diff options
Diffstat (limited to 'crypto/kerberosIV/lib/kdb/krb_dbm.c')
| -rw-r--r-- | crypto/kerberosIV/lib/kdb/krb_dbm.c | 823 |
1 files changed, 0 insertions, 823 deletions
diff --git a/crypto/kerberosIV/lib/kdb/krb_dbm.c b/crypto/kerberosIV/lib/kdb/krb_dbm.c deleted file mode 100644 index 963656a87607..000000000000 --- a/crypto/kerberosIV/lib/kdb/krb_dbm.c +++ /dev/null @@ -1,823 +0,0 @@ -/* - Copyright (C) 1989 by the Massachusetts Institute of Technology - - Export of this software from the United States of America is assumed - to require a specific license from the United States Government. - It is the responsibility of any person or organization contemplating - export to obtain such a license before exporting. - -WITHIN THAT CONSTRAINT, permission to use, copy, modify, and -distribute this software and its documentation for any purpose and -without fee is hereby granted, provided that the above copyright -notice appear in all copies and that both that copyright notice and -this permission notice appear in supporting documentation, and that -the name of M.I.T. not be used in advertising or publicity pertaining -to distribution of the software without specific, written prior -permission. M.I.T. makes no representations about the suitability of -this software for any purpose. It is provided "as is" without express -or implied warranty. - - */ - -#include "kdb_locl.h" - -RCSID("$Id: krb_dbm.c,v 1.27 1997/05/02 14:29:09 assar Exp $"); - -#include <xdbm.h> - -#define KERB_DB_MAX_RETRY 5 - -#ifdef DEBUG -extern int debug; -extern long kerb_debug; -extern char *progname; -#endif - -static int init = 0; -static char default_db_name[] = DBM_FILE; -static char *current_db_name = default_db_name; - -static struct timeval timestamp;/* current time of request */ -static int non_blocking = 0; - -/* - * This module contains all of the code which directly interfaces to - * the underlying representation of the Kerberos database; this - * implementation uses a DBM or NDBM indexed "file" (actually - * implemented as two separate files) to store the relations, plus a - * third file as a semaphore to allow the database to be replaced out - * from underneath the KDC server. - */ - -/* - * Locking: - * - * There are two distinct locking protocols used. One is designed to - * lock against processes (the admin_server, for one) which make - * incremental changes to the database; the other is designed to lock - * against utilities (kdb_util, kpropd) which replace the entire - * database in one fell swoop. - * - * The first locking protocol is implemented using flock() in the - * krb_dbl_lock() and krb_dbl_unlock routines. - * - * The second locking protocol is necessary because DBM "files" are - * actually implemented as two separate files, and it is impossible to - * atomically rename two files simultaneously. It assumes that the - * database is replaced only very infrequently in comparison to the time - * needed to do a database read operation. - * - * A third file is used as a "version" semaphore; the modification - * time of this file is the "version number" of the database. - * At the start of a read operation, the reader checks the version - * number; at the end of the read operation, it checks again. If the - * version number changed, or if the semaphore was nonexistant at - * either time, the reader sleeps for a second to let things - * stabilize, and then tries again; if it does not succeed after - * KERB_DB_MAX_RETRY attempts, it gives up. - * - * On update, the semaphore file is deleted (if it exists) before any - * update takes place; at the end of the update, it is replaced, with - * a version number strictly greater than the version number which - * existed at the start of the update. - * - * If the system crashes in the middle of an update, the semaphore - * file is not automatically created on reboot; this is a feature, not - * a bug, since the database may be inconsistant. Note that the - * absence of a semaphore file does not prevent another _update_ from - * taking place later. Database replacements take place automatically - * only on slave servers; a crash in the middle of an update will be - * fixed by the next slave propagation. A crash in the middle of an - * update on the master would be somewhat more serious, but this would - * likely be noticed by an administrator, who could fix the problem and - * retry the operation. - */ - - -/* - * Utility routine: generate name of database file. - */ - -static char *gen_dbsuffix (char *db_name, char *sfx); - -static char * -gen_dbsuffix(char *db_name, char *sfx) -{ - char *dbsuffix; - - if (sfx == NULL) - sfx = ".ok"; - - asprintf (&dbsuffix, "%s%s", db_name, sfx); - return dbsuffix; -} - -static void -decode_princ_key (datum *key, char *name, char *instance); - -static void -decode_princ_key(datum *key, char *name, char *instance) -{ - strncpy(name, key->dptr, ANAME_SZ); - strncpy(instance, (char *)key->dptr + ANAME_SZ, INST_SZ); - name[ANAME_SZ - 1] = '\0'; - instance[INST_SZ - 1] = '\0'; -} - -static void -encode_princ_contents (datum *contents, Principal *principal); - -static void -encode_princ_contents(datum *contents, Principal *principal) -{ - contents->dsize = sizeof(*principal); - contents->dptr = (char *) principal; -} - -static void -decode_princ_contents (datum *contents, Principal *principal) -{ - memcpy(principal, contents->dptr, sizeof(*principal)); -} - -static void -encode_princ_key (datum *key, char *name, char *instance) -{ - static char keystring[ANAME_SZ + INST_SZ]; - - memset(keystring, 0, ANAME_SZ + INST_SZ); - strncpy(keystring, name, ANAME_SZ); - strncpy(&keystring[ANAME_SZ], instance, INST_SZ); - key->dptr = keystring; - key->dsize = ANAME_SZ + INST_SZ; -} - -static int dblfd = -1; /* db LOCK fd */ -static int mylock = 0; -static int inited = 0; - -static int -kerb_dbl_init (void); - -static int -kerb_dbl_init() -{ - if (!inited) { - char *filename = gen_dbsuffix (current_db_name, ".ok"); - if ((dblfd = open(filename, O_RDWR)) < 0) { - fprintf(stderr, "kerb_dbl_init: couldn't open %s\n", filename); - fflush(stderr); - perror("open"); - exit(1); - } - free(filename); - inited++; - } - return (0); -} - -static void -kerb_dbl_fini (void); - -static void -kerb_dbl_fini() -{ - close(dblfd); - dblfd = -1; - inited = 0; - mylock = 0; -} - -static int -kerb_dbl_lock (int mode); - -static int -kerb_dbl_lock(int mode) -{ - int flock_mode; - - if (!inited) - kerb_dbl_init(); - if (mylock) { /* Detect lock call when lock already - * locked */ - fprintf(stderr, "Kerberos locking error (mylock)\n"); - fflush(stderr); - exit(1); - } - switch (mode) { - case KERB_DBL_EXCLUSIVE: - flock_mode = K_LOCK_EX; - break; - case KERB_DBL_SHARED: - flock_mode = K_LOCK_SH; - break; - default: - fprintf(stderr, "invalid lock mode %d\n", mode); - abort(); - } - if (non_blocking) - flock_mode |= K_LOCK_NB; - - if (k_flock(dblfd, flock_mode) < 0) - return errno; - mylock++; - return 0; -} - -static void kerb_dbl_unlock (void); - -static void -kerb_dbl_unlock() -{ - if (!mylock) { /* lock already unlocked */ - fprintf(stderr, "Kerberos database lock not locked when unlocking.\n"); - fflush(stderr); - exit(1); - } - if (k_flock(dblfd, K_LOCK_UN) < 0) { - fprintf(stderr, "Kerberos database lock error. (unlocking)\n"); - fflush(stderr); - perror("k_flock"); - exit(1); - } - mylock = 0; -} - -int -kerb_db_set_lockmode (int mode); - -int -kerb_db_set_lockmode(int mode) -{ - int old = non_blocking; - non_blocking = mode; - return old; -} - -/* - * initialization for data base routines. - */ - -int -kerb_db_init (void); - -int -kerb_db_init() -{ - init = 1; - return (0); -} - -/* - * gracefully shut down database--must be called by ANY program that does - * a kerb_db_init - */ - -void -kerb_db_fini (void); - -void -kerb_db_fini() -{ -} - -/* - * Set the "name" of the current database to some alternate value. - * - * Passing a null pointer as "name" will set back to the default. - * If the alternate database doesn't exist, nothing is changed. - */ - -int -kerb_db_set_name (char *name); - -int -kerb_db_set_name(char *name) -{ - DBM *db; - - if (name == NULL) - name = default_db_name; - db = dbm_open(name, 0, 0); - if (db == NULL) - return errno; - dbm_close(db); - kerb_dbl_fini(); - current_db_name = name; - return 0; -} - -/* - * Return the last modification time of the database. - */ - -time_t -kerb_get_db_age (void); - -time_t -kerb_get_db_age() -{ - struct stat st; - char *okname; - time_t age; - - okname = gen_dbsuffix(current_db_name, ".ok"); - - if (stat (okname, &st) < 0) - age = 0; - else - age = st.st_mtime; - - free (okname); - return age; -} - -/* - * Remove the semaphore file; indicates that database is currently - * under renovation. - * - * This is only for use when moving the database out from underneath - * the server (for example, during slave updates). - */ - -static time_t -kerb_start_update (char *db_name); - -static time_t -kerb_start_update(char *db_name) -{ - char *okname = gen_dbsuffix(db_name, ".ok"); - time_t age = kerb_get_db_age(); - - if (unlink(okname) < 0 - && errno != ENOENT) { - age = -1; - } - free (okname); - return age; -} - -static int -kerb_end_update (char *db_name, time_t age); - -static int -kerb_end_update(char *db_name, time_t age) -{ - int fd; - int retval = 0; - char *new_okname = gen_dbsuffix(db_name, ".ok#"); - char *okname = gen_dbsuffix(db_name, ".ok"); - - fd = open (new_okname, O_CREAT|O_RDWR|O_TRUNC, 0600); - if (fd < 0) - retval = errno; - else { - struct stat st; - struct utimbuf tv; - /* make sure that semaphore is "after" previous value. */ - if (fstat (fd, &st) == 0 - && st.st_mtime <= age) { - tv.actime = st.st_atime; - tv.modtime = age; - /* set times.. */ - utime (new_okname, &tv); - fsync(fd); - } - close(fd); - if (rename (new_okname, okname) < 0) - retval = errno; - } - - free (new_okname); - free (okname); - - return retval; -} - -static time_t -kerb_start_read (void); - -static time_t -kerb_start_read() -{ - return kerb_get_db_age(); -} - -static int kerb_end_read (time_t age); - -static int -kerb_end_read(time_t age) -{ - if (kerb_get_db_age() != age || age == -1) { - return -1; - } - return 0; -} - -/* - * Create the database, assuming it's not there. - */ -int -kerb_db_create(char *db_name) -{ - char *okname = gen_dbsuffix(db_name, ".ok"); - int fd; - int ret = 0; -#ifdef NDBM - DBM *db; - - db = dbm_open(db_name, O_RDWR|O_CREAT|O_EXCL, 0600); - if (db == NULL) - ret = errno; - else - dbm_close(db); -#else - char *dirname = gen_dbsuffix(db_name, ".dir"); - char *pagname = gen_dbsuffix(db_name, ".pag"); - - fd = open(dirname, O_RDWR|O_CREAT|O_EXCL, 0600); - if (fd < 0) - ret = errno; - else { - close(fd); - fd = open (pagname, O_RDWR|O_CREAT|O_EXCL, 0600); - if (fd < 0) - ret = errno; - else - close(fd); - } - if (dbminit(db_name) < 0) - ret = errno; -#endif - if (ret == 0) { - fd = open (okname, O_CREAT|O_RDWR|O_TRUNC, 0600); - if (fd < 0) - ret = errno; - close(fd); - } - return ret; -} - -/* - * "Atomically" rename the database in a way that locks out read - * access in the middle of the rename. - * - * Not perfect; if we crash in the middle of an update, we don't - * necessarily know to complete the transaction the rename, but... - */ - -int -kerb_db_rename(char *from, char *to) -{ -#ifdef HAVE_NEW_DB - char *fromdb = gen_dbsuffix (from, ".db"); - char *todb = gen_dbsuffix (to, ".db"); -#else - char *fromdir = gen_dbsuffix (from, ".dir"); - char *todir = gen_dbsuffix (to, ".dir"); - char *frompag = gen_dbsuffix (from , ".pag"); - char *topag = gen_dbsuffix (to, ".pag"); -#endif - char *fromok = gen_dbsuffix(from, ".ok"); - long trans = kerb_start_update(to); - int ok = 0; - -#ifdef HAVE_NEW_DB - if (rename (fromdb, todb) == 0) { - unlink (fromok); - ok = 1; - } - free (fromdb); - free (todb); -#else - if ((rename (fromdir, todir) == 0) - && (rename (frompag, topag) == 0)) { - unlink (fromok); - ok = 1; - } - free (fromdir); - free (todir); - free (frompag); - free (topag); -#endif - free (fromok); - if (ok) - return kerb_end_update(to, trans); - else - return -1; -} - -int -kerb_db_delete_principal (char *name, char *inst) -{ - DBM *db; - int try; - int done = 0; - int code; - datum key; - - if(!init) - kerb_db_init(); - - for(try = 0; try < KERB_DB_MAX_RETRY; try++){ - if((code = kerb_dbl_lock(KERB_DBL_SHARED)) != 0) - return -1; - - db = dbm_open(current_db_name, O_RDWR, 0600); - if(db == NULL) - return -1; - encode_princ_key(&key, name, inst); - if(dbm_delete(db, key) == 0) - done = 1; - - dbm_close(db); - kerb_dbl_unlock(); - if(done) - break; - if(!non_blocking) - sleep(1); - } - if(!done) - return -1; - return 0; -} - - -/* - * look up a principal in the data base returns number of principals - * found , and whether there were more than requested. - */ - -int -kerb_db_get_principal (char *name, char *inst, Principal *principal, - unsigned int max, int *more) -{ - int found = 0, code; - int wildp, wildi; - datum key, contents; - char testname[ANAME_SZ], testinst[INST_SZ]; - u_long trans; - int try; - DBM *db; - - if (!init) - kerb_db_init(); /* initialize database routines */ - - for (try = 0; try < KERB_DB_MAX_RETRY; try++) { - trans = kerb_start_read(); - - if ((code = kerb_dbl_lock(KERB_DBL_SHARED)) != 0) - return -1; - - db = dbm_open(current_db_name, O_RDONLY, 0600); - - *more = 0; - -#ifdef DEBUG - if (kerb_debug & 2) - fprintf(stderr, - "%s: db_get_principal for %s %s max = %d", - progname, name, inst, max); -#endif - - wildp = !strcmp(name, "*"); - wildi = !strcmp(inst, "*"); - - if (!wildi && !wildp) { /* nothing's wild */ - encode_princ_key(&key, name, inst); - contents = dbm_fetch(db, key); - if (contents.dptr == NULL) { - found = 0; - goto done; - } - decode_princ_contents(&contents, principal); -#ifdef DEBUG - if (kerb_debug & 1) { - fprintf(stderr, "\t found %s %s p_n length %d t_n length %d\n", - principal->name, principal->instance, - strlen(principal->name), - strlen(principal->instance)); - } -#endif - found = 1; - goto done; - } - /* process wild cards by looping through entire database */ - - for (key = dbm_firstkey(db); key.dptr != NULL; - key = dbm_next(db, key)) { - decode_princ_key(&key, testname, testinst); - if ((wildp || !strcmp(testname, name)) && - (wildi || !strcmp(testinst, inst))) { /* have a match */ - if (found >= max) { - *more = 1; - goto done; - } else { - found++; - contents = dbm_fetch(db, key); - decode_princ_contents(&contents, principal); -#ifdef DEBUG - if (kerb_debug & 1) { - fprintf(stderr, - "\tfound %s %s p_n length %d t_n length %d\n", - principal->name, principal->instance, - strlen(principal->name), - strlen(principal->instance)); - } -#endif - principal++; /* point to next */ - } - } - } - - done: - kerb_dbl_unlock(); /* unlock read lock */ - dbm_close(db); - if (kerb_end_read(trans) == 0) - break; - found = -1; - if (!non_blocking) - sleep(1); - } - return (found); -} - -/* Use long * rather than DBM * so that the database structure is private */ - -long * -kerb_db_begin_update(void) -{ - int code; - - gettimeofday(×tamp, NULL); - - if (!init) - kerb_db_init(); - - if ((code = kerb_dbl_lock(KERB_DBL_EXCLUSIVE)) != 0) - return 0; - - return (long *) dbm_open(current_db_name, O_RDWR, 0600); -} - -void -kerb_db_end_update(long *db) -{ - dbm_close((DBM *)db); - kerb_dbl_unlock(); /* unlock database */ -} - -int -kerb_db_update(long *db, Principal *principal, unsigned int max) -{ - int found = 0; - u_long i; - datum key, contents; - -#ifdef DEBUG - if (kerb_debug & 2) - fprintf(stderr, "%s: kerb_db_put_principal max = %d", - progname, max); -#endif - - /* for each one, stuff temps, and do replace/append */ - for (i = 0; i < max; i++) { - encode_princ_contents(&contents, principal); - encode_princ_key(&key, principal->name, principal->instance); - dbm_store((DBM *)db, key, contents, DBM_REPLACE); -#ifdef DEBUG - if (kerb_debug & 1) { - fprintf(stderr, "\n put %s %s\n", - principal->name, principal->instance); - } -#endif - found++; - principal++; /* bump to next struct */ - } - return found; -} - -/* - * Update a name in the data base. Returns number of names - * successfully updated. - */ - -int -kerb_db_put_principal (Principal *principal, unsigned int max); - -int -kerb_db_put_principal(Principal *principal, - unsigned max) - -{ - int found; - long *db; - - db = kerb_db_begin_update(); - if (db == 0) - return -1; - - found = kerb_db_update(db, principal, max); - - kerb_db_end_update(db); - return (found); -} - -void -kerb_db_get_stat (DB_stat *s); - -void -kerb_db_get_stat(DB_stat *s) -{ - gettimeofday(×tamp, NULL); - - s->cpu = 0; - s->elapsed = 0; - s->dio = 0; - s->pfault = 0; - s->t_stamp = timestamp.tv_sec; - s->n_retrieve = 0; - s->n_replace = 0; - s->n_append = 0; - s->n_get_stat = 0; - s->n_put_stat = 0; - /* update local copy too */ -} - -void -kerb_db_put_stat (DB_stat *s); - -void -kerb_db_put_stat(DB_stat *s) -{ -} - -void -delta_stat (DB_stat *a, DB_stat *b, DB_stat *c); - -void -delta_stat(DB_stat *a, DB_stat *b, DB_stat *c) -{ - /* c = a - b then b = a for the next time */ - - c->cpu = a->cpu - b->cpu; - c->elapsed = a->elapsed - b->elapsed; - c->dio = a->dio - b->dio; - c->pfault = a->pfault - b->pfault; - c->t_stamp = a->t_stamp - b->t_stamp; - c->n_retrieve = a->n_retrieve - b->n_retrieve; - c->n_replace = a->n_replace - b->n_replace; - c->n_append = a->n_append - b->n_append; - c->n_get_stat = a->n_get_stat - b->n_get_stat; - c->n_put_stat = a->n_put_stat - b->n_put_stat; - - memcpy(b, a, sizeof(DB_stat)); - return; -} - -/* - * look up a dba in the data base returns number of dbas found , and - * whether there were more than requested. - */ - -int -kerb_db_get_dba (char *dba_name, char *dba_inst, Dba *dba, unsigned int max, int *more); - -int -kerb_db_get_dba(char *dba_name, char *dba_inst, Dba *dba, - unsigned max, - int *more) - /* could have wild card */ - /* could have wild card */ - /* max number of name structs to return */ - /* where there more than 'max' tuples? */ -{ - *more = 0; - return (0); -} - -int -kerb_db_iterate (k_iter_proc_t func, void *arg) -{ - datum key, contents; - Principal *principal; - int code; - DBM *db; - - kerb_db_init(); /* initialize and open the database */ - if ((code = kerb_dbl_lock(KERB_DBL_SHARED)) != 0) - return code; - - db = dbm_open(current_db_name, O_RDONLY, 0600); - - for (key = dbm_firstkey (db); key.dptr != NULL; key = dbm_next(db, key)) { - contents = dbm_fetch (db, key); - /* XXX may not be properly aligned */ - principal = (Principal *) contents.dptr; - if ((code = (*func)(arg, principal)) != 0) - return code; - } - dbm_close(db); - kerb_dbl_unlock(); - return 0; -} |