view target-utils/libtiffs/findfile.c @ 921:74d284add54d

fc-fsio: guard against bogus readdir results from the target If the FFS being operated on contains SE K2x0 extended filenames, readdir will return strings that are bad for printing. We need to guard against this possibility, and also against possible other bogosity that could be sent by other alien firmwares.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 31 Dec 2022 22:55:23 +0000
parents 87cb03b35f77
children
line wrap: on
line source

#include <sys/types.h>
#include "types.h"
#include "struct.h"
#include "globals.h"
#include "macros.h"

static u8 *
find_endofchunk(ino)
{
	struct inode *irec = tiffs_active_index + ino;
	u8 *p;
	int i;

	p = inode_to_dataptr(irec) + irec->len;
	for (i = 0; i < 16; i++) {
		p--;
		if (!*p)
			return(p);
		if (*p != 0xFF)
			break;
	}
	printf("Error: inode #%x has no valid termination\n", ino);
	return(p);	/* XXX */
}

tiffs_find_file(pathname, startret, sizeret, continue_ret)
	char *pathname;
	u8 **startret;
	size_t *sizeret;
	int *continue_ret;
{
	int ino, cont;
	struct inode *irec;
	u8 *start, *end;
	int size;

	ino = tiffs_pathname_to_inode(pathname);
	if (ino <= 0)
		return(-1);
	irec = tiffs_active_index + ino;
	if (irec->type != OBJTYPE_FILE) {
		printf("Error: %s is not a regular file\n", pathname);
		return(-1);
	}
	start = inode_to_dataptr(irec);
	start += strlen(start) + 1;
	end = find_endofchunk(ino);
	size = end - start;
	if (size < 0)
		size = 0;
	cont = irec->descend;
	if (cont == 0xFFFF)
		cont = 0;
	if (startret)
		*startret = start;
	if (sizeret)
		*sizeret = size;
	if (continue_ret)
		*continue_ret = cont;
	return(0);
}

tiffs_get_segment(ino, startret, sizeret, continue_ret)
	int ino;
	u8 **startret;
	size_t *sizeret;
	int *continue_ret;
{
	int cont;
	struct inode *irec;
	u8 *start, *end;
	int size;

	for (;;) {
		irec = tiffs_active_index + ino;
		if (irec->type)
			break;
		if (irec->sibling == 0xFFFF) {
		    printf("Error: segment inode #%d: deleted and no sibling\n",
				ino);
			return(-1);
		}
		ino = irec->sibling;
	}
	if (irec->type != OBJTYPE_SEGMENT) {
		printf("Error: inode #%x is not a segment\n", ino);
		return(-1);
	}
	start = inode_to_dataptr(irec);
	end = find_endofchunk(ino);
	size = end - start;
	if (size <= 0) {
		printf("Error: segment inode #%x: bad length\n", ino);
		return(-1);
	}
	cont = irec->descend;
	if (cont == 0xFFFF)
		cont = 0;
	if (startret)
		*startret = start;
	if (sizeret)
		*sizeret = size;
	if (continue_ret)
		*continue_ret = cont;
	return(0);
}