#!/usr/bin/env python3
"""Does the PSP's TMR check validate the whole cmd_buf RANGE, or only its start address?

Pass 86 showed a cmd_buf inside the TMR is rejected (0xa). The classic failure is checking
only the start: a buffer that STARTS outside and EXTENDS into the trusted region would then be
accepted, and any TA output written into it would land in TMR -- a write primitive across the
security boundary.

Cases (each a fresh LOAD_TA):
  A start well below TMR, length small            -> expect accept  (control)
  B start below TMR, length straddling TMR start  -> accept would be the BUG
  C start inside TMR                              -> expect reject  (control, known 0xa)
  D start just below TMR end, length past the end -> accept is fine (leaving TMR)
  E start at TMR end exactly                      -> expect accept
"""
import glob, struct, sys, time
sys.path.insert(0,'/root/psp/hw')
from tinygrad import Device
import tinygrad.runtime.autogen.am.am as am
from ring_wrap import install
adev=Device["AMD"].iface.dev_impl; psp=adev.psp
submit=install(psp,adev)
def alloc(n):
    pa=adev.mm.palloc(n,align=0x1000,zero=True,boot=False); return pa,adev.paddr2mc(pa)
blob=open(glob.glob('/root/psp/contall/ta_42-0-0-6_1c874c3c*')[0],'rb').read()
tmr_mc = adev.paddr2mc(psp.tmr_paddr); tmr_end = tmr_mc + psp.tmr_size
print('TMR mc range: %#x .. %#x (size %#x)'%(tmr_mc,tmr_end,psp.tmr_size), flush=True)
def try_load(tag, cmd_mc, cmd_len):
    ap_,amc=alloc(0x80000)
    n=(len(blob)+3)&~3
    adev.vram.view(ap_,n)[:]=blob+b'\x00'*(n-len(blob)); adev.gmc.flush_hdp()
    c=am.struct_psp_gfx_cmd_resp(cmd_id=am.GFX_CMD_ID_LOAD_TA); t=c.cmd.cmd_load_ta
    t.app_phy_addr_lo,t.app_phy_addr_hi=amc&0xFFFFFFFF,amc>>32; t.app_len=len(blob)
    t.cmd_buf_phy_addr_lo,t.cmd_buf_phy_addr_hi=cmd_mc&0xFFFFFFFF,cmd_mc>>32
    t.cmd_buf_len=cmd_len
    t0=time.time()
    try: r=submit(c); st=r.resp.status&0xFFFFFFFF
    except Exception as e:
        try: st=int(str(e).strip().split()[-1])&0xFFFFFFFF
        except Exception: st=-1
    dt=time.time()-t0
    print('  %-46s addr=%#-12x len=%#-8x -> %#-10x %.1fs%s'%(tag,cmd_mc,cmd_len,st,dt,
          '  <<< HANG' if dt>5 else ''), flush=True)
    return st
cp,cmc=alloc(0x8000)
try_load('A control: normal buffer', cmc, 0x2000)
try_load('B start BELOW tmr, extends INTO tmr', tmr_mc-0x2000, 0x8000)
try_load('C control: start inside tmr', tmr_mc+0x1000, 0x1000)
try_load('D start below tmr end, extends past end', tmr_end-0x1000, 0x8000)
try_load('E start exactly at tmr end', tmr_end, 0x2000)