1 /*
2 * Copyright (c) 2023 Institute of Parallel And Distributed Systems (IPADS), Shanghai Jiao Tong University (SJTU)
3 * Licensed under the Mulan PSL v2.
4 * You can use this software according to the terms and conditions of the Mulan PSL v2.
5 * You may obtain a copy of Mulan PSL v2 at:
6 * http://license.coscl.org.cn/MulanPSL2
7 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR
8 * IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR FIT FOR A PARTICULAR
9 * PURPOSE.
10 * See the Mulan PSL v2 for more details.
11 */
12
13 #include <chcore/cpio.h>
14
15 #include <stdio.h>
16 #include <chcore/bug.h>
17 #include <chcore/defs.h>
18 #include <malloc.h>
19 #include <errno.h>
20 #include <chcore/error.h>
21 #include <string.h>
22
23 #define kwarn printf
24 #define cpio_info(fmt, ...) printf(fmt, ##__VA_ARGS__)
25 #define cpio_zalloc(sz) calloc(1, sz)
26 #define cpio_free(obj) free(obj)
27
28 struct {
29 struct cpio_file head;
30 struct cpio_file *tail;
31 } g_files;
32
hex8_u64(const char s[8])33 static u64 hex8_u64(const char s[8])
34 {
35 u64 u = 0;
36 for (int i = 0; i < 8; ++i) {
37 u <<= 4;
38 if (s[i] >= 'A' && s[i] <= 'F')
39 u += s[i] - 'A' + 10;
40 else
41 u += s[i] - '0';
42 }
43 return u;
44 }
45
cpio_parse_header(const void * addr,struct cpio_header * header)46 static int cpio_parse_header(const void *addr, struct cpio_header *header)
47 {
48 const struct cpio_newc_header *newc = addr;
49
50 // cpio_info("print in text: %s\n", addr);
51 /* headers other than newc are not supported */
52 BUG_ON(strncmp(newc->c_magic, "070701", 6));
53
54 header->c_ino = hex8_u64(newc->c_ino);
55 header->c_mode = hex8_u64(newc->c_mode);
56 header->c_uid = hex8_u64(newc->c_uid);
57 header->c_gid = hex8_u64(newc->c_gid);
58 header->c_nlink = hex8_u64(newc->c_nlink);
59 header->c_mtime = hex8_u64(newc->c_mtime);
60 header->c_filesize = hex8_u64(newc->c_filesize);
61 header->c_devmajor = hex8_u64(newc->c_devmajor);
62 header->c_devminor = hex8_u64(newc->c_devminor);
63 header->c_rdevmajor = hex8_u64(newc->c_rdevmajor);
64 header->c_rdevminor = hex8_u64(newc->c_rdevminor);
65 header->c_namesize = hex8_u64(newc->c_namesize);
66 header->c_check = hex8_u64(newc->c_check);
67
68 // cpio_info("header address is 0x%lx\n", (u64) header);
69 return 0;
70 }
71
cpio_extract_file(const void * addr,const char * dirat)72 int cpio_extract_file(const void *addr, const char *dirat)
73 {
74 return 0;
75 }
76
cpio_init_g_files(void)77 void cpio_init_g_files(void)
78 {
79 g_files.head.next = NULL;
80 g_files.tail = &g_files.head;
81 }
82
cpio_alloc_file(void)83 static struct cpio_file *cpio_alloc_file(void)
84 {
85 return cpio_zalloc(sizeof(struct cpio_file));
86 }
87
cpio_add_file(struct cpio_file * f)88 static void cpio_add_file(struct cpio_file *f)
89 {
90 f->next = NULL;
91 g_files.tail->next = f;
92 g_files.tail = f;
93 }
94
cpio_free_g_files(void)95 void cpio_free_g_files(void)
96 {
97 struct cpio_file *f, *next;
98
99 f = g_files.head.next;
100 if (f) {
101 next = f->next;
102 } else {
103 return;
104 }
105
106 for (;;) {
107 free(f);
108 f = next;
109 if (next) {
110 next = next->next;
111 }
112
113 if (!f) {
114 break;
115 }
116 }
117
118 // to keep the list head represented by g_files
119 // consistent
120 cpio_init_g_files();
121 }
122
cpio_extract(const void * addr,const char * dirat)123 void cpio_extract(const void *addr, const char *dirat)
124 {
125 const char *p = addr;
126 struct cpio_file *f;
127 int err;
128
129 for (;;) {
130 f = cpio_alloc_file();
131 // printf("cpio_alloc_file returns %p\n", f);
132 if (f == NULL) {
133 kwarn("cpio_alloc_file fails due to lack of memory.\n");
134 return;
135 }
136
137 BUG_ON(!f);
138
139 err = cpio_parse_header(p, &f->header);
140 BUG_ON(err);
141 p += sizeof(struct cpio_newc_header);
142
143 if (0 == strcmp(p, "TRAILER!!!")) {
144 cpio_free(f);
145 break;
146 }
147
148 f->name = p;
149 p += f->header.c_namesize;
150 p = (void *)ALIGN4_UP(p);
151
152 f->data = p;
153 p += f->header.c_filesize;
154 p = (void *)ALIGN4_UP(p);
155
156 cpio_add_file(f);
157 }
158 }
159
cpio_extract_single(const void * addr,const char * target,int (* cpio_single_file_filler)(const void * start,size_t size,void * data),void * data)160 int cpio_extract_single(const void *addr, const char *target,
161 int (*cpio_single_file_filler)(const void *start,
162 size_t size, void *data),
163 void *data)
164 {
165 const char *p = addr;
166 struct cpio_header header;
167 const char *filename;
168
169 /* Skip leading '/' */
170 target = target + 1;
171
172 for (;;) {
173 int err;
174
175 err = cpio_parse_header(p, &header);
176 BUG_ON(err);
177 p += sizeof(struct cpio_newc_header);
178
179 if (0 == strcmp(p, "TRAILER!!!"))
180 break;
181
182 filename = p;
183 p += header.c_namesize;
184 p = (void *)ALIGN4_UP(p);
185
186 if (0 == strcmp(filename, target)) {
187 return cpio_single_file_filler(p, header.c_filesize, data);
188 }
189
190 p += header.c_filesize;
191 p = (void *)ALIGN4_UP(p);
192 }
193 return -ENOENT;
194 }
195