Commit graph

53 commits

Author SHA1 Message Date
Janos Follath d4ac4e037b
Merge pull request #736 from mpg/cf-varpos-copy-dev-restricted
Constant-flow copy of HMAC from variable position
2020-08-25 14:35:55 +01:00
Manuel Pégourié-Gonnard ba6fc9796a Fix a typo in a comment
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-08-24 12:59:55 +02:00
Dan Handley abccfc1684 Merge development into development-restricted
* development:
  Update copyright notices to use Linux Foundation guidance
  Undef ASSERT before defining it to ensure that no previous definition has sneaked in through included files.
  Add ChangeLog entry for X.509 CN-type vulnerability
  Improve documentation of cn in x509_crt_verify()
  Fix comparison between different name types
  Add test: DNS names should not match IP addresses
  Remove obsolete buildbot reference in compat.sh
  Fix misuse of printf in shell script
  Fix added proxy command when IPv6 is used
  Simplify test syntax
  Fix logic error in setting client port
  ssl-opt.sh: include test name in log files
  ssl-opt.sh: remove old buildbot-specific condition
  ssl-opt.sh: add proxy to all DTLS tests

Signed-off-by: Dan Handley <dan.handley@arm.com>
2020-08-20 11:07:12 +01:00
Manuel Pégourié-Gonnard de1cf2c5e1 Make mbedtls_ssl_cf_memcpy_offset() constant-flow
all.sh component test_valgrind_constant_flow is now passing.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-08-20 10:22:41 +02:00
Manuel Pégourié-Gonnard 7fe2c5f086 Add mbedtls_ssl_cf_memcpy_offset() with tests
The tests are supposed to be failing now (in all.sh component
test_memsan_constant_flow), but they don't as apparently MemSan doesn't
complain when the src argument of memcpy() is uninitialized, see
https://github.com/google/sanitizers/issues/1296

The next commit will add an option to test constant flow with valgrind, which
will hopefully correctly flag the current non-constant-flow implementation.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-08-19 11:56:02 +02:00
Manuel Pégourié-Gonnard 3c31afaca6 Use temporary buffer to hold the peer's HMAC
This paves the way for a constant-flow implementation of HMAC checking, by
making sure that the comparison happens at a constant address. The missing
step is obviously to copy the HMAC from the secret offset to this temporary
buffer with constant flow, which will be done in the next few commits.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-08-19 11:56:01 +02:00
Bence Szépkúti 1e14827beb Update copyright notices to use Linux Foundation guidance
As a result, the copyright of contributors other than Arm is now
acknowledged, and the years of publishing are no longer tracked in the
source files.

Also remove the now-redundant lines declaring that the files are part of
MbedTLS.

This commit was generated using the following script:

# ========================
#!/bin/sh

# Find files
find '(' -path './.git' -o -path './3rdparty' ')' -prune -o -type f -print | xargs sed -bi '

# Replace copyright attribution line
s/Copyright.*Arm.*/Copyright The Mbed TLS Contributors/I

# Remove redundant declaration and the preceding line
$!N
/This file is part of Mbed TLS/Id
P
D
'
# ========================

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
2020-08-19 10:35:41 +02:00
Gilles Peskine e900b59703
Merge pull request #719 from gabor-mezei-arm/689_zeroising_of_plaintext_buffers
Zeroising of plaintext buffers in mbedtls_ssl_read()
2020-08-12 18:51:42 +02:00
Manuel Pégourié-Gonnard f009542747 Add missing const for consistency
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-27 09:34:10 +02:00
Manuel Pégourié-Gonnard e747843903 Fix a whitespace issue
Co-authored-by: Janos Follath <janos.follath@arm.com>
2020-07-27 09:34:10 +02:00
Manuel Pégourié-Gonnard e0765f35d5 Use int ret = MBEDTLS_ERROR_CORRUPTION_DETECTED; idiom
Co-authored-by: Gilles Peskine <gilles.peskine@arm.com>
2020-07-27 09:34:10 +02:00
Manuel Pégourié-Gonnard 44c9fdde6e Check errors from the MD layer
Could be out-of-memory for some functions, accelerator issues for others.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:20 +02:00
Manuel Pégourié-Gonnard 9713e13e68 Remove unnecessary cast
This is C, not C++, casts between void * and other pointer types are free.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:19 +02:00
Manuel Pégourié-Gonnard baccf803ad Improve some comments and internal documentation
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:19 +02:00
Manuel Pégourié-Gonnard ed0e86428d Factor repeated condition to its own macro
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:19 +02:00
Manuel Pégourié-Gonnard 7a8b1e6b71 Implement cf_hmac() actually with constant flow
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-22 11:31:18 +02:00
gabor-mezei-arm a321413807
Zeroising of plaintext buffers to erase unused application data from memory
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
2020-07-15 14:14:41 +02:00
Manuel Pégourié-Gonnard 65a6fa3e26 Make cf_hmac() STATIC_TESTABLE
The test function now depends on MBEDTLS_TEST_HOOKS, which is enabled by
config.py full, and since there are already components in all.sh exercising
the full config, this test function is sill exercised even with this new
dependency.

Since this is the first time a test function depends on MBEDTLS_TEST_HOOKS,
fix a bug in check-names.sh that wasn't apparent so far: headers from
library/*.h were not considered when looking for macro definitions. This
became apparent because MBEDTLS_STATIC_TESTABLE is defined in library/common.h
and started being used in library/ssl_msg.c, so was flagged as a likely typo.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-15 12:26:21 +02:00
Manuel Pégourié-Gonnard 8aa29e382f Use existing implementation of cf_hmac()
Just move code from ssl_decrypt_buf() to the new cf_hmac() function and then
call cf_hmac() from there.

This makes the new cf_hmac() function used, opening the door for making it
static in the next commit. It also validates that its interface works for
using it in ssl_decrypt_buf().

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-15 12:26:21 +02:00
Manuel Pégourié-Gonnard 045f094c81 Add dummy constant-flow HMAC function with tests
The dummy implementation is not constant-flow at all for now, it's just
here as a starting point and a support for developing the tests and putting
the infrastructure in place.

Depending on the implementation strategy, there might be various corner cases
depending on where the lengths fall relative to block boundaries. So it seems
safer to just test all possible lengths in a given range than to use only a
few randomly-chosen values.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-15 12:25:52 +02:00
Manuel Pégourié-Gonnard 2df1f1f16f Factor repeated preprocessor condition to a macro
The condition is a complex and repeated a few times. There were already some
inconsistencies in the repetitions as some of them forgot about DES.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-07-09 12:13:31 +02:00
Manuel Pégourié-Gonnard 527b87890d
Merge pull request #3454 from gilles-peskine-arm/include-common-h-development
Include common.h from all library source files
2020-07-03 09:44:18 +02:00
Gilles Peskine db09ef6d22 Include common.h instead of config.h in library source files
In library source files, include "common.h", which takes care of
including "mbedtls/config.h" (or the alternative MBEDTLS_CONFIG_FILE)
and other things that are used throughout the library.

FROM=$'#if !defined(MBEDTLS_CONFIG_FILE)\n#include "mbedtls/config.h"\n#else\n#include MBEDTLS_CONFIG_FILE\n#endif' perl -i -0777 -pe 's~\Q$ENV{FROM}~#include "common.h"~' library/*.c 3rdparty/*/library/*.c scripts/data_files/error.fmt scripts/data_files/version_features.fmt

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2020-07-02 11:26:57 +02:00
Manuel Pégourié-Gonnard f4e3fc9133 Use starts/finish around Lucky 13 dummy compressions
Fixes #3246

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-06-15 11:55:53 +02:00
Hanno Becker f486e28694 Document precondition of nonce-generating function in ssl_msg.c
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:33:08 +01:00
Hanno Becker 15952814d8 Improve documentation of nonce-generating function in ssl_msg.c
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:31:46 +01:00
Hanno Becker 1cda2667af Spell out check for non-zero'ness
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:28:44 +01:00
Hanno Becker 16bf0e2346 Fix debug print of explicit IV
The previous version attempted to write the explicit IV from
the destination buffer before it has been written there.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:27:34 +01:00
Hanno Becker 7cca3589cb Fix indentation in debug statement in ssl_msg.c
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-04 13:27:22 +01:00
Hanno Becker ceef848eb6 Rename TLS 1.3 padding granularity macro
This is to avoid confusion with the class of macros

MBEDTLS_SSL_PROTO_TLS1_X

which have an underscore between major and minor version number.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-06-02 06:16:00 +01:00
Hanno Becker c3f7b0b16b Fix #endif indicator comment
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-31 08:51:29 +01:00
Hanno Becker 67a37db2d2 Add missing configuration guards to SSL record protection helpers
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-31 08:51:29 +01:00
Hanno Becker 13996927cb Introduce configuration option for TLS 1.3 padding granularity
TLS 1.3 record protection allows the addition of an arbitrary amount
of padding.

This commit introduces a configuration option

```
   MBEDTLS_SSL_TLS13_PADDING_GRANULARITY
```

The semantics of this option is that padding is chosen in a minimal
way so that the padded plaintext has a length which is a multiple of
MBEDTLS_SSL_TLS13_PADDING_GRANULARITY.

For example, setting MBEDTLS_SSL_TLS13_PADDING_GRANULARITY to 1024
means that padded plaintexts will have length 1024, 2048, ..., while
setting it to 1 means that no padding will be used.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-31 08:51:25 +01:00
Hanno Becker c0eefa8b92 Introduce helper function to retrieve explicit IV len for transform
The structure `mbedtls_ssl_transform` representing record protection
transformations should ideally be used through a function-based
interface only, as this will ease change of implementation as well
as the addition of new record protection routines in the future.

This commit makes a step in that direction by introducing the
helper function `ssl_transform_get_explicit_iv_len()` which
returns the size of the pre-expansion during record encryption
due to the potential addition of an explicit IV.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-28 10:32:23 +01:00
Hanno Becker 17263803aa Simplify AEAD nonce derivation
This commit simplifies nonce derivation for AEAD based record protection
routines in the following way.

So far, code distinguished between the cases of GCM+CCM and ChachaPoly:

- In the case of GCM+CCM, the AEAD nonce is the concatentation
  of a 4-byte Fixed IV and a dynamically chosen 8-byte IV which is prepended
  to the record. In Mbed TLS, this is always chosen to be the record sequence
  number, but it need not to.

- In the case of ChaChaPoly, the AEAD nonce is derived as

    `( 12-byte Fixed IV ) XOR ( 0 || 8-byte dynamic IV == record seq nr )`

  and the dynamically chosen IV is no longer prepended to the record.

This commit removes this distinction by always computing the record nonce
via the formula

  `IV == ( Fixed IV || 0 ) XOR ( 0 || Dynamic IV )`

The ChaChaPoly case is recovered in case `Len(Fixed IV) == Len(IV)`, and
GCM+CCM is recovered when `Len(IV) == Len(Fixed IV) + Len(Dynamic IV)`.

Moreover, a getter stub `ssl_transform_aead_dynamic_iv_is_explicit()`
is introduced which infers from a transform whether the dynamically
chosen part of the IV is explicit, which in the current implementation
of `mbedtls_ssl_transform` can be derived from the helper field
`mbedtls_ssl_transform::fixed_ivlen`.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-28 10:32:23 +01:00
Hanno Becker df8be226ba TLS record protection: Add helper function for nonce derivation
The computation of the per-record nonce for AEAD record protection
varies with the AEAD algorithm and the TLS version in use.
This commit introduces a helper function for the nonce computation
to ease readability of the quite monolithic record encrytion routine.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-28 10:32:23 +01:00
Hanno Becker bd5ed1d11b TLS record protection: Add explicit IV after record protection.
The previous record protection code added the explicit part of the
record nonce prior to encrypting the record. This temporarily leaves
the record structure in the undesireable state that the data outsie
of the interval `rec->data_offset, .., rec->data_offset + rec->data_len`
has already been written.

This commit moves the addition of the explicit IV past record encryption.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-28 10:32:23 +01:00
Hanno Becker 1cb6c2a69d TLS record protection: Rewrite AAD setup and add case of TLS 1.3
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-28 10:32:23 +01:00
Hanno Becker 9231340d71 Improve documentation of (D)TLSInnerPlaintext handling
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-28 10:32:23 +01:00
Hanno Becker ccc13d03c3 TLS 1.3: Implement TLSInnerPlaintext parsing/building
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-28 10:32:23 +01:00
Hanno Becker 581bc1b908 Remove ref to CID from inner plaintext parsing/building functions
The internal functions

  `ssl_cid_{build/parse}_inner_plaintext()`

implement the TLSInnerPlaintext mechanism used by DTLS 1.2 + CID
in order to allow for flexible length padding and to protect the
true content type of a record.

This feature is also present in TLS 1.3 support for which is under
development. As a preparatory step towards sharing the code between
the case of DTLS 1.2 + CID and TLS 1.3, this commit renames

   `ssl_cid_{build/parse}_inner_plaintext()`

to

   `ssl_{build/parse}_inner_plaintext()`.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2020-05-28 10:32:23 +01:00
Jaeden Amero 66e21efe47
Merge pull request #3163 from AndrzejKurek/variable-buffers-renegotiation
Variable buffers & renegotiation - fixes
2020-04-09 12:11:02 +01:00
Andrzej Kurek 90c6e84a9c
Split the maximum fragment length into two - an input and output MFL
Since the server might want to have a different maximum fragment length
for the outgoing messages than the negotiated one - introduce a new way of
computing it. This commit also adds additional ssl-opt.sh tests ensuring
that the maximum fragment lengths are set as expected. 
mbedtls_ssl_get_max_frag_len() is now a deprecated function,
being an alias to mbedtls_ssl_get_output_max_frag_len(). The behaviour
of this function is the same as before.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
2020-04-09 04:30:34 -04:00
Manuel Pégourié-Gonnard 243d70f2a5 Improve debug logging of client hard reconnect
The current logging was sub-standard, in particular there was no trace
whatsoever of the HelloVerifyRequest being sent. Now it's being logged with
the usual levels: 4 for full content, 2 return of f_send, 1 decision about
sending it (or taking other branches in the same function) because that's the
same level as state changes in the handshake, and also same as the "possible
client reconnect" message" to which it's the logical continuation (what are we
doing about it?).

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-03-31 12:33:57 +02:00
Manuel Pégourié-Gonnard 824655c837 Fix lack of cookie check on hard reconnect
Section 4.2.8 of RFC 6347 describes how to handle the case of a DTLS client
establishing a new connection using the same UDP quartet as an already active
connection, which we implement under the compile option
MBEDTLS_SSL_DLTS_CLIENT_PORT_REUSE. Relevant excerpts:

    [the server] MUST NOT destroy the existing
    association until the client has demonstrated reachability either by
    completing a cookie exchange or by completing a complete handshake
    including delivering a verifiable Finished message.
    [...]
    The reachability requirement prevents
    off-path/blind attackers from destroying associations merely by
    sending forged ClientHellos.

Our code chooses to use a cookie exchange for establishing reachability, but
unfortunately that check was effectively removed in a recent refactoring,
which changed what value ssl_handle_possible_reconnect() needs to return in
order for ssl_get_next_record() (introduced in that refactoring) to take the
proper action. Unfortunately, in addition to changing the value, the
refactoring also changed a return statement to an assignment to the ret
variable, causing the function to reach the code for a valid cookie, which
immediately destroys the existing association, effectively bypassing the
cookie verification.

This commit fixes that by immediately returning after sending a
HelloVerifyRequest when a ClientHello without a valid cookie is found. It also
updates the description of the function to reflect the new return value
convention (the refactoring updated the code but not the documentation).

The commit that changed the return value convention (and introduced the bug)
is 2fddd3765e, whose commit message explains the
change.

Note: this bug also indirectly caused the ssl-opt.sh test case "DTLS client
reconnect from same port: reconnect" to occasionally fail due to a race
condition between the reception of the ClientHello carrying a valid cookie and
the closure of the connection by the server after noticing the ClientHello
didn't carry a valid cookie after it incorrectly destroyed the previous
connection, that could cause that ClientHello to be invisible to the server
(if that message reaches the server just before it does `net_close()`). A
welcome side effect of this commit is to remove that race condition, as the
new connection will immediately start with a ClientHello carrying a valid
cookie in the SSL input buffer, so the server will not call `net_close()` and
not risk discarding a better ClientHello that arrived in the meantime.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-03-27 10:50:05 +01:00
Manuel Pégourié-Gonnard 21d1cbccda
Merge pull request #2262 from andresag01/iotssl-2544-deprecate-record-accel
Fix compilation failure when MBEDTLS_SSL_HW_RECORD_ACCEL is enabled
2020-03-16 10:37:16 +01:00
Darryl Green b33cc7688e
Add I/O buffer length fields to mbedtls_ssl_context
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
Signed-off-by: Darryl Green <darryl.green@arm.com>
2020-03-03 10:44:49 -05:00
Manuel Pégourié-Gonnard e07bc20155 Fix compile errors with MBEDTLS_SSL_HW_RECORD_ACCEL
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
2020-02-26 09:53:42 +01:00
Hanno Becker 9d062f9cd7 Move ssl_mac() from ssl_tls.c to ssl_msg.c 2020-02-07 11:38:03 +00:00
Hanno Becker f1a3828ad8 Adapt preamble for newly created ssl_msg.c 2020-02-05 16:14:29 +00:00