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diff --git a/source3/libsmb/smb_seal.c b/source3/libsmb/smb_seal.c
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+/*
+ Unix SMB/CIFS implementation.
+ SMB Transport encryption (sealing) code.
+ Copyright (C) Jeremy Allison 2007.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+
+/******************************************************************************
+ Pull out the encryption context for this packet. 0 means global context.
+******************************************************************************/
+
+NTSTATUS get_enc_ctx_num(const uint8_t *buf, uint16 *p_enc_ctx_num)
+{
+ if (smb_len(buf) < 8) {
+ return NT_STATUS_INVALID_BUFFER_SIZE;
+ }
+
+ if (buf[4] == 0xFF) {
+ if (buf[5] == 'S' && buf [6] == 'M' && buf[7] == 'B') {
+ /* Not an encrypted buffer. */
+ return NT_STATUS_NOT_FOUND;
+ }
+ if (buf[5] == 'E') {
+ *p_enc_ctx_num = SVAL(buf,6);
+ return NT_STATUS_OK;
+ }
+ }
+ return NT_STATUS_INVALID_NETWORK_RESPONSE;
+}
+
+/******************************************************************************
+ Generic code for client and server.
+ Is encryption turned on ?
+******************************************************************************/
+
+bool common_encryption_on(struct smb_trans_enc_state *es)
+{
+ return ((es != NULL) && es->enc_on);
+}
+
+/******************************************************************************
+ Generic code for client and server.
+ NTLM decrypt an incoming buffer.
+ Abartlett tells me that SSPI puts the signature first before the encrypted
+ output, so cope with the same for compatibility.
+******************************************************************************/
+
+NTSTATUS common_ntlm_decrypt_buffer(NTLMSSP_STATE *ntlmssp_state, char *buf)
+{
+ NTSTATUS status;
+ size_t buf_len = smb_len(buf) + 4; /* Don't forget the 4 length bytes. */
+ size_t data_len;
+ char *inbuf;
+ DATA_BLOB sig;
+
+ if (buf_len < 8 + NTLMSSP_SIG_SIZE) {
+ return NT_STATUS_BUFFER_TOO_SMALL;
+ }
+
+ inbuf = (char *)smb_xmemdup(buf, buf_len);
+
+ /* Adjust for the signature. */
+ data_len = buf_len - 8 - NTLMSSP_SIG_SIZE;
+
+ /* Point at the signature. */
+ sig = data_blob_const(inbuf+8, NTLMSSP_SIG_SIZE);
+
+ status = ntlmssp_unseal_packet(ntlmssp_state,
+ (unsigned char *)inbuf + 8 + NTLMSSP_SIG_SIZE, /* 4 byte len + 0xFF 'E' <enc> <ctx> */
+ data_len,
+ (unsigned char *)inbuf + 8 + NTLMSSP_SIG_SIZE,
+ data_len,
+ &sig);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ SAFE_FREE(inbuf);
+ return status;
+ }
+
+ memcpy(buf + 8, inbuf + 8 + NTLMSSP_SIG_SIZE, data_len);
+
+ /* Reset the length and overwrite the header. */
+ smb_setlen(buf,data_len + 4);
+
+ SAFE_FREE(inbuf);
+ return NT_STATUS_OK;
+}
+
+/******************************************************************************
+ Generic code for client and server.
+ NTLM encrypt an outgoing buffer. Return the encrypted pointer in ppbuf_out.
+ Abartlett tells me that SSPI puts the signature first before the encrypted
+ output, so do the same for compatibility.
+******************************************************************************/
+
+NTSTATUS common_ntlm_encrypt_buffer(NTLMSSP_STATE *ntlmssp_state,
+ uint16 enc_ctx_num,
+ char *buf,
+ char **ppbuf_out)
+{
+ NTSTATUS status;
+ char *buf_out;
+ size_t data_len = smb_len(buf) - 4; /* Ignore the 0xFF SMB bytes. */
+ DATA_BLOB sig;
+
+ *ppbuf_out = NULL;
+
+ if (data_len == 0) {
+ return NT_STATUS_BUFFER_TOO_SMALL;
+ }
+
+ /*
+ * We know smb_len can't return a value > 128k, so no int overflow
+ * check needed.
+ */
+
+ buf_out = SMB_XMALLOC_ARRAY(char, 8 + NTLMSSP_SIG_SIZE + data_len);
+
+ /* Copy the data from the original buffer. */
+
+ memcpy(buf_out + 8 + NTLMSSP_SIG_SIZE, buf + 8, data_len);
+
+ smb_set_enclen(buf_out, smb_len(buf) + NTLMSSP_SIG_SIZE, enc_ctx_num);
+
+ sig = data_blob(NULL, NTLMSSP_SIG_SIZE);
+
+ status = ntlmssp_seal_packet(ntlmssp_state,
+ (unsigned char *)buf_out + 8 + NTLMSSP_SIG_SIZE, /* 4 byte len + 0xFF 'S' <enc> <ctx> */
+ data_len,
+ (unsigned char *)buf_out + 8 + NTLMSSP_SIG_SIZE,
+ data_len,
+ &sig);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ data_blob_free(&sig);
+ SAFE_FREE(buf_out);
+ return status;
+ }
+
+ /* First 16 data bytes are signature for SSPI compatibility. */
+ memcpy(buf_out + 8, sig.data, NTLMSSP_SIG_SIZE);
+ *ppbuf_out = buf_out;
+ return NT_STATUS_OK;
+}
+
+/******************************************************************************
+ Generic code for client and server.
+ gss-api decrypt an incoming buffer. We insist that the size of the
+ unwrapped buffer must be smaller or identical to the incoming buffer.
+******************************************************************************/
+
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+static NTSTATUS common_gss_decrypt_buffer(struct smb_tran_enc_state_gss *gss_state, char *buf)
+{
+ gss_ctx_id_t gss_ctx = gss_state->gss_ctx;
+ OM_uint32 ret = 0;
+ OM_uint32 minor = 0;
+ int flags_got = 0;
+ gss_buffer_desc in_buf, out_buf;
+ size_t buf_len = smb_len(buf) + 4; /* Don't forget the 4 length bytes. */
+
+ if (buf_len < 8) {
+ return NT_STATUS_BUFFER_TOO_SMALL;
+ }
+
+ in_buf.value = buf + 8;
+ in_buf.length = buf_len - 8;
+
+ ret = gss_unwrap(&minor,
+ gss_ctx,
+ &in_buf,
+ &out_buf,
+ &flags_got, /* did we get sign+seal ? */
+ (gss_qop_t *) NULL);
+
+ if (ret != GSS_S_COMPLETE) {
+ ADS_STATUS adss = ADS_ERROR_GSS(ret, minor);
+ DEBUG(0,("common_gss_encrypt_buffer: gss_unwrap failed. Error %s\n",
+ ads_errstr(adss) ));
+ return map_nt_error_from_gss(ret, minor);
+ }
+
+ if (out_buf.length > in_buf.length) {
+ DEBUG(0,("common_gss_encrypt_buffer: gss_unwrap size (%u) too large (%u) !\n",
+ (unsigned int)out_buf.length,
+ (unsigned int)in_buf.length ));
+ gss_release_buffer(&minor, &out_buf);
+ return NT_STATUS_INVALID_PARAMETER;
+ }
+
+ memcpy(buf + 8, out_buf.value, out_buf.length);
+ /* Reset the length and overwrite the header. */
+ smb_setlen(buf, out_buf.length + 4);
+
+ gss_release_buffer(&minor, &out_buf);
+ return NT_STATUS_OK;
+}
+
+/******************************************************************************
+ Generic code for client and server.
+ gss-api encrypt an outgoing buffer. Return the alloced encrypted pointer in buf_out.
+******************************************************************************/
+
+static NTSTATUS common_gss_encrypt_buffer(struct smb_tran_enc_state_gss *gss_state,
+ uint16 enc_ctx_num,
+ char *buf,
+ char **ppbuf_out)
+{
+ gss_ctx_id_t gss_ctx = gss_state->gss_ctx;
+ OM_uint32 ret = 0;
+ OM_uint32 minor = 0;
+ int flags_got = 0;
+ gss_buffer_desc in_buf, out_buf;
+ size_t buf_len = smb_len(buf) + 4; /* Don't forget the 4 length bytes. */
+
+ *ppbuf_out = NULL;
+
+ if (buf_len < 8) {
+ return NT_STATUS_BUFFER_TOO_SMALL;
+ }
+
+ in_buf.value = buf + 8;
+ in_buf.length = buf_len - 8;
+
+ ret = gss_wrap(&minor,
+ gss_ctx,
+ true, /* we want sign+seal. */
+ GSS_C_QOP_DEFAULT,
+ &in_buf,
+ &flags_got, /* did we get sign+seal ? */
+ &out_buf);
+
+ if (ret != GSS_S_COMPLETE) {
+ ADS_STATUS adss = ADS_ERROR_GSS(ret, minor);
+ DEBUG(0,("common_gss_encrypt_buffer: gss_wrap failed. Error %s\n",
+ ads_errstr(adss) ));
+ return map_nt_error_from_gss(ret, minor);
+ }
+
+ if (!flags_got) {
+ /* Sign+seal not supported. */
+ gss_release_buffer(&minor, &out_buf);
+ return NT_STATUS_NOT_SUPPORTED;
+ }
+
+ /* Ya see - this is why I *hate* gss-api. I don't
+ * want to have to malloc another buffer of the
+ * same size + 8 bytes just to get a continuous
+ * header + buffer, but gss won't let me pass in
+ * a pre-allocated buffer. Bastards (and you know
+ * who you are....). I might fix this by
+ * going to "encrypt_and_send" passing in a file
+ * descriptor and doing scatter-gather write with
+ * TCP cork on Linux. But I shouldn't have to
+ * bother :-*(. JRA.
+ */
+
+ *ppbuf_out = (char *)SMB_MALLOC(out_buf.length + 8); /* We know this can't wrap. */
+ if (!*ppbuf_out) {
+ gss_release_buffer(&minor, &out_buf);
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ memcpy(*ppbuf_out+8, out_buf.value, out_buf.length);
+ smb_set_enclen(*ppbuf_out, out_buf.length + 4, enc_ctx_num);
+
+ gss_release_buffer(&minor, &out_buf);
+ return NT_STATUS_OK;
+}
+#endif
+
+/******************************************************************************
+ Generic code for client and server.
+ Encrypt an outgoing buffer. Return the alloced encrypted pointer in buf_out.
+******************************************************************************/
+
+NTSTATUS common_encrypt_buffer(struct smb_trans_enc_state *es, char *buffer, char **buf_out)
+{
+ if (!common_encryption_on(es)) {
+ /* Not encrypting. */
+ *buf_out = buffer;
+ return NT_STATUS_OK;
+ }
+
+ switch (es->smb_enc_type) {
+ case SMB_TRANS_ENC_NTLM:
+ return common_ntlm_encrypt_buffer(es->s.ntlmssp_state, es->enc_ctx_num, buffer, buf_out);
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+ case SMB_TRANS_ENC_GSS:
+ return common_gss_encrypt_buffer(es->s.gss_state, es->enc_ctx_num, buffer, buf_out);
+#endif
+ default:
+ return NT_STATUS_NOT_SUPPORTED;
+ }
+}
+
+/******************************************************************************
+ Generic code for client and server.
+ Decrypt an incoming SMB buffer. Replaces the data within it.
+ New data must be less than or equal to the current length.
+******************************************************************************/
+
+NTSTATUS common_decrypt_buffer(struct smb_trans_enc_state *es, char *buf)
+{
+ if (!common_encryption_on(es)) {
+ /* Not decrypting. */
+ return NT_STATUS_OK;
+ }
+
+ switch (es->smb_enc_type) {
+ case SMB_TRANS_ENC_NTLM:
+ return common_ntlm_decrypt_buffer(es->s.ntlmssp_state, buf);
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+ case SMB_TRANS_ENC_GSS:
+ return common_gss_decrypt_buffer(es->s.gss_state, buf);
+#endif
+ default:
+ return NT_STATUS_NOT_SUPPORTED;
+ }
+}
+
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+/******************************************************************************
+ Shutdown a gss encryption state.
+******************************************************************************/
+
+static void common_free_gss_state(struct smb_tran_enc_state_gss **pp_gss_state)
+{
+ OM_uint32 minor = 0;
+ struct smb_tran_enc_state_gss *gss_state = *pp_gss_state;
+
+ if (gss_state->creds != GSS_C_NO_CREDENTIAL) {
+ gss_release_cred(&minor, &gss_state->creds);
+ }
+ if (gss_state->gss_ctx != GSS_C_NO_CONTEXT) {
+ gss_delete_sec_context(&minor, &gss_state->gss_ctx, NULL);
+ }
+ SAFE_FREE(*pp_gss_state);
+}
+#endif
+
+/******************************************************************************
+ Shutdown an encryption state.
+******************************************************************************/
+
+void common_free_encryption_state(struct smb_trans_enc_state **pp_es)
+{
+ struct smb_trans_enc_state *es = *pp_es;
+
+ if (es == NULL) {
+ return;
+ }
+
+ if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
+ if (es->s.ntlmssp_state) {
+ ntlmssp_end(&es->s.ntlmssp_state);
+ }
+ }
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+ if (es->smb_enc_type == SMB_TRANS_ENC_GSS) {
+ /* Free the gss context handle. */
+ if (es->s.gss_state) {
+ common_free_gss_state(&es->s.gss_state);
+ }
+ }
+#endif
+ SAFE_FREE(es);
+ *pp_es = NULL;
+}
+
+/******************************************************************************
+ Free an encryption-allocated buffer.
+******************************************************************************/
+
+void common_free_enc_buffer(struct smb_trans_enc_state *es, char *buf)
+{
+ if (!common_encryption_on(es)) {
+ return;
+ }
+
+ if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
+ SAFE_FREE(buf);
+ return;
+ }
+
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+ if (es->smb_enc_type == SMB_TRANS_ENC_GSS) {
+ OM_uint32 min;
+ gss_buffer_desc rel_buf;
+ rel_buf.value = buf;
+ rel_buf.length = smb_len(buf) + 4;
+ gss_release_buffer(&min, &rel_buf);
+ }
+#endif
+}
+
+/******************************************************************************
+ Client side encryption.
+******************************************************************************/
+
+/******************************************************************************
+ Is client encryption on ?
+******************************************************************************/
+
+bool cli_encryption_on(struct cli_state *cli)
+{
+ /* If we supported multiple encrytion contexts
+ * here we'd look up based on tid.
+ */
+ return common_encryption_on(cli->trans_enc_state);
+}
+
+/******************************************************************************
+ Shutdown a client encryption state.
+******************************************************************************/
+
+void cli_free_encryption_context(struct cli_state *cli)
+{
+ common_free_encryption_state(&cli->trans_enc_state);
+}
+
+/******************************************************************************
+ Free an encryption-allocated buffer.
+******************************************************************************/
+
+void cli_free_enc_buffer(struct cli_state *cli, char *buf)
+{
+ /* We know this is an smb buffer, and we
+ * didn't malloc, only copy, for a keepalive,
+ * so ignore non-session messages. */
+
+ if(CVAL(buf,0)) {
+ return;
+ }
+
+ /* If we supported multiple encrytion contexts
+ * here we'd look up based on tid.
+ */
+ common_free_enc_buffer(cli->trans_enc_state, buf);
+}
+
+/******************************************************************************
+ Decrypt an incoming buffer.
+******************************************************************************/
+
+NTSTATUS cli_decrypt_message(struct cli_state *cli)
+{
+ NTSTATUS status;
+ uint16 enc_ctx_num;
+
+ /* Ignore non-session messages. */
+ if(CVAL(cli->inbuf,0)) {
+ return NT_STATUS_OK;
+ }
+
+ status = get_enc_ctx_num((const uint8_t *)cli->inbuf, &enc_ctx_num);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+
+ if (enc_ctx_num != cli->trans_enc_state->enc_ctx_num) {
+ return NT_STATUS_INVALID_HANDLE;
+ }
+
+ return common_decrypt_buffer(cli->trans_enc_state, cli->inbuf);
+}
+
+/******************************************************************************
+ Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
+******************************************************************************/
+
+NTSTATUS cli_encrypt_message(struct cli_state *cli, char **buf_out)
+{
+ /* Ignore non-session messages. */
+ if(CVAL(cli->outbuf,0)) {
+ return NT_STATUS_OK;
+ }
+
+ /* If we supported multiple encrytion contexts
+ * here we'd look up based on tid.
+ */
+ return common_encrypt_buffer(cli->trans_enc_state, cli->outbuf, buf_out);
+}