Commit graph

8102 commits

Author SHA1 Message Date
Manuel Pégourié-Gonnard
f0bbd7e3fd Misc documentation fixes/improvements. 2018-10-15 13:22:41 +02:00
Manuel Pégourié-Gonnard
6346a75dfb Merge branch 'development' into iotssl-1260-non-blocking-ecc-restricted
* development:
  ssl-opt.sh: change expected output for large srv packet test with SSLv3
  Adapt ChangeLog
  Fix bug in SSL ticket implementation removing keys of age < 1s
  ssl-opt.sh: Add DTLS session resumption tests
  Add ChangeLog entry
  Fix typo
  Fix hmac_drbg failure in benchmark, with threading
  Remove trailing whitespace
  Remove trailing whitespace
  ssl_server2: add buffer overhead for a termination character
  Add missing large and small packet tests for ssl_server2
  Added buffer_size and response_size options for ssl-server2. Added appropriate tests.

Solving a conflict in tests/ssl-opt.sh: two set of tests were added at the
same place (just after large packets):
- restartable ECC tests (in this branch)
- server-side large packets (in development)

Resolution was to move the ECC tests after the newly added server large packet
ones.
2018-10-15 11:26:17 +02:00
Gilles Peskine
4899247bf2 Fix undefined behavior in unsigned-to-signed conversion
The code assumed that `int x = - (unsigned) u` with 0 <= u < INT_MAX
sets `x` to the negative of u, but actually this calculates
(UINT_MAX - u) and then converts this value to int, which overflows.
Cast to int before applying the unary minus operator to guarantee the
desired behavior.
2018-10-12 20:32:55 +02:00
Gilles Peskine
9b430704d1 Fix likely-harmless undefined behavior surrounding volatile
The code was making two unsequenced reads from volatile locations.
This is undefined behavior. It was probably harmless because we didn't
care in what order the reads happened and the reads were from ordinary
memory, but UB is UB and IAR8 complained.
2018-10-12 20:32:52 +02:00
Hanno Becker
0b44d5cc79 Zeroize sensitive data in aescrypt2 and crypt_and_hash examples
This commit replaces multiple `memset()` calls in the example
programs aes/aescrypt2.c and aes/crypt_and_hash.c by calls to
the reliable zeroization function `mbedtls_zeroize()`.

While not a security issue because the code is in the example
programs, it's bad practice and should be fixed.
2018-10-12 16:54:29 +01:00
Hanno Becker
805f2e11bd Add missing zeroization of buffered handshake messages
This commit ensures that buffers holding fragmented or
future handshake messages get zeroized before they are
freed when the respective handshake message is no longer
needed. Previously, the handshake message content would
leak on the heap.
2018-10-12 16:50:37 +01:00
Andrzej Kurek
9580528248 ssl-opt.sh: fix typo in mtu settings 2018-10-11 08:55:37 -04:00
Andrzej Kurek
b459346f67 ssl-opt.sh: add a check for i686 targets
Run DTLS fragmenting tests on non-i686 targets only.
Remove reduntant gnutls requirements.
2018-10-11 08:43:30 -04:00
Andrzej Kurek
7782605491 ssl-opt.sh: add comments regarding ciphersuite forcing 2018-10-11 07:34:08 -04:00
Andrzej Kurek
748face36f ssl_tls: fix maximum output length
set maximum output length to MBEDTLS_SSL_OUT_CONTENT_LEN instead of
MBEDTLS_SSL_MAX_CONTENT_LEN.
2018-10-11 07:20:19 -04:00
Andrzej Kurek
7c6df832ed ssl-opt.sh: revert unnecessary "autoreduction" checks
return to the initial check for "resend"
2018-10-11 07:06:12 -04:00
Andrzej Kurek
7311c78074 ssl-opt.sh: force ciphersuites to reduce mtu size 2018-10-11 06:49:41 -04:00
Hanno Becker
780f0a4cc1 Reinitialize PK ctx in mbedtls_pk_parse_key before reuse are free
Context: This commit makes a change to mbedtls_pk_parse_key() which
is responsible for parsing of private keys. The function doesn't know
the key format in advance (PEM vs. DER, encrypted vs. unencrypted) and
tries them one by one, resetting the PK context in between.

Issue: The previous code resets the PK context through a call to
mbedtls_pk_free() along, lacking the accompanying mbedtls_pk_init()
call. Practically, this is not an issue because functionally
mbedtls_pk_free() + mbedtls_pk_init() is equivalent to mbedtls_pk_free()
with the current implementation of these functions, but strictly
speaking it's nonetheless a violation of the API semantics according
to which xxx_free() functions leave a context in uninitialized state.
(yet not entirely random, because xxx_free() functions must be idempotent,
so they cannot just fill the context they operate on with garbage).

Change: The commit adds calls to mbedtls_pk_init() after those calls
to mbedtls_pk_free() within mbedtls_pk_parse_key() after which the
PK context might still be used.
2018-10-11 11:31:15 +01:00
Hanno Becker
cfa2e33fd2 Omit runtime configuration of calloc/free if macro config enabled
This commit removes the definition of the API function

`mbedtls_platform_set_calloc_free()`

from `library/platform.c` in case the macros

`MBEDTLS_PLATFORM_CALLOC_MACRO`
`MBEDTLS_PLATFORM_FREE_MACRO`

for compile time configuration of calloc/free are set.

This is in line with the corresponding header `mbedtls/platform.h`
which declares `mbedtls_platform_set_calloc_free()` only if
`MBEDTLS_PLATFORM_{CALLOC/FREE}_MACRO` are not defined.

Fixes #1642.
2018-10-11 11:04:20 +01:00
Hanno Becker
e5fecec7bf Add test for MBEDTLS_PLATFORM_{CALLOC/FREE}_MACRO to all.sh
This commit adds a test to tests/scripts/all.sh exercising an
ASan build of the default configuration with

MBEDTLS_PLATFORM_MEMORY enabled,
MBEDTLS_PLATFORM_CALLOC_MACRO set to std calloc
MBEDTLS_PLATFORM_FREE_MACRO   set to std free

(This should functionally be indistinguishable from a default build)
2018-10-11 11:04:20 +01:00
Hanno Becker
8df10232cf Add explicit unsigned-to-signed integer conversion
The previous code triggered a compiler warning because of a comparison
of a signed and an unsigned integer.

The conversion is safe because `len` is representable by 16-bits,
hence smaller than the maximum integer.
2018-10-10 15:48:39 +01:00
Darryl Green
ac2ead0e68 Improve deterministic test for prime testing
Extend the mbedtls_mpi_is_prime_det test to check that it reports
the number as prime when testing rounds-1 rounds, then reports the
number as composite when testing the full number of rounds.
2018-10-09 16:36:53 +01:00
Darryl Green
e3f95ed25b Fix bias in random number generation in Miller-Rabin test
When a random number is generated for the Miller-Rabin primality test,
if the bit length of the random number is larger than the number being
tested, the random number is shifted right to have the same bit length.
This introduces bias, as the random number is now guaranteed to be
larger than 2^(bit length-1).

Changing this to instead zero all bits higher than the tested numbers
bit length will remove this bias and keep the random number being
uniformly generated.
2018-10-09 16:36:53 +01:00
Janos Follath
e0e7ddf99e Changelog: Add entry for prime validation fix 2018-10-09 16:36:53 +01:00
Janos Follath
a0b67c2f3e Bignum: Deprecate mbedtls_mpi_is_prime()
When using a primality testing function the tolerable error rate depends
on the scheme in question, the required security strength and wether it
is used for key generation or parameter validation. To support all use
cases we need more flexibility than what the old API provides.
2018-10-09 16:36:53 +01:00
Janos Follath
da31fa137a Bignum: Fix prime validation vulnerability
The input distribution to primality testing functions is completely
different when used for generating primes and when for validating
primes. The constants used in the library are geared towards the prime
generation use case and are weak when used for validation. (Maliciously
constructed composite numbers can pass the test with high probability)

The mbedtls_mpi_is_prime() function is in the public API and although it
is not documented, it is reasonable to assume that the primary use case
is validating primes. The RSA module too uses it for validating key
material.
2018-10-09 16:36:53 +01:00
Janos Follath
64eca05ec2 Bignum: Add tests for primality testing
Primality tests have to deal with different distribution when generating
primes and when validating primes.
These new tests are testing if mbedtls_mpi_is_prime() is working
properly in the latter setting.

The new tests involve pseudoprimes with maximum number of
non-witnesses. The non-witnesses were generated by printing them
from mpi_miller_rabin(). The pseudoprimes were generated by the
following function:

void gen_monier( mbedtls_mpi* res, int nbits )
{
    mbedtls_mpi p_2x_plus_1, p_4x_plus_1, x, tmp;

    mbedtls_mpi_init( &p_2x_plus_1 );
    mbedtls_mpi_init( &p_4x_plus_1 );
    mbedtls_mpi_init( &x ); mbedtls_mpi_init( &tmp );

    do
    {
        mbedtls_mpi_gen_prime( &p_2x_plus_1, nbits >> 1, 0,
                               rnd_std_rand, NULL );
        mbedtls_mpi_sub_int( &x, &p_2x_plus_1, 1 );
        mbedtls_mpi_div_int( &x, &tmp, &x, 2 );

        if( mbedtls_mpi_get_bit( &x, 0 ) == 0 )
            continue;

        mbedtls_mpi_mul_int( &p_4x_plus_1, &x, 4 );
        mbedtls_mpi_add_int( &p_4x_plus_1, &p_4x_plus_1, 1 );

        if( mbedtls_mpi_is_prime( &p_4x_plus_1, rnd_std_rand,
                                  NULL ) == 0 )
            break;

    } while( 1 );

    mbedtls_mpi_mul_mpi( res, &p_2x_plus_1, &p_4x_plus_1 );
}
2018-10-09 16:36:53 +01:00
Janos Follath
b728c29114 Bignum: Remove dead code
Both variables affected by the code are overwritten before their next
read.
2018-10-09 16:33:27 +01:00
Janos Follath
3332937538 Changelog: Add entry for prime test improvement 2018-10-09 16:33:27 +01:00
Janos Follath
b8fc1b02ee RSA: Use MBEDTLS_MPI_GEN_PRIME_FLAG_LOW_ERR 2018-10-09 16:33:27 +01:00
Janos Follath
a3cb7eb8ad Bignum: Add test for improved prime generation 2018-10-09 16:33:27 +01:00
Janos Follath
f301d23ceb Bignum: Improve primality test for FIPS primes
The FIPS 186-4 RSA key generation prescribes lower failure probability
in primality testing and this makes key generation slower. We enable the
caller to decide between compliance/security and performance.

This python script calculates the base two logarithm of the formulas in
HAC Fact 4.48 and was used to determine the breakpoints and number of
rounds:

def mrpkt_log_2(k, t):
    if t <= k/9.0:
        return 3*math.log(k,2)/2+t-math.log(t,2)/2+4-2*math.sqrt(t*k)
    elif t <= k/4.0:
        c1 = math.log(7.0*k/20,2)-5*t
        c2 = math.log(1/7.0,2)+15*math.log(k,2)/4.0-k/2.0-2*t
        c3 = math.log(12*k,2)-k/4.0-3*t
        return max(c1, c2, c3)
    else:
        return math.log(1/7.0)+15*math.log(k,2)/4.0-k/2.0-2*t
2018-10-09 16:33:27 +01:00
Andrzej Kurek
35f2f300ca ssl-opt.sh: change expected pattern from 'resend' to 'autoreduction' 2018-10-09 08:52:14 -04:00
Andrzej Kurek
ef43ce6e25 Dtls: change the way unlimited mtu is set for client hello messages 2018-10-09 08:24:12 -04:00
Hanno Becker
abe6003f5a Adapt ChangeLog 2018-10-09 12:44:47 +01:00
Hanno Becker
095d9cf58e Fix ordering of free()ing of internal structures in ssl_server2
If `MBEDTLS_MEMORY_BUFFER_ALLOC_C` is configured and Mbed TLS'
custom buffer allocator is used for calloc() and free(), the
read buffer used by the server example application is allocated
from the buffer allocator, but freed after the buffer allocator
has been destroyed. If memory backtracing is enabled, this leaves
a memory leak in the backtracing structure allocated for the buffer,
as found by valgrind.

Fixes #2069.
2018-10-09 12:44:42 +01:00
Andrzej Kurek
0fc9cf40cf ssl-opt.sh: increase proxy mtu sizes to contain entire datagrams 2018-10-09 03:09:41 -04:00
Hanno Becker
1624e2e8bb Avoid overly long lines X.509 DN attr array def in x509_create.c 2018-10-08 14:52:20 +01:00
Hanno Becker
35b6854e54 Replace reference to RFC 3280 by reference to newer RFC 5280 2018-10-08 14:47:38 +01:00
Hanno Becker
cfc47bab69 Correct some indentation and line lengths in x509_create.c 2018-10-08 14:45:42 +01:00
Hanno Becker
d355e69aed Rename tag to default_tag in x509_attr_descriptor_t 2018-10-08 14:44:32 +01:00
Hanno Becker
d0e21fbd27 Improve documentation of ASN.1 string-writing functions
- mbedtls_asn1_write_tagged_string()
- mbedtls_asn1_write_printable_string()
- mbedtls_asn1_write_utf8_string()
- mbedtls_asn1_write_ia5_string()
2018-10-08 14:44:28 +01:00
Hanno Becker
d2c9009e5a Improve documentation of x509_attr_descriptor_t 2018-10-08 14:42:34 +01:00
Hanno Becker
dc71ef8fcc Adapt ChangeLog 2018-10-08 13:51:38 +01:00
Hanno Becker
0c161d1956 Fix bounds check in ssl_parse_server_psk_hint()
In the previous bounds check `(*p) > end - len`, the computation
of `end - len` might underflow if `end` is within the first 64KB
of the address space (note that the length `len` is controlled by
the peer). In this case, the bounds check will be bypassed, leading
to `*p` exceed the message bounds by up to 64KB when leaving
`ssl_parse_server_psk_hint()`. In a pure PSK-based handshake,
this doesn't seem to have any consequences, as `*p*` is not accessed
afterwards. In a PSK-(EC)DHE handshake, however, `*p` is read from
in `ssl_parse_server_ecdh_params()` and `ssl_parse_server_dh_params()`
which might lead to an application crash of information leakage.
2018-10-08 13:40:50 +01:00
Gilles Peskine
695a34654a Add tests for PKCS#1 v1.5 decoding
Functional tests for various payload sizes and output buffer sizes.

When the padding is bad or the plaintext is too large for the output
buffer, verify that function writes some outputs. This doesn't
validate that the implementation is time-constant, but it at least
validates that it doesn't just return early without outputting anything.
2018-10-08 11:13:21 +02:00
Andrzej Kurek
948fe80f42 ssl-opt.sh: adjust test timeouts to fit slower targets 2018-10-06 05:07:47 -04:00
Gilles Peskine
ec2a5fdee1 PKCS#1 v1.5 decoding: fix empty payload case 2018-10-05 20:48:20 +02:00
Gilles Peskine
c5ccd7a1e7 Indicate the memory access variations in the changelog entry 2018-10-05 15:42:52 +02:00
Gilles Peskine
40b57f4acd Remove a remaining sensitive memory access in PKCS#1 v1.5 decryption 2018-10-05 15:35:03 +02:00
Gilles Peskine
85a7442753 mbedtls_rsa_rsaes_pkcs1_v15_decrypt: remove the variable p
Get rid of the variable p. This makes it more apparent where the code
accesses the buffer at an offset whose value is sensitive.

No intended behavior change in this commit.
2018-10-05 14:50:21 +02:00
Andrzej Kurek
6290dae909 Disable dtls fragmentation for ClientHello messages
Set the handshake mtu to unlimited when encountering a ClienHello message and
reset it to its previous value after writing the record.
2018-10-05 08:06:01 -04:00
Andrzej Kurek
52f8491dc2 ssl-opt.sh: adjust tests to fit slower targets
Adjust mtu sizes to be able to pass tests using a full configuration
2018-10-05 07:53:40 -04:00
Hanno Becker
617a321ed9 Adapt ChangeLog 2018-10-05 09:52:59 +01:00
Hanno Becker
30a95102b1 Fix memory leak and freeing without initialization in cert_write
* The variables `csr` and `issuer_crt` are initialized but not freed.
* The variable `entropy` is unconditionally freed in the cleanup section
  but there's a conditional jump to that section before its initialization.
  This cmmot Moves it to the other initializations happening before the
  first conditional jump to the cleanup section.

Fixes #1422.
2018-10-05 09:52:31 +01:00