mirror of
https://github.com/git/git
synced 2024-08-27 11:39:22 +00:00
![Jeff King](/assets/img/avatar_default.png)
Pushing into the currently checked out branch of a non-bare repository can be dangerous; the HEAD then loses sync with the index and working tree, and it looks in the receiving repo as if the pushed changes have been reverted in the index (since they were never there in the first place). This patch adds a safety valve that checks for this condition and either generates a warning or denies the update. We trigger the check only on a non-bare repository, since a bare repo does not have a working tree (and in fact, pushing to the HEAD branch is a common workflow for publishing repositories). The behavior is configurable via receive.denyCurrentBranch, defaulting to "warn" so as not to break existing setups (though it may, after a deprecation period, switch to "refuse" by default). For users who know what they are doing and want to silence the warning (e.g., because they have a post-receive hook that reconciles the HEAD and working tree), they can turn off the warning by setting it to false or "ignore". Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
635 lines
15 KiB
C
635 lines
15 KiB
C
#include "cache.h"
|
|
#include "pack.h"
|
|
#include "refs.h"
|
|
#include "pkt-line.h"
|
|
#include "run-command.h"
|
|
#include "exec_cmd.h"
|
|
#include "commit.h"
|
|
#include "object.h"
|
|
#include "remote.h"
|
|
#include "transport.h"
|
|
|
|
static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
|
|
|
|
enum deny_action {
|
|
DENY_IGNORE,
|
|
DENY_WARN,
|
|
DENY_REFUSE,
|
|
};
|
|
|
|
static int deny_deletes = 0;
|
|
static int deny_non_fast_forwards = 0;
|
|
static enum deny_action deny_current_branch = DENY_WARN;
|
|
static int receive_fsck_objects;
|
|
static int receive_unpack_limit = -1;
|
|
static int transfer_unpack_limit = -1;
|
|
static int unpack_limit = 100;
|
|
static int report_status;
|
|
|
|
static char capabilities[] = " report-status delete-refs ";
|
|
static int capabilities_sent;
|
|
|
|
static enum deny_action parse_deny_action(const char *var, const char *value)
|
|
{
|
|
if (value) {
|
|
if (!strcasecmp(value, "ignore"))
|
|
return DENY_IGNORE;
|
|
if (!strcasecmp(value, "warn"))
|
|
return DENY_WARN;
|
|
if (!strcasecmp(value, "refuse"))
|
|
return DENY_REFUSE;
|
|
}
|
|
if (git_config_bool(var, value))
|
|
return DENY_REFUSE;
|
|
return DENY_IGNORE;
|
|
}
|
|
|
|
static int receive_pack_config(const char *var, const char *value, void *cb)
|
|
{
|
|
if (strcmp(var, "receive.denydeletes") == 0) {
|
|
deny_deletes = git_config_bool(var, value);
|
|
return 0;
|
|
}
|
|
|
|
if (strcmp(var, "receive.denynonfastforwards") == 0) {
|
|
deny_non_fast_forwards = git_config_bool(var, value);
|
|
return 0;
|
|
}
|
|
|
|
if (strcmp(var, "receive.unpacklimit") == 0) {
|
|
receive_unpack_limit = git_config_int(var, value);
|
|
return 0;
|
|
}
|
|
|
|
if (strcmp(var, "transfer.unpacklimit") == 0) {
|
|
transfer_unpack_limit = git_config_int(var, value);
|
|
return 0;
|
|
}
|
|
|
|
if (strcmp(var, "receive.fsckobjects") == 0) {
|
|
receive_fsck_objects = git_config_bool(var, value);
|
|
return 0;
|
|
}
|
|
|
|
if (!strcmp(var, "receive.denycurrentbranch")) {
|
|
deny_current_branch = parse_deny_action(var, value);
|
|
return 0;
|
|
}
|
|
|
|
return git_default_config(var, value, cb);
|
|
}
|
|
|
|
static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
|
|
{
|
|
if (capabilities_sent)
|
|
packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
|
|
else
|
|
packet_write(1, "%s %s%c%s\n",
|
|
sha1_to_hex(sha1), path, 0, capabilities);
|
|
capabilities_sent = 1;
|
|
return 0;
|
|
}
|
|
|
|
static void write_head_info(void)
|
|
{
|
|
for_each_ref(show_ref, NULL);
|
|
if (!capabilities_sent)
|
|
show_ref("capabilities^{}", null_sha1, 0, NULL);
|
|
|
|
}
|
|
|
|
struct command {
|
|
struct command *next;
|
|
const char *error_string;
|
|
unsigned char old_sha1[20];
|
|
unsigned char new_sha1[20];
|
|
char ref_name[FLEX_ARRAY]; /* more */
|
|
};
|
|
|
|
static struct command *commands;
|
|
|
|
static const char pre_receive_hook[] = "hooks/pre-receive";
|
|
static const char post_receive_hook[] = "hooks/post-receive";
|
|
|
|
static int hook_status(int code, const char *hook_name)
|
|
{
|
|
switch (code) {
|
|
case 0:
|
|
return 0;
|
|
case -ERR_RUN_COMMAND_FORK:
|
|
return error("hook fork failed");
|
|
case -ERR_RUN_COMMAND_EXEC:
|
|
return error("hook execute failed");
|
|
case -ERR_RUN_COMMAND_PIPE:
|
|
return error("hook pipe failed");
|
|
case -ERR_RUN_COMMAND_WAITPID:
|
|
return error("waitpid failed");
|
|
case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
|
|
return error("waitpid is confused");
|
|
case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
|
|
return error("%s died of signal", hook_name);
|
|
case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
|
|
return error("%s died strangely", hook_name);
|
|
default:
|
|
error("%s exited with error code %d", hook_name, -code);
|
|
return -code;
|
|
}
|
|
}
|
|
|
|
static int run_hook(const char *hook_name)
|
|
{
|
|
static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
|
|
struct command *cmd;
|
|
struct child_process proc;
|
|
const char *argv[2];
|
|
int have_input = 0, code;
|
|
|
|
for (cmd = commands; !have_input && cmd; cmd = cmd->next) {
|
|
if (!cmd->error_string)
|
|
have_input = 1;
|
|
}
|
|
|
|
if (!have_input || access(hook_name, X_OK) < 0)
|
|
return 0;
|
|
|
|
argv[0] = hook_name;
|
|
argv[1] = NULL;
|
|
|
|
memset(&proc, 0, sizeof(proc));
|
|
proc.argv = argv;
|
|
proc.in = -1;
|
|
proc.stdout_to_stderr = 1;
|
|
|
|
code = start_command(&proc);
|
|
if (code)
|
|
return hook_status(code, hook_name);
|
|
for (cmd = commands; cmd; cmd = cmd->next) {
|
|
if (!cmd->error_string) {
|
|
size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
|
|
sha1_to_hex(cmd->old_sha1),
|
|
sha1_to_hex(cmd->new_sha1),
|
|
cmd->ref_name);
|
|
if (write_in_full(proc.in, buf, n) != n)
|
|
break;
|
|
}
|
|
}
|
|
close(proc.in);
|
|
return hook_status(finish_command(&proc), hook_name);
|
|
}
|
|
|
|
static int run_update_hook(struct command *cmd)
|
|
{
|
|
static const char update_hook[] = "hooks/update";
|
|
struct child_process proc;
|
|
const char *argv[5];
|
|
|
|
if (access(update_hook, X_OK) < 0)
|
|
return 0;
|
|
|
|
argv[0] = update_hook;
|
|
argv[1] = cmd->ref_name;
|
|
argv[2] = sha1_to_hex(cmd->old_sha1);
|
|
argv[3] = sha1_to_hex(cmd->new_sha1);
|
|
argv[4] = NULL;
|
|
|
|
memset(&proc, 0, sizeof(proc));
|
|
proc.argv = argv;
|
|
proc.no_stdin = 1;
|
|
proc.stdout_to_stderr = 1;
|
|
|
|
return hook_status(run_command(&proc), update_hook);
|
|
}
|
|
|
|
static int is_ref_checked_out(const char *ref)
|
|
{
|
|
unsigned char sha1[20];
|
|
const char *head;
|
|
|
|
if (is_bare_repository())
|
|
return 0;
|
|
|
|
head = resolve_ref("HEAD", sha1, 0, NULL);
|
|
if (!head)
|
|
return 0;
|
|
return !strcmp(head, ref);
|
|
}
|
|
|
|
static const char *update(struct command *cmd)
|
|
{
|
|
const char *name = cmd->ref_name;
|
|
unsigned char *old_sha1 = cmd->old_sha1;
|
|
unsigned char *new_sha1 = cmd->new_sha1;
|
|
struct ref_lock *lock;
|
|
|
|
/* only refs/... are allowed */
|
|
if (prefixcmp(name, "refs/") || check_ref_format(name + 5)) {
|
|
error("refusing to create funny ref '%s' remotely", name);
|
|
return "funny refname";
|
|
}
|
|
|
|
switch (deny_current_branch) {
|
|
case DENY_IGNORE:
|
|
break;
|
|
case DENY_WARN:
|
|
if (!is_ref_checked_out(name))
|
|
break;
|
|
warning("updating the currently checked out branch; this may"
|
|
" cause confusion,\n"
|
|
"as the index and working tree do not reflect changes"
|
|
" that are now in HEAD.");
|
|
break;
|
|
case DENY_REFUSE:
|
|
if (!is_ref_checked_out(name))
|
|
break;
|
|
error("refusing to update checked out branch: %s", name);
|
|
return "branch is currently checked out";
|
|
}
|
|
|
|
if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
|
|
error("unpack should have generated %s, "
|
|
"but I can't find it!", sha1_to_hex(new_sha1));
|
|
return "bad pack";
|
|
}
|
|
if (deny_deletes && is_null_sha1(new_sha1) &&
|
|
!is_null_sha1(old_sha1) &&
|
|
!prefixcmp(name, "refs/heads/")) {
|
|
error("denying ref deletion for %s", name);
|
|
return "deletion prohibited";
|
|
}
|
|
if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
|
|
!is_null_sha1(old_sha1) &&
|
|
!prefixcmp(name, "refs/heads/")) {
|
|
struct object *old_object, *new_object;
|
|
struct commit *old_commit, *new_commit;
|
|
struct commit_list *bases, *ent;
|
|
|
|
old_object = parse_object(old_sha1);
|
|
new_object = parse_object(new_sha1);
|
|
|
|
if (!old_object || !new_object ||
|
|
old_object->type != OBJ_COMMIT ||
|
|
new_object->type != OBJ_COMMIT) {
|
|
error("bad sha1 objects for %s", name);
|
|
return "bad ref";
|
|
}
|
|
old_commit = (struct commit *)old_object;
|
|
new_commit = (struct commit *)new_object;
|
|
bases = get_merge_bases(old_commit, new_commit, 1);
|
|
for (ent = bases; ent; ent = ent->next)
|
|
if (!hashcmp(old_sha1, ent->item->object.sha1))
|
|
break;
|
|
free_commit_list(bases);
|
|
if (!ent) {
|
|
error("denying non-fast forward %s"
|
|
" (you should pull first)", name);
|
|
return "non-fast forward";
|
|
}
|
|
}
|
|
if (run_update_hook(cmd)) {
|
|
error("hook declined to update %s", name);
|
|
return "hook declined";
|
|
}
|
|
|
|
if (is_null_sha1(new_sha1)) {
|
|
if (!parse_object(old_sha1)) {
|
|
warning ("Allowing deletion of corrupt ref.");
|
|
old_sha1 = NULL;
|
|
}
|
|
if (delete_ref(name, old_sha1, 0)) {
|
|
error("failed to delete %s", name);
|
|
return "failed to delete";
|
|
}
|
|
return NULL; /* good */
|
|
}
|
|
else {
|
|
lock = lock_any_ref_for_update(name, old_sha1, 0);
|
|
if (!lock) {
|
|
error("failed to lock %s", name);
|
|
return "failed to lock";
|
|
}
|
|
if (write_ref_sha1(lock, new_sha1, "push")) {
|
|
return "failed to write"; /* error() already called */
|
|
}
|
|
return NULL; /* good */
|
|
}
|
|
}
|
|
|
|
static char update_post_hook[] = "hooks/post-update";
|
|
|
|
static void run_update_post_hook(struct command *cmd)
|
|
{
|
|
struct command *cmd_p;
|
|
int argc;
|
|
const char **argv;
|
|
|
|
for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
|
|
if (cmd_p->error_string)
|
|
continue;
|
|
argc++;
|
|
}
|
|
if (!argc || access(update_post_hook, X_OK) < 0)
|
|
return;
|
|
argv = xmalloc(sizeof(*argv) * (2 + argc));
|
|
argv[0] = update_post_hook;
|
|
|
|
for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
|
|
char *p;
|
|
if (cmd_p->error_string)
|
|
continue;
|
|
p = xmalloc(strlen(cmd_p->ref_name) + 1);
|
|
strcpy(p, cmd_p->ref_name);
|
|
argv[argc] = p;
|
|
argc++;
|
|
}
|
|
argv[argc] = NULL;
|
|
run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
|
|
| RUN_COMMAND_STDOUT_TO_STDERR);
|
|
}
|
|
|
|
static void execute_commands(const char *unpacker_error)
|
|
{
|
|
struct command *cmd = commands;
|
|
|
|
if (unpacker_error) {
|
|
while (cmd) {
|
|
cmd->error_string = "n/a (unpacker error)";
|
|
cmd = cmd->next;
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (run_hook(pre_receive_hook)) {
|
|
while (cmd) {
|
|
cmd->error_string = "pre-receive hook declined";
|
|
cmd = cmd->next;
|
|
}
|
|
return;
|
|
}
|
|
|
|
while (cmd) {
|
|
cmd->error_string = update(cmd);
|
|
cmd = cmd->next;
|
|
}
|
|
}
|
|
|
|
static void read_head_info(void)
|
|
{
|
|
struct command **p = &commands;
|
|
for (;;) {
|
|
static char line[1000];
|
|
unsigned char old_sha1[20], new_sha1[20];
|
|
struct command *cmd;
|
|
char *refname;
|
|
int len, reflen;
|
|
|
|
len = packet_read_line(0, line, sizeof(line));
|
|
if (!len)
|
|
break;
|
|
if (line[len-1] == '\n')
|
|
line[--len] = 0;
|
|
if (len < 83 ||
|
|
line[40] != ' ' ||
|
|
line[81] != ' ' ||
|
|
get_sha1_hex(line, old_sha1) ||
|
|
get_sha1_hex(line + 41, new_sha1))
|
|
die("protocol error: expected old/new/ref, got '%s'",
|
|
line);
|
|
|
|
refname = line + 82;
|
|
reflen = strlen(refname);
|
|
if (reflen + 82 < len) {
|
|
if (strstr(refname + reflen + 1, "report-status"))
|
|
report_status = 1;
|
|
}
|
|
cmd = xmalloc(sizeof(struct command) + len - 80);
|
|
hashcpy(cmd->old_sha1, old_sha1);
|
|
hashcpy(cmd->new_sha1, new_sha1);
|
|
memcpy(cmd->ref_name, line + 82, len - 81);
|
|
cmd->error_string = NULL;
|
|
cmd->next = NULL;
|
|
*p = cmd;
|
|
p = &cmd->next;
|
|
}
|
|
}
|
|
|
|
static const char *parse_pack_header(struct pack_header *hdr)
|
|
{
|
|
switch (read_pack_header(0, hdr)) {
|
|
case PH_ERROR_EOF:
|
|
return "eof before pack header was fully read";
|
|
|
|
case PH_ERROR_PACK_SIGNATURE:
|
|
return "protocol error (pack signature mismatch detected)";
|
|
|
|
case PH_ERROR_PROTOCOL:
|
|
return "protocol error (pack version unsupported)";
|
|
|
|
default:
|
|
return "unknown error in parse_pack_header";
|
|
|
|
case 0:
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
static const char *pack_lockfile;
|
|
|
|
static const char *unpack(void)
|
|
{
|
|
struct pack_header hdr;
|
|
const char *hdr_err;
|
|
char hdr_arg[38];
|
|
|
|
hdr_err = parse_pack_header(&hdr);
|
|
if (hdr_err)
|
|
return hdr_err;
|
|
snprintf(hdr_arg, sizeof(hdr_arg),
|
|
"--pack_header=%"PRIu32",%"PRIu32,
|
|
ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
|
|
|
|
if (ntohl(hdr.hdr_entries) < unpack_limit) {
|
|
int code, i = 0;
|
|
const char *unpacker[4];
|
|
unpacker[i++] = "unpack-objects";
|
|
if (receive_fsck_objects)
|
|
unpacker[i++] = "--strict";
|
|
unpacker[i++] = hdr_arg;
|
|
unpacker[i++] = NULL;
|
|
code = run_command_v_opt(unpacker, RUN_GIT_CMD);
|
|
switch (code) {
|
|
case 0:
|
|
return NULL;
|
|
case -ERR_RUN_COMMAND_FORK:
|
|
return "unpack fork failed";
|
|
case -ERR_RUN_COMMAND_EXEC:
|
|
return "unpack execute failed";
|
|
case -ERR_RUN_COMMAND_WAITPID:
|
|
return "waitpid failed";
|
|
case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
|
|
return "waitpid is confused";
|
|
case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
|
|
return "unpacker died of signal";
|
|
case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
|
|
return "unpacker died strangely";
|
|
default:
|
|
return "unpacker exited with error code";
|
|
}
|
|
} else {
|
|
const char *keeper[7];
|
|
int s, status, i = 0;
|
|
char keep_arg[256];
|
|
struct child_process ip;
|
|
|
|
s = sprintf(keep_arg, "--keep=receive-pack %"PRIuMAX" on ", (uintmax_t) getpid());
|
|
if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
|
|
strcpy(keep_arg + s, "localhost");
|
|
|
|
keeper[i++] = "index-pack";
|
|
keeper[i++] = "--stdin";
|
|
if (receive_fsck_objects)
|
|
keeper[i++] = "--strict";
|
|
keeper[i++] = "--fix-thin";
|
|
keeper[i++] = hdr_arg;
|
|
keeper[i++] = keep_arg;
|
|
keeper[i++] = NULL;
|
|
memset(&ip, 0, sizeof(ip));
|
|
ip.argv = keeper;
|
|
ip.out = -1;
|
|
ip.git_cmd = 1;
|
|
if (start_command(&ip))
|
|
return "index-pack fork failed";
|
|
pack_lockfile = index_pack_lockfile(ip.out);
|
|
close(ip.out);
|
|
status = finish_command(&ip);
|
|
if (!status) {
|
|
reprepare_packed_git();
|
|
return NULL;
|
|
}
|
|
return "index-pack abnormal exit";
|
|
}
|
|
}
|
|
|
|
static void report(const char *unpack_status)
|
|
{
|
|
struct command *cmd;
|
|
packet_write(1, "unpack %s\n",
|
|
unpack_status ? unpack_status : "ok");
|
|
for (cmd = commands; cmd; cmd = cmd->next) {
|
|
if (!cmd->error_string)
|
|
packet_write(1, "ok %s\n",
|
|
cmd->ref_name);
|
|
else
|
|
packet_write(1, "ng %s %s\n",
|
|
cmd->ref_name, cmd->error_string);
|
|
}
|
|
packet_flush(1);
|
|
}
|
|
|
|
static int delete_only(struct command *cmd)
|
|
{
|
|
while (cmd) {
|
|
if (!is_null_sha1(cmd->new_sha1))
|
|
return 0;
|
|
cmd = cmd->next;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int add_refs_from_alternate(struct alternate_object_database *e, void *unused)
|
|
{
|
|
char *other;
|
|
size_t len;
|
|
struct remote *remote;
|
|
struct transport *transport;
|
|
const struct ref *extra;
|
|
|
|
e->name[-1] = '\0';
|
|
other = xstrdup(make_absolute_path(e->base));
|
|
e->name[-1] = '/';
|
|
len = strlen(other);
|
|
|
|
while (other[len-1] == '/')
|
|
other[--len] = '\0';
|
|
if (len < 8 || memcmp(other + len - 8, "/objects", 8))
|
|
return 0;
|
|
/* Is this a git repository with refs? */
|
|
memcpy(other + len - 8, "/refs", 6);
|
|
if (!is_directory(other))
|
|
return 0;
|
|
other[len - 8] = '\0';
|
|
remote = remote_get(other);
|
|
transport = transport_get(remote, other);
|
|
for (extra = transport_get_remote_refs(transport);
|
|
extra;
|
|
extra = extra->next) {
|
|
add_extra_ref(".have", extra->old_sha1, 0);
|
|
}
|
|
transport_disconnect(transport);
|
|
free(other);
|
|
return 0;
|
|
}
|
|
|
|
static void add_alternate_refs(void)
|
|
{
|
|
foreach_alt_odb(add_refs_from_alternate, NULL);
|
|
}
|
|
|
|
int cmd_receive_pack(int argc, const char **argv, const char *prefix)
|
|
{
|
|
int i;
|
|
char *dir = NULL;
|
|
|
|
argv++;
|
|
for (i = 1; i < argc; i++) {
|
|
const char *arg = *argv++;
|
|
|
|
if (*arg == '-') {
|
|
/* Do flag handling here */
|
|
usage(receive_pack_usage);
|
|
}
|
|
if (dir)
|
|
usage(receive_pack_usage);
|
|
dir = xstrdup(arg);
|
|
}
|
|
if (!dir)
|
|
usage(receive_pack_usage);
|
|
|
|
setup_path();
|
|
|
|
if (!enter_repo(dir, 0))
|
|
die("'%s': unable to chdir or not a git archive", dir);
|
|
|
|
if (is_repository_shallow())
|
|
die("attempt to push into a shallow repository");
|
|
|
|
git_config(receive_pack_config, NULL);
|
|
|
|
if (0 <= transfer_unpack_limit)
|
|
unpack_limit = transfer_unpack_limit;
|
|
else if (0 <= receive_unpack_limit)
|
|
unpack_limit = receive_unpack_limit;
|
|
|
|
add_alternate_refs();
|
|
write_head_info();
|
|
clear_extra_refs();
|
|
|
|
/* EOF */
|
|
packet_flush(1);
|
|
|
|
read_head_info();
|
|
if (commands) {
|
|
const char *unpack_status = NULL;
|
|
|
|
if (!delete_only(commands))
|
|
unpack_status = unpack();
|
|
execute_commands(unpack_status);
|
|
if (pack_lockfile)
|
|
unlink(pack_lockfile);
|
|
if (report_status)
|
|
report(unpack_status);
|
|
run_hook(post_receive_hook);
|
|
run_update_post_hook(commands);
|
|
}
|
|
return 0;
|
|
}
|