Commit | Line | Data |
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420a0d19 CE |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
5 | /* SRS - Sender rewriting scheme support | |
6 | (C)2004 Miles Wilton <miles@mirtol.com> | |
7 | ||
8 | SRS Support Version: 1.0a | |
9 | ||
10 | License: GPL */ | |
11 | ||
12 | #include "exim.h" | |
13 | #ifdef EXPERIMENTAL_SRS | |
14 | ||
15 | #include <srs_alt.h> | |
16 | #include "srs.h" | |
17 | ||
18 | srs_t *srs = NULL; | |
19 | uschar *srs_db_forward = NULL; | |
20 | uschar *srs_db_reverse = NULL; | |
21 | ||
22 | ||
23 | /* srs_init just initialises libsrs and creates (if necessary) | |
24 | an srs object to use for all srs calls in this instance */ | |
25 | ||
26 | int eximsrs_init() | |
27 | { | |
28 | uschar *list = srs_config; | |
29 | uschar secret_buf[SRS_MAX_SECRET_LENGTH]; | |
30 | uschar *secret = NULL; | |
31 | uschar sbuf[4]; | |
32 | uschar *sbufp; | |
33 | ||
34 | /* Check if this instance of Exim has not initialized SRS */ | |
35 | if(srs == NULL) | |
36 | { | |
37 | int co = 0; | |
38 | int hashlen, maxage; | |
39 | BOOL usetimestamp, usehash; | |
40 | ||
41 | /* Copy config vars */ | |
42 | hashlen = srs_hashlength; | |
43 | maxage = srs_maxage; | |
44 | usetimestamp = srs_usetimestamp; | |
45 | usehash = srs_usehash; | |
46 | ||
47 | /* Pass srs_config var (overrides new config vars) */ | |
48 | co = 0; | |
49 | if(srs_config != NULL) | |
50 | { | |
51 | secret = string_nextinlist(&list, &co, secret_buf, SRS_MAX_SECRET_LENGTH); | |
52 | ||
53 | if((sbufp = string_nextinlist(&list, &co, sbuf, sizeof(sbuf))) != NULL) | |
54 | maxage = atoi(sbuf); | |
55 | ||
56 | if((sbufp = string_nextinlist(&list, &co, sbuf, sizeof(sbuf))) != NULL) | |
57 | hashlen = atoi(sbuf); | |
58 | ||
59 | if((sbufp = string_nextinlist(&list, &co, sbuf, sizeof(sbuf))) != NULL) | |
60 | usetimestamp = atoi(sbuf); | |
61 | ||
62 | if((sbufp = string_nextinlist(&list, &co, sbuf, sizeof(sbuf))) != NULL) | |
63 | usehash = atoi(sbuf); | |
64 | } | |
65 | ||
66 | if(srs_hashmin == -1) | |
67 | srs_hashmin = hashlen; | |
68 | ||
69 | /* First secret specified in secrets? */ | |
70 | co = 0; | |
71 | list = srs_secrets; | |
72 | if(secret == NULL || *secret == '\0') | |
73 | { | |
74 | if((secret = string_nextinlist(&list, &co, secret_buf, SRS_MAX_SECRET_LENGTH)) == NULL) | |
75 | { | |
76 | log_write(0, LOG_MAIN | LOG_PANIC, | |
77 | "SRS Configuration Error: No secret specified"); | |
78 | return DEFER; | |
79 | } | |
80 | } | |
81 | ||
82 | /* Check config */ | |
83 | if(maxage < 0 || maxage > 365) | |
84 | { | |
85 | log_write(0, LOG_MAIN | LOG_PANIC, | |
86 | "SRS Configuration Error: Invalid maximum timestamp age"); | |
87 | return DEFER; | |
88 | } | |
89 | if(hashlen < 1 || hashlen > 20 || srs_hashmin < 1 || srs_hashmin > 20) | |
90 | { | |
91 | log_write(0, LOG_MAIN | LOG_PANIC, | |
92 | "SRS Configuration Error: Invalid hash length"); | |
93 | return DEFER; | |
94 | } | |
95 | ||
96 | if((srs = srs_open(secret, Ustrlen(secret), maxage, hashlen, srs_hashmin)) == NULL) | |
97 | { | |
98 | log_write(0, LOG_MAIN | LOG_PANIC, | |
99 | "Failed to allocate SRS memory"); | |
100 | return DEFER; | |
101 | } | |
102 | ||
103 | srs_set_option(srs, SRS_OPTION_USETIMESTAMP, usetimestamp); | |
104 | srs_set_option(srs, SRS_OPTION_USEHASH, usehash); | |
105 | ||
106 | /* Extra secrets? */ | |
107 | while((secret = string_nextinlist(&list, &co, secret_buf, SRS_MAX_SECRET_LENGTH)) != NULL) | |
108 | srs_add_secret(srs, secret, (Ustrlen(secret) > SRS_MAX_SECRET_LENGTH) ? SRS_MAX_SECRET_LENGTH : Ustrlen(secret)); | |
109 | ||
110 | DEBUG(D_any) | |
111 | debug_printf("SRS initialized\n"); | |
112 | } | |
113 | ||
114 | return OK; | |
115 | } | |
116 | ||
117 | ||
118 | int eximsrs_done() | |
119 | { | |
120 | if(srs != NULL) | |
121 | srs_close(srs); | |
122 | ||
123 | srs = NULL; | |
124 | ||
125 | return OK; | |
126 | } | |
127 | ||
128 | ||
129 | int eximsrs_forward(uschar **result, uschar *orig_sender, uschar *domain) | |
130 | { | |
131 | char res[512]; | |
132 | int n; | |
133 | ||
134 | if((n = srs_forward(srs, orig_sender, domain, res, sizeof(res))) & SRS_RESULT_FAIL) | |
135 | { | |
136 | DEBUG(D_any) | |
137 | debug_printf("srs_forward failed (%s, %s): %s\n", orig_sender, domain, srs_geterrormsg(n)); | |
138 | return DEFER; | |
139 | } | |
140 | ||
141 | *result = string_copy(res); | |
142 | return OK; | |
143 | } | |
144 | ||
145 | ||
146 | int eximsrs_reverse(uschar **result, uschar *address) | |
147 | { | |
148 | char res[512]; | |
149 | int n; | |
150 | ||
151 | if((n = srs_reverse(srs, address, res, sizeof(res))) & SRS_RESULT_FAIL) | |
152 | { | |
153 | DEBUG(D_any) | |
154 | debug_printf("srs_reverse failed (%s): %s\n", address, srs_geterrormsg(n)); | |
155 | if(n == SRS_RESULT_NOTSRS || n == SRS_RESULT_BADSRS) | |
156 | return DECLINE; | |
157 | if(n == SRS_RESULT_BADHASH || n == SRS_RESULT_BADTIMESTAMP || n == SRS_RESULT_TIMESTAMPEXPIRED) | |
158 | return FAIL; | |
159 | return DEFER; | |
160 | } | |
161 | ||
162 | *result = string_copy(res); | |
163 | return OK; | |
164 | } | |
165 | ||
166 | ||
167 | int eximsrs_db_set(BOOL reverse, uschar *srs_db) | |
168 | { | |
169 | if(reverse) | |
170 | srs_db_reverse = (srs_db == NULL ? NULL : string_copy(srs_db)); | |
171 | else | |
172 | srs_db_forward = (srs_db == NULL ? NULL : string_copy(srs_db)); | |
173 | ||
174 | if(srs_set_db_functions(srs, (srs_db_forward ? eximsrs_db_insert : NULL), | |
175 | (srs_db_reverse ? eximsrs_db_lookup : NULL)) & SRS_RESULT_FAIL) | |
176 | return DEFER; | |
177 | ||
178 | return OK; | |
179 | } | |
180 | ||
181 | ||
182 | srs_result eximsrs_db_insert(srs_t *srs, char *data, uint data_len, char *result, uint result_len) | |
183 | { | |
184 | uschar *res; | |
185 | uschar buf[64]; | |
186 | ||
187 | if(srs_db_forward == NULL) | |
188 | return SRS_RESULT_DBERROR; | |
189 | ||
190 | srs_db_address = string_copyn(data, data_len); | |
191 | if(srs_generate_unique_id(srs, srs_db_address, buf, 64) & SRS_RESULT_FAIL) | |
192 | return SRS_RESULT_DBERROR; | |
193 | ||
194 | srs_db_key = string_copyn(buf, 16); | |
195 | ||
196 | if((res = expand_string(srs_db_forward)) == NULL) | |
197 | return SRS_RESULT_DBERROR; | |
198 | ||
199 | if(result_len < 17) | |
200 | return SRS_RESULT_DBERROR; | |
201 | ||
202 | Ustrncpy(result, srs_db_key, result_len); | |
203 | ||
204 | return SRS_RESULT_OK; | |
205 | } | |
206 | ||
207 | ||
208 | srs_result eximsrs_db_lookup(srs_t *srs, char *data, uint data_len, char *result, uint result_len) | |
209 | { | |
210 | uschar *res; | |
211 | ||
212 | if(srs_db_reverse == NULL) | |
213 | return SRS_RESULT_DBERROR; | |
214 | ||
215 | srs_db_key = string_copyn(data, data_len); | |
216 | if((res = expand_string(srs_db_reverse)) == NULL) | |
217 | return SRS_RESULT_DBERROR; | |
218 | ||
219 | if(Ustrlen(res) >= result_len) | |
220 | return SRS_RESULT_ADDRESSTOOLONG; | |
221 | ||
222 | strncpy(result, res, result_len); | |
223 | ||
224 | return SRS_RESULT_OK; | |
225 | } | |
226 | ||
227 | ||
228 | #endif | |
229 |