
added by this pull request is sufficient to cover all of those.
--
Gilles Peskine
Mbed TLS developer
On 06/11/2020 13:50, Alvaro Gonzalez via mbed-tls wrote:
>
> Hello mbed-tls mailing list.
>
> �
>
> Does mbed-tls comply PKCS7? Can handle .p7, .p7b and/or .p7a extension
> files?
>
> �
>
> Best Regards.
>
> �
>
>
Hi Nick,
It would be great to have even partial support of PKCS#7 in Mbed TLS and
we would welcome your contribution!
You can find some guidance in CONTRIBUTING.md
(https://github.com/ARMmbed/mbedtls/blob/development/CONTRIBUTING.md).
Feel free to ask on the mailing list if anything is unclear.
Note that there is a work in progress for adding PKCS#7 parsing:
https://github.com/ARMmbed/mbedtls/pull/3431 . It may help to see what
it does, but also note the review comments that point out some remaining
issues. If you and naynajain work on parsing and generation at the same
time, you'll need to synchronize since both sides will need to create
pkcs7.[hc].
--
Gilles Peskine
Mbed TLS developer
On 10/11/2020 17:28, Nick Child via mbed-tls wrote:
> Hello,
>
> For one of my projects, I had to create a PKCS7 generation/builder. I
> noticed mbedtls currently has no support for PKCS7. After much trial
> and error, I was able to use mbedtls functions to create a PKCS7
> structure for Signed Data. I was wondering if this something that
> might be useful in later versions of mbedtls? The code currently has a
> long way to go until it meets mbedtls coding standards, but I figured
> I would ask if it is even possible and worth the efforts before
> getting into it. I am also a rookie when it comes to open source
> contributions, so I was hoping for some guidance regarding merging
> upstream.
>
> Thanks for your time,
>
> Nick Child
>
Hello,
For one of my projects, I had to create a PKCS7 generation/builder. I
noticed mbedtls currently has no support for PKCS7. After much trial and
error, I was able to use mbedtls functions to create a PKCS7 structure for
Signed Data. I was wondering if this something that might be useful in
later versions of mbedtls? The code currently has a long way to go until it
meets mbedtls coding standards, but I figured I would ask if it is even
possible and worth the efforts before getting into it. I am also a rookie
when it comes to open source contributions, so I was hoping for some
guidance regarding merging upstream.
Thanks for your time,
Nick Child
Hello,
Mbed TLS does not currently support SRP and it is not on our roadmap
(https://developer.trustedfirmware.org/w/mbed-tls/roadmap/). Arm does
not intend to work on it, but support can be added if someone else
contributes it.
If you are interested in contributing SRP support, please discuss it on
this list first to settle some potential issues: conflicts with other
work (in particular TLS 1.3 preparation, which involves some refactoring
of existing TLS code), review bandwidth schedule, test plan.
--
Gilles Peskine
Mbed TLS developer
On 09/11/2020 14:01, Gijs Peskens via mbed-tls wrote:
>
> For an Open Source project we started using Mbed-TLS to do AES
> encryption and, in a future version, will use Mbed-TLS for DTLS.
> Part of the protocol we support requires TLS-SRP (either via DTLS or
> via EAP), I’m unable to find anything relating to TLS-SRP support.
>
> Does Mbed-TLS support TLS-SRP currently? And if not is there intention
> to add it in a future release?
>
> Br,
>
> Gijs Peskens
>
>
Hi Gijs,
I am not sure what TLS-SRP support is, could you please point me to the standard defining it?
Best regards,
Janos
From: mbed-tls <mbed-tls-bounces(a)lists.trustedfirmware.org> on behalf of Gijs Peskens via mbed-tls <mbed-tls(a)lists.trustedfirmware.org>
Reply to: Gijs Peskens <gijsje(a)heteigenwijsje.nl>
Date: Monday, 9 November 2020 at 13:02
To: "mbed-tls(a)lists.trustedfirmware.org" <mbed-tls(a)lists.trustedfirmware.org>
Subject: [mbed-tls] TLS-SRP Support
For an Open Source project we started using Mbed-TLS to do AES encryption and, in a future version, will use Mbed-TLS for DTLS.
Part of the protocol we support requires TLS-SRP (either via DTLS or via EAP), I’m unable to find anything relating to TLS-SRP support.
Does Mbed-TLS support TLS-SRP currently? And if not is there intention to add it in a future release?
Br,
Gijs Peskens
For an Open Source project we started using Mbed-TLS to do AES
encryption and, in a future version, will use Mbed-TLS for DTLS.
Part of the protocol we support requires TLS-SRP (either via DTLS or via
EAP), I’m unable to find anything relating to TLS-SRP support.
Does Mbed-TLS support TLS-SRP currently? And if not is there intention
to add it in a future release?
Br,
Gijs Peskens
Hi Newt,
This is normal and happens not just to Chinese characters, but to all non-ASCII characters. This supposed to be a feature of Mbed TLS, to ensure that we return something printable whether the platform can handle the original encoding or not. Of course we can consider providing a way to add an option to disable this feature: if you would like to submit a PR, please let us discuss first what can be done. If you wouldn't like to submit a PR, then please raise an issue on github for this feature request.
Until this feature is implemented, you can access the original encoding in the `val` field of the `mbedtls_x509_name` parameter you would be passing to `mbedtls_x509_dn_gets()`.
Regards,
Janos
On 06/11/2020, 03:54, "mbed-tls on behalf of 马瑞宜 via mbed-tls" <mbed-tls-bounces(a)lists.trustedfirmware.org on behalf of mbed-tls(a)lists.trustedfirmware.org> wrote:
Hello everyone,
I have this certificate blob and I'm using mbedtls to read this, but after called mbedtls_x509_crt_info() or mbedtls_x509_dn_gets(), the chinese characters got garbled. I have googled this, read the mbedtls knowledge base and searched the issues and got no luck. The field i want to parse is the subject field and the issuer field. and currently I cannot provide the certificate blob due to security reasons.
Any help would be much appreciated.
Sincerely,
Newt Ma
--
mbed-tls mailing list
mbed-tls(a)lists.trustedfirmware.org
https://lists.trustedfirmware.org/mailman/listinfo/mbed-tls
Hello everyone,
I have this certificate blob and I'm using mbedtls to read this, but after called mbedtls_x509_crt_info() or mbedtls_x509_dn_gets(), the chinese characters got garbled. I have googled this, read the mbedtls knowledge base and searched the issues and got no luck. The field i want to parse is the subject field and the issuer field. and currently I cannot provide the certificate blob due to security reasons.
Any help would be much appreciated.
Sincerely,
Newt Ma
Hi Sawyer,
After looking at the issues in more detail I would like to be more precise about CVE-2018-1000520:
* It is not a security issue in the context of TLS 1.2
* It can be a security issue if TLS 1.0 or TLS 1.1 is used
* The severity is so low that we decided not fixing it ourselves, but to open it up for community contributions
* The corresponding issue has been closed down by mistake, I am reopening it now: https://github.com/ARMmbed/mbedtls/issues/1561
(Many thanks to Simon Butcher for noticing this and pointing it out.)
Please let me know if I you would like to know more about this issue.
Best regards,
Janos
(Mbed TLS developer)
From: mbed-tls <mbed-tls-bounces(a)lists.trustedfirmware.org> on behalf of Janos Follath via mbed-tls <mbed-tls(a)lists.trustedfirmware.org>
Reply to: Janos Follath <Janos.Follath(a)arm.com>
Date: Wednesday, 28 October 2020 at 09:42
To: Sawyer Liu <sawyer.liu(a)nxp.com>
Cc: "mbed-tls(a)lists.trustedfirmware.org" <mbed-tls(a)lists.trustedfirmware.org>
Subject: Re: [mbed-tls] About mbedtls CVE
Hi Sawyer,
Thank you for your interest in Mbed TLS. Currently the status of these CVE’s is:
- CVE-2020-16150 has been fixed in the latest Mbed TLS release
- CVE-2018-1000520 is not a security issue, it had been studied and rejected
- CVE-2016-3739 is a vulnerability in an application using Mbed TLS but not in Mbed TLS itself, also it too had been fixed.
Does this answer your question?
(Also, I would like to make a minor clarification: we are not Arm Support. As far as I know Arm does not offer official support for Mbed TLS. Arm only contributes engineers to the Mbed TLS project, and at the moment these engineers are the maintainers of Mbed TLS. We are on this mailing list and try to answer questions, but we are not doing that as official support provided by Arm, but as members of the community. Mbed TLS is supported by the community and this mailing list is indeed the right place to get that support. I apologise for the nitpick, I just wanted to make sure that we are not giving the wrong impressions.)
Best regards,
Janos
(Mbed TLS developer)
From: mbed-tls <mbed-tls-bounces(a)lists.trustedfirmware.org> on behalf of Sawyer Liu via mbed-tls <mbed-tls(a)lists.trustedfirmware.org>
Reply to: Sawyer Liu <sawyer.liu(a)nxp.com>
Date: Wednesday, 28 October 2020 at 01:59
To: "mbed-tls(a)lists.trustedfirmware.org" <mbed-tls(a)lists.trustedfirmware.org>
Subject: [mbed-tls] About mbedtls CVE
Hello ARM Support,
About below CVEs, any update? Thanks.
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-16150<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcve.mitre…>
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-1000520https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3739
Best Regards
Sawyer Liu
Microcontrollers, NXP Semiconductors
Hello,
On 05/11/2020 17:49, François Beerten via mbed-tls wrote:
> Hi,
>
> Thank you Gilles for the detailed reply.
>
> Do you prefer that discussion about PSA Crypto API spec go on mailing
> list instead of here ? Is there some room for evolution or is the spec
> already in a frozen released state ?
Please use the psa-crypto list since there may be participants there who
don't care about Mbed TLS.
Version 1.0 of the PSA Crypto API is official so we won't make
incompatible changes unless there is a compelling reason. We can, and
will, add features in 1.x versions of the specification. Among planned
features are: more algorithm declarations, key wrapping, key stretching,
and a better treatment of key establishment (including password-based
key establishment).
>
> For new algorithms, it's of course preferable that they're defined in
> the spec itself. But does the mbedtls project want to supports all
> algorithms that will be used with PSA Crypto API ?
Mbed TLS intends to be a reference implementation of the PSA crypto API.
However it isn't clear whether this means that Mbed TLS will eventually
support all algorithms that the API declares: we intend to support all
methods, but not necessarily all algorithms. A conforming implementation
of the API is allowed to support any subset of the algorithms.
We (here meaning Arm, not Mbed TLS) don't have a formal policy to decide
whether to include a declaration for an algorithm, but here are some
criteria that we're likely to follow:
* There should be a public specification. (This can be a document that's
only for purchase, such as an ISO standard.)
* The algorithm should either be in good standing, or in current use in
legacy protocols.
* The bar is low for adding an algorithm that just requires a #define.
It's a lot higher if a new function is needed.
* Availability in Mbed TLS is not required.
>
> For pure ED25519 and ED448 with scattered data, there's one big
> gotcha. You need to generate twice a hash that includes the message.
> Thus the implementation needs to be able to access the buffers of the
> message twice. With a piece of the message given only once as in the
> init-update-finish scheme, that does not work well.
>
> From reading the document on the PSA Crypto driver API, a transparent
> driver benefits from the management of keys done by the mbedtls
> implementation. But what benefit is there for a driver working with
> opaque keys which has to fully handle the protections and restrictions
> of keys internally ?
>
One of the driving goals of PSA is to make security unobtrusive, and to
facilitate security improvements. A unified interface to key management
makes it easy to upgrade from having all keys inside, to using a
single-chip application separation technology (MMU, MPU, secure enclave,
…), to wrapping keys in a secure element and storing the wrapped key
externally, to storing keys in a secure element (which protects against
undeletion). When an application uses a key, it doesn't need to care
where the key is stored.
Best regards,
--
Gilles Peskine
> Best,
>
> François.
>
>
> On 11/2/20 11:01 PM, Gilles Peskine via mbed-tls wrote:
>> Hello,
>>
>> Thank you for your interest in the PSA crypto API.
>>
>> On 28/10/2020 15:20, François Beerten via mbed-tls wrote:
>>> Hi everybody,
>>>
>>> After reading the PSA Crypto API specs (as on
>>> https://armmbed.github.io/mbed-crypto/html/overview/functionality.html)
>>> and looking at the mbed TLS library, a few questions came up.
>>>
>>> Is there some repository with the sources of the PSA Crypto API specs
>>> where one can follow the evolution and eventually send proposals and
>>> patches ?
>>>
>> The PSA specification drafts are not public. You can send feedback about
>> the PSA Crypto application and driver interfaces on the psa-crypto
>> mailing list (psa-crypto(a)lists.trustedfirmware.org,
>> https://lists.trustedfirmware.org/mailman/listinfo/psa-crypto). If you
>> prefer to send confidential feedback, you can email mbed-crypto(a)arm.com
>> (feedback at this address will only be discussed inside Arm). An issue
>> in the Mbed TLS repository will also reach PSA Crypto architects.
>>
>>> A note says "Hash suspend and resume is not defined for the SHA3
>>> family of hash algorithms". Why are they not defined for SHA3 ?
>>>
>> The hash suspend/resume operations marshall the internal state of the
>> hash operation. They mimic an existing JavaCard API
>> (https://docs.oracle.com/javacard/3.0.5/api/javacard/security/InitializedMes…).
>>
>> There is a de facto standard representation of the internal state for
>> common Merkle-Damgård constructions, which covers all the currently
>> defined hash algorithms except SHA3. If there's interest in this
>> functionality, we could standardize a representation for SHA3.
>>
>>> How can or should one add support in PSA Crypto AP for not yet defined
>>> algorithms (for example a KDF) ?
>>>
>> Answer from a PSA Crypto architect: preferably by requesting an encoding
>> for this KDF as a PSA_ALG_xxx value (as well as new
>> PSA_KEY_DERIVATION_INPUT_xxx values if applicable). If you can't do
>> that, use an encoding in the vendor range (most significant bit set).
>>
>> The world of key derivation functions is unfortunately messy: there are
>> many similar, but not functionally equivalent constructions (such as
>> hashing a secret together with a nonce, formatted in all kinds of
>> different ways). The set of KDF in PSA Crypto 1.0.0 was the minimum set
>> required for the TLS protocol. We expect 1.0.x updates to define more
>> KDF algorithms.
>>
>> Answer from an Mbed TLS maintainer: contributing an implementation would
>> be appreciated (but not required).
>>
>>> In multipart operations, can the user reuse the input buffers
>>> immediately after doing an 'update' (for example after
>>> psa_hash_update()) ? And can he reuse the input buffers immediately
>>> after some "setup" functions like psa_cipher_set_iv() or
>>> psa_aead_set_nonce() ?
>>>
>> Yes. PSA crypto API functions that take a buffer as a parameter never
>> take ownership of that buffer. Once the function returns, you can do
>> whatever you want with the buffer.
>>
>> The PSA specification even guarantees that you can use the same buffer,
>> or overlapping buffers, as inputs and outputs to the same function call.
>> However beware that the Mbed TLS implementation does not always support
>> such overlap (https://github.com/ARMmbed/mbedtls/issues/3266).
>>
>>> Do you plan to support (pure) ED25519 and ED448 only via
>>> psa_sign_message() and psa_verify_message() ? What about messages in
>>> multiple chunks ?
>>>
>> We plan to add a multi-part message signature interface, both for the
>> sake of pureEdDSA and suitable for Mbed TLS's restartable ECDSA. I
>> expect the design to be “what you'd expect” but I haven't yet verified
>> that there aren't any gotchas.
>>
>>> In psa_asymmetric_encrypt(), why is the salt provided explicitely.
>>> Shouldn't it be generated randomly internally when needed ?
>>>
>> Some applications use a fixed or deterministic salt which they check on
>> decryption. Note that this parameter is what PKCS#1 calls “label”.
>>
>>> With PSA Crypto API, you define a flexible API for cryptographic
>>> operations. Apparently, other providers could make their own
>>> implementation of PSA Crypto API. Will mbed TLS then be able to use
>>> those alternate PSA Crypto API implementations ? How would that work
>>> practically ?
>>>
>> The X.509 and TLS layer of Mbed TLS are currently designed to use the
>> mbedtls_xxx crypto API. We have already added partial support for the
>> psa_xxx crypto API (with MBEDTLS_USE_PSA_CRYPTO), however it is not yet
>> possible to fully decouple the X.509/TLS layers from the Mbed TLS crypto
>> implementation. (I think this is already possible for a small set of
>> cipher suites, but it isn't something that we've tried or currently
>> actively support.) Before this can happen, some Mbed TLS APIs need to
>> change, which will happen in 2021 with Mbed TLS 3.0. After that, we plan
>> to decouple the PSA crypto reference implementation (Mbed TLS's current
>> crypto implementation) from the X.509/TLS layer (which will remain “Mbed
>> TLS”). Our plans
>> (https://developer.trustedfirmware.org/w/mbed-tls/roadmap/) that far
>> into the future are still vague and may change.
>>
>> Note that for the most common case of wanting a different implementation
>> of cryptography, which is to leverage hardware such as accelerators and
>> secure elements, PSA is defining a driver interface which is currently
>> being implemented in Mbed TLS
>> (https://github.com/ARMmbed/mbedtls/blob/development/docs/proposed/psa-drive…).
>>
>> The driver interface lets you combine mechanisms supported by your
>> hardware with Mbed TLS's implementation for mechanisms without hardware
>> support.
>>
Hi Francois,
The workshop slides and recordings are now available here - https://www.trustedfirmware.org/meetings/mbed-tls-workshop/
Regards,
Shebu
From: mbed-tls <mbed-tls-bounces(a)lists.trustedfirmware.org> On Behalf Of François Beerten via mbed-tls
Sent: Thursday, November 5, 2020 4:52 PM
To: mbed-tls(a)lists.trustedfirmware.org
Subject: Re: [mbed-tls] Mbed TLS Virtual Workshop Tomorrow
Hi Shebu,
Will you post the slides of the presentations of the workshop ?
Thanks,
François.
On 11/2/20 9:01 PM, Shebu Varghese Kuriakose via mbed-tls wrote:
Hi All,
Gentle reminder about the Mbed TLS workshop tomorrow (Tuesday, November 3rd) from 2 to 6pm GMT.
See agenda and zoom link here - https://www.trustedfirmware.org/meetings/mbed-tls-workshop/
Thanks,
Shebu
-----Original Appointment-----
From: Trusted Firmware Public Meetings <linaro.org_havjv2figrh5egaiurb229pd8c(a)group.calendar.google.com><mailto:linaro.org_havjv2figrh5egaiurb229pd8c@group.calendar.google.com>
Sent: Friday, October 23, 2020 12:32 AM
To: Trusted Firmware Public Meetings; Shebu Varghese Kuriakose; mbed-tls(a)lists.trustedfirmware.org<mailto:mbed-tls@lists.trustedfirmware.org>; Don Harbin; psa-crypto(a)lists.trustedfirmware.org<mailto:psa-crypto@lists.trustedfirmware.org>; Dave Rodgman
Subject: Mbed TLS Virtual Workshop
When: Tuesday, November 3, 2020 2:00 PM-6:00 PM (UTC+00:00) Dublin, Edinburgh, Lisbon, London.
Where: Zoom: https://linaro-org.zoom.us/j/95315200315?pwd=ZDJGc1BZMHZLV29DTmpGUllmMjB1UT…
You have been invited to the following event.
Mbed TLS Virtual Workshop
When
Tue Nov 3, 2020 7am – 11am Mountain Standard Time - Phoenix
Where
Zoom: https://linaro-org.zoom.us/j/95315200315?pwd=ZDJGc1BZMHZLV29DTmpGUllmMjB1UT… (map<https://www.google.com/maps/search/Zoom:+https:%2F%2Flinaro-org.zoom.us%2Fj…>)
Calendar
shebu.varghesekuriakose(a)arm.com<mailto:shebu.varghesekuriakose@arm.com>
Who
•
Don Harbin - creator
•
shebu.varghesekuriakose(a)arm.com<mailto:shebu.varghesekuriakose@arm.com>
•
mbed-tls(a)lists.trustedfirmware.org<mailto:mbed-tls@lists.trustedfirmware.org>
•
psa-crypto(a)lists.trustedfirmware.org<mailto:psa-crypto@lists.trustedfirmware.org>
•
dave.rodgman(a)arm.com<mailto:dave.rodgman@arm.com>
more details »<https://www.google.com/calendar/event?action=VIEW&eid=NHVvY2FxY2o4Njk3MWZkd…>
Hi,
Trustedfirmware.org community project would like to invite you to the Mbed TLS Virtual Workshop.
The purpose of the workshop is to bring together the Mbed TLS community including maintainers, contributors and users to discuss
* The future direction of the project and
* Ways to improve community collaboration
Here is the agenda for the workshop.
Topic Time (in GMT)
Welcome 2.00 - 2.10pm
Constant-time code 2.10 – 2.30pm
Processes - how does work get scheduled? 2.30 – 2.50pm
PSA Crypto APIs 2.50 – 3.20pm
PSA Crypto for Silicon Labs Wireless
MCUs - Why, What, Where and When 3.20 – 3.50pm
Break
Roadmap, TLS1.3 Update 4.10 – 4.30pm
Mbed TLS 3.0 Plans, Scope 4.30 – 5.00pm
How do I contribute my first review
and be an effective Mbed TLS reviewer 5.00 – 5.30pm
Regards,
Don Harbin
Trusted Firmware Community Manager
==============Zoom details below:====================
Trusted Firmware is inviting you to a scheduled Zoom meeting.
Topic: Mbed TLS Virtual Workshop
Time: Nov 3, 2020 02:00 PM Greenwich Mean Time
Join Zoom Meeting
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Meeting ID: 953 1520 0315
Passcode: 143755
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Hi Shebu,
Will you post the slides of the presentations of the workshop ?
Thanks,
François.
On 11/2/20 9:01 PM, Shebu Varghese Kuriakose via mbed-tls wrote:
>
> Hi All,
>
> Gentle reminder about the Mbed TLS workshop tomorrow (Tuesday,
> November 3^rd ) from 2 to 6pm GMT.
>
> See agenda and zoom link here -
> https://www.trustedfirmware.org/meetings/mbed-tls-workshop/
> <https://www.trustedfirmware.org/meetings/mbed-tls-workshop/>
>
> Thanks,
>
> Shebu
>
> -----Original Appointment-----
> *From:* Trusted Firmware Public Meetings
> <linaro.org_havjv2figrh5egaiurb229pd8c(a)group.calendar.google.com>
> *Sent:* Friday, October 23, 2020 12:32 AM
> *To:* Trusted Firmware Public Meetings; Shebu Varghese Kuriakose;
> mbed-tls(a)lists.trustedfirmware.org; Don Harbin;
> psa-crypto(a)lists.trustedfirmware.org; Dave Rodgman
> *Subject:* Mbed TLS Virtual Workshop
> *When:* Tuesday, November 3, 2020 2:00 PM-6:00 PM (UTC+00:00) Dublin,
> Edinburgh, Lisbon, London.
> *Where:* Zoom:
> https://linaro-org.zoom.us/j/95315200315?pwd=ZDJGc1BZMHZLV29DTmpGUllmMjB1UT…
>
>
> *You have been invited to the following event.*
>
>
> Mbed TLS Virtual Workshop
>
> When
>
>
>
> Tue Nov 3, 2020 7am – 11am Mountain Standard Time - Phoenix
>
> Where
>
>
>
> Zoom:
> https://linaro-org.zoom.us/j/95315200315?pwd=ZDJGc1BZMHZLV29DTmpGUllmMjB1UT…
> (map
> <https://www.google.com/maps/search/Zoom:+https:%2F%2Flinaro-org.zoom.us%2Fj…>)
>
> Calendar
>
>
>
> shebu.varghesekuriakose(a)arm.com <mailto:shebu.varghesekuriakose@arm.com>
>
> Who
>
>
>
> •
>
>
>
> Don Harbin- creator
>
> •
>
>
>
> shebu.varghesekuriakose(a)arm.com <mailto:shebu.varghesekuriakose@arm.com>
>
> •
>
>
>
> mbed-tls(a)lists.trustedfirmware.org
> <mailto:mbed-tls@lists.trustedfirmware.org>
>
> •
>
>
>
> psa-crypto(a)lists.trustedfirmware.org
> <mailto:psa-crypto@lists.trustedfirmware.org>
>
> •
>
>
>
> dave.rodgman(a)arm.com <mailto:dave.rodgman@arm.com>
>
> *more details »
> <https://www.google.com/calendar/event?action=VIEW&eid=NHVvY2FxY2o4Njk3MWZkd…>***
>
> Hi,
> Trustedfirmware.org community project would like to invite you to the
> Mbed TLS Virtual Workshop.
>
> The purpose of the workshop is to bring together the Mbed TLS
> community including maintainers, contributors and users to discuss
>
> * The future direction of the project and
> * Ways to improve community collaboration
>
> Here is the agenda for the workshop.
>
> *Topic Time (in GMT)*
> Welcome 2.00 - 2.10pm
> Constant-time code 2.10 – 2.30pm
> Processes - how does work get scheduled? 2.30 – 2.50pm
> PSA Crypto APIs 2.50 – 3.20pm
> PSA Crypto for Silicon Labs Wireless
> MCUs - Why, What, Where and When 3.20 – 3.50pm
>
> *Break *
>
> Roadmap, TLS1.3 Update 4.10 – 4.30pm
> Mbed TLS 3.0 Plans, Scope 4.30 – 5.00pm
> How do I contribute my first review
> and be an effective Mbed TLS reviewer 5.00 – 5.30pm
>
> Regards,
>
> Don Harbin
> Trusted Firmware Community Manager
>
>
> ==============Zoom details below:====================
> Trusted Firmware is inviting you to a scheduled Zoom meeting.
>
> Topic: Mbed TLS Virtual Workshop
> Time: Nov 3, 2020 02:00 PM Greenwich Mean Time
>
> Join Zoom Meeting
> https://linaro-org.zoom.us/j/95315200315?pwd=ZDJGc1BZMHZLV29DTmpGUllmMjB1UT…
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>
> Meeting ID: 953 1520 0315
> Passcode: 143755
> One tap mobile
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>
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>
Hi,
Thank you Gilles for the detailed reply.
Do you prefer that discussion about PSA Crypto API spec go on mailing
list instead of here ? Is there some room for evolution or is the spec
already in a frozen released state ?
For new algorithms, it's of course preferable that they're defined in
the spec itself. But does the mbedtls project want to supports all
algorithms that will be used with PSA Crypto API ?
For pure ED25519 and ED448 with scattered data, there's one big gotcha.
You need to generate twice a hash that includes the message. Thus the
implementation needs to be able to access the buffers of the message
twice. With a piece of the message given only once as in the
init-update-finish scheme, that does not work well.
From reading the document on the PSA Crypto driver API, a transparent
driver benefits from the management of keys done by the mbedtls
implementation. But what benefit is there for a driver working with
opaque keys which has to fully handle the protections and restrictions
of keys internally ?
Best,
François.
On 11/2/20 11:01 PM, Gilles Peskine via mbed-tls wrote:
> Hello,
>
> Thank you for your interest in the PSA crypto API.
>
> On 28/10/2020 15:20, François Beerten via mbed-tls wrote:
>> Hi everybody,
>>
>> After reading the PSA Crypto API specs (as on
>> https://armmbed.github.io/mbed-crypto/html/overview/functionality.html)
>> and looking at the mbed TLS library, a few questions came up.
>>
>> Is there some repository with the sources of the PSA Crypto API specs
>> where one can follow the evolution and eventually send proposals and
>> patches ?
>>
> The PSA specification drafts are not public. You can send feedback about
> the PSA Crypto application and driver interfaces on the psa-crypto
> mailing list (psa-crypto(a)lists.trustedfirmware.org,
> https://lists.trustedfirmware.org/mailman/listinfo/psa-crypto). If you
> prefer to send confidential feedback, you can email mbed-crypto(a)arm.com
> (feedback at this address will only be discussed inside Arm). An issue
> in the Mbed TLS repository will also reach PSA Crypto architects.
>
>> A note says "Hash suspend and resume is not defined for the SHA3
>> family of hash algorithms". Why are they not defined for SHA3 ?
>>
> The hash suspend/resume operations marshall the internal state of the
> hash operation. They mimic an existing JavaCard API
> (https://docs.oracle.com/javacard/3.0.5/api/javacard/security/InitializedMes…).
> There is a de facto standard representation of the internal state for
> common Merkle-Damgård constructions, which covers all the currently
> defined hash algorithms except SHA3. If there's interest in this
> functionality, we could standardize a representation for SHA3.
>
>> How can or should one add support in PSA Crypto AP for not yet defined
>> algorithms (for example a KDF) ?
>>
> Answer from a PSA Crypto architect: preferably by requesting an encoding
> for this KDF as a PSA_ALG_xxx value (as well as new
> PSA_KEY_DERIVATION_INPUT_xxx values if applicable). If you can't do
> that, use an encoding in the vendor range (most significant bit set).
>
> The world of key derivation functions is unfortunately messy: there are
> many similar, but not functionally equivalent constructions (such as
> hashing a secret together with a nonce, formatted in all kinds of
> different ways). The set of KDF in PSA Crypto 1.0.0 was the minimum set
> required for the TLS protocol. We expect 1.0.x updates to define more
> KDF algorithms.
>
> Answer from an Mbed TLS maintainer: contributing an implementation would
> be appreciated (but not required).
>
>> In multipart operations, can the user reuse the input buffers
>> immediately after doing an 'update' (for example after
>> psa_hash_update()) ? And can he reuse the input buffers immediately
>> after some "setup" functions like psa_cipher_set_iv() or
>> psa_aead_set_nonce() ?
>>
> Yes. PSA crypto API functions that take a buffer as a parameter never
> take ownership of that buffer. Once the function returns, you can do
> whatever you want with the buffer.
>
> The PSA specification even guarantees that you can use the same buffer,
> or overlapping buffers, as inputs and outputs to the same function call.
> However beware that the Mbed TLS implementation does not always support
> such overlap (https://github.com/ARMmbed/mbedtls/issues/3266).
>
>> Do you plan to support (pure) ED25519 and ED448 only via
>> psa_sign_message() and psa_verify_message() ? What about messages in
>> multiple chunks ?
>>
> We plan to add a multi-part message signature interface, both for the
> sake of pureEdDSA and suitable for Mbed TLS's restartable ECDSA. I
> expect the design to be “what you'd expect” but I haven't yet verified
> that there aren't any gotchas.
>
>> In psa_asymmetric_encrypt(), why is the salt provided explicitely.
>> Shouldn't it be generated randomly internally when needed ?
>>
> Some applications use a fixed or deterministic salt which they check on
> decryption. Note that this parameter is what PKCS#1 calls “label”.
>
>> With PSA Crypto API, you define a flexible API for cryptographic
>> operations. Apparently, other providers could make their own
>> implementation of PSA Crypto API. Will mbed TLS then be able to use
>> those alternate PSA Crypto API implementations ? How would that work
>> practically ?
>>
> The X.509 and TLS layer of Mbed TLS are currently designed to use the
> mbedtls_xxx crypto API. We have already added partial support for the
> psa_xxx crypto API (with MBEDTLS_USE_PSA_CRYPTO), however it is not yet
> possible to fully decouple the X.509/TLS layers from the Mbed TLS crypto
> implementation. (I think this is already possible for a small set of
> cipher suites, but it isn't something that we've tried or currently
> actively support.) Before this can happen, some Mbed TLS APIs need to
> change, which will happen in 2021 with Mbed TLS 3.0. After that, we plan
> to decouple the PSA crypto reference implementation (Mbed TLS's current
> crypto implementation) from the X.509/TLS layer (which will remain “Mbed
> TLS”). Our plans
> (https://developer.trustedfirmware.org/w/mbed-tls/roadmap/) that far
> into the future are still vague and may change.
>
> Note that for the most common case of wanting a different implementation
> of cryptography, which is to leverage hardware such as accelerators and
> secure elements, PSA is defining a driver interface which is currently
> being implemented in Mbed TLS
> (https://github.com/ARMmbed/mbedtls/blob/development/docs/proposed/psa-drive…).
> The driver interface lets you combine mechanisms supported by your
> hardware with Mbed TLS's implementation for mechanisms without hardware
> support.
>
Hi Mate,
I had a look and I couldn’t find such a feature implemented either. I don’t think that Mbed TLS supports that at the moment.
Best regards,
Janos
From: mbed-tls <mbed-tls-bounces(a)lists.trustedfirmware.org> on behalf of "Z.Máté via mbed-tls" <mbed-tls(a)lists.trustedfirmware.org>
Reply to: "Z.Máté" <enleszekakalozkiraly(a)gmail.com>
Date: Monday, 2 November 2020 at 21:01
To: "mbed-tls(a)lists.trustedfirmware.org" <mbed-tls(a)lists.trustedfirmware.org>
Subject: [mbed-tls] Write private key into buffer using encrypted PEM format
Dear mbedtls list members!
Sorry if this is the second time I ask, I'm not sure the previous question is still on the list.
I'm asking if there's a way to export a private key into a buffer in an encrypted format. So that mbedtls_pk_parse_key() has to be called with a password.
In the example program key_app.c (I hope that's how it's called) I can see there are password encrypted PEM formatted keys. But how to generate one?
For clarity, this is the type of header I'm looking for.
—–BEGIN RSA PRIVATE KEY—–
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-256-CBC,AB8E2B5B2D989271273F6730B6F9C687
……………………………………………….
……………………………………………….
………………………………………
—–END RSA PRIVATE KEY—–
I was only able to generate something like this by, using command line openssl. But I'd like a better solution, in code, using mbedtls.
Yours
Zombor Máté
Hello,
Thank you for your interest in the PSA crypto API.
On 28/10/2020 15:20, François Beerten via mbed-tls wrote:
>
> Hi everybody,
>
> After reading the PSA Crypto API specs (as on
> https://armmbed.github.io/mbed-crypto/html/overview/functionality.html)
> and looking at the mbed TLS library, a few questions came up.
>
> Is there some repository with the sources of the PSA Crypto API specs
> where one can follow the evolution and eventually send proposals and
> patches ?
>
The PSA specification drafts are not public. You can send feedback about
the PSA Crypto application and driver interfaces on the psa-crypto
mailing list (psa-crypto(a)lists.trustedfirmware.org,
https://lists.trustedfirmware.org/mailman/listinfo/psa-crypto). If you
prefer to send confidential feedback, you can email mbed-crypto(a)arm.com
(feedback at this address will only be discussed inside Arm). An issue
in the Mbed TLS repository will also reach PSA Crypto architects.
> A note says "Hash suspend and resume is not defined for the SHA3
> family of hash algorithms". Why are they not defined for SHA3 ?
>
The hash suspend/resume operations marshall the internal state of the
hash operation. They mimic an existing JavaCard API
(https://docs.oracle.com/javacard/3.0.5/api/javacard/security/InitializedMes…).
There is a de facto standard representation of the internal state for
common Merkle-Damgård constructions, which covers all the currently
defined hash algorithms except SHA3. If there's interest in this
functionality, we could standardize a representation for SHA3.
> How can or should one add support in PSA Crypto AP for not yet defined
> algorithms (for example a KDF) ?
>
Answer from a PSA Crypto architect: preferably by requesting an encoding
for this KDF as a PSA_ALG_xxx value (as well as new
PSA_KEY_DERIVATION_INPUT_xxx values if applicable). If you can't do
that, use an encoding in the vendor range (most significant bit set).
The world of key derivation functions is unfortunately messy: there are
many similar, but not functionally equivalent constructions (such as
hashing a secret together with a nonce, formatted in all kinds of
different ways). The set of KDF in PSA Crypto 1.0.0 was the minimum set
required for the TLS protocol. We expect 1.0.x updates to define more
KDF algorithms.
Answer from an Mbed TLS maintainer: contributing an implementation would
be appreciated (but not required).
> In multipart operations, can the user reuse the input buffers
> immediately after doing an 'update' (for example after
> psa_hash_update()) ? And can he reuse the input buffers immediately
> after some "setup" functions like psa_cipher_set_iv() or
> psa_aead_set_nonce() ?
>
Yes. PSA crypto API functions that take a buffer as a parameter never
take ownership of that buffer. Once the function returns, you can do
whatever you want with the buffer.
The PSA specification even guarantees that you can use the same buffer,
or overlapping buffers, as inputs and outputs to the same function call.
However beware that the Mbed TLS implementation does not always support
such overlap (https://github.com/ARMmbed/mbedtls/issues/3266).
> Do you plan to support (pure) ED25519 and ED448 only via
> psa_sign_message() and psa_verify_message() ? What about messages in
> multiple chunks ?
>
We plan to add a multi-part message signature interface, both for the
sake of pureEdDSA and suitable for Mbed TLS's restartable ECDSA. I
expect the design to be “what you'd expect” but I haven't yet verified
that there aren't any gotchas.
> In psa_asymmetric_encrypt(), why is the salt provided explicitely.
> Shouldn't it be generated randomly internally when needed ?
>
Some applications use a fixed or deterministic salt which they check on
decryption. Note that this parameter is what PKCS#1 calls “label”.
> With PSA Crypto API, you define a flexible API for cryptographic
> operations. Apparently, other providers could make their own
> implementation of PSA Crypto API. Will mbed TLS then be able to use
> those alternate PSA Crypto API implementations ? How would that work
> practically ?
>
The X.509 and TLS layer of Mbed TLS are currently designed to use the
mbedtls_xxx crypto API. We have already added partial support for the
psa_xxx crypto API (with MBEDTLS_USE_PSA_CRYPTO), however it is not yet
possible to fully decouple the X.509/TLS layers from the Mbed TLS crypto
implementation. (I think this is already possible for a small set of
cipher suites, but it isn't something that we've tried or currently
actively support.) Before this can happen, some Mbed TLS APIs need to
change, which will happen in 2021 with Mbed TLS 3.0. After that, we plan
to decouple the PSA crypto reference implementation (Mbed TLS's current
crypto implementation) from the X.509/TLS layer (which will remain “Mbed
TLS”). Our plans
(https://developer.trustedfirmware.org/w/mbed-tls/roadmap/) that far
into the future are still vague and may change.
Note that for the most common case of wanting a different implementation
of cryptography, which is to leverage hardware such as accelerators and
secure elements, PSA is defining a driver interface which is currently
being implemented in Mbed TLS
(https://github.com/ARMmbed/mbedtls/blob/development/docs/proposed/psa-drive…).
The driver interface lets you combine mechanisms supported by your
hardware with Mbed TLS's implementation for mechanisms without hardware
support.
--
Gilles Peskine
PSA Cryptography architect and Mbed TLS developer
> Thank you for your attention,
>
> François.
>
>
>
Dear mbedtls list members!
Sorry if this is the second time I ask, I'm not sure the previous question
is still on the list.
I'm asking if there's a way to export a private key into a buffer in an
encrypted format. So that mbedtls_pk_parse_key() has to be called with a
password.
In the example program key_app.c (I hope that's how it's called) I can see
there are password encrypted PEM formatted keys. But how to generate one?
For clarity, this is the type of header I'm looking for.
—–BEGIN RSA PRIVATE KEY—–
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-256-CBC,AB8E2B5B2D989271273F6730B6F9C687
……………………………………………….
……………………………………………….
………………………………………
—–END RSA PRIVATE KEY—–
I was only able to generate something like this by, using command line
openssl. But I'd like a better solution, in code, using mbedtls.
Yours
Zombor Máté
Hi All,
Gentle reminder about the Mbed TLS workshop tomorrow (Tuesday, November 3rd) from 2 to 6pm GMT.
See agenda and zoom link here - https://www.trustedfirmware.org/meetings/mbed-tls-workshop/
Thanks,
Shebu
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Sent: Friday, October 23, 2020 12:32 AM
To: Trusted Firmware Public Meetings; Shebu Varghese Kuriakose; mbed-tls(a)lists.trustedfirmware.org; Don Harbin; psa-crypto(a)lists.trustedfirmware.org; Dave Rodgman
Subject: Mbed TLS Virtual Workshop
When: Tuesday, November 3, 2020 2:00 PM-6:00 PM (UTC+00:00) Dublin, Edinburgh, Lisbon, London.
Where: Zoom: https://linaro-org.zoom.us/j/95315200315?pwd=ZDJGc1BZMHZLV29DTmpGUllmMjB1UT…
You have been invited to the following event.
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When
Tue Nov 3, 2020 7am – 11am Mountain Standard Time - Phoenix
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Zoom: https://linaro-org.zoom.us/j/95315200315?pwd=ZDJGc1BZMHZLV29DTmpGUllmMjB1UT… (map<https://www.google.com/maps/search/Zoom:+https:%2F%2Flinaro-org.zoom.us%2Fj…>)
Calendar
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•
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•
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more details »<https://www.google.com/calendar/event?action=VIEW&eid=NHVvY2FxY2o4Njk3MWZkd…>
Hi,
Trustedfirmware.org community project would like to invite you to the Mbed TLS Virtual Workshop.
The purpose of the workshop is to bring together the Mbed TLS community including maintainers, contributors and users to discuss
* The future direction of the project and
* Ways to improve community collaboration
Here is the agenda for the workshop.
Topic Time (in GMT)
Welcome 2.00 - 2.10pm
Constant-time code 2.10 – 2.30pm
Processes - how does work get scheduled? 2.30 – 2.50pm
PSA Crypto APIs 2.50 – 3.20pm
PSA Crypto for Silicon Labs Wireless
MCUs - Why, What, Where and When 3.20 – 3.50pm
Break
Roadmap, TLS1.3 Update 4.10 – 4.30pm
Mbed TLS 3.0 Plans, Scope 4.30 – 5.00pm
How do I contribute my first review
and be an effective Mbed TLS reviewer 5.00 – 5.30pm
Regards,
Don Harbin
Trusted Firmware Community Manager
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Dear mbedtls list members!
Is there a way to write a private key into a buffer, in PEM format, by
using a password for encryption? Mbedtls is able to parse encrypted PEM
files so can I write one? I couldn't really find any info regarding it,
only an older, unfinished github issue ...
Yours
Zombor Máté
Hello François,
The following is my understanding, I am not a maintainer but a user of
mbedtls. My response below only addresses a few of your questions.
PSA appears to be bound to what mbedtls currently supports, this does not
include Ed25519 or Ed448 at this time. A pull request is currently open for
this feature development https://github.com/ARMmbed/mbedtls/pull/3245
Further development may be necessary to include those in PSA.
The only implementation of PSA that I know of is one that wraps around
mbedtls.
Best,
Levi
On Wed, Oct 28, 2020 at 9:20 AM François Beerten via mbed-tls <
mbed-tls(a)lists.trustedfirmware.org> wrote:
> Hi everybody,
>
> After reading the PSA Crypto API specs (as on
> https://armmbed.github.io/mbed-crypto/html/overview/functionality.html)
> and looking at the mbed TLS library, a few questions came up.
>
> Is there some repository with the sources of the PSA Crypto API specs
> where one can follow the evolution and eventually send proposals and
> patches ?
>
> A note says "Hash suspend and resume is not defined for the SHA3 family of
> hash algorithms". Why are they not defined for SHA3 ?
>
> How can or should one add support in PSA Crypto AP for not yet defined
> algorithms (for example a KDF) ?
>
> In multipart operations, can the user reuse the input buffers immediately
> after doing an 'update' (for example after psa_hash_update()) ? And can
> he reuse the input buffers immediately after some "setup" functions like
> psa_cipher_set_iv() or psa_aead_set_nonce() ?
>
> Do you plan to support (pure) ED25519 and ED448 only via
> psa_sign_message() and psa_verify_message() ? What about messages in
> multiple chunks ?
>
> In psa_asymmetric_encrypt(), why is the salt provided explicitely.
> Shouldn't it be generated randomly internally when needed ?
>
> With PSA Crypto API, you define a flexible API for cryptographic
> operations. Apparently, other providers could make their own implementation
> of PSA Crypto API. Will mbed TLS then be able to use those alternate PSA
> Crypto API implementations ? How would that work practically ?
>
> Thank you for your attention,
>
> François.
>
>
> --
> mbed-tls mailing list
> mbed-tls(a)lists.trustedfirmware.org
> https://lists.trustedfirmware.org/mailman/listinfo/mbed-tls
>
I make a CA certificate for JITR using BouncyCastle lib in the android app as the below example
And a device certificate is generated by this certificate in mbed_tls. At this time, JITR is not working.
Namely, a device certificate is not registered in AWS.
But In the case of making a ca certificate using OPENSSL, JITR works normally.
Below is CA certificate based BouncyCastle lib.
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
-----BEGIN EC PRIVATE KEY-----
MIGTAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBHkwdwIBAQQgU9pUZUfplZyhC+mH
Pt8pthLItdpbJ+Qy47r7gJKTNvCgCgYIKoZIzj0DAQehRANCAARJJ2HaiNwnVZZj
JE5qikutx5x3OT28gX39UaJBhujROs99YpQPGLdnxhRyJZ9ZELcf/+rLQQNWyKoq
rEqPMGne
-----END EC PRIVATE KEY-----
BRs.
Hyunung Park
Hi everybody,
After reading the PSA Crypto API specs (as on
https://armmbed.github.io/mbed-crypto/html/overview/functionality.html)
and looking at the mbed TLS library, a few questions came up.
Is there some repository with the sources of the PSA Crypto API specs
where one can follow the evolution and eventually send proposals and
patches ?
A note says "Hash suspend and resume is not defined for the SHA3 family
of hash algorithms". Why are they not defined for SHA3 ?
How can or should one add support in PSA Crypto AP for not yet defined
algorithms (for example a KDF) ?
In multipart operations, can the user reuse the input buffers
immediately after doing an 'update' (for example after
psa_hash_update()) ? And can he reuse the input buffers immediately
after some "setup" functions like psa_cipher_set_iv() or
psa_aead_set_nonce() ?
Do you plan to support (pure) ED25519 and ED448 only via
psa_sign_message() and psa_verify_message() ? What about messages in
multiple chunks ?
In psa_asymmetric_encrypt(), why is the salt provided explicitely.
Shouldn't it be generated randomly internally when needed ?
With PSA Crypto API, you define a flexible API for cryptographic
operations. Apparently, other providers could make their own
implementation of PSA Crypto API. Will mbed TLS then be able to use
those alternate PSA Crypto API implementations ? How would that work
practically ?
Thank you for your attention,
François.
Hi Frank,
The issue exists because you are downloading a tag and not the release. The 2.16.8 release is available here:
https://github.com/ARMmbed/mbedtls/archive/v2.16.8.tar.gz
Best regards,
Janos
On 28/10/2020, 12:15, "mbed-tls on behalf of Frank Bergmann via mbed-tls" <mbed-tls-bounces(a)lists.trustedfirmware.org on behalf of mbed-tls(a)lists.trustedfirmware.org> wrote:
Hi Gilles,
I noticed that the "double name" does still exist in some archive files:
$ wget -q -O - https://github.com/ARMmbed/mbedtls/archive/mbedtls-2.16.8.tar.gz|tar tzf -|head
mbedtls-mbedtls-2.16.8/
mbedtls-mbedtls-2.16.8/.github/
mbedtls-mbedtls-2.16.8/.github/issue_template.md
mbedtls-mbedtls-2.16.8/.github/pull_request_template.md
mbedtls-mbedtls-2.16.8/.gitignore
mbedtls-mbedtls-2.16.8/.globalrc
mbedtls-mbedtls-2.16.8/.pylintrc
mbedtls-mbedtls-2.16.8/.travis.yml
mbedtls-mbedtls-2.16.8/CMakeLists.txt
mbedtls-mbedtls-2.16.8/CONTRIBUTING.md
cheers,
Frank
On Tue, Aug 04, 2020 at 09:18:56PM +0000, Gilles Peskine via mbed-tls wrote:
[...]
> The naming with mbedtls-mbedtls- must be a bug in our release script.
[...]
--
Frank Bergmann, Pödinghauser Str. 5, D-32051 Herford, Tel. +49-5221-9249753
SAP Hybris & Linux LPIC-3, E-Mail tx2014(a)tuxad.de, USt-IdNr DE237314606
http://tdyn.de/freel -- Redirect to profile at freelancermap
http://www.gulp.de/freiberufler/2HNKY2YHW.html -- Profile at GULP
--
mbed-tls mailing list
mbed-tls(a)lists.trustedfirmware.org
https://lists.trustedfirmware.org/mailman/listinfo/mbed-tls
Hi Gilles,
I noticed that the "double name" does still exist in some archive files:
$ wget -q -O - https://github.com/ARMmbed/mbedtls/archive/mbedtls-2.16.8.tar.gz|tar tzf -|head
mbedtls-mbedtls-2.16.8/
mbedtls-mbedtls-2.16.8/.github/
mbedtls-mbedtls-2.16.8/.github/issue_template.md
mbedtls-mbedtls-2.16.8/.github/pull_request_template.md
mbedtls-mbedtls-2.16.8/.gitignore
mbedtls-mbedtls-2.16.8/.globalrc
mbedtls-mbedtls-2.16.8/.pylintrc
mbedtls-mbedtls-2.16.8/.travis.yml
mbedtls-mbedtls-2.16.8/CMakeLists.txt
mbedtls-mbedtls-2.16.8/CONTRIBUTING.md
cheers,
Frank
On Tue, Aug 04, 2020 at 09:18:56PM +0000, Gilles Peskine via mbed-tls wrote:
[...]
> The naming with mbedtls-mbedtls- must be a bug in our release script.
[...]
--
Frank Bergmann, Pödinghauser Str. 5, D-32051 Herford, Tel. +49-5221-9249753
SAP Hybris & Linux LPIC-3, E-Mail tx2014(a)tuxad.de, USt-IdNr DE237314606
http://tdyn.de/freel -- Redirect to profile at freelancermap
http://www.gulp.de/freiberufler/2HNKY2YHW.html -- Profile at GULP
Hi Sawyer,
Thank you for your interest in Mbed TLS. Currently the status of these CVE’s is:
- CVE-2020-16150 has been fixed in the latest Mbed TLS release
- CVE-2018-1000520 is not a security issue, it had been studied and rejected
- CVE-2016-3739 is a vulnerability in an application using Mbed TLS but not in Mbed TLS itself, also it too had been fixed.
Does this answer your question?
(Also, I would like to make a minor clarification: we are not Arm Support. As far as I know Arm does not offer official support for Mbed TLS. Arm only contributes engineers to the Mbed TLS project, and at the moment these engineers are the maintainers of Mbed TLS. We are on this mailing list and try to answer questions, but we are not doing that as official support provided by Arm, but as members of the community. Mbed TLS is supported by the community and this mailing list is indeed the right place to get that support. I apologise for the nitpick, I just wanted to make sure that we are not giving the wrong impressions.)
Best regards,
Janos
(Mbed TLS developer)
From: mbed-tls <mbed-tls-bounces(a)lists.trustedfirmware.org> on behalf of Sawyer Liu via mbed-tls <mbed-tls(a)lists.trustedfirmware.org>
Reply to: Sawyer Liu <sawyer.liu(a)nxp.com>
Date: Wednesday, 28 October 2020 at 01:59
To: "mbed-tls(a)lists.trustedfirmware.org" <mbed-tls(a)lists.trustedfirmware.org>
Subject: [mbed-tls] About mbedtls CVE
Hello ARM Support,
About below CVEs, any update? Thanks.
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-16150<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcve.mitre…>
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-1000520https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3739
Best Regards
Sawyer Liu
Microcontrollers, NXP Semiconductors
From: 박현웅 <hupark(a)ictk.com>
Sent: Wednesday, October 28, 2020 6:21 PM
To: 'mbed-tls(a)lists.trustedfirmware.org.' <mbed-tls(a)lists.trustedfirmware.org.>
Subject: JITR in mbedtls
Hi
I make a certificate using BouncyCastle lib in android app as the below.
JITR is not working.
Namely a device certificate is not registered in aws iot.
In case of making ca certificate using openssl, JITR works normally.
Could you please help me?
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
-----BEGIN EC PRIVATE KEY-----
MIGTAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBHkwdwIBAQQgU9pUZUfplZyhC+mH
Pt8pthLItdpbJ+Qy47r7gJKTNvCgCgYIKoZIzj0DAQehRANCAARJJ2HaiNwnVZZj
JE5qikutx5x3OT28gX39UaJBhujROs99YpQPGLdnxhRyJZ9ZELcf/+rLQQNWyKoq
rEqPMGne
-----END EC PRIVATE KEY-----
BRs.
Hyunung Park
Hi Fabian,
Unfortunately https://tls.mbed.org/how-to-get is out of date. As
indicated on https://tls.mbed.org/download, newer releases (since 2.17)
are distributed under Apache license only. Only the long-time support
branches (2.7.x and 2.16.x) still have GPL releases.
--
Gilles Peskine
Mbed TLS developer
On 20/10/2020 14:19, Fabian Keil via mbed-tls wrote:
> Hi,
>
> tls.mbed.org currently sends mixed signals regarding
> the license of future MbedTLS releases.
>
> Quoting https://tls.mbed.org/download:
> | In packaged form, mbed TLS 2.1.0 to mbed TLS 2.16 are
> | available in both an Apache 2.0 licensed version (our
> | primary open source license) and in a GPL 2.0 licensed version.
> |
> | Newer versions will be available under the Apache 2.0 license.
>
> Quoting https://tls.mbed.org/how-to-get:
> | All the current versions of the mbed TLS library are distributed
> | under the Apache 2.0 license and available from our Download area.
> | In addition there are packaged versions of the mbed TLS library
> | that are distributed with the GNU Public License Version 2.0 (GPL v2.0).
> |
> | The Apache-licensed and GPL-licensed versions of mbed TLS are
> | identical in source code (with the exception of the license
> | headers at the top of files).
> |
> | We plan to keep both licensed versions around.
>
> Can anyone estimate when "newer releases" will no longer
> be dual licensed?
>
> We recently added MbedTLS support for Privoxy and a
> MbedTLS license switch from dual license to Apache 2.0
> complicates the license terms.
>
> Thanks
> Fabian
>
Hi Máté,
On 26/10/2020 12:04, Z.Máté via mbed-tls wrote:
> Dear mbedtls mailing list members!
>
> I hope you recieve my message now, previously I had problems posting
> to this list. :(
>
> My first question is actually about the PEM format. As far as I'm
> aware the PEM format either contains the Private key (signalled by the
> ---- BEGIN PRIVATE KEY ---- header) or a public key (---- BEGIN PUBLIC
> KEY -----). In my application I have to work on an app that stores key
> pairs in a special, secure storage solution (Secure Storage of OPTEE
> if you've heard about it). I decided to export the keys in PEM format,
> so that reading and handling them is equal to moving a large string
> buffer around. Using the PEM format, is there a way to store both
> private and public keys in the same "file"? Does mbedtls allow for
> such a solution (does such a solution even exist?).
There are actually several PEM formats. Some private key formats
actually store both the private key and the public key, while others
only store the private key. However, it is always possible to calculate
the public key from the private key. So if you want to have the whole
key pair, just write the private key in any format.
If you have a private key file, you can extract the public key with the
Mbed TLS sample program key_app_writer (untested command line, typed
directly into my mail client):
programs/pkey/key_app_writer mode=private filename=my_private_key.pem
output_mode=public output_file=my_public_key.pem
or with OpenSSL:
openssl pkey -in my_private_key.pem -pubout -out my_public_key.pem
>
> If not, is there a simple way to get the public key from a private key
> object? Does the mbedtls_pk_context, (that parsed up with a private
> key) contain the information needed to export the public key into a
> PEM buffer? As far as I know mbedtls allows for exporting the private
> key and the public key with the functions mbedtls_write_key_pem and
> ...write_pubkey_pem (or something along those lines) does that mean I
> can only export one at a time and there's no way to save the
> information for both into one PEM buffer?
>
> If there's a way to save both private and public keys into one PEM
> file, do I have to parse the private key and public key into separate
> objects then? With parse_key and parse_pubkey? This isn't really a
> problem just clarifying.
Once you have an mbedtls_pk_context, if you want to export both keys to
a file, use mbedtls_write_key_pem(). If you want to have a separate file
that only contains the public key, call mbedtls_write_pubkey_pem() on
the same mbedtls_pk_context.
>
> If you can point me to an actually good description of the PEM format
> and what CAN be stored inside of it, I'd be very grateful! :)
PEM is just an encoding: base64 data between a header and footer. The
base64-encoded data can have several different formats depending on the
header. It can represent a private key (several formats depending on the
header), a public key or a certificate. A complete description is spread
across about half a dozen RFC. Fortunately, I don't think you need to
dig into those.
>
> I also have a question regarding the example SSL server program. In
> it, the server needs a private key and a certificate for obvious
> reasons. It also loads a certificate and as far as I know, the
> certificate has to be tied to a known CA for it to be valid.
>
> I would like to test the program with a self generated key pair, do I
> need to change the Certificate and CAs to a new one as well? To
> authenticate the new keypair? Does the mbedtls ssl_client1 example
> program work with self signed certs? Or do I need to take care of the
> CA validation myself (that would probably beyond the scope of the
> project I'm working on).
The sample program ssl_server does not check the client certificate. The
test program ssl_server2 can check the client certificate: pass the
command line options "auth_mode=required ca_file=my_ca.crt". If you have
a self-signed client certificate, you can pass it as the ca_file.
--
Gilles Peskine
Mbed TLS developer
>
> Thank you in advance!
>
> Yours truly,
> Máté Zombor
>
Dear mbedtls mailing list members!
I hope you recieve my message now, previously I had problems posting to
this list. :(
My first question is actually about the PEM format. As far as I'm aware the
PEM format either contains the Private key (signalled by the ---- BEGIN
PRIVATE KEY ---- header) or a public key (---- BEGIN PUBLIC KEY -----). In
my application I have to work on an app that stores key pairs in a special,
secure storage solution (Secure Storage of OPTEE if you've heard about it).
I decided to export the keys in PEM format, so that reading and handling
them is equal to moving a large string buffer around. Using the PEM format,
is there a way to store both private and public keys in the same "file"?
Does mbedtls allow for such a solution (does such a solution even exist?).
If not, is there a simple way to get the public key from a private key
object? Does the mbedtls_pk_context, (that parsed up with a private key)
contain the information needed to export the public key into a PEM buffer?
As far as I know mbedtls allows for exporting the private key and the
public key with the functions mbedtls_write_key_pem and ...write_pubkey_pem
(or something along those lines) does that mean I can only export one at a
time and there's no way to save the information for both into one PEM
buffer?
If there's a way to save both private and public keys into one PEM file, do
I have to parse the private key and public key into separate objects then?
With parse_key and parse_pubkey? This isn't really a problem just
clarifying.
If you can point me to an actually good description of the PEM format and
what CAN be stored inside of it, I'd be very grateful! :)
I also have a question regarding the example SSL server program. In it, the
server needs a private key and a certificate for obvious reasons. It also
loads a certificate and as far as I know, the certificate has to be tied to
a known CA for it to be valid.
I would like to test the program with a self generated key pair, do I need
to change the Certificate and CAs to a new one as well? To authenticate the
new keypair? Does the mbedtls ssl_client1 example program work with self
signed certs? Or do I need to take care of the CA validation myself (that
would probably beyond the scope of the project I'm working on).
Thank you in advance!
Yours truly,
Máté Zombor
You have been invited to the following event.
Title: Mbed TLS Virtual Workshop
Hi,Trustedfirmware.org community project would like to invite you to the
Mbed TLS Virtual Workshop. The purpose of the workshop is to bring
together the Mbed TLS community including maintainers, contributors and
users to discussThe future direction of the project andWays to improve
community collaborationHere is the agenda for the workshop.Topic
Time (in GMT)Welcome
2.00 - 2.10pmConstant-time code
2.10
– 2.30pmProcesses - how does work get scheduled? 2.30 –
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2.50 –
3.20pmPSA Crypto for Silicon Labs Wireless MCUs
- Why, What, Where and When 3.20 –
3.50pmBreak
Roadmap,
TLS1.3 Update
4.10
– 4.30pmMbed TLS 3.0 Plans, Scope
4.30 – 5.00pmHow do I contribute my first review
and be an effective Mbed TLS reviewer
5.00 – 5.30pmRegards,Don Harbin Trusted Firmware Community
Manager==============Zoom details below:====================Trusted
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Hi,
tls.mbed.org currently sends mixed signals regarding
the license of future MbedTLS releases.
Quoting https://tls.mbed.org/download:
| In packaged form, mbed TLS 2.1.0 to mbed TLS 2.16 are
| available in both an Apache 2.0 licensed version (our
| primary open source license) and in a GPL 2.0 licensed version.
|
| Newer versions will be available under the Apache 2.0 license.
Quoting https://tls.mbed.org/how-to-get:
| All the current versions of the mbed TLS library are distributed
| under the Apache 2.0 license and available from our Download area.
| In addition there are packaged versions of the mbed TLS library
| that are distributed with the GNU Public License Version 2.0 (GPL v2.0).
|
| The Apache-licensed and GPL-licensed versions of mbed TLS are
| identical in source code (with the exception of the license
| headers at the top of files).
|
| We plan to keep both licensed versions around.
Can anyone estimate when "newer releases" will no longer
be dual licensed?
We recently added MbedTLS support for Privoxy and a
MbedTLS license switch from dual license to Apache 2.0
complicates the license terms.
Thanks
Fabian
Hi Dave,
Thanks for your reply.
The particular reasons for bringing up 2.7 and 2.16 first is that my
employer is currently using 2.7 and would prefer using a small increment.
Having said that, if adding features to LTS is not advisable (especially
given that 2.7 has less than 6 months of projected life), I think I can
present the arguments against using the 2.7.
Additional consideration is the timing. My employer needs fragmentation
support as soon as possible, with the intent of running it on a desktop
environment. Historically, when the engineers are able to provide my
employer with what is needed now, they are allowed more time for
incremental improvements.
The third consideration involves the MPS project by Hanno Becker. I've been
collaborating with Hanno, and with Hannes Tschofenig and Thomas Fosetti on
the project of adding QUIC support to mbedTLS. This goal depends on TLS 1.3
support (Hannes has written a prototype, which I was able to add QUIC in an
internal version), and on MPS. I would like to avoid putting a duplicate
effort into non-MPS fragmentation support.
Unfortunately, if I want to meet the timing requirements of my employer, I
will not be able to use MPS, since it needs more maturing.
Because of the above considerations, I would like to suggest the following
plan of actions:
As the first step, I would like to add the MVP (minimal viable product)
fragmentation to the development version. The MVP takes the following
assumptions:
1. The RAM footprint is not a concern for the MVP (my employer is going
to run it in the desktop environment).
2. Unification of the fragmentation between TLS and DTLS is not a
concern for the MVP
3. LTS is not a concern for the MVP (potentially not at all)
Because of the above simplifying assumptions, I believe that the change can
be small and focused. I think I can have code ready for review in a couple
of weeks.
As the second step, I would like to put my effort into helping Hanno Becker
with his MPS system. Once sufficiently mature, the MPS will supersede the
MVP fragmentation, and will open the doors for adding support for QUIC. The
simplifying assumptions 1. (RAM) and 2. (TLS <=> DTLS) will be addressed by
MPS. Addressing the last assumption may not be required.
What are your thoughts?
On Wed, Oct 14, 2020 at 10:28 AM Dave Rodgman <dave.rodgman(a)arm.com> wrote:
> Hi Omer,
>
>
>
> Thanks for offering to help us with this feature.
>
>
>
> Normally, we wouldn’t add new features directly to an older branch, for a
> few reasons. 2.7 is quite old and is in fact only guaranteed to be
> supported until Feb 21, so it’s not the ideal place to spend effort on new
> features. Introducing new features here would also create the situation
> where 2.7 has features not in development, and vice-versa, creating an
> upgrade dilemma for users (unless we were to port the feature to all
> supported branches). And adding significant new features to LTS branches
> can always introduce some risk of destabilising it.
>
>
>
> So for these reasons, we would normally recommend targeting the
> development branch for new features (with backports only where there is a
> strong reason to do so), and then picking up the next stable release that
> contains the new feature.
>
>
>
> Is there a particular reason you’re focusing on 2.7, rather than
> development, or would it be viable for you to add this to development and
> pick up the next release?
>
>
>
> Thanks
>
>
>
> Dave
>
>
>
> *From: *mbed-tls <mbed-tls-bounces(a)lists.trustedfirmware.org> on behalf
> of Omer Shapira via mbed-tls <mbed-tls(a)lists.trustedfirmware.org>
> *Reply to: *Omer Shapira <omer.shapira(a)gmail.com>
> *Date: *Monday, 12 October 2020 at 20:04
> *To: *"mbed-tls(a)lists.trustedfirmware.org" <
> mbed-tls(a)lists.trustedfirmware.org>
> *Subject: *[mbed-tls] Working on TLS handshake record fragmentation
> (#1840)
>
>
>
> Hello,
>
> My employer (Facebook) is willing to give me some time to TLS handshake
> fragmentation support to MbedTLS 2.7 [0] . This would be my first
> contribution to MbedTLS, and I have several novice questions:
>
> 1. What is the best way to add the feature to MbedTLS 2.7?
> 2. Trade-off between the consistency of the fragmentation code across the
> branches, vs. the consistency of the branches.
>
>
> Question 1: Best way to add the feature to MbedTLS 2.7
>
> One constraint that I am facing is the code must be added to the upstream
> branch that is as close as possible to the 2.7.xx. My understanding of the
> Contribution Guidelines[1] is that while the LTS branches are mostly meant
> for the bug fixes, backporting of the new features is welcomed as long as
> the API/ABI compatibility is maintained and the disruption to the users is
> minimized.
>
> If adding support to the LTS branches is not advisable, are there any
> other possibilities of contributing the code to an upstream branch that is
> very close to the 2.7.xx?
>
> Question 2: Trade-off between the consistency of the fragmentation code
> across the branches, vs. the consistency of the branches.
>
> Assuming that adding features to 2.7 (and 2.16) *is* possible, there is a
> trade-off between the consistency of the fragmentation code across the
> branches, vs. the consistency of the branches. The `development` branch
> supports variable-length buffers[2] . Variable messages sizes would make
> the fragmentation easier in the development branch. In addition, there is
> the MPS effort by Hanno Becker which would make the fragmentation support
> even easier in the development branch. None of that is present in the 2.7
> or the 2.16 branches.
>
> What is the preferable trade-off in such a situation:
> a. Minimizing the change to the "host" version (2.7 or 2.16), on the
> expense the implementation of the feature differ between 2.7 and
> `development`, or
> b. Minimizing the differences in the implementation of the feature, on
> the expense of more intrusive changes to the earlier versions?
>
>
> [0] https://github.com/ARMmbed/mbedtls/issues/1840
> [1] https://github.com/ARMmbed/mbedtls/blob/development/CONTRIBUTING.md
> [2]
> https://github.com/ARMmbed/mbedtls/blob/development/include/mbedtls/config.…
>
> --
>
> Sincerely Yours,
> Omer Shapira
>
--
Sincerely Yours,
Omer Shapira
--
Sincerely Yours,
Omer Shapira