From c14271c589cc546e1f2b5dffcfa7ad5e7cfadc2c Mon Sep 17 00:00:00 2001
From: John Kohl <jtkohl@mit.edu>
Date: Thu, 29 Mar 1990 16:01:40 +0000
Subject: [PATCH] *** empty log message ***

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@429 dc483132-0cff-0310-8789-dd5450dbe970
---
 src/lib/krb5/os/sendto_kdc.c | 169 +++++++++++++++++++++++++++++++++++
 1 file changed, 169 insertions(+)
 create mode 100644 src/lib/krb5/os/sendto_kdc.c

diff --git a/src/lib/krb5/os/sendto_kdc.c b/src/lib/krb5/os/sendto_kdc.c
new file mode 100644
index 000000000..be74b8a39
--- /dev/null
+++ b/src/lib/krb5/os/sendto_kdc.c
@@ -0,0 +1,169 @@
+/*
+ * $Source$
+ * $Author$
+ *
+ * Copyright 1990 by the Massachusetts Institute of Technology.
+ *
+ * For copying and distribution information, please see the file
+ * <krb5/mit-copyright.h>.
+ *
+ * Send packet to KDC for realm; wait for response, retransmitting
+ * as necessary.
+ */
+
+#if !defined(lint) && !defined(SABER)
+static char rcsid_sendto_kdc_c[] =
+"$Id$";
+#endif	/* !lint & !SABER */
+
+#include <krb5/copyright.h>
+
+#include <krb5/krb5.h>
+#include <krb5/krb5_err.h>
+#include <errno.h>
+#include <krb5/ext-proto.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#define MAX_DGRAM_SIZE	4096		/* XXX! */
+#define MAX_TIMEOUT 30			/* XXX */
+#define TIMEOUT_SHIFT 2			/* XXX */
+
+#include <stdio.h>
+#include <krb5/libos-proto.h>
+
+/*
+ * send the formatted request 'message' to a KDC for realm 'realm' and
+ * return the response (if any) in 'reply'.
+ *
+ * If the message is sent and a response is received, 0 is returned,
+ * otherwise an error code is returned.
+ *
+ * The storage for 'reply' is allocated and should be freed by the caller
+ * when finished.
+ *
+ */
+krb5_error_code
+krb5_sendto_kdc (DECLARG(krb5_data *, message),
+		 DECLARG(krb5_data *, realm),
+		 DECLARG(krb5_data *, reply))
+OLDDECLARG(krb5_data *, message)
+OLDDECLARG(krb5_data *, realm)
+OLDDECLARG(krb5_data *, reply)
+{
+    register int timeout, host, i;
+    struct sockaddr *addr;
+    int naddr;
+    int sent, nready;
+    krb5_error_code retval;
+    int socklist[AF_MAX];		/* one for each, if necessary! */
+    fd_set readable;
+    struct timeval waitlen;
+    struct sockaddr fromaddr;
+    int fromlen, cc;
+
+    /*
+     * find KDC location(s) for realm
+     */
+
+    if (retval = krb5_locate_kdc (realm, &addr, &naddr))
+	return retval;
+    if (naddr == 0)
+	return KRB5_REALM_UNKNOWN;
+    
+    for (i = 0; i < AF_MAX; i++)
+	socklist[i] = -1;
+
+    if (!(reply->data = malloc(MAX_DGRAM_SIZE))) { /* XXX size? */
+	free((char *)addr);
+	return ENOMEM;
+    }
+    reply->length = MAX_DGRAM_SIZE;
+
+    /*
+     * do exponential backoff.
+     */
+
+    for (timeout = 1; timeout < MAXTIMEOUT; timeout <<=TIMEOUT_SHIFT) {
+	sent = 0;
+	for (host = 0; host < naddr; host++) {
+	    /* send to the host, wait timeout seconds for a response,
+	       then move on. */
+	    /* cache some sockets for various address families in the
+	       list */
+	    if (socklist[addr[host].sa_family] == -1) {
+		/* XXX 4.2/4.3BSD has PF_xxx = AF_xxx, so the socket
+		   creation here will work properly... */
+		socklist[addr[host].sa_family] = socket(addr[host].sa_family,
+							SOCK_DGRAM,
+							0); /* XXX always zero? */
+		if (socklist[addr[host].sa_family] == -1)
+		    continue;		/* try other hosts */
+	    }
+	    /* have a socket to send/recv from */
+	    if (sendto(socklist[addr[host].sa_family],
+		       message->data,
+		       message->length,
+		       0,
+		       &addr[host],
+		       sizeof(addr[host])) != message->length)
+		continue;
+	    else
+		sent = 1;
+	    waitlen.tv_usec = 0;
+	    waitlen.tv_sec = timeout;
+	    FD_ZERO(&readable);
+	    FD_SET(socklist[addr[host].sa_family], &readable);
+	    if (nready = select(1<<socklist[addr[host].sa_family],
+				&readable,
+				0,
+				0,
+				&waitlen)) {
+		if (nready == -1)
+		    continue;		/* XXX */
+		if (cc = recvfrom(socklist[addr[host].sa_family],
+				  reply->data,
+				  reply->length,
+				  0,
+				  &fromaddr,
+				  &fromlen) == -1)
+		    continue;		/* XXX */
+		if (bcmp((char *)&fromaddr, (char *)&addr[host],
+			 fromlen)) {
+		    /* not from this one, perhaps from an earlier
+		       request? */
+		    for (i = host-1; i >= 0; i--) {
+			if (!bcmp((char *)&fromaddr, (char *)&addr[host],
+				  fromlen))
+			    break;
+		    }
+		    if (i < 0)		/* not from someone we asked */
+			continue;	/* XXX */
+		}
+		/* reply came from where we sent a request,
+		   so clean up and return. */
+		reply->length = cc;
+		retval = 0;
+		goto out;
+	    }
+	    /* not ready, go on to next server */
+	}
+	if (!sent) {
+	    /* never were able to send to any servers; give up */
+	    retval = KRB5_KDC_UNREACH;
+	    break;
+	}
+    }
+    retval = KRB5_KDC_UNREACH;
+ out:
+    for (i = 0; i < AF_MAX; i++)
+	(void) close(i);
+    free((char *)addr);
+    if (retval) {
+	free(reply->data);
+	reply->data = 0;
+	reply->length = 0;
+    }
+    return retval;
+}
-- 
2.26.2