Genesis 9:18

And the sons of Noah who went forth from the ark were Shem, Cham, and Japhet; and Cham is the father of Kenaan.

AND HAM IS THE FATHER OF CANAAN. Rashi explained, “Because this section goes on to deal with Noah’s family, relating that Ham sinned and through him Canaan was cursed, and since the generations of Ham have not yet been mentioned [to let us know that Canaan was his son], it was necessary to state here that Ham is the father of Canaan.”
And Rabbi Abraham ibn Ezra said that Ham only saw the nakedness of his father and informed his brothers while Canaan did him the evil, the nature of which Scripture does not reveal, and this is the meaning of the verse, And he knew what his youngest son had done unto him, since Canaan was the youngest of Ham’s sons, as Scripture enumerates them, And the sons of Ham: Cush, and Mitzraim, and Phut, and Canaan. [Ibn Ezra thus interprets “son” to mean “grandson.”] Now here Rabbi Abraham ibn Ezra abandoned his method of explaining Scripture according to its plain meaning and began to declare statements contrary to the truth.
The correct interpretation appears to me to be that Ham was the youngest of Noah’s sons as I have explained at the beginning of this portion of the Torah, and Canaan was Ham’s oldest son. And as for the verse which states, And the sons of Ham: Cush, and Mitzraim, and Phut, and Canaan, [which indicates that Canaan was the youngest son], this was stated after he was sold to be a servant of servants; Scripture gave his brothers preference over him. Now when this event happened to Noah, Ham had no other children except Canaan. This explains the verse, And Ham, the father of Canaan, saw, for Ham had no other son then, and when he sinned unto his father, he cursed his seed. Now if Noah had said, “cursed be Ham, a servant of servants shall he be,” the punishment would have been only his since the seed already born to him is not part of him, and perhaps Ham would no longer beget children. In that case Noah would not have taken his vengeance of him for who knows what shall be after him. Therefore, he cursed the son he had. Even if he will later beget a hundred children,, 6:3. it is enough that the oldest son — and all his seed with him — were cursed.
The sin committed was that Ham saw the nakedness of his father and did not act respectfully. He should have covered his nakedness and concealed his shame by not telling even his brothers, but he told the matter to his two brothers in the presence of many people in order to deride him [Noah]. This is the meaning of the word outside. (Verse 22.) And so did Onkelos translate it as “in the market-place.” The meaning of the verse, And [Noah] knew what he had done unto him, is that he knew that Ham had disclosed his disgrace to many, and he was ashamed of the matter. Our Rabbis have mentioned an additional sin that Ham committed.

וחם הוא אבי כנען, he was similar in his conduct to his son Canaan, who was famous as being evil. Such descriptions implying “like father like son,” are also found, for instance in Ezekiel 16,3 אביך האמורי, “your father the Emorite,” (meaning that the prophet chides Israel for its actions saying these could make one think that Israel’s ancestor had been the Emorite,” (one of the Canaanite tribes).

ויהיו בני נח, a reminder that when Noach’s sons came out of the ark they did not have any offspring as yet. They begat offspring only afterwards, and from their children mankind as we know it is descended.

וחם הוא אבי כנען, this is mentioned as background to the story of Noach and the, wine.