diff options
author | Dr. Stephen Henson <steve@openssl.org> | 2010-02-18 12:41:50 +0000 |
---|---|---|
committer | Dr. Stephen Henson <steve@openssl.org> | 2010-02-18 12:41:50 +0000 |
commit | 4f3d52fedcb6f0bcb9948346e9ebceb21d9cd8f4 (patch) | |
tree | bb3c37d1a2aee272ca8577eedb3cf1d51c1e7fda /doc | |
parent | 8321bab39c4cb6ccbf507060de2302403eea7764 (diff) |
clarify documentation
Diffstat (limited to 'doc')
-rw-r--r-- | doc/ssl/SSL_CTX_set_options.pod | 38 |
1 files changed, 25 insertions, 13 deletions
diff --git a/doc/ssl/SSL_CTX_set_options.pod b/doc/ssl/SSL_CTX_set_options.pod index 1abda2898e..310db84b31 100644 --- a/doc/ssl/SSL_CTX_set_options.pod +++ b/doc/ssl/SSL_CTX_set_options.pod @@ -224,10 +224,16 @@ of RFC4507bis tickets for stateless session resumption. If this option is set this functionality is disabled and tickets will not be used by clients or servers. -=item SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION, SSL_OP_LEGACY_SERVER_CONNECT +=item SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION -See the B<SECURE RENEGOTIATION> section for a discussion of the purpose of -these options. +Allow legacy insecure renegotiation between OpenSSL and unpatched clients or +servers. See the B<SECURE RENEGOTIATION> section for more details. + +=item SSL_OP_LEGACY_SERVER_CONNECT + +Allow legacy insecure renegotiation between OpenSSL and unpatched servers +B<only>: this option is currently set by default. See the +B<SECURE RENEGOTIATION> section for more details. =back @@ -275,15 +281,18 @@ was refused. =head2 Patched OpenSSL client and unpatched server. -If the option B<SSL_OP_LEGACY_SERVER_CONNECT> is set then initial connections +If the option B<SSL_OP_LEGACY_SERVER_CONNECT> or +B<SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION> is set then initial connections and renegotiation between patched OpenSSL clients and unpatched servers -succeeds. +succeeds. If neither option is set then initial connections to unpatched +servers will fail. -This option is currently set by default even though it has security -implications: otherwise it would be impossible to connect to unpatched servers -(i.e. all of them initially) and this is clearly not acceptable. Renegotiation -is permitted because this does not add any additional security issues: during -an attack clients do not see any renegotiations anyway. +The option B<SSL_OP_LEGACY_SERVER_CONNECT> is currently set by default even +though it has security implications: otherwise it would be impossible to +connect to unpatched servers (i.e. all of them initially) and this is clearly +not acceptable. Renegotiation is permitted because this does not add any +additional security issues: during an attack clients do not see any +renegotiations anyway. As more servers become patched the option B<SSL_OP_LEGACY_SERVER_CONNECT> will B<not> be set by default in a future version of OpenSSL. @@ -296,9 +305,12 @@ unpatched servers (and thus avoid any security issues) should always B<clear> B<SSL_OP_LEGACY_SERVER_CONNECT> using SSL_CTX_clear_options() or SSL_clear_options(). -As in the previous case if the option -B<SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION> is set then renegotiation -B<always> succeeds. +The difference between the B<SSL_OP_LEGACY_SERVER_CONNECT> and +B<SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION> options is that +B<SSL_OP_LEGACY_SERVER_CONNECT> enables initial connections and secure +renegotiation between OpenSSL clients and unpatched servers B<only>, while +B<SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION> allows initial connections +and renegotiation between OpenSSL and unpatched clients or servers. =head1 RETURN VALUES |