xref: /dragonfly/lib/libkvm/kvm_file.c (revision 9348a738)
1 /*-
2  * Copyright (c) 1989, 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)kvm_file.c	8.1 (Berkeley) 6/4/93
30  * $FreeBSD: src/lib/libkvm/kvm_file.c,v 1.11 2000/02/18 16:39:00 peter Exp $
31  */
32 
33 /*
34  * File list interface for kvm.
35  */
36 
37 #include <sys/user.h>	/* MUST BE FIRST */
38 #include <sys/param.h>
39 #include <sys/proc.h>
40 #define _KERNEL
41 #include <sys/file.h>
42 #undef _KERNEL
43 #include <sys/stat.h>
44 #include <sys/ioctl.h>
45 #include <sys/kinfo.h>
46 #include <nlist.h>
47 #include <kvm.h>
48 
49 #include <vm/vm.h>
50 #include <vm/vm_param.h>
51 #include <vm/swap_pager.h>
52 
53 #include <sys/sysctl.h>
54 
55 #include <limits.h>
56 #include <ndbm.h>
57 #include <paths.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 
62 #include "kvm_private.h"
63 
64 #define KREAD(kd, addr, obj) \
65 	(kvm_read(kd, addr, obj, sizeof(*obj)) != sizeof(*obj))
66 
67 /* XXX copied from sys/kern/subr_kcore.c */
68 static void
69 kcore_make_file(struct kinfo_file *ufile, struct file *kfile,
70     pid_t pid, uid_t owner, int n)
71 {
72 	bzero(ufile, sizeof(*ufile));
73 	ufile->f_size = sizeof(*ufile);
74 	ufile->f_pid = pid;
75 	ufile->f_uid = owner;
76 
77 	ufile->f_fd = n;
78 	ufile->f_file = kfile;
79 	ufile->f_data = kfile->f_data;
80 	ufile->f_type = kfile->f_type;
81 	ufile->f_count = kfile->f_count;
82 	ufile->f_msgcount = kfile->f_msgcount;
83 	ufile->f_offset = kfile->f_offset;
84 	ufile->f_flag = kfile->f_flag;
85 }
86 
87 /*
88  * Get file structures.
89  */
90 static int
91 kvm_deadfiles(kvm_t *kd, struct kinfo_proc *kproc, int kproc_cnt, int nfiles)
92 {
93 	struct kinfo_file *kinfo_file = (struct kinfo_file *)kd->argspc;
94 	struct fdnode *fd_files;
95 	int i, fd_nfiles, found = 0;
96 
97 	fd_nfiles = NDFILE;
98 	fd_files = malloc(fd_nfiles * sizeof(struct fdnode));
99 	if (fd_files == NULL) {
100 		_kvm_err(kd, kd->program, "alloc fd_files failed");
101 		return 0;
102 	}
103 
104 	for (i = 0; i < kproc_cnt; ++i) {
105 		const struct kinfo_proc *kp = &kproc[i];
106 		struct filedesc fdp;
107 		int n, f;
108 
109 		if (kp->kp_fd == 0)
110 			continue;
111 		if (KREAD(kd, kp->kp_fd, &fdp)) {
112 			_kvm_err(kd, kd->program, "can't read fdp");
113 			free(fd_files);
114 			return 0;
115 		}
116 		if (fdp.fd_files == NULL)
117 			continue;
118 
119 		if (fdp.fd_nfiles > fd_nfiles) {
120 			struct fdnode *new_fd_files;
121 
122 			fd_nfiles = fdp.fd_nfiles;
123 			new_fd_files =
124 			    malloc(fd_nfiles * sizeof(struct fdnode));
125 			free(fd_files);
126 			if (new_fd_files == NULL) {
127 				_kvm_err(kd, kd->program,
128 				    "realloc fd_files failed");
129 				return 0;
130 			}
131 			fd_files = new_fd_files;
132 		}
133 		n = fdp.fd_nfiles * sizeof(struct fdnode);
134 
135 		if (kvm_read(kd, (uintptr_t)fdp.fd_files, fd_files, n) != n) {
136 			_kvm_err(kd, kd->program, "can't read fd_files");
137 			free(fd_files);
138 			return 0;
139 		}
140 		for (f = 0; f < fdp.fd_nfiles; ++f) {
141 			struct file kf;
142 
143 			if (fd_files[f].fp == NULL)
144 				continue;
145 			if (KREAD(kd, (uintptr_t)fd_files[f].fp, &kf)) {
146 				_kvm_err(kd, kd->program, "can't read file");
147 				free(fd_files);
148 				return 0;
149 			}
150 
151 			kcore_make_file(kinfo_file, &kf,
152 			    kp->kp_pid, kp->kp_uid, f);
153 			kinfo_file++;
154 			found++;
155 
156 			if (found == nfiles) {
157 				size_t size;
158 
159 				nfiles *= 2;
160 				size = nfiles * sizeof(struct kinfo_file);
161 
162 				kd->argspc = _kvm_realloc(kd, kd->argspc, size);
163 				if (kd->argspc == NULL) {
164 					free(fd_files);
165 					return 0;
166 				}
167 				kd->arglen = size;
168 
169 				kinfo_file = (struct kinfo_file *)kd->argspc;
170 				kinfo_file += found;
171 			}
172 		}
173 	}
174 	free(fd_files);
175 	return found;
176 }
177 
178 struct kinfo_file *
179 kvm_getfiles(kvm_t *kd, int op, int arg, int *cnt)
180 {
181 	int nfiles;
182 	size_t size;
183 
184 	if (kvm_ishost(kd)) {
185 		int mib[2], st;
186 
187 		size = 0;
188 		mib[0] = CTL_KERN;
189 		mib[1] = KERN_FILE;
190 		st = sysctl(mib, 2, NULL, &size, NULL, 0);
191 		if (st == -1) {
192 			_kvm_syserr(kd, kd->program, "sysctl KERN_FILE failed");
193 			return NULL;
194 		}
195 		if (kd->argspc == NULL)
196 			kd->argspc = _kvm_malloc(kd, size);
197 		else if (kd->arglen < size)
198 			kd->argspc = _kvm_realloc(kd, kd->argspc, size);
199 		if (kd->argspc == NULL)
200 			return NULL;
201 		kd->arglen = size;
202 		st = sysctl(mib, 2, kd->argspc, &size, NULL, 0);
203 		if (st == -1 || size % sizeof(struct kinfo_file) != 0) {
204 			_kvm_syserr(kd, kd->program, "sysctl KERN_FILE failed");
205 			return NULL;
206 		}
207 		nfiles = size / sizeof(struct kinfo_file);
208 	} else {
209 		struct kinfo_proc *kproc0, *kproc;
210 		int kproc_cnt, kproc_len;
211 		struct nlist nl[2];
212 
213 		/*
214 		 * Get all processes and save them in kproc.
215 		 */
216 		kproc0 = kvm_getprocs(kd, KERN_PROC_ALL, 0, &kproc_cnt);
217 		if (kproc0 == NULL)
218 			return NULL;
219 		kproc_len = kproc_cnt * sizeof(struct kinfo_proc);
220 		kproc = malloc(kproc_len);
221 		if (kproc == NULL) {
222 			_kvm_syserr(kd, kd->program,
223 			    "malloc kinfo_proc failed");
224 			return NULL;
225 		}
226 		memcpy(kproc, kproc0, kproc_len);
227 
228 		/*
229 		 * Get the # of files
230 		 */
231 		memset(nl, 0, sizeof(nl));
232 		nl[0].n_name = "_nfiles";
233 		if (kvm_nlist(kd, nl) != 0) {
234 			_kvm_err(kd, kd->program, "%s: no such symbol",
235 			    nl[0].n_name);
236 			free(kproc);
237 			return NULL;
238 		}
239 		if (KREAD(kd, nl[0].n_value, &nfiles)) {
240 			_kvm_err(kd, kd->program, "can't read nfiles");
241 			free(kproc);
242 			return NULL;
243 		}
244 
245 		/*
246 		 * stdio/stderr/stdout are normally duplicated
247 		 * across all processes.
248 		 */
249 		nfiles += (kproc_cnt * 3);
250 		size = nfiles * sizeof(struct kinfo_file);
251 		if (kd->argspc == NULL)
252 			kd->argspc = _kvm_malloc(kd, size);
253 		else if (kd->arglen < size)
254 			kd->argspc = _kvm_realloc(kd, kd->argspc, size);
255 		if (kd->argspc == NULL) {
256 			free(kproc);
257 			return NULL;
258 		}
259 		kd->arglen = size;
260 
261 		nfiles = kvm_deadfiles(kd, kproc, kproc_cnt, nfiles);
262 		free(kproc);
263 
264 		if (nfiles == 0)
265 			return NULL;
266 	}
267 	*cnt = nfiles;
268 	return (struct kinfo_file *)(kd->argspc);
269 }
270