| 1 | /* |
| 2 | * Copyright (c) 1982, 1986, 1989 Regents of the University of California. |
| 3 | * All rights reserved. The Berkeley software License Agreement |
| 4 | * specifies the terms and conditions for redistribution. |
| 5 | * |
| 6 | * @(#)sys_process.c 7.14 (Berkeley) %G% |
| 7 | */ |
| 8 | |
| 9 | #define IPCREG |
| 10 | #include "param.h" |
| 11 | #include "user.h" |
| 12 | #include "proc.h" |
| 13 | #include "vnode.h" |
| 14 | #include "seg.h" |
| 15 | #include "buf.h" |
| 16 | #include "ptrace.h" |
| 17 | |
| 18 | #include "machine/reg.h" |
| 19 | #include "machine/psl.h" |
| 20 | #include "../vm/vm_page.h" |
| 21 | #include "../vm/vm_prot.h" |
| 22 | |
| 23 | /* |
| 24 | * Priority for tracing |
| 25 | */ |
| 26 | #define IPCPRI PZERO |
| 27 | |
| 28 | /* |
| 29 | * Tracing variables. |
| 30 | * Used to pass trace command from |
| 31 | * parent to child being traced. |
| 32 | * This data base cannot be |
| 33 | * shared and is locked |
| 34 | * per user. |
| 35 | */ |
| 36 | struct { |
| 37 | int ip_lock; |
| 38 | int ip_req; |
| 39 | int *ip_addr; |
| 40 | int ip_data; |
| 41 | } ipc; |
| 42 | |
| 43 | /* |
| 44 | * sys-trace system call. |
| 45 | */ |
| 46 | ptrace(curp, uap, retval) |
| 47 | struct proc *curp; |
| 48 | register struct args { |
| 49 | int req; |
| 50 | int pid; |
| 51 | int *addr; |
| 52 | int data; |
| 53 | } *uap; |
| 54 | int *retval; |
| 55 | { |
| 56 | register struct proc *p; |
| 57 | |
| 58 | if (uap->req <= 0) { |
| 59 | curp->p_flag |= STRC; |
| 60 | return (0); |
| 61 | } |
| 62 | p = pfind(uap->pid); |
| 63 | if (p == 0 || p->p_stat != SSTOP || p->p_ppid != curp->p_pid || |
| 64 | !(p->p_flag & STRC)) |
| 65 | return (ESRCH); |
| 66 | while (ipc.ip_lock) |
| 67 | sleep((caddr_t)&ipc, IPCPRI); |
| 68 | ipc.ip_lock = p->p_pid; |
| 69 | ipc.ip_data = uap->data; |
| 70 | ipc.ip_addr = uap->addr; |
| 71 | ipc.ip_req = uap->req; |
| 72 | p->p_flag &= ~SWTED; |
| 73 | while (ipc.ip_req > 0) { |
| 74 | if (p->p_stat==SSTOP) |
| 75 | setrun(p); |
| 76 | sleep((caddr_t)&ipc, IPCPRI); |
| 77 | } |
| 78 | *retval = ipc.ip_data; |
| 79 | ipc.ip_lock = 0; |
| 80 | wakeup((caddr_t)&ipc); |
| 81 | if (ipc.ip_req < 0) |
| 82 | return (EIO); |
| 83 | return (0); |
| 84 | } |
| 85 | |
| 86 | #define PHYSOFF(p, o) \ |
| 87 | ((physadr)(p)+((o)/sizeof(((physadr)0)->r[0]))) |
| 88 | |
| 89 | /* |
| 90 | * Code that the child process |
| 91 | * executes to implement the command |
| 92 | * of the parent process in tracing. |
| 93 | */ |
| 94 | procxmt(p) |
| 95 | register struct proc *p; |
| 96 | { |
| 97 | register int i, *poff; |
| 98 | |
| 99 | if (ipc.ip_lock != p->p_pid) |
| 100 | return (0); |
| 101 | p->p_slptime = 0; |
| 102 | i = ipc.ip_req; |
| 103 | ipc.ip_req = 0; |
| 104 | switch (i) { |
| 105 | |
| 106 | case PT_READ_I: /* read the child's text space */ |
| 107 | if (!useracc((caddr_t)ipc.ip_addr, 4, B_READ)) |
| 108 | goto error; |
| 109 | ipc.ip_data = fuiword((caddr_t)ipc.ip_addr); |
| 110 | break; |
| 111 | |
| 112 | case PT_READ_D: /* read the child's data space */ |
| 113 | if (!useracc((caddr_t)ipc.ip_addr, 4, B_READ)) |
| 114 | goto error; |
| 115 | ipc.ip_data = fuword((caddr_t)ipc.ip_addr); |
| 116 | break; |
| 117 | |
| 118 | case PT_READ_U: /* read the child's u. */ |
| 119 | #ifdef HPUXCOMPAT |
| 120 | if (u.u_pcb.pcb_flags & PCB_HPUXTRACE) |
| 121 | i = hpuxtobsduoff(ipc.ip_addr); |
| 122 | else |
| 123 | #endif |
| 124 | i = (int)ipc.ip_addr; |
| 125 | if (i<0 || i > ctob(UPAGES)-sizeof(int)) |
| 126 | goto error; |
| 127 | ipc.ip_data = *(int *)PHYSOFF(&u, i); |
| 128 | break; |
| 129 | |
| 130 | case PT_WRITE_I: /* write the child's text space */ |
| 131 | if ((i = suiword((caddr_t)ipc.ip_addr, ipc.ip_data)) < 0) { |
| 132 | vm_offset_t sa, ea; |
| 133 | int rv; |
| 134 | |
| 135 | sa = trunc_page((vm_offset_t)ipc.ip_addr); |
| 136 | ea = round_page((vm_offset_t)ipc.ip_addr+sizeof(int)-1); |
| 137 | rv = vm_map_protect(p->p_map, sa, ea, |
| 138 | VM_PROT_DEFAULT, FALSE); |
| 139 | if (rv == KERN_SUCCESS) { |
| 140 | i = suiword((caddr_t)ipc.ip_addr, ipc.ip_data); |
| 141 | (void) vm_map_protect(p->p_map, sa, ea, |
| 142 | VM_PROT_READ|VM_PROT_EXECUTE, FALSE); |
| 143 | } |
| 144 | } |
| 145 | if (i < 0) |
| 146 | goto error; |
| 147 | break; |
| 148 | |
| 149 | case PT_WRITE_D: /* write the child's data space */ |
| 150 | if (suword((caddr_t)ipc.ip_addr, 0) < 0) |
| 151 | goto error; |
| 152 | (void) suword((caddr_t)ipc.ip_addr, ipc.ip_data); |
| 153 | break; |
| 154 | |
| 155 | case PT_WRITE_U: /* write the child's u. */ |
| 156 | #ifdef HPUXCOMPAT |
| 157 | if (u.u_pcb.pcb_flags & PCB_HPUXTRACE) |
| 158 | i = hpuxtobsduoff(ipc.ip_addr); |
| 159 | else |
| 160 | #endif |
| 161 | i = (int)ipc.ip_addr; |
| 162 | poff = (int *)PHYSOFF(&u, i); |
| 163 | for (i=0; i<NIPCREG; i++) |
| 164 | if (poff == &u.u_ar0[ipcreg[i]]) |
| 165 | goto ok; |
| 166 | if (poff == &u.u_ar0[PS]) { |
| 167 | ipc.ip_data |= PSL_USERSET; |
| 168 | ipc.ip_data &= ~PSL_USERCLR; |
| 169 | #ifdef PSL_CM_CLR |
| 170 | if (ipc.ip_data & PSL_CM) |
| 171 | ipc.ip_data &= ~PSL_CM_CLR; |
| 172 | #endif |
| 173 | goto ok; |
| 174 | } |
| 175 | #if defined(hp300) |
| 176 | #ifdef FPCOPROC |
| 177 | if (poff >= (int *)u.u_pcb.pcb_fpregs.fpf_regs && |
| 178 | poff <= (int *)&u.u_pcb.pcb_fpregs.fpf_fpiar) |
| 179 | goto ok; |
| 180 | #endif |
| 181 | #endif |
| 182 | goto error; |
| 183 | |
| 184 | ok: |
| 185 | *poff = ipc.ip_data; |
| 186 | break; |
| 187 | |
| 188 | case PT_STEP: /* single step the child */ |
| 189 | case PT_CONTINUE: /* continue the child */ |
| 190 | if ((int)ipc.ip_addr != 1) |
| 191 | u.u_ar0[PC] = (int)ipc.ip_addr; |
| 192 | if ((unsigned)ipc.ip_data > NSIG) |
| 193 | goto error; |
| 194 | p->p_xstat = ipc.ip_data; /* see issig */ |
| 195 | if (i == PT_STEP) |
| 196 | u.u_ar0[PS] |= PSL_T; |
| 197 | wakeup((caddr_t)&ipc); |
| 198 | return (1); |
| 199 | |
| 200 | case PT_KILL: /* kill the child process */ |
| 201 | wakeup((caddr_t)&ipc); |
| 202 | exit(p, (int)p->p_xstat); |
| 203 | |
| 204 | default: |
| 205 | error: |
| 206 | ipc.ip_req = -1; |
| 207 | } |
| 208 | wakeup((caddr_t)&ipc); |
| 209 | return (0); |
| 210 | } |