Add and use k5memdup, k5memdup0 helpers

Add k5-int.h static functions to duplicate byte ranges, optionally
with a trailing zero byte, and set an error code like k5alloc does.
Use them where they would shorten existing code.

3 files changed, 7 insertions, 13 deletions

diff --git a/src/lib/kdb/kdb5.c b/src/lib/kdb/kdb5.c
index 2a040fc57c..e1ee5f9ff9 100644
--- a/src/lib/kdb/kdb5.c
+++ b/src/lib/kdb/kdb5.c
@@ -1167,16 +1167,13 @@ krb5_db_fetch_mkey(krb5_context context, krb5_principal mname,
         if (retval)
             goto clean_n_exit;
 
-        key->contents = malloc(tmp_key.length);
-        if (key->contents == NULL) {
-            retval = ENOMEM;
+        key->contents = k5memdup(tmp_key.contents, tmp_key.length, &retval);
+        if (key->contents == NULL)
             goto clean_n_exit;
-        }
 
         key->magic = tmp_key.magic;
         key->enctype = tmp_key.enctype;
         key->length = tmp_key.length;
-        memcpy(key->contents, tmp_key.contents, tmp_key.length);
     }
 
 clean_n_exit:
diff --git a/src/lib/kdb/kdb_default.c b/src/lib/kdb/kdb_default.c
index ee01d9d21c..9a7f757f96 100644
--- a/src/lib/kdb/kdb_default.c
+++ b/src/lib/kdb/kdb_default.c
@@ -361,12 +361,12 @@ krb5_db_def_fetch_mkey_keytab(krb5_context   context,
          * kt_ent will be free'd so need to allocate and copy key contents for
          * output to caller.
          */
-        if (!(key->contents = (krb5_octet *)malloc(key->length))) {
-            retval = ENOMEM;
+        key->contents = k5memdup(kt_ent.key.contents, kt_ent.key.length,
+                                 &retval);
+        if (key->contents == NULL) {
             krb5_kt_free_entry(context, &kt_ent);
             goto errout;
         }
-        memcpy(key->contents, kt_ent.key.contents, kt_ent.key.length);
         krb5_kt_free_entry(context, &kt_ent);
     }
 
diff --git a/src/lib/kdb/kdb_log.c b/src/lib/kdb/kdb_log.c
index b9906f0f72..d8d338c7fb 100644
--- a/src/lib/kdb/kdb_log.c
+++ b/src/lib/kdb/kdb_log.c
@@ -321,13 +321,10 @@ ulog_replay(krb5_context context, kdb_incr_result_t *incr_ret, char **db_args)
             continue;
 
         if (upd->kdb_deleted) {
-            dbprincstr = k5alloc(upd->kdb_princ_name.utf8str_t_len + 1,
-                                 &retval);
+            dbprincstr = k5memdup0(upd->kdb_princ_name.utf8str_t_val,
+                                   upd->kdb_princ_name.utf8str_t_len, &retval);
             if (dbprincstr == NULL)
                 goto cleanup;
-            memcpy(dbprincstr, (char *)upd->kdb_princ_name.utf8str_t_val,
-                   upd->kdb_princ_name.utf8str_t_len);
-            dbprincstr[upd->kdb_princ_name.utf8str_t_len] = '\0';
 
             retval = krb5_parse_name(context, dbprincstr, &dbprinc);
             free(dbprincstr);