1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #if defined(LIBC_SCCS) && !defined(lint) 31 static char rcsid[] = "$OpenBSD: pwcache.c,v 1.6 2003/06/02 20:18:34 millert Exp $"; 32 #endif /* LIBC_SCCS and not lint */ 33 34 #include <sys/types.h> 35 36 #include <grp.h> 37 #include <pwd.h> 38 #include <stdio.h> 39 #include <string.h> 40 41 #define NCACHE 64 /* power of 2 */ 42 #define MASK (NCACHE - 1) /* bits to store with */ 43 44 char * 45 user_from_uid(uid, nouser) 46 uid_t uid; 47 int nouser; 48 { 49 static struct ncache { 50 uid_t uid; 51 char name[_PW_NAME_LEN + 1]; 52 } c_uid[NCACHE]; 53 static int pwopen; 54 static char nbuf[15]; /* 32 bits == 10 digits */ 55 register struct passwd *pw; 56 register struct ncache *cp; 57 58 cp = c_uid + (uid & MASK); 59 if (cp->uid != uid || !*cp->name) { 60 if (pwopen == 0) { 61 setpassent(1); 62 pwopen = 1; 63 } 64 if ((pw = getpwuid(uid)) == NULL) { 65 if (nouser) 66 return (NULL); 67 (void)snprintf(nbuf, sizeof(nbuf), "%u", uid); 68 return (nbuf); 69 } 70 cp->uid = uid; 71 strlcpy(cp->name, pw->pw_name, sizeof(cp->name)); 72 } 73 return (cp->name); 74 } 75 76 char * 77 group_from_gid(gid, nogroup) 78 gid_t gid; 79 int nogroup; 80 { 81 static struct ncache { 82 gid_t gid; 83 char name[_PW_NAME_LEN + 1]; 84 } c_gid[NCACHE]; 85 static int gropen; 86 static char nbuf[15]; /* 32 bits == 10 digits */ 87 struct group *gr; 88 struct ncache *cp; 89 90 cp = c_gid + (gid & MASK); 91 if (cp->gid != gid || !*cp->name) { 92 if (gropen == 0) { 93 setgroupent(1); 94 gropen = 1; 95 } 96 if ((gr = getgrgid(gid)) == NULL) { 97 if (nogroup) 98 return (NULL); 99 (void)snprintf(nbuf, sizeof(nbuf), "%u", gid); 100 return (nbuf); 101 } 102 cp->gid = gid; 103 strlcpy(cp->name, gr->gr_name, sizeof(cp->name)); 104 } 105 return (cp->name); 106 } 107