// SPDX-FileCopyrightText: 2022 Florian Märkl <info@florianmaerkl.de>
// SPDX-FileCopyrightText: 2014-2019 LemonBoy <thatlemon@gmail.com>
// SPDX-FileCopyrightText: 2014-2019 pancake <pancake@nopcode.org>
// SPDX-License-Identifier: LGPL-3.0-only

#include <rz_types.h>
#include <rz_util.h>
#include <rz_lib.h>
#include <rz_bin.h>
#include <string.h>
#include "../format/xbe/xbe.h"

static const char *kt_name[] = {
#include "../format/xbe/kernel.h"
};

static bool read_xbe_header(xbe_header *hdr, RzBuffer *b, ut64 off) {
	if (rz_buf_read_at(b, off, hdr->magic, sizeof(hdr->magic)) != sizeof(hdr->magic) ||
		rz_buf_read_at(b, off + 4, hdr->signature, sizeof(hdr->signature)) != sizeof(hdr->signature) ||
		!rz_buf_read_le32_at(b, off + 0x104, &hdr->base) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32), &hdr->headers_size) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 2, &hdr->image_size) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 3, &hdr->image_header_size) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 4, &hdr->timestamp) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 5, &hdr->cert_addr) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 6, &hdr->sections) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 7, &hdr->sechdr_addr) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 8, &hdr->init_flags) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 9, &hdr->ep) ||
		!rz_buf_read_le32_at(b, off + 0x104 + sizeof(ut32) * 10, &hdr->tls_addr)) {
		return false;
	}
	off += 0x104 + sizeof(ut32) * 11;
	for (size_t i = 0; i < RZ_ARRAY_SIZE(hdr->pe_data); i++) {
		if (!rz_buf_read_le32_at(b, off, &hdr->pe_data[i])) {
			return false;
		}
		off += sizeof(ut32);
	}
	return rz_buf_read_le32_at(b, off, &hdr->debug_path_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32), &hdr->debug_name_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 2, &hdr->debug_uname_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 3, &hdr->kernel_thunk_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 4, &hdr->nonkernel_import_dir_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 5, &hdr->lib_versions) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 6, &hdr->lib_versions_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 7, &hdr->kernel_lib_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 8, &hdr->xapi_lib_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 9, &hdr->padding[0]) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 10, &hdr->padding[1]);
}

static bool read_xbe_section(xbe_section *sect, RzBuffer *b, ut64 off) {
	return rz_buf_read_le32_at(b, off, &sect->flags) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32), &sect->vaddr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 2, &sect->vsize) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 3, &sect->offset) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 4, &sect->size) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 5, &sect->name_addr) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 6, &sect->refcount) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 7, &sect->padding[0]) &&
		rz_buf_read_le32_at(b, off + sizeof(ut32) * 8, &sect->padding[1]) &&
		rz_buf_read_at(b, off + sizeof(ut32) * 9, sect->digest, sizeof(sect->digest)) == sizeof(sect->digest);
}

static bool read_xbe_lib(xbe_lib *lib, RzBuffer *b, ut64 off) {
	return rz_buf_read_at(b, off, lib->name, sizeof(lib->name)) == sizeof(lib->name) &&
		rz_buf_read_le16_at(b, off + 8, &lib->major) &&
		rz_buf_read_le16_at(b, off + 8 + sizeof(ut16), &lib->minor) &&
		rz_buf_read_le16_at(b, off + 8 + sizeof(ut16) * 2, &lib->build) &&
		rz_buf_read_le16_at(b, off + 8 + sizeof(ut16) * 3, &lib->flags);
}

static bool check_buffer(RzBuffer *b) {
	ut8 magic[4];
	if (rz_buf_read_at(b, 0, magic, sizeof(magic)) == 4) {
		return !memcmp(magic, "XBEH", 4);
	}
	return false;
}

static bool load_buffer(RzBinFile *bf, RzBinObject *o, RzBuffer *buf, Sdb *sdb) {
	rz_bin_xbe_obj_t *obj = RZ_NEW(rz_bin_xbe_obj_t);
	if (!obj) {
		return false;
	}
	if (!read_xbe_header(&obj->header, buf, 0)) {
		RZ_FREE(obj);
		return false;
	}

	if ((obj->header.ep & 0xf0000000) == 0x40000000) {
		// Sega Chihiro xbe
		obj->ep_key = XBE_EP_CHIHIRO;
		obj->kt_key = XBE_KP_CHIHIRO;
	} else if ((obj->header.ep ^ XBE_EP_RETAIL) > 0x1000000) {
		// Debug xbe
		obj->ep_key = XBE_EP_DEBUG;
		obj->kt_key = XBE_KP_DEBUG;
	} else {
		// Retail xbe
		obj->ep_key = XBE_EP_RETAIL;
		obj->kt_key = XBE_KP_RETAIL;
	}
	o->bin_obj = obj;
	return true;
}

static void destroy(RzBinFile *bf) {
	RZ_FREE(bf->o->bin_obj);
}

static RzBinAddr *binsym(RzBinFile *bf, RzBinSpecialSymbol type) {
	if (!bf || !bf->buf || type != RZ_BIN_SPECIAL_SYMBOL_MAIN) {
		return NULL;
	}
	rz_bin_xbe_obj_t *obj = bf->o->bin_obj;
	RzBinAddr *ret = RZ_NEW0(RzBinAddr);
	if (!ret) {
		return NULL;
	}
	ret->vaddr = obj->header.ep ^ obj->ep_key;
	ret->paddr = ret->vaddr - obj->header.base;
	return ret;
}

static RzList /*<RzBinAddr *>*/ *entries(RzBinFile *bf) {
	const rz_bin_xbe_obj_t *obj;
	RzList *ret;
	RzBinAddr *ptr = RZ_NEW0(RzBinAddr);
	if (!bf || !bf->buf || !bf->o->bin_obj || !ptr) {
		free(ptr);
		return NULL;
	}
	ret = rz_list_new();
	if (!ret) {
		free(ptr);
		return NULL;
	}
	ret->free = free;
	obj = bf->o->bin_obj;
	ptr->vaddr = obj->header.ep ^ obj->ep_key;
	ptr->paddr = ptr->vaddr - obj->header.base;
	rz_list_append(ret, ptr);
	return ret;
}

static RzPVector /*<RzBinAddr *>*/ *sections(RzBinFile *bf) {
	rz_bin_xbe_obj_t *obj = NULL;
	xbe_header *h = NULL;
	RzPVector *ret = NULL;
	char tmp[0x100];
	int i, r;
	ut32 addr;

	if (!bf || !bf->o || !bf->o->bin_obj || !bf->buf) {
		return NULL;
	}
	obj = bf->o->bin_obj;
	h = &obj->header;
	if (h->sections < 1) {
		return NULL;
	}
	ret = rz_pvector_new(free);
	if (!ret) {
		return NULL;
	}
	if (h->sections < 1 || h->sections > 255) {
		goto out_error;
	}
	addr = h->sechdr_addr - h->base;
	if (addr > bf->size || addr + (sizeof(xbe_section) * h->sections) > bf->size) {
		goto out_error;
	}
	for (i = 0; i < h->sections; i++) {
		xbe_section sect;
		if (!read_xbe_section(&sect, bf->buf, addr + i * sizeof(xbe_section))) {
			goto out_error;
		}
		RzBinSection *item = RZ_NEW0(RzBinSection);
		ut32 name_addr = sect.name_addr - h->base;
		tmp[0] = 0;
		if (name_addr > bf->size || name_addr + sizeof(tmp) > bf->size) {
			free(item);
			goto out_error;
		}
		r = rz_buf_read_at(bf->buf, name_addr, (ut8 *)tmp, sizeof(tmp));
		if (r < 1) {
			free(item);
			goto out_error;
		}
		tmp[sizeof(tmp) - 1] = 0;
		item->name = rz_str_newf("%s.%i", tmp, i);
		item->paddr = sect.offset;
		item->vaddr = sect.vaddr;
		item->size = sect.size;
		item->vsize = sect.vsize;

		item->perm = RZ_PERM_R;
		if (sect.flags & SECT_FLAG_X) {
			item->perm |= RZ_PERM_X;
		}
		if (sect.flags & SECT_FLAG_W) {
			item->perm |= RZ_PERM_W;
		}
		rz_pvector_push(ret, item);
	}
	return ret;
out_error:
	rz_pvector_free(ret);
	return NULL;
}

/**
 * Generate a string like "<LIBNAME> <MAJOR>.<MINOR>.<BUILD>"
 * by reading an xbe_lib at the given offset.
 */
static char *describe_xbe_lib_at(RzBuffer *b, ut64 off, ut64 filesz) {
	if (off + sizeof(xbe_lib) > filesz) {
		return NULL;
	}
	xbe_lib lib;
	if (!read_xbe_lib(&lib, b, off)) {
		return NULL;
	}
	// lib.name may not be 0-terminated
	char name[9];
	RZ_STATIC_ASSERT(sizeof(name) == sizeof(lib.name) + 1);
	memcpy(name, lib.name, sizeof(lib.name));
	name[sizeof(lib.name)] = 0;
	return rz_str_newf("%s %i.%i.%i", name, lib.major, lib.minor, lib.build);
}

static RzPVector /*<char *>*/ *libs(RzBinFile *bf) {
	if (!bf || !bf->o || !bf->o->bin_obj) {
		return NULL;
	}
	rz_bin_xbe_obj_t *obj = bf->o->bin_obj;
	xbe_header *h = &obj->header;
	RzPVector *ret = rz_pvector_new(free);
	if (!ret) {
		return NULL;
	}

	// Hint: h->kernel_lib_addr and h->xapi_lib_addr also point to xbe_lib structs,
	// but in our known samples, they just point into the array below, so no need
	// to check them explicitly.

	for (ut32 i = 0; i < h->lib_versions; i++) {
		ut64 addr = h->lib_versions_addr - h->base + (i * sizeof(xbe_lib));
		char *lib = describe_xbe_lib_at(bf->buf, addr, bf->size);
		if (!lib) {
			break;
		}
		rz_pvector_push(ret, lib);
	}

	return ret;
}

static RzPVector /*<RzBinSymbol *>*/ *symbols(RzBinFile *bf) {
	rz_bin_xbe_obj_t *obj;
	xbe_header *h;
	RzPVector *ret;
	ut32 kt_addr;
	ut32 addr;

	if (!bf || !bf->o || !bf->o->bin_obj) {
		return NULL;
	}

	obj = bf->o->bin_obj;
	h = &obj->header;
	kt_addr = h->kernel_thunk_addr ^ obj->kt_key;
	ret = rz_pvector_new((RzPVectorFree)rz_bin_symbol_free);
	if (!ret) {
		return NULL;
	}
	int limit = h->sections;
	if (limit * (sizeof(xbe_section)) >= bf->size - h->sechdr_addr) {
		goto out_error;
	}
	xbe_section sect;
	bool found = false;
	for (size_t i = 0; found == false && i < limit; i++) {
		addr = h->sechdr_addr - h->base + (sizeof(xbe_section) * i);
		if (addr > bf->size || addr + sizeof(sect) > bf->size ||
			!read_xbe_section(&sect, bf->buf, addr)) {
			goto out_error;
		}
		if (kt_addr >= sect.vaddr && kt_addr < sect.vaddr + sect.vsize) {
			found = true;
		}
	}
	if (!found) {
		goto out_error;
	}
	addr = sect.offset + (kt_addr - sect.vaddr);
	ut32 thunk_addr[XBE_MAX_THUNK];
	if (addr > bf->size || addr + sizeof(thunk_addr) > bf->size) {
		goto out_error;
	}
	for (size_t i = 0; i < RZ_ARRAY_SIZE(thunk_addr); i++) {
		if (!rz_buf_read_le32_at(bf->buf, addr + i * sizeof(ut32), &thunk_addr[i])) {
			goto out_error;
		}
	}
	for (size_t i = 0; i < XBE_MAX_THUNK && thunk_addr[i]; i++) {
		RzBinSymbol *sym = RZ_NEW0(RzBinSymbol);
		if (!sym) {
			goto out_error;
		}
		const ut32 thunk_index = thunk_addr[i] ^ 0x80000000;
		// Basic sanity checks
		if (thunk_addr[i] & 0x80000000 && thunk_index > 0 && thunk_index <= XBE_MAX_THUNK) {
			sym->name = rz_str_newf("kt.%s", kt_name[thunk_index - 1]);
			sym->vaddr = (h->kernel_thunk_addr ^ obj->kt_key) + (4 * i);
			sym->paddr = sym->vaddr - h->base;
			sym->size = 4;
			sym->ordinal = i;
			rz_pvector_push(ret, sym);
		} else {
			free(sym);
		}
	}
	return ret;
out_error:
	rz_pvector_free(ret);
	return NULL;
}

static RzBinInfo *info(RzBinFile *bf) {
	rz_bin_xbe_obj_t *obj;
	RzBinInfo *ret;
	ut8 dbg_name[256];

	if (!bf || !bf->buf) {
		return NULL;
	}

	ret = RZ_NEW0(RzBinInfo);
	if (!ret) {
		return NULL;
	}

	obj = bf->o->bin_obj;

	memset(dbg_name, 0, sizeof(dbg_name));
	rz_buf_read_at(bf->buf, obj->header.debug_name_addr - obj->header.base, dbg_name, sizeof(dbg_name));
	dbg_name[sizeof(dbg_name) - 1] = 0;
	ret->file = strdup((char *)dbg_name);
	ret->bclass = strdup("program");
	ret->machine = strdup("Microsoft Xbox");
	ret->os = strdup("xbox");
	ret->type = strdup("Microsoft Xbox executable");
	ret->arch = strdup("x86");
	ret->has_va = 1;
	ret->bits = 32;
	ret->big_endian = 0;
	ret->dbg_info = 0;
	ret->lang = NULL;
	return ret;
}

static ut64 baddr(RzBinFile *bf) {
	rz_bin_xbe_obj_t *obj = bf->o->bin_obj;
	return obj->header.base;
}

RzBinPlugin rz_bin_plugin_xbe = {
	.name = "xbe",
	.desc = "Microsoft Xbox XBE plugin",
	.license = "LGPL3",
	.load_buffer = &load_buffer,
	.destroy = &destroy,
	.check_buffer = &check_buffer,
	.baddr = &baddr,
	.binsym = &binsym,
	.entries = &entries,
	.maps = &rz_bin_maps_of_file_sections,
	.sections = &sections,
	.symbols = &symbols,
	.info = &info,
	.libs = &libs,
};

#ifndef RZ_PLUGIN_INCORE
RZ_API RzLibStruct rizin_plugin = {
	.type = RZ_LIB_TYPE_BIN,
	.data = &rz_bin_plugin_xbe,
	.version = RZ_VERSION
};
#endif
