1 /* $NetBSD: cleanup_masquerade.c,v 1.2 2017/02/14 01:16:44 christos Exp $ */
2
3 /*++
4 /* NAME
5 /* cleanup_masquerade 3
6 /* SUMMARY
7 /* address masquerading
8 /* SYNOPSIS
9 /* #include <cleanup.h>
10 /*
11 /* int cleanup_masquerade_external(addr, masq_domains)
12 /* VSTRING *addr;
13 /* ARGV *masq_domains;
14 /*
15 /* int cleanup_masquerade_internal(addr, masq_domains)
16 /* VSTRING *addr;
17 /* ARGV *masq_domains;
18 /*
19 /* int cleanup_masquerade_tree(tree, masq_domains)
20 /* TOK822 *tree;
21 /* ARGV *masq_domains;
22 /* DESCRIPTION
23 /* This module masquerades addresses, that is, it strips subdomains
24 /* below domain names that are listed in the masquerade_domains
25 /* configuration parameter, except for user names listed in the
26 /* masquerade_exceptions configuration parameter.
27 /* These functions return non-zero when the address was changed.
28 /*
29 /* cleanup_masquerade_external() rewrites the external (quoted) string
30 /* form of an address.
31 /*
32 /* cleanup_masquerade_internal() is a wrapper around the
33 /* cleanup_masquerade_external() routine that transforms from
34 /* internal (quoted) string form to external form and back.
35 /*
36 /* cleanup_masquerade_tree() is a wrapper around the
37 /* cleanup_masquerade_external() routine that transforms from
38 /* internal parse tree form to external form and back.
39 /* DIAGNOSTICS
40 /* LICENSE
41 /* .ad
42 /* .fi
43 /* The Secure Mailer license must be distributed with this software.
44 /* AUTHOR(S)
45 /* Wietse Venema
46 /* IBM T.J. Watson Research
47 /* P.O. Box 704
48 /* Yorktown Heights, NY 10598, USA
49 /*--*/
50
51 /* System library. */
52
53 #include <sys_defs.h>
54 #include <string.h>
55
56 /* Utility library. */
57
58 #include <msg.h>
59 #include <vstring.h>
60 #include <argv.h>
61 #include <htable.h>
62 #include <mymalloc.h>
63 #include <stringops.h>
64
65 /* Global library. */
66
67 #include <mail_params.h>
68 #include <tok822.h>
69 #include <quote_822_local.h>
70
71 /* Application-specific. */
72
73 #include "cleanup.h"
74
75 #define STR vstring_str
76
77 /* cleanup_masquerade_external - masquerade address external form */
78
cleanup_masquerade_external(CLEANUP_STATE * state,VSTRING * addr,ARGV * masq_domains)79 int cleanup_masquerade_external(CLEANUP_STATE *state, VSTRING *addr,
80 ARGV *masq_domains)
81 {
82 char *domain;
83 ssize_t domain_len;
84 char **masqp;
85 char *masq;
86 ssize_t masq_len;
87 char *parent;
88 int truncate;
89 int did_rewrite = 0;
90
91 /* Stuff for excluded names. */
92 char *name;
93 ssize_t name_len;
94 int excluded;
95
96 /*
97 * Find the domain part.
98 */
99 if ((domain = strrchr(STR(addr), '@')) == 0)
100 return (0);
101 name_len = domain - STR(addr);
102 domain = casefold(state->temp2, domain + 1);
103 domain_len = strlen(domain);
104
105 /*
106 * Don't masquerade excluded names (regardless of domain).
107 */
108 if (*var_masq_exceptions) {
109 name = mystrndup(STR(addr), name_len);
110 excluded = (string_list_match(cleanup_masq_exceptions, name) != 0);
111 myfree(name);
112 if (cleanup_masq_exceptions->error) {
113 msg_info("%s: %s map lookup problem -- "
114 "message not accepted, try again later",
115 state->queue_id, VAR_MASQ_EXCEPTIONS);
116 state->errs |= CLEANUP_STAT_WRITE;
117 }
118 if (excluded)
119 return (0);
120 }
121
122 /*
123 * If any parent domain matches the list of masquerade domains, replace
124 * the domain in the address and terminate. If the domain matches a
125 * masquerade domain, leave it alone. Order of specification matters.
126 */
127 for (masqp = masq_domains->argv; (masq = *masqp) != 0; masqp++) {
128 for (truncate = 1; *masq == '!'; masq++)
129 truncate = !truncate;
130 masq = casefold(state->temp1, masq);
131 masq_len = strlen(masq);
132 if (masq_len == 0)
133 continue;
134 if (masq_len == domain_len) {
135 if (strcmp(masq, domain) == 0)
136 break;
137 } else if (masq_len < domain_len) {
138 parent = domain + domain_len - masq_len;
139 if (parent[-1] == '.' && strcmp(masq, parent) == 0) {
140 if (truncate) {
141 if (msg_verbose)
142 msg_info("masquerade: %s -> %s", domain, masq);
143 vstring_truncate(addr, name_len + 1);
144 vstring_strcat(addr, masq);
145 did_rewrite = 1;
146 }
147 break;
148 }
149 }
150 }
151 return (did_rewrite);
152 }
153
154 /* cleanup_masquerade_tree - masquerade address node */
155
cleanup_masquerade_tree(CLEANUP_STATE * state,TOK822 * tree,ARGV * masq_domains)156 int cleanup_masquerade_tree(CLEANUP_STATE *state, TOK822 *tree,
157 ARGV *masq_domains)
158 {
159 VSTRING *temp = vstring_alloc(100);
160 int did_rewrite;
161
162 tok822_externalize(temp, tree->head, TOK822_STR_DEFL);
163 did_rewrite = cleanup_masquerade_external(state, temp, masq_domains);
164 tok822_free_tree(tree->head);
165 tree->head = tok822_scan(STR(temp), &tree->tail);
166
167 vstring_free(temp);
168 return (did_rewrite);
169 }
170
171 /* cleanup_masquerade_internal - masquerade address internal form */
172
cleanup_masquerade_internal(CLEANUP_STATE * state,VSTRING * addr,ARGV * masq_domains)173 int cleanup_masquerade_internal(CLEANUP_STATE *state, VSTRING *addr,
174 ARGV *masq_domains)
175 {
176 VSTRING *temp = vstring_alloc(100);
177 int did_rewrite;
178
179 quote_822_local(temp, STR(addr));
180 did_rewrite = cleanup_masquerade_external(state, temp, masq_domains);
181 unquote_822_local(addr, STR(temp));
182
183 vstring_free(temp);
184 return (did_rewrite);
185 }
186
187 /*
188 * Code for stand-alone testing. Instead of using main.cf, specify the strip
189 * list and the candidate domain on the command line. Specify null arguments
190 * for data that should be empty.
191 */
192 #ifdef TEST
193
194 #include <vstream.h>
195
196 char *var_masq_exceptions;
197 STRING_LIST *cleanup_masq_exceptions;
198
main(int argc,char ** argv)199 int main(int argc, char **argv)
200 {
201 VSTRING *addr;
202 ARGV *masq_domains;
203 CLEANUP_STATE state;
204
205 if (argc != 4)
206 msg_fatal("usage: %s exceptions masquerade_list address", argv[0]);
207
208 var_masq_exceptions = argv[1];
209 cleanup_masq_exceptions =
210 string_list_init(VAR_MASQ_EXCEPTIONS, MATCH_FLAG_RETURN,
211 var_masq_exceptions);
212 masq_domains = argv_split(argv[2], CHARS_COMMA_SP);
213 addr = vstring_alloc(1);
214 if (strchr(argv[3], '@') == 0)
215 msg_fatal("address must be in user@domain form");
216 vstring_strcpy(addr, argv[3]);
217
218 vstream_printf("----------\n");
219 vstream_printf("exceptions: %s\n", argv[1]);
220 vstream_printf("masq_list: %s\n", argv[2]);
221 vstream_printf("address: %s\n", argv[3]);
222
223 state.errs = 0;
224 state.queue_id = "NOQUEUE";
225 state.temp1 = vstring_alloc(100);
226 state.temp2 = vstring_alloc(100);
227 cleanup_masquerade_external(&state, addr, masq_domains);
228
229 vstream_printf("result: %s\n", STR(addr));
230 vstream_printf("errs: %d\n", state.errs);
231 vstream_fflush(VSTREAM_OUT);
232
233 vstring_free(state.temp1);
234 vstring_free(state.temp2);
235 vstring_free(addr);
236 argv_free(masq_domains);
237
238 return (0);
239 }
240
241 #endif
242