code wiki / _hdl_build / nx_apistack_audit_gate.nx
`nx_apistack_audit_gate.nx` source

1import "nx_gate_gn.nx"
2// nx_apistack_audit_gate.nx -- hermetic gate for CAP-API-AUDIT (tamper-evident hash-chained audit log). Proves
3// records chain, the whole chain verifies intact, last-hash tracks the head, and -- the point -- altering ANY past
4// record is DETECTED. Sovereign: nx_syscalls + nx_apistack_audit. expect_exit: 0
5import "nx_syscalls.nx"
6import "nx_apistack_audit.nx"
7
8func gp(s: *u8) -> i64 { var n: i64=0; while s[n]!=(0 as u8){n=n+1} sys_write(1,s,n); return 0 }
9func g_app(buf: *u8, off: i64, s: *u8) -> i64 { var i: i64=0; while s[i]!=(0 as u8){buf[off+i]=s[i];i=i+1} return off+i }
10func g_pl(buf: *u8, a: *u8, b: *u8, c: *u8) -> i64 { var o: i64 = g_app(buf,0,a); buf[o]=9 as u8; o=o+1; o=g_app(buf,o,b); buf[o]=9 as u8; o=o+1; o=g_app(buf,o,c); return o }
11
12func main(argc: i64, argv: *i64) -> i64 {
13    gp("=== nx_apistack_audit_gate (tamper-evident hash-chained audit log) ===\n" as *u8)
14    let L: *u8 = "/tmp/au_log.tsv" as *u8
15    let fd0: i64 = sys_openat_wr(L, 0x1a4); if fd0 >= 0 { sys_close(fd0) }   // fresh
16    var pass: i64 = 0; var fail: i64 = 0
17
18    let p1: *u8 = sys_mmap(64); let p1n: i64 = g_pl(p1, "DEPLOY" as *u8, "elderwesto" as *u8, "rc=0" as *u8)
19    let p2: *u8 = sys_mmap(64); let p2n: i64 = g_pl(p2, "RESTART" as *u8, "elderwesto" as *u8, "rc=0" as *u8)
20    let p3: *u8 = sys_mmap(64); let p3n: i64 = g_pl(p3, "RECONCILE" as *u8, "elderwesto" as *u8, "ok" as *u8)
21    let h1: i64 = au_append(L, p1, p1n)
22    let h2: i64 = au_append(L, p2, p2n)
23    let h3: i64 = au_append(L, p3, p3n)
24
25    // T1 records chain (distinct hashes, each folds the prior)
26    if h1 != h2 { if h2 != h3 { pass=pass+1; gp("  T1 records chain (distinct linked hashes) PASS\n" as *u8) } else { fail=fail+1; gp("  T1 FAIL h2==h3\n" as *u8) } } else { fail=fail+1; gp("  T1 FAIL h1==h2\n" as *u8) }
27
28    // T2 whole chain verifies intact
29    if au_verify(L) == 1 { pass=pass+1; gp("  T2 intact chain -> verify=1 PASS\n" as *u8) } else { fail=fail+1; gp("  T2 FAIL\n" as *u8) }
30
31    // T3 last-chain tracks the head
32    if au_last_chain(L) == h3 { pass=pass+1; gp("  T3 last-chain == head hash PASS\n" as *u8) } else { fail=fail+1; gp("  T3 FAIL\n" as *u8) }
33
34    // T4 TAMPER a past record -> detected
35    let buf: *u8 = sys_mmap(65536); let n: i64 = au_read_file(L, buf, 65536)
36    buf[17] = (buf[17] ^ 1) as u8                   // flip a bit inside record 1's payload
37    let fw: i64 = sys_openat_wr(L, 0x1a4); if fw >= 0 { sys_write(fw, buf, n); sys_close(fw) }
38    if au_verify(L) == 0 { pass=pass+1; gp("  T4 tampered past record -> DETECTED (verify=0) PASS\n" as *u8) } else { fail=fail+1; gp("  T4 FAIL tamper undetected\n" as *u8) }
39
40    gp("RESULT pass=" as *u8); gn(pass); gp(" fail=" as *u8); gn(fail)
41    if fail == 0 { gp(" verdict=GREEN\n" as *u8); sys_exit(0); return 0 }
42    gp(" verdict=RED\n" as *u8); sys_exit(1); return 1
43}
nx_apistack_audit_gate.nx source

`nx_apistack_audit_gate.nx` source
