2 * popsbr.c -- POP client subroutines
6 * This code is Copyright (c) 2002, by the authors of nmh. See the
7 * COPYRIGHT file in the root directory of the nmh distribution for
8 * complete copyright information.
13 extern int client(char *args, char *protocol, char *service, int rproto,
14 char *response, int len_response);
16 #if defined(NNTP) && !defined(PSHSBR)
20 #ifdef NNTP /* building pshsbr.o from popsbr.c */
24 #if !defined(NNTP) && defined(APOP)
30 #endif /* CYRUS_SASL */
33 #include <h/signals.h>
38 #define TRMLEN (sizeof TRM - 1)
40 static int poprint = 0;
41 static int pophack = 0;
43 char response[BUFSIZ];
50 #if !defined(NNTP) && defined(MPOP)
51 # define command pop_command
52 # define multiline pop_multiline
56 # ifdef BPOP /* stupid */
57 static int xtnd_last = -1;
58 static int xtnd_first = 0;
59 static char xtnd_name[512]; /* INCREDIBLE HACK!! */
64 static sasl_conn_t *conn; /* SASL connection state */
65 static int sasl_complete = 0; /* Has sasl authentication succeeded? */
66 static int maxoutbuf; /* Maximum output buffer size */
67 static sasl_ssf_t sasl_ssf = 0; /* Security strength factor */
68 static int sasl_get_user(void *, int, const char **, unsigned *);
69 static int sasl_get_pass(sasl_conn_t *, void *, int, sasl_secret_t **);
75 static sasl_callback_t callbacks[] = {
76 { SASL_CB_USER, sasl_get_user, NULL },
77 #define POP_SASL_CB_N_USER 0
78 { SASL_CB_PASS, sasl_get_pass, NULL },
79 #define POP_SASL_CB_N_PASS 1
80 { SASL_CB_LIST_END, NULL, NULL },
82 #else /* CYRUS_SASL */
83 # define sasl_fgetc fgetc
84 #endif /* CYRUS_SASL */
89 #if !defined(NNTP) && defined(APOP)
90 static char *pop_auth (char *, char *);
93 #if defined(NNTP) || !defined(MPOP)
94 /* otherwise they are not static functions */
95 static int command(const char *, ...);
96 static int multiline(void);
100 static int pop_auth_sasl(char *, char *, char *);
101 static int sasl_fgetc(FILE *);
102 #endif /* CYRUS_SASL */
104 static int traverse (int (*)(), const char *, ...);
105 static int vcommand(const char *, va_list);
106 static int getline (char *, int, FILE *);
107 static int putline (char *, FILE *);
110 #if !defined(NNTP) && defined(APOP)
112 pop_auth (char *user, char *pass)
116 unsigned char *dp, *ep, digest[16];
118 static char buffer[BUFSIZ];
120 if ((cp = strchr (response, '<')) == NULL
121 || (lp = strchr (cp, '>')) == NULL) {
122 snprintf (buffer, sizeof(buffer), "APOP not available: %s", response);
123 strncpy (response, buffer, sizeof(response));
128 snprintf (buffer, sizeof(buffer), "%s%s", cp, pass);
130 MD5Init (&mdContext);
131 MD5Update (&mdContext, (unsigned char *) buffer,
132 (unsigned int) strlen (buffer));
133 MD5Final (digest, &mdContext);
136 buflen = sizeof(buffer);
138 snprintf (cp, buflen, "%s ", user);
143 for (ep = (dp = digest) + sizeof(digest) / sizeof(digest[0]); dp < ep; ) {
144 snprintf (cp, buflen, "%02x", *dp++ & 0xff);
152 #endif /* !NNTP && APOP */
156 * This function implements the AUTH command for various SASL mechanisms
158 * We do the whole SASL dialog here. If this completes, then we've
159 * authenticated successfully and have (possibly) negotiated a security
164 pop_auth_sasl(char *user, char *host, char *mech)
166 int result, status, sasl_capability = 0, outlen;
168 char server_mechs[256], *buf, outbuf[BUFSIZ];
169 const char *chosen_mech;
170 sasl_security_properties_t secprops;
171 sasl_external_properties_t extprops;
172 struct pass_context p_context;
177 * First off, we're going to send the CAPA command to see if we can
178 * even support the AUTH command, and if we do, then we'll get a
179 * list of mechanisms the server supports. If we don't support
180 * the CAPA command, then it's unlikely that we will support
184 if (command("CAPA") == NOTOK) {
185 snprintf(response, sizeof(response),
186 "The POP CAPA command failed; POP server does not "
191 while ((status = multiline()) != DONE)
196 case DONE: /* Shouldn't be possible, but just in case */
199 if (strncasecmp(response, "SASL ", 5) == 0) {
201 * We've seen the SASL capability. Grab the mech list
204 strncpy(server_mechs, response + 5, sizeof(server_mechs));
209 if (!sasl_capability) {
210 snprintf(response, sizeof(response), "POP server does not support "
216 * If we received a preferred mechanism, see if the server supports it.
219 if (mech && stringdex(mech, server_mechs) == -1) {
220 snprintf(response, sizeof(response), "Requested SASL mech \"%s\" is "
221 "not in list of supported mechanisms:\n%s",
227 * Start the SASL process. First off, initialize the SASL library.
230 callbacks[POP_SASL_CB_N_USER].context = user;
231 p_context.user = user;
232 p_context.host = host;
233 callbacks[POP_SASL_CB_N_PASS].context = &p_context;
235 result = sasl_client_init(callbacks);
237 if (result != SASL_OK) {
238 snprintf(response, sizeof(response), "SASL library initialization "
239 "failed: %s", sasl_errstring(result, NULL, NULL));
243 result = sasl_client_new("pop", host, NULL, SASL_SECURITY_LAYER, &conn);
245 if (result != SASL_OK) {
246 snprintf(response, sizeof(response), "SASL client initialization "
247 "failed: %s", sasl_errstring(result, NULL, NULL));
252 * Initialize the security properties
255 memset(&secprops, 0, sizeof(secprops));
256 secprops.maxbufsize = BUFSIZ;
257 secprops.max_ssf = UINT_MAX;
258 memset(&extprops, 0, sizeof(extprops));
260 result = sasl_setprop(conn, SASL_SEC_PROPS, &secprops);
262 if (result != SASL_OK) {
263 snprintf(response, sizeof(response), "SASL security property "
264 "initialization failed: %s",
265 sasl_errstring(result, NULL, NULL));
269 result = sasl_setprop(conn, SASL_SSF_EXTERNAL, &extprops);
271 if (result != SASL_OK) {
272 snprintf(response, sizeof(response), "SASL external property "
273 "initialization failed: %s",
274 sasl_errstring(result, NULL, NULL));
279 * Start the actual protocol. Feed the mech list into the library
280 * and get out a possible initial challenge
283 result = sasl_client_start(conn, mech ? mech : server_mechs,
284 NULL, NULL, &buf, &buflen, &chosen_mech);
286 if (result != SASL_OK && result != SASL_CONTINUE) {
287 snprintf(response, sizeof(response), "SASL client start failed: %s",
288 sasl_errstring(result, NULL, NULL));
293 status = sasl_encode64(buf, buflen, outbuf, sizeof(outbuf), NULL);
295 if (status != SASL_OK) {
296 snprintf(response, sizeof(response), "SASL base64 encode "
297 "failed: %s", sasl_errstring(status, NULL, NULL));
301 status = command("AUTH %s %s", chosen_mech, outbuf);
303 status = command("AUTH %s", chosen_mech);
305 while (result == SASL_CONTINUE) {
310 * If we get a "+OK" prefix to our response, then we should
311 * exit out of this exchange now (because authenticated should
315 if (strncmp(response, "+OK", 3) == 0)
319 * Otherwise, make sure the server challenge is correctly formatted
322 if (strncmp(response, "+ ", 2) != 0) {
324 snprintf(response, sizeof(response),
325 "Malformed authentication message from server");
329 result = sasl_decode64(response + 2, strlen(response + 2),
332 if (result != SASL_OK) {
334 snprintf(response, sizeof(response), "SASL base64 decode "
335 "failed: %s", sasl_errstring(result, NULL, NULL));
339 result = sasl_client_step(conn, outbuf, outlen, NULL, &buf, &buflen);
341 if (result != SASL_OK && result != SASL_CONTINUE) {
343 snprintf(response, sizeof(response), "SASL client negotiaton "
344 "failed: %s", sasl_errstring(result, NULL, NULL));
348 status = sasl_encode64(buf, buflen, outbuf, sizeof(outbuf), NULL);
351 if (status != SASL_OK) {
353 snprintf(response, sizeof(response), "SASL base64 encode "
354 "failed: %s", sasl_errstring(status, NULL, NULL));
358 status = command(outbuf);
362 * If we didn't get a positive final response, then error out
363 * (that probably means we failed an authorization check).
370 * Depending on the mechanism, we might need to call sasl_client_step()
371 * one more time. Do that now.
374 result = sasl_client_step(conn, NULL, 0, NULL, &buf, &buflen);
376 if (result != SASL_OK) {
377 snprintf(response, sizeof(response), "SASL final client negotiaton "
378 "failed: %s", sasl_errstring(result, NULL, NULL));
383 * We _should_ be okay now. Get a few properties now that negotiation
387 result = sasl_getprop(conn, SASL_MAXOUTBUF, (void **) &moutbuf);
389 if (result != SASL_OK) {
390 snprintf(response, sizeof(response), "Cannot retrieve SASL negotiated "
391 "output buffer size: %s", sasl_errstring(result, NULL, NULL));
395 maxoutbuf = *moutbuf;
397 result = sasl_getprop(conn, SASL_SSF, (void **) &ssf);
401 if (result != SASL_OK) {
402 snprintf(response, sizeof(response), "Cannot retrieve SASL negotiated "
403 "security strength factor: %s",
404 sasl_errstring(result, NULL, NULL));
409 * Limit this to what we can deal with.
412 if (maxoutbuf == 0 || maxoutbuf > BUFSIZ)
421 * Callback to return the userid sent down via the user parameter
425 sasl_get_user(void *context, int id, const char **result, unsigned *len)
427 char *user = (char *) context;
429 if (! result || id != SASL_CB_USER)
430 return SASL_BADPARAM;
440 * Callback to return the password (we call ruserpass, which can get it
445 sasl_get_pass(sasl_conn_t *conn, void *context, int id, sasl_secret_t **psecret)
447 struct pass_context *p_context = (struct pass_context *) context;
451 if (! psecret || id != SASL_CB_PASS)
452 return SASL_BADPARAM;
454 ruserpass(p_context->user, &(p_context->host), &pass);
458 *psecret = (sasl_secret_t *) malloc(sizeof(sasl_secret_t) + len);
463 (*psecret)->len = len;
464 strcpy((*psecret)->data, pass);
468 #endif /* CYRUS_SASL */
471 pop_init (char *host, char *user, char *pass, int snoop, int rpop, int kpop,
472 int sasl, char *mech)
480 if ((apop = rpop) < 0)
487 snprintf (buffer, sizeof(buffer), "%s/%s", KPOP_PRINCIPAL, "kpop");
488 if ((fd1 = client (host, "tcp", buffer, 0, response, sizeof(response))) == NOTOK) {
493 if ((fd1 = client (host, "tcp", POPSERVICE, rpop, response, sizeof(response))) == NOTOK) {
500 if ((fd1 = client (host, "tcp", "nntp", rpop, response, sizeof(response))) == NOTOK)
504 if ((fd2 = dup (fd1)) == NOTOK) {
507 if ((s = strerror(errno)))
508 snprintf (response, sizeof(response),
509 "unable to dup connection descriptor: %s", s);
511 snprintf (response, sizeof(response),
512 "unable to dup connection descriptor: unknown error");
517 if (pop_set (fd1, fd2, snoop) == NOTOK)
519 if (pop_set (fd1, fd2, snoop, (char *)0) == NOTOK)
523 SIGNAL (SIGPIPE, SIG_IGN);
525 switch (getline (response, sizeof response, input)) {
528 fprintf (stderr, "<--- %s\n", response);
530 if (*response == '+') {
534 char *cp = pop_auth (user, pass);
536 if (cp && command ("APOP %s", cp) != NOTOK)
543 if (pop_auth_sasl(user, host, mech) != NOTOK)
546 # endif /* CYRUS_SASL */
547 if (command ("USER %s", user) != NOTOK
548 && command ("%s %s", rpop ? "RPOP" : (pophack++, "PASS"),
552 if (command ("USER %s", user) != NOTOK
553 && command ("PASS %s", pass) != NOTOK)
558 if (*response < CHAR_ERR) {
559 command ("MODE READER");
563 strncpy (buffer, response, sizeof(buffer));
565 strncpy (response, buffer, sizeof(response));
571 fprintf (stderr, "%s\n", response);
577 return NOTOK; /* NOTREACHED */
582 pop_set (int in, int out, int snoop, char *myname)
585 pop_set (int in, int out, int snoop)
590 if (myname && *myname) {
591 /* interface from bbc to msh */
592 strncpy (xtnd_name, myname, sizeof(xtnd_name));
596 if ((input = fdopen (in, "r")) == NULL
597 || (output = fdopen (out, "w")) == NULL) {
598 strncpy (response, "fdopen failed on connection descriptor", sizeof(response));
614 pop_fd (char *in, int inlen, char *out, int outlen)
616 snprintf (in, inlen, "%d", fileno (input));
617 snprintf (out, outlen, "%d", fileno (output));
623 * Find out number of messages available
624 * and their total size.
628 pop_stat (int *nmsgs, int *nbytes)
635 if (command ("STAT") == NOTOK)
638 *nmsgs = *nbytes = 0;
639 sscanf (response, "+OK %d %d", nmsgs, nbytes);
642 if (xtnd_last < 0) { /* in msh, xtnd_name is set from myname */
643 if (command("GROUP %s", xtnd_name) == NOTOK)
646 ap = brkstring (response, " ", "\n"); /* "211 nart first last ggg" */
647 xtnd_first = atoi (ap[2]);
648 xtnd_last = atoi (ap[3]);
651 /* nmsgs is not the real nart, but an incredible simuation */
653 *nmsgs = xtnd_last - xtnd_first + 1; /* because of holes... */
656 *nbytes = xtnd_first; /* for subtracting offset in msh() */
664 pop_exists (int (*action)())
666 #ifdef XMSGS /* hacked into NNTP 1.5 */
667 if (traverse (action, "XMSGS %d-%d", (targ_t) xtnd_first, (targ_t) xtnd_last) == OK)
670 /* provided by INN 1.4 */
671 if (traverse (action, "LISTGROUP") == OK)
673 return traverse (action, "XHDR NONAME %d-%d", (targ_t) xtnd_first, (targ_t) xtnd_last);
680 pop_list (int msgno, int *nmsgs, int *msgs, int *bytes, int *ids)
683 pop_list (int msgno, int *nmsgs, int *msgs, int *bytes)
693 if (command ("LIST %d", msgno) == NOTOK)
698 sscanf (response, "+OK %d %d %d", msgs, bytes, ids);
701 sscanf (response, "+OK %d %d", msgs, bytes);
704 if (command ("STAT %d", msgno) == NOTOK)
714 if (command ("LIST") == NOTOK)
717 for (i = 0; i < *nmsgs; i++)
718 switch (multiline ()) {
728 sscanf (response, "%d %d %d",
729 msgs++, bytes++, ids++);
732 sscanf (response, "%d %d", msgs++, bytes++);
736 switch (multiline ()) {
751 pop_retr (int msgno, int (*action)())
754 return traverse (action, "RETR %d", (targ_t) msgno);
756 return traverse (action, "ARTICLE %d", (targ_t) msgno);
762 traverse (int (*action)(), const char *fmt, ...)
766 char buffer[sizeof(response)];
769 result = vcommand (fmt, ap);
774 strncpy (buffer, response, sizeof(buffer));
777 switch (multiline ()) {
782 strncpy (response, buffer, sizeof(response));
786 (*action) (response);
795 return command ("DELE %d", msgno);
802 return command ("NOOP");
806 #if defined(MPOP) && !defined(NNTP)
810 return command ("LAST");
818 return command ("RSET");
823 pop_top (int msgno, int lines, int (*action)())
826 return traverse (action, "TOP %d %d", (targ_t) msgno, (targ_t) lines);
828 return traverse (action, "HEAD %d", (targ_t) msgno);
835 pop_xtnd (int (*action)(), char *fmt, ...)
847 /* needs to be fixed... va_end needs to be added */
848 snprintf (buffer, sizeof(buffer), "XTND %s", fmt);
849 result = traverse (action, buffer, a, b, c, d);
853 snprintf (buffer, sizeof(buffer), fmt, a, b, c, d);
854 ap = brkstring (buffer, " ", "\n"); /* a hack, i know... */
856 if (!strcasecmp(ap[0], "x-bboards")) { /* XTND "X-BBOARDS group */
857 /* most of these parameters are meaningless under NNTP.
858 * bbc.c was modified to set AKA and LEADERS as appropriate,
859 * the rest are left blank.
863 if (!strcasecmp (ap[0], "archive") && ap[1]) {
864 snprintf (xtnd_name, sizeof(xtnd_name), "%s", ap[1]); /* save the name */
866 xtnd_first = 1; /* setup to fail in pop_stat */
869 if (!strcasecmp (ap[0], "bboards")) {
871 if (ap[1]) { /* XTND "BBOARDS group" */
872 snprintf (xtnd_name, sizeof(xtnd_name), "%s", ap[1]); /* save the name */
873 if (command("GROUP %s", xtnd_name) == NOTOK)
876 /* action must ignore extra args */
877 strncpy (buffer, response, sizeof(buffer));
878 ap = brkstring (response, " ", "\n");/* "211 nart first last g" */
879 xtnd_first = atoi (ap[2]);
880 xtnd_last = atoi (ap[3]);
885 } else { /* XTND "BBOARDS" */
886 return traverse (action, "LIST", a, b, c, d);
889 return NOTOK; /* unknown XTND command */
900 i = command ("QUIT");
913 #endif /* CYRUS_SASL */
921 #if !defined(MPOP) || defined(NNTP)
925 command(const char *fmt, ...)
931 result = vcommand(fmt, ap);
939 vcommand (const char *fmt, va_list ap)
941 char *cp, buffer[BUFSIZ];
943 vsnprintf (buffer, sizeof(buffer), fmt, ap);
947 fprintf(stderr, "(encrypted) ");
948 #endif /* CYRUS_SASL */
950 if ((cp = strchr (buffer, ' ')))
952 fprintf (stderr, "---> %s ********\n", buffer);
958 fprintf (stderr, "---> %s\n", buffer);
961 if (putline (buffer, output) == NOTOK)
965 if (poprint && sasl_ssf)
966 fprintf(stderr, "(decrypted) ");
967 #endif /* CYRUS_SASL */
969 switch (getline (response, sizeof response, input)) {
972 fprintf (stderr, "<--- %s\n", response);
974 return (*response == '+' ? OK : NOTOK);
976 return (*response < CHAR_ERR ? OK : NOTOK);
982 fprintf (stderr, "%s\n", response);
986 return NOTOK; /* NOTREACHED */
990 #if defined(MPOP) && !defined(NNTP)
998 char buffer[BUFSIZ + TRMLEN];
1000 if (getline (buffer, sizeof buffer, input) != OK)
1006 fprintf(stderr, "(decrypted) ");
1007 #endif /* CYRUS_SASL */
1008 fprintf (stderr, "<--- %s\n", response);
1011 if (strncmp (buffer, TRM, TRMLEN) == 0) {
1012 if (buffer[TRMLEN] == 0)
1015 strncpy (response, buffer + TRMLEN, sizeof(response));
1018 strncpy (response, buffer, sizeof(response));
1024 * Note that these functions have been modified to deal with layer encryption
1029 getline (char *s, int n, FILE *iop)
1035 while (--n > 0 && (c = sasl_fgetc (iop)) != EOF && c != -2)
1036 if ((*p++ = c) == '\n')
1040 if (ferror (iop) && c != EOF) {
1041 strncpy (response, "error on connection", sizeof(response));
1044 if (c == EOF && p == s) {
1045 strncpy (response, "connection closed by foreign host", sizeof(response));
1059 putline (char *s, FILE *iop)
1062 char outbuf[BUFSIZ], *buf;
1064 unsigned int buflen;
1066 if (!sasl_complete) {
1067 #endif /* CYRUS_SASL */
1068 fprintf (iop, "%s\r\n", s);
1072 * Build an output buffer, encrypt it using sasl_encode, and
1073 * squirt out the results.
1075 strncpy(outbuf, s, sizeof(outbuf) - 3);
1076 outbuf[sizeof(outbuf) - 3] = '\0'; /* Just in case */
1077 strcat(outbuf, "\r\n");
1079 result = sasl_encode(conn, outbuf, strlen(outbuf), &buf, &buflen);
1081 if (result != SASL_OK) {
1082 snprintf(response, sizeof(response), "SASL encoding error: %s",
1083 sasl_errstring(result, NULL, NULL));
1087 fwrite(buf, buflen, 1, iop);
1090 #endif /* CYRUS_SASL */
1094 strncpy (response, "lost connection", sizeof(response));
1103 * Okay, our little fgetc replacement. Hopefully this is a little more
1104 * efficient than the last one.
1109 static unsigned char *buffer = NULL, *ptr;
1110 static int size = 0;
1112 unsigned int retbufsize = 0;
1114 char *retbuf, tmpbuf[BUFSIZ];
1117 * If we have some leftover data, return that
1122 return (int) *ptr++;
1126 * Otherwise, fill our buffer until we have some data to return.
1129 while (retbufsize == 0) {
1131 cc = read(fileno(f), tmpbuf, sizeof(tmpbuf));
1137 snprintf(response, sizeof(response), "Error during read from "
1138 "network: %s", strerror(errno));
1143 * We're not allowed to call sasl_decode until sasl_complete is
1144 * true, so we do these gyrations ...
1147 if (!sasl_complete) {
1154 result = sasl_decode(conn, tmpbuf, cc, &retbuf, &retbufsize);
1156 if (result != SASL_OK) {
1157 snprintf(response, sizeof(response), "Error during SASL "
1158 "decoding: %s", sasl_errstring(result, NULL, NULL));
1164 if (retbufsize > size) {
1165 buffer = realloc(buffer, retbufsize);
1167 snprintf(response, sizeof(response), "Error during realloc in "
1168 "read routine: %s", strerror(errno));
1174 memcpy(buffer, retbuf, retbufsize);
1176 cnt = retbufsize - 1;
1180 return (int) buffer[0];
1182 #endif /* CYRUS_SASL */