Commit | Line | Data |
---|---|---|
56c473b7 | 1 | /* |
0f78b815 WD |
2 | * Routines to authenticate access to a daemon (hosts allow/deny). |
3 | * | |
4 | * Copyright (C) 1998 Andrew Tridgell | |
b3bf9b9d | 5 | * Copyright (C) 2004-2009 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 | */ |
56c473b7 AT |
20 | |
21 | #include "rsync.h" | |
22 | ||
bf4170ad WD |
23 | static int allow_forward_dns; |
24 | ||
25 | extern const char undetermined_hostname[]; | |
26 | ||
27 | static int match_hostname(const char **host_ptr, const char *addr, const char *tok) | |
56c473b7 | 28 | { |
bf4170ad WD |
29 | struct hostent *hp; |
30 | unsigned int i; | |
31 | const char *host = *host_ptr; | |
32 | ||
36142821 WD |
33 | if (!host || !*host) |
34 | return 0; | |
bf4170ad WD |
35 | |
36 | /* First check if the reverse-DNS-determined hostname matches. */ | |
37 | if (iwildmatch(tok, host)) | |
38 | return 1; | |
39 | ||
40 | if (!allow_forward_dns) | |
41 | return 0; | |
42 | ||
43 | /* Fail quietly if tok is an address or wildcarded entry, not a simple hostname. */ | |
44 | if (!tok[strspn(tok, ".0123456789")] || tok[strcspn(tok, ":/*?[")]) | |
45 | return 0; | |
46 | ||
47 | /* Now try forward-DNS on the token (config-specified hostname) and see if the IP matches. */ | |
48 | if (!(hp = gethostbyname(tok))) | |
49 | return 0; | |
50 | ||
51 | for (i = 0; hp->h_addr_list[i] != NULL; i++) { | |
52 | if (strcmp(addr, inet_ntoa(*(struct in_addr*)(hp->h_addr_list[i]))) == 0) { | |
53 | /* If reverse lookups are off, we'll use the conf-specified | |
54 | * hostname in preference to UNDETERMINED. */ | |
55 | if (host == undetermined_hostname) { | |
56 | if (!(*host_ptr = strdup(tok))) | |
57 | *host_ptr = undetermined_hostname; | |
58 | } | |
59 | return 1; | |
60 | } | |
61 | } | |
62 | ||
63 | return 0; | |
56c473b7 AT |
64 | } |
65 | ||
df694f72 | 66 | static int match_binary(const char *b1, const char *b2, const char *mask, int addrlen) |
bc2b4963 DD |
67 | { |
68 | int i; | |
69 | ||
36142821 WD |
70 | for (i = 0; i < addrlen; i++) { |
71 | if ((b1[i] ^ b2[i]) & mask[i]) | |
bc2b4963 | 72 | return 0; |
bc2b4963 DD |
73 | } |
74 | ||
75 | return 1; | |
76 | } | |
77 | ||
36142821 WD |
78 | static void make_mask(char *mask, int plen, int addrlen) |
79 | { | |
bc2b4963 DD |
80 | int w, b; |
81 | ||
82 | w = plen >> 3; | |
83 | b = plen & 0x7; | |
84 | ||
85 | if (w) | |
86 | memset(mask, 0xff, w); | |
7bc8218d DD |
87 | if (w < addrlen) |
88 | mask[w] = 0xff & (0xff<<(8-b)); | |
bc2b4963 DD |
89 | if (w+1 < addrlen) |
90 | memset(mask+w+1, 0, addrlen-w-1); | |
91 | ||
92 | return; | |
93 | } | |
56c473b7 | 94 | |
df694f72 | 95 | static int match_address(const char *addr, const char *tok) |
56c473b7 AT |
96 | { |
97 | char *p; | |
bc2b4963 DD |
98 | struct addrinfo hints, *resa, *rest; |
99 | int gai; | |
100 | int ret = 0; | |
101 | int addrlen = 0; | |
4f5b0756 | 102 | #ifdef HAVE_STRTOL |
bc2b4963 DD |
103 | long int bits; |
104 | #else | |
105 | int bits; | |
106 | #endif | |
107 | char mask[16]; | |
108 | char *a = NULL, *t = NULL; | |
56c473b7 | 109 | |
36142821 WD |
110 | if (!addr || !*addr) |
111 | return 0; | |
56c473b7 | 112 | |
56c473b7 | 113 | p = strchr(tok,'/'); |
bf4170ad | 114 | if (p) |
32f60a6e | 115 | *p = '\0'; |
56c473b7 | 116 | |
bf4170ad WD |
117 | /* Fail quietly if tok is a hostname, not an address. */ |
118 | if (tok[strspn(tok, ".0123456789")] && strchr(tok, ':') == NULL) { | |
be7cf822 WD |
119 | if (p) |
120 | *p = '/'; | |
121 | return 0; | |
122 | } | |
70a6051c | 123 | |
bc2b4963 DD |
124 | memset(&hints, 0, sizeof(hints)); |
125 | hints.ai_family = PF_UNSPEC; | |
126 | hints.ai_socktype = SOCK_STREAM; | |
8d2aad49 | 127 | #ifdef AI_NUMERICHOST |
bc2b4963 | 128 | hints.ai_flags = AI_NUMERICHOST; |
8d2aad49 | 129 | #endif |
56c473b7 | 130 | |
be7cf822 WD |
131 | if (getaddrinfo(addr, NULL, &hints, &resa) != 0) { |
132 | if (p) | |
133 | *p = '/'; | |
134 | return 0; | |
135 | } | |
56c473b7 | 136 | |
bc2b4963 DD |
137 | gai = getaddrinfo(tok, NULL, &hints, &rest); |
138 | if (p) | |
139 | *p++ = '/'; | |
be7cf822 WD |
140 | if (gai != 0) { |
141 | rprintf(FLOG, "error matching address %s: %s\n", | |
142 | tok, gai_strerror(gai)); | |
bc2b4963 | 143 | freeaddrinfo(resa); |
56c473b7 AT |
144 | return 0; |
145 | } | |
146 | ||
bc2b4963 DD |
147 | if (rest->ai_family != resa->ai_family) { |
148 | ret = 0; | |
149 | goto out; | |
150 | } | |
151 | ||
152 | switch(resa->ai_family) { | |
153 | case PF_INET: | |
154 | a = (char *)&((struct sockaddr_in *)resa->ai_addr)->sin_addr; | |
155 | t = (char *)&((struct sockaddr_in *)rest->ai_addr)->sin_addr; | |
156 | addrlen = 4; | |
157 | ||
158 | break; | |
159 | ||
4f5b0756 | 160 | #ifdef INET6 |
bc2b4963 DD |
161 | case PF_INET6: |
162 | { | |
163 | struct sockaddr_in6 *sin6a, *sin6t; | |
56c473b7 | 164 | |
bc2b4963 DD |
165 | sin6a = (struct sockaddr_in6 *)resa->ai_addr; |
166 | sin6t = (struct sockaddr_in6 *)rest->ai_addr; | |
167 | ||
168 | a = (char *)&sin6a->sin6_addr; | |
169 | t = (char *)&sin6t->sin6_addr; | |
170 | ||
7bc8218d DD |
171 | addrlen = 16; |
172 | ||
4f5b0756 | 173 | #ifdef HAVE_SOCKADDR_IN6_SCOPE_ID |
bc2b4963 DD |
174 | if (sin6t->sin6_scope_id && |
175 | sin6a->sin6_scope_id != sin6t->sin6_scope_id) { | |
176 | ret = 0; | |
177 | goto out; | |
178 | } | |
179 | #endif | |
180 | ||
bc2b4963 DD |
181 | break; |
182 | } | |
183 | #endif | |
184 | default: | |
be7cf822 | 185 | rprintf(FLOG, "unknown family %u\n", rest->ai_family); |
bc2b4963 DD |
186 | ret = 0; |
187 | goto out; | |
188 | } | |
189 | ||
190 | bits = -1; | |
56c473b7 | 191 | if (p) { |
bc2b4963 | 192 | if (inet_pton(resa->ai_addr->sa_family, p, mask) <= 0) { |
4f5b0756 | 193 | #ifdef HAVE_STRTOL |
bc2b4963 DD |
194 | char *ep = NULL; |
195 | #else | |
196 | unsigned char *pp; | |
197 | #endif | |
198 | ||
4f5b0756 | 199 | #ifdef HAVE_STRTOL |
bc2b4963 DD |
200 | bits = strtol(p, &ep, 10); |
201 | if (!*p || *ep) { | |
be7cf822 | 202 | rprintf(FLOG, "malformed mask in %s\n", tok); |
bc2b4963 DD |
203 | ret = 0; |
204 | goto out; | |
205 | } | |
206 | #else | |
207 | for (pp = (unsigned char *)p; *pp; pp++) { | |
208 | if (!isascii(*pp) || !isdigit(*pp)) { | |
be7cf822 | 209 | rprintf(FLOG, "malformed mask in %s\n", tok); |
bc2b4963 DD |
210 | ret = 0; |
211 | goto out; | |
212 | } | |
56c473b7 | 213 | } |
bc2b4963 DD |
214 | bits = atoi(p); |
215 | #endif | |
216 | if (bits == 0) { | |
217 | ret = 1; | |
218 | goto out; | |
219 | } | |
220 | if (bits < 0 || bits > (addrlen << 3)) { | |
be7cf822 | 221 | rprintf(FLOG, "malformed mask in %s\n", tok); |
bc2b4963 DD |
222 | ret = 0; |
223 | goto out; | |
56c473b7 | 224 | } |
56c473b7 | 225 | } |
bc2b4963 DD |
226 | } else { |
227 | bits = 128; | |
56c473b7 AT |
228 | } |
229 | ||
bc2b4963 DD |
230 | if (bits >= 0) |
231 | make_mask(mask, bits, addrlen); | |
232 | ||
233 | ret = match_binary(a, t, mask, addrlen); | |
234 | ||
2997e9f7 | 235 | out: |
bc2b4963 DD |
236 | freeaddrinfo(resa); |
237 | freeaddrinfo(rest); | |
238 | return ret; | |
56c473b7 AT |
239 | } |
240 | ||
bf4170ad | 241 | static int access_match(const char *list, const char *addr, const char **host_ptr) |
56c473b7 AT |
242 | { |
243 | char *tok; | |
244 | char *list2 = strdup(list); | |
245 | ||
36142821 WD |
246 | if (!list2) |
247 | out_of_memory("access_match"); | |
56c473b7 | 248 | |
5a96ee05 | 249 | strlower(list2); |
5a96ee05 | 250 | |
36142821 | 251 | for (tok = strtok(list2, " ,\t"); tok; tok = strtok(NULL, " ,\t")) { |
bf4170ad | 252 | if (match_hostname(host_ptr, addr, tok) || match_address(addr, tok)) { |
56c473b7 AT |
253 | free(list2); |
254 | return 1; | |
255 | } | |
256 | } | |
257 | ||
258 | free(list2); | |
259 | return 0; | |
260 | } | |
261 | ||
bf4170ad | 262 | int allow_access(const char *addr, const char **host_ptr, int i) |
56c473b7 | 263 | { |
bf4170ad WD |
264 | const char *allow_list = lp_hosts_allow(i); |
265 | const char *deny_list = lp_hosts_deny(i); | |
266 | ||
36142821 WD |
267 | if (allow_list && !*allow_list) |
268 | allow_list = NULL; | |
269 | if (deny_list && !*deny_list) | |
270 | deny_list = NULL; | |
271 | ||
bf4170ad WD |
272 | allow_forward_dns = lp_forward_lookup(i); |
273 | ||
36142821 WD |
274 | /* If we match an allow-list item, we always allow access. */ |
275 | if (allow_list) { | |
bf4170ad | 276 | if (access_match(allow_list, addr, host_ptr)) |
36142821 WD |
277 | return 1; |
278 | /* For an allow-list w/o a deny-list, disallow non-matches. */ | |
279 | if (!deny_list) | |
280 | return 0; | |
281 | } | |
282 | ||
283 | /* If we match a deny-list item (and got past any allow-list | |
284 | * items), we always disallow access. */ | |
bf4170ad | 285 | if (deny_list && access_match(deny_list, addr, host_ptr)) |
56c473b7 AT |
286 | return 0; |
287 | ||
36142821 | 288 | /* Allow all other access. */ |
56c473b7 AT |
289 | return 1; |
290 | } |