Commit Graph

433 Commits

Author SHA1 Message Date
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
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
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
Jaeden Amero
66954e1c1f Merge branch 'development' into development-restricted 2018-01-25 17:28:31 +00:00
Jaeden Amero
005239e3ed Merge remote-tracking branch 'upstream-public/pr/1294' into development 2018-01-25 14:47:39 +00:00
Gilles Peskine
41b40e6463 Merge remote-tracking branch 'upstream-restricted/pr/441' into development-restricted 2018-01-23 00:59:51 +01:00
Gilles Peskine
aaaa98cd60 Merge branch 'development-proposed' into development-restricted 2018-01-23 00:59:17 +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
Manuel Pégourié-Gonnard
239987fd31 Fix heap-buffer overread in ALPN ext parsing 2018-01-09 13:48:38 +01:00
Gilles Peskine
1a2640c025 Merge branch 'iotssl-1368-unsafe-bounds-check-psk-identity-merge' into development-restricted 2017-11-23 18:58:30 +01:00
Hanno Becker
27b34d5bad Wrong identifier used to check Encrypt-then-MAC flag
This commit fixes a comparison of ssl_session->encrypt_then_mac against the
ETM-unrelated constant MBEDTLS_SSL_EXTENDED_MS_DISABLED. Instead,
MBEDTLS_SSL_ETM_DISABLED should be used.

The typo is has no functional effect since both constants have the same value 0.
2017-10-20 14:24:51 +01:00
Ron Eldor
73a381772b Parse Signature Algorithm ext when renegotiating
Signature algorithm extension was skipped when renegotiation was in
progress, causing the signature algorithm not to be known when
renegotiating, and failing the handshake. Fix removes the renegotiation
step check before parsing the extension.
2017-10-12 23:21:37 +01:00
Ron Eldor
8dd73e62d2 Parse Signature Algorithm ext when renegotiating
Signature algorithm extension was skipped when renegotiation was in
progress, causing the signature algorithm not to be known when
renegotiating, and failing the handshake. Fix removes the renegotiation
step check before parsing the extension.
2017-10-11 12:49:00 +01:00
Hanno Becker
90333dab85 Replace wrong usage of WANT_READ by CONTINUE_PROCESSING 2017-10-10 16:04:48 +01:00
Hanno Becker
4cb1f4d49c Style corrections 2017-10-10 16:04:48 +01:00
Hanno Becker
ab74056037 Make use of mbedtls_dhm_set_group when generating DHM params 2017-10-04 13:17:52 +01:00
Andres Amaya Garcia
46f5a3e9b4 Check return codes from MD in ssl code 2017-07-20 16:17:51 +01:00
Andres Amaya Garcia
d21d625e1f Change ssl_srv to new MD API and check return code 2017-06-28 13:09:05 +01:00
Hanno Becker
83c9f495ff Prevent bounds check bypass through overflow in PSK identity parsing
The check `if( *p + n > end )` in `ssl_parse_client_psk_identity` is
unsafe because `*p + n` might overflow, thus bypassing the check. As
`n` is a user-specified value up to 65K, this is relevant if the
library happens to be located in the last 65K of virtual memory.

This commit replaces the check by a safe version.
2017-06-26 14:09:55 +01:00
Manuel Pégourié-Gonnard
ddc6e52cc1 Merge remote-tracking branch 'gilles/iotssl-1223/development' into development
* gilles/iotssl-1223/development:
  Fix FALLBACK_SCSV parsing
2017-06-06 20:11:36 +02:00
Manuel Pégourié-Gonnard
383a118338 Merge remote-tracking branch 'gilles/IOTSSL-1330/development' into development
* gilles/IOTSSL-1330/development:
  Changelog entry for the bug fixes
  SSLv3: when refusing renegotiation, stop processing
  Ignore failures when sending fatal alerts
  Cleaned up double variable declaration
  Code portability fix
  Added changelog entry
  Send TLS alerts in many more cases
  Skip all non-executables in run-test-suites.pl
  SSL tests: server requires auth, client has no certificate
  Balanced braces across preprocessor conditionals
  Support setting the ports on the command line
2017-06-06 19:22:41 +02:00
Manuel Pégourié-Gonnard
23b33f8663 Merge remote-tracking branch 'hanno/sig_hash_compatibility' into development
* hanno/sig_hash_compatibility:
  Improve documentation
  Split long lines
  Remember suitable hash function for any signature algorithm.
  Introduce macros and functions to characterize certain ciphersuites.
2017-06-06 18:14:57 +02:00
Gilles Peskine
d50177fdf3 Fix FALLBACK_SCSV parsing
Fixed a bug in ssl_srv.c when parsing TLS_FALLBACK_SCSV in the
ciphersuite list that caused it to miss it sometimes. Reported by Hugo
Leisink as issue #810. Fix initially by @andreasag01; this commit
isolates the bug fix and adds a non-regression test.
2017-05-16 17:53:03 +02:00