Commit Graph

9934 Commits

Author SHA1 Message Date
Janos Follath
e5670f2663 Remove unnecessary cast from ECP test 2019-02-26 16:48:40 +00:00
Hanno Becker
775655eead Update programs/ssl/query_config.c 2019-02-26 14:38:40 +00:00
Hanno Becker
23699efe78 ssl_client2: Reset peer CRT info string on reconnect 2019-02-26 14:38:09 +00:00
Hanno Becker
bd5580abb1 Add further debug statements on assertion failures 2019-02-26 14:38:09 +00:00
Hanno Becker
353a6f0d50 Fix typo in documentation of ssl_parse_certificate_chain() 2019-02-26 14:38:09 +00:00
Hanno Becker
62d58ed975 Add debug output in case of assertion failure 2019-02-26 14:38:09 +00:00
Hanno Becker
6883874013 Fix typo in SSL ticket documentation 2019-02-26 14:38:09 +00:00
Hanno Becker
fe4ef0c1ae Add config sanity check for !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE 2019-02-26 14:38:09 +00:00
Hanno Becker
a1051b4e9a ssl_client2: Zeroize peer CRT info buffer when reconnecting 2019-02-26 14:38:09 +00:00
Hanno Becker
fe9aec4cb1 Reintroduce numerous ssl-opt.sh tests if !MBEDTLS_SSL_KEEP_PEER_CERT 2019-02-26 14:38:09 +00:00
Hanno Becker
a9766c2c23 ssl_client2: Extract peer CRT info from verification callback
So far, `ssl_client2` printed the CRT info for the peer's CRT
by requesting the latter through `mbedtls_ssl_get_peer_cert()`
at the end of the handshake, and printing it via
`mbedtls_x509_crt_info()`. When `MBEDTLS_SSL_KEEP_PEER_CERTIFICATE`
is disabled, this does no longer work because the peer's CRT
isn't stored beyond the handshake.

This makes some tests in `ssl-opt.sh` fail which rely on the CRT
info output for the peer certificate.

This commit modifies `ssl_client2` to extract the peer CRT info
from the verification callback, which is always called at a time
when the peer's CRT is available. This way, the peer's CRT info
is still printed if `MBEDTLS_SSL_KEEP_PEER_CERTIFICATE` is disabled.
2019-02-26 14:38:09 +00:00
Hanno Becker
958efeb481 Improve documentation of mbedtls_ssl_get_peer_cert() 2019-02-26 14:38:09 +00:00
Hanno Becker
fd7f298c6a Improve documentation of MBEDTLS_SSL_KEEP_PEER_CERTIFICATE 2019-02-26 14:38:09 +00:00
Hanno Becker
3fd3f5ebe4 Fix indentation of Doxygen comment in ssl_internal.h 2019-02-26 14:38:09 +00:00
Hanno Becker
accc5998ae Set peer CRT length only after successful allocation 2019-02-26 14:38:09 +00:00
Hanno Becker
3acc9b9042 Remove question in comment about verify flags on cli vs. server 2019-02-26 14:38:09 +00:00
Hanno Becker
1aed7779ec Remove misleading and redundant guard around restartable ECC field
`MBEDTLS_SSL__ECP_RESTARTABLE` is only defined if
`MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED` is set, which
requires `MBEDTLS_X509_PARSE_C` to be set (this is checked
in `check_config.`). The additional `MBEDTLS_X509_PARSE_C`
guard around the `ecrs_peer_cert` field is therefore not
necessary; moreover, it's misleading, because it hasn't
been used consistently throughout the code.
2019-02-26 14:38:09 +00:00
Hanno Becker
545ced45f7 Add test for !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE to all.sh 2019-02-26 14:38:09 +00:00
Hanno Becker
6b8fbab290 Free peer CRT chain immediately after verifying it
If we don't need to store the peer's CRT chain permanently, we may
free it immediately after verifying it. Moreover, since we parse the
CRT chain in-place from the input buffer in this case, pointers from
the CRT structure remain valid after freeing the structure, and we
use that to extract the digest and pubkey from the CRT after freeing
the structure.
2019-02-26 14:38:09 +00:00
Hanno Becker
0056eab3cd Parse peer's CRT chain in-place from the input buffer 2019-02-26 14:38:09 +00:00
Hanno Becker
ae553dde3a Free peer's public key as soon as it's no longer needed
On constrained devices, this saves a significant amount of RAM that
might be needed for subsequent expensive operations like ECDHE.
2019-02-26 14:38:09 +00:00
Hanno Becker
b9d4479080 Correct compile-time guards for ssl_clear_peer_cert()
It is used in `mbedtls_ssl_session_free()` under
`MBEDTLS_X509_CRT_PARSE_C`, but defined only if
`MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED`.

Issue #2422 tracks the use of
`MBEDTLS_KEY_EXCHANGE__WITH_CERT_ENABLED` instead of
`MBEDTLS_X509_CRT_PARSE_C` for code and fields
related to CRT-based ciphersuites.
2019-02-26 14:38:09 +00:00
Hanno Becker
e31505d64e Adapt ChangeLog 2019-02-26 14:38:09 +00:00
Hanno Becker
e68245750a Guard mbedtls_ssl_get_peer_cert() by new compile-time option 2019-02-26 14:38:09 +00:00
Hanno Becker
d0aac14303 Add dependency to ssl-opt.sh tests which need peer CRT debug info 2019-02-26 14:38:09 +00:00
Hanno Becker
b6c5eca2d5 Adapt mbedtls_ssl_parse_certificate() to removal of peer_cert field 2019-02-26 14:38:09 +00:00
Hanno Becker
13c327d500 Adapt ssl_clear_peer_cert() to removal of peer_cert field 2019-02-26 14:38:09 +00:00
Hanno Becker
6d1986e6f5 Adapt mbedtls_ssl_session_copy() to removal of peer_cert field 2019-02-26 14:38:09 +00:00
Hanno Becker
94cc26dfa6 Adapt session ticket implementation to removal of peer_cert field 2019-02-26 14:38:09 +00:00
Hanno Becker
abe6f66c00 Remove peer CRT from mbedtls_ssl_session if new option is disabled 2019-02-26 14:38:09 +00:00
Hanno Becker
2a831a4ba7 Adapt client auth detection in ssl_parse_certificate_verify()
The server expects a CertificateVerify message only if it has
previously received a Certificate from the client.

So far, this was detected by looking at the `peer_cert` field
in the current session. Preparing to remove the latter, this
commit changes this to instead determine the presence of a peer
certificate by checking the new `peer_cert_digest` pointer.
2019-02-26 14:38:09 +00:00
Hanno Becker
57b33c9e4e Use mbedtls_ssl_get_peer_cert() to query peer cert in cert_app 2019-02-26 14:38:09 +00:00
Hanno Becker
a1ab9be367 Adapt server-side signature verification to use raw public key
We must dispatch between the peer's public key stored as part of
the peer's CRT in the current session structure (situation until
now, and future behaviour if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is
enabled), and the sole public key stored in the handshake structure
(new, if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is disabled).
2019-02-26 14:38:09 +00:00
Hanno Becker
a6899bb89d Adapt client-side signature verification to use raw public key
We must dispatch between the peer's public key stored as part of
the peer's CRT in the current session structure (situation until
now, and future behaviour if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is
enabled), and the sole public key stored in the handshake structure
(new, if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is disabled).
2019-02-26 14:38:09 +00:00
Hanno Becker
be7f50866d Adapt ssl_get_ecdh_params_from_cert() to use raw public key
We must dispatch between the peer's public key stored as part of
the peer's CRT in the current session structure (situation until
now, and future behaviour if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is
enabled), and the sole public key stored in the handshake structure
(new, if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is disabled).
2019-02-26 14:38:09 +00:00
Hanno Becker
c7d7e29b46 Adapt ssl_write_encrypted_pms() to use raw public key
We must dispatch between the peer's public key stored as part of
the peer's CRT in the current session structure (situation until
now, and future behaviour if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is
enabled), and the sole public key stored in the handshake structure
(new, if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is disabled).
2019-02-26 14:38:09 +00:00
Hanno Becker
a27475335a Make a copy of peer's raw public key after verifying its CRT chain
This commit modifies `mbedtls_ssl_parse_certificate()` to store a
copy of the peer's public key after parsing and verifying the peer's
CRT chain.

So far, this leads to heavy memory duplication: We have the CRT chain
in the I/O buffer, then parse (and, thereby, copy) it to a
`mbedtls_x509_crt` structure, and then make another copy of the
peer's public key, plus the overhead from the MPI and ECP structures.

This inefficiency will soon go away to a significant extend, because:
- Another PR adds functionality to parse CRTs without taking
  ownership of the input buffers. Applying this here will allow
  parsing and verifying the peer's chain without making an additional
  raw copy. The overhead reduces to the size of `mbedtls_x509_crt`,
  the public key, and the DN structures referenced in the CRT.
- Once copyless parsing is in place and the removal of the peer CRT
  is fully implemented, we can extract the public key bounds from
  the parsed certificate and then free the entire chain before
  parsing the public key again. This means that we never store
  the parsed public key twice at the same time.
2019-02-26 14:38:09 +00:00
Hanno Becker
75173121fe Add field for peer's raw public key to TLS handshake param structure
When removing the (session-local) copy of the peer's CRT chain, we must
keep a handshake-local copy of the peer's public key, as (naturally) every
key exchange will make use of that public key at some point to verify that
the peer actually owns the corresponding private key (e.g., verify signatures
from ServerKeyExchange or CertificateVerify, or encrypt a PMS in a RSA-based
exchange, or extract static (EC)DH parameters).

This commit adds a PK context field `peer_pubkey` to the handshake parameter
structure `mbedtls_handshake_params_init()` and adapts the init and free
functions accordingly. It does not yet make actual use of the new field.
2019-02-26 14:38:09 +00:00
Hanno Becker
494dd7a6b4 Add raw public key buffer bounds to mbedtls_x509_crt struct
This commit adds an ASN.1 buffer field `pk_raw` to `mbedtls_x509_crt`
which stores the bounds of the raw public key data within an X.509 CRT.

This will be useful in subsequent commits to extract the peer's public
key from its certificate chain.
2019-02-26 14:38:09 +00:00
Hanno Becker
a887d1a5b6 Remove peer CRT from cache if !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE 2019-02-26 14:38:09 +00:00
Hanno Becker
c966bd16be Remove peer CRT from tickets if !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE 2019-02-26 14:38:09 +00:00
Hanno Becker
c5fcbb33c0 Add peer CRT digest to session tickets
This commit changes the format of session tickets to include
the digest of the peer's CRT if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE
is disabled.

This commit does not yet remove the peer CRT itself.
2019-02-26 14:38:09 +00:00
Hanno Becker
3dad311ef0 Parse and verify peer CRT chain in local variable
`mbedtls_ssl_parse_certificate()` parses the peer's certificate chain
directly into the `peer_cert` field of the `mbedtls_ssl_session`
structure being established. To allow to optionally remove this field
from the session structure, this commit changes this to parse the peer's
chain into a local variable instead first, which can then either be freed
after CRT verification - in case the chain should not be stored - or
mapped to the `peer_cert` if it should be kept. For now, only the latter
is implemented.
2019-02-26 14:38:09 +00:00
Hanno Becker
177475a3aa Mitigate triple handshake attack by comparing digests only
This paves the way for the removal of the peer CRT chain from
`mbedtls_ssl_session`.
2019-02-26 14:38:09 +00:00
Hanno Becker
6bbd94c4eb Compute digest of peer's end-CRT in mbedtls_ssl_parse_certificate() 2019-02-26 14:38:09 +00:00
Hanno Becker
9198ad1101 Extend mbedtls_ssl_session by buffer holding peer CRT digest 2019-02-26 14:38:09 +00:00
Hanno Becker
8d84fd83ff Update version_features.c 2019-02-26 14:38:09 +00:00
Hanno Becker
bb278f52ca Add configuration option to remove peer CRT after handshake 2019-02-26 14:38:09 +00:00
Hanno Becker
4a82c1ccb4 Improve documentation of mbedtls_ssl_get_peer_cert() 2019-02-26 14:38:09 +00:00
Hanno Becker
8273df8383 Re-classify errors on missing peer CRT
mbedtls_ssl_parse_certificate() will fail if a ciphersuite requires
a certificate, but none is provided. While it is sensible to double-
check this, failure should be reported as an internal error and not
as an unexpected message.
2019-02-26 14:38:09 +00:00