1 /* GSSAPI/krb5 support for FTP - loosely based on old krb4.c
3 * Copyright (c) 1995, 1996, 1997, 1998, 1999, 2013 Kungliga Tekniska Högskolan
4 * (Royal Institute of Technology, Stockholm, Sweden).
5 * Copyright (c) 2004 - 2012 Daniel Stenberg
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the Institute nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 #include "curl_setup.h"
37 #ifndef CURL_DISABLE_FTP
40 #ifdef HAVE_OLD_GSSMIT
41 #define GSS_C_NT_HOSTBASED_SERVICE gss_nt_service_name
50 #include "curl_base64.h"
52 #include "curl_gssapi.h"
55 #include "curl_memory.h"
58 #define _MPRINTF_REPLACE /* use our functions only */
59 #include <curl/mprintf.h>
61 /* The last #include file should be: */
64 #define LOCAL_ADDR (&conn->local_addr)
65 #define REMOTE_ADDR conn->ip_addr->ai_addr
68 krb5_init(void *app_data)
70 gss_ctx_id_t *context = app_data;
71 /* Make sure our context is initialized for krb5_end. */
72 *context = GSS_C_NO_CONTEXT;
77 krb5_check_prot(void *app_data, int level)
79 (void)app_data; /* unused */
80 if(level == PROT_CONFIDENTIAL)
86 krb5_decode(void *app_data, void *buf, int len,
87 int level UNUSED_PARAM,
88 struct connectdata *conn UNUSED_PARAM)
90 gss_ctx_id_t *context = app_data;
92 gss_buffer_desc enc, dec;
99 maj = gss_unseal(&min, *context, &enc, &dec, NULL, NULL);
100 if(maj != GSS_S_COMPLETE) {
106 memcpy(buf, dec.value, dec.length);
107 len = curlx_uztosi(dec.length);
108 gss_release_buffer(&min, &dec);
114 krb5_overhead(void *app_data, int level, int len)
116 /* no arguments are used */
124 krb5_encode(void *app_data, const void *from, int length, int level, void **to,
125 struct connectdata *conn UNUSED_PARAM)
127 gss_ctx_id_t *context = app_data;
128 gss_buffer_desc dec, enc;
136 /* NOTE that the cast is safe, neither of the krb5, gnu gss and heimdal
137 * libraries modify the input buffer in gss_seal()
139 dec.value = (void*)from;
141 maj = gss_seal(&min, *context,
142 level == PROT_PRIVATE,
146 if(maj != GSS_S_COMPLETE)
149 /* malloc a new buffer, in case gss_release_buffer doesn't work as
151 *to = malloc(enc.length);
154 memcpy(*to, enc.value, enc.length);
155 len = curlx_uztosi(enc.length);
156 gss_release_buffer(&min, &enc);
161 krb5_auth(void *app_data, struct connectdata *conn)
165 const char *host = conn->host.name;
167 curl_socklen_t l = sizeof(conn->local_addr);
168 struct SessionHandle *data = conn->data;
170 const char *service = "ftp", *srv_host = "host";
171 gss_buffer_desc input_buffer, output_buffer, _gssresp, *gssresp;
174 gss_ctx_id_t *context = app_data;
175 struct gss_channel_bindings_struct chan;
176 size_t base64_sz = 0;
178 if(getsockname(conn->sock[FIRSTSOCKET],
179 (struct sockaddr *)LOCAL_ADDR, &l) < 0)
180 perror("getsockname()");
182 chan.initiator_addrtype = GSS_C_AF_INET;
183 chan.initiator_address.length = l - 4;
184 chan.initiator_address.value =
185 &((struct sockaddr_in *)LOCAL_ADDR)->sin_addr.s_addr;
186 chan.acceptor_addrtype = GSS_C_AF_INET;
187 chan.acceptor_address.length = l - 4;
188 chan.acceptor_address.value =
189 &((struct sockaddr_in *)REMOTE_ADDR)->sin_addr.s_addr;
190 chan.application_data.length = 0;
191 chan.application_data.value = NULL;
193 /* this loop will execute twice (once for service, once for host) */
195 /* this really shouldn't be repeated here, but can't help it */
196 if(service == srv_host) {
197 result = Curl_ftpsendf(conn, "AUTH GSSAPI");
201 if(Curl_GetFTPResponse(&nread, conn, NULL))
204 if(data->state.buffer[0] != '3')
208 input_buffer.value = data->state.buffer;
209 input_buffer.length = snprintf(input_buffer.value, BUFSIZE, "%s@%s",
211 maj = gss_import_name(&min, &input_buffer, GSS_C_NT_HOSTBASED_SERVICE,
213 if(maj != GSS_S_COMPLETE) {
214 gss_release_name(&min, &gssname);
215 if(service == srv_host) {
216 Curl_failf(data, "Error importing service name %s",
223 /* We pass NULL as |output_name_type| to avoid a leak. */
224 gss_display_name(&min, gssname, &output_buffer, NULL);
225 Curl_infof(data, "Trying against %s\n", output_buffer.value);
226 gssresp = GSS_C_NO_BUFFER;
227 *context = GSS_C_NO_CONTEXT;
230 /* Release the buffer at each iteration to avoid leaking: the first time
231 we are releasing the memory from gss_display_name. The last item is
232 taken care by a final gss_release_buffer. */
233 gss_release_buffer(&min, &output_buffer);
235 maj = Curl_gss_init_sec_context(data,
245 free(_gssresp.value);
250 Curl_infof(data, "Error creating security context\n");
255 if(output_buffer.length != 0) {
256 result = Curl_base64_encode(data, (char *)output_buffer.value,
257 output_buffer.length, &p, &base64_sz);
259 Curl_infof(data,"base64-encoding: %s\n", curl_easy_strerror(result));
264 result = Curl_ftpsendf(conn, "ADAT %s", p);
273 if(Curl_GetFTPResponse(&nread, conn, NULL)) {
278 if(data->state.buffer[0] != '2' && data->state.buffer[0] != '3') {
279 Curl_infof(data, "Server didn't accept auth data\n");
284 p = data->state.buffer + 4;
285 p = strstr(p, "ADAT=");
287 result = Curl_base64_decode(p + 5,
288 (unsigned char **)&_gssresp.value,
291 Curl_failf(data,"base64-decoding: %s", curl_easy_strerror(result));
299 } while(maj == GSS_S_CONTINUE_NEEDED);
301 gss_release_name(&min, &gssname);
302 gss_release_buffer(&min, &output_buffer);
305 free(_gssresp.value);
307 if(ret == AUTH_OK || service == srv_host)
315 static void krb5_end(void *app_data)
318 gss_ctx_id_t *context = app_data;
319 if(*context != GSS_C_NO_CONTEXT) {
323 gss_delete_sec_context(&min, context, GSS_C_NO_BUFFER);
324 DEBUGASSERT(maj == GSS_S_COMPLETE);
328 struct Curl_sec_client_mech Curl_krb5_client_mech = {
330 sizeof(gss_ctx_id_t),
340 #endif /* HAVE_GSSAPI */
341 #endif /* CURL_DISABLE_FTP */