diff --git a/include/libssh/packet.h b/include/libssh/packet.h
index 8fc7ce42..561bba8e 100644
--- a/include/libssh/packet.h
+++ b/include/libssh/packet.h
@@ -80,7 +80,7 @@ int ssh_packet_decrypt(ssh_session session, uint8_t *destination, uint8_t *sourc
         size_t start, size_t encrypted_size);
 unsigned char *ssh_packet_encrypt(ssh_session session,
                                   void *packet,
-                                  unsigned int len);
+                                  uint32_t len);
 int ssh_packet_hmac_verify(ssh_session session, const void *data, size_t len,
                            unsigned char *mac, enum ssh_hmac_e type);
 int ssh_packet_set_newkeys(ssh_session session,