		Search-engine friendly clone of the ACL2 documentation.

Interfaces

Sha-256-interface

SHA-256 is specified in the FIPS PUB 180-4 standard.

According to FIPS PUB 180-4, the input of SHA-256 is a sequence of less than 2^{64} bits, or less than 2^{61} bytes.

According to FIPS PUB 180-4, the output of SHA-256 is a sequence of exactly 256 bits, or 32 bytes.

Definitions and Theorems

Theorem: bit-list-of-sha-256-bits

(defthm bit-list-of-sha-256-bits
  (bit-listp (sha-256-bits bits)))

Theorem: byte-list-of-sha-256-bytes

(defthm byte-list-of-sha-256-bytes
  (byte-listp (sha-256-bytes bytes)))

Theorem: len-of-sha-256-bits

(defthm len-of-sha-256-bits
  (equal (len (sha-256-bits bits)) 256))

Theorem: len-of-sha-256-bytes

(defthm len-of-sha-256-bytes
  (equal (len (sha-256-bytes bytes)) 32))

Theorem: sha-256-bits-of-bit-list-fix-bits

(defthm sha-256-bits-of-bit-list-fix-bits
  (equal (sha-256-bits (acl2::bit-list-fix bits))
         (sha-256-bits bits)))

Theorem: sha-256-bits-bit-list-equiv-congruence-on-bits

(defthm sha-256-bits-bit-list-equiv-congruence-on-bits
  (implies (acl2::bit-list-equiv bits bits-equiv)
           (equal (sha-256-bits bits)
                  (sha-256-bits bits-equiv)))
  :rule-classes :congruence)

Theorem: sha-256-bytes-of-byte-list-fix-bytes

(defthm sha-256-bytes-of-byte-list-fix-bytes
  (equal (sha-256-bytes (byte-list-fix bytes))
         (sha-256-bytes bytes)))

Theorem: sha-256-bytes-byte-list-equiv-congruence-on-bytes

(defthm sha-256-bytes-byte-list-equiv-congruence-on-bytes
  (implies (byte-list-equiv bytes bytes-equiv)
           (equal (sha-256-bytes bytes)
                  (sha-256-bytes bytes-equiv)))
  :rule-classes :congruence)

Theorem: true-listp-of-sha-256-bits

(defthm true-listp-of-sha-256-bits
  (true-listp (sha-256-bits bits))
  :rule-classes :type-prescription)

Theorem: true-listp-of-sha-256-bytes

(defthm true-listp-of-sha-256-bytes
  (true-listp (sha-256-bytes bytes))
  :rule-classes :type-prescription)

Theorem: consp-of-sha-256-bits

(defthm consp-of-sha-256-bits
  (consp (sha-256-bits bits))
  :rule-classes :type-prescription)

Theorem: consp-of-sha-256-bytes

(defthm consp-of-sha-256-bytes
  (consp (sha-256-bytes bytes))
  :rule-classes :type-prescription)

Theorem: byte-list32p-of-sha-256-bytes

(defthm byte-list32p-of-sha-256-bytes
  (byte-list32p (sha-256-bytes bytes)))