Improve the noise collection for the internal random pool.
[sgt/putty] / unix / uxstore.c
1 /*
2 * uxstore.c: Unix-specific implementation of the interface defined
3 * in storage.h.
4 */
5
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <ctype.h>
9 #include <unistd.h>
10 #include <fcntl.h>
11 #include <sys/stat.h>
12 #include <sys/types.h>
13 #include "putty.h"
14 #include "storage.h"
15 #include "tree234.h"
16
17 /*
18 * For the moment, the only existing Unix utility is pterm and that
19 * has no GUI configuration at all, so our write routines need do
20 * nothing. Eventually I suppose these will read and write an rc
21 * file somewhere or other.
22 */
23
24 void *open_settings_w(char *sessionname)
25 {
26 return NULL;
27 }
28
29 void write_setting_s(void *handle, char *key, char *value)
30 {
31 }
32
33 void write_setting_i(void *handle, char *key, int value)
34 {
35 }
36
37 void close_settings_w(void *handle)
38 {
39 }
40
41 /*
42 * Reading settings, for the moment, is done by retrieving X
43 * resources from the X display. When we introduce disk files, I
44 * think what will happen is that the X resources will override
45 * PuTTY's inbuilt defaults, but that the disk files will then
46 * override those. This isn't optimal, but it's the best I can
47 * immediately work out.
48 */
49
50 struct xrm_string {
51 char *key;
52 char *value;
53 };
54
55 static tree234 *xrmtree = NULL;
56
57 int xrmcmp(void *av, void *bv)
58 {
59 struct xrm_string *a = (struct xrm_string *)av;
60 struct xrm_string *b = (struct xrm_string *)bv;
61 return strcmp(a->key, b->key);
62 }
63
64 void provide_xrm_string(char *string)
65 {
66 char *p, *q;
67 struct xrm_string *xrms, *ret;
68
69 p = q = strchr(string, ':');
70 if (!q) {
71 fprintf(stderr, "pterm: expected a colon in resource string"
72 " \"%s\"\n", string);
73 return;
74 }
75 q++;
76 while (p > string && p[-1] != '.' && p[-1] != '*')
77 p--;
78 xrms = smalloc(sizeof(struct xrm_string));
79 xrms->key = smalloc(q-p);
80 memcpy(xrms->key, p, q-p);
81 xrms->key[q-p-1] = '\0';
82 while (*q && isspace(*q))
83 q++;
84 xrms->value = dupstr(q);
85
86 if (!xrmtree)
87 xrmtree = newtree234(xrmcmp);
88
89 ret = add234(xrmtree, xrms);
90 if (ret) {
91 /* Override an existing string. */
92 del234(xrmtree, ret);
93 add234(xrmtree, xrms);
94 }
95 }
96
97 char *get_setting(char *key)
98 {
99 struct xrm_string tmp, *ret;
100 tmp.key = key;
101 if (xrmtree) {
102 ret = find234(xrmtree, &tmp, NULL);
103 if (ret)
104 return ret->value;
105 }
106 return x_get_default(key);
107 }
108
109 void *open_settings_r(char *sessionname)
110 {
111 static int thing_to_return_an_arbitrary_non_null_pointer_to;
112 return &thing_to_return_an_arbitrary_non_null_pointer_to;
113 }
114
115 char *read_setting_s(void *handle, char *key, char *buffer, int buflen)
116 {
117 char *val = get_setting(key);
118 if (!val)
119 return NULL;
120 else {
121 strncpy(buffer, val, buflen);
122 buffer[buflen-1] = '\0';
123 return buffer;
124 }
125 }
126
127 int read_setting_i(void *handle, char *key, int defvalue)
128 {
129 char *val = get_setting(key);
130 if (!val)
131 return defvalue;
132 else
133 return atoi(val);
134 }
135
136 void close_settings_r(void *handle)
137 {
138 }
139
140 void del_settings(char *sessionname)
141 {
142 }
143
144 void *enum_settings_start(void)
145 {
146 return NULL;
147 }
148
149 char *enum_settings_next(void *handle, char *buffer, int buflen)
150 {
151 return NULL;
152 }
153
154 void enum_settings_finish(void *handle)
155 {
156 }
157
158 enum {
159 INDEX_DIR, INDEX_HOSTKEYS, INDEX_RANDSEED
160 };
161
162 static void make_filename(char *filename, int index)
163 {
164 char *home;
165 int len;
166 home = getenv("HOME");
167 strncpy(filename, home, FILENAME_MAX);
168 len = strlen(filename);
169 strncpy(filename + len,
170 index == INDEX_DIR ? "/.putty" :
171 index == INDEX_HOSTKEYS ? "/.putty/sshhostkeys" :
172 index == INDEX_RANDSEED ? "/.putty/randomseed" :
173 "/.putty/ERROR", FILENAME_MAX - len);
174 filename[FILENAME_MAX-1] = '\0';
175 }
176
177 /*
178 * Read an entire line of text from a file. Return a buffer
179 * malloced to be as big as necessary (caller must free).
180 */
181 static char *fgetline(FILE *fp)
182 {
183 char *ret = smalloc(512);
184 int size = 512, len = 0;
185 while (fgets(ret + len, size - len, fp)) {
186 len += strlen(ret + len);
187 if (ret[len-1] == '\n')
188 break; /* got a newline, we're done */
189 size = len + 512;
190 ret = srealloc(ret, size);
191 }
192 if (len == 0) { /* first fgets returned NULL */
193 sfree(ret);
194 return NULL;
195 }
196 ret[len] = '\0';
197 return ret;
198 }
199
200 /*
201 * Lines in the host keys file are of the form
202 *
203 * type@port:hostname keydata
204 *
205 * e.g.
206 *
207 * rsa@22:foovax.example.org 0x23,0x293487364395345345....2343
208 */
209 int verify_host_key(char *hostname, int port, char *keytype, char *key)
210 {
211 FILE *fp;
212 char filename[FILENAME_MAX];
213 char *line;
214 int ret;
215
216 make_filename(filename, INDEX_HOSTKEYS);
217 fp = fopen(filename, "r");
218 if (!fp)
219 return 1; /* key does not exist */
220
221 ret = 1;
222 while ( (line = fgetline(fp)) ) {
223 int i;
224 char *p = line;
225 char porttext[20];
226
227 line[strcspn(line, "\n")] = '\0'; /* strip trailing newline */
228
229 i = strlen(keytype);
230 if (strncmp(p, keytype, i))
231 goto done;
232 p += i;
233
234 if (*p != '@')
235 goto done;
236 p++;
237
238 sprintf(porttext, "%d", port);
239 i = strlen(porttext);
240 if (strncmp(p, porttext, i))
241 goto done;
242 p += i;
243
244 if (*p != ':')
245 goto done;
246 p++;
247
248 i = strlen(hostname);
249 if (strncmp(p, hostname, i))
250 goto done;
251 p += i;
252
253 if (*p != ' ')
254 goto done;
255 p++;
256
257 /*
258 * Found the key. Now just work out whether it's the right
259 * one or not.
260 */
261 if (!strcmp(p, key))
262 ret = 0; /* key matched OK */
263 else
264 ret = 2; /* key mismatch */
265
266 done:
267 sfree(line);
268 if (ret != 1)
269 break;
270 }
271
272 return ret;
273 }
274
275 void store_host_key(char *hostname, int port, char *keytype, char *key)
276 {
277 FILE *fp;
278 int fd;
279 char filename[FILENAME_MAX];
280
281 make_filename(filename, INDEX_HOSTKEYS);
282 fd = open(filename, O_CREAT | O_APPEND | O_RDWR, 0600);
283 if (fd < 0) {
284 char dir[FILENAME_MAX];
285
286 make_filename(dir, INDEX_DIR);
287 mkdir(dir, 0700);
288 fd = open(filename, O_CREAT | O_APPEND | O_RDWR, 0600);
289 }
290 if (fd < 0) {
291 perror(filename);
292 exit(1);
293 }
294 fp = fdopen(fd, "a");
295 fprintf(fp, "%s@%d:%s %s\n", keytype, port, hostname, key);
296 fclose(fp);
297 }
298
299 void read_random_seed(noise_consumer_t consumer)
300 {
301 int fd;
302 char fname[FILENAME_MAX];
303
304 make_filename(fname, INDEX_RANDSEED);
305 fd = open(fname, O_RDONLY);
306 if (fd) {
307 char buf[512];
308 int ret;
309 while ( (ret = read(fd, buf, sizeof(buf))) > 0)
310 consumer(buf, ret);
311 close(fd);
312 }
313 }
314
315 void write_random_seed(void *data, int len)
316 {
317 int fd;
318 char fname[FILENAME_MAX];
319
320 make_filename(fname, INDEX_RANDSEED);
321 fd = open(fname, O_CREAT | O_TRUNC | O_WRONLY, 0600);
322 if (fd < 0) {
323 char dir[FILENAME_MAX];
324
325 make_filename(dir, INDEX_DIR);
326 mkdir(dir, 0700);
327 fd = open(fname, O_CREAT | O_TRUNC | O_WRONLY, 0600);
328 }
329
330 while (len > 0) {
331 int ret = write(fd, data, len);
332 if (ret <= 0) break;
333 len -= ret;
334 data = (char *)data + len;
335 }
336
337 close(fd);
338 }
339
340 void cleanup_all(void)
341 {
342 }