diff --git a/library/pk.c b/library/pk.c
index 5dd0fa8..6a3c860 100644
--- a/library/pk.c
+++ b/library/pk.c
@@ -57,7 +57,6 @@
  */
 void mbedtls_pk_init( mbedtls_pk_context *ctx )
 {
-    PK_VALIDATE( ctx != NULL );
 
     ctx->pk_info = NULL;
     ctx->pk_ctx = NULL;
@@ -83,7 +82,6 @@
  */
 void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx )
 {
-    PK_VALIDATE( ctx != NULL );
     ctx->pk_info = NULL;
     ctx->rs_ctx = NULL;
 }
@@ -137,7 +135,6 @@
  */
 int mbedtls_pk_setup( mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info )
 {
-    PK_VALIDATE_RET( ctx != NULL );
     if( info == NULL || ctx->pk_info != NULL )
         return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
 
@@ -200,7 +197,6 @@
     mbedtls_rsa_alt_context *rsa_alt;
     const mbedtls_pk_info_t *info = &mbedtls_rsa_alt_info;
 
-    PK_VALIDATE_RET( ctx != NULL );
     if( ctx->pk_info != NULL )
         return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
 
@@ -404,10 +400,8 @@
                const unsigned char *sig, size_t sig_len,
                mbedtls_pk_restart_ctx *rs_ctx )
 {
-    PK_VALIDATE_RET( ctx != NULL );
     PK_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE && hash_len == 0 ) ||
                      hash != NULL );
-    PK_VALIDATE_RET( sig != NULL );
 
     if( ctx->pk_info == NULL ||
         pk_hashlen_helper( md_alg, &hash_len ) != 0 )
@@ -462,10 +456,8 @@
                    const unsigned char *hash, size_t hash_len,
                    const unsigned char *sig, size_t sig_len )
 {
-    PK_VALIDATE_RET( ctx != NULL );
     PK_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE && hash_len == 0 ) ||
                      hash != NULL );
-    PK_VALIDATE_RET( sig != NULL );
 
     if( ctx->pk_info == NULL )
         return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
@@ -588,10 +580,8 @@
              int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
              mbedtls_pk_restart_ctx *rs_ctx )
 {
-    PK_VALIDATE_RET( ctx != NULL );
     PK_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE && hash_len == 0 ) ||
                      hash != NULL );
-    PK_VALIDATE_RET( sig != NULL );
 
     if( ctx->pk_info == NULL ||
         pk_hashlen_helper( md_alg, &hash_len ) != 0 )
@@ -707,10 +697,6 @@
                 unsigned char *output, size_t *olen, size_t osize,
                 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
 {
-    PK_VALIDATE_RET( ctx != NULL );
-    PK_VALIDATE_RET( input != NULL || ilen == 0 );
-    PK_VALIDATE_RET( output != NULL || osize == 0 );
-    PK_VALIDATE_RET( olen != NULL );
 
     if( ctx->pk_info == NULL )
         return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
@@ -730,10 +716,6 @@
                 unsigned char *output, size_t *olen, size_t osize,
                 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
 {
-    PK_VALIDATE_RET( ctx != NULL );
-    PK_VALIDATE_RET( input != NULL || ilen == 0 );
-    PK_VALIDATE_RET( output != NULL || osize == 0 );
-    PK_VALIDATE_RET( olen != NULL );
 
     if( ctx->pk_info == NULL )
         return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
@@ -753,8 +735,6 @@
                            int (*f_rng)(void *, unsigned char *, size_t),
                            void *p_rng )
 {
-    PK_VALIDATE_RET( pub != NULL );
-    PK_VALIDATE_RET( prv != NULL );
 
     if( pub->pk_info == NULL ||
         prv->pk_info == NULL )
@@ -800,7 +780,6 @@
  */
 int mbedtls_pk_debug( const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items )
 {
-    PK_VALIDATE_RET( ctx != NULL );
     if( ctx->pk_info == NULL )
         return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );