int FileRepConnServer_ReceiveMessageType( FileRepConsumerProcIndex_e *fileRepMessageType) { char messageType; int status = STATUS_OK; messageType = pq_getbyte(); switch (messageType) { case '1': *fileRepMessageType = FileRepMessageTypeXLog; break; case '2': *fileRepMessageType = FileRepMessageTypeAO01; break; case '3': *fileRepMessageType = FileRepMessageTypeWriter; break; case 'S': *fileRepMessageType = FileRepMessageTypeShutdown; break; case EOF: ereport(WARNING, (errcode_for_socket_access(), errmsg("receive EOF on connection: %m"))); status = STATUS_ERROR; break; case 'X': /* Close Message(sent by PQfinish()) */ /* * Client closed connection. Client does not wait for response. */ ereport(WARNING, (errcode_for_socket_access(), errmsg("receive close on connection: %m"))); status = STATUS_ERROR; break; default: ereport(WARNING, (errcode_for_socket_access(), errmsg("receive unexpected message type on connection: %m"))); status = STATUS_ERROR; break; } return status; }
/* These blow 2 wrapper functions is required for backward * compatibility beyond the PostgreSQL commit: * Be more careful to not lose sync in the FE/BE protocol.*/ static int Wrappered_pq_getbyte(void) { #if (PG_VERSION_NUM >= 90401) \ || ((PG_VERSION_NUM >= 90306) && (PG_VERSION_NUM < 90400)) \ || ((PG_VERSION_NUM >= 90210) && (PG_VERSION_NUM < 90300)) \ || ((PG_VERSION_NUM >= 90115) && (PG_VERSION_NUM < 90200)) \ || ((PG_VERSION_NUM >= 90019) && (PG_VERSION_NUM < 90100)) pq_startmsgread(); #endif return pq_getbyte(); }
/* * Execute commands from walreceiver, until we enter streaming mode. */ static void WalSndHandshake(void) { StringInfoData input_message; bool replication_started = false; initStringInfo(&input_message); while (!replication_started) { int firstchar; WalSndSetState(WALSNDSTATE_STARTUP); set_ps_display("idle", false); /* Wait for a command to arrive */ firstchar = pq_getbyte(); /* * Emergency bailout if postmaster has died. This is to avoid the * necessity for manual cleanup of all postmaster children. */ if (!PostmasterIsAlive()) exit(1); /* * Check for any other interesting events that happened while we * slept. */ if (got_SIGHUP) { got_SIGHUP = false; ProcessConfigFile(PGC_SIGHUP); } if (firstchar != EOF) { /* * Read the message contents. This is expected to be done without * blocking because we've been able to get message type code. */ if (pq_getmessage(&input_message, 0)) firstchar = EOF; /* suitable message already logged */ } /* Handle the very limited subset of commands expected in this phase */ switch (firstchar) { case 'Q': /* Query message */ { const char *query_string; query_string = pq_getmsgstring(&input_message); pq_getmsgend(&input_message); if (HandleReplicationCommand(query_string)) replication_started = true; } break; case 'X': /* standby is closing the connection */ proc_exit(0); case EOF: /* standby disconnected unexpectedly */ ereport(COMMERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("unexpected EOF on standby connection"))); proc_exit(0); default: ereport(FATAL, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("invalid standby handshake message type %d", firstchar))); } } }
/* * Collect password response packet from frontend. * * Returns NULL if couldn't get password, else palloc'd string. */ static char * recv_password_packet(Port *port) { StringInfoData buf; if (PG_PROTOCOL_MAJOR(port->proto) >= 3) { /* Expect 'p' message type */ int mtype; mtype = pq_getbyte(); if (mtype != 'p') { /* * If the client just disconnects without offering a password, * don't make a log entry. This is legal per protocol spec * and in fact commonly done by psql, so complaining just * clutters the log. */ if (mtype != EOF) ereport(COMMERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("expected password response, got message type %d", mtype))); return NULL; /* EOF or bad message type */ } } else { /* For pre-3.0 clients, avoid log entry if they just disconnect */ if (pq_peekbyte() == EOF) return NULL; /* EOF */ } initStringInfo(&buf); if (pq_getmessage(&buf, 1000)) /* receive password */ { /* EOF - pq_getmessage already logged a suitable message */ pfree(buf.data); return NULL; } /* * Apply sanity check: password packet length should agree with length * of contained string. Note it is safe to use strlen here because * StringInfo is guaranteed to have an appended '\0'. */ if (strlen(buf.data) + 1 != buf.len) ereport(COMMERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("invalid password packet size"))); /* Do not echo password to logs, for security. */ ereport(DEBUG5, (errmsg("received password packet"))); /* * Return the received string. Note we do not attempt to do any * character-set conversion on it; since we don't yet know the * client's encoding, there wouldn't be much point. */ return buf.data; }
/* * Execute commands from walreceiver, until we enter streaming mode. */ static void WalSndHandshake(void) { StringInfoData input_message; bool replication_started = false; initStringInfo(&input_message); while (!replication_started) { int firstchar; /* Wait for a command to arrive */ firstchar = pq_getbyte(); /* * Emergency bailout if postmaster has died. This is to avoid the * necessity for manual cleanup of all postmaster children. */ if (!PostmasterIsAlive(true)) exit(1); /* * Check for any other interesting events that happened while we * slept. */ if (got_SIGHUP) { got_SIGHUP = false; ProcessConfigFile(PGC_SIGHUP); } if (firstchar != EOF) { /* * Read the message contents. This is expected to be done without * blocking because we've been able to get message type code. */ if (pq_getmessage(&input_message, 0)) firstchar = EOF; /* suitable message already logged */ } /* Handle the very limited subset of commands expected in this phase */ switch (firstchar) { case 'Q': /* Query message */ { const char *query_string; XLogRecPtr recptr; query_string = pq_getmsgstring(&input_message); pq_getmsgend(&input_message); if (strcmp(query_string, "IDENTIFY_SYSTEM") == 0) { StringInfoData buf; char sysid[32]; char tli[11]; /* * Reply with a result set with one row, two columns. * First col is system ID, and second is timeline ID */ snprintf(sysid, sizeof(sysid), UINT64_FORMAT, GetSystemIdentifier()); snprintf(tli, sizeof(tli), "%u", ThisTimeLineID); /* Send a RowDescription message */ pq_beginmessage(&buf, 'T'); pq_sendint(&buf, 2, 2); /* 2 fields */ /* first field */ pq_sendstring(&buf, "systemid"); /* col name */ pq_sendint(&buf, 0, 4); /* table oid */ pq_sendint(&buf, 0, 2); /* attnum */ pq_sendint(&buf, TEXTOID, 4); /* type oid */ pq_sendint(&buf, -1, 2); /* typlen */ pq_sendint(&buf, 0, 4); /* typmod */ pq_sendint(&buf, 0, 2); /* format code */ /* second field */ pq_sendstring(&buf, "timeline"); /* col name */ pq_sendint(&buf, 0, 4); /* table oid */ pq_sendint(&buf, 0, 2); /* attnum */ pq_sendint(&buf, INT4OID, 4); /* type oid */ pq_sendint(&buf, 4, 2); /* typlen */ pq_sendint(&buf, 0, 4); /* typmod */ pq_sendint(&buf, 0, 2); /* format code */ pq_endmessage(&buf); /* Send a DataRow message */ pq_beginmessage(&buf, 'D'); pq_sendint(&buf, 2, 2); /* # of columns */ pq_sendint(&buf, strlen(sysid), 4); /* col1 len */ pq_sendbytes(&buf, (char *) &sysid, strlen(sysid)); pq_sendint(&buf, strlen(tli), 4); /* col2 len */ pq_sendbytes(&buf, (char *) tli, strlen(tli)); pq_endmessage(&buf); /* Send CommandComplete and ReadyForQuery messages */ EndCommand("SELECT", DestRemote); ReadyForQuery(DestRemote); /* ReadyForQuery did pq_flush for us */ } else if (sscanf(query_string, "START_REPLICATION %X/%X", &recptr.xlogid, &recptr.xrecoff) == 2) { StringInfoData buf; /* * Check that we're logging enough information in the * WAL for log-shipping. * * NOTE: This only checks the current value of * wal_level. Even if the current setting is not * 'minimal', there can be old WAL in the pg_xlog * directory that was created with 'minimal'. So this * is not bulletproof, the purpose is just to give a * user-friendly error message that hints how to * configure the system correctly. */ if (wal_level == WAL_LEVEL_MINIMAL) ereport(FATAL, (errcode(ERRCODE_CANNOT_CONNECT_NOW), errmsg("standby connections not allowed because wal_level=minimal"))); /* Send a CopyOutResponse message, and start streaming */ pq_beginmessage(&buf, 'H'); pq_sendbyte(&buf, 0); pq_sendint(&buf, 0, 2); pq_endmessage(&buf); pq_flush(); /* * Initialize position to the received one, then the * xlog records begin to be shipped from that position */ sentPtr = recptr; /* break out of the loop */ replication_started = true; } else { ereport(FATAL, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("invalid standby query string: %s", query_string))); } break; } case 'X': /* standby is closing the connection */ proc_exit(0); case EOF: /* standby disconnected unexpectedly */ ereport(COMMERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("unexpected EOF on standby connection"))); proc_exit(0); default: ereport(FATAL, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("invalid standby handshake message type %d", firstchar))); } } }
static int pg_SSPI_recvauth(Port *port) { int mtype; StringInfoData buf; SECURITY_STATUS r; CredHandle sspicred; CtxtHandle *sspictx = NULL, newctx; TimeStamp expiry; ULONG contextattr; SecBufferDesc inbuf; SecBufferDesc outbuf; SecBuffer OutBuffers[1]; SecBuffer InBuffers[1]; HANDLE token; TOKEN_USER *tokenuser; DWORD retlen; char accountname[MAXPGPATH]; char domainname[MAXPGPATH]; DWORD accountnamesize = sizeof(accountname); DWORD domainnamesize = sizeof(domainname); SID_NAME_USE accountnameuse; HMODULE secur32; QUERY_SECURITY_CONTEXT_TOKEN_FN _QuerySecurityContextToken; /* * SSPI auth is not supported for protocol versions before 3, because it * relies on the overall message length word to determine the SSPI payload * size in AuthenticationGSSContinue and PasswordMessage messages. * (This is, in fact, a design error in our SSPI support, because protocol * messages are supposed to be parsable without relying on the length * word; but it's not worth changing it now.) */ if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3) ereport(FATAL, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("SSPI is not supported in protocol version 2"))); /* * Acquire a handle to the server credentials. */ r = AcquireCredentialsHandle(NULL, "negotiate", SECPKG_CRED_INBOUND, NULL, NULL, NULL, NULL, &sspicred, &expiry); if (r != SEC_E_OK) pg_SSPI_error(ERROR, gettext_noop("could not acquire SSPI credentials handle"), r); /* * Loop through SSPI message exchange. This exchange can consist of * multiple messags sent in both directions. First message is always from * the client. All messages from client to server are password packets * (type 'p'). */ do { mtype = pq_getbyte(); if (mtype != 'p') { /* Only log error if client didn't disconnect. */ if (mtype != EOF) ereport(COMMERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("expected SSPI response, got message type %d", mtype))); return STATUS_ERROR; } /* Get the actual SSPI token */ initStringInfo(&buf); if (pq_getmessage(&buf, 2000)) { /* EOF - pq_getmessage already logged error */ pfree(buf.data); return STATUS_ERROR; } /* Map to SSPI style buffer */ inbuf.ulVersion = SECBUFFER_VERSION; inbuf.cBuffers = 1; inbuf.pBuffers = InBuffers; InBuffers[0].pvBuffer = buf.data; InBuffers[0].cbBuffer = buf.len; InBuffers[0].BufferType = SECBUFFER_TOKEN; /* Prepare output buffer */ OutBuffers[0].pvBuffer = NULL; OutBuffers[0].BufferType = SECBUFFER_TOKEN; OutBuffers[0].cbBuffer = 0; outbuf.cBuffers = 1; outbuf.pBuffers = OutBuffers; outbuf.ulVersion = SECBUFFER_VERSION; elog(DEBUG4, "Processing received SSPI token of length %u", (unsigned int) buf.len); r = AcceptSecurityContext(&sspicred, sspictx, &inbuf, ASC_REQ_ALLOCATE_MEMORY, SECURITY_NETWORK_DREP, &newctx, &outbuf, &contextattr, NULL); /* input buffer no longer used */ pfree(buf.data); if (outbuf.cBuffers > 0 && outbuf.pBuffers[0].cbBuffer > 0) { /* * Negotiation generated data to be sent to the client. */ elog(DEBUG4, "sending SSPI response token of length %u", (unsigned int) outbuf.pBuffers[0].cbBuffer); port->gss->outbuf.length = outbuf.pBuffers[0].cbBuffer; port->gss->outbuf.value = outbuf.pBuffers[0].pvBuffer; sendAuthRequest(port, AUTH_REQ_GSS_CONT); FreeContextBuffer(outbuf.pBuffers[0].pvBuffer); } if (r != SEC_E_OK && r != SEC_I_CONTINUE_NEEDED) { if (sspictx != NULL) { DeleteSecurityContext(sspictx); free(sspictx); } FreeCredentialsHandle(&sspicred); pg_SSPI_error(ERROR, gettext_noop("could not accept SSPI security context"), r); } if (sspictx == NULL) { sspictx = malloc(sizeof(CtxtHandle)); if (sspictx == NULL) ereport(ERROR, (errmsg("out of memory"))); memcpy(sspictx, &newctx, sizeof(CtxtHandle)); } if (r == SEC_I_CONTINUE_NEEDED) elog(DEBUG4, "SSPI continue needed"); } while (r == SEC_I_CONTINUE_NEEDED); /* * Release service principal credentials */ FreeCredentialsHandle(&sspicred); /* * SEC_E_OK indicates that authentication is now complete. * * Get the name of the user that authenticated, and compare it to the pg * username that was specified for the connection. * * MingW is missing the export for QuerySecurityContextToken in the * secur32 library, so we have to load it dynamically. */ secur32 = LoadLibrary("SECUR32.DLL"); if (secur32 == NULL) ereport(ERROR, (errmsg_internal("could not load secur32.dll: %d", (int) GetLastError()))); _QuerySecurityContextToken = (QUERY_SECURITY_CONTEXT_TOKEN_FN) GetProcAddress(secur32, "QuerySecurityContextToken"); if (_QuerySecurityContextToken == NULL) { FreeLibrary(secur32); ereport(ERROR, (errmsg_internal("could not locate QuerySecurityContextToken in secur32.dll: %d", (int) GetLastError()))); } r = (_QuerySecurityContextToken) (sspictx, &token); if (r != SEC_E_OK) { FreeLibrary(secur32); pg_SSPI_error(ERROR, gettext_noop("could not get security token from context"), r); } FreeLibrary(secur32); /* * No longer need the security context, everything from here on uses the * token instead. */ DeleteSecurityContext(sspictx); free(sspictx); if (!GetTokenInformation(token, TokenUser, NULL, 0, &retlen) && GetLastError() != 122) ereport(ERROR, (errmsg_internal("could not get token user size: error code %d", (int) GetLastError()))); tokenuser = malloc(retlen); if (tokenuser == NULL) ereport(ERROR, (errmsg("out of memory"))); if (!GetTokenInformation(token, TokenUser, tokenuser, retlen, &retlen)) ereport(ERROR, (errmsg_internal("could not get user token: error code %d", (int) GetLastError()))); if (!LookupAccountSid(NULL, tokenuser->User.Sid, accountname, &accountnamesize, domainname, &domainnamesize, &accountnameuse)) ereport(ERROR, (errmsg_internal("could not lookup acconut sid: error code %d", (int) GetLastError()))); free(tokenuser); /* * Compare realm/domain if requested. In SSPI, always compare case * insensitive. */ if (pg_krb_realm && strlen(pg_krb_realm)) { if (pg_strcasecmp(pg_krb_realm, domainname)) { elog(DEBUG2, "SSPI domain (%s) and configured domain (%s) don't match", domainname, pg_krb_realm); return STATUS_ERROR; } } /* * We have the username (without domain/realm) in accountname, compare to * the supplied value. In SSPI, always compare case insensitive. */ if (pg_strcasecmp(port->user_name, accountname)) { /* GSS name and PGUSER are not equivalent */ elog(DEBUG2, "provided username (%s) and SSPI username (%s) don't match", port->user_name, accountname); return STATUS_ERROR; } return STATUS_OK; }
static int pg_GSS_recvauth(Port *port) { OM_uint32 maj_stat, min_stat, lmin_s, gflags; int mtype; int ret; StringInfoData buf; gss_buffer_desc gbuf; /* * GSS auth is not supported for protocol versions before 3, because it * relies on the overall message length word to determine the GSS payload * size in AuthenticationGSSContinue and PasswordMessage messages. * (This is, in fact, a design error in our GSS support, because protocol * messages are supposed to be parsable without relying on the length * word; but it's not worth changing it now.) */ if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3) ereport(FATAL, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("GSSAPI is not supported in protocol version 2"))); if (pg_krb_server_keyfile && strlen(pg_krb_server_keyfile) > 0) { /* * Set default Kerberos keytab file for the Krb5 mechanism. * * setenv("KRB5_KTNAME", pg_krb_server_keyfile, 0); except setenv() * not always available. */ if (getenv("KRB5_KTNAME") == NULL) { size_t kt_len = strlen(pg_krb_server_keyfile) + 14; char *kt_path = malloc(kt_len); if (!kt_path) { ereport(LOG, (errcode(ERRCODE_OUT_OF_MEMORY), errmsg("out of memory"))); return STATUS_ERROR; } snprintf(kt_path, kt_len, "KRB5_KTNAME=%s", pg_krb_server_keyfile); putenv(kt_path); } } /* * We accept any service principal that's present in our keytab. This * increases interoperability between kerberos implementations that see * for example case sensitivity differently, while not really opening up * any vector of attack. */ port->gss->cred = GSS_C_NO_CREDENTIAL; /* * Initialize sequence with an empty context */ port->gss->ctx = GSS_C_NO_CONTEXT; /* * Loop through GSSAPI message exchange. This exchange can consist of * multiple messags sent in both directions. First message is always from * the client. All messages from client to server are password packets * (type 'p'). */ do { mtype = pq_getbyte(); if (mtype != 'p') { /* Only log error if client didn't disconnect. */ if (mtype != EOF) ereport(COMMERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("expected GSS response, got message type %d", mtype))); return STATUS_ERROR; } /* Get the actual GSS token */ initStringInfo(&buf); if (pq_getmessage(&buf, 2000)) { /* EOF - pq_getmessage already logged error */ pfree(buf.data); return STATUS_ERROR; } /* Map to GSSAPI style buffer */ gbuf.length = buf.len; gbuf.value = buf.data; elog(DEBUG4, "Processing received GSS token of length %u", (unsigned int) gbuf.length); maj_stat = gss_accept_sec_context( &min_stat, &port->gss->ctx, port->gss->cred, &gbuf, GSS_C_NO_CHANNEL_BINDINGS, &port->gss->name, NULL, &port->gss->outbuf, &gflags, NULL, NULL); /* gbuf no longer used */ pfree(buf.data); elog(DEBUG5, "gss_accept_sec_context major: %d, " "minor: %d, outlen: %u, outflags: %x", maj_stat, min_stat, (unsigned int) port->gss->outbuf.length, gflags); if (port->gss->outbuf.length != 0) { /* * Negotiation generated data to be sent to the client. */ OM_uint32 lmin_s; elog(DEBUG4, "sending GSS response token of length %u", (unsigned int) port->gss->outbuf.length); sendAuthRequest(port, AUTH_REQ_GSS_CONT); gss_release_buffer(&lmin_s, &port->gss->outbuf); } if (maj_stat != GSS_S_COMPLETE && maj_stat != GSS_S_CONTINUE_NEEDED) { OM_uint32 lmin_s; gss_delete_sec_context(&lmin_s, &port->gss->ctx, GSS_C_NO_BUFFER); pg_GSS_error(ERROR, gettext_noop("accepting GSS security context failed"), maj_stat, min_stat); } if (maj_stat == GSS_S_CONTINUE_NEEDED) elog(DEBUG4, "GSS continue needed"); } while (maj_stat == GSS_S_CONTINUE_NEEDED); if (port->gss->cred != GSS_C_NO_CREDENTIAL) { /* * Release service principal credentials */ gss_release_cred(&min_stat, &port->gss->cred); } /* * GSS_S_COMPLETE indicates that authentication is now complete. * * Get the name of the user that authenticated, and compare it to the pg * username that was specified for the connection. */ maj_stat = gss_display_name(&min_stat, port->gss->name, &gbuf, NULL); if (maj_stat != GSS_S_COMPLETE) pg_GSS_error(ERROR, gettext_noop("retrieving GSS user name failed"), maj_stat, min_stat); /* * Split the username at the realm separator */ if (strchr(gbuf.value, '@')) { char *cp = strchr(gbuf.value, '@'); *cp = '\0'; cp++; if (pg_krb_realm != NULL && strlen(pg_krb_realm)) { /* * Match the realm part of the name first */ if (pg_krb_caseins_users) ret = pg_strcasecmp(pg_krb_realm, cp); else ret = strcmp(pg_krb_realm, cp); if (ret) { /* GSS realm does not match */ elog(DEBUG2, "GSSAPI realm (%s) and configured realm (%s) don't match", cp, pg_krb_realm); gss_release_buffer(&lmin_s, &gbuf); return STATUS_ERROR; } } } else if (pg_krb_realm && strlen(pg_krb_realm)) { elog(DEBUG2, "GSSAPI did not return realm but realm matching was requested"); gss_release_buffer(&lmin_s, &gbuf); return STATUS_ERROR; } if (pg_krb_caseins_users) ret = pg_strcasecmp(port->user_name, gbuf.value); else ret = strcmp(port->user_name, gbuf.value); if (ret) { /* GSS name and PGUSER are not equivalent */ elog(DEBUG2, "provided username (%s) and GSSAPI username (%s) don't match", port->user_name, (char *) gbuf.value); gss_release_buffer(&lmin_s, &gbuf); return STATUS_ERROR; } gss_release_buffer(&lmin_s, &gbuf); return STATUS_OK; }