* Update to BearSSL 0.6+ release, add AES_CCM modes
Pull in latest BearSSL head (0.6 + minor additions) release and add AES_CCM
modes to the encryption options.
* Enable the aes_ccm initialization in client/server
* Initial attempt
* Working code with second stack thunking
* Remove #ifdefs in .S file, not needed.
* Clean up thunks and remove separate stack flag
* Fix PIO assembler errors
* Remove #ifdef code changes, ensure same code as PC
Remove "#ifdef ESP8266;...;#else;...;#endif" brackets in BearSSL to
ensure the host-tested code is the same as the ESP8266-run code.
* Move to latest BearSSL w/EC progmem savings
* Merge with master
* Add br_thunk_* calls to do ref counting, painting
Add reference counting br_thunk_add/del_ref() to replace stack handling code
in the class.
Add in stack painting and max usage calculation.
* Add in postmortem stack dump hooks
When a crash occurs while in the second stack, dump the BSSL stack and
then also the stack that it was called from (either cont or sys).
* Update stack dump to match decoder expectations
* Move thunk to code core for linkiage
The thunk code needs to be visible to the core routines, so move it to the
cores/esp8266 directory. Probably need to refactor the stack setup and the
bearssl portion to avoid dependency on bearssl libs in cores/esp8266
* Add 2nd stack dump utility routine
* Refactor once more, update stack size, add stress
Make stack_thunks generic, remove bearssl include inside of cores/esp8266.
Allocate the stack on a WiFiServerSecure object creation to avoid
fragmentation since we will need to allocate the stack to do any
connected work, anyway.
A stress test is now included which checks the total BearSSL second
stack usage for a variety of TLS handshake and certificate options
from badssl.org.
* Update to latest to-thunks branch
* Add BearSSL device test using stack stress
Run a series of SSL connection and transmission tests that stress
BearSSL and its stack usage to the device tests.
Modify device tests to include a possible SPIFFS generation and
upload when a make_spiffs.py file is present in a test directory.
* Use bearssl/master branch, not /to-thunks branch
Update to use the merged master branch of bearssl. Should have no code
changes.
BearSSLX509List, BearSSLSession, BearSSLPublicKey, and BearSSLPrivateKey
were all in the global namespace and not in the BearSSL:: one, due to an
oversight when they were originally created. Move them to the proper
namespace with the following mapping:
BearSSLX509List => BearSSL::X509List
BearSSLSession => BearSSL::Session
BearSSLPublicKey => BearSSL::PublicKey
BearSSLPrivateKey => BearSSL::PrivateKey
Print a warning when in debug mode when a BearSSL connection tries to
connect without having any defined authentication methods, since it will
fail.
Completely remove the empty axTLS compatibilty method
"::verify(char *fp, char *name)" because it can't be done w/BearSSL w/o
user code changes, and always failed. Better to have a compile failure
when we know at compile time the app won't do what is expected.
Completes the changes started by @d-a-v in PR #4833
Add a method allowing a user to send in a character string for the
fingerprint, like axTLS supported.
Implements part of PR #4833 from @d-a-v with changes requested in
discussion.
The BearSSL second stack, once allocated, was never deallocated. The
reference count of the stack pointer never hit 0 due to the initial
creation counting as one. Now, check to see if there is only one use_count
and if so then delete the stack.
SSL Sessions enable most of the SSL handshake to be skipped when both
client and server agree to use them. Add a BearSSLSession class and
an optional setting to the SSL client to enable this.
Note that SSL sessions are unrelated to HTTP sessions. They are
ephemeral and only relate to the SSL parameters, not anything at
the HTTP protocol level.
The cipher list count/pointer was cleared separately in the three
constructors available. Move this reset to _clear() to reduce code
duplication and keep the semantics.
Pull in latest BearSSL head (0.6 + minor additions) release and add AES_CCM
modes to the encryption options. Enable the aes_ccm initialization in client/server
The EC mul20 and square20 code was identical in two different files,
but because these copies were static, we ended up with an extra 6k of
duplicated code. Updated BearSSL to make them shared, saving 6KB.
The cipher list values were not initialized to NULL appropriately for the
BearSSL::WiFiClientSecure() constructor called by the Server object.
This caused a crash as a random value was free'd when conecting to the
SSL server object.
* Allow cipher specification for BearSSL
BearSSL has many more ciphers than axTLS, but they are more compute intensive
and slower. Add an option to use only the same, limited security, axTLS ciphers
as well as allow users to specify any suite of ciphers they want using standard
BearSSL formats.
Fixes#5110
* Rename methods to avoid axtls references.
* Allow std::vector to set a list of allowed ciphers
For C++ afficionados, allow std::vectors to be passed in to the setCipher()
routine.
The BearSSL object will now keep a copy of any set ciphers and free on object
destruction. These custom lists should normally only be 1-4 entries long, so it
is not expected to be a memory hog having this extra copy.
As part of the "clear connection configuration for reused objects"
patch, a ::stop would reset the self-signed, trust anchors, etc.
WiFiClient, unfortunately, calls ::stop as part of the connection
process, so all of these settings were lost.
Now only clear the connection settings on ::stop if we've already
been connected.
Also update the github public key which changed yet again.
Fixes#5086
Fixes#4882 and updates GitHub certificate fingerprint to the current one
in BearSSL_Validation example.
When setting a authentication mode or stopping, clear all others out in case
the object is being re-used.
Add in a yield during the SSL handshake to allow a graceful timeout and not
a WDT error when the remote server hiccups. Thanks to @Jeroen88 for
finding and testing this.
When a message is sent by the app that is larger than the SSL buffer,
it will take multiple TLS fragments to transfer. Writes will loop
through and not return until either all data is transferred or there
is an error.
When the TCP socket is closed there may be some data left in the
BearSSL internal buffers which can be read by the application.
The BearSSL pump, however, would always return no data available
in the case the socket was disconnected before checking if the
SSL was in a state where the app could possibly read.
Fix by returning if the state is available, even if the connection
is gone. Eventually no more data will become available to read
and the original -1 will be returned.
This should match the existing axTLS ::connected() behavior.
The SSL pipeline is multi-stage, and the TCP connection can go down
even though there is still data waiting to be decrypted or in the
decryption buffer.
Explicitly check that there if there can be any data made available
to the app, and if so report that we are still connected(). When
there is no data and there is no TCP connection, report disconnected.
BearSSL (https://www.bearssl.org) is a TLS(SSL) library written by
Thomas Pornin that is optimized for lower-memory embedded systems
like the ESP8266. It supports a wide variety of modern ciphers and
is unique in that it doesn't perform any memory allocations during
operation (which is the unfortunate bane of the current axTLS).
BearSSL is also absolutely focused on security and by default performs
all its security checks on x.509 certificates during the connection
phase (but if you want to be insecure and dangerous, that's possible
too).
While it does support unidirectional SSL buffers, like axTLS,
as implemented the ESP8266 wrappers only support bidirectional
buffers. These bidirectional buffers avoid deadlocks in protocols
which don't have well separated receive and transmit periods.
This patch adds several classes which allow connecting to TLS servers
using this library in almost the same way as axTLS:
BearSSL::WiFiClientSecure - WiFiClient that supports TLS
BearSSL::WiFiServerSecure - WiFiServer supporting TLS and client certs
It also introduces objects for PEM/DER encoded keys and certificates:
BearSSLX509List - x.509 Certificate (list) for general use
BearSSLPrivateKey - RSA or EC private key
BearSSLPublicKey - RSA or EC public key (i.e. from a public website)
Finally, it adds a Certificate Authority store object which lets
BearSSL access a set of trusted CA certificates on SPIFFS to allow it
to verify the identity of any remote site on the Internet, without
requiring RAM except for the single matching certificate.
CertStoreSPIFFSBearSSL - Certificate store utility
Client certificates are supported for the BearSSL::WiFiClientSecure, and
what's more the BearSSL::WiFiServerSecure can also *require* remote clients
to have a trusted certificate signed by a specific CA (or yourself with
self-signing CAs).
Maximum Fragment Length Negotiation probing and usage are supported, but
be aware that most sites on the Internet don't support it yet. When
available, you can reduce the memory footprint of the SSL client or server
dramatically (i.e. down to 2-8KB vs. the ~22KB required for a full 16K
receive fragment and 512b send fragment). You can also manually set a
smaller fragment size and guarantee at your protocol level all data will
fit within it.
Examples are included to show the usage of these new features.
axTLS has been moved to its own namespace, "axtls". A default "using"
clause allows existing apps to run using axTLS without any changes.
The BearSSL::WiFi{client,server}Secure implements the axTLS
client/server API which lets many end user applications take advantage
of BearSSL with few or no changes.
The BearSSL static library used presently is stored at
https://github.com/earlephilhower/bearssl-esp8266 and can be built
using the standard ESP8266 toolchain.
