Commit bd363985 authored by Manuel Pégourié-Gonnard's avatar Manuel Pégourié-Gonnard

Merge branch 'iotssl-519-asn1write-overflows-restricted' into development-restricted

* iotssl-519-asn1write-overflows-restricted:
  Fix other int casts in bounds checking
  Fix other occurrences of same bounds check issue
  Fix potential buffer overflow in asn1write
parents 537e2a9b bc5e5088
......@@ -9,6 +9,10 @@ Security
* Fix potential heap corruption on Windows when
mbedtls_x509_crt_parse_path() is passed a path longer than 2GB. Cannot be
triggered remotely. Found by Guido Vranken, Interlworks.
* Fix potential buffer overflow in some asn1_write_xxx() functions.
Cannot be triggered remotely unless you create X.509 certificates based
on untrusted input or write keys of untrusted origin. Found by Guido
Vranken, Interlworks.
* The X509 max_pathlen constraint was not enforced on intermediate
certificates. Found by Nicholas Wilson, fix and tests provided by
Janos Follath. #280 and #319
......
......@@ -87,7 +87,7 @@ int mbedtls_asn1_write_raw_buffer( unsigned char **p, unsigned char *start,
{
size_t len = 0;
if( *p - start < (int) size )
if( *p < start || (size_t)( *p - start ) < size )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
len = size;
......@@ -107,7 +107,7 @@ int mbedtls_asn1_write_mpi( unsigned char **p, unsigned char *start, const mbedt
//
len = mbedtls_mpi_size( X );
if( *p - start < (int) len )
if( *p < start || (size_t)( *p - start ) < len )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
(*p) -= len;
......@@ -270,7 +270,7 @@ int mbedtls_asn1_write_bitstring( unsigned char **p, unsigned char *start,
// Calculate byte length
//
if( *p - start < (int) size + 1 )
if( *p < start || (size_t)( *p - start ) < size + 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
len = size + 1;
......
......@@ -96,7 +96,7 @@ static int pk_write_ec_pubkey( unsigned char **p, unsigned char *start,
return( ret );
}
if( *p - start < (int) len )
if( *p < start || (size_t)( *p - start ) < len )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*p -= len;
......
......@@ -1105,11 +1105,16 @@ int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exch
#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
if( key_ex == MBEDTLS_KEY_EXCHANGE_PSK )
{
if( end - p < 2 + (int) psk_len )
if( end - p < 2 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
*(p++) = (unsigned char)( psk_len >> 8 );
*(p++) = (unsigned char)( psk_len );
if( end < p || (size_t)( end - p ) < psk_len )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
memset( p, 0, psk_len );
p += psk_len;
}
else
......@@ -1177,11 +1182,15 @@ int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exch
}
/* opaque psk<0..2^16-1>; */
if( end - p < 2 + (int) psk_len )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( end - p < 2 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
*(p++) = (unsigned char)( psk_len >> 8 );
*(p++) = (unsigned char)( psk_len );
if( end < p || (size_t)( end - p ) < psk_len )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
memcpy( p, psk, psk_len );
p += psk_len;
......
......@@ -259,13 +259,16 @@ int mbedtls_x509_write_sig( unsigned char **p, unsigned char *start,
int ret;
size_t len = 0;
if( *p - start < (int) size + 1 )
if( *p < start || (size_t)( *p - start ) < size )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
len = size;
(*p) -= len;
memcpy( *p, sig, len );
if( *p - start < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = 0;
len += 1;
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment