From: Andre Noll <maan@tuebingen.mpg.de>
Date: Sun, 4 Dec 2016 10:10:36 +0000 (+0100)
Subject: Merge branch 'refs/heads/t/sideband-cleanup'
X-Git-Tag: v0.5.7~22
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=f80453b693e6d3ce5450755310faf5e5d6e5c143;hp=33692c33f2effa9620064aec44c6196a8d830d05

Merge branch 'refs/heads/t/sideband-cleanup'

started on 2016-07-03, cooking since 2016-07-16

para_server announces sideband as an optional feature, which is
pointless since sideband connections have become mandatory in
paraslash-0.5.x, so they are always used. This patch set removes
the feature negitiation during the initial handshake. The sideband
protocol remains and is not affected.

Overwiew of the handshake in v0.5.x:
	(SA) server announces sideband
	(CC) client fails connection if server did not announce sideband
	(CR) client requests sideband
	(SC) server fails connection if sideband was not requested
	already broken
		- client-0.4/server-0.5 (!CR, SC)
		- client-0.5/server-0.4 (!SA, CC)

Conversion plan:
	rm (CC): breaks nothing
	rm (SC): breaks nothing
	rm (CR): breaks cl-0.6/server-0.5 (!CR, SC)
	rm (SA): breaks cl-0.5/server-0.6 (!SA, CC)
	server fails connection if client requests sideband

In this series only the first two conversion steps are done as they
can be merged early without breaking anything.

* refs/heads/t/sideband-cleanup:
  server: Do not fail if client does not request sideband.
  client: No longer fail connection if sideband was not announced.
---

diff --git a/client_common.c b/client_common.c
index cd1ccc61..eea7510f 100644
--- a/client_common.c
+++ b/client_common.c
@@ -292,11 +292,6 @@ static int client_post_select(struct sched *s, void *context)
 		if (ret < 0 || n == 0)
 			goto out;
 		ct->features = parse_features(buf);
-		if (!has_feature("sideband", ct)) {
-			PARA_ERROR_LOG("server has no sideband support\n");
-			ret = -E_INCOMPAT_FEAT;
-			goto out;
-		}
 		ct->status = CL_RECEIVED_WELCOME;
 		return 0;
 	case CL_RECEIVED_WELCOME: /* send auth command */
diff --git a/command.c b/command.c
index 93de2d2d..0eb4efc2 100644
--- a/command.c
+++ b/command.c
@@ -807,7 +807,6 @@ static void reset_signals(void)
 }
 
 struct connection_features {
-	bool sideband_requested;
 	bool aes_ctr128_requested;
 };
 
@@ -835,8 +834,8 @@ static int parse_auth_request(char *buf, int len, struct user **u,
 		create_argv(p, ",", &features);
 		for (i = 0; features[i]; i++) {
 			if (strcmp(features[i], "sideband") == 0)
-				cf->sideband_requested = true;
-			else if (strcmp(features[i], "aes_ctr128") == 0)
+				continue;
+			if (strcmp(features[i], "aes_ctr128") == 0)
 				cf->aes_ctr128_requested = true;
 			else {
 				ret = -E_BAD_FEATURE;
@@ -949,11 +948,6 @@ __noreturn void handle_connect(int fd, const char *peername)
 	ret = parse_auth_request(buf, ret, &cc->u, &cf);
 	if (ret < 0)
 		goto net_err;
-	if (!cf.sideband_requested) { /* sideband is mandatory */
-		PARA_ERROR_LOG("client did not request sideband\n");
-		ret = -E_BAD_FEATURE;
-		goto net_err;
-	}
 	if (cc->u) {
 		get_random_bytes_or_die(rand_buf, sizeof(rand_buf));
 		ret = pub_encrypt(cc->u->pubkey, rand_buf, sizeof(rand_buf),
diff --git a/error.h b/error.h
index 337160c9..3fda5787 100644
--- a/error.h
+++ b/error.h
@@ -306,7 +306,6 @@ extern const char **para_errlist[];
 	PARA_ERROR(SERVER_EOF, "connection closed by para_server"), \
 	PARA_ERROR(SERVER_CMD_SUCCESS, "command terminated successfully"), \
 	PARA_ERROR(SERVER_CMD_FAILURE, "command failed"), \
-	PARA_ERROR(INCOMPAT_FEAT, "client/server incompatibility"), \
 
 
 #define NET_ERRORS \