New upstream version 1.2.5
[sven/exfat-utils.git] / libexfat / node.c
index fa04e25..90002eb 100644 (file)
@@ -30,7 +30,6 @@ struct iterator
 {
        cluster_t cluster;
        off_t offset;
-       int contiguous;
        char* chunk;
 };
 
@@ -95,21 +94,35 @@ static off_t co2o(struct exfat* ef, cluster_t cluster, off_t offset)
 static int opendir(struct exfat* ef, const struct exfat_node* dir,
                struct iterator* it)
 {
+       char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+
        if (!(dir->flags & EXFAT_ATTRIB_DIR))
-               exfat_bug("not a directory");
+       {
+               exfat_get_name(dir, buffer, sizeof(buffer) - 1);
+               exfat_bug("'%s' is not a directory", buffer);
+       }
+       if (CLUSTER_INVALID(dir->start_cluster))
+       {
+               exfat_get_name(dir, buffer, sizeof(buffer) - 1);
+               exfat_error("'%s' directory starts with invalid cluster %#x", buffer,
+                               dir->start_cluster);
+               return -EIO;
+       }
        it->cluster = dir->start_cluster;
        it->offset = 0;
-       it->contiguous = IS_CONTIGUOUS(*dir);
        it->chunk = malloc(CLUSTER_SIZE(*ef->sb));
        if (it->chunk == NULL)
        {
-               exfat_error("out of memory");
+               exfat_error("failed to allocate memory for directory cluster");
                return -ENOMEM;
        }
        if (exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
                        exfat_c2o(ef, it->cluster)) < 0)
        {
-               exfat_error("failed to read directory cluster %#x", it->cluster);
+               free(it->chunk);
+               exfat_get_name(dir, buffer, sizeof(buffer) - 1);
+               exfat_error("failed to read '%s' directory cluster %#x", buffer,
+                               it->cluster);
                return -EIO;
        }
        return 0;
@@ -119,7 +132,6 @@ static void closedir(struct iterator* it)
 {
        it->cluster = 0;
        it->offset = 0;
-       it->contiguous = 0;
        free(it->chunk);
        it->chunk = NULL;
 }
@@ -194,9 +206,10 @@ static const struct exfat_entry* get_entry_ptr(const struct exfat* ef,
 }
 
 static bool check_node(const struct exfat_node* node, uint16_t actual_checksum,
-               uint16_t reference_checksum, uint64_t valid_size)
+               uint16_t reference_checksum, uint64_t valid_size, int cluster_size)
 {
        char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+       bool ret = true;
 
        /*
           Validate checksum first. If it's invalid all other fields probably
@@ -207,7 +220,7 @@ static bool check_node(const struct exfat_node* node, uint16_t actual_checksum,
                exfat_get_name(node, buffer, sizeof(buffer) - 1);
                exfat_error("'%s' has invalid checksum (%#hx != %#hx)", buffer,
                                actual_checksum, reference_checksum);
-               return false;
+               ret = false;
        }
 
        /*
@@ -221,10 +234,49 @@ static bool check_node(const struct exfat_node* node, uint16_t actual_checksum,
                exfat_get_name(node, buffer, sizeof(buffer) - 1);
                exfat_error("'%s' has valid size (%"PRIu64") greater than size "
                                "(%"PRIu64")", buffer, valid_size, node->size);
-               return false;
+               ret = false;
        }
 
-       return true;
+       /*
+          Empty file must have zero start cluster. Non-empty file must start
+          with a valid cluster. Directories cannot be empty (i.e. must always
+          have a valid start cluster), but we will check this later in opendir()
+          to give user a chance to read current directory.
+       */
+       if (node->size == 0 && node->start_cluster != EXFAT_CLUSTER_FREE)
+       {
+               exfat_get_name(node, buffer, sizeof(buffer) - 1);
+               exfat_error("'%s' is empty but start cluster is %#x", buffer,
+                               node->start_cluster);
+               ret = false;
+       }
+       if (node->size > 0 && CLUSTER_INVALID(node->start_cluster))
+       {
+               exfat_get_name(node, buffer, sizeof(buffer) - 1);
+               exfat_error("'%s' points to invalid cluster %#x", buffer,
+                               node->start_cluster);
+               ret = false;
+       }
+
+       /* Empty file or directory must be marked as non-contiguous. */
+       if (node->size == 0 && (node->flags & EXFAT_ATTRIB_CONTIGUOUS))
+       {
+               exfat_get_name(node, buffer, sizeof(buffer) - 1);
+               exfat_error("'%s' is empty but marked as contiguous (%#x)", buffer,
+                               node->flags);
+               ret = false;
+       }
+
+       /* Directory size must be aligned on at cluster boundary. */
+       if ((node->flags & EXFAT_ATTRIB_DIR) && node->size % cluster_size != 0)
+       {
+               exfat_get_name(node, buffer, sizeof(buffer) - 1);
+               exfat_error("'%s' directory size %"PRIu64" is not divisible by %d", buffer,
+                               node->size, cluster_size);
+               ret = false;
+       }
+
+       return ret;
 }
 
 static void decompress_upcase(uint16_t* output, const le16_t* source,
@@ -340,21 +392,6 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
                        init_node_meta2(*node, meta2);
                        actual_checksum = exfat_add_checksum(entry, actual_checksum);
                        valid_size = le64_to_cpu(meta2->valid_size);
-                       /* empty files must be marked as non-contiguous */
-                       if ((*node)->size == 0 && (meta2->flags & EXFAT_FLAG_CONTIGUOUS))
-                       {
-                               exfat_error("empty file marked as contiguous (0x%hhx)",
-                                               meta2->flags);
-                               goto error;
-                       }
-                       /* directories must be aligned on at cluster boundary */
-                       if (((*node)->flags & EXFAT_ATTRIB_DIR) &&
-                               (*node)->size % CLUSTER_SIZE(*ef->sb) != 0)
-                       {
-                               exfat_error("directory has invalid size %"PRIu64" bytes",
-                                               (*node)->size);
-                               goto error;
-                       }
                        --continuations;
                        break;
 
@@ -375,7 +412,7 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
                        if (--continuations == 0)
                        {
                                if (!check_node(*node, actual_checksum, reference_checksum,
-                                               valid_size))
+                                               valid_size, CLUSTER_SIZE(*ef->sb)))
                                        goto error;
                                if (!fetch_next_entry(ef, parent, it))
                                        goto error;