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diff -up openssh-7.4p1/gss-serv-krb5.c.GSSAPIEnablek5users openssh-7.4p1/gss-serv-krb5.c
--- openssh-7.4p1/gss-serv-krb5.c.GSSAPIEnablek5users 2016-12-23 15:18:40.615216100 +0100
+++ openssh-7.4p1/gss-serv-krb5.c 2016-12-23 15:18:40.628216102 +0100
@@ -279,7 +279,6 @@ ssh_gssapi_krb5_cmdok(krb5_principal pri
FILE *fp;
char file[MAXPATHLEN];
char *line = NULL;
- char kuser[65]; /* match krb5_kuserok() */
struct stat st;
struct passwd *pw = the_authctxt->pw;
int found_principal = 0;
@@ -288,7 +287,7 @@ ssh_gssapi_krb5_cmdok(krb5_principal pri
snprintf(file, sizeof(file), "%s/.k5users", pw->pw_dir);
/* If both .k5login and .k5users DNE, self-login is ok. */
- if (!k5login_exists && (access(file, F_OK) == -1)) {
+ if ( !options.enable_k5users || (!k5login_exists && (access(file, F_OK) == -1))) {
return ssh_krb5_kuserok(krb_context, principal, luser,
k5login_exists);
}
diff -up openssh-7.4p1/servconf.c.GSSAPIEnablek5users openssh-7.4p1/servconf.c
--- openssh-7.4p1/servconf.c.GSSAPIEnablek5users 2016-12-23 15:18:40.615216100 +0100
+++ openssh-7.4p1/servconf.c 2016-12-23 15:35:36.354401156 +0100
@@ -168,6 +168,7 @@ initialize_server_options(ServerOptions
options->gss_store_rekey = -1;
options->gss_kex_algorithms = NULL;
options->use_kuserok = -1;
+ options->enable_k5users = -1;
options->password_authentication = -1;
options->kbd_interactive_authentication = -1;
options->permit_empty_passwd = -1;
@@ -345,6 +346,8 @@ fill_default_server_options(ServerOption
#endif
if (options->use_kuserok == -1)
options->use_kuserok = 1;
+ if (options->enable_k5users == -1)
+ options->enable_k5users = 0;
if (options->password_authentication == -1)
options->password_authentication = 1;
if (options->kbd_interactive_authentication == -1)
@@ -418,7 +421,7 @@ typedef enum {
sHostbasedUsesNameFromPacketOnly, sHostbasedAcceptedAlgorithms,
sHostKeyAlgorithms, sPerSourceMaxStartups, sPerSourceNetBlockSize,
sClientAliveInterval, sClientAliveCountMax, sAuthorizedKeysFile,
- sGssAuthentication, sGssCleanupCreds, sGssStrictAcceptor,
+ sGssAuthentication, sGssCleanupCreds, sGssEnablek5users, sGssStrictAcceptor,
sGssKeyEx, sGssKexAlgorithms, sGssStoreRekey,
sAcceptEnv, sSetEnv, sPermitTunnel,
sMatch, sPermitOpen, sPermitListen, sForceCommand, sChrootDirectory,
@@ -497,14 +500,16 @@ static struct {
{ "gssapikeyexchange", sGssKeyEx, SSHCFG_GLOBAL },
{ "gssapistorecredentialsonrekey", sGssStoreRekey, SSHCFG_GLOBAL },
{ "gssapikexalgorithms", sGssKexAlgorithms, SSHCFG_GLOBAL },
+ { "gssapienablek5users", sGssEnablek5users, SSHCFG_ALL },
#else
{ "gssapiauthentication", sUnsupported, SSHCFG_ALL },
{ "gssapicleanupcredentials", sUnsupported, SSHCFG_GLOBAL },
{ "gssapicleanupcreds", sUnsupported, SSHCFG_GLOBAL },
{ "gssapistrictacceptorcheck", sUnsupported, SSHCFG_GLOBAL },
{ "gssapikeyexchange", sUnsupported, SSHCFG_GLOBAL },
{ "gssapistorecredentialsonrekey", sUnsupported, SSHCFG_GLOBAL },
{ "gssapikexalgorithms", sUnsupported, SSHCFG_GLOBAL },
+ { "gssapienablek5users", sUnsupported, SSHCFG_ALL },
#endif
{ "gssusesessionccache", sUnsupported, SSHCFG_GLOBAL },
{ "gssapiusesessioncredcache", sUnsupported, SSHCFG_GLOBAL },
@@ -1653,6 +1658,10 @@ process_server_config_line(ServerOptions
intptr = &options->use_kuserok;
goto parse_flag;
+ case sGssEnablek5users:
+ intptr = &options->enable_k5users;
+ goto parse_flag;
+
case sMatch:
if (cmdline)
fatal("Match directive not supported as a command-line "
@@ -2026,6 +2035,7 @@ copy_set_server_options(ServerOptions *d
M_CP_INTOPT(ip_qos_interactive);
M_CP_INTOPT(ip_qos_bulk);
M_CP_INTOPT(use_kuserok);
+ M_CP_INTOPT(enable_k5users);
M_CP_INTOPT(rekey_limit);
M_CP_INTOPT(rekey_interval);
M_CP_INTOPT(log_level);
@@ -2320,6 +2330,7 @@ dump_config(ServerOptions *o)
# endif
dump_cfg_fmtint(sKerberosUniqueCCache, o->kerberos_unique_ccache);
dump_cfg_fmtint(sKerberosUseKuserok, o->use_kuserok);
+ dump_cfg_fmtint(sGssEnablek5users, o->enable_k5users);
#endif
#ifdef GSSAPI
dump_cfg_fmtint(sGssAuthentication, o->gss_authentication);
diff -up openssh-7.4p1/servconf.h.GSSAPIEnablek5users openssh-7.4p1/servconf.h
--- openssh-7.4p1/servconf.h.GSSAPIEnablek5users 2016-12-23 15:18:40.616216100 +0100
+++ openssh-7.4p1/servconf.h 2016-12-23 15:18:40.629216102 +0100
@@ -174,6 +174,7 @@ typedef struct {
int kerberos_unique_ccache; /* If true, the acquired ticket will
* be stored in per-session ccache */
int use_kuserok;
+ int enable_k5users;
int gss_authentication; /* If true, permit GSSAPI authentication */
int gss_keyex; /* If true, permit GSSAPI key exchange */
int gss_cleanup_creds; /* If true, destroy cred cache on logout */
diff -up openssh-7.4p1/sshd_config.5.GSSAPIEnablek5users openssh-7.4p1/sshd_config.5
--- openssh-7.4p1/sshd_config.5.GSSAPIEnablek5users 2016-12-23 15:18:40.630216103 +0100
+++ openssh-7.4p1/sshd_config.5 2016-12-23 15:36:21.607408435 +0100
@@ -628,6 +628,12 @@ Specifies whether to automatically destr
on logout.
The default is
.Cm yes .
+.It Cm GSSAPIEnablek5users
+Specifies whether to look at .k5users file for GSSAPI authentication
+access control. Further details are described in
+.Xr ksu 1 .
+The default is
+.Cm no .
.It Cm GSSAPIKeyExchange
Specifies whether key exchange based on GSSAPI is allowed. GSSAPI key exchange
doesn't rely on ssh keys to verify host identity.
diff -up openssh-7.4p1/sshd_config.GSSAPIEnablek5users openssh-7.4p1/sshd_config
--- openssh-7.4p1/sshd_config.GSSAPIEnablek5users 2016-12-23 15:18:40.616216100 +0100
+++ openssh-7.4p1/sshd_config 2016-12-23 15:18:40.631216103 +0100
@@ -80,6 +80,7 @@ GSSAPIAuthentication yes
#GSSAPICleanupCredentials yes
#GSSAPIStrictAcceptorCheck yes
#GSSAPIKeyExchange no
+#GSSAPIEnablek5users no
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
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