diff options
Diffstat (limited to 'lisp/net/nsm.el')
| -rw-r--r-- | lisp/net/nsm.el | 85 |
1 files changed, 41 insertions, 44 deletions
diff --git a/lisp/net/nsm.el b/lisp/net/nsm.el index b59ea07d8a1..b0eff811617 100644 --- a/lisp/net/nsm.el +++ b/lisp/net/nsm.el @@ -204,54 +204,51 @@ SETTINGS are the same as those supplied to each check function. RESULTS is an alist where the keys are the checks run and the values the results of the checks.") +(defun nsm-network-same-subnet (local-ip mask ip) + "Returns t if IP is in the same subnet as LOCAL-IP/MASK. +LOCAL-IP, MASK, and IP are specified as vectors of integers, and +are expected to have the same length. Works for both IPv4 and +IPv6 addresses." + (let ((matches t) + (length (length local-ip))) + (unless (memq length '(4 5 8 9)) + (error "Unexpected length of IP address %S" local-ip)) + (dotimes (i length) + (setq matches (and matches + (= + (logand (aref local-ip i) + (aref mask i)) + (logand (aref ip i) + (aref mask i)))))) + matches)) + (defun nsm-should-check (host) "Determines whether NSM should check for TLS problems for HOST. If `nsm-trust-local-network' is or returns non-nil, and if the -host address is a localhost address, a machine address, a direct -link or a private network address, this function returns -nil. Non-nil otherwise." - (let* ((address (or (nslookup-host-ipv4 host nil 'vector) - (nslookup-host-ipv6 host nil 'vector))) - (ipv4? (eq (length address) 4))) - (not - (or (if ipv4? - (or - ;; (0.x.x.x) this machine - (eq (aref address 0) 0) - ;; (127.x.x.x) localhost - (eq (aref address 0) 0)) - (or - ;; (::) IPv6 this machine - (not (cl-mismatch address [0 0 0 0 0 0 0 0])) - ;; (::1) IPv6 localhost - (not (cl-mismatch address [0 0 0 0 0 0 0 1])))) - (and (or (and (functionp nsm-trust-local-network) - (funcall nsm-trust-local-network)) - nsm-trust-local-network) - (if ipv4? - (or - ;; (10.x.x.x) private - (eq (aref address 0) 10) - ;; (172.16.x.x) private - (and (eq (aref address 0) 172) - (eq (aref address 0) 16)) - ;; (192.168.x.x) private - (and (eq (aref address 0) 192) - (eq (aref address 0) 168)) - ;; (198.18.x.x) private - (and (eq (aref address 0) 198) - (eq (aref address 0) 18)) - ;; (169.254.x.x) link-local - (and (eq (aref address 0) 169) - (eq (aref address 0) 254))) - (memq (aref address 0) - '( - 64512 ;; (fc00::) IPv6 unique local address - 64768 ;; (fd00::) IPv6 unique local address - 65152 ;; (fe80::) IPv6 link-local - ) - ))))))) +host address is a localhost address, or in the same subnet as one +of the local interfaces, this function returns nil. Non-nil +otherwise." + (let ((addresses (network-lookup-address-info host)) + (network-interface-list (network-interface-list)) + (off-net t)) + (when + (or (and (functionp nsm-trust-local-network) + (funcall nsm-trust-local-network)) + nsm-trust-local-network) + (mapc + (lambda (address) + (mapc + (lambda (iface) + (let ((info (network-interface-info (car iface)))) + (when + (nsm-network-same-subnet (substring (car info) 0 -1) + (substring (car (cddr info)) 0 -1) + address) + (setq off-net nil)))) + network-interface-list)) + addresses)) + off-net)) (defun nsm-check-tls-connection (process host port status settings) "Check TLS connection against potential security problems. |