#![no_std] #![forbid(clippy::cast_ptr_alignment, trivial_casts, unconditional_recursion)] #![deny(clippy::as_conversions)] mod hbm; pub use hbm::HalfBytesMask; mod spec; pub use spec::*; /// limit maximal length of store basename const BASENAME_MAXLEN: usize = 255; /// this is a trait which implements the interface of possible inputs /// (usually byte slices) pub trait ScannerInput: AsRef<[u8]> + Sized { /// Splits the input into two at the given index. /// Afterwards self contains elements [at, len), and the returned input part contains elements [0, at). fn split_to(&mut self, at: usize) -> Self; fn finish(&mut self); } impl ScannerInput for &[u8] { fn split_to(&mut self, at: usize) -> Self { let (a, b) = self.split_at(at); *self = b; a } fn finish(&mut self) { *self = &[]; } } impl ScannerInput for &mut [u8] { fn split_to(&mut self, at: usize) -> Self { // Lifetime dance taken from `impl Write for &mut [u8]`. // Taken from crate `std`. let (a, b) = core::mem::take(self).split_at_mut(at); *self = b; a } fn finish(&mut self) { *self = &mut []; } } /// this is the primary structure of this crate /// /// it represents a scanner which scans binary slices for store references, /// and implements an iterator interfaces which returns these as byte slices. pub struct StoreRefScanner<'x, Input: 'x> { input: Input, spec: &'x StoreSpec<'x>, } impl<'x, Input> StoreRefScanner<'x, Input> where Input: ScannerInput + 'x, { pub fn new(input: Input, spec: &'x StoreSpec<'x>) -> Self { for i in [&spec.valid_hashbytes, &spec.valid_restbytes] { for j in [b'\0', b' ', b'\t', b'\n', b'/', b'\\'] { assert!(!i.contains(j)); } } Self { input, spec } } } impl<'x, Input: 'x> Iterator for StoreRefScanner<'x, Input> where Input: ScannerInput + 'x, { type Item = Input; fn next(&mut self) -> Option { let hbl: usize = self.spec.hashbytes_len.into(); 'outer: while !self.input.as_ref().is_empty() { if !self.spec.path_to_store.is_empty() { let p2sas = self.spec.path_to_store; while !self.input.as_ref().starts_with(p2sas.as_bytes()) { if self.input.as_ref().is_empty() { break 'outer; } self.input.split_to(1); } self.input.split_to(p2sas.len()); if self.input.as_ref().is_empty() { break 'outer; } } let hsep = matches!(self.input.as_ref().iter().next(), Some(b'/') | Some(b'\\')); self.input.split_to(1); if hsep && self.spec.check_rest(self.input.as_ref()) { // we have found a valid hash // rest contains the store basename and all following components // now let's search for the end // and then cut off possible following components after the basename let rlen = self .input .as_ref() .iter() .enumerate() .take(BASENAME_MAXLEN) .skip(hbl) .find(|&(_, &i)| !self.spec.valid_restbytes.contains(i)) .map(|(eosp, _)| eosp) .unwrap_or_else(|| core::cmp::min(BASENAME_MAXLEN, self.input.as_ref().len())); return Some(self.input.split_to(rlen)); } } self.input.finish(); None } } #[cfg(test)] mod tests { use super::*; extern crate alloc; use alloc::{vec, vec::Vec}; #[test] fn simple_nix2() { let drv: &[u8] = br#" Derive([("out","","r:sha256","")],[("/nix/store/2ax7bvjdfkzim69q957i0jlg0nvmapg0-util-linux-2.37.2.drv",["dev"]),("/nix/store/6b55ssmh8pzqsc4q4kw1yl3kqvr4fvqj-bash-5.1-p12.drv",["out"]),("/nix/store/fp2vx24kczlzv84avds28wyzsmrn8kyv-source.drv",["out"]),("/nix/store/s6c2lm5hpsvdwnxq9y1g3ngncghjzc3k-stdenv-linux.drv",["out"]),("/nix/store/xlnzpf4mzghi8vl0krabrgcbnqk5qjf3-pkg-config-wrapper-0.29.2.drv",["out"])],["/nix/store/03sl46khd8gmjpsad7223m32ma965vy9-fix-static.patch","/nix/store/2q3z7587yhlz0i2xvfvvap42zk5carlv-bcache-udev-modern.patch","/nix/store/9krlzvny65gdc8s7kpb6lkx8cd02c25b-default-builder.sh"],"x86_64-linux","/0g15yibzzi3rmw29gqlbms05x9dbghbvh61v1qggydvmzh3bginw/bin/bash",["-e","/nix/store/9krlzvny65gdc8s7kpb6lkx8cd02c25b-default-builder.sh"],[("buildInputs","/0sdk1r4l43yw4g6lmqdhd92vhdfhlwz3m76jxzvzsqsv63czw2km"),("builder","/0g15yibzzi3rmw29gqlbms05x9dbghbvh61v1qggydvmzh3bginw/bin/bash"),("configureFlags",""),("depsBuildBuild",""),("depsBuildBuildPropagated",""),("depsBuildTarget",""),("depsBuildTargetPropagated",""),("depsHostHost",""),("depsHostHostPropagated",""),("depsTargetTarget",""),("depsTargetTargetPropagated",""),("doCheck",""),("doInstallCheck",""),("makeFlags","PREFIX=/1rz4g4znpzjwh1xymhjpm42vipw92pr73vdgl6xs1hycac8kf2n9 UDEVLIBDIR=/1rz4g4znpzjwh1xymhjpm42vipw92pr73vdgl6xs1hycac8kf2n9/lib/udev/"),("name","bcache-tools-1.0.7"),("nativeBuildInputs","/1kw0rwgdyq9q69wmmsa5d2kap6p52b0yldbzi4w17bhcq5g5cp2f"),("out","/1rz4g4znpzjwh1xymhjpm42vipw92pr73vdgl6xs1hycac8kf2n9"),("outputHashAlgo","sha256"),("outputHashMode","recursive"),("outputs","out"),("patches","/nix/store/2q3z7587yhlz0i2xvfvvap42zk5carlv-bcache-udev-modern.patch /nix/store/03sl46khd8gmjpsad7223m32ma965vy9-fix-static.patch"),("pname","bcache-tools"),("preBuild","sed -e \"s|/bin/sh|/0g15yibzzi3rmw29gqlbms05x9dbghbvh61v1qggydvmzh3bginw/bin/sh|\" -i *.rules\n"),("preInstall","mkdir -p \"$out/sbin\" \"$out/lib/udev/rules.d\" \"$out/share/man/man8\"\n"),("prePatch","sed -e \"/INSTALL.*initramfs\\/hook/d\" \\\n -e \"/INSTALL.*initcpio\\/install/d\" \\\n -e \"/INSTALL.*dracut\\/module-setup.sh/d\" \\\n -e \"s/pkg-config/$PKG_CONFIG/\" \\\n -i Makefile\n"),("propagatedBuildInputs",""),("propagatedNativeBuildInputs",""),("src","/nix/store/6izcafvfcbz19chi7hl20834g0fa043n-source"),("stdenv","/01ncyv8bxibj0imgfvmxgqy648n697bachil6aw6i46g1jk0bbds"),("strictDeps",""),("system","x86_64-linux"),("version","1.0.7")]) "#; // we convert everything into strings because it is way easier to compare elements in error messages let refs: Vec<&str> = StoreRefScanner::new(drv, &StoreSpec::DFL_NIX2) .map(|i| core::str::from_utf8(i).unwrap()) .collect(); let refs_expect: Vec<&[u8]> = vec![ b"2ax7bvjdfkzim69q957i0jlg0nvmapg0-util-linux-2.37.2.drv", b"6b55ssmh8pzqsc4q4kw1yl3kqvr4fvqj-bash-5.1-p12.drv", b"fp2vx24kczlzv84avds28wyzsmrn8kyv-source.drv", b"s6c2lm5hpsvdwnxq9y1g3ngncghjzc3k-stdenv-linux.drv", b"xlnzpf4mzghi8vl0krabrgcbnqk5qjf3-pkg-config-wrapper-0.29.2.drv", b"03sl46khd8gmjpsad7223m32ma965vy9-fix-static.patch", b"2q3z7587yhlz0i2xvfvvap42zk5carlv-bcache-udev-modern.patch", b"9krlzvny65gdc8s7kpb6lkx8cd02c25b-default-builder.sh", b"9krlzvny65gdc8s7kpb6lkx8cd02c25b-default-builder.sh", b"2q3z7587yhlz0i2xvfvvap42zk5carlv-bcache-udev-modern.patch", b"03sl46khd8gmjpsad7223m32ma965vy9-fix-static.patch", b"6izcafvfcbz19chi7hl20834g0fa043n-source", ]; let refs_expect: Vec<&str> = refs_expect .into_iter() .map(|i| core::str::from_utf8(i).unwrap()) .collect(); assert_eq!(refs, refs_expect); } #[test] fn simple_yzix1() { // I haven't yet produced any yzix derivation which included /yzixs absolute paths... let fake: &[u8] = br#" /yzixs/4Zx1PBoft1YyAuKdhjAY1seZFHloxQ+8voHQRkRMuys: ASCII text /yzixs/dNE3yogD4JHKHzNa2t3jQMZddT8wjqlMDB0naDIFo0A: ASCII text /yzixs/FMluSVOHLc4bxX7F4lBCXafNljBnDn+rAM5HzG7k8LI: unified diff output, ASCII text /yzixs/g2G3GRL87hGEdw9cq2BZWqDQP_HeHSPRLbJ9P9KH+HI: unified diff output, ASCII text /yzixs/H08Av1ZAONwFdzVLpFQm0Sc0dvyk0sbnk82waoBig7I: ASCII text /yzixs/IndARQp+gaGDLS3K+PeyXdaRqAcCyS3EIbRXkkYjC94: unified diff output, ASCII text /yzixs/IrLPnbkEolTAuWRxkXpuvVs6Imb1iB6wUJcI+fxWwkU: POSIX shell script, ASCII text executable /yzixs/JsS_H3n3TSh2R6fiIzgOPZdjSmRkV71vGxstJJKPmr4: unified diff output, ASCII text /yzixs/LZ6pQh1x8DRxZ2IYzetBRS4LuE__IXFjpOfQPxHVwpw: unified diff output, ASCII text /yzixs/mEi2RPep9daRs0JUvwt1JsDfgYSph5sH_+_ihwn8IGQ: ASCII text /yzixs/nd4DyljinP3auDMHL_LrpsRJkWQpSHQK2jqtyyzWcBA: POSIX shell script, ASCII text executable /yzixs/nzpaknF0_ONSHtd0i_e1E3pkLF1QPeJQhAB7x9Ogo_M: unified diff output, ASCII text /yzixs/UZ3uzVUUMC1gKGLw6tg_aLFwoFrJedXB3xbhEgQOaiY: unified diff output, ASCII text /yzixs/VKyXxKTXsDGxYJ24YgbvCc1bZkA5twp3TC+Gbi4Kwd8: unified diff output, ASCII text /yzixs/VPJMl8O1xkc1LsJznpoQrCrQO0Iy+ODCPsgoUBLiRZc: unified diff output, ASCII text /yzixs/W6r1ow001ASHRj+gtRfyj9Fb_gCO_pBztX8WhYXVdIc: unified diff output, ASCII text /yzixs/xvwEcXIob_rQynUEtQiQbwaDXEobTVKEGaBMir9oH9k: unified diff output, ASCII text /yzixs/ZPvQbRJrtyeSITvW3FUZvw99hhNOO3CFqGgmWgScxcg: ASCII text "#; let refs: Vec<&str> = StoreRefScanner::new(fake, &StoreSpec::DFL_YZIX1) .map(|i| core::str::from_utf8(i).unwrap()) .collect(); let refs_expect: Vec<&[u8]> = vec![ b"4Zx1PBoft1YyAuKdhjAY1seZFHloxQ+8voHQRkRMuys", b"dNE3yogD4JHKHzNa2t3jQMZddT8wjqlMDB0naDIFo0A", b"FMluSVOHLc4bxX7F4lBCXafNljBnDn+rAM5HzG7k8LI", b"g2G3GRL87hGEdw9cq2BZWqDQP_HeHSPRLbJ9P9KH+HI", b"H08Av1ZAONwFdzVLpFQm0Sc0dvyk0sbnk82waoBig7I", b"IndARQp+gaGDLS3K+PeyXdaRqAcCyS3EIbRXkkYjC94", b"IrLPnbkEolTAuWRxkXpuvVs6Imb1iB6wUJcI+fxWwkU", b"JsS_H3n3TSh2R6fiIzgOPZdjSmRkV71vGxstJJKPmr4", b"LZ6pQh1x8DRxZ2IYzetBRS4LuE__IXFjpOfQPxHVwpw", b"mEi2RPep9daRs0JUvwt1JsDfgYSph5sH_+_ihwn8IGQ", b"nd4DyljinP3auDMHL_LrpsRJkWQpSHQK2jqtyyzWcBA", b"nzpaknF0_ONSHtd0i_e1E3pkLF1QPeJQhAB7x9Ogo_M", b"UZ3uzVUUMC1gKGLw6tg_aLFwoFrJedXB3xbhEgQOaiY", b"VKyXxKTXsDGxYJ24YgbvCc1bZkA5twp3TC+Gbi4Kwd8", b"VPJMl8O1xkc1LsJznpoQrCrQO0Iy+ODCPsgoUBLiRZc", b"W6r1ow001ASHRj+gtRfyj9Fb_gCO_pBztX8WhYXVdIc", b"xvwEcXIob_rQynUEtQiQbwaDXEobTVKEGaBMir9oH9k", b"ZPvQbRJrtyeSITvW3FUZvw99hhNOO3CFqGgmWgScxcg", ]; let refs_expect: Vec<&str> = refs_expect .into_iter() .map(|i| core::str::from_utf8(i).unwrap()) .collect(); assert_eq!(refs, refs_expect); } #[test] fn just_store() { for i in [&StoreSpec::DFL_NIX2, &StoreSpec::DFL_YZIX1] { let refs: Vec<&[u8]> = StoreRefScanner::new(i.path_to_store.as_bytes(), i).collect(); assert!(refs.is_empty()); } } }