/* $OpenBSD: kvm_proc.c,v 1.3 1996/10/26 08:44:08 tholo Exp $ */ /*- * Copyright (c) 1994, 1995 Charles M. Hannum. All rights reserved. * Copyright (c) 1989, 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software developed by the Computer Systems * Engineering group at Lawrence Berkeley Laboratory under DARPA contract * BG 91-66 and contributed to Berkeley. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "@(#)kvm_proc.c 8.3 (Berkeley) 9/23/93"; #endif /* LIBC_SCCS and not lint */ /* * Proc traversal interface for kvm. ps and w are (probably) the exclusive * users of this code, so we've factored it out into a separate module. * Thus, we keep this grunge out of the other kvm applications (i.e., * most other applications are interested only in open/close/read/nlist). */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "kvm_private.h" #define KREAD(kd, addr, obj) \ (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) int _kvm_readfromcore __P((kvm_t *, u_long, u_long)); int _kvm_readfrompager __P((kvm_t *, struct vm_object *, u_long)); ssize_t kvm_uread __P((kvm_t *, const struct proc *, u_long, char *, size_t)); static char **kvm_argv __P((kvm_t *, const struct proc *, u_long, int, int)); static int kvm_deadprocs __P((kvm_t *, int, int, u_long, u_long, int)); static char **kvm_doargv __P((kvm_t *, const struct kinfo_proc *, int, void (*)(struct ps_strings *, u_long *, int *))); static int kvm_proclist __P((kvm_t *, int, int, struct proc *, struct kinfo_proc *, int)); static int proc_verify __P((kvm_t *, u_long, const struct proc *)); static void ps_str_a __P((struct ps_strings *, u_long *, int *)); static void ps_str_e __P((struct ps_strings *, u_long *, int *)); char * _kvm_uread(kd, p, va, cnt) kvm_t *kd; const struct proc *p; u_long va; u_long *cnt; { register u_long addr, head; register u_long offset; struct vm_map_entry vme; struct vm_object vmo; int rv; if (kd->swapspc == 0) { kd->swapspc = (char *)_kvm_malloc(kd, kd->nbpg); if (kd->swapspc == 0) return (0); } /* * Look through the address map for the memory object * that corresponds to the given virtual address. * The header just has the entire valid range. */ head = (u_long)&p->p_vmspace->vm_map.header; addr = head; while (1) { if (KREAD(kd, addr, &vme)) return (0); if (va >= vme.start && va < vme.end && vme.object.vm_object != 0) break; addr = (u_long)vme.next; if (addr == head) return (0); } /* * We found the right object -- follow shadow links. */ offset = va - vme.start + vme.offset; addr = (u_long)vme.object.vm_object; while (1) { /* Try reading the page from core first. */ if ((rv = _kvm_readfromcore(kd, addr, offset))) break; if (KREAD(kd, addr, &vmo)) return (0); /* If there is a pager here, see if it has the page. */ if (vmo.pager != 0 && (rv = _kvm_readfrompager(kd, &vmo, offset))) break; /* Move down the shadow chain. */ addr = (u_long)vmo.shadow; if (addr == 0) return (0); offset += vmo.shadow_offset; } if (rv == -1) return (0); /* Found the page. */ offset %= kd->nbpg; *cnt = kd->nbpg - offset; return (&kd->swapspc[offset]); } #define vm_page_hash(kd, object, offset) \ (((u_long)object + (u_long)(offset / kd->nbpg)) & kd->vm_page_hash_mask) int _kvm_coreinit(kd) kvm_t *kd; { struct nlist nlist[3]; nlist[0].n_name = "_vm_page_buckets"; nlist[1].n_name = "_vm_page_hash_mask"; nlist[2].n_name = 0; if (kvm_nlist(kd, nlist) != 0) return (-1); if (KREAD(kd, nlist[0].n_value, &kd->vm_page_buckets) || KREAD(kd, nlist[1].n_value, &kd->vm_page_hash_mask)) return (-1); return (0); } int _kvm_readfromcore(kd, object, offset) kvm_t *kd; u_long object, offset; { u_long addr; struct pglist bucket; struct vm_page mem; off_t seekpoint; if (kd->vm_page_buckets == 0 && _kvm_coreinit(kd)) return (-1); addr = (u_long)&kd->vm_page_buckets[vm_page_hash(kd, object, offset)]; if (KREAD(kd, addr, &bucket)) return (-1); addr = (u_long)bucket.tqh_first; offset &= ~(kd->nbpg -1); while (1) { if (addr == 0) return (0); if (KREAD(kd, addr, &mem)) return (-1); if ((u_long)mem.object == object && (u_long)mem.offset == offset) break; addr = (u_long)mem.hashq.tqe_next; } seekpoint = mem.phys_addr; if (lseek(kd->pmfd, seekpoint, 0) == -1) return (-1); if (read(kd->pmfd, kd->swapspc, kd->nbpg) != kd->nbpg) return (-1); return (1); } int _kvm_readfrompager(kd, vmop, offset) kvm_t *kd; struct vm_object *vmop; u_long offset; { u_long addr; struct pager_struct pager; struct swpager swap; int ix; struct swblock swb; off_t seekpoint; /* Read in the pager info and make sure it's a swap device. */ addr = (u_long)vmop->pager; if (KREAD(kd, addr, &pager) || pager.pg_type != PG_SWAP) return (-1); /* Read in the swap_pager private data. */ addr = (u_long)pager.pg_data; if (KREAD(kd, addr, &swap)) return (-1); /* * Calculate the paging offset, and make sure it's within the * bounds of the pager. */ offset += vmop->paging_offset; ix = offset / dbtob(swap.sw_bsize); #if 0 if (swap.sw_blocks == 0 || ix >= swap.sw_nblocks) return (-1); #else if (swap.sw_blocks == 0 || ix >= swap.sw_nblocks) { int i; printf("BUG BUG BUG BUG:\n"); printf("object %x offset %x pgoffset %x pager %x swpager %x\n", vmop, offset - vmop->paging_offset, vmop->paging_offset, vmop->pager, pager.pg_data); printf("osize %x bsize %x blocks %x nblocks %x\n", swap.sw_osize, swap.sw_bsize, swap.sw_blocks, swap.sw_nblocks); for (ix = 0; ix < swap.sw_nblocks; ix++) { addr = (u_long)&swap.sw_blocks[ix]; if (KREAD(kd, addr, &swb)) return (0); printf("sw_blocks[%d]: block %x mask %x\n", ix, swb.swb_block, swb.swb_mask); } return (-1); } #endif /* Read in the swap records. */ addr = (u_long)&swap.sw_blocks[ix]; if (KREAD(kd, addr, &swb)) return (-1); /* Calculate offset within pager. */ offset %= dbtob(swap.sw_bsize); /* Check that the page is actually present. */ if ((swb.swb_mask & (1 << (offset / kd->nbpg))) == 0) return (0); if (!ISALIVE(kd)) return (-1); /* Calculate the physical address and read the page. */ seekpoint = dbtob(swb.swb_block) + (offset & ~(kd->nbpg -1)); if (lseek(kd->swfd, seekpoint, 0) == -1) return (-1); if (read(kd->swfd, kd->swapspc, kd->nbpg) != kd->nbpg) return (-1); return (1); } /* * Read proc's from memory file into buffer bp, which has space to hold * at most maxcnt procs. */ static int kvm_proclist(kd, what, arg, p, bp, maxcnt) kvm_t *kd; int what, arg; struct proc *p; struct kinfo_proc *bp; int maxcnt; { register int cnt = 0; struct eproc eproc; struct pgrp pgrp; struct session sess; struct tty tty; struct proc proc; for (; cnt < maxcnt && p != NULL; p = proc.p_list.le_next) { if (KREAD(kd, (u_long)p, &proc)) { _kvm_err(kd, kd->program, "can't read proc at %x", p); return (-1); } if (KREAD(kd, (u_long)proc.p_cred, &eproc.e_pcred) == 0) KREAD(kd, (u_long)eproc.e_pcred.pc_ucred, &eproc.e_ucred); switch(what) { case KERN_PROC_PID: if (proc.p_pid != (pid_t)arg) continue; break; case KERN_PROC_UID: if (eproc.e_ucred.cr_uid != (uid_t)arg) continue; break; case KERN_PROC_RUID: if (eproc.e_pcred.p_ruid != (uid_t)arg) continue; break; } /* * We're going to add another proc to the set. If this * will overflow the buffer, assume the reason is because * nprocs (or the proc list) is corrupt and declare an error. */ if (cnt >= maxcnt) { _kvm_err(kd, kd->program, "nprocs corrupt"); return (-1); } /* * gather eproc */ eproc.e_paddr = p; if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) { _kvm_err(kd, kd->program, "can't read pgrp at %x", proc.p_pgrp); return (-1); } eproc.e_sess = pgrp.pg_session; eproc.e_pgid = pgrp.pg_id; eproc.e_jobc = pgrp.pg_jobc; if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) { _kvm_err(kd, kd->program, "can't read session at %x", pgrp.pg_session); return (-1); } if ((proc.p_flag & P_CONTROLT) && sess.s_ttyp != NULL) { if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) { _kvm_err(kd, kd->program, "can't read tty at %x", sess.s_ttyp); return (-1); } eproc.e_tdev = tty.t_dev; eproc.e_tsess = tty.t_session; if (tty.t_pgrp != NULL) { if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) { _kvm_err(kd, kd->program, "can't read tpgrp at &x", tty.t_pgrp); return (-1); } eproc.e_tpgid = pgrp.pg_id; } else eproc.e_tpgid = -1; } else eproc.e_tdev = NODEV; eproc.e_flag = sess.s_ttyvp ? EPROC_CTTY : 0; if (sess.s_leader == p) eproc.e_flag |= EPROC_SLEADER; if (proc.p_wmesg) (void)kvm_read(kd, (u_long)proc.p_wmesg, eproc.e_wmesg, WMESGLEN); (void)kvm_read(kd, (u_long)proc.p_vmspace, (char *)&eproc.e_vm, sizeof(eproc.e_vm)); eproc.e_xsize = eproc.e_xrssize = 0; eproc.e_xccount = eproc.e_xswrss = 0; switch (what) { case KERN_PROC_PGRP: if (eproc.e_pgid != (pid_t)arg) continue; break; case KERN_PROC_TTY: if ((proc.p_flag & P_CONTROLT) == 0 || eproc.e_tdev != (dev_t)arg) continue; break; } bcopy(&proc, &bp->kp_proc, sizeof(proc)); bcopy(&eproc, &bp->kp_eproc, sizeof(eproc)); ++bp; ++cnt; } return (cnt); } /* * Build proc info array by reading in proc list from a crash dump. * Return number of procs read. maxcnt is the max we will read. */ static int kvm_deadprocs(kd, what, arg, a_allproc, a_zombproc, maxcnt) kvm_t *kd; int what, arg; u_long a_allproc; u_long a_zombproc; int maxcnt; { register struct kinfo_proc *bp = kd->procbase; register int acnt, zcnt; struct proc *p; if (KREAD(kd, a_allproc, &p)) { _kvm_err(kd, kd->program, "cannot read allproc"); return (-1); } acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt); if (acnt < 0) return (acnt); if (KREAD(kd, a_zombproc, &p)) { _kvm_err(kd, kd->program, "cannot read zombproc"); return (-1); } zcnt = kvm_proclist(kd, what, arg, p, bp + acnt, maxcnt - acnt); if (zcnt < 0) zcnt = 0; return (acnt + zcnt); } struct kinfo_proc * kvm_getprocs(kd, op, arg, cnt) kvm_t *kd; int op, arg; int *cnt; { size_t size; int mib[4], st, nprocs; if (kd->procbase != 0) { free((void *)kd->procbase); /* * Clear this pointer in case this call fails. Otherwise, * kvm_close() will free it again. */ kd->procbase = 0; } if (ISALIVE(kd)) { size = 0; mib[0] = CTL_KERN; mib[1] = KERN_PROC; mib[2] = op; mib[3] = arg; st = sysctl(mib, 4, NULL, &size, NULL, 0); if (st == -1) { _kvm_syserr(kd, kd->program, "kvm_getprocs"); return (0); } kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size); if (kd->procbase == 0) return (0); st = sysctl(mib, 4, kd->procbase, &size, NULL, 0); if (st == -1) { _kvm_syserr(kd, kd->program, "kvm_getprocs"); return (0); } if (size % sizeof(struct kinfo_proc) != 0) { _kvm_err(kd, kd->program, "proc size mismatch (%d total, %d chunks)", size, sizeof(struct kinfo_proc)); return (0); } nprocs = size / sizeof(struct kinfo_proc); } else { struct nlist nl[4], *p; nl[0].n_name = "_nprocs"; nl[1].n_name = "_allproc"; nl[2].n_name = "_zombproc"; nl[3].n_name = 0; if (kvm_nlist(kd, nl) != 0) { for (p = nl; p->n_type != 0; ++p) ; _kvm_err(kd, kd->program, "%s: no such symbol", p->n_name); return (0); } if (KREAD(kd, nl[0].n_value, &nprocs)) { _kvm_err(kd, kd->program, "can't read nprocs"); return (0); } size = nprocs * sizeof(struct kinfo_proc); kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size); if (kd->procbase == 0) return (0); nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value, nl[2].n_value, nprocs); #ifdef notdef size = nprocs * sizeof(struct kinfo_proc); (void)realloc(kd->procbase, size); #endif } *cnt = nprocs; return (kd->procbase); } void _kvm_freeprocs(kd) kvm_t *kd; { if (kd->procbase) { free(kd->procbase); kd->procbase = 0; } } void * _kvm_realloc(kd, p, n) kvm_t *kd; void *p; size_t n; { void *np = (void *)realloc(p, n); if (np == 0) _kvm_err(kd, kd->program, "out of memory"); return (np); } #ifndef MAX #define MAX(a, b) ((a) > (b) ? (a) : (b)) #endif /* * Read in an argument vector from the user address space of process p. * addr if the user-space base address of narg null-terminated contiguous * strings. This is used to read in both the command arguments and * environment strings. Read at most maxcnt characters of strings. */ static char ** kvm_argv(kd, p, addr, narg, maxcnt) kvm_t *kd; const struct proc *p; register u_long addr; register int narg; register int maxcnt; { register char *np, *cp, *ep, *ap; register u_long oaddr = -1; register int len, cc; register char **argv; /* * Check that there aren't an unreasonable number of agruments, * and that the address is in user space. */ if (narg > ARG_MAX || addr < VM_MIN_ADDRESS || addr >= VM_MAXUSER_ADDRESS) return (0); if (kd->argv == 0) { /* * Try to avoid reallocs. */ kd->argc = MAX(narg + 1, 32); kd->argv = (char **)_kvm_malloc(kd, kd->argc * sizeof(*kd->argv)); if (kd->argv == 0) return (0); } else if (narg + 1 > kd->argc) { kd->argc = MAX(2 * kd->argc, narg + 1); kd->argv = (char **)_kvm_realloc(kd, kd->argv, kd->argc * sizeof(*kd->argv)); if (kd->argv == 0) return (0); } if (kd->argspc == 0) { kd->argspc = (char *)_kvm_malloc(kd, kd->nbpg); if (kd->argspc == 0) return (0); kd->arglen = kd->nbpg; } if (kd->argbuf == 0) { kd->argbuf = (char *)_kvm_malloc(kd, kd->nbpg); if (kd->argbuf == 0) return (0); } cc = sizeof(char *) * narg; if (kvm_uread(kd, p, addr, (char *)kd->argv, cc) != cc) return (0); ap = np = kd->argspc; argv = kd->argv; len = 0; /* * Loop over pages, filling in the argument vector. */ while (argv < kd->argv + narg && *argv != 0) { addr = (u_long)*argv & ~(kd->nbpg - 1); if (addr != oaddr) { if (kvm_uread(kd, p, addr, kd->argbuf, kd->nbpg) != kd->nbpg) return (0); oaddr = addr; } addr = (u_long)*argv & (kd->nbpg - 1); cp = kd->argbuf + addr; cc = kd->nbpg - addr; if (maxcnt > 0 && cc > maxcnt - len) cc = maxcnt - len;; ep = memchr(cp, '\0', cc); if (ep != 0) cc = ep - cp + 1; if (len + cc > kd->arglen) { register int off; register char **pp; register char *op = kd->argspc; kd->arglen *= 2; kd->argspc = (char *)_kvm_realloc(kd, kd->argspc, kd->arglen); if (kd->argspc == 0) return (0); /* * Adjust argv pointers in case realloc moved * the string space. */ off = kd->argspc - op; for (pp = kd->argv; pp < argv; pp++) *pp += off; ap += off; np += off; } memcpy(np, cp, cc); np += cc; len += cc; if (ep != 0) { *argv++ = ap; ap = np; } else *argv += cc; if (maxcnt > 0 && len >= maxcnt) { /* * We're stopping prematurely. Terminate the * current string. */ if (ep == 0) { *np = '\0'; *argv++ = ap; } break; } } /* Make sure argv is terminated. */ *argv = 0; return (kd->argv); } static void ps_str_a(p, addr, n) struct ps_strings *p; u_long *addr; int *n; { *addr = (u_long)p->ps_argvstr; *n = p->ps_nargvstr; } static void ps_str_e(p, addr, n) struct ps_strings *p; u_long *addr; int *n; { *addr = (u_long)p->ps_envstr; *n = p->ps_nenvstr; } /* * Determine if the proc indicated by p is still active. * This test is not 100% foolproof in theory, but chances of * being wrong are very low. */ static int proc_verify(kd, kernp, p) kvm_t *kd; u_long kernp; const struct proc *p; { struct proc kernproc; /* * Just read in the whole proc. It's not that big relative * to the cost of the read system call. */ if (kvm_read(kd, kernp, (char *)&kernproc, sizeof(kernproc)) != sizeof(kernproc)) return (0); return (p->p_pid == kernproc.p_pid && (kernproc.p_stat != SZOMB || p->p_stat == SZOMB)); } static char ** kvm_doargv(kd, kp, nchr, info) kvm_t *kd; const struct kinfo_proc *kp; int nchr; void (*info)(struct ps_strings *, u_long *, int *); { register const struct proc *p = &kp->kp_proc; register char **ap; u_long addr; int cnt; struct ps_strings arginfo; static struct ps_strings *ps; if (ps == NULL) { struct _ps_strings _ps; int mib[2]; size_t len; mib[0] = CTL_VM; mib[1] = VM_PSSTRINGS; len = sizeof(_ps); sysctl(mib, 2, &_ps, &len, NULL, 0); ps = (struct ps_strings *)_ps.val; } /* * Pointers are stored at the top of the user stack. */ if (p->p_stat == SZOMB || kvm_uread(kd, p, (u_long)ps, (char *)&arginfo, sizeof(arginfo)) != sizeof(arginfo)) return (0); (*info)(&arginfo, &addr, &cnt); if (cnt == 0) return (0); ap = kvm_argv(kd, p, addr, cnt, nchr); /* * For live kernels, make sure this process didn't go away. */ if (ap != 0 && ISALIVE(kd) && !proc_verify(kd, (u_long)kp->kp_eproc.e_paddr, p)) ap = 0; return (ap); } /* * Get the command args. This code is now machine independent. */ char ** kvm_getargv(kd, kp, nchr) kvm_t *kd; const struct kinfo_proc *kp; int nchr; { return (kvm_doargv(kd, kp, nchr, ps_str_a)); } char ** kvm_getenvv(kd, kp, nchr) kvm_t *kd; const struct kinfo_proc *kp; int nchr; { return (kvm_doargv(kd, kp, nchr, ps_str_e)); } /* * Read from user space. The user context is given by p. */ ssize_t kvm_uread(kd, p, uva, buf, len) kvm_t *kd; register const struct proc *p; register u_long uva; register char *buf; register size_t len; { register char *cp; cp = buf; while (len > 0) { register int cc; register char *dp; u_long cnt; dp = _kvm_uread(kd, p, uva, &cnt); if (dp == 0) { _kvm_err(kd, 0, "invalid address (%x)", uva); return (0); } cc = MIN(cnt, len); bcopy(dp, cp, cc); cp += cc; uva += cc; len -= cc; } return (ssize_t)(cp - buf); }