add CNS V4 library to tree for compatibility use. Installs as libkrb4.a

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@5537 dc483132-0cff-0310-8789-dd5450dbe970

1 files changed, 171 insertions, 0 deletions

diff --git a/src/lib/krb4/tf_shm.c b/src/lib/krb4/tf_shm.c
new file mode 100644
index 0000000000..bd08f7f722
--- /dev/null
+++ b/src/lib/krb4/tf_shm.c
@@ -0,0 +1,171 @@
+/*
+ * tf_shm.c
+ *
+ * Copyright 1988 by the Massachusetts Institute of Technology.
+ *
+ * For copying and distribution information, please see the file
+ * <mit-copyright.h>.
+ *
+ * Shared memory segment functions for session keys.  Derived from code
+ * contributed by Dan Kolkowitz (kolk@jessica.stanford.edu).
+ */
+
+#include "mit-copyright.h"
+
+#include <stdio.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#include "krb.h"
+#include "des.h"
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#define MAX_BUFF sizeof(des_cblock)*1000 /* room for 1k keys */
+
+extern int krb_debug;
+
+/*
+ * krb_create_shmtkt:
+ *
+ * create a shared memory segment for session keys, leaving its id
+ * in the specified filename.
+ */
+
+int
+krb_shm_create(file_name)
+char *file_name;
+{
+    int retval;
+    int shmid;
+    struct shmid_ds shm_buf;
+    FILE *sfile;
+    uid_t me, metoo, getuid(), geteuid();
+
+    (void) krb_shm_dest(file_name);	/* nuke it if it exists...
+					 this cleans up to make sure we
+					 don't slowly lose memory. */
+
+    shmid = shmget((long)IPC_PRIVATE,MAX_BUFF, IPC_CREAT);
+    if (shmid == -1) { 
+	if (krb_debug)
+	    perror("krb_shm_create shmget");
+	return(KFAILURE);		/* XXX */
+    }
+    me = getuid();
+    metoo = geteuid();
+    /* 
+     * now set up the buffer so that we can modify it 
+     */
+    shm_buf.shm_perm.uid = me;
+    shm_buf.shm_perm.gid = getgid();
+    shm_buf.shm_perm.mode = 0600;
+    if (shmctl(shmid,IPC_SET,&shm_buf) < 0) { /*can now map it */
+	if (krb_debug)
+	    perror("krb_shm_create shmctl");
+	(void) shmctl(shmid, IPC_RMID, 0);
+	return(KFAILURE);		/* XXX */
+    }
+#if !defined(_AIX)
+    (void) shmctl(shmid, SHM_LOCK, 0);	/* attempt to lock-in-core */
+#endif
+    /* arrange so the file is owned by the ruid
+       (swap real & effective uid if necessary). */
+    if (me != metoo) {
+	if (setreuid(metoo, me) < 0) {
+	    /* can't switch??? barf! */
+	    if (krb_debug)
+		perror("krb_shm_create: setreuid");
+	    (void) shmctl(shmid, IPC_RMID, 0);
+	    return(KFAILURE);
+	} else
+	    if (krb_debug)
+		printf("swapped UID's %d and %d\n",metoo,me);
+    }
+    if ((sfile = fopen(file_name,"w")) == 0) {
+	if (krb_debug)
+	    perror("krb_shm_create file");
+	(void) shmctl(shmid, IPC_RMID, 0);
+	return(KFAILURE);		/* XXX */
+    } 
+    if (fchmod(fileno(sfile),0600) < 0) {
+	if (krb_debug)
+	    perror("krb_shm_create fchmod");
+	(void) shmctl(shmid, IPC_RMID, 0);
+	return(KFAILURE);		/* XXX */
+    }	
+    if (me != metoo) {
+	if (setreuid(me, metoo) < 0) {
+	    /* can't switch??? barf! */
+	    if (krb_debug)
+		perror("krb_shm_create: setreuid2");
+	    (void) shmctl(shmid, IPC_RMID, 0);
+	    return(KFAILURE);
+	} else
+	    if (krb_debug)
+		printf("swapped UID's %d and %d\n",me,metoo);
+    }
+
+    (void) fprintf(sfile,"%d",shmid);
+    (void) fflush(sfile);
+    (void) fclose(sfile);
+    return(KSUCCESS);
+}
+
+
+/*
+ * krb_is_diskless:
+ *
+ * check / to see if file .diskless exists.  If so it is diskless.
+ *     Do it this way now to avoid dependencies on a particular routine.
+ *      Choose root file system since that will be private to the client.
+ */
+
+int krb_is_diskless()
+{
+	struct stat buf;
+	if (stat("/.diskless",&buf) < 0) 
+		return(0);
+	else return(1);
+}
+			
+/*
+ * krb_shm_dest: destroy shared memory segment with session keys, and remove
+ * file pointing to it.
+ */
+
+int krb_shm_dest(file)
+char *file;
+{
+    int shmid;
+    FILE *sfile;
+    struct stat st_buf;
+
+    if (stat(file,&st_buf) == 0) {
+	/* successful stat */
+	if ((sfile = fopen(file,"r")) == 0) {
+	    if (krb_debug)
+		perror("cannot open shared memory file");
+	    return(KFAILURE);		/* XXX */
+	}
+	if (fscanf(sfile,"%d",&shmid) == 1) {
+		if (shmctl(shmid,IPC_RMID,0) != 0) {
+		    if (krb_debug)
+			perror("krb_shm_dest: cannot delete shm segment");
+		    (void) fclose(sfile);
+		    return(KFAILURE);	/* XXX */
+		}		    
+	} else {
+	    if (krb_debug)
+		fprintf(stderr, "bad format in shmid file\n");
+	    (void) fclose(sfile);
+	    return(KFAILURE);		/* XXX */
+	}
+	(void) fclose(sfile);
+	(void) unlink(file);
+	return(KSUCCESS);
+    } else
+	return(RET_TKFIL);		/* XXX */
+}
+
+	
+