Mix/Src/chain1.c

/* Mixmaster version 2.9  --  (C) 1999 - 2003 Anonymizer Inc. and others.

   Mixmaster may be redistributed and modified under certain conditions.
   This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF
   ANY KIND, either express or implied. See the file COPYRIGHT for
   details.

   Encrypt message for Cypherpunk remailer chain
   $Id$ */

#include "mix.h"
#include "mix3.h"
#ifdef USE_PGP
#       include "pgp.h"
#endif
#include <string.h>
#include <ctype.h>

#define N(X) (isdigit(X) ? (X)-'0' : 0)

int t1_rlist(REMAILER remailer[])
{
  FILE *list;
  int i, listed = 0;
  int n = 0;
  char line[2 * LINELEN], l2[LINELEN], name[LINELEN], *flags;

  list = mix_openfile(TYPE1LIST, "r");
  if (list == NULL)
    return (-1);
  while (fgets(line, sizeof(line), list) != NULL && n < MAXREM) {
    if (strleft(line, "$remailer") &&
        strchr(line, '<') && strchr(line, '>') &&
        strchr(line, '{') && strchr(line, '{') + 4 < strchr(line, '}')) {
      if (line[strlen(line) - 1] == '\n')
        line[strlen(line) - 1] = '\0';
      if (line[strlen(line) - 1] == '\r')
        line[strlen(line) - 1] = '\0';
      while (line[strlen(line) - 1] == ' ')
        line[strlen(line) - 1] = '\0';
      if (line[strlen(line) - 1] != ';'
          && fgets(l2, sizeof(l2), list) != NULL)
        strcatn(line, l2, LINELEN);
      flags = strchr(line, '>');
      strncpy(name, strchr(line, '{') + 2,
              strchr(line, '}') - strchr(line, '{') - 3);
      name[strchr(line, '}') - strchr(line, '{') - 3] = '\0';
      name[20] = '\0';

      for (i = 1; i <= n; i++)
        if (streq(name, remailer[i].name))
          break;
      if (i > n) {
        /* not in mix list */
        n++;
        strcpy(remailer[i].name, name);
        strncpy(remailer[i].addr, strchr(line, '<') + 1,
                strchr(line, '>') - strchr(line, '<'));
        remailer[i].addr[strchr(line, '>') - strchr(line, '<') - 1]
          = '\0';
        remailer[i].flags.mix = 0;
        remailer[i].flags.post = strifind(flags, " post");
      }
      remailer[i].flags.cpunk = strfind(flags, " cpunk");
      remailer[i].flags.pgp = strfind(flags, " pgp");
      remailer[i].flags.pgponly = strfind(flags, " pgponly");
      remailer[i].flags.latent = strfind(flags, " latent");
      remailer[i].flags.middle = strfind(flags, " middle");
      remailer[i].flags.ek = strfind(flags, " ek");
      remailer[i].flags.esub = strfind(flags, " esub");
      remailer[i].flags.newnym = strfind(flags, " newnym");
      remailer[i].flags.nym = strfind(flags, " nym");
      remailer[i].info[1].reliability = 0;
      remailer[i].info[1].latency = 0;
      remailer[i].info[1].history[0] = '\0';
    }
    if (strleft(line,
                "-----------------------------------------------------------------------"))
      break;
  }
  n++;                          /* ?? */
  while (fgets(line, sizeof(line), list) != NULL) {
    if (strlen(line) >= 72 && strlen(line) <= 73)
      for (i = 1; i < n; i++)
        if (strleft(line, remailer[i].name) &&
            line[strlen(remailer[i].name)] == ' ') {
          strncpy(remailer[i].info[1].history, line + 42, 12);
          remailer[i].info[1].history[12] = '\0';
          remailer[i].info[1].reliability = 10000 * N(line[64])
            + 1000 * N(line[65]) + 100 * N(line[66])
            + 10 * N(line[68]) + N(line[69]);
          remailer[i].info[1].latency = 36000 * N(line[55])
            + 3600 * N(line[56]) + 600 * N(line[58])
            + 60 * N(line[59]) + 10 * N(line[61])
            + N(line[62]);
          listed++;
        }
  }
  fclose(list);
  if (listed < 4)               /* we have no valid reliability info */
    for (i = 1; i < n; i++)
      remailer[i].info[1].reliability = 10000;

#ifdef USE_PGP
  pgp_rlist(remailer, n);
#endif /* USE_PGP */
  return (n);
}

int t1_ek(BUFFER *key, BUFFER *seed, int num)
{
  buf_reset(key);
  buf_appendc(key, (byte) num);
  buf_cat(key, seed);
  digest_md5(key, key);
  encode(key, 0);
#ifdef DEBUG
  fprintf(stderr, "passphrase=%s (%2X%2X%2X%2X %d)\n", key->data,
          seed->data[0], seed->data[1], seed->data[2], seed->data[3], num);
#endif /* DEBUG */
  return (0);
}

int t1_encrypt(int type, BUFFER *message, char *chainstr, int latency,
               BUFFER *ek, BUFFER *feedback)
{
  BUFFER *b, *rem, *dest, *line, *field, *content;
  REMAILER remailer[MAXREM];
  int maxrem, chainlen = 0;
  int chain[20];
  int hop;
  int hashmark = 0;
  int err = 0;

  b = buf_new();
  rem = buf_new();
  dest = buf_new();
  line = buf_new();
  field = buf_new();
  content = buf_new();

  maxrem = t1_rlist(remailer);
  if (maxrem < 1) {
    clienterr(feedback, "No remailer list!");
    err = -1;
    goto end;
  }
  chainlen = chain_select(chain, chainstr, maxrem, remailer, 1, line);
  if (chainlen < 1) {
    if (line->length)
      clienterr(feedback, line->data);
    else
      clienterr(feedback, "Invalid remailer chain!");
    err = -1;
    goto end;
  }
  if (chain[0] == 0)
    chain[0] = chain_randfinal(type, remailer, maxrem, 1);

  if (chain[0] == -1) {
    clienterr(feedback, "Invalid remailer chain!");
    err = -1;
    goto end;
  }
  if (chain_rand(remailer, maxrem, chain, chainlen, 1) == -1) {
    clienterr(feedback, "No reliable remailers!");
    err = -1;
    goto end;
  }
  while (buf_getheader(message, field, content) == 0) {
    hdr_encode(content, 0);
    if (type == MSG_POST && bufieq(field, "newsgroups") &&
        remailer[chain[0]].flags.post) {
      buf_appendf(dest, "Anon-Post-To: %b\n", content);
    } else if (type == MSG_MAIL && bufieq(field, "to")) {
      buf_appendf(dest, "Anon-To: %b\n", content);
    } else {
      /* paste header */
      if (type == MSG_POST && bufieq(field, "newsgroups"))
        buf_appendf(dest, "Anon-To: %s\n", MAILtoNEWS);
      if (hashmark == 0) {
        buf_appends(b, "##\n");
        hashmark = 1;
      }
      buf_appendheader(b, field, content);
    }
  }
  buf_nl(b);
  buf_rest(b, message);
  buf_move(message, b);

  if (type != MSG_NULL && dest->length == 0) {
    clienterr(feedback, "No destination address!");
    err = -1;
    goto end;
  }
  if (type == MSG_NULL) {
    buf_sets(dest, "Null:\n");
  }
  for (hop = 0; hop < chainlen; hop++) {
    if (hop == 0) {
      buf_sets(b, "::\n");
      buf_cat(b, dest);
    } else {
      buf_sets(b, "::\nAnon-To: ");
      buf_appends(b, remailer[chain[hop - 1]].addr);
      buf_nl(b);
    }
    if (remailer[chain[hop]].flags.latent && latency > 0)
      buf_appendf(b, "Latent-Time: +%d:00r\n", latency);
    if (ek && remailer[chain[hop]].flags.ek) {
      t1_ek(line, ek, hop);
      buf_appendf(b, "Encrypt-Key: %b\n", line);
    }
    buf_nl(b);
    buf_cat(b, message);
#ifdef USE_PGP
    if (remailer[chain[hop]].flags.pgp) {
      buf_clear(message);
      buf_clear(rem);
      buf_setf(rem, "<%s>", remailer[chain[hop]].addr);
      err = pgp_encrypt(PGP_ENCRYPT | PGP_REMAIL | PGP_TEXT, b, rem,
                        NULL, NULL, NULL, NULL);
      if (err < 0) {
        buf_setf(line, "No PGP key for remailer %s!\n",
                 remailer[chain[hop]].name);
        clienterr(feedback, line->data);
        goto end;
      }
      buf_appends(message, "::\nEncrypted: PGP\n\n");
      buf_cat(message, b);
    } else
#endif /* USE_PGP */
    {
      if (remailer[chain[hop]].flags.pgponly) {
        buf_setf(line, "PGP encryption needed for remailer %s!\n",
                 remailer[chain[hop]].name);
        clienterr(feedback, line->data);
        goto end;
      }
      buf_move(message, b);
    }
    if (ek && remailer[chain[hop]].flags.ek)
      buf_appends(message, "\n**\n");
  }
  buf_clear(b);
  if (chainlen == 0) {
    buf_appends(b, "::\n");
    buf_cat(b, dest);
  } else {
    buf_appendf(b, "%s: %s\n", ek ? "::\nAnon-To" : "To",
                remailer[chain[chainlen - 1]].addr);
  }
  buf_nl(b);
  buf_cat(b, message);
  buf_move(message, b);
end:
  buf_free(b);
  buf_free(rem);
  buf_free(dest);
  buf_free(line);
  buf_free(field);
  buf_free(content);
  return (err);
}

#ifdef USE_PGP
int t1_getreply(BUFFER *msg, BUFFER *ek, int len)
{
  BUFFER *key, *decrypt;
  int err = -1;
  int hop = 0;

  key = buf_new();
  decrypt = buf_new();

  do {
    t1_ek(key, ek, hop);
    buf_set(decrypt, msg);
    if (pgp_decrypt(decrypt, key, NULL, NULL, NULL) == 0
        && decrypt->data != NULL)
      err = 0, buf_move(msg, decrypt);
  }
  while (hop++ < len);
  return (err);
}

#endif /* USE_PGP */
1	/* Mixmaster version 2.9 -- (C) 1999 - 2003 Anonymizer Inc. and others.
2
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.
7
8	Encrypt message for Cypherpunk remailer chain
9	$Id$ */
10
11	#include "mix.h"
12	#include "mix3.h"
13	#ifdef USE_PGP
14	# include "pgp.h"
15	#endif
16	#include <string.h>
17	#include <ctype.h>
18
19	#define N(X) (isdigit(X) ? (X)-'0' : 0)
20
21	int t1_rlist(REMAILER remailer[])
22	{
23	FILE *list;
24	int i, listed = 0;
25	int n = 0;
26	char line[2 * LINELEN], l2[LINELEN], name[LINELEN], *flags;
27
28	list = mix_openfile(TYPE1LIST, "r");
29	if (list == NULL)
30	return (-1);
31	while (fgets(line, sizeof(line), list) != NULL && n < MAXREM) {
32	if (strleft(line, "$remailer") &&
33	strchr(line, '<') && strchr(line, '>') &&
34	strchr(line, '{') && strchr(line, '{') + 4 < strchr(line, '}')) {
35	if (line[strlen(line) - 1] == '\n')
36	line[strlen(line) - 1] = '\0';
37	if (line[strlen(line) - 1] == '\r')
38	line[strlen(line) - 1] = '\0';
39	while (line[strlen(line) - 1] == ' ')
40	line[strlen(line) - 1] = '\0';
41	if (line[strlen(line) - 1] != ';'
42	&& fgets(l2, sizeof(l2), list) != NULL)
43	strcatn(line, l2, LINELEN);
44	flags = strchr(line, '>');
45	strncpy(name, strchr(line, '{') + 2,
46	strchr(line, '}') - strchr(line, '{') - 3);
47	name[strchr(line, '}') - strchr(line, '{') - 3] = '\0';
48	name[20] = '\0';
49
50	for (i = 1; i <= n; i++)
51	if (streq(name, remailer[i].name))
52	break;
53	if (i > n) {
54	/* not in mix list */
55	n++;
56	strcpy(remailer[i].name, name);
57	strncpy(remailer[i].addr, strchr(line, '<') + 1,
58	strchr(line, '>') - strchr(line, '<'));
59	remailer[i].addr[strchr(line, '>') - strchr(line, '<') - 1]
60	= '\0';
61	remailer[i].flags.mix = 0;
62	remailer[i].flags.post = strifind(flags, " post");
63	}
64	remailer[i].flags.cpunk = strfind(flags, " cpunk");
65	remailer[i].flags.pgp = strfind(flags, " pgp");
66	remailer[i].flags.pgponly = strfind(flags, " pgponly");
67	remailer[i].flags.latent = strfind(flags, " latent");
68	remailer[i].flags.middle = strfind(flags, " middle");
69	remailer[i].flags.ek = strfind(flags, " ek");
70	remailer[i].flags.esub = strfind(flags, " esub");
71	remailer[i].flags.newnym = strfind(flags, " newnym");
72	remailer[i].flags.nym = strfind(flags, " nym");
73	remailer[i].info[1].reliability = 0;
74	remailer[i].info[1].latency = 0;
75	remailer[i].info[1].history[0] = '\0';
76	}
77	if (strleft(line,
78	"-----------------------------------------------------------------------"))
79	break;
80	}
81	n++; /* ?? */
82	while (fgets(line, sizeof(line), list) != NULL) {
83	if (strlen(line) >= 72 && strlen(line) <= 73)
84	for (i = 1; i < n; i++)
85	if (strleft(line, remailer[i].name) &&
86	line[strlen(remailer[i].name)] == ' ') {
87	strncpy(remailer[i].info[1].history, line + 42, 12);
88	remailer[i].info[1].history[12] = '\0';
89	remailer[i].info[1].reliability = 10000 * N(line[64])
90	+ 1000 * N(line[65]) + 100 * N(line[66])
91	+ 10 * N(line[68]) + N(line[69]);
92	remailer[i].info[1].latency = 36000 * N(line[55])
93	+ 3600 * N(line[56]) + 600 * N(line[58])
94	+ 60 * N(line[59]) + 10 * N(line[61])
95	+ N(line[62]);
96	listed++;
97	}
98	}
99	fclose(list);
100	if (listed < 4) /* we have no valid reliability info */
101	for (i = 1; i < n; i++)
102	remailer[i].info[1].reliability = 10000;
103
104	#ifdef USE_PGP
105	pgp_rlist(remailer, n);
106	#endif /* USE_PGP */
107	return (n);
108	}
109
110	int t1_ek(BUFFER key, BUFFER seed, int num)
111	{
112	buf_reset(key);
113	buf_appendc(key, (byte) num);
114	buf_cat(key, seed);
115	digest_md5(key, key);
116	encode(key, 0);
117	#ifdef DEBUG
118	fprintf(stderr, "passphrase=%s (%2X%2X%2X%2X %d)\n", key->data,
119	seed->data[0], seed->data[1], seed->data[2], seed->data[3], num);
120	#endif /* DEBUG */
121	return (0);
122	}
123
124	int t1_encrypt(int type, BUFFER message, char chainstr, int latency,
125	BUFFER ek, BUFFER feedback)
126	{
127	BUFFER b, rem, dest, line, field, content;
128	REMAILER remailer[MAXREM];
129	int maxrem, chainlen = 0;
130	int chain[20];
131	int hop;
132	int hashmark = 0;
133	int err = 0;
134
135	b = buf_new();
136	rem = buf_new();
137	dest = buf_new();
138	line = buf_new();
139	field = buf_new();
140	content = buf_new();
141
142	maxrem = t1_rlist(remailer);
143	if (maxrem < 1) {
144	clienterr(feedback, "No remailer list!");
145	err = -1;
146	goto end;
147	}
148	chainlen = chain_select(chain, chainstr, maxrem, remailer, 1, line);
149	if (chainlen < 1) {
150	if (line->length)
151	clienterr(feedback, line->data);
152	else
153	clienterr(feedback, "Invalid remailer chain!");
154	err = -1;
155	goto end;
156	}
157	if (chain[0] == 0)
158	chain[0] = chain_randfinal(type, remailer, maxrem, 1);
159
160	if (chain[0] == -1) {
161	clienterr(feedback, "Invalid remailer chain!");
162	err = -1;
163	goto end;
164	}
165	if (chain_rand(remailer, maxrem, chain, chainlen, 1) == -1) {
166	clienterr(feedback, "No reliable remailers!");
167	err = -1;
168	goto end;
169	}
170	while (buf_getheader(message, field, content) == 0) {
171	hdr_encode(content, 0);
172	if (type == MSG_POST && bufieq(field, "newsgroups") &&
173	remailer[chain[0]].flags.post) {
174	buf_appendf(dest, "Anon-Post-To: %b\n", content);
175	} else if (type == MSG_MAIL && bufieq(field, "to")) {
176	buf_appendf(dest, "Anon-To: %b\n", content);
177	} else {
178	/* paste header */
179	if (type == MSG_POST && bufieq(field, "newsgroups"))
180	buf_appendf(dest, "Anon-To: %s\n", MAILtoNEWS);
181	if (hashmark == 0) {
182	buf_appends(b, "##\n");
183	hashmark = 1;
184	}
185	buf_appendheader(b, field, content);
186	}
187	}
188	buf_nl(b);
189	buf_rest(b, message);
190	buf_move(message, b);
191
192	if (type != MSG_NULL && dest->length == 0) {
193	clienterr(feedback, "No destination address!");
194	err = -1;
195	goto end;
196	}
197	if (type == MSG_NULL) {
198	buf_sets(dest, "Null:\n");
199	}
200	for (hop = 0; hop < chainlen; hop++) {
201	if (hop == 0) {
202	buf_sets(b, "::\n");
203	buf_cat(b, dest);
204	} else {
205	buf_sets(b, "::\nAnon-To: ");
206	buf_appends(b, remailer[chain[hop - 1]].addr);
207	buf_nl(b);
208	}
209	if (remailer[chain[hop]].flags.latent && latency > 0)
210	buf_appendf(b, "Latent-Time: +%d:00r\n", latency);
211	if (ek && remailer[chain[hop]].flags.ek) {
212	t1_ek(line, ek, hop);
213	buf_appendf(b, "Encrypt-Key: %b\n", line);
214	}
215	buf_nl(b);
216	buf_cat(b, message);
217	#ifdef USE_PGP
218	if (remailer[chain[hop]].flags.pgp) {
219	buf_clear(message);
220	buf_clear(rem);
221	buf_setf(rem, "<%s>", remailer[chain[hop]].addr);
222	err = pgp_encrypt(PGP_ENCRYPT \| PGP_REMAIL \| PGP_TEXT, b, rem,
223	NULL, NULL, NULL, NULL);
224	if (err < 0) {
225	buf_setf(line, "No PGP key for remailer %s!\n",
226	remailer[chain[hop]].name);
227	clienterr(feedback, line->data);
228	goto end;
229	}
230	buf_appends(message, "::\nEncrypted: PGP\n\n");
231	buf_cat(message, b);
232	} else
233	#endif /* USE_PGP */
234	{
235	if (remailer[chain[hop]].flags.pgponly) {
236	buf_setf(line, "PGP encryption needed for remailer %s!\n",
237	remailer[chain[hop]].name);
238	clienterr(feedback, line->data);
239	goto end;
240	}
241	buf_move(message, b);
242	}
243	if (ek && remailer[chain[hop]].flags.ek)
244	buf_appends(message, "\n**\n");
245	}
246	buf_clear(b);
247	if (chainlen == 0) {
248	buf_appends(b, "::\n");
249	buf_cat(b, dest);
250	} else {
251	buf_appendf(b, "%s: %s\n", ek ? "::\nAnon-To" : "To",
252	remailer[chain[chainlen - 1]].addr);
253	}
254	buf_nl(b);
255	buf_cat(b, message);
256	buf_move(message, b);
257	end:
258	buf_free(b);
259	buf_free(rem);
260	buf_free(dest);
261	buf_free(line);
262	buf_free(field);
263	buf_free(content);
264	return (err);
265	}
266
267	#ifdef USE_PGP
268	int t1_getreply(BUFFER msg, BUFFER ek, int len)
269	{
270	BUFFER key, decrypt;
271	int err = -1;
272	int hop = 0;
273
274	key = buf_new();
275	decrypt = buf_new();
276
277	do {
278	t1_ek(key, ek, hop);
279	buf_set(decrypt, msg);
280	if (pgp_decrypt(decrypt, key, NULL, NULL, NULL) == 0
281	&& decrypt->data != NULL)
282	err = 0, buf_move(msg, decrypt);
283	}
284	while (hop++ < len);
285	return (err);
286	}
287
288	#endif /* USE_PGP */