Commit graph

453 commits

Author SHA1 Message Date
Janos Follath 3fbdadad7b SSL: Make use of the new ECDH interface
The SSL module accesses ECDH context members directly. This can't work
with the new context, where we can't make any assumption about the
implementation of the context.

This commit makes use of the new functions to avoid accessing ECDH
members directly. The only members that are still accessed directly are
the group ID and the point format and they are independent from the
implementation.
2018-12-06 12:22:46 +00:00
Hanno Becker bc2498a9ff Style: Add numerous comments indicating condition guarded by #endif 2018-08-28 10:13:29 +01:00
Hanno Becker 327c93b182 Add parameter to ssl_read_record() controlling checksum update
Previously, mbedtls_ssl_read_record() always updated the handshake
checksum in case a handshake record was received. While desirable
most of the time, for the CertificateVerify message the checksum
update must only happen after the message has been fully processed,
because the validation requires the handshake digest up to but
excluding the CertificateVerify itself. As a remedy, the bulk
of mbedtls_ssl_read_record() was previously duplicated within
ssl_parse_certificate_verify(), hardening maintenance in case
mbedtls_ssl_read_record() is subject to changes.

This commit adds a boolean parameter to mbedtls_ssl_read_record()
indicating whether the checksum should be updated in case of a
handshake message or not. This allows using it also for
ssl_parse_certificate_verify(), manually updating the checksum
after the message has been processed.
2018-08-17 16:52:08 +01:00
Hanno Becker 198594709b Store outgoing record sequence number outside record buffer
This commit is another step towards supporting the packing of
multiple records within a single datagram.

Previously, the incremental outgoing record sequence number was
statically stored within the record buffer, at its final place
within the record header. This slightly increased efficiency
as it was not necessary to copy the sequence number when writing
outgoing records.

When allowing multiple records within a single datagram, it is
necessary to allow the position of the current record within the
datagram buffer to be flexible; in particular, there is no static
address for the record sequence number field within the record header.

This commit introduces an additional field `cur_out_ctr` within
the main SSL context structure `mbedtls_ssl_context` to keep track
of the outgoing record sequence number independent of the buffer used
for the current record / datagram. Whenever a new record is written,
this sequence number is copied to the the address `out_ctr` of the
sequence number header field within the current outgoing record.
2018-08-17 15:40:35 +01:00
Manuel Pégourié-Gonnard 87a346f64e Always save flight first, (re)send later
This will allow fragmentation to always happen in the same place, always from
a buffer distinct from ssl->out_msg, and with the same way of resuming after
returning WANT_WRITE
2018-08-16 10:01:10 +02:00
Manuel Pégourié-Gonnard 31c1586893 Start separating handshake from record writing 2018-08-16 10:00:27 +02:00
Jaeden Amero cac0c1a250 Merge remote-tracking branch 'upstream-public/pr/1378' into development 2018-08-10 10:59:53 +01:00
Simon Butcher df15356259 Merge remote-tracking branch 'public/pr/1663' into development 2018-07-19 19:48:10 +01:00
Simon Butcher e7aeef09ee Merge remote-tracking branch 'public/pr/536' into development 2018-07-10 15:24:26 +01:00
Ron Eldor 755bb6af5f Add ecc extensions only if ecc ciphersuite is used
Fix compliancy to RFC4492. ECC extensions should be included
only if ec ciphersuites are used. Interoperability issue with
bouncy castle. #1157
2018-06-21 16:35:26 +03:00
Angus Gratton d8213d00db Let MBEDTLS_SSL_MAX_CONTENT_LEN to be split into outward & inward sizes
For the situation where the mbedTLS device has limited RAM, but the
other end of the connection doesn't support the max_fragment_length
extension. To be spec-compliant, mbedTLS has to keep a 16384 byte
incoming buffer. However the outgoing buffer can be made smaller without
breaking spec compliance, and we save some RAM.

See comments in include/mbedtls/config.h for some more details.

(The lower limit of outgoing buffer size is the buffer size used during
handshake/cert negotiation. As the handshake is half-duplex it might
even be possible to store this data in the "incoming" buffer during the
handshake, which would save even more RAM - but it would also be a lot
hackier and error-prone. I didn't really explore this possibility, but
thought I'd mention it here in case someone sees this later on a mission
to jam mbedTLS into an even tinier RAM footprint.)
2018-06-18 20:51:51 +10:00
Simon Butcher 600c5e6d20 Compilation warning fixes on 32b platfrom with IAR
Fix compilation warnings with IAR toolchain, on 32 bit platform.
Reported by rahmanih in #683

This is based on work by Ron Eldor in PR #750, some of which was independently
fixed by Azim Khan and already merged in PR #1646.
2018-06-17 17:24:56 +01:00
Simon Butcher 5f57f1e3cc Merge remote-tracking branch 'public/pr/1270' into development 2018-06-15 14:17:31 +01:00
Gilles Peskine 0a8352b4c2 Fix harmless use of uninitialized memory in ssl_parse_encrypted_pms
In ssl_parse_encrypted_pms, some operational failures from
ssl_decrypt_encrypted_pms lead to diff being set to a value that
depended on some uninitialized unsigned char and size_t values. This didn't
affect the behavior of the program (assuming an implementation with no
trap values for size_t) because all that matters is whether diff is 0,
but Valgrind rightfully complained about the use of uninitialized
memory. Behave nicely and initialize the offending memory.
2018-06-13 18:21:25 +02:00
Philippe Antoine 747fd53938 Fixes different off by ones 2018-06-05 16:13:10 +02:00
Gilles Peskine 1febfef561 Rename mbedtls_ssl_async_{get,set}_data for clarity
Rename to mbedtls_ssl_get_async_operation_data and
mbedtls_ssl_set_async_operation_data so that they're about
"async operation data" and not about some not-obvious "data".
2018-04-30 11:54:39 +02:00
Gilles Peskine 8f97af7ea3 Don't pass the async config data to async callbacks
The config data is in the SSL config, so callbacks can retrieve it
from there, with the new function mbedtls_ssl_conf_get_async_config_data.
2018-04-26 11:46:10 +02:00
Gilles Peskine e141638868 Finish writing an unfinished comment 2018-04-26 10:23:34 +02:00
Gilles Peskine 0fd90dd713 ssl_prepare_server_key_exchange: clarify where the signature is written 2018-04-26 10:00:40 +02:00
Gilles Peskine 22e695fc5a Be more precise about when a variable is unused 2018-04-26 10:00:40 +02:00
Gilles Peskine ad28bf0e58 Documentation improvements 2018-04-26 10:00:40 +02:00
Gilles Peskine 168dae8567 Comment formatting and whitespace fixes 2018-04-26 10:00:40 +02:00
Gilles Peskine df13d5c7a6 Pass the SSL context to async callbacks
When a handshake step starts an asynchronous operation, the
application needs to know which SSL connection the operation is for,
so that when the operation completes, the application can wake that
connection up. Therefore the async start callbacks need to take the
SSL context as an argument. It isn't enough to let them set a cookie
in the SSL connection, the application needs to be able to find the
right SSL connection later.

Also pass the SSL context to the other callbacks for consistency. Add
a new field to the handshake that the application can use to store a
per-connection context. This new field replaces the former
context (operation_ctx) that was created by the start function and
passed to the resume function.

Add a boolean flag to the handshake structure to track whether an
asynchronous operation is in progress. This is more robust than
relying on the application to set a non-null application context.
2018-04-26 10:00:40 +02:00
Gilles Peskine 2e33337570 Fix invalid data being accepted in RSA-decryption-based ciphersuites
In the refactoring of ssl_parse_encrypted_pms, I advertently broke the
case when decryption signalled an error, with the variable ret getting
overwritten before calculating diff. Move the calculation of diff
immediately after getting the return code to make the connection more
obvious. Also move the calculation of mask immediately after the
calculation of diff, which doesn't change the behavior, because I find
the code clearer that way.
2018-04-26 10:00:39 +02:00
Gilles Peskine b74a1c73b1 Rename MBEDTLS_SSL_ASYNC_PRIVATE_C to MBEDTLS_SSL_ASYNC_PRIVATE
This is an optional feature, not a module of its own, so don't call it
MBEDTLS_xxx_C and put it in the appropriate section of config.h.
2018-04-26 10:00:39 +02:00
Gilles Peskine f112725487 Style and grammar fixes 2018-04-26 10:00:39 +02:00
Gilles Peskine b44692f126 Merge branch 'mbedtls_ssl_get_key_exchange_md_ssl_tls-return_hashlen' into tls_async_server-2.9
Conflict resolution:
* ChangeLog: put the new entry from my branch in the proper place.
* include/mbedtls/error.h: counted high-level module error codes again.
* include/mbedtls/ssl.h: picked different numeric codes for the
  concurrently added errors; made the new error a full sentence per
  current standards.
* library/error.c: ran scripts/generate_errors.pl.
* library/ssl_srv.c:
    * ssl_prepare_server_key_exchange "DHE key exchanges": the conflict
      was due to style corrections in development
      (4cb1f4d49c) which I merged with
      my refactoring.
    * ssl_prepare_server_key_exchange "For key exchanges involving the
      server signing", first case, variable declarations: merged line
      by line:
        * dig_signed_len: added in async
        * signature_len: removed in async
        * hashlen: type changed to size_t in development
        * hash: size changed to MBEDTLS_MD_MAX_SIZE in async
        * ret: added in async
    * ssl_prepare_server_key_exchange "For key exchanges involving the
      server signing", first cae comment: the conflict was due to style
      corrections in development (4cb1f4d49c)
      which I merged with my comment changes made as part of refactoring
      the function.
    * ssl_prepare_server_key_exchange "Compute the hash to be signed" if
      `md_alg != MBEDTLS_MD_NONE`: conflict between
      ebd652fe2d
      "ssl_write_server_key_exchange: calculate hashlen explicitly" and
      46f5a3e9b4 "Check return codes from
      MD in ssl code". I took the code from commit
      ca1d742904 made on top of development
      which makes mbedtls_ssl_get_key_exchange_md_ssl_tls return the
      hash length.
* programs/ssl/ssl_server2.c: multiple conflicts between the introduction
  of MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS and new auxiliary functions and
  definitions for async support, and the introduction of idle().
    * definitions before main: concurrent additions, kept both.
    * main, just after `handshake:`: in the loop around
      mbedtls_ssl_handshake(), merge the addition of support for
      MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS and SSL_ASYNC_INJECT_ERROR_CANCEL
      with the addition of the idle() call.
    * main, if `opt.transport == MBEDTLS_SSL_TRANSPORT_STREAM`: take the
      code from development and add a check for
      MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS.
    * main, loop around mbedtls_ssl_read() in the datagram case:
      take the code from development and add a check for
      MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS; revert to a do...while loop.
    * main, loop around mbedtls_ssl_write() in the datagram case:
      take the code from development and add a check for
      MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS; revert to a do...while loop.
2018-04-26 10:00:27 +02:00
Andres Amaya Garcia 8491406803 Remove preprocessor directives around platform_util.h include 2018-04-24 08:40:46 -05:00
Gilles Peskine ca1d742904 mbedtls_ssl_get_key_exchange_md_tls1_2: return hashlen
In mbedtls_ssl_get_key_exchange_md_tls1_2, add an output parameter for
the hash length. The code that calls this function can currently do
without it, but it will need the hash length in the future, when
adding support for a third-party callback to calculate the signature
of the hash.
2018-04-24 11:53:22 +02:00
Gilles Peskine 2c6078ed3b SSL asynchronous decryption (server side)
Support SSL asynchronous private operation for the case of a
decryption operation on a server.
2018-04-24 09:36:36 +02:00
Gilles Peskine bcd98a5306 ssl_parse_encrypted_pms refactor: prepare, decrypt, return
Reorganize ssl_parse_encrypted_pms so that it first prepares the
ciphertext to decrypt, then decrypts it, then returns either the
decrypted premaster secret or random data in an appropriate manner.

This is in preparation for allowing the private key operation to be
offloaded to an external cryptographic module which can operate
asynchronously. The refactored code no longer calculates state before
the decryption that needs to be saved until after the decryption,
which allows the decryption to be started and later resumed.
2018-04-24 09:36:36 +02:00
Gilles Peskine 422ccabe29 ssl_parse_encrypted_pms refactor: prepare for remote private key
Use the public key to extract metadata rather than the public key.
Don't abort early if there is no private key.

This is in preparation for allowing the private key operation to be
offloaded to an external cryptographic module.
2018-04-24 09:36:36 +02:00
Gilles Peskine f9f15ae5a1 ssl_write_server_key_exchange refactor: don't use p at all
Use ssl->out_msglen as the cursor in ssl->out_msg throughout, rather
than switching a between pointer and an offset.
2018-04-24 09:36:36 +02:00
Gilles Peskine d3eb0619a6 ssl_write_server_key_exchange refactor: minor cleanup
Clean up some debug messages and improve some comments.
2018-04-24 09:36:36 +02:00
Gilles Peskine ebd30ae205 ssl_write_server_key_exchange refactor: ssl_resume_server_key_exchange
Continue clarifying the control flow. This gets rid of the last goto
introduced by the initial code for asynchronous signature support.
2018-04-24 09:36:36 +02:00
Gilles Peskine d04d292b64 Get rid of useless handshake field out_async_start
The location where the signature goes is now tracked via
ssl->out_msglen, which makes ssl->handshake->out_async_start redundant.
2018-04-24 09:36:36 +02:00
Gilles Peskine 7ab013a08a ssl_write_server_key_exchange refactor: move signature_len out
Move the writing of signature_len out of
ssl_prepare_server_key_exchange. This simplifies the control flow (one
less goto).
2018-04-24 09:36:36 +02:00
Gilles Peskine 1004c19ed0 ssl_write_server_key_exchange refactor: don't use p in the signing phase
This is in preparation of further splitting ssl_write_server_key_exchange
into several functions.
2018-04-24 09:36:36 +02:00
Gilles Peskine 184a3faa8a ssl_write_server_key_exchange refactor: create ssl_prepare_server_key_exchange
This is in the process of splitting ssl_write_server_key_exchange
into several functions.
2018-04-24 09:36:36 +02:00
Gilles Peskine 3ce9b900d2 ssl_write_server_key_exchange refactor: remove dig_signed_len
Simplify the redundant varaible dig_signed_len away.

This is in preparation for splitting ssl_write_server_key_exchange
into several functions.
2018-04-24 09:36:36 +02:00
Gilles Peskine 4bf9a28d1d SSL asynchronous signature: first implementation
Implement SSL asynchronous private operation for the case of a
signature operation in a server.

This is a first implementation. It is functional, but the code is not
clean, with heavy reliance on goto.
2018-04-24 09:36:06 +02:00
Gilles Peskine ebd652fe2d ssl_write_server_key_exchange: calculate hashlen explicitly
The pk layer can infer the hash length from the hash type. Calculate
it explicitly here anyway because it's needed for debugging purposes,
and it's needed for the upcoming feature allowing the signature
operation to be offloaded to an external cryptographic processor, as
the offloading code will need to know what length hash to copy.
2018-04-24 09:34:38 +02:00
Gilles Peskine e1efdf912f ssl_write_server_key_exchange: don't hard-code max hash size 2018-04-24 09:32:29 +02:00
Gilles Peskine e198df53a0 ssl_pick_cert: use the public key for can_do
This is in preparation for support of external private key operations,
where there is no private key object.
2018-04-24 09:32:29 +02:00
Gilles Peskine fe1c0937d7 ssl_write_server_key_exchange refactor: remove redundant variable n
Remove redundant variable n, which counts in parallel to p. Having
both adds the burden of keeping them in synch for no benefit.
2018-04-24 09:32:28 +02:00
Gilles Peskine 81d4e899a4 Don't rely on private key metadata in SSL
In SSL, don't use mbedtls_pk_ec or mbedtls_pk_rsa on a private
signature or decryption key (as opposed to a public key or a key used
for DH/ECDH). Extract the data (it's the same data) from the public
key object instead. This way the code works even if the private key is
opaque or if there is no private key object at all.

Specifically, with an EC key, when checking whether the curve in a
server key matches the handshake parameters, rely only on the offered
certificate and not on the metadata of the private key.
2018-04-24 09:26:03 +02:00
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
Hanno Becker 2bd57578af Merge branch 'development' into iotssl-1204 2018-03-28 14:52:35 +01:00
Jaeden Amero 784de59ccd Merge remote-tracking branch 'upstream-restricted/pr/410' into development-restricted
- Resolve ChangeLog conflicts
- Update Doxygen warning block in dhm.h to render correctly
- Prefix the exported identifier deprecated_constant_t with mbedtls_
2018-01-26 18:43:04 +00:00