ds_rom/rom/
header.rs

1use std::{
2    mem::{offset_of, size_of},
3    str::FromStr,
4};
5
6use serde::{Deserialize, Serialize};
7use snafu::Snafu;
8
9use super::{
10    raw::{
11        self, AccessControl, Capacity, Delay, DsFlags, DsiFlags, DsiFlags2, HeaderVersion, ProgramOffset, RegionFlags,
12        TableOffset,
13    },
14    BuildContext, Rom,
15};
16use crate::{
17    crc::CRC_16_MODBUS,
18    str::{AsciiArray, AsciiArrayError},
19};
20/// ROM header.
21#[derive(Serialize, Deserialize, Default)]
22pub struct Header {
23    /// Values for the original header version, [`HeaderVersion::Original`].
24    #[serde(flatten)]
25    pub original: HeaderOriginal,
26    /// Values for DS games after DSi release, [`HeaderVersion::DsPostDsi`].
27    #[serde(skip_serializing_if = "Option::is_none")]
28    pub ds_post_dsi: Option<HeaderDsPostDsi>,
29}
30
31/// Values for the original header version, [`HeaderVersion::Original`].
32#[derive(Serialize, Deserialize, Default)]
33pub struct HeaderOriginal {
34    /// Short game title, normally in uppercase letters.
35    pub title: String,
36    /// 4-character game code in uppercase letters.
37    pub gamecode: AsciiArray<4>,
38    /// 2-character maker code, normally "01".
39    pub makercode: AsciiArray<2>,
40    /// Unit code, depends on which platform (DS, DSi) this game is for.
41    pub unitcode: u8,
42    /// Encryption seed select.
43    pub seed_select: u8,
44    /// Flags for both DS and DSi.
45    pub ds_flags: DsFlags,
46    /// Autostart, can skip "Health and Safety" screen.
47    pub autostart: u8,
48    /// Port 0x40001a4 setting for normal commands.
49    pub normal_cmd_setting: u32,
50    /// Port 0x40001a4 setting for KEY1 commands.
51    pub key1_cmd_setting: u32,
52    /// Delay to wait for secure area.
53    pub secure_area_delay: Delay,
54    /// NAND end of ROM area in multiples of 0x20000 (0x80000 on DSi).
55    pub rom_nand_end: u16,
56    /// NAND end of RW area in multiples of 0x20000 (0x80000 on DSi).
57    pub rw_nand_end: u16,
58}
59
60/// Values for DS games after DSi release, [`HeaderVersion::DsPostDsi`].
61#[derive(Serialize, Deserialize)]
62pub struct HeaderDsPostDsi {
63    /// DSi-exclusive flags.
64    pub dsi_flags_2: DsiFlags2,
65    /// SHA1-HMAC of banner.
66    pub sha1_hmac_banner: [u8; 0x14],
67    /// Unknown SHA1-HMAC, defined by some games.
68    pub sha1_hmac_unk1: [u8; 0x14],
69    /// Unknown SHA1-HMAC, defined by some games.
70    pub sha1_hmac_unk2: [u8; 0x14],
71    /// RSA-SHA1 signature up to [`raw::Header::debug_args`].
72    pub rsa_sha1: Box<[u8]>,
73}
74
75/// Errors related to [`Header::build`].
76#[derive(Snafu, Debug)]
77pub enum HeaderBuildError {
78    /// See [`AsciiArrayError`].
79    #[snafu(transparent)]
80    AsciiArray {
81        /// Source error.
82        source: AsciiArrayError,
83    },
84}
85
86impl Header {
87    /// Loads from a raw header.
88    pub fn load_raw(header: &raw::Header) -> Self {
89        let version = header.version();
90        Self {
91            original: HeaderOriginal {
92                title: header.title.to_string(),
93                gamecode: header.gamecode,
94                makercode: header.makercode,
95                unitcode: header.unitcode,
96                seed_select: header.seed_select,
97                ds_flags: header.ds_flags,
98                autostart: header.autostart,
99                normal_cmd_setting: header.normal_cmd_setting,
100                key1_cmd_setting: header.key1_cmd_setting,
101                secure_area_delay: header.secure_area_delay,
102                rom_nand_end: header.rom_nand_end,
103                rw_nand_end: header.rw_nand_end,
104            },
105            ds_post_dsi: (version >= HeaderVersion::DsPostDsi).then_some(HeaderDsPostDsi {
106                dsi_flags_2: header.dsi_flags_2,
107                sha1_hmac_banner: header.sha1_hmac_banner,
108                sha1_hmac_unk1: header.sha1_hmac_unk1,
109                sha1_hmac_unk2: header.sha1_hmac_unk2,
110                rsa_sha1: Box::new(header.rsa_sha1),
111            }),
112        }
113    }
114
115    /// Builds a raw header.
116    ///
117    /// # Panics
118    ///
119    /// Panics if a value is missing in the `context`.
120    ///
121    /// # Errors
122    ///
123    /// This function will return an error if the title contains a non-ASCII character.
124    pub fn build(&self, context: &BuildContext, rom: &Rom) -> Result<raw::Header, HeaderBuildError> {
125        let logo = rom.header_logo().compress();
126        let arm9 = rom.arm9();
127        let arm7 = rom.arm7();
128        let arm9_offset = context.arm9_offset.expect("ARM9 offset must be known");
129        let arm7_offset = context.arm7_offset.expect("ARM7 offset must be known");
130        let mut header = raw::Header {
131            title: AsciiArray::from_str(&self.original.title)?,
132            gamecode: self.original.gamecode,
133            makercode: self.original.makercode,
134            unitcode: self.original.unitcode,
135            seed_select: self.original.seed_select,
136            capacity: Capacity::from_size(context.rom_size.expect("ROM size must be known")),
137            reserved0: [0; 7],
138            dsi_flags: DsiFlags::new(),
139            ds_flags: self.original.ds_flags,
140            rom_version: 0,
141            autostart: self.original.autostart,
142            arm9: ProgramOffset {
143                offset: arm9_offset,
144                entry: arm9.entry_function(),
145                base_addr: arm9.base_address(),
146                size: arm9.full_data().len() as u32,
147            },
148            arm7: ProgramOffset {
149                offset: arm7_offset,
150                entry: arm7.entry_function(),
151                base_addr: arm7.base_address(),
152                size: arm7.full_data().len() as u32,
153            },
154            file_names: context.fnt_offset.expect("FNT offset must be known"),
155            file_allocs: context.fat_offset.expect("FAT offset must be known"),
156            arm9_overlays: context.arm9_ovt_offset.unwrap_or_default(),
157            arm7_overlays: context.arm7_ovt_offset.unwrap_or_default(),
158            normal_cmd_setting: self.original.normal_cmd_setting,
159            key1_cmd_setting: self.original.key1_cmd_setting,
160            banner_offset: context.banner_offset.map(|b| b.offset).expect("Banner offset must be known"),
161            secure_area_crc: if let Some(key) = context.blowfish_key {
162                arm9.secure_area_crc(key, self.original.gamecode.to_le_u32())
163            } else {
164                0
165            },
166            secure_area_delay: self.original.secure_area_delay,
167            arm9_autoload_callback: context.arm9_autoload_callback.expect("ARM9 autoload callback must be known"),
168            arm7_autoload_callback: context.arm7_autoload_callback.expect("ARM7 autoload callback must be known"),
169            secure_area_disable: 0,
170            rom_size_ds: context.rom_size.expect("ROM size must be known"),
171            header_size: size_of::<raw::Header>() as u32,
172            arm9_build_info_offset: context.arm9_build_info_offset.map(|offset| offset + arm9_offset).unwrap_or(0),
173            arm7_build_info_offset: context.arm7_build_info_offset.map(|offset| offset + arm7_offset).unwrap_or(0),
174            ds_rom_region_end: 0,
175            dsi_rom_region_end: 0,
176            rom_nand_end: self.original.rom_nand_end,
177            rw_nand_end: self.original.rw_nand_end,
178            reserved1: [0; 0x18],
179            reserved2: [0; 0x10],
180            logo,
181            logo_crc: CRC_16_MODBUS.checksum(&logo),
182            header_crc: 0, // gets updated below
183            debug_rom_offset: 0,
184            debug_size: 0,
185            debug_ram_addr: 0,
186            reserved3: [0; 0x4],
187            reserved4: [0; 0x10],
188            // The below fields are for DSi only and are not supported yet
189            memory_banks_wram: [0; 5],
190            memory_banks_arm9: [0; 3],
191            memory_banks_arm7: [0; 3],
192            memory_bank_9: 0,
193            region_flags: RegionFlags::new(),
194            access_control: AccessControl::new(),
195            arm7_scfg_ext7_setting: 0,
196            dsi_flags_2: DsiFlags2::new(),
197            arm9i: ProgramOffset::default(),
198            arm7i: ProgramOffset::default(),
199            digest_ds_area: TableOffset::default(),
200            digest_dsi_area: TableOffset::default(),
201            digest_sector_hashtable: TableOffset::default(),
202            digest_block_hashtable: TableOffset::default(),
203            digest_sector_size: 0,
204            digest_sector_count: 0,
205            banner_size: 0,
206            sd_shared2_0000_size: 0,
207            sd_shared2_0001_size: 0,
208            eula_version: 0,
209            use_ratings: false,
210            rom_size_dsi: 0,
211            sd_shared2_0002_size: 0,
212            sd_shared2_0003_size: 0,
213            sd_shared2_0004_size: 0,
214            sd_shared2_0005_size: 0,
215            arm9i_build_info_offset: 0,
216            arm7i_build_info_offset: 0,
217            modcrypt_area_1: TableOffset::default(),
218            modcrypt_area_2: TableOffset::default(),
219            gamecode_rev: AsciiArray([0; 4]),
220            file_type: 0,
221            sd_public_sav_size: 0,
222            sd_private_sav_size: 0,
223            reserved5: [0; 0xb0],
224            age_ratings: [0; 0x10],
225            sha1_hmac_arm9_with_secure_area: [0; 0x14],
226            sha1_hmac_arm7: [0; 0x14],
227            sha1_hmac_digest: [0; 0x14],
228            sha1_hmac_banner: [0; 0x14],
229            sha1_hmac_arm9i: [0; 0x14],
230            sha1_hmac_arm7i: [0; 0x14],
231            sha1_hmac_unk1: [0; 0x14],
232            sha1_hmac_unk2: [0; 0x14],
233            sha1_hmac_arm9: [0; 0x14],
234            reserved6: [0; 0xa4c],
235            debug_args: [0; 0x180],
236            rsa_sha1: [0; 0x80],
237            reserved7: [0; 0x3000],
238        };
239
240        if let Some(ds_post_dsi) = &self.ds_post_dsi {
241            header.dsi_flags_2 = ds_post_dsi.dsi_flags_2;
242            header.sha1_hmac_banner = ds_post_dsi.sha1_hmac_banner;
243            header.sha1_hmac_unk1 = ds_post_dsi.sha1_hmac_unk1;
244            header.sha1_hmac_unk2 = ds_post_dsi.sha1_hmac_unk2;
245            header.rsa_sha1.copy_from_slice(&ds_post_dsi.rsa_sha1);
246        }
247
248        header.header_crc = CRC_16_MODBUS.checksum(&bytemuck::bytes_of(&header)[0..offset_of!(raw::Header, header_crc)]);
249        Ok(header)
250    }
251
252    /// Returns the version of this [`Header`].
253    pub fn version(&self) -> HeaderVersion {
254        if self.ds_post_dsi.is_some() {
255            HeaderVersion::DsPostDsi
256        } else {
257            HeaderVersion::Original
258        }
259    }
260}
ds_rom/rom/header.rs

ds_rom/rom/
header.rs
