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-rw-r--r--fs/ext4/crypto_fname.c268
-rw-r--r--fs/ext4/dir.c2
-rw-r--r--fs/ext4/ext4.h9
-rw-r--r--fs/ext4/namei.c72
-rw-r--r--fs/ext4/symlink.c2
5 files changed, 149 insertions, 204 deletions
diff --git a/fs/ext4/crypto_fname.c b/fs/ext4/crypto_fname.c
index ca2f5948c1ac..7a877e609e5f 100644
--- a/fs/ext4/crypto_fname.c
+++ b/fs/ext4/crypto_fname.c
@@ -198,106 +198,57 @@ static int ext4_fname_decrypt(struct ext4_fname_crypto_ctx *ctx,
return oname->len;
}
+static const char *lookup_table =
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,";
+
/**
* ext4_fname_encode_digest() -
*
* Encodes the input digest using characters from the set [a-zA-Z0-9_+].
* The encoded string is roughly 4/3 times the size of the input string.
*/
-int ext4_fname_encode_digest(char *dst, char *src, u32 len)
+static int digest_encode(const char *src, int len, char *dst)
{
- static const char *lookup_table =
- "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_+";
- u32 current_chunk, num_chunks, i;
- char tmp_buf[3];
- u32 c0, c1, c2, c3;
-
- current_chunk = 0;
- num_chunks = len/3;
- for (i = 0; i < num_chunks; i++) {
- c0 = src[3*i] & 0x3f;
- c1 = (((src[3*i]>>6)&0x3) | ((src[3*i+1] & 0xf)<<2)) & 0x3f;
- c2 = (((src[3*i+1]>>4)&0xf) | ((src[3*i+2] & 0x3)<<4)) & 0x3f;
- c3 = (src[3*i+2]>>2) & 0x3f;
- dst[4*i] = lookup_table[c0];
- dst[4*i+1] = lookup_table[c1];
- dst[4*i+2] = lookup_table[c2];
- dst[4*i+3] = lookup_table[c3];
- }
- if (i*3 < len) {
- memset(tmp_buf, 0, 3);
- memcpy(tmp_buf, &src[3*i], len-3*i);
- c0 = tmp_buf[0] & 0x3f;
- c1 = (((tmp_buf[0]>>6)&0x3) | ((tmp_buf[1] & 0xf)<<2)) & 0x3f;
- c2 = (((tmp_buf[1]>>4)&0xf) | ((tmp_buf[2] & 0x3)<<4)) & 0x3f;
- c3 = (tmp_buf[2]>>2) & 0x3f;
- dst[4*i] = lookup_table[c0];
- dst[4*i+1] = lookup_table[c1];
- dst[4*i+2] = lookup_table[c2];
- dst[4*i+3] = lookup_table[c3];
+ int i = 0, bits = 0, ac = 0;
+ char *cp = dst;
+
+ while (i < len) {
+ ac += (((unsigned char) src[i]) << bits);
+ bits += 8;
+ do {
+ *cp++ = lookup_table[ac & 0x3f];
+ ac >>= 6;
+ bits -= 6;
+ } while (bits >= 6);
i++;
}
- return (i * 4);
+ if (bits)
+ *cp++ = lookup_table[ac & 0x3f];
+ return cp - dst;
}
-/**
- * ext4_fname_hash() -
- *
- * This function computes the hash of the input filename, and sets the output
- * buffer to the *encoded* digest. It returns the length of the digest as its
- * return value. Errors are returned as negative numbers. We trust the caller
- * to allocate sufficient memory to oname string.
- */
-static int ext4_fname_hash(struct ext4_fname_crypto_ctx *ctx,
- const struct ext4_str *iname,
- struct ext4_str *oname)
+static int digest_decode(const char *src, int len, char *dst)
{
- struct scatterlist sg;
- struct hash_desc desc = {
- .tfm = (struct crypto_hash *)ctx->htfm,
- .flags = CRYPTO_TFM_REQ_MAY_SLEEP
- };
- int res = 0;
-
- if (iname->len <= EXT4_FNAME_CRYPTO_DIGEST_SIZE) {
- res = ext4_fname_encode_digest(oname->name, iname->name,
- iname->len);
- oname->len = res;
- return res;
- }
-
- sg_init_one(&sg, iname->name, iname->len);
- res = crypto_hash_init(&desc);
- if (res) {
- printk(KERN_ERR
- "%s: Error initializing crypto hash; res = [%d]\n",
- __func__, res);
- goto out;
- }
- res = crypto_hash_update(&desc, &sg, iname->len);
- if (res) {
- printk(KERN_ERR
- "%s: Error updating crypto hash; res = [%d]\n",
- __func__, res);
- goto out;
- }
- res = crypto_hash_final(&desc,
- &oname->name[EXT4_FNAME_CRYPTO_DIGEST_SIZE]);
- if (res) {
- printk(KERN_ERR
- "%s: Error finalizing crypto hash; res = [%d]\n",
- __func__, res);
- goto out;
+ int i = 0, bits = 0, ac = 0;
+ const char *p;
+ char *cp = dst;
+
+ while (i < len) {
+ p = strchr(lookup_table, src[i]);
+ if (p == NULL || src[i] == 0)
+ return -2;
+ ac += (p - lookup_table) << bits;
+ bits += 6;
+ if (bits >= 8) {
+ *cp++ = ac & 0xff;
+ ac >>= 8;
+ bits -= 8;
+ }
+ i++;
}
- /* Encode the digest as a printable string--this will increase the
- * size of the digest */
- oname->name[0] = 'I';
- res = ext4_fname_encode_digest(oname->name+1,
- &oname->name[EXT4_FNAME_CRYPTO_DIGEST_SIZE],
- EXT4_FNAME_CRYPTO_DIGEST_SIZE) + 1;
- oname->len = res;
-out:
- return res;
+ if (ac)
+ return -1;
+ return cp - dst;
}
/**
@@ -571,9 +522,13 @@ void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str)
* ext4_fname_disk_to_usr() - converts a filename from disk space to user space
*/
int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
- const struct ext4_str *iname,
- struct ext4_str *oname)
+ struct dx_hash_info *hinfo,
+ const struct ext4_str *iname,
+ struct ext4_str *oname)
{
+ char buf[24];
+ int ret;
+
if (ctx == NULL)
return -EIO;
if (iname->len < 3) {
@@ -587,18 +542,33 @@ int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
}
if (ctx->has_valid_key)
return ext4_fname_decrypt(ctx, iname, oname);
- else
- return ext4_fname_hash(ctx, iname, oname);
+
+ if (iname->len <= EXT4_FNAME_CRYPTO_DIGEST_SIZE) {
+ ret = digest_encode(iname->name, iname->len, oname->name);
+ oname->len = ret;
+ return ret;
+ }
+ if (hinfo) {
+ memcpy(buf, &hinfo->hash, 4);
+ memcpy(buf+4, &hinfo->minor_hash, 4);
+ } else
+ memset(buf, 0, 8);
+ memcpy(buf + 8, iname->name + iname->len - 16, 16);
+ oname->name[0] = '_';
+ ret = digest_encode(buf, 24, oname->name+1);
+ oname->len = ret + 1;
+ return ret + 1;
}
int ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+ struct dx_hash_info *hinfo,
const struct ext4_dir_entry_2 *de,
struct ext4_str *oname)
{
struct ext4_str iname = {.name = (unsigned char *) de->name,
.len = de->name_len };
- return _ext4_fname_disk_to_usr(ctx, &iname, oname);
+ return _ext4_fname_disk_to_usr(ctx, hinfo, &iname, oname);
}
@@ -640,10 +610,11 @@ int ext4_fname_usr_to_hash(struct ext4_fname_crypto_ctx *ctx,
const struct qstr *iname,
struct dx_hash_info *hinfo)
{
- struct ext4_str tmp, tmp2;
+ struct ext4_str tmp;
int ret = 0;
+ char buf[EXT4_FNAME_CRYPTO_DIGEST_SIZE+1];
- if (!ctx || !ctx->has_valid_key ||
+ if (!ctx ||
((iname->name[0] == '.') &&
((iname->len == 1) ||
((iname->name[1] == '.') && (iname->len == 2))))) {
@@ -651,59 +622,90 @@ int ext4_fname_usr_to_hash(struct ext4_fname_crypto_ctx *ctx,
return 0;
}
+ if (!ctx->has_valid_key && iname->name[0] == '_') {
+ if (iname->len != 33)
+ return -ENOENT;
+ ret = digest_decode(iname->name+1, iname->len, buf);
+ if (ret != 24)
+ return -ENOENT;
+ memcpy(&hinfo->hash, buf, 4);
+ memcpy(&hinfo->minor_hash, buf + 4, 4);
+ return 0;
+ }
+
+ if (!ctx->has_valid_key && iname->name[0] != '_') {
+ if (iname->len > 43)
+ return -ENOENT;
+ ret = digest_decode(iname->name, iname->len, buf);
+ ext4fs_dirhash(buf, ret, hinfo);
+ return 0;
+ }
+
/* First encrypt the plaintext name */
ret = ext4_fname_crypto_alloc_buffer(ctx, iname->len, &tmp);
if (ret < 0)
return ret;
ret = ext4_fname_encrypt(ctx, iname, &tmp);
- if (ret < 0)
- goto out;
-
- tmp2.len = (4 * ((EXT4_FNAME_CRYPTO_DIGEST_SIZE + 2) / 3)) + 1;
- tmp2.name = kmalloc(tmp2.len + 1, GFP_KERNEL);
- if (tmp2.name == NULL) {
- ret = -ENOMEM;
- goto out;
+ if (ret >= 0) {
+ ext4fs_dirhash(tmp.name, tmp.len, hinfo);
+ ret = 0;
}
- ret = ext4_fname_hash(ctx, &tmp, &tmp2);
- if (ret > 0)
- ext4fs_dirhash(tmp2.name, tmp2.len, hinfo);
- ext4_fname_crypto_free_buffer(&tmp2);
-out:
ext4_fname_crypto_free_buffer(&tmp);
return ret;
}
-/**
- * ext4_fname_disk_to_htree() - converts a filename from disk space to htree-access string
- */
-int ext4_fname_disk_to_hash(struct ext4_fname_crypto_ctx *ctx,
- const struct ext4_dir_entry_2 *de,
- struct dx_hash_info *hinfo)
+int ext4_fname_match(struct ext4_fname_crypto_ctx *ctx, struct ext4_str *cstr,
+ int len, const char * const name,
+ struct ext4_dir_entry_2 *de)
{
- struct ext4_str iname = {.name = (unsigned char *) de->name,
- .len = de->name_len};
- struct ext4_str tmp;
- int ret;
+ int ret = -ENOENT;
+ int bigname = (*name == '_');
- if (!ctx ||
- ((iname.name[0] == '.') &&
- ((iname.len == 1) ||
- ((iname.name[1] == '.') && (iname.len == 2))))) {
- ext4fs_dirhash(iname.name, iname.len, hinfo);
- return 0;
+ if (ctx->has_valid_key) {
+ if (cstr->name == NULL) {
+ struct qstr istr;
+
+ ret = ext4_fname_crypto_alloc_buffer(ctx, len, cstr);
+ if (ret < 0)
+ goto errout;
+ istr.name = name;
+ istr.len = len;
+ ret = ext4_fname_encrypt(ctx, &istr, cstr);
+ if (ret < 0)
+ goto errout;
+ }
+ } else {
+ if (cstr->name == NULL) {
+ cstr->name = kmalloc(32, GFP_KERNEL);
+ if (cstr->name == NULL)
+ return -ENOMEM;
+ if ((bigname && (len != 33)) ||
+ (!bigname && (len > 43)))
+ goto errout;
+ ret = digest_decode(name+bigname, len-bigname,
+ cstr->name);
+ if (ret < 0) {
+ ret = -ENOENT;
+ goto errout;
+ }
+ cstr->len = ret;
+ }
+ if (bigname) {
+ if (de->name_len < 16)
+ return 0;
+ ret = memcmp(de->name + de->name_len - 16,
+ cstr->name + 8, 16);
+ return (ret == 0) ? 1 : 0;
+ }
}
-
- tmp.len = (4 * ((EXT4_FNAME_CRYPTO_DIGEST_SIZE + 2) / 3)) + 1;
- tmp.name = kmalloc(tmp.len + 1, GFP_KERNEL);
- if (tmp.name == NULL)
- return -ENOMEM;
-
- ret = ext4_fname_hash(ctx, &iname, &tmp);
- if (ret > 0)
- ext4fs_dirhash(tmp.name, tmp.len, hinfo);
- ext4_fname_crypto_free_buffer(&tmp);
+ if (de->name_len != cstr->len)
+ return 0;
+ ret = memcmp(de->name, cstr->name, cstr->len);
+ return (ret == 0) ? 1 : 0;
+errout:
+ kfree(cstr->name);
+ cstr->name = NULL;
return ret;
}
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 61db51a5ce4c..5665d82d2332 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -249,7 +249,7 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
} else {
/* Directory is encrypted */
err = ext4_fname_disk_to_usr(enc_ctx,
- de, &fname_crypto_str);
+ NULL, de, &fname_crypto_str);
if (err < 0)
goto errout;
if (!dir_emit(ctx,
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 0179654faf79..dfb113816672 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2093,9 +2093,11 @@ u32 ext4_fname_crypto_round_up(u32 size, u32 blksize);
int ext4_fname_crypto_alloc_buffer(struct ext4_fname_crypto_ctx *ctx,
u32 ilen, struct ext4_str *crypto_str);
int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+ struct dx_hash_info *hinfo,
const struct ext4_str *iname,
struct ext4_str *oname);
int ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+ struct dx_hash_info *hinfo,
const struct ext4_dir_entry_2 *de,
struct ext4_str *oname);
int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx,
@@ -2104,11 +2106,12 @@ int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx,
int ext4_fname_usr_to_hash(struct ext4_fname_crypto_ctx *ctx,
const struct qstr *iname,
struct dx_hash_info *hinfo);
-int ext4_fname_disk_to_hash(struct ext4_fname_crypto_ctx *ctx,
- const struct ext4_dir_entry_2 *de,
- struct dx_hash_info *hinfo);
int ext4_fname_crypto_namelen_on_disk(struct ext4_fname_crypto_ctx *ctx,
u32 namelen);
+int ext4_fname_match(struct ext4_fname_crypto_ctx *ctx, struct ext4_str *cstr,
+ int len, const char * const name,
+ struct ext4_dir_entry_2 *de);
+
#ifdef CONFIG_EXT4_FS_ENCRYPTION
void ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx **ctx);
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 4f87127f781f..5ea737114716 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -640,7 +640,7 @@ static struct stats dx_show_leaf(struct inode *dir,
ext4_put_fname_crypto_ctx(&ctx);
ctx = NULL;
}
- res = ext4_fname_disk_to_usr(ctx, de,
+ res = ext4_fname_disk_to_usr(ctx, NULL, de,
&fname_crypto_str);
if (res < 0) {
printk(KERN_WARNING "Error "
@@ -653,15 +653,8 @@ static struct stats dx_show_leaf(struct inode *dir,
name = fname_crypto_str.name;
len = fname_crypto_str.len;
}
- res = ext4_fname_disk_to_hash(ctx, de,
- &h);
- if (res < 0) {
- printk(KERN_WARNING "Error "
- "converting filename "
- "from disk to htree"
- "\n");
- h.hash = 0xDEADBEEF;
- }
+ ext4fs_dirhash(de->name, de->name_len,
+ &h);
printk("%*.s:(E)%x.%u ", len, name,
h.hash, (unsigned) ((char *) de
- base));
@@ -1008,15 +1001,7 @@ static int htree_dirblock_to_tree(struct file *dir_file,
/* silently ignore the rest of the block */
break;
}
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
- err = ext4_fname_disk_to_hash(ctx, de, hinfo);
- if (err < 0) {
- count = err;
- goto errout;
- }
-#else
ext4fs_dirhash(de->name, de->name_len, hinfo);
-#endif
if ((hinfo->hash < start_hash) ||
((hinfo->hash == start_hash) &&
(hinfo->minor_hash < start_minor_hash)))
@@ -1032,7 +1017,7 @@ static int htree_dirblock_to_tree(struct file *dir_file,
&tmp_str);
} else {
/* Directory is encrypted */
- err = ext4_fname_disk_to_usr(ctx, de,
+ err = ext4_fname_disk_to_usr(ctx, hinfo, de,
&fname_crypto_str);
if (err < 0) {
count = err;
@@ -1193,26 +1178,10 @@ static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
int count = 0;
char *base = (char *) de;
struct dx_hash_info h = *hinfo;
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
- struct ext4_fname_crypto_ctx *ctx = NULL;
- int err;
-
- ctx = ext4_get_fname_crypto_ctx(dir, EXT4_NAME_LEN);
- if (IS_ERR(ctx))
- return PTR_ERR(ctx);
-#endif
while ((char *) de < base + blocksize) {
if (de->name_len && de->inode) {
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
- err = ext4_fname_disk_to_hash(ctx, de, &h);
- if (err < 0) {
- ext4_put_fname_crypto_ctx(&ctx);
- return err;
- }
-#else
ext4fs_dirhash(de->name, de->name_len, &h);
-#endif
map_tail--;
map_tail->hash = h.hash;
map_tail->offs = ((char *) de - base)>>2;
@@ -1223,9 +1192,6 @@ static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
/* XXX: do we need to check rec_len == 0 case? -Chris */
de = ext4_next_entry(de, blocksize);
}
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
- ext4_put_fname_crypto_ctx(&ctx);
-#endif
return count;
}
@@ -1287,16 +1253,8 @@ static inline int ext4_match(struct ext4_fname_crypto_ctx *ctx,
return 0;
#ifdef CONFIG_EXT4_FS_ENCRYPTION
- if (ctx) {
- /* Directory is encrypted */
- res = ext4_fname_disk_to_usr(ctx, de, fname_crypto_str);
- if (res < 0)
- return res;
- if (len != res)
- return 0;
- res = memcmp(name, fname_crypto_str->name, len);
- return (res == 0) ? 1 : 0;
- }
+ if (ctx)
+ return ext4_fname_match(ctx, fname_crypto_str, len, name, de);
#endif
if (len != de->name_len)
return 0;
@@ -1324,16 +1282,6 @@ int search_dir(struct buffer_head *bh, char *search_buf, int buf_size,
if (IS_ERR(ctx))
return -1;
- if (ctx != NULL) {
- /* Allocate buffer to hold maximum name length */
- res = ext4_fname_crypto_alloc_buffer(ctx, EXT4_NAME_LEN,
- &fname_crypto_str);
- if (res < 0) {
- ext4_put_fname_crypto_ctx(&ctx);
- return -1;
- }
- }
-
de = (struct ext4_dir_entry_2 *)search_buf;
dlimit = search_buf + buf_size;
while ((char *) de < dlimit) {
@@ -1872,14 +1820,6 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode,
return res;
}
reclen = EXT4_DIR_REC_LEN(res);
-
- /* Allocate buffer to hold maximum name length */
- res = ext4_fname_crypto_alloc_buffer(ctx, EXT4_NAME_LEN,
- &fname_crypto_str);
- if (res < 0) {
- ext4_put_fname_crypto_ctx(&ctx);
- return -1;
- }
}
de = (struct ext4_dir_entry_2 *)buf;
diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c
index 136ca0e911fd..ce2ed286ba08 100644
--- a/fs/ext4/symlink.c
+++ b/fs/ext4/symlink.c
@@ -74,7 +74,7 @@ static void *ext4_follow_link(struct dentry *dentry, struct nameidata *nd)
goto errout;
}
pstr.name = paddr;
- res = _ext4_fname_disk_to_usr(ctx, &cstr, &pstr);
+ res = _ext4_fname_disk_to_usr(ctx, NULL, &cstr, &pstr);
if (res < 0)
goto errout;
/* Null-terminate the name */
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