SimonG: They allowed a free download from their serves. They can end it at their discretion. Similar to what GOG did with Fallout 1. Nobody is saying Fallout 1 is freeware now.
Poulscath: Not quite the same. Fallout was a limited time offer. C&C is more like how Bethesda released Daggerfall and Arena.
That doesn't matter. They didn't forfeit their property to the game, they just offered the "gaming license" free. For how long you do it isn't an issue. Bethesda, EA or everybody who owns games that are given away for free can simply say "fsck you, from now I'll make you pay for them". But that doesn't render the copies you already have illegal, of course
Poulscath: I'm pretty sure they were released as freeware. In fact, according to a forum post I found on EAs site, EA themselves put one of the games on fileplanet.
Just checked, if you go to
here, there's a list of links to download the official Red Alert discs from
EAs sites. Check the EA.com mirror links. So they're still available, EA's just messed up the pages. (That link is a third party news post about the release)
As long as EA is giving them away, everything is legit. But, eg, you can't host them own your own website. And technically, you are no allowed to copy your copies for others. I'm pretty sure all those releases still contain an EULA and that EULA is, when it comes to the sensible parts, just as valid as the EULA of a bought game.