gnu: Add BLAKE3 command line tool.

* gnu/packages/crypto.scm (b3sum): New variable.

gnu/packages/crypto.scm

@@ -1571,3 +1571,52 @@ SHA-3, and BLAKE2.")
     ;; Users may choose between these two licenses when redistributing the
     ;; program provided by this package.
     (license (list license:cc0 license:asl2.0))))
+
+(define-public b3sum
+  (package
+    (name "b3sum")
+    ;; Version 1 requires Rust >= 1.51.
+    ;; <https://github.com/BLAKE3-team/BLAKE3/releases/tag/1.0.0>
+    (version "0.3.8")
+    (source
+      (origin
+        (method url-fetch)
+        (uri (crate-uri "b3sum" version))
+        (file-name (string-append name "-" version ".tar.gz"))
+        (sha256
+          (base32 "0h3fz16q5lk6mg7r8kjkjrq5hd4injngn5m7pswjbf2pyzjmg4b4"))))
+    (build-system cargo-build-system)
+    (arguments
+      `(;; Install the source so that Cargo.toml is installed, because that is
+        ;; the only reference to the license information.
+        #:install-source? #t
+        #:phases
+        (modify-phases %standard-phases
+          (add-before 'check 'patch-tests
+            (lambda _
+              (substitute* "tests/cli_tests.rs"
+                (("/bin/sh") (which "sh")))))
+          (add-after 'install 'install-doc
+            (lambda* (#:key outputs #:allow-other-keys)
+              (let* ((out (assoc-ref outputs "out"))
+                     (doc (string-append out "/share/doc/" ,name "-"
+                                         ,(package-version this-package))))
+                (install-file "README.md" doc)))))
+        #:cargo-inputs
+        (("rust-anyhow" ,rust-anyhow-1)
+         ("rust-blake3" ,rust-blake3-0.3)
+         ("rust-clap" ,rust-clap-2)
+         ("rust-hex" ,rust-hex-0.4)
+         ("rust-memmap" ,rust-memmap-0.7)
+         ("rust-rayon" ,rust-rayon-1)
+         ("rust-wild" ,rust-wild-2))
+        #:cargo-development-inputs
+        (("rust-duct" ,rust-duct-0.13)
+         ("rust-tempfile" ,rust-tempfile-3))))
+    (home-page "https://github.com/BLAKE3-team/BLAKE3")
+    (synopsis "Command line BLAKE3 checksum tool")
+    (description "This package provides @code{b3sum}, a command line
+checksum tool based on the BLAKE3 cryptographic hash function.")
+    ;; Users may choose between these two licenses when redistributing the
+    ;; program provided by this package.
+    (license (list license:cc0 license:asl2.0))))