root / vnc-auth-sasl.c @ 9399f095
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/*
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* QEMU VNC display driver: SASL auth protocol
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*
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* Copyright (C) 2009 Red Hat, Inc
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "vnc.h" |
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/* Max amount of data we send/recv for SASL steps to prevent DOS */
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#define SASL_DATA_MAX_LEN (1024 * 1024) |
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void vnc_sasl_client_cleanup(VncState *vs)
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{ |
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if (vs->sasl.conn) {
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vs->sasl.runSSF = vs->sasl.waitWriteSSF = vs->sasl.wantSSF = 0;
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vs->sasl.encodedLength = vs->sasl.encodedOffset = 0;
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vs->sasl.encoded = NULL;
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free(vs->sasl.username); |
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free(vs->sasl.mechlist); |
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vs->sasl.username = vs->sasl.mechlist = NULL;
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sasl_dispose(&vs->sasl.conn); |
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vs->sasl.conn = NULL;
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} |
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} |
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|
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|
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long vnc_client_write_sasl(VncState *vs)
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{ |
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long ret;
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VNC_DEBUG("Write SASL: Pending output %p size %d offset %d Encoded: %p size %d offset %d\n",
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vs->output.buffer, vs->output.capacity, vs->output.offset, |
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vs->sasl.encoded, vs->sasl.encodedLength, vs->sasl.encodedOffset); |
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if (!vs->sasl.encoded) {
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int err;
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err = sasl_encode(vs->sasl.conn, |
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(char *)vs->output.buffer,
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vs->output.offset, |
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(const char **)&vs->sasl.encoded, |
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&vs->sasl.encodedLength); |
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if (err != SASL_OK)
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return vnc_client_io_error(vs, -1, EIO); |
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vs->sasl.encodedOffset = 0;
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} |
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ret = vnc_client_write_buf(vs, |
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vs->sasl.encoded + vs->sasl.encodedOffset, |
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vs->sasl.encodedLength - vs->sasl.encodedOffset); |
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if (!ret)
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return 0; |
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vs->sasl.encodedOffset += ret; |
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if (vs->sasl.encodedOffset == vs->sasl.encodedLength) {
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vs->output.offset = 0;
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vs->sasl.encoded = NULL;
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vs->sasl.encodedOffset = vs->sasl.encodedLength = 0;
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} |
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/* Can't merge this block with one above, because
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* someone might have written more unencrypted
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* data in vs->output while we were processing
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* SASL encoded output
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*/
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if (vs->output.offset == 0) { |
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qemu_set_fd_handler2(vs->csock, NULL, vnc_client_read, NULL, vs); |
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} |
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return ret;
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} |
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long vnc_client_read_sasl(VncState *vs)
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{ |
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long ret;
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uint8_t encoded[4096];
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const char *decoded; |
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unsigned int decodedLen; |
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int err;
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ret = vnc_client_read_buf(vs, encoded, sizeof(encoded));
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if (!ret)
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return 0; |
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err = sasl_decode(vs->sasl.conn, |
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(char *)encoded, ret,
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&decoded, &decodedLen); |
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if (err != SASL_OK)
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return vnc_client_io_error(vs, -1, -EIO); |
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VNC_DEBUG("Read SASL Encoded %p size %ld Decoded %p size %d\n",
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encoded, ret, decoded, decodedLen); |
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buffer_reserve(&vs->input, decodedLen); |
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buffer_append(&vs->input, decoded, decodedLen); |
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return decodedLen;
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} |
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static int vnc_auth_sasl_check_access(VncState *vs) |
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{ |
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const void *val; |
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int err;
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int allow;
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err = sasl_getprop(vs->sasl.conn, SASL_USERNAME, &val); |
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if (err != SASL_OK) {
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VNC_DEBUG("cannot query SASL username on connection %d (%s), denying access\n",
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err, sasl_errstring(err, NULL, NULL)); |
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return -1; |
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} |
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if (val == NULL) { |
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VNC_DEBUG("no client username was found, denying access\n");
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return -1; |
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} |
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VNC_DEBUG("SASL client username %s\n", (const char *)val); |
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vs->sasl.username = qemu_strdup((const char*)val); |
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if (vs->vd->sasl.acl == NULL) { |
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VNC_DEBUG("no ACL activated, allowing access\n");
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return 0; |
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} |
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allow = qemu_acl_party_is_allowed(vs->vd->sasl.acl, vs->sasl.username); |
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VNC_DEBUG("SASL client %s %s by ACL\n", vs->sasl.username,
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allow ? "allowed" : "denied"); |
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return allow ? 0 : -1; |
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} |
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static int vnc_auth_sasl_check_ssf(VncState *vs) |
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{ |
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const void *val; |
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int err, ssf;
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if (!vs->sasl.wantSSF)
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return 1; |
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err = sasl_getprop(vs->sasl.conn, SASL_SSF, &val); |
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if (err != SASL_OK)
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return 0; |
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ssf = *(const int *)val; |
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VNC_DEBUG("negotiated an SSF of %d\n", ssf);
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if (ssf < 56) |
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return 0; /* 56 is good for Kerberos */ |
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/* Only setup for read initially, because we're about to send an RPC
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* reply which must be in plain text. When the next incoming RPC
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* arrives, we'll switch on writes too
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*
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* cf qemudClientReadSASL in qemud.c
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*/
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vs->sasl.runSSF = 1;
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/* We have a SSF that's good enough */
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return 1; |
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} |
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/*
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* Step Msg
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*
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* Input from client:
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*
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* u32 clientin-length
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* u8-array clientin-string
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*
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* Output to client:
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*
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* u32 serverout-length
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* u8-array serverout-strin
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* u8 continue
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*/
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static int protocol_client_auth_sasl_step_len(VncState *vs, uint8_t *data, size_t len); |
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static int protocol_client_auth_sasl_step(VncState *vs, uint8_t *data, size_t len) |
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{ |
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uint32_t datalen = len; |
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const char *serverout; |
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unsigned int serveroutlen; |
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int err;
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char *clientdata = NULL; |
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/* NB, distinction of NULL vs "" is *critical* in SASL */
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if (datalen) {
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clientdata = (char*)data;
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clientdata[datalen-1] = '\0'; /* Wire includes '\0', but make sure */ |
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datalen--; /* Don't count NULL byte when passing to _start() */
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} |
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VNC_DEBUG("Step using SASL Data %p (%d bytes)\n",
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clientdata, datalen); |
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err = sasl_server_step(vs->sasl.conn, |
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clientdata, |
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datalen, |
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&serverout, |
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&serveroutlen); |
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if (err != SASL_OK &&
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err != SASL_CONTINUE) { |
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VNC_DEBUG("sasl step failed %d (%s)\n",
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err, sasl_errdetail(vs->sasl.conn)); |
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sasl_dispose(&vs->sasl.conn); |
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vs->sasl.conn = NULL;
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goto authabort;
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} |
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if (serveroutlen > SASL_DATA_MAX_LEN) {
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VNC_DEBUG("sasl step reply data too long %d\n",
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serveroutlen); |
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sasl_dispose(&vs->sasl.conn); |
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vs->sasl.conn = NULL;
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goto authabort;
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} |
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VNC_DEBUG("SASL return data %d bytes, nil; %d\n",
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serveroutlen, serverout ? 0 : 1); |
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if (serveroutlen) {
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vnc_write_u32(vs, serveroutlen + 1);
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vnc_write(vs, serverout, serveroutlen + 1);
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} else {
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vnc_write_u32(vs, 0);
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} |
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/* Whether auth is complete */
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vnc_write_u8(vs, err == SASL_CONTINUE ? 0 : 1); |
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if (err == SASL_CONTINUE) {
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VNC_DEBUG("%s", "Authentication must continue\n"); |
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/* Wait for step length */
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vnc_read_when(vs, protocol_client_auth_sasl_step_len, 4);
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} else {
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if (!vnc_auth_sasl_check_ssf(vs)) {
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VNC_DEBUG("Authentication rejected for weak SSF %d\n", vs->csock);
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goto authreject;
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} |
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/* Check username whitelist ACL */
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if (vnc_auth_sasl_check_access(vs) < 0) { |
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VNC_DEBUG("Authentication rejected for ACL %d\n", vs->csock);
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goto authreject;
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} |
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VNC_DEBUG("Authentication successful %d\n", vs->csock);
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vnc_write_u32(vs, 0); /* Accept auth */ |
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/*
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* Delay writing in SSF encoded mode until pending output
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* buffer is written
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*/
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if (vs->sasl.runSSF)
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vs->sasl.waitWriteSSF = vs->output.offset; |
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start_client_init(vs); |
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} |
275 |
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return 0; |
277 |
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authreject:
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vnc_write_u32(vs, 1); /* Reject auth */ |
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vnc_write_u32(vs, sizeof("Authentication failed")); |
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vnc_write(vs, "Authentication failed", sizeof("Authentication failed")); |
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vnc_flush(vs); |
283 |
vnc_client_error(vs); |
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return -1; |
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authabort:
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vnc_client_error(vs); |
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return -1; |
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} |
290 |
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static int protocol_client_auth_sasl_step_len(VncState *vs, uint8_t *data, size_t len) |
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{ |
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uint32_t steplen = read_u32(data, 0);
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VNC_DEBUG("Got client step len %d\n", steplen);
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if (steplen > SASL_DATA_MAX_LEN) {
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VNC_DEBUG("Too much SASL data %d\n", steplen);
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vnc_client_error(vs); |
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return -1; |
299 |
} |
300 |
|
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if (steplen == 0) |
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return protocol_client_auth_sasl_step(vs, NULL, 0); |
303 |
else
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vnc_read_when(vs, protocol_client_auth_sasl_step, steplen); |
305 |
return 0; |
306 |
} |
307 |
|
308 |
/*
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309 |
* Start Msg
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310 |
*
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311 |
* Input from client:
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312 |
*
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* u32 clientin-length
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* u8-array clientin-string
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315 |
*
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* Output to client:
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317 |
*
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318 |
* u32 serverout-length
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* u8-array serverout-strin
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* u8 continue
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*/
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322 |
|
323 |
#define SASL_DATA_MAX_LEN (1024 * 1024) |
324 |
|
325 |
static int protocol_client_auth_sasl_start(VncState *vs, uint8_t *data, size_t len) |
326 |
{ |
327 |
uint32_t datalen = len; |
328 |
const char *serverout; |
329 |
unsigned int serveroutlen; |
330 |
int err;
|
331 |
char *clientdata = NULL; |
332 |
|
333 |
/* NB, distinction of NULL vs "" is *critical* in SASL */
|
334 |
if (datalen) {
|
335 |
clientdata = (char*)data;
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336 |
clientdata[datalen-1] = '\0'; /* Should be on wire, but make sure */ |
337 |
datalen--; /* Don't count NULL byte when passing to _start() */
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338 |
} |
339 |
|
340 |
VNC_DEBUG("Start SASL auth with mechanism %s. Data %p (%d bytes)\n",
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vs->sasl.mechlist, clientdata, datalen); |
342 |
err = sasl_server_start(vs->sasl.conn, |
343 |
vs->sasl.mechlist, |
344 |
clientdata, |
345 |
datalen, |
346 |
&serverout, |
347 |
&serveroutlen); |
348 |
if (err != SASL_OK &&
|
349 |
err != SASL_CONTINUE) { |
350 |
VNC_DEBUG("sasl start failed %d (%s)\n",
|
351 |
err, sasl_errdetail(vs->sasl.conn)); |
352 |
sasl_dispose(&vs->sasl.conn); |
353 |
vs->sasl.conn = NULL;
|
354 |
goto authabort;
|
355 |
} |
356 |
if (serveroutlen > SASL_DATA_MAX_LEN) {
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357 |
VNC_DEBUG("sasl start reply data too long %d\n",
|
358 |
serveroutlen); |
359 |
sasl_dispose(&vs->sasl.conn); |
360 |
vs->sasl.conn = NULL;
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361 |
goto authabort;
|
362 |
} |
363 |
|
364 |
VNC_DEBUG("SASL return data %d bytes, nil; %d\n",
|
365 |
serveroutlen, serverout ? 0 : 1); |
366 |
|
367 |
if (serveroutlen) {
|
368 |
vnc_write_u32(vs, serveroutlen + 1);
|
369 |
vnc_write(vs, serverout, serveroutlen + 1);
|
370 |
} else {
|
371 |
vnc_write_u32(vs, 0);
|
372 |
} |
373 |
|
374 |
/* Whether auth is complete */
|
375 |
vnc_write_u8(vs, err == SASL_CONTINUE ? 0 : 1); |
376 |
|
377 |
if (err == SASL_CONTINUE) {
|
378 |
VNC_DEBUG("%s", "Authentication must continue\n"); |
379 |
/* Wait for step length */
|
380 |
vnc_read_when(vs, protocol_client_auth_sasl_step_len, 4);
|
381 |
} else {
|
382 |
if (!vnc_auth_sasl_check_ssf(vs)) {
|
383 |
VNC_DEBUG("Authentication rejected for weak SSF %d\n", vs->csock);
|
384 |
goto authreject;
|
385 |
} |
386 |
|
387 |
/* Check username whitelist ACL */
|
388 |
if (vnc_auth_sasl_check_access(vs) < 0) { |
389 |
VNC_DEBUG("Authentication rejected for ACL %d\n", vs->csock);
|
390 |
goto authreject;
|
391 |
} |
392 |
|
393 |
VNC_DEBUG("Authentication successful %d\n", vs->csock);
|
394 |
vnc_write_u32(vs, 0); /* Accept auth */ |
395 |
start_client_init(vs); |
396 |
} |
397 |
|
398 |
return 0; |
399 |
|
400 |
authreject:
|
401 |
vnc_write_u32(vs, 1); /* Reject auth */ |
402 |
vnc_write_u32(vs, sizeof("Authentication failed")); |
403 |
vnc_write(vs, "Authentication failed", sizeof("Authentication failed")); |
404 |
vnc_flush(vs); |
405 |
vnc_client_error(vs); |
406 |
return -1; |
407 |
|
408 |
authabort:
|
409 |
vnc_client_error(vs); |
410 |
return -1; |
411 |
} |
412 |
|
413 |
static int protocol_client_auth_sasl_start_len(VncState *vs, uint8_t *data, size_t len) |
414 |
{ |
415 |
uint32_t startlen = read_u32(data, 0);
|
416 |
VNC_DEBUG("Got client start len %d\n", startlen);
|
417 |
if (startlen > SASL_DATA_MAX_LEN) {
|
418 |
VNC_DEBUG("Too much SASL data %d\n", startlen);
|
419 |
vnc_client_error(vs); |
420 |
return -1; |
421 |
} |
422 |
|
423 |
if (startlen == 0) |
424 |
return protocol_client_auth_sasl_start(vs, NULL, 0); |
425 |
|
426 |
vnc_read_when(vs, protocol_client_auth_sasl_start, startlen); |
427 |
return 0; |
428 |
} |
429 |
|
430 |
static int protocol_client_auth_sasl_mechname(VncState *vs, uint8_t *data, size_t len) |
431 |
{ |
432 |
char *mechname = malloc(len + 1); |
433 |
if (!mechname) {
|
434 |
VNC_DEBUG("Out of memory reading mechname\n");
|
435 |
vnc_client_error(vs); |
436 |
} |
437 |
strncpy(mechname, (char*)data, len);
|
438 |
mechname[len] = '\0';
|
439 |
VNC_DEBUG("Got client mechname '%s' check against '%s'\n",
|
440 |
mechname, vs->sasl.mechlist); |
441 |
|
442 |
if (strncmp(vs->sasl.mechlist, mechname, len) == 0) { |
443 |
if (vs->sasl.mechlist[len] != '\0' && |
444 |
vs->sasl.mechlist[len] != ',') {
|
445 |
VNC_DEBUG("One %d", vs->sasl.mechlist[len]);
|
446 |
vnc_client_error(vs); |
447 |
return -1; |
448 |
} |
449 |
} else {
|
450 |
char *offset = strstr(vs->sasl.mechlist, mechname);
|
451 |
VNC_DEBUG("Two %p\n", offset);
|
452 |
if (!offset) {
|
453 |
vnc_client_error(vs); |
454 |
return -1; |
455 |
} |
456 |
VNC_DEBUG("Two '%s'\n", offset);
|
457 |
if (offset[-1] != ',' || |
458 |
(offset[len] != '\0'&&
|
459 |
offset[len] != ',')) {
|
460 |
vnc_client_error(vs); |
461 |
return -1; |
462 |
} |
463 |
} |
464 |
|
465 |
free(vs->sasl.mechlist); |
466 |
vs->sasl.mechlist = mechname; |
467 |
|
468 |
VNC_DEBUG("Validated mechname '%s'\n", mechname);
|
469 |
vnc_read_when(vs, protocol_client_auth_sasl_start_len, 4);
|
470 |
return 0; |
471 |
} |
472 |
|
473 |
static int protocol_client_auth_sasl_mechname_len(VncState *vs, uint8_t *data, size_t len) |
474 |
{ |
475 |
uint32_t mechlen = read_u32(data, 0);
|
476 |
VNC_DEBUG("Got client mechname len %d\n", mechlen);
|
477 |
if (mechlen > 100) { |
478 |
VNC_DEBUG("Too long SASL mechname data %d\n", mechlen);
|
479 |
vnc_client_error(vs); |
480 |
return -1; |
481 |
} |
482 |
if (mechlen < 1) { |
483 |
VNC_DEBUG("Too short SASL mechname %d\n", mechlen);
|
484 |
vnc_client_error(vs); |
485 |
return -1; |
486 |
} |
487 |
vnc_read_when(vs, protocol_client_auth_sasl_mechname,mechlen); |
488 |
return 0; |
489 |
} |
490 |
|
491 |
#define USES_X509_AUTH(vs) \
|
492 |
((vs)->subauth == VNC_AUTH_VENCRYPT_X509NONE || \ |
493 |
(vs)->subauth == VNC_AUTH_VENCRYPT_X509VNC || \ |
494 |
(vs)->subauth == VNC_AUTH_VENCRYPT_X509PLAIN || \ |
495 |
(vs)->subauth == VNC_AUTH_VENCRYPT_X509SASL) |
496 |
|
497 |
|
498 |
void start_auth_sasl(VncState *vs)
|
499 |
{ |
500 |
const char *mechlist = NULL; |
501 |
sasl_security_properties_t secprops; |
502 |
int err;
|
503 |
char *localAddr, *remoteAddr;
|
504 |
int mechlistlen;
|
505 |
|
506 |
VNC_DEBUG("Initialize SASL auth %d\n", vs->csock);
|
507 |
|
508 |
/* Get local & remote client addresses in form IPADDR;PORT */
|
509 |
if (!(localAddr = vnc_socket_local_addr("%s;%s", vs->csock))) |
510 |
goto authabort;
|
511 |
|
512 |
if (!(remoteAddr = vnc_socket_remote_addr("%s;%s", vs->csock))) { |
513 |
free(localAddr); |
514 |
goto authabort;
|
515 |
} |
516 |
|
517 |
err = sasl_server_new("vnc",
|
518 |
NULL, /* FQDN - just delegates to gethostname */ |
519 |
NULL, /* User realm */ |
520 |
localAddr, |
521 |
remoteAddr, |
522 |
NULL, /* Callbacks, not needed */ |
523 |
SASL_SUCCESS_DATA, |
524 |
&vs->sasl.conn); |
525 |
free(localAddr); |
526 |
free(remoteAddr); |
527 |
localAddr = remoteAddr = NULL;
|
528 |
|
529 |
if (err != SASL_OK) {
|
530 |
VNC_DEBUG("sasl context setup failed %d (%s)",
|
531 |
err, sasl_errstring(err, NULL, NULL)); |
532 |
vs->sasl.conn = NULL;
|
533 |
goto authabort;
|
534 |
} |
535 |
|
536 |
#ifdef CONFIG_VNC_TLS
|
537 |
/* Inform SASL that we've got an external SSF layer from TLS/x509 */
|
538 |
if (vs->vd->auth == VNC_AUTH_VENCRYPT &&
|
539 |
vs->vd->subauth == VNC_AUTH_VENCRYPT_X509SASL) { |
540 |
gnutls_cipher_algorithm_t cipher; |
541 |
sasl_ssf_t ssf; |
542 |
|
543 |
cipher = gnutls_cipher_get(vs->tls.session); |
544 |
if (!(ssf = (sasl_ssf_t)gnutls_cipher_get_key_size(cipher))) {
|
545 |
VNC_DEBUG("%s", "cannot TLS get cipher size\n"); |
546 |
sasl_dispose(&vs->sasl.conn); |
547 |
vs->sasl.conn = NULL;
|
548 |
goto authabort;
|
549 |
} |
550 |
ssf *= 8; /* tls key size is bytes, sasl wants bits */ |
551 |
|
552 |
err = sasl_setprop(vs->sasl.conn, SASL_SSF_EXTERNAL, &ssf); |
553 |
if (err != SASL_OK) {
|
554 |
VNC_DEBUG("cannot set SASL external SSF %d (%s)\n",
|
555 |
err, sasl_errstring(err, NULL, NULL)); |
556 |
sasl_dispose(&vs->sasl.conn); |
557 |
vs->sasl.conn = NULL;
|
558 |
goto authabort;
|
559 |
} |
560 |
} else
|
561 |
#endif /* CONFIG_VNC_TLS */ |
562 |
vs->sasl.wantSSF = 1;
|
563 |
|
564 |
memset (&secprops, 0, sizeof secprops); |
565 |
/* Inform SASL that we've got an external SSF layer from TLS */
|
566 |
if (strncmp(vs->vd->display, "unix:", 5) == 0 |
567 |
#ifdef CONFIG_VNC_TLS
|
568 |
/* Disable SSF, if using TLS+x509+SASL only. TLS without x509
|
569 |
is not sufficiently strong */
|
570 |
|| (vs->vd->auth == VNC_AUTH_VENCRYPT && |
571 |
vs->vd->subauth == VNC_AUTH_VENCRYPT_X509SASL) |
572 |
#endif /* CONFIG_VNC_TLS */ |
573 |
) { |
574 |
/* If we've got TLS or UNIX domain sock, we don't care about SSF */
|
575 |
secprops.min_ssf = 0;
|
576 |
secprops.max_ssf = 0;
|
577 |
secprops.maxbufsize = 8192;
|
578 |
secprops.security_flags = 0;
|
579 |
} else {
|
580 |
/* Plain TCP, better get an SSF layer */
|
581 |
secprops.min_ssf = 56; /* Good enough to require kerberos */ |
582 |
secprops.max_ssf = 100000; /* Arbitrary big number */ |
583 |
secprops.maxbufsize = 8192;
|
584 |
/* Forbid any anonymous or trivially crackable auth */
|
585 |
secprops.security_flags = |
586 |
SASL_SEC_NOANONYMOUS | SASL_SEC_NOPLAINTEXT; |
587 |
} |
588 |
|
589 |
err = sasl_setprop(vs->sasl.conn, SASL_SEC_PROPS, &secprops); |
590 |
if (err != SASL_OK) {
|
591 |
VNC_DEBUG("cannot set SASL security props %d (%s)\n",
|
592 |
err, sasl_errstring(err, NULL, NULL)); |
593 |
sasl_dispose(&vs->sasl.conn); |
594 |
vs->sasl.conn = NULL;
|
595 |
goto authabort;
|
596 |
} |
597 |
|
598 |
err = sasl_listmech(vs->sasl.conn, |
599 |
NULL, /* Don't need to set user */ |
600 |
"", /* Prefix */ |
601 |
",", /* Separator */ |
602 |
"", /* Suffix */ |
603 |
&mechlist, |
604 |
NULL,
|
605 |
NULL);
|
606 |
if (err != SASL_OK) {
|
607 |
VNC_DEBUG("cannot list SASL mechanisms %d (%s)\n",
|
608 |
err, sasl_errdetail(vs->sasl.conn)); |
609 |
sasl_dispose(&vs->sasl.conn); |
610 |
vs->sasl.conn = NULL;
|
611 |
goto authabort;
|
612 |
} |
613 |
VNC_DEBUG("Available mechanisms for client: '%s'\n", mechlist);
|
614 |
|
615 |
if (!(vs->sasl.mechlist = strdup(mechlist))) {
|
616 |
VNC_DEBUG("Out of memory");
|
617 |
sasl_dispose(&vs->sasl.conn); |
618 |
vs->sasl.conn = NULL;
|
619 |
goto authabort;
|
620 |
} |
621 |
mechlistlen = strlen(mechlist); |
622 |
vnc_write_u32(vs, mechlistlen); |
623 |
vnc_write(vs, mechlist, mechlistlen); |
624 |
vnc_flush(vs); |
625 |
|
626 |
VNC_DEBUG("Wait for client mechname length\n");
|
627 |
vnc_read_when(vs, protocol_client_auth_sasl_mechname_len, 4);
|
628 |
|
629 |
return;
|
630 |
|
631 |
authabort:
|
632 |
vnc_client_error(vs); |
633 |
return;
|
634 |
} |
635 |
|
636 |
|