Manual:Parameters to Special:Upload

The parameters to Special:Upload are wpSourceType, wpUpload, wpUploadIgnoreWarning, wpDestFile, wpUploadFile, wpUploadFile, wpLicense, wpDestFileWarningAck, wpIgnoreWarning, wpUploadIgnoreWarning, wpWatchthis, wpUploadCopyStatus, wpUploadSource, wpForReUpload, wpUploadDescription, wpCancelUpload, wpReUpload, and wpEditToken.