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author | Jo-Philipp Wich <jow@openwrt.org> | 2015-05-04 08:49:21 +0000 |
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committer | Jo-Philipp Wich <jow@openwrt.org> | 2015-05-04 08:49:21 +0000 |
commit | 2569721374c2b0742611e428dacdc185485e38ab (patch) | |
tree | 1368012886ac55459ac8b49fe203a62ee350e033 /package/network/services/openvpn/patches | |
parent | 079ab1e22ae16a739bc87caa8d284a671f109959 (diff) | |
download | master-187ad058-2569721374c2b0742611e428dacdc185485e38ab.tar.gz master-187ad058-2569721374c2b0742611e428dacdc185485e38ab.tar.bz2 master-187ad058-2569721374c2b0742611e428dacdc185485e38ab.zip |
openvpn: disable CBC record splitting in PolarSSL/mbedTLS (#19101)
OpenVPN assumes that its control channel messages are sent and received
unfragmented, this assumption is broken when CBC record splitting is
enabled in mbedTLS.
The record splitting is intended as countermeasure against BEAST attacks
which do not apply to OpenVPN, therefore we simply disable it until
upstream OpenVPN gains the ability to process fragmented control
messages.
Disabling the splitting also works around a (not remotely triggerable)
segmentation fault in mbedTLS.
References:
* https://dev.openwrt.org/ticket/19101
* https://community.openvpn.net/openvpn/ticket/524
* https://github.com/ARMmbed/mbedtls/pull/185
Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@45602 3c298f89-4303-0410-b956-a3cf2f4a3e73
Diffstat (limited to 'package/network/services/openvpn/patches')
-rw-r--r-- | package/network/services/openvpn/patches/120-polarssl-disable-record-splitting.patch | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/package/network/services/openvpn/patches/120-polarssl-disable-record-splitting.patch b/package/network/services/openvpn/patches/120-polarssl-disable-record-splitting.patch new file mode 100644 index 0000000000..9e1511b6b6 --- /dev/null +++ b/package/network/services/openvpn/patches/120-polarssl-disable-record-splitting.patch @@ -0,0 +1,16 @@ +Index: openvpn-2.3.6/src/openvpn/ssl_polarssl.c +=================================================================== +--- openvpn-2.3.6.orig/src/openvpn/ssl_polarssl.c ++++ openvpn-2.3.6/src/openvpn/ssl_polarssl.c +@@ -707,6 +707,11 @@ void key_state_ssl_init(struct key_state + if (ssl_ctx->allowed_ciphers) + ssl_set_ciphersuites (ks_ssl->ctx, ssl_ctx->allowed_ciphers); + ++ /* Disable record splitting (breaks current ssl handling) */ ++#if defined(POLARSSL_SSL_CBC_RECORD_SPLITTING) ++ ssl_set_cbc_record_splitting (ks_ssl->ctx, SSL_CBC_RECORD_SPLITTING_DISABLED); ++#endif /* POLARSSL_SSL_CBC_RECORD_SPLITTING */ ++ + /* Initialise authentication information */ + if (is_server) + ssl_set_dh_param_ctx (ks_ssl->ctx, ssl_ctx->dhm_ctx ); |