Merge server-side enforced renegotiation requests

This commit is contained in:
Paul Bakker 2014-07-04 15:01:37 +02:00
commit b9e08b086b
5 changed files with 132 additions and 5 deletions

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@ -20,6 +20,8 @@ Features
* Optimize for RAM usage in example config.h for NSA Suite B profile.
* Add POLARSSL_REMOVE_ARC4_CIPHERSUITES to allow removing RC4 ciphersuites
from the default list (inactive by default).
* Add server-side enforcement of sent renegotiation requests
(ssl_set_renegotiation_enforced())
Changes
* Add LINK_WITH_PTHREAD option in CMake for explicit linking that is

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@ -221,6 +221,9 @@
#define SSL_RENEGOTIATION_DISABLED 0
#define SSL_RENEGOTIATION_ENABLED 1
#define SSL_RENEGOTIATION_NOT_ENFORCED -1
#define SSL_RENEGO_MAX_RECORDS_DEFAULT 16
#define SSL_LEGACY_NO_RENEGOTIATION 0
#define SSL_LEGACY_ALLOW_RENEGOTIATION 1
#define SSL_LEGACY_BREAK_HANDSHAKE 2
@ -620,6 +623,7 @@ struct _ssl_context
*/
int state; /*!< SSL handshake: current state */
int renegotiation; /*!< Initial or renegotiation */
int renego_records_seen; /*!< Records since renego request */
int major_ver; /*!< equal to SSL_MAJOR_VERSION_3 */
int minor_ver; /*!< either 0 (SSL3) or 1 (TLS1.0) */
@ -744,6 +748,7 @@ struct _ssl_context
int verify_result; /*!< verification result */
int disable_renegotiation; /*!< enable/disable renegotiation */
int allow_legacy_renegotiation; /*!< allow legacy renegotiation */
int renego_max_records; /*!< grace period for renegotiation */
const int *ciphersuite_list[4]; /*!< allowed ciphersuites / version */
#if defined(POLARSSL_SSL_SET_CURVES)
const ecp_group_id *curve_list; /*!< allowed curves */
@ -1421,6 +1426,33 @@ void ssl_set_renegotiation( ssl_context *ssl, int renegotiation );
*/
void ssl_legacy_renegotiation( ssl_context *ssl, int allow_legacy );
/**
* \brief Enforce server-requested renegotiation.
* (Default: enforced, max_records = 16)
* (No effect on client.)
*
* When a server requests a renegotiation, the client can
* comply or ignore the request. This function allows the
* server to decide if it should enforce its renegotiation
* requests by closing the connection if the client doesn't
* initiate a renegotiation.
*
* However, records could already be in transit from the
* client to the server when the request is emitted. In order
* to increase reliability, the server can accept a number of
* records containing application data before the ClientHello
* that was requested.
*
* The optimal value is highly dependent on the specific usage
* scenario.
*
* \param ssl SSL context
* \param max_records Use SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to
* enforce renegotiation, or a non-negative value to enforce
* it but allow for a grace period of max_records records.
*/
void ssl_set_renegotiation_enforced( ssl_context *ssl, int max_records );
/**
* \brief Return the number of data bytes available to read
*

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@ -3055,7 +3055,10 @@ void ssl_handshake_wrapup( ssl_context *ssl )
ssl->handshake = NULL;
if( ssl->renegotiation == SSL_RENEGOTIATION )
{
ssl->renegotiation = SSL_RENEGOTIATION_DONE;
ssl->renego_records_seen = 0;
}
/*
* Switch in our now active transform context
@ -3345,6 +3348,8 @@ int ssl_init( ssl_context *ssl )
ssl_set_ciphersuites( ssl, ssl_list_ciphersuites() );
ssl->renego_max_records = SSL_RENEGO_MAX_RECORDS_DEFAULT;
#if defined(POLARSSL_DHM_C)
if( ( ret = mpi_read_string( &ssl->dhm_P, 16,
POLARSSL_DHM_RFC5114_MODP_1024_P) ) != 0 ||
@ -3435,6 +3440,8 @@ int ssl_session_reset( ssl_context *ssl )
ssl->transform_in = NULL;
ssl->transform_out = NULL;
ssl->renego_records_seen = 0;
memset( ssl->out_ctr, 0, SSL_BUFFER_LEN );
memset( ssl->in_ctr, 0, SSL_BUFFER_LEN );
@ -3952,6 +3959,11 @@ void ssl_legacy_renegotiation( ssl_context *ssl, int allow_legacy )
ssl->allow_legacy_renegotiation = allow_legacy;
}
void ssl_set_renegotiation_enforced( ssl_context *ssl, int max_records )
{
ssl->renego_max_records = max_records;
}
#if defined(POLARSSL_SSL_SESSION_TICKETS)
int ssl_set_session_tickets( ssl_context *ssl, int use_tickets )
{
@ -4296,9 +4308,15 @@ int ssl_read( ssl_context *ssl, unsigned char *buf, size_t len )
}
else if( ssl->renegotiation == SSL_RENEGOTIATION_PENDING )
{
SSL_DEBUG_MSG( 1, ( "renegotiation requested, "
"but not honored by client" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
ssl->renego_records_seen++;
if( ssl->renego_max_records >= 0 &&
ssl->renego_records_seen > ssl->renego_max_records )
{
SSL_DEBUG_MSG( 1, ( "renegotiation requested, "
"but not honored by client" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
}
else if( ssl->in_msgtype != SSL_MSG_APPLICATION_DATA )
{

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@ -99,6 +99,7 @@ int main( int argc, char *argv[] )
#define DFL_RENEGOTIATION SSL_RENEGOTIATION_DISABLED
#define DFL_ALLOW_LEGACY SSL_LEGACY_NO_RENEGOTIATION
#define DFL_RENEGOTIATE 0
#define DFL_RENEGO_DELAY -2
#define DFL_MIN_VERSION -1
#define DFL_MAX_VERSION -1
#define DFL_AUTH_MODE SSL_VERIFY_OPTIONAL
@ -159,6 +160,7 @@ struct options
int renegotiation; /* enable / disable renegotiation */
int allow_legacy; /* allow legacy renegotiation */
int renegotiate; /* attempt renegotiation? */
int renego_delay; /* delay before enforcing renegotiation */
int min_version; /* minimum protocol version accepted */
int max_version; /* maximum protocol version accepted */
int auth_mode; /* verify mode for connection */
@ -676,6 +678,7 @@ int main( int argc, char *argv[] )
opt.renegotiation = DFL_RENEGOTIATION;
opt.allow_legacy = DFL_ALLOW_LEGACY;
opt.renegotiate = DFL_RENEGOTIATE;
opt.renego_delay = DFL_RENEGO_DELAY;
opt.min_version = DFL_MIN_VERSION;
opt.max_version = DFL_MAX_VERSION;
opt.auth_mode = DFL_AUTH_MODE;
@ -765,6 +768,10 @@ int main( int argc, char *argv[] )
if( opt.renegotiate < 0 || opt.renegotiate > 1 )
goto usage;
}
else if( strcmp( p, "renego_delay" ) == 0 )
{
opt.renego_delay = atoi( q );
}
else if( strcmp( p, "min_version" ) == 0 )
{
if( strcmp( q, "ssl3" ) == 0 )
@ -1264,6 +1271,8 @@ int main( int argc, char *argv[] )
ssl_set_renegotiation( &ssl, opt.renegotiation );
ssl_legacy_renegotiation( &ssl, opt.allow_legacy );
if( opt.renego_delay != DFL_RENEGO_DELAY )
ssl_set_renegotiation_enforced( &ssl, opt.renego_delay );
#if defined(POLARSSL_X509_CRT_PARSE_C)
if( strcmp( opt.ca_path, "none" ) != 0 &&

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@ -616,9 +616,11 @@ run_test "Renegotiation #4 (client-initiated, server-rejected)" \
-c "found renegotiation extension" \
-c "=> renegotiate" \
-S "=> renegotiate" \
-S "write hello request"
-S "write hello request" \
-c "SSL - An unexpected message was received from our peer" \
-c "failed"
run_test "Renegotiation #5 (server-initiated, client-rejected)" \
run_test "Renegotiation #5 (server-initiated, client-rejected, default)" \
"$P_SRV debug_level=4 renegotiation=1 renegotiate=1" \
"$P_CLI debug_level=4 renegotiation=0" \
0 \
@ -630,9 +632,73 @@ run_test "Renegotiation #5 (server-initiated, client-rejected)" \
-C "=> renegotiate" \
-S "=> renegotiate" \
-s "write hello request" \
-S "SSL - An unexpected message was received from our peer" \
-S "failed"
run_test "Renegotiation #6 (server-initiated, client-rejected, not enforced)" \
"$P_SRV debug_level=4 renegotiation=1 renegotiate=1 \
renego_delay=-1" \
"$P_CLI debug_level=4 renegotiation=0" \
0 \
-C "client hello, adding renegotiation extension" \
-s "received TLS_EMPTY_RENEGOTIATION_INFO" \
-S "found renegotiation extension" \
-s "server hello, secure renegotiation extension" \
-c "found renegotiation extension" \
-C "=> renegotiate" \
-S "=> renegotiate" \
-s "write hello request" \
-S "SSL - An unexpected message was received from our peer" \
-S "failed"
run_test "Renegotiation #7 (server-initiated, client-rejected, delay 1)" \
"$P_SRV debug_level=4 renegotiation=1 renegotiate=1 \
renego_delay=1" \
"$P_CLI debug_level=4 renegotiation=0" \
0 \
-C "client hello, adding renegotiation extension" \
-s "received TLS_EMPTY_RENEGOTIATION_INFO" \
-S "found renegotiation extension" \
-s "server hello, secure renegotiation extension" \
-c "found renegotiation extension" \
-C "=> renegotiate" \
-S "=> renegotiate" \
-s "write hello request" \
-S "SSL - An unexpected message was received from our peer" \
-S "failed"
run_test "Renegotiation #8 (server-initiated, client-rejected, delay 0)" \
"$P_SRV debug_level=4 renegotiation=1 renegotiate=1 \
renego_delay=0" \
"$P_CLI debug_level=4 renegotiation=0" \
0 \
-C "client hello, adding renegotiation extension" \
-s "received TLS_EMPTY_RENEGOTIATION_INFO" \
-S "found renegotiation extension" \
-s "server hello, secure renegotiation extension" \
-c "found renegotiation extension" \
-C "=> renegotiate" \
-S "=> renegotiate" \
-s "write hello request" \
-s "SSL - An unexpected message was received from our peer" \
-s "failed"
run_test "Renegotiation #9 (server-initiated, client-accepted, delay 0)" \
"$P_SRV debug_level=4 renegotiation=1 renegotiate=1 \
renego_delay=0" \
"$P_CLI debug_level=4 renegotiation=1" \
0 \
-c "client hello, adding renegotiation extension" \
-s "received TLS_EMPTY_RENEGOTIATION_INFO" \
-s "found renegotiation extension" \
-s "server hello, secure renegotiation extension" \
-c "found renegotiation extension" \
-c "=> renegotiate" \
-s "=> renegotiate" \
-s "write hello request" \
-S "SSL - An unexpected message was received from our peer" \
-S "failed"
# Tests for auth_mode
run_test "Authentication #1 (server badcert, client required)" \