Sahih Muslim Book 7, Hadith Number 2648.

Chapter : What is permitted for the Muhrim (wearer of Ihram) in Hajj and Umra, what is not permissible and forbiddance of the use of perfume.

Salim reported on the authority of his father (‘Abdullah b. ‘Umar) that the Apostle of Allah (may peace be upon him) was asked what a Muhrim should wear, whereupon he said: A Muhrim should not wear a shirt, or a turban, or a cap, or trousers, or a cloth touched with wars or with saffron, nor (should he wear) stockings, but in case he does not find shoes, but (before wearing stockings) be should trim them (in such a way) that these should become lower than the ankles.