libpq: Trace responses to SSLRequest and GSSENCRequest

Since these are single bytes instead of v2 or v3 messages they need
custom tracing logic.  These "messages" don't even have official names
in the protocol specification, so I (Jelte) called them SSLResponse and
GSSENCResponse here.

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/CAGECzQSoPHtZ4xe0raJ6FYSEiPPS+YWXBhOGo+Y1YecLgknF3g@mail.gmail.com

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 360d9a454760ffe2a1fed1b3451586ef6bc08e71..a5055271ae37eba1478a1153febeea1c72855511 100644 (file)
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -3493,11 +3493,17 @@ keep_going:                                             /* We will come back to here until there is
                                        }
                                        if (SSLok == 'S')
                                        {
+                                               if (conn->Pfdebug)
+                                                       pqTraceOutputCharResponse(conn, "SSLResponse",
+                                                                                                         SSLok);
                                                /* mark byte consumed */
                                                conn->inStart = conn->inCursor;
                                        }
                                        else if (SSLok == 'N')
                                        {
+                                               if (conn->Pfdebug)
+                                                       pqTraceOutputCharResponse(conn, "SSLResponse",
+                                                                                                         SSLok);
                                                /* mark byte consumed */
                                                conn->inStart = conn->inCursor;
 
@@ -3635,6 +3641,10 @@ keep_going:                                              /* We will come back to here until there is
 
                                        if (gss_ok == 'N')
                                        {
+                                               if (conn->Pfdebug)
+                                                       pqTraceOutputCharResponse(conn, "GSSENCResponse",
+                                                                                                         gss_ok);
+
                                                /*
                                                 * The connection is still valid, so if it's OK to
                                                 * continue without GSS, we can proceed using this
@@ -3648,6 +3658,10 @@ keep_going:                                              /* We will come back to here until there is
                                                                                                gss_ok);
                                                goto error_return;
                                        }
+
+                                       if (conn->Pfdebug)
+                                               pqTraceOutputCharResponse(conn, "GSSENCResponse",
+                                                                                                 gss_ok);
                                }
 
                                /* Begin or continue GSSAPI negotiation */

diff --git a/src/interfaces/libpq/fe-trace.c b/src/interfaces/libpq/fe-trace.c
index 367b322b992f0ef34de45e1f47ebe43e59b6f547..3527b9f0f5dff6f8587791cb15c34c2c9ccffb8c 100644 (file)
--- a/src/interfaces/libpq/fe-trace.c
+++ b/src/interfaces/libpq/fe-trace.c
@@ -840,3 +840,23 @@ pqTraceOutputNoTypeByteMessage(PGconn *conn, const char *message)
 
        fputc('\n', conn->Pfdebug);
 }
+
+/*
+ * Trace a single-byte backend response received for a known request
+ * type the frontend previously sent.  Only useful for the simplest of
+ * FE/BE interaction workflows such as SSL/GSS encryption requests.
+ */
+void
+pqTraceOutputCharResponse(PGconn *conn, const char *responseType,
+                                                 char response)
+{
+       if ((conn->traceFlags & PQTRACE_SUPPRESS_TIMESTAMPS) == 0)
+       {
+               char            timestr[128];
+
+               pqTraceFormatTimestamp(timestr, sizeof(timestr));
+               fprintf(conn->Pfdebug, "%s\t", timestr);
+       }
+
+       fprintf(conn->Pfdebug, "B\t1\t%s\t %c\n", responseType, response);
+}

diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
index 03e4da40ba1d98c79c77e3c7fc2e29aaf29c3f48..d97b595c97f3f41a62fce9a01fe8796fc1a6a35e 100644 (file)
--- a/src/interfaces/libpq/libpq-int.h
+++ b/src/interfaces/libpq/libpq-int.h
@@ -889,6 +889,8 @@ extern ssize_t pg_GSS_read(PGconn *conn, void *ptr, size_t len);
 extern void pqTraceOutputMessage(PGconn *conn, const char *message,
                                                                 bool toServer);
 extern void pqTraceOutputNoTypeByteMessage(PGconn *conn, const char *message);
+extern void pqTraceOutputCharResponse(PGconn *conn, const char *responseType,
+                                                                         char response);
 
 /* === miscellaneous macros === */