sshd: switch GSSAPI to sshbuf API; ok djm@

4 files changed, 86 insertions, 65 deletions

diff --git a/usr.bin/ssh/auth2-gss.c b/usr.bin/ssh/auth2-gss.c
index c9c11a130c9..789206ef2f2 100644
--- a/usr.bin/ssh/auth2-gss.c
+++ b/usr.bin/ssh/auth2-gss.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth2-gss.c,v 1.26 2017/06/24 06:34:38 djm Exp $ */
+/* $OpenBSD: auth2-gss.c,v 1.27 2018/07/09 21:37:55 markus Exp $ */
 
 /*
  * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
@@ -29,13 +29,14 @@
 #include <sys/types.h>
 
 #include "xmalloc.h"
-#include "key.h"
+#include "sshkey.h"
 #include "hostfile.h"
 #include "auth.h"
 #include "ssh2.h"
 #include "log.h"
 #include "dispatch.h"
-#include "buffer.h"
+#include "sshbuf.h"
+#include "ssherr.h"
 #include "servconf.h"
 #include "packet.h"
 #include "ssh-gss.h"
@@ -58,16 +59,18 @@ userauth_gssapi(struct ssh *ssh)
 	Authctxt *authctxt = ssh->authctxt;
 	gss_OID_desc goid = {0, NULL};
 	Gssctxt *ctxt = NULL;
-	int mechs;
-	int present;
+	int r, present;
+	u_int mechs;
 	OM_uint32 ms;
-	u_int len;
+	size_t len;
 	u_char *doid = NULL;
 
 	if (!authctxt->valid || authctxt->user == NULL)
 		return (0);
 
-	mechs = packet_get_int();
+	if ((r = sshpkt_get_u32(ssh, &mechs)) != 0)
+		fatal("%s: %s", __func__, ssh_err(r));
+
 	if (mechs == 0) {
 		debug("Mechanism negotiation is not supported");
 		return (0);
@@ -79,7 +82,8 @@ userauth_gssapi(struct ssh *ssh)
 		free(doid);
 
 		present = 0;
-		doid = packet_get_string(&len);
+		if ((r = sshpkt_get_string(ssh, &doid, &len)) != 0)
+			fatal("%s: %s", __func__, ssh_err(r));
 
 		if (len > 2 && doid[0] == SSH_GSS_OIDTYPE &&
 		    doid[1] == len - 2) {
@@ -107,12 +111,12 @@ userauth_gssapi(struct ssh *ssh)
 
 	authctxt->methoddata = (void *)ctxt;
 
-	packet_start(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE);
-
 	/* Return the OID that we received */
-	packet_put_string(doid, len);
+	if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE)) != 0 ||
+	    (r = sshpkt_put_string(ssh, doid, len)) != 0 ||
+	    (r = sshpkt_send(ssh)) != 0)
+		fatal("%s: %s", __func__, ssh_err(r));
 
-	packet_send();
 	free(doid);
 
 	ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
@@ -130,36 +134,45 @@ input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
 	gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
 	gss_buffer_desc recv_tok;
 	OM_uint32 maj_status, min_status, flags;
-	u_int len;
+	u_char *p;
+	size_t len;
+	int r;
 
 	if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
 		fatal("No authentication or GSSAPI context");
 
 	gssctxt = authctxt->methoddata;
-	recv_tok.value = packet_get_string(&len);
-	recv_tok.length = len; /* u_int vs. size_t */
-
-	packet_check_eom();
+	if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
+	    (r = sshpkt_get_end(ssh)) != 0)
+		fatal("%s: %s", __func__, ssh_err(r));
 
+	recv_tok.value = p;
+	recv_tok.length = len;
 	maj_status = PRIVSEP(ssh_gssapi_accept_ctx(gssctxt, &recv_tok,
 	    &send_tok, &flags));
 
-	free(recv_tok.value);
+	free(p);
 
 	if (GSS_ERROR(maj_status)) {
 		if (send_tok.length != 0) {
-			packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
-			packet_put_string(send_tok.value, send_tok.length);
-			packet_send();
+			if ((r = sshpkt_start(ssh,
+			    SSH2_MSG_USERAUTH_GSSAPI_ERRTOK)) != 0 ||
+			    (r = sshpkt_put_string(ssh, send_tok.value,
+			    send_tok.length)) != 0 ||
+			    (r = sshpkt_send(ssh)) != 0)
+				fatal("%s: %s", __func__, ssh_err(r));
 		}
 		authctxt->postponed = 0;
 		ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
 		userauth_finish(ssh, 0, "gssapi-with-mic", NULL);
 	} else {
 		if (send_tok.length != 0) {
-			packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
-			packet_put_string(send_tok.value, send_tok.length);
-			packet_send();
+			if ((r = sshpkt_start(ssh,
+			    SSH2_MSG_USERAUTH_GSSAPI_TOKEN)) != 0 ||
+			    (r = sshpkt_put_string(ssh, send_tok.value,
+			    send_tok.length)) != 0 ||
+			    (r = sshpkt_send(ssh)) != 0)
+				fatal("%s: %s", __func__, ssh_err(r));
 		}
 		if (maj_status == GSS_S_COMPLETE) {
 			ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
@@ -185,16 +198,16 @@ input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
 	gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
 	gss_buffer_desc recv_tok;
 	OM_uint32 maj_status;
-	u_int len;
+	int r;
 
 	if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
 		fatal("No authentication or GSSAPI context");
 
 	gssctxt = authctxt->methoddata;
-	recv_tok.value = packet_get_string(&len);
-	recv_tok.length = len;
-
-	packet_check_eom();
+	if ((r = sshpkt_get_string(ssh,
+	    &recv_tok.value, &recv_tok.length)) != 0 ||
+	    (r = sshpkt_get_end(ssh)) != 0)
+		fatal("%s: %s", __func__, ssh_err(r));
 
 	/* Push the error token into GSSAPI to see what it says */
 	maj_status = PRIVSEP(ssh_gssapi_accept_ctx(gssctxt, &recv_tok,
@@ -233,7 +246,8 @@ input_gssapi_exchange_complete(int type, u_int32_t plen, struct ssh *ssh)
 	 * the dispatcher once the exchange is complete
 	 */
 
-	packet_check_eom();
+	if ((r = sshpkt_get_end(ssh)) != 0)
+		fatal("%s: %s", __func__, ssh_err(r));
 
 	authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
 
@@ -255,10 +269,9 @@ input_gssapi_mic(int type, u_int32_t plen, struct ssh *ssh)
 {
 	Authctxt *authctxt = ssh->authctxt;
 	Gssctxt *gssctxt;
-	int authenticated = 0;
-	Buffer b;
+	int r, authenticated = 0;
+	struct sshbuf *b;
 	gss_buffer_desc mic, gssbuf;
-	u_int len;
 	const char *displayname;
 
 	if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
@@ -266,21 +279,23 @@ input_gssapi_mic(int type, u_int32_t plen, struct ssh *ssh)
 
 	gssctxt = authctxt->methoddata;
 
-	mic.value = packet_get_string(&len);
-	mic.length = len;
-
-	ssh_gssapi_buildmic(&b, authctxt->user, authctxt->service,
+	if ((r = sshpkt_get_string(ssh, &mic.value, &mic.length)) != 0)
+		fatal("%s: %s", __func__, ssh_err(r));
+	if ((b = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	ssh_gssapi_buildmic(b, authctxt->user, authctxt->service,
 	    "gssapi-with-mic");
 
-	gssbuf.value = buffer_ptr(&b);
-	gssbuf.length = buffer_len(&b);
+	if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
+		fatal("%s: sshbuf_mutable_ptr failed", __func__);
+	gssbuf.length = sshbuf_len(b);
 
 	if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gssctxt, &gssbuf, &mic))))
 		authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
 	else
 		logit("GSSAPI MIC check failed");
 
-	buffer_free(&b);
+	sshbuf_free(b);
 	free(mic.value);
 
 	if ((!use_privsep || mm_is_monitor()) &&
diff --git a/usr.bin/ssh/gss-genr.c b/usr.bin/ssh/gss-genr.c
index 4055317bcaa..14e8a8d3c67 100644
--- a/usr.bin/ssh/gss-genr.c
+++ b/usr.bin/ssh/gss-genr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: gss-genr.c,v 1.24 2016/09/12 01:22:38 deraadt Exp $ */
+/* $OpenBSD: gss-genr.c,v 1.25 2018/07/09 21:37:55 markus Exp $ */
 
 /*
  * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
@@ -32,7 +32,8 @@
 #include <limits.h>
 
 #include "xmalloc.h"
-#include "buffer.h"
+#include "ssherr.h"
+#include "sshbuf.h"
 #include "log.h"
 #include "ssh2.h"
 
@@ -89,10 +90,12 @@ ssh_gssapi_last_error(Gssctxt *ctxt, OM_uint32 *major_status,
 	OM_uint32 lmin;
 	gss_buffer_desc msg = GSS_C_EMPTY_BUFFER;
 	OM_uint32 ctx;
-	Buffer b;
+	struct sshbuf *b;
 	char *ret;
+	int r;
 
-	buffer_init(&b);
+	if ((b = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
 
 	if (major_status != NULL)
 		*major_status = ctxt->major;
@@ -105,8 +108,9 @@ ssh_gssapi_last_error(Gssctxt *ctxt, OM_uint32 *major_status,
 		gss_display_status(&lmin, ctxt->major,
 		    GSS_C_GSS_CODE, ctxt->oid, &ctx, &msg);
 
-		buffer_append(&b, msg.value, msg.length);
-		buffer_put_char(&b, '\n');
+		if ((r = sshbuf_put(b, msg.value, msg.length)) != 0 ||
+		    (r = sshbuf_put_u8(b, '\n')) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
 
 		gss_release_buffer(&lmin, &msg);
 	} while (ctx != 0);
@@ -116,16 +120,17 @@ ssh_gssapi_last_error(Gssctxt *ctxt, OM_uint32 *major_status,
 		gss_display_status(&lmin, ctxt->minor,
 		    GSS_C_MECH_CODE, ctxt->oid, &ctx, &msg);
 
-		buffer_append(&b, msg.value, msg.length);
-		buffer_put_char(&b, '\n');
+		if ((r = sshbuf_put(b, msg.value, msg.length)) != 0 ||
+		    (r = sshbuf_put_u8(b, '\n')) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
 
 		gss_release_buffer(&lmin, &msg);
 	} while (ctx != 0);
 
-	buffer_put_char(&b, '\0');
-	ret = xmalloc(buffer_len(&b));
-	buffer_get(&b, ret, buffer_len(&b));
-	buffer_free(&b);
+	if ((r = sshbuf_put_u8(b, '\n')) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	ret = xstrdup((const char *)sshbuf_ptr(b));
+	sshbuf_free(b);
 	return (ret);
 }
 
@@ -233,15 +238,18 @@ ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
 }
 
 void
-ssh_gssapi_buildmic(Buffer *b, const char *user, const char *service,
+ssh_gssapi_buildmic(struct sshbuf *b, const char *user, const char *service,
     const char *context)
 {
-	buffer_init(b);
-	buffer_put_string(b, session_id2, session_id2_len);
-	buffer_put_char(b, SSH2_MSG_USERAUTH_REQUEST);
-	buffer_put_cstring(b, user);
-	buffer_put_cstring(b, service);
-	buffer_put_cstring(b, context);
+	int r;
+
+	sshbuf_reset(b);
+	if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
+	    (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
+	    (r = sshbuf_put_cstring(b, user)) != 0 ||
+	    (r = sshbuf_put_cstring(b, service)) != 0 ||
+	    (r = sshbuf_put_cstring(b, context)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
 }
 
 int
diff --git a/usr.bin/ssh/gss-serv-krb5.c b/usr.bin/ssh/gss-serv-krb5.c
index 530216bf25f..f857500f04a 100644
--- a/usr.bin/ssh/gss-serv-krb5.c
+++ b/usr.bin/ssh/gss-serv-krb5.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: gss-serv-krb5.c,v 1.8 2013/07/20 01:55:13 djm Exp $ */
+/* $OpenBSD: gss-serv-krb5.c,v 1.9 2018/07/09 21:37:55 markus Exp $ */
 
 /*
  * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
@@ -30,12 +30,11 @@
 #include <sys/types.h>
 
 #include "xmalloc.h"
-#include "key.h"
+#include "sshkey.h"
 #include "hostfile.h"
 #include "auth.h"
 #include "log.h"
 
-#include "buffer.h"
 #include "ssh-gss.h"
 
 #include <krb5.h>
diff --git a/usr.bin/ssh/gss-serv.c b/usr.bin/ssh/gss-serv.c
index add350db382..b4f4208b526 100644
--- a/usr.bin/ssh/gss-serv.c
+++ b/usr.bin/ssh/gss-serv.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: gss-serv.c,v 1.30 2017/06/24 06:34:38 djm Exp $ */
+/* $OpenBSD: gss-serv.c,v 1.31 2018/07/09 21:37:55 markus Exp $ */
 
 /*
  * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
@@ -32,8 +32,7 @@
 #include <string.h>
 
 #include "xmalloc.h"
-#include "buffer.h"
-#include "key.h"
+#include "sshkey.h"
 #include "hostfile.h"
 #include "auth.h"
 #include "log.h"