Serge Bazanski | 6abe4fa | 2020-10-03 00:18:34 +0200 | [diff] [blame] | 1 | # Declarative routing configuration. Usees BIRD2 underneath. |
| 2 | # |
| 3 | # The mapping from declarative configuration to BIRD is quite straightforward, |
| 4 | # however, we take a few liberties: |
| 5 | # - we introduce an 'originate' protocol for originating prefixes (using the |
| 6 | # static protocol). |
| 7 | # - routing tables in the configuration are referred to by a common name for |
| 8 | # IPv4 and IPv4 - while in BIRD, two tables are created (suffixed by '4' and |
| 9 | # '6', following the two default 'master4' and 'master6' tables). |
| 10 | |
| 11 | { config, lib, pkgs, ... }: |
| 12 | |
| 13 | with lib; |
| 14 | let |
| 15 | cfg = config.hscloud.routing; |
| 16 | |
Serge Bazanski | d9a6365 | 2020-10-16 19:07:41 +0200 | [diff] [blame] | 17 | staticType = af: let |
| 18 | v4 = af == "ipv4"; |
| 19 | v6 = af == "ipv6"; |
| 20 | pretty = if v4 then "IPv4" else "IPv6"; |
| 21 | in with types; mkOption { |
| 22 | type = attrsOf (submodule { |
| 23 | options = { |
| 24 | table = mkOption { |
| 25 | type = nullOr str; |
| 26 | description = "BIRD table to which session should be connected."; |
| 27 | }; |
| 28 | address = mkOption { |
| 29 | type = str; |
| 30 | description = "Address part of prefix to announce."; |
| 31 | }; |
| 32 | prefixLength = mkOption { |
| 33 | type = int; |
| 34 | description = "Prefix length to announce."; |
| 35 | }; |
| 36 | via = mkOption { |
| 37 | type = str; |
| 38 | description = "Target address for static route."; |
| 39 | }; |
| 40 | }; |
| 41 | }); |
| 42 | default = {}; |
| 43 | description = "${pretty} static routes to inject into a table."; |
| 44 | }; |
| 45 | |
| 46 | staticRender = af: n: v: let |
| 47 | name = "static_static_${af}_${n}"; |
| 48 | ip = if af == "ipv4" then "4" else "6"; |
| 49 | in '' |
| 50 | protocol static ${name} { |
| 51 | ${af} { |
| 52 | table ${v.table}${ip}; |
| 53 | import all; |
| 54 | export none; |
| 55 | }; |
| 56 | |
| 57 | route ${v.address}/${toString v.prefixLength} via ${v.via}; |
| 58 | } |
| 59 | ''; |
| 60 | |
Serge Bazanski | 6abe4fa | 2020-10-03 00:18:34 +0200 | [diff] [blame] | 61 | originateType = af: let |
| 62 | v4 = af == "ipv4"; |
| 63 | v6 = af == "ipv6"; |
| 64 | pretty = if v4 then "IPv4" else "IPv6"; |
| 65 | in with types; mkOption { |
| 66 | type = attrsOf (submodule { |
| 67 | options = { |
| 68 | table = mkOption { |
| 69 | type = nullOr str; |
| 70 | description = "BIRD table to which session should be connected."; |
| 71 | }; |
| 72 | address = mkOption { |
| 73 | type = str; |
| 74 | description = "Address part of prefix to announce."; |
| 75 | }; |
| 76 | prefixLength = mkOption { |
| 77 | type = int; |
| 78 | description = "Prefix length to announce."; |
| 79 | }; |
| 80 | }; |
| 81 | }); |
| 82 | default = {}; |
| 83 | description = "${pretty} prefixes to unconditionally inject into a table."; |
| 84 | }; |
| 85 | |
| 86 | originateRender = af: n: v: let |
| 87 | name = "static_originate_${af}_${n}"; |
| 88 | ip = if af == "ipv4" then "4" else "6"; |
| 89 | in '' |
| 90 | protocol static ${name} { |
| 91 | ${af} { |
| 92 | table ${v.table}${ip}; |
| 93 | import all; |
| 94 | export none; |
| 95 | }; |
| 96 | |
| 97 | route ${v.address}/${toString v.prefixLength} blackhole; |
| 98 | } |
| 99 | ''; |
| 100 | |
| 101 | ospfType = af: let |
| 102 | v4 = af == "ipv4"; |
| 103 | v6 = af == "ipv6"; |
| 104 | pretty = if v4 then "IPv4" else "IPv6"; |
| 105 | ospf = if v4 then "OSPFv2" else "OSPFv3"; |
| 106 | in with types; mkOption { |
| 107 | type = attrsOf (submodule { |
| 108 | options = { |
| 109 | table = mkOption { |
| 110 | type = nullOr str; |
| 111 | description = "BIRD table to which session should be connected."; |
| 112 | }; |
| 113 | filterIn = mkOption { |
| 114 | type = str; |
| 115 | default = "accept;"; |
| 116 | description = "BIRD filter definition for received routes."; |
| 117 | }; |
| 118 | filterOut = mkOption { |
| 119 | type = str; |
| 120 | default = "accept;"; |
| 121 | description = "BIRD filter definition for sent routes."; |
| 122 | }; |
| 123 | area = mkOption { |
| 124 | type = attrsOf (submodule { |
| 125 | options = { |
| 126 | interfaces = mkOption { |
| 127 | type = attrsOf (submodule { |
| 128 | options = { |
| 129 | cost = mkOption { |
| 130 | type = int; |
| 131 | default = 10; # 1Gbps |
| 132 | description = "Interface cost (10e9/iface_speed_in_bps)."; |
| 133 | }; |
| 134 | type = mkOption { |
| 135 | type = enum ["bcast" "nbma" "ptp" "ptmp"]; |
| 136 | description = "Interface type (dictates BIRD behaviour)."; |
| 137 | }; |
| 138 | stub = mkOption { |
| 139 | type = bool; |
| 140 | default = false; |
| 141 | description = "Interface is stub (do not HELLO)."; |
| 142 | }; |
| 143 | }; |
| 144 | }); |
| 145 | description = "Interface configuration"; |
| 146 | }; |
| 147 | }; |
| 148 | }); |
| 149 | description = "Area configuration"; |
| 150 | }; |
| 151 | }; |
| 152 | }); |
| 153 | default = {}; |
| 154 | description = "${ospf} configuration"; |
| 155 | }; |
| 156 | |
| 157 | ospfRender = af: n: v: let |
| 158 | v4 = af == "ipv4"; |
| 159 | v6 = af == "ipv6"; |
| 160 | ip = if v4 then "4" else "6"; |
| 161 | name = "ospf_${af}_${n}"; |
| 162 | |
| 163 | interfaces = mapAttrsToList (iface: ifaceConfig: '' |
| 164 | interface "${iface}" { |
| 165 | type ${ifaceConfig.type}; |
| 166 | cost ${toString ifaceConfig.cost}; |
| 167 | ${if ifaceConfig.stub then "stub yes;" else ""} |
| 168 | }; |
| 169 | ''); |
| 170 | areas = mapAttrsToList (area: areaConfig: '' |
| 171 | area ${area} { |
| 172 | ${concatStringsSep "\n" (interfaces areaConfig.interfaces)} |
| 173 | }; |
| 174 | '') v.area; |
| 175 | in '' |
| 176 | filter ${name}_in { |
| 177 | ${v.filterIn} |
| 178 | }; |
| 179 | filter ${name}_out { |
| 180 | ${v.filterOut} |
| 181 | }; |
| 182 | protocol ospf ${if v4 then "v2" else "v3"} ${name} { |
| 183 | ${af} { |
| 184 | table ${v.table}${ip}; |
| 185 | import filter ${name}_in; |
| 186 | export filter ${name}_out; |
| 187 | }; |
| 188 | ${concatStringsSep "\n" areas} |
| 189 | } |
| 190 | ''; |
| 191 | |
| 192 | pipeType = af: with types; mkOption { |
| 193 | type = attrsOf (submodule { |
| 194 | options = { |
| 195 | table = mkOption { |
| 196 | type = nullOr str; |
| 197 | description = "BIRD table to which session should be connected."; |
| 198 | }; |
| 199 | peerTable = mkOption { |
| 200 | type = nullOr str; |
| 201 | description = "BIRD 'remote' table to which session should be connected."; |
| 202 | }; |
| 203 | filterIn = mkOption { |
| 204 | type = str; |
| 205 | default = "accept"; |
| 206 | description = "BIRD filter definition for routes received from peerTable"; |
| 207 | }; |
| 208 | filterOut = mkOption { |
| 209 | type = str; |
| 210 | default = "reject;"; |
| 211 | description = "BIRD filter definition for routes sent to peerTable"; |
| 212 | }; |
| 213 | }; |
| 214 | }); |
| 215 | default = {}; |
| 216 | description = "${pretty} prefixes to pipe from one table to another."; |
| 217 | }; |
| 218 | |
| 219 | pipeRender = af: n: v: let |
| 220 | name = "pipe_${af}_${n}"; |
| 221 | v4 = af == "ipv4"; |
| 222 | v6 = af == "ipv6"; |
| 223 | ip = if v4 then "4" else "6"; |
| 224 | in '' |
| 225 | filter ${name}_in { |
| 226 | ${v.filterIn} |
| 227 | }; |
| 228 | filter ${name}_out { |
| 229 | ${v.filterOut} |
| 230 | }; |
| 231 | protocol pipe ${name} { |
| 232 | table ${v.table}${ip}; |
| 233 | peer table ${v.peerTable}${ip}; |
| 234 | import filter ${name}_in; |
| 235 | export filter ${name}_out; |
| 236 | } |
| 237 | ''; |
| 238 | |
| 239 | bgpSessionsType = af: let |
| 240 | v4 = af == "ipv4"; |
| 241 | v6 = af == "ipv6"; |
| 242 | pretty = if v4 then "IPv4" else "IPv6"; |
| 243 | in with types; mkOption { |
| 244 | type = attrsOf (submodule { |
| 245 | options = { |
| 246 | description = mkOption { |
| 247 | type = str; |
| 248 | description = "Session description (for BIRD)."; |
| 249 | }; |
| 250 | table = mkOption { |
| 251 | type = nullOr str; |
| 252 | description = "BIRD table to which session should be connected."; |
| 253 | }; |
| 254 | local = mkOption { |
| 255 | type = str; |
| 256 | description = "${pretty} address of this router."; |
| 257 | }; |
| 258 | asn = mkOption { |
| 259 | type = int; |
| 260 | description = "ASN of local router - will default to hscloud.routing.asn."; |
| 261 | default = cfg.asn; |
| 262 | }; |
| 263 | prepend = mkOption { |
| 264 | type = int; |
| 265 | default = 0; |
| 266 | description = "How many times to prepend this router's ASN on the link."; |
| 267 | }; |
| 268 | pref = mkOption { |
| 269 | type = int; |
| 270 | default = 100; |
| 271 | description = "Preference (BGP local_pref) for routes from this session."; |
| 272 | }; |
| 273 | direct = mkOption { |
| 274 | type = nullOr bool; |
| 275 | default = null; |
| 276 | }; |
| 277 | filterIn = mkOption { |
| 278 | type = str; |
| 279 | default = "accept;"; |
| 280 | description = "BIRD filter definition for received routes."; |
| 281 | }; |
| 282 | filterOut = mkOption { |
| 283 | type = str; |
| 284 | default = "accept;"; |
| 285 | description = "BIRD filter definition for sent routes."; |
| 286 | }; |
| 287 | neighbors = mkOption { |
| 288 | type = listOf (submodule { |
| 289 | options = { |
| 290 | address = mkOption { |
| 291 | type = str; |
| 292 | description = "${pretty} address of neighbor."; |
| 293 | }; |
| 294 | asn = mkOption { |
| 295 | type = int; |
| 296 | description = "ASN of neighbor."; |
| 297 | }; |
| 298 | password = mkOption { |
| 299 | type = nullOr str; |
| 300 | default = null; |
| 301 | description = "BGP TCP MD5 secret."; |
| 302 | }; |
| 303 | }; |
| 304 | }); |
| 305 | description = "BGP Neighbor configuration"; |
| 306 | }; |
| 307 | }; |
| 308 | }); |
| 309 | default = {}; |
| 310 | description = "BGP Sesions for ${pretty}"; |
| 311 | }; |
| 312 | |
| 313 | bgpSessionRender = af: n: v: let |
| 314 | name = "bgp_${af}_${n}"; |
| 315 | ip = if af == "ipv4" then "4" else "6"; |
| 316 | filters = '' |
| 317 | filter ${name}_in { |
| 318 | if bgp_path.len > 64 then reject; |
| 319 | bgp_local_pref = ${toString v.pref}; |
| 320 | ${v.filterIn} |
| 321 | } |
| 322 | |
| 323 | filter ${name}_out { |
| 324 | ${if v.prepend > 0 then |
| 325 | (concatStringsSep "\n" |
| 326 | (map (_: "bgp_path.prepend(${toString v.asn});") (range 0 (v.prepend - 1))) |
| 327 | ) |
| 328 | else ""} |
| 329 | ${v.filterOut} |
| 330 | } |
| 331 | ''; |
| 332 | peer = ix: peer: '' |
| 333 | protocol bgp ${name}_${toString ix} { |
| 334 | description "${v.description}"; |
| 335 | |
| 336 | ${af} { |
| 337 | table ${v.table}${ip}; |
| 338 | import filter ${name}_in; |
| 339 | export filter ${name}_out; |
| 340 | }; |
| 341 | |
| 342 | local ${v.local} as ${toString v.asn}; |
| 343 | neighbor ${peer.address} as ${toString peer.asn}; |
| 344 | ${if peer.password != null then "password \"${peer.password}\";" else ""} |
| 345 | ${if v.direct == true then "direct;" else ""} |
| 346 | } |
| 347 | ''; |
| 348 | in "${filters}\n${concatStringsSep "\n" (imap1 peer v.neighbors)}"; |
| 349 | |
| 350 | tablesFromProtoAF = |
| 351 | af: p: filter (el: el != null) ( |
| 352 | mapAttrsToList (_: v: "${af} table ${v.table}${if af == "ipv4" then "4" else "6"};") p); |
| 353 | tablesFromProto = p: (tablesFromProtoAF "ipv4" p.v4) ++ (tablesFromProtoAF "ipv6" p.v6); |
| 354 | tables = |
| 355 | unique ( |
| 356 | (tablesFromProto cfg.bgpSessions) ++ |
| 357 | (tablesFromProto cfg.originate) ++ |
| 358 | (tablesFromProto cfg.pipe) ++ |
| 359 | (tablesFromProto cfg.ospf) |
| 360 | # TODO(q3k): also slurp in peer tables from pipes. |
| 361 | ); |
| 362 | tablesRender = '' |
| 363 | ${concatStringsSep "\n" tables} |
| 364 | ''; |
| 365 | tablesProgram = mapAttrsToList (n: _: n) (filterAttrs (n: v: v.program == true) cfg.tables); |
| 366 | tableProgram = |
| 367 | if (length tablesProgram) != 1 then |
| 368 | (abort "exactly one table must be set to be programmed") |
| 369 | else |
| 370 | (head tablesProgram); |
| 371 | |
| 372 | in { |
| 373 | options.hscloud.routing = { |
| 374 | enable = mkEnableOption "declarative routing"; |
| 375 | routerID = mkOption { |
| 376 | type = types.str; |
| 377 | description = '' |
| 378 | Default Router ID for dynamic routing protocols, eg. IPv4 address from |
| 379 | loopback interface. |
| 380 | ''; |
| 381 | }; |
| 382 | asn = mkOption { |
| 383 | type = types.int; |
| 384 | description = "Default ASN for BGP."; |
| 385 | }; |
| 386 | extra = mkOption { |
| 387 | type = types.lines; |
| 388 | description = "Extra configuration lines."; |
| 389 | }; |
| 390 | bgpSessions = { |
| 391 | v4 = bgpSessionsType "ipv4"; |
| 392 | v6 = bgpSessionsType "ipv6"; |
| 393 | }; |
| 394 | originate = { |
| 395 | v4 = originateType "ipv4"; |
| 396 | v6 = originateType "ipv6"; |
| 397 | }; |
Serge Bazanski | d9a6365 | 2020-10-16 19:07:41 +0200 | [diff] [blame] | 398 | static = { |
| 399 | v4 = staticType "ipv4"; |
| 400 | v6 = staticType "ipv6"; |
| 401 | }; |
Serge Bazanski | 6abe4fa | 2020-10-03 00:18:34 +0200 | [diff] [blame] | 402 | pipe = { |
| 403 | v4 = pipeType "ipv4"; |
| 404 | v6 = pipeType "ipv6"; |
| 405 | }; |
| 406 | ospf = { |
| 407 | v4 = ospfType "ipv4"; |
| 408 | v6 = ospfType "ipv6"; |
| 409 | }; |
| 410 | tables = mkOption { |
| 411 | type = types.attrsOf (types.submodule { |
| 412 | options = { |
| 413 | program = mkOption { |
| 414 | type = types.bool; |
| 415 | default = false; |
| 416 | description = "This is the primary table programmed in to the kernel."; |
| 417 | }; |
| 418 | programSourceV4 = mkOption { |
| 419 | type = types.nullOr types.str; |
| 420 | default = null; |
| 421 | description = "If set, programmed routes will have source set to this address."; |
| 422 | }; |
| 423 | programSourceV6 = mkOption { |
| 424 | type = types.nullOr types.str; |
| 425 | default = null; |
| 426 | description = "If set, programmed routes will have source set to this address."; |
| 427 | }; |
| 428 | }; |
| 429 | }); |
| 430 | description = "Routing table configuration."; |
| 431 | }; |
| 432 | }; |
| 433 | |
| 434 | config = mkIf cfg.enable { |
| 435 | services.bird2.enable = true; |
| 436 | services.bird2.config = '' |
| 437 | log syslog all; |
| 438 | debug protocols { states, interfaces, events } |
| 439 | |
| 440 | router id ${cfg.routerID}; |
| 441 | |
| 442 | ${cfg.extra} |
| 443 | |
| 444 | ${tablesRender} |
| 445 | |
| 446 | protocol device { |
| 447 | scan time 10; |
| 448 | }; |
| 449 | |
| 450 | protocol kernel kernel_v4 { |
| 451 | scan time 60; |
| 452 | ipv4 { |
| 453 | table ${tableProgram}4; |
| 454 | import none; |
| 455 | export filter { |
| 456 | ${let src = cfg.tables."${tableProgram}".programSourceV4; in if src != null then '' |
| 457 | krt_prefsrc = ${src}; |
| 458 | '' else ""} |
| 459 | accept; |
| 460 | }; |
| 461 | }; |
| 462 | } |
| 463 | protocol kernel kernel_v6 { |
| 464 | scan time 60; |
| 465 | ipv6 { |
| 466 | table ${tableProgram}6; |
| 467 | import none; |
| 468 | export filter { |
| 469 | ${let src = cfg.tables."${tableProgram}".programSourceV6; in if src != null then '' |
| 470 | krt_prefsrc = ${src}; |
| 471 | '' else ""} |
| 472 | accept; |
| 473 | }; |
| 474 | }; |
| 475 | }; |
| 476 | |
| 477 | ${concatStringsSep "\n" (mapAttrsToList (bgpSessionRender "ipv4") cfg.bgpSessions.v4)} |
| 478 | ${concatStringsSep "\n" (mapAttrsToList (bgpSessionRender "ipv6") cfg.bgpSessions.v6)} |
| 479 | ${concatStringsSep "\n" (mapAttrsToList (originateRender "ipv4") cfg.originate.v4)} |
| 480 | ${concatStringsSep "\n" (mapAttrsToList (originateRender "ipv6") cfg.originate.v6)} |
Serge Bazanski | d9a6365 | 2020-10-16 19:07:41 +0200 | [diff] [blame] | 481 | ${concatStringsSep "\n" (mapAttrsToList (staticRender "ipv4") cfg.static.v4)} |
| 482 | ${concatStringsSep "\n" (mapAttrsToList (staticRender "ipv6") cfg.static.v6)} |
Serge Bazanski | 6abe4fa | 2020-10-03 00:18:34 +0200 | [diff] [blame] | 483 | ${concatStringsSep "\n" (mapAttrsToList (pipeRender "ipv4") cfg.pipe.v4)} |
| 484 | ${concatStringsSep "\n" (mapAttrsToList (pipeRender "ipv6") cfg.pipe.v6)} |
| 485 | ${concatStringsSep "\n" (mapAttrsToList (ospfRender "ipv4") cfg.ospf.v4)} |
| 486 | ${concatStringsSep "\n" (mapAttrsToList (ospfRender "ipv6") cfg.ospf.v6)} |
| 487 | |
| 488 | ''; |
| 489 | }; |
| 490 | } |