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needham-schroeder-pk.vp

Submitted on 28 Jun 20 21:20 UTC.

attacker[active]

principal Alice[
	knows private a
	generates na
	ga = G^a
]

principal Bob[
	knows private b
	generates nb
	gb = G^b
]

Alice -> Bob: [ga]

Bob -> Alice: gb

principal Alice[
	e1 = PKE_ENC(gb, na)
]

Alice -> Bob: e1

principal Bob[
	na_bob = PKE_DEC(b, e1)
	e2 = PKE_ENC(ga, CONCAT(na_bob, nb))
]

Bob -> Alice: e2

principal Alice[
	m2 = PKE_DEC(a, e2)
	na_bob_alice, nb_alice = SPLIT(m2)
	_ = ASSERT(na, na_bob_alice)?
	e3 = PKE_ENC(gb, nb_alice)
]

Alice -> Bob: [e3]

principal Bob[
	nb_alice_bob = PKE_DEC(b, e3)
	_ = ASSERT(nb, nb_alice_bob)?
]

queries[
	authentication? Alice -> Bob: e1
	authentication? Bob -> Alice: e2
	confidentiality? na
	confidentiality? nb
]

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Title:needham-schroeder-pk.vp Note over Alice: knows private a\n generates na\n ga = G^a\n Note over Bob: knows private b\n generates nb\n gb = G^b\n Alice -> Bob: [ga] Bob -> Alice: gb Note over Alice: e1 = PKE_ENC(gb, na)\n Alice -> Bob: e1 Note over Bob: na_bob = PKE_DEC(b, e1)\n e2 = PKE_ENC(ga, CONCAT(na_bob, nb))\n Bob -> Alice: e2 Note over Alice: m2 = PKE_DEC(a, e2)\n na_bob_alice, nb_alice = SPLIT(m2)\n _ = ASSERT(na, na_bob_alice)?\n e3 = PKE_ENC(gb, nb_alice)\n Alice -> Bob: [e3] Note over Bob: nb_alice_bob = PKE_DEC(b, e3)\n _ = ASSERT(nb, nb_alice_bob)?\n

Analysis Results

The model submitter provided the following analysis results:

Query 1 (Authentication): FAIL
Query 2 (Authentication): FAIL
Query 3 (Confidentiality): FAIL
Query 4 (Confidentiality): FAIL

Please note that these results are not verified to be accurate. The model submitter may choose to provide false analysis results if they so desire. It is strongly recommended that you re-run the analysis of this model locally if you wish to verify the authenticity of the analysis results above.

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