This code works fine for me:
<!-- facebook -->
<img src="[YOUR_FACEBOOK_PIC]" alt="Share on Facebook" onclick="window.open('https://www.facebook.com/sharer/sharer.php?u='+encodeURIComponent('[YOUR_PAGE_URL]'),'facebook-share-dialog','width=626,height=436'); return false;">
<!-- twitter -->
<img src="[YOUR_TWITTER_PIC]" alt="Share on Twitter" onclick="javascript:window.open('https://twitter.com/share?text=[SOME_TEXT_TO_PREPOLUTATE_TWEET]&url=[YOUR_PAGE_URL]','Twitter-dialog','width=626,height=436'); return false;">
<!-- google+ -->
<img src="[YOUR_GOOGLE_PIC]" alt="Share on Google Plus" onclick="window.open('https://plus.google.com/share?url=[YOUR_PAGE_URL]','Google-dialog','width=626,height=436'); return false;">
Just replace the text between brackets, and don't forget to "url encode" all the text that goes in the url to avoid issues.
And it doesn't need the SDK for any of them.
Here are references to the official documentation for each of them:
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…