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
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13 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
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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
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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
49 #include "curl_base64.h"
51 #include "curl_gssapi.h"
54 #include "curl_memory.h"
56 #define _MPRINTF_REPLACE /* use our functions only */
57 #include <curl/mprintf.h>
59 /* The last #include file should be: */
62 #define LOCAL_ADDR (&conn->local_addr)
63 #define REMOTE_ADDR conn->ip_addr->ai_addr
66 krb5_init(void *app_data)
68 gss_ctx_id_t *context = app_data;
69 /* Make sure our context is initialized for krb5_end. */
70 *context = GSS_C_NO_CONTEXT;
75 krb5_check_prot(void *app_data, int level)
77 (void)app_data; /* unused */
78 if(level == PROT_CONFIDENTIAL)
84 krb5_decode(void *app_data, void *buf, int len,
85 int level UNUSED_PARAM,
86 struct connectdata *conn UNUSED_PARAM)
88 gss_ctx_id_t *context = app_data;
90 gss_buffer_desc enc, dec;
97 maj = gss_unseal(&min, *context, &enc, &dec, NULL, NULL);
98 if(maj != GSS_S_COMPLETE) {
104 memcpy(buf, dec.value, dec.length);
106 gss_release_buffer(&min, &dec);
112 krb5_overhead(void *app_data, int level, int len)
114 /* no arguments are used */
122 krb5_encode(void *app_data, const void *from, int length, int level, void **to,
123 struct connectdata *conn UNUSED_PARAM)
125 gss_ctx_id_t *context = app_data;
126 gss_buffer_desc dec, enc;
134 /* NOTE that the cast is safe, neither of the krb5, gnu gss and heimdal
135 * libraries modify the input buffer in gss_seal()
137 dec.value = (void*)from;
139 maj = gss_seal(&min, *context,
140 level == PROT_PRIVATE,
144 if(maj != GSS_S_COMPLETE)
147 /* malloc a new buffer, in case gss_release_buffer doesn't work as
149 *to = malloc(enc.length);
152 memcpy(*to, enc.value, enc.length);
154 gss_release_buffer(&min, &enc);
159 krb5_auth(void *app_data, struct connectdata *conn)
163 const char *host = conn->host.name;
165 curl_socklen_t l = sizeof(conn->local_addr);
166 struct SessionHandle *data = conn->data;
168 const char *service = "ftp", *srv_host = "host";
169 gss_buffer_desc input_buffer, output_buffer, _gssresp, *gssresp;
172 gss_ctx_id_t *context = app_data;
173 struct gss_channel_bindings_struct chan;
175 if(getsockname(conn->sock[FIRSTSOCKET],
176 (struct sockaddr *)LOCAL_ADDR, &l) < 0)
177 perror("getsockname()");
179 chan.initiator_addrtype = GSS_C_AF_INET;
180 chan.initiator_address.length = l - 4;
181 chan.initiator_address.value =
182 &((struct sockaddr_in *)LOCAL_ADDR)->sin_addr.s_addr;
183 chan.acceptor_addrtype = GSS_C_AF_INET;
184 chan.acceptor_address.length = l - 4;
185 chan.acceptor_address.value =
186 &((struct sockaddr_in *)REMOTE_ADDR)->sin_addr.s_addr;
187 chan.application_data.length = 0;
188 chan.application_data.value = NULL;
190 /* this loop will execute twice (once for service, once for host) */
192 /* this really shouldn't be repeated here, but can't help it */
193 if(service == srv_host) {
194 result = Curl_ftpsendf(conn, "AUTH GSSAPI");
198 if(Curl_GetFTPResponse(&nread, conn, NULL))
201 if(data->state.buffer[0] != '3')
205 input_buffer.value = data->state.buffer;
206 input_buffer.length = snprintf(input_buffer.value, BUFSIZE, "%s@%s",
208 maj = gss_import_name(&min, &input_buffer, GSS_C_NT_HOSTBASED_SERVICE,
210 if(maj != GSS_S_COMPLETE) {
211 gss_release_name(&min, &gssname);
212 if(service == srv_host) {
213 Curl_failf(data, "Error importing service name %s",
220 /* We pass NULL as |output_name_type| to avoid a leak. */
221 gss_display_name(&min, gssname, &output_buffer, NULL);
222 Curl_infof(data, "Trying against %s\n", output_buffer.value);
223 gssresp = GSS_C_NO_BUFFER;
224 *context = GSS_C_NO_CONTEXT;
227 /* Release the buffer at each iteration to avoid leaking: the first time
228 we are releasing the memory from gss_display_name. The last item is
229 taken care by a final gss_release_buffer. */
230 gss_release_buffer(&min, &output_buffer);
232 maj = Curl_gss_init_sec_context(&min,
241 free(_gssresp.value);
246 Curl_infof(data, "Error creating security context\n");
251 if(output_buffer.length != 0) {
252 if(Curl_base64_encode(data, (char *)output_buffer.value,
253 output_buffer.length, &p) < 1) {
254 Curl_infof(data, "Out of memory base64-encoding\n");
259 result = Curl_ftpsendf(conn, "ADAT %s", p);
268 if(Curl_GetFTPResponse(&nread, conn, NULL)) {
273 if(data->state.buffer[0] != '2' && data->state.buffer[0] != '3') {
274 Curl_infof(data, "Server didn't accept auth data\n");
279 p = data->state.buffer + 4;
280 p = strstr(p, "ADAT=");
282 _gssresp.length = Curl_base64_decode(p + 5, (unsigned char **)
284 if(_gssresp.length < 1) {
285 Curl_failf(data, "Out of memory base64-encoding\n");
293 } while(maj == GSS_S_CONTINUE_NEEDED);
295 gss_release_name(&min, &gssname);
296 gss_release_buffer(&min, &output_buffer);
299 free(_gssresp.value);
301 if(ret == AUTH_OK || service == srv_host)
309 static void krb5_end(void *app_data)
312 gss_ctx_id_t *context = app_data;
313 if(*context != GSS_C_NO_CONTEXT) {
314 maj = gss_delete_sec_context(&min, context, GSS_C_NO_BUFFER);
315 DEBUGASSERT(maj == GSS_S_COMPLETE);
319 struct Curl_sec_client_mech Curl_krb5_client_mech = {
321 sizeof(gss_ctx_id_t),
331 #endif /* HAVE_GSSAPI */
332 #endif /* CURL_DISABLE_FTP */