113 lines
2.3 KiB
C
113 lines
2.3 KiB
C
/*
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* detect.c - Detect content
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* The author licenses this file
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* to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing,
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* software distributed under the License is distributed on an
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* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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* KIND, either express or implied. See the License for the
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* specific language governing permissions and limitations
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* under the License.
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*/
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#include <stddef.h>
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#define _GNU_SOURCE
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#include <string.h>
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#include "detect.h"
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char* pgp_signatures[] =
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{
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"application/pgp-encrypted",
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"application/pgp-signature",
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"-----BEGIN PGP SIGNATURE-----",
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"-----BEGIN PGP MESSAGE-----"
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};
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char* dkim_signatures[] =
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{
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"DKIM-Signature:"
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};
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bool detect_pgp(struct email_t* mail){
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size_t points = 0;
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for(size_t i = 0; i < (sizeof(pgp_signatures)/sizeof(char*));i++){
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if(strcasestr(mail->message,
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pgp_signatures[i]) != NULL){
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points++;
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}
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}
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return points >= 2;
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}
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bool detect_dkim(struct email_t* mail){
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size_t points = 0;
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for(size_t i = 0; i < (sizeof(dkim_signatures)/sizeof(char*));i++){
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if(strcasestr(mail->message, dkim_signatures[i]) != NULL
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&& strcasestr(mail->message, dkim_signatures[i])
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<= (mail->message+mail->header_len)){
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points++;
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}
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}
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return points >= 1;
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}
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/* If body hasn't started yet, it returns NULL, if it has started, it returns
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* the pointer to the beginning of the newline.
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*/
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char* detect_start_of_body(char* message){
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const char* data = "DATA";
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char* data_cmd = strcasestr(message, data);
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for(;data_cmd != NULL; data_cmd = strcasestr(data_cmd+1, data)){
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if(data_cmd == NULL){
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return NULL;
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}
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if(data_cmd == message){
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/* You don't start an smtp conversation with data eh? */
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return NULL;
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}
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char before = data_cmd[-1];
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char after = data_cmd[strlen(data)+1];
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if(before == '\n' || after == '\r'){
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/* Find the end of that line, otherwise fail... */
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for(size_t i = 0; data_cmd[i] != '\0'; i++){
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if(data_cmd[i] == '\n'){
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return data_cmd+i+1;
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}
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}
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}
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}
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return NULL;
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}
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char* detect_end_of_body(char* message){
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const char* data = "\r\n.\r\n";
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return strstr(message, data);
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}
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