X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=genrules.py;h=4468c1e00e52d58fb12c9d4769ae12c95c7d2704;hb=d4d0eb34912fd66bf9eb73d98ed57fd3def3336a;hp=d372806a8e8c99a6b9fed67158cbf6e04e0406ba;hpb=94ae7afe2f87074c7353e247275fe33f7f774bd1;p=flowspec-xdp diff --git a/genrules.py b/genrules.py index d372806..4468c1e 100755 --- a/genrules.py +++ b/genrules.py @@ -3,25 +3,27 @@ import sys import ipaddress from enum import Enum +import argparse + IP_PROTO_ICMP = 1 IP_PROTO_ICMPV6 = 58 IP_PROTO_TCP = 6 IP_PROTO_UDP = 17 -if len(sys.argv) > 2 and sys.argv[2].startswith("parse_ihl"): - PARSE_IHL = True -else: - PARSE_IHL = False - class ASTAction(Enum): - OR = 1, - AND = 2, - NOT = 3, - EXPR = 4 + OR = 1 + AND = 2 + NOT = 3 + FALSE = 4 + TRUE = 5 + EXPR = 6 class ASTNode: def __init__(self, action, left, right=None): self.action = action + if action == ASTAction.FALSE or action == ASTAction.TRUE: + assert left is None and right is None + return self.left = left if right is None: assert action == ASTAction.EXPR or action == ASTAction.NOT @@ -35,23 +37,32 @@ class ASTNode: return "(" + self.left.write(expr_param, expr_param2) + ") && (" + self.right.write(expr_param, expr_param2) + ")" if self.action == ASTAction.NOT: return "!(" + self.left.write(expr_param, expr_param2) + ")" + if self.action == ASTAction.FALSE: + return "0" + if self.action == ASTAction.TRUE: + return "1" if self.action == ASTAction.EXPR: return self.left.write(expr_param, expr_param2) def parse_ast(expr, parse_expr): expr = expr.strip() - and_split = expr.split("&&", 1) + comma_split = expr.split(",", 1) or_split = expr.split("||", 1) - if len(and_split) > 1 and not "||" in and_split[0]: - return ASTNode(ASTAction.AND, parse_ast(and_split[0], parse_expr), parse_ast(and_split[1], parse_expr)) + if len(comma_split) > 1 and not "||" in comma_split[0]: + return ASTNode(ASTAction.OR, parse_ast(comma_split[0], parse_expr), parse_ast(comma_split[1], parse_expr)) if len(or_split) > 1: - assert not "&&" in or_split[0] + assert not "," in or_split[0] return ASTNode(ASTAction.OR, parse_ast(or_split[0], parse_expr), parse_ast(or_split[1], parse_expr)) - comma_split = expr.split(",", 1) - if len(comma_split) > 1: - return ASTNode(ASTAction.OR, parse_ast(comma_split[0], parse_expr), parse_ast(comma_split[1], parse_expr)) + and_split = expr.split("&&", 1) + if len(and_split) > 1: + return ASTNode(ASTAction.AND, parse_ast(and_split[0], parse_expr), parse_ast(and_split[1], parse_expr)) + + if expr.strip() == "true": + return ASTNode(ASTAction.TRUE, None) + if expr.strip() == "false": + return ASTNode(ASTAction.FALSE, None) if expr.startswith("!"): return ASTNode(ASTAction.NOT, parse_ast(expr[1:], parse_expr)) @@ -221,10 +232,10 @@ def dscp_to_rule(proto, rules): def port_to_rule(ty, rules): if ty == "port" : ast = parse_ast(rules, parse_numbers_expr) - return "if (tcp == NULL && udp == NULL) break;\nif (!( " + ast.write("sport", "dport") + " )) break;" + return "if (!ports_valid) break;\nif (!( " + ast.write("sport", "dport") + " )) break;" ast = parse_ast(rules, parse_numbers_expr) - return "if (tcp == NULL && udp == NULL) break;\nif (!( " + ast.write(ty) + " )) break;" + return "if (!ports_valid) break;\nif (!( " + ast.write(ty) + " )) break;" def tcp_flags_to_rule(rules): ast = parse_ast(rules, parse_bit_expr) @@ -239,17 +250,43 @@ def flow_label_to_rule(rules): if (!( {ast.write("((((uint32_t)(ip6->flow_lbl[0] & 0xf)) << 2*8) | (((uint32_t)ip6->flow_lbl[1]) << 1*8) | (uint32_t)ip6->flow_lbl[0])")} )) break;""" with open("rules.h", "w") as out: - if len(sys.argv) > 1 and sys.argv[1] == "parse_8021q": - out.write("#define PARSE_8021Q\n") - if len(sys.argv) > 1 and sys.argv[1].startswith("req_8021q="): - out.write("#define PARSE_8021Q\n") - out.write(f"#define REQ_8021Q {sys.argv[1][10:]}\n") - - - out.write("#define RULES \\\n") - - def write_rule(r): - out.write("\t\t" + r.replace("\n", " \\\n\t\t") + " \\\n") + parse = argparse.ArgumentParser() + parse.add_argument("--ihl", dest="ihl", required=True, choices=["drop-options","accept-options","parse-options"]) + parse.add_argument("--v6frag", dest="v6frag", required=True, choices=["drop-frags","ignore","parse-frags","ignore-parse-if-rule"]) + parse.add_argument("--8021q", dest="vlan", required=True, choices=["drop-vlan","accept-vlan","parse-vlan"]) + parse.add_argument("--require-8021q", dest="vlan_tag") + args = parse.parse_args(sys.argv[1:]) + + if args.ihl == "drop-options": + out.write("#define PARSE_IHL XDP_DROP\n") + elif args.ihl == "accept-options": + out.write("#define PARSE_IHL XDP_PASS\n") + elif args.ihl == "parse-options": + out.write("#define PARSE_IHL PARSE\n") + + if args.v6frag == "drop-frags": + out.write("#define PARSE_V6_FRAG XDP_DROP\n") + elif args.v6frag == "ignore": + pass + elif args.v6frag == "parse-frags": + out.write("#define PARSE_V6_FRAG PARSE\n") + + if args.vlan == "drop-vlan": + out.write("#define PARSE_8021Q XDP_DROP\n") + elif args.vlan == "accept-vlan": + out.write("#define PARSE_8021Q XDP_PASS\n") + elif args.vlan == "parse-vlan": + out.write("#define PARSE_8021Q PARSE\n") + + if args.vlan_tag is not None: + if args.vlan != "parse-vlan": + assert False + out.write("#define REQ_8021Q " + args.vlan_tag + "\n") + + rules6 = "" + rules4 = "" + use_v6_frags = False + rulecnt = 0 for line in sys.stdin.readlines(): t = line.split("{") @@ -257,15 +294,20 @@ with open("rules.h", "w") as out: continue if t[0].strip() == "flow4": proto = 4 - out.write("if (eth_proto == htons(ETH_P_IP)) { \\\n") - out.write("\tdo {\\\n") + rules4 += "\tdo {\\\n" elif t[0].strip() == "flow6": proto = 6 - out.write("if (eth_proto == htons(ETH_P_IPV6)) { \\\n") - out.write("\tdo {\\\n") + rules6 += "\tdo {\\\n" else: continue + def write_rule(r): + global rules4, rules6 + if proto == 6: + rules6 += "\t\t" + r.replace("\n", " \\\n\t\t") + " \\\n" + else: + rules4 += "\t\t" + r.replace("\n", " \\\n\t\t") + " \\\n" + rule = t[1].split("}")[0].strip() for step in rule.split(";"): if step.strip().startswith("src") or step.strip().startswith("dst"): @@ -298,12 +340,29 @@ with open("rules.h", "w") as out: elif step.strip().startswith("label"): write_rule(flow_label_to_rule(step.strip()[6:])) elif step.strip().startswith("fragment"): + if proto == 6: + use_v6_frags = True write_rule(fragment_to_rule(proto, step.strip()[9:])) elif step.strip() == "": pass else: assert False - out.write("\t\treturn XDP_DROP;\\\n") - out.write("\t} while(0);\\\n}\\\n") + write_rule(f"const uint32_t ruleidx = STATIC_RULE_CNT + {rulecnt};") + write_rule("DO_RETURN(ruleidx, XDP_DROP);") + if proto == 6: + rules6 += "\t} while(0);\\\n" + else: + rules4 += "\t} while(0);\\\n" + rulecnt += 1 out.write("\n") + out.write(f"#define RULECNT {rulecnt}\n") + if rules4 != "": + out.write("#define NEED_V4_PARSE\n") + out.write("#define RULES4 {\\\n" + rules4 + "}\n") + if rules6: + out.write("#define NEED_V6_PARSE\n") + out.write("#define RULES6 {\\\n" + rules6 + "}\n") + if args.v6frag == "ignore-parse-if-rule": + if use_v6_frags: + out.write("#define PARSE_V6_FRAG PARSE\n")