Basic db impl

firmware/Cargo.toml

@@ -1,3 +1,4 @@
 [workspace]
 resolver = "3"
 members = ["acid-firmware", "password-hash"]
+default-members = []

firmware/acid-firmware/.cargo/config.toml

@@ -16,8 +16,7 @@ rustflags = [
   # "-C", "force-frame-pointers",
 ]
 
-
-[env]
+[env] # These must be kept in sync with /.zed/settings.json
 EXPLICITLY_INCLUDE_DEFAULT_DIRS = "true"
 LIBXKBCOMMON_BUILD_DIR = "../libxkbcommon/build"
 SPECTRE_API_BUILD_DIR = "../spectre-api-c/build-esp32s3"

firmware/acid-firmware/src/db/mod.rs

@@ -0,0 +1,276 @@
+use core::{
+    iter::Chain,
+    ops::{Deref, DerefMut, Range},
+};
+
+use alloc::{borrow::Cow, boxed::Box, vec::Vec};
+use ekv::{Database, flash::PageID};
+use embassy_embedded_hal::{adapter::BlockingAsync, flash::partition::Partition};
+use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
+use embedded_storage_async::nor_flash::{NorFlash, ReadNorFlash};
+use esp_hal::rng::Trng;
+use esp_storage::FlashStorage;
+use log::info;
+
+pub type PartitionAcid =
+    Partition<'static, CriticalSectionRawMutex, BlockingAsync<FlashStorage<'static>>>;
+
+// Workaround for alignment requirements.
+#[repr(C, align(4))]
+struct AlignedBuf<const N: usize>(pub [u8; N]);
+
+pub struct EkvFlash<T> {
+    flash: T,
+    buffer: Box<AlignedBuf<{ ekv::config::PAGE_SIZE }>>,
+}
+
+impl<T> EkvFlash<T> {
+    fn new(flash: T) -> Self {
+        Self {
+            flash,
+            buffer: {
+                // Allocate the buffer directly on the heap.
+                let buffer = Box::new_zeroed();
+                unsafe { buffer.assume_init() }
+            },
+        }
+    }
+}
+
+impl<T> Deref for EkvFlash<T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        &self.flash
+    }
+}
+
+impl<T> DerefMut for EkvFlash<T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.flash
+    }
+}
+
+impl<T: NorFlash + ReadNorFlash> ekv::flash::Flash for EkvFlash<T> {
+    type Error = T::Error;
+
+    fn page_count(&self) -> usize {
+        ekv::config::MAX_PAGE_COUNT
+    }
+
+    async fn erase(
+        &mut self,
+        page_id: PageID,
+    ) -> Result<(), <EkvFlash<T> as ekv::flash::Flash>::Error> {
+        self.flash
+            .erase(
+                (page_id.index() * ekv::config::PAGE_SIZE) as u32,
+                ((page_id.index() + 1) * ekv::config::PAGE_SIZE) as u32,
+            )
+            .await
+    }
+
+    async fn read(
+        &mut self,
+        page_id: PageID,
+        offset: usize,
+        data: &mut [u8],
+    ) -> Result<(), <EkvFlash<T> as ekv::flash::Flash>::Error> {
+        let address = page_id.index() * ekv::config::PAGE_SIZE + offset;
+        self.flash
+            .read(address as u32, &mut self.buffer.0[..data.len()])
+            .await?;
+        data.copy_from_slice(&self.buffer.0[..data.len()]);
+        Ok(())
+    }
+
+    async fn write(
+        &mut self,
+        page_id: PageID,
+        offset: usize,
+        data: &[u8],
+    ) -> Result<(), <EkvFlash<T> as ekv::flash::Flash>::Error> {
+        let address = page_id.index() * ekv::config::PAGE_SIZE + offset;
+        self.buffer.0[..data.len()].copy_from_slice(data);
+        self.flash
+            .write(address as u32, &self.buffer.0[..data.len()])
+            .await
+    }
+}
+
+pub struct AcidDatabase {
+    db: Database<EkvFlash<PartitionAcid>, esp_sync::RawMutex>,
+}
+
+impl Deref for AcidDatabase {
+    type Target = Database<EkvFlash<PartitionAcid>, esp_sync::RawMutex>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.db
+    }
+}
+
+impl DerefMut for AcidDatabase {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.db
+    }
+}
+
+impl AcidDatabase {
+    pub async fn mount(flash: PartitionAcid) -> AcidDatabase {
+        let mut db_config = ekv::Config::default();
+        db_config.random_seed = Trng::try_new()
+            .expect("A `TrngSource` was not initialized before constructing this `Trng`.")
+            .random();
+        let db = Database::<_, esp_sync::RawMutex>::new(EkvFlash::new(flash), db_config);
+
+        #[cfg(feature = "format-db")]
+        {
+            warn!("Formatting EKV database...");
+            db.format()
+                .await
+                .unwrap_or_else(|error| panic!("Failed to format the EKV database: {error:?}"));
+            warn!("EKV database formatted successfully.");
+        }
+
+        match db.mount().await {
+            Ok(()) => info!("EKV database mounted."),
+            Err(error) => panic!("Failed to mount the EKV database: {error:?}"),
+        };
+
+        Self { db }
+    }
+}
+
+type DbPathSegment<'a> = Cow<'a, str>;
+type DbPathBuf<'a> = Vec<DbPathSegment<'a>>;
+type DbPath<'a> = [DbPathSegment<'a>];
+
+struct DbKey(Vec<u8>);
+
+impl Deref for DbKey {
+    type Target = [u8];
+
+    fn deref(&self) -> &Self::Target {
+        &self.0[0..(self.0.len() - 2)]
+    }
+}
+
+impl DbKey {
+    fn from_raw(mut key: Vec<u8>) -> Self {
+        key.extend_from_slice(&[0, 1]);
+        Self(key)
+    }
+
+    fn new<'a>(path: impl IntoIterator<Item = DbPathSegment<'a>>) -> Self {
+        // Null bytes are not allowed within path segments, and will cause a panic.
+        // The segments are separated by `[0, 0]`.
+        // Two null-bytes are used to allow for easy range lookups by suffixing the key with:
+        // `[0]..[0, 1]`
+        // To avoid reallocations, we always suffix the key with `[0, 1]`.
+        // Then, a specific key can be looked up using by omitting the last two bytes.
+        // By omitting one byte, you get the start of the range of all paths within this path.
+        // By not omitting any bytes, you get the end of that range.
+
+        let mut bytes = Vec::new();
+
+        for segment in path {
+            assert!(
+                !segment.as_bytes().contains(&0x00),
+                "A path segment must not contain null bytes."
+            );
+
+            bytes.extend_from_slice(segment.as_bytes());
+            bytes.extend_from_slice(&[0, 0]);
+        }
+
+        if let Some(last_byte) = bytes.last_mut() {
+            *last_byte = 1;
+        } else {
+            panic!("An empty path is not a valid path.");
+        }
+
+        DbKey(bytes)
+    }
+
+    fn range_of_children(&self) -> Range<&[u8]> {
+        (&self.0[0..(self.0.len() - 1)])..(&self.0[..])
+    }
+
+    fn segments(&self) -> impl Iterator<Item = DbPathSegment<'_>> {
+        struct SegmentIterator<'a> {
+            rest: &'a [u8],
+        }
+
+        impl<'a> Iterator for SegmentIterator<'a> {
+            type Item = DbPathSegment<'a>;
+
+            fn next(&mut self) -> Option<Self::Item> {
+                if let Some(end_index) = self.rest.iter().position(|byte| *byte == 0) {
+                    let segment = &self.rest[..end_index];
+                    let segment = str::from_utf8(segment).unwrap();
+                    self.rest = &self.rest[end_index + 2..];
+
+                    Some(Cow::Borrowed(segment))
+                } else {
+                    None
+                }
+            }
+        }
+
+        SegmentIterator {
+            rest: self.0.as_slice(),
+        }
+    }
+}
+
+pub struct DbPathSpectreUsers;
+
+impl<'a> IntoIterator for DbPathSpectreUsers {
+    type Item = DbPathSegment<'static>;
+    type IntoIter = core::array::IntoIter<DbPathSegment<'static>, 2>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        [
+            DbPathSegment::Borrowed("spectre"),
+            DbPathSegment::Borrowed("users"),
+        ]
+        .into_iter()
+    }
+}
+
+pub struct DbPathSpectreUserSites<'a> {
+    username: DbPathSegment<'a>,
+}
+
+impl<'a> IntoIterator for DbPathSpectreUserSites<'a> {
+    type Item = DbPathSegment<'a>;
+    type IntoIter = core::array::IntoIter<DbPathSegment<'a>, 4>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        [
+            DbPathSegment::Borrowed("spectre"),
+            DbPathSegment::Borrowed("user"),
+            self.username,
+            DbPathSegment::Borrowed("site"),
+        ]
+        .into_iter()
+    }
+}
+
+pub struct DbPathSpectreUserSite<'a> {
+    user_sites: DbPathSpectreUserSites<'a>,
+    site: DbPathSegment<'a>,
+}
+
+impl<'a> IntoIterator for DbPathSpectreUserSite<'a> {
+    type Item = DbPathSegment<'a>;
+    type IntoIter =
+        Chain<core::array::IntoIter<DbPathSegment<'a>, 4>, core::iter::Once<DbPathSegment<'a>>>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.user_sites
+            .into_iter()
+            .chain(core::iter::once(self.site))
+    }
+}

firmware/acid-firmware/src/main.rs

@@ -77,6 +77,7 @@ use crate::vial::{CustomKeycodes, VIAL_KEYBOARD_DEF, VIAL_KEYBOARD_ID};
 mutually_exclusive_features::none_or_one_of!["usb-log", "alt-log", "rtt-log"];
 
 mod crypto;
+mod db;
 mod ffi;
 mod keymap;
 mod logging;

firmware/acid-firmware/src/ui/mod.rs

@@ -1,8 +1,11 @@
 // #![cfg_attr(not(feature = "simulator"), no_main)]
 
-use core::ops::{Deref, DerefMut};
+use core::{
+    iter::Chain,
+    ops::{Deref, DerefMut, Range},
+};
 
-use alloc::{boxed::Box, ffi::CString};
+use alloc::{borrow::Cow, boxed::Box, ffi::CString, vec::Vec};
 use ekv::{Database, MountError, flash::PageID};
 use embassy_embedded_hal::{adapter::BlockingAsync, flash::partition::Partition};
 use embassy_sync::blocking_mutex::raw::{CriticalSectionRawMutex, RawMutex};
@@ -10,6 +13,7 @@ use embassy_time::{Duration, Instant};
 use embedded_storage_async::nor_flash::{NorFlash, ReadNorFlash};
 use esp_hal::rng::Trng;
 use esp_storage::FlashStorage;
+use itertools::Itertools;
 use log::{info, warn};
 use rmk::futures::TryFutureExt;
 use slint::SharedString;
@@ -17,120 +21,26 @@ use spectre_api_sys::{SpectreAlgorithm, SpectreCounter, SpectreKeyPurpose, Spect
 
 #[cfg(feature = "limit-fps")]
 use crate::FRAME_DURATION_MIN;
-use crate::{SIGNAL_LCD_SUBMIT, SIGNAL_UI_RENDER, ui::backend::SlintBackend, util::DurationExt};
+use crate::{
+    SIGNAL_LCD_SUBMIT, SIGNAL_UI_RENDER,
+    db::{AcidDatabase, PartitionAcid},
+    ui::backend::SlintBackend,
+    util::DurationExt,
+};
 
 pub mod backend;
 pub mod window_adapter;
 
 slint::include_modules!();
 
-type PartitionAcid =
-    Partition<'static, CriticalSectionRawMutex, BlockingAsync<FlashStorage<'static>>>;
-
-// Workaround for alignment requirements.
-#[repr(C, align(4))]
-struct AlignedBuf<const N: usize>(pub [u8; N]);
-
-struct EkvFlash<T> {
-    flash: T,
-    buffer: Box<AlignedBuf<{ ekv::config::PAGE_SIZE }>>,
-}
-
-impl<T> EkvFlash<T> {
-    fn new(flash: T) -> Self {
-        Self {
-            flash,
-            buffer: {
-                // Allocate the buffer directly on the heap.
-                let buffer = Box::new_zeroed();
-                unsafe { buffer.assume_init() }
-            },
-        }
-    }
-}
-
-impl<T> Deref for EkvFlash<T> {
-    type Target = T;
-
-    fn deref(&self) -> &Self::Target {
-        &self.flash
-    }
-}
-
-impl<T> DerefMut for EkvFlash<T> {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut self.flash
-    }
-}
-
-impl<T: NorFlash + ReadNorFlash> ekv::flash::Flash for EkvFlash<T> {
-    type Error = T::Error;
-
-    fn page_count(&self) -> usize {
-        ekv::config::MAX_PAGE_COUNT
-    }
-
-    async fn erase(
-        &mut self,
-        page_id: PageID,
-    ) -> Result<(), <EkvFlash<T> as ekv::flash::Flash>::Error> {
-        self.flash
-            .erase(
-                (page_id.index() * ekv::config::PAGE_SIZE) as u32,
-                ((page_id.index() + 1) * ekv::config::PAGE_SIZE) as u32,
-            )
-            .await
-    }
-
-    async fn read(
-        &mut self,
-        page_id: PageID,
-        offset: usize,
-        data: &mut [u8],
-    ) -> Result<(), <EkvFlash<T> as ekv::flash::Flash>::Error> {
-        let address = page_id.index() * ekv::config::PAGE_SIZE + offset;
-        self.flash
-            .read(address as u32, &mut self.buffer.0[..data.len()])
-            .await?;
-        data.copy_from_slice(&self.buffer.0[..data.len()]);
-        Ok(())
-    }
-
-    async fn write(
-        &mut self,
-        page_id: PageID,
-        offset: usize,
-        data: &[u8],
-    ) -> Result<(), <EkvFlash<T> as ekv::flash::Flash>::Error> {
-        let address = page_id.index() * ekv::config::PAGE_SIZE + offset;
-        self.buffer.0[..data.len()].copy_from_slice(data);
-        self.flash
-            .write(address as u32, &self.buffer.0[..data.len()])
-            .await
-    }
-}
-
 #[embassy_executor::task]
 pub async fn run_renderer_task(backend: SlintBackend, flash_part_acid: PartitionAcid) {
-    let mut db_config = ekv::Config::default();
-    db_config.random_seed = Trng::try_new()
-        .expect("A `TrngSource` was not initialized before constructing this `Trng`.")
-        .random();
-    let mut db = Database::<_, esp_sync::RawMutex>::new(EkvFlash::new(flash_part_acid), db_config);
+    let db = AcidDatabase::mount(flash_part_acid).await;
+    let write = db.write_transaction().await;
 
-    #[cfg(feature = "format-db")]
-    {
-        warn!("Formatting EKV database...");
-        db.format()
-            .await
-            .unwrap_or_else(|error| panic!("Failed to format the EKV database: {error:?}"));
-        warn!("EKV database formatted successfully.");
-    }
-
-    match db.mount().await {
-        Ok(()) => info!("EKV database mounted."),
-        Err(error) => panic!("Failed to mount the EKV database: {error:?}"),
-    };
+    // TODO:
+    // * Store a config as a versioned postcard-serialized struct
+    // * Store accounts and sites as ranges in the DB
 
     slint::platform::set_platform(Box::new(backend)).expect("backend already initialized");