1 /*
2 * Copyright (C) 2008 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 <fs_mgr.h>
18 #include "bootloader.h"
19 #include "common.h"
20 #include "mtdutils/mtdutils.h"
21 #include "roots.h"
22
23 #include <errno.h>
24 #include <stdio.h>
25 #include <string.h>
26 #include <sys/stat.h>
27 #include <unistd.h>
28
29 static int get_bootloader_message_mtd(struct bootloader_message *out, const Volume* v);
30 static int set_bootloader_message_mtd(const struct bootloader_message *in, const Volume* v);
31 static int get_bootloader_message_block(struct bootloader_message *out, const Volume* v);
32 static int set_bootloader_message_block(const struct bootloader_message *in, const Volume* v);
33
get_bootloader_message(struct bootloader_message * out)34 int get_bootloader_message(struct bootloader_message *out) {
35 Volume* v = volume_for_path("/misc");
36 if (v == NULL) {
37 LOGE("Cannot load volume /misc!\n");
38 return -1;
39 }
40 if (strcmp(v->fs_type, "mtd") == 0) {
41 return get_bootloader_message_mtd(out, v);
42 } else if (strcmp(v->fs_type, "emmc") == 0) {
43 return get_bootloader_message_block(out, v);
44 }
45 LOGE("unknown misc partition fs_type \"%s\"\n", v->fs_type);
46 return -1;
47 }
48
set_bootloader_message(const struct bootloader_message * in)49 int set_bootloader_message(const struct bootloader_message *in) {
50 Volume* v = volume_for_path("/misc");
51 if (v == NULL) {
52 LOGE("Cannot load volume /misc!\n");
53 return -1;
54 }
55 if (strcmp(v->fs_type, "mtd") == 0) {
56 return set_bootloader_message_mtd(in, v);
57 } else if (strcmp(v->fs_type, "emmc") == 0) {
58 return set_bootloader_message_block(in, v);
59 }
60 LOGE("unknown misc partition fs_type \"%s\"\n", v->fs_type);
61 return -1;
62 }
63
64 // ------------------------------
65 // for misc partitions on MTD
66 // ------------------------------
67
68 static const int MISC_PAGES = 3; // number of pages to save
69 static const int MISC_COMMAND_PAGE = 1; // bootloader command is this page
70
get_bootloader_message_mtd(struct bootloader_message * out,const Volume * v)71 static int get_bootloader_message_mtd(struct bootloader_message *out,
72 const Volume* v) {
73 size_t write_size;
74 mtd_scan_partitions();
75 const MtdPartition *part = mtd_find_partition_by_name(v->blk_device);
76 if (part == NULL || mtd_partition_info(part, NULL, NULL, &write_size)) {
77 LOGE("Can't find %s\n", v->blk_device);
78 return -1;
79 }
80
81 MtdReadContext *read = mtd_read_partition(part);
82 if (read == NULL) {
83 LOGE("Can't open %s\n(%s)\n", v->blk_device, strerror(errno));
84 return -1;
85 }
86
87 const ssize_t size = write_size * MISC_PAGES;
88 char data[size];
89 ssize_t r = mtd_read_data(read, data, size);
90 if (r != size) LOGE("Can't read %s\n(%s)\n", v->blk_device, strerror(errno));
91 mtd_read_close(read);
92 if (r != size) return -1;
93
94 memcpy(out, &data[write_size * MISC_COMMAND_PAGE], sizeof(*out));
95 return 0;
96 }
set_bootloader_message_mtd(const struct bootloader_message * in,const Volume * v)97 static int set_bootloader_message_mtd(const struct bootloader_message *in,
98 const Volume* v) {
99 size_t write_size;
100 mtd_scan_partitions();
101 const MtdPartition *part = mtd_find_partition_by_name(v->blk_device);
102 if (part == NULL || mtd_partition_info(part, NULL, NULL, &write_size)) {
103 LOGE("Can't find %s\n", v->blk_device);
104 return -1;
105 }
106
107 MtdReadContext *read = mtd_read_partition(part);
108 if (read == NULL) {
109 LOGE("Can't open %s\n(%s)\n", v->blk_device, strerror(errno));
110 return -1;
111 }
112
113 ssize_t size = write_size * MISC_PAGES;
114 char data[size];
115 ssize_t r = mtd_read_data(read, data, size);
116 if (r != size) LOGE("Can't read %s\n(%s)\n", v->blk_device, strerror(errno));
117 mtd_read_close(read);
118 if (r != size) return -1;
119
120 memcpy(&data[write_size * MISC_COMMAND_PAGE], in, sizeof(*in));
121
122 MtdWriteContext *write = mtd_write_partition(part);
123 if (write == NULL) {
124 LOGE("Can't open %s\n(%s)\n", v->blk_device, strerror(errno));
125 return -1;
126 }
127 if (mtd_write_data(write, data, size) != size) {
128 LOGE("Can't write %s\n(%s)\n", v->blk_device, strerror(errno));
129 mtd_write_close(write);
130 return -1;
131 }
132 if (mtd_write_close(write)) {
133 LOGE("Can't finish %s\n(%s)\n", v->blk_device, strerror(errno));
134 return -1;
135 }
136
137 LOGI("Set boot command \"%s\"\n", in->command[0] != 255 ? in->command : "");
138 return 0;
139 }
140
141
142 // ------------------------------------
143 // for misc partitions on block devices
144 // ------------------------------------
145
wait_for_device(const char * fn)146 static void wait_for_device(const char* fn) {
147 int tries = 0;
148 int ret;
149 struct stat buf;
150 do {
151 ++tries;
152 ret = stat(fn, &buf);
153 if (ret) {
154 printf("stat %s try %d: %s\n", fn, tries, strerror(errno));
155 sleep(1);
156 }
157 } while (ret && tries < 10);
158 if (ret) {
159 printf("failed to stat %s\n", fn);
160 }
161 }
162
get_bootloader_message_block(struct bootloader_message * out,const Volume * v)163 static int get_bootloader_message_block(struct bootloader_message *out,
164 const Volume* v) {
165 wait_for_device(v->blk_device);
166 FILE* f = fopen(v->blk_device, "rb");
167 if (f == NULL) {
168 LOGE("Can't open %s\n(%s)\n", v->blk_device, strerror(errno));
169 return -1;
170 }
171 struct bootloader_message temp;
172 int count = fread(&temp, sizeof(temp), 1, f);
173 if (count != 1) {
174 LOGE("Failed reading %s\n(%s)\n", v->blk_device, strerror(errno));
175 return -1;
176 }
177 if (fclose(f) != 0) {
178 LOGE("Failed closing %s\n(%s)\n", v->blk_device, strerror(errno));
179 return -1;
180 }
181 memcpy(out, &temp, sizeof(temp));
182 return 0;
183 }
184
set_bootloader_message_block(const struct bootloader_message * in,const Volume * v)185 static int set_bootloader_message_block(const struct bootloader_message *in,
186 const Volume* v) {
187 wait_for_device(v->blk_device);
188 FILE* f = fopen(v->blk_device, "wb");
189 if (f == NULL) {
190 LOGE("Can't open %s\n(%s)\n", v->blk_device, strerror(errno));
191 return -1;
192 }
193 int count = fwrite(in, sizeof(*in), 1, f);
194 if (count != 1) {
195 LOGE("Failed writing %s\n(%s)\n", v->blk_device, strerror(errno));
196 return -1;
197 }
198 if (fclose(f) != 0) {
199 LOGE("Failed closing %s\n(%s)\n", v->blk_device, strerror(errno));
200 return -1;
201 }
202 return 0;
203 }
204