Cal. Penal Code § 4573.6

(a) Any person who knowingly has in his or her possession in any state prison, prison road camp, prison forestry camp, or other prison camp or prison farm or any place where prisoners of the state are located under the custody of prison officials, officers, or employees, or in any county, city and county, or city jail, road camp, farm, or any place or institution, where prisoners or inmates are being held under the custody of any sheriff, chief of police, peace officer, probation officer, or employees, or within the grounds belonging to any jail, road camp, farm, place or institution, any controlled substances, the possession of which is prohibited by Division 10 (commencing with Section 11000) of the Health and Safety Code, any device, contrivance, instrument, or paraphernalia intended to be used for unlawfully injecting or consuming controlled substances, without being authorized to so possess the same by the rules of the Department of Corrections, rules of the prison or jail, institution, camp, farm or place, or by the specific authorization of the warden, superintendent, jailer, or other person in charge of the prison, jail, institution, camp, farm or place, is guilty of a felony punishable by imprisonment pursuant to subdivision (h) of Section 1170 for two, three, or four years. (b) The prohibitions and sanctions addressed in this section shall be clearly and prominently posted outside of, and at the entrance to, the grounds of all detention facilities under the jurisdiction of, or operated by, the state or any city, county, or city and county.