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/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <private/android_filesystem_config.h>
#include <private/canned_fs_config.h>
#include <private/fs_config.h>
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct {
const char* path;
unsigned uid;
unsigned gid;
unsigned mode;
uint64_t capabilities;
} Path;
static Path* canned_data = NULL;
static int canned_alloc = 0;
static int canned_used = 0;
static int path_compare(const void* a, const void* b) {
return strcmp(((Path*)a)->path, ((Path*)b)->path);
}
int load_canned_fs_config(const char* fn) {
char buf[PATH_MAX + 200];
FILE* f;
f = fopen(fn, "r");
if (f == NULL) {
fprintf(stderr, "failed to open %s: %s\n", fn, strerror(errno));
return -1;
}
while (fgets(buf, sizeof(buf), f)) {
Path* p;
char* token;
char* line = buf;
bool rootdir;
while (canned_used >= canned_alloc) {
canned_alloc = (canned_alloc+1) * 2;
canned_data = (Path*) realloc(canned_data, canned_alloc * sizeof(Path));
}
p = canned_data + canned_used;
if (line[0] == '/') line++;
rootdir = line[0] == ' ';
p->path = strdup(rootdir ? "" : strtok(line, " "));
p->uid = atoi(strtok(rootdir ? line : NULL, " "));
p->gid = atoi(strtok(NULL, " "));
p->mode = strtol(strtok(NULL, " "), NULL, 8); // mode is in octal
p->capabilities = 0;
do {
token = strtok(NULL, " ");
if (token && strncmp(token, "capabilities=", 13) == 0) {
p->capabilities = strtoll(token+13, NULL, 0);
break;
}
} while (token);
canned_used++;
}
fclose(f);
qsort(canned_data, canned_used, sizeof(Path), path_compare);
printf("loaded %d fs_config entries\n", canned_used);
return 0;
}
static const int kDebugCannedFsConfig = 0;
void canned_fs_config(const char* path, int dir, const char* target_out_path,
unsigned* uid, unsigned* gid, unsigned* mode, uint64_t* capabilities) {
Path key, *p;
key.path = path;
if (path[0] == '/') key.path++; // canned paths lack the leading '/'
p = (Path*) bsearch(&key, canned_data, canned_used, sizeof(Path), path_compare);
if (p == NULL) {
fprintf(stderr, "failed to find [%s] in canned fs_config\n", path);
exit(1);
}
*uid = p->uid;
*gid = p->gid;
*mode = p->mode;
*capabilities = p->capabilities;
if (kDebugCannedFsConfig) {
// for debugging, run the built-in fs_config and compare the results.
unsigned c_uid, c_gid, c_mode;
uint64_t c_capabilities;
fs_config(path, dir, target_out_path, &c_uid, &c_gid, &c_mode, &c_capabilities);
if (c_uid != *uid) printf("%s uid %d %d\n", path, *uid, c_uid);
if (c_gid != *gid) printf("%s gid %d %d\n", path, *gid, c_gid);
if (c_mode != *mode) printf("%s mode 0%o 0%o\n", path, *mode, c_mode);
if (c_capabilities != *capabilities) {
printf("%s capabilities %" PRIx64 " %" PRIx64 "\n",
path,
*capabilities,
c_capabilities);
}
}
}
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