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| 1 | +use std::collections::HashMap; |
| 2 | +use std::path::Path; |
| 3 | +use std::process::Command; |
| 4 | +use std::sync::OnceLock; |
| 5 | + |
| 6 | +use crate::util; |
| 7 | +use anyhow::{bail, Context, Result}; |
| 8 | +use fn_error_context::context; |
| 9 | +use regex::Regex; |
| 10 | +use serde::{Deserialize, Serialize}; |
| 11 | + |
| 12 | +#[derive(Serialize, Deserialize, Debug)] |
| 13 | +struct BlockDevices { |
| 14 | + blockdevices: Vec<Device>, |
| 15 | +} |
| 16 | + |
| 17 | +#[derive(Serialize, Deserialize, Debug)] |
| 18 | +struct Device { |
| 19 | + path: String, |
| 20 | + pttype: Option<String>, |
| 21 | + parttype: Option<String>, |
| 22 | + parttypename: Option<String>, |
| 23 | +} |
| 24 | + |
| 25 | +impl Device { |
| 26 | + pub(crate) fn is_esp_part(&self) -> bool { |
| 27 | + const ESP_TYPE_GUID: &str = "c12a7328-f81f-11d2-ba4b-00a0c93ec93b"; |
| 28 | + if let Some(parttype) = &self.parttype { |
| 29 | + if parttype.to_lowercase() == ESP_TYPE_GUID { |
| 30 | + return true; |
| 31 | + } |
| 32 | + } |
| 33 | + false |
| 34 | + } |
| 35 | + |
| 36 | + pub(crate) fn is_bios_boot_part(&self) -> bool { |
| 37 | + const BIOS_BOOT_TYPE_GUID: &str = "21686148-6449-6e6f-744e-656564454649"; |
| 38 | + if let Some(parttype) = &self.parttype { |
| 39 | + if parttype.to_lowercase() == BIOS_BOOT_TYPE_GUID |
| 40 | + && self.pttype.as_deref() == Some("gpt") |
| 41 | + { |
| 42 | + return true; |
| 43 | + } |
| 44 | + } |
| 45 | + false |
| 46 | + } |
| 47 | +} |
| 48 | + |
| 49 | +/// Parse key-value pairs from lsblk --pairs. |
| 50 | +/// Newer versions of lsblk support JSON but the one in CentOS 7 doesn't. |
| 51 | +fn split_lsblk_line(line: &str) -> HashMap<String, String> { |
| 52 | + static REGEX: OnceLock<Regex> = OnceLock::new(); |
| 53 | + let regex = REGEX.get_or_init(|| Regex::new(r#"([A-Z-_]+)="([^"]+)""#).unwrap()); |
| 54 | + let mut fields: HashMap<String, String> = HashMap::new(); |
| 55 | + for cap in regex.captures_iter(line) { |
| 56 | + fields.insert(cap[1].to_string(), cap[2].to_string()); |
| 57 | + } |
| 58 | + fields |
| 59 | +} |
| 60 | + |
| 61 | +/// This is a bit fuzzy, but... this function will return every block device in the parent |
| 62 | +/// hierarchy of `device` capable of containing other partitions. So e.g. parent devices of type |
| 63 | +/// "part" doesn't match, but "disk" and "mpath" does. |
| 64 | +pub(crate) fn find_parent_devices(device: &str) -> Result<Vec<String>> { |
| 65 | + let mut cmd = Command::new("lsblk"); |
| 66 | + // Older lsblk, e.g. in CentOS 7.6, doesn't support PATH, but --paths option |
| 67 | + cmd.arg("--pairs") |
| 68 | + .arg("--paths") |
| 69 | + .arg("--inverse") |
| 70 | + .arg("--output") |
| 71 | + .arg("NAME,TYPE") |
| 72 | + .arg(device); |
| 73 | + let output = util::cmd_output(&mut cmd)?; |
| 74 | + let mut parents = Vec::new(); |
| 75 | + // skip first line, which is the device itself |
| 76 | + for line in output.lines().skip(1) { |
| 77 | + let dev = split_lsblk_line(line); |
| 78 | + let name = dev |
| 79 | + .get("NAME") |
| 80 | + .with_context(|| format!("device in hierarchy of {device} missing NAME"))?; |
| 81 | + let kind = dev |
| 82 | + .get("TYPE") |
| 83 | + .with_context(|| format!("device in hierarchy of {device} missing TYPE"))?; |
| 84 | + if kind == "disk" { |
| 85 | + parents.push(name.clone()); |
| 86 | + } else if kind == "mpath" { |
| 87 | + parents.push(name.clone()); |
| 88 | + // we don't need to know what disks back the multipath |
| 89 | + break; |
| 90 | + } |
| 91 | + } |
| 92 | + if parents.is_empty() { |
| 93 | + bail!("no parent devices found for {}", device); |
| 94 | + } |
| 95 | + Ok(parents) |
| 96 | +} |
| 97 | + |
| 98 | +#[context("get backing devices from mountpoint boot")] |
| 99 | +pub fn get_backing_devices<P: AsRef<Path>>(target_root: P) -> Result<Vec<String>> { |
| 100 | + let target_root = target_root.as_ref(); |
| 101 | + let bootdir = target_root.join("boot"); |
| 102 | + if !bootdir.exists() { |
| 103 | + bail!("{} does not exist", bootdir.display()); |
| 104 | + } |
| 105 | + let bootdir = openat::Dir::open(&bootdir)?; |
| 106 | + let fsinfo = crate::filesystem::inspect_filesystem(&bootdir, ".")?; |
| 107 | + // Find the real underlying backing device for the root. |
| 108 | + let backing_devices = find_parent_devices(&fsinfo.source) |
| 109 | + .with_context(|| format!("while looking for backing devices of {}", fsinfo.source))?; |
| 110 | + log::debug!("Find backing devices: {backing_devices:?}"); |
| 111 | + Ok(backing_devices) |
| 112 | +} |
| 113 | + |
| 114 | +#[context("Listing parttype for device {device}")] |
| 115 | +fn list_dev(device: &str) -> Result<BlockDevices> { |
| 116 | + let mut cmd = Command::new("lsblk"); |
| 117 | + cmd.args([ |
| 118 | + "--json", |
| 119 | + "--output", |
| 120 | + "PATH,PTTYPE,PARTTYPE,PARTTYPENAME", |
| 121 | + device, |
| 122 | + ]); |
| 123 | + let output = util::cmd_output(&mut cmd)?; |
| 124 | + // Parse the JSON string into the `BlockDevices` struct |
| 125 | + let Ok(devs) = serde_json::from_str::<BlockDevices>(&output) else { |
| 126 | + bail!("Could not deserialize JSON output from lsblk"); |
| 127 | + }; |
| 128 | + Ok(devs) |
| 129 | +} |
| 130 | + |
| 131 | +/// Find esp partition on the same device |
| 132 | +pub fn get_esp_partition(device: &str) -> Result<Option<String>> { |
| 133 | + let dev = list_dev(&device)?; |
| 134 | + // Find the ESP part on the disk |
| 135 | + for part in dev.blockdevices { |
| 136 | + if part.is_esp_part() { |
| 137 | + return Ok(Some(part.path)); |
| 138 | + } |
| 139 | + } |
| 140 | + log::debug!("Not found any esp partition"); |
| 141 | + Ok(None) |
| 142 | +} |
| 143 | + |
| 144 | +/// Find all ESP partitions on the backing devices with mountpoint boot |
| 145 | +pub fn find_colocated_esps<P: AsRef<Path>>(target_root: P) -> Result<Vec<String>> { |
| 146 | + // first, get the parent device |
| 147 | + let backing_devices = |
| 148 | + get_backing_devices(&target_root).with_context(|| "while looking for colocated ESPs")?; |
| 149 | + |
| 150 | + // now, look for all ESPs on those devices |
| 151 | + let mut esps = Vec::new(); |
| 152 | + for parent_device in backing_devices { |
| 153 | + if let Some(esp) = get_esp_partition(&parent_device)? { |
| 154 | + esps.push(esp) |
| 155 | + } |
| 156 | + } |
| 157 | + log::debug!("Find esp partitions: {esps:?}"); |
| 158 | + Ok(esps) |
| 159 | +} |
| 160 | + |
| 161 | +/// Find bios_boot partition on the same device |
| 162 | +pub fn get_bios_boot_partition(device: &str) -> Result<Option<String>> { |
| 163 | + let dev = list_dev(&device)?; |
| 164 | + // Find the BIOS BOOT part on the disk |
| 165 | + for part in dev.blockdevices { |
| 166 | + if part.is_bios_boot_part() { |
| 167 | + return Ok(Some(part.path)); |
| 168 | + } |
| 169 | + } |
| 170 | + log::debug!("Not found any bios_boot partition"); |
| 171 | + Ok(None) |
| 172 | +} |
| 173 | + |
| 174 | +/// Find all bios_boot partitions on the backing devices with mountpoint boot |
| 175 | +pub fn find_colocated_bios_boot<P: AsRef<Path>>(target_root: P) -> Result<Vec<String>> { |
| 176 | + // first, get the parent device |
| 177 | + let backing_devices = get_backing_devices(&target_root) |
| 178 | + .with_context(|| "looking for colocated bios_boot parts")?; |
| 179 | + |
| 180 | + // now, look for all bios_boot parts on those devices |
| 181 | + let mut bios_boots = Vec::new(); |
| 182 | + for parent_device in backing_devices { |
| 183 | + if let Some(bios) = get_bios_boot_partition(&parent_device)? { |
| 184 | + bios_boots.push(bios) |
| 185 | + } |
| 186 | + } |
| 187 | + log::debug!("Find bios_boot partitions: {bios_boots:?}"); |
| 188 | + Ok(bios_boots) |
| 189 | +} |
| 190 | + |
| 191 | +#[cfg(test)] |
| 192 | +mod tests { |
| 193 | + use super::*; |
| 194 | + |
| 195 | + #[test] |
| 196 | + fn test_deserialize_lsblk_output() { |
| 197 | + let data = include_str!("../tests/fixtures/example-lsblk-output.json"); |
| 198 | + let devices: BlockDevices = |
| 199 | + serde_json::from_str(&data).expect("JSON was not well-formatted"); |
| 200 | + assert_eq!(devices.blockdevices.len(), 7); |
| 201 | + assert_eq!(devices.blockdevices[0].path, "/dev/sr0"); |
| 202 | + assert!(devices.blockdevices[0].pttype.is_none()); |
| 203 | + assert!(devices.blockdevices[0].parttypename.is_none()); |
| 204 | + } |
| 205 | +} |
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