代码拉取完成，页面将自动刷新
From 31fa7a20018207ed15751e1c19efe58ad46ed32c Mon Sep 17 00:00:00 2001
From: ChenXiaoSong <chenxiaosongemail@foxmail.com>
Date: Wed, 31 Jan 2024 09:13:32 +0000
Subject: [PATCH] minix: support long file name
Signed-off-by: ChenXiaoSong <chenxiaosongemail@foxmail.com>
---
fs/minix/dir.c | 12 +++
fs/minix/namei.c | 12 ++-
fs/namei.c | 183 +++++++++++++++++++++++++++++++++++++++++++++
include/linux/fs.h | 8 ++
4 files changed, 213 insertions(+), 2 deletions(-)
diff --git a/fs/minix/dir.c b/fs/minix/dir.c
index a224cf222570..2c9e1a60462a 100644
--- a/fs/minix/dir.c
+++ b/fs/minix/dir.c
@@ -120,6 +120,18 @@ static int minix_readdir(struct file *file, struct dir_context *ctx)
}
if (inumber) {
unsigned l = strnlen(name, sbi->s_namelen);
+ if (strcmp(name, ".") && strcmp(name, "..") &&
+ !strncmp(name, CXS_HASH_PREFIX, strlen(CXS_HASH_PREFIX))) {
+ char full_name[CXS_FILENAME_MAXLEN + 1];
+ cxs_unhash_filename2(name, full_name, sizeof(full_name));
+ char *filename;
+ l = strlen(full_name);
+ /* TODO: free it */
+ filename = kzalloc(l+1, GFP_KERNEL);
+ memcpy(filename, full_name, l);
+ name = filename;
+ }
+
if (!dir_emit(ctx, name, l,
inumber, DT_UNKNOWN)) {
unmap_and_put_page(page, p);
diff --git a/fs/minix/namei.c b/fs/minix/namei.c
index d6031acc34f0..a8b60049763d 100644
--- a/fs/minix/namei.c
+++ b/fs/minix/namei.c
@@ -24,8 +24,16 @@ static struct dentry *minix_lookup(struct inode * dir, struct dentry *dentry, un
struct inode * inode = NULL;
ino_t ino;
- if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen)
- return ERR_PTR(-ENAMETOOLONG);
+ if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen) {
+ /* TODO: free filename */
+ char *filename = kzalloc(minix_sb(dir->i_sb)->s_namelen+1,
+ GFP_KERNEL);
+ char hash_name[CXS_HASH_NAME_LEN];
+ cxs_hash_filename2(dentry->d_name.name, hash_name, sizeof(hash_name));
+ memcpy(filename, hash_name, strlen(hash_name)+1);
+ dentry->d_name.name = filename;
+ dentry->d_name.len = strlen(filename);
+ }
ino = minix_inode_by_name(dentry);
if (ino)
diff --git a/fs/namei.c b/fs/namei.c
index 9342fa6a38c2..cc73f54b2a9a 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -131,7 +131,30 @@ getname_flags(const char __user *filename, int flags, int *empty)
{
struct filename *result;
char *kname;
+ char hash_name[CXS_HASH_NAME_LEN];
int len;
+ int len_user;
+ char *kfilename;
+ char *last_slash;
+ char *last_path;
+ int prefix_path_len;
+
+ len_user = strnlen_user(filename, CXS_FILENAME_MAXLEN+1); // INCLUDING final NULL
+ kfilename = kzalloc(len_user+1, GFP_KERNEL);
+ copy_from_user(kfilename, filename, len_user);
+ last_slash = strrchr(kfilename, '/');
+ if (last_slash) {
+ last_path = last_slash + 1;
+ prefix_path_len = last_slash - kfilename + 1;
+ } else {
+ last_path = kfilename;
+ prefix_path_len = 0;
+ }
+ if (len_user > CXS_SHORT_FILENAME_MAXLEN + 1) {
+ cxs_hash_filename2(last_path, hash_name, sizeof(hash_name));
+ copy_to_user(filename + prefix_path_len, hash_name,
+ strlen(hash_name)+1);
+ }
result = audit_reusename(filename);
if (result)
@@ -205,6 +228,166 @@ getname_flags(const char __user *filename, int flags, int *empty)
return result;
}
+static LIST_HEAD(cxs_long_filename_list);
+
+struct cxs_long_filename {
+ struct list_head list;
+ char *name;
+ char *hash_name;
+};
+
+static int simple_hash(const char *name)
+{
+ int i;
+ int res = 0;
+ for (i = 0; i < strlen(name); i++) {
+ res += name[i];
+ }
+ return res;
+}
+
+char *cxs_hash_filename(const char *name)
+{
+ unsigned int hash;
+ struct cxs_long_filename *lf;
+ struct cxs_long_filename *tmp_lf;
+ unsigned int hash_name_len = strlen(CXS_HASH_PREFIX)+65;
+
+ lf = kmalloc(sizeof(struct cxs_long_filename), GFP_KERNEL);
+ lf->name = kzalloc(strlen(name)+1, GFP_KERNEL);
+ lf->hash_name = kzalloc(hash_name_len, GFP_KERNEL);
+ strcpy(lf->name, name);
+ hash = simple_hash(name); // or use full_name_hash ?
+ snprintf(lf->hash_name, hash_name_len, CXS_HASH_PREFIX"%d", hash);
+
+ list_for_each_entry(tmp_lf, &cxs_long_filename_list, list) {
+ if (!strcmp(tmp_lf->name, lf->name)) {
+ kfree(lf->hash_name);
+ kfree(lf->name);
+ kfree(lf);
+ return tmp_lf->hash_name;
+ }
+ if (!strcmp(tmp_lf->hash_name, lf->hash_name)) {
+ hash += 1;
+ snprintf(lf->hash_name, sizeof(hash_name_len), CXS_HASH_PREFIX"%d", hash);
+ }
+ }
+ printk("%s:%d, hash %s\n", __func__, __LINE__, lf->hash_name);
+ list_add_tail(&lf->list, &cxs_long_filename_list);
+
+ return lf->hash_name;
+}
+EXPORT_SYMBOL(cxs_hash_filename);
+
+static struct file *cxs_open_file(const char *filename)
+{
+ struct file *filp;
+ filp = filp_open(filename, O_CREAT | O_RDWR, 0666);
+ if (IS_ERR(filp))
+ printk("failed to open %s\n", filename);
+ return filp;
+}
+
+static bool cxs_read_hash_file(const char *filename, char *buffer, size_t len)
+{
+ bool ret = true;
+ ssize_t res;
+ struct file *filp;
+
+ filp = cxs_open_file(filename);
+ if (IS_ERR(filp)) {
+ ret = false;
+ goto out;
+ }
+
+ filp->f_pos = 0;
+ // oldfs = get_fs(); set_fs(get_ds()); res = vfs_read(filp, buffer, len, &filp->f_pos); set_fs(oldfs);
+ res = kernel_read(filp, buffer, len, &filp->f_pos);
+ if (res <= 0) {
+ ret = false;
+ printk("failed to read from %s\n", filename);
+ goto out;
+ }
+ printk("successful read from %s\n", filename);
+out:
+ filp_close(filp, NULL);
+ return ret;
+}
+
+static bool cxs_write_hash_file(const char *filename, char *buffer, size_t len)
+{
+ bool ret = true;
+ ssize_t res;
+ struct file *filp;
+
+ filp = cxs_open_file(filename);
+ if (IS_ERR(filp)) {
+ ret = false;
+ goto out;
+ }
+
+ filp->f_pos = 0;
+ res = kernel_write(filp, buffer, len, &filp->f_pos);
+ if (res <= 0) {
+ ret = false;
+ printk("failed to write to %s\n", filename);
+ goto out;
+ }
+ printk("successful write to %s\n", filename);
+out:
+ filp_close(filp, NULL);
+ return ret;
+}
+
+void cxs_hash_filename2(const char *name, const char *hash_name, unsigned int hash_name_len)
+{
+ unsigned int hash;
+ char buffer[CXS_FILENAME_MAXLEN + 1];
+ char hash_file_name[hash_name_len + 1];
+ hash = simple_hash(name); // or use full_name_hash ?
+ snprintf(hash_name, hash_name_len, CXS_HASH_PREFIX"%d", hash);
+ snprintf(hash_file_name, sizeof(hash_file_name), "/.%s", hash_name); // TODO: 在挂载点下创建文件
+
+ while (1) {
+ // TODO: 文件打开失败的错误处理
+ if (cxs_read_hash_file(hash_file_name, buffer, sizeof(buffer))) { // 文件里面有内容
+ if (!strcmp(name, buffer)) // 原文件名一样
+ return;
+ // 原文件名不一样
+ hash += 1;
+ snprintf(hash_name, sizeof(hash_name), CXS_HASH_PREFIX"%d", hash);
+ snprintf(hash_file_name, sizeof(hash_file_name), "/.%s%d", hash_name, hash); // TODO: 在挂载点下创建文件
+ } else {
+ printk("will write to %s\n", hash_file_name);
+ cxs_write_hash_file(hash_file_name, name, strlen(name) + 1);
+ return;
+ }
+ }
+}
+EXPORT_SYMBOL(cxs_hash_filename2);
+
+char *cxs_unhash_filename(const char *hash_name)
+{
+ struct cxs_long_filename *lf;
+ printk("%s:%d, unhash %s\n", __func__, __LINE__, hash_name);
+ list_for_each_entry(lf, &cxs_long_filename_list, list) {
+ if (!strcmp(lf->hash_name, hash_name))
+ break;
+ }
+ return lf->name;
+}
+EXPORT_SYMBOL(cxs_unhash_filename);
+
+void cxs_unhash_filename2(const char *hash_name, const char *name, unsigned int name_len)
+{
+ char hash_file_name[CXS_HASH_NAME_LEN + 1];
+ snprintf(hash_file_name, sizeof(hash_file_name), "/.%s", hash_name); // TODO: 在挂载点下查找文件
+ // TODO: 文件打开失败的错误处理
+ cxs_read_hash_file(hash_file_name, name, name_len);
+ printk("unhash %s to %s\n", hash_name, name);
+}
+EXPORT_SYMBOL(cxs_unhash_filename2);
+
struct filename *
getname_uflags(const char __user *filename, int uflags)
{
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 1fbc72c5f112..b00bf30d9236 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2628,6 +2628,14 @@ extern int filp_close(struct file *, fl_owner_t id);
extern struct filename *getname_flags(const char __user *, int, int *);
extern struct filename *getname_uflags(const char __user *, int);
extern struct filename *getname(const char __user *);
+#define CXS_HASH_PREFIX "cxs_hash"
+#define CXS_HASH_NAME_LEN (strlen(CXS_HASH_PREFIX) + 65)
+#define CXS_FILENAME_MAXLEN 4095
+#define CXS_SHORT_FILENAME_MAXLEN 255
+extern char *cxs_hash_filename(const char *name);
+extern char *cxs_unhash_filename(const char *hash_name);
+extern void cxs_hash_filename2(const char *name, const char *hash_name, unsigned int hash_name_len);
+extern void cxs_unhash_filename2(const char *hash_name, const char *name, unsigned int name_len);
extern struct filename *getname_kernel(const char *);
extern void putname(struct filename *name);
--
2.34.1
此处可能存在不合适展示的内容，页面不予展示。您可通过相关编辑功能自查并修改。
如您确认内容无涉及 不当用语 / 纯广告导流 / 暴力 / 低俗色情 / 侵权 / 盗版 / 虚假 / 无价值内容或违法国家有关法律法规的内容，可点击提交进行申诉，我们将尽快为您处理。
马建仓 AI 助手
