this commit includes all the changes on the OV_9510_INTEGRATION and

OV_MERGE branches.  This includes, but is not limited to, the new openvision
admin system, and major changes to gssapi to add functionality, and bring
the implementation in line with rfc1964.  before committing, the
code was built and tested for netbsd and solaris.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@8774 dc483132-0cff-0310-8789-dd5450dbe970

1 files changed, 536 insertions, 0 deletions

diff --git a/src/kadmin/v4server/acl_files.c b/src/kadmin/v4server/acl_files.c
new file mode 100644
index 000000000..ae3b0c6bf
--- /dev/null
+++ b/src/kadmin/v4server/acl_files.c
@@ -0,0 +1,536 @@
+/*
+ *	kadmin/v4server/acl_files.c
+ *
+ * Copyright 1987,1989 by the Massachusetts Institute of Technology.
+ *
+ * For copying and distribution information, please see the file
+ * <mit-copyright.h>.
+ *
+ */
+
+
+/*** Routines for manipulating access control list files ***/
+
+#include <stdio.h>
+#include <string.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <sys/types.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <sys/errno.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include "krb.h"
+
+#ifndef KRB_REALM
+#define KRB_REALM	"ATHENA.MIT.EDU"
+#endif
+
+/* "aname.inst@realm" */
+#define MAX_PRINCIPAL_SIZE  (ANAME_SZ + INST_SZ + REALM_SZ + 3)
+#define INST_SEP '.'
+#define REALM_SEP '@'
+
+#define LINESIZE 2048		/* Maximum line length in an acl file */
+
+#define NEW_FILE "%s.~NEWACL~"	/* Format for name of altered acl file */
+#define WAIT_TIME 300		/* Maximum time allowed write acl file */
+
+#define CACHED_ACLS 8		/* How many acls to cache */
+				/* Each acl costs 1 open file descriptor */
+#define ACL_LEN 16		/* Twice a reasonable acl length */
+
+#define MAX(a,b) (((a)>(b))?(a):(b))
+#define MIN(a,b) (((a)<(b))?(a):(b))
+
+#define COR(a,b) ((a!=NULL)?(a):(b))
+
+extern int errno;
+
+extern char *malloc(), *calloc();
+extern time_t time();
+
+static int acl_abort();
+
+/* Canonicalize a principal name */
+/* If instance is missing, it becomes "" */
+/* If realm is missing, it becomes the local realm */
+/* Canonicalized form is put in canon, which must be big enough to hold
+   MAX_PRINCIPAL_SIZE characters */
+void acl_canonicalize_principal(principal, canon)
+char *principal;
+char *canon;
+{
+    char *dot, *atsign, *end;
+    int len;
+
+    dot = strchr(principal, INST_SEP);
+    atsign = strchr(principal, REALM_SEP);
+
+    /* Maybe we're done already */
+    if(dot != NULL && atsign != NULL) {
+	if(dot < atsign) {
+	    /* It's for real */
+	    /* Copy into canon */
+	    strncpy(canon, principal, MAX_PRINCIPAL_SIZE);
+	    canon[MAX_PRINCIPAL_SIZE-1] = '\0';
+	    return;
+	} else {
+	    /* Nope, it's part of the realm */
+	    dot = NULL;
+	}
+    }
+    
+    /* No such luck */
+    end = principal + strlen(principal);
+
+    /* Get the principal name */
+    len = MIN(ANAME_SZ, COR(dot, COR(atsign, end)) - principal);
+    strncpy(canon, principal, len);
+    canon += len;
+
+    /* Add INST_SEP */
+    *canon++ = INST_SEP;
+
+    /* Get the instance, if it exists */
+    if(dot != NULL) {
+	++dot;
+	len = MIN(INST_SZ, COR(atsign, end) - dot);
+	strncpy(canon, dot, len);
+	canon += len;
+    }
+
+    /* Add REALM_SEP */
+    *canon++ = REALM_SEP;
+
+    /* Get the realm, if it exists */
+    /* Otherwise, default to local realm */
+    if(atsign != NULL) {
+	++atsign;
+	len = MIN(REALM_SZ, end - atsign);
+	strncpy(canon, atsign, len);
+	canon += len;
+	*canon++ = '\0';
+    } else if(krb_get_lrealm(canon, 1) != KSUCCESS) {
+	strcpy(canon, KRB_REALM);
+    }
+}
+	    
+/* Get a lock to modify acl_file */
+/* Return new FILE pointer */
+/* or NULL if file cannot be modified */
+/* REQUIRES WRITE PERMISSION TO CONTAINING DIRECTORY */
+static FILE *acl_lock_file(acl_file)
+char *acl_file;
+{
+    struct stat s;
+    char new[LINESIZE];
+    int nfd;
+    FILE *nf;
+    int mode;
+
+    if(stat(acl_file, &s) < 0) return(NULL);
+    mode = s.st_mode;
+    sprintf(new, NEW_FILE, acl_file);
+    for(;;) {
+	/* Open the new file */
+	if((nfd = open(new, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0) {
+	    if(errno == EEXIST) {
+		/* Maybe somebody got here already, maybe it's just old */
+		if(stat(new, &s) < 0) return(NULL);
+		if(time(0) - s.st_ctime > WAIT_TIME) {
+		    /* File is stale, kill it */
+		    unlink(new);
+		    continue;
+		} else {
+		    /* Wait and try again */
+		    sleep(1);
+		    continue;
+		}
+	    } else {
+		/* Some other error, we lose */
+		return(NULL);
+	    }
+	}
+
+	/* If we got to here, the lock file is ours and ok */
+	/* Reopen it under stdio */
+	if((nf = fdopen(nfd, "w")) == NULL) {
+	    /* Oops, clean up */
+	    unlink(new);
+	}
+	return(nf);
+    }
+}
+
+/* Commit changes to acl_file written onto FILE *f */
+/* Returns zero if successful */
+/* Returns > 0 if lock was broken */
+/* Returns < 0 if some other error occurs */
+/* Closes f */
+static int acl_commit(acl_file, f)
+char *acl_file;
+FILE *f;     
+{
+    char new[LINESIZE];
+    int ret;
+    struct stat s;
+
+    sprintf(new, NEW_FILE, acl_file);
+    if(fflush(f) < 0
+       || fstat(fileno(f), &s) < 0
+       || s.st_nlink == 0) {
+	acl_abort(acl_file, f);
+	return(-1);
+    }
+
+    ret = rename(new, acl_file);
+    fclose(f);
+    return(ret);
+}
+
+/* Abort changes to acl_file written onto FILE *f */
+/* Returns 0 if successful, < 0 otherwise */
+/* Closes f */
+static int acl_abort(acl_file, f)
+char *acl_file;
+FILE *f;     
+{
+    char new[LINESIZE];
+    int ret;
+    struct stat s;
+
+    /* make sure we aren't nuking someone else's file */
+    if(fstat(fileno(f), &s) < 0
+       || s.st_nlink == 0) {
+	   fclose(f);
+	   return(-1);
+       } else {
+	   sprintf(new, NEW_FILE, acl_file);
+	   ret = unlink(new);
+	   fclose(f);
+	   return(ret);
+       }
+}
+
+/* Initialize an acl_file */
+/* Creates the file with permissions perm if it does not exist */
+/* Erases it if it does */
+/* Returns return value of acl_commit */
+int acl_initialize(acl_file, perm)
+char *acl_file;
+int perm;
+{
+    FILE *new;
+    int fd;
+
+    /* Check if the file exists already */
+    if((new = acl_lock_file(acl_file)) != NULL) {
+	return(acl_commit(acl_file, new));
+    } else {
+	/* File must be readable and writable by owner */
+	if((fd = open(acl_file, O_CREAT|O_EXCL, perm|0600)) < 0) {
+	    return(-1);
+	} else {
+	    close(fd);
+	    return(0);
+	}
+    }
+}
+
+/* Eliminate all whitespace character in buf */
+/* Modifies its argument */
+static nuke_whitespace(buf)
+char *buf;
+{
+    register char *pin, *pout;
+
+    for(pin = pout = buf; *pin != '\0'; pin++)
+	if(!isspace(*pin)) *pout++ = *pin;
+    *pout = '\0';		/* Terminate the string */
+}
+
+/* Hash table stuff */
+
+struct hashtbl {
+    int size;			/* Max number of entries */
+    int entries;		/* Actual number of entries */
+    char **tbl;			/* Pointer to start of table */
+};
+
+/* Make an empty hash table of size s */
+static struct hashtbl *make_hash(size)
+int size;
+{
+    struct hashtbl *h;
+
+    if(size < 1) size = 1;
+    h = (struct hashtbl *) malloc(sizeof(struct hashtbl));
+    h->size = size;
+    h->entries = 0;
+    h->tbl = (char **) calloc(size, sizeof(char *));
+    return(h);
+}
+
+/* Destroy a hash table */
+static destroy_hash(h)
+struct hashtbl *h;
+{
+    int i;
+
+    for(i = 0; i < h->size; i++) {
+	if(h->tbl[i] != NULL) free(h->tbl[i]);
+    }
+    free(h->tbl);
+    free(h);
+}
+
+/* Compute hash value for a string */
+static unsigned hashval(s)
+register char *s;
+{
+    register unsigned hv;
+
+    for(hv = 0; *s != '\0'; s++) {
+	hv ^= ((hv << 3) ^ *s);
+    }
+    return(hv);
+}
+
+/* Add an element to a hash table */
+static add_hash(h, el)
+struct hashtbl *h;
+char *el;
+{
+    unsigned hv;
+    char *s;
+    char **old;
+    int i;
+
+    /* Make space if it isn't there already */
+    if(h->entries + 1 > (h->size >> 1)) {
+	old = h->tbl;
+	h->tbl = (char **) calloc(h->size << 1, sizeof(char *));
+	for(i = 0; i < h->size; i++) {
+	    if(old[i] != NULL) {
+		hv = hashval(old[i]) % (h->size << 1);
+		while(h->tbl[hv] != NULL) hv = (hv+1) % (h->size << 1);
+		h->tbl[hv] = old[i];
+	    }
+	}
+	h->size = h->size << 1;
+	free(old);
+    }
+
+    hv = hashval(el) % h->size;
+    while(h->tbl[hv] != NULL && strcmp(h->tbl[hv], el)) hv = (hv+1) % h->size;
+    s = malloc(strlen(el)+1);
+    strcpy(s, el);
+    h->tbl[hv] = s;
+    h->entries++;
+}
+
+/* Returns nonzero if el is in h */
+static check_hash(h, el)
+struct hashtbl *h;
+char *el;
+{
+    unsigned hv;
+
+    for(hv = hashval(el) % h->size;
+	h->tbl[hv] != NULL;
+	hv = (hv + 1) % h->size) {
+	    if(!strcmp(h->tbl[hv], el)) return(1);
+	}
+    return(0);
+}
+
+struct acl {
+    char filename[LINESIZE];	/* Name of acl file */
+    int fd;			/* File descriptor for acl file */
+    struct stat status;		/* File status at last read */
+    struct hashtbl *acl;	/* Acl entries */
+};
+
+static struct acl acl_cache[CACHED_ACLS];
+
+static int acl_cache_count = 0;
+static int acl_cache_next = 0;
+
+/* Returns < 0 if unsuccessful in loading acl */
+/* Returns index into acl_cache otherwise */
+/* Note that if acl is already loaded, this is just a lookup */
+static int acl_load(name)
+char *name;
+{
+    int i;
+    FILE *f;
+    struct stat s;
+    char buf[MAX_PRINCIPAL_SIZE];
+    char canon[MAX_PRINCIPAL_SIZE];
+
+    /* See if it's there already */
+    for(i = 0; i < acl_cache_count; i++) {
+	if(!strcmp(acl_cache[i].filename, name)
+	   && acl_cache[i].fd >= 0) goto got_it;
+    }
+
+    /* It isn't, load it in */
+    /* maybe there's still room */
+    if(acl_cache_count < CACHED_ACLS) {
+	i = acl_cache_count++;
+    } else {
+	/* No room, clean one out */
+	i = acl_cache_next;
+	acl_cache_next = (acl_cache_next + 1) % CACHED_ACLS;
+	close(acl_cache[i].fd);
+	if(acl_cache[i].acl) {
+	    destroy_hash(acl_cache[i].acl);
+	    acl_cache[i].acl = (struct hashtbl *) 0;
+	}
+    }
+
+    /* Set up the acl */
+    strcpy(acl_cache[i].filename, name);
+    if((acl_cache[i].fd = open(name, O_RDONLY, 0)) < 0) return(-1);
+    /* Force reload */
+    acl_cache[i].acl = (struct hashtbl *) 0;
+
+ got_it:
+    /*
+     * See if the stat matches
+     *
+     * Use stat(), not fstat(), as the file may have been re-created by
+     * acl_add or acl_delete.  If this happens, the old inode will have
+     * no changes in the mod-time and the following test will fail.
+     */
+    if(stat(acl_cache[i].filename, &s) < 0) return(-1);
+    if(acl_cache[i].acl == (struct hashtbl *) 0
+       || s.st_nlink != acl_cache[i].status.st_nlink
+       || s.st_mtime != acl_cache[i].status.st_mtime
+       || s.st_ctime != acl_cache[i].status.st_ctime) {
+	   /* Gotta reload */
+	   if(acl_cache[i].fd >= 0) close(acl_cache[i].fd);
+	   if((acl_cache[i].fd = open(name, O_RDONLY, 0)) < 0) return(-1);
+	   if((f = fdopen(acl_cache[i].fd, "r")) == NULL) return(-1);
+	   if(acl_cache[i].acl) destroy_hash(acl_cache[i].acl);
+	   acl_cache[i].acl = make_hash(ACL_LEN);
+	   while(fgets(buf, sizeof(buf), f) != NULL) {
+	       nuke_whitespace(buf);
+	       acl_canonicalize_principal(buf, canon);
+	       add_hash(acl_cache[i].acl, canon);
+	   }
+	   fclose(f);
+	   acl_cache[i].status = s;
+       }
+    return(i);
+}
+
+/* Returns nonzero if it can be determined that acl contains principal */
+/* Principal is not canonicalized, and no wildcarding is done */
+acl_exact_match(acl, principal)
+char *acl;
+char *principal;
+{
+    int idx;
+
+    return((idx = acl_load(acl)) >= 0
+	   && check_hash(acl_cache[idx].acl, principal));
+}
+
+/* Returns nonzero if it can be determined that acl contains principal */
+/* Recognizes wildcards in acl of the form
+   name.*@realm, *.*@realm, and *.*@* */
+acl_check(acl, principal)
+char *acl;
+char *principal;
+{
+    char buf[MAX_PRINCIPAL_SIZE];
+    char canon[MAX_PRINCIPAL_SIZE];
+    char *realm, *tmp;
+
+    acl_canonicalize_principal(principal, canon);
+
+    /* Is it there? */
+    if(acl_exact_match(acl, canon)) return(1);
+
+    /* Try the wildcards */
+    realm = strchr(canon, REALM_SEP);
+    tmp = strchr(canon, INST_SEP);
+    *tmp = '\0';			/* Chuck the instance */
+
+    sprintf(buf, "%s.*%s", canon, realm);
+    if(acl_exact_match(acl, buf)) return(1);
+
+    sprintf(buf, "*.*%s", realm);
+    if(acl_exact_match(acl, buf) || acl_exact_match(acl, "*.*@*")) return(1);
+       
+    return(0);
+}
+
+/* Adds principal to acl */
+/* Wildcards are interpreted literally */
+acl_add(acl, principal)
+char *acl;
+char *principal;
+{
+    int idx;
+    int i;
+    FILE *new;
+    char canon[MAX_PRINCIPAL_SIZE];
+
+    acl_canonicalize_principal(principal, canon);
+
+    if((new = acl_lock_file(acl)) == NULL) return(-1);
+    if((acl_exact_match(acl, canon))
+       || (idx = acl_load(acl)) < 0) {
+	   acl_abort(acl, new);
+	   return(-1);
+       }
+    /* It isn't there yet, copy the file and put it in */
+    for(i = 0; i < acl_cache[idx].acl->size; i++) {
+	if(acl_cache[idx].acl->tbl[i] != NULL) {
+	    if(fputs(acl_cache[idx].acl->tbl[i], new) == EOF
+	       || putc('\n', new) != '\n') {
+		   acl_abort(acl, new);
+		   return(-1);
+	       }
+	}
+    }
+    fputs(canon, new);
+    putc('\n', new);
+    return(acl_commit(acl, new));
+}
+
+/* Removes principal from acl */
+/* Wildcards are interpreted literally */
+acl_delete(acl, principal)
+char *acl;
+char *principal;
+{
+    int idx;
+    int i;
+    FILE *new;
+    char canon[MAX_PRINCIPAL_SIZE];
+
+    acl_canonicalize_principal(principal, canon);
+
+    if((new = acl_lock_file(acl)) == NULL) return(-1);
+    if((!acl_exact_match(acl, canon))
+       || (idx = acl_load(acl)) < 0) {
+	   acl_abort(acl, new);
+	   return(-1);
+       }
+    /* It isn't there yet, copy the file and put it in */
+    for(i = 0; i < acl_cache[idx].acl->size; i++) {
+	if(acl_cache[idx].acl->tbl[i] != NULL
+	   && strcmp(acl_cache[idx].acl->tbl[i], canon)) {
+	       fputs(acl_cache[idx].acl->tbl[i], new);
+	       putc('\n', new);
+	}
+    }
+    return(acl_commit(acl, new));
+}
+