IPFS身份管理和初始化本地仓库
由于IPFS网络是没有中心服务器的，各个节点之间的数据传输是需要识别各个节点的，并且要求各个节点的ID是唯一的，如果没有一定的生成规则，就带来了挑战。在IPFS中，IPFS节点ID是这样规定的。
1。节点要自己生成一个基于PKI(https://en.wikipedia.org/wiki/Public_key_infrastructure)的秘钥对。
2.对密钥对中的公钥做hash也就是HASH(节点公钥)，就得到了节点的ID
默认生成的节点秘钥配置放在文件夹：~/.ipfs/config ，如果你没有自定义IPFS_PATH的话。
例如我本机的
"Identity":{
**"PeerID"**:**"QmQeJWckGKS9C56NtyvqA3APsq4gbtS8YwPnLTb9ZT3dd4"**,
**"PrivKey"**:**"privateKey"**
},
说明：~/.ipfs/config内容狠多，只是抽取identity
疑问：
这里如果节点作恶了，我从新生成一对密钥对就OK拉 ！！！怎么办？
节点ID的使用，当两个节点需要通信的时候
1.交换两个节点的公钥
2.检测HASH(节点公钥)是否等于节点ID
3.如果检测不相等，就退出。
IPFS command 结构
IPFS每一个命令的结构大致如下
[图片上传失败...(image-f0edd7-1532334776759)]
IPFS 初始化流程
初始化命令
ipfs init
命令代码分析，主要入口文件：/Users/zhang/go/src/github.com/ipfs/go-ipfs/cmd/ipfs/init.go
init命令运行的时候
1.在postRun中检测是否配置文件所在的repo在是否存在repo.lock文件，有就代表ipfs的deamon进程存在，就退出（代码init.go 61行）
[图片上传失败...(image-7a1152-1532334776759)]
2.根据输入的options参数（可选参数中值得注意的是--bits,指定生成的秘钥的长度，默认2048 ,profile，指定生成的配置文件名称），执行doInit方法.
A。 在doInit先检测IPFS所在文件系统的读写权限。
B。 检测fsrepo是否存在了节点config文件
C。如果没有存在config，执行初始化流程如下：
细节：加密秘钥长度必须最少是2048，如果太小报错
a。调用libp2p-crypto库的GenerateKeyPair生成密钥对，加密方法RSA。其中私钥使用base64.StdEncoding.EncodeToString方法转换为字符串。公钥调用go-libp2p-peer的IDFromPublicKey方法得到字符串x，最终字符串x调用libp2p的IDB58Encode方法编码为字符串hash，这个hash就是节点ID
b。读取启动节点，也就是bootstrap peer，这些节点决定了本地节点启动的时候链接谁的问题。默认系统默认硬编码了如下节点。这些节点由IPFS官方来维护。
<pre class="ql-syntax ql-authorBlock-13003047 first-line ql-long-13003047" spellcheck="false" line="edtp" data-linenum="1">var DefaultBootstrapAddresses = []string{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="tcHw" data-linenum="2"> "/dnsaddr/bootstrap.libp2p.io/ipfs/QmNnooDu7bfjPFoTZYxMNLWUQJyrVwtbZg5gBMjTezGAJN",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="iuye" data-linenum="3"> "/dnsaddr/bootstrap.libp2p.io/ipfs/QmQCU2EcMqAqQPR2i9bChDtGNJchTbq5TbXJJ16u19uLTa",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="vaLq" data-linenum="4"> "/dnsaddr/bootstrap.libp2p.io/ipfs/QmbLHAnMoJPWSCR5Zhtx6BHJX9KiKNN6tpvbUcqanj75Nb",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="rWC5" data-linenum="5"> "/dnsaddr/bootstrap.libp2p.io/ipfs/QmcZf59bWwK5XFi76CZX8cbJ4BhTzzA3gU1ZjYZcYW3dwt",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="NZGE" data-linenum="6"> "/ip4/104.131.131.82/tcp/4001/ipfs/QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ", // mars.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="RltB" data-linenum="7"> "/ip4/104.236.179.241/tcp/4001/ipfs/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM", // pluto.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="T416" data-linenum="8"> "/ip4/128.199.219.111/tcp/4001/ipfs/QmSoLSafTMBsPKadTEgaXctDQVcqN88CNLHXMkTNwMKPnu", // saturn.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="M0Pc" data-linenum="9"> "/ip4/104.236.76.40/tcp/4001/ipfs/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64", // venus.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="nqTZ" data-linenum="10"> "/ip4/178.62.158.247/tcp/4001/ipfs/QmSoLer265NRgSp2LA3dPaeykiS1J6DifTC88f5uVQKNAd", // earth.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="3AWr" data-linenum="11"> "/ip6/2604:a880:1:20::203:d001/tcp/4001/ipfs/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM", // pluto.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="b9pj" data-linenum="12"> "/ip6/2400:6180:0:d0::151:6001/tcp/4001/ipfs/QmSoLSafTMBsPKadTEgaXctDQVcqN88CNLHXMkTNwMKPnu", // saturn.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="9h5K" data-linenum="13"> "/ip6/2604:a880:800:10::4a:5001/tcp/4001/ipfs/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64", // venus.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="NwDv" data-linenum="14"> "/ip6/2a03:b0c0:0:1010::23:1001/tcp/4001/ipfs/QmSoLer265NRgSp2LA3dPaeykiS1J6DifTC88f5uVQKNAd", // earth.i.ipfs.io</pre>
<pre class="ql-syntax ql-authorBlock-13003047 last-line ql-long-13003047" spellcheck="false" line="DABt" data-linenum="15">}</pre>
c。读取数据存储默认配置文件DefaultDatastoreConfig，代码： src/github.com/ipfs/go-ipfs/repo/config/init.go 25行。
数据存储
数据存储是数据存储和数据库访问的通用抽象层。它是一个简单的API，其目的是使应用程序开发以数据不可知的方式进行，允许在不改变应用程序代码的情况下无缝地交换数据存储。因此，您可以利用具有不同强度的不同数据存储，而无需将应用程序在整个生命周期内提交给一个数据存储。
代码库
https://github.com/ipfs/go-datastore
配置文件如下
<pre class="ql-syntax ql-authorBlock-13003047 first-line ql-long-13003047" spellcheck="false" line="sA3L" data-linenum="1">func DefaultDatastoreConfig() Datastore {</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="OGvo" data-linenum="2"> return Datastore{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="xdl4" data-linenum="3"> StorageMax: "10GB",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="gX4x" data-linenum="4"> StorageGCWatermark: 90, // 90%</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="KFmk" data-linenum="5"> GCPeriod: "1h",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="axEP" data-linenum="6"> BloomFilterSize: 0,</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Gg72" data-linenum="7"> Spec: map[string]interface{}{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="gRjH" data-linenum="8"> "type": "mount",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="6KDW" data-linenum="9"> "mounts": []interface{}{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="qm6h" data-linenum="10"> map[string]interface{}{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="HTM0" data-linenum="11"> "mountpoint": "/blocks",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="JYuT" data-linenum="12"> "type": "measure",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Cj74" data-linenum="13"> "prefix": "flatfs.datastore",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="QUK9" data-linenum="14"> "child": map[string]interface{}{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="skQk" data-linenum="15"> "type": "flatfs",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="ZBtd" data-linenum="16"> "path": "blocks",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="ZajB" data-linenum="17"> "sync": true,</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="A7it" data-linenum="18"> "shardFunc": "/repo/flatfs/shard/v1/next-to-last/2",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="ZNCE" data-linenum="19"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Ptdr" data-linenum="20"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="mVIt" data-linenum="21"> map[string]interface{}{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="okWv" data-linenum="22"> "mountpoint": "/",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="XMu2" data-linenum="23"> "type": "measure",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="qPBJ" data-linenum="24"> "prefix": "leveldb.datastore",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="sQ5z" data-linenum="25"> "child": map[string]interface{}{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="nvjh" data-linenum="26"> "type": "levelds",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="jIFh" data-linenum="27"> "path": "datastore",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="7z4Z" data-linenum="28"> "compression": "none",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Eub7" data-linenum="29"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="H74N" data-linenum="30"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="nEy1" data-linenum="31"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="s3Ji" data-linenum="32"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="XJa2" data-linenum="33"> }</pre>
<pre class="ql-syntax ql-authorBlock-13003047 last-line ql-long-13003047" spellcheck="false" line="oM5x" data-linenum="34">}</pre>
默认存储空间10G，每小时一次GC，挂载点2个，一个是leveldb一个是flatfs，应该也是可以配置的。
d。读取本地地址默认配置，代码位置 src/github.com/ipfs/go-ipfs/repo/config/init.go 101行。
配置如下
<pre class="ql-syntax ql-authorBlock-13003047 first-line ql-long-13003047" spellcheck="false" line="Emy3" data-linenum="1">func addressesConfig() Addresses {</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="tHh7" data-linenum="2"> return Addresses{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="0vxN" data-linenum="3"> Swarm: []string{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="FDP1" data-linenum="4"> "/ip4/0.0.0.0/tcp/4001",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="aQsW" data-linenum="5"> // "/ip4/0.0.0.0/udp/4002/utp", // disabled for now.</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="lDIE" data-linenum="6"> "/ip6/::/tcp/4001",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="unRJ" data-linenum="7"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="msYH" data-linenum="8"> Announce: []string{},</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="aUkp" data-linenum="9"> NoAnnounce: []string{},</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="k3hq" data-linenum="10"> API: "/ip4/127.0.0.1/tcp/5001",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="KlhJ" data-linenum="11"> Gateway: "/ip4/127.0.0.1/tcp/8080",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="RiJh" data-linenum="12"> }</pre>
<pre class="ql-syntax ql-authorBlock-13003047 last-line ql-long-13003047" spellcheck="false" line="Ynce" data-linenum="13">}</pre>
可见，本地Swarm监听4001端口，使用这个端口和其他节点通信。支持IPV4和IPV6,默认不支持UDP方式。本地Api网关，127.0.0.1:5001 ，本地资源网关127.0.0.1：8080 。
e。配置组播配置
<pre class="ql-syntax ql-authorBlock-13003047 first-line ql-long-13003047" spellcheck="false" line="Puog" data-linenum="1">Discovery: Discovery{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Uigh" data-linenum="2"> MDNS: MDNS{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="gIHG" data-linenum="3"> Enabled: true,</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="1NSa" data-linenum="4"> Interval: 10,</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="JH7j" data-linenum="5"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 last-line ql-long-13003047" spellcheck="false" line="ANOC" data-linenum="6">},</pre>
使用MDNS协议来组网。在一个没有常规DNS服务器的小型网络内，可以使用mDNS来实现类似DNS的编程接口、包格式和操作语义。具体：https://www.cnblogs.com/yuweifeng/p/6409182.html
f。设置路由
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="qCNI" data-linenum="2">Routing: Routing{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="KBZP" data-linenum="3"> Type: "dht",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 last-line ql-long-13003047" spellcheck="false" line="5tlX" data-linenum="4">},</pre>
g。设置挂载点
<pre class="ql-syntax ql-authorBlock-13003047 first-line ql-long-13003047" spellcheck="false" line="fi60" data-linenum="1">Mounts: Mounts{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="FUhl" data-linenum="2"> IPFS: "/ipfs",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="qy2N" data-linenum="3"> IPNS: "/ipns",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 last-line ql-long-13003047" spellcheck="false" line="IoNJ" data-linenum="4">},</pre>
h。设置资源网管headers等信息
<pre class="ql-syntax ql-authorBlock-13003047 first-line ql-long-13003047" spellcheck="false" line="Gh9w" data-linenum="1">Gateway: Gateway{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="WCrQ" data-linenum="2"> RootRedirect: "",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="ScaG" data-linenum="3"> Writable: false,</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="aBpD" data-linenum="4"> PathPrefixes: []string{},</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="AegP" data-linenum="5"> HTTPHeaders: map[string][]string{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Rbr9" data-linenum="6"> "Access-Control-Allow-Origin": []string{"*"},</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="HBwW" data-linenum="7"> "Access-Control-Allow-Methods": []string{"GET"},</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Ji5k" data-linenum="8"> "Access-Control-Allow-Headers": []string{"X-Requested-With", "Range"},</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Oa9W" data-linenum="9"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 last-line ql-long-13003047" spellcheck="false" line="9HxT" data-linenum="10">},</pre>
i。读取和设置swarm配置
<pre class="ql-syntax ql-authorBlock-13003047 first-line ql-long-13003047" spellcheck="false" line="voQp" data-linenum="1">Swarm: SwarmConfig{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="yQZK" data-linenum="2"> ConnMgr: ConnMgr{</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="FHMs" data-linenum="3"> LowWater: DefaultConnMgrLowWater,</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="4rAh" data-linenum="4"> HighWater: DefaultConnMgrHighWater,</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="v54f" data-linenum="5"> GracePeriod: DefaultConnMgrGracePeriod.String(),</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="Vn1k" data-linenum="6"> Type: "basic",</pre>
<pre class="ql-syntax ql-authorBlock-13003047 ql-long-13003047" spellcheck="false" line="DCuL" data-linenum="7"> },</pre>
<pre class="ql-syntax ql-authorBlock-13003047 last-line ql-long-13003047" spellcheck="false" line="G4R3" data-linenum="8">},</pre>
D。解析配置文件
E。真正调用：fsrepo.Init(repoRoot, conf) 代码：161行。
a。写入C步骤生成的config文件到repo路径下面
b。初始化datastore空间
c。在repo下面写入版本WriteVersion
F。如果参数默认，调用addDefaultAssets写入默认readme文件到本地repo
到此为止，infs init 流程结束。
Multihash
https://github.com/multiformats/multihash
https://multiformats.io/multihash/#implementations
为何要有multihash？
本质上为了升级方便，现有的各种加密算法，不能保证以后不出问题。第三方如果依赖于使用的hash算法的名字和长度，以后升级就会带来各种各样的问题。为此，multihash就出来了，它采用TLV (type-length-value) 的方式抽象了Hash的使用~ 解决了依赖于hash 函数和 长度的问题。
在IPFS中使用multihas的地方主要是ipfs object分块和地址这里。
网友评论