diff options
| -rw-r--r-- | src/interfaces/libpq/fe-connect.c | 13 | ||||
| -rw-r--r-- | src/interfaces/libpq/fe-protocol3.c | 91 | ||||
| -rw-r--r-- | src/interfaces/libpq/libpq-int.h | 2 |
3 files changed, 71 insertions, 35 deletions
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c index d5051f5e820..0256753bd3e 100644 --- a/src/interfaces/libpq/fe-connect.c +++ b/src/interfaces/libpq/fe-connect.c @@ -667,6 +667,7 @@ pqDropServerData(PGconn *conn) /* Reset assorted other per-connection state */ conn->last_sqlstate[0] = '\0'; + conn->pversion_negotiated = false; conn->auth_req_received = false; conn->client_finished_auth = false; conn->password_needed = false; @@ -4084,16 +4085,24 @@ keep_going: /* We will come back to here until there is CONNECTION_FAILED(); } + /* Handle NegotiateProtocolVersion */ else if (beresp == PqMsg_NegotiateProtocolVersion) { + if (conn->pversion_negotiated) + { + libpq_append_conn_error(conn, "received duplicate protocol negotiation message"); + goto error_return; + } if (pqGetNegotiateProtocolVersion3(conn)) { - libpq_append_conn_error(conn, "received invalid protocol negotiation message"); + /* pqGetNegotiateProtocolVersion3 set error already */ goto error_return; } + conn->pversion_negotiated = true; + /* OK, we read the message; mark data consumed */ pqParseDone(conn, conn->inCursor); - goto error_return; + goto keep_going; } /* It is an authentication request. */ diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c index 95dd456f076..43e3519e4bd 100644 --- a/src/interfaces/libpq/fe-protocol3.c +++ b/src/interfaces/libpq/fe-protocol3.c @@ -870,6 +870,7 @@ advance_and_error: /* * Attempt to read an Error or Notice response message. * This is possible in several places, so we break it out as a subroutine. + * * Entry: 'E' or 'N' message type and length have already been consumed. * Exit: returns 0 if successfully consumed message. * returns EOF if not enough data. @@ -1399,64 +1400,87 @@ reportErrorPosition(PQExpBuffer msg, const char *query, int loc, int encoding) /* - * Attempt to read a NegotiateProtocolVersion message. + * Attempt to read a NegotiateProtocolVersion message. Sets conn->pversion + * to the version that's negotiated by the server. + * * Entry: 'v' message type and length have already been consumed. * Exit: returns 0 if successfully consumed message. - * returns EOF if not enough data. + * returns 1 on failure. The error message is filled in. */ int pqGetNegotiateProtocolVersion3(PGconn *conn) { - int tmp; - ProtocolVersion their_version; + int their_version; int num; - PQExpBufferData buf; - if (pqGetInt(&tmp, 4, conn) != 0) - return EOF; - their_version = tmp; + if (pqGetInt(&their_version, 4, conn) != 0) + goto eof; if (pqGetInt(&num, 4, conn) != 0) - return EOF; + goto eof; - initPQExpBuffer(&buf); - for (int i = 0; i < num; i++) + /* Check the protocol version */ + if (their_version > conn->pversion) { - if (pqGets(&conn->workBuffer, conn)) - { - termPQExpBuffer(&buf); - return EOF; - } - if (buf.len > 0) - appendPQExpBufferChar(&buf, ' '); - appendPQExpBufferStr(&buf, conn->workBuffer.data); + libpq_append_conn_error(conn, "received invalid protocol negotiation message: server requested downgrade to a higher-numbered version"); + goto failure; + } + + if (their_version < PG_PROTOCOL(3, 0)) + { + libpq_append_conn_error(conn, "received invalid protocol negotiation message: server requested downgrade to pre-3.0 protocol version"); + goto failure; } - if (their_version < conn->pversion) - libpq_append_conn_error(conn, "protocol version not supported by server: client uses %u.%u, server supports up to %u.%u", - PG_PROTOCOL_MAJOR(conn->pversion), PG_PROTOCOL_MINOR(conn->pversion), - PG_PROTOCOL_MAJOR(their_version), PG_PROTOCOL_MINOR(their_version)); - if (num > 0) + if (num < 0) { - appendPQExpBuffer(&conn->errorMessage, - libpq_ngettext("protocol extension not supported by server: %s", - "protocol extensions not supported by server: %s", num), - buf.data); - appendPQExpBufferChar(&conn->errorMessage, '\n'); + libpq_append_conn_error(conn, "received invalid protocol negotiation message: server reported negative number of unsupported parameters"); + goto failure; + } + + if (their_version == conn->pversion && num == 0) + { + libpq_append_conn_error(conn, "received invalid protocol negotiation message: server negotiated but asks for no changes"); + goto failure; } - /* neither -- server shouldn't have sent it */ - if (!(their_version < conn->pversion) && !(num > 0)) - libpq_append_conn_error(conn, "invalid %s message", "NegotiateProtocolVersion"); + /* the version is acceptable */ + conn->pversion = their_version; + + /* + * We don't currently request any protocol extensions, so we don't expect + * the server to reply with any either. + */ + for (int i = 0; i < num; i++) + { + if (pqGets(&conn->workBuffer, conn)) + { + goto eof; + } + if (strncmp(conn->workBuffer.data, "_pq_.", 5) != 0) + { + libpq_append_conn_error(conn, "received invalid protocol negotiation message: server reported unsupported parameter name without a _pq_. prefix (\"%s\")", conn->workBuffer.data); + goto failure; + } + libpq_append_conn_error(conn, "received invalid protocol negotiation message: server reported an unsupported parameter that was not requested (\"%s\")", conn->workBuffer.data); + goto failure; + } - termPQExpBuffer(&buf); return 0; + +eof: + libpq_append_conn_error(conn, "received invalid protocol negotation message: message too short"); +failure: + conn->asyncStatus = PGASYNC_READY; + pqSaveErrorResult(conn); + return 1; } /* * Attempt to read a ParameterStatus message. * This is possible in several places, so we break it out as a subroutine. + * * Entry: 'S' message type and length have already been consumed. * Exit: returns 0 if successfully consumed message. * returns EOF if not enough data. @@ -1486,6 +1510,7 @@ getParameterStatus(PGconn *conn) /* * Attempt to read a Notify response message. * This is possible in several places, so we break it out as a subroutine. + * * Entry: 'A' message type and length have already been consumed. * Exit: returns 0 if successfully consumed Notify message. * returns EOF if not enough data. diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h index ade5ad82f07..d9f2e9ad743 100644 --- a/src/interfaces/libpq/libpq-int.h +++ b/src/interfaces/libpq/libpq-int.h @@ -496,6 +496,8 @@ struct pg_conn SockAddr raddr; /* Remote address */ ProtocolVersion pversion; /* FE/BE protocol version in use */ int sversion; /* server version, e.g. 70401 for 7.4.1 */ + bool pversion_negotiated; /* true if NegotiateProtocolVersion + * was received */ bool auth_req_received; /* true if any type of auth req received */ bool password_needed; /* true if server demanded a password */ bool gssapi_used; /* true if authenticated via gssapi */ |