1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 26 /* All Rights Reserved */ 27 28 29 #pragma ident "%Z%%M% %I% %E% SMI" /* SVr4.0 1.5 */ 30 31 #include <sys/types.h> 32 #include <stdio.h> 33 #include <userdefs.h> 34 35 #include <sys/param.h> 36 #ifndef MAXUID 37 #include <limits.h> 38 #ifdef UID_MAX 39 #define MAXUID UID_MAX 40 #else 41 #define MAXUID 60000 42 #endif 43 #endif 44 45 /* 46 * Check to see that the gid is not a reserved gid 47 * -- nobody, noaccess or nogroup 48 */ 49 static int 50 isvalidgid(gid_t gid) 51 { 52 return (gid != 60001 && gid != 60002 && gid != 65534); 53 } 54 55 gid_t 56 findnextgid() 57 { 58 FILE *fptr; 59 gid_t last, next; 60 gid_t gid; 61 62 /* 63 * Sort the used GIDs in decreasing order to return MAXUSED + 1 64 */ 65 if ((fptr = popen("exec sh -c " 66 "\"getent group|cut -f3 -d:|sort -nr|uniq \" 2>/dev/null", 67 "r")) == NULL) 68 return (-1); 69 70 if (fscanf(fptr, "%u\n", &next) == EOF) { 71 (void) pclose(fptr); 72 return (DEFRID + 1); 73 } 74 75 /* 76 * 'next' is now the highest allocated gid. 77 * 78 * The simplest allocation is where we just add one, and obtain 79 * a valid gid. If this fails look for a hole in the gid range .. 80 */ 81 82 last = MAXUID; /* upper limit */ 83 gid = -1; /* start invalid */ 84 do { 85 if (!isvalidgid(next)) 86 continue; 87 88 if (next <= DEFRID) { 89 if (last != DEFRID + 1) 90 gid = DEFRID + 1; 91 break; 92 } 93 94 if ((gid = next + 1) != last) { 95 while (!isvalidgid(gid)) 96 gid++; 97 if (gid > 0 && gid < last) 98 break; 99 } 100 101 gid = -1; 102 last = next; 103 104 } while (fscanf(fptr, "%u\n", &next) != EOF); 105 106 (void) pclose(fptr); 107 108 return (gid); 109 }