1/* 2 * Copyright (c) 2011 Apple Inc. All rights reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. Please obtain a copy of the License at 10 * http://www.opensource.apple.com/apsl/ and read it before using this 11 * file. 12 * 13 * The Original Code and all software distributed under the License are 14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 18 * Please see the License for the specific language governing rights and 19 * limitations under the License. 20 * 21 * @APPLE_LICENSE_HEADER_END@ 22 */ 23 24#include <stdio.h> 25#include <string.h> 26#include <errno.h> 27#include <sys/types.h> 28#include <unistd.h> 29 30#include <SMBClient/smbclient.h> 31#include <SMBClient/smbclient_internal.h> 32 33/* 34 * This is a bit ugly. 35 * 36 * We're doing this in a subprocess so that we run in the audit 37 * session that the kernel asked automountd to use. 38 * 39 * However, we need to be passed a Rodent Of Unusual Size, err, umm, a 40 * blob of variable size to pass to the SMBRemountServer call. That's 41 * a bit ugly to pass on the command line, so we do it over a pipe. 42 * 43 * The first thing we read from the pipe is a big-endian 4-byte byte 44 * count. Then we allocate a buffer and read the rest of the data 45 * into that. 46 */ 47int 48main() 49{ 50 ssize_t bytes_read; 51 uint32_t byte_count; 52 void *blob; 53 int child_pid; 54 int status; 55 56 /* 57 * Read the byte count. 58 */ 59 bytes_read = read(0, &byte_count, sizeof byte_count); 60 if (bytes_read == -1) { 61 fprintf(stderr, "smbremountserver: Error reading byte count: %s\n", 62 strerror(errno)); 63 return 2; 64 } 65 if (bytes_read < 0 || (size_t)bytes_read != sizeof byte_count) { 66 fprintf(stderr, "smbremountserver: Read only %zd bytes of byte count\n", 67 bytes_read); 68 return 2; 69 } 70 71 if (byte_count == 0) { 72 fprintf(stderr, "smbremountserver: byte count is 0\n"); 73 return 2; 74 } 75 76 blob = malloc(byte_count); 77 if (blob == NULL) { 78 fprintf(stderr, "smbremountserver: Can't allocate %u bytes\n", 79 byte_count); 80 return 2; 81 } 82 83 bytes_read = read(0, blob, byte_count); 84 if (bytes_read == -1) { 85 fprintf(stderr, "smbremountserver: Error reading blob: %s\n", 86 strerror(errno)); 87 return 2; 88 } 89 if (bytes_read < 0 || bytes_read != (ssize_t)byte_count) { 90 fprintf(stderr, "smbremountserver: Read only %zd bytes of %u-byte blob\n", 91 bytes_read, byte_count); 92 return 2; 93 } 94 95 /* 96 * OK, do this in a subsubprocess, so our parent can wait for us 97 * to exit and thus reap us, without blocking waiting for 98 * SMBRemountServer() to finish. 99 */ 100 switch ((child_pid = fork())) { 101 102 case -1: 103 /* 104 * Fork failure. Report an error and quit. 105 */ 106 fprintf(stderr, "smbremountserver: Cannot fork: %s\n", 107 strerror(errno)); 108 status = 2; 109 break; 110 111 case 0: 112 /* 113 * Child. Make the call, and quit. 114 */ 115 SMBRemountServer(blob, byte_count); 116 status = 0; 117 break; 118 119 default: 120 /* 121 * Parent. Just quit. 122 */ 123 status = 0; 124 break; 125 } 126 127 return status; 128} 129