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-rw-r--r--c/src/exec/libfs/src/imfs/imfs_eval.c638
1 files changed, 638 insertions, 0 deletions
diff --git a/c/src/exec/libfs/src/imfs/imfs_eval.c b/c/src/exec/libfs/src/imfs/imfs_eval.c
new file mode 100644
index 0000000000..eb770a58ce
--- /dev/null
+++ b/c/src/exec/libfs/src/imfs/imfs_eval.c
@@ -0,0 +1,638 @@
+/*
+ * Evaluation IMFS Node Support Routines
+ *
+ * COPYRIGHT (c) 1989-1998.
+ * On-Line Applications Research Corporation (OAR).
+ * Copyright assigned to U.S. Government, 1994.
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.OARcorp.com/rtems/license.html.
+ *
+ * $Id$
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include "imfs.h"
+#include "libio_.h"
+
+#define RTEMS_LIBIO_PERMS_RX (RTEMS_LIBIO_PERMS_SEARCH | RTEMS_LIBIO_PERMS_READ)
+#define RTEMS_LIBIO_PERMS_WX (RTEMS_LIBIO_PERMS_SEARCH | RTEMS_LIBIO_PERMS_WRITE)
+
+#define MAXSYMLINK 5
+
+int IMFS_Set_handlers(
+ rtems_filesystem_location_info_t *loc
+)
+{
+ IMFS_jnode_t *node = loc->node_access;
+
+ switch( node->type ) {
+ case IMFS_DIRECTORY:
+ loc->handlers = &dir_handlers;
+ break;
+ case IMFS_DEVICE:
+ loc->handlers = &device_handlers;
+ break;
+ case IMFS_SYM_LINK:
+ case IMFS_HARD_LINK:
+ loc->handlers = &null_handlers;
+ break;
+ case IMFS_MEMORY_FILE:
+ loc->handlers = &memfile_handlers;
+ break;
+ }
+
+ return 0;
+}
+
+/*
+ * IMFS_evaluate_permission
+ *
+ * The following routine evaluates that we have permission
+ * to do flags on the node.
+ */
+
+int IMFS_evaluate_permission(
+ rtems_filesystem_location_info_t *node,
+ int flags
+)
+{
+ uid_t st_uid;
+ gid_t st_gid;
+ IMFS_jnode_t *jnode;
+ int flags_to_test;
+
+ if (! rtems_libio_is_valid_perms( flags ) ) {
+ assert( 0 );
+ set_errno_and_return_minus_one( EIO );
+ }
+
+ jnode = node->node_access;
+
+#if defined(RTEMS_POSIX_API)
+ st_uid = geteuid();
+ st_gid = getegid();
+#else
+ st_uid = jnode->st_uid;
+ st_gid = jnode->st_gid;
+#endif
+
+ /*
+ * Check if I am owner or a group member or someone else.
+ */
+
+ flags_to_test = flags;
+
+ if ( st_uid == jnode->st_uid )
+ flags_to_test <<= 6;
+ else if ( st_gid == jnode->st_gid )
+ flags_to_test <<= 3;
+ else
+ /* must be other - do nothing */;
+
+ /*
+ * If all of the flags are set we have permission
+ * to do this.
+ */
+ if ( ( flags_to_test & jnode->st_mode) == flags_to_test )
+ return 1;
+
+ return 0;
+}
+
+/*
+ * IMFS_evaluate_hard_link
+ *
+ * The following routine evaluates a hardlink to the actual node.
+ */
+
+int IMFS_evaluate_hard_link(
+ rtems_filesystem_location_info_t *node, /* IN/OUT */
+ int flags /* IN */
+)
+{
+ IMFS_jnode_t *jnode = node->node_access;
+ int result = 0;
+
+ /*
+ * Check for things that should never happen.
+ */
+
+ if ( jnode->type != IMFS_HARD_LINK )
+ rtems_fatal_error_occurred (0xABCD0000);
+
+ /*
+ * Set the hard link value and the handlers.
+ */
+
+ node->node_access = jnode->info.hard_link.link_node;
+
+ IMFS_Set_handlers( node );
+
+ /*
+ * Verify we have the correct permissions for this node.
+ */
+
+ if (! IMFS_evaluate_permission( node, flags ) )
+ set_errno_and_return_minus_one( EACCES );
+
+ return result;
+}
+
+
+/*
+ * IMFS_evaluate_sym_link
+ *
+ * The following routine evaluates a symbolic link to the actual node.
+ */
+
+int IMFS_evaluate_sym_link(
+ rtems_filesystem_location_info_t *node, /* IN/OUT */
+ int flags /* IN */
+)
+{
+ IMFS_jnode_t *jnode = node->node_access;
+ int result = 0;
+ int i;
+
+ /*
+ * Check for things that should never happen.
+ */
+
+ if ( jnode->type != IMFS_SYM_LINK )
+ rtems_fatal_error_occurred (0xABCD0000);
+
+ if ( !jnode->Parent )
+ rtems_fatal_error_occurred( 0xBAD00000 );
+
+
+ /*
+ * Move the node_access to either the symbolic links parent or
+ * root depending on the symbolic links path.
+ */
+
+ node->node_access = jnode->Parent;
+
+ rtems_filesystem_get_sym_start_loc(
+ jnode->info.sym_link.name,
+ &i,
+ node
+ );
+
+ /*
+ * Use eval path to evaluate the path of the symbolic link.
+ */
+
+ result = IMFS_eval_path(
+ &jnode->info.sym_link.name[i],
+ flags,
+ node
+ );
+
+ IMFS_Set_handlers( node );
+
+ /*
+ * Verify we have the correct permissions for this node.
+ */
+
+ if (! IMFS_evaluate_permission( node, flags ) )
+ set_errno_and_return_minus_one( EACCES );
+
+ return result;
+}
+
+/*
+ * IMFS_evaluate_link
+ *
+ * The following routine returns the real node pointed to by a link.
+ */
+
+int IMFS_evaluate_link(
+ rtems_filesystem_location_info_t *node, /* IN/OUT */
+ int flags /* IN */
+)
+{
+ IMFS_jnode_t *jnode;
+ int result = 0;
+
+ do {
+ jnode = node->node_access;
+
+ /*
+ * Increment and check the link counter.
+ */
+
+ rtems_filesystem_link_counts ++;
+ if ( rtems_filesystem_link_counts > MAXSYMLINK ) {
+ rtems_filesystem_link_counts = 0;
+ set_errno_and_return_minus_one( ELOOP );
+ }
+
+ /*
+ * Follow the Link node.
+ */
+
+ if ( jnode->type == IMFS_HARD_LINK )
+ result = IMFS_evaluate_hard_link( node, flags );
+
+ else if (jnode->type == IMFS_SYM_LINK )
+ result = IMFS_evaluate_sym_link( node, flags );
+
+ } while ( ( result == 0 ) && ( ( jnode->type == IMFS_SYM_LINK ) ||
+ ( jnode->type == IMFS_HARD_LINK ) ) );
+
+ /*
+ * Clear link counter.
+ */
+
+ rtems_filesystem_link_counts = 0;
+
+ return result;
+}
+
+
+/*
+ * IMFS_evaluate_for_make
+ *
+ * The following routine evaluate path for a new node to be created.
+ * pathloc is returned with a pointer to the parent of the new node.
+ * name is returned with a pointer to the first character in the
+ * new node name. The parent node is verified to be a directory.
+ */
+
+int IMFS_evaluate_for_make(
+ const char *path, /* IN */
+ rtems_filesystem_location_info_t *pathloc, /* IN/OUT */
+ const char **name /* OUT */
+)
+{
+ int i = 0;
+ int len;
+ IMFS_token_types type;
+ char token[ NAME_MAX + 1 ];
+ rtems_filesystem_location_info_t newloc;
+ IMFS_jnode_t *node;
+ int done = 0;
+ int result;
+
+ /*
+ * This was filled in by the caller and is valid in the
+ * mount table.
+ */
+ node = pathloc->node_access;
+
+ /*
+ * Evaluate all tokens until we are done or an error occurs.
+ */
+
+ while( !done ) {
+
+ type = IMFS_get_token( &path[i], token, &len );
+ i += len;
+
+ if ( !pathloc->node_access )
+ set_errno_and_return_minus_one( ENOENT );
+
+ /*
+ * I cannot move out of this directory without execute permission.
+ */
+
+ if ( type != IMFS_NO_MORE_PATH )
+ if ( node->type == IMFS_DIRECTORY )
+ if (! IMFS_evaluate_permission( pathloc, RTEMS_LIBIO_PERMS_SEARCH ) )
+ set_errno_and_return_minus_one( EACCES );
+
+ node = pathloc->node_access;
+
+ switch( type ) {
+
+ case IMFS_UP_DIR:
+
+ /*
+ * Am I at the root of this mounted filesystem?
+ */
+
+ if (pathloc->node_access == pathloc->mt_entry->mt_fs_root.node_access){
+
+ /*
+ * Am I at the root of all filesystems?
+ */
+
+ if ( pathloc->node_access == rtems_filesystem_root.node_access ) {
+ break;
+
+ } else {
+ newloc = pathloc->mt_entry->mt_point_node;
+ *pathloc = newloc;
+ return (*pathloc->ops->evalformake)( &path[i-len], pathloc, name );
+ }
+ } else {
+
+ if ( !node->Parent )
+ set_errno_and_return_minus_one( ENOENT );
+
+ node = node->Parent;
+ }
+
+ pathloc->node_access = node;
+ break;
+
+ case IMFS_NAME:
+
+ if ( node->type == IMFS_HARD_LINK ) {
+
+ result = IMFS_evaluate_link( pathloc, 0 );
+ if ( result == -1 )
+ return -1;
+
+ } else if ( node->type == IMFS_SYM_LINK ) {
+
+ result = IMFS_evaluate_link( pathloc, 0 );
+
+ if ( result == -1 )
+ return -1;
+ }
+
+ node = pathloc->node_access;
+ if ( !node )
+ set_errno_and_return_minus_one( ENOTDIR );
+
+ /*
+ * Only a directory can be decended into.
+ */
+
+ if ( node->type != IMFS_DIRECTORY )
+ set_errno_and_return_minus_one( ENOTDIR );
+
+ /*
+ * If we are at a node that is a mount point. Set loc to the
+ * new fs root node and let them finish evaluating the path.
+ */
+
+ if ( node->info.directory.mt_fs != NULL ) {
+ newloc = node->info.directory.mt_fs->mt_fs_root;
+ *pathloc = newloc;
+ return (*pathloc->ops->evalformake)( &path[i-len], pathloc, name );
+ }
+
+ /*
+ * Otherwise find the token name in the present location.
+ */
+
+ node = IMFS_find_match_in_dir( node, token );
+
+ /*
+ * If there is no node we have found the name of the node we
+ * wish to create.
+ */
+
+ if ( ! node )
+ done = TRUE;
+ else
+ pathloc->node_access = node;
+
+ break;
+
+ case IMFS_NO_MORE_PATH:
+ set_errno_and_return_minus_one( EEXIST );
+ break;
+
+ case IMFS_INVALID_TOKEN:
+ set_errno_and_return_minus_one( ENAMETOOLONG );
+ break;
+
+ case IMFS_CURRENT_DIR:
+ break;
+ }
+ }
+
+ *name = &path[ i - len ];
+
+ /*
+ * We have evaluated the path as far as we can.
+ * Verify there is not any invalid stuff at the end of the name.
+ */
+
+ for( ; path[i] != '\0'; i++) {
+ if (! IMFS_is_separator( path[ i ] ) )
+ set_errno_and_return_minus_one( ENOENT );
+ }
+
+ /*
+ * Verify we can execute and write to this directory.
+ */
+
+ result = IMFS_Set_handlers( pathloc );
+
+ /*
+ * The returned node must be a directory
+ */
+ node = pathloc->node_access;
+ if ( node->type != IMFS_DIRECTORY )
+ set_errno_and_return_minus_one( ENOTDIR );
+
+ /*
+ * We must have Write and execute permission on the returned node.
+ */
+
+ if (! IMFS_evaluate_permission( pathloc, RTEMS_LIBIO_PERMS_WX ) )
+ set_errno_and_return_minus_one( EACCES );
+
+ return result;
+}
+
+
+/*
+ * IMFS_eval_path
+ *
+ * The following routine evaluate path for a node that wishes to be
+ * accessed with mode. pathloc is returned with a pointer to the
+ * node to be accessed.
+ */
+
+int IMFS_eval_path(
+ const char *pathname, /* IN */
+ int flags, /* IN */
+ rtems_filesystem_location_info_t *pathloc /* IN/OUT */
+)
+{
+ int i = 0;
+ int len;
+ IMFS_token_types type = IMFS_CURRENT_DIR;
+ char token[ NAME_MAX + 1 ];
+ rtems_filesystem_location_info_t newloc;
+ IMFS_jnode_t *node;
+ int result;
+
+ if (! rtems_libio_is_valid_perms( flags ) ) {
+ assert( 0 );
+ set_errno_and_return_minus_one( EIO );
+ }
+
+ /*
+ * This was filled in by the caller and is valid in the
+ * mount table.
+ */
+
+ node = pathloc->node_access;
+
+ /*
+ * Evaluate all tokens until we are done or an error occurs.
+ */
+
+ while( (type != IMFS_NO_MORE_PATH) && (type != IMFS_INVALID_TOKEN) ) {
+
+ type = IMFS_get_token( &pathname[i], token, &len );
+ i += len;
+
+ if ( !pathloc->node_access )
+ set_errno_and_return_minus_one( ENOENT );
+
+ /*
+ * I cannot move out of this directory without execute permission.
+ */
+ if ( type != IMFS_NO_MORE_PATH )
+ if ( node->type == IMFS_DIRECTORY )
+ if (! IMFS_evaluate_permission( pathloc, RTEMS_LIBIO_PERMS_SEARCH ) )
+ set_errno_and_return_minus_one( EACCES );
+
+ node = pathloc->node_access;
+
+ switch( type ) {
+ case IMFS_UP_DIR:
+
+ /*
+ * Am I at the root of this mounted filesystem?
+ */
+
+ if (pathloc->node_access ==
+ pathloc->mt_entry->mt_fs_root.node_access) {
+
+ /*
+ * Am I at the root of all filesystems?
+ */
+
+ if ( pathloc->node_access == rtems_filesystem_root.node_access ) {
+ break; /* Throw out the .. in this case */
+ } else {
+ newloc = pathloc->mt_entry->mt_point_node;
+ *pathloc = newloc;
+ return (*pathloc->ops->evalpath)(&(pathname[i-len]),flags,pathloc);
+ }
+ } else {
+
+ if ( !node->Parent )
+ set_errno_and_return_minus_one( ENOENT );
+
+ node = node->Parent;
+ pathloc->node_access = node;
+
+ }
+
+ pathloc->node_access = node;
+ break;
+
+ case IMFS_NAME:
+ /*
+ * If we are at a link follow it.
+ */
+
+ if ( node->type == IMFS_HARD_LINK ) {
+
+ IMFS_evaluate_hard_link( pathloc, 0 );
+
+ node = pathloc->node_access;
+ if ( !node )
+ set_errno_and_return_minus_one( ENOTDIR );
+
+ } else if ( node->type == IMFS_SYM_LINK ) {
+
+ result = IMFS_evaluate_sym_link( pathloc, 0 );
+
+ node = pathloc->node_access;
+ if ( result == -1 )
+ return -1;
+ }
+
+ /*
+ * Only a directory can be decended into.
+ */
+
+ if ( node->type != IMFS_DIRECTORY )
+ set_errno_and_return_minus_one( ENOTDIR );
+
+ /*
+ * If we are at a node that is a mount point. Set loc to the
+ * new fs root node and let them finish evaluating the path.
+ */
+
+ if ( node->info.directory.mt_fs != NULL ) {
+ newloc = node->info.directory.mt_fs->mt_fs_root;
+ *pathloc = newloc;
+ return (*pathloc->ops->evalpath)( &pathname[i-len], flags, pathloc );
+ }
+
+ /*
+ * Otherwise find the token name in the present location.
+ */
+
+ node = IMFS_find_match_in_dir( node, token );
+ if ( !node )
+ set_errno_and_return_minus_one( ENOENT );
+
+ /*
+ * Set the node access to the point we have found.
+ */
+
+ pathloc->node_access = node;
+ break;
+
+ case IMFS_NO_MORE_PATH:
+ case IMFS_CURRENT_DIR:
+ break;
+
+ case IMFS_INVALID_TOKEN:
+ set_errno_and_return_minus_one( ENAMETOOLONG );
+ break;
+
+ }
+ }
+
+ /*
+ * Only return root node if this is the base file system.
+ */
+
+ if ((pathloc->node_access == pathloc->mt_entry->mt_fs_root.node_access) &&
+ (pathloc->node_access != rtems_filesystem_root.node_access) ) {
+ newloc = pathloc->mt_entry->mt_point_node;
+ *pathloc = newloc;
+ }
+
+ result = IMFS_Set_handlers( pathloc );
+
+ /*
+ * Verify we have the correct permissions for this node.
+ */
+
+ if (! IMFS_evaluate_permission( pathloc, flags ) )
+ set_errno_and_return_minus_one( EACCES );
+
+ return result;
+}
+
+
+
+
+
+
+
+
+
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