diff --git a/library/rsa.c b/library/rsa.c
index d6abd65..7652f3d 100644
--- a/library/rsa.c
+++ b/library/rsa.c
@@ -1788,15 +1788,17 @@
 
 #if defined(MBEDTLS_PKCS1_V21)
 /*
- * Implementation of the PKCS#1 v2.1 RSASSA-PSS-SIGN function
+ * Implementation of the PKCS#1 v2.1 RSASSA-PSS-SIGN function with
+ * the option to pass in the salt length.
  */
-int mbedtls_rsa_rsassa_pss_sign( mbedtls_rsa_context *ctx,
+int mbedtls_rsa_rsassa_pss_sign_ext( mbedtls_rsa_context *ctx,
                          int (*f_rng)(void *, unsigned char *, size_t),
                          void *p_rng,
                          int mode,
                          mbedtls_md_type_t md_alg,
                          unsigned int hashlen,
                          const unsigned char *hash,
+                         int saltlen,
                          unsigned char *sig )
 {
     size_t olen;
@@ -1839,19 +1841,26 @@
 
     hlen = mbedtls_md_get_size( md_info );
 
-    /* Calculate the largest possible salt length. Normally this is the hash
-     * length, which is the maximum length the salt can have. If there is not
-     * enough room, use the maximum salt length that fits. The constraint is
-     * that the hash length plus the salt length plus 2 bytes must be at most
-     * the key length. This complies with FIPS 186-4 §5.5 (e) and RFC 8017
-     * (PKCS#1 v2.2) §9.1.1 step 3. */
-    min_slen = hlen - 2;
-    if( olen < hlen + min_slen + 2 )
-        return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
-    else if( olen >= hlen + hlen + 2 )
-        slen = hlen;
+    if (saltlen == MBEDTLS_RSA_SALT_LEN_ANY)
+    {
+        /* Calculate the largest possible salt length. Normally this is the hash
+        * length, which is the maximum length the salt can have. If there is not
+        * enough room, use the maximum salt length that fits. The constraint is
+        * that the hash length plus the salt length plus 2 bytes must be at most
+        * the key length. This complies with FIPS 186-4 §5.5 (e) and RFC 8017
+        * (PKCS#1 v2.2) §9.1.1 step 3. */
+        min_slen = hlen - 2;
+        if( olen < hlen + min_slen + 2 )
+            return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
+        else if( olen >= hlen + hlen + 2 )
+            slen = hlen;
+        else
+            slen = olen - hlen - 2;
+    }
     else
-        slen = olen - hlen - 2;
+    {
+        slen = (size_t)saltlen;
+    }
 
     memset( sig, 0, olen );
 
@@ -1909,6 +1918,22 @@
             ? mbedtls_rsa_public(  ctx, sig, sig )
             : mbedtls_rsa_private( ctx, f_rng, p_rng, sig, sig ) );
 }
+
+/*
+ * Implementation of the PKCS#1 v2.1 RSASSA-PSS-SIGN function
+ */
+int mbedtls_rsa_rsassa_pss_sign( mbedtls_rsa_context *ctx,
+                         int (*f_rng)(void *, unsigned char *, size_t),
+                         void *p_rng,
+                         int mode,
+                         mbedtls_md_type_t md_alg,
+                         unsigned int hashlen,
+                         const unsigned char *hash,
+                         unsigned char *sig )
+{
+    return mbedtls_rsa_rsassa_pss_sign_ext( ctx, f_rng, p_rng, mode, md_alg,
+                                                hashlen, hash, MBEDTLS_RSA_SALT_LEN_ANY, sig );
+}
 #endif /* MBEDTLS_PKCS1_V21 */
 
 #if defined(MBEDTLS_PKCS1_V15)