| 1 |
/* Mixmaster version 3.0 -- (C) 1999 - 2004 Anonymizer Inc. and others.
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| 2 |
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| 3 |
Mixmaster may be redistributed and modified under certain conditions.
|
| 4 |
This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF
|
| 5 |
ANY KIND, either express or implied. See the file COPYRIGHT for
|
| 6 |
details.
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| 7 |
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| 8 |
Encrypt message for Mixmaster chain
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| 9 |
$Id$ */
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| 10 |
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| 11 |
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| 12 |
#include "mix3.h"
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| 13 |
#include <string.h>
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| 14 |
#include <stdlib.h>
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| 15 |
#include <time.h>
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| 16 |
#include <ctype.h>
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| 17 |
#include <assert.h>
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| 18 |
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| 19 |
#define N(X) (isdigit(X) ? (X)-'0' : 0)
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| 20 |
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| 21 |
int prepare_type2list(BUFFER *out)
|
| 22 |
{
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| 23 |
FILE *list;
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| 24 |
char line[LINELEN], name[LINELEN], addr[LINELEN], keyid[LINELEN],
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| 25 |
version[LINELEN], flags[LINELEN], createdstr[LINELEN], expiresstr[LINELEN];
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| 26 |
int assigned;
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| 27 |
time_t created, expires;
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| 28 |
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| 29 |
list = mix_openfile(TYPE2LIST, "r");
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| 30 |
if (list == NULL) {
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| 31 |
list = mix_openfile(PUBRING, "r");
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| 32 |
if (list == NULL)
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| 33 |
return (-1);
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| 34 |
}
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| 35 |
while (fgets(line, sizeof(line), list) != NULL) {
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| 36 |
if (strleft(line, begin_key)) {
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| 37 |
while (fgets(line, sizeof(line), list) != NULL &&
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| 38 |
!strleft(line, end_key)) ;
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| 39 |
} else if (strlen(line) > 36 && line[0] != '#') {
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| 40 |
assigned = sscanf(line, "%127s %127s %127s %127s %127s %127s %127s",
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| 41 |
name, addr, keyid, version, flags, createdstr, expiresstr);
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| 42 |
if (assigned < 4)
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| 43 |
continue;
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| 44 |
if (assigned >= 6) {
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| 45 |
created = parse_yearmonthday(createdstr);
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| 46 |
if (created == 0 || created == -1) {
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| 47 |
errlog(WARNING, "Cannot parse creation date of key %s.\n", keyid);
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| 48 |
continue;
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| 49 |
};
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| 50 |
if (created > time(NULL)) {
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| 51 |
errlog(WARNING, "Key %s created in the future.\n", keyid);
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| 52 |
continue;
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| 53 |
};
|
| 54 |
}
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| 55 |
if (assigned >= 7) {
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| 56 |
expires = parse_yearmonthday(expiresstr);
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| 57 |
if (expires == 0 || expires == -1) {
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| 58 |
errlog(WARNING, "Cannot parse expiration date of key %s.\n", keyid);
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| 59 |
continue;
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| 60 |
};
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| 61 |
if (expires < time(NULL)) {
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| 62 |
errlog(WARNING, "Key %s has expired.\n", keyid);
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| 63 |
continue;
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| 64 |
};
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| 65 |
}
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| 66 |
buf_appends(out, line);
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| 67 |
}
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| 68 |
}
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| 69 |
fclose(list);
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| 70 |
return (0);
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| 71 |
}
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| 72 |
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| 73 |
int mix2_rlist(REMAILER remailer[], int badchains[MAXREM][MAXREM])
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| 74 |
{
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| 75 |
FILE *list, *excl;
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| 76 |
int n, i, listed = 0;
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| 77 |
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| 78 |
char line[LINELEN], name[LINELEN], addr[LINELEN], keyid[LINELEN],
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| 79 |
version[LINELEN], flags[LINELEN], createdstr[LINELEN], expiresstr[LINELEN];
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| 80 |
int assigned;
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| 81 |
time_t created, expires;
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| 82 |
BUFFER *starex;
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| 83 |
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| 84 |
starex = buf_new();
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| 85 |
excl = mix_openfile(STAREX, "r");
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| 86 |
if (excl != NULL) {
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| 87 |
buf_read(starex, excl);
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| 88 |
fclose(excl);
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| 89 |
}
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| 90 |
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| 91 |
list = mix_openfile(TYPE2LIST, "r");
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| 92 |
if (list == NULL) {
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| 93 |
list = mix_openfile(PUBRING, "r");
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| 94 |
if (list == NULL) {
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| 95 |
buf_free(starex);
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| 96 |
return (-1);
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}
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}
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for (n = 1; fgets(line, sizeof(line), list) != NULL && n < MAXREM;)
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| 100 |
if (strleft(line, begin_key)) {
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| 101 |
while (fgets(line, sizeof(line), list) != NULL &&
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| 102 |
!strleft(line, end_key)) ;
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| 103 |
} else if (strlen(line) > 36 && line[0] != '#') {
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| 104 |
flags[0] = '\0';
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| 105 |
assigned = sscanf(line, "%127s %127s %127s %127s %127s %127s %127s",
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name, addr, keyid, version, flags, createdstr, expiresstr);
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if (assigned < 4)
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continue;
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| 109 |
if (assigned >= 6) {
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| 110 |
created = parse_yearmonthday(createdstr);
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| 111 |
if (created == 0 || created == -1) {
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| 112 |
errlog(WARNING, "Cannot parse creation date of key %s.\n", keyid);
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continue;
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};
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| 115 |
if (created > time(NULL)) {
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| 116 |
errlog(WARNING, "Key %s created in the future.\n", keyid);
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| 117 |
continue;
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| 118 |
};
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}
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| 120 |
if (assigned >= 7) {
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| 121 |
expires = parse_yearmonthday(expiresstr);
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| 122 |
if (expires == 0 || expires == -1) {
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| 123 |
errlog(WARNING, "Cannot parse expiration date of key %s.\n", keyid);
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| 124 |
continue;
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};
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| 126 |
if (expires < time(NULL)) {
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| 127 |
errlog(WARNING, "Key %s has expired.\n", keyid);
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| 128 |
continue;
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| 129 |
};
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| 130 |
}
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| 131 |
strncpy(remailer[n].name, name, sizeof(remailer[n].name));
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| 132 |
remailer[n].name[sizeof(remailer[n].name) - 1] = '\0';
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| 133 |
strncpy(remailer[n].addr, addr, sizeof(remailer[n].addr));
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remailer[n].addr[sizeof(remailer[n].addr) - 1] = '\0';
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| 135 |
remailer[n].flags.mix = 1;
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| 136 |
remailer[n].flags.cpunk = 0;
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| 137 |
remailer[n].flags.nym = 0;
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| 138 |
remailer[n].flags.newnym = 0;
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| 139 |
id_decode(keyid, remailer[n].keyid);
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| 140 |
remailer[n].version = N(version[0]);
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| 141 |
remailer[n].flags.compress = strfind(flags, "C");
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| 142 |
remailer[n].flags.post = strfind(flags, "N");
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| 143 |
remailer[n].flags.middle = strfind(flags, "M");
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| 144 |
remailer[n].info[0].reliability = 0;
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| 145 |
remailer[n].info[0].latency = 0;
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| 146 |
remailer[n].info[0].history[0] = '\0';
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| 147 |
remailer[n].flags.star_ex = bufifind(starex, name);
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| 148 |
n++;
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| 149 |
}
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| 150 |
fclose(list);
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| 151 |
list = mix_openfile(TYPE2REL, "r");
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| 152 |
if (list != NULL) {
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| 153 |
while (fgets(line, sizeof(line), list) != NULL &&
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| 154 |
!strleft(line, "--------------------------------------------")) {
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| 155 |
if (strleft(line, "Last update:")) {
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| 156 |
int generated;
|
| 157 |
int now = time(NULL);
|
| 158 |
char *tmp = line + strlen("Last update:") + 1;
|
| 159 |
generated = parsedate(tmp);
|
| 160 |
if (generated == -1) {
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| 161 |
/* For some weird reason, this isn't rfc822 */
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| 162 |
if (strleft(tmp, "Mon") ||
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| 163 |
strleft(tmp, "Tue") ||
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| 164 |
strleft(tmp, "Wed") ||
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| 165 |
strleft(tmp, "Thu") ||
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| 166 |
strleft(tmp, "Fri") ||
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| 167 |
strleft(tmp, "Sat") ||
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| 168 |
strleft(tmp, "Sun"))
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| 169 |
tmp += 3;
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| 170 |
generated = parsedate(tmp);
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| 171 |
}
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| 172 |
now = time(NULL);
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| 173 |
if (generated != -1 && generated < now - SECONDSPERDAY)
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| 174 |
errlog(WARNING, "Remailer Reliability Statistics are older than one day (check your clock?).\n");
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| 175 |
if (generated != -1 && generated > now)
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| 176 |
errlog(WARNING, "Remailer Reliability Statistics are from the future (check your clock?).\n");
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| 177 |
}
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| 178 |
};
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| 179 |
while (fgets(line, sizeof(line), list) != NULL &&
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| 180 |
!strleft(line, "</PRE>"))
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| 181 |
if (strlen(line) >= 44 && strlen(line) <= 46)
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| 182 |
for (i = 1; i < n; i++)
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| 183 |
if (strleft(line, remailer[i].name) &&
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| 184 |
line[strlen(remailer[i].name)] == ' ') {
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| 185 |
strncpy(remailer[i].info[0].history, line + 15, 12);
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| 186 |
remailer[i].info[0].history[12] = '\0';
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| 187 |
remailer[i].info[0].reliability = 10000 * N(line[37])
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+ 1000 * N(line[38]) + 100 * N(line[39])
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+ 10 * N(line[41]) + N(line[42]);
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| 190 |
remailer[i].info[0].latency = 36000 * N(line[28])
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| 191 |
+ 3600 * N(line[29]) + 600 * N(line[31])
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| 192 |
+ 60 * N(line[32]) + 10 * N(line[34])
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| 193 |
+ N(line[35]);
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| 194 |
listed++;
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| 195 |
}
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| 196 |
fclose(list);
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}
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| 198 |
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| 199 |
parse_badchains(badchains, TYPE2REL, "Broken type-II remailer chains", remailer, n);
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| 200 |
if (listed < 4) /* we have no valid reliability info */
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for (i = 1; i < n; i++)
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| 202 |
remailer[i].info[0].reliability = 10000;
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| 203 |
buf_free(starex);
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return (n);
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}
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| 207 |
static int send_packet(int numcopies, BUFFER *packet, int chain[],
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| 208 |
int chainlen, int packetnum, int numpackets,
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| 209 |
BUFFER *mid, REMAILER remailer[], int badchains[MAXREM][MAXREM],
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| 210 |
int maxrem, char *redirect_to, int ignore_constraints_if_necessary,
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| 211 |
BUFFER *feedback)
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| 212 |
/*
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| 213 |
* Puts a mix packet in the pool.
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| 214 |
*
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| 215 |
* numcopies ... how often to put this packet into the pool
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| 216 |
* i.e. send it. required that random remailers are in the chain.
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* packet ... the payload, 10240 bytes in size.
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| 218 |
* chain ... the chain to send this message along
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| 219 |
* chainlen ... length of the chain
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| 220 |
* packetnum ... in multi-packet messages (fragmented) the serial of this packet
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| 221 |
* numpackets ... the total number of packets
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| 222 |
* mid ... the message ID (required for fragmented packets
|
| 223 |
* remailer ... information about remailers, their reliabilities, capabilities, etc.
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| 224 |
* badchains ... broken chain information
|
| 225 |
* maxrem ... the number of remailers in remailer[] and badchains[]
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| 226 |
* redirect_to ... if this is not-null it needs to be an email address.
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| 227 |
* in this case packet needs to be not only the body, but a
|
| 228 |
* complete mixmaster packet of 20480 bytes in size (20 headers + body).
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| 229 |
* the chain given is prepended to the one already encrypted in
|
| 230 |
* the existing message. If this exceeds the allowed 20 hops in total
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| 231 |
* the message is corrupted, the last node will realize this.
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| 232 |
* This is useful if you want to reroute an existing mixmaster message
|
| 233 |
* that has foo as the next hop via a chain so that the packet will
|
| 234 |
* actually flow hop1,hop2,hop3,foo,....
|
| 235 |
* ignore_constraints_if_necessary .. to be used when randhopping messages.
|
| 236 |
* if a chain can not be constructed otherwhise, maxlat and
|
| 237 |
* minrel are ignored.
|
| 238 |
* feedback ... a buffer to write feedback to
|
| 239 |
*/
|
| 240 |
{
|
| 241 |
BUFFER *pid, *out, *header, *other, *encrypted, *key, *body;
|
| 242 |
BUFFER *iv, *ivarray, *temp;
|
| 243 |
BUFFER *pubkey;
|
| 244 |
char addr[LINELEN];
|
| 245 |
int thischain[20];
|
| 246 |
int hop;
|
| 247 |
int c, i;
|
| 248 |
int timestamp = 0;
|
| 249 |
int israndom = 0;
|
| 250 |
int err = 1;
|
| 251 |
|
| 252 |
body = buf_new();
|
| 253 |
pid = buf_new();
|
| 254 |
out = buf_new();
|
| 255 |
header = buf_new();
|
| 256 |
other = buf_new();
|
| 257 |
key = buf_new();
|
| 258 |
encrypted = buf_new();
|
| 259 |
iv = buf_new();
|
| 260 |
ivarray = buf_new();
|
| 261 |
temp = buf_new();
|
| 262 |
|
| 263 |
if (redirect_to != NULL) {
|
| 264 |
assert(packet->length == 20480);
|
| 265 |
buf_append(header, packet->data, 10240);
|
| 266 |
buf_append(temp, packet->data + 10240, 10240);
|
| 267 |
buf_clear(packet);
|
| 268 |
buf_cat(packet, temp);
|
| 269 |
} else
|
| 270 |
assert(packet->length == 10240);
|
| 271 |
|
| 272 |
buf_setrnd(pid, 16);
|
| 273 |
|
| 274 |
for (c = 0; c < numcopies; c++) {
|
| 275 |
buf_set(body, packet);
|
| 276 |
|
| 277 |
for (hop = 0; hop < chainlen; hop++)
|
| 278 |
thischain[hop] = chain[hop];
|
| 279 |
|
| 280 |
israndom = chain_rand(remailer, badchains, maxrem, thischain, chainlen, 0, ignore_constraints_if_necessary);
|
| 281 |
if (israndom == -1) {
|
| 282 |
err = -1;
|
| 283 |
clienterr(feedback, "No reliable remailers!");
|
| 284 |
}
|
| 285 |
if ((numcopies > 1 || numpackets > 1) && !israndom && (chainlen != 1)) {
|
| 286 |
clienterr(feedback,
|
| 287 |
"Multi-packet message without random remailers!");
|
| 288 |
err = -1;
|
| 289 |
goto end;
|
| 290 |
}
|
| 291 |
for (hop = 0; hop < chainlen; hop++) {
|
| 292 |
switch (remailer[thischain[hop]].version) {
|
| 293 |
case 2:
|
| 294 |
case 3: /* not implemented yet; fall back to version 2 */
|
| 295 |
/* create header chart to be encrypted with the session key */
|
| 296 |
if (numcopies > 1 && hop == 0 && redirect_to == NULL)
|
| 297 |
buf_set(encrypted, pid); /* same ID only at final hop */
|
| 298 |
else
|
| 299 |
buf_setrnd(encrypted, 16);
|
| 300 |
buf_setrnd(key, 24); /* key for encrypting the body */
|
| 301 |
buf_cat(encrypted, key);
|
| 302 |
buf_setrnd(iv, 8); /* IV for encrypting the body */
|
| 303 |
|
| 304 |
if (hop > 0 || redirect_to != NULL) {
|
| 305 |
/* IVs for header chart encryption */
|
| 306 |
buf_setrnd(ivarray, 18 * 8);
|
| 307 |
buf_cat(ivarray, iv); /* 19th IV equals the body IV */
|
| 308 |
|
| 309 |
buf_appendc(encrypted, 0);
|
| 310 |
buf_cat(encrypted, ivarray);
|
| 311 |
memset(addr, 0, 80);
|
| 312 |
if (hop == 0) {
|
| 313 |
assert(redirect_to != NULL);
|
| 314 |
strncpy(addr, redirect_to, 80);
|
| 315 |
} else {
|
| 316 |
assert(hop > 0);
|
| 317 |
strcpy(addr, remailer[thischain[hop - 1]].addr);
|
| 318 |
};
|
| 319 |
buf_append(encrypted, addr, 80);
|
| 320 |
} else {
|
| 321 |
if (numpackets == 1)
|
| 322 |
buf_appendc(encrypted, 1);
|
| 323 |
else {
|
| 324 |
buf_appendc(encrypted, 2);
|
| 325 |
buf_appendc(encrypted, (byte) packetnum);
|
| 326 |
buf_appendc(encrypted, (byte) numpackets);
|
| 327 |
}
|
| 328 |
buf_cat(encrypted, mid);
|
| 329 |
buf_cat(encrypted, iv); /* body encryption IV */
|
| 330 |
}
|
| 331 |
|
| 332 |
/* timestamp */
|
| 333 |
buf_appends(encrypted, "0000");
|
| 334 |
buf_appendc(encrypted, '\0'); /* timestamp magic */
|
| 335 |
timestamp = time(NULL) / SECONDSPERDAY - rnd_number(4);
|
| 336 |
buf_appendi_lo(encrypted, timestamp);
|
| 337 |
|
| 338 |
/* message digest for this header */
|
| 339 |
digest_md5(encrypted, temp);
|
| 340 |
buf_cat(encrypted, temp);
|
| 341 |
buf_pad(encrypted, 328);
|
| 342 |
|
| 343 |
/* encrypt message body */
|
| 344 |
buf_crypt(body, key, iv, ENCRYPT);
|
| 345 |
|
| 346 |
if (hop > 0 || redirect_to != NULL) {
|
| 347 |
/* encrypt the other header charts */
|
| 348 |
buf_clear(other);
|
| 349 |
for (i = 0; i < 19; i++) {
|
| 350 |
buf_clear(iv);
|
| 351 |
buf_clear(temp);
|
| 352 |
buf_append(iv, ivarray->data + 8 * i, 8);
|
| 353 |
buf_append(temp, header->data + 512 * i, 512);
|
| 354 |
buf_crypt(temp, key, iv, ENCRYPT);
|
| 355 |
buf_cat(other, temp);
|
| 356 |
}
|
| 357 |
} else
|
| 358 |
buf_setrnd(other, 19 * 512); /* fill with random data */
|
| 359 |
|
| 360 |
/* create session key and IV to encrypt the header ... */
|
| 361 |
buf_setrnd(key, 24);
|
| 362 |
buf_setrnd(iv, 8);
|
| 363 |
buf_crypt(encrypted, key, iv, ENCRYPT);
|
| 364 |
pubkey = buf_new();
|
| 365 |
err = db_getpubkey(remailer[thischain[hop]].keyid, pubkey);
|
| 366 |
if (err == -1)
|
| 367 |
goto end;
|
| 368 |
err = pk_encrypt(key, pubkey); /* ... and encrypt the
|
| 369 |
session key */
|
| 370 |
buf_free(pubkey);
|
| 371 |
if (err == -1 || key->length != 128) {
|
| 372 |
clienterr(feedback, "Encryption failed!");
|
| 373 |
err = -1;
|
| 374 |
goto end;
|
| 375 |
}
|
| 376 |
/* now build the new header */
|
| 377 |
buf_clear(header);
|
| 378 |
buf_append(header, remailer[thischain[hop]].keyid, 16);
|
| 379 |
buf_appendc(header, 128);
|
| 380 |
buf_cat(header, key);
|
| 381 |
buf_cat(header, iv);
|
| 382 |
buf_cat(header, encrypted);
|
| 383 |
buf_pad(header, 512);
|
| 384 |
buf_cat(header, other);
|
| 385 |
break;
|
| 386 |
default:
|
| 387 |
err = -1;
|
| 388 |
goto end;
|
| 389 |
}
|
| 390 |
}
|
| 391 |
|
| 392 |
/* build the message */
|
| 393 |
buf_sets(out, remailer[thischain[chainlen - 1]].addr);
|
| 394 |
buf_nl(out);
|
| 395 |
buf_cat(out, header);
|
| 396 |
buf_cat(out, body);
|
| 397 |
assert(header->length == 10240 && body->length == 10240);
|
| 398 |
mix_pool(out, INTERMEDIATE, -1);
|
| 399 |
|
| 400 |
if (feedback) {
|
| 401 |
for (hop = chainlen - 1; hop >= 0; hop--) {
|
| 402 |
buf_appends(feedback, remailer[thischain[hop]].name);
|
| 403 |
if (hop > 0)
|
| 404 |
buf_appendc(feedback, ',');
|
| 405 |
}
|
| 406 |
buf_nl(feedback);
|
| 407 |
}
|
| 408 |
}
|
| 409 |
end:
|
| 410 |
buf_free(pid);
|
| 411 |
buf_free(body);
|
| 412 |
buf_free(out);
|
| 413 |
buf_free(header);
|
| 414 |
buf_free(temp);
|
| 415 |
buf_free(other);
|
| 416 |
buf_free(key);
|
| 417 |
buf_free(encrypted);
|
| 418 |
buf_free(iv);
|
| 419 |
buf_free(ivarray);
|
| 420 |
return (err);
|
| 421 |
}
|
| 422 |
|
| 423 |
int redirect_message(BUFFER *sendmsg, char *chainstr, int numcopies, BUFFER *feedback)
|
| 424 |
{
|
| 425 |
BUFFER *field;
|
| 426 |
BUFFER *content;
|
| 427 |
BUFFER *line;
|
| 428 |
char recipient[80] = "";
|
| 429 |
int num = 0;
|
| 430 |
int err = 0;
|
| 431 |
int c;
|
| 432 |
int hop;
|
| 433 |
|
| 434 |
REMAILER remailer[MAXREM];
|
| 435 |
int chain[20];
|
| 436 |
int thischain[20];
|
| 437 |
int chainlen;
|
| 438 |
int badchains[MAXREM][MAXREM];
|
| 439 |
int maxrem;
|
| 440 |
int tempchain[20];
|
| 441 |
int tempchainlen;
|
| 442 |
int israndom;
|
| 443 |
|
| 444 |
field = buf_new();
|
| 445 |
content = buf_new();
|
| 446 |
line = buf_new();
|
| 447 |
|
| 448 |
if (numcopies == 0)
|
| 449 |
numcopies = NUMCOPIES;
|
| 450 |
if (numcopies > 10)
|
| 451 |
numcopies = 10;
|
| 452 |
|
| 453 |
/* Find the recipient */
|
| 454 |
while (buf_getheader(sendmsg, field, content) == 0)
|
| 455 |
if (bufieq(field, "to")) {
|
| 456 |
strncpy(recipient, content->data, sizeof(recipient));
|
| 457 |
num++;
|
| 458 |
};
|
| 459 |
if (num != 1) {
|
| 460 |
clienterr(feedback, "Did not find exactly one To: address!");
|
| 461 |
err = -1;
|
| 462 |
goto end;
|
| 463 |
};
|
| 464 |
|
| 465 |
/* Dearmor the message */
|
| 466 |
err = mix_dearmor(sendmsg, sendmsg);
|
| 467 |
if (err == -1)
|
| 468 |
goto end;
|
| 469 |
assert (sendmsg->length == 20480);
|
| 470 |
|
| 471 |
/* Check the chain */
|
| 472 |
maxrem = mix2_rlist(remailer, badchains);
|
| 473 |
if (maxrem < 1) {
|
| 474 |
clienterr(feedback, "No remailer list!");
|
| 475 |
err = -1;
|
| 476 |
goto end;
|
| 477 |
}
|
| 478 |
chainlen = chain_select(chain, chainstr, maxrem, remailer, 0, line);
|
| 479 |
if (chainlen < 1) {
|
| 480 |
if (line->length)
|
| 481 |
clienterr(feedback, line->data);
|
| 482 |
else
|
| 483 |
clienterr(feedback, "Invalid remailer chain!");
|
| 484 |
err = -1;
|
| 485 |
goto end;
|
| 486 |
} else if (chainlen >= 20) {
|
| 487 |
clienterr(feedback, "A chainlength of 20 will certainly destroy the message!");
|
| 488 |
err = -1;
|
| 489 |
goto end;
|
| 490 |
};
|
| 491 |
|
| 492 |
|
| 493 |
for (c = 0; c < numcopies; c++) {
|
| 494 |
/* if our recipient is a remailer we want to make sure we're not using a known broken chain.
|
| 495 |
* therefore we need to pick the final remailer with care */
|
| 496 |
for (hop = 0; hop < chainlen; hop++)
|
| 497 |
thischain[hop] = chain[hop];
|
| 498 |
if (thischain[0] == 0) {
|
| 499 |
/* Find out, if recipient is a remailer */
|
| 500 |
tempchainlen = chain_select(tempchain, recipient, maxrem, remailer, 0, line);
|
| 501 |
if (tempchainlen < 1 && line->length == 0) {
|
| 502 |
/* recipient is apparently not a remailer we know about */
|
| 503 |
;
|
| 504 |
} else {
|
| 505 |
/* Build a new chain, based on the one we already selected but
|
| 506 |
* with the recipient as the final hop.
|
| 507 |
* This is so that chain_rand properly selects nodes based on
|
| 508 |
* broken chains and DISTANCE */
|
| 509 |
assert(chainlen < 20);
|
| 510 |
for (hop = 0; hop < chainlen; hop++)
|
| 511 |
thischain[hop+1] = thischain[hop];
|
| 512 |
thischain[0] = tempchain[0];
|
| 513 |
|
| 514 |
israndom = chain_rand(remailer, badchains, maxrem, thischain, chainlen + 1, 0, 0);
|
| 515 |
if (israndom == -1) {
|
| 516 |
err = -1;
|
| 517 |
clienterr(feedback, "No reliable remailers!");
|
| 518 |
goto end;
|
| 519 |
}
|
| 520 |
|
| 521 |
/* Remove the added recipient hop */
|
| 522 |
for (hop = 0; hop < chainlen; hop++)
|
| 523 |
thischain[hop] = thischain[hop + 1];
|
| 524 |
};
|
| 525 |
};
|
| 526 |
|
| 527 |
/* queue the packet */
|
| 528 |
if (send_packet(1, sendmsg, thischain, chainlen,
|
| 529 |
-1, -1, NULL,
|
| 530 |
remailer, badchains, maxrem, recipient, 0, feedback) == -1)
|
| 531 |
err = -1;
|
| 532 |
};
|
| 533 |
|
| 534 |
end:
|
| 535 |
buf_free(field);
|
| 536 |
buf_free(content);
|
| 537 |
buf_free(line);
|
| 538 |
return (err);
|
| 539 |
}
|
| 540 |
|
| 541 |
int mix2_encrypt(int type, BUFFER *message, char *chainstr, int numcopies,
|
| 542 |
int ignore_constraints_if_necessary,
|
| 543 |
BUFFER *feedback)
|
| 544 |
{
|
| 545 |
/* returns 0 on success, -1 on error. feedback contains the selected
|
| 546 |
remailer chain or an error message
|
| 547 |
|
| 548 |
ignore_constraints_if_necessary .. to be used when randhopping messages.
|
| 549 |
if a chain can not be constructed otherwhise,
|
| 550 |
maxlat and minrel are ignored.
|
| 551 |
*/
|
| 552 |
|
| 553 |
REMAILER remailer[MAXREM];
|
| 554 |
int badchains[MAXREM][MAXREM];
|
| 555 |
int maxrem;
|
| 556 |
BUFFER *line, *field, *content, *header, *msgdest, *msgheader, *body,
|
| 557 |
*temp, *mid;
|
| 558 |
byte numdest = 0, numhdr = 0;
|
| 559 |
char hdrline[LINELEN];
|
| 560 |
BUFFER *packet;
|
| 561 |
int chain[20];
|
| 562 |
int chainlen;
|
| 563 |
int i;
|
| 564 |
int err = 0;
|
| 565 |
|
| 566 |
mix_init(NULL);
|
| 567 |
packet = buf_new();
|
| 568 |
line = buf_new();
|
| 569 |
field = buf_new();
|
| 570 |
content = buf_new();
|
| 571 |
msgheader = buf_new();
|
| 572 |
msgdest = buf_new();
|
| 573 |
body = buf_new();
|
| 574 |
temp = buf_new();
|
| 575 |
mid = buf_new();
|
| 576 |
header = buf_new();
|
| 577 |
if (feedback)
|
| 578 |
buf_reset(feedback);
|
| 579 |
|
| 580 |
if (numcopies == 0)
|
| 581 |
numcopies = NUMCOPIES;
|
| 582 |
if (numcopies > 10)
|
| 583 |
numcopies = 10;
|
| 584 |
|
| 585 |
maxrem = mix2_rlist(remailer, badchains);
|
| 586 |
if (maxrem < 1) {
|
| 587 |
clienterr(feedback, "No remailer list!");
|
| 588 |
err = -1;
|
| 589 |
goto end;
|
| 590 |
}
|
| 591 |
chainlen = chain_select(chain, chainstr, maxrem, remailer, 0, line);
|
| 592 |
if (chainlen < 1) {
|
| 593 |
if (line->length)
|
| 594 |
clienterr(feedback, line->data);
|
| 595 |
else
|
| 596 |
clienterr(feedback, "Invalid remailer chain!");
|
| 597 |
err = -1;
|
| 598 |
goto end;
|
| 599 |
}
|
| 600 |
if (chain[0] == 0)
|
| 601 |
chain[0] = chain_randfinal(type, remailer, badchains, maxrem, 0, chain, chainlen, ignore_constraints_if_necessary);
|
| 602 |
|
| 603 |
if (chain[0] == -1) {
|
| 604 |
clienterr(feedback, "No reliable remailers!");
|
| 605 |
err = -1;
|
| 606 |
goto end;
|
| 607 |
}
|
| 608 |
switch (remailer[chain[0]].version) {
|
| 609 |
case 2:
|
| 610 |
if (type == MSG_NULL) {
|
| 611 |
memset(hdrline, 0, 80);
|
| 612 |
strcpy(hdrline, "null:");
|
| 613 |
buf_append(msgdest, hdrline, 80);
|
| 614 |
numdest++;
|
| 615 |
} else
|
| 616 |
while (buf_getheader(message, field, content) == 0) {
|
| 617 |
if (bufieq(field, "to")) {
|
| 618 |
memset(hdrline, 0, 80);
|
| 619 |
strncpy(hdrline, content->data, 80);
|
| 620 |
buf_append(msgdest, hdrline, 80);
|
| 621 |
numdest++;
|
| 622 |
} else if (type == MSG_POST && bufieq(field, "newsgroups")) {
|
| 623 |
memset(hdrline, 0, 80);
|
| 624 |
strcpy(hdrline, "post: ");
|
| 625 |
strcatn(hdrline, content->data, 80);
|
| 626 |
buf_append(msgdest, hdrline, 80);
|
| 627 |
numdest++;
|
| 628 |
} else {
|
| 629 |
buf_clear(header);
|
| 630 |
buf_appendheader(header, field, content);
|
| 631 |
hdr_encode(header, 80);
|
| 632 |
while (buf_getline(header, line) == 0) {
|
| 633 |
/* paste in encoded header entry */
|
| 634 |
memset(hdrline, 0, 80);
|
| 635 |
strncpy(hdrline, line->data, 80);
|
| 636 |
buf_append(msgheader, hdrline, 80);
|
| 637 |
numhdr++;
|
| 638 |
}
|
| 639 |
}
|
| 640 |
}
|
| 641 |
buf_appendc(body, numdest);
|
| 642 |
buf_cat(body, msgdest);
|
| 643 |
buf_appendc(body, numhdr);
|
| 644 |
buf_cat(body, msgheader);
|
| 645 |
|
| 646 |
if (type != MSG_NULL) {
|
| 647 |
buf_rest(temp, message);
|
| 648 |
if (temp->length > 10236 && remailer[chain[0]].flags.compress)
|
| 649 |
buf_compress(temp);
|
| 650 |
buf_cat(body, temp);
|
| 651 |
buf_reset(temp);
|
| 652 |
}
|
| 653 |
buf_setrnd(mid, 16); /* message ID */
|
| 654 |
for (i = 0; i <= body->length / 10236; i++) {
|
| 655 |
long length;
|
| 656 |
|
| 657 |
length = body->length - i * 10236;
|
| 658 |
if (length > 10236)
|
| 659 |
length = 10236;
|
| 660 |
buf_clear(packet);
|
| 661 |
buf_appendl_lo(packet, length);
|
| 662 |
buf_append(packet, body->data + i * 10236, length);
|
| 663 |
buf_pad(packet, 10240);
|
| 664 |
if (send_packet(numcopies, packet, chain, chainlen,
|
| 665 |
i + 1, body->length / 10236 + 1,
|
| 666 |
mid, remailer, badchains, maxrem, NULL, ignore_constraints_if_necessary, feedback) == -1)
|
| 667 |
err = -1;
|
| 668 |
}
|
| 669 |
break;
|
| 670 |
case 3:
|
| 671 |
NOT_IMPLEMENTED;
|
| 672 |
break;
|
| 673 |
default:
|
| 674 |
fprintf(stderr, "%d\n", chain[0]);
|
| 675 |
clienterr(feedback, "Unknown remailer version!");
|
| 676 |
err = -1;
|
| 677 |
}
|
| 678 |
|
| 679 |
end:
|
| 680 |
buf_free(packet);
|
| 681 |
buf_free(line);
|
| 682 |
buf_free(field);
|
| 683 |
buf_free(content);
|
| 684 |
buf_free(header);
|
| 685 |
buf_free(msgheader);
|
| 686 |
buf_free(msgdest);
|
| 687 |
buf_free(body);
|
| 688 |
buf_free(temp);
|
| 689 |
buf_free(mid);
|
| 690 |
return (err);
|
| 691 |
}
|
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