From fb236739da03bc6c0673e6a87a210fd7d055623e Mon Sep 17 00:00:00 2001 From: Jaeden Amero Date: Fri, 8 Feb 2019 13:11:59 +0000 Subject: [PATCH] Revert "Forbid passing NULL input buffers to RSA encryption routines" Resolve incompatibilties in the RSA module where changes made for parameter validation prevent Mbed Crypto from working. Mbed Crypto depends on being able to pass zero-length buffers that are NULL to RSA encryption functions. This reverts commit 2f660d047dd60ac68ebe6c8d4da0d141403b6d71. --- include/mbedtls/rsa.h | 9 ++++++--- library/rsa.c | 6 +++--- 2 files changed, 9 insertions(+), 6 deletions(-) diff --git a/include/mbedtls/rsa.h b/include/mbedtls/rsa.h index 4ff5bdd83..489f2ed45 100644 --- a/include/mbedtls/rsa.h +++ b/include/mbedtls/rsa.h @@ -601,7 +601,8 @@ int mbedtls_rsa_private( mbedtls_rsa_context *ctx, * #MBEDTLS_RSA_PUBLIC or #MBEDTLS_RSA_PRIVATE (deprecated). * \param ilen The length of the plaintext in Bytes. * \param input The input data to encrypt. This must be a readable - * buffer of size \p ilen Bytes. This must not be \c NULL. + * buffer of size \p ilen Bytes. It may be \c NULL if + * `ilen == 0`. * \param output The output buffer. This must be a writable buffer * of length \c ctx->len Bytes. For example, \c 256 Bytes * for an 2048-bit RSA modulus. @@ -641,7 +642,8 @@ int mbedtls_rsa_pkcs1_encrypt( mbedtls_rsa_context *ctx, * #MBEDTLS_RSA_PUBLIC or #MBEDTLS_RSA_PRIVATE (deprecated). * \param ilen The length of the plaintext in Bytes. * \param input The input data to encrypt. This must be a readable - * buffer of size \p ilen Bytes. This must not be \c NULL. + * buffer of size \p ilen Bytes. It may be \c NULL if + * `ilen == 0`. * \param output The output buffer. This must be a writable buffer * of length \c ctx->len Bytes. For example, \c 256 Bytes * for an 2048-bit RSA modulus. @@ -685,7 +687,8 @@ int mbedtls_rsa_rsaes_pkcs1_v15_encrypt( mbedtls_rsa_context *ctx, * \param label_len The length of the label in Bytes. * \param ilen The length of the plaintext buffer \p input in Bytes. * \param input The input data to encrypt. This must be a readable - * buffer of size \p ilen Bytes. This must not be \c NULL. + * buffer of size \p ilen Bytes. It may be \c NULL if + * `ilen == 0`. * \param output The output buffer. This must be a writable buffer * of length \c ctx->len Bytes. For example, \c 256 Bytes * for an 2048-bit RSA modulus. diff --git a/library/rsa.c b/library/rsa.c index af1a87859..389d7473e 100644 --- a/library/rsa.c +++ b/library/rsa.c @@ -1135,7 +1135,7 @@ int mbedtls_rsa_rsaes_oaep_encrypt( mbedtls_rsa_context *ctx, RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE || mode == MBEDTLS_RSA_PUBLIC ); RSA_VALIDATE_RET( output != NULL ); - RSA_VALIDATE_RET( input != NULL ); + RSA_VALIDATE_RET( ilen == 0 || input != NULL ); RSA_VALIDATE_RET( label_len == 0 || label != NULL ); if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 ) @@ -1218,7 +1218,7 @@ int mbedtls_rsa_rsaes_pkcs1_v15_encrypt( mbedtls_rsa_context *ctx, RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE || mode == MBEDTLS_RSA_PUBLIC ); RSA_VALIDATE_RET( output != NULL ); - RSA_VALIDATE_RET( input != NULL ); + RSA_VALIDATE_RET( ilen == 0 || input != NULL ); if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 ) return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA ); @@ -1285,7 +1285,7 @@ int mbedtls_rsa_pkcs1_encrypt( mbedtls_rsa_context *ctx, RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE || mode == MBEDTLS_RSA_PUBLIC ); RSA_VALIDATE_RET( output != NULL ); - RSA_VALIDATE_RET( input != NULL ); + RSA_VALIDATE_RET( ilen == 0 || input != NULL ); switch( ctx->padding ) {