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 7.16 (Berkeley) 03/17/91 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_pptr != curp || 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 #if defined(i386) 89 #undef PC 90 #undef SP 91 #undef PS 92 #undef R0 93 #undef R1 94 95 #define PC tEIP 96 #define SP tESP 97 #define PS tEFLAGS 98 #define R0 tEDX 99 #define R1 tECX 100 #endif 101 102 /* 103 * Code that the child process 104 * executes to implement the command 105 * of the parent process in tracing. 106 */ 107 procxmt(p) 108 register struct proc *p; 109 { 110 register int i, *poff; 111 112 if (ipc.ip_lock != p->p_pid) 113 return (0); 114 p->p_slptime = 0; 115 i = ipc.ip_req; 116 ipc.ip_req = 0; 117 switch (i) { 118 119 case PT_READ_I: /* read the child's text space */ 120 if (!useracc((caddr_t)ipc.ip_addr, 4, B_READ)) 121 goto error; 122 ipc.ip_data = fuiword((caddr_t)ipc.ip_addr); 123 break; 124 125 case PT_READ_D: /* read the child's data space */ 126 if (!useracc((caddr_t)ipc.ip_addr, 4, B_READ)) 127 goto error; 128 ipc.ip_data = fuword((caddr_t)ipc.ip_addr); 129 break; 130 131 case PT_READ_U: /* read the child's u. */ 132 #ifdef HPUXCOMPAT 133 if (u.u_pcb.pcb_flags & PCB_HPUXTRACE) 134 i = hpuxtobsduoff(ipc.ip_addr); 135 else 136 #endif 137 i = (int)ipc.ip_addr; 138 if (i<0 || i > ctob(UPAGES)-sizeof(int)) 139 goto error; 140 ipc.ip_data = *(int *)PHYSOFF(&u, i); 141 break; 142 143 case PT_WRITE_I: /* write the child's text space */ 144 if ((i = suiword((caddr_t)ipc.ip_addr, ipc.ip_data)) < 0) { 145 vm_offset_t sa, ea; 146 int rv; 147 148 sa = trunc_page((vm_offset_t)ipc.ip_addr); 149 ea = round_page((vm_offset_t)ipc.ip_addr+sizeof(int)-1); 150 rv = vm_map_protect(&p->p_vmspace->vm_map, sa, ea, 151 VM_PROT_DEFAULT, FALSE); 152 if (rv == KERN_SUCCESS) { 153 i = suiword((caddr_t)ipc.ip_addr, ipc.ip_data); 154 (void) vm_map_protect(&p->p_vmspace->vm_map, 155 sa, ea, VM_PROT_READ|VM_PROT_EXECUTE, 156 FALSE); 157 } 158 } 159 if (i < 0) 160 goto error; 161 break; 162 163 case PT_WRITE_D: /* write the child's data space */ 164 if (suword((caddr_t)ipc.ip_addr, 0) < 0) 165 goto error; 166 (void) suword((caddr_t)ipc.ip_addr, ipc.ip_data); 167 break; 168 169 case PT_WRITE_U: /* write the child's u. */ 170 #ifdef HPUXCOMPAT 171 if (u.u_pcb.pcb_flags & PCB_HPUXTRACE) 172 i = hpuxtobsduoff(ipc.ip_addr); 173 else 174 #endif 175 i = (int)ipc.ip_addr; 176 poff = (int *)PHYSOFF(&u, i); 177 for (i=0; i<NIPCREG; i++) 178 if (poff == &p->p_regs[ipcreg[i]]) 179 goto ok; 180 if (poff == &p->p_regs[PS]) { 181 ipc.ip_data |= PSL_USERSET; 182 ipc.ip_data &= ~PSL_USERCLR; 183 #ifdef PSL_CM_CLR 184 if (ipc.ip_data & PSL_CM) 185 ipc.ip_data &= ~PSL_CM_CLR; 186 #endif 187 goto ok; 188 } 189 #if defined(hp300) 190 #ifdef FPCOPROC 191 if (poff >= (int *)u.u_pcb.pcb_fpregs.fpf_regs && 192 poff <= (int *)&u.u_pcb.pcb_fpregs.fpf_fpiar) 193 goto ok; 194 #endif 195 #endif 196 goto error; 197 198 ok: 199 *poff = ipc.ip_data; 200 break; 201 202 case PT_STEP: /* single step the child */ 203 case PT_CONTINUE: /* continue the child */ 204 if ((int)ipc.ip_addr != 1) 205 p->p_regs[PC] = (int)ipc.ip_addr; 206 if ((unsigned)ipc.ip_data > NSIG) 207 goto error; 208 p->p_xstat = ipc.ip_data; /* see issig */ 209 if (i == PT_STEP) 210 p->p_regs[PS] |= PSL_T; 211 wakeup((caddr_t)&ipc); 212 return (1); 213 214 case PT_KILL: /* kill the child process */ 215 wakeup((caddr_t)&ipc); 216 exit(p, (int)p->p_xstat); 217 218 default: 219 error: 220 ipc.ip_req = -1; 221 } 222 wakeup((caddr_t)&ipc); 223 return (0); 224 } 225