helpers.go 18 KB

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  1. //TODO: Consider restructuring this file/folder "github.com/gorilla/handlers"
  2. //It may make more sense to split into different files and not call it "helpers"
  3. package functions
  4. import (
  5. "encoding/base64"
  6. "encoding/json"
  7. "errors"
  8. "fmt"
  9. "log"
  10. "math/rand"
  11. "net"
  12. "strings"
  13. "time"
  14. "github.com/gravitl/netmaker/database"
  15. "github.com/gravitl/netmaker/models"
  16. "github.com/gravitl/netmaker/servercfg"
  17. )
  18. func CheckEndpoint(endpoint string) bool {
  19. endpointarr := strings.Split(endpoint, ":")
  20. return len(endpointarr) == 2
  21. }
  22. func PrintUserLog(username string, message string, loglevel int) {
  23. log.SetFlags(log.Flags() &^ (log.Llongfile | log.Lshortfile))
  24. if int32(loglevel) <= servercfg.GetVerbose() && servercfg.GetVerbose() != 0 {
  25. log.Println(username, message)
  26. }
  27. }
  28. func ParseNetwork(value string) (models.Network, error) {
  29. var network models.Network
  30. err := json.Unmarshal([]byte(value), &network)
  31. return network, err
  32. }
  33. func ParseNode(value string) (models.Node, error) {
  34. var node models.Node
  35. err := json.Unmarshal([]byte(value), &node)
  36. return node, err
  37. }
  38. func ParseExtClient(value string) (models.ExtClient, error) {
  39. var extClient models.ExtClient
  40. err := json.Unmarshal([]byte(value), &extClient)
  41. return extClient, err
  42. }
  43. func ParseIntClient(value string) (models.IntClient, error) {
  44. var intClient models.IntClient
  45. err := json.Unmarshal([]byte(value), &intClient)
  46. return intClient, err
  47. }
  48. //Takes in an arbitrary field and value for field and checks to see if any other
  49. //node has that value for the same field within the network
  50. func GetUser(username string) (models.User, error) {
  51. var user models.User
  52. record, err := database.FetchRecord(database.USERS_TABLE_NAME, username)
  53. if err != nil {
  54. return user, err
  55. }
  56. if err = json.Unmarshal([]byte(record), &user); err != nil {
  57. return models.User{}, err
  58. }
  59. return user, err
  60. }
  61. func SliceContains(slice []string, item string) bool {
  62. set := make(map[string]struct{}, len(slice))
  63. for _, s := range slice {
  64. set[s] = struct{}{}
  65. }
  66. _, ok := set[item]
  67. return ok
  68. }
  69. func CreateServerToken(netID string) (string, error) {
  70. var network models.Network
  71. var accesskey models.AccessKey
  72. network, err := GetParentNetwork(netID)
  73. if err != nil {
  74. return "", err
  75. }
  76. var accessToken models.AccessToken
  77. servervals := models.ServerConfig{
  78. APIConnString: "127.0.0.1:" + servercfg.GetAPIPort(),
  79. GRPCConnString: "127.0.0.1:" + servercfg.GetGRPCPort(),
  80. GRPCSSL: "off",
  81. }
  82. accessToken.ServerConfig = servervals
  83. accessToken.ClientConfig.Network = netID
  84. accessToken.ClientConfig.Key = GenKey()
  85. accesskey.Name = GenKeyName()
  86. accesskey.Value = accessToken.ClientConfig.Key
  87. accesskey.Uses = 1
  88. tokenjson, err := json.Marshal(accessToken)
  89. if err != nil {
  90. return accesskey.AccessString, err
  91. }
  92. accesskey.AccessString = base64.StdEncoding.EncodeToString([]byte(tokenjson))
  93. network.AccessKeys = append(network.AccessKeys, accesskey)
  94. if data, err := json.Marshal(network); err != nil {
  95. return "", err
  96. } else {
  97. database.Insert(netID, string(data), database.NETWORKS_TABLE_NAME)
  98. }
  99. return accesskey.AccessString, nil
  100. }
  101. func GetPeersList(networkName string) ([]models.PeersResponse, error) {
  102. var peers []models.PeersResponse
  103. collection, err := database.FetchRecords(database.NODES_TABLE_NAME)
  104. if err != nil {
  105. return peers, err
  106. }
  107. for _, value := range collection {
  108. var peer models.PeersResponse
  109. err := json.Unmarshal([]byte(value), &peer)
  110. if err != nil {
  111. continue // try the rest
  112. }
  113. peers = append(peers, peer)
  114. }
  115. return peers, err
  116. }
  117. func GetIntPeersList() ([]models.PeersResponse, error) {
  118. var peers []models.PeersResponse
  119. records, err := database.FetchRecords(database.INT_CLIENTS_TABLE_NAME)
  120. if err != nil {
  121. return peers, err
  122. }
  123. // parse the peers
  124. for _, value := range records {
  125. var peer models.PeersResponse
  126. err := json.Unmarshal([]byte(value), &peer)
  127. if err != nil {
  128. log.Fatal(err)
  129. }
  130. // add the node to our node array
  131. //maybe better to just return this? But then that's just GetNodes...
  132. peers = append(peers, peer)
  133. }
  134. return peers, err
  135. }
  136. func GetServerIntClient() (*models.IntClient, error) {
  137. intClients, err := database.FetchRecords(database.INT_CLIENTS_TABLE_NAME)
  138. for _, value := range intClients {
  139. var intClient models.IntClient
  140. err = json.Unmarshal([]byte(value), &intClient)
  141. if err != nil {
  142. return nil, err
  143. }
  144. if intClient.IsServer == "yes" && intClient.Network == "comms" {
  145. return &intClient, nil
  146. }
  147. }
  148. return nil, err
  149. }
  150. func NetworkExists(name string) (bool, error) {
  151. var network string
  152. var err error
  153. if network, err = database.FetchRecord(database.NETWORKS_TABLE_NAME, name); err != nil {
  154. return false, err
  155. }
  156. return len(network) > 0, nil
  157. }
  158. func GetRecordKey(id string, network string) (string, error) {
  159. if id == "" || network == "" {
  160. return "", errors.New("unable to get record key")
  161. }
  162. return id + "###" + network, nil
  163. }
  164. func UpdateNetworkNodeAddresses(networkName string) error {
  165. collections, err := database.FetchRecords(database.NODES_TABLE_NAME)
  166. if err != nil {
  167. return err
  168. }
  169. for _, value := range collections {
  170. var node models.Node
  171. err := json.Unmarshal([]byte(value), &node)
  172. if err != nil {
  173. fmt.Println("error in node address assignment!")
  174. return err
  175. }
  176. if node.Network == networkName {
  177. ipaddr, iperr := UniqueAddress(networkName)
  178. if iperr != nil {
  179. fmt.Println("error in node address assignment!")
  180. return iperr
  181. }
  182. node.Address = ipaddr
  183. data, err := json.Marshal(&node)
  184. if err != nil {
  185. return err
  186. }
  187. node.SetID()
  188. database.Insert(node.ID, string(data), database.NODES_TABLE_NAME)
  189. }
  190. }
  191. return nil
  192. }
  193. func NetworkNodesUpdateAction(networkName string, action string) error {
  194. collections, err := database.FetchRecords(database.NODES_TABLE_NAME)
  195. if err != nil {
  196. if database.IsEmptyRecord(err) {
  197. return nil
  198. }
  199. return err
  200. }
  201. for _, value := range collections {
  202. var node models.Node
  203. err := json.Unmarshal([]byte(value), &node)
  204. if err != nil {
  205. fmt.Println("error in node address assignment!")
  206. return err
  207. }
  208. if node.Network == networkName {
  209. node.Action = action
  210. data, err := json.Marshal(&node)
  211. if err != nil {
  212. return err
  213. }
  214. node.SetID()
  215. database.Insert(node.ID, string(data), database.NODES_TABLE_NAME)
  216. }
  217. }
  218. return nil
  219. }
  220. func NetworkNodesUpdatePullChanges(networkName string) error {
  221. collections, err := database.FetchRecords(database.NODES_TABLE_NAME)
  222. if err != nil {
  223. if database.IsEmptyRecord(err) {
  224. return nil
  225. }
  226. return err
  227. }
  228. for _, value := range collections {
  229. var node models.Node
  230. err := json.Unmarshal([]byte(value), &node)
  231. if err != nil {
  232. fmt.Println("error in node address assignment!")
  233. return err
  234. }
  235. if node.Network == networkName {
  236. node.PullChanges = "yes"
  237. data, err := json.Marshal(&node)
  238. if err != nil {
  239. return err
  240. }
  241. node.SetID()
  242. database.Insert(node.ID, string(data), database.NODES_TABLE_NAME)
  243. }
  244. }
  245. return nil
  246. }
  247. func UpdateNetworkLocalAddresses(networkName string) error {
  248. collection, err := database.FetchRecords(database.NODES_TABLE_NAME)
  249. if err != nil {
  250. return err
  251. }
  252. for _, value := range collection {
  253. var node models.Node
  254. err := json.Unmarshal([]byte(value), &node)
  255. if err != nil {
  256. fmt.Println("error in node address assignment!")
  257. return err
  258. }
  259. if node.Network == networkName {
  260. ipaddr, iperr := UniqueAddress(networkName)
  261. if iperr != nil {
  262. fmt.Println("error in node address assignment!")
  263. return iperr
  264. }
  265. node.Address = ipaddr
  266. newNodeData, err := json.Marshal(&node)
  267. if err != nil {
  268. fmt.Println("error in node address assignment!")
  269. return err
  270. }
  271. node.SetID()
  272. database.Insert(node.ID, string(newNodeData), database.NODES_TABLE_NAME)
  273. }
  274. }
  275. return nil
  276. }
  277. func IsNetworkDisplayNameUnique(name string) (bool, error) {
  278. isunique := true
  279. dbs, err := models.GetNetworks()
  280. if err != nil {
  281. return database.IsEmptyRecord(err), err
  282. }
  283. for i := 0; i < len(dbs); i++ {
  284. if name == dbs[i].DisplayName {
  285. isunique = false
  286. }
  287. }
  288. return isunique, nil
  289. }
  290. func IsMacAddressUnique(macaddress string, networkName string) (bool, error) {
  291. _, err := database.FetchRecord(database.NODES_TABLE_NAME, macaddress+"###"+networkName)
  292. if err != nil {
  293. return database.IsEmptyRecord(err), err
  294. }
  295. return true, nil
  296. }
  297. func GetNetworkNodeCount(networkName string) (int, error) {
  298. collection, err := database.FetchRecords(database.NODES_TABLE_NAME)
  299. count := 0
  300. if err != nil && !database.IsEmptyRecord(err) {
  301. return count, err
  302. }
  303. for _, value := range collection {
  304. var node models.Node
  305. if err = json.Unmarshal([]byte(value), &node); err != nil {
  306. return count, err
  307. } else {
  308. if node.Network == networkName {
  309. count++
  310. }
  311. }
  312. }
  313. return count, nil
  314. }
  315. //Checks to see if access key is valid
  316. //Does so by checking against all keys and seeing if any have the same value
  317. //may want to hash values before comparing...consider this
  318. //TODO: No error handling!!!!
  319. func IsKeyValid(networkname string, keyvalue string) bool {
  320. network, _ := GetParentNetwork(networkname)
  321. var key models.AccessKey
  322. foundkey := false
  323. isvalid := false
  324. for i := len(network.AccessKeys) - 1; i >= 0; i-- {
  325. currentkey := network.AccessKeys[i]
  326. if currentkey.Value == keyvalue {
  327. key = currentkey
  328. foundkey = true
  329. }
  330. }
  331. if foundkey {
  332. if key.Uses > 0 {
  333. isvalid = true
  334. }
  335. }
  336. return isvalid
  337. }
  338. func IsKeyValidGlobal(keyvalue string) bool {
  339. networks, _ := models.GetNetworks()
  340. var key models.AccessKey
  341. foundkey := false
  342. isvalid := false
  343. for _, network := range networks {
  344. for i := len(network.AccessKeys) - 1; i >= 0; i-- {
  345. currentkey := network.AccessKeys[i]
  346. if currentkey.Value == keyvalue {
  347. key = currentkey
  348. foundkey = true
  349. break
  350. }
  351. }
  352. if foundkey {
  353. break
  354. }
  355. }
  356. if foundkey {
  357. if key.Uses > 0 {
  358. isvalid = true
  359. }
  360. }
  361. return isvalid
  362. }
  363. //TODO: Contains a fatal error return. Need to change
  364. //This just gets a network object from a network name
  365. //Should probably just be GetNetwork. kind of a dumb name.
  366. //Used in contexts where it's not the Parent network.
  367. func GetParentNetwork(networkname string) (models.Network, error) {
  368. var network models.Network
  369. networkData, err := database.FetchRecord(database.NETWORKS_TABLE_NAME, networkname)
  370. if err != nil {
  371. return network, err
  372. }
  373. if err = json.Unmarshal([]byte(networkData), &network); err != nil {
  374. return models.Network{}, err
  375. }
  376. return network, nil
  377. }
  378. func IsIpNet(host string) bool {
  379. return net.ParseIP(host) != nil
  380. }
  381. //Similar to above but checks if Cidr range is valid
  382. //At least this guy's got some print statements
  383. //still not good error handling
  384. func IsIpCIDR(host string) bool {
  385. ip, ipnet, err := net.ParseCIDR(host)
  386. if err != nil {
  387. fmt.Println(err)
  388. fmt.Println("Address Range is not valid!")
  389. return false
  390. }
  391. return ip != nil && ipnet != nil
  392. }
  393. //This is used to validate public keys (make sure they're base64 encoded like all public keys should be).
  394. func IsBase64(s string) bool {
  395. _, err := base64.StdEncoding.DecodeString(s)
  396. return err == nil
  397. }
  398. //This checks to make sure a network name is valid.
  399. //Switch to REGEX?
  400. func NameInNetworkCharSet(name string) bool {
  401. charset := "abcdefghijklmnopqrstuvwxyz1234567890-_."
  402. for _, char := range name {
  403. if !strings.Contains(charset, strings.ToLower(string(char))) {
  404. return false
  405. }
  406. }
  407. return true
  408. }
  409. func NameInDNSCharSet(name string) bool {
  410. charset := "abcdefghijklmnopqrstuvwxyz1234567890-."
  411. for _, char := range name {
  412. if !strings.Contains(charset, strings.ToLower(string(char))) {
  413. return false
  414. }
  415. }
  416. return true
  417. }
  418. func NameInNodeCharSet(name string) bool {
  419. charset := "abcdefghijklmnopqrstuvwxyz1234567890-"
  420. for _, char := range name {
  421. if !strings.Contains(charset, strings.ToLower(string(char))) {
  422. return false
  423. }
  424. }
  425. return true
  426. }
  427. //This returns a node based on its mac address.
  428. //The mac address acts as the Unique ID for nodes.
  429. //Is this a dumb thing to do? I thought it was cool but maybe it's dumb.
  430. //It doesn't really provide a tangible benefit over a random ID
  431. func GetNodeByMacAddress(network string, macaddress string) (models.Node, error) {
  432. var node models.Node
  433. key, err := GetRecordKey(macaddress, network)
  434. if err != nil {
  435. return node, err
  436. }
  437. record, err := database.FetchRecord(database.NODES_TABLE_NAME, key)
  438. if err != nil {
  439. return models.Node{}, err
  440. }
  441. if err = json.Unmarshal([]byte(record), &node); err != nil {
  442. return models.Node{}, err
  443. }
  444. return node, nil
  445. }
  446. func DeleteAllIntClients() error {
  447. err := database.DeleteAllRecords(database.INT_CLIENTS_TABLE_NAME)
  448. if err != nil {
  449. return err
  450. }
  451. return nil
  452. }
  453. func GetAllIntClients() ([]models.IntClient, error) {
  454. var clients []models.IntClient
  455. collection, err := database.FetchRecords(database.INT_CLIENTS_TABLE_NAME)
  456. if err != nil {
  457. return clients, err
  458. }
  459. for _, value := range collection {
  460. var client models.IntClient
  461. err := json.Unmarshal([]byte(value), &client)
  462. if err != nil {
  463. return []models.IntClient{}, err
  464. }
  465. // add node to our array
  466. clients = append(clients, client)
  467. }
  468. return clients, nil
  469. }
  470. func GetAllExtClients() ([]models.ExtClient, error) {
  471. var extclients []models.ExtClient
  472. collection, err := database.FetchRecords(database.EXT_CLIENT_TABLE_NAME)
  473. if err != nil {
  474. return extclients, err
  475. }
  476. for _, value := range collection {
  477. var extclient models.ExtClient
  478. err := json.Unmarshal([]byte(value), &extclient)
  479. if err != nil {
  480. return []models.ExtClient{}, err
  481. }
  482. // add node to our array
  483. extclients = append(extclients, extclient)
  484. }
  485. return extclients, nil
  486. }
  487. //This returns a unique address for a node to use
  488. //it iterates through the list of IP's in the subnet
  489. //and checks against all nodes to see if it's taken, until it finds one.
  490. //TODO: We do not handle a case where we run out of addresses.
  491. //We will need to handle that eventually
  492. func UniqueAddress(networkName string) (string, error) {
  493. var network models.Network
  494. network, err := GetParentNetwork(networkName)
  495. if err != nil {
  496. fmt.Println("UniqueAddress encountered an error")
  497. return "666", err
  498. }
  499. offset := true
  500. ip, ipnet, err := net.ParseCIDR(network.AddressRange)
  501. if err != nil {
  502. fmt.Println("UniqueAddress encountered an error")
  503. return "666", err
  504. }
  505. for ip := ip.Mask(ipnet.Mask); ipnet.Contains(ip); Inc(ip) {
  506. if offset {
  507. offset = false
  508. continue
  509. }
  510. if networkName == "comms" {
  511. if IsIPUnique(networkName, ip.String(), database.INT_CLIENTS_TABLE_NAME, false) {
  512. return ip.String(), err
  513. }
  514. } else {
  515. if IsIPUnique(networkName, ip.String(), database.NODES_TABLE_NAME, false) && IsIPUnique(networkName, ip.String(), database.EXT_CLIENT_TABLE_NAME, false) {
  516. return ip.String(), err
  517. }
  518. }
  519. }
  520. //TODO
  521. err1 := errors.New("ERROR: No unique addresses available. Check network subnet.")
  522. return "W1R3: NO UNIQUE ADDRESSES AVAILABLE", err1
  523. }
  524. func UniqueAddress6(networkName string) (string, error) {
  525. var network models.Network
  526. network, err := GetParentNetwork(networkName)
  527. if err != nil {
  528. fmt.Println("Network Not Found")
  529. return "", err
  530. }
  531. if network.IsDualStack == "no" {
  532. if networkName != "comms" {
  533. return "", nil
  534. }
  535. }
  536. offset := true
  537. ip, ipnet, err := net.ParseCIDR(network.AddressRange6)
  538. if err != nil {
  539. fmt.Println("UniqueAddress6 encountered an error")
  540. return "666", err
  541. }
  542. for ip := ip.Mask(ipnet.Mask); ipnet.Contains(ip); Inc(ip) {
  543. if offset {
  544. offset = false
  545. continue
  546. }
  547. if networkName == "comms" {
  548. if IsIPUnique(networkName, ip.String(), database.INT_CLIENTS_TABLE_NAME, true) {
  549. return ip.String(), err
  550. }
  551. } else {
  552. if IsIPUnique(networkName, ip.String(), database.NODES_TABLE_NAME, true) {
  553. return ip.String(), err
  554. }
  555. }
  556. }
  557. //TODO
  558. err1 := errors.New("ERROR: No unique addresses available. Check network subnet.")
  559. return "W1R3: NO UNIQUE ADDRESSES AVAILABLE", err1
  560. }
  561. //generate an access key value
  562. func GenKey() string {
  563. var seededRand *rand.Rand = rand.New(
  564. rand.NewSource(time.Now().UnixNano()))
  565. length := 16
  566. charset := "abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
  567. b := make([]byte, length)
  568. for i := range b {
  569. b[i] = charset[seededRand.Intn(len(charset))]
  570. }
  571. return string(b)
  572. }
  573. //generate a key value
  574. //we should probably just have 1 random string generator
  575. //that can be used across all functions
  576. //have a "base string" a "length" and a "charset"
  577. func GenKeyName() string {
  578. var seededRand *rand.Rand = rand.New(
  579. rand.NewSource(time.Now().UnixNano()))
  580. length := 5
  581. charset := "abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
  582. b := make([]byte, length)
  583. for i := range b {
  584. b[i] = charset[seededRand.Intn(len(charset))]
  585. }
  586. return "key" + string(b)
  587. }
  588. func IsIPUnique(network string, ip string, tableName string, isIpv6 bool) bool {
  589. isunique := true
  590. collection, err := database.FetchRecords(tableName)
  591. if err != nil {
  592. return isunique
  593. }
  594. for _, value := range collection { // filter
  595. var node models.Node
  596. if err = json.Unmarshal([]byte(value), &node); err != nil {
  597. continue
  598. }
  599. if isIpv6 {
  600. if node.Address6 == ip && node.Network == network {
  601. return false
  602. }
  603. } else {
  604. if node.Address == ip && node.Network == network {
  605. return false
  606. }
  607. }
  608. }
  609. return isunique
  610. }
  611. //called once key has been used by createNode
  612. //reduces value by one and deletes if necessary
  613. func DecrimentKey(networkName string, keyvalue string) {
  614. var network models.Network
  615. network, err := GetParentNetwork(networkName)
  616. if err != nil {
  617. return
  618. }
  619. for i := len(network.AccessKeys) - 1; i >= 0; i-- {
  620. currentkey := network.AccessKeys[i]
  621. if currentkey.Value == keyvalue {
  622. network.AccessKeys[i].Uses--
  623. if network.AccessKeys[i].Uses < 1 {
  624. network.AccessKeys = append(network.AccessKeys[:i],
  625. network.AccessKeys[i+1:]...)
  626. break
  627. }
  628. }
  629. }
  630. if newNetworkData, err := json.Marshal(&network); err != nil {
  631. PrintUserLog("netmaker", "failed to decrement key", 2)
  632. return
  633. } else {
  634. database.Insert(network.NetID, string(newNetworkData), database.NETWORKS_TABLE_NAME)
  635. }
  636. }
  637. //takes the logic from controllers.deleteKey
  638. func DeleteKey(network models.Network, i int) {
  639. network.AccessKeys = append(network.AccessKeys[:i],
  640. network.AccessKeys[i+1:]...)
  641. if networkData, err := json.Marshal(&network); err != nil {
  642. return
  643. } else {
  644. database.Insert(network.NetID, string(networkData), database.NETWORKS_TABLE_NAME)
  645. }
  646. }
  647. //increments an IP over the previous
  648. func Inc(ip net.IP) {
  649. for j := len(ip) - 1; j >= 0; j-- {
  650. ip[j]++
  651. if ip[j] > 0 {
  652. break
  653. }
  654. }
  655. }