diff options
Diffstat (limited to 'lisp/erc/erc-compat.el')
| -rw-r--r-- | lisp/erc/erc-compat.el | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/lisp/erc/erc-compat.el b/lisp/erc/erc-compat.el index d23703394be..4893f6ce594 100644 --- a/lisp/erc/erc-compat.el +++ b/lisp/erc/erc-compat.el @@ -273,6 +273,89 @@ If START or END is negative, it counts from the end." auth-source-backend-parser-functions)) +;;;; SASL + +(declare-function sasl-step-data "sasl" (step)) +(declare-function sasl-error "sasl" (datum)) +(declare-function sasl-client-property "sasl" (client property)) +(declare-function sasl-client-set-property "sasl" (client property value)) +(declare-function sasl-mechanism-name "sasl" (mechanism)) +(declare-function sasl-client-name "sasl" (client)) +(declare-function sasl-client-mechanism "sasl" (client)) +(declare-function sasl-read-passphrase "sasl" (prompt)) +(declare-function sasl-unique-id "sasl" nil) +(declare-function decode-hex-string "hex-util" (string)) +(declare-function rfc2104-hash "rfc2104" (hash block-length hash-length + key text)) +(declare-function sasl-scram--client-first-message-bare "sasl-scram-rfc" + (client)) +(declare-function cl-mapcar "cl-lib" (cl-func cl-x &rest cl-rest)) + +(defun erc-compat--29-sasl-scram-construct-gs2-header (client) + (let ((authzid (sasl-client-property client 'authenticator-name))) + (concat "n," (and authzid "a=") authzid ","))) + +(defun erc-compat--29-sasl-scram-client-first-message (client _step) + (let ((c-nonce (sasl-unique-id))) + (sasl-client-set-property client 'c-nonce c-nonce)) + (concat (erc-compat--29-sasl-scram-construct-gs2-header client) + (sasl-scram--client-first-message-bare client))) + +(defun erc-compat--29-sasl-scram--client-final-message + (hash-fun block-length hash-length client step) + (unless (string-match + "^r=\\([^,]+\\),s=\\([^,]+\\),i=\\([0-9]+\\)\\(?:$\\|,\\)" + (sasl-step-data step)) + (sasl-error "Unexpected server response")) + (let* ((hmac-fun + (lambda (text key) + (decode-hex-string + (rfc2104-hash hash-fun block-length hash-length key text)))) + (step-data (sasl-step-data step)) + (nonce (match-string 1 step-data)) + (salt-base64 (match-string 2 step-data)) + (iteration-count (string-to-number (match-string 3 step-data))) + (c-nonce (sasl-client-property client 'c-nonce)) + (cbind-input + (if (string-prefix-p c-nonce nonce) + (erc-compat--29-sasl-scram-construct-gs2-header client) ; *1 + (sasl-error "Invalid nonce from server"))) + (client-final-message-without-proof + (concat "c=" (base64-encode-string cbind-input t) "," ; *2 + "r=" nonce)) + (password + (sasl-read-passphrase + (format "%s passphrase for %s: " + (sasl-mechanism-name (sasl-client-mechanism client)) + (sasl-client-name client)))) + (salt (base64-decode-string salt-base64)) + (string-xor (lambda (a b) + (apply #'unibyte-string (cl-mapcar #'logxor a b)))) + (salted-password (let ((digest (concat salt (string 0 0 0 1))) + (xored nil)) + (dotimes (_i iteration-count xored) + (setq digest (funcall hmac-fun digest password)) + (setq xored (if (null xored) + digest + (funcall string-xor xored + digest)))))) + (client-key (funcall hmac-fun "Client Key" salted-password)) + (stored-key (decode-hex-string (funcall hash-fun client-key))) + (auth-message (concat "n=" (sasl-client-name client) + ",r=" c-nonce "," step-data + "," client-final-message-without-proof)) + (client-signature (funcall hmac-fun + (encode-coding-string auth-message 'utf-8) + stored-key)) + (client-proof (funcall string-xor client-key client-signature)) + (client-final-message + (concat client-final-message-without-proof "," + "p=" (base64-encode-string client-proof t)))) ; *3 + (sasl-client-set-property client 'auth-message auth-message) + (sasl-client-set-property client 'salted-password salted-password) + client-final-message)) + + ;;;; Misc 29.1 (defmacro erc-compat--with-memoization (table &rest forms) |