2 Unix SMB/CIFS implementation.
3 SMB Transport encryption (sealing) code.
4 Copyright (C) Jeremy Allison 2007.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 /******************************************************************************
24 Pull out the encryption context for this packet. 0 means global context.
25 ******************************************************************************/
27 NTSTATUS get_enc_ctx_num(char *buf, uint16 *p_enc_ctx_num)
29 if (smb_len(buf) < 8) {
30 return NT_STATUS_INVALID_BUFFER_SIZE;
33 if (buf[4] == (char)0xFF) {
34 if (buf[5] == 'S' && buf [6] == 'M' && buf[7] == 'B') {
35 /* Not an encrypted buffer. */
36 return NT_STATUS_NOT_FOUND;
39 *p_enc_ctx_num = SVAL(buf,6);
43 return NT_STATUS_INVALID_NETWORK_RESPONSE;
46 /******************************************************************************
47 Generic code for client and server.
48 Is encryption turned on ?
49 ******************************************************************************/
51 BOOL common_encryption_on(struct smb_trans_enc_state *es)
53 return ((es != NULL) && es->enc_on);
56 /******************************************************************************
57 Generic code for client and server.
58 NTLM decrypt an incoming buffer.
59 Abartlett tells me that SSPI puts the signature first before the encrypted
60 output, so cope with the same for compatibility.
61 ******************************************************************************/
63 NTSTATUS common_ntlm_decrypt_buffer(NTLMSSP_STATE *ntlmssp_state, char *buf)
66 size_t buf_len = smb_len(buf) + 4; /* Don't forget the 4 length bytes. */
71 if (buf_len < 8 + NTLMSSP_SIG_SIZE) {
72 return NT_STATUS_BUFFER_TOO_SMALL;
75 inbuf = smb_xmemdup(buf, buf_len);
77 /* Adjust for the signature. */
78 data_len = buf_len - 8 - NTLMSSP_SIG_SIZE;
80 /* Point at the signature. */
81 sig = data_blob_const(inbuf+8, NTLMSSP_SIG_SIZE);
83 status = ntlmssp_unseal_packet(ntlmssp_state,
84 (unsigned char *)inbuf + 8 + NTLMSSP_SIG_SIZE, /* 4 byte len + 0xFF 'E' <enc> <ctx> */
86 (unsigned char *)inbuf + 8 + NTLMSSP_SIG_SIZE,
90 if (!NT_STATUS_IS_OK(status)) {
95 memcpy(buf + 8, inbuf + 8 + NTLMSSP_SIG_SIZE, data_len);
98 /* Reset the length. */
99 smb_setlen(buf, data_len + 4);
103 /******************************************************************************
104 Generic code for client and server.
105 NTLM encrypt an outgoing buffer. Return the encrypted pointer in ppbuf_out.
106 Abartlett tells me that SSPI puts the signature first before the encrypted
107 output, so do the same for compatibility.
108 ******************************************************************************/
110 NTSTATUS common_ntlm_encrypt_buffer(NTLMSSP_STATE *ntlmssp_state,
117 size_t data_len = smb_len(buf) - 4; /* Ignore the 0xFF SMB bytes. */
123 return NT_STATUS_BUFFER_TOO_SMALL;
127 * We know smb_len can't return a value > 128k, so no int overflow
131 buf_out = SMB_XMALLOC_ARRAY(char, 8 + NTLMSSP_SIG_SIZE + data_len);
133 /* Copy the data from the original buffer. */
135 memcpy(buf_out + 8 + NTLMSSP_SIG_SIZE, buf + 8, data_len);
137 smb_set_enclen(buf_out, smb_len(buf) + NTLMSSP_SIG_SIZE, enc_ctx_num);
139 sig = data_blob(NULL, NTLMSSP_SIG_SIZE);
141 status = ntlmssp_seal_packet(ntlmssp_state,
142 (unsigned char *)buf_out + 8 + NTLMSSP_SIG_SIZE, /* 4 byte len + 0xFF 'S' <enc> <ctx> */
144 (unsigned char *)buf_out + 8 + NTLMSSP_SIG_SIZE,
148 if (!NT_STATUS_IS_OK(status)) {
149 data_blob_free(&sig);
154 /* First 16 data bytes are signature for SSPI compatibility. */
155 memcpy(buf_out + 8, sig.data, NTLMSSP_SIG_SIZE);
156 *ppbuf_out = buf_out;
160 /******************************************************************************
161 Generic code for client and server.
162 gss-api decrypt an incoming buffer. We insist that the size of the
163 unwrapped buffer must be smaller or identical to the incoming buffer.
164 ******************************************************************************/
166 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
167 static NTSTATUS common_gss_decrypt_buffer(struct smb_tran_enc_state_gss *gss_state, char *buf)
169 gss_ctx_id_t gss_ctx = gss_state->gss_ctx;
173 gss_buffer_desc in_buf, out_buf;
174 size_t buf_len = smb_len(buf) + 4; /* Don't forget the 4 length bytes. */
177 return NT_STATUS_BUFFER_TOO_SMALL;
180 in_buf.value = buf + 8;
181 in_buf.length = buf_len - 8;
183 ret = gss_unwrap(&minor,
187 &flags_got, /* did we get sign+seal ? */
190 if (ret != GSS_S_COMPLETE) {
191 ADS_STATUS adss = ADS_ERROR_GSS(ret, minor);
192 DEBUG(0,("common_gss_encrypt_buffer: gss_unwrap failed. Error %s\n",
194 /* Um - no mapping for gss-errs to NTSTATUS yet. */
195 return ads_ntstatus(adss);
198 if (out_buf.length > in_buf.length) {
199 DEBUG(0,("common_gss_encrypt_buffer: gss_unwrap size (%u) too large (%u) !\n",
200 (unsigned int)out_buf.length,
201 (unsigned int)in_buf.length ));
202 gss_release_buffer(&minor, &out_buf);
203 return NT_STATUS_INVALID_PARAMETER;
206 memcpy(buf + 8, out_buf.value, out_buf.length);
207 smb_setlen(buf, out_buf.length + 4);
209 gss_release_buffer(&minor, &out_buf);
213 /******************************************************************************
214 Generic code for client and server.
215 gss-api encrypt an outgoing buffer. Return the alloced encrypted pointer in buf_out.
216 ******************************************************************************/
218 static NTSTATUS common_gss_encrypt_buffer(struct smb_tran_enc_state_gss *gss_state,
223 gss_ctx_id_t gss_ctx = gss_state->gss_ctx;
227 gss_buffer_desc in_buf, out_buf;
228 size_t buf_len = smb_len(buf) + 4; /* Don't forget the 4 length bytes. */
233 return NT_STATUS_BUFFER_TOO_SMALL;
236 in_buf.value = buf + 8;
237 in_buf.length = buf_len - 8;
239 ret = gss_wrap(&minor,
241 True, /* we want sign+seal. */
244 &flags_got, /* did we get sign+seal ? */
247 if (ret != GSS_S_COMPLETE) {
248 ADS_STATUS adss = ADS_ERROR_GSS(ret, minor);
249 DEBUG(0,("common_gss_encrypt_buffer: gss_wrap failed. Error %s\n",
251 /* Um - no mapping for gss-errs to NTSTATUS yet. */
252 return ads_ntstatus(adss);
256 /* Sign+seal not supported. */
257 gss_release_buffer(&minor, &out_buf);
258 return NT_STATUS_NOT_SUPPORTED;
261 /* Ya see - this is why I *hate* gss-api. I don't
262 * want to have to malloc another buffer of the
263 * same size + 8 bytes just to get a continuous
264 * header + buffer, but gss won't let me pass in
265 * a pre-allocated buffer. Bastards (and you know
266 * who you are....). I might fix this by
267 * going to "encrypt_and_send" passing in a file
268 * descriptor and doing scatter-gather write with
269 * TCP cork on Linux. But I shouldn't have to
273 *ppbuf_out = SMB_MALLOC(out_buf.length + 8); /* We know this can't wrap. */
275 gss_release_buffer(&minor, &out_buf);
276 return NT_STATUS_NO_MEMORY;
279 memcpy(*ppbuf_out+8, out_buf.value, out_buf.length);
280 smb_set_enclen(*ppbuf_out, out_buf.length + 4, enc_ctx_num);
282 gss_release_buffer(&minor, &out_buf);
287 /******************************************************************************
288 Generic code for client and server.
289 Encrypt an outgoing buffer. Return the alloced encrypted pointer in buf_out.
290 ******************************************************************************/
292 NTSTATUS common_encrypt_buffer(struct smb_trans_enc_state *es, char *buffer, char **buf_out)
294 if (!common_encryption_on(es)) {
295 /* Not encrypting. */
300 switch (es->smb_enc_type) {
301 case SMB_TRANS_ENC_NTLM:
302 return common_ntlm_encrypt_buffer(es->s.ntlmssp_state, es->enc_ctx_num, buffer, buf_out);
303 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
304 case SMB_TRANS_ENC_GSS:
305 return common_gss_encrypt_buffer(es->s.gss_state, es->enc_ctx_num, buffer, buf_out);
308 return NT_STATUS_NOT_SUPPORTED;
312 /******************************************************************************
313 Generic code for client and server.
314 Decrypt an incoming SMB buffer. Replaces the data within it.
315 New data must be less than or equal to the current length.
316 ******************************************************************************/
318 NTSTATUS common_decrypt_buffer(struct smb_trans_enc_state *es, char *buf)
320 if (!common_encryption_on(es)) {
321 /* Not decrypting. */
325 switch (es->smb_enc_type) {
326 case SMB_TRANS_ENC_NTLM:
327 return common_ntlm_decrypt_buffer(es->s.ntlmssp_state, buf);
328 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
329 case SMB_TRANS_ENC_GSS:
330 return common_gss_decrypt_buffer(es->s.gss_state, buf);
333 return NT_STATUS_NOT_SUPPORTED;
337 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
338 /******************************************************************************
339 Shutdown a gss encryption state.
340 ******************************************************************************/
342 static void common_free_gss_state(struct smb_tran_enc_state_gss **pp_gss_state)
345 struct smb_tran_enc_state_gss *gss_state = *pp_gss_state;
347 if (gss_state->creds != GSS_C_NO_CREDENTIAL) {
348 gss_release_cred(&minor, &gss_state->creds);
350 if (gss_state->gss_ctx != GSS_C_NO_CONTEXT) {
351 gss_delete_sec_context(&minor, &gss_state->gss_ctx, NULL);
353 SAFE_FREE(*pp_gss_state);
357 /******************************************************************************
358 Shutdown an encryption state.
359 ******************************************************************************/
361 void common_free_encryption_state(struct smb_trans_enc_state **pp_es)
363 struct smb_trans_enc_state *es = *pp_es;
369 if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
370 if (es->s.ntlmssp_state) {
371 ntlmssp_end(&es->s.ntlmssp_state);
374 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
375 if (es->smb_enc_type == SMB_TRANS_ENC_GSS) {
376 /* Free the gss context handle. */
377 if (es->s.gss_state) {
378 common_free_gss_state(&es->s.gss_state);
386 /******************************************************************************
387 Free an encryption-allocated buffer.
388 ******************************************************************************/
390 void common_free_enc_buffer(struct smb_trans_enc_state *es, char *buf)
392 if (!common_encryption_on(es)) {
396 if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
401 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
402 if (es->smb_enc_type == SMB_TRANS_ENC_GSS) {
404 gss_buffer_desc rel_buf;
406 rel_buf.length = smb_len(buf) + 4;
407 gss_release_buffer(&min, &rel_buf);
412 /******************************************************************************
413 Client side encryption.
414 ******************************************************************************/
416 /******************************************************************************
417 Is client encryption on ?
418 ******************************************************************************/
420 BOOL cli_encryption_on(struct cli_state *cli)
422 /* If we supported multiple encrytion contexts
423 * here we'd look up based on tid.
425 return common_encryption_on(cli->trans_enc_state);
428 /******************************************************************************
429 Shutdown a client encryption state.
430 ******************************************************************************/
432 void cli_free_encryption_context(struct cli_state *cli)
434 common_free_encryption_state(&cli->trans_enc_state);
437 /******************************************************************************
438 Free an encryption-allocated buffer.
439 ******************************************************************************/
441 void cli_free_enc_buffer(struct cli_state *cli, char *buf)
443 /* We know this is an smb buffer, and we
444 * didn't malloc, only copy, for a keepalive,
445 * so ignore session keepalives. */
447 if(CVAL(buf,0) == SMBkeepalive) {
451 /* If we supported multiple encrytion contexts
452 * here we'd look up based on tid.
454 common_free_enc_buffer(cli->trans_enc_state, buf);
457 /******************************************************************************
458 Decrypt an incoming buffer.
459 ******************************************************************************/
461 NTSTATUS cli_decrypt_message(struct cli_state *cli)
466 /* Ignore session keepalives. */
467 if(CVAL(cli->inbuf,0) == SMBkeepalive) {
471 status = get_enc_ctx_num(cli->inbuf, &enc_ctx_num);
472 if (!NT_STATUS_IS_OK(status)) {
476 if (enc_ctx_num != cli->trans_enc_state->enc_ctx_num) {
477 return NT_STATUS_INVALID_HANDLE;
480 return common_decrypt_buffer(cli->trans_enc_state, cli->inbuf);
483 /******************************************************************************
484 Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
485 ******************************************************************************/
487 NTSTATUS cli_encrypt_message(struct cli_state *cli, char **buf_out)
489 /* Ignore session keepalives. */
490 if(CVAL(cli->outbuf,0) == SMBkeepalive) {
494 /* If we supported multiple encrytion contexts
495 * here we'd look up based on tid.
497 return common_encrypt_buffer(cli->trans_enc_state, cli->outbuf, buf_out);