TOMOYO: Add pathname grouping support.

This patch adds pathname grouping support, which is useful for grouping
pathnames that cannot be represented using /\{dir\}/ pattern.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 87 insertions, 13 deletions

diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c
index 62e089c50ae8..b5dbdc9ff73c 100644
--- a/security/tomoyo/common.c
+++ b/security/tomoyo/common.c
@@ -76,6 +76,49 @@ static int tomoyo_write_control(struct file *file, const char __user *buffer,
                                 const int buffer_len);
 
 /**
+ * tomoyo_parse_name_union - Parse a tomoyo_name_union.
+ *
+ * @filename: Name or name group.
+ * @ptr:      Pointer to "struct tomoyo_name_union".
+ *
+ * Returns true on success, false otherwise.
+ */
+bool tomoyo_parse_name_union(const char *filename,
+                             struct tomoyo_name_union *ptr)
+{
+        if (!tomoyo_is_correct_path(filename, 0, 0, 0))
+                return false;
+        if (filename[0] == '@') {
+                ptr->group = tomoyo_get_path_group(filename + 1);
+                ptr->is_group = true;
+                return ptr->group != NULL;
+        }
+        ptr->filename = tomoyo_get_name(filename);
+        ptr->is_group = false;
+        return ptr->filename != NULL;
+}
+
+/**
+ * tomoyo_print_name_union - Print a tomoyo_name_union.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ * @ptr:  Pointer to "struct tomoyo_name_union".
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool tomoyo_print_name_union(struct tomoyo_io_buffer *head,
+                                 const struct tomoyo_name_union *ptr)
+{
+        int pos = head->read_avail;
+        if (pos && head->read_buf[pos - 1] == ' ')
+                head->read_avail--;
+        if (ptr->is_group)
+                return tomoyo_io_printf(head, " @%s",
+                                        ptr->group->group_name->name);
+        return tomoyo_io_printf(head, " %s", ptr->filename->name);
+}
+
+/**
  * tomoyo_is_byte_range - Check whether the string isa \ooo style octal value.
  *
  * @str: Pointer to the string.
@@ -172,6 +215,33 @@ static void tomoyo_normalize_line(unsigned char *buffer)
 }
 
 /**
+ * tomoyo_tokenize - Tokenize string.
+ *
+ * @buffer: The line to tokenize.
+ * @w:      Pointer to "char *".
+ * @size:   Sizeof @w .
+ *
+ * Returns true on success, false otherwise.
+ */
+bool tomoyo_tokenize(char *buffer, char *w[], size_t size)
+{
+        int count = size / sizeof(char *);
+        int i;
+        for (i = 0; i < count; i++)
+                w[i] = "";
+        for (i = 0; i < count; i++) {
+                char *cp = strchr(buffer, ' ');
+                if (cp)
+                        *cp = '\0';
+                w[i] = buffer;
+                if (!cp)
+                        break;
+                buffer = cp + 1;
+        }
+        return i < count || !*buffer;
+}
+
+/**
  * tomoyo_is_correct_path - Validate a pathname.
  * @filename:     The pathname to check.
  * @start_type:   Should the pathname start with '/'?
@@ -1368,21 +1438,20 @@ static bool tomoyo_print_path_acl(struct tomoyo_io_buffer *head,
 {
         int pos;
         u8 bit;
-        const char *filename;
         const u32 perm = ptr->perm | (((u32) ptr->perm_high) << 16);
 
-        filename = ptr->filename->name;
         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
-                const char *msg;
                 if (!(perm & (1 << bit)))
                         continue;
                 /* Print "read/write" instead of "read" and "write". */
                 if ((bit == TOMOYO_TYPE_READ || bit == TOMOYO_TYPE_WRITE)
                     && (perm & (1 << TOMOYO_TYPE_READ_WRITE)))
                         continue;
-                msg = tomoyo_path2keyword(bit);
                 pos = head->read_avail;
-                if (!tomoyo_io_printf(head, "allow_%s %s\n", msg, filename))
+                if (!tomoyo_io_printf(head, "allow_%s ",
+                                      tomoyo_path2keyword(bit)) ||
+                    !tomoyo_print_name_union(head, &ptr->name) ||
+                    !tomoyo_io_printf(head, "\n"))
                         goto out;
         }
         head->read_bit = 0;
@@ -1405,21 +1474,18 @@ static bool tomoyo_print_path2_acl(struct tomoyo_io_buffer *head,
                                    struct tomoyo_path2_acl *ptr)
 {
         int pos;
-        const char *filename1;
-        const char *filename2;
         const u8 perm = ptr->perm;
         u8 bit;
 
-        filename1 = ptr->filename1->name;
-        filename2 = ptr->filename2->name;
         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
-                const char *msg;
                 if (!(perm & (1 << bit)))
                         continue;
-                msg = tomoyo_path22keyword(bit);
                 pos = head->read_avail;
-                if (!tomoyo_io_printf(head, "allow_%s %s %s\n", msg,
-                                      filename1, filename2))
+                if (!tomoyo_io_printf(head, "allow_%s ",
+                                      tomoyo_path22keyword(bit)) ||
+                    !tomoyo_print_name_union(head, &ptr->name1) ||
+                    !tomoyo_print_name_union(head, &ptr->name2) ||
+                    !tomoyo_io_printf(head, "\n"))
                         goto out;
         }
         head->read_bit = 0;
@@ -1682,6 +1748,8 @@ static int tomoyo_write_exception_policy(struct tomoyo_io_buffer *head)
                 return tomoyo_write_pattern_policy(data, is_delete);
         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DENY_REWRITE))
                 return tomoyo_write_no_rewrite_policy(data, is_delete);
+        if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_PATH_GROUP))
+                return tomoyo_write_path_group_policy(data, is_delete);
         return -EINVAL;
 }
 
@@ -1738,6 +1806,12 @@ static int tomoyo_read_exception_policy(struct tomoyo_io_buffer *head)
                         head->read_var2 = NULL;
                         head->read_step = 9;
                 case 9:
+                        if (!tomoyo_read_path_group_policy(head))
+                                break;
+                        head->read_var1 = NULL;
+                        head->read_var2 = NULL;
+                        head->read_step = 10;
+                case 10:
                         head->read_eof = true;
                         break;
                 default: