diff --git a/src/common/sha2/sha2.c b/src/common/sha2/sha2.c
index 47788c7e7..b34e61273 100644
--- a/src/common/sha2/sha2.c
+++ b/src/common/sha2/sha2.c
@@ -7,121 +7,82 @@
 static struct OQS_SHA2_callbacks *callbacks = &sha2_default_callbacks;
 
 OQS_API void OQS_SHA2_set_callbacks(struct OQS_SHA2_callbacks *new_callbacks) {
-	if (new_callbacks != NULL) {
-		callbacks = new_callbacks;
-	}
+	callbacks = new_callbacks;
 }
 
 void OQS_SHA2_sha256_inc_init(OQS_SHA2_sha256_ctx *state) {
-	if (state != NULL && callbacks != NULL && callbacks->SHA2_sha256_inc_init != NULL) {
-		callbacks->SHA2_sha256_inc_init(state);
-	}
+	callbacks->SHA2_sha256_inc_init(state);
 }
 
 void OQS_SHA2_sha256_inc_ctx_clone(OQS_SHA2_sha256_ctx *dest, const OQS_SHA2_sha256_ctx *src) {
-	if (dest != NULL && src != NULL && callbacks != NULL && callbacks->SHA2_sha256_inc_ctx_clone != NULL) {
-		callbacks->SHA2_sha256_inc_ctx_clone(dest, src);
-	}
+	callbacks->SHA2_sha256_inc_ctx_clone(dest, src);
 }
 
 void OQS_SHA2_sha256_inc_blocks(OQS_SHA2_sha256_ctx *state, const uint8_t *in, size_t inblocks) {
-	if (state != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha256_inc_blocks != NULL) {
-		callbacks->SHA2_sha256_inc_blocks(state, in, inblocks);
-	}
+	callbacks->SHA2_sha256_inc_blocks(state, in, inblocks);
 }
 
 void OQS_SHA2_sha256_inc(OQS_SHA2_sha256_ctx *state, const uint8_t *in, size_t len) {
-	if (state != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha256_inc != NULL) {
-		callbacks->SHA2_sha256_inc(state, in, len);
-	}
+	callbacks->SHA2_sha256_inc(state, in, len);
 }
 
 void OQS_SHA2_sha256_inc_finalize(uint8_t *out, OQS_SHA2_sha256_ctx *state, const uint8_t *in, size_t inlen) {
-	if (out != NULL && state != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha256_inc_finalize != NULL) {
-		callbacks->SHA2_sha256_inc_finalize(out, state, in, inlen);
-	}
+	callbacks->SHA2_sha256_inc_finalize(out, state, in, inlen);
 }
 
 void OQS_SHA2_sha256_inc_ctx_release(OQS_SHA2_sha256_ctx *state) {
-	if (state != NULL && callbacks != NULL && callbacks->SHA2_sha256_inc_ctx_release != NULL) {
-		callbacks->SHA2_sha256_inc_ctx_release(state);
-	}
+	callbacks->SHA2_sha256_inc_ctx_release(state);
 }
 
 void OQS_SHA2_sha384_inc_init(OQS_SHA2_sha384_ctx *state) {
-	if (state != NULL && callbacks != NULL && callbacks->SHA2_sha384_inc_init != NULL) {
-		callbacks->SHA2_sha384_inc_init(state);
-	}
+	callbacks->SHA2_sha384_inc_init(state);
 }
 
 void OQS_SHA2_sha384_inc_ctx_clone(OQS_SHA2_sha384_ctx *dest, const OQS_SHA2_sha384_ctx *src) {
-	if (dest != NULL && src != NULL && callbacks != NULL && callbacks->SHA2_sha384_inc_ctx_clone != NULL) {
-		callbacks->SHA2_sha384_inc_ctx_clone(dest, src);
-	}
+	callbacks->SHA2_sha384_inc_ctx_clone(dest, src);
 }
 
 void OQS_SHA2_sha384_inc_blocks(OQS_SHA2_sha384_ctx *state, const uint8_t *in, size_t inblocks) {
-	if (state != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha384_inc_blocks != NULL) {
-		callbacks->SHA2_sha384_inc_blocks(state, in, inblocks);
-	}
+	callbacks->SHA2_sha384_inc_blocks(state, in, inblocks);
 }
 
 void OQS_SHA2_sha384_inc_finalize(uint8_t *out, OQS_SHA2_sha384_ctx *state, const uint8_t *in, size_t inlen) {
-	if (out != NULL && state != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha384_inc_finalize != NULL) {
-		callbacks->SHA2_sha384_inc_finalize(out, state, in, inlen);
-	}
+	callbacks->SHA2_sha384_inc_finalize(out, state, in, inlen);
 }
 
 void OQS_SHA2_sha384_inc_ctx_release(OQS_SHA2_sha384_ctx *state) {
-	if (state != NULL && callbacks != NULL && callbacks->SHA2_sha384_inc_ctx_release != NULL) {
-		callbacks->SHA2_sha384_inc_ctx_release(state);
-	}
+	callbacks->SHA2_sha384_inc_ctx_release(state);
 }
 
 void OQS_SHA2_sha512_inc_init(OQS_SHA2_sha512_ctx *state) {
-	if (state != NULL && callbacks != NULL && callbacks->SHA2_sha512_inc_init != NULL) {
-		callbacks->SHA2_sha512_inc_init(state);
-	}
+	callbacks->SHA2_sha512_inc_init(state);
 }
 
 void OQS_SHA2_sha512_inc_ctx_clone(OQS_SHA2_sha512_ctx *dest, const OQS_SHA2_sha512_ctx *src) {
-	if (dest != NULL && src != NULL && callbacks != NULL && callbacks->SHA2_sha512_inc_ctx_clone != NULL) {
-		callbacks->SHA2_sha512_inc_ctx_clone(dest, src);
-	}
+	callbacks->SHA2_sha512_inc_ctx_clone(dest, src);
 }
 
 void OQS_SHA2_sha512_inc_blocks(OQS_SHA2_sha512_ctx *state, const uint8_t *in, size_t inblocks) {
-	if (state != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha512_inc_blocks != NULL) {
-		callbacks->SHA2_sha512_inc_blocks(state, in, inblocks);
-	}
+	callbacks->SHA2_sha512_inc_blocks(state, in, inblocks);
 }
 
 void OQS_SHA2_sha512_inc_finalize(uint8_t *out, OQS_SHA2_sha512_ctx *state, const uint8_t *in, size_t inlen) {
-	if (out != NULL && state != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha512_inc_finalize != NULL) {
-		callbacks->SHA2_sha512_inc_finalize(out, state, in, inlen);
-	}
+	callbacks->SHA2_sha512_inc_finalize(out, state, in, inlen);
 }
 
 void OQS_SHA2_sha512_inc_ctx_release(OQS_SHA2_sha512_ctx *state) {
-	if (state != NULL && callbacks != NULL && callbacks->SHA2_sha512_inc_ctx_release != NULL) {
-		callbacks->SHA2_sha512_inc_ctx_release(state);
-	}
+	callbacks->SHA2_sha512_inc_ctx_release(state);
 }
 
 void OQS_SHA2_sha256(uint8_t *out, const uint8_t *in, size_t inlen) {
-	if (out != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha256 != NULL) {
-		callbacks->SHA2_sha256(out, in, inlen);
-	}
+	callbacks->SHA2_sha256(out, in, inlen);
 }
 
 void OQS_SHA2_sha384(uint8_t *out, const uint8_t *in, size_t inlen) {
-	if (out != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha384 != NULL) {
-		callbacks->SHA2_sha384(out, in, inlen);
-	}
+	callbacks->SHA2_sha384(out, in, inlen);
 }
 
 void OQS_SHA2_sha512(uint8_t *out, const uint8_t *in, size_t inlen) {
-	if (out != NULL && in != NULL && callbacks != NULL && callbacks->SHA2_sha512 != NULL) {
-		callbacks->SHA2_sha512(out, in, inlen);
-	}
+	callbacks->SHA2_sha512(out, in, inlen);
 }
+