1 /*
2 * Copyright (C) 2016 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 #define DEBUG false
17 #include "Log.h"
18
19 #include "report_directory.h"
20
21 #include <private/android_filesystem_config.h>
22 #include <utils/String8.h>
23
24 #include <dirent.h>
25 #include <libgen.h>
26 #include <sys/stat.h>
27 #include <sys/types.h>
28 #include <unistd.h>
29
30 #include <vector>
31
32 namespace android {
33 namespace os {
34 namespace incidentd {
35
create_directory(const char * directory)36 status_t create_directory(const char* directory) {
37 struct stat st;
38 status_t err = NO_ERROR;
39 char* dir = strdup(directory);
40
41 // Skip first slash
42 char* d = dir + 1;
43
44 // Create directories, assigning them to the system user
45 bool last = false;
46 while (!last) {
47 d = strchr(d, '/');
48 if (d != NULL) {
49 *d = '\0';
50 } else {
51 last = true;
52 }
53 if (stat(dir, &st) == 0) {
54 if (!S_ISDIR(st.st_mode)) {
55 err = ALREADY_EXISTS;
56 goto done;
57 }
58 } else {
59 ALOGE("No such directory %s, something wrong.", dir);
60 err = -1;
61 goto done;
62 }
63 if (!last) {
64 *d++ = '/';
65 }
66 }
67
68 // Ensure that the final directory is owned by the system with 0770. If it isn't
69 // we won't write into it.
70 if (stat(directory, &st) != 0) {
71 ALOGE("No incident reports today. Can't stat: %s", directory);
72 err = -errno;
73 goto done;
74 }
75 if ((st.st_mode & 0777) != 0770) {
76 ALOGE("No incident reports today. Mode is %0o on report directory %s", st.st_mode,
77 directory);
78 err = BAD_VALUE;
79 goto done;
80 }
81 if (st.st_uid != AID_INCIDENTD || st.st_gid != AID_INCIDENTD) {
82 ALOGE("No incident reports today. Owner is %d and group is %d on report directory %s",
83 st.st_uid, st.st_gid, directory);
84 err = BAD_VALUE;
85 goto done;
86 }
87
88 done:
89 free(dir);
90 return err;
91 }
92
stat_mtime_cmp(const std::pair<String8,struct stat> & a,const std::pair<String8,struct stat> & b)93 static bool stat_mtime_cmp(const std::pair<String8, struct stat>& a,
94 const std::pair<String8, struct stat>& b) {
95 return a.second.st_mtime < b.second.st_mtime;
96 }
97
clean_directory(const char * directory,off_t maxSize,size_t maxCount)98 void clean_directory(const char* directory, off_t maxSize, size_t maxCount) {
99 DIR* dir;
100 struct dirent* entry;
101 struct stat st;
102
103 std::vector<std::pair<String8, struct stat>> files;
104
105 if ((dir = opendir(directory)) == NULL) {
106 ALOGE("Couldn't open incident directory: %s", directory);
107 return;
108 }
109
110 String8 dirbase(directory);
111 if (directory[dirbase.size() - 1] != '/') dirbase += "/";
112
113 off_t totalSize = 0;
114 size_t totalCount = 0;
115
116 // Enumerate, count and add up size
117 while ((entry = readdir(dir)) != NULL) {
118 if (entry->d_name[0] == '.') {
119 continue;
120 }
121 String8 filename = dirbase + entry->d_name;
122 if (stat(filename.string(), &st) != 0) {
123 ALOGE("Unable to stat file %s", filename.string());
124 continue;
125 }
126 if (!S_ISREG(st.st_mode)) {
127 continue;
128 }
129 files.push_back(std::pair<String8, struct stat>(filename, st));
130
131 totalSize += st.st_size;
132 totalCount++;
133 }
134
135 closedir(dir);
136
137 // Count or size is less than max, then we're done.
138 if (totalSize < maxSize && totalCount < maxCount) {
139 return;
140 }
141
142 // Oldest files first.
143 sort(files.begin(), files.end(), stat_mtime_cmp);
144
145 // Remove files until we're under our limits.
146 for (std::vector<std::pair<String8, struct stat>>::iterator it = files.begin();
147 it != files.end() && totalSize >= maxSize && totalCount >= maxCount; it++) {
148 remove(it->first.string());
149 totalSize -= it->second.st_size;
150 totalCount--;
151 }
152 }
153
154 } // namespace incidentd
155 } // namespace os
156 } // namespace android