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works without --local

This commit is contained in:
Zack Scholl 2018-04-24 07:46:07 -07:00
parent bea025fbe4
commit 2bd8504a57
3 changed files with 192 additions and 139 deletions

View file

@ -175,40 +175,52 @@ func (c *Connection) Run() error {
} }
} }
if c.Local && c.Server == "" { if c.IsSender {
c.Server = "localhost" if c.Code == "" {
p, err := peerdiscovery.New(peerdiscovery.Settings{ c.Code = GetRandomName()
}
log.Debug("settings payload to ", c.Code)
p, _ := peerdiscovery.New(peerdiscovery.Settings{
Limit: 1, Limit: 1,
TimeLimit: 600 * time.Second, TimeLimit: 600 * time.Second,
Delay: 500 * time.Millisecond, Delay: 50 * time.Millisecond,
Payload: []byte(c.Code), Payload: []byte(c.Code),
}) })
if err != nil { go func() {
return err discovered, _ := p.Discover()
} if len(discovered) > 0 {
if c.IsSender { log.Debugf("discovered by '%+v'", discovered[0])
go p.Discover() c.runClient("localhost")
} else { os.Exit(1)
fmt.Print("Finding local croc relay...") } else {
discovered, err := p.Discover() log.Debug("discovered by no one")
if err != nil {
return err
}
if len(discovered) == 0 {
return errors.New("could not find server")
} }
}()
} else {
p, _ := peerdiscovery.New(peerdiscovery.Settings{
Limit: 1,
TimeLimit: 1 * time.Second,
Delay: 50 * time.Millisecond,
Payload: []byte(c.Code),
})
fmt.Print("Finding local croc relay...")
discovered, _ := p.Discover()
if len(discovered) > 0 {
c.Server = discovered[0].Address c.Server = discovered[0].Address
fmt.Println(discovered[0].Address) fmt.Println(discovered[0].Address)
c.Code = string(discovered[0].Payload) c.Code = string(discovered[0].Payload)
log.Debugf("discovered code '%s'", c.Code)
time.Sleep(200 * time.Millisecond)
} }
} }
if c.Local && c.IsSender { if c.IsSender {
log.Debug("starting relay") log.Debug("starting relay in case local connections")
relay := NewRelay(&AppConfig{ relay := NewRelay(&AppConfig{
Debug: c.Debug, Debug: c.Debug,
}) })
go relay.Run() go relay.Run()
time.Sleep(200 * time.Millisecond)
} }
log.Debug("checking code validity") log.Debug("checking code validity")
@ -288,14 +300,13 @@ func (c *Connection) Run() error {
} else { } else {
fmt.Fprintf(os.Stderr, "Code is: %s\n", c.Code) fmt.Fprintf(os.Stderr, "Code is: %s\n", c.Code)
} }
} }
return c.runClient() return c.runClient(c.Server)
} }
// runClient spawns threads for parallel uplink/downlink via TCP // runClient spawns threads for parallel uplink/downlink via TCP
func (c *Connection) runClient() error { func (c *Connection) runClient(serverName string) error {
c.HashedCode = Hash(c.Code) c.HashedCode = Hash(c.Code)
c.NumberOfConnections = MAX_NUMBER_THREADS c.NumberOfConnections = MAX_NUMBER_THREADS
var wg sync.WaitGroup var wg sync.WaitGroup
@ -323,12 +334,12 @@ func (c *Connection) runClient() error {
go func(id int) { go func(id int) {
defer wg.Done() defer wg.Done()
port := strconv.Itoa(27001 + id) port := strconv.Itoa(27001 + id)
connection, err := net.Dial("tcp", c.Server+":"+port) connection, err := net.Dial("tcp", serverName+":"+port)
if err != nil { if err != nil {
if c.Server == "cowyo.com" { if serverName == "cowyo.com" {
fmt.Println("\nCheck http://bit.ly/croc-relay to see if the public server is down or contact the webmaster: @yakczar") fmt.Println("\nCheck http://bit.ly/croc-relay to see if the public server is down or contact the webmaster: @yakczar")
} else { } else {
fmt.Fprintf(os.Stderr, "\nCould not connect to relay %s\n", c.Server) fmt.Fprintf(os.Stderr, "\nCould not connect to relay %s\n", serverName)
} }
os.Exit(1) os.Exit(1)
} }

View file

@ -1,113 +1,155 @@
<p align="center"> <p align="center">
<img <img
src="https://user-images.githubusercontent.com/6550035/31846899-2b8a7034-b5cf-11e7-9643-afe552226c59.png" src="https://user-images.githubusercontent.com/6550035/31846899-2b8a7034-b5cf-11e7-9643-afe552226c59.png"
width="100%" border="0" alt="croc"> width="100%" border="0" alt="croc">
<br> <br>
<a href="https://github.com/schollz/croc/releases/latest"><img src="https://img.shields.io/badge/version-0.1.0-green.svg?style=flat-square" alt="Version"></a> <a href="https://travis-ci.org/schollz/croc"><img src="https://travis-ci.org/schollz/croc.svg?branch=master" alt="Build Status"></a>
<a href="https://gitter.im/schollz/croc?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=body_badge"><img src="https://img.shields.io/badge/chat-on%20gitter-green.svg?style=flat-square" alt="Version"></a> <a href="https://github.com/schollz/croc/releases/latest"><img src="https://img.shields.io/badge/version-1.0.0-brightgreen.svg?style=flat-square" alt="Version"></a>
</p> <a href="https://goreportcard.com/report/github.com/schollz/croc"><img src="https://goreportcard.com/badge/github.com/schollz/croc" alt="Go Report Card"></a>
</p>
<p align="center">Secure transfer of stuff from one side of the internet to the other.</p>
<p align="center">Easily and securely transfer stuff from one computer to another.</p>
This is more or less (but mostly *less*) a Golang port of [@warner's](https://github.com/warner) [*magic-wormhole*](https://github.com/warner/magic-wormhole) which allows you to directly transfer files and folders between computers. I decided to make this because I wanted to send my friend Jessie a file using *magic-wormhole* and when I told Jessie how to install the dependencies she made this face: :sob:. So, nominally, *croc* does the same thing (encrypted file transfer directly between computers) without dependencies so you can just double-click on your computer, even if you use Windows.
*croc* allows any two computers to directly and securely transfer files and folders. When sending a file, *croc* generates a random code phrase which must be shared with the recipient so they can receive the file. The code phrase encrypts all data and metadata and also serves to authorize the connection between the two computers in a intermediary relay. The relay connects the TCP ports between the two computers and does not store any information (and all information passing through it is encrypted).
**Don't we have enough open-source peer-to-peer file-transfer utilities?**
I hear you asking, *Why another open-source peer-to-peer file transfer utilities?* [There](https://github.com/cowbell/sharedrop) [are](https://github.com/webtorrent/instant.io) [great](https://github.com/kern/filepizza) [tools](https://github.com/warner/magic-wormhole) [that](https://github.com/zerotier/toss) [already](https://github.com/ipfs/go-ipfs) [do](https://github.com/zerotier/toss) [this](https://github.com/nils-werner/zget). But, after review, [I found it was useful to make another](https://schollz.github.io/sending-a-file/). Namely, *croc* has no dependencies (just [download a binary and run](https://github.com/schollz/croc/releases/latest)), it works on any operating system, and its blazingly fast because it does parallel transfer over multiple TCP ports.
[There](https://github.com/cowbell/sharedrop) [are](https://github.com/webtorrent/instant.io) [great](https://github.com/kern/filepizza) [tools](https://github.com/warner/magic-wormhole) [that](https://github.com/zerotier/toss) [already](https://github.com/ipfs/go-ipfs) [do](https://github.com/zerotier/toss) [this](https://github.com/nils-werner/zget). But, no we don't, because after review, [I found it was useful to make a new one](https://schollz.github.io/sending-a-file/).
# Example
# Example
_These two gifs should run in sync if you force-reload (Ctl+F5)_
_These two gifs should run in sync if you force-reload (Ctl+F5)_
**Sender:**
**Sender:**
![send](https://raw.githubusercontent.com/schollz/croc/master/logo/sender.gif)
![send](https://user-images.githubusercontent.com/6550035/31864532-ad80c6ae-b71b-11e7-91f9-bcba8143d3cf.gif)
**Receiver:**
**Receiver:**
![receive](https://raw.githubusercontent.com/schollz/croc/master/logo/receiver.gif)
![receive](https://user-images.githubusercontent.com/6550035/31864531-ad6e22c4-b71b-11e7-901a-02a210057cf1.gif)
**Sender:**
**Sender:**
```
``` $ croc -send some-file-or-folder
$ croc -send croc.exe Sending 4.4 MB file named 'some-file-or-folder'
Sending 4.4 MB file named 'croc.exe' Code is: cement-galaxy-alpha
Code is: 4-cement-galaxy-alpha
Sending (->[1]63982)..
Sending (->24.65.41.43:50843).. 89% |███████████████████████████████████ | [12s:1s]
0s [==========================================================] 100% File sent (2.6 MB/s)
File sent. ```
```
**Receiver:**
**Receiver:**
```
``` $ croc
$ croc Enter receive code: cement-galaxy-alpha
Enter receive code: 4-cement-galaxy-alpha Receiving file (4.4 MB) into: some-file-or-folder
Receiving file (4.4 MB) into: croc.exe ok? (y/n): y
ok? (y/n): y
Receiving (<-[1]63975)..
Receiving (<-50.32.38.188:50843).. 97% |██████████████████████████████████████ | [13s:0s]
0s [==========================================================] 100% Received file written to some-file-or-folder (2.6 MB/s)
Received file written to croc.exe ```
```
Note, by default, you don't need any arguments for receiving! This makes it possible for you to just double click the executable to run (nice for those of us that aren't computer wizards).
Note, by default, you don't need any arguments for receiving! This makes it possible for you to just double click the executable to run (nice for those of us that aren't computer wizards).
## Transfering files between local computers
# Install
Its even easier if you want to transfer files between two computers on the same network.
[Download the latest release for your system](https://github.com/schollz/croc/releases/latest).
**Sender:**
Or, you can [install Go](https://golang.org/dl/) and build from source with `go get github.com/schollz/croc`.
```
$ croc -send some-file-or-folder -local
```
# How does it work?
**Receiver:**
*croc* is similar to [magic-wormhole](https://github.com/warner/magic-wormhole#design) in spirit and design. Like *magic-wormhole*, *croc* generates a code phrase for you to share with your friend which allows secure end-to-end transfering of files and folders through a intermediary relay that connects the TCP ports between the two computers.
```
In *croc*, code phrase is 16 random bits that are [menemonic encoded](http://web.archive.org/web/20101031205747/http://www.tothink.com/mnemonic/) plus a prepended integer to specify number of threads. This code phrase is hashed using sha256 and sent to a relay which maps that key to that connection. When the relay finds a matching key for both the receiver and the sender (i.e. they both have the same code phrase), then the sender transmits the encrypted metadata to the receiver through the relay. Then the receiver decrypts and reviews the metadata (file name, size), and chooses whether to consent to the transfer. $ croc -local
```
After the receiver consents to the transfer, the sender transmits encrypted data through the relay. The relay setups up [Go channels](https://golang.org/doc/effective_go.html?h=chan#channels) for each connection which pipes all the data incoming from that sender's connection out to the receiver's connection. After the transmission the channels are destroyed and all the connection and meta data information is wiped from the relay server. The encrypted file data never is stored on the relay.
Yes, when you run locally you don't even need to use a code. When you run locally, the *croc* receiver will use UDP broadcast packets to automatically find the correct IP address and code to use to transfer the file. When run locally, there is also no encryption so it is even faster.
**Encryption**
**Sender:**
Encryption uses PBKDF2 (see [RFC2898](http://www.ietf.org/rfc/rfc2898.txt)) where the code phrase shared between the sender and receiver is used as the passphrase. For each of the two encrypted data blocks (metadata stored on relay server, and file data transmitted), a random 8-byte salt is used and a IV is generated according to [NIST Recommendation for Block ciphers, Section 8.2](http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf).
![Running locally](https://raw.githubusercontent.com/schollz/croc/master/logo/1.gif)
**Decryption** **Receiver:**
On the receiver's computer, each piece of received encrypted data is written to a separate file. These files are concatenated and then decrypted. The hash of the decrypted file is then checked against the hash transmitted from the sender (part of the meta data block). ![Running locally](https://raw.githubusercontent.com/schollz/croc/master/logo/2.gif)
## Run your own relay ## Using *croc* in pipes
*croc* relies on a TCP relay to staple the parallel incoming and outgoing connections. The relay temporarily stores connection information and the encrypted meta information. The default uses a public relay at, `cowyo.com`, which has no guarantees except that I guarantee to turn if off as soon as it gets abused ([click here to check the current status of the public relay](https://stats.uptimerobot.com/lOwJYIgRm)). You can easily use *croc* in pipes when you need to send data through stdin or get data from stdout.
I recommend you run your own relay, it is very easy. On your server, `your-server.com`, just run **Sender:**
``` ```
$ croc -relay $ cat some_file_or_folder | croc
``` ```
Now, when you use *croc* to send and receive you should add `-server your-server.com` to use your relay server. In this case *croc* will automatically use the stdin data and send and assign a filename like "croc-stdin-123456789".
_Note:_ If you are behind a firewall, make sure to open up TCP ports 27001-27009. **Receiver:**
# Contribute ```
$ croc --code code-phrase --yes --stdout | more
I am awed by all the [great contributions](#acknowledgements) made! If you feel like contributing, in any way, by all means you can send an Issue, a PR, ask a question, or tweet me ([@yakczar](http://ctt.ec/Rq054)). ```
# License Here the reciever specified the code (`--code`) so it will not be prompted, and also specified `--yes` so the file will be automatically accepted. The output goes to stdout when flagged with `--stdout`.
MIT
# Install
# Acknowledgements
[Download the latest release for your system](https://github.com/schollz/croc/releases/latest).
Thanks...
Or, you can [install Go](https://golang.org/dl/) and build from source with `go get github.com/schollz/croc`.
- ...[@warner](https://github.com/warner) for the [idea](https://github.com/warner/magic-wormhole).
- ...[@tscholl2](https://github.com/tscholl2) for the [encryption gists](https://gist.github.com/tscholl2/dc7dc15dc132ea70a98e8542fefffa28).
- ...[@skorokithakis](https://github.com/skorokithakis) for [code on proxying two connections](https://www.stavros.io/posts/proxying-two-connections-go/). # How does it work?
- ...for making pull requests [@Girbons](https://github.com/Girbons), [@techtide](https://github.com/techtide), [@heymatthew](https://github.com/heymatthew), [@Lunsford94](https://github.com/Lunsford94), [@lummie](https://github.com/lummie), [@jesuiscamille](https://github.com/jesuiscamille), [@threefjord](https://github.com/threefjord), [@marcossegovia](https://github.com/marcossegovia), [@csleong98](https://github.com/csleong98), [@afotescu](https://github.com/afotescu)!
*croc* is similar to [magic-wormhole](https://github.com/warner/magic-wormhole#design) in spirit and design. Like *magic-wormhole*, *croc* generates a code phrase for you to share with your friend which allows secure end-to-end transfering of files and folders through a intermediary relay that connects the TCP ports between the two computers.
In *croc*, code phrase is 16 random bits that are [menemonic encoded](http://web.archive.org/web/20101031205747/http://www.tothink.com/mnemonic/). This code phrase is hashed using sha256 and sent to a relay which maps that key to that connection. When the relay finds a matching key for both the receiver and the sender (i.e. they both have the same code phrase), then the sender transmits the encrypted metadata to the receiver through the relay. Then the receiver decrypts and reviews the metadata (file name, size), and chooses whether to consent to the transfer.
After the receiver consents to the transfer, the sender transmits encrypted data through the relay. The relay setups up [Go channels](https://golang.org/doc/effective_go.html?h=chan#channels) for each connection which pipes all the data incoming from that sender's connection out to the receiver's connection. After the transmission the channels are destroyed and all the connection and meta data information is wiped from the relay server. The encrypted file data never is stored on the relay.
**Encryption**
Encryption uses pbkdf2 (see [RFC2898](http://www.ietf.org/rfc/rfc2898.txt)) where the code phrase shared between the sender and receiver is used as the passphrase. For each of the two encrypted data blocks (metadata stored on relay server, and file data transmitted), a random 8-byte salt is used and a IV is generated according to [NIST Recommendation for Block ciphers, Section 8.2](http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf).
**Decryption**
On the receiver's computer, each piece of received encrypted data is written to a separate file. These files are concatenated and then decrypted. The hash of the decrypted file is then checked against the hash transmitted from the sender (part of the meta data block).
## Run your own relay
*croc* relies on a TCP relay to staple the parallel incoming and outgoing connections. The relay temporarily stores connection information and the encrypted meta information. The default uses a public relay at, `cowyo.com`, which has a 30-day uptime of 99.989% ([click here to check the current status of the public relay](https://stats.uptimerobot.com/lOwJYIgRm)).
You can also run your own relay, it is very easy. On your server, `your-server.com`, just run
```
$ croc -relay
```
Now, when you use *croc* to send and receive you should add `-server your-server.com` to use your relay server. Make sure to open up TCP ports 27001-27009.
# Contribute
I am awed by all the [great contributions](#acknowledgements) made! If you feel like contributing, in any way, by all means you can send an Issue, a PR, ask a question, or tweet me ([@yakczar](http://ctt.ec/Rq054)).
# License
MIT
# Acknowledgements
Thanks...
- ...[@warner](https://github.com/warner) for the [idea](https://github.com/warner/magic-wormhole).
- ...[@tscholl2](https://github.com/tscholl2) for the [encryption gists](https://gist.github.com/tscholl2/dc7dc15dc132ea70a98e8542fefffa28).
- ...[@skorokithakis](https://github.com/skorokithakis) for [code on proxying two connections](https://www.stavros.io/posts/proxying-two-connections-go/).
- ...for making pull requests [@Girbons](https://github.com/Girbons), [@techtide](https://github.com/techtide), [@heymatthew](https://github.com/heymatthew), [@Lunsford94](https://github.com/Lunsford94), [@lummie](https://github.com/lummie), [@jesuiscamille](https://github.com/jesuiscamille), [@threefjord](https://github.com/threefjord), [@marcossegovia](https://github.com/marcossegovia), [@csleong98](https://github.com/csleong98), [@afotescu](https://github.com/afotescu), [@callmefever](https://github.com/callmefever), [@El-JojA](https://github.com/El-JojA), [@anatolyyyyyy](https://github.com/anatolyyyyyy), [@goggle](https://github.com/goggle), [@smileboywtu](https://github.com/smileboywtu)!

View file

@ -188,7 +188,7 @@ func (p *PeerDiscovery) Discover() (discoveries []Discovered, err error) {
} }
const ( const (
maxDatagramSize = 8192 maxDatagramSize = 65507
) )
// Listen binds to the UDP address and port given and writes packets received // Listen binds to the UDP address and port given and writes packets received