Add more columns to pg_stat_ssl

Add columns client_serial and issuer_dn to pg_stat_ssl.  These allow
uniquely identifying the client certificate.

Rename the existing column clientdn to client_dn, to make the naming
more consistent and easier to read.

Discussion: https://www.postgresql.org/message-id/flat/398754d8-6bb5-c5cf-e7b8-22e5f0983caf@2ndquadrant.com/

10 files changed, 84 insertions, 23 deletions

diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index f4d9e9daf71..3e229c693c4 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -782,7 +782,9 @@ CREATE VIEW pg_stat_ssl AS
             S.sslcipher AS cipher,
             S.sslbits AS bits,
             S.sslcompression AS compression,
-            S.sslclientdn AS clientdn
+            S.ssl_client_dn AS client_dn,
+            S.ssl_client_serial AS client_serial,
+            S.ssl_issuer_dn AS issuer_dn
     FROM pg_stat_get_activity(NULL) AS S;
 
 CREATE VIEW pg_replication_slots AS
diff --git a/src/backend/libpq/be-secure-openssl.c b/src/backend/libpq/be-secure-openssl.c
index 789a9754090..a2779543ec1 100644
--- a/src/backend/libpq/be-secure-openssl.c
+++ b/src/backend/libpq/be-secure-openssl.c
@@ -1109,7 +1109,7 @@ be_tls_get_cipher(Port *port)
 }
 
 void
-be_tls_get_peerdn_name(Port *port, char *ptr, size_t len)
+be_tls_get_peer_subject_name(Port *port, char *ptr, size_t len)
 {
 	if (port->peer)
 		strlcpy(ptr, X509_NAME_to_cstring(X509_get_subject_name(port->peer)), len);
@@ -1117,6 +1117,35 @@ be_tls_get_peerdn_name(Port *port, char *ptr, size_t len)
 		ptr[0] = '\0';
 }
 
+void
+be_tls_get_peer_issuer_name(Port *port, char *ptr, size_t len)
+{
+	if (port->peer)
+		strlcpy(ptr, X509_NAME_to_cstring(X509_get_issuer_name(port->peer)), len);
+	else
+		ptr[0] = '\0';
+}
+
+void
+be_tls_get_peer_serial(Port *port, char *ptr, size_t len)
+{
+	if (port->peer)
+	{
+		ASN1_INTEGER *serial;
+		BIGNUM	   *b;
+		char	   *decimal;
+
+		serial = X509_get_serialNumber(port->peer);
+		b = ASN1_INTEGER_to_BN(serial, NULL);
+		decimal = BN_bn2dec(b);
+		BN_free(b);
+		strlcpy(ptr, decimal, len);
+		OPENSSL_free(decimal);
+	}
+	else
+		ptr[0] = '\0';
+}
+
 #ifdef HAVE_X509_GET_SIGNATURE_NID
 char *
 be_tls_get_certificate_hash(Port *port, size_t *len)
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 3b9e86f7702..81c64992518 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -2906,7 +2906,9 @@ pgstat_bestart(void)
 		beentry->st_sslstatus->ssl_compression = be_tls_get_compression(MyProcPort);
 		strlcpy(beentry->st_sslstatus->ssl_version, be_tls_get_version(MyProcPort), NAMEDATALEN);
 		strlcpy(beentry->st_sslstatus->ssl_cipher, be_tls_get_cipher(MyProcPort), NAMEDATALEN);
-		be_tls_get_peerdn_name(MyProcPort, beentry->st_sslstatus->ssl_clientdn, NAMEDATALEN);
+		be_tls_get_peer_subject_name(MyProcPort, beentry->st_sslstatus->ssl_client_dn, NAMEDATALEN);
+		be_tls_get_peer_serial(MyProcPort, beentry->st_sslstatus->ssl_client_serial, NAMEDATALEN);
+		be_tls_get_peer_issuer_name(MyProcPort, beentry->st_sslstatus->ssl_issuer_dn, NAMEDATALEN);
 	}
 	else
 	{
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 20ebcfbcdf6..b6ba856ebe6 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -541,7 +541,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	24
+#define PG_STAT_GET_ACTIVITY_COLS	26
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -652,15 +652,29 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			values[20] = CStringGetTextDatum(beentry->st_sslstatus->ssl_cipher);
 			values[21] = Int32GetDatum(beentry->st_sslstatus->ssl_bits);
 			values[22] = BoolGetDatum(beentry->st_sslstatus->ssl_compression);
-			if (beentry->st_sslstatus->ssl_clientdn[0])
-				values[23] = CStringGetTextDatum(beentry->st_sslstatus->ssl_clientdn);
+
+			if (beentry->st_sslstatus->ssl_client_dn[0])
+				values[23] = CStringGetTextDatum(beentry->st_sslstatus->ssl_client_dn);
 			else
 				nulls[23] = true;
+
+			if (beentry->st_sslstatus->ssl_client_serial[0])
+				values[24] = DirectFunctionCall3(numeric_in,
+												 CStringGetDatum(beentry->st_sslstatus->ssl_client_serial),
+												 ObjectIdGetDatum(InvalidOid),
+												 Int32GetDatum(-1));
+			else
+				nulls[24] = true;
+
+			if (beentry->st_sslstatus->ssl_issuer_dn[0])
+				values[25] = CStringGetTextDatum(beentry->st_sslstatus->ssl_issuer_dn);
+			else
+				nulls[25] = true;
 		}
 		else
 		{
 			values[18] = BoolGetDatum(false);	/* ssl */
-			nulls[19] = nulls[20] = nulls[21] = nulls[22] = nulls[23] = true;
+			nulls[19] = nulls[20] = nulls[21] = nulls[22] = nulls[23] = nulls[24] = nulls[25] = true;
 		}
 
 		/* Values only available to role member or pg_read_all_stats */
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 7b3c88a1385..ea9a5ade23d 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	201901041
+#define CATALOG_VERSION_NO	201902011
 
 #endif
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 3ecc2e12c3f..b8de13f03b9 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5058,9 +5058,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,bool,text}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,sslcompression,sslclientdn}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,bool,text,numeric,text}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,sslcompression,ssl_client_dn,ssl_client_serial,ssl_issuer_dn}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/libpq/libpq-be.h b/src/include/libpq/libpq-be.h
index 7570649b5b4..248055f10b4 100644
--- a/src/include/libpq/libpq-be.h
+++ b/src/include/libpq/libpq-be.h
@@ -258,7 +258,9 @@ extern int	be_tls_get_cipher_bits(Port *port);
 extern bool be_tls_get_compression(Port *port);
 extern const char *be_tls_get_version(Port *port);
 extern const char *be_tls_get_cipher(Port *port);
-extern void be_tls_get_peerdn_name(Port *port, char *ptr, size_t len);
+extern void be_tls_get_peer_subject_name(Port *port, char *ptr, size_t len);
+extern void be_tls_get_peer_issuer_name(Port *port, char *ptr, size_t len);
+extern void be_tls_get_peer_serial(Port *port, char *ptr, size_t len);
 
 /*
  * Get the server certificate hash for SCRAM channel binding type
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 0ce79489dad..88a75fb798e 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -950,15 +950,25 @@ typedef enum ProgressCommandType
  *
  * For each backend, we keep the SSL status in a separate struct, that
  * is only filled in if SSL is enabled.
+ *
+ * All char arrays must be null-terminated.
  */
 typedef struct PgBackendSSLStatus
 {
 	/* Information about SSL connection */
 	int			ssl_bits;
 	bool		ssl_compression;
-	char		ssl_version[NAMEDATALEN];	/* MUST be null-terminated */
-	char		ssl_cipher[NAMEDATALEN];	/* MUST be null-terminated */
-	char		ssl_clientdn[NAMEDATALEN];	/* MUST be null-terminated */
+	char		ssl_version[NAMEDATALEN];
+	char		ssl_cipher[NAMEDATALEN];
+	char		ssl_client_dn[NAMEDATALEN];
+
+	/*
+	 * serial number is max "20 octets" per RFC 5280, so this size should be
+	 * fine
+	 */
+	char		ssl_client_serial[NAMEDATALEN];
+
+	char		ssl_issuer_dn[NAMEDATALEN];
 } PgBackendSSLStatus;
 
 
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index e384cd22798..2c8e21baa7e 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1731,7 +1731,7 @@ pg_stat_activity| SELECT s.datid,
     s.backend_xmin,
     s.query,
     s.backend_type
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, sslcompression, ssl_client_dn, ssl_client_serial, ssl_issuer_dn)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1863,7 +1863,7 @@ pg_stat_replication| SELECT s.pid,
     w.sync_priority,
     w.sync_state,
     w.reply_time
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, sslcompression, ssl_client_dn, ssl_client_serial, ssl_issuer_dn)
      JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_ssl| SELECT s.pid,
@@ -1872,8 +1872,10 @@ pg_stat_ssl| SELECT s.pid,
     s.sslcipher AS cipher,
     s.sslbits AS bits,
     s.sslcompression AS compression,
-    s.sslclientdn AS clientdn
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn);
+    s.ssl_client_dn AS client_dn,
+    s.ssl_client_serial AS client_serial,
+    s.ssl_issuer_dn AS issuer_dn
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, sslcompression, ssl_client_dn, ssl_client_serial, ssl_issuer_dn);
 pg_stat_subscription| SELECT su.oid AS subid,
     su.subname,
     st.pid,
diff --git a/src/test/ssl/t/001_ssltests.pl b/src/test/ssl/t/001_ssltests.pl
index bbddb8e2b76..915007805e5 100644
--- a/src/test/ssl/t/001_ssltests.pl
+++ b/src/test/ssl/t/001_ssltests.pl
@@ -315,8 +315,8 @@ command_like([
 	'-d', "$common_connstr sslrootcert=invalid",
 	'-c', "SELECT * FROM pg_stat_ssl WHERE pid = pg_backend_pid()"
 			 ],
-			 qr{^pid,ssl,version,cipher,bits,compression,clientdn\n
-				^\d+,t,TLSv[\d.]+,[\w-]+,\d+,f,_null_$}mx,
+			 qr{^pid,ssl,version,cipher,bits,compression,client_dn,client_serial,issuer_dn\n
+				^\d+,t,TLSv[\d.]+,[\w-]+,\d+,f,_null_,_null_,_null_$}mx,
 			 'pg_stat_ssl view without client certificate');
 
 ### Server-side tests.
@@ -347,8 +347,8 @@ command_like([
 	'-d', "$common_connstr user=ssltestuser sslcert=ssl/client.crt sslkey=ssl/client_tmp.key",
 	'-c', "SELECT * FROM pg_stat_ssl WHERE pid = pg_backend_pid()"
 			 ],
-			 qr{^pid,ssl,version,cipher,bits,compression,clientdn\n
-				^\d+,t,TLSv[\d.]+,[\w-]+,\d+,f,/CN=ssltestuser$}mx,
+			 qr{^pid,ssl,version,cipher,bits,compression,client_dn,client_serial,issuer_dn\n
+				^\d+,t,TLSv[\d.]+,[\w-]+,\d+,f,/CN=ssltestuser,1,\Q/CN=Test CA for PostgreSQL SSL regression test client certs\E$}mx,
 			 'pg_stat_ssl with client certificate');
 
 # client key with wrong permissions