diff options
| -rw-r--r-- | Documentation/technical/protocol-v2.txt | 6 | ||||
| -rw-r--r-- | ls-refs.c | 22 | ||||
| -rw-r--r-- | serve.c | 120 | ||||
| -rwxr-xr-x | t/t5701-git-serve.sh | 75 |
4 files changed, 164 insertions, 59 deletions
diff --git a/Documentation/technical/protocol-v2.txt b/Documentation/technical/protocol-v2.txt index 59b86fcf97..21e8258ccf 100644 --- a/Documentation/technical/protocol-v2.txt +++ b/Documentation/technical/protocol-v2.txt @@ -199,7 +199,11 @@ ls-refs takes in the following arguments: Show peeled tags. ref-prefix <prefix> When specified, only references having a prefix matching one of - the provided prefixes are displayed. + the provided prefixes are displayed. Multiple instances may be + given, in which case references matching any prefix will be + shown. Note that this is purely for optimization; a server MAY + show refs not matching the prefix if it chooses, and clients + should filter the result themselves. If the 'unborn' feature is advertised the following argument can be included in the client's request. @@ -41,6 +41,12 @@ static void ensure_config_read(void) } /* + * If we see this many or more "ref-prefix" lines from the client, we consider + * it "too many" and will avoid using the prefix feature entirely. + */ +#define TOO_MANY_PREFIXES 65536 + +/* * Check if one of the prefixes is a prefix of the ref. * If no prefixes were provided, all refs match. */ @@ -158,15 +164,27 @@ int ls_refs(struct repository *r, struct packet_reader *request) data.peel = 1; else if (!strcmp("symrefs", arg)) data.symrefs = 1; - else if (skip_prefix(arg, "ref-prefix ", &out)) - strvec_push(&data.prefixes, out); + else if (skip_prefix(arg, "ref-prefix ", &out)) { + if (data.prefixes.nr < TOO_MANY_PREFIXES) + strvec_push(&data.prefixes, out); + } else if (!strcmp("unborn", arg)) data.unborn = allow_unborn; + else + die(_("unexpected line: '%s'"), arg); } if (request->status != PACKET_READ_FLUSH) die(_("expected flush after ls-refs arguments")); + /* + * If we saw too many prefixes, we must avoid using them at all; as + * soon as we have any prefix, they are meant to form a comprehensive + * list. + */ + if (data.prefixes.nr >= TOO_MANY_PREFIXES) + strvec_clear(&data.prefixes); + send_possibly_unborn_head(&data); if (!data.prefixes.nr) strvec_push(&data.prefixes, ""); @@ -10,6 +10,7 @@ #include "upload-pack.h" static int advertise_sid = -1; +static int client_hash_algo = GIT_HASH_SHA1; static int always_advertise(struct repository *r, struct strbuf *value) @@ -33,6 +34,17 @@ static int object_format_advertise(struct repository *r, return 1; } +static void object_format_receive(struct repository *r, + const char *algo_name) +{ + if (!algo_name) + die("object-format capability requires an argument"); + + client_hash_algo = hash_algo_by_name(algo_name); + if (client_hash_algo == GIT_HASH_UNKNOWN) + die("unknown object format '%s'", algo_name); +} + static int session_id_advertise(struct repository *r, struct strbuf *value) { if (advertise_sid == -1 && @@ -45,6 +57,14 @@ static int session_id_advertise(struct repository *r, struct strbuf *value) return 1; } +static void session_id_receive(struct repository *r, + const char *client_sid) +{ + if (!client_sid) + client_sid = ""; + trace2_data_string("transfer", NULL, "client-sid", client_sid); +} + struct protocol_capability { /* * The name of the capability. The server uses this name when @@ -70,6 +90,16 @@ struct protocol_capability { * This field should be NULL for capabilities which are not commands. */ int (*command)(struct repository *r, struct packet_reader *request); + + /* + * Function called when a client requests the capability as a + * non-command. This may be NULL if the capability does nothing. + * + * For a capability of the form "foo=bar", the value string points to + * the content after the "=" (i.e., "bar"). For simple capabilities + * (just "foo"), it is NULL. + */ + void (*receive)(struct repository *r, const char *value); }; static struct protocol_capability capabilities[] = { @@ -94,10 +124,12 @@ static struct protocol_capability capabilities[] = { { .name = "object-format", .advertise = object_format_advertise, + .receive = object_format_receive, }, { .name = "session-id", .advertise = session_id_advertise, + .receive = session_id_receive, }, { .name = "object-info", @@ -139,7 +171,7 @@ void protocol_v2_advertise_capabilities(void) strbuf_release(&value); } -static struct protocol_capability *get_capability(const char *key) +static struct protocol_capability *get_capability(const char *key, const char **value) { int i; @@ -149,31 +181,46 @@ static struct protocol_capability *get_capability(const char *key) for (i = 0; i < ARRAY_SIZE(capabilities); i++) { struct protocol_capability *c = &capabilities[i]; const char *out; - if (skip_prefix(key, c->name, &out) && (!*out || *out == '=')) + if (!skip_prefix(key, c->name, &out)) + continue; + if (!*out) { + *value = NULL; return c; + } + if (*out++ == '=') { + *value = out; + return c; + } } return NULL; } -static int is_valid_capability(const char *key) +static int receive_client_capability(const char *key) { - const struct protocol_capability *c = get_capability(key); + const char *value; + const struct protocol_capability *c = get_capability(key, &value); - return c && c->advertise(the_repository, NULL); + if (!c || c->command || !c->advertise(the_repository, NULL)) + return 0; + + if (c->receive) + c->receive(the_repository, value); + return 1; } -static int is_command(const char *key, struct protocol_capability **command) +static int parse_command(const char *key, struct protocol_capability **command) { const char *out; if (skip_prefix(key, "command=", &out)) { - struct protocol_capability *cmd = get_capability(out); + const char *value; + struct protocol_capability *cmd = get_capability(out, &value); if (*command) die("command '%s' requested after already requesting command '%s'", out, (*command)->name); - if (!cmd || !cmd->advertise(the_repository, NULL) || !cmd->command) + if (!cmd || !cmd->advertise(the_repository, NULL) || !cmd->command || value) die("invalid command '%s'", out); *command = cmd; @@ -183,42 +230,6 @@ static int is_command(const char *key, struct protocol_capability **command) return 0; } -static int has_capability(const struct strvec *keys, const char *capability, - const char **value) -{ - int i; - for (i = 0; i < keys->nr; i++) { - const char *out; - if (skip_prefix(keys->v[i], capability, &out) && - (!*out || *out == '=')) { - if (value) { - if (*out == '=') - out++; - *value = out; - } - return 1; - } - } - - return 0; -} - -static void check_algorithm(struct repository *r, struct strvec *keys) -{ - int client = GIT_HASH_SHA1, server = hash_algo_by_ptr(r->hash_algo); - const char *algo_name; - - if (has_capability(keys, "object-format", &algo_name)) { - client = hash_algo_by_name(algo_name); - if (client == GIT_HASH_UNKNOWN) - die("unknown object format '%s'", algo_name); - } - - if (client != server) - die("mismatched object format: server %s; client %s\n", - r->hash_algo->name, hash_algos[client].name); -} - enum request_state { PROCESS_REQUEST_KEYS, PROCESS_REQUEST_DONE, @@ -228,9 +239,8 @@ static int process_request(void) { enum request_state state = PROCESS_REQUEST_KEYS; struct packet_reader reader; - struct strvec keys = STRVEC_INIT; + int seen_capability_or_command = 0; struct protocol_capability *command = NULL; - const char *client_sid; packet_reader_init(&reader, 0, NULL, 0, PACKET_READ_CHOMP_NEWLINE | @@ -250,10 +260,9 @@ static int process_request(void) case PACKET_READ_EOF: BUG("Should have already died when seeing EOF"); case PACKET_READ_NORMAL: - /* collect request; a sequence of keys and values */ - if (is_command(reader.line, &command) || - is_valid_capability(reader.line)) - strvec_push(&keys, reader.line); + if (parse_command(reader.line, &command) || + receive_client_capability(reader.line)) + seen_capability_or_command = 1; else die("unknown capability '%s'", reader.line); @@ -265,7 +274,7 @@ static int process_request(void) * If no command and no keys were given then the client * wanted to terminate the connection. */ - if (!keys.nr) + if (!seen_capability_or_command) return 1; /* @@ -292,14 +301,13 @@ static int process_request(void) if (!command) die("no command requested"); - check_algorithm(the_repository, &keys); - - if (has_capability(&keys, "session-id", &client_sid)) - trace2_data_string("transfer", NULL, "client-sid", client_sid); + if (client_hash_algo != hash_algo_by_ptr(the_repository->hash_algo)) + die("mismatched object format: server %s; client %s\n", + the_repository->hash_algo->name, + hash_algos[client_hash_algo].name); command->command(the_repository, &reader); - strvec_clear(&keys); return 0; } diff --git a/t/t5701-git-serve.sh b/t/t5701-git-serve.sh index 930721f053..aa1827d841 100755 --- a/t/t5701-git-serve.sh +++ b/t/t5701-git-serve.sh @@ -72,6 +72,37 @@ test_expect_success 'request invalid command' ' test_i18ngrep "invalid command" err ' +test_expect_success 'request capability as command' ' + test-tool pkt-line pack >in <<-EOF && + command=agent + object-format=$(test_oid algo) + 0000 + EOF + test_must_fail test-tool serve-v2 --stateless-rpc 2>err <in && + grep invalid.command.*agent err +' + +test_expect_success 'request command as capability' ' + test-tool pkt-line pack >in <<-EOF && + command=ls-refs + object-format=$(test_oid algo) + fetch + 0000 + EOF + test_must_fail test-tool serve-v2 --stateless-rpc 2>err <in && + grep unknown.capability err +' + +test_expect_success 'requested command is command=value' ' + test-tool pkt-line pack >in <<-EOF && + command=ls-refs=whatever + object-format=$(test_oid algo) + 0000 + EOF + test_must_fail test-tool serve-v2 --stateless-rpc 2>err <in && + grep invalid.command.*ls-refs=whatever err +' + test_expect_success 'wrong object-format' ' test-tool pkt-line pack >in <<-EOF && command=fetch @@ -116,6 +147,19 @@ test_expect_success 'basics of ls-refs' ' test_cmp expect actual ' +test_expect_success 'ls-refs complains about unknown options' ' + test-tool pkt-line pack >in <<-EOF && + command=ls-refs + object-format=$(test_oid algo) + 0001 + no-such-arg + 0000 + EOF + + test_must_fail test-tool serve-v2 --stateless-rpc 2>err <in && + grep unexpected.line.*no-such-arg err +' + test_expect_success 'basic ref-prefixes' ' test-tool pkt-line pack >in <<-EOF && command=ls-refs @@ -158,6 +202,37 @@ test_expect_success 'refs/heads prefix' ' test_cmp expect actual ' +test_expect_success 'ignore very large set of prefixes' ' + # generate a large number of ref-prefixes that we expect + # to match nothing; the value here exceeds TOO_MANY_PREFIXES + # from ls-refs.c. + { + echo command=ls-refs && + echo object-format=$(test_oid algo) && + echo 0001 && + perl -le "print \"ref-prefix refs/heads/\$_\" for (1..65536)" && + echo 0000 + } | + test-tool pkt-line pack >in && + + # and then confirm that we see unmatched prefixes anyway (i.e., + # that the prefix was not applied). + cat >expect <<-EOF && + $(git rev-parse HEAD) HEAD + $(git rev-parse refs/heads/dev) refs/heads/dev + $(git rev-parse refs/heads/main) refs/heads/main + $(git rev-parse refs/heads/release) refs/heads/release + $(git rev-parse refs/tags/annotated-tag) refs/tags/annotated-tag + $(git rev-parse refs/tags/one) refs/tags/one + $(git rev-parse refs/tags/two) refs/tags/two + 0000 + EOF + + test-tool serve-v2 --stateless-rpc <in >out && + test-tool pkt-line unpack <out >actual && + test_cmp expect actual +' + test_expect_success 'peel parameter' ' test-tool pkt-line pack >in <<-EOF && command=ls-refs |