fs/squashfs/Kconfig
2 2 tristate "SquashFS 4.0 - Squashed file system support" 3 3 depends on BLOCK 4 4 select CRYPTO 5 select CRYPTO_ZLIB 6 5 help 7 6 Saying Y here includes support for SquashFS 4.0 (a Compressed 8 7 Read-Only File System). Squashfs is a highly compressed read-only 鈥?/a> 鈥?/a> 37 36 38 37 If unsure, say N. 39 38 39 config SQUASHFS_SUPPORT_ZLIB 40 bool 41 prompt "Support ZLIB compression" if SQUASHFS_SUPPORT_LZMA 42 depends on SQUASHFS 43 select CRYPTO_ZLIB 44 default y 45 help 46 ZLIB is the default compression used in squashfs. If you are 47 using LZMA compression instead, you can remove support for ZLIB 48 entirely. 49 50 config SQUASHFS_SUPPORT_LZMA 51 bool "Support LZMA compression" 52 depends on SQUASHFS 53 select CRYPTO_LZMA 54 help 55 By default SquashFS uses ZLIB compression, however (if your tools 56 support it, you can use LZMA instead, which saves space. 57 58 40 59 config SQUASHFS_FRAGMENT_CACHE_SIZE 41 60 int "Number of fragments cached" if SQUASHFS_EMBEDDED 42 61 depends on SQUASHFSTabularUnified fs/squashfs/squashfs_fs.h
212 212 * definitions for structures on disk
213 213 */
214 214 #define ZLIB_COMPRESSION 1
215 #define LZMA_COMPRESSION 2
215 216
216 217 struct squashfs_super_block {
217 218 __le32 s_magic;
TabularUnified fs/squashfs/super.c
47 47 #include "squashfs.h"
48 48
49 49
50 #define SQUASHFS_CRYPTO_ALG "zlib"
50 static int squashfs_setup_zlib(struct squashfs_sb_info *msblk)
51 {
52 int err = -EOPNOTSUPP;
53
54 #ifdef CONFIG_SQUASHFS_SUPPORT_ZLIB
55 struct {
56 struct nlattr nla;
57 int val;
58 } params = {
59 .nla = {
60 .nla_len = nla_attr_size(sizeof(int)),
61 .nla_type = ZLIB_DECOMP_WINDOWBITS,
62 },
63 .val = DEF_WBITS,
64 };
65
66 msblk->tfm = crypto_alloc_pcomp("zlib", 0,
67 CRYPTO_ALG_ASYNC);
68 if (IS_ERR(msblk->tfm)) {
69 ERROR("Failed to load zlib crypto module\n");
70 return PTR_ERR(msblk->tfm);
71 }
72
73 err = crypto_decompress_setup(msblk->tfm, ¶ms, sizeof(params));
74 if (err) {
75 ERROR("Failed to set up decompression parameters\n");
76 crypto_free_pcomp(msblk->tfm);
77 }
78 #endif
51 79
80 return err;
81 }
82
83 static int squashfs_setup_lzma(struct squashfs_sb_info *msblk)
84 {
85 int err = -EOPNOTSUPP;
86
87 #ifdef CONFIG_SQUASHFS_SUPPORT_LZMA
88 msblk->tfm = crypto_alloc_pcomp("lzma", 0,
89 CRYPTO_ALG_ASYNC);
90 if (IS_ERR(msblk->tfm)) {
91 ERROR("Failed to load lzma crypto module\n");
92 return PTR_ERR(msblk->tfm);
93 }
94
95 err = crypto_decompress_setup(msblk->tfm, NULL, 0);
96 if (err) {
97 ERROR("Failed to set up decompression parameters\n");
98 crypto_free_pcomp(msblk->tfm);
99 }
100 #endif
101
102 return err;
103 }
52 104
53 105 static struct file_system_type squashfs_fs_type;
54 106 static struct super_operations squashfs_super_ops;
55 107
56 static int supported_squashfs_filesystem(short major, short minor, short comp)
108 static int supported_squashfs_filesystem(short major, short minor)
57 109 {
58 110 if (major < SQUASHFS_MAJOR) {
59 111 ERROR("Major/Minor mismatch, older Squashfs %d.%d "
鈥?/a> 鈥?/a>
66 118 return -EINVAL;
67 119 }
68 120
69 if (comp != ZLIB_COMPRESSION)
70 return -EINVAL;
71
72 121 return 0;
73 122 }
74 123
鈥?/a> 鈥?/a>
83 132 unsigned short flags;
84 133 unsigned int fragments;
85 134 u64 lookup_table_start;
86 struct {
87 struct nlattr nla;
88 int val;
89 } params = {
90 .nla = {
91 .nla_len = nla_attr_size(sizeof(int)),
92 .nla_type = ZLIB_DECOMP_WINDOWBITS,
93 },
94 .val = DEF_WBITS,
95 };
96 135 int err;
97 136
98 137 TRACE("Entered squashfs_fill_superblock\n");
鈥?/a> 鈥?/a>
104 143 }
105 144 msblk = sb->s_fs_info;
106 145
107 msblk->tfm = crypto_alloc_pcomp(SQUASHFS_CRYPTO_ALG, 0,
108 CRYPTO_ALG_ASYNC);
109 if (IS_ERR(msblk->tfm)) {
110 ERROR("Failed to load %s crypto module\n",
111 SQUASHFS_CRYPTO_ALG);
112 err = PTR_ERR(msblk->tfm);
113 goto failed_pcomp;
114 }
115
116 err = crypto_decompress_setup(msblk->tfm, ¶ms, sizeof(params));
117 if (err) {
118 ERROR("Failed to set up decompression parameters\n");
119 goto failure;
120 }
121
122 146 sblk = kzalloc(sizeof(*sblk), GFP_KERNEL);
123 147 if (sblk == NULL) {
124 148 ERROR("Failed to allocate squashfs_super_block\n");
鈥?/a> 鈥?/a>
158 182
159 183 /* Check the MAJOR & MINOR versions and compression type */
160 184 err = supported_squashfs_filesystem(le16_to_cpu(sblk->s_major),
161 le16_to_cpu(sblk->s_minor),
162 le16_to_cpu(sblk->compression));
185 le16_to_cpu(sblk->s_minor));
186 if (err < 0)
187 goto failed_mount;
188
189 switch(le16_to_cpu(sblk->compression)) {
190 case ZLIB_COMPRESSION:
191 err = squashfs_setup_zlib(msblk);
192 break;
193 case LZMA_COMPRESSION:
194 err = squashfs_setup_lzma(msblk);
195 break;
196 default:
197 err = -EINVAL;
198 break;
199 }
163 200 if (err < 0)
164 201 goto failed_mount;
165 202
鈥?/a> 鈥?/a>
305 342 return 0;
306 343
307 344 failed_mount:
345 if (msblk->tfm)
346 crypto_free_pcomp(msblk->tfm);
308 347 squashfs_cache_delete(msblk->block_cache);
309 348 squashfs_cache_delete(msblk->fragment_cache);
310 349 squashfs_cache_delete(msblk->read_page);
311 350 kfree(msblk->inode_lookup_table);
312 351 kfree(msblk->fragment_index);
313 352 kfree(msblk->id_table);
314 crypto_free_pcomp(msblk->tfm);
315 kfree(sb->s_fs_info);
316 sb->s_fs_info = NULL;
317 353 kfree(sblk);
318 return err;
319
320 354 failure:
321 crypto_free_pcomp(msblk->tfm);
322 failed_pcomp:
323 355 kfree(sb->s_fs_info);
324 356 sb->s_fs_info = NULL;
325 357 return err;
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