diff --git a/include/openssl/bn.h b/include/openssl/bn.h
index 0a1f5e5..d85ec86 100644
--- a/include/openssl/bn.h
+++ b/include/openssl/bn.h
@@ -304,6 +304,11 @@
  * result to |ret|. It returns one on success and zero on failure. */
 OPENSSL_EXPORT int BN_cbs2unsigned(CBS *cbs, BIGNUM *ret);
 
+/* BN_cbs2unsigned_buggy acts like |BN_cbs2unsigned| but tolerates negative
+ * INTEGERs. This is to work around buggy encoders which drop the 00 padding
+ * byte. Do not use this function. */
+OPENSSL_EXPORT int BN_cbs2unsigned_buggy(CBS *cbs, BIGNUM *ret);
+
 /* BN_bn2cbb marshals |bn| as a non-negative DER INTEGER and appends the result
  * to |cbb|. It returns one on success and zero on failure. */
 OPENSSL_EXPORT int BN_bn2cbb(CBB *cbb, const BIGNUM *bn);
diff --git a/include/openssl/rsa.h b/include/openssl/rsa.h
index 53ca835..8e361da 100644
--- a/include/openssl/rsa.h
+++ b/include/openssl/rsa.h
@@ -338,6 +338,10 @@
  * error. */
 OPENSSL_EXPORT RSA *RSA_parse_public_key(CBS *cbs);
 
+/* RSA_parse_public_key_buggy behaves like |RSA_parse_public_key|, but it
+ * tolerates negative moduli. Do not use this function. */
+OPENSSL_EXPORT RSA *RSA_parse_public_key_buggy(CBS *cbs);
+
 /* RSA_public_key_from_bytes parses |in| as a DER-encoded RSAPublicKey structure
  * (RFC 3447). It returns a newly-allocated |RSA| or NULL on error. */
 OPENSSL_EXPORT RSA *RSA_public_key_from_bytes(const uint8_t *in, size_t in_len);