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 - 2015, 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 /* Send an FTP command defined by |message| and the optional arguments. The
113 function returns the ftp_code. If an error occurs, -1 is returned. */
114 static int ftp_send_command(struct connectdata *conn, const char *message, ...)
119 char print_buffer[50];
121 va_start(args, message);
122 vsnprintf(print_buffer, sizeof(print_buffer), message, args);
125 if(Curl_ftpsendf(conn, print_buffer)) {
129 if(Curl_GetFTPResponse(&nread, conn, &ftp_code))
133 (void)nread; /* Unused */
137 /* Read |len| from the socket |fd| and store it in |to|. Return a CURLcode
138 saying whether an error occurred or CURLE_OK if |len| was read. */
140 socket_read(curl_socket_t fd, void *to, size_t len)
147 result = Curl_read_plain(fd, to_p, len, &nread);
153 /* FIXME: We are doing a busy wait */
154 if(result == CURLE_AGAIN)
163 /* Write |len| bytes from the buffer |to| to the socket |fd|. Return a
164 CURLcode saying whether an error occurred or CURLE_OK if |len| was
167 socket_write(struct connectdata *conn, curl_socket_t fd, const void *to,
170 const char *to_p = to;
175 result = Curl_write_plain(conn, fd, to_p, len, &written);
181 /* FIXME: We are doing a busy wait */
182 if(result == CURLE_AGAIN)
190 static CURLcode read_data(struct connectdata *conn,
192 struct krb5buffer *buf)
198 result = socket_read(fd, &len, sizeof(len));
203 tmp = realloc(buf->data, len);
205 return CURLE_OUT_OF_MEMORY;
208 result = socket_read(fd, buf->data, len);
211 buf->size = conn->mech->decode(conn->app_data, buf->data, len,
212 conn->data_prot, conn);
218 buffer_read(struct krb5buffer *buf, void *data, size_t len)
220 if(buf->size - buf->index < len)
221 len = buf->size - buf->index;
222 memcpy(data, (char*)buf->data + buf->index, len);
227 /* Matches Curl_recv signature */
228 static ssize_t sec_recv(struct connectdata *conn, int sockindex,
229 char *buffer, size_t len, CURLcode *err)
232 size_t total_read = 0;
233 curl_socket_t fd = conn->sock[sockindex];
237 /* Handle clear text response. */
238 if(conn->sec_complete == 0 || conn->data_prot == PROT_CLEAR)
239 return read(fd, buffer, len);
241 if(conn->in_buffer.eof_flag) {
242 conn->in_buffer.eof_flag = 0;
246 bytes_read = buffer_read(&conn->in_buffer, buffer, len);
248 total_read += bytes_read;
249 buffer += bytes_read;
252 if(read_data(conn, fd, &conn->in_buffer))
254 if(conn->in_buffer.size == 0) {
256 conn->in_buffer.eof_flag = 1;
259 bytes_read = buffer_read(&conn->in_buffer, buffer, len);
261 total_read += bytes_read;
262 buffer += bytes_read;
264 /* FIXME: Check for overflow */
268 /* Send |length| bytes from |from| to the |fd| socket taking care of encoding
269 and negociating with the server. |from| can be NULL. */
270 /* FIXME: We don't check for errors nor report any! */
271 static void do_sec_send(struct connectdata *conn, curl_socket_t fd,
272 const char *from, int length)
274 int bytes, htonl_bytes; /* 32-bit integers for htonl */
279 enum protection_level prot_level = conn->data_prot;
280 bool iscmd = (prot_level == PROT_CMD)?TRUE:FALSE;
282 DEBUGASSERT(prot_level > PROT_NONE && prot_level < PROT_LAST);
285 if(!strncmp(from, "PASS ", 5) || !strncmp(from, "ACCT ", 5))
286 prot_level = PROT_PRIVATE;
288 prot_level = conn->command_prot;
290 bytes = conn->mech->encode(conn->app_data, from, length, prot_level,
292 if(!buffer || bytes <= 0)
296 error = Curl_base64_encode(conn->data, buffer, curlx_sitouz(bytes),
297 &cmd_buffer, &cmd_size);
303 static const char *enc = "ENC ";
304 static const char *mic = "MIC ";
305 if(prot_level == PROT_PRIVATE)
306 socket_write(conn, fd, enc, 4);
308 socket_write(conn, fd, mic, 4);
310 socket_write(conn, fd, cmd_buffer, cmd_size);
311 socket_write(conn, fd, "\r\n", 2);
312 infof(conn->data, "Send: %s%s\n", prot_level == PROT_PRIVATE?enc:mic,
318 htonl_bytes = htonl(bytes);
319 socket_write(conn, fd, &htonl_bytes, sizeof(htonl_bytes));
320 socket_write(conn, fd, buffer, curlx_sitouz(bytes));
325 static ssize_t sec_write(struct connectdata *conn, curl_socket_t fd,
326 const char *buffer, size_t length)
328 ssize_t tx = 0, len = conn->buffer_size;
330 len -= conn->mech->overhead(conn->app_data, conn->data_prot,
335 if(length < (size_t)len)
338 do_sec_send(conn, fd, buffer, curlx_sztosi(len));
346 /* Matches Curl_send signature */
347 static ssize_t sec_send(struct connectdata *conn, int sockindex,
348 const void *buffer, size_t len, CURLcode *err)
350 curl_socket_t fd = conn->sock[sockindex];
352 return sec_write(conn, fd, buffer, len);
355 int Curl_sec_read_msg(struct connectdata *conn, char *buffer,
356 enum protection_level level)
358 /* decoded_len should be size_t or ssize_t but conn->mech->decode returns an
363 size_t decoded_sz = 0;
366 DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
368 error = Curl_base64_decode(buffer + 4, (unsigned char **)&buf, &decoded_sz);
369 if(error || decoded_sz == 0)
372 if(decoded_sz > (size_t)INT_MAX) {
376 decoded_len = curlx_uztosi(decoded_sz);
378 decoded_len = conn->mech->decode(conn->app_data, buf, decoded_len,
380 if(decoded_len <= 0) {
385 if(conn->data->set.verbose) {
386 buf[decoded_len] = '\n';
387 Curl_debug(conn->data, CURLINFO_HEADER_IN, buf, decoded_len + 1, conn);
390 buf[decoded_len] = '\0';
392 /* suspiciously short */
396 /* safe to ignore return code */
397 (void)sscanf(buf, "%d", &ret_code);
399 if(buf[decoded_len - 1] == '\n')
400 buf[decoded_len - 1] = '\0';
401 /* FIXME: Is |buffer| length always greater than |decoded_len|? */
407 /* FIXME: The error code returned here is never checked. */
408 static int sec_set_protection_level(struct connectdata *conn)
412 static unsigned int buffer_size = 1 << 20; /* 1048576 */
413 enum protection_level level = conn->request_data_prot;
415 DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
417 if(!conn->sec_complete) {
418 infof(conn->data, "Trying to change the protection level after the"
419 "completion of the data exchange.\n");
423 /* Bail out if we try to set up the same level */
424 if(conn->data_prot == level)
428 code = ftp_send_command(conn, "PBSZ %u", buffer_size);
433 failf(conn->data, "Failed to set the protection's buffer size.");
436 conn->buffer_size = buffer_size;
438 pbsz = strstr(conn->data->state.buffer, "PBSZ=");
440 /* ignore return code, use default value if it fails */
441 (void)sscanf(pbsz, "PBSZ=%u", &buffer_size);
442 if(buffer_size < conn->buffer_size)
443 conn->buffer_size = buffer_size;
447 /* Now try to negiociate the protection level. */
448 code = ftp_send_command(conn, "PROT %c", level_to_char(level));
454 failf(conn->data, "Failed to set the protection level.");
458 conn->data_prot = level;
459 if(level == PROT_PRIVATE)
460 conn->command_prot = level;
466 Curl_sec_request_prot(struct connectdata *conn, const char *level)
468 enum protection_level l = name_to_level(level);
471 DEBUGASSERT(l > PROT_NONE && l < PROT_LAST);
472 conn->request_data_prot = l;
476 static CURLcode choose_mech(struct connectdata *conn)
479 struct SessionHandle *data = conn->data;
480 void *tmp_allocation;
481 const struct Curl_sec_client_mech *mech = &Curl_krb5_client_mech;
483 tmp_allocation = realloc(conn->app_data, mech->size);
484 if(tmp_allocation == NULL) {
485 failf(data, "Failed realloc of size %u", mech->size);
487 return CURLE_OUT_OF_MEMORY;
489 conn->app_data = tmp_allocation;
492 ret = mech->init(conn->app_data);
494 infof(data, "Failed initialization for %s. Skipping it.\n",
496 return CURLE_FAILED_INIT;
500 infof(data, "Trying mechanism %s...\n", mech->name);
501 ret = ftp_send_command(conn, "AUTH %s", mech->name);
503 /* FIXME: This error is too generic but it is OK for now. */
504 return CURLE_COULDNT_CONNECT;
509 infof(data, "Mechanism %s is not supported by the server (server "
510 "returned ftp code: 504).\n", mech->name);
513 infof(data, "Mechanism %s was rejected by the server (server returned "
514 "ftp code: 534).\n", mech->name);
518 infof(data, "server does not support the security extensions\n");
519 return CURLE_USE_SSL_FAILED;
523 return CURLE_LOGIN_DENIED;
527 ret = mech->auth(conn->app_data, conn);
529 if(ret != AUTH_CONTINUE) {
531 /* Mechanism has dumped the error to stderr, don't error here. */
534 DEBUGASSERT(ret == AUTH_OK);
537 conn->sec_complete = 1;
538 conn->recv[FIRSTSOCKET] = sec_recv;
539 conn->send[FIRSTSOCKET] = sec_send;
540 conn->recv[SECONDARYSOCKET] = sec_recv;
541 conn->send[SECONDARYSOCKET] = sec_send;
542 conn->command_prot = PROT_SAFE;
543 /* Set the requested protection level */
545 (void)sec_set_protection_level(conn);
552 Curl_sec_login(struct connectdata *conn)
554 return choose_mech(conn);
559 Curl_sec_end(struct connectdata *conn)
561 if(conn->mech != NULL && conn->mech->end)
562 conn->mech->end(conn->app_data);
563 free(conn->app_data);
564 conn->app_data = NULL;
565 if(conn->in_buffer.data) {
566 free(conn->in_buffer.data);
567 conn->in_buffer.data = NULL;
568 conn->in_buffer.size = 0;
569 conn->in_buffer.index = 0;
570 /* FIXME: Is this really needed? */
571 conn->in_buffer.eof_flag = 0;
573 conn->sec_complete = 0;
574 conn->data_prot = PROT_CLEAR;
578 #endif /* HAVE_GSSAPI */
580 #endif /* CURL_DISABLE_FTP */