* Mitigate OpenSSL security vulnerability:

  - Add key blacklisting support. Keys listed in
    /etc/ssh/blacklist.TYPE-LENGTH will be rejected for authentication by
    sshd, unless "PermitBlacklistedKeys yes" is set in
    /etc/ssh/sshd_config.
  - Add a new program, ssh-vulnkey, which can be used to check keys
    against these blacklists.
  - Depend on openssh-blacklist.
  - Force dependencies on libssl0.9.8 / libcrypto0.9.8-udeb to at least
    0.9.8g-9.
  - Automatically regenerate known-compromised host keys, with a
    critical-priority debconf note. (I regret that there was no time to
    gather translations.)

1 files changed, 15 insertions, 0 deletions

diff --git a/sshd.c b/sshd.c
index add61cc5f..2d428967c 100644
--- a/sshd.c
+++ b/sshd.c
@@ -1466,6 +1466,21 @@ main(int ac, char **av)
 
         for (i = 0; i < options.num_host_key_files; i++) {
                 key = key_load_private(options.host_key_files[i], "", NULL);
+                if (key && blacklisted_key(key)) {
+                        char *fp;
+                        fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
+                        if (options.permit_blacklisted_keys)
+                                error("Host key %s blacklisted (see "
+                                    "ssh-vulnkey(1)); continuing anyway", fp);
+                        else
+                                error("Host key %s blacklisted (see "
+                                    "ssh-vulnkey(1))", fp);
+                        xfree(fp);
+                        if (!options.permit_blacklisted_keys) {
+                                sensitive_data.host_keys[i] = NULL;
+                                continue;
+                        }
+                }
                 sensitive_data.host_keys[i] = key;
                 if (key == NULL) {
                         error("Could not load host key: %s",