Below is the code for sharing photo on facebook using ASIHTTPRequest.

 - (void)publishStoryWithImage:(UIImage*)image andMessage:(NSString*)message
{
    NSURL *url = [NSURL URLWithString:@"https://graph.facebook.com/me/photos"];
    ASIFormDataRequest *newRequest = [ASIFormDataRequest requestWithURL:url];
    [newRequest setPostValue:message forKey:@"message"];
    NSData *imageData = UIImageJPEGRepresentation(image, 0.2f);
    [newRequest addData:imageData withFileName:@"testPicture" andContentType:@"multipart/form-data" forKey:@"source"];
    [newRequest setPostValue:yourAccessToken forKey:@"access_token"];
    [newRequest setRequestMethod:@"POST"];
    [newRequest setDidFinishSelector:@selector(postImageOnFacebookFinished:)];
    [newRequest setDidFailSelector:@selector(postImageOnFacebookfailed:)];
    [newRequest setDelegate:self];
    [newRequest startAsynchronous];

}