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[PATCH 6/8] connect: tell server that the client understands v1

From
BWBrandon Williams <bmwill@google.com>
Date
Sep 13, 2017, 21:54 UTC
Message-ID
<20170913215448.84674-7-bmwill@google.com>
In-Reply-To
<20170913215448.84674-1-bmwill@google.com>

Teach the connection logic to tell a serve that it understands protocol v1. This is done in 2 different ways for the built in protocols.

1. git://
   A normal request is structured as "command path/to/repo\0host=..\0"
   and due to a bug in an old version of git-daemon 73bb33a94 (daemon:
   Strictly parse the "extra arg" part of the command, 2009-06-04) we
   aren't able to place any extra args (separated by NULs) besides the
   host.  In order to get around this limitation put protocol version
   information after a second NUL byte so the request is structured
   like: "command path/to/repo\0host=..\0\0version=1\0".  git-daemon can
   then parse out the version number and set GIT_PROTOCOL.
2. ssh://, file://
   Set GIT_PROTOCOL envvar with the desired protocol version.  The
   envvar can be sent across ssh by using '-o SendEnv=GIT_PROTOCOL' and
   having the server whitelist this envvar.
Signed-off-by: Brandon Williams <bmwill@google.com>
---
 connect.c              |  37 ++++++--
 t/t5700-protocol-v1.sh | 223 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 255 insertions(+), 5 deletions(-)
 create mode 100755 t/t5700-protocol-v1.sh
diff --git a/connect.c b/connect.c
index 2702e1f2e..40b388acd 100644
--- a/connect.c
+++ b/connect.c
@@ -815,6 +815,7 @@ struct child_process *git_connect(int fd[2], const char *url,
 		printf("Diag: path=%s\n", path ? path : "NULL");
 		conn = NULL;
 	} else if (protocol == PROTO_GIT) {
+		struct strbuf request = STRBUF_INIT;
 		/*
 		 * Set up virtual host information based on where we will
 		 * connect, unless the user has overridden us in
@@ -842,12 +843,24 @@ struct child_process *git_connect(int fd[2], const char *url,
 		 * Note: Do not add any other headers here!  Doing so
 		 * will cause older git-daemon servers to crash.
 		 */
-		packet_write_fmt(fd[1],
-			     "%s %s%chost=%s%c",
-			     prog, path, 0,
-			     target_host, 0);
+		strbuf_addf(&request,
+			    "%s %s%chost=%s%c",
+			    prog, path, 0,
+			    target_host, 0);
+
+		/* If using a new version put that stuff here after a second null byte */
+		if (get_protocol_version_config() > 0) {
+			strbuf_addch(&request, '\0');
+			strbuf_addf(&request, "version=%d%c",
+				    get_protocol_version_config(), '\0');
+		}
+
+		packet_write(fd[1], request.buf, request.len);
+
 		free(target_host);
+		strbuf_release(&request);
 	} else {
+		const char *const *var;
 		conn = xmalloc(sizeof(*conn));
 		child_process_init(conn);
 
@@ -859,7 +872,9 @@ struct child_process *git_connect(int fd[2], const char *url,
 		sq_quote_buf(&cmd, path);
 
 		/* remove repo-local variables from the environment */
-		conn->env = local_repo_env;
+		for (var = local_repo_env; *var; var++)
+			argv_array_push(&conn->env_array, *var);
+
 		conn->use_shell = 1;
 		conn->in = conn->out = -1;
 		if (protocol == PROTO_SSH) {
@@ -912,6 +927,14 @@ struct child_process *git_connect(int fd[2], const char *url,
 			}
 
 			argv_array_push(&conn->args, ssh);
+
+			if (get_protocol_version_config() > 0) {
+				argv_array_push(&conn->args, "-o");
+				argv_array_push(&conn->args, "SendEnv=" GIT_PROTOCOL_ENVIRONMENT);
+				argv_array_pushf(&conn->env_array, GIT_PROTOCOL_ENVIRONMENT "=version=%d",
+						 get_protocol_version_config());
+			}
+
 			if (flags & CONNECT_IPV4)
 				argv_array_push(&conn->args, "-4");
 			else if (flags & CONNECT_IPV6)
@@ -926,6 +949,10 @@ struct child_process *git_connect(int fd[2], const char *url,
 			argv_array_push(&conn->args, ssh_host);
 		} else {
 			transport_check_allowed("file");
+			if (get_protocol_version_config() > 0) {
+				argv_array_pushf(&conn->env_array, GIT_PROTOCOL_ENVIRONMENT "=version=%d",
+						 get_protocol_version_config());
+			}
 		}
 		argv_array_push(&conn->args, cmd.buf);
 
diff --git a/t/t5700-protocol-v1.sh b/t/t5700-protocol-v1.sh
new file mode 100755
index 000000000..1988bbce6
--- /dev/null
+++ b/t/t5700-protocol-v1.sh
@@ -0,0 +1,223 @@
+#!/bin/sh
+
+test_description='test git wire-protocol transition'
+
+TEST_NO_CREATE_REPO=1
+
+. ./test-lib.sh
+
+# Test protocol v1 with 'git://' transport
+#
+. "$TEST_DIRECTORY"/lib-git-daemon.sh
+start_git_daemon --export-all --enable=receive-pack
+daemon_parent=$GIT_DAEMON_DOCUMENT_ROOT_PATH/parent
+
+test_expect_success 'create repo to be served by git-daemon' '
+	git init "$daemon_parent" &&
+	test_commit -C "$daemon_parent" one
+'
+
+test_expect_success 'clone with git:// using protocol v1' '
+	GIT_TRACE_PACKET=1 git -c protocol.version=1 \
+		clone "$GIT_DAEMON_URL/parent" daemon_child 2>log &&
+
+	git -C daemon_child log -1 --format=%s >actual &&
+	git -C "$daemon_parent" log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Client requested to use protocol v1
+	grep "version=1" log &&
+	# Server responded using protocol v1
+	grep "clone< version 1" log
+'
+
+test_expect_success 'fetch with git:// using protocol v1' '
+	test_commit -C "$daemon_parent" two &&
+
+	GIT_TRACE_PACKET=1 git -C daemon_child -c protocol.version=1 \
+		fetch 2>log &&
+
+	git -C daemon_child log -1 --format=%s FETCH_HEAD >actual &&
+	git -C "$daemon_parent" log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Client requested to use protocol v1
+	grep "version=1" log &&
+	# Server responded using protocol v1
+	grep "fetch< version 1" log
+'
+
+test_expect_success 'pull with git:// using protocol v1' '
+	GIT_TRACE_PACKET=1 git -C daemon_child -c protocol.version=1 \
+		pull 2>log &&
+
+	git -C daemon_child log -1 --format=%s >actual &&
+	git -C "$daemon_parent" log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Client requested to use protocol v1
+	grep "version=1" log &&
+	# Server responded using protocol v1
+	grep "fetch< version 1" log
+'
+
+test_expect_success 'push with git:// using protocol v1' '
+	test_commit -C daemon_child three &&
+
+	# Since the repository being served isnt bare we need to push to
+	# another branch explicitly to avoid mangling the master branch
+	GIT_TRACE_PACKET=1 git -C daemon_child -c protocol.version=1 \
+		push origin HEAD:client_branch 2>log &&
+
+	git -C daemon_child log -1 --format=%s >actual &&
+	git -C "$daemon_parent" log -1 --format=%s client_branch >expect &&
+	test_cmp expect actual &&
+
+	# Client requested to use protocol v1
+	grep "version=1" log &&
+	# Server responded using protocol v1
+	grep "push< version 1" log
+'
+
+stop_git_daemon
+
+# Test protocol v1 with 'file://' transport
+#
+test_expect_success 'create repo to be served by file:// transport' '
+	git init file_parent &&
+	test_commit -C file_parent one
+'
+
+test_expect_success 'clone with file:// using protocol v1' '
+	GIT_TRACE_PACKET=1 git -c protocol.version=1 \
+		clone "file://$(pwd)/file_parent" file_child 2>log &&
+
+	git -C file_child log -1 --format=%s >actual &&
+	git -C file_parent log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Server responded using protocol v1
+	grep "clone< version 1" log
+'
+
+test_expect_success 'fetch with file:// using protocol v1' '
+	test_commit -C file_parent two &&
+
+	GIT_TRACE_PACKET=1 git -C file_child -c protocol.version=1 \
+		fetch 2>log &&
+
+	git -C file_child log -1 --format=%s FETCH_HEAD >actual &&
+	git -C file_parent log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Server responded using protocol v1
+	grep "fetch< version 1" log
+'
+
+test_expect_success 'pull with file:// using protocol v1' '
+	GIT_TRACE_PACKET=1 git -C file_child -c protocol.version=1 \
+		pull 2>log &&
+
+	git -C file_child log -1 --format=%s >actual &&
+	git -C file_parent log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Server responded using protocol v1
+	grep "fetch< version 1" log
+'
+
+test_expect_success 'push with file:// using protocol v1' '
+	test_commit -C file_child three &&
+
+	# Since the repository being served isnt bare we need to push to
+	# another branch explicitly to avoid mangling the master branch
+	GIT_TRACE_PACKET=1 git -C file_child -c protocol.version=1 \
+		push origin HEAD:client_branch 2>log &&
+
+	git -C file_child log -1 --format=%s >actual &&
+	git -C file_parent log -1 --format=%s client_branch >expect &&
+	test_cmp expect actual &&
+
+	# Server responded using protocol v1
+	grep "push< version 1" log
+'
+
+# Test protocol v1 with 'ssh://' transport
+#
+test_expect_success 'setup ssh wrapper' '
+	GIT_SSH="$GIT_BUILD_DIR/t/helper/test-fake-ssh$X" &&
+	export GIT_SSH &&
+	export TRASH_DIRECTORY &&
+	>"$TRASH_DIRECTORY"/ssh-output
+'
+
+expect_ssh () {
+	test_when_finished '(cd "$TRASH_DIRECTORY" && rm -f ssh-expect && >ssh-output)' &&
+	echo "ssh: -o SendEnv=GIT_PROTOCOL myhost $1 '$PWD/ssh_parent'" >"$TRASH_DIRECTORY/ssh-expect" &&
+	(cd "$TRASH_DIRECTORY" && test_cmp ssh-expect ssh-output)
+}
+
+test_expect_success 'create repo to be served by ssh:// transport' '
+	git init ssh_parent &&
+	test_commit -C ssh_parent one
+'
+
+test_expect_success 'clone with ssh:// using protocol v1' '
+	GIT_TRACE_PACKET=1 git -c protocol.version=1 \
+		clone "ssh://myhost:$(pwd)/ssh_parent" ssh_child 2>log &&
+	expect_ssh git-upload-pack &&
+
+	git -C ssh_child log -1 --format=%s >actual &&
+	git -C ssh_parent log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Server responded using protocol v1
+	grep "clone< version 1" log
+'
+
+test_expect_success 'fetch with ssh:// using protocol v1' '
+	test_commit -C ssh_parent two &&
+
+	GIT_TRACE_PACKET=1 git -C ssh_child -c protocol.version=1 \
+		fetch 2>log &&
+	expect_ssh git-upload-pack &&
+
+	git -C ssh_child log -1 --format=%s FETCH_HEAD >actual &&
+	git -C ssh_parent log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Server responded using protocol v1
+	grep "fetch< version 1" log
+'
+
+test_expect_success 'pull with ssh:// using protocol v1' '
+	GIT_TRACE_PACKET=1 git -C ssh_child -c protocol.version=1 \
+		pull 2>log &&
+	expect_ssh git-upload-pack &&
+
+	git -C ssh_child log -1 --format=%s >actual &&
+	git -C ssh_parent log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+
+	# Server responded using protocol v1
+	grep "fetch< version 1" log
+'
+
+test_expect_success 'push with ssh:// using protocol v1' '
+	test_commit -C ssh_child three &&
+
+	# Since the repository being served isnt bare we need to push to
+	# another branch explicitly to avoid mangling the master branch
+	GIT_TRACE_PACKET=1 git -C ssh_child -c protocol.version=1 \
+		push origin HEAD:client_branch 2>log &&
+	expect_ssh git-receive-pack &&
+
+	git -C ssh_child log -1 --format=%s >actual &&
+	git -C ssh_parent log -1 --format=%s client_branch >expect &&
+	test_cmp expect actual &&
+
+	# Server responded using protocol v1
+	grep "push< version 1" log
+'
+
+test_done
-- 
2.14.1.690.gbb1197296e-goog
Previous: Brandon WilliamsNext: Brandon Williams
Message 17 of 161 in “protocol transition”
  1. 0/8 protocol transitionBrandon Williams, Sep 13, 2017
  2. 1/8 pkt-line: add packet_write functionBrandon Williams, Sep 13, 2017
  3. 2/8 protocol: introduce protocol extention mechanismsBrandon Williams, Sep 13, 2017
  4. Stefan BellerSep 13, 2017
  5. Brandon WilliamsSep 18, 2017
  6. Stefan BellerSep 18, 2017
  7. Brandon WilliamsSep 18, 2017
  8. Stefan BellerSep 18, 2017
  9. 3/8 daemon: recognize hidden request argumentsBrandon Williams, Sep 13, 2017
  10. Stefan BellerSep 13, 2017
  11. Brandon WilliamsSep 18, 2017
  12. Jonathan TanSep 21, 2017
  13. Jonathan TanSep 21, 2017
  14. Brandon WilliamsSep 21, 2017
  15. 5/8 connect: teach client to recognize v1 server responseBrandon Williams, Sep 13, 2017
  16. 4/8 upload-pack, receive-pack: introduce protocol version 1Brandon Williams, Sep 13, 2017
  17. 6/8 connect: tell server that the client understands v1Brandon Williams, Sep 13, 2017
  18. 8/8 i5700: add interop test for protocol transitionBrandon Williams, Sep 13, 2017
  19. 7/8 http: tell server that the client understands v1Brandon Williams, Sep 13, 2017
  20. 5/8 connect: die when a capability line comes after a refBrandon Williams, Sep 20, 2017
  21. Jeff KingSep 20, 2017
  22. Brandon WilliamsSep 20, 2017
  23. Jonathan NiederSep 20, 2017
  24. Junio C HamanoSep 21, 2017
  25. connect: in ref advertisement, shallows are lastJonathan Tan, Sep 21, 2017
  26. connect: in ref advertisement, shallows are lastJonathan Tan, Sep 21, 2017
  27. Brandon WilliamsSep 22, 2017
  28. connect: in ref advertisement, shallows are lastJonathan Tan, Sep 22, 2017
  29. Junio C HamanoSep 22, 2017
  30. Junio C HamanoSep 22, 2017
  31. Brandon WilliamsSep 22, 2017
  32. connect: in ref advertisement, shallows are lastJonathan Tan, Sep 22, 2017
  33. Brandon WilliamsSep 22, 2017
  34. Jonathan TanSep 22, 2017
  35. Junio C HamanoSep 24, 2017
  36. connect: in ref advertisement, shallows are lastJonathan Tan, Sep 26, 2017
  37. Brandon WilliamsSep 26, 2017
  38. 0/9 protocol transitionBrandon Williams, Sep 26, 2017
  39. 2/9 pkt-line: add packet_write functionBrandon Williams, Sep 26, 2017
  40. 3/9 protocol: introduce protocol extention mechanismsBrandon Williams, Sep 26, 2017
  41. Junio C HamanoSep 27, 2017
  42. Junio C HamanoSep 27, 2017
  43. Brandon WilliamsSep 29, 2017
  44. Brandon WilliamsSep 28, 2017
  45. Stefan BellerSep 27, 2017
  46. Brandon WilliamsSep 28, 2017
  47. 1/9 connect: in ref advertisement, shallows are lastBrandon Williams, Sep 26, 2017
  48. 6/9 connect: teach client to recognize v1 server responseBrandon Williams, Sep 26, 2017
  49. Junio C HamanoSep 27, 2017
  50. Brandon WilliamsSep 27, 2017
  51. Junio C HamanoSep 27, 2017
  52. Brandon WilliamsSep 28, 2017
  53. 7/9 connect: tell server that the client understands v1Brandon Williams, Sep 26, 2017
  54. Junio C HamanoSep 27, 2017
  55. Junio C HamanoSep 27, 2017
  56. Brandon WilliamsSep 29, 2017
  57. Brandon WilliamsSep 28, 2017
  58. 9/9 i5700: add interop test for protocol transitionBrandon Williams, Sep 26, 2017
  59. 8/9 http: tell server that the client understands v1Brandon Williams, Sep 26, 2017
  60. Junio C HamanoSep 27, 2017
  61. Brandon WilliamsSep 27, 2017
  62. 5/9 upload-pack, receive-pack: introduce protocol version 1Brandon Williams, Sep 26, 2017
  63. Junio C HamanoSep 27, 2017
  64. Brandon WilliamsSep 27, 2017
  65. 4/9 daemon: recognize hidden request argumentsBrandon Williams, Sep 26, 2017
  66. Junio C HamanoSep 27, 2017
  67. Brandon WilliamsSep 27, 2017
  68. Brandon WilliamsSep 28, 2017
  69. 00/10 protocol transitionBrandon Williams, Oct 3, 2017
  70. 04/10 daemon: recognize hidden request argumentsBrandon Williams, Oct 3, 2017
  71. Jonathan TanOct 10, 2017
  72. Brandon WilliamsOct 13, 2017
  73. 03/10 protocol: introduce protocol extention mechanismsBrandon Williams, Oct 3, 2017
  74. Simon RuderichOct 6, 2017
  75. Junio C HamanoOct 6, 2017
  76. Martin ÅgrenOct 6, 2017
  77. Junio C HamanoOct 6, 2017
  78. Martin ÅgrenOct 6, 2017
  79. Stefan BellerOct 6, 2017
  80. Martin ÅgrenOct 8, 2017
  81. Brandon WilliamsOct 10, 2017
  82. Jonathan NiederOct 10, 2017
  83. Stefan BellerOct 10, 2017
  84. Junio C HamanoOct 11, 2017
  85. Brandon WilliamsOct 13, 2017
  86. Martin ÅgrenOct 9, 2017
  87. Jonathan TanOct 10, 2017
  88. 02/10 pkt-line: add packet_write functionBrandon Williams, Oct 3, 2017
  89. Jonathan TanOct 10, 2017
  90. 05/10 upload-pack, receive-pack: introduce protocol version 1Brandon Williams, Oct 3, 2017
  91. Jonathan TanOct 10, 2017
  92. Brandon WilliamsOct 13, 2017
  93. 01/10 connect: in ref advertisement, shallows are lastBrandon Williams, Oct 3, 2017
  94. Jonathan TanOct 10, 2017
  95. 09/10 i5700: add interop test for protocol transitionBrandon Williams, Oct 3, 2017
  96. 08/10 http: tell server that the client understands v1Brandon Williams, Oct 3, 2017
  97. 10/10 ssh: introduce a 'simple' ssh variantBrandon Williams, Oct 3, 2017
  98. Jonathan NiederOct 3, 2017
  99. Brandon WilliamsOct 16, 2017
  100. 0/5 Coping with unrecognized ssh wrapper scripts in GIT_SSHJonathan Nieder, Oct 23, 2017
  101. 1/5 connect: split git:// setup into a separate functionJonathan Nieder, Oct 23, 2017
  102. Stefan BellerOct 23, 2017
  103. diff: add option to ignore whitespaces for move detection onlyStefan Beller, Oct 24, 2017
  104. Brandon WilliamsOct 24, 2017
  105. Junio C HamanoOct 25, 2017
  106. Junio C HamanoOct 25, 2017
  107. Brandon WilliamsOct 25, 2017
  108. Junio C HamanoOct 24, 2017
  109. Stefan BellerOct 24, 2017
  110. 2/5 connect: split ssh command line options into separate functionJonathan Nieder, Oct 23, 2017
  111. Stefan BellerOct 23, 2017
  112. 3/5 ssh: 'auto' variant to select between 'ssh' and 'simple'Jonathan Nieder, Oct 23, 2017
  113. Jonathan TanOct 23, 2017
  114. Jonathan NiederOct 23, 2017
  115. Brandon WilliamsOct 23, 2017
  116. Jonathan TanOct 23, 2017
  117. 0/5 Coping with unrecognized ssh wrapper scripts in GIT_SSHJonathan Nieder, Oct 23, 2017
  118. 1/5 connect: split git:// setup into a separate functionJonathan Nieder, Oct 23, 2017
  119. Junio C HamanoOct 24, 2017
  120. Jonathan NiederNov 15, 2017
  121. Junio C HamanoNov 17, 2017
  122. 2/5 connect: split ssh command line options into separate functionJonathan Nieder, Oct 23, 2017
  123. Junio C HamanoOct 24, 2017
  124. 3/5 ssh: 'auto' variant to select between 'ssh' and 'simple'Jonathan Nieder, Oct 23, 2017
  125. Brandon WilliamsOct 23, 2017
  126. Stefan BellerOct 23, 2017
  127. 4/5 ssh: 'simple' variant does not support -4/-6Jonathan Nieder, Oct 23, 2017
  128. 5/5 ssh: 'simple' variant does not support --portJonathan Nieder, Oct 23, 2017
  129. Junio C HamanoOct 24, 2017
  130. Jonathan NiederOct 23, 2017
  131. Stefan BellerOct 23, 2017
  132. Jonathan NiederOct 23, 2017
  133. Junio C HamanoOct 24, 2017
  134. Johannes SchindelinOct 25, 2017
  135. Stefan BellerOct 25, 2017
  136. Jonathan NiederOct 25, 2017
  137. Junio C HamanoOct 30, 2017
  138. Johannes SchindelinOct 30, 2017
  139. 4/5 ssh: 'simple' variant does not support -4/-6Jonathan Nieder, Oct 23, 2017
  140. 5/5 ssh: 'simple' variant does not support --portJonathan Nieder, Oct 23, 2017
  141. Stefan BellerOct 23, 2017
  142. 07/10 connect: tell server that the client understands v1Brandon Williams, Oct 3, 2017
  143. Jonathan TanOct 10, 2017
  144. Brandon WilliamsOct 13, 2017
  145. 06/10 connect: teach client to recognize v1 server responseBrandon Williams, Oct 3, 2017
  146. Junio C HamanoOct 4, 2017
  147. Documentation: document Extra ParametersJonathan Tan, Oct 10, 2017
  148. Brandon WilliamsOct 13, 2017
  149. 00/11 protocol transitionBrandon Williams, Oct 16, 2017
  150. 01/11 connect: in ref advertisement, shallows are lastBrandon Williams, Oct 16, 2017
  151. 02/11 pkt-line: add packet_write functionBrandon Williams, Oct 16, 2017
  152. 03/11 protocol: introduce protocol extension mechanismsBrandon Williams, Oct 16, 2017
  153. Kevin DaudtOct 16, 2017
  154. 06/11 connect: teach client to recognize v1 server responseBrandon Williams, Oct 16, 2017
  155. 04/11 daemon: recognize hidden request argumentsBrandon Williams, Oct 16, 2017
  156. 09/11 i5700: add interop test for protocol transitionBrandon Williams, Oct 16, 2017
  157. 08/11 http: tell server that the client understands v1Brandon Williams, Oct 16, 2017
  158. 05/11 upload-pack, receive-pack: introduce protocol version 1Brandon Williams, Oct 16, 2017
  159. 07/11 connect: tell server that the client understands v1Brandon Williams, Oct 16, 2017
  160. 10/11 ssh: introduce a 'simple' ssh variantBrandon Williams, Oct 16, 2017
  161. 11/11 Documentation: document Extra ParametersBrandon Williams, Oct 16, 2017

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