nx_doc_ubscan_gate.nx source

1import "nx_gate_gn.nx" 2// nx_doc_ubscan_gate.nx -- liar-kill gate for the UB cast-then-index detector (the recycler's CONVERT of the 3// undefined-behavior critique). MUST-FLAG: the dangerous inline `(EXPR as *T)[i]` (incl. inside a call). MUST-NOT- 4// FLAG: the SAFE bind-then-index (`let p = ... as *T; p[i]`), a plain cast with no index, and a paren-index with no 5// cast. Grounding: the motivating critique artifact recyc_crit_ub.raw really exists. expect_exit: 0 6import "nx_syscalls.nx" 7import "nx_doc_ubscan.nx" 8import "nx_gate_verdict.nx" 9 10func gp(s: *u8) -> i64 { var n: i64=0; while s[n]!=(0 as u8){n=n+1} sys_write(1,s,n); return 0 } 11func slen(s: *u8) -> i64 { var n: i64=0; while s[n]!=(0 as u8){n=n+1} return n } 12func have_file(p: *u8) -> i64 { let fd: i64=sys_openat_rd(p); if fd<0 { return 0 } sys_close(fd); return 1 } 13 14func main() -> i64 { 15 gp("=== nx_doc_ubscan_gate: detect the LM-031 inline cast-then-index UB (recycled from the UB critique) ===\n" as *u8) 16 var pass: i64=0; var fail: i64=0 17 18 // KAT1 MUST-FLAG: the exact LM-031 dangerous form 19 let s1: *u8 = "func f() -> i64 { return (c[5] as *i64)[idx] }" as *u8 20 if ub_scan(s1, slen(s1)) >= 0 { pass=pass+1 } else { fail=fail+1; gp(" FAIL kat1-missed-castindex\n" as *u8) } 21 22 // KAT2 MUST-NOT-FLAG: the SAFE bind-then-index (the LM-031 fix) 23 let s2: *u8 = "func g() -> i64 { let p: *i64 = c[5] as *i64; return p[idx] }" as *u8 24 if ub_scan(s2, slen(s2)) < 0 { pass=pass+1 } else { fail=fail+1; gp(" FAIL kat2-flagged-safe-bind\n" as *u8) } 25 26 // KAT3 MUST-NOT-FLAG: a plain cast with NO index 27 let s3: *u8 = "func h() -> i64 { let x: *u8 = p as *u8; return 0 }" as *u8 28 if ub_scan(s3, slen(s3)) < 0 { pass=pass+1 } else { fail=fail+1; gp(" FAIL kat3-flagged-plain-cast\n" as *u8) } 29 30 // KAT4 MUST-NOT-FLAG: a parenthesized index with NO cast 31 let s4: *u8 = "func k() -> i64 { let v: i64 = (a + b)[i]; return v }" as *u8 32 if ub_scan(s4, slen(s4)) < 0 { pass=pass+1 } else { fail=fail+1; gp(" FAIL kat4-flagged-noncast-index\n" as *u8) } 33 34 // KAT5 MUST-FLAG: cast-then-index nested inside a call argument 35 let s5: *u8 = "func m() -> i64 { return foo((x as *i64)[0]) }" as *u8 36 if ub_scan(s5, slen(s5)) >= 0 { pass=pass+1 } else { fail=fail+1; gp(" FAIL kat5-missed-nested\n" as *u8) } 37 38 // KAT6 grounding: the motivating critique artifact exists (this hardening was recycled from a real fetched page) 39 if have_file("knowledge/fetched/recyc_crit_ub.raw" as *u8)==1 { pass=pass+1 } else { fail=fail+1; gp(" FAIL kat6-ungrounded (recyc_crit_ub.raw missing)\n" as *u8) } 40 41 gp("DOC-UBSCAN-GATE pass=" as *u8); gn(pass); gp(" fail=" as *u8); gn(fail) 42 // MIGRATED onto nx_gate_verdict by nx_gate_dry_apply (D001, minimal form): every check 43 // row above is untouched, so the PASS/FAIL vector cannot change; only the hand-rolled 44 // verdict emission is replaced by the ONE shared base class. Proven by nx_gate_migrate verify. 45 let ctr__dry: *i64 = gv_ctr() 46 ctr__dry[0] = pass 47 ctr__dry[1] = pass + fail 48 let rc__dry: i64 = gv_verdict("DOC-UBSCAN-GATE" as *u8, ctr__dry, "inline cast-then-index UB flagged incl. nested; safe bind-then-index/plain-cast/noncast-index NOT flagged; recycled from the UB critique)" as *u8) 49 sys_exit(rc__dry) 50 return rc__dry 51}