https://www.govtrack.us/congress/bills/112/hr347/summaryThis bill made it a federal crime to trespass on the White House grounds, and it made other minor changes to an existing law.
This bill amended a previously existing law, which can be read here, that was also about establishing a crime of being in restricted areas protected by the Secret Service. This bill's only significant change was adding the White House to the list of restricted places.
Some say those existing provisions made protests illegal at political events where the Secret Service is protecting a candidate for office. Our understanding is that this is incorrect. The law applies to "cordoned off" areas or where a restriction is posted and where the general public has been cleared from. Additionally, it is unlikely the courts would uphold a restriction on access based on a political viewpoint.