1 /* $NetBSD: cleanup_masquerade.c,v 1.1.1.3 2014/07/06 19:27:49 tron 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 #ifdef STRCASECMP_IN_STRINGS_H 57 #include <strings.h> 58 #endif 59 60 /* Utility library. */ 61 62 #include <msg.h> 63 #include <vstring.h> 64 #include <argv.h> 65 #include <htable.h> 66 #include <mymalloc.h> 67 #include <stringops.h> 68 69 /* Global library. */ 70 71 #include <mail_params.h> 72 #include <tok822.h> 73 #include <quote_822_local.h> 74 75 /* Application-specific. */ 76 77 #include "cleanup.h" 78 79 #define STR vstring_str 80 81 /* cleanup_masquerade_external - masquerade address external form */ 82 83 int cleanup_masquerade_external(CLEANUP_STATE *state, VSTRING *addr, 84 ARGV *masq_domains) 85 { 86 char *domain; 87 ssize_t domain_len; 88 char **masqp; 89 char *masq; 90 ssize_t masq_len; 91 char *parent; 92 int truncate; 93 int did_rewrite = 0; 94 95 /* Stuff for excluded names. */ 96 char *name; 97 int excluded; 98 99 /* 100 * Find the domain part. 101 */ 102 if ((domain = strrchr(STR(addr), '@')) == 0) 103 return (0); 104 domain += 1; 105 domain_len = strlen(domain); 106 107 /* 108 * Don't masquerade excluded names (regardless of domain). 109 */ 110 if (*var_masq_exceptions) { 111 name = mystrndup(STR(addr), domain - 1 - STR(addr)); 112 excluded = (string_list_match(cleanup_masq_exceptions, lowercase(name)) != 0); 113 myfree(name); 114 if (cleanup_masq_exceptions->error) { 115 msg_info("%s: %s map lookup problem -- " 116 "message not accepted, try again later", 117 state->queue_id, VAR_MASQ_EXCEPTIONS); 118 state->errs |= CLEANUP_STAT_WRITE; 119 } 120 if (excluded) 121 return (0); 122 } 123 124 /* 125 * If any parent domain matches the list of masquerade domains, replace 126 * the domain in the address and terminate. If the domain matches a 127 * masquerade domain, leave it alone. Order of specification matters. 128 */ 129 for (masqp = masq_domains->argv; (masq = *masqp) != 0; masqp++) { 130 for (truncate = 1; *masq == '!'; masq++) 131 truncate = !truncate; 132 masq_len = strlen(masq); 133 if (masq_len == 0) 134 continue; 135 if (masq_len == domain_len) { 136 if (strcasecmp(masq, domain) == 0) 137 break; 138 } else if (masq_len < domain_len) { 139 parent = domain + domain_len - masq_len; 140 if (parent[-1] == '.' && strcasecmp(masq, parent) == 0) { 141 if (truncate) { 142 if (msg_verbose) 143 msg_info("masquerade: %s -> %s", domain, masq); 144 vstring_truncate(addr, domain - STR(addr)); 145 vstring_strcat(addr, masq); 146 did_rewrite = 1; 147 } 148 break; 149 } 150 } 151 } 152 return (did_rewrite); 153 } 154 155 /* cleanup_masquerade_tree - masquerade address node */ 156 157 int cleanup_masquerade_tree(CLEANUP_STATE *state, TOK822 *tree, 158 ARGV *masq_domains) 159 { 160 VSTRING *temp = vstring_alloc(100); 161 int did_rewrite; 162 163 tok822_externalize(temp, tree->head, TOK822_STR_DEFL); 164 did_rewrite = cleanup_masquerade_external(state, temp, masq_domains); 165 tok822_free_tree(tree->head); 166 tree->head = tok822_scan(STR(temp), &tree->tail); 167 168 vstring_free(temp); 169 return (did_rewrite); 170 } 171 172 /* cleanup_masquerade_internal - masquerade address internal form */ 173 174 int cleanup_masquerade_internal(CLEANUP_STATE *state, VSTRING *addr, 175 ARGV *masq_domains) 176 { 177 VSTRING *temp = vstring_alloc(100); 178 int did_rewrite; 179 180 quote_822_local(temp, STR(addr)); 181 did_rewrite = cleanup_masquerade_external(state, temp, masq_domains); 182 unquote_822_local(addr, STR(temp)); 183 184 vstring_free(temp); 185 return (did_rewrite); 186 } 187 188 /* 189 * Code for stand-alone testing. Instead of using main.cf, specify the strip 190 * list and the candidate domain on the command line. Specify null arguments 191 * for data that should be empty. 192 */ 193 #ifdef TEST 194 195 #include <vstream.h> 196 197 char *var_masq_exceptions; 198 STRING_LIST *cleanup_masq_exceptions; 199 200 int main(int argc, char **argv) 201 { 202 VSTRING *addr; 203 ARGV *masq_domains; 204 CLEANUP_STATE state; 205 206 if (argc != 4) 207 msg_fatal("usage: %s exceptions masquerade_list address", argv[0]); 208 209 var_masq_exceptions = argv[1]; 210 cleanup_masq_exceptions = 211 string_list_init(MATCH_FLAG_RETURN, var_masq_exceptions); 212 masq_domains = argv_split(argv[2], " ,\t\r\n"); 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 cleanup_masquerade_external(&state, addr, masq_domains); 225 226 vstream_printf("result: %s\n", STR(addr)); 227 vstream_printf("errs: %d\n", state.errs); 228 vstream_fflush(VSTREAM_OUT); 229 230 vstring_free(addr); 231 argv_free(masq_domains); 232 233 return (0); 234 } 235 236 #endif 237