Move keytab_copy to krb5samba lib

This is a helper fucntion that uses purely krb5 code, so it belongs to
krb5samba which is the krb5 wrapper for samba.

3 files changed, 241 insertions, 1 deletions

diff --git a/lib/krb5_wrap/keytab_util.c b/lib/krb5_wrap/keytab_util.c
new file mode 100644
index 0000000000..12aca7f5a0
--- /dev/null
+++ b/lib/krb5_wrap/keytab_util.c
@@ -0,0 +1,229 @@
+/*
+ * Copyright (c) 1997-2004 Kungliga Tekniska Högskolan
+ * (Royal Institute of Technology, Stockholm, Sweden).
+ * Copyright (c) 2011 Andrew Bartlett
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "includes.h"
+#include "krb5_samba.h"
+
+static krb5_boolean
+compare_keyblock(const krb5_keyblock *a, const krb5_keyblock *b)
+{
+    if (KRB5_KEY_TYPE(a) != KRB5_KEY_TYPE(b) ||
+        KRB5_KEY_LENGTH(a) != KRB5_KEY_LENGTH(b) ||
+        memcmp(KRB5_KEY_DATA(a), KRB5_KEY_DATA(b), KRB5_KEY_LENGTH(a)) != 0)
+	return false;
+    return true;
+}
+
+static krb5_error_code copy_one_entry(krb5_context context,
+				      krb5_keytab src_keytab,
+				      krb5_keytab dst_keytab,
+				      krb5_keytab_entry entry)
+{
+    krb5_error_code ret;
+    krb5_keytab_entry dummy;
+
+    char *name_str;
+    char *etype_str;
+    ret = krb5_unparse_name (context, entry.principal, &name_str);
+    if(ret) {
+	krb5_set_error_message(context, ret, "krb5_unparse_name");
+	name_str = NULL; /* XXX */
+	return ret;
+    }
+    ret = smb_krb5_enctype_to_string(context,
+					KRB5_KEY_TYPE(KRB5_KT_KEY(&entry)),
+					&etype_str);
+    if(ret) {
+	krb5_set_error_message(context, ret, "krb5_enctype_to_string");
+	etype_str = NULL; /* XXX */
+	return ret;
+    }
+    ret = krb5_kt_get_entry(context, dst_keytab,
+			    entry.principal,
+			    entry.vno,
+			    KRB5_KEY_TYPE(KRB5_KT_KEY(&entry)),
+			    &dummy);
+    if(ret == 0) {
+	/* this entry is already in the new keytab, so no need to
+	   copy it; if the keyblocks are not the same, something
+	   is weird, so complain about that */
+	if (!compare_keyblock(KRB5_KT_KEY(&entry), KRB5_KT_KEY(&dummy))) {
+		DEBUG(2, ("copy_one_entry: entry with different keyvalue "
+			  "already exists for %s, keytype %s, kvno %d",
+			  name_str, etype_str, entry.vno));
+	}
+	krb5_kt_free_entry(context, &dummy);
+	krb5_kt_free_entry (context, &entry);
+	free(name_str);
+	free(etype_str);
+	return ret;
+    } else if(ret != KRB5_KT_NOTFOUND) {
+	krb5_set_error_message (context, ret, "fetching %s/%s/%u",
+				name_str, etype_str, entry.vno);
+	krb5_kt_free_entry (context, &entry);
+	free(name_str);
+	free(etype_str);
+	return ret;
+    }
+    ret = krb5_kt_add_entry (context, dst_keytab, &entry);
+    krb5_kt_free_entry (context, &entry);
+    if (ret) {
+	krb5_set_error_message (context, ret, "adding %s/%s/%u",
+				name_str, etype_str, entry.vno);
+	free(name_str);
+	free(etype_str);
+	return ret;
+    }
+    free(name_str);
+    free(etype_str);
+    return ret;
+}
+
+krb5_error_code kt_copy(krb5_context context, const char *from, const char *to)
+{
+    krb5_error_code ret;
+    krb5_keytab src_keytab, dst_keytab;
+    krb5_kt_cursor cursor;
+    krb5_keytab_entry entry;
+
+    ret = krb5_kt_resolve (context, from, &src_keytab);
+    if (ret) {
+	krb5_set_error_message (context, ret, "resolving src keytab `%s'", from);
+	return ret;
+    }
+
+    ret = krb5_kt_resolve (context, to, &dst_keytab);
+    if (ret) {
+	krb5_kt_close (context, src_keytab);
+	krb5_set_error_message (context, ret, "resolving dst keytab `%s'", to);
+	return ret;
+    }
+
+    ret = krb5_kt_start_seq_get (context, src_keytab, &cursor);
+    if (ret) {
+	krb5_set_error_message (context, ret, "krb5_kt_start_seq_get %s", from);
+	goto out;
+    }
+
+    while((ret = krb5_kt_next_entry(context, src_keytab,
+				    &entry, &cursor)) == 0) {
+	ret = copy_one_entry(context, src_keytab, dst_keytab, entry);
+	if (ret) {
+	    break;
+	}
+    }
+    krb5_kt_end_seq_get (context, src_keytab, &cursor);
+
+  out:
+    krb5_kt_close (context, src_keytab);
+    krb5_kt_close (context, dst_keytab);
+    if (ret == KRB5_KT_END) {
+	return 0;
+    } else if (ret == 0) {
+	return EINVAL;
+    }
+    return ret;
+}
+
+krb5_error_code kt_copy_one_principal(krb5_context context,
+				      const char *from,
+				      const char *to,
+				      const char *principal,
+				      krb5_kvno kvno,
+				      krb5_enctype *enctypes)
+{
+    krb5_error_code ret;
+    krb5_keytab src_keytab, dst_keytab;
+    krb5_keytab_entry entry;
+    krb5_principal princ;
+    int i;
+    bool found_one = false;
+
+    ret = krb5_parse_name (context, principal, &princ);
+    if(ret) {
+	    krb5_set_error_message(context, ret, "krb5_unparse_name");
+	    return ret;
+    }
+
+    ret = krb5_kt_resolve (context, from, &src_keytab);
+    if (ret) {
+	krb5_set_error_message(context, ret, "resolving src keytab `%s'", from);
+	return ret;
+    }
+
+    ret = krb5_kt_resolve (context, to, &dst_keytab);
+    if (ret) {
+	krb5_kt_close (context, src_keytab);
+	krb5_set_error_message(context, ret, "resolving dst keytab `%s'", to);
+	return ret;
+    }
+
+    for (i=0; enctypes[i]; i++) {
+  	ret = krb5_kt_get_entry(context, src_keytab,
+				princ,
+				kvno,
+				enctypes[i],
+				&entry);
+	if (ret == KRB5_KT_NOTFOUND) {
+	    continue;
+	} else if (ret) {
+	    break;
+	}
+	found_one = true;
+	ret = copy_one_entry(context, src_keytab, dst_keytab, entry);
+	if (ret) {
+	    break;
+	}
+    }
+    if (ret == KRB5_KT_NOTFOUND) {
+	if (!found_one) {
+	    char *princ_string;
+	    int ret2 = krb5_unparse_name (context, princ, &princ_string);
+	    if (ret2) {
+		krb5_set_error_message(context, ret,
+					"failed to fetch principal %s",
+					princ_string);
+	    }
+	} else {
+	    /* Not finding an enc type is not an error,
+	     * as long as we copied one for the principal */
+	    ret = 0;
+	}
+    }
+
+    krb5_kt_close (context, src_keytab);
+    krb5_kt_close (context, dst_keytab);
+    return ret;
+}
diff --git a/lib/krb5_wrap/krb5_samba.h b/lib/krb5_wrap/krb5_samba.h
index 864cda67bb..e2bd634d7a 100644
--- a/lib/krb5_wrap/krb5_samba.h
+++ b/lib/krb5_wrap/krb5_samba.h
@@ -241,6 +241,17 @@ bool unwrap_edata_ntstatus(TALLOC_CTX *mem_ctx,
 			   DATA_BLOB *edata,
 			   DATA_BLOB *edata_out);
 
+
+krb5_error_code kt_copy(krb5_context context,
+			const char *from,
+			const char *to);
+krb5_error_code kt_copy_one_principal(krb5_context context,
+				      const char *from,
+				      const char *to,
+				      const char *principal,
+				      krb5_kvno kvno,
+				      krb5_enctype *enctypes);
+
 #endif /* HAVE_KRB5 */
 
 int cli_krb5_get_ticket(TALLOC_CTX *mem_ctx,
diff --git a/lib/krb5_wrap/wscript_build b/lib/krb5_wrap/wscript_build
index c585819834..2a61f5633f 100755
--- a/lib/krb5_wrap/wscript_build
+++ b/lib/krb5_wrap/wscript_build
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 
 bld.SAMBA_LIBRARY('krb5samba',
-                  source='krb5_samba.c',
+                  source='krb5_samba.c keytab_util.c',
                   deps='samba-util asn1util talloc krb5 com_err',
 		  private_library=True
 		  )