Not exactly chosen-plaintext; pedantically speaking it's blockwise-adaptive chosen plaintext. The distinction is important because provable resistance to regula

Not exactly chosen-plaintext; pedantically speaking it's blockwise-adaptive chosen plaintext. The distinction is important because provable resistance to regular chosen plaintext attacks (i.e., IND-CPA) is part of what kept broken modes around for so long---they're 'provably secure'!