Commit Graph

319 Commits

Author SHA1 Message Date
Ron Eldor
df48efa77a Skip uncritical unsupported extensions
Skip extensions that have support in the `oid` layer`, but
no parser found in the x509 layer, in case these are not critical.
2019-04-10 11:06:53 +03:00
Jarno Lamsa
2ee67a66f4 Remove mbedtls_ from the static function name 2019-04-01 14:59:33 +03:00
Jarno Lamsa
31d9db6195 Change the verify function naming
Change the naming to reflect that the function uses a new ca callback
feature to distinguish different callbacks.
2019-04-01 14:33:49 +03:00
Hanno Becker
f53893b00c Implement X.509 CRT verification using CA callback 2019-03-28 16:13:44 +00:00
Hanno Becker
3116fb362c Add prototype for CRT verification with static and dynamic CA list
So far, there were the following CRT verification functions:
- `mbedtls_x509_crt_verify()` -- no profile, no restartable ECC
- `mbedtls_x509_crt_verify_with_profile()` -- profile, no restartable ECC
- `mbedtls_x509_crt_verify_restartable()` -- profile, restartable ECC
all publicly declared and offering increasing functionality.

On the implementation-side,
- `mbedtls_x509_crt_verify()` resolves to
  a call to `mbedtls_x509_crt_verify_with_profile()` setting
  the profile to `NULL`, and
- `mbedtls_x509_crt_verify_with_profile()`
  resolves to a call to ``mbedtls_x509_crt_verify_restartable()`
  setting the ECC restart context to NULL.

This commit adds two more functions to this zoo:
- `mbedtls_x509_crt_verify_with_cb()`
- `x509_crt_verify_restartable_cb()`

Here, `mbedtls_x509_crt_verify_with_cb()` is similar to
`mbedtls_x509_crt_verify_with_profile()` but uses a CA callback
instead of a static CA list, and no restart context.

`x509_crt_verify_restartable_cb()` is similar to
`mbedtls_x509_crt_verify_restartable()` but allows to either use
a static list of trusted CAs _or_ a trusted CA callback.

On the implementation-side,
- the body of `mbedtls_x509_crt_verify_restartable()` is moved to
  `x509_crt_verify_restartable_cb()`, and the new version of
  `mbedtls_x509_crt_verify_restartable()` just resolves to
  `x509_crt_verify_restartable_cb()` with the trusted CA callback
  set to NULL.
- The new function `mbedtls_x509_crt_verify_with_cb()`
  forward to `x509_crt_verify_restartable_cb()` with the restart
  context set to `NULL`.

There's no change to the implementation yet, and in particular,
`mbedtls_x509_crt_verify_with_cb()` isn't yet usable.
2019-03-28 16:13:43 +00:00
Hanno Becker
494dd7a6b4 Add raw public key buffer bounds to mbedtls_x509_crt struct
This commit adds an ASN.1 buffer field `pk_raw` to `mbedtls_x509_crt`
which stores the bounds of the raw public key data within an X.509 CRT.

This will be useful in subsequent commits to extract the peer's public
key from its certificate chain.
2019-02-26 14:38:09 +00:00
Jaeden Amero
461bd3dcca Merge remote-tracking branch 'origin/pr/2454' into development 2019-02-22 10:32:44 +00:00
Jaeden Amero
8963b0311c Merge remote-tracking branch 'origin/pr/2411' into development 2019-02-22 10:32:44 +00:00
Jaeden Amero
3497323f79 Initialize PSA Crypto operation contexts
It is now required to initialize PSA Crypto operation contexts before
calling psa_*_setup(). Otherwise, one gets a PSA_ERROR_BAD_STATE error.
2019-02-20 10:58:55 +00:00
Hanno Becker
1eeca41472 Improve macro hygiene
This commit improves hygiene and formatting of macro definitions
throughout the library. Specifically:
- It adds brackets around parameters to avoid unintended
  interpretation of arguments, e.g. due to operator precedence.
- It adds uses of the `do { ... } while( 0 )` idiom for macros that
  can be used as commands.
2019-02-19 17:59:00 +00:00
Hanno Becker
1a65dcd44f Add a new X.509 API call for copy-less parsing of CRTs
Context:
The existing API `mbedtls_x509_parse_crt_der()` for parsing DER
encoded X.509 CRTs unconditionally makes creates a copy of the
input buffer in RAM. While this comes at the benefit of easy use,
-- specifically: allowing the user to free or re-use the input
buffer right after the call -- it creates a significant memory
overhead, as the CRT is duplicated in memory (at least temporarily).
This might not be tolerable a resource constrained device.

As a remedy, this commit adds a new X.509 API call

   `mbedtls_x509_parse_crt_der_nocopy()`

which has the same signature as `mbedtls_x509_parse_crt_der()`
and almost the same semantics, with one difference: The input
buffer must persist and be unmodified for the lifetime of the
established instance of `mbedtls_x509_crt`, that is, until
`mbedtls_x509_crt_free()` is called.
2019-02-08 14:24:58 +00:00
Andrzej Kurek
de5a007316 Merge development commit f352f7 into development-psa 2019-02-01 07:03:03 -05:00
Andrzej Kurek
c470b6b021 Merge development commit 8e76332 into development-psa
Additional changes to temporarily enable running tests:
ssl_srv.c and test_suite_ecdh use mbedtls_ecp_group_load instead of
mbedtls_ecdh_setup
test_suite_ctr_drbg uses mbedtls_ctr_drbg_update instead of 
mbedtls_ctr_drbg_update_ret
2019-01-31 08:20:20 -05:00
Jaeden Amero
14eca249f1 Merge remote-tracking branch 'origin/pr/2213' into development 2019-01-30 15:01:20 +00:00
Antonin Décimo
36e89b5b71 Fix #2370, minor typos and spelling mistakes 2019-01-24 10:37:40 +01:00
Hanno Becker
a9375b35c0 Avoid MSVC compiler warning
MSVC warns about use of unary `-` operator on unsigned integers.
2019-01-10 09:21:24 +00:00
Hanno Becker
783f9c3514 Fix signed-to-unsigned integer conversion warning in X.509 module
Fixes #2212.
2019-01-10 09:21:24 +00:00
Jaeden Amero
5b46fe774b Merge remote-tracking branch 'upstream-public/pr/2157' into development 2018-12-06 16:06:57 +00:00
Andrzej Kurek
8b38ff57ab Remove trailing whitespace 2018-11-22 11:53:04 -05:00
Andrzej Kurek
a609337ca0 x509: remove unnecessary calls to psa_hash_abort
According to the documentation, it does not need to be called after a failed
psa_hash call.
2018-11-22 11:53:04 -05:00
Andrzej Kurek
d4a6553191 x509: use the PSA API to perform hashing operations
So far limited only to certificate verification withour CRL and CSR generation.
2018-11-22 11:53:04 -05:00
Simon Butcher
d83448b736 Merge remote-tracking branch 'public/pr/2052' into development-restricted-proposed 2018-11-07 12:59:14 +00:00
Hanno Becker
b75ffb5061 Don't perform binary comparison of CRL issuer and CA subject
Previously, when checking whether a CRT was revoked through
one of the configured CRLs, the library would only consider
those CRLs whose `issuer` field binary-matches the `subject`
field of the CA that has issued the CRT in question. If those
fields were not binary equivalent, the corresponding CRL was
discarded.

This is not in line with RFC 5280, which demands that the
comparison should be format- and case-insensitive. For example:

- If the same string is once encoded as a `PrintableString` and
  another time as a `UTF8String`, they should compare equal.
- If two strings differ only in their choice of upper and lower case
  letters, they should compare equal.

This commit fixes this by using the dedicated x509_name_cmp()
function to compare the CRL issuer with the CA subject.

Fixes #1784.
2018-11-05 11:54:06 +00:00
Hanno Becker
1f8527f1cf Move static x509_name_cmp() in library/x509_crt.c
A subsequent change will need this function earlier
within the file.
2018-11-05 11:54:06 +00:00
Krzysztof Stachowiak
c388a8c394 Fix typo in a test condition code 2018-10-31 16:49:20 +01:00
Manuel Pégourié-Gonnard
a5a3e40c4e Fix missing dereference.
Went unnoticed because it was only on a defensive code path, in an internal
function, so not exercised.
2018-10-16 11:27:23 +02:00
Manuel Pégourié-Gonnard
ee68cff813 Fix or improve some comments (and whitespace) 2018-10-15 15:27:49 +02:00
Simon Butcher
d2642584cb Make inclusion of stdio.h conditional in x509_crt.c
stdio.h was being included both conditionally if MBEDTLS_FS_IO was
defined, and also unconditionally, which made at least one of them
redundant.

This change removes the unconditional inclusion of stdio.h and makes it
conditional on MBEDTLS_PLATFORM_C.
2018-10-03 15:11:19 +01:00
Manuel Pégourié-Gonnard
125af948c3 Merge branch 'development-restricted' into iotssl-1260-non-blocking-ecc-restricted
* development-restricted: (578 commits)
  Update library version number to 2.13.1
  Don't define _POSIX_C_SOURCE in header file
  Don't declare and define gmtime()-mutex on Windows platforms
  Correct preprocessor guards determining use of gmtime()
  Correct documentation of mbedtls_platform_gmtime_r()
  Correct typo in documentation of mbedtls_platform_gmtime_r()
  Correct POSIX version check to determine presence of gmtime_r()
  Improve documentation of mbedtls_platform_gmtime_r()
  platform_utils.{c/h} -> platform_util.{c/h}
  Don't include platform_time.h if !MBEDTLS_HAVE_TIME
  Improve wording of documentation of MBEDTLS_PLATFORM_GMTIME_R_ALT
  Fix typo in documentation of MBEDTLS_PLATFORM_GMTIME_R_ALT
  Replace 'thread safe' by 'thread-safe' in the documentation
  Improve documentation of MBEDTLS_HAVE_TIME_DATE
  ChangeLog: Add missing renamings gmtime -> gmtime_r
  Improve documentation of MBEDTLS_HAVE_TIME_DATE
  Minor documentation improvements
  Style: Add missing period in documentation in threading.h
  Rename mbedtls_platform_gmtime() to mbedtls_platform_gmtime_r()
  Guard decl and use of gmtime mutex by HAVE_TIME_DATE and !GMTIME_ALT
  ...
2018-09-11 12:39:14 +02:00
Simon Butcher
129fa82908 Merge remote-tracking branch 'restricted/pr/470' into development-restricted 2018-08-28 15:26:11 +01:00
k-stachowiak
463928a74b Fix code formatting 2018-07-24 12:50:59 +02:00
Manuel Pégourié-Gonnard
78d7e8cbc7 Rename internal variable for consistency 2018-07-02 12:33:14 +02:00
k-stachowiak
dcae78a7a9 Make a buffer limit more specific 2018-06-28 16:32:54 +02:00
k-stachowiak
470dfbabb9 Simplify OID tag parsing in x509_get_cert_ext( ) 2018-06-28 16:23:39 +02:00
Manuel Pégourié-Gonnard
da19f4c79f Merge branch 'development' into iotssl-1260-non-blocking-ecc-restricted
Summary of merge conflicts:

include/mbedtls/ecdh.h -> documentation style
include/mbedtls/ecdsa.h -> documentation style
include/mbedtls/ecp.h -> alt style, new error codes, documentation style
include/mbedtls/error.h -> new error codes
library/error.c -> new error codes (generated anyway)
library/ecp.c:
    - code of an extracted function was changed
library/ssl_cli.c:
    - code addition on one side near code change on the other side
      (ciphersuite validation)
library/x509_crt.c -> various things
    - top fo file: helper structure added near old zeroize removed
    - documentation of find_parent_in()'s signature: improved on one side,
      added arguments on the other side
    - documentation of find_parent()'s signature: same as above
    - verify_chain(): variables initialised later to give compiler an
      opportunity to warn us if not initialised on a code path
    - find_parent(): funcion structure completely changed, for some reason git
      tried to insert a paragraph of the old structure...
    - merge_flags_with_cb(): data structure changed, one line was fixed with a
      cast to keep MSVC happy, this cast is already in the new version
    - in verify_restratable(): adjacent independent changes (function
      signature on one line, variable type on the next)
programs/ssl/ssl_client2.c:
    - testing for IN_PROGRESS return code near idle() (event-driven):
      don't wait for data in the the socket if ECP_IN_PROGRESS
tests/data_files/Makefile: adjacent independent additions
tests/suites/test_suite_ecdsa.data: adjacent independent additions
tests/suites/test_suite_x509parse.data: adjacent independent additions

* development: (1059 commits)
  Change symlink to hardlink to avoid permission issues
  Fix out-of-tree testing symlinks on Windows
  Updated version number to 2.10.0 for release
  Add a disabled CMAC define in the no-entropy configuration
  Adapt the ARIA test cases for new ECB function
  Fix file permissions for ssl.h
  Add ChangeLog entry for PR#1651
  Fix MicroBlaze register typo.
  Fix typo in doc and copy missing warning
  Fix edit mistake in cipher_wrap.c
  Update CTR doc for the 64-bit block cipher
  Update CTR doc for other 128-bit block ciphers
  Slightly tune ARIA CTR documentation
  Remove double declaration of mbedtls_ssl_list_ciphersuites
  Update CTR documentation
  Use zeroize function from new platform_util
  Move to new header style for ALT implementations
  Add ifdef for selftest in header file
  Fix typo in comments
  Use more appropriate type for local variable
  ...
2018-06-13 09:52:54 +02:00
Philippe Antoine
b5b254300e Fix undefined shifts
- in x509_profile_check_pk_alg
- in x509_profile_check_md_alg
- in x509_profile_check_key

and in ssl_cli.c : unsigned char gets promoted to signed integer
2018-06-06 14:27:12 +02:00
Darryl Green
11999bb72e Fix minor code style issues 2018-05-15 09:21:57 +01:00
Andres Amaya Garcia
1f6301b3c8 Rename mbedtls_zeroize to mbedtls_platform_zeroize 2018-04-17 10:00:21 -05:00
Andres Amaya Garcia
e32df087fb Remove individual copies of mbedtls_zeroize()
This commit removes all the static occurrencies of the function
mbedtls_zeroize() in each of the individual .c modules. Instead the
function has been moved to utils.h that is included in each of the
modules.
2018-04-17 09:19:05 -05:00
Krzysztof Stachowiak
fe60132305 Move a buffer size test before the first relevant read 2018-04-05 16:53:35 +02:00
Gilles Peskine
15ad579895 Merge tag 'mbedtls-2.8.0' into iotssl-1381-x509-verify-refactor-restricted
Conflict resolution:

* ChangeLog
* tests/data_files/Makefile: concurrent additions, order irrelevant
* tests/data_files/test-ca.opensslconf: concurrent additions, order irrelevant
* tests/scripts/all.sh: one comment change conflicted with a code
  addition. In addition some of the additions in the
  iotssl-1381-x509-verify-refactor-restricted branch need support for
  keep-going mode, this will be added in a subsequent commit.
2018-03-23 02:16:22 +01:00
Gilles Peskine
5f1932817c Merge remote-tracking branch 'upstream-restricted/pr/398' into development-restricted-proposed 2018-03-13 17:18:06 +01:00
Manuel Pégourié-Gonnard
e57d7438b0 Improve documentation of some internal functions 2018-03-07 10:00:57 +01:00
Manuel Pégourié-Gonnard
05c00ed8b2 Fix some more MSVC size_t -> int warnings 2018-03-06 11:48:50 +01:00
Manuel Pégourié-Gonnard
f5bb78183a Fix MSVC warnings
library\x509_crt.c(2137): warning C4267: 'function' : conversion from 'size_t' to 'int', possible loss of data
library\x509_crt.c(2265): warning C4267: 'function' : conversion from 'size_t' to 'int', possible loss of data
2018-03-05 12:48:53 +01:00
Manuel Pégourié-Gonnard
05e464dff7 Merge branch 'development' into iotssl-1381-x509-verify-refactor-restricted
* development: (557 commits)
  Add attribution for #1351 report
  Adapt version_features.c
  Note incompatibility of truncated HMAC extension in ChangeLog
  Add LinkLibraryDependencies to VS2010 app template
  Add ChangeLog entry for PR #1382
  MD: Make deprecated functions not inline
  Add ChangeLog entry for PR #1384
  Have Visual Studio handle linking to mbedTLS.lib internally
  Mention in ChangeLog that this fixes #1351
  Add issue number to ChangeLog
  Note in the changelog that this fixes an interoperability issue.
  Style fix in ChangeLog
  Add ChangeLog entries for PR #1168 and #1362
  Add ChangeLog entry for PR #1165
  ctr_drbg: Typo fix in the file description comment.
  dhm: Fix typo in RFC 5114 constants
  tests_suite_pkparse: new PKCS8-v2 keys with PRF != SHA1
  data_files/pkcs8-v2: add keys generated with PRF != SHA1
  tests/pkcs5/pbkdf2_hmac: extend array to accommodate longer results
  tests/pkcs5/pbkdf2_hmac: add unit tests for additional SHA algorithms
  ...
2018-03-05 11:55:38 +01:00
Ron Eldor
85e1dcff6a Fix handshake failure in suite B
Fix handshake failure where PK key is translated as `MBEDTLS_ECKEY`
instead of `MBEDTLS_ECDSA`
2018-02-06 15:59:38 +02:00
Andres Amaya Garcia
849bc65bbf Fix x509_get_subject_alt_name to drop invalid tag
Fix the x509_get_subject_alt_name() function to not accept invalid
tags. The problem was that the ASN.1 class for tags consists of two
bits. Simply doing bit-wise and of the CONTEXT_SPECIFIC macro with the
input tag has the potential of accepting tag values 0x10 (private)
which would indicate that the certificate has an incorrect format.
2017-11-07 19:34:35 +00:00
Manuel Pégourié-Gonnard
3f81691d29 Revert to old behaviour of profile_check_key()
Was never documented to check for key alg compatibility, so should not start
doing so. Just stop relying on the pk_alg argument instead.
2017-10-26 10:24:16 +02:00
Manuel Pégourié-Gonnard
19773ff835 Avoid comparing size between RSA and EC keys 2017-10-24 10:51:26 +02:00
Manuel Pégourié-Gonnard
08c36635cb Avoid possible miscast of PK key
I don't think this can cause a crash as the member accessed is in the
beginning of the context, so wouldn't be outside of valid memory if the actual
context was RSA.

Also, the mismatch will be caught later when checking signature, so the cert
chain will be rejected anyway.
2017-10-18 14:57:11 +02:00
Manuel Pégourié-Gonnard
900fba616f Fix check_wildcard() calling convention
We shouldn't return a surprising value in case there is no wildcard and then
rely on the caller to ensure that this doesn't happen
2017-10-18 14:40:13 +02:00
Manuel Pégourié-Gonnard
08eacecc62 Fix some style issues and comment typos 2017-10-18 14:40:11 +02:00
Manuel Pégourié-Gonnard
bb216bd940 Fix MSVC 64-bit warnings
"conversion from size_t to int, possible loss of data"
2017-08-28 13:25:55 +02:00
Manuel Pégourié-Gonnard
daf049144e Rework state saving for verify_chain()
Child was almost redundant as it's already saved in ver_chain, except it was
multiplexed to also indicate whether an operation is in progress. This commit
removes it and introduces an explicit state variable instead.

This state can be useful later if we start returning IN_PROGRESS at other
points than find_parent() (for example when checking CRL).

Note that the state goes none -> find_parent and stays there until the context
is free(), as it's only on the first call that nothing was in progress.
2017-08-23 12:32:19 +02:00
Manuel Pégourié-Gonnard
a968843429 Improve some comments in verify_chain() 2017-08-23 11:37:22 +02:00
Manuel Pégourié-Gonnard
3627a8b2f6 Clarify state handling in find_parent(_in)() 2017-08-23 11:20:48 +02:00
Manuel Pégourié-Gonnard
83e923ba2b Better initialisation of ver_chain
Use dedicated function for consistency, and initialise flags to -1 as this is
the safe value.
2017-08-23 10:55:41 +02:00
Manuel Pégourié-Gonnard
15d7df2ba8 Introduce mbedtls_pk_restart_ctx and use it
The fact that you needed to pass a pointer to mbedtls_ecdsa_restart_ctx (or
that you needed to know the key type of the PK context) was a breach of
abstraction.

Change the API (and callers) now, and the implementation will be changed in
the next commit.
2017-08-17 15:16:11 +02:00
Manuel Pégourié-Gonnard
98a6778d47 Better document some function arguments 2017-08-17 10:52:20 +02:00
Manuel Pégourié-Gonnard
8b59049407 Make verify() actually restartable 2017-08-15 10:45:09 +02:00
Manuel Pégourié-Gonnard
c11e4baa63 Rework type for verify chain
- create container with length + table
- make types public (will be needed in restart context)
2017-08-15 10:44:13 +02:00
Manuel Pégourié-Gonnard
18547b5db6 Refactor find_parent() to merge two call sites 2017-08-15 10:44:13 +02:00
Manuel Pégourié-Gonnard
a4a5d1dbe6 Adapt function signatures to rs_ctx + ret 2017-08-15 10:44:13 +02:00
Manuel Pégourié-Gonnard
be4ff42fe4 Call crt_check_signature from one place only 2017-08-15 10:44:13 +02:00
Manuel Pégourié-Gonnard
d19a41d9aa Add tests for verify_restartable()
For selection of test cases, see comments added in the commit.

It makes the most sense to test with chains using ECC only, so for the chain
of length 2 we use server10 -> int-ca3 -> int-ca2 and trust int-ca2 directly.

Note: server10.crt was created by copying server10_int3_int-ca2.crt and
manually truncating it to remove the intermediates. That base can now be used
to create derived certs (without or with a chain) in a programmatic way.
2017-08-15 10:44:08 +02:00
Manuel Pégourié-Gonnard
bc3f44ae9c Introduce mbedtls_x509_crt_verify_restartable() 2017-08-09 11:44:53 +02:00
Manuel Pégourié-Gonnard
24611f9383 Remove redundant variable
path_cnt was always chain_len - 1 in the loop body
2017-08-09 10:28:07 +02:00
Manuel Pégourié-Gonnard
562df401d3 Improve some comments, fix some typos+whitespace 2017-08-08 18:17:53 +02:00
Manuel Pégourié-Gonnard
66a36b03c6 Update comments 2017-08-08 11:06:51 +02:00
Manuel Pégourié-Gonnard
505c3953c7 Make the ver_chain length explicit 2017-08-08 11:06:51 +02:00
Manuel Pégourié-Gonnard
a707e1d1ef Extract code to separate function for readablity 2017-08-08 11:06:51 +02:00
Manuel Pégourié-Gonnard
ce6e52ff42 Make verify_chain() iterative 2017-08-08 11:06:51 +02:00
Manuel Pégourié-Gonnard
f86f491f25 Rm unneeded function arguments & update comments 2017-08-08 11:06:51 +02:00
Manuel Pégourié-Gonnard
c547d1ab1f Start using an explicit stack for callback info
This is the first step towards making verify_chain() iterative. While from a
readability point of view the current recursive version is fine, one of the
goals of this refactoring is to prepare for restartable ECC integration, which
will need the explicit stack anyway.
2017-08-08 11:06:51 +02:00
Manuel Pégourié-Gonnard
a468eb1764 verify_name(): factor duplicated code to function 2017-08-08 11:06:51 +02:00
Manuel Pégourié-Gonnard
1300e99eb1 Extract name checking to separate function
Just copy-paste and unindent
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
6368612a8f Move code to separate function for readability 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
27e94797aa Simplify handling of locally trusted EE certs
Though this might require one more walk of the list in some cases,
this avoid having a check for that deep inside check_parent().
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
bdc5440232 Update comments 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
cb39610093 Finally merge the remains of top() into child() 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
63642776b1 Let verify_top() handle only the parent
It felt wrong for it to call the vrfy callback on two certs.
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
6e786747fb Move top()'s checks on child to child() 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
784aee3366 Move other special case from top() to child() 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
b9983be73a Move one special case from verify_top() to child() 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
66fac75f8b Merge duplicated checks between child() and top() 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
58dcd2d9b2 Get rid of unused variables/arguments 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
8f8c282de9 Merge near-duplicated (grand)parent finding code
Besides avoiding near-duplication, this avoids having three generations of
certificate (child, parent, grandparent) in one function, with all the
off-by-one opportunities that come with it.

This also allows to simplify the signature of verify_child(), which will be
done in next commit.
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
f82a4d5aba Factor duplicated code into function 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
32fdc60c7b Unnest code in verify_top()
We now know that trust_ca != NULL till the end of the function
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
6038cb6909 Remove duplicate parent-searching in verify_top() 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
2f09d59456 Add badkey-skipping to find_parent()
This is the last step towards removing the now-duplicated parent-searching
code in verify_top()
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
3e329b8e8d Add badtime-skipping feature to new function
This is from the morally 5th (and soon obsolete) invocation of this function
in verify_top().

Doing this badtime-skipping when we search for a parent in the provided chain
is a change of behaviour, but it's backwards-compatible: it can only cause us
to accept valid chains that we used to reject before. Eg if the peer has a
chain with two version of an intermediate certificate with different validity
periods, the first non valid and the second valid - such cases are probably
rare or users would have complained already, but it doesn't hurt to handle it
properly as it allows for more uniform code.
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
9c6118c498 Factor one more occurrence of code into function
This may look like a behaviour change because one check has been added to the
function that was previously done in only one of the 3 call sites. However it
is not, because:
- for the 2 call sites in verify(), the test always succeeds as path_cnt is 0.
- for the call site in verify_child(), the same test was done later anyway in
  verify_top()
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
2f1c33dc33 Factor repeated code into function
There are 3 instance that were replaced, but 2 instances of variants of this
function exist and will be handled next (the extra parameter that isn't used
so far is in preparation for that):
- one in verify_child() where path_cnt constraint is handled too
- one in verify_top() where there is extra logic to skip parents that are
  expired or future, but only if there are better parents to be found
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
17f4a6a609 Take shortcut for directly trusted EE cert
This is a slight change of behaviour in that the previous condition was:
- same subject
- signature matches
while the new condition is:
- exact same certificate

However the documentation for mbedtls_x509_crt_verify() (note on trust_ca)
mentions the new condition, so code that respected the documentation will keep
working.

In addition, this is a bit faster as it doesn't check the self-signature
(which never needs to be checked for certs in the trusted list).
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
c61e5c9304 Don't search twice for a non-existing parent 2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
b8acfd2ba8 Fix calls to check_parent()
When we're looking for a parent, in trusted CAs, 'top' should be 1.

This only impacted which call site for verify_top() was chosen, and the error
was then fixed inside verify_top() by iterating over CAs again, this time
correctly setting 'top' to 1.
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
35407c7764 Add comments on chain verification cases
This is the beginning of a series of commits refactoring the chain
building/verification functions in order to:
- make it simpler to understand and work with
- prepare integration of restartable ECC
2017-08-08 11:06:50 +02:00
Manuel Pégourié-Gonnard
329e78c7fa Improve handling of md errors in X.509
md() already checks for md_info == NULL. Also, in the future it might also
return other errors (eg hardware errors if acceleration is used), so it make
more sense to check its return value than to check for NULL ourselves and then
assume no other error can occur.

Also, currently, md_info == NULL can never happen except if the MD and OID modules
get out of sync, or if the user messes with members of the x509_crt structure
directly.

This commit does not change the current behaviour, which is to treat MD errors
the same way as a bad signature or no trusted root.
2017-08-08 11:06:49 +02:00