xref: /plan9/sys/src/cmd/unix/drawterm/libauthsrv/readnvram.c (revision 8ccd4a6360d974db7bd7bbd4f37e7018419ea908)
1 #include <u.h>
2 #include <libc.h>
3 #include <authsrv.h>
4 
5 static long	finddosfile(int, char*);
6 
7 static int
check(void * x,int len,uchar sum,char * msg)8 check(void *x, int len, uchar sum, char *msg)
9 {
10 	if(nvcsum(x, len) == sum)
11 		return 0;
12 	memset(x, 0, len);
13 	fprint(2, "%s\n", msg);
14 	return 1;
15 }
16 
17 /*
18  *  get key info out of nvram.  since there isn't room in the PC's nvram use
19  *  a disk partition there.
20  */
21 static struct {
22 	char *cputype;
23 	char *file;
24 	int off;
25 	int len;
26 } nvtab[] = {
27 	"sparc", "#r/nvram", 1024+850, sizeof(Nvrsafe),
28 	"pc", "#S/sdC0/nvram", 0, sizeof(Nvrsafe),
29 	"pc", "#S/sdC0/9fat", -1, sizeof(Nvrsafe),
30 	"pc", "#S/sd00/nvram", 0, sizeof(Nvrsafe),
31 	"pc", "#S/sd00/9fat", -1, sizeof(Nvrsafe),
32 	"pc", "#S/sd01/nvram", 0, sizeof(Nvrsafe),
33 	"pc", "#S/sd01/9fat", -1, sizeof(Nvrsafe),
34 	"pc", "#f/fd0disk", -1, 512,	/* 512: #f requires whole sector reads */
35 	"pc", "#f/fd1disk", -1, 512,
36 	"mips", "#r/nvram", 1024+900, sizeof(Nvrsafe),
37 	"power", "#F/flash/flash0", 0x300000, sizeof(Nvrsafe),
38 	"power", "#r/nvram", 4352, sizeof(Nvrsafe),	/* OK for MTX-604e */
39 	"debug", "/tmp/nvram", 0, sizeof(Nvrsafe),
40 };
41 
42 static char*
readcons(char * prompt,char * def,int raw,char * buf,int nbuf)43 readcons(char *prompt, char *def, int raw, char *buf, int nbuf)
44 {
45 	int fdin, fdout, ctl, n, m;
46 	char line[10];
47 
48 	fdin = open("/dev/cons", OREAD);
49 	if(fdin < 0)
50 		fdin = 0;
51 	fdout = open("/dev/cons", OWRITE);
52 	if(fdout < 0)
53 		fdout = 1;
54 	if(def != nil)
55 		fprint(fdout, "%s[%s]: ", prompt, def);
56 	else
57 		fprint(fdout, "%s: ", prompt);
58 	if(raw){
59 		ctl = open("/dev/consctl", OWRITE);
60 		if(ctl >= 0)
61 			write(ctl, "rawon", 5);
62 	} else
63 		ctl = -1;
64 
65 	m = 0;
66 	for(;;){
67 		n = read(fdin, line, 1);
68 		if(n == 0){
69 			close(ctl);
70 			werrstr("readcons: EOF");
71 			return nil;
72 		}
73 		if(n < 0){
74 			close(ctl);
75 			werrstr("can't read cons");
76 			return nil;
77 		}
78 		if(line[0] == 0x7f)
79 			exits(0);
80 		if(n == 0 || line[0] == '\n' || line[0] == '\r'){
81 			if(raw){
82 				write(ctl, "rawoff", 6);
83 				write(fdout, "\n", 1);
84 				close(ctl);
85 			}
86 			buf[m] = '\0';
87 			if(buf[0]=='\0' && def)
88 				strcpy(buf, def);
89 			return buf;
90 		}
91 		if(line[0] == '\b'){
92 			if(m > 0)
93 				m--;
94 		}else if(line[0] == 0x15){	/* ^U: line kill */
95 			m = 0;
96 			if(def != nil)
97 				fprint(fdout, "%s[%s]: ", prompt, def);
98 			else
99 				fprint(fdout, "%s: ", prompt);
100 		}else{
101 			if(m >= nbuf-1){
102 				fprint(fdout, "line too long\n");
103 				m = 0;
104 				if(def != nil)
105 					fprint(fdout, "%s[%s]: ", prompt, def);
106 				else
107 					fprint(fdout, "%s: ", prompt);
108 			}else
109 				buf[m++] = line[0];
110 		}
111 	}
112 	return buf;	/* how does this happen */
113 }
114 
115 
116 /*
117  *  get key info out of nvram.  since there isn't room in the PC's nvram use
118  *  a disk partition there.
119  */
120 int
readnvram(Nvrsafe * safep,int flag)121 readnvram(Nvrsafe *safep, int flag)
122 {
123 	char buf[1024], in[128], *cputype, *nvrfile, *nvrlen, *nvroff, *v[2];
124 	int fd, err, i, safeoff, safelen;
125 	Nvrsafe *safe;
126 
127 	err = 0;
128 	memset(safep, 0, sizeof(*safep));
129 
130 	nvrfile = getenv("nvram");
131 	cputype = getenv("cputype");
132 	if(cputype == nil)
133 		cputype = "mips";
134 	if(strcmp(cputype, "386")==0 || strcmp(cputype, "alpha")==0)
135 		cputype = "pc";
136 
137 	safe = (Nvrsafe*)buf;
138 
139 	fd = -1;
140 	safeoff = -1;
141 	safelen = -1;
142 	if(nvrfile != nil){
143 		/* accept device and device!file */
144 		i = gettokens(nvrfile, v, nelem(v), "!");
145 		fd = open(v[0], ORDWR);
146 		safelen = sizeof(Nvrsafe);
147 		if(strstr(v[0], "/9fat") == nil)
148 			safeoff = 0;
149 		nvrlen = getenv("nvrlen");
150 		if(nvrlen != nil)
151 			safelen = atoi(nvrlen);
152 		nvroff = getenv("nvroff");
153 		if(nvroff != nil){
154 			if(strcmp(nvroff, "dos") == 0)
155 				safeoff = -1;
156 			else
157 				safeoff = atoi(nvroff);
158 		}
159 		if(safeoff < 0 && fd >= 0){
160 			safelen = 512;
161 			safeoff = finddosfile(fd, i == 2 ? v[1] : "plan9.nvr");
162 			if(safeoff < 0){
163 				close(fd);
164 				fd = -1;
165 			}
166 		}
167 		free(nvrfile);
168 		if(nvrlen != nil)
169 			free(nvrlen);
170 		if(nvroff != nil)
171 			free(nvroff);
172 	}else{
173 		for(i=0; i<nelem(nvtab); i++){
174 			if(strcmp(cputype, nvtab[i].cputype) != 0)
175 				continue;
176 			if((fd = open(nvtab[i].file, ORDWR)) < 0)
177 				continue;
178 			safeoff = nvtab[i].off;
179 			safelen = nvtab[i].len;
180 			if(safeoff == -1){
181 				safeoff = finddosfile(fd, "plan9.nvr");
182 				if(safeoff < 0){
183 					close(fd);
184 					fd = -1;
185 					continue;
186 				}
187 			}
188 			break;
189 		}
190 	}
191 
192 	if(fd < 0
193 	|| seek(fd, safeoff, 0) < 0
194 	|| read(fd, buf, safelen) != safelen){
195 		err = 1;
196 		if(flag&(NVwrite|NVwriteonerr))
197 			fprint(2, "can't read nvram: %r\n");
198 		memset(safep, 0, sizeof(*safep));
199 		safe = safep;
200 	}else{
201 		*safep = *safe;
202 		safe = safep;
203 
204 		err |= check(safe->machkey, DESKEYLEN, safe->machsum, "bad nvram key");
205 //		err |= check(safe->config, CONFIGLEN, safe->configsum, "bad secstore key");
206 		err |= check(safe->authid, ANAMELEN, safe->authidsum, "bad authentication id");
207 		err |= check(safe->authdom, DOMLEN, safe->authdomsum, "bad authentication domain");
208 	}
209 
210 	if((flag&NVwrite) || (err && (flag&NVwriteonerr))){
211 		readcons("authid", nil, 0, safe->authid, sizeof(safe->authid));
212 		readcons("authdom", nil, 0, safe->authdom, sizeof(safe->authdom));
213 		readcons("secstore key", nil, 1, safe->config, sizeof(safe->config));
214 		for(;;){
215 			if(readcons("password", nil, 1, in, sizeof in) == nil)
216 				goto Out;
217 			if(passtokey(safe->machkey, in))
218 				break;
219 		}
220 		safe->machsum = nvcsum(safe->machkey, DESKEYLEN);
221 		safe->configsum = nvcsum(safe->config, CONFIGLEN);
222 		safe->authidsum = nvcsum(safe->authid, sizeof(safe->authid));
223 		safe->authdomsum = nvcsum(safe->authdom, sizeof(safe->authdom));
224 		*(Nvrsafe*)buf = *safe;
225 		if(seek(fd, safeoff, 0) < 0
226 		|| write(fd, buf, safelen) != safelen){
227 			fprint(2, "can't write key to nvram: %r\n");
228 			err = 1;
229 		}else
230 			err = 0;
231 	}
232 Out:
233 	close(fd);
234 	return err ? -1 : 0;
235 }
236 
237 typedef struct Dosboot	Dosboot;
238 struct Dosboot{
239 	uchar	magic[3];	/* really an xx86 JMP instruction */
240 	uchar	version[8];
241 	uchar	sectsize[2];
242 	uchar	clustsize;
243 	uchar	nresrv[2];
244 	uchar	nfats;
245 	uchar	rootsize[2];
246 	uchar	volsize[2];
247 	uchar	mediadesc;
248 	uchar	fatsize[2];
249 	uchar	trksize[2];
250 	uchar	nheads[2];
251 	uchar	nhidden[4];
252 	uchar	bigvolsize[4];
253 	uchar	driveno;
254 	uchar	reserved0;
255 	uchar	bootsig;
256 	uchar	volid[4];
257 	uchar	label[11];
258 	uchar	type[8];
259 };
260 #define	GETSHORT(p) (((p)[1]<<8) | (p)[0])
261 #define	GETLONG(p) ((GETSHORT((p)+2) << 16) | GETSHORT((p)))
262 
263 typedef struct Dosdir	Dosdir;
264 struct Dosdir
265 {
266 	char	name[8];
267 	char	ext[3];
268 	uchar	attr;
269 	uchar	reserved[10];
270 	uchar	time[2];
271 	uchar	date[2];
272 	uchar	start[2];
273 	uchar	length[4];
274 };
275 
276 static char*
dosparse(char * from,char * to,int len)277 dosparse(char *from, char *to, int len)
278 {
279 	char c;
280 
281 	memset(to, ' ', len);
282 	if(from == 0)
283 		return 0;
284 	while(len-- > 0){
285 		c = *from++;
286 		if(c == '.')
287 			return from;
288 		if(c == 0)
289 			break;
290 		if(c >= 'a' && c <= 'z')
291 			*to++ = c + 'A' - 'a';
292 		else
293 			*to++ = c;
294 	}
295 	return 0;
296 }
297 
298 /*
299  *  return offset of first file block
300  *
301  *  This is a very simplistic dos file system.  It only
302  *  works on floppies, only looks in the root, and only
303  *  returns a pointer to the first block of a file.
304  *
305  *  This exists for cpu servers that have no hard disk
306  *  or nvram to store the key on.
307  *
308  *  Please don't make this any smarter: it stays resident
309  *  and I'ld prefer not to waste the space on something that
310  *  runs only at boottime -- presotto.
311  */
312 static long
finddosfile(int fd,char * file)313 finddosfile(int fd, char *file)
314 {
315 	uchar secbuf[512];
316 	char name[8];
317 	char ext[3];
318 	Dosboot	*b;
319 	Dosdir *root, *dp;
320 	int nroot, sectsize, rootoff, rootsects, n;
321 
322 	/* dos'ize file name */
323 	file = dosparse(file, name, 8);
324 	dosparse(file, ext, 3);
325 
326 	/* read boot block, check for sanity */
327 	b = (Dosboot*)secbuf;
328 	if(read(fd, secbuf, sizeof(secbuf)) != sizeof(secbuf))
329 		return -1;
330 	if(b->magic[0] != 0xEB || b->magic[1] != 0x3C || b->magic[2] != 0x90)
331 		return -1;
332 	sectsize = GETSHORT(b->sectsize);
333 	if(sectsize != 512)
334 		return -1;
335 	rootoff = (GETSHORT(b->nresrv) + b->nfats*GETSHORT(b->fatsize)) * sectsize;
336 	if(seek(fd, rootoff, 0) < 0)
337 		return -1;
338 	nroot = GETSHORT(b->rootsize);
339 	rootsects = (nroot*sizeof(Dosdir)+sectsize-1)/sectsize;
340 	if(rootsects <= 0 || rootsects > 64)
341 		return -1;
342 
343 	/*
344 	 *  read root. it is contiguous to make stuff like
345 	 *  this easier
346 	 */
347 	root = malloc(rootsects*sectsize);
348 	if(read(fd, root, rootsects*sectsize) != rootsects*sectsize)
349 		return -1;
350 	n = -1;
351 	for(dp = root; dp < &root[nroot]; dp++)
352 		if(memcmp(name, dp->name, 8) == 0 && memcmp(ext, dp->ext, 3) == 0){
353 			n = GETSHORT(dp->start);
354 			break;
355 		}
356 	free(root);
357 
358 	if(n < 0)
359 		return -1;
360 
361 	/*
362 	 *  dp->start is in cluster units, not sectors.  The first
363 	 *  cluster is cluster 2 which starts immediately after the
364 	 *  root directory
365 	 */
366 	return rootoff + rootsects*sectsize + (n-2)*sectsize*b->clustsize;
367 }
368 
369