1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include <errno.h> 18#include <inttypes.h> 19#include <limits.h> 20#include <stdio.h> 21#include <stdlib.h> 22#include <string.h> 23 24#include <private/android_filesystem_config.h> 25#include <private/canned_fs_config.h> 26 27typedef struct { 28 const char* path; 29 unsigned uid; 30 unsigned gid; 31 unsigned mode; 32 uint64_t capabilities; 33} Path; 34 35static Path* canned_data = NULL; 36static int canned_alloc = 0; 37static int canned_used = 0; 38 39static int path_compare(const void* a, const void* b) { 40 return strcmp(((Path*)a)->path, ((Path*)b)->path); 41} 42 43int load_canned_fs_config(const char* fn) { 44 char line[PATH_MAX + 200]; 45 FILE* f; 46 47 f = fopen(fn, "r"); 48 if (f == NULL) { 49 fprintf(stderr, "failed to open %s: %s\n", fn, strerror(errno)); 50 return -1; 51 } 52 53 while (fgets(line, sizeof(line), f)) { 54 Path* p; 55 char* token; 56 57 while (canned_used >= canned_alloc) { 58 canned_alloc = (canned_alloc+1) * 2; 59 canned_data = (Path*) realloc(canned_data, canned_alloc * sizeof(Path)); 60 } 61 p = canned_data + canned_used; 62 p->path = strdup(strtok(line, " ")); 63 p->uid = atoi(strtok(NULL, " ")); 64 p->gid = atoi(strtok(NULL, " ")); 65 p->mode = strtol(strtok(NULL, " "), NULL, 8); // mode is in octal 66 p->capabilities = 0; 67 68 do { 69 token = strtok(NULL, " "); 70 if (token && strncmp(token, "capabilities=", 13) == 0) { 71 p->capabilities = strtoll(token+13, NULL, 0); 72 break; 73 } 74 } while (token); 75 76 canned_used++; 77 } 78 79 fclose(f); 80 81 qsort(canned_data, canned_used, sizeof(Path), path_compare); 82 printf("loaded %d fs_config entries\n", canned_used); 83 84 return 0; 85} 86 87static const int kDebugCannedFsConfig = 0; 88 89void canned_fs_config(const char* path, int dir, const char* target_out_path, 90 unsigned* uid, unsigned* gid, unsigned* mode, uint64_t* capabilities) { 91 Path key, *p; 92 93 key.path = path; 94 if (path[0] == '/') key.path++; // canned paths lack the leading '/' 95 p = (Path*) bsearch(&key, canned_data, canned_used, sizeof(Path), path_compare); 96 if (p == NULL) { 97 fprintf(stderr, "failed to find [%s] in canned fs_config\n", path); 98 exit(1); 99 } 100 *uid = p->uid; 101 *gid = p->gid; 102 *mode = p->mode; 103 *capabilities = p->capabilities; 104 105 if (kDebugCannedFsConfig) { 106 // for debugging, run the built-in fs_config and compare the results. 107 108 unsigned c_uid, c_gid, c_mode; 109 uint64_t c_capabilities; 110 111 fs_config(path, dir, target_out_path, &c_uid, &c_gid, &c_mode, &c_capabilities); 112 113 if (c_uid != *uid) printf("%s uid %d %d\n", path, *uid, c_uid); 114 if (c_gid != *gid) printf("%s gid %d %d\n", path, *gid, c_gid); 115 if (c_mode != *mode) printf("%s mode 0%o 0%o\n", path, *mode, c_mode); 116 if (c_capabilities != *capabilities) { 117 printf("%s capabilities %" PRIx64 " %" PRIx64 "\n", 118 path, 119 *capabilities, 120 c_capabilities); 121 } 122 } 123} 124