diff options
author | Philip Hazel <ph10@hermes.cam.ac.uk> | 2007-01-18 15:35:42 +0000 |
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committer | Philip Hazel <ph10@hermes.cam.ac.uk> | 2007-01-18 15:35:42 +0000 |
commit | 83da1223921fe30362e8374951360dcc8f21c4e7 (patch) | |
tree | 174a4beafbf240347d2ecad6d35640469baf96e8 /doc | |
parent | 7b90bba702ae0f7267931524c4c523c4ee9d46b6 (diff) |
Add gnutls_require_{kx,mac,protocols}.
Diffstat (limited to 'doc')
-rw-r--r-- | doc/doc-txt/ChangeLog | 5 | ||||
-rw-r--r-- | doc/doc-txt/NewStuff | 71 | ||||
-rw-r--r-- | doc/doc-txt/OptionLists.txt | 10 |
3 files changed, 82 insertions, 4 deletions
diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog index 240c815eb..238621e9b 100644 --- a/doc/doc-txt/ChangeLog +++ b/doc/doc-txt/ChangeLog @@ -1,4 +1,4 @@ -$Cambridge: exim/doc/doc-txt/ChangeLog,v 1.454 2007/01/17 11:17:58 ph10 Exp $ +$Cambridge: exim/doc/doc-txt/ChangeLog,v 1.455 2007/01/18 15:35:42 ph10 Exp $ Change log file for Exim from version 4.21 ------------------------------------------- @@ -26,6 +26,9 @@ PH/02 In an ACL statement such as PH/03 Added additional dnslists conditions == and =& which are different from = and & when the dns lookup returns more than one IP address. +PH/04 Added gnutls_require_{kx,mac,protocols} to give more control over the + cipher suites used by GnuTLS. These options are ignored by OpenSSL. + Exim version 4.66 ----------------- diff --git a/doc/doc-txt/NewStuff b/doc/doc-txt/NewStuff index 960f93ce8..9cc8f81cc 100644 --- a/doc/doc-txt/NewStuff +++ b/doc/doc-txt/NewStuff @@ -1,4 +1,4 @@ -$Cambridge: exim/doc/doc-txt/NewStuff,v 1.127 2007/01/17 11:17:58 ph10 Exp $ +$Cambridge: exim/doc/doc-txt/NewStuff,v 1.128 2007/01/18 15:35:42 ph10 Exp $ New Features in Exim -------------------- @@ -106,6 +106,75 @@ Version 4.67 When the DNS lookup yields only a single IP address, there is no difference between = and == and between & and =&. + 3. Up till now, the only control over which cipher suites GnuTLS uses has been + for the cipher algorithms. New options have been added to allow some of the + other parameters to be varied. Here is complete documentation for the + available features: + + GnuTLS allows the caller to specify separate lists of permitted key + exchange methods, main cipher algorithms, and MAC algorithms. These may be + used in any combination to form a specific cipher suite. This is unlike + OpenSSL, where complete cipher names can be passed to its control function. + GnuTLS also allows a list of acceptable protocols to be supplied. + + For compatibility with OpenSSL, the tls_require_ciphers option can be set + to complete cipher suite names such as RSA_ARCFOUR_SHA, but for GnuTLS this + option controls only the cipher algorithms. Exim searches each item in the + list for the name of an available algorithm. For example, if the list + contains RSA_AES_SHA, then AES is recognized, and the behaviour is exactly + the same as if just AES were given. + + There are additional options called gnutls_require_kx, gnutls_require_mac, + and gnutls_require_protocols that can be used to restrict the key exchange + methods, MAC algorithms, and protocols, respectively. These options are + ignored if OpenSSL is in use. + + All four options are available as global options, controlling how Exim + behaves as a server, and also as options of the smtp transport, controlling + how Exim behaves as a client. All the values are string expanded. After + expansion, the values must be colon-separated lists, though the separator + can be changed in the usual way. + + Each of the four lists starts out with a default set of algorithms. If the + first item in one of the "require" options does _not_ start with an + exclamation mark, all the default items are deleted. In this case, only + those that are explicitly specified can be used. If the first item in one + of the "require" items _does_ start with an exclamation mark, the defaults + are left on the list. + + Then, any item that starts with an exclamation mark causes the relevant + entry to be removed from the list, and any item that does not start with an + exclamation mark causes a new entry to be added to the list. Unrecognized + items in the list are ignored. Thus: + + tls_require_ciphers = !ARCFOUR + + allows all the defaults except ARCFOUR, whereas + + tls_require_ciphers = AES : 3DES + + allows only cipher suites that use AES or 3DES. For tls_require_ciphers + the recognized names are AES_256, AES_128, AES (both of the preceding), + 3DES, ARCFOUR_128, ARCFOUR_40, and ARCFOUR (both of the preceding). The + default list does not contain all of these; it just has AES_256, AES_128, + 3DES, and ARCFOUR_128. + + For gnutls_require_kx, the recognized names are DHE_RSA, RSA (which + includes DHE_RSA), DHE_DSS, and DHE (which includes both DHE_RSA and + DHE_DSS). The default list contains RSA, DHE_DSS, DHE_RSA. + + For gnutls_require_mac, the recognized names are SHA (synonym SHA1), and + MD5. The default list contains SHA, MD5. + + For gnutls_require_protocols, the recognized names are TLS1 and SSL3. + The default list contains TLS1, SSL3. + + In a server, the order of items in these lists is unimportant. The server + will advertise the availability of all the relevant cipher suites. However, + in a client, the order in the tls_require_ciphers list specifies a + preference order for the cipher algorithms. The first one in the client's + list that is also advertised by the server is tried first. + Version 4.66 ------------ diff --git a/doc/doc-txt/OptionLists.txt b/doc/doc-txt/OptionLists.txt index e484f98e9..67b03c793 100644 --- a/doc/doc-txt/OptionLists.txt +++ b/doc/doc-txt/OptionLists.txt @@ -1,4 +1,4 @@ -$Cambridge: exim/doc/doc-txt/OptionLists.txt,v 1.28 2006/12/05 11:35:28 ph10 Exp $ +$Cambridge: exim/doc/doc-txt/OptionLists.txt,v 1.29 2007/01/18 15:35:42 ph10 Exp $ LISTS OF EXIM OPTIONS --------------------- @@ -11,7 +11,7 @@ This file contains complete lists of four kinds of Exim option: 4. Those that can appear in the build time configuration for the Exim monitor (Local/eximon.conf). -This file was last updated for Exim release 4.64. +This file was last updated for Exim release 4.67. 1. RUN TIME OPTIONS @@ -231,6 +231,12 @@ from string* unset autoreply gecos_name string* unset main gecos_pattern string unset main gethostbyname boolean false smtp +gnutls_require_kx string* unset main 4.67 + string* unset smtp 4.67 +gnutls_require_mac string* unset main 4.67 + string* unset smtp 4.67 +gnutls_require_protocols string* unset main 4.67 + string* unset smtp 4.67 group string + routers 4.00 unset transports 4.00 replaces local option in some transports header_line_maxsize integer 0 (unset) main 4.14 |