2 * Copyright (c) 1998, 1999 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
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27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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35 #include "ftpd_locl.h"
40 RCSID("$Id: security.c,v 1.15 1999/12/02 16:58:30 joda Exp $");
42 static enum protection_level command_prot;
43 static enum protection_level data_prot;
44 static size_t buffer_size;
53 static struct buffer in_buffer, out_buffer;
57 enum protection_level level;
60 { prot_clear, "clear" },
61 { prot_safe, "safe" },
62 { prot_confidential, "confidential" },
63 { prot_private, "private" }
67 level_to_name(enum protection_level level)
70 for(i = 0; i < sizeof(level_names) / sizeof(level_names[0]); i++)
71 if(level_names[i].level == level)
72 return level_names[i].name;
76 #ifndef FTP_SERVER /* not used in server */
77 static enum protection_level
78 name_to_level(const char *name)
81 for(i = 0; i < sizeof(level_names) / sizeof(level_names[0]); i++)
82 if(!strncasecmp(level_names[i].name, name, strlen(name)))
83 return level_names[i].level;
84 return (enum protection_level)-1;
90 static struct sec_server_mech *mechs[] = {
100 static struct sec_server_mech *mech;
104 static struct sec_client_mech *mechs[] = {
114 static struct sec_client_mech *mech;
118 static void *app_data;
123 if(sec_complete && data_prot) {
125 if(sec_read(fileno(F), &c, 1) <= 0)
133 block_read(int fd, void *buf, size_t len)
135 unsigned char *p = buf;
138 b = read(fd, p, len);
146 return p - (unsigned char*)buf;
150 block_write(int fd, void *buf, size_t len)
152 unsigned char *p = buf;
155 b = write(fd, p, len);
161 return p - (unsigned char*)buf;
165 sec_get_data(int fd, struct buffer *buf, int level)
170 b = block_read(fd, &len, sizeof(len));
176 buf->data = realloc(buf->data, len);
177 b = block_read(fd, buf->data, len);
182 buf->size = (*mech->decode)(app_data, buf->data, len, data_prot);
188 buffer_read(struct buffer *buf, void *data, size_t len)
190 len = min(len, buf->size - buf->index);
191 memcpy(data, (char*)buf->data + buf->index, len);
197 buffer_write(struct buffer *buf, void *data, size_t len)
199 if(buf->index + len > buf->size) {
201 if(buf->data == NULL)
204 tmp = realloc(buf->data, buf->index + len);
208 buf->size = buf->index + len;
210 memcpy((char*)buf->data + buf->index, data, len);
216 sec_read(int fd, void *data, int length)
221 if(sec_complete == 0 || data_prot == 0)
222 return read(fd, data, length);
224 if(in_buffer.eof_flag){
225 in_buffer.eof_flag = 0;
229 len = buffer_read(&in_buffer, data, length);
232 data = (char*)data + len;
235 if(sec_get_data(fd, &in_buffer, data_prot) < 0)
237 if(in_buffer.size == 0) {
239 in_buffer.eof_flag = 1;
242 len = buffer_read(&in_buffer, data, length);
245 data = (char*)data + len;
251 sec_send(int fd, char *from, int length)
255 bytes = (*mech->encode)(app_data, from, length, data_prot, &buf);
256 bytes = htonl(bytes);
257 block_write(fd, &bytes, sizeof(bytes));
258 block_write(fd, buf, ntohl(bytes));
266 if(data_prot != prot_clear) {
267 if(out_buffer.index > 0){
268 sec_write(fileno(F), out_buffer.data, out_buffer.index);
269 out_buffer.index = 0;
271 sec_send(fileno(F), NULL, 0);
278 sec_write(int fd, char *data, int length)
280 int len = buffer_size;
283 if(data_prot == prot_clear)
284 return write(fd, data, length);
286 len -= (*mech->overhead)(app_data, data_prot, len);
290 sec_send(fd, data, len);
299 sec_vfprintf2(FILE *f, const char *fmt, va_list ap)
303 if(data_prot == prot_clear)
304 return vfprintf(f, fmt, ap);
306 vasprintf(&buf, fmt, ap);
307 ret = buffer_write(&out_buffer, buf, strlen(buf));
314 sec_fprintf2(FILE *f, const char *fmt, ...)
319 ret = sec_vfprintf2(f, fmt, ap);
325 sec_putc(int c, FILE *F)
328 if(data_prot == prot_clear)
331 buffer_write(&out_buffer, &ch, 1);
332 if(c == '\n' || out_buffer.index >= 1024 /* XXX */) {
333 sec_write(fileno(F), out_buffer.data, out_buffer.index);
334 out_buffer.index = 0;
340 sec_read_msg(char *s, int level)
346 buf = malloc(strlen(s));
347 len = base64_decode(s + 4, buf); /* XXX */
349 len = (*mech->decode)(app_data, buf, len, level);
358 sscanf(buf, "%d", &code);
359 if(buf[len-1] == '\n')
367 sec_vfprintf(FILE *f, const char *fmt, va_list ap)
373 return vfprintf(f, fmt, ap);
375 vasprintf(&buf, fmt, ap);
376 len = (*mech->encode)(app_data, buf, strlen(buf), command_prot, &enc);
379 printf("Failed to encode command.\n");
382 if(base64_encode(enc, len, &buf) < 0){
383 printf("Out of memory base64-encoding.\n");
387 if(command_prot == prot_safe)
388 fprintf(f, "631 %s\r\n", buf);
389 else if(command_prot == prot_private)
390 fprintf(f, "632 %s\r\n", buf);
391 else if(command_prot == prot_confidential)
392 fprintf(f, "633 %s\r\n", buf);
394 if(command_prot == prot_safe)
395 fprintf(f, "MIC %s", buf);
396 else if(command_prot == prot_private)
397 fprintf(f, "ENC %s", buf);
398 else if(command_prot == prot_confidential)
399 fprintf(f, "CONF %s", buf);
406 sec_fprintf(FILE *f, const char *fmt, ...)
411 ret = sec_vfprintf(f, fmt, ap);
416 /* end common stuff */
421 auth(char *auth_name)
424 for(i = 0; (mech = mechs[i]) != NULL; i++){
425 if(!strcasecmp(auth_name, mech->name)){
426 app_data = realloc(app_data, mech->size);
427 if(mech->init && (*mech->init)(app_data) != 0) {
428 reply(431, "Unable to accept %s at this time", mech->name);
432 (*mech->auth)(app_data);
436 reply(334, "Send authorization data.");
438 reply(234, "Authorization complete.");
443 reply(504, "%s is unknown to me", auth_name);
447 adat(char *auth_data)
449 if(mech && !sec_complete) {
450 void *buf = malloc(strlen(auth_data));
452 len = base64_decode(auth_data, buf);
453 (*mech->adat)(app_data, buf, len);
456 reply(503, "You must %sissue an AUTH first.", mech ? "re-" : "");
463 reply(503, "Incomplete security data exchange.");
465 new = (*mech->pbsz)(app_data, size);
466 if(buffer_size != new){
470 reply(200, "PBSZ=%lu", (unsigned long)new);
480 if(buffer_size == 0){
481 reply(503, "No protection buffer size negotiated.");
485 if(!strcasecmp(pl, "C"))
487 else if(!strcasecmp(pl, "S"))
489 else if(!strcasecmp(pl, "E"))
490 p = prot_confidential;
491 else if(!strcasecmp(pl, "P"))
494 reply(504, "Unrecognized protection level.");
499 if((*mech->check_prot)(app_data, p)){
500 reply(536, "%s does not support %s protection.",
501 mech->name, level_to_name(p));
503 data_prot = (enum protection_level)p;
504 reply(200, "Data protection is %s.", level_to_name(p));
507 reply(503, "Incomplete security data exchange.");
514 if(mech->ccc && (*mech->ccc)(app_data) == 0)
515 command_prot = data_prot = prot_clear;
517 reply(534, "You must be joking.");
519 reply(503, "Incomplete security data exchange.");
522 void mec(char *msg, enum protection_level level)
527 reply(503, "Incomplete security data exchange.");
530 buf = malloc(strlen(msg) + 2); /* XXX go figure out where that 2
532 len = base64_decode(msg, buf);
533 command_prot = level;
534 if(len == (size_t)-1) {
535 reply(501, "Failed to base64-decode command");
538 len = (*mech->decode)(app_data, buf, len, level);
539 if(len == (size_t)-1) {
540 reply(535, "Failed to decode command");
543 ((char*)buf)[len] = '\0';
544 if(strstr((char*)buf, "\r\n") == NULL)
545 strcat((char*)buf, "\r\n");
546 new_ftp_command(buf);
549 /* ------------------------------------------------------------ */
552 sec_userok(char *user)
555 return (*mech->userok)(app_data, user);
562 new_ftp_command(char *command)
564 ftp_command = command;
568 delete_ftp_command(void)
577 return ftp_command != NULL;
580 enum protection_level
581 get_command_prot(void)
586 #else /* FTP_SERVER */
592 printf("Using %s for authentication.\n", mech->name);
593 printf("Using %s command channel.\n", level_to_name(command_prot));
594 printf("Using %s data channel.\n", level_to_name(data_prot));
596 printf("Protection buffer size: %lu.\n",
597 (unsigned long)buffer_size);
599 printf("Not using any security mechanism.\n");
604 sec_prot_internal(int level)
608 unsigned int s = 1048576;
610 int old_verbose = verbose;
614 printf("No security data exchange has taken place.\n");
619 ret = command("PBSZ %u", s);
621 printf("Failed to set protection buffer size.\n");
625 p = strstr(reply_string, "PBSZ=");
627 sscanf(p, "PBSZ=%u", &s);
631 verbose = old_verbose;
632 ret = command("PROT %c", level["CSEP"]); /* XXX :-) */
634 printf("Failed to set protection level.\n");
638 data_prot = (enum protection_level)level;
642 enum protection_level
643 set_command_prot(enum protection_level level)
645 enum protection_level old = command_prot;
646 command_prot = level;
651 sec_prot(int argc, char **argv)
655 if(argc < 2 || argc > 3)
658 printf("No security data exchange has taken place.\n");
662 level = name_to_level(argv[argc - 1]);
667 if((*mech->check_prot)(app_data, level)) {
668 printf("%s does not implement %s protection.\n",
669 mech->name, level_to_name(level));
674 if(argc == 2 || strncasecmp(argv[1], "data", strlen(argv[1])) == 0) {
675 if(sec_prot_internal(level) < 0){
679 } else if(strncasecmp(argv[1], "command", strlen(argv[1])) == 0)
680 set_command_prot(level);
686 printf("usage: %s [command|data] [clear|safe|confidential|private]\n",
691 static enum protection_level request_data_prot;
694 sec_set_protection_level(void)
696 if(sec_complete && data_prot != request_data_prot)
697 sec_prot_internal(request_data_prot);
702 sec_request_prot(char *level)
704 int l = name_to_level(level);
707 request_data_prot = (enum protection_level)l;
712 sec_login(char *host)
715 struct sec_client_mech **m;
716 int old_verbose = verbose;
718 verbose = -1; /* shut up all messages this will produce (they
719 are usually not very user friendly) */
721 for(m = mechs; *m && (*m)->name; m++) {
724 tmp = realloc(app_data, (*m)->size);
726 warnx ("realloc %u failed", (*m)->size);
731 if((*m)->init && (*(*m)->init)(app_data) != 0) {
732 printf("Skipping %s...\n", (*m)->name);
735 printf("Trying %s...\n", (*m)->name);
736 ret = command("AUTH %s", (*m)->name);
739 printf("%s is not supported by the server.\n", (*m)->name);
740 }else if(code == 534){
741 printf("%s rejected as security mechanism.\n", (*m)->name);
742 }else if(ret == ERROR) {
743 printf("The server doesn't support the FTP "
744 "security extensions.\n");
745 verbose = old_verbose;
751 ret = (*(*m)->auth)(app_data, host);
753 if(ret == AUTH_CONTINUE)
755 else if(ret != AUTH_OK){
756 /* mechanism is supposed to output error string */
757 verbose = old_verbose;
762 command_prot = prot_safe;
766 verbose = old_verbose;
775 (*mech->end)(app_data);
776 memset(app_data, 0, mech->size);
781 data_prot = (enum protection_level)0;
784 #endif /* FTP_SERVER */