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, 2013 Kungliga Tekniska Högskolan
11 * (Royal Institute of Technology, Stockholm, Sweden).
13 * Copyright (C) 2001 - 2014, 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
44 #include "curl_setup.h"
46 #ifndef CURL_DISABLE_FTP
58 #include "curl_base64.h"
59 #include "curl_memory.h"
66 /* The last #include file should be: */
70 enum protection_level level;
73 { PROT_CLEAR, "clear" },
74 { PROT_SAFE, "safe" },
75 { PROT_CONFIDENTIAL, "confidential" },
76 { PROT_PRIVATE, "private" }
79 static enum protection_level
80 name_to_level(const char *name)
83 for(i = 0; i < (int)sizeof(level_names)/(int)sizeof(level_names[0]); i++)
84 if(checkprefix(name, level_names[i].name))
85 return level_names[i].level;
89 /* Convert a protocol |level| to its char representation.
90 We take an int to catch programming mistakes. */
91 static char level_to_char(int level) {
97 case PROT_CONFIDENTIAL:
104 /* Those 2 cases should not be reached! */
108 /* Default to the most secure alternative. */
112 static const struct Curl_sec_client_mech * const mechs[] = {
114 &Curl_krb5_client_mech,
119 /* Send an FTP command defined by |message| and the optional arguments. The
120 function returns the ftp_code. If an error occurs, -1 is returned. */
121 static int ftp_send_command(struct connectdata *conn, const char *message, ...)
126 char print_buffer[50];
128 va_start(args, message);
129 vsnprintf(print_buffer, sizeof(print_buffer), message, args);
132 if(Curl_ftpsendf(conn, print_buffer)) {
136 if(Curl_GetFTPResponse(&nread, conn, &ftp_code))
140 (void)nread; /* Unused */
144 /* Read |len| from the socket |fd| and store it in |to|. Return a CURLcode
145 saying whether an error occurred or CURLE_OK if |len| was read. */
147 socket_read(curl_socket_t fd, void *to, size_t len)
154 result = Curl_read_plain(fd, to_p, len, &nread);
160 /* FIXME: We are doing a busy wait */
161 if(result == CURLE_AGAIN)
170 /* Write |len| bytes from the buffer |to| to the socket |fd|. Return a
171 CURLcode saying whether an error occurred or CURLE_OK if |len| was
174 socket_write(struct connectdata *conn, curl_socket_t fd, const void *to,
177 const char *to_p = to;
182 result = Curl_write_plain(conn, fd, to_p, len, &written);
188 /* FIXME: We are doing a busy wait */
189 if(result == CURLE_AGAIN)
197 static CURLcode read_data(struct connectdata *conn,
199 struct krb5buffer *buf)
205 result = socket_read(fd, &len, sizeof(len));
210 tmp = realloc(buf->data, len);
212 return CURLE_OUT_OF_MEMORY;
215 result = socket_read(fd, buf->data, len);
218 buf->size = conn->mech->decode(conn->app_data, buf->data, len,
219 conn->data_prot, conn);
225 buffer_read(struct krb5buffer *buf, void *data, size_t len)
227 if(buf->size - buf->index < len)
228 len = buf->size - buf->index;
229 memcpy(data, (char*)buf->data + buf->index, len);
234 /* Matches Curl_recv signature */
235 static ssize_t sec_recv(struct connectdata *conn, int sockindex,
236 char *buffer, size_t len, CURLcode *err)
239 size_t total_read = 0;
240 curl_socket_t fd = conn->sock[sockindex];
244 /* Handle clear text response. */
245 if(conn->sec_complete == 0 || conn->data_prot == PROT_CLEAR)
246 return read(fd, buffer, len);
248 if(conn->in_buffer.eof_flag) {
249 conn->in_buffer.eof_flag = 0;
253 bytes_read = buffer_read(&conn->in_buffer, buffer, len);
255 total_read += bytes_read;
256 buffer += bytes_read;
259 if(read_data(conn, fd, &conn->in_buffer))
261 if(conn->in_buffer.size == 0) {
263 conn->in_buffer.eof_flag = 1;
266 bytes_read = buffer_read(&conn->in_buffer, buffer, len);
268 total_read += bytes_read;
269 buffer += bytes_read;
271 /* FIXME: Check for overflow */
275 /* Send |length| bytes from |from| to the |fd| socket taking care of encoding
276 and negociating with the server. |from| can be NULL. */
277 /* FIXME: We don't check for errors nor report any! */
278 static void do_sec_send(struct connectdata *conn, curl_socket_t fd,
279 const char *from, int length)
281 int bytes, htonl_bytes; /* 32-bit integers for htonl */
286 enum protection_level prot_level = conn->data_prot;
287 bool iscmd = (prot_level == PROT_CMD)?TRUE:FALSE;
289 DEBUGASSERT(prot_level > PROT_NONE && prot_level < PROT_LAST);
292 if(!strncmp(from, "PASS ", 5) || !strncmp(from, "ACCT ", 5))
293 prot_level = PROT_PRIVATE;
295 prot_level = conn->command_prot;
297 bytes = conn->mech->encode(conn->app_data, from, length, prot_level,
299 if(!buffer || bytes <= 0)
303 error = Curl_base64_encode(conn->data, buffer, curlx_sitouz(bytes),
304 &cmd_buffer, &cmd_size);
310 static const char *enc = "ENC ";
311 static const char *mic = "MIC ";
312 if(prot_level == PROT_PRIVATE)
313 socket_write(conn, fd, enc, 4);
315 socket_write(conn, fd, mic, 4);
317 socket_write(conn, fd, cmd_buffer, cmd_size);
318 socket_write(conn, fd, "\r\n", 2);
319 infof(conn->data, "Send: %s%s\n", prot_level == PROT_PRIVATE?enc:mic,
325 htonl_bytes = htonl(bytes);
326 socket_write(conn, fd, &htonl_bytes, sizeof(htonl_bytes));
327 socket_write(conn, fd, buffer, curlx_sitouz(bytes));
332 static ssize_t sec_write(struct connectdata *conn, curl_socket_t fd,
333 const char *buffer, size_t length)
335 ssize_t tx = 0, len = conn->buffer_size;
337 len -= conn->mech->overhead(conn->app_data, conn->data_prot,
342 if(length < (size_t)len)
345 do_sec_send(conn, fd, buffer, curlx_sztosi(len));
353 /* Matches Curl_send signature */
354 static ssize_t sec_send(struct connectdata *conn, int sockindex,
355 const void *buffer, size_t len, CURLcode *err)
357 curl_socket_t fd = conn->sock[sockindex];
359 return sec_write(conn, fd, buffer, len);
362 int Curl_sec_read_msg(struct connectdata *conn, char *buffer,
363 enum protection_level level)
365 /* decoded_len should be size_t or ssize_t but conn->mech->decode returns an
370 size_t decoded_sz = 0;
373 DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
375 error = Curl_base64_decode(buffer + 4, (unsigned char **)&buf, &decoded_sz);
376 if(error || decoded_sz == 0)
379 if(decoded_sz > (size_t)INT_MAX) {
383 decoded_len = curlx_uztosi(decoded_sz);
385 decoded_len = conn->mech->decode(conn->app_data, buf, decoded_len,
387 if(decoded_len <= 0) {
392 if(conn->data->set.verbose) {
393 buf[decoded_len] = '\n';
394 Curl_debug(conn->data, CURLINFO_HEADER_IN, buf, decoded_len + 1, conn);
397 buf[decoded_len] = '\0';
398 DEBUGASSERT(decoded_len > 3);
402 /* Check for error? */
403 (void)sscanf(buf, "%d", &ret_code);
406 if(buf[decoded_len - 1] == '\n')
407 buf[decoded_len - 1] = '\0';
408 /* FIXME: Is |buffer| length always greater than |decoded_len|? */
414 /* FIXME: The error code returned here is never checked. */
415 static int sec_set_protection_level(struct connectdata *conn)
419 static unsigned int buffer_size = 1 << 20; /* 1048576 */
420 enum protection_level level = conn->request_data_prot;
422 DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
424 if(!conn->sec_complete) {
425 infof(conn->data, "Trying to change the protection level after the"
426 "completion of the data exchange.\n");
430 /* Bail out if we try to set up the same level */
431 if(conn->data_prot == level)
435 code = ftp_send_command(conn, "PBSZ %u", buffer_size);
440 failf(conn->data, "Failed to set the protection's buffer size.");
443 conn->buffer_size = buffer_size;
445 pbsz = strstr(conn->data->state.buffer, "PBSZ=");
447 /* FIXME: Checks for errors in sscanf? */
448 sscanf(pbsz, "PBSZ=%u", &buffer_size);
449 if(buffer_size < conn->buffer_size)
450 conn->buffer_size = buffer_size;
454 /* Now try to negiociate the protection level. */
455 code = ftp_send_command(conn, "PROT %c", level_to_char(level));
461 failf(conn->data, "Failed to set the protection level.");
465 conn->data_prot = level;
466 if(level == PROT_PRIVATE)
467 conn->command_prot = level;
473 Curl_sec_request_prot(struct connectdata *conn, const char *level)
475 enum protection_level l = name_to_level(level);
478 DEBUGASSERT(l > PROT_NONE && l < PROT_LAST);
479 conn->request_data_prot = l;
483 static CURLcode choose_mech(struct connectdata *conn)
486 struct SessionHandle *data = conn->data;
487 const struct Curl_sec_client_mech * const *mech;
488 void *tmp_allocation;
489 const char *mech_name;
491 for(mech = mechs; (*mech); ++mech) {
492 mech_name = (*mech)->name;
493 /* We have no mechanism with a NULL name but keep this check */
494 DEBUGASSERT(mech_name != NULL);
495 if(mech_name == NULL) {
496 infof(data, "Skipping mechanism with empty name (%p)\n", (void *)mech);
499 tmp_allocation = realloc(conn->app_data, (*mech)->size);
500 if(tmp_allocation == NULL) {
501 failf(data, "Failed realloc of size %u", (*mech)->size);
503 return CURLE_OUT_OF_MEMORY;
505 conn->app_data = tmp_allocation;
508 ret = (*mech)->init(conn->app_data);
510 infof(data, "Failed initialization for %s. Skipping it.\n", mech_name);
515 infof(data, "Trying mechanism %s...\n", mech_name);
516 ret = ftp_send_command(conn, "AUTH %s", mech_name);
518 /* FIXME: This error is too generic but it is OK for now. */
519 return CURLE_COULDNT_CONNECT;
524 infof(data, "Mechanism %s is not supported by the server (server "
525 "returned ftp code: 504).\n", mech_name);
528 infof(data, "Mechanism %s was rejected by the server (server returned "
529 "ftp code: 534).\n", mech_name);
533 infof(data, "server does not support the security extensions\n");
534 return CURLE_USE_SSL_FAILED;
542 ret = (*mech)->auth(conn->app_data, conn);
544 if(ret == AUTH_CONTINUE)
546 else if(ret != AUTH_OK) {
547 /* Mechanism has dumped the error to stderr, don't error here. */
550 DEBUGASSERT(ret == AUTH_OK);
553 conn->sec_complete = 1;
554 conn->recv[FIRSTSOCKET] = sec_recv;
555 conn->send[FIRSTSOCKET] = sec_send;
556 conn->recv[SECONDARYSOCKET] = sec_recv;
557 conn->send[SECONDARYSOCKET] = sec_send;
558 conn->command_prot = PROT_SAFE;
559 /* Set the requested protection level */
561 (void)sec_set_protection_level(conn);
565 return *mech != NULL ? CURLE_OK : CURLE_FAILED_INIT;
569 Curl_sec_login(struct connectdata *conn)
571 return choose_mech(conn);
576 Curl_sec_end(struct connectdata *conn)
578 if(conn->mech != NULL && conn->mech->end)
579 conn->mech->end(conn->app_data);
581 free(conn->app_data);
582 conn->app_data = NULL;
584 if(conn->in_buffer.data) {
585 free(conn->in_buffer.data);
586 conn->in_buffer.data = NULL;
587 conn->in_buffer.size = 0;
588 conn->in_buffer.index = 0;
589 /* FIXME: Is this really needed? */
590 conn->in_buffer.eof_flag = 0;
592 conn->sec_complete = 0;
593 conn->data_prot = PROT_CLEAR;
597 #endif /* HAVE_GSSAPI */
599 #endif /* CURL_DISABLE_FTP */