1*766Scarlsonj /*
2*766Scarlsonj * CDDL HEADER START
3*766Scarlsonj *
4*766Scarlsonj * The contents of this file are subject to the terms of the
5*766Scarlsonj * Common Development and Distribution License (the "License").
6*766Scarlsonj * You may not use this file except in compliance with the License.
7*766Scarlsonj *
8*766Scarlsonj * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9*766Scarlsonj * or http://www.opensolaris.org/os/licensing.
10*766Scarlsonj * See the License for the specific language governing permissions
11*766Scarlsonj * and limitations under the License.
12*766Scarlsonj *
13*766Scarlsonj * When distributing Covered Code, include this CDDL HEADER in each
14*766Scarlsonj * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15*766Scarlsonj * If applicable, add the following below this CDDL HEADER, with the
16*766Scarlsonj * fields enclosed by brackets "[]" replaced with your own identifying
17*766Scarlsonj * information: Portions Copyright [yyyy] [name of copyright owner]
18*766Scarlsonj *
19*766Scarlsonj * CDDL HEADER END
20*766Scarlsonj */
21*766Scarlsonj
22*766Scarlsonj /*
23*766Scarlsonj * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
24*766Scarlsonj * Use is subject to license terms.
25*766Scarlsonj */
26*766Scarlsonj
27*766Scarlsonj #pragma ident "%Z%%M% %I% %E% SMI"
28*766Scarlsonj
29*766Scarlsonj /*
30*766Scarlsonj * This module contains functions used for reading and writing the scratch zone
31*766Scarlsonj * translation files. These files are used by Live Upgrade to keep track of
32*766Scarlsonj * mappings between actual kernel zone names and the zones in an alternate boot
33*766Scarlsonj * environment.
34*766Scarlsonj *
35*766Scarlsonj * The functions are MT-safe.
36*766Scarlsonj *
37*766Scarlsonj * The file format looks like this:
38*766Scarlsonj *
39*766Scarlsonj * <zonename> <kernel-zonename> <alt-root>
40*766Scarlsonj *
41*766Scarlsonj * The expected usage model is:
42*766Scarlsonj *
43*766Scarlsonj * fp = zonecfg_open_scratch("", B_TRUE);
44*766Scarlsonj * zonecfg_lock_scratch(fp);
45*766Scarlsonj * if (zonecfg_find_scratch(fp, zonename, altroot, NULL, 0) == 0) {
46*766Scarlsonj * handle error; zone already mounted
47*766Scarlsonj * }
48*766Scarlsonj * mount zone here
49*766Scarlsonj * zonecfg_add_scratch(fp, zonename, kernname, altroot);
50*766Scarlsonj * zonecfg_close_scratch(fp);
51*766Scarlsonj * fp = zonecfg_open_scratch(zoneroot, B_TRUE);
52*766Scarlsonj * ftruncate(fileno(fp), 0);
53*766Scarlsonj * zonecfg_add_scratch(fp, zonename, kernname, "/");
54*766Scarlsonj * zonecfg_close_scratch(fp);
55*766Scarlsonj */
56*766Scarlsonj
57*766Scarlsonj #include <stdio.h>
58*766Scarlsonj #include <unistd.h>
59*766Scarlsonj #include <fcntl.h>
60*766Scarlsonj #include <errno.h>
61*766Scarlsonj #include <string.h>
62*766Scarlsonj #include <sys/types.h>
63*766Scarlsonj #include <sys/stat.h>
64*766Scarlsonj #include <sys/param.h>
65*766Scarlsonj #include <libzonecfg.h>
66*766Scarlsonj
67*766Scarlsonj #define PATH_MAPFILE "tmp/.alt.lu-zone-map"
68*766Scarlsonj
69*766Scarlsonj static int
lock_op(int fd,int type)70*766Scarlsonj lock_op(int fd, int type)
71*766Scarlsonj {
72*766Scarlsonj struct flock lock;
73*766Scarlsonj
74*766Scarlsonj lock.l_type = type;
75*766Scarlsonj lock.l_whence = SEEK_SET;
76*766Scarlsonj lock.l_start = 0;
77*766Scarlsonj lock.l_len = 0;
78*766Scarlsonj
79*766Scarlsonj return (fcntl(fd, F_SETLKW, &lock));
80*766Scarlsonj }
81*766Scarlsonj
82*766Scarlsonj FILE *
zonecfg_open_scratch(const char * rootpath,boolean_t createfile)83*766Scarlsonj zonecfg_open_scratch(const char *rootpath, boolean_t createfile)
84*766Scarlsonj {
85*766Scarlsonj mode_t oldmask = umask(0);
86*766Scarlsonj struct stat lbuf, fbuf;
87*766Scarlsonj int fd, flags;
88*766Scarlsonj FILE *fp;
89*766Scarlsonj char mapfile[MAXPATHLEN];
90*766Scarlsonj
91*766Scarlsonj (void) snprintf(mapfile, sizeof (mapfile), "%s/" PATH_MAPFILE,
92*766Scarlsonj rootpath);
93*766Scarlsonj
94*766Scarlsonj flags = O_RDWR | O_NOFOLLOW | O_NOLINKS;
95*766Scarlsonj if (createfile)
96*766Scarlsonj flags |= O_EXCL | O_CREAT;
97*766Scarlsonj if ((fd = open(mapfile, flags, 0644)) == -1) {
98*766Scarlsonj if (!createfile) {
99*766Scarlsonj errno = ENOENT;
100*766Scarlsonj goto failure;
101*766Scarlsonj }
102*766Scarlsonj if (lstat(mapfile, &lbuf) == -1)
103*766Scarlsonj goto failure;
104*766Scarlsonj if (!S_ISREG(lbuf.st_mode) || lbuf.st_nlink != 1 ||
105*766Scarlsonj lbuf.st_uid != 0) {
106*766Scarlsonj errno = EINVAL;
107*766Scarlsonj goto failure;
108*766Scarlsonj }
109*766Scarlsonj fd = open(mapfile, O_RDWR);
110*766Scarlsonj if (fd == -1)
111*766Scarlsonj goto failure;
112*766Scarlsonj if (fstat(fd, &fbuf) == -1)
113*766Scarlsonj goto failure;
114*766Scarlsonj if (lbuf.st_ino != fbuf.st_ino || lbuf.st_dev != fbuf.st_dev) {
115*766Scarlsonj errno = EINVAL;
116*766Scarlsonj goto failure;
117*766Scarlsonj }
118*766Scarlsonj }
119*766Scarlsonj if (lock_op(fd, F_RDLCK) == -1)
120*766Scarlsonj goto failure;
121*766Scarlsonj (void) umask(oldmask);
122*766Scarlsonj if ((fp = fdopen(fd, "r+")) == NULL)
123*766Scarlsonj (void) close(fd);
124*766Scarlsonj return (fp);
125*766Scarlsonj
126*766Scarlsonj failure:
127*766Scarlsonj if (fd != -1)
128*766Scarlsonj (void) close(fd);
129*766Scarlsonj (void) umask(oldmask);
130*766Scarlsonj return (NULL);
131*766Scarlsonj }
132*766Scarlsonj
133*766Scarlsonj int
zonecfg_lock_scratch(FILE * fp)134*766Scarlsonj zonecfg_lock_scratch(FILE *fp)
135*766Scarlsonj {
136*766Scarlsonj if (fflush(fp) != 0)
137*766Scarlsonj return (-1);
138*766Scarlsonj return (lock_op(fileno(fp), F_WRLCK));
139*766Scarlsonj }
140*766Scarlsonj
141*766Scarlsonj void
zonecfg_close_scratch(FILE * fp)142*766Scarlsonj zonecfg_close_scratch(FILE *fp)
143*766Scarlsonj {
144*766Scarlsonj (void) fclose(fp);
145*766Scarlsonj }
146*766Scarlsonj
147*766Scarlsonj int
zonecfg_get_scratch(FILE * fp,char * zonename,size_t namelen,char * kernname,size_t kernlen,char * altroot,size_t altlen)148*766Scarlsonj zonecfg_get_scratch(FILE *fp, char *zonename, size_t namelen, char *kernname,
149*766Scarlsonj size_t kernlen, char *altroot, size_t altlen)
150*766Scarlsonj {
151*766Scarlsonj char line[2 * ZONENAME_MAX + MAXPATHLEN + 2];
152*766Scarlsonj char *cp, *cp2;
153*766Scarlsonj
154*766Scarlsonj /* We always hold at least a read lock on the file */
155*766Scarlsonj for (;;) {
156*766Scarlsonj if (fgets(line, sizeof (line), fp) == NULL)
157*766Scarlsonj return (-1);
158*766Scarlsonj if ((cp = strchr(line, '\n')) == NULL)
159*766Scarlsonj return (-1);
160*766Scarlsonj *cp = '\0';
161*766Scarlsonj if ((cp = strchr(line, ' ')) == NULL)
162*766Scarlsonj cp = line + strlen(line);
163*766Scarlsonj else
164*766Scarlsonj *cp++ = '\0';
165*766Scarlsonj if (zonename != NULL &&
166*766Scarlsonj strlcpy(zonename, line, namelen) >= namelen)
167*766Scarlsonj continue;
168*766Scarlsonj if ((cp2 = strchr(cp, ' ')) == NULL)
169*766Scarlsonj cp2 = cp + strlen(cp);
170*766Scarlsonj else
171*766Scarlsonj *cp2++ = '\0';
172*766Scarlsonj if (kernname != NULL &&
173*766Scarlsonj strlcpy(kernname, cp, kernlen) >= kernlen)
174*766Scarlsonj continue;
175*766Scarlsonj if (altroot != NULL && strlcpy(altroot, cp2, altlen) >= altlen)
176*766Scarlsonj continue;
177*766Scarlsonj break;
178*766Scarlsonj }
179*766Scarlsonj return (0);
180*766Scarlsonj }
181*766Scarlsonj
182*766Scarlsonj int
zonecfg_find_scratch(FILE * fp,const char * zonename,const char * altroot,char * kernzone,size_t kernlen)183*766Scarlsonj zonecfg_find_scratch(FILE *fp, const char *zonename, const char *altroot,
184*766Scarlsonj char *kernzone, size_t kernlen)
185*766Scarlsonj {
186*766Scarlsonj char zone[ZONENAME_MAX];
187*766Scarlsonj char aroot[MAXPATHLEN];
188*766Scarlsonj
189*766Scarlsonj rewind(fp);
190*766Scarlsonj while (zonecfg_get_scratch(fp, zone, sizeof (zone), kernzone, kernlen,
191*766Scarlsonj aroot, sizeof (aroot)) == 0) {
192*766Scarlsonj if (strcmp(zone, zonename) == 0 && strcmp(altroot, aroot) == 0)
193*766Scarlsonj return (0);
194*766Scarlsonj }
195*766Scarlsonj return (-1);
196*766Scarlsonj }
197*766Scarlsonj
198*766Scarlsonj int
zonecfg_reverse_scratch(FILE * fp,const char * kernzone,char * zonename,size_t namelen,char * altroot,size_t altlen)199*766Scarlsonj zonecfg_reverse_scratch(FILE *fp, const char *kernzone, char *zonename,
200*766Scarlsonj size_t namelen, char *altroot, size_t altlen)
201*766Scarlsonj {
202*766Scarlsonj char kzone[ZONENAME_MAX];
203*766Scarlsonj
204*766Scarlsonj rewind(fp);
205*766Scarlsonj while (zonecfg_get_scratch(fp, zonename, namelen, kzone,
206*766Scarlsonj sizeof (kzone), altroot, altlen) == 0) {
207*766Scarlsonj if (strcmp(kzone, kernzone) == 0)
208*766Scarlsonj return (0);
209*766Scarlsonj }
210*766Scarlsonj return (-1);
211*766Scarlsonj }
212*766Scarlsonj
213*766Scarlsonj int
zonecfg_add_scratch(FILE * fp,const char * zonename,const char * kernzone,const char * altroot)214*766Scarlsonj zonecfg_add_scratch(FILE *fp, const char *zonename, const char *kernzone,
215*766Scarlsonj const char *altroot)
216*766Scarlsonj {
217*766Scarlsonj if (fseek(fp, 0, SEEK_END) == -1)
218*766Scarlsonj return (-1);
219*766Scarlsonj if (fprintf(fp, "%s %s %s\n", zonename, kernzone, altroot) == EOF)
220*766Scarlsonj return (-1);
221*766Scarlsonj if (fflush(fp) != 0)
222*766Scarlsonj return (-1);
223*766Scarlsonj return (0);
224*766Scarlsonj }
225*766Scarlsonj
226*766Scarlsonj int
zonecfg_delete_scratch(FILE * fp,const char * kernzone)227*766Scarlsonj zonecfg_delete_scratch(FILE *fp, const char *kernzone)
228*766Scarlsonj {
229*766Scarlsonj char zone[ZONENAME_MAX];
230*766Scarlsonj char kzone[ZONENAME_MAX];
231*766Scarlsonj char aroot[MAXPATHLEN];
232*766Scarlsonj long roffs, woffs;
233*766Scarlsonj
234*766Scarlsonj /*
235*766Scarlsonj * The implementation here is intentionally quite simple. We could
236*766Scarlsonj * allocate a buffer that's big enough to hold the data up to
237*766Scarlsonj * stat.st_size and then write back out the part we need to, but there
238*766Scarlsonj * seems to be little point.
239*766Scarlsonj */
240*766Scarlsonj rewind(fp);
241*766Scarlsonj roffs = 0;
242*766Scarlsonj do {
243*766Scarlsonj woffs = roffs;
244*766Scarlsonj if (zonecfg_get_scratch(fp, NULL, 0, kzone, sizeof (kzone),
245*766Scarlsonj NULL, 0) != 0)
246*766Scarlsonj return (-1);
247*766Scarlsonj roffs = ftell(fp);
248*766Scarlsonj } while (strcmp(kzone, kernzone) != 0);
249*766Scarlsonj while (zonecfg_get_scratch(fp, zone, sizeof (zone), kzone,
250*766Scarlsonj sizeof (kzone), aroot, sizeof aroot) == 0) {
251*766Scarlsonj roffs = ftell(fp);
252*766Scarlsonj if (fseek(fp, woffs, SEEK_SET) == -1)
253*766Scarlsonj break;
254*766Scarlsonj if (fprintf(fp, "%s %s %s\n", zone, kzone, aroot) == EOF)
255*766Scarlsonj break;
256*766Scarlsonj woffs = ftell(fp);
257*766Scarlsonj if (fseek(fp, roffs, SEEK_SET) == -1)
258*766Scarlsonj break;
259*766Scarlsonj }
260*766Scarlsonj (void) ftruncate(fileno(fp), woffs);
261*766Scarlsonj return (0);
262*766Scarlsonj }
263*766Scarlsonj
264*766Scarlsonj boolean_t
zonecfg_is_scratch(const char * kernzone)265*766Scarlsonj zonecfg_is_scratch(const char *kernzone)
266*766Scarlsonj {
267*766Scarlsonj return (strncmp(kernzone, "SUNWlu", 6) == 0);
268*766Scarlsonj }
269