Commit graph

214 commits

Author SHA1 Message Date
Gilles Peskine 9e4f77c606 New MD API: rename functions from _ext to _ret
The _ext suffix suggests "new arguments", but the new functions have
the same arguments. Use _ret instead, to convey that the difference is
that the new functions return a value.
2018-01-22 11:54:42 +01:00
Gilles Peskine d91f2a26cb Merge branch 'development' into iotssl-1251-2.7
Conflict resolution:

* ChangeLog: put the new entries in their rightful place.
* library/x509write_crt.c: the change in development was whitespace
  only, so use the one from the iotssl-1251 feature branch.
2018-01-19 11:25:10 +01:00
Hanno Becker 87ae197f3e Add explicit uint truncation casts
This commit adds some explicit downcasts from `size_t` to `uint8_t` in
the RSASSA signature encoding function `rsa_rsassa_pkcs1_v15_encode`.
The truncation is safe as it has been checked beforehand that the
respective values are in the range of a `uint8_t`.
2018-01-15 15:27:56 +00:00
Hanno Becker 71b0060af7 Merge branch 'development' into iotssl-247 2018-01-15 11:31:34 +00:00
Hanno Becker d4d60579e4 Address issues found by coverity
1) `mbedtls_rsa_import_raw` used an uninitialized return
   value when it was called without any input parameters.
   While not sensible, this is allowed and should be a
   succeeding no-op.

2) The MPI test for prime generation missed a return value
   check for a call to `mbedtls_mpi_shift_r`. This is neither
   critical nor new but should be fixed.

3) Both the RSA keygeneration example program and the
   RSA test suites contained code initializing an RSA context
   after a potentially failing call to CTR DRBG initialization,
   leaving the corresponding RSA context free call in the
   cleanup section of the respective function orphaned.
   While this defect existed before, Coverity picked up on
   it again because of newly introduced MPI's that were
   also wrongly initialized only after the call to CTR DRBG
   init. The commit fixes both the old and the new issue
   by moving the initializtion of both the RSA context and
   all MPI's prior to the first potentially failing call.
2018-01-10 07:30:47 +00:00
Hanno Becker 3a760a1857 Add size check for RSA modulus to mbedtls_rsa_complete
The function `mbedtls_rsa_complete` is supposed to guarantee that
RSA operations will complete without failure. In contrast, it does
not ensure consistency of parameters, which is the task of the
checking functions `rsa_check_pubkey` and `rsa_check_privkey`.

Previously, the maximum allowed size of the RSA modulus was checked
in `mbedtls_rsa_check_pubkey`. However, exceeding this size would lead
to failure of some RSA operations, hence this check belongs to
`mbedtls_rsa_complete` rather than `mbedtls_rsa_check_pubkey`.
This commit moves it accordingly.
2018-01-05 08:14:49 +00:00
Hanno Becker f8c028a2fb Minor corrections 2017-10-17 09:20:57 +01:00
Hanno Becker c36aab69b5 Swap D,E parameters in mbedtls_rsa_deduce_primes 2017-10-17 09:15:06 +01:00
Hanno Becker ebd2c024dc Don't require P,Q in rsa_private if neither CRT nor blinding used 2017-10-12 10:57:39 +01:00
Hanno Becker b82a5b554c Fix typos and mixup related to RSA_NO_CRT 2017-10-11 19:12:00 +01:00
Hanno Becker a565f54c4c Introduce new files rsa_internal.[ch] for RSA helper functions
This commit splits off the RSA helper functions into separate headers and
compilation units to have a clearer separation of the public RSA interface,
intended to be used by end-users, and the helper functions which are publicly
provided only for the benefit of designers of alternative RSA implementations.
2017-10-11 11:00:19 +01:00
Hanno Becker 705fc68d72 Unify sanity checks for RSA private and public keys 2017-10-10 18:01:25 +01:00
Hanno Becker e867489ff6 Remove outdated comments from mbedtls_rsa_complete 2017-10-10 17:56:14 +01:00
Hanno Becker 7f25f850ac Adapt uses of mbedtls_rsa_complete to removed PRNG argument 2017-10-10 16:56:22 +01:00
Hanno Becker f9e184b9df Remove PRNG argument from mbedtls_rsa_complete 2017-10-10 16:55:41 +01:00
Hanno Becker 68b4d58bd8 Remove PRNG argument from mbedtls_rsa_deduce_moduli
It is not necessary to pass a CSPRNG to `mbedtls_rsa_deduce_moduli`, as there
exist well-working static strategies, and even if a PRNG is preferred, a
non-secure one would be sufficient.

Further, the implementation is changed to use a static strategy for the choice
of candidates which according to some benchmarks even performs better than the
previous one using random candidate choices.
2017-10-10 16:39:10 +01:00
Hanno Becker 0f65e0ca03 Rename rsa_deduce_moduli to rsa_deduce_primes 2017-10-03 14:40:44 +01:00
Hanno Becker 8ba6ce4f4f Rename rsa_deduce_private to rsa_deduce_private_exponent 2017-10-03 14:40:43 +01:00
Hanno Becker 45a0ef32d9 Correct memory leak in mbedtls_rsa_validate_crt 2017-10-03 14:32:56 +01:00
Hanno Becker e58d38c66f Minor improvements 2017-10-03 07:59:29 +01:00
Hanno Becker 2b2f898cbd Streamline code-path in rsa_rsassa_pkcs1_v15_encode 2017-10-03 07:59:29 +01:00
Hanno Becker 64a8c0acd6 Verify PKCS1 v1.5 signature without parsing
This commit modifies the PKCS1 v1.5 signature verification function `mbedtls_rsa_rsassa_pkcs1_v15_verify` to prepare the
expected PKCS1-v1.5-encoded hash using the function also used by the signing routine `mbedtls_rsa_rsassa_pkcs1_v15_sign`
and comparing it to the provided byte-string afterwards. This comes at the benefits of (1) avoiding any error-prone
parsing, (2) removing the dependency of the RSA module on the ASN.1 parsing module, and (3) reducing code size.
2017-10-03 07:58:00 +01:00
Hanno Becker fdf38030de Outsource code for generating PKCS1 v1.5 encoding
This commit moves the code preparing PKCS1 v1.5 encoded hashes from `mbedtls_rsa_rsassa_pkcs1_v15_sign` to a separate
non-public function `rsa_rsassa_pkcs1_v15_encode`. This code-path will then be re-used by the signature verification function
`mbetls_rsa_rsassa_pkcs1_v15_verify` in a later commit.
2017-10-03 07:58:00 +01:00
Hanno Becker 171a8f1c95 Move constant time memcmp for signature verification
This commit replaces the ad-hoc code for constant-time double-checking the PKCS1 v1.5 RSA signature by an invocation of
`mbedtls_safer_memcmp`.
2017-10-03 07:58:00 +01:00
Hanno Becker b5beaa8995 Check that 1 < D, E < N in mbedtls_rsa_validate_params 2017-10-02 13:20:20 +01:00
Hanno Becker c6fc878eda Remove mbedtls_rsa_check_crt
This is no longer needed after the decision to not exhaustively validate private key material.
2017-10-02 13:20:15 +01:00
Hanno Becker 98838b04af Minor improvements 2017-10-02 13:17:01 +01:00
Hanno Becker 7471631dde Make input arguments to mbedtls_rsa_import_raw constant
Original intention was to be allowed to perform in-place operations like changing the byte-order before importing
parameters into an HSM. Now a copy is needed in this case, but there's no more danger of a user expecting the arguments
to be left untouched.
2017-10-02 13:17:01 +01:00
Hanno Becker bdefff1dde Change signature of mbedtls_rsa_deduce_private
Make input arguments constant and adapt the implementation to use a temporary instead of in-place operations.
2017-10-02 09:59:48 +01:00
Hanno Becker ba5b755f1a Change signature and semantics of mbedtls_rsa_deduce_moduli
Input arguments are marked as constant. Further, no double-checking is performed when a factorization of the modulus has
been found.
2017-10-02 09:55:49 +01:00
Hanno Becker 56bae95e1d Improve style and documentation, fix typo 2017-09-29 15:43:49 +01:00
Hanno Becker bead71752e Correct typo in rsa.c 2017-09-29 12:41:06 +01:00
Hanno Becker ba1ba11a98 Check that length is properly set in mbedtls_rsa_check_pubkey 2017-09-29 11:54:05 +01:00
Hanno Becker 2f8f06aa25 Don't always recompute context length in mbedtls_rsa_get_len
This commit changes the implementation of `mbedtls_rsa_get_len` to return
`ctx->len` instead of always re-computing the modulus' byte-size via
`mbedtls_mpi_size`.
2017-09-29 11:54:05 +01:00
Hanno Becker 2cca6f3290 Always deduce N from P, Q in mbedtls_rsa_complete
Previously, a parameter set of (-, P, Q, -, E) was completed, but (-, P, Q, D,
E) wasn't - this is odd.
2017-09-29 11:54:05 +01:00
Hanno Becker 45037ceac5 Add check for presence of relevant parameters in mbedtls_rsa_private
If CRT is used, check for the presence N, P, Q, D, E, DP, DQ and QP. If CRT is
not used, check for N, P, Q, D, E only.
2017-09-14 08:02:14 +01:00
Hanno Becker b269a8584a Change mbedtls_rsa_check_privkey to use new helper functions 2017-08-25 08:35:09 +01:00
Hanno Becker d9431a7817 Minor comments improvement 2017-08-25 08:35:09 +01:00
Hanno Becker d363799a9d Add mbedtls_rsa_validate_crt
This commit adds the function mbedtls_rsa_validate_crt for validating a set of CRT parameters. The function
mbedtls_rsa_check_crt is simplified accordingly.
2017-08-25 08:35:09 +01:00
Hanno Becker d56d83a7f3 Remove double-checking code from rsa_deduce_moduli and rsa_complete 2017-08-25 08:35:08 +01:00
Hanno Becker 750e8b4596 Rename rsa_check_params->rsa_validate_params and change error codes 2017-08-25 08:34:55 +01:00
Hanno Becker fb81c0ec2e Guard primality checks in RSA module by MBEDTLS_GENPRIME
Primality testing is guarded by the configuration flag MBEDTLS_GENPRIME and used in the new RSA helper functions. This
commit adds a corresponding preprocessor directive.
2017-08-24 06:55:11 +01:00
Hanno Becker ab3773123c Add support for alternative RSA implementations
Alternative RSA implementations can be provided by defining MBEDTLS_RSA_ALT in
config.h, defining an mbedtls_rsa_context struct in a new file rsa_alt.h and
re-implementing the RSA interface specified in rsa.h.

Through the previous reworkings, the adherence to the interface is the only
implementation obligation - in particular, implementors are free to use a
different layout for the RSA context structure.
2017-08-23 16:24:51 +01:00
Hanno Becker 6345dd33b9 Adapt rsa_check_privkey to deal with NO_CRT option 2017-08-23 16:17:28 +01:00
Hanno Becker bee3aaeb50 Adapt rsa_gen_key to deal with RSA_NO_CRT option 2017-08-23 16:17:28 +01:00
Hanno Becker dc95c890ad Adapt rsa_deduce_crt to deal with RSA_NO_CRT option 2017-08-23 16:17:28 +01:00
Hanno Becker 33c30a0c7e Adapt rsa_copy and rsa_free to deal with RSA_NO_CRT option 2017-08-23 16:17:28 +01:00
Hanno Becker 23344b5fcc Adapt rsa_complete to deal with RSA_NO_CRT option 2017-08-23 16:17:28 +01:00
Hanno Becker 83aad1fa86 Adapt gen_key example program to new RSA interface 2017-08-23 16:17:27 +01:00
Hanno Becker 3a701161ff Adapt RSA selftest to new RSA interface
This commit replaces direct manipulation of structure fields in the RSA selftest
by calls to the extended interface.
2017-08-23 15:07:40 +01:00