TeamHepta/mbedtls
1
0
Fork 0
mirror of https://github.com/Mbed-TLS/mbedtls.git synced 2026-05-11 06:28:17 +02:00
Code Issues Packages Projects Releases Wiki Activity

Don't store client-supported ECs in heap-allocated buffer

Browse Source 
So far, the client-proposed list of elliptic curves was stored for the
duration of the entire handshake in a heap-allocated buffer referenced
from mbedtls_ssl_handshake_params::curves. It is used in the following
places:
1) When the server chooses a suitable ciphersuite, it checks that
   it has a certificate matching the ciphersuite; in particular, if
   the ciphersuite involves ECDHE, the server needs an EC certificate
   with a curve suitable for the client.
2) When performing the ECDHE key exchange, the server choose one
   curve among those proposed by the client which matches the server's
   own supported curve configuration.

This commit removes the hold back the entire client-side curve list
during the handshake, by performing (1) and (2) on during ClientHello
parsing, and in case of (2) only remembering the curve chosen for ECDHE
within mbedtls_ssl_handshake_params.
This commit is contained in:
Hanno Becker
2019-06-17 14:30:05 +01:00
parent 1841f84c79
commit d3b2fcb7c6
3 changed files with 65 additions and 65 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
include/mbedtls/ssl_internal.h
View File

@@ -383,7 +383,7 @@ struct mbedtls_ssl_handshake_params
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
const mbedtls_ecp_curve_info **curves; /*!< Supported elliptic curves */
mbedtls_ecp_curve_info const *curve_info; /*!< Info for EC for ECDHE. */
#endif
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
unsigned char *psk; /*!< PSK from the callback */