xref: /dragonfly/lib/libkvm/kvm_file.c (revision e6d22e9b)
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 #define _KERNEL
40 #include <sys/file.h>
41 #undef _KERNEL
42 #include <sys/stat.h>
43 #include <sys/ioctl.h>
44 #include <sys/kinfo.h>
45 #include <nlist.h>
46 
47 #include <vm/vm.h>
48 #include <vm/vm_param.h>
49 #include <vm/swap_pager.h>
50 
51 #include <sys/sysctl.h>
52 
53 #include <limits.h>
54 #include <ndbm.h>
55 #include <paths.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 
60 #include "kvm.h"
61 #include "kvm_private.h"
62 
63 #define KREAD(kd, addr, obj) \
64 	(kvm_read(kd, addr, obj, sizeof(*obj)) != sizeof(*obj))
65 
66 /* XXX copied from sys/kern/subr_kcore.c */
67 static void
68 kcore_make_file(struct kinfo_file *ufile, struct file *kfile,
69     pid_t pid, uid_t owner, int n)
70 {
71 	bzero(ufile, sizeof(*ufile));
72 	ufile->f_size = sizeof(*ufile);
73 	ufile->f_pid = pid;
74 	ufile->f_uid = owner;
75 
76 	ufile->f_fd = n;
77 	ufile->f_file = kfile;
78 	ufile->f_data = kfile->f_data;
79 	ufile->f_type = kfile->f_type;
80 	ufile->f_count = kfile->f_count;
81 	ufile->f_msgcount = kfile->f_msgcount;
82 	ufile->f_offset = kfile->f_offset;
83 	ufile->f_flag = kfile->f_flag;
84 }
85 
86 /*
87  * Get file structures.
88  */
89 static int
90 kvm_deadfiles(kvm_t *kd, struct kinfo_proc *kproc, int kproc_cnt, int nfiles)
91 {
92 	struct kinfo_file *kinfo_file = (struct kinfo_file *)kd->argspc;
93 	struct fdnode *fd_files;
94 	size_t size;
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 				nfiles *= 2;
158 				size = nfiles * sizeof(struct kinfo_file);
159 
160 				kd->argspc = _kvm_realloc(kd, kd->argspc, size);
161 				if (kd->argspc == NULL) {
162 					free(fd_files);
163 					return 0;
164 				}
165 				kd->arglen = size;
166 
167 				kinfo_file = (struct kinfo_file *)kd->argspc;
168 				kinfo_file += found;
169 			}
170 		}
171 	}
172 	free(fd_files);
173 	return found;
174 }
175 
176 struct kinfo_file *
177 kvm_getfiles(kvm_t *kd, int op __unused, int arg __unused, int *cnt)
178 {
179 	int nfiles;
180 	size_t size;
181 
182 	if (kvm_ishost(kd)) {
183 		int mib[2], st;
184 
185 		size = 0;
186 		mib[0] = CTL_KERN;
187 		mib[1] = KERN_FILE;
188 		st = sysctl(mib, 2, NULL, &size, NULL, 0);
189 		if (st == -1) {
190 			_kvm_syserr(kd, kd->program, "sysctl KERN_FILE failed");
191 			return NULL;
192 		}
193 		if (kd->argspc == NULL)
194 			kd->argspc = _kvm_malloc(kd, size);
195 		else if (kd->arglen < (ssize_t)size)
196 			kd->argspc = _kvm_realloc(kd, kd->argspc, size);
197 		if (kd->argspc == NULL)
198 			return NULL;
199 		kd->arglen = size;
200 		st = sysctl(mib, 2, kd->argspc, &size, NULL, 0);
201 		if (st == -1 || size % sizeof(struct kinfo_file) != 0) {
202 			_kvm_syserr(kd, kd->program, "sysctl KERN_FILE failed");
203 			return NULL;
204 		}
205 		nfiles = size / sizeof(struct kinfo_file);
206 	} else {
207 		struct kinfo_proc *kproc0, *kproc;
208 		int kproc_cnt, kproc_len;
209 		struct nlist nl[2];
210 
211 		/*
212 		 * Get all processes and save them in kproc.
213 		 */
214 		kproc0 = kvm_getprocs(kd, KERN_PROC_ALL, 0, &kproc_cnt);
215 		if (kproc0 == NULL)
216 			return NULL;
217 		kproc_len = kproc_cnt * sizeof(struct kinfo_proc);
218 		kproc = malloc(kproc_len);
219 		if (kproc == NULL) {
220 			_kvm_syserr(kd, kd->program,
221 			    "malloc kinfo_proc failed");
222 			return NULL;
223 		}
224 		memcpy(kproc, kproc0, kproc_len);
225 
226 		/*
227 		 * Get the # of files
228 		 */
229 		memset(nl, 0, sizeof(nl));
230 		nl[0].n_name = "_nfiles";
231 		if (kvm_nlist(kd, nl) != 0) {
232 			_kvm_err(kd, kd->program, "%s: no such symbol",
233 			    nl[0].n_name);
234 			free(kproc);
235 			return NULL;
236 		}
237 		if (KREAD(kd, nl[0].n_value, &nfiles)) {
238 			_kvm_err(kd, kd->program, "can't read nfiles");
239 			free(kproc);
240 			return NULL;
241 		}
242 
243 		/*
244 		 * stdio/stderr/stdout are normally duplicated
245 		 * across all processes.
246 		 */
247 		nfiles += (kproc_cnt * 3);
248 		size = nfiles * sizeof(struct kinfo_file);
249 		if (kd->argspc == NULL)
250 			kd->argspc = _kvm_malloc(kd, size);
251 		else if (kd->arglen < (ssize_t)size)
252 			kd->argspc = _kvm_realloc(kd, kd->argspc, size);
253 		if (kd->argspc == NULL) {
254 			free(kproc);
255 			return NULL;
256 		}
257 		kd->arglen = size;
258 
259 		nfiles = kvm_deadfiles(kd, kproc, kproc_cnt, nfiles);
260 		free(kproc);
261 
262 		if (nfiles == 0)
263 			return NULL;
264 	}
265 	*cnt = nfiles;
266 	return (struct kinfo_file *)(kd->argspc);
267 }
268