| 1 | This patch adds the ability to do group authentications to the "auth users" |
| 2 | line via the @group idiom and to specify a group password via an @group entry |
| 3 | in the secrets file (though the latter is not required if you wish to have |
| 4 | per-user passwords). It also allows you to override a module's read-only or |
| 5 | read-write setting on a per auth-entry basis by adding a :ro or :rw suffix to a |
| 6 | username or a @groupname. |
| 7 | |
| 8 | To use this patch, run these commands for a successful build: |
| 9 | |
| 10 | patch -p1 <patches/group-auth.diff |
| 11 | ./configure (optional if already run) |
| 12 | make |
| 13 | |
| 14 | based-on: a01e3b490eb36ccf9e704840e1b6683dab867550 |
| 15 | diff --git a/authenticate.c b/authenticate.c |
| 16 | --- a/authenticate.c |
| 17 | +++ b/authenticate.c |
| 18 | @@ -19,7 +19,9 @@ |
| 19 | */ |
| 20 | |
| 21 | #include "rsync.h" |
| 22 | +#include "itypes.h" |
| 23 | |
| 24 | +extern int read_only; |
| 25 | extern char *password_file; |
| 26 | |
| 27 | /*************************************************************************** |
| 28 | @@ -76,25 +78,40 @@ static void gen_challenge(const char *addr, char *challenge) |
| 29 | base64_encode(digest, len, challenge, 0); |
| 30 | } |
| 31 | |
| 32 | +/* Generate an MD4 hash created from the combination of the password |
| 33 | + * and the challenge string and return it base64-encoded. */ |
| 34 | +static void generate_hash(const char *in, const char *challenge, char *out) |
| 35 | +{ |
| 36 | + char buf[MAX_DIGEST_LEN]; |
| 37 | + int len; |
| 38 | + |
| 39 | + sum_init(0); |
| 40 | + sum_update(in, strlen(in)); |
| 41 | + sum_update(challenge, strlen(challenge)); |
| 42 | + len = sum_end(buf); |
| 43 | + |
| 44 | + base64_encode(buf, len, out, 0); |
| 45 | +} |
| 46 | |
| 47 | /* Return the secret for a user from the secret file, null terminated. |
| 48 | * Maximum length is len (not counting the null). */ |
| 49 | -static int get_secret(int module, const char *user, char *secret, int len) |
| 50 | +static const char *check_secret(int module, const char *user, const char *group, |
| 51 | + const char *challenge, const char *pass) |
| 52 | { |
| 53 | + char line[1024]; |
| 54 | + char pass2[MAX_DIGEST_LEN*2]; |
| 55 | const char *fname = lp_secrets_file(module); |
| 56 | STRUCT_STAT st; |
| 57 | int fd, ok = 1; |
| 58 | - const char *p; |
| 59 | - char ch, *s; |
| 60 | + int user_len = strlen(user); |
| 61 | + int group_len = group ? strlen(group) : 0; |
| 62 | + char *err; |
| 63 | |
| 64 | - if (!fname || !*fname) |
| 65 | - return 0; |
| 66 | + if (!fname || !*fname || (fd = open(fname, O_RDONLY)) < 0) |
| 67 | + return "no secrets file"; |
| 68 | |
| 69 | - if ((fd = open(fname, O_RDONLY)) < 0) |
| 70 | - return 0; |
| 71 | - |
| 72 | - if (do_stat(fname, &st) == -1) { |
| 73 | - rsyserr(FLOG, errno, "stat(%s)", fname); |
| 74 | + if (do_fstat(fd, &st) == -1) { |
| 75 | + rsyserr(FLOG, errno, "fstat(%s)", fname); |
| 76 | ok = 0; |
| 77 | } else if (lp_strict_modes(module)) { |
| 78 | if ((st.st_mode & 06) != 0) { |
| 79 | @@ -106,50 +123,47 @@ static int get_secret(int module, const char *user, char *secret, int len) |
| 80 | } |
| 81 | } |
| 82 | if (!ok) { |
| 83 | - rprintf(FLOG, "continuing without secrets file\n"); |
| 84 | close(fd); |
| 85 | - return 0; |
| 86 | + return "ignoring secrets file"; |
| 87 | } |
| 88 | |
| 89 | if (*user == '#') { |
| 90 | /* Reject attempt to match a comment. */ |
| 91 | close(fd); |
| 92 | - return 0; |
| 93 | + return "invalid username"; |
| 94 | } |
| 95 | |
| 96 | - /* Try to find a line that starts with the user name and a ':'. */ |
| 97 | - p = user; |
| 98 | - while (1) { |
| 99 | - if (read(fd, &ch, 1) != 1) { |
| 100 | - close(fd); |
| 101 | - return 0; |
| 102 | + /* Try to find a line that starts with the user (or @group) name and a ':'. */ |
| 103 | + err = "secret not found"; |
| 104 | + while ((user || group) && read_line_old(fd, line, sizeof line)) { |
| 105 | + const char **ptr, *s; |
| 106 | + int len; |
| 107 | + if (*line == '@') { |
| 108 | + ptr = &group; |
| 109 | + len = group_len; |
| 110 | + s = line+1; |
| 111 | + } else { |
| 112 | + ptr = &user; |
| 113 | + len = user_len; |
| 114 | + s = line; |
| 115 | } |
| 116 | - if (ch == '\n') |
| 117 | - p = user; |
| 118 | - else if (p) { |
| 119 | - if (*p == ch) |
| 120 | - p++; |
| 121 | - else if (!*p && ch == ':') |
| 122 | - break; |
| 123 | - else |
| 124 | - p = NULL; |
| 125 | + if (!*ptr || strncmp(s, *ptr, len) != 0 || s[len] != ':') |
| 126 | + continue; |
| 127 | + generate_hash(s+len+1, challenge, pass2); |
| 128 | + if (strcmp(pass, pass2) == 0) { |
| 129 | + err = NULL; |
| 130 | + break; |
| 131 | } |
| 132 | + err = "password mismatch"; |
| 133 | + *ptr = NULL; /* Don't look for name again. */ |
| 134 | } |
| 135 | |
| 136 | - /* Slurp the secret into the "secret" buffer. */ |
| 137 | - s = secret; |
| 138 | - while (len > 0) { |
| 139 | - if (read(fd, s, 1) != 1 || *s == '\n') |
| 140 | - break; |
| 141 | - if (*s == '\r') |
| 142 | - continue; |
| 143 | - s++; |
| 144 | - len--; |
| 145 | - } |
| 146 | - *s = '\0'; |
| 147 | close(fd); |
| 148 | |
| 149 | - return 1; |
| 150 | + memset(line, 0, sizeof line); |
| 151 | + memset(pass2, 0, sizeof pass2); |
| 152 | + |
| 153 | + return err; |
| 154 | } |
| 155 | |
| 156 | static const char *getpassf(const char *filename) |
| 157 | @@ -199,21 +213,6 @@ static const char *getpassf(const char *filename) |
| 158 | return NULL; |
| 159 | } |
| 160 | |
| 161 | -/* Generate an MD4 hash created from the combination of the password |
| 162 | - * and the challenge string and return it base64-encoded. */ |
| 163 | -static void generate_hash(const char *in, const char *challenge, char *out) |
| 164 | -{ |
| 165 | - char buf[MAX_DIGEST_LEN]; |
| 166 | - int len; |
| 167 | - |
| 168 | - sum_init(0); |
| 169 | - sum_update(in, strlen(in)); |
| 170 | - sum_update(challenge, strlen(challenge)); |
| 171 | - len = sum_end(buf); |
| 172 | - |
| 173 | - base64_encode(buf, len, out, 0); |
| 174 | -} |
| 175 | - |
| 176 | /* Possibly negotiate authentication with the client. Use "leader" to |
| 177 | * start off the auth if necessary. |
| 178 | * |
| 179 | @@ -226,9 +225,12 @@ char *auth_server(int f_in, int f_out, int module, const char *host, |
| 180 | char *users = lp_auth_users(module); |
| 181 | char challenge[MAX_DIGEST_LEN*2]; |
| 182 | char line[BIGPATHBUFLEN]; |
| 183 | - char secret[512]; |
| 184 | - char pass2[MAX_DIGEST_LEN*2]; |
| 185 | + char **auth_uid_groups = NULL; |
| 186 | + int auth_uid_groups_cnt = -1; |
| 187 | + const char *err = NULL; |
| 188 | + int group_match = -1; |
| 189 | char *tok, *pass; |
| 190 | + char opt_ch = '\0'; |
| 191 | |
| 192 | /* if no auth list then allow anyone in! */ |
| 193 | if (!users || !*users) |
| 194 | @@ -251,37 +253,92 @@ char *auth_server(int f_in, int f_out, int module, const char *host, |
| 195 | out_of_memory("auth_server"); |
| 196 | |
| 197 | for (tok = strtok(users, " ,\t"); tok; tok = strtok(NULL, " ,\t")) { |
| 198 | - if (wildmatch(tok, line)) |
| 199 | - break; |
| 200 | + char *opts; |
| 201 | + /* See if the user appended :deny, :ro, or :rw. */ |
| 202 | + if ((opts = strchr(tok, ':')) != NULL) { |
| 203 | + *opts++ = '\0'; |
| 204 | + opt_ch = isUpper(opts) ? toLower(opts) : *opts; |
| 205 | + if (opt_ch == 'r') { /* handle ro and rw */ |
| 206 | + opt_ch = isUpper(opts+1) ? toLower(opts+1) : opts[1]; |
| 207 | + if (opt_ch == 'o') |
| 208 | + opt_ch = 'r'; |
| 209 | + else if (opt_ch != 'w') |
| 210 | + opt_ch = '\0'; |
| 211 | + } else if (opt_ch != 'd') /* if it's not deny, ignore it */ |
| 212 | + opt_ch = '\0'; |
| 213 | + } else |
| 214 | + opt_ch = '\0'; |
| 215 | + if (*tok != '@') { |
| 216 | + /* Match the username */ |
| 217 | + if (wildmatch(tok, line)) |
| 218 | + break; |
| 219 | + } else { |
| 220 | +#ifdef HAVE_GETGROUPLIST |
| 221 | + int j; |
| 222 | + /* See if authorizing user is a real user, and if so, see |
| 223 | + * if it is in a group that matches tok+1 wildmat. */ |
| 224 | + if (auth_uid_groups_cnt < 0) { |
| 225 | + gid_t gid_list[64]; |
| 226 | + uid_t auth_uid; |
| 227 | + auth_uid_groups_cnt = sizeof gid_list / sizeof (gid_t); |
| 228 | + if (!user_to_uid(line, &auth_uid, False) |
| 229 | + || getallgroups(auth_uid, gid_list, &auth_uid_groups_cnt) != NULL) |
| 230 | + auth_uid_groups_cnt = 0; |
| 231 | + else { |
| 232 | + if ((auth_uid_groups = new_array(char *, auth_uid_groups_cnt)) == NULL) |
| 233 | + out_of_memory("auth_server"); |
| 234 | + for (j = 0; j < auth_uid_groups_cnt; j++) |
| 235 | + auth_uid_groups[j] = gid_to_group(gid_list[j]); |
| 236 | + } |
| 237 | + } |
| 238 | + for (j = 0; j < auth_uid_groups_cnt; j++) { |
| 239 | + if (auth_uid_groups[j] && wildmatch(tok+1, auth_uid_groups[j])) { |
| 240 | + group_match = j; |
| 241 | + break; |
| 242 | + } |
| 243 | + } |
| 244 | + if (group_match >= 0) |
| 245 | + break; |
| 246 | +#else |
| 247 | + rprintf(FLOG, "your computer doesn't support getgrouplist(), so no @group authorization is possible.\n"); |
| 248 | +#endif |
| 249 | + } |
| 250 | } |
| 251 | + |
| 252 | free(users); |
| 253 | |
| 254 | - if (!tok) { |
| 255 | - rprintf(FLOG, "auth failed on module %s from %s (%s): " |
| 256 | - "unauthorized user\n", |
| 257 | - lp_name(module), host, addr); |
| 258 | - return NULL; |
| 259 | + if (!tok) |
| 260 | + err = "no matching rule"; |
| 261 | + else if (opt_ch == 'd') |
| 262 | + err = "denied by rule"; |
| 263 | + else { |
| 264 | + char *group = group_match >= 0 ? auth_uid_groups[group_match] : NULL; |
| 265 | + err = check_secret(module, line, group, challenge, pass); |
| 266 | } |
| 267 | |
| 268 | - memset(secret, 0, sizeof secret); |
| 269 | - if (!get_secret(module, line, secret, sizeof secret - 1)) { |
| 270 | - memset(secret, 0, sizeof secret); |
| 271 | - rprintf(FLOG, "auth failed on module %s from %s (%s): " |
| 272 | - "missing secret for user \"%s\"\n", |
| 273 | - lp_name(module), host, addr, line); |
| 274 | - return NULL; |
| 275 | - } |
| 276 | + memset(challenge, 0, sizeof challenge); |
| 277 | + memset(pass, 0, strlen(pass)); |
| 278 | |
| 279 | - generate_hash(secret, challenge, pass2); |
| 280 | - memset(secret, 0, sizeof secret); |
| 281 | + if (auth_uid_groups) { |
| 282 | + int j; |
| 283 | + for (j = 0; j < auth_uid_groups_cnt; j++) { |
| 284 | + if (auth_uid_groups[j]) |
| 285 | + free(auth_uid_groups[j]); |
| 286 | + } |
| 287 | + free(auth_uid_groups); |
| 288 | + } |
| 289 | |
| 290 | - if (strcmp(pass, pass2) != 0) { |
| 291 | - rprintf(FLOG, "auth failed on module %s from %s (%s): " |
| 292 | - "password mismatch\n", |
| 293 | - lp_name(module), host, addr); |
| 294 | + if (err) { |
| 295 | + rprintf(FLOG, "auth failed on module %s from %s (%s) for %s: %s\n", |
| 296 | + lp_name(module), host, addr, line, err); |
| 297 | return NULL; |
| 298 | } |
| 299 | |
| 300 | + if (opt_ch == 'r') |
| 301 | + read_only = 1; |
| 302 | + else if (opt_ch == 'w') |
| 303 | + read_only = 0; |
| 304 | + |
| 305 | return strdup(line); |
| 306 | } |
| 307 | |
| 308 | diff --git a/clientserver.c b/clientserver.c |
| 309 | --- a/clientserver.c |
| 310 | +++ b/clientserver.c |
| 311 | @@ -545,6 +545,7 @@ static int rsync_module(int f_in, int f_out, int i, const char *addr, const char |
| 312 | return -1; |
| 313 | } |
| 314 | |
| 315 | + read_only = lp_read_only(i); /* may also be overridden by auth_server() */ |
| 316 | auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD "); |
| 317 | |
| 318 | if (!auth_user) { |
| 319 | @@ -555,9 +556,6 @@ static int rsync_module(int f_in, int f_out, int i, const char *addr, const char |
| 320 | |
| 321 | module_id = i; |
| 322 | |
| 323 | - if (lp_read_only(i)) |
| 324 | - read_only = 1; |
| 325 | - |
| 326 | if (lp_transfer_logging(i) && !logfile_format) |
| 327 | logfile_format = lp_log_format(i); |
| 328 | if (log_format_has(logfile_format, 'i')) |
| 329 | diff --git a/rsyncd.conf.yo b/rsyncd.conf.yo |
| 330 | --- a/rsyncd.conf.yo |
| 331 | +++ b/rsyncd.conf.yo |
| 332 | @@ -318,6 +318,8 @@ attempted uploads will fail. If "read only" is false then uploads will |
| 333 | be possible if file permissions on the daemon side allow them. The default |
| 334 | is for all modules to be read only. |
| 335 | |
| 336 | +Note that "auth users" can override this setting on a per-user basis. |
| 337 | + |
| 338 | dit(bf(write only)) This parameter determines whether clients |
| 339 | will be able to download files or not. If "write only" is true then any |
| 340 | attempted downloads will fail. If "write only" is false then downloads |
| 341 | @@ -430,10 +432,12 @@ be on to the clients. |
| 342 | See the description of the bf(--chmod) rsync option and the bf(chmod)(1) |
| 343 | manpage for information on the format of this string. |
| 344 | |
| 345 | -dit(bf(auth users)) This parameter specifies a comma and |
| 346 | -space-separated list of usernames that will be allowed to connect to |
| 347 | +dit(bf(auth users)) This parameter specifies a comma and/or space-separated |
| 348 | +list of authorization rules. In its simplest form, you list the usernames |
| 349 | +that will be allowed to connect to |
| 350 | this module. The usernames do not need to exist on the local |
| 351 | -system. The usernames may also contain shell wildcard characters. If |
| 352 | +system. The rules may contain shell wildcard characters that will be matched |
| 353 | +against the username provided by the client for authentication. If |
| 354 | "auth users" is set then the client will be challenged to supply a |
| 355 | username and password to connect to the module. A challenge response |
| 356 | authentication protocol is used for this exchange. The plain text |
| 357 | @@ -441,20 +445,50 @@ usernames and passwords are stored in the file specified by the |
| 358 | "secrets file" parameter. The default is for all users to be able to |
| 359 | connect without a password (this is called "anonymous rsync"). |
| 360 | |
| 361 | +In addition to username matching, you can specify groupname matching via a '@' |
| 362 | +prefix. When using groupname matching, the authenticating username must be a |
| 363 | +real user on the system, or it will be assumed to be a member of no groups. |
| 364 | +For example, specifying "@rsync" will match the authenticating user if the |
| 365 | +named user is a member of the rsync group. |
| 366 | + |
| 367 | +Finally, options may be specified after a colon (:). The options allow you to |
| 368 | +"deny" a user or a group, set the access to "ro" (read-only), or set the access |
| 369 | +to "rw" (read/write). Setting an auth-rule-specific ro/rw setting overrides |
| 370 | +the module's default "read only" setting. |
| 371 | + |
| 372 | +Be sure to put the rules in the order you want them to be matched, because the |
| 373 | +checking stops at the first match. For example: |
| 374 | + |
| 375 | +verb( auth users = joe:deny @guest:deny admin:rw @rsync:ro susan ) |
| 376 | + |
| 377 | +In the above rule, user joe will be denied access no matter what. Any user |
| 378 | +that is in the group "guest" is also denied access. The user "admin" gets |
| 379 | +access in read/write mode, even if the admin user is in group rsync (because |
| 380 | +the admin user-matching rule is before the rsync group-matching rule). |
| 381 | +Finally, user susan gets the default ro/rw setting of the module, but only |
| 382 | +if susan's user didn't match an earlier group-matching rule. |
| 383 | + |
| 384 | +See the description of the secrets file for how you can have per-user passwords |
| 385 | +as well as per-group passwords (either or both). |
| 386 | + |
| 387 | See also the section entitled "USING RSYNC-DAEMON FEATURES VIA A REMOTE |
| 388 | SHELL CONNECTION" in bf(rsync)(1) for information on how handle an |
| 389 | rsyncd.conf-level username that differs from the remote-shell-level |
| 390 | username when using a remote shell to connect to an rsync daemon. |
| 391 | |
| 392 | -dit(bf(secrets file)) This parameter specifies the name of |
| 393 | -a file that contains the username:password pairs used for |
| 394 | -authenticating this module. This file is only consulted if the "auth |
| 395 | -users" parameter is specified. The file is line based and contains |
| 396 | -username:password pairs separated by a single colon. Any line starting |
| 397 | -with a hash (#) is considered a comment and is skipped. The passwords |
| 398 | -can contain any characters but be warned that many operating systems |
| 399 | -limit the length of passwords that can be typed at the client end, so |
| 400 | -you may find that passwords longer than 8 characters don't work. |
| 401 | +dit(bf(secrets file)) This parameter specifies the name of a file that contains |
| 402 | +the username:password and/or @group:password pairs used for authenticating this |
| 403 | +module. This file is only consulted if the "auth users" parameter is specified. |
| 404 | +The file is line-based and contains one name:password pair per line. Any line |
| 405 | +has a hash (#) as the very first character on the line is considered a comment |
| 406 | +and is skipped. The passwords can contain any characters but be warned that |
| 407 | +many operating systems limit the length of passwords that can be typed at the |
| 408 | +client end, so you may find that passwords longer than 8 characters don't work. |
| 409 | + |
| 410 | +The use of group-specific lines are only relevant when the module was |
| 411 | +authorized using a matching "@group" rule. When that happens, the user can be |
| 412 | +authorized via either their "username:password" line or the "@group:password" |
| 413 | +line for the group that triggered the authentication. |
| 414 | |
| 415 | There is no default for the "secrets file" parameter, you must choose a name |
| 416 | (such as tt(/etc/rsyncd.secrets)). The file must normally not be readable |