1 files changed, 365 insertions, 0 deletions
diff --git a/src/backend/libpq/be-secure.c b/src/backend/libpq/be-secure.c
new file mode 100644
index 00000000000..6501882e4a5
--- /dev/null
+++ b/src/backend/libpq/be-secure.c
@@ -0,0 +1,365 @@
+/*-------------------------------------------------------------------------
+ *
+ * be-connect.c
+ *	  functions related to setting up a secure connection to the frontend.
+ *	  Secure connections are expected to provide confidentiality,
+ *	  message integrity and endpoint authentication.
+ *
+ *
+ * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  $Header: /cvsroot/pgsql/src/backend/libpq/be-secure.c,v 1.1 2002/06/14 04:23:17 momjian Exp $
+ *	  
+ * PATCH LEVEL
+ *	  milestone 1: fix basic coding errors
+ *	  [*] existing SSL code pulled out of existing files.
+ *	  [*] SSL_get_error() after SSL_read() and SSL_write(),
+ *	      SSL_shutdown(), default to TLSv1.
+ *	
+ *	  milestone 2: provide endpoint authentication (server)
+ *	  [*] client verifies server cert
+ *	  [*] client verifies server hostname
+ *
+ *	  milestone 3: improve confidentially, support perfect forward secrecy
+ *	  [ ] use 'random' file, read from '/dev/urandom?'
+ *	  [ ] emphermal DH keys, default values
+ *	  [ ] periodic renegotiation
+ *
+ *	  milestone 4: provide endpoint authentication (client)
+ *	  [ ] server verifies client certificates
+ *
+ *	  milestone 5: provide informational callbacks
+ *	  [ ] provide informational callbacks
+ *
+ *	  other changes
+ *	  [ ] tcp-wrappers
+ *	  [ ] more informative psql
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include <sys/types.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <ctype.h>
+
+#include "libpq/libpq.h"
+#include "libpq/pqsignal.h"
+#include "miscadmin.h"
+
+#ifdef WIN32
+#include "win32.h"
+#else
+#include <sys/socket.h>
+#include <unistd.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#ifdef HAVE_NETINET_TCP_H
+#include <netinet/tcp.h>
+#endif
+#include <arpa/inet.h>
+#endif
+
+
+#ifndef HAVE_STRDUP
+#include "strdup.h"
+#endif
+
+#ifdef USE_SSL
+#include <openssl/ssl.h>
+#include <openssl/e_os.h>
+#endif
+
+extern void ExitPostmaster(int);
+extern void postmaster_error(const char *fmt,...);
+
+int secure_initialize(void);
+void secure_destroy(void);
+int secure_open_server(Port *);
+void secure_close(Port *);
+ssize_t secure_read(Port *, void *ptr, size_t len);
+ssize_t secure_write(Port *, const void *ptr, size_t len);
+
+#ifdef USE_SSL
+static int initialize_SSL(void);
+static void destroy_SSL(void);
+static int open_server_SSL(Port *);
+static void close_SSL(Port *);
+static const char *SSLerrmessage(void);
+#endif
+
+#ifdef USE_SSL
+static SSL_CTX *SSL_context = NULL;
+#endif
+
+/* ------------------------------------------------------------ */
+/*           Procedures common to all secure sessions           */
+/* ------------------------------------------------------------ */
+
+/*
+ *	Initialize global context
+ */
+int
+secure_initialize (void)
+{
+	int r = 0;
+
+#ifdef USE_SSL
+	r = initialize_SSL();
+#endif
+
+	return r;
+}
+
+/*
+ *	Destroy global context
+ */
+void
+secure_destroy (void)
+{
+#ifdef USE_SSL
+	destroy_SSL();
+#endif
+}
+
+/*
+ *	Attempt to negotiate secure session.
+ */
+int 
+secure_open_server (Port *port)
+{
+	int r = 0;
+
+#ifdef USE_SSL
+	r = open_server_SSL(port);
+#endif
+
+	return r;
+}
+
+/*
+ *	Close secure session.
+ */
+void
+secure_close (Port *port)
+{
+#ifdef USE_SSL
+	if (port->ssl)
+		close_SSL(port);
+#endif
+}
+
+/*
+ *	Read data from a secure connection.
+ */
+ssize_t
+secure_read (Port *port, void *ptr, size_t len)
+{
+	ssize_t n;
+
+#ifdef USE_SSL
+	if (port->ssl)
+	{
+		n = SSL_read(port->ssl, ptr, len);
+		switch (SSL_get_error(port->ssl, n))
+		{
+		case SSL_ERROR_NONE:
+			break;
+		case SSL_ERROR_WANT_READ:
+			break;
+		case SSL_ERROR_SYSCALL:
+			errno = get_last_socket_error();
+			elog(ERROR, "SSL SYSCALL error: %s", strerror(errno));
+			break;
+		case SSL_ERROR_SSL:
+			elog(ERROR, "SSL error: %s", SSLerrmessage());
+			/* fall through */
+		case SSL_ERROR_ZERO_RETURN:
+			secure_close(port);
+			errno = ECONNRESET;
+			n = -1;
+			break;
+		}
+	}
+	else
+#endif
+	n = recv(port->sock, ptr, len, 0);
+
+	return n;
+}
+
+/*
+ *	Write data to a secure connection.
+ */
+ssize_t
+secure_write (Port *port, const void *ptr, size_t len)
+{
+	ssize_t n;
+
+#ifndef WIN32
+	pqsigfunc oldsighandler = pqsignal(SIGPIPE, SIG_IGN);
+#endif
+
+#ifdef USE_SSL
+	if (port->ssl)
+	{
+		n = SSL_write(port->ssl, ptr, len);
+		switch (SSL_get_error(port->ssl, n))
+		{
+		case SSL_ERROR_NONE:
+			break;
+		case SSL_ERROR_WANT_WRITE:
+			break;
+		case SSL_ERROR_SYSCALL:
+			errno = get_last_socket_error();
+			elog(ERROR, "SSL SYSCALL error: %s", strerror(errno));
+			break;
+		case SSL_ERROR_SSL:
+			elog(ERROR, "SSL error: %s", SSLerrmessage());
+			/* fall through */
+		case SSL_ERROR_ZERO_RETURN:
+			secure_close(port);
+			errno = ECONNRESET;
+			n = -1;
+			break;
+		}
+	}
+	else
+#endif
+	n = send(port->sock, ptr, len, 0);
+
+#ifndef WIN32
+	pqsignal(SIGPIPE, oldsighandler);
+#endif
+
+	return n;
+}
+
+/* ------------------------------------------------------------ */
+/*                        SSL specific code                     */
+/* ------------------------------------------------------------ */
+#ifdef USE_SSL
+/*
+ *	Initialize global SSL context.
+ */
+static int
+initialize_SSL (void)
+{
+	char fnbuf[2048];
+
+	if (!SSL_context)
+	{
+		SSL_library_init();
+		SSL_load_error_strings();
+		SSL_context = SSL_CTX_new(TLSv1_method());
+		if (!SSL_context)
+		{
+			postmaster_error("failed to create SSL context: %s",
+							 SSLerrmessage());
+			ExitPostmaster(1);
+		}
+
+		/*
+		 *	Load and verify certificate and private key
+		 */
+		snprintf(fnbuf, sizeof(fnbuf), "%s/server.crt", DataDir);
+		if (!SSL_CTX_use_certificate_file(SSL_context, fnbuf, SSL_FILETYPE_PEM))
+		{
+			postmaster_error("failed to load server certificate (%s): %s",
+							 fnbuf, SSLerrmessage());
+			ExitPostmaster(1);
+		}
+		snprintf(fnbuf, sizeof(fnbuf), "%s/server.key", DataDir);
+		if (!SSL_CTX_use_PrivateKey_file(SSL_context, fnbuf, SSL_FILETYPE_PEM))
+		{
+			postmaster_error("failed to load private key file (%s): %s",
+							 fnbuf, SSLerrmessage());
+			ExitPostmaster(1);
+		}
+		if (!SSL_CTX_check_private_key(SSL_context))
+		{
+			postmaster_error("check of private key failed: %s",
+							 SSLerrmessage());
+			ExitPostmaster(1);
+		}
+	}
+
+	return 0;
+}
+
+/*
+ *	Destroy global SSL context.
+ */
+static void
+destroy_SSL (void)
+{
+	if (SSL_context)
+	{
+		SSL_CTX_free(SSL_context);
+		SSL_context = NULL;
+	}
+}
+
+/*
+ *	Attempt to negotiate SSL connection.
+ */
+static int
+open_server_SSL (Port *port)
+{
+	if (!(port->ssl = SSL_new(SSL_context)) ||
+		!SSL_set_fd(port->ssl, port->sock) ||
+		SSL_accept(port->ssl) <= 0)
+	{
+		elog(ERROR, "failed to initialize SSL connection: %s", SSLerrmessage());
+		close_SSL(port);
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ *	Close SSL connection.
+ */
+static void
+close_SSL (Port *port)
+{
+	if (port->ssl)
+	{
+		SSL_shutdown(port->ssl);
+		SSL_free(port->ssl);
+		port->ssl = NULL;
+	}
+}
+
+/*
+ * Obtain reason string for last SSL error
+ *
+ * Some caution is needed here since ERR_reason_error_string will
+ * return NULL if it doesn't recognize the error code.  We don't
+ * want to return NULL ever.
+ */
+static const char *
+SSLerrmessage(void)
+{
+	unsigned long	errcode;
+	const char	   *errreason;
+	static char		errbuf[32];
+
+	errcode = ERR_get_error();
+	if (errcode == 0)
+		return "No SSL error reported";
+	errreason = ERR_reason_error_string(errcode);
+	if (errreason != NULL)
+		return errreason;
+	snprintf(errbuf, sizeof(errbuf), "SSL error code %lu", errcode);
+	return errbuf;
+}
+
+#endif /* USE_SSL */