Yes in fact they are unless they are:
Crotalus viridis(Western rattlesnake), Crotalus atrox(Western diamondback rattlesnake), Crotalus ruber(red diamondback rattlesnake), Crotalus scutulatus(Mojave rattlesnake), Crotalus mitchelli(speckled rattlesnake) and Crotalus cerastes(Sidewinder)..
All other Elapidae, Viperidae, and Crotalidae are Illegal without a permit issued by the DFG...Naturally permits are not issued to Private individuals for 'pet' possession..