Support adding DHT bootstrap nodes to created torrents

The --dht-node flag can be used to add DHT bootstrap nodes to new torrents.

This is the only piece of metainfo-related functionality in BEP 5, so we can mark BEP
5 as implemented.

type: added

README.md

@@ -81,7 +81,7 @@ at any time.
 | [02](http://bittorrent.org/beps/bep_0002.html) | :heavy_minus_sign:                                    | Sample reStructured Text BEP Template                            |
 | [03](http://bittorrent.org/beps/bep_0003.html) | :white_check_mark:                                    | The BitTorrent Protocol Specification                            |
 | [04](http://bittorrent.org/beps/bep_0004.html) | :heavy_minus_sign:                                    | Assigned Numbers                                                 |
-| [05](http://bittorrent.org/beps/bep_0005.html) | [:x:](https://github.com/casey/intermodal/issues/90)  | DHT Protocol                                                     |
+| [05](http://bittorrent.org/beps/bep_0005.html) | :white_check_mark:                                    | DHT Protocol                                                     |
 | [06](http://bittorrent.org/beps/bep_0006.html) | :heavy_minus_sign:                                    | Fast Extension                                                   |
 | [07](http://bittorrent.org/beps/bep_0007.html) | :heavy_minus_sign:                                    | IPv6 Tracker Extension                                           |
 | [08](http://bittorrent.org/beps/bep_0008.html) | :heavy_minus_sign:                                    | Tracker Peer Obfuscation                                         |

src/common.rs

@@ -11,7 +11,7 @@ pub(crate) use std::{
   hash::Hash,
   io::{self, Read, Write},
   iter::{self, Sum},
-  num::{ParseFloatError, TryFromIntError},
+  num::{ParseFloatError, ParseIntError, TryFromIntError},
   ops::{AddAssign, Div, DivAssign, Mul, MulAssign, SubAssign},
   path::{self, Path, PathBuf},
   process::{self, Command, ExitStatus},
@@ -26,7 +26,7 @@ pub(crate) use chrono::{TimeZone, Utc};
 pub(crate) use globset::{Glob, GlobMatcher};
 pub(crate) use libc::EXIT_FAILURE;
 pub(crate) use regex::{Regex, RegexSet};
-pub(crate) use serde::{Deserialize, Serialize};
+pub(crate) use serde::{de::Error as _, Deserialize, Deserializer, Serialize, Serializer};
 pub(crate) use serde_hex::SerHex;
 pub(crate) use serde_with::rust::unwrap_or_skip;
 pub(crate) use sha1::Sha1;
@@ -37,7 +37,7 @@ pub(crate) use structopt::{
   StructOpt,
 };
 pub(crate) use unicode_width::UnicodeWidthStr;
-pub(crate) use url::Url;
+pub(crate) use url::{Host, Url};
 pub(crate) use walkdir::WalkDir;
 
 // modules
@@ -53,7 +53,7 @@ pub(crate) use crate::{
 pub(crate) use crate::{
   bytes::Bytes, env::Env, error::Error, file_info::FileInfo, file_path::FilePath,
   file_status::FileStatus, files::Files, hasher::Hasher, info::Info, lint::Lint, linter::Linter,
-  md5_digest::Md5Digest, metainfo::Metainfo, mode::Mode, opt::Opt,
+  md5_digest::Md5Digest, metainfo::Metainfo, mode::Mode, node::Node, opt::Opt,
   piece_length_picker::PieceLengthPicker, platform::Platform, status::Status, style::Style,
   table::Table, target::Target, torrent_summary::TorrentSummary, use_color::UseColor,
   verifier::Verifier, walker::Walker,

src/error.rs

@@ -29,14 +29,25 @@ pub(crate) enum Error {
   CommandInvoke { command: String, source: io::Error },
   #[snafu(display("Command `{}` returned bad exit status: {}", command, status))]
   CommandStatus { command: String, status: ExitStatus },
-  #[snafu(display("Filename was not valid unicode: {}", filename.to_string_lossy()))]
+  #[snafu(display("Filename was not valid unicode: {}", filename.display()))]
-  FilenameDecode { filename: OsString },
+  FilenameDecode { filename: PathBuf },
   #[snafu(display("Path had no file name: {}", path.display()))]
   FilenameExtract { path: PathBuf },
   #[snafu(display("I/O error at `{}`: {}", path.display(), source))]
   Filesystem { source: io::Error, path: PathBuf },
   #[snafu(display("Invalid glob: {}", source))]
   GlobParse { source: globset::Error },
+  #[snafu(display("Unknown lint: {}", text))]
+  LintUnknown { text: String },
+  #[snafu(display("DHT node port missing: {}", text))]
+  NodeParsePortMissing { text: String },
+  #[snafu(display("Failed to parse DHT node host `{}`: {}", text, source))]
+  NodeParseHost {
+    text: String,
+    source: url::ParseError,
+  },
+  #[snafu(display("Failed to parse DHT node port `{}`: {}", text, source))]
+  NodeParsePort { text: String, source: ParseIntError },
   #[snafu(display("Failed to find opener utility, please install one of {}", tried.join(",")))]
   OpenerMissing { tried: &'static [&'static str] },
   #[snafu(display(
@@ -104,8 +115,6 @@ pub(crate) enum Error {
     feature
   ))]
   Unstable { feature: &'static str },
-  #[snafu(display("Unknown lint: {}", text))]
-  LintUnknown { text: String },
   #[snafu(display("Torrent verification failed: {}", status))]
   Verify { status: Status },
 }

src/main.rs

@@ -72,6 +72,7 @@ mod linter;
 mod md5_digest;
 mod metainfo;
 mod mode;
+mod node;
 mod opt;
 mod path_ext;
 mod piece_length_picker;

src/metainfo.rs

@@ -3,8 +3,8 @@ use crate::common::*;
 #[derive(Deserialize, Serialize, Debug, PartialEq, Clone)]
 pub(crate) struct Metainfo {
   pub(crate) announce: String,
-  #[serde(rename = "announce-list")]
   #[serde(
+    rename = "announce-list",
     skip_serializing_if = "Option::is_none",
     default,
     with = "unwrap_or_skip"
@@ -16,15 +16,15 @@ pub(crate) struct Metainfo {
     with = "unwrap_or_skip"
   )]
   pub(crate) comment: Option<String>,
-  #[serde(rename = "created by")]
   #[serde(
+    rename = "created by",
     skip_serializing_if = "Option::is_none",
     default,
     with = "unwrap_or_skip"
   )]
   pub(crate) created_by: Option<String>,
-  #[serde(rename = "creation date")]
   #[serde(
+    rename = "creation date",
     skip_serializing_if = "Option::is_none",
     default,
     with = "unwrap_or_skip"
@@ -37,6 +37,12 @@ pub(crate) struct Metainfo {
   )]
   pub(crate) encoding: Option<String>,
   pub(crate) info: Info,
+  #[serde(
+    skip_serializing_if = "Option::is_none",
+    default,
+    with = "unwrap_or_skip"
+  )]
+  pub(crate) nodes: Option<Vec<Node>>,
 }
 
 impl Metainfo {
@@ -103,6 +109,7 @@ mod tests {
       created_by: Some("created by".into()),
       creation_date: Some(1),
       encoding: Some("UTF-8".into()),
+      nodes: Some(vec!["x:12".parse().unwrap(), "1.1.1.1:16".parse().unwrap()]),
       info: Info {
         private: Some(true),
         piece_length: Bytes(16 * 1024),
@@ -130,6 +137,7 @@ mod tests {
     let value = Metainfo {
       announce: "announce".into(),
       announce_list: Some(vec![vec!["announce".into(), "b".into()], vec!["c".into()]]),
+      nodes: Some(vec!["x:12".parse().unwrap(), "1.1.1.1:16".parse().unwrap()]),
       comment: Some("comment".into()),
       created_by: Some("created by".into()),
       creation_date: Some(1),

src/node.rs

@@ -0,0 +1,148 @@
+use crate::common::*;
+
+#[derive(Debug, PartialEq, Clone)]
+pub(crate) struct Node {
+  host: Host,
+  port: u16,
+}
+
+impl FromStr for Node {
+  type Err = Error;
+
+  fn from_str(text: &str) -> Result<Self, Self::Err> {
+    let socket_address_re = Regex::new(
+      r"(?x)
+      ^
+      (?P<host>.*?)
+      :
+      (?P<port>\d+?)
+      $
+      ",
+    )
+    .unwrap();
+
+    if let Some(captures) = socket_address_re.captures(text) {
+      let host_text = captures.name("host").unwrap().as_str();
+      let port_text = captures.name("port").unwrap().as_str();
+
+      let host = Host::parse(&host_text).context(error::NodeParseHost {
+        text: text.to_owned(),
+      })?;
+
+      let port = port_text.parse::<u16>().context(error::NodeParsePort {
+        text: text.to_owned(),
+      })?;
+
+      Ok(Self { host, port })
+    } else {
+      Err(Error::NodeParsePortMissing {
+        text: text.to_owned(),
+      })
+    }
+  }
+}
+
+impl Display for Node {
+  fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+    write!(f, "{}:{}", self.host, self.port)
+  }
+}
+
+#[derive(Serialize, Deserialize)]
+struct Tuple(String, u16);
+
+impl From<&Node> for Tuple {
+  fn from(node: &Node) -> Self {
+    let host = match &node.host {
+      Host::Domain(domain) => domain.to_string(),
+      Host::Ipv4(ipv4) => ipv4.to_string(),
+      Host::Ipv6(ipv6) => ipv6.to_string(),
+    };
+    Self(host, node.port)
+  }
+}
+
+impl Serialize for Node {
+  fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+  where
+    S: Serializer,
+  {
+    Tuple::from(self).serialize(serializer)
+  }
+}
+
+impl<'de> Deserialize<'de> for Node {
+  fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+  where
+    D: Deserializer<'de>,
+  {
+    let tuple = Tuple::deserialize(deserializer)?;
+
+    let host = if tuple.0.contains(':') {
+      Host::parse(&format!("[{}]", tuple.0))
+    } else {
+      Host::parse(&tuple.0)
+    }
+    .map_err(|error| D::Error::custom(format!("Failed to parse node host: {}", error)))?;
+
+    Ok(Node {
+      host,
+      port: tuple.1,
+    })
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  use std::net::{Ipv4Addr, Ipv6Addr};
+
+  fn case(host: Host, port: u16, text: &str, bencode: &str) {
+    let node = Node { host, port };
+    let parsed: Node = text.parse().expect(&format!("Failed to parse {}", text));
+    assert_eq!(parsed, node);
+    let ser = bendy::serde::to_bytes(&node).unwrap();
+    assert_eq!(
+      ser,
+      bencode.as_bytes(),
+      "Unexpected serialization: {} != {}",
+      String::from_utf8_lossy(&ser),
+      bencode,
+    );
+    let de = bendy::serde::from_bytes::<Node>(&ser).unwrap();
+    assert_eq!(de, node);
+  }
+
+  #[test]
+  fn test_domain() {
+    case(
+      Host::Domain("imdl.com".to_owned()),
+      12,
+      "imdl.com:12",
+      "l8:imdl.comi12ee",
+    );
+  }
+
+  #[test]
+  fn test_ipv4() {
+    case(
+      Host::Ipv4(Ipv4Addr::new(1, 2, 3, 4)),
+      100,
+      "1.2.3.4:100",
+      "l7:1.2.3.4i100ee",
+    );
+  }
+
+  #[test]
+  fn test_ipv6() {
+    case(
+      Host::Ipv6(Ipv6Addr::new(
+        0x1234, 0x5678, 0x9ABC, 0xDEF0, 0x1234, 0x5678, 0x9ABC, 0xDEF0,
+      )),
+      65000,
+      "[1234:5678:9abc:def0:1234:5678:9abc:def0]:65000",
+      "l39:1234:5678:9abc:def0:1234:5678:9abc:def0i65000ee",
+    );
+  }
+}

src/opt/torrent/create.rs

@@ -43,6 +43,16 @@ Note: Many BitTorrent clients do not implement the behavior described in BEP 12.
     long_help = "Include `COMMENT` in generated `.torrent` file. Stored under `comment` key of top-level metainfo dictionary."
   )]
   comment: Option<String>,
+  #[structopt(
+    name = "NODE",
+    long = "dht-node",
+    help = "Add DHT bootstrap node `NODE` to torrent. `NODE` should be in the form `HOST:PORT`.",
+    long_help = "Add DHT bootstrap node `NODE` to torrent. `NODE` should be in the form `HOST:PORT`, where `HOST` is a domain name, an IPv4 address, or an IPv6 address surrounded by brackets. May be given more than once to add multiple bootstrap nodes. Examples:
+    `--dht-node router.example.com:1337`
+    `--dht-node 203.0.113.0:2290`
+    `--dht-node [2001:db8:4275:7920:6269:7463:6f69:6e21]:8832`"
+  )]
+  dht_nodes: Vec<Node>,
   #[structopt(
     name = "FOLLOW-SYMLINKS",
     long = "follow-symlinks",
@@ -197,7 +207,7 @@ impl Create {
       None => filename
         .to_str()
         .ok_or_else(|| Error::FilenameDecode {
-          filename: filename.to_os_string(),
+          filename: PathBuf::from(filename),
         })?
         .to_owned(),
     };
@@ -255,6 +265,11 @@ impl Create {
       } else {
         Some(announce_list)
       },
+      nodes: if self.dht_nodes.is_empty() {
+        None
+      } else {
+        Some(self.dht_nodes)
+      },
       creation_date,
       created_by,
       info,
@@ -370,7 +385,7 @@ mod tests {
       }
     };
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.private, None);
   }
 
@@ -383,7 +398,7 @@ mod tests {
       }
     };
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.private, Some(true));
   }
 
@@ -407,7 +422,7 @@ mod tests {
       }
     };
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.announce, "http://bar/");
     assert!(metainfo.announce_list.is_none());
   }
@@ -426,7 +441,7 @@ mod tests {
       }
     };
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(
       metainfo.announce,
       "udp://tracker.opentrackr.org:1337/announce"
@@ -439,7 +454,7 @@ mod tests {
     let mut env = environment(&["--input", "foo", "--announce", "wss://tracker.btorrent.xyz"]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.announce, "wss://tracker.btorrent.xyz/");
     assert!(metainfo.announce_list.is_none());
   }
@@ -456,7 +471,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.announce, "http://bar/");
     assert_eq!(
       metainfo.announce_list,
@@ -478,7 +493,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.announce, "http://bar/");
     assert_eq!(
       metainfo.announce_list,
@@ -494,7 +509,7 @@ mod tests {
     let mut env = environment(&["--input", "foo", "--announce", "http://bar"]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.comment, None);
   }
 
@@ -510,7 +525,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.comment.unwrap(), "Hello, world!");
   }
 
@@ -519,7 +534,7 @@ mod tests {
     let mut env = environment(&["--input", "foo", "--announce", "http://bar"]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.piece_length, Bytes::from(16 * 2u32.pow(10)));
   }
 
@@ -535,7 +550,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.piece_length, Bytes(64 * 1024));
   }
 
@@ -551,7 +566,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.piece_length, Bytes(512 * 1024));
   }
 
@@ -567,7 +582,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.name, "foo");
   }
 
@@ -585,7 +600,7 @@ mod tests {
     fs::create_dir(&dir).unwrap();
     fs::write(dir.join("bar"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo/bar.torrent");
+    let metainfo = env.load_metainfo("foo/bar.torrent");
     assert_eq!(metainfo.info.name, "bar");
   }
 
@@ -601,7 +616,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    env.load_torrent("x.torrent");
+    env.load_metainfo("x.torrent");
   }
 
   #[test]
@@ -609,7 +624,7 @@ mod tests {
     let mut env = environment(&["--input", "foo", "--announce", "http://bar"]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.created_by.unwrap(), consts::CREATED_BY_DEFAULT);
   }
 
@@ -624,7 +639,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.created_by, None);
   }
 
@@ -633,7 +648,7 @@ mod tests {
     let mut env = environment(&["--input", "foo", "--announce", "http://bar"]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.encoding, Some("UTF-8".into()));
   }
 
@@ -646,7 +661,7 @@ mod tests {
       .unwrap()
       .as_secs();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert!(metainfo.creation_date.unwrap() < now + 10);
     assert!(metainfo.creation_date.unwrap() > now - 10);
   }
@@ -662,7 +677,7 @@ mod tests {
     ]);
     fs::write(env.resolve("foo"), "").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.creation_date, None);
   }
 
@@ -672,7 +687,7 @@ mod tests {
     let contents = "bar";
     fs::write(env.resolve("foo"), contents).unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.pieces, Sha1::from(contents).digest().bytes());
     assert_eq!(
       metainfo.info.mode,
@@ -698,7 +713,7 @@ mod tests {
     let contents = "bar";
     fs::write(env.resolve("foo"), contents).unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     let pieces = Sha1::from("b")
       .digest()
       .bytes()
@@ -724,7 +739,7 @@ mod tests {
     let contents = "";
     fs::write(env.resolve("foo"), contents).unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.pieces.len(), 0);
     assert_eq!(
       metainfo.info.mode,
@@ -741,7 +756,7 @@ mod tests {
     let dir = env.resolve("foo");
     fs::create_dir(&dir).unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.pieces.len(), 0);
     assert_eq!(metainfo.info.mode, Mode::Multiple { files: Vec::new() })
   }
@@ -755,7 +770,7 @@ mod tests {
     let contents = "bar";
     fs::write(file, contents).unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.pieces, Sha1::from(contents).digest().bytes());
     match metainfo.info.mode {
       Mode::Multiple { files } => {
@@ -781,7 +796,7 @@ mod tests {
     let contents = "bar";
     fs::write(file, contents).unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.pieces, Sha1::from(contents).digest().bytes());
     match metainfo.info.mode {
       Mode::Multiple { files } => {
@@ -807,7 +822,7 @@ mod tests {
     fs::write(dir.join("x"), "xyz").unwrap();
     fs::write(dir.join("h"), "hij").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(
       metainfo.info.pieces,
       Sha1::from("abchijxyz").digest().bytes()
@@ -924,7 +939,7 @@ mod tests {
     let dir = env.resolve("foo");
     fs::create_dir(&dir).unwrap();
     env.run().unwrap();
-    env.load_torrent("foo.torrent");
+    env.load_metainfo("foo.torrent");
   }
 
   #[test]
@@ -972,7 +987,7 @@ mod tests {
     let dir = env.resolve("foo");
     fs::create_dir(&dir).unwrap();
     env.run().unwrap();
-    env.load_torrent("foo.torrent");
+    env.load_metainfo("foo.torrent");
   }
 
   #[test]
@@ -1053,7 +1068,7 @@ Content Size  9 bytes
     fs::write(env.resolve("foo"), "").unwrap();
     fs::write(env.resolve("foo.torrent"), "foo").unwrap();
     env.run().unwrap();
-    env.load_torrent("foo.torrent");
+    env.load_metainfo("foo.torrent");
   }
 
   #[test]
@@ -1064,7 +1079,7 @@ Content Size  9 bytes
     fs::write(dir.join("Thumbs.db"), "abc").unwrap();
     fs::write(dir.join("Desktop.ini"), "abc").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.is_empty()
@@ -1086,7 +1101,7 @@ Content Size  9 bytes
     fs::write(dir.join("Thumbs.db"), "abc").unwrap();
     fs::write(dir.join("Desktop.ini"), "abc").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.len() == 2
@@ -1121,7 +1136,7 @@ Content Size  9 bytes
         .unwrap();
     }
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.len() == 0
@@ -1142,7 +1157,7 @@ Content Size  9 bytes
     fs::create_dir(&dir).unwrap();
     fs::write(dir.join(".hidden"), "abc").unwrap();
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.len() == 1
@@ -1185,7 +1200,7 @@ Content Size  9 bytes
     let mut env = environment(&["--input", "foo", "--announce", "http://bar", "--md5sum"]);
     populate_symlinks(&env);
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.is_empty()
@@ -1206,7 +1221,7 @@ Content Size  9 bytes
     ]);
     populate_symlinks(&env);
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_eq!(metainfo.info.pieces, Sha1::from("barbaz").digest().bytes());
     match metainfo.info.mode {
       Mode::Multiple { files } => {
@@ -1253,7 +1268,7 @@ Content Size  9 bytes
     env.create_dir("foo/.bar");
     env.create_file("foo/.bar/baz", "baz");
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.is_empty()
@@ -1286,7 +1301,7 @@ Content Size  9 bytes
         .unwrap();
     }
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.is_empty()
@@ -1302,7 +1317,7 @@ Content Size  9 bytes
     env.create_file("foo/b", "b");
     env.create_file("foo/c", "c");
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.len() == 2
@@ -1318,7 +1333,7 @@ Content Size  9 bytes
     env.create_file("foo/b", "b");
     env.create_file("foo/c", "c");
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.len() == 3
@@ -1341,7 +1356,7 @@ Content Size  9 bytes
     env.create_file("foo/b", "b");
     env.create_file("foo/c", "c");
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.len() == 2
@@ -1357,7 +1372,7 @@ Content Size  9 bytes
     env.create_file("foo/b", "b");
     env.create_file("foo/c", "c");
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.is_empty()
@@ -1384,11 +1399,68 @@ Content Size  9 bytes
     env.create_file("foo/b", "b");
     env.create_file("foo/c", "c");
     env.run().unwrap();
-    let metainfo = env.load_torrent("foo.torrent");
+    let metainfo = env.load_metainfo("foo.torrent");
     assert_matches!(
       metainfo.info.mode,
       Mode::Multiple { files } if files.len() == 1
     );
     assert_eq!(metainfo.info.pieces, Sha1::from("a").digest().bytes());
   }
+
+  #[test]
+  fn nodes_default() {
+    let mut env = env! {
+      args: ["--input", "foo", "--announce", "http://bar"],
+      tree: {
+        foo: "",
+      }
+    };
+    env.run().unwrap();
+    let metainfo = env.load_metainfo("foo.torrent");
+    assert!(metainfo.nodes.is_none());
+  }
+
+  #[test]
+  fn nodes_invalid() {
+    let mut env = env! {
+      args: ["--input", "foo", "--announce", "http://bar", "--dht-node", "blah"],
+      tree: {
+        foo: "",
+      },
+    };
+    assert_matches!(env.run(), Err(Error::Clap { .. }));
+  }
+
+  #[test]
+  fn nodes_valid() {
+    let mut env = env! {
+      args: [
+        "--input",
+        "foo",
+        "--announce",
+        "http://bar",
+        "--dht-node",
+        "router.example.com:1337",
+        "--dht-node",
+        "203.0.113.0:2290",
+        "--dht-node",
+        "[2001:db8:4275:7920:6269:7463:6f69:6e21]:8832",
+      ],
+      tree: {
+        foo: "",
+      },
+    };
+    env.run().unwrap();
+    let metainfo = env.load_metainfo("foo.torrent");
+    assert_eq!(
+      metainfo.nodes,
+      Some(vec![
+        "router.example.com:1337".parse().unwrap(),
+        "203.0.113.0:2290".parse().unwrap(),
+        "[2001:db8:4275:7920:6269:7463:6f69:6e21]:8832"
+          .parse()
+          .unwrap(),
+      ]),
+    );
+  }
 }

src/opt/torrent/show.rs

@@ -36,6 +36,11 @@ mod tests {
     let metainfo = Metainfo {
       announce: "announce".into(),
       announce_list: Some(vec![vec!["announce".into(), "b".into()], vec!["c".into()]]),
+      nodes: Some(vec![
+        "x:12".parse().unwrap(),
+        "1.1.1.1:16".parse().unwrap(),
+        "[2001:0db8:85a3::0000:8a2e:0370]:7334".parse().unwrap(),
+      ]),
       comment: Some("comment".into()),
       created_by: Some("created by".into()),
       creation_date: Some(1),
@@ -74,12 +79,15 @@ mod tests {
   Created By  created by
       Source  source
    Info Hash  b7595205a46491b3e8686e10b28efe7144d066cc
-Torrent Size  252 bytes
+Torrent Size  319 bytes
 Content Size  20 bytes
      Private  yes
     Trackers  Tier 1: announce
                       b
               Tier 2: c
+   DHT Nodes  x:12
+              1.1.1.1:16
+              [2001:db8:85a3::8a2e:370]:7334
   Piece Size  16 KiB
  Piece Count  1
   File Count  1
@@ -108,10 +116,11 @@ Created\t1970-01-01 00:00:01 UTC
 Created By\tcreated by
 Source\tsource
 Info Hash\tb7595205a46491b3e8686e10b28efe7144d066cc
-Torrent Size\t252
+Torrent Size\t319
 Content Size\t20
 Private\tyes
 Trackers\tannounce\tb\tc
+DHT Nodes\tx:12\t1.1.1.1:16\t[2001:db8:85a3::8a2e:370]:7334
 Piece Size\t16384
 Piece Count\t1
 File Count\t1
@@ -129,6 +138,11 @@ Files\tfoo
       announce_list: Some(vec![vec!["x".into()], vec!["y".into()], vec!["z".into()]]),
       comment: Some("comment".into()),
       created_by: Some("created by".into()),
+      nodes: Some(vec![
+        "x:12".parse().unwrap(),
+        "1.1.1.1:16".parse().unwrap(),
+        "[2001:0db8:85a3::0000:8a2e:0370]:7334".parse().unwrap(),
+      ]),
       creation_date: Some(1),
       encoding: Some("UTF-8".into()),
       info: Info {
@@ -165,13 +179,16 @@ Files\tfoo
   Created By  created by
       Source  source
    Info Hash  b7595205a46491b3e8686e10b28efe7144d066cc
-Torrent Size  240 bytes
+Torrent Size  307 bytes
 Content Size  20 bytes
      Private  yes
     Trackers  a
               x
               y
               z
+   DHT Nodes  x:12
+              1.1.1.1:16
+              [2001:db8:85a3::8a2e:370]:7334
   Piece Size  16 KiB
  Piece Count  1
   File Count  1
@@ -200,10 +217,11 @@ Created\t1970-01-01 00:00:01 UTC
 Created By\tcreated by
 Source\tsource
 Info Hash\tb7595205a46491b3e8686e10b28efe7144d066cc
-Torrent Size\t240
+Torrent Size\t307
 Content Size\t20
 Private\tyes
 Trackers\ta\tx\ty\tz
+DHT Nodes\tx:12\t1.1.1.1:16\t[2001:db8:85a3::8a2e:370]:7334
 Piece Size\t16384
 Piece Count\t1
 File Count\t1
@@ -220,6 +238,11 @@ Files\tfoo
       announce: "a".into(),
       announce_list: Some(vec![vec!["b".into()], vec!["c".into()], vec!["a".into()]]),
       comment: Some("comment".into()),
+      nodes: Some(vec![
+        "x:12".parse().unwrap(),
+        "1.1.1.1:16".parse().unwrap(),
+        "[2001:0db8:85a3::8a2e:0370]:7334".parse().unwrap(),
+      ]),
       created_by: Some("created by".into()),
       creation_date: Some(1),
       encoding: Some("UTF-8".into()),
@@ -257,12 +280,15 @@ Files\tfoo
   Created By  created by
       Source  source
    Info Hash  b7595205a46491b3e8686e10b28efe7144d066cc
-Torrent Size  240 bytes
+Torrent Size  307 bytes
 Content Size  20 bytes
      Private  yes
     Trackers  b
               c
               a
+   DHT Nodes  x:12
+              1.1.1.1:16
+              [2001:db8:85a3::8a2e:370]:7334
   Piece Size  16 KiB
  Piece Count  1
   File Count  1
@@ -291,10 +317,11 @@ Created\t1970-01-01 00:00:01 UTC
 Created By\tcreated by
 Source\tsource
 Info Hash\tb7595205a46491b3e8686e10b28efe7144d066cc
-Torrent Size\t240
+Torrent Size\t307
 Content Size\t20
 Private\tyes
 Trackers\tb\tc\ta
+DHT Nodes\tx:12\t1.1.1.1:16\t[2001:db8:85a3::8a2e:370]:7334
 Piece Size\t16384
 Piece Count\t1
 File Count\t1

src/test_env.rs

@@ -31,7 +31,7 @@ impl TestEnv {
     fs::write(self.env.resolve(path), bytes.as_ref()).unwrap();
   }
 
-  pub(crate) fn load_torrent(&self, filename: impl AsRef<Path>) -> Metainfo {
+  pub(crate) fn load_metainfo(&self, filename: impl AsRef<Path>) -> Metainfo {
     Metainfo::load(self.env.resolve(filename.as_ref())).unwrap()
   }
 }

src/torrent_summary.rs

@@ -142,6 +142,16 @@ impl TorrentSummary {
       None => table.row("Tracker", &self.metainfo.announce),
     }
 
+    if let Some(nodes) = &self.metainfo.nodes {
+      table.list(
+        "DHT Nodes",
+        nodes
+          .iter()
+          .map(ToString::to_string)
+          .collect::<Vec<String>>(),
+      );
+    }
+
     table.size("Piece Size", self.metainfo.info.piece_length);
 
     table.row("Piece Count", self.metainfo.info.pieces.len() / 20);