I saw the Messenger of Allah ﷺ touching the Black Stone, so I never neglect touching it, whether in hardship or in ease.
حدثنا هشيم أخبرنا عبيد الله عن نافع
رأيت رسول الله ﷺ يستلم الحجر الأسود فلا أدع استلامه في شدة ولا رخاء
Its isnad is sahih. Ubaydullah is Ibn Umar bin Hafs bin Asim. Muslim also narrated it (1:360) with similar wording, from the route of Yahya from Ubaydullah from Nafi.