Its really hard to say without seeing it, but to me that body language sounds very much like 'ooh exciting, who are you, i want to...' with the tail and the pulling towards them, but the ears say 'not sure, very stressful (stress can be good as well as bad!), high tension situation'...
So again I would err on the side of caution here, allow him to make the moves, and ideally let him greet someone for a few seconds then distract him and call him back to you for a reward, so that he doesnt end up 'out of his depth' (this also rewards him for coming away from the person, turning his back on them and leaving htme which can be a worrying issue for some dogs AND it reminds the other person that YOU are in charge and are actively training your dog..)
I have been thinking about my dogs and cuddles, and even those who actively like cuddles, still only really LIKE them when they have sought them out, on their terms. Neither Dilly nor Errol like cuddles that i choose to take (which i dont do very often but sometimes i do, because i am human too and i fluff up sometimes!), they tolerate them and have no reason to fear them, but close physical contact that I 'take' (rather than encourage or invite, or accept) is really only tolerated, not welcomed or enjoyed particularly.
With Ellie who is still learning that she CAN communicate with us and we WILL listen (even if we are silly clumsy humans and make mistakes), we are very careful that when she is soliciting attention, we stop, frequently to see if she asks us for more, rather than risk carrying on with a fuss or a scritch beyond the point shes happy with.
She can be perfectly happy with something she has instigated, and then change her mind, either its too much or the scritchy hand has wandered off the area she wanted touching, or the itch is gone... but just because its ok 'for now' doesnt mean its ok 'forever as long as you want to do it i dont care'.. because no one is like that! What might be nice for a few minutes can easily become weird and uncomfortable after even just a few minutes (imagine being hugged by someone you like well enough.... now imagine that hug goes on and on and on, and they cling and dont let go... and breathe in your ear.... it really wouldnt take long minutes at most, for that to go from fine, to 'earrrrrgh ugh get off me'!)