Coverage report: /home/ellis/comp/ext/ironclad/src/aead/eax.lisp

Kind	Covered	All	%
expression	0	325	0.0
branch	0	22	0.0

Key

Not instrumented

Conditionalized out

Executed

Not executed

Both branches taken

One branch taken

Neither branch taken

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;;;; eax.lisp -- Encrypt then authenticate then translate

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(in-package :crypto)

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(defclass eax (aead-mode)

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((cipher :accessor eax-cipher

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:initform nil)

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(mac-n :accessor eax-mac-n

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:initform nil)

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(mac-h :accessor eax-mac-h

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:initform nil)

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(mac-c :accessor eax-mac-c

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:initform nil)))

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 (defmethod shared-initialize :after ((mode eax) slot-names &rest initargs &key key cipher-name initialization-vector &allow-other-keys)

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(declare (ignore slot-names initargs))

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(let* ((mac-n (if (or (null (eax-mac-n mode)) cipher-name)

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(make-mac :cmac key cipher-name)

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(reinitialize-instance (eax-mac-n mode) :key key)))

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(mac-h (if (or (null (eax-mac-h mode)) cipher-name)

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(make-mac :cmac key cipher-name)

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(reinitialize-instance (eax-mac-h mode) :key key)))

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(mac-c (if (or (null (eax-mac-c mode)) cipher-name)

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(make-mac :cmac key cipher-name)

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(reinitialize-instance (eax-mac-c mode) :key key)))

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(block-length (block-length (or cipher-name (eax-cipher mode))))

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(buffer (make-array block-length

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:element-type '(unsigned-byte 8)

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:initial-element 0)))

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(update-mac mac-n buffer)

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(update-mac mac-n initialization-vector)

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(setf (aref buffer (1- (length buffer))) 1)

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(update-mac mac-h buffer)

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(setf (aref buffer (1- (length buffer))) 2)

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(update-mac mac-c buffer)

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(let* ((n (produce-mac mac-n))

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(cipher (if (or (null (eax-cipher mode)) cipher-name)

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(make-cipher cipher-name

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:key key

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:mode :ctr

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:initialization-vector n)

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(reinitialize-instance (eax-cipher mode)

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:key key

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:mode :ctr

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                                               :initialization-vector n))))

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(setf (eax-mac-n mode) mac-n

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(eax-mac-h mode) mac-h

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(eax-mac-c mode) mac-c

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(eax-cipher mode) cipher)))

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mode)

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(defmethod process-associated-data ((mode eax) data &key (start 0) end)

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(let* ((end (or end (length data))))

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(update-mac (eax-mac-h mode) data :start start :end end)))

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(defmethod produce-tag ((mode eax) &key tag (tag-start 0))

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(let* ((n (produce-mac (eax-mac-n mode)))

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(h (produce-mac (eax-mac-h mode)))

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(c (produce-mac (eax-mac-c mode)))

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(block-length (length c)))

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(etypecase tag

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(simple-octet-vector

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(when (> block-length (- (length tag) tag-start))

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(error 'insufficient-buffer-space

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:buffer tag

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:start tag-start

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:length block-length))

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(xor-block block-length n 0 c 0 c 0)

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(xor-block block-length h 0 c 0 tag tag-start)

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tag)

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(null

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(xor-block block-length n 0 c 0 c 0)

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(xor-block block-length h 0 c 0 c 0)

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c))))

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 (defmethod encrypt ((mode eax) plaintext ciphertext &key (plaintext-start 0) plaintext-end (ciphertext-start 0) handle-final-block)

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(declare (ignore handle-final-block))

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(let ((cipher (eax-cipher mode))

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(mac-c (eax-mac-c mode))

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(plaintext-end (or plaintext-end (length plaintext))))

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(multiple-value-bind (consumed-bytes produced-bytes)

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(encrypt cipher plaintext ciphertext

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:plaintext-start plaintext-start :plaintext-end plaintext-end

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:ciphertext-start ciphertext-start)

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(update-mac mac-c ciphertext

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:start ciphertext-start :end (+ ciphertext-start produced-bytes))

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(values consumed-bytes produced-bytes))))

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 (defmethod decrypt ((mode eax) ciphertext plaintext &key (ciphertext-start 0) ciphertext-end (plaintext-start 0) handle-final-block)

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(let ((cipher (eax-cipher mode))

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(mac-c (eax-mac-c mode))

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(ciphertext-end (or ciphertext-end (length ciphertext))))

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(update-mac mac-c ciphertext

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:start ciphertext-start :end ciphertext-end)

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(multiple-value-bind (consumed-bytes produced-bytes)

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(decrypt cipher ciphertext plaintext

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:ciphertext-start ciphertext-start :ciphertext-end ciphertext-end

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:plaintext-start plaintext-start)

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(when (and handle-final-block (tag mode))

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(let ((correct-tag (tag mode))

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(tag (produce-tag mode)))

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(unless (constant-time-equal tag correct-tag)

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(error 'bad-authentication-tag))))

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(values consumed-bytes produced-bytes))))

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 (defmethod encrypt-message ((mode eax) message &key (start 0) end associated-data (associated-data-start 0) associated-data-end &allow-other-keys)

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(let* ((length (- (or end (length message)) start))

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(encrypted-message (make-array length :element-type '(unsigned-byte 8))))

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(when associated-data

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(process-associated-data mode associated-data

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                                :start associated-data-start :end associated-data-end))

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(encrypt mode message encrypted-message

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:plaintext-start start :plaintext-end end)

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encrypted-message))

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 (defmethod decrypt-message ((mode eax) message &key (start 0) end associated-data (associated-data-start 0) associated-data-end &allow-other-keys)

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(let* ((length (- (or end (length message)) start))

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(decrypted-message (make-array length :element-type '(unsigned-byte 8))))

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(when associated-data

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(process-associated-data mode associated-data

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                                :start associated-data-start :end associated-data-end))

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(decrypt mode message decrypted-message

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:plaintext-start start :plaintext-end end

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:handle-final-block t)

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decrypted-message))

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(defaead eax)