aria2
aria2
This program comes with no warranty. You must use this program at your own risk.
aria2 is a utility for downloading files. The supported protocols are HTTP(S), FTP, SFTP, BitTorrent, and Metalink. aria2 can download a file from multiple sources/protocols and tries to utilize your maximum download bandwidth. It supports downloading a file from HTTP(S)/FTP/SFTP and BitTorrent at the same time, while the data downloaded from HTTP(S)/FTP/SFTP is uploaded to the BitTorrent swarm. Using Metalink's chunk checksums, aria2 automatically validates chunks of data while downloading a file like BitTorrent.
The project page is located at https://aria2.github.io/.
See the aria2 Online Manual (Russian translation, Portuguese translation) to learn how to use aria2.
Here is a list of features:
Command-line interface
Download files through HTTP(S)/FTP/SFTP/BitTorrent
Segmented downloading
Metalink version 4 (RFC 5854) support(HTTP/FTP/SFTP/BitTorrent)
Metalink version 3.0 support(HTTP/FTP/SFTP/BitTorrent)
Metalink/HTTP (RFC 6249) support
HTTP/1.1 implementation
HTTP Proxy support
HTTP BASIC authentication support
HTTP Proxy authentication support
Well-known environment variables for proxy: http_proxy,https_proxy, ftp_proxy, all_proxy and no_proxy
HTTP gzip, deflate content encoding support
Verify peer using given trusted CA certificate in HTTPS
Client certificate authentication in HTTPS
Chunked transfer encoding support
Load Cookies from the file using the Firefox3 format, Chromium/Google Chrome and the Mozilla/Firefox (1.x/2.x)/Netscape format.
Save Cookies in the Mozilla/Firefox (1.x/2.x)/Netscape format.
Custom HTTP Header support
Persistent Connections support
FTP/SFTP through HTTP Proxy
Download/Upload speed throttling
BitTorrent extensions: Fast extension, DHT, PEX, MSE/PSE, Multi-Tracker, UDP tracker
BitTorrent WEB-Seeding. aria2 requests chunk more than piece size to reduce the request overhead. It also supports pipelined requests with piece size.
BitTorrent Local Peer Discovery
Rename/change the directory structure of BitTorrent downloads completely
JSON-RPC (over HTTP and WebSocket)/XML-RPC interface
Run as a daemon process
Selective download in multi-file torrent/Metalink
Chunk checksum validation in Metalink
Can disable segmented downloading in Metalink
Netrc support
Configuration file support
Download URIs found in a text file or stdin and the destination directory and output file name can be specified optionally
Parameterized URI support
IPv6 support with Happy Eyeballs
Disk cache to reduce disk activity
We use 3 numbers for the aria2 version: MAJOR.MINOR.PATCH. We will ship MINOR updates on the 15th of every month. We may skip a release if we have had no changes since the last release. The feature and documentation freeze happens 10 days before the release day (the 5th day of the month) for translation teams. We will raise an issue about the upcoming release around that day.
We may release PATCH releases between regular releases if we have security issues.
The MAJOR version will stay at 1 for the time being.
We maintain the source code at Github: https://github.com/aria2/aria2
To get the latest source code, run the following command:
$ git clone https://github.com/aria2/aria2.git
This will create an aria2 directory in your current directory and source files are stored there.
| features | dependency |
|---|---|
| HTTPS | OSX or GnuTLS or OpenSSL or Windows |
| SFTP | libssh2 |
| BitTorrent | None. Optional: libnettle+libgmp or libgcrypt or OpenSSL (see note) |
| Metalink | libxml2 or Expat. |
| Checksum | None. Optional: OSX or libnettle or libgcrypt or OpenSSL or Windows (see note) |
| gzip, deflate in HTTP | zlib |
| Async DNS | C-Ares |
| Firefox3/Chromium cookie | libsqlite3 |
| XML-RPC | libxml2 or Expat. |
| JSON-RPC over WebSocket | libnettle or libgcrypt or OpenSSL |
Note
libxml2 has precedence over Expat if both libraries are installed.
If you prefer Expat, run configure with --without-libxml2.
Note
On Apple OSX, OS-level SSL/TLS support will be preferred. Hence
neither GnuTLS nor OpenSSL is required on that platform. If you'd
like to disable this behavior, run configure with--without-appletls.
GnuTLS has precedence over OpenSSL if both libraries are installed.
If you prefer OpenSSL, run configure with --without-gnutls--with-openssl.
On Windows, there is SSL implementation available that is based on
the native Windows SSL capabilities (Schannel) and it will be
preferred. Hence neither GnuTLS nor OpenSSL is required on that
platform. If you'd like to disable this behavior, run configure
with --without-wintls.
Note
On Apple OSX, the OS-level checksum support will be preferred,
unless aria2 is configured with --without-appletls.
libnettle has precedence over libgcrypt if both libraries are
installed. If you prefer libgcrypt, run configure with--without-libnettle --with-libgcrypt. If OpenSSL is selected over
GnuTLS, neither libnettle nor libgcrypt will be used.
If none of the optional dependencies are installed, an internal implementation that only supports md5 and sha1 will be used.
On Windows, there is SSL implementation available that is based on
the native Windows capabilities and it will be preferred, unless
aria2 is configured with --without-wintls.
A user can have one of the following configurations for SSL and crypto libraries:
OpenSSL
GnuTLS + libgcrypt
GnuTLS + libnettle
Apple TLS (OSX only)
Windows TLS (Windows only)
You can disable BitTorrent and Metalink support by providing--disable-bittorrent and --disable-metalink to the configure
script respectively.
To enable async DNS support, you need c-ares.
c-ares: http://c-ares.haxx.se/
aria2 is primarily written in C++. Initially, it was written based on
C++98/C++03 standard features. We are now migrating aria2 to the C++11
standard. The current source code requires a C++11 aware compiler. For
well-known compilers, such as g++ and clang, the -std=c++11 or-std=c++0x flag must be supported.
To build aria2 from the source package, you need the following development packages (package name may vary depending on the distribution you use):
libgnutls-dev (Required for HTTPS, BitTorrent, Checksum support)
nettle-dev (Required for BitTorrent, Checksum support)
libgmp-dev (Required for BitTorrent)
libssh2-1-dev (Required for SFTP support)
libc-ares-dev (Required for async DNS support)
libxml2-dev (Required for Metalink support)
zlib1g-dev (Required for gzip, deflate decoding support in HTTP)
libsqlite3-dev (Required for Firefox3/Chromium cookie support)
pkg-config (Required to detect installed libraries)
You can use libgcrypt-dev instead of nettle-dev and libgmp-dev:
libgpg-error-dev (Required for BitTorrent, Checksum support)
libgcrypt-dev (Required for BitTorrent, Checksum support)
You can use libssl-dev instead of libgnutls-dev, nettle-dev, libgmp-dev, libgpg-error-dev and libgcrypt-dev:
libssl-dev (Required for HTTPS, BitTorrent, Checksum support)
You can use libexpat1-dev instead of libxml2-dev:
libexpat1-dev (Required for Metalink support)
On Fedora you need the following packages: gcc, gcc-c++, kernel-devel, libgcrypt-devel, libxml2-devel, openssl-devel, gettext-devel, cppunit
If you downloaded source code from a git repository, you have to install the following packages to get autoconf macros:
libxml2-dev
libcppunit-dev
autoconf
automake
autotools-dev
autopoint
libtool
And run the following command to generate configure script and other files necessary to build the program:
$ autoreconf -i
Also, you need Sphinx to build the man page.
If you are building aria2 for Mac OS X, take a look at the makerelease-osx.mk GNU Make makefile.
The quickest way to build aria2 is first to run configure script:
$ ./configure
To build statically linked aria2, use ARIA2_STATIC=yescommand-line option:
$ ./configure ARIA2_STATIC=yes
After configuration is done, run make to compile the program:
$ make
See Cross-compiling Windows binary to create a Windows binary. See Cross-compiling Android binary to create an Android binary.
The configure script checks available libraries and enables as many features as possible except for experimental features not enabled by default.
Since 1.1.0, aria2 checks the certificate of HTTPS servers by default.
If you build with OpenSSL or the recent version of GnuTLS which hasgnutls_certificate_set_x509_system_trust() function and the
library is properly configured to locate the system-wide CA
certificates store, aria2 will automatically load those certificates
at the startup. If it is not the case, I recommend supplying the path
to the CA bundle file. For example, in Debian the path to CA bundle
file is '/etc/ssl/certs/ca-certificates.crt' (in ca-certificates
package). This may vary depending on your distribution. You can give
it to configure script using --with-ca-bundle option:
$ ./configure --with-ca-bundle='/etc/ssl/certs/ca-certificates.crt' $ make
Without --with-ca-bundle option, you will encounter the error when
accessing HTTPS servers because the certificate cannot be verified
without the CA bundle. In such a case, you can specify the CA bundle file
using aria2's --ca-certificate option. If you don't have the CA bundle
file installed, then the last resort is to disable the certificate
validation using --check-certificate=false.
Using the native OSX (AppleTLS) and/or Windows (WinTLS) implementation
will automatically use the system certificate store, so--with-ca-bundle is not necessary and will be ignored when using
these implementations.
By default, the bash_completion file named aria2c is installed to
the directory $prefix/share/doc/aria2/bash_completion. To change
the install directory of the file, use --with-bashcompletiondiroption.
After a make, the executable is located at src/aria2c.
aria2 uses CppUnit for automated unit testing. To run the unit test:
$ make check
In this section, we describe how to build a Windows binary using a mingw-w64 (http://mingw-w64.org/doku.php) cross-compiler on Debian Linux. The MinGW (http://www.mingw.org/) may not be able to build aria2.
The easiest way to build Windows binary is using Dockerfile.mingw. See Dockerfile.mingw how to build a binary. If you cannot use Dockerfile, then continue to read the following paragraphs.
Basically, after compiling and installing depended libraries, you can
do cross-compile just passing appropriate --host option and
specifying CPPFLAGS, LDFLAGS, and PKG_CONFIG_LIBDIRvariables to configure. For convenience and to lower our own
development cost, we provide an easier way to configure the build
settings.
mingw-config script is a configure script wrapper for mingw-w64.
We use it to create official Windows build. This script assumes
the following libraries have been built for cross-compile:
c-ares
expat
sqlite3
zlib
libssh2
cppunit
Some environment variables can be adjusted to change build settings:
HOST
cross-compile to build programs to run on HOST. It defaults toi686-w64-mingw32. To build a 64bit binary, specifyx86_64-w64-mingw32.
PREFIX
Prefix to the directory where dependent libraries are installed. It
defaults to /usr/local/$HOST. -I$PREFIX/include will be
added to CPPFLAGS. -L$PREFIX/lib will be added toLDFLAGS. $PREFIX/lib/pkgconfig will be set toPKG_CONFIG_LIBDIR.
For example, to build a 64bit binary do this:
$ HOST=x86_64-w64-mingw32 ./mingw-config
If you want libaria2 dll with --enable-libaria2, then don't useARIA2_STATIC=yes and prepare the DLL version of external
libraries.
In this section, we describe how to build Android binary using Android NDK cross-compiler on Debian Linux.
At the time of this writing, Android NDK r21e should compile aria2 without errors.
android-config script is a configure script wrapper for Android
build. We use it to create an official Android build. This script
assumes the following libraries have been built for cross-compile:
c-ares
openssl
expat
zlib
libssh2
When building the above libraries, make sure that disable shared library and enable only static library. We are going to link those libraries statically.
android-config assumes that $ANDROID_HOME and $NDKenvironment variables are defined.
We currently use Android NDK r21e. $NDK should point to the
directory to Android NDK. The build tools will be found under$NDK/toolchains/llvm/prebuilt/linux-x86_64/bin/.
All the dependent libraries must be installed under$ANDROID_HOME/usr/local.
After android-config, run make to compile sources.
Sphinx is used to building the
documentation. aria2 man pages will be build when you run make if
they are not up-to-date. You can also build an HTML version of the aria2
man page by make html. The HTML version manual is also available
online (Russian
translation, Portuguese
translation).
The file name of the downloaded file is determined as follows:
single-file mode
If "name" key is present in .torrent file, the file name is the value of "name" key. Otherwise, the file name is the base name of .torrent file appended by ".file". For example, .torrent file is "test.torrent", then file name is "test.torrent.file". The directory to store the downloaded file can be specified by -d option.
multi-file mode
The complete directory/file structure mentioned in .torrent file is created. The directory to store the top directory of downloaded files can be specified by -d option.
Before download starts, a complete directory structure is created if
needed. By default, aria2 opens at most 100 files mentioned in
.torrent file, and directly writes to and reads from these files.
The number of files to open simultaneously can be controlled by--bt-max-open-files option.
aria2 supports mainline compatible DHT. By default, the routing table
for IPv4 DHT is saved to $XDG_CACHE_HOME/aria2/dht.dat and the
routing table for IPv6 DHT is saved to$XDG_CACHE_HOME/aria2/dht6.dat unless files exist at$HOME/.aria2/dht.dat or $HOME/.aria2/dht6.dat. aria2 uses the
same port number to listen on for both IPv4 and IPv6 DHT.
UDP tracker support is enabled when IPv4 DHT is enabled. The port
number of the UDP tracker is shared with DHT. Use --dht-listen-portoption to change the port number.
-o option is used to change the file name of .torrent file itself,
not a file name of a file in .torrent file. For this purpose, use--index-out option instead.
The port numbers that aria2 uses by default are 6881-6999 for TCP and UDP.
aria2 doesn't configure port-forwarding automatically. Please configure your router or firewall manually.
The maximum number of peers is 55. This limit may be exceeded when
the download rate is low. This download rate can be adjusted using--bt-request-peer-speed-limit option.
As of release 0.10.0, aria2 stops sending request messages after selective download completes.
The current implementation supports HTTP(S)/FTP/SFTP/BitTorrent. The other P2P protocols are ignored. Both Metalink4 (RFC 5854) and Metalink version 3.0 documents are supported.
For checksum verification, md5, sha-1, sha-224, sha-256, sha-384, and sha-512 are supported. If multiple hash algorithms are provided, aria2 uses a stronger one. If whole file checksum verification fails, aria2 doesn't retry the download and just exits with a non-zero return code.
The supported user preferences are version, language, location, protocol, and os.
If chunk checksums are provided in the Metalink file, aria2 automatically validates chunks of data during download. This behavior can be turned off by a command-line option.
If a signature is included in a Metalink file, aria2 saves it as a file after the completion of the download. The file name is download file name + ".sig". If the same file already exists, the signature file is not saved.
In Metalink4, a multi-file torrent could appear in metalink:metaurl element. Since aria2 cannot download 2 same torrents at the same time, aria2 groups files in metalink:file element which has the same BitTorrent metaurl, and downloads them from a single BitTorrent swarm. This is a basically multi-file torrent download with file selection, so the adjacent files which are not in Metalink document but share the same piece with the selected file are also created.
If relative URI is specified in metalink:url or metalink:metaurl
element, aria2 uses the URI of Metalink file as base URI to resolve
the relative URI. If relative URI is found in the Metalink file which is
read from the local disk, aria2 uses the value of --metalink-base-urioption as base URI. If this option is not specified, the relative URI
will be ignored.
The current implementation only uses rel=duplicate links. aria2
understands Digest header fields and check whether it matches the
digest value from other sources. If it differs, drop the connection.
aria2 also uses this digest value to perform checksum verification
after the download is finished. aria2 recognizes geo value. To tell aria2
which location you prefer, you can use --metalink-location option.
netrc support is enabled by default for HTTP(S)/FTP/SFTP. To disable netrc support, specify -n command-line option. Your .netrc file should have correct permissions(600).
The WebSocket server embedded in aria2 implements the specification defined in RFC 6455. The supported protocol version is 13.
The libaria2 is a C++ library that offers aria2 functionality to the
client code. Currently, libaria2 is not built by default. To enable
libaria2, use --enable-libaria2 configure option. By default,
only the shared library is built. To build a static library, use--enable-static configure option as well. See libaria2
documentation to know how to use API.
aria2 Online Manual
https://aria2.github.io/
RFC 959 FILE TRANSFER PROTOCOL (FTP)
RFC 1738 Uniform Resource Locators (URL)
RFC 2428 FTP Extensions for IPv6 and NATs
RFC 2616 Hypertext Transfer Protocol -- HTTP/1.1
RFC 3659 Extensions to FTP
RFC 3986 Uniform Resource Identifier (URI): Generic Syntax
RFC 4038 Application Aspects of IPv6 Transition
RFC 5854 The Metalink Download Description Format
RFC 6249 Metalink/HTTP: Mirrors and Hashes
RFC 6265 HTTP State Management Mechanism
RFC 6266 Use of the Content-Disposition Header Field in the Hypertext Transfer Protocol (HTTP)
RFC 6455 The WebSocket Protocol
RFC 6555 Happy Eyeballs: Success with Dual-Stack Hosts
The BitTorrent Protocol Specification
BitTorrent: DHT Protocol
BitTorrent: Fast Extension
BitTorrent: IPv6 Tracker Extension
BitTorrent: Extension for Peers to Send Metadata Files
BitTorrent: Extension Protocol
BitTorrent: Multitracker Metadata Extension
BitTorrent: UDP Tracker Protocol for BitTorrent and BitTorrent udp-tracker protocol specification.
BitTorrent: WebSeed - HTTP/FTP Seeding (GetRight style)
BitTorrent: Private Torrents
BitTorrent: BitTorrent DHT Extensions for IPv6
BitTorrent: Message Stream Encryption
Kademlia: A Peer-to-peer Information System Based on the XOR Metric
