|
|
|
@ -536,15 +536,15 @@ The process between Alice and Bob verifying each other would be:
|
|
|
|
|
|
|
|
|
|
.. |AlicePublicKey| replace:: :math:`K_{A}^{public}`
|
|
|
|
|
.. |AlicePrivateKey| replace:: :math:`K_{A}^{private}`
|
|
|
|
|
.. |AliceCurve25519| replace:: :math:`K_{A}^{private}K_{A}^{public}`
|
|
|
|
|
.. |AliceCurve25519| replace:: :math:`K_{A}^{private},K_{A}^{public}`
|
|
|
|
|
.. |BobPublicKey| replace:: :math:`K_{B}^{public}`
|
|
|
|
|
.. |BobPrivateKey| replace:: :math:`K_{B}^{private}`
|
|
|
|
|
.. |BobCurve25519| replace:: :math:`K_{B}^{private}K_{B}^{public}`
|
|
|
|
|
.. |BobCurve25519| replace:: :math:`K_{B}^{private},K_{B}^{public}`
|
|
|
|
|
.. |AliceBobCurve25519| replace:: :math:`K_{A}^{private}K_{B}^{public}`
|
|
|
|
|
.. |BobAliceCurve25519| replace:: :math:`K_{B}^{private}K_{A}^{public}`
|
|
|
|
|
.. |AliceBobECDH| replace:: :math:`ECDH(K_{A}^{private},K_{B}^{public})`
|
|
|
|
|
|
|
|
|
|
1. Alice and Bob establish a secure connection, likely meeting in-person. "Secure"
|
|
|
|
|
1. Alice and Bob establish a secure out-of-band connection, such as meeting in-person or a video call. "Secure"
|
|
|
|
|
here means that either party cannot be impersonated, not explicit secrecy.
|
|
|
|
|
#. Alice and Bob communicate which devices they'd like to verify with each other.
|
|
|
|
|
#. Alice selects Bob's device from the device list and begins verification.
|
|
|
|
@ -573,9 +573,9 @@ The process between Alice and Bob verifying each other would be:
|
|
|
|
|
methods are available, clients should allow the users to select a method.
|
|
|
|
|
#. Alice and Bob compare the strings shown by their devices, and tell their devices if
|
|
|
|
|
they match or not.
|
|
|
|
|
#. Assuming they match, Alice and Bob's devices calculate the HMAC of their own device
|
|
|
|
|
#. Assuming they match, Alice and Bob's devices calculate the HMAC of their own device keys
|
|
|
|
|
and a comma-separated sorted list of of the key IDs that they wish the other user
|
|
|
|
|
to verify. HMAC is defined in RFC 2104, and SHA-256 as the hash function. The key for
|
|
|
|
|
to verify, using SHA-256 as the hash function. HMAC is defined in [RFC 2104](https://tools.ietf.org/html/rfc2104). The key for
|
|
|
|
|
the HMAC is different for each item and is calculated by generating 32 bytes (256 bits)
|
|
|
|
|
using `the key verification HKDF <#SAS-HKDF>`_.
|
|
|
|
|
#. Alice's device sends Bob's device a ``m.key.verification.mac`` message containing the
|
|
|
|
@ -619,7 +619,7 @@ At any point the interactive verfication can go wrong. The following describes w
|
|
|
|
|
to do when an error happens:
|
|
|
|
|
|
|
|
|
|
* Alice or Bob can cancel the verification at any time. A ``m.key.verification.cancel``
|
|
|
|
|
message must be sent to signify the cancelation.
|
|
|
|
|
message must be sent to signify the cancellation.
|
|
|
|
|
* The verification can time out. Clients should time out a verification that does not
|
|
|
|
|
complete within 5 minutes. Additionally, clients should expire a ``transaction_id``
|
|
|
|
|
which goes unused for 5 minutes after having last sent/received it. The client should
|
|
|
|
@ -668,8 +668,8 @@ are used in addition to those already specified:
|
|
|
|
|
HKDF calculation
|
|
|
|
|
<<<<<<<<<<<<<<<<
|
|
|
|
|
|
|
|
|
|
In all of the SAS methods, HKDF is as defined in RFC 5869 and uses the previously
|
|
|
|
|
agreed upon hash function for the hash function. The shared secret is supplied
|
|
|
|
|
In all of the SAS methods, HKDF is as defined in [RFC 5869](https://tools.ietf.org/html/rfc5869) and uses the previously
|
|
|
|
|
agreed-upon hash function for the hash function. The shared secret is supplied
|
|
|
|
|
as the input keying material. No salt is used, and the input parameter is the
|
|
|
|
|
concatenation of:
|
|
|
|
|
|
|
|
|
|