struct dirent **d);
static int gssd_get_single_krb5_cred(krb5_context context,
krb5_keytab kt, struct gssd_k5_kt_princ *ple);
-
+static int query_krb5_ccache(const char* cred_cache, char **ret_princname,
+ char **ret_realm);
/*
* Called from the scandir function to weed out potential krb5
int found = 0;
struct dirent *best_match_dir = NULL;
struct stat best_match_stat, tmp_stat;
+ char buf[1030];
+ char *princname = NULL;
+ char *realm = NULL;
+ int score, best_match_score = 0;
memset(&best_match_stat, 0, sizeof(best_match_stat));
*d = NULL;
else if (n > 0) {
char statname[1024];
for (i = 0; i < n; i++) {
- printerr(3, "CC file '%s' being considered\n",
- namelist[i]->d_name);
snprintf(statname, sizeof(statname),
"%s/%s", dirname, namelist[i]->d_name);
+ printerr(3, "CC file '%s' being considered, "
+ "with preferred realm '%s'\n",
+ statname, preferred_realm ?
+ preferred_realm : "<none selected>");
+ snprintf(buf, sizeof(buf), "FILE:%s/%s", dirname,
+ namelist[i]->d_name);
if (lstat(statname, &tmp_stat)) {
printerr(0, "Error doing stat on file '%s'\n",
statname);
}
/* Only pick caches owned by the user (uid) */
if (tmp_stat.st_uid != uid) {
- printerr(3, "'%s' owned by %u, not %u\n",
+ printerr(3, "CC file '%s' owned by %u, not %u\n",
statname, tmp_stat.st_uid, uid);
free(namelist[i]);
continue;
}
if (!S_ISREG(tmp_stat.st_mode)) {
- printerr(3, "'%s' is not a regular file\n",
+ printerr(3, "CC file '%s' is not a regular file\n",
+ statname);
+ free(namelist[i]);
+ continue;
+ }
+ if (!query_krb5_ccache(buf, &princname, &realm)) {
+ printerr(3, "CC file '%s' is expired or corrupt\n",
statname);
free(namelist[i]);
continue;
}
- printerr(3, "CC file '%s' matches owner check and has "
- "mtime of %u\n",
- namelist[i]->d_name, tmp_stat.st_mtime);
+
+ score = 0;
+ if (preferred_realm &&
+ strcmp(realm, preferred_realm) == 0)
+ score++;
+
+ printerr(3, "CC file '%s'(%s@%s) passed all checks and"
+ " has mtime of %u\n",
+ statname, princname, realm,
+ tmp_stat.st_mtime);
/*
* if more than one match is found, return the most
* recent (the one with the latest mtime), and
if (!found) {
best_match_dir = namelist[i];
best_match_stat = tmp_stat;
+ best_match_score = score;
found++;
}
else {
/*
- * If the current match has an mtime later
+ * If current score is higher than best match
+ * score, we use the current match. Otherwise,
+ * if the current match has an mtime later
* than the one we are looking at, then use
* the current match. Otherwise, we still
* have the best match.
*/
- if (tmp_stat.st_mtime >
- best_match_stat.st_mtime) {
+ if (best_match_score < score ||
+ (best_match_score == score &&
+ tmp_stat.st_mtime >
+ best_match_stat.st_mtime)) {
free(best_match_dir);
best_match_dir = namelist[i];
best_match_stat = tmp_stat;
+ best_match_score = score;
}
else {
free(namelist[i]);
}
- printerr(3, "CC file '%s' is our "
+ printerr(3, "CC file '%s/%s' is our "
"current best match "
"with mtime of %u\n",
- best_match_dir->d_name,
+ dirname, best_match_dir->d_name,
best_match_stat.st_mtime);
}
+ free(princname);
+ free(realm);
}
free(namelist);
}
return retval;
}
+
+static inline int data_is_equal(krb5_data d1, krb5_data d2)
+{
+ return (d1.length == d2.length
+ && memcmp(d1.data, d2.data, d1.length) == 0);
+}
+
+static int
+check_for_tgt(krb5_context context, krb5_ccache ccache,
+ krb5_principal principal)
+{
+ krb5_error_code ret;
+ krb5_creds creds;
+ krb5_cc_cursor cur;
+ int found = 0;
+
+ ret = krb5_cc_start_seq_get(context, ccache, &cur);
+ if (ret)
+ return 0;
+
+ while (!found &&
+ (ret = krb5_cc_next_cred(context, ccache, &cur, &creds)) == 0) {
+ if (creds.server->length == 2 &&
+ data_is_equal(creds.server->realm,
+ principal->realm) &&
+ creds.server->data[0].length == 6 &&
+ memcmp(creds.server->data[0].data,
+ "krbtgt", 6) == 0 &&
+ data_is_equal(creds.server->data[1],
+ principal->realm) &&
+ creds.times.endtime > time(NULL))
+ found = 1;
+ krb5_free_cred_contents(context, &creds);
+ }
+ krb5_cc_end_seq_get(context, ccache, &cur);
+
+ return found;
+}
+
+static int
+query_krb5_ccache(const char* cred_cache, char **ret_princname,
+ char **ret_realm)
+{
+ krb5_error_code ret;
+ krb5_context context;
+ krb5_ccache ccache;
+ krb5_principal principal;
+ int found = 0;
+ char *str = NULL;
+ char *princstring;
+
+ ret = krb5_init_context(&context);
+ if (ret)
+ return 0;
+
+ if(!cred_cache || krb5_cc_resolve(context, cred_cache, &ccache))
+ goto err_cache;
+
+ if (krb5_cc_set_flags(context, ccache, 0))
+ goto err_princ;
+
+ ret = krb5_cc_get_principal(context, ccache, &principal);
+ if (ret)
+ goto err_princ;
+
+ found = check_for_tgt(context, ccache, principal);
+ if (found) {
+ ret = krb5_unparse_name(context, principal, &princstring);
+ if (ret == 0) {
+ if ((str = strchr(princstring, '@')) != NULL) {
+ *str = '\0';
+ *ret_princname = strdup(princstring);
+ *ret_realm = strdup(str+1);
+ }
+ k5_free_unparsed_name(context, princstring);
+ } else {
+ found = 0;
+ }
+ }
+ krb5_free_principal(context, principal);
+err_princ:
+ krb5_cc_set_flags(context, ccache, KRB5_TC_OPENCLOSE);
+ krb5_cc_close(context, ccache);
+err_cache:
+ krb5_free_context(context);
+ return found;
+}
+
/*==========================*/
/*=== External routines ===*/
/*==========================*/
return error_message(code);
#endif
}
+
+/*
+ * Return default Kerberos realm
+ */
+void
+gssd_k5_get_default_realm(char **def_realm)
+{
+ krb5_context context;
+
+ if (krb5_init_context(&context))
+ return;
+
+ krb5_get_default_realm(context, def_realm);
+
+ krb5_free_context(context);
+}