src/bin/proxmox_backup_client/key.rs

   1 use std::path::PathBuf;
   2 use std::io::Write;
   3 use std::process::{Stdio, Command};
   4
   5 use anyhow::{bail, format_err, Error};
   6 use serde::{Deserialize, Serialize};
   7 use serde_json::Value;
   8
   9 use proxmox::api::api;
  10 use proxmox::api::cli::{
  11     ColumnConfig,
  12     CliCommand,
  13     CliCommandMap,
  14     format_and_print_result_full,
  15     get_output_format,
  16     OUTPUT_FORMAT,
  17 };
  18 use proxmox::api::router::ReturnType;
  19 use proxmox::sys::linux::tty;
  20 use proxmox::tools::fs::{file_get_contents, replace_file, CreateOptions};
  21
  22 use proxmox_backup::{
  23     api2::types::{
  24         PASSWORD_HINT_SCHEMA,
  25         KeyInfo,
  26         Kdf,
  27     },
  28     backup::{
  29         rsa_decrypt_key_config,
  30         CryptConfig,
  31         KeyConfig,
  32     },
  33     tools,
  34 };
  35
  36 #[api()]
  37 #[derive(Debug, Serialize, Deserialize)]
  38 #[serde(rename_all = "lowercase")]
  39 /// Paperkey output format
  40 pub enum PaperkeyFormat {
  41     /// Format as Utf8 text. Includes QR codes as ascii-art.
  42     Text,
  43     /// Format as Html. Includes QR codes as png images.
  44     Html,
  45 }
  46
  47 pub const DEFAULT_ENCRYPTION_KEY_FILE_NAME: &str = "encryption-key.json";
  48 pub const MASTER_PUBKEY_FILE_NAME: &str = "master-public.pem";
  49
  50 pub fn find_master_pubkey() -> Result<Option<PathBuf>, Error> {
  51     super::find_xdg_file(MASTER_PUBKEY_FILE_NAME, "main public key file")
  52 }
  53
  54 pub fn place_master_pubkey() -> Result<PathBuf, Error> {
  55     super::place_xdg_file(MASTER_PUBKEY_FILE_NAME, "main public key file")
  56 }
  57
  58 pub fn find_default_encryption_key() -> Result<Option<PathBuf>, Error> {
  59     super::find_xdg_file(DEFAULT_ENCRYPTION_KEY_FILE_NAME, "default encryption key file")
  60 }
  61
  62 pub fn place_default_encryption_key() -> Result<PathBuf, Error> {
  63     super::place_xdg_file(DEFAULT_ENCRYPTION_KEY_FILE_NAME, "default encryption key file")
  64 }
  65
  66 pub fn read_optional_default_encryption_key() -> Result<Option<Vec<u8>>, Error> {
  67     find_default_encryption_key()?
  68         .map(file_get_contents)
  69         .transpose()
  70 }
  71
  72 pub fn get_encryption_key_password() -> Result<Vec<u8>, Error> {
  73     // fixme: implement other input methods
  74
  75     use std::env::VarError::*;
  76     match std::env::var("PBS_ENCRYPTION_PASSWORD") {
  77         Ok(p) => return Ok(p.as_bytes().to_vec()),
  78         Err(NotUnicode(_)) => bail!("PBS_ENCRYPTION_PASSWORD contains bad characters"),
  79         Err(NotPresent) => {
  80             // Try another method
  81         }
  82     }
  83
  84     // If we're on a TTY, query the user for a password
  85     if tty::stdin_isatty() {
  86         return Ok(tty::read_password("Encryption Key Password: ")?);
  87     }
  88
  89     bail!("no password input mechanism available");
  90 }
  91
  92 #[api(
  93     input: {
  94         properties: {
  95             kdf: {
  96                 type: Kdf,
  97                 optional: true,
  98             },
  99             path: {
 100                 description:
 101                     "Output file. Without this the key will become the new default encryption key.",
 102                 optional: true,
 103             },
 104             hint: {
 105                 schema: PASSWORD_HINT_SCHEMA,
 106                 optional: true,
 107             },
 108         },
 109     },
 110 )]
 111 /// Create a new encryption key.
 112 fn create(
 113     kdf: Option<Kdf>,
 114     path: Option<String>,
 115     hint: Option<String>
 116 ) -> Result<(), Error> {
 117     let path = match path {
 118         Some(path) => PathBuf::from(path),
 119         None => {
 120             let path = place_default_encryption_key()?;
 121             println!("creating default key at: {:?}", path);
 122             path
 123         }
 124     };
 125
 126     let kdf = kdf.unwrap_or_default();
 127
 128     let mut key = [0u8; 32];
 129     proxmox::sys::linux::fill_with_random_data(&mut key)?;
 130     let crypt_config = CryptConfig::new(key.clone())?;
 131
 132     match kdf {
 133         Kdf::None => {
 134             if hint.is_some() {
 135                 bail!("password hint not allowed for Kdf::None");
 136             }
 137
 138             let mut key_config = KeyConfig::without_password(key);
 139             key_config.fingerprint = Some(crypt_config.fingerprint());
 140
 141             key_config.store(path, false)?;
 142         }
 143         Kdf::Scrypt | Kdf::PBKDF2 => {
 144             // always read passphrase from tty
 145             if !tty::stdin_isatty() {
 146                 bail!("unable to read passphrase - no tty");
 147             }
 148
 149             let password = tty::read_and_verify_password("Encryption Key Password: ")?;
 150
 151             let mut key_config = KeyConfig::with_key(&key, &password, kdf)?;
 152             key_config.fingerprint = Some(crypt_config.fingerprint());
 153             key_config.hint = hint;
 154
 155             key_config.store(&path, false)?;
 156         }
 157     }
 158
 159     Ok(())
 160 }
 161
 162 #[api(
 163     input: {
 164         properties: {
 165             "master-keyfile": {
 166                 description: "(Private) master key to use.",
 167             },
 168             "encrypted-keyfile": {
 169                 description: "RSA-encrypted keyfile to import.",
 170             },
 171             kdf: {
 172                 type: Kdf,
 173                 optional: true,
 174             },
 175             "path": {
 176                 description:
 177                     "Output file. Without this the key will become the new default encryption key.",
 178                 optional: true,
 179             },
 180             hint: {
 181                 schema: PASSWORD_HINT_SCHEMA,
 182                 optional: true,
 183             },
 184         },
 185     },
 186 )]
 187 /// Import an encrypted backup of an encryption key using a (private) master key.
 188 async fn import_with_master_key(
 189     master_keyfile: String,
 190     encrypted_keyfile: String,
 191     kdf: Option<Kdf>,
 192     path: Option<String>,
 193     hint: Option<String>,
 194 ) -> Result<(), Error> {
 195     let path = match path {
 196         Some(path) => PathBuf::from(path),
 197         None => {
 198             let path = place_default_encryption_key()?;
 199             if path.exists() {
 200                 bail!("Please remove default encryption key at {:?} before importing to default location (or choose a non-default one).", path);
 201             }
 202             println!("Importing key to default location at: {:?}", path);
 203             path
 204         }
 205     };
 206
 207     let encrypted_key = file_get_contents(&encrypted_keyfile)?;
 208     let master_key = file_get_contents(&master_keyfile)?;
 209     let password = tty::read_password("Master Key Password: ")?;
 210
 211     let master_key =
 212         openssl::pkey::PKey::private_key_from_pem_passphrase(&master_key, &password)
 213         .map_err(|err| format_err!("failed to read PEM-formatted private key - {}", err))?
 214         .rsa()
 215         .map_err(|err| format_err!("not a valid private RSA key - {}", err))?;
 216
 217     let (key, created, fingerprint) =
 218         rsa_decrypt_key_config(master_key, &encrypted_key, &get_encryption_key_password)?;
 219
 220     let kdf = kdf.unwrap_or_default();
 221     match kdf {
 222         Kdf::None => {
 223             if hint.is_some() {
 224                 bail!("password hint not allowed for Kdf::None");
 225             }
 226
 227             let mut key_config = KeyConfig::without_password(key);
 228             key_config.created = created; // keep original value
 229             key_config.fingerprint = Some(fingerprint);
 230
 231             key_config.store(path, true)?;
 232
 233         }
 234         Kdf::Scrypt | Kdf::PBKDF2 => {
 235             let password = tty::read_and_verify_password("New Password: ")?;
 236
 237             let mut new_key_config = KeyConfig::with_key(&key, &password, kdf)?;
 238             new_key_config.created = created; // keep original value
 239             new_key_config.fingerprint = Some(fingerprint);
 240             new_key_config.hint = hint;
 241
 242             new_key_config.store(path, true)?;
 243         }
 244     }
 245
 246     Ok(())
 247 }
 248
 249 #[api(
 250     input: {
 251         properties: {
 252             kdf: {
 253                 type: Kdf,
 254                 optional: true,
 255             },
 256             path: {
 257                 description: "Key file. Without this the default key's password will be changed.",
 258                 optional: true,
 259             },
 260             hint: {
 261                 schema: PASSWORD_HINT_SCHEMA,
 262                 optional: true,
 263             },
 264         },
 265     },
 266 )]
 267 /// Change the encryption key's password.
 268 fn change_passphrase(
 269     kdf: Option<Kdf>,
 270     path: Option<String>,
 271     hint: Option<String>,
 272 ) -> Result<(), Error> {
 273     let path = match path {
 274         Some(path) => PathBuf::from(path),
 275         None => {
 276             let path = find_default_encryption_key()?
 277                 .ok_or_else(|| {
 278                     format_err!("no encryption file provided and no default file found")
 279                 })?;
 280             println!("updating default key at: {:?}", path);
 281             path
 282         }
 283     };
 284
 285     let kdf = kdf.unwrap_or_default();
 286
 287     if !tty::stdin_isatty() {
 288         bail!("unable to change passphrase - no tty");
 289     }
 290
 291     let key_config = KeyConfig::load(&path)?;
 292     let (key, created, fingerprint) = key_config.decrypt(&get_encryption_key_password)?;
 293
 294     match kdf {
 295         Kdf::None => {
 296             if hint.is_some() {
 297                 bail!("password hint not allowed for Kdf::None");
 298             }
 299
 300             let mut key_config = KeyConfig::without_password(key);
 301             key_config.created =  created; // keep original value
 302             key_config.fingerprint = Some(fingerprint);
 303
 304             key_config.store(&path, true)?;
 305         }
 306         Kdf::Scrypt | Kdf::PBKDF2 => {
 307             let password = tty::read_and_verify_password("New Password: ")?;
 308
 309             let mut new_key_config = KeyConfig::with_key(&key, &password, kdf)?;
 310             new_key_config.created = created; // keep original value
 311             new_key_config.fingerprint = Some(fingerprint);
 312             new_key_config.hint = hint;
 313
 314             new_key_config.store(&path, true)?;
 315         }
 316     }
 317
 318     Ok(())
 319 }
 320
 321 #[api(
 322     input: {
 323         properties: {
 324             path: {
 325                 description: "Key file. Without this the default key's metadata will be shown.",
 326                 optional: true,
 327             },
 328             "output-format": {
 329                 schema: OUTPUT_FORMAT,
 330                 optional: true,
 331             },
 332         },
 333     },
 334 )]
 335 /// Print the encryption key's metadata.
 336 fn show_key(
 337     path: Option<String>,
 338     param: Value,
 339 ) -> Result<(), Error> {
 340     let path = match path {
 341         Some(path) => PathBuf::from(path),
 342         None => {
 343             let path = find_default_encryption_key()?
 344                 .ok_or_else(|| {
 345                     format_err!("no encryption file provided and no default file found")
 346                 })?;
 347             path
 348         }
 349     };
 350
 351
 352     let config: KeyConfig = serde_json::from_slice(&file_get_contents(path.clone())?)?;
 353
 354     let output_format = get_output_format(&param);
 355
 356     let mut info: KeyInfo = (&config).into();
 357     info.path = Some(format!("{:?}", path));
 358
 359     let options = proxmox::api::cli::default_table_format_options()
 360         .column(ColumnConfig::new("path"))
 361         .column(ColumnConfig::new("kdf"))
 362         .column(ColumnConfig::new("created").renderer(tools::format::render_epoch))
 363         .column(ColumnConfig::new("modified").renderer(tools::format::render_epoch))
 364         .column(ColumnConfig::new("fingerprint"))
 365         .column(ColumnConfig::new("hint"));
 366
 367     let return_type = ReturnType::new(false, &KeyInfo::API_SCHEMA);
 368
 369     format_and_print_result_full(
 370         &mut serde_json::to_value(info)?,
 371         &return_type,
 372         &output_format,
 373         &options,
 374     );
 375
 376     Ok(())
 377 }
 378
 379 #[api(
 380     input: {
 381         properties: {
 382             path: {
 383                 description: "Path to the PEM formatted RSA public key.",
 384             },
 385         },
 386     },
 387 )]
 388 /// Import an RSA public key used to put an encrypted version of the symmetric backup encryption
 389 /// key onto the backup server along with each backup.
 390 fn import_master_pubkey(path: String) -> Result<(), Error> {
 391     let pem_data = file_get_contents(&path)?;
 392
 393     if let Err(err) = openssl::pkey::PKey::public_key_from_pem(&pem_data) {
 394         bail!("Unable to decode PEM data - {}", err);
 395     }
 396
 397     let target_path = place_master_pubkey()?;
 398
 399     replace_file(&target_path, &pem_data, CreateOptions::new())?;
 400
 401     println!("Imported public master key to {:?}", target_path);
 402
 403     Ok(())
 404 }
 405
 406 #[api]
 407 /// Create an RSA public/private key pair used to put an encrypted version of the symmetric backup
 408 /// encryption key onto the backup server along with each backup.
 409 fn create_master_key() -> Result<(), Error> {
 410     // we need a TTY to query the new password
 411     if !tty::stdin_isatty() {
 412         bail!("unable to create master key - no tty");
 413     }
 414
 415     let rsa = openssl::rsa::Rsa::generate(4096)?;
 416     let pkey = openssl::pkey::PKey::from_rsa(rsa)?;
 417
 418     let password = String::from_utf8(tty::read_and_verify_password("Master Key Password: ")?)?;
 419
 420     let pub_key: Vec<u8> = pkey.public_key_to_pem()?;
 421     let filename_pub = "master-public.pem";
 422     println!("Writing public master key to {}", filename_pub);
 423     replace_file(filename_pub, pub_key.as_slice(), CreateOptions::new())?;
 424
 425     let cipher = openssl::symm::Cipher::aes_256_cbc();
 426     let priv_key: Vec<u8> = pkey.private_key_to_pem_pkcs8_passphrase(cipher, password.as_bytes())?;
 427
 428     let filename_priv = "master-private.pem";
 429     println!("Writing private master key to {}", filename_priv);
 430     replace_file(filename_priv, priv_key.as_slice(), CreateOptions::new())?;
 431
 432     Ok(())
 433 }
 434
 435 #[api(
 436     input: {
 437         properties: {
 438             path: {
 439                 description: "Key file. Without this the default key's will be used.",
 440                 optional: true,
 441             },
 442             subject: {
 443                 description: "Include the specified subject as titel text.",
 444                 optional: true,
 445             },
 446             "output-format": {
 447                 type: PaperkeyFormat,
 448                 optional: true,
 449             },
 450         },
 451     },
 452 )]
 453 /// Generate a printable, human readable text file containing the encryption key.
 454 ///
 455 /// This also includes a scanable QR code for fast key restore.
 456 fn paper_key(
 457     path: Option<String>,
 458     subject: Option<String>,
 459     output_format: Option<PaperkeyFormat>,
 460 ) -> Result<(), Error> {
 461     let path = match path {
 462         Some(path) => PathBuf::from(path),
 463         None => {
 464             let path = find_default_encryption_key()?
 465                 .ok_or_else(|| {
 466                     format_err!("no encryption file provided and no default file found")
 467                 })?;
 468             path
 469         }
 470     };
 471
 472     let data = file_get_contents(&path)?;
 473     let data = String::from_utf8(data)?;
 474
 475     let (data, is_private_key) = if data.starts_with("-----BEGIN ENCRYPTED PRIVATE KEY-----\n") {
 476         let lines: Vec<String> = data
 477             .lines()
 478             .map(|s| s.trim_end())
 479             .filter(|s| !s.is_empty())
 480             .map(String::from)
 481             .collect();
 482
 483         if !lines[lines.len()-1].starts_with("-----END ENCRYPTED PRIVATE KEY-----") {
 484             bail!("unexpected key format");
 485         }
 486
 487         if lines.len() < 20 {
 488             bail!("unexpected key format");
 489         }
 490
 491         (lines, true)
 492     } else {
 493         match serde_json::from_str::<KeyConfig>(&data) {
 494             Ok(key_config) => {
 495                 let lines = serde_json::to_string_pretty(&key_config)?
 496                     .lines()
 497                     .map(String::from)
 498                     .collect();
 499
 500                 (lines, false)
 501             },
 502             Err(err) => {
 503                 eprintln!("Couldn't parse '{:?}' as KeyConfig - {}", path, err);
 504                 bail!("Neither a PEM-formatted private key, nor a PBS key file.");
 505             },
 506         }
 507     };
 508
 509     let format = output_format.unwrap_or(PaperkeyFormat::Html);
 510
 511     match format {
 512         PaperkeyFormat::Html => paperkey_html(&data, subject, is_private_key),
 513         PaperkeyFormat::Text => paperkey_text(&data, subject, is_private_key),
 514     }
 515 }
 516
 517 pub fn cli() -> CliCommandMap {
 518     let key_create_cmd_def = CliCommand::new(&API_METHOD_CREATE)
 519         .arg_param(&["path"])
 520         .completion_cb("path", tools::complete_file_name);
 521
 522     let key_import_with_master_key_cmd_def = CliCommand::new(&API_METHOD_IMPORT_WITH_MASTER_KEY)
 523         .arg_param(&["master-keyfile"])
 524         .completion_cb("master-keyfile", tools::complete_file_name)
 525         .arg_param(&["encrypted-keyfile"])
 526         .completion_cb("encrypted-keyfile", tools::complete_file_name)
 527         .arg_param(&["path"])
 528         .completion_cb("path", tools::complete_file_name);
 529
 530     let key_change_passphrase_cmd_def = CliCommand::new(&API_METHOD_CHANGE_PASSPHRASE)
 531         .arg_param(&["path"])
 532         .completion_cb("path", tools::complete_file_name);
 533
 534     let key_create_master_key_cmd_def = CliCommand::new(&API_METHOD_CREATE_MASTER_KEY);
 535     let key_import_master_pubkey_cmd_def = CliCommand::new(&API_METHOD_IMPORT_MASTER_PUBKEY)
 536         .arg_param(&["path"])
 537         .completion_cb("path", tools::complete_file_name);
 538
 539     let key_show_cmd_def = CliCommand::new(&API_METHOD_SHOW_KEY)
 540         .arg_param(&["path"])
 541         .completion_cb("path", tools::complete_file_name);
 542
 543     let paper_key_cmd_def = CliCommand::new(&API_METHOD_PAPER_KEY)
 544         .arg_param(&["path"])
 545         .completion_cb("path", tools::complete_file_name);
 546
 547     CliCommandMap::new()
 548         .insert("create", key_create_cmd_def)
 549         .insert("import-with-master-key", key_import_with_master_key_cmd_def)
 550         .insert("create-master-key", key_create_master_key_cmd_def)
 551         .insert("import-master-pubkey", key_import_master_pubkey_cmd_def)
 552         .insert("change-passphrase", key_change_passphrase_cmd_def)
 553         .insert("show", key_show_cmd_def)
 554         .insert("paperkey", paper_key_cmd_def)
 555 }
 556
 557 fn paperkey_html(lines: &[String], subject: Option<String>, is_private: bool) -> Result<(), Error> {
 558
 559     let img_size_pt = 500;
 560
 561     println!("<!DOCTYPE html>");
 562     println!("<html lang=\"en\">");
 563     println!("<head>");
 564     println!("<meta charset=\"utf-8\">");
 565     println!("<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">");
 566     println!("<title>Proxmox Backup Paperkey</title>");
 567     println!("<style type=\"text/css\">");
 568
 569     println!("  p {{");
 570     println!("    font-size: 12pt;");
 571     println!("    font-family: monospace;");
 572     println!("    white-space: pre-wrap;");
 573     println!("    line-break: anywhere;");
 574     println!("  }}");
 575
 576     println!("</style>");
 577
 578     println!("</head>");
 579
 580     println!("<body>");
 581
 582     if let Some(subject) = subject {
 583         println!("<p>Subject: {}</p>", subject);
 584     }
 585
 586     if is_private {
 587         const BLOCK_SIZE: usize = 20;
 588         let blocks = (lines.len() + BLOCK_SIZE -1)/BLOCK_SIZE;
 589
 590         for i in 0..blocks {
 591             let start = i*BLOCK_SIZE;
 592             let mut end = start + BLOCK_SIZE;
 593             if end > lines.len() {
 594                 end = lines.len();
 595             }
 596             let data = &lines[start..end];
 597
 598             println!("<div style=\"page-break-inside: avoid;page-break-after: always\">");
 599             println!("<p>");
 600
 601             for l in start..end {
 602                 println!("{:02}: {}", l, lines[l]);
 603             }
 604
 605             println!("</p>");
 606
 607             let qr_code = generate_qr_code("svg", data)?;
 608             let qr_code = base64::encode_config(&qr_code, base64::STANDARD_NO_PAD);
 609
 610             println!("<center>");
 611             println!("<img");
 612             println!("width=\"{}pt\" height=\"{}pt\"", img_size_pt, img_size_pt);
 613             println!("src=\"data:image/svg+xml;base64,{}\"/>", qr_code);
 614             println!("</center>");
 615             println!("</div>");
 616        }
 617
 618         println!("</body>");
 619         println!("</html>");
 620         return Ok(());
 621     }
 622
 623     println!("<div style=\"page-break-inside: avoid\">");
 624
 625     println!("<p>");
 626
 627     println!("-----BEGIN PROXMOX BACKUP KEY-----");
 628
 629     for line in lines {
 630         println!("{}", line);
 631     }
 632
 633     println!("-----END PROXMOX BACKUP KEY-----");
 634
 635     println!("</p>");
 636
 637     let qr_code = generate_qr_code("svg", lines)?;
 638     let qr_code = base64::encode_config(&qr_code, base64::STANDARD_NO_PAD);
 639
 640     println!("<center>");
 641     println!("<img");
 642     println!("width=\"{}pt\" height=\"{}pt\"", img_size_pt, img_size_pt);
 643     println!("src=\"data:image/svg+xml;base64,{}\"/>", qr_code);
 644     println!("</center>");
 645
 646     println!("</div>");
 647
 648     println!("</body>");
 649     println!("</html>");
 650
 651     Ok(())
 652 }
 653
 654 fn paperkey_text(lines: &[String], subject: Option<String>, is_private: bool) -> Result<(), Error> {
 655
 656     if let Some(subject) = subject {
 657         println!("Subject: {}\n", subject);
 658     }
 659
 660     if is_private {
 661         const BLOCK_SIZE: usize = 5;
 662         let blocks = (lines.len() + BLOCK_SIZE -1)/BLOCK_SIZE;
 663
 664         for i in 0..blocks {
 665             let start = i*BLOCK_SIZE;
 666             let mut end = start + BLOCK_SIZE;
 667             if end > lines.len() {
 668                 end = lines.len();
 669             }
 670             let data = &lines[start..end];
 671
 672             for l in start..end {
 673                 println!("{:-2}: {}", l, lines[l]);
 674             }
 675             let qr_code = generate_qr_code("utf8i", data)?;
 676             let qr_code = String::from_utf8(qr_code)
 677                 .map_err(|_| format_err!("Failed to read qr code (got non-utf8 data)"))?;
 678             println!("{}", qr_code);
 679             println!("{}", char::from(12u8)); // page break
 680
 681         }
 682         return Ok(());
 683     }
 684
 685     println!("-----BEGIN PROXMOX BACKUP KEY-----");
 686     for line in lines {
 687         println!("{}", line);
 688     }
 689     println!("-----END PROXMOX BACKUP KEY-----");
 690
 691     let qr_code = generate_qr_code("utf8i", &lines)?;
 692     let qr_code = String::from_utf8(qr_code)
 693         .map_err(|_| format_err!("Failed to read qr code (got non-utf8 data)"))?;
 694
 695     println!("{}", qr_code);
 696
 697     Ok(())
 698 }
 699
 700 fn generate_qr_code(output_type: &str, lines: &[String]) -> Result<Vec<u8>, Error> {
 701     let mut child = Command::new("qrencode")
 702         .args(&["-t", output_type, "-m0", "-s1", "-lm", "--output", "-"])
 703         .stdin(Stdio::piped())
 704         .stdout(Stdio::piped())
 705         .spawn()?;
 706
 707     {
 708         let stdin = child.stdin.as_mut()
 709             .ok_or_else(|| format_err!("Failed to open stdin"))?;
 710         let data = lines.join("\n");
 711         stdin.write_all(data.as_bytes())
 712             .map_err(|_| format_err!("Failed to write to stdin"))?;
 713     }
 714
 715     let output = child.wait_with_output()
 716         .map_err(|_| format_err!("Failed to read stdout"))?;
 717
 718     let output = crate::tools::command_output(output, None)?;
 719
 720     Ok(output)
 721 }