simple daemon implementation

jackhart · May 21, 2023 · 7e88572 · 7e88572
1 parent af68c80
commit 7e88572
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Showing 14 changed files with 405 additions and 175 deletions.
diff --git a/Taskfile.yml b/Taskfile.yml
@@ -29,7 +29,7 @@ tasks:
     desc: Run pytests.
     deps: [ install, setup-network ]
     cmds:
-      - sudo ip netns exec basic {{.USER_WORKING_DIR}}/venv/bin/python3 -m pytest {{.CLI_ARGS}}
+      - sudo ip netns exec basic {{.USER_WORKING_DIR}}/venv/bin/python3 -m pytest -s {{.CLI_ARGS}}
 
   setup-network:
     desc: Setup the network namespaces for testing.

diff --git a/commands b/commands
@@ -4,9 +4,11 @@ export PYTHONPATH=/home/jack/Documents/projects/pygmp:$PYTHONPATH
 source venv/bin/activate
 python3 pygmp interactive
 
+ip netns exec basic python3 -m pytest tests/test_simple.py
+
 ip netns exec basic python3 pygmp smcrouted
 ip netns exec basic ping -c 3 -W 1 -I a3 -t 2 239.0.0.4
-
+ip netns exec basic ip mroute
 Usage: add vif <index> <ttl threshold> <rate limit> <interface addr or index> <remote addr>
 add vif 0 1 0 10.0.0.1 0.0.0.0
 add vif 1 1 0 20.0.0.1 0.0.0.0

diff --git a/network-setup.sh b/network-setup.sh
@@ -45,6 +45,19 @@ summary () {
 basic () {
   printf "\nCreating basic network...\n"
   ip netns add basic
+
+  # setup veth pair for REST API access
+  ip link add veth0 type veth peer name veth1
+  ip link set veth1 netns basic
+  ip addr add 172.20.0.1/24 dev veth0
+  ip link set veth0 up
+  ip netns exec basic ip addr add 172.20.0.2/24 dev veth1
+  ip netns exec basic ip link set veth1 up
+
+  # setup iptables for veth pair
+  iptables -t nat -A PREROUTING -p tcp --dport 8080 -j DNAT --to-destination 172.20.0.2:8000
+  ip netns exec basic iptables -t nat -A POSTROUTING -p tcp --sport 8000 -j MASQUERADE
+
   ip netns exec basic ip link add a1 type dummy
   ip netns exec basic ip link set a1 up
   ip netns exec basic ip link set a1 multicast on
@@ -61,6 +74,8 @@ basic () {
   ip netns exec basic ip addr add 20.0.0.1/24 dev a2
   ip netns exec basic ip addr add 30.0.0.1/24 dev a3
 
+  ip netns exec basic ip link set lo up
+
   summary basic
 
 }
@@ -69,8 +84,10 @@ main () {
 
   # a basc network setup =============================================
   if [ "$OVERWRITE" == true ] && [ "$(ip netns list | grep -wc "basic")" -eq 1 ]; then
-    echo "Deleting existing basic namespace..."
+    echo "Deleting existing basic namespace and iptable rules..."
+    iptables -t nat -D PREROUTING -p tcp --dport 8080 -j DNAT --to-destination 172.20.0.2:8000
     ip netns delete basic
+    ip link del veth0
   fi
 
   [[ $(ip netns list | grep -wc "basic") -eq 0 ]] && {

diff --git a/pygmp/__main__.py b/pygmp/__main__.py
@@ -22,7 +22,11 @@
 #  SOFTWARE.
 
 import argparse
+
+import kernel
 from pygmp.daemons import interactive, simple
+from fastapi import FastAPI
+import uvicorn
 
 
 def build_args():
@@ -41,10 +45,9 @@ def build_args():
     return parser.parse_args()
 
 
-def main():
-    args = build_args()
-    args.daemon(args)
-
 
 if __name__ == "__main__":
-    main()
+    with kernel.igmp_socket() as sock:
+        args = build_args()
+        app = args.daemon(sock, args, FastAPI())
+        uvicorn.run(app, host="172.20.0.2", port=8000)
diff --git a/pygmp/daemons/config.py b/pygmp/daemons/config.py
@@ -27,13 +27,17 @@
 from pygmp import kernel, data
 
 
+_DEFAULT_SOURCE = ip_address("0.0.0.0")
+_MROUTE_PREFIX = "mroute_"
+
+
 @dataclass
 class MRoute:
-    # TODO - support from address
-    from_: data.Interface
+    """Represents a multicast route."""
+    from_: str
     group: IPv4Address
-    to: list[data.Interface]
-    source: IPv4Address = ip_address("0.0.0.0")
+    to: dict[str, int]
+    source: IPv4Address = _DEFAULT_SOURCE
 
 
 @dataclass
@@ -43,45 +47,45 @@ class Config:
 
 
 def load_config(file_name: str) -> Config:
-
     config = configparser.ConfigParser()
     config.read(file_name)
 
-    phyints =  _get_phyints(config)
-    mroutes = _get_mroutes(config, phyints)
+    # TODO - better config validation
+    phyints =  _parse_phyints(config)
+    mroutes = _parse_mroutes(config)
     return Config(phyint=phyints, mroute=mroutes)
 
 
-def _get_mroutes(config_parser: configparser.ConfigParser, phyints: list[data.Interface]) -> list[MRoute]:
-    pyints_dict = {p.name: p for p in phyints}
+def _parse_mroutes(config_parser: configparser.ConfigParser) -> list[MRoute]:
     mroutes = []
     for name in config_parser.sections():
-        if name.startswith("mroute_"):
-            ii = pyints_dict[config_parser.get(name, "from")]
-            oil = [pyints_dict[inf] for inf in _str_list(config_parser.get(name, "to"))]
-            group = _get_group_address(config_parser.get(name, "group"))
+        if name.startswith(_MROUTE_PREFIX):
+            outgoing_interface_dict = _parse_outgoing_map(config_parser.get(name, "to"))
+            group = _parse_group_address(config_parser.get(name, "group"))
             source = ip_address(config_parser.get(name, "source", fallback="0.0.0.0"))
-            mroutes.append(MRoute(from_=ii, group=group, to=oil, source=source))
-
+            mroutes.append(MRoute(from_=config_parser.get(name, "from"), group=group,
+                                  to=outgoing_interface_dict, source=source))
     return mroutes
 
 
-def _get_group_address(group_address: str) -> IPv4Address:
-    group = ip_address(group_address)
-    # TODO - prefix len
-    if not group.is_multicast:
-        raise ValueError(f"invalid group address {group_address}")
+def _parse_phyints(config_parser: configparser.ConfigParser):
+    """Parse physical interfaces from the configuration."""
+    current_interfaces = kernel.network_interfaces()
+    names = _str_to_list(config_parser.get("phyints", "names", fallback=""))
+    return [_get_interface(current_interfaces, name) for name in names]
 
-    return group
 
+def _parse_group_address(group_address: str) -> IPv4Address:
+    """Validate and convert group address to IPv4Address object."""
+    group = ip_address(group_address) # TODO - prefix len support
+    if not group.is_multicast:
+        raise ValueError(f"Invalid group address {group_address}")
 
-def _get_phyints(config_parser: configparser.ConfigParser):
-    current_interfaces = kernel.network_interfaces()
-    names = _str_list(config_parser.get("phyints", "names", fallback=""))
-    return [_get_interface(current_interfaces, name) for name in names]
+    return group
 
 
 def _get_interface(interfaces, name):
+    """Get interface by name and validate it."""
     try:
         interface = interfaces[name]
     except KeyError:
@@ -96,5 +100,21 @@ def _get_interface(interfaces, name):
     return interface
 
 
-def _str_list(str_list: str) -> list[str]:
-    return [s.strip() for s in str_list.split(',')]
+def _parse_outgoing_map(to: str) -> dict[str, int]:
+    return {inf: ttl for inf, ttl in
+            (_str_to_key_value(inf_raw) for inf_raw in _str_to_list(to))}
+
+
+def _str_to_key_value(str_pair: str, default_value=1) -> tuple[str, int]:
+    """Convert a key=value string pair to a tuple."""
+    parts = str_pair.split('=')
+    if not parts[0].strip():
+        raise ValueError(f"Invalid key: {str_pair}")
+
+    value = int(parts[1].strip()) if len(parts) > 1 and parts[1].strip().isdigit() else default_value
+    return parts[0].strip(), value
+
+
+def _str_to_list(str_list: str) -> list[str]:
+    return [s.strip() for s in str_list.split(',')]
+
diff --git a/pygmp/daemons/interactive.py b/pygmp/daemons/interactive.py
@@ -41,7 +41,7 @@
 _logger = get_logger(__name__)
 
 
-def main(args):
+def main(args, app):
 
     with kernel.igmp_socket() as sock:
         _clean(sock)