1 /* GSSAPI/krb5 support for FTP - loosely based on old krb4.c
3 * Copyright (c) 1995, 1996, 1997, 1998, 1999 Kungliga Tekniska Högskolan
4 * (Royal Institute of Technology, Stockholm, Sweden).
5 * Copyright (c) 2004 - 2011 Daniel Stenberg
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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
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28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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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"
57 #define _MPRINTF_REPLACE /* use our functions only */
58 #include <curl/mprintf.h>
60 /* The last #include file should be: */
63 #define LOCAL_ADDR (&conn->local_addr)
64 #define REMOTE_ADDR conn->ip_addr->ai_addr
67 krb5_init(void *app_data)
69 gss_ctx_id_t *context = app_data;
70 /* Make sure our context is initialized for krb5_end. */
71 *context = GSS_C_NO_CONTEXT;
76 krb5_check_prot(void *app_data, int level)
78 (void)app_data; /* unused */
79 if(level == PROT_CONFIDENTIAL)
85 krb5_decode(void *app_data, void *buf, int len,
86 int level UNUSED_PARAM,
87 struct connectdata *conn UNUSED_PARAM)
89 gss_ctx_id_t *context = app_data;
91 gss_buffer_desc enc, dec;
98 maj = gss_unseal(&min, *context, &enc, &dec, NULL, NULL);
99 if(maj != GSS_S_COMPLETE) {
105 memcpy(buf, dec.value, dec.length);
107 gss_release_buffer(&min, &dec);
113 krb5_overhead(void *app_data, int level, int len)
115 /* no arguments are used */
123 krb5_encode(void *app_data, const void *from, int length, int level, void **to,
124 struct connectdata *conn UNUSED_PARAM)
126 gss_ctx_id_t *context = app_data;
127 gss_buffer_desc dec, enc;
135 /* NOTE that the cast is safe, neither of the krb5, gnu gss and heimdal
136 * libraries modify the input buffer in gss_seal()
138 dec.value = (void*)from;
140 maj = gss_seal(&min, *context,
141 level == PROT_PRIVATE,
145 if(maj != GSS_S_COMPLETE)
148 /* malloc a new buffer, in case gss_release_buffer doesn't work as
150 *to = malloc(enc.length);
153 memcpy(*to, enc.value, enc.length);
155 gss_release_buffer(&min, &enc);
160 krb5_auth(void *app_data, struct connectdata *conn)
164 const char *host = conn->host.name;
166 curl_socklen_t l = sizeof(conn->local_addr);
167 struct SessionHandle *data = conn->data;
169 const char *service = "ftp", *srv_host = "host";
170 gss_buffer_desc input_buffer, output_buffer, _gssresp, *gssresp;
173 gss_ctx_id_t *context = app_data;
174 struct gss_channel_bindings_struct chan;
175 size_t base64_sz = 0;
177 if(getsockname(conn->sock[FIRSTSOCKET],
178 (struct sockaddr *)LOCAL_ADDR, &l) < 0)
179 perror("getsockname()");
181 chan.initiator_addrtype = GSS_C_AF_INET;
182 chan.initiator_address.length = l - 4;
183 chan.initiator_address.value =
184 &((struct sockaddr_in *)LOCAL_ADDR)->sin_addr.s_addr;
185 chan.acceptor_addrtype = GSS_C_AF_INET;
186 chan.acceptor_address.length = l - 4;
187 chan.acceptor_address.value =
188 &((struct sockaddr_in *)REMOTE_ADDR)->sin_addr.s_addr;
189 chan.application_data.length = 0;
190 chan.application_data.value = NULL;
192 /* this loop will execute twice (once for service, once for host) */
194 /* this really shouldn't be repeated here, but can't help it */
195 if(service == srv_host) {
196 result = Curl_ftpsendf(conn, "AUTH GSSAPI");
200 if(Curl_GetFTPResponse(&nread, conn, NULL))
203 if(data->state.buffer[0] != '3')
207 input_buffer.value = data->state.buffer;
208 input_buffer.length = snprintf(input_buffer.value, BUFSIZE, "%s@%s",
210 maj = gss_import_name(&min, &input_buffer, GSS_C_NT_HOSTBASED_SERVICE,
212 if(maj != GSS_S_COMPLETE) {
213 gss_release_name(&min, &gssname);
214 if(service == srv_host) {
215 Curl_failf(data, "Error importing service name %s",
222 /* We pass NULL as |output_name_type| to avoid a leak. */
223 gss_display_name(&min, gssname, &output_buffer, NULL);
224 Curl_infof(data, "Trying against %s\n", output_buffer.value);
225 gssresp = GSS_C_NO_BUFFER;
226 *context = GSS_C_NO_CONTEXT;
229 /* Release the buffer at each iteration to avoid leaking: the first time
230 we are releasing the memory from gss_display_name. The last item is
231 taken care by a final gss_release_buffer. */
232 gss_release_buffer(&min, &output_buffer);
234 maj = Curl_gss_init_sec_context(data,
244 free(_gssresp.value);
249 Curl_infof(data, "Error creating security context\n");
254 if(output_buffer.length != 0) {
255 result = Curl_base64_encode(data, (char *)output_buffer.value,
256 output_buffer.length, &p, &base64_sz);
258 Curl_infof(data,"base64-encoding: %s\n", curl_easy_strerror(result));
263 result = Curl_ftpsendf(conn, "ADAT %s", p);
272 if(Curl_GetFTPResponse(&nread, conn, NULL)) {
277 if(data->state.buffer[0] != '2' && data->state.buffer[0] != '3') {
278 Curl_infof(data, "Server didn't accept auth data\n");
283 p = data->state.buffer + 4;
284 p = strstr(p, "ADAT=");
286 result = Curl_base64_decode(p + 5,
287 (unsigned char **)&_gssresp.value,
290 Curl_failf(data,"base64-decoding: %s", curl_easy_strerror(result));
298 } while(maj == GSS_S_CONTINUE_NEEDED);
300 gss_release_name(&min, &gssname);
301 gss_release_buffer(&min, &output_buffer);
304 free(_gssresp.value);
306 if(ret == AUTH_OK || service == srv_host)
314 static void krb5_end(void *app_data)
317 gss_ctx_id_t *context = app_data;
318 if(*context != GSS_C_NO_CONTEXT) {
319 maj = gss_delete_sec_context(&min, context, GSS_C_NO_BUFFER);
320 DEBUGASSERT(maj == GSS_S_COMPLETE);
324 struct Curl_sec_client_mech Curl_krb5_client_mech = {
326 sizeof(gss_ctx_id_t),
336 #endif /* HAVE_GSSAPI */
337 #endif /* CURL_DISABLE_FTP */