From 01d0fc2aac8764aab94d421103530c7f6a11a213 Mon Sep 17 00:00:00 2001 From: Jelte Fennema-Nio Date: Wed, 14 Aug 2024 18:25:16 +0200 Subject: [PATCH v17 6/8] Bump protocol version to 3.2 In preparation of new additions to the protocol in a follow up commit this bumps the minor protocol version number. Instead of bumping the version number to 3.1, which would be the next minor version, we skip that one and bump straight to 3.2. The reason for this is that many PgBouncer releases have, due to an off-by-one bug, reported 3.1 as supported[1]. These versions would interpret 3.1 as equivalent to 3.0. So if we would now add extra messages to the 3.1 protocol, clients would succeed to connect to PgBouncer, but would then cause connection failures when sending such new messages. So instead of bumping to 3.1, we bump the protocol version to 3.2, for which these buggy PgBouncer releases will correctly close the connection at the startup packet. It's a bit strange to skip a version number due to a bug in a third-party application, but PgBouncer is used widely enough that it seems worth it to not cause user confusion when connecting to recent versions of it. Especially since skipping a single minor version number in the protocol versioning doesn't really cost us anything. So, while this is not the most theoretically sound decission, it is the most pragmatic one. [1]: https://github.com/pgbouncer/pgbouncer/pull/1007 --- doc/src/sgml/libpq.sgml | 8 +- src/include/libpq/pqcomm.h | 3 +- src/interfaces/libpq/fe-connect.c | 9 ++ src/interfaces/libpq/fe-protocol3.c | 8 +- .../modules/libpq_pipeline/libpq_pipeline.c | 110 +++++++++++++++--- 5 files changed, 117 insertions(+), 21 deletions(-) diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml index d80a21041d2..ed5bdaa280c 100644 --- a/doc/src/sgml/libpq.sgml +++ b/doc/src/sgml/libpq.sgml @@ -2388,7 +2388,8 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname The current supported values are - 3.0 + 3.0, + 3.2, and latest. The latest value is equivalent to the latest protocol version that is supported by the used libpq version, which currently is 3.2, but this will @@ -2415,10 +2416,11 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname The current supported values are - 3.0 + 3.0, + 3.2, and latest. The latest value is equivalent to the latest protocol version that is supported by the used - libpq version, which currently is 3.0, but this will + libpq version, which currently is 3.2, but this will change in future libpq releases. diff --git a/src/include/libpq/pqcomm.h b/src/include/libpq/pqcomm.h index 46b37e0e4eb..0aceb7147c7 100644 --- a/src/include/libpq/pqcomm.h +++ b/src/include/libpq/pqcomm.h @@ -91,11 +91,10 @@ is_unixsock_path(const char *path) /* * The earliest and latest frontend/backend protocol version supported. - * (Only protocol version 3 is currently supported) */ #define PG_PROTOCOL_EARLIEST PG_PROTOCOL(3,0) -#define PG_PROTOCOL_LATEST PG_PROTOCOL(3,0) +#define PG_PROTOCOL_LATEST PG_PROTOCOL(3,2) typedef uint32 ProtocolVersion; /* FE/BE protocol version number */ diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c index 60a4a6aaff3..c3936e08e83 100644 --- a/src/interfaces/libpq/fe-connect.c +++ b/src/interfaces/libpq/fe-connect.c @@ -8180,6 +8180,15 @@ pqParseProtocolVersion(const char *value, ProtocolVersion *result, PGconn *conn, return true; } + if (strcmp(value, "3.1") == 0) + { + conn->status = CONNECTION_BAD; + libpq_append_conn_error(conn, "invalid %s value: \"%s\"", + context, + value); + return false; + } + major = strtol(value, &end, 10); if (*end != '.') { diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c index 2ed1b21c046..c3efd0e39d5 100644 --- a/src/interfaces/libpq/fe-protocol3.c +++ b/src/interfaces/libpq/fe-protocol3.c @@ -1427,7 +1427,13 @@ pqGetNegotiateProtocolVersion3(PGconn *conn) libpq_append_conn_error(conn, "received invalid protocol negotiation message: server requests downgrade to pre-3.0 protocol version"); goto failure; } - + + if (their_version == PG_PROTOCOL(3, 1)) + { + libpq_append_conn_error(conn, "received invalid protocol negotiation message: server requests downgrade to 3.1 protocol version"); + goto failure; + } + if (num < 0) { libpq_append_conn_error(conn, "received invalid protocol negotiation message: server reported negative number of unsupported parameters"); diff --git a/src/test/modules/libpq_pipeline/libpq_pipeline.c b/src/test/modules/libpq_pipeline/libpq_pipeline.c index 5f840323a32..9df3f6276d3 100644 --- a/src/test/modules/libpq_pipeline/libpq_pipeline.c +++ b/src/test/modules/libpq_pipeline/libpq_pipeline.c @@ -198,24 +198,15 @@ send_cancellable_query_impl(int line, PGconn *conn, PGconn *monitorConn) } /* - * Create a new connection with the same conninfo as the given one. + * Fills keywords and vals, with the same options as the ones in the opts + * linked-list. Returns the length of the filled in list. */ -static PGconn * -copy_connection(PGconn *conn) +static +int +copy_connection_options(PQconninfoOption *opts, const char **keywords, const char **vals) { - PGconn *copyConn; - PQconninfoOption *opts = PQconninfo(conn); - const char **keywords; - const char **vals; - int nopts = 1; int i = 0; - for (PQconninfoOption *opt = opts; opt->keyword != NULL; ++opt) - nopts++; - - keywords = pg_malloc(sizeof(char *) * nopts); - vals = pg_malloc(sizeof(char *) * nopts); - for (PQconninfoOption *opt = opts; opt->keyword != NULL; ++opt) { if (opt->val) @@ -225,8 +216,28 @@ copy_connection(PGconn *conn) i++; } } - keywords[i] = vals[i] = NULL; + return i; +} + +/* + * Create a new connection with the same conninfo as the given one. + */ +static PGconn * +copy_connection(PGconn *conn) +{ + const char **keywords; + const char **vals; + PGconn *copyConn; + PQconninfoOption *opts = PQconninfo(conn); + int nopts = 1; /* 1 for the NULL terminator */ + for (PQconninfoOption *opt = opts; opt->keyword != NULL; ++opt) + nopts++; + + keywords = pg_malloc0(sizeof(char *) * nopts); + vals = pg_malloc0(sizeof(char *) * nopts); + + copy_connection_options(opts, keywords, vals); copyConn = PQconnectdbParams(keywords, vals, false); if (PQstatus(copyConn) != CONNECTION_OK) @@ -1406,6 +1417,72 @@ test_prepared(PGconn *conn) fprintf(stderr, "ok\n"); } +static void +test_protocol_version(PGconn *conn) +{ + const char **keywords; + const char **vals; + int nopts = 2; /* NULL terminator + max_protocol_version */ + PQconninfoOption *opts = PQconninfo(conn); + int protocol_version; + int max_protocol_version_index; + + for (PQconninfoOption *opt = opts; opt->keyword != NULL; ++opt) + nopts++; + + keywords = pg_malloc0(sizeof(char *) * nopts); + vals = pg_malloc0(sizeof(char *) * nopts); + + max_protocol_version_index = copy_connection_options(opts, keywords, vals); + + keywords[max_protocol_version_index] = "max_protocol_version"; + vals[max_protocol_version_index] = "3.0"; + + conn = PQconnectdbParams(keywords, vals, false); + + if (PQstatus(conn) != CONNECTION_OK) + pg_fatal("Connection to database failed: %s", + PQerrorMessage(conn)); + + protocol_version = PQfullProtocolVersion(conn); + if (protocol_version != 30000) + pg_fatal("expected 30000, got %d", protocol_version); + + PQfinish(conn); + + vals[max_protocol_version_index] = "3.1"; + conn = PQconnectdbParams(keywords, vals, false); + + if (PQstatus(conn) != CONNECTION_BAD) + pg_fatal("Connecting with max_protocol_version 3.1 should have failed."); + + PQfinish(conn); + + vals[max_protocol_version_index] = "3.2"; + conn = PQconnectdbParams(keywords, vals, false); + + if (PQstatus(conn) != CONNECTION_OK) + pg_fatal("Connection to database failed: %s", + PQerrorMessage(conn)); + + protocol_version = PQfullProtocolVersion(conn); + if (protocol_version != 30002) + pg_fatal("expected 30002, got %d", protocol_version); + PQfinish(conn); + + vals[max_protocol_version_index] = "latest"; + conn = PQconnectdbParams(keywords, vals, false); + + if (PQstatus(conn) != CONNECTION_OK) + pg_fatal("Connection to database failed: %s", + PQerrorMessage(conn)); + + protocol_version = PQfullProtocolVersion(conn); + if (protocol_version != 30002) + pg_fatal("expected 30002, got %d", protocol_version); + PQfinish(conn); +} + /* Notice processor: print notices, and count how many we got */ static void notice_processor(void *arg, const char *message) @@ -2154,6 +2231,7 @@ print_test_list(void) printf("pipeline_idle\n"); printf("pipelined_insert\n"); printf("prepared\n"); + printf("protocol_version\n"); printf("simple_pipeline\n"); printf("singlerow\n"); printf("transaction\n"); @@ -2273,6 +2351,8 @@ main(int argc, char **argv) test_pipelined_insert(conn, numrows); else if (strcmp(testname, "prepared") == 0) test_prepared(conn); + else if (strcmp(testname, "protocol_version") == 0) + test_protocol_version(conn); else if (strcmp(testname, "simple_pipeline") == 0) test_simple_pipeline(conn); else if (strcmp(testname, "singlerow") == 0) -- 2.43.0