Commit | Line | Data |
---|---|---|
0f78b815 WD |
1 | /* |
2 | * Support rsync daemon authentication. | |
3 | * | |
4 | * Copyright (C) 1998-2000 Andrew Tridgell | |
b3bf9b9d | 5 | * Copyright (C) 2002-2009 Wayne Davison |
0f78b815 WD |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify | |
8e41b68e WD |
8 | * it under the terms of the GNU General Public License as published by |
9 | * the Free Software Foundation; either version 3 of the License, or | |
10 | * (at your option) any later version. | |
0f78b815 WD |
11 | * |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | * | |
e7c67065 | 17 | * You should have received a copy of the GNU General Public License along |
4fd842f9 | 18 | * with this program; if not, visit the http://fsf.org website. |
0f78b815 | 19 | */ |
18cc8c7e | 20 | |
31593dd6 | 21 | #include "rsync.h" |
5ebe9a46 | 22 | #include "itypes.h" |
31593dd6 | 23 | |
5ebe9a46 | 24 | extern int read_only; |
38cab94d | 25 | extern char *password_file; |
38cab94d | 26 | |
bcb7e502 AT |
27 | /*************************************************************************** |
28 | encode a buffer using base64 - simple and slow algorithm. null terminates | |
29 | the result. | |
30 | ***************************************************************************/ | |
4a19c3b2 | 31 | void base64_encode(const char *buf, int len, char *out, int pad) |
bcb7e502 AT |
32 | { |
33 | char *b64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; | |
34 | int bit_offset, byte_offset, idx, i; | |
4a19c3b2 | 35 | const uchar *d = (const uchar *)buf; |
bcb7e502 AT |
36 | int bytes = (len*8 + 5)/6; |
37 | ||
57385128 | 38 | for (i = 0; i < bytes; i++) { |
bcb7e502 AT |
39 | byte_offset = (i*6)/8; |
40 | bit_offset = (i*6)%8; | |
41 | if (bit_offset < 3) { | |
42 | idx = (d[byte_offset] >> (2-bit_offset)) & 0x3F; | |
43 | } else { | |
44 | idx = (d[byte_offset] << (bit_offset-2)) & 0x3F; | |
45 | if (byte_offset+1 < len) { | |
46 | idx |= (d[byte_offset+1] >> (8-(bit_offset-2))); | |
47 | } | |
48 | } | |
49 | out[i] = b64[idx]; | |
50 | } | |
293def60 WD |
51 | |
52 | while (pad && (i % 4)) | |
53 | out[i++] = '='; | |
54 | ||
55 | out[i] = '\0'; | |
bcb7e502 AT |
56 | } |
57 | ||
bf011fed | 58 | /* Generate a challenge buffer and return it base64-encoded. */ |
4a19c3b2 | 59 | static void gen_challenge(const char *addr, char *challenge) |
bcb7e502 AT |
60 | { |
61 | char input[32]; | |
a0456b9c | 62 | char digest[MAX_DIGEST_LEN]; |
bcb7e502 | 63 | struct timeval tv; |
a0456b9c | 64 | int len; |
bcb7e502 | 65 | |
58c9b4b7 | 66 | memset(input, 0, sizeof input); |
bcb7e502 | 67 | |
4a19c3b2 | 68 | strlcpy(input, addr, 17); |
3060d4aa | 69 | sys_gettimeofday(&tv); |
bcb7e502 AT |
70 | SIVAL(input, 16, tv.tv_sec); |
71 | SIVAL(input, 20, tv.tv_usec); | |
72 | SIVAL(input, 24, getpid()); | |
73 | ||
ba582f75 | 74 | sum_init(0); |
58c9b4b7 | 75 | sum_update(input, sizeof input); |
a0456b9c | 76 | len = sum_end(digest); |
bf011fed | 77 | |
a0456b9c | 78 | base64_encode(digest, len, challenge, 0); |
bcb7e502 AT |
79 | } |
80 | ||
5ebe9a46 WD |
81 | /* Generate an MD4 hash created from the combination of the password |
82 | * and the challenge string and return it base64-encoded. */ | |
83 | static void generate_hash(const char *in, const char *challenge, char *out) | |
84 | { | |
85 | char buf[MAX_DIGEST_LEN]; | |
86 | int len; | |
87 | ||
88 | sum_init(0); | |
89 | sum_update(in, strlen(in)); | |
90 | sum_update(challenge, strlen(challenge)); | |
91 | len = sum_end(buf); | |
92 | ||
93 | base64_encode(buf, len, out, 0); | |
94 | } | |
bcb7e502 | 95 | |
38cab94d WD |
96 | /* Return the secret for a user from the secret file, null terminated. |
97 | * Maximum length is len (not counting the null). */ | |
5ebe9a46 WD |
98 | static const char *check_secret(int module, const char *user, const char *group, |
99 | const char *challenge, const char *pass) | |
bcb7e502 | 100 | { |
5ebe9a46 WD |
101 | char line[1024]; |
102 | char pass2[MAX_DIGEST_LEN*2]; | |
4a19c3b2 | 103 | const char *fname = lp_secrets_file(module); |
d1be2312 | 104 | STRUCT_STAT st; |
38cab94d | 105 | int fd, ok = 1; |
5ebe9a46 WD |
106 | int user_len = strlen(user); |
107 | int group_len = group ? strlen(group) : 0; | |
108 | char *err; | |
bcb7e502 | 109 | |
5ebe9a46 WD |
110 | if (!fname || !*fname || (fd = open(fname, O_RDONLY)) < 0) |
111 | return "no secrets file"; | |
bcb7e502 | 112 | |
5ebe9a46 WD |
113 | if (do_fstat(fd, &st) == -1) { |
114 | rsyserr(FLOG, errno, "fstat(%s)", fname); | |
d1be2312 | 115 | ok = 0; |
3ca8e68f DD |
116 | } else if (lp_strict_modes(module)) { |
117 | if ((st.st_mode & 06) != 0) { | |
30c041f9 | 118 | rprintf(FLOG, "secrets file must not be other-accessible (see strict modes option)\n"); |
3ca8e68f | 119 | ok = 0; |
351f5e2f | 120 | } else if (MY_UID() == 0 && st.st_uid != 0) { |
30c041f9 | 121 | rprintf(FLOG, "secrets file must be owned by root when running as root (see strict modes)\n"); |
3ca8e68f DD |
122 | ok = 0; |
123 | } | |
d1be2312 DD |
124 | } |
125 | if (!ok) { | |
d1be2312 | 126 | close(fd); |
5ebe9a46 | 127 | return "ignoring secrets file"; |
d1be2312 DD |
128 | } |
129 | ||
38cab94d WD |
130 | if (*user == '#') { |
131 | /* Reject attempt to match a comment. */ | |
132 | close(fd); | |
5ebe9a46 | 133 | return "invalid username"; |
38cab94d WD |
134 | } |
135 | ||
5ebe9a46 WD |
136 | /* Try to find a line that starts with the user (or @group) name and a ':'. */ |
137 | err = "secret not found"; | |
138 | while ((user || group) && read_line_old(fd, line, sizeof line, 1)) { | |
139 | const char **ptr, *s; | |
140 | int len; | |
141 | if (*line == '@') { | |
142 | ptr = &group; | |
143 | len = group_len; | |
144 | s = line+1; | |
145 | } else { | |
146 | ptr = &user; | |
147 | len = user_len; | |
148 | s = line; | |
38cab94d | 149 | } |
5ebe9a46 WD |
150 | if (!*ptr || strncmp(s, *ptr, len) != 0 || s[len] != ':') |
151 | continue; | |
152 | generate_hash(s+len+1, challenge, pass2); | |
153 | if (strcmp(pass, pass2) == 0) { | |
154 | err = NULL; | |
155 | break; | |
bcb7e502 | 156 | } |
5ebe9a46 WD |
157 | err = "password mismatch"; |
158 | *ptr = NULL; /* Don't look for name again. */ | |
bcb7e502 AT |
159 | } |
160 | ||
161 | close(fd); | |
bcb7e502 | 162 | |
5ebe9a46 WD |
163 | memset(line, 0, sizeof line); |
164 | memset(pass2, 0, sizeof pass2); | |
165 | ||
166 | return err; | |
bcb7e502 AT |
167 | } |
168 | ||
4a19c3b2 | 169 | static const char *getpassf(const char *filename) |
65575e96 | 170 | { |
65575e96 | 171 | STRUCT_STAT st; |
38cab94d WD |
172 | char buffer[512], *p; |
173 | int fd, n, ok = 1; | |
4a19c3b2 | 174 | const char *envpw = getenv("RSYNC_PASSWORD"); |
65575e96 | 175 | |
38cab94d WD |
176 | if (!filename) |
177 | return NULL; | |
65575e96 | 178 | |
38cab94d | 179 | if ((fd = open(filename,O_RDONLY)) < 0) { |
3f0211b6 | 180 | rsyserr(FWARNING, errno, "could not open password file \"%s\"", |
45c49b52 | 181 | filename); |
38cab94d | 182 | if (envpw) |
3f655ca0 | 183 | rprintf(FINFO, "falling back to RSYNC_PASSWORD environment variable.\n"); |
65575e96 AT |
184 | return NULL; |
185 | } | |
18cc8c7e | 186 | |
65575e96 | 187 | if (do_stat(filename, &st) == -1) { |
3f0211b6 | 188 | rsyserr(FWARNING, errno, "stat(%s)", filename); |
65575e96 AT |
189 | ok = 0; |
190 | } else if ((st.st_mode & 06) != 0) { | |
3f0211b6 | 191 | rprintf(FWARNING, "password file must not be other-accessible\n"); |
65575e96 | 192 | ok = 0; |
351f5e2f | 193 | } else if (MY_UID() == 0 && st.st_uid != 0) { |
3f0211b6 | 194 | rprintf(FWARNING, "password file must be owned by root when running as root\n"); |
65575e96 AT |
195 | ok = 0; |
196 | } | |
197 | if (!ok) { | |
65575e96 | 198 | close(fd); |
3f0211b6 | 199 | rprintf(FWARNING, "continuing without password file\n"); |
3f655ca0 WD |
200 | if (envpw) |
201 | rprintf(FINFO, "falling back to RSYNC_PASSWORD environment variable.\n"); | |
65575e96 AT |
202 | return NULL; |
203 | } | |
204 | ||
38cab94d WD |
205 | n = read(fd, buffer, sizeof buffer - 1); |
206 | close(fd); | |
207 | if (n > 0) { | |
208 | buffer[n] = '\0'; | |
209 | if ((p = strtok(buffer, "\n\r")) != NULL) | |
210 | return strdup(p); | |
18cc8c7e | 211 | } |
65575e96 AT |
212 | |
213 | return NULL; | |
214 | } | |
215 | ||
18cc8c7e WD |
216 | /* Possibly negotiate authentication with the client. Use "leader" to |
217 | * start off the auth if necessary. | |
218 | * | |
219 | * Return NULL if authentication failed. Return "" if anonymous access. | |
220 | * Otherwise return username. | |
221 | */ | |
4a19c3b2 WD |
222 | char *auth_server(int f_in, int f_out, int module, const char *host, |
223 | const char *addr, const char *leader) | |
bcb7e502 AT |
224 | { |
225 | char *users = lp_auth_users(module); | |
a0456b9c | 226 | char challenge[MAX_DIGEST_LEN*2]; |
d999d312 | 227 | char line[BIGPATHBUFLEN]; |
5ebe9a46 WD |
228 | char **auth_uid_groups = NULL; |
229 | int auth_uid_groups_cnt = -1; | |
230 | const char *err = NULL; | |
231 | int group_match = -1; | |
5037cf3a | 232 | char *tok, *pass; |
5ebe9a46 | 233 | char opt_ch = '\0'; |
bcb7e502 AT |
234 | |
235 | /* if no auth list then allow anyone in! */ | |
58c9b4b7 WD |
236 | if (!users || !*users) |
237 | return ""; | |
bcb7e502 AT |
238 | |
239 | gen_challenge(addr, challenge); | |
18cc8c7e | 240 | |
bf011fed | 241 | io_printf(f_out, "%s%s\n", leader, challenge); |
bcb7e502 | 242 | |
5ebe9a46 | 243 | if (!read_line_old(f_in, line, sizeof line, 0) |
5037cf3a WD |
244 | || (pass = strchr(line, ' ')) == NULL) { |
245 | rprintf(FLOG, "auth failed on module %s from %s (%s): " | |
246 | "invalid challenge response\n", | |
247 | lp_name(module), host, addr); | |
d0d56395 | 248 | return NULL; |
5037cf3a WD |
249 | } |
250 | *pass++ = '\0'; | |
18cc8c7e | 251 | |
5037cf3a WD |
252 | if (!(users = strdup(users))) |
253 | out_of_memory("auth_server"); | |
c8e78d87 | 254 | |
5037cf3a | 255 | for (tok = strtok(users, " ,\t"); tok; tok = strtok(NULL, " ,\t")) { |
5ebe9a46 WD |
256 | char *opts; |
257 | /* See if the user appended :deny, :ro, or :rw. */ | |
258 | if ((opts = strchr(tok, ':')) != NULL) { | |
259 | *opts++ = '\0'; | |
260 | opt_ch = isUpper(opts) ? toLower(opts) : *opts; | |
261 | if (opt_ch == 'r') { /* handle ro and rw */ | |
262 | opt_ch = isUpper(opts+1) ? toLower(opts+1) : opts[1]; | |
263 | if (opt_ch == 'o') | |
264 | opt_ch = 'r'; | |
265 | else if (opt_ch != 'w') | |
266 | opt_ch = '\0'; | |
267 | } else if (opt_ch != 'd') /* if it's not deny, ignore it */ | |
268 | opt_ch = '\0'; | |
269 | } else | |
270 | opt_ch = '\0'; | |
271 | if (*tok != '@') { | |
272 | /* Match the username */ | |
273 | if (wildmatch(tok, line)) | |
274 | break; | |
275 | } else { | |
276 | #ifdef HAVE_GETGROUPLIST | |
277 | int j; | |
278 | /* See if authorizing user is a real user, and if so, see | |
279 | * if it is in a group that matches tok+1 wildmat. */ | |
280 | if (auth_uid_groups_cnt < 0) { | |
281 | gid_t gid_list[64]; | |
282 | uid_t auth_uid; | |
283 | auth_uid_groups_cnt = sizeof gid_list / sizeof (gid_t); | |
284 | if (!user_to_uid(line, &auth_uid, False) | |
285 | || getallgroups(auth_uid, gid_list, &auth_uid_groups_cnt) != NULL) | |
286 | auth_uid_groups_cnt = 0; | |
287 | else { | |
288 | if ((auth_uid_groups = new_array(char *, auth_uid_groups_cnt)) == NULL) | |
289 | out_of_memory("auth_server"); | |
290 | for (j = 0; j < auth_uid_groups_cnt; j++) | |
291 | auth_uid_groups[j] = gid_to_group(gid_list[j]); | |
292 | } | |
293 | } | |
294 | for (j = 0; j < auth_uid_groups_cnt; j++) { | |
295 | if (auth_uid_groups[j] && wildmatch(tok+1, auth_uid_groups[j])) { | |
296 | group_match = j; | |
297 | break; | |
298 | } | |
299 | } | |
300 | if (group_match >= 0) | |
301 | break; | |
302 | #else | |
303 | rprintf(FLOG, "your computer doesn't support getgrouplist(), so no @group authorization is possible.\n"); | |
304 | #endif | |
305 | } | |
c8e78d87 | 306 | } |
5ebe9a46 | 307 | |
c8e78d87 AT |
308 | free(users); |
309 | ||
5ebe9a46 WD |
310 | if (!tok) |
311 | err = "no matching rule"; | |
312 | else if (opt_ch == 'd') | |
313 | err = "denied by rule"; | |
314 | else { | |
315 | char *group = group_match >= 0 ? auth_uid_groups[group_match] : NULL; | |
316 | err = check_secret(module, line, group, challenge, pass); | |
5037cf3a | 317 | } |
18cc8c7e | 318 | |
5ebe9a46 WD |
319 | memset(challenge, 0, sizeof challenge); |
320 | memset(pass, 0, strlen(pass)); | |
bcb7e502 | 321 | |
5ebe9a46 WD |
322 | if (auth_uid_groups) { |
323 | int j; | |
324 | for (j = 0; j < auth_uid_groups_cnt; j++) { | |
325 | if (auth_uid_groups[j]) | |
326 | free(auth_uid_groups[j]); | |
327 | } | |
328 | free(auth_uid_groups); | |
329 | } | |
18cc8c7e | 330 | |
5ebe9a46 WD |
331 | if (err) { |
332 | rprintf(FLOG, "auth failed on module %s from %s (%s) for %s: %s\n", | |
333 | lp_name(module), host, addr, line, err); | |
5037cf3a WD |
334 | return NULL; |
335 | } | |
d0d56395 | 336 | |
5ebe9a46 WD |
337 | if (opt_ch == 'r') |
338 | read_only = 1; | |
339 | else if (opt_ch == 'w') | |
340 | read_only = 0; | |
341 | ||
5037cf3a | 342 | return strdup(line); |
bcb7e502 AT |
343 | } |
344 | ||
4a19c3b2 | 345 | void auth_client(int fd, const char *user, const char *challenge) |
bcb7e502 | 346 | { |
4a19c3b2 | 347 | const char *pass; |
a0456b9c | 348 | char pass2[MAX_DIGEST_LEN*2]; |
bcb7e502 | 349 | |
ef383c0d | 350 | if (!user || !*user) |
4b2f6a7c | 351 | user = "nobody"; |
bcb7e502 | 352 | |
58c9b4b7 WD |
353 | if (!(pass = getpassf(password_file)) |
354 | && !(pass = getenv("RSYNC_PASSWORD"))) { | |
64bd7568 | 355 | /* XXX: cyeoh says that getpass is deprecated, because |
908f5a9f MP |
356 | * it may return a truncated password on some systems, |
357 | * and it is not in the LSB. | |
358 | * | |
359 | * Andrew Klein says that getpassphrase() is present | |
360 | * on Solaris and reads up to 256 characters. | |
361 | * | |
362 | * OpenBSD has a readpassphrase() that might be more suitable. | |
363 | */ | |
bcb7e502 AT |
364 | pass = getpass("Password: "); |
365 | } | |
366 | ||
38cab94d | 367 | if (!pass) |
bcb7e502 | 368 | pass = ""; |
bcb7e502 AT |
369 | |
370 | generate_hash(pass, challenge, pass2); | |
bcb7e502 AT |
371 | io_printf(fd, "%s %s\n", user, pass2); |
372 | } |