This patch modifies the internal md context structure in md_wrap.c to
add return values to the function pointers. This enables us to use the
new API in the corresponding MD modules so that failures can be
found at any point in an MD computation.
The following function calls are being deprecated to introduce int
return values.
* mbedtls_sha512()
* mbedtls_sha512_starts()
* mbedtls_sha512_update()
* mbedtls_sha512_finish()
* mbedtls_sha512_process()
The return codes can be used to return error values. This is important
when using hardware accelerators.
The following function calls are being deprecated to introduce int
return values.
* mbedtls_sha256()
* mbedtls_sha256_starts()
* mbedtls_sha256_update()
* mbedtls_sha256_finish()
* mbedtls_sha256_process()
The return codes can be used to return error values. This is important
when using hardware accelerators.
The following function calls are being deprecated to introduce int
return values.
* mbedtls_ripemd160()
* mbedtls_ripemd160_starts()
* mbedtls_ripemd160_update()
* mbedtls_ripemd160_finish()
* mbedtls_ripemd160_process()
The return codes can be used to return error values. This is important
when using hardware accelerators.
The following function calls are being deprecated to introduce int
return values.
* mbedtls_md5()
* mbedtls_md5_starts()
* mbedtls_md5_update()
* mbedtls_md5_finish()
* mbedtls_md5_process()
The return codes can be used to return error values. This is important
when using hardware accelerators.
The following function calls are being deprecated to introduce int
return values.
* mbedtls_md4()
* mbedtls_md4_starts()
* mbedtls_md4_update()
* mbedtls_md4_finish()
* mbedtls_md4_process()
The return codes can be used to return error values. This is important
when using hardware accelerators.
The following function calls are being deprecated to introduce int
return values.
* mbedtls_md2()
* mbedtls_md2_starts()
* mbedtls_md2_update()
* mbedtls_md2_finish()
* mbedtls_md2_process()
The return codes can be used to return error values. This is important
when using hardware accelerators.
The following function calls are being deprecated to introduce int
return values.
* mbedtls_sha1()
* mbedtls_sha1_starts()
* mbedtls_sha1_update()
* mbedtls_sha1_finish()
* mbedtls_sha1_process()
The return codes can be used to return error values. This is important
when using hardware accelerators.
The check `if( *p + n > end )` in `ssl_parse_client_psk_identity` is
unsafe because `*p + n` might overflow, thus bypassing the check. As
`n` is a user-specified value up to 65K, this is relevant if the
library happens to be located in the last 65K of virtual memory.
This commit replaces the check by a safe version.
This patch modifies the function mbedtls_gcm_self_test() function to
ensure that AES-GCM-192 tests are only run if the key size is supported
by the available implementation. This is useful when using
MBEDTLS_AES_ALT as some hardware crypto accelerators might not support
AES-192.
This patch modifies the function mbedtls_aes_selftest() function to
ensure that AES-192 tests are only run if the key size is supported by
the available implementation. This is useful when using MBEDTLS_AES_ALT
as some hardware crypto accelerators might not support AES-192.
* restricted/iotssl-1398:
Add ChangeLog entry
Ensure application data records are not kept when fully processed
Add hard assertion to mbedtls_ssl_read_record_layer
Fix mbedtls_ssl_read
Simplify retaining of messages for future processing
This commit fixes the following case: If a client is both expecting a
SERVER_HELLO and has an application data record that's partially
processed in flight (that's the situation the client gets into after
receiving a ServerHelloRequest followed by ApplicationData), a
subsequent call to mbedtls_ssl_read will set keep_current_message = 1
when seeing the unexpected application data, but not reset it to 0
after the application data has been processed. This commit fixes this.
It also documents and suggests how the problem might be solved in a
more structural way on the long run.
This commit adds a hard assertion to mbedtls_ssl_read_record_layer
triggering if both ssl->in_hslen and ssl->in_offt are not 0. This
should never happen, and if it does, there's no sensible way of
telling whether the previous message was a handshake or an application
data message.
There are situations in which it is not clear what message to expect
next. For example, the message following the ServerHello might be
either a Certificate, a ServerKeyExchange or a CertificateRequest. We
deal with this situation in the following way: Initially, the message
processing function for one of the allowed message types is called,
which fetches and decodes a new message. If that message is not the
expected one, the function returns successfully (instead of throwing
an error as usual for unexpected messages), and the handshake
continues to the processing function for the next possible message. To
not have this function fetch a new message, a flag in the SSL context
structure is used to indicate that the last message was retained for
further processing, and if that's set, the following processing
function will not fetch a new record.
This commit simplifies the usage of this message-retaining parameter
by doing the check within the record-fetching routine instead of the
specific message-processing routines. The code gets cleaner this way
and allows retaining messages to be used in other situations as well
without much effort. This will be used in the next commits.
This commit adds four tests to tests/ssl-opt.sh:
(1) & (2): Check behaviour of optional/required verification when the
trusted CA chain is empty.
(3) & (4): Check behaviour of optional/required verification when the
client receives a server certificate with an unsupported curve.
This commit changes the behaviour of mbedtls_ssl_parse_certificate
to make the two authentication modes MBEDTLS_SSL_VERIFY_REQUIRED and
MBEDTLS_SSL_VERIFY_OPTIONAL be in the following relationship:
Mode == MBEDTLS_SSL_VERIFY_REQUIRED
<=> Mode == MBEDTLS_SSL_VERIFY_OPTIONAL + check verify result
Also, it changes the behaviour to perform the certificate chain
verification even if the trusted CA chain is empty. Previously, the
function failed in this case, even when using optional verification,
which was brought up in #864.
* gilles/IOTSSL-1330/development:
Changelog entry for the bug fixes
SSLv3: when refusing renegotiation, stop processing
Ignore failures when sending fatal alerts
Cleaned up double variable declaration
Code portability fix
Added changelog entry
Send TLS alerts in many more cases
Skip all non-executables in run-test-suites.pl
SSL tests: server requires auth, client has no certificate
Balanced braces across preprocessor conditionals
Support setting the ports on the command line
By default, keep allowing SHA-1 in key exchange signatures. Disabling
it causes compatibility issues, especially with clients that use
TLS1.2 but don't send the signature_algorithms extension.
SHA-1 is forbidden in certificates by default, since it's vulnerable
to offline collision-based attacks.
In the TLS test client, allow SHA-1 as a signature hash algorithm.
Without this, the renegotation tests failed.
A previous commit had allowed SHA-1 via the certificate profile but
that only applied before the initial negotiation which includes the
signature_algorithms extension.
Default to forbidding the use of SHA-1 in TLS where it is unsafe: for
certificate signing, and as the signature hash algorithm for the TLS
1.2 handshake signature. SHA-1 remains allowed in HMAC-SHA-1 in the
XXX_SHA ciphersuites and in the PRF for TLS <= 1.1.
For easy backward compatibility for use in controlled environments,
turn on the MBEDTLS_TLS_DEFAULT_ALLOW_SHA1 compiled-time option.
* hanno/sig_hash_compatibility:
Improve documentation
Split long lines
Remember suitable hash function for any signature algorithm.
Introduce macros and functions to characterize certain ciphersuites.
Add missing return code checks in the functions pem_des_decrypt(),
pem_3des_decrypt() and pem_aes_decrypt() so that the calling function
mbedtls_pem_read_buffer() is notified of errors reported by the crypto
primitives AES, DES and 3DES.
Fixed a bug in ssl_srv.c when parsing TLS_FALLBACK_SCSV in the
ciphersuite list that caused it to miss it sometimes. Reported by Hugo
Leisink as issue #810. Fix initially by @andreasag01; this commit
isolates the bug fix and adds a non-regression test.
This patch modifies the following 2 functions in the AES module to
change the return type from void to int:
* mbedtls_aes_encrypt() -> mbedtls_internal_aes_encrypt()
* mbedtls_aes_decrypt() -> mbedtls_internal_aes_decrypt()
This change is necessary to allow users of MBEDTLS_AES_ALT,
MBEDTLS_AES_DECRYPT_ALT and MBEDTLS_AES_ENCRYPT_ALT to return an error
code when replacing the default with their own implementation, e.g.
a hardware crypto accelerator.
The RSA private key functions rsa_rsaes_pkcs1_v15_decrypt and
rsa_rsaes_oaep_decrypt put sensitive data (decryption results) on the
stack. Wipe it before returning.
Thanks to Laurent Simon for reporting this issue.
The sliding window exponentiation algorithm is vulnerable to
side-channel attacks. As a countermeasure we add exponent blinding in
order to prevent combining the results of different measurements.
This commit handles the case when the Chinese Remainder Theorem is used
to accelerate the computation.
The sliding window exponentiation algorithm is vulnerable to
side-channel attacks. As a countermeasure we add exponent blinding in
order to prevent combining the results of fifferent measurements.
This commits handles the case when the Chinese Remainder Theorem is NOT
used to accelerate computations.
According to RFC5246 the server can indicate the known Certificate
Authorities or can constrain the aurhorisation space by sending a
certificate list. This part of the message is optional and if omitted,
the client may send any certificate in the response.
The previous behaviour of mbed TLS was to always send the name of all the
CAs that are configured as root CAs. In certain cases this might cause
usability and privacy issues for example:
- If the list of the CA names is longer than the peers input buffer then
the handshake will fail
- If the configured CAs belong to third parties, this message gives away
information on the relations to these third parties
Therefore we introduce an option to suppress the CA list in the
Certificate Request message.
Providing this feature as a runtime option comes with a little cost in
code size and advantages in maintenance and flexibility.
This commit changes `ssl_parse_signature_algorithms_ext` to remember
one suitable ( := supported by client and by our config ) hash
algorithm per signature algorithm.
It also modifies the ciphersuite checking function
`ssl_ciphersuite_match` to refuse a suite if there
is no suitable hash algorithm.
Finally, it adds the corresponding entry to the ChangeLog.
The routine `mbedtls_ssl_write_server_key_exchange` heavily depends on
what kind of cipher suite is active: some don't need a
ServerKeyExchange at all, some need (EC)DH parameters but no server
signature, some require both. Each time we want to restrict a certain
piece of code to some class of ciphersuites, it is guarded by a
lengthy concatentation of configuration checks determining whether at
least one of the relevant cipher suites is enabled in the config; on
the code level, it is guarded by the check whether one of these
cipher suites is the active one.
To ease readability of the code, this commit introduces several helper
macros and helper functions that can be used to determine whether a
certain class of ciphersuites (a) is active in the config, and
(b) contains the currently present ciphersuite.
With this commit the Elliptic Curve Point interface is rewised. Two
compile time options has been removed to simplify the interface and
the function names got a new prefix that indicates that these functions
are for internal use and not part of the public interface.
The intended use of the abstraction layer for Elliptic Curve Point
arithmetic is to enable using hardware cryptographic accelerators.
These devices are a shared resource and the driver code rarely provides
thread safety.
This commit adds mutexes to the abstraction layer to protect the device
in a multi-threaded environment.
The primary use case behind providing an abstraction layer to enable
alternative Elliptic Curve Point arithmetic implementation, is making
use of cryptographic acceleration hardware if it is present.
To provide thread safety for the hardware accelerator we need a mutex
to guard it.
The compile time macros enabling the initialisation and deinitialisation
in the alternative Elliptic Curve Point arithmetic implementation had
names that did not end with '_ALT' as required by check-names.sh.
This patch introduces some additional checks in the PK module for 64-bit
systems only. The problem is that the API functions in the PK
abstraction accept a size_t value for the hashlen, while the RSA module
accepts an unsigned int for the hashlen. Instead of silently casting
size_t to unsigned int, this change checks whether the hashlen overflows
an unsigned int and returns an error.
The test case was generated by modifying our signature code so that it
produces a 7-byte long padding (which also means garbage at the end, so it is
essential in to check that the error that is detected first is indeed the
padding rather than the final length check).
In many places in TLS handling, some code detects a fatal error, sends
a fatal alert message, and returns to the caller. If sending the alert
fails, then return the error that triggered the alert, rather than
overriding the return status. This effectively causes alert sending
failures to be ignored. Formerly the code was inconsistently sometimes
doing one, sometimes the other.
In general ignoring the alert is the right thing: what matters to the
caller is the original error. A typical alert failure is that the
connection is already closed.
One case which remains not handled correctly is if the alert remains
in the output buffer (WANT_WRITE). Then it won't be sent, or will be
truncated. We'd need to either delay the application error or record
the write buffering notice; to be done later.
When provided with an empty line, mpi_read_file causes a numeric
underflow resulting in a stack underflow. This commit fixes this and
adds some documentation to mpi_read_file.
The modular inversion function hangs when provided with the modulus 1. This commit refuses this modulus with a BAD_INPUT error code. It also adds a test for this case.
The TLS client and server code was usually closing the connection in
case of a fatal error without sending an alert. This commit adds
alerts in many cases.
Added one test case to detect that we send the alert, where a server
complains that the client's certificate is from an unknown CA (case
tracked internally as IOTSSL-1330).
Fix a buffer overflow when writting a string representation of an MPI
number to a buffer in hexadecimal. The problem occurs because hex
digits are written in pairs and this is not accounted for in the
calculation of the required buffer size when the number of digits is
odd.
When using ssl_cookie with MBEDTLS_THREADING_C, fix a resource leak caused by
initiating a mutex in mbedtls_ssl_cookie_free instead of freeing it.
Raised and fix suggested by lan Gillingham in the mbed TLS forum
Tracked in #771
The function ecp_mod_koblitz computed the space for the result of a
multiplication optimally for that specific case, but unfortunately
the function mbedtls_mpi_mul_mpi performs a generic, suboptimal
calculation and needs one more limb for the result. Since the result's
buffer is on the stack, the best case scenario is that the program
stops.
This only happened on 64 bit platforms.
Fixes#569
A heap overread might happen when parsing malformed certificates.
Reported by Peng Li and Yueh-Hsun Lin.
Refactoring the parsing fixes the problem. This commit applies the
relevant part of the OpenVPN contribution applied to mbed TLS 1.3
in commit 17da9dd829.
Fixes a regression introduced by an earlier commit that modified
x509_crt_verify_top() to ensure that valid certificates that are after past or
future valid in the chain are processed. However the change introduced a change
in behaviour that caused the verification flags MBEDTLS_X509_BADCERT_EXPIRED and
MBEDTLS_BADCERT_FUTURE to always be set whenever there is a failure in the
verification regardless of the cause.
The fix maintains both behaviours:
* Ensure that valid certificates after future and past are verified
* Ensure that the correct verification flags are set.
Modifies the function mbedtls_x509_crl_parse() to ensure that a CRL in PEM
format with trailing characters after the footer does not result in the
execution of an infinite loop.
Fix potential integer overflows in the function mbedtls_base64_decode().
This overflow would mainly be exploitable in 32-bit systems and could
cause buffer bound checks to be bypassed.
Fix potential integer overflows in the following functions:
* mbedtls_md2_update() to be bypassed and cause
* mbedtls_cipher_update()
* mbedtls_ctr_drbg_reseed()
This overflows would mainly be exploitable in 32-bit systems and could
cause buffer bound checks to be bypassed.
Fix an incorrect condition in ssl_check_ctr_renegotiate() that compared
64 bits of record counter instead of 48 bits as described in RFC 6347
Section 4.3.1. This would cause the function's return value to be
occasionally incorrect and the renegotiation routines to be triggered
at unexpected times.
This PR fixes a number of unused variable/function compilation warnings
that arise when using a config.h that does not define the macro
MBEDTLS_PEM_PARSE_C.
Fixes many typos, and errors in comments.
* Clarifies many comments
* Grammar correction in config.pl help text
* Removed comment about MBEDTLS_X509_EXT_NS_CERT_TYPE.
* Comment typo fix (Dont => Don't)
* Comment typo fix (assure => ensure)
* Comment typo fix (byes => bytes)
* Added citation for quoted standard
* Comment typo fix (one complement => 1's complement)
The is some debate about whether to prefer "one's complement", "ones'
complement", or "1's complement". The more recent RFCs related to TLS
(RFC 6347, RFC 4347, etc) use " 1's complement", so I followed that
convention.
* Added missing ")" in comment
* Comment alignment
* Incorrect comment after #endif
This change fixes a regression introduced by an earlier commit that
modified x509_crt_verify_top() to ensure that valid certificates
that are after past or future valid in the chain are processed. However
the change introduced a change in behaviour that caused the
verification flags MBEDTLS_X509_BADCERT_EXPIRED and
MBEDTLS_BADCERT_FUTURE to always be set whenever there is a failure in
the verification regardless of the cause.
The fix maintains both behaviours:
* Ensure that valid certificates after future and past are verified
* Ensure that the correct verification flags are set.
To do so, a temporary pointer to the first future or past valid
certificate is maintained while traversing the chain. If a truly valid
certificate is found then that one is used, otherwise if no valid
certificate is found and the end of the chain is reached, the program
reverts back to using the future or past valid certificate.
This patch modifies the function mbedtls_x509_crl_parse() to ensure
that a CRL in PEM format with trailing characters after the footer does
not result in the execution of an infinite loop.
Fixes many typos, and errors in comments.
* Clarifies many comments
* Grammar correction in config.pl help text
* Removed comment about MBEDTLS_X509_EXT_NS_CERT_TYPE.
* Comment typo fix (Dont => Don't)
* Comment typo fix (assure => ensure)
* Comment typo fix (byes => bytes)
* Added citation for quoted standard
* Comment typo fix (one complement => 1's complement)
The is some debate about whether to prefer "one's complement", "ones'
complement", or "1's complement". The more recent RFCs related to TLS
(RFC 6347, RFC 4347, etc) use " 1's complement", so I followed that
convention.
* Added missing ")" in comment
* Comment alignment
* Incorrect comment after #endif
The PKCS#1 standard says nothing about the relation between P and Q
but many libraries guarantee P>Q and mbed TLS did so too in earlier
versions.
This commit restores this behaviour.
Fix implementation and documentation missmatch for the function
arguments to mbedtls_gcm_finish(). Also, removed redundant if condition
that always evaluates to true.
The bracketing in some expressions where an assignment was being made in an if statement in cmac.c had been accidentally broken and was causing compiler warnings with armcc.
Minor fixes following review including:
* formatting changes including indentation and code style
* corrections
* removal of debug code
* clarification of code through variable renaming
* memory leak
* compiler warnings
Change the CMAC interface to match the mbedtls_md_hmac_xxxx() interface. This
changes the overall design of the CMAC interface to make it more consistent with
the existing HMAC interface, and will allow incremental updates of input data
rather than requiring all data to be presented at once, which is what the
current interface requires.
- use one less temporary buffer
- pedantic: in_len + 15 was a potential overflow
- use a more explicit name instead of 'flag'
- Mn was a bit misleading
The previous version had secret-dependent memory accesses. While it was
probably not an issue in practice cause the two bytes of the array are
probably on the same cache line anyway, as a matter of principle this should
be avoided.
Due to inconsistent freeing strategy in pkparse.c the sample mutex
implementation in threading.c could lead to undefined behaviour by
destroying the same mutex several times.
This fix prevents mutexes from being destroyed several times in the
sample threading implementation.
The library/net.c and its corresponding include/mbedtls/net.h file are
renamed to library/net_sockets.c and include/mbedtls/net_sockets.h
respectively. This is to avoid naming collisions in projects which also
have files with the common name 'net'.
The PKCS#1 standard says nothing about the relation between P and Q
but many libraries guarantee P>Q and mbed TLS did so too in earlier
versions.
This commit restores this behaviour.
Fix implementation and documentation missmatch for the function
arguments to mbedtls_gcm_finish(). Also, removed redundant if condition
that always evaluates to true.
Certificates with unsupported algorithms in the certificate chain
prevented verification even if a certificate before the unsupported
ones was already trusted.
We change the behaviour to ignoring every certificate with unknown
(unsupported) signature algorithm oid when parsing the certificate
chain received from the peer.
The bracketing in some expressions where an assignment was being made in an if statement in cmac.c had been accidentally broken and was causing compiler warnings with armcc.
Minor fixes following review including:
* formatting changes including indentation and code style
* corrections
* removal of debug code
* clarification of code through variable renaming
* memory leak
* compiler warnings
Change the CMAC interface to match the mbedtls_md_hmac_xxxx() interface. This
changes the overall design of the CMAC interface to make it more consistent with
the existing HMAC interface, and will allow incremental updates of input data
rather than requiring all data to be presented at once, which is what the
current interface requires.
- use one less temporary buffer
- pedantic: in_len + 15 was a potential overflow
- use a more explicit name instead of 'flag'
- Mn was a bit misleading
The previous version had secret-dependent memory accesses. While it was
probably not an issue in practice cause the two bytes of the array are
probably on the same cache line anyway, as a matter of principle this should
be avoided.
Due to inconsistent freeing strategy in pkparse.c the sample mutex
implementation in threading.c could lead to undefined behaviour by
destroying the same mutex several times.
This fix prevents mutexes from being destroyed several times in the
sample threading implementation.
The library/net.c and its corresponding include/mbedtls/net.h file are
renamed to library/net_sockets.c and include/mbedtls/net_sockets.h
respectively. This is to avoid naming collisions in projects which also
have files with the common name 'net'.
Allow the size of the entry_name character array in x509_crt.c to be
configurable through a macro in config.h. entry_name holds a
path/filename string. The macro introduced in
MBEDTLS_X509_MAX_FILE_PATH_LEN.
Ensure that the entropy self test always fails whenever
MBEDTLS_TEST_NULL_ENTROPY is defined. This is because the option is
meant to be for testing and development purposes rather than production
quality software. Also, this patch enhances the documentation for
mbedtls_entropy_source_self_test() and mbedtls_entropy_self_test().
Instead of polling the hardware entropy source a single time and
comparing the output with itself, the source is polled at least twice
and make sure that the separate outputs are different.
The self test is a quick way to check at startup whether the entropy
sources are functioning correctly. The self test only polls 8 bytes
from the default entropy source and performs the following checks:
- The bytes are not all 0x00 or 0xFF.
- The hardware does not return an error when polled.
- The entropy does not provide data in a patter. Only check pattern
at byte, word and long word sizes.
In platform.c, made the time functions dependent on the configuration
MBEDTLS_HAVE_TIME to fix a build break where the functions could be
built but the mbedtls_time_t was not defined.
Separates platform time abstraction into it's own header from the
general platform abstraction as both depend on different build options.
(MBEDTLS_PLATFORM_C vs MBEDTLS_HAVE_TIME)
This commit fixes following warning:
> CC: aes.c
> aes.c: In function 'mbedtls_aes_self_test':
> aes.c:1225:19: error: unused variable 'iv' [-Werror=unused-variable]
> unsigned char iv[16];
> ^
> cc1: all warnings being treated as errors
If the option MBEDTLS_TEST_NULL_ENTROPY is enabled, the cmake generated
makefile will generate an error unless a UNSAFE_BUILD switch is also enabled.
Equally, a similar warning will always be generated if the Makefile is built,
and another warning is generated on every compilation of entropy.c.
This is to ensure the user is aware of what they're doing when they enable the
null entropy option.
Update the NV entropy seed before generating any entropy for outside
use. The reason this is triggered here and not in mbedtls_entropy_init(),
is that not all entropy sources mights have been added at that time.
Introduces mbedtls_nv_seed_read() and mbedtls_nv_seed_write().
The platform-layer functions are only available when
MBEDTLS_ENTROPY_NV_SEED is enabled.
Add a switch that turns entropy collecting off entirely, but enables
mbed TLS to run in an entirely unsafe mode. Enables to test mbed TLS
on platforms that don't have their entropy sources integrated yet.
Commit daf534d from PR #457 breaks the build. This may reintroduce a
clang-analyse warning, but this is the wrong fix for that.
The fix removed a call to mbedtls_ecp_curve_info_from_grp_id() to find
the curve info. This fix adds that back in.
The check is already effectively performed later in the function, but
implicitly, so Clang's analysis fail to notice the functions are in
fact safe. Pulling the check up to the top helps Clang to verify the
behaviour.
Since the buffer is used in a few places, it seems Clang isn't clever
enough to realise that the first byte is never touched. So, even though
the function has a correct null check for ssl->handshake, Clang
complains. Pulling the handshake type out into its own variable is
enough for Clang's analysis to kick in though.
The function appears to be safe, since grow() is called with sensible
arguments in previous functions. Ideally Clang would be clever enough to
realise this. Even if N has size MBEDTLS_MPI_MAX_LIMBS, which will
cause the grow to fail, the affected lines in montmul won't be reached.
Having this sanity check can hardly hurt though.
It is used only by `mbedtls_sha512_process()`, and in case `MBEDTLS_SHA512_PROCESS_ALT` is defined, it still cannot be reused because of `static` declaration.
On x32 systems, pointers are 4-bytes wide and are therefore stored in %e?x
registers (instead of %r?x registers). These registers must be accessed using
"addl" instead of "addq", however the GNU assembler will acccept the generic
"add" instruction and determine the correct opcode based on the registers
passed to it.
The server code parses the client hello extensions even when the
protocol is SSLv3 and this behaviour is non compliant with rfc6101.
Also the server sends extensions in the server hello and omitting
them may prevent interoperability problems.
Commit daf534d from PR #457 breaks the build. This may reintroduce a
clang-analyse warning, but this is the wrong fix for that.
The fix removed a call to mbedtls_ecp_curve_info_from_grp_id() to find
the curve info. This fix adds that back in.
The check is already effectively performed later in the function, but
implicitly, so Clang's analysis fail to notice the functions are in
fact safe. Pulling the check up to the top helps Clang to verify the
behaviour.
Since the buffer is used in a few places, it seems Clang isn't clever
enough to realise that the first byte is never touched. So, even though
the function has a correct null check for ssl->handshake, Clang
complains. Pulling the handshake type out into its own variable is
enough for Clang's analysis to kick in though.
The function appears to be safe, since grow() is called with sensible
arguments in previous functions. Ideally Clang would be clever enough to
realise this. Even if N has size MBEDTLS_MPI_MAX_LIMBS, which will
cause the grow to fail, the affected lines in montmul won't be reached.
Having this sanity check can hardly hurt though.
Fix an issue that caused valid certificates being rejected whenever an
expired or not yet valid version of the trusted certificate was before the
valid version in the trusted certificate list.
The callback typedefs defined for mbedtls_ssl_set_bio() and
mbedtls_ssl_set_timer_cb() were not used consistently where the callbacks were
referenced in structures or in code.
- basicContraints checks are done during verification
- there is no need to set extensions that are not present to default values,
as the code using the extension will check if it was present using
ext_types. (And default values would not make sense anyway.)
- document why we made that choice
- remove the two TODOs about checking hash and CA
- remove the code that parsed certificate_type: it did nothing except store
the selected type in handshake->cert_type, but that field was never accessed
afterwards. Since handshake_params is now an internal type, we can remove that
field without breaking the ABI.
We don't implement anonymous key exchanges, and we don't intend to, so it can
never happen that an unauthenticated server requests a certificate from us.
After the record contents are decompressed, in_len is no longer
accessed directly, only in_msglen is accessed. in_len is only read by
ssl_parse_record_header() which happens before ssl_prepare_record_contents().
This is also made clear by the fact that in_len is not touched after
decrypting anyway, so if it was accessed after that it would be wrong unless
decryption is used - as this is not the case, it show in_len is not accessed.
Previously it was failing with errors about headers not found, which is
suboptimal in terms of clarity. Now give a clean error with pointer to the
documentation.
Do the checks in the .c files rather than check_config.h as it keeps them
closer to the platform-specific implementations.
