use std::io::prelude::*; use std::fs::File; use std::path::{Path, PathBuf}; use std::io::SeekFrom; use std::os::unix::fs::FileExt; use integer_encoding::FixedInt; use std::fs::OpenOptions; use crypto::blake2b::Blake2b; use crypto::digest::Digest; use crypto::ed25519; use rand::{OsRng, Rng}; use errors::*; use sleep_file::*; use protocol::make_discovery_key; /// Abstract access to Hypercore register pub trait HyperRegister { /// Whether the register store contains the given (data) entry fn has(&self, entry_index: u64) -> Result; /// Whether the register store contains *all* known (data) entries fn has_all(&self) -> Result; /// If the contiguous range of entries is in the store fn has_range(&self, start: u64, end: u64) -> Result; /// Reads a single data entry from the store. fn get_data_entry(&mut self, entry_index: u64) -> Result>; /// Writes an entry to the store. Requires the private key to be present. fn append(&mut self, data: &[u8]) -> Result; /// Count of data entries for this register. This is the total count (highest entry index plus /// one); this particular store might be sparse. fn len(&self) -> Result; /// Total size of this register in bytes. fn len_bytes(&mut self) -> Result; /// [UNIMPLEMENTED] Intended to do a deeper merkel-tree verification of all stored data fn verify(&mut self) -> Result<()>; /// Quick sanity checks on register store robust-ness fn check(&mut self) -> Result<()>; /// Can this register be appended to? fn writable(&self) -> bool; /// Returns a single tree entry (using tree indexing, not data indexing). fn get_tree_entry(&mut self, tree_index: u64) -> Result>; } impl HyperRegister { fn hash_leaf(data: &[u8]) -> [u8; 40] { let mut buf = [0; 40]; u64::to_be(data.len() as u64).encode_fixed(&mut buf[32..40]); let mut hash = Blake2b::new(32); hash.input(&[0; 1]); hash.input(&buf[32..40]); hash.input(&data); hash.result(&mut buf[0..32]); buf } fn hash_parent(lhash: &[u8], rhash: &[u8]) -> [u8; 40] { let mut buf = [0; 40]; // TODO: check overflow let sum_size = u64::from_be(FixedInt::decode_fixed(&lhash[32..40])) + u64::from_be(FixedInt::decode_fixed(&rhash[32..40])); u64::to_be(sum_size as u64).encode_fixed(&mut buf[32..40]); let mut hash = Blake2b::new(32); hash.input(&[1; 1]); hash.input(&buf[32..40]); hash.input(&lhash[0..32]); hash.input(&rhash[0..32]); hash.result(&mut buf[0..32]); buf } /// Hashes all the tree root parents for the given entry index (data index, not tree index). pub fn hash_roots(reg: &mut HyperRegister, entry_index: u64) -> Result> { let mut buf = [0; 32]; let mut hash = Blake2b::new(32); let mut index_buf = [0; 8]; hash.input(&[2; 1]); for ri in HyperRegister::tree_root_nodes(entry_index) { u64::to_be(ri).encode_fixed(&mut index_buf); let node = reg.get_tree_entry(ri)?; hash.input(&node[0..32]); hash.input(&index_buf); hash.input(&node[32..40]); } hash.result(&mut buf); Ok(buf.to_vec()) } /// Calculates the root notes for a given length (of data entries, not tree entries) fn tree_root_nodes(data_count: u64) -> Vec { // TODO: this should be an iterator // NB: this is a relatively "hot" function, gets called (repeatedly?) on every mutation, // and potentially in inner loops of lookups. if data_count == 0 { return vec![]; } // Convert the count to a (descending) list of power-of-2 components let mut x = 0; let mut components = vec![]; while 2u64.pow(x) <= data_count { if (data_count & 2u64.pow(x)) != 0 { components.push(2u64.pow(x)); } x += 1; } components.reverse(); // Add and accumulate let mut accum = 0; let mut roots = vec![]; for x in components { roots.push(accum + (x - 1)); accum += 2 * x; } roots } /// Finds the offset of the given data chunk in the linear appended data file (not a "checked /// out" individual file) pub fn get_data_offset(reg: &mut HyperRegister, entry_index: u64) -> Result { // TODO: this is a naive (linear) implementation // log(N) would go up previous parent nodes (eg, use root_nodes()) let mut sum: u64 = 0; for i in 0..entry_index { let leaf = reg.get_tree_entry(i * 2)?; sum += u64::from_be(FixedInt::decode_fixed(&leaf[32..40])); } Ok(sum) } /// Every node has a parent, so this function won't fail unless index is over 2^62, in which /// case it would overflow and panics instead. fn tree_parent_index(tree_index: u64) -> u64 { for i in 0..62 { // find lowest-significant zero bit if (tree_index & (1 << i)) == 0 { // set that bit and clear next higher return ((tree_index | (1 << i))) & !(1 << (i + 1)); } } panic!("Parent lookup overflowed, huge index!"); } /// Calling this on a leaf node is an error, as is calling very high node numbers (> 2^62) fn tree_child_indices(tree_index: u64) -> Result<(u64, u64)> { if tree_index % 2 == 0 { bail!("Leaf tree nodes have no children"); } for i in 0..62 { // find lowest-significant zero bit... if (tree_index & (1 << i)) == 0 { // larger child has this bit high, next lower bit cleared let right = ((tree_index | (1 << i))) & !(1 << (i - 1)); // smaller child has next lower bit cleared let left = tree_index & !(1 << (i - 1)); assert!(left < right); return Ok((left, right)); } } bail!("Child lookup overflowed, huge index!"); } } #[test] fn test_tree_root_nodes() { assert_eq!(HyperRegister::tree_root_nodes(0), vec![]); assert_eq!(HyperRegister::tree_root_nodes(1), vec![0]); assert_eq!(HyperRegister::tree_root_nodes(2), vec![1]); assert_eq!(HyperRegister::tree_root_nodes(3), vec![1, 4]); assert_eq!(HyperRegister::tree_root_nodes(4), vec![3]); assert_eq!(HyperRegister::tree_root_nodes(5), vec![3, 8]); assert_eq!(HyperRegister::tree_root_nodes(6), vec![3, 9]); assert_eq!(HyperRegister::tree_root_nodes(7), vec![3, 9, 12]); assert_eq!(HyperRegister::tree_root_nodes(8), vec![7]); } #[test] fn test_tree_parent_index() { assert_eq!(HyperRegister::tree_parent_index(0), 1); assert_eq!(HyperRegister::tree_parent_index(1), 3); assert_eq!(HyperRegister::tree_parent_index(2), 1); assert_eq!(HyperRegister::tree_parent_index(3), 7); assert_eq!(HyperRegister::tree_parent_index(4), 5); assert_eq!(HyperRegister::tree_parent_index(5), 3); assert_eq!(HyperRegister::tree_parent_index(6), 5); assert_eq!(HyperRegister::tree_parent_index(7), 15); assert_eq!(HyperRegister::tree_parent_index(8), 9); assert_eq!(HyperRegister::tree_parent_index(9), 11); assert_eq!(HyperRegister::tree_parent_index(21), 19); assert_eq!(HyperRegister::tree_parent_index(22), 21); } #[test] fn test_tree_child_indices() { assert!(HyperRegister::tree_child_indices(0).is_err()); assert!(HyperRegister::tree_child_indices(1024).is_err()); assert_eq!(HyperRegister::tree_child_indices(1).unwrap(), (0, 2)); assert_eq!(HyperRegister::tree_child_indices(3).unwrap(), (1, 5)); assert_eq!(HyperRegister::tree_child_indices(5).unwrap(), (4, 6)); assert_eq!(HyperRegister::tree_child_indices(7).unwrap(), (3, 11)); assert_eq!(HyperRegister::tree_child_indices(9).unwrap(), (8, 10)); assert_eq!(HyperRegister::tree_child_indices(11).unwrap(), (9, 13)); assert_eq!(HyperRegister::tree_child_indices(13).unwrap(), (12, 14)); assert_eq!(HyperRegister::tree_child_indices(15).unwrap(), (7, 23)); assert_eq!(HyperRegister::tree_child_indices(19).unwrap(), (17, 21)); } /// Implementation of HyperRegister using a local directory of SLEEP files #[derive(Debug)] pub struct SleepDirRegister { tree_sleep: SleepFile, sign_sleep: SleepFile, bitfield_sleep: SleepFile, data_file: Option, // Except, these should be Ed25519 keys, not bytes pub_key: Vec, secret_key: Option>, path: PathBuf, prefix: String, } fn read_key_file(path: &Path, is_secret: bool) -> Result> { let expected = if is_secret { 64 } else { 32 }; let mut key = vec![]; let mut key_file = OpenOptions::new().read(true).write(false).open(path)?; key_file.read_to_end(&mut key)?; if key.len() != expected { bail!( "Bad key file (len {} != {}): {}", key.len(), expected, path.display() ); } Ok(key) } fn write_key_file(path: &Path, key: &[u8], is_secret: bool) -> Result<()> { let expected = if is_secret { 64 } else { 32 }; if key.len() != expected { bail!( "Bad key file (len {} != {}): {}", key.len(), expected, path.display() ); } let mut key_file = OpenOptions::new().write(true).create_new(true).open(path)?; key_file.write_all(&key)?; Ok(()) } impl SleepDirRegister { pub fn open(directory: &Path, prefix: &str, writable: bool) -> Result { // read public key from disk let pub_key: Vec = read_key_file( &directory.join(Path::new(&(prefix.to_owned() + ".key"))), false, )?; let mut secret_key = None; if writable { secret_key = Some(read_key_file( &directory.join(Path::new(&(prefix.to_owned() + ".secret_key"))), true, )?); } let data_path = &directory.join(Path::new(&(prefix.to_owned() + ".data"))); let data_file = if data_path.is_file() { Some(OpenOptions::new() .read(true) .write(writable) .open(data_path)?) } else { warn!("SleepDirRegister data file not found: {}", data_path.display()); None }; let tree_sleep = SleepFile::open( &directory.join(Path::new(&(prefix.to_owned() + ".tree"))), writable, )?; let sign_sleep = SleepFile::open( &directory.join(Path::new(&(prefix.to_owned() + ".signatures"))), writable, )?; let bitfield_sleep = SleepFile::open( &directory.join(Path::new(&(prefix.to_owned() + ".bitfield"))), writable, )?; let mut sf = SleepDirRegister { tree_sleep, sign_sleep, bitfield_sleep, data_file, pub_key, secret_key, path: directory.to_path_buf(), prefix: prefix.to_string(), }; sf.check()?; Ok(sf) } /// In addition to what one would expect, also creates an Ed25519 key-pair using OsRng pub fn create(directory: &Path, prefix: &str) -> Result { let mut rand_seed = vec![0; 32]; let mut rng = OsRng::new()?; rng.fill_bytes(&mut rand_seed); let (secret_key, pub_key) = ed25519::keypair(&rand_seed); write_key_file( &directory.join(Path::new(&(prefix.to_owned() + ".key"))), &pub_key, false, )?; write_key_file( &directory.join(Path::new(&(prefix.to_owned() + ".secret_key"))), &secret_key, true, )?; let data_file = OpenOptions::new() .read(true) .write(true) .create_new(true) .open(directory.join(Path::new(&(prefix.to_owned() + ".data"))))?; let tree_sleep = SleepFile::create( &directory.join(Path::new(&(prefix.to_owned() + ".tree"))), 0x05025702, 40, Some("BLAKE2b".to_string()), )?; let sign_sleep = SleepFile::create( &directory.join(Path::new(&(prefix.to_owned() + ".signatures"))), 0x05025701, 64, Some("Ed25519".to_string()), )?; let bitfield_sleep = SleepFile::create( &directory.join(Path::new(&(prefix.to_owned() + ".bitfield"))), 0x05025700, 3328, None, )?; let mut sf = SleepDirRegister { tree_sleep, sign_sleep, bitfield_sleep, data_file: Some(data_file), pub_key: pub_key.to_vec(), secret_key: Some(secret_key.to_vec()), path: directory.to_path_buf(), prefix: prefix.to_string(), }; sf.check()?; Ok(sf) } pub fn discovery_key(&self) -> Vec { make_discovery_key(&self.pub_key) } } impl HyperRegister for SleepDirRegister { /// TODO: this version only works for "dense" registers: it just checks if the index is in the /// total length, instead of using the bitfield. fn has(&self, entry_index: u64) -> Result { return Ok(entry_index < self.len()?); } fn has_all(&self) -> Result { self.has_range(0, self.len()?) } fn has_range(&self, start: u64, end: u64) -> Result { // This function is un-motivated and could be removed assert!(end > start); for i in start..end { if !self.has(i)? { return Ok(false); } } Ok(true) } fn get_data_entry(&mut self, index: u64) -> Result> { // Get metadata about chunk (offset and length) let offset = HyperRegister::get_data_offset(self, index)?; // Do we even have this chunk? if !self.has(index)? { bail!("Don't have that chunk"); } let data_file = if let Some(ref mut df) = self.data_file { df } else { bail!("No data file in this register (dir={} prefix={})", self.path.display(), self.prefix); }; let leaf = self.tree_sleep.read(index * 2)?; let data_len = u64::from_be(FixedInt::decode_fixed(&leaf[32..40])); // avoid foot-gun in development: cap at ~1 billion bytes assert!(data_len < 2u64.pow(29)); // Read chunk let mut data = vec![0; data_len as usize]; let got = data_file.read_at(&mut data, offset)?; if got != data.len() { bail!("Short file read"); } // TODO: check the hash? separate function? Ok(data) } fn get_tree_entry(&mut self, tree_index: u64) -> Result> { self.tree_sleep.read(tree_index) } fn append(&mut self, data: &[u8]) -> Result { if !self.data_file.is_some() { bail!("No data file in this register"); }; let index = self.len()?; // 1. Hash data chunk let leaf_hash = HyperRegister::hash_leaf(data); // 2. Append data to data file if let Some(ref mut df) = self.data_file { df.seek(SeekFrom::End(0))?; df.write_all(data)?; df.sync_data()?; } // 3. Add hash to tree file, update merkel tree self.tree_sleep.write(index * 2, &leaf_hash)?; let mut parent = HyperRegister::tree_parent_index(index * 2); while parent < index * 2 { let (left, right) = HyperRegister::tree_child_indices(parent)?; let (left, right) = (self.tree_sleep.read(left)?, self.tree_sleep.read(right)?); let parent_hash = HyperRegister::hash_parent(&left[0..40], &right[0..40]); self.tree_sleep.write(parent, &parent_hash[0..40])?; parent = HyperRegister::tree_parent_index(parent); } // 4. Add signature to signature file let root_hash = HyperRegister::hash_roots(self, index)?; let root_sig = ed25519::signature(&root_hash, &self.secret_key.clone().unwrap()); self.sign_sleep.append(&root_sig)?; // 5. Update bitfile Ok(index) } fn len(&self) -> Result { // Length in entry count. let tree_len = self.tree_sleep.len()?; if tree_len == 0 { Ok(0) } else if tree_len % 2 != 1 { bail!("Even number of tree file SLEEP entries"); } else { Ok((self.tree_sleep.len()? / 2) + 1) } } fn len_bytes(&mut self) -> Result { // TODO: this is a naive (linear) implementation // log(N) would go up previous parent nodes (eg, use tree_root_nodes()) let mut sum: u64 = 0; for i in 0..self.len()? { let leaf = self.get_tree_entry(i * 2)?; sum += u64::from_be(FixedInt::decode_fixed(&leaf[32..40])); } Ok(sum) } fn verify(&mut self) -> Result<()> { for i in 0..self.len()? { if let Some(_) = self.data_file { // 1. Read and hash data let data_chunk = self.get_data_entry(i)?; let leaf_recalc = HyperRegister::hash_leaf(&data_chunk); // 2. Check tree leaf hash for this chunk let leaf = self.get_tree_entry(i * 2)?; if leaf.to_vec() != leaf_recalc.to_vec() { bail!("Data chunk {} failed verification (leaf hash)", i); } } else { warn!("No simple datafile, can't verify hashes"); } // 3. Recurse up parents, hashing all parents let rehash = HyperRegister::hash_roots(self, i)?; // 4. Read and verify signature in file let sig = self.sign_sleep.read(i)?; if !ed25519::verify(&rehash, &self.pub_key, &sig) { bail!("Failed to verify signature for chunk {}", i) } } Ok(()) } fn check(&mut self) -> Result<()> { let sign_len = self.sign_sleep.len()?; let tree_len = self.tree_sleep.len()?; if (tree_len == 0) && (sign_len == 0) { return Ok(()); } if tree_len != (sign_len * 2) - 1 { bail!("Inconsistent SLEEP signature/tree file sizes"); } let computed = self.len_bytes()?; if let Some(ref df) = self.data_file { let file_size = df.metadata()?.len(); if file_size != computed { bail!("Computed vs. data file size mismatch ({} != {}; path={} prefix={})", computed, file_size, self.path.display(), self.prefix); } } Ok(()) } /// Checks if we have the secret key (such that we can append to this register) fn writable(&self) -> bool { return self.secret_key.is_some(); } } #[test] fn test_sdr_open() { let mut sdr = SleepDirRegister::open(Path::new("test-data/dat/simple/.dat/"), "metadata", false).unwrap(); // Values from 'dat log' assert!(sdr.check().is_ok()); // XXX: assert!(sdr.verify().is_ok()); assert_eq!(sdr.len().unwrap(), 3); assert_eq!(sdr.len_bytes().unwrap(), 145); let mut sdr = SleepDirRegister::open(Path::new("test-data/dat/simple/.dat/"), "content", false).unwrap(); // Values from 'dat log' assert!(sdr.check().is_ok()); // XXX: assert!(sdr.verify().is_ok()); assert_eq!(sdr.len().unwrap(), 2); assert_eq!(sdr.len_bytes().unwrap(), 204); } #[test] fn test_sdr_create() { use tempdir::TempDir; let tmp_dir = TempDir::new("geniza-test").unwrap(); let mut sdr = SleepDirRegister::create(tmp_dir.path(), "dummy").unwrap(); assert_eq!(sdr.len().unwrap(), 0); assert_eq!(sdr.len_bytes().unwrap(), 0); } #[test] fn test_sdr_append() { use tempdir::TempDir; let tmp_dir = TempDir::new("geniza-test").unwrap(); let mut sdr = SleepDirRegister::create(tmp_dir.path(), "dummy").unwrap(); sdr.append("hello world!".as_bytes()).unwrap(); assert!(sdr.check().is_ok()); assert!(sdr.verify().is_ok()); assert_eq!(sdr.len().unwrap(), 1); assert_eq!(sdr.len_bytes().unwrap(), 12); let count = 100; // TODO: make this >1000 when things are faster for _ in 0..count { sdr.append(&[1, 2, 3, 4, 5]).unwrap(); } assert!(sdr.check().is_ok()); assert!(sdr.verify().is_ok()); assert_eq!(sdr.len().unwrap(), 1 + count); assert_eq!(sdr.len_bytes().unwrap(), 12 + (count * 5)); } #[test] fn test_sdr_has() { use tempdir::TempDir; let tmp_dir = TempDir::new("geniza-test").unwrap(); let mut sdr = SleepDirRegister::create(tmp_dir.path(), "dummy").unwrap(); sdr.append("hello world!".as_bytes()).unwrap(); assert!(sdr.check().is_ok()); assert_eq!(sdr.has_all().unwrap(), true); assert_eq!(sdr.has(0).unwrap(), true); assert_eq!(sdr.has(40).unwrap(), false); }