From: Ted Zlatanov Date: Sat, 14 Dec 2013 18:04:09 +0000 (-0500) Subject: New verify-error GnuTLS interface for certificate validation X-Git-Tag: emacs-24.3.90~173^2^2~42^2~45^2~387^2~410 X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=31b4827ea9ba8d22deb17c0593f0f555a33e1fa4;p=emacs.git New verify-error GnuTLS interface for certificate validation * net/gnutls.el (gnutls-verify-error): New defcustom to control the behavior when a certificate fails validation. Defaults to old behavior: never abort, just warn. (gnutls-negotiate): Use it. * gnutls.c: Replace `:verify_hostname_error' with `:verify_error', now a list of certificate validation checks that will abort a connection with an error. (Fgnutls_boot): Document it and use it. --- diff --git a/lisp/ChangeLog b/lisp/ChangeLog index f1f1f45df91..246b7ae5b5f 100644 --- a/lisp/ChangeLog +++ b/lisp/ChangeLog @@ -1,3 +1,10 @@ +2013-12-14 Teodor Zlatanov + + * net/gnutls.el (gnutls-verify-error): New defcustom to control + the behavior when a certificate fails validation. Defaults to + old behavior: never abort, just warn. + (gnutls-negotiate): Use it. + 2013-12-14 Martin Rudalics * window.el (display-buffer-below-selected): Never split window diff --git a/lisp/net/gnutls.el b/lisp/net/gnutls.el index 923b108c708..5bf9adc2b53 100644 --- a/lisp/net/gnutls.el +++ b/lisp/net/gnutls.el @@ -51,6 +51,19 @@ set this variable to \"normal:-dhe-rsa\"." :type '(choice (const nil) string)) +(defcustom gnutls-verify-error nil + "If non-nil, this should be a list of checks per hostname regex or t." + :group 'gnutls + :type '(choice + (const t) + (repeat :tag "List of hostname regexps with flags for each" + (list + (choice :tag "Hostname" + (const ".*" :tag "Any hostname") + regexp) + (set (const :trustfiles) + (const :hostname)))))) + (defcustom gnutls-trustfiles '( "/etc/ssl/certs/ca-certificates.crt" ; Debian, Ubuntu, Gentoo and Arch Linux @@ -138,19 +151,25 @@ MIN-PRIME-BITS is the minimum acceptable size of Diffie-Hellman keys \(see `gnutls-min-prime-bits' for more information). Use nil for the default. -When VERIFY-HOSTNAME-ERROR is not nil, an error will be raised -when the hostname does not match the presented certificate's host -name. The exact verification algorithm is a basic implementation -of the matching described in RFC2818 (HTTPS), which takes into -account wildcards, and the DNSName/IPAddress subject alternative -name PKIX extension. See GnuTLS' gnutls_x509_crt_check_hostname -for details. When VERIFY-HOSTNAME-ERROR is nil, only a warning -will be issued. +VERIFY-HOSTNAME-ERROR is a backwards compatibility option for +putting `:hostname' in VERIFY-ERROR. + +When VERIFY-ERROR is t or a list containing `:trustfiles', an +error will be raised when the peer certificate verification fails +as per GnuTLS' gnutls_certificate_verify_peers2. Otherwise, only +warnings will be shown about the verification failure. -When VERIFY-ERROR is not nil, an error will be raised when the -peer certificate verification fails as per GnuTLS' -gnutls_certificate_verify_peers2. Otherwise, only warnings will -be shown about the verification failure. +When VERIFY-ERROR is t or a list containing `:hostname', an error +will be raised when the hostname does not match the presented +certificate's host name. The exact verification algorithm is a +basic implementation of the matching described in +RFC2818 (HTTPS), which takes into account wildcards, and the +DNSName/IPAddress subject alternative name PKIX extension. See +GnuTLS' gnutls_x509_crt_check_hostname for details. Otherwise, +only a warning will be issued. + +Note that the list in `gnutls-verify-error', matched against the +HOSTNAME, is the default VERIFY-ERROR. VERIFY-FLAGS is a numeric OR of verification flags only for `gnutls-x509pki' connections. See GnuTLS' x509.h for details; @@ -183,8 +202,28 @@ defaults to GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT." (if gnutls-algorithm-priority (upcase gnutls-algorithm-priority) "NORMAL"))))) + (verify-error (or verify-error + ;; this uses the value of `gnutls-verify-error' + (cond + ;; if t, pass it on + ((eq gnutls-verify-error t) + t) + ;; if a list, look for hostname matches + ((listp gnutls-verify-error) + (mapcan + (lambda (check) + (when (string-match (car check) hostname) + (cdr check))) + gnutls-verify-error)) + ;; else it's nil + (t nil)))) (min-prime-bits (or min-prime-bits gnutls-min-prime-bits)) - (params `(:priority ,priority-string + params ret) + + (when verify-hostname-error + (push :hostname verify-error)) + + (setq params `(:priority ,priority-string :hostname ,hostname :loglevel ,gnutls-log-level :min-prime-bits ,min-prime-bits @@ -193,9 +232,7 @@ defaults to GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT." :keylist ,keylist :verify-flags ,verify-flags :verify-error ,verify-error - :verify-hostname-error ,verify-hostname-error :callbacks nil)) - ret) (gnutls-message-maybe (setq ret (gnutls-boot process type params)) diff --git a/src/ChangeLog b/src/ChangeLog index 80367c81166..081a6b8631c 100644 --- a/src/ChangeLog +++ b/src/ChangeLog @@ -1,3 +1,10 @@ +2013-12-14 Teodor Zlatanov + + * gnutls.c: Replace `:verify_hostname_error' with `:verify_error', + now a list of certificate validation checks that will abort a + connection with an error. + (Fgnutls_boot): Document it and use it. + 2013-12-14 Martin Rudalics * w32term.c (w32_enable_frame_resize_hack): New variable. diff --git a/src/gnutls.c b/src/gnutls.c index 105e5071ed7..a14d3ef31c5 100644 --- a/src/gnutls.c +++ b/src/gnutls.c @@ -50,7 +50,7 @@ static Lisp_Object QCgnutls_bootprop_loglevel; static Lisp_Object QCgnutls_bootprop_hostname; static Lisp_Object QCgnutls_bootprop_min_prime_bits; static Lisp_Object QCgnutls_bootprop_verify_flags; -static Lisp_Object QCgnutls_bootprop_verify_hostname_error; +static Lisp_Object QCgnutls_bootprop_verify_error; /* Callback keys for `gnutls-boot'. Unused currently. */ static Lisp_Object QCgnutls_bootprop_callbacks_verify; @@ -754,8 +754,12 @@ certificates for `gnutls-x509pki'. :verify-flags is a bitset as per GnuTLS' gnutls_certificate_set_verify_flags. -:verify-hostname-error, if non-nil, makes a hostname mismatch an -error. Otherwise it will be just a warning. +:verify-hostname-error is ignored. Pass :hostname in :verify-error +instead. + +:verify-error is a list of symbols to express verification checks or +`t' to do all checks. Currently it can contain `:trustfiles' and +`:hostname' to verify the certificate or the hostname respectively. :min-prime-bits is the minimum accepted number of bits the client will accept in Diffie-Hellman key exchange. @@ -799,8 +803,7 @@ one trustfile (usually a CA bundle). */) /* Lisp_Object callbacks; */ Lisp_Object loglevel; Lisp_Object hostname; - /* Lisp_Object verify_error; */ - Lisp_Object verify_hostname_error; + Lisp_Object verify_error; Lisp_Object prime_bits; CHECK_PROCESS (proc); @@ -819,11 +822,14 @@ one trustfile (usually a CA bundle). */) keylist = Fplist_get (proplist, QCgnutls_bootprop_keylist); crlfiles = Fplist_get (proplist, QCgnutls_bootprop_crlfiles); loglevel = Fplist_get (proplist, QCgnutls_bootprop_loglevel); - verify_hostname_error = Fplist_get (proplist, QCgnutls_bootprop_verify_hostname_error); + verify_error = Fplist_get (proplist, QCgnutls_bootprop_verify_error); prime_bits = Fplist_get (proplist, QCgnutls_bootprop_min_prime_bits); + if (!Flistp (verify_error)) + error ("gnutls-boot: invalid :verify_error parameter (not a list)"); + if (!STRINGP (hostname)) - error ("gnutls-boot: invalid :hostname parameter"); + error ("gnutls-boot: invalid :hostname parameter (not a string)"); c_hostname = SSDATA (hostname); state = XPROCESS (proc)->gnutls_state; @@ -1065,14 +1071,17 @@ one trustfile (usually a CA bundle). */) if (peer_verification != 0) { - if (NILP (verify_hostname_error)) - GNUTLS_LOG2 (1, max_log_level, "certificate validation failed:", - c_hostname); - else - { + if (EQ (verify_error, Qt) + || !NILP (Fmember (QCgnutls_bootprop_trustfiles, verify_error))) + { emacs_gnutls_deinit (proc); error ("Certificate validation failed %s, verification code %d", c_hostname, peer_verification); + } + else + { + GNUTLS_LOG2 (1, max_log_level, "certificate validation failed:", + c_hostname); } } @@ -1112,14 +1121,17 @@ one trustfile (usually a CA bundle). */) if (!fn_gnutls_x509_crt_check_hostname (gnutls_verify_cert, c_hostname)) { - if (NILP (verify_hostname_error)) - GNUTLS_LOG2 (1, max_log_level, "x509 certificate does not match:", - c_hostname); - else - { + if (EQ (verify_error, Qt) + || !NILP (Fmember (QCgnutls_bootprop_hostname, verify_error))) + { fn_gnutls_x509_crt_deinit (gnutls_verify_cert); emacs_gnutls_deinit (proc); error ("The x509 certificate does not match \"%s\"", c_hostname); + } + else + { + GNUTLS_LOG2 (1, max_log_level, "x509 certificate does not match:", + c_hostname); } } fn_gnutls_x509_crt_deinit (gnutls_verify_cert); @@ -1179,7 +1191,7 @@ syms_of_gnutls (void) DEFSYM (QCgnutls_bootprop_min_prime_bits, ":min-prime-bits"); DEFSYM (QCgnutls_bootprop_loglevel, ":loglevel"); DEFSYM (QCgnutls_bootprop_verify_flags, ":verify-flags"); - DEFSYM (QCgnutls_bootprop_verify_hostname_error, ":verify-hostname-error"); + DEFSYM (QCgnutls_bootprop_verify_error, ":verify-error"); DEFSYM (Qgnutls_e_interrupted, "gnutls-e-interrupted"); Fput (Qgnutls_e_interrupted, Qgnutls_code,