1 /* This source code was modified by Martin Hedenfalk <mhe@stacken.kth.se> for
2 * use in Curl. His latest changes were done 2000-09-18.
4 * It has since been patched and modified a lot by Daniel Stenberg
5 * <daniel@haxx.se> to make it better applied to curl conditions, and to make
6 * it not use globals, pollute name space and more. This source code awaits a
7 * rewrite to work around the paragraph 2 in the BSD licenses as explained
10 * Copyright (c) 1998, 1999 Kungliga Tekniska Högskolan
11 * (Royal Institute of Technology, Stockholm, Sweden).
13 * Copyright (C) 2001 - 2010, Daniel Stenberg, <daniel@haxx.se>, et al.
15 * All rights reserved.
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
21 * 1. Redistributions of source code must retain the above copyright
22 * notice, this list of conditions and the following disclaimer.
24 * 2. Redistributions in binary form must reproduce the above copyright
25 * notice, this list of conditions and the following disclaimer in the
26 * documentation and/or other materials provided with the distribution.
28 * 3. Neither the name of the Institute nor the names of its contributors
29 * may be used to endorse or promote products derived from this software
30 * without specific prior written permission.
32 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
33 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46 #ifndef CURL_DISABLE_FTP
47 #if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
61 #include "curl_base64.h"
62 #include "curl_memory.h"
68 /* The last #include file should be: */
72 enum protection_level level;
75 { PROT_CLEAR, "clear" },
76 { PROT_SAFE, "safe" },
77 { PROT_CONFIDENTIAL, "confidential" },
78 { PROT_PRIVATE, "private" }
81 static enum protection_level
82 name_to_level(const char *name)
85 for(i = 0; i < (int)sizeof(level_names)/(int)sizeof(level_names[0]); i++)
86 if(checkprefix(name, level_names[i].name))
87 return level_names[i].level;
91 /* Convert a protocol |level| to its char representation.
92 We take an int to catch programming mistakes. */
93 static char level_to_char(int level) {
99 case PROT_CONFIDENTIAL:
106 /* Those 2 cases should not be reached! */
110 /* Default to the most secure alternative. */
114 static const struct Curl_sec_client_mech * const mechs[] = {
115 #if defined(HAVE_GSSAPI)
116 &Curl_krb5_client_mech,
118 #if defined(HAVE_KRB4)
119 &Curl_krb4_client_mech,
124 /* Send an FTP command defined by |message| and the optional arguments. The
125 function returns the ftp_code. If an error occurs, -1 is returned. */
126 static int ftp_send_command(struct connectdata *conn, const char *message, ...)
131 char print_buffer[50];
133 va_start(args, message);
134 vsnprintf(print_buffer, sizeof(print_buffer), message, args);
137 if(Curl_ftpsendf(conn, print_buffer) != CURLE_OK) {
141 if(Curl_GetFTPResponse(&nread, conn, &ftp_code) != CURLE_OK)
145 (void)nread; /* Unused */
149 /* Read |len| from the socket |fd| and store it in |to|. Return a CURLcode
150 saying whether an error occured or CURLE_OK if |len| was read. */
152 socket_read(curl_socket_t fd, void *to, size_t len)
159 code = Curl_read_plain(fd, to_p, len, &nread);
160 if(code == CURLE_OK) {
165 /* FIXME: We are doing a busy wait */
166 if(code == CURLE_AGAIN)
175 /* Write |len| bytes from the buffer |to| to the socket |fd|. Return a
176 CURLcode saying whether an error occured or CURLE_OK if |len| was
179 socket_write(struct connectdata *conn, curl_socket_t fd, const void *to,
182 const char *to_p = to;
187 code = Curl_write_plain(conn, fd, to_p, len, &written);
188 if(code == CURLE_OK) {
193 /* FIXME: We are doing a busy wait */
194 if(code == CURLE_AGAIN)
202 static CURLcode read_data(struct connectdata *conn,
204 struct krb4buffer *buf)
210 ret = socket_read(fd, &len, sizeof(len));
215 tmp = realloc(buf->data, len);
217 return CURLE_OUT_OF_MEMORY;
220 ret = socket_read(fd, buf->data, len);
223 buf->size = conn->mech->decode(conn->app_data, buf->data, len,
224 conn->data_prot, conn);
230 buffer_read(struct krb4buffer *buf, void *data, size_t len)
232 if(buf->size - buf->index < len)
233 len = buf->size - buf->index;
234 memcpy(data, (char*)buf->data + buf->index, len);
239 /* Matches Curl_recv signature */
240 static ssize_t sec_recv(struct connectdata *conn, int sockindex,
241 char *buffer, size_t len, CURLcode *err)
244 size_t total_read = 0;
245 curl_socket_t fd = conn->sock[sockindex];
249 /* Handle clear text response. */
250 if(conn->sec_complete == 0 || conn->data_prot == PROT_CLEAR)
251 return read(fd, buffer, len);
253 if(conn->in_buffer.eof_flag) {
254 conn->in_buffer.eof_flag = 0;
258 bytes_read = buffer_read(&conn->in_buffer, buffer, len);
260 total_read += bytes_read;
261 buffer += bytes_read;
264 if(read_data(conn, fd, &conn->in_buffer) != CURLE_OK)
266 if(conn->in_buffer.size == 0) {
268 conn->in_buffer.eof_flag = 1;
271 bytes_read = buffer_read(&conn->in_buffer, buffer, len);
273 total_read += bytes_read;
274 buffer += bytes_read;
276 /* FIXME: Check for overflow */
280 /* Send |length| bytes from |from| to the |fd| socket taking care of encoding
281 and negociating with the server. |from| can be NULL. */
282 /* FIXME: We don't check for errors nor report any! */
283 static void do_sec_send(struct connectdata *conn, curl_socket_t fd,
284 const char *from, int length)
290 enum protection_level prot_level = conn->data_prot;
291 bool iscmd = prot_level == PROT_CMD;
293 DEBUGASSERT(prot_level > PROT_NONE && prot_level < PROT_LAST);
296 if(!strncmp(from, "PASS ", 5) || !strncmp(from, "ACCT ", 5))
297 prot_level = PROT_PRIVATE;
299 prot_level = conn->command_prot;
301 bytes = conn->mech->encode(conn->app_data, from, length, prot_level,
302 (void**)&buffer, conn);
304 bytes = Curl_base64_encode(conn->data, buffer, bytes, &cmd_buffer);
306 static const char *enc = "ENC ";
307 static const char *mic = "MIC ";
308 if(prot_level == PROT_PRIVATE)
309 socket_write(conn, fd, enc, 4);
311 socket_write(conn, fd, mic, 4);
313 socket_write(conn, fd, cmd_buffer, bytes);
314 socket_write(conn, fd, "\r\n", 2);
315 infof(conn->data, "Send: %s%s\n", prot_level == PROT_PRIVATE?enc:mic,
321 htonl_bytes = htonl(bytes);
322 socket_write(conn, fd, &htonl_bytes, sizeof(htonl_bytes));
323 socket_write(conn, fd, buffer, bytes);
328 static ssize_t sec_write(struct connectdata *conn, curl_socket_t fd,
329 const char *buffer, size_t length)
331 /* FIXME: Check for overflow */
332 ssize_t len = conn->buffer_size;
335 len -= conn->mech->overhead(conn->app_data, conn->data_prot, len);
339 if(len >= 0 || length < (size_t)len) {
340 /* FIXME: Check for overflow. */
343 do_sec_send(conn, fd, buffer, len);
351 /* Matches Curl_send signature */
352 static ssize_t sec_send(struct connectdata *conn, int sockindex,
353 const void *buffer, size_t len, CURLcode *err)
355 curl_socket_t fd = conn->sock[sockindex];
357 return sec_write(conn, fd, buffer, len);
360 int Curl_sec_read_msg(struct connectdata *conn, char *buffer,
361 enum protection_level level)
363 /* decoded_len should be size_t or ssize_t but conn->mech->decode returns an
369 DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
371 decoded_len = Curl_base64_decode(buffer + 4, (unsigned char **)&buf);
372 if(decoded_len <= 0) {
377 decoded_len = conn->mech->decode(conn->app_data, buf, decoded_len,
379 if(decoded_len <= 0) {
384 if(conn->data->set.verbose) {
385 buf[decoded_len] = '\n';
386 Curl_debug(conn->data, CURLINFO_HEADER_IN, buf, decoded_len + 1, conn);
389 buf[decoded_len] = '\0';
390 DEBUGASSERT(decoded_len > 3);
394 /* Check for error? */
395 sscanf(buf, "%d", &ret_code);
398 if(buf[decoded_len - 1] == '\n')
399 buf[decoded_len - 1] = '\0';
400 /* FIXME: Is |buffer| length always greater than |decoded_len|? */
406 /* FIXME: The error code returned here is never checked. */
407 static int sec_set_protection_level(struct connectdata *conn)
411 static unsigned int buffer_size = 1 << 20; /* 1048576 */
412 enum protection_level level = conn->request_data_prot;
414 DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
416 if(!conn->sec_complete) {
417 infof(conn->data, "Trying to change the protection level after the"
418 "completion of the data exchange.\n");
422 /* Bail out if we try to set up the same level */
423 if(conn->data_prot == level)
427 code = ftp_send_command(conn, "PBSZ %u", buffer_size);
432 failf(conn->data, "Failed to set the protection's buffer size.");
435 conn->buffer_size = buffer_size;
437 pbsz = strstr(conn->data->state.buffer, "PBSZ=");
439 /* FIXME: Checks for errors in sscanf? */
440 sscanf(pbsz, "PBSZ=%u", &buffer_size);
441 if(buffer_size < conn->buffer_size)
442 conn->buffer_size = buffer_size;
446 /* Now try to negiociate the protection level. */
447 code = ftp_send_command(conn, "PROT %c", level_to_char(level));
453 failf(conn->data, "Failed to set the protection level.");
457 conn->data_prot = level;
458 if(level == PROT_PRIVATE)
459 conn->command_prot = level;
465 Curl_sec_request_prot(struct connectdata *conn, const char *level)
467 enum protection_level l = name_to_level(level);
470 DEBUGASSERT(l > PROT_NONE && l < PROT_LAST);
471 conn->request_data_prot = l;
475 static CURLcode choose_mech(struct connectdata *conn)
478 struct SessionHandle *data = conn->data;
479 const struct Curl_sec_client_mech * const *mech;
480 void *tmp_allocation;
481 const char *mech_name;
483 for(mech = mechs; (*mech); ++mech) {
484 mech_name = (*mech)->name;
485 /* We have no mechanism with a NULL name but keep this check */
486 DEBUGASSERT(mech_name != NULL);
487 if(mech_name == NULL) {
488 infof(data, "Skipping mechanism with empty name (%p)\n", mech);
491 tmp_allocation = realloc(conn->app_data, (*mech)->size);
492 if(tmp_allocation == NULL) {
493 failf(data, "Failed realloc of size %u", (*mech)->size);
495 return CURLE_OUT_OF_MEMORY;
497 conn->app_data = tmp_allocation;
500 ret = (*mech)->init(conn->app_data);
502 infof(data, "Failed initialization for %s. Skipping it.\n", mech_name);
507 infof(data, "Trying mechanism %s...\n", mech_name);
508 ret = ftp_send_command(conn, "AUTH %s", mech_name);
510 /* FIXME: This error is too generic but it is OK for now. */
511 return CURLE_COULDNT_CONNECT;
516 infof(data, "Mechanism %s is not supported by the server (server "
517 "returned ftp code: 504).\n", mech_name);
520 infof(data, "Mechanism %s was rejected by the server (server returned "
521 "ftp code: 534).\n", mech_name);
525 infof(data, "The server does not support the security extensions.\n");
526 return CURLE_USE_SSL_FAILED;
534 ret = (*mech)->auth(conn->app_data, conn);
536 if(ret == AUTH_CONTINUE)
538 else if(ret != AUTH_OK) {
539 /* Mechanism has dumped the error to stderr, don't error here. */
542 DEBUGASSERT(ret == AUTH_OK);
545 conn->sec_complete = 1;
546 conn->recv[FIRSTSOCKET] = sec_recv;
547 conn->send[FIRSTSOCKET] = sec_send;
548 conn->recv[SECONDARYSOCKET] = sec_recv;
549 conn->send[SECONDARYSOCKET] = sec_send;
550 conn->command_prot = PROT_SAFE;
551 /* Set the requested protection level */
553 (void)sec_set_protection_level(conn);
557 return mech != NULL ? CURLE_OK : CURLE_FAILED_INIT;
561 Curl_sec_login(struct connectdata *conn)
563 return choose_mech(conn);
568 Curl_sec_end(struct connectdata *conn)
570 if(conn->mech != NULL && conn->mech->end)
571 conn->mech->end(conn->app_data);
573 free(conn->app_data);
574 conn->app_data = NULL;
576 if(conn->in_buffer.data) {
577 free(conn->in_buffer.data);
578 conn->in_buffer.data = NULL;
579 conn->in_buffer.size = 0;
580 conn->in_buffer.index = 0;
581 /* FIXME: Is this really needed? */
582 conn->in_buffer.eof_flag = 0;
584 conn->sec_complete = 0;
585 conn->data_prot = PROT_CLEAR;
589 #endif /* HAVE_KRB4 || HAVE_GSSAPI */
591 #endif /* CURL_DISABLE_FTP */