From b7b744f297b736c51636407f5883b3777bb36433 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Mon, 8 May 2017 14:33:50 -0700 Subject: docs: correct receive.advertisePushOptions default In commit c714e45 ("receive-pack: implement advertising and receiving push options", 2016-07-14), receive-pack was taught to (among other things) advertise that it understood push options, depending on configuration. It was documented that it advertised such ability by default; however, it actually does not. (In that commit, notice that advertise_push_options defaults to 0, unlike advertise_atomic_push which defaults to 1.) Update the documentation to state that it does not advertise the ability by default. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano diff --git a/Documentation/config.txt b/Documentation/config.txt index e43d147..5eb326e 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -2537,9 +2537,8 @@ receive.advertiseAtomic:: capability, set this variable to false. receive.advertisePushOptions:: - By default, git-receive-pack will advertise the push options - capability to its clients. If you don't want to advertise this - capability, set this variable to false. + When set to true, git-receive-pack will advertise the push options + capability to its clients. False by default. receive.autogc:: By default, git-receive-pack will run "git-gc --auto" after -- cgit v0.10.2-6-g49f6 From cbaf82cc6b734244a9190c3341ca5f08f8d5acc4 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Tue, 9 May 2017 12:23:53 -0700 Subject: receive-pack: verify push options in cert In commit f6a4e61 ("push: accept push options", 2016-07-14), send-pack was taught to include push options both within the signed cert (if the push is a signed push) and outside the signed cert; however, receive-pack ignores push options within the cert, only handling push options outside the cert. Teach receive-pack, in the case that push options are provided for a signed push, to verify that the push options both within the cert and outside the cert are consistent. This sets in stone the requirement that send-pack redundantly send its push options in 2 places, but I think that this is better than the alternatives. Sending push options only within the cert is backwards-incompatible with existing Git servers (which read push options only from outside the cert), and sending push options only outside the cert means that the push options are not signed for. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt index c59ac99..d7358f7 100644 --- a/Documentation/technical/pack-protocol.txt +++ b/Documentation/technical/pack-protocol.txt @@ -468,13 +468,10 @@ that it wants to update, it sends a line listing the obj-id currently on the server, the obj-id the client would like to update it to and the name of the reference. -This list is followed by a flush-pkt. Then the push options are transmitted -one per packet followed by another flush-pkt. After that the packfile that -should contain all the objects that the server will need to complete the new -references will be sent. +This list is followed by a flush-pkt. ---- - update-request = *shallow ( command-list | push-cert ) [packfile] + update-requests = *shallow ( command-list | push-cert ) shallow = PKT-LINE("shallow" SP obj-id) @@ -495,12 +492,35 @@ references will be sent. PKT-LINE("pusher" SP ident LF) PKT-LINE("pushee" SP url LF) PKT-LINE("nonce" SP nonce LF) + *PKT-LINE("push-option" SP push-option LF) PKT-LINE(LF) *PKT-LINE(command LF) *PKT-LINE(gpg-signature-lines LF) PKT-LINE("push-cert-end" LF) - packfile = "PACK" 28*(OCTET) + push-option = 1*( VCHAR | SP ) +---- + +If the server has advertised the 'push-options' capability and the client has +specified 'push-options' as part of the capability list above, the client then +sends its push options followed by a flush-pkt. + +---- + push-options = *PKT-LINE(push-option) flush-pkt +---- + +For backwards compatibility with older Git servers, if the client sends a push +cert and push options, it MUST send its push options both embedded within the +push cert and after the push cert. (Note that the push options within the cert +are prefixed, but the push options after the cert are not.) Both these lists +MUST be the same, modulo the prefix. + +After that the packfile that +should contain all the objects that the server will need to complete the new +references will be sent. + +---- + packfile = "PACK" 28*(OCTET) ---- If the receiving end does not support delete-refs, the sending end MUST diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index b618d52..ed21142 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -470,7 +470,8 @@ static char *prepare_push_cert_nonce(const char *path, unsigned long stamp) * after dropping "_commit" from its name and possibly moving it out * of commit.c */ -static char *find_header(const char *msg, size_t len, const char *key) +static char *find_header(const char *msg, size_t len, const char *key, + const char **next_line) { int key_len = strlen(key); const char *line = msg; @@ -483,6 +484,8 @@ static char *find_header(const char *msg, size_t len, const char *key) if (line + key_len < eol && !memcmp(line, key, key_len) && line[key_len] == ' ') { int offset = key_len + 1; + if (next_line) + *next_line = *eol ? eol + 1 : eol; return xmemdupz(line + offset, (eol - line) - offset); } line = *eol ? eol + 1 : NULL; @@ -492,7 +495,7 @@ static char *find_header(const char *msg, size_t len, const char *key) static const char *check_nonce(const char *buf, size_t len) { - char *nonce = find_header(buf, len, "nonce"); + char *nonce = find_header(buf, len, "nonce", NULL); unsigned long stamp, ostamp; char *bohmac, *expect = NULL; const char *retval = NONCE_BAD; @@ -572,6 +575,45 @@ leave: return retval; } +/* + * Return 1 if there is no push_cert or if the push options in push_cert are + * the same as those in the argument; 0 otherwise. + */ +static int check_cert_push_options(const struct string_list *push_options) +{ + const char *buf = push_cert.buf; + int len = push_cert.len; + + char *option; + const char *next_line; + int options_seen = 0; + + int retval = 1; + + if (!len) + return 1; + + while ((option = find_header(buf, len, "push-option", &next_line))) { + len -= (next_line - buf); + buf = next_line; + options_seen++; + if (options_seen > push_options->nr + || strcmp(option, + push_options->items[options_seen - 1].string)) { + retval = 0; + goto leave; + } + free(option); + } + + if (options_seen != push_options->nr) + retval = 0; + +leave: + free(option); + return retval; +} + static void prepare_push_cert_sha1(struct child_process *proc) { static int already_done; @@ -1924,6 +1966,11 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix) if (use_push_options) read_push_options(&push_options); + if (!check_cert_push_options(&push_options)) { + struct command *cmd; + for (cmd = commands; cmd; cmd = cmd->next) + cmd->error_string = "inconsistent push options"; + } prepare_shallow_info(&si, &shallow); if (!si.nr_ours && !si.nr_theirs) diff --git a/t/t5534-push-signed.sh b/t/t5534-push-signed.sh index ecb8d44..5bcb288 100755 --- a/t/t5534-push-signed.sh +++ b/t/t5534-push-signed.sh @@ -124,6 +124,43 @@ test_expect_success GPG 'signed push sends push certificate' ' test_cmp expect dst/push-cert-status ' +test_expect_success GPG 'inconsistent push options in signed push not allowed' ' + # First, invoke receive-pack with dummy input to obtain its preamble. + prepare_dst && + git -C dst config receive.certnonceseed sekrit && + git -C dst config receive.advertisepushoptions 1 && + printf xxxx | test_might_fail git receive-pack dst >preamble && + + # Then, invoke push. Simulate a receive-pack that sends the preamble we + # obtained, followed by a dummy packet. + write_script myscript <<-\EOF && + cat preamble && + printf xxxx && + cat >push + EOF + test_might_fail git push --push-option="foo" --push-option="bar" \ + --receive-pack="\"$(pwd)/myscript\"" --signed dst --delete ff && + + # Replay the push output on a fresh dst, checking that ff is truly + # deleted. + prepare_dst && + git -C dst config receive.certnonceseed sekrit && + git -C dst config receive.advertisepushoptions 1 && + git receive-pack dst push.tweak && + prepare_dst && + git -C dst config receive.certnonceseed sekrit && + git -C dst config receive.advertisepushoptions 1 && + git receive-pack dst out && + git -C dst rev-parse ff && + grep "inconsistent push options" out +' + test_expect_success GPG 'fail without key and heed user.signingkey' ' prepare_dst && mkdir -p dst/.git/hooks && -- cgit v0.10.2-6-g49f6