Add DebianBanner server configuration option

Setting this to "no" causes sshd to omit the Debian revision from its
initial protocol handshake, for those scared by package-versioning.patch.

Bug-Debian: http://bugs.debian.org/562048
Forwarded: not-needed
Last-Update: 2020-02-21

Patch-Name: debian-banner.patch

1 files changed, 9 insertions, 0 deletions

diff --git a/servconf.c b/servconf.c
index bf3cd84a4..7bbc25c2e 100644
--- a/servconf.c
+++ b/servconf.c
@@ -194,6 +194,7 @@ initialize_server_options(ServerOptions *options)
         options->fingerprint_hash = -1;
         options->disable_forwarding = -1;
         options->expose_userauth_info = -1;
+        options->debian_banner = -1;
 }
 
 /* Returns 1 if a string option is unset or set to "none" or 0 otherwise. */
@@ -468,6 +469,8 @@ fill_default_server_options(ServerOptions *options)
                 options->expose_userauth_info = 0;
         if (options->sk_provider == NULL)
                 options->sk_provider = xstrdup("internal");
+        if (options->debian_banner == -1)
+                options->debian_banner = 1;
 
         assemble_algorithms(options);
 
@@ -556,6 +559,7 @@ typedef enum {
         sStreamLocalBindMask, sStreamLocalBindUnlink,
         sAllowStreamLocalForwarding, sFingerprintHash, sDisableForwarding,
         sExposeAuthInfo, sRDomain, sPubkeyAuthOptions, sSecurityKeyProvider,
+        sDebianBanner,
         sDeprecated, sIgnore, sUnsupported
 } ServerOpCodes;
 
@@ -719,6 +723,7 @@ static struct {
         { "rdomain", sRDomain, SSHCFG_ALL },
         { "casignaturealgorithms", sCASignatureAlgorithms, SSHCFG_ALL },
         { "securitykeyprovider", sSecurityKeyProvider, SSHCFG_GLOBAL },
+        { "debianbanner", sDebianBanner, SSHCFG_GLOBAL },
         { NULL, sBadOption, 0 }
 };
 
@@ -2382,6 +2387,10 @@ process_server_config_line_depth(ServerOptions *options, char *line,
                         *charptr = xstrdup(arg);
                 break;
 
+        case sDebianBanner:
+                intptr = &options->debian_banner;
+                goto parse_flag;
+
         case sDeprecated:
         case sIgnore:
         case sUnsupported: