What is the source of this dua read in Witr prayer?

Question

What is the source of this dua (dua qunoot read in Witr prayer by people from Hanafi school)? Are these verses from holy Quran or Sunnah?

Allahumma inna nasta'inuka wa nastaghfiruka, wa nu'minu bika wa natawakkalu 'alaika wa nuthni 'alaikal khair, wa nashkuruka wa la nakfuruka wa nakhla'u wa natruka manyyafjuruka, allahumma iyyaka na'budu , wa laka nusalli wa nasjudu wa ilaika nas'a wa nahfidu wa narju rahmataka wa nakhsha 'adhabaka inna 'adhabaka bil kaffari mulhiq.

Answer 1

This du`a comes to us principally through an athar (narration) of `Abdullah ibn Mas`ud and collected in the Musannaf of Ibn Abi Shaybah, in Kitab as-Salah and the chapter of the du`a in the qunut of witr:

عن أبي عبد الرحمن قال : علمنا ابن مسعود أن نقرأ في القنوت : اللهم إنا نستعينك ونستغفرك ونؤمن بك ونثني عليك الخير ولا نكفرك ونخلع ونترك من يفجرك اللهم إياك نعبد ولك نصلي ونسجد وإليك نسعى ونحفد ونرجو رحمتك ونخشى عذابك إن عذابك الجد بالكفار ملحق . ¹

Slight variants of this du`a occur in other parts of the Musannaf as well (e.g. in the Book of Du`a and section on what to make du`a by in the qunut of Fajr ²).

For more information on the provenance of this du`a, check this answer³ from askimam and this post⁴ on ahlalhadeeth (section on nusus al-athar)

References:

1. http://www.islamweb.net/newlibrary/display_book.php?flag=1&bk_no=10&ID=763
2. http://www.islamweb.net/newlibrary/display_book.php?idfrom=4290&idto=4290&bk_no=10&ID=4029
3. http://www.askimam.org/public/question_detail/22316
4. http://www.ahlalhdeeth.com/vb/showthread.php?t=219108

Answer 2

No, this is neither from Qur'an or is a Sunnah of the Prophet (pbuh) but infact this hadith comes from Umar (RA) as it was reported that this was his sunnah.

It was narrated that ‘Umar prayed Qunoot with the following words:

“O’ Allah! We implore You for help and beg forgiveness of You and believe in You and rely on You and extol You and we are thankful to You and are not ungrateful to You and we alienate and forsake those who disobey You. O’ Allah! You alone do we worship and for You do we pray and prostrate and we betake to please You and present ourselves for the service in Your cause and we hope for Your mercy and fear Your chastisement. Undoubtedly, Your torment is going to overtake infidels” (Translation of Du'a e Qunoot)

(Narrated by al-Bayhaqi, 2/210; classed as saheeh by al-Albaani in al-Irwa’, 2/170)

May the creator guide us all.

_{Took support from Ansari's answer}