#include "cache.h"
#include "config.h"
#include "pkt-line.h"
#include "run-command.h"
#include "strbuf.h"
#include "string-list.h"
#ifdef NO_INITGROUPS
#define initgroups(x, y) (0) /* nothing */
#endif
static enum log_destination {
LOG_DESTINATION_UNSET = -1,
LOG_DESTINATION_NONE = 0,
LOG_DESTINATION_STDERR = 1,
LOG_DESTINATION_SYSLOG = 2,
} log_destination = LOG_DESTINATION_UNSET;
static int verbose;
static int reuseaddr;
static int informative_errors;
static const char daemon_usage[] =
"git daemon [--verbose] [--syslog] [--export-all]\n"
" [--timeout=<n>] [--init-timeout=<n>] [--max-connections=<n>]\n"
" [--strict-paths] [--base-path=<path>] [--base-path-relaxed]\n"
" [--user-path | --user-path=<path>]\n"
" [--interpolated-path=<path>]\n"
" [--reuseaddr] [--pid-file=<file>]\n"
" [--(enable|disable|allow-override|forbid-override)=<service>]\n"
" [--access-hook=<path>]\n"
" [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n"
" [--detach] [--user=<user> [--group=<group>]]\n"
" [--log-destination=(stderr|syslog|none)]\n"
" [<directory>...]";
/* List of acceptable pathname prefixes */
static const char **ok_paths;
static int strict_paths;
/* If this is set, git-daemon-export-ok is not required */
static int export_all_trees;
/* Take all paths relative to this one if non-NULL */
static const char *base_path;
static const char *interpolated_path;
static int base_path_relaxed;
/* If defined, ~user notation is allowed and the string is inserted
* after ~user/. E.g. a request to git://host/~alice/frotz would
* go to /home/alice/pub_git/frotz with --user-path=pub_git.
*/
static const char *user_path;
/* Timeout, and initial timeout */
static unsigned int timeout;
static unsigned int init_timeout;
struct hostinfo {
struct strbuf hostname;
struct strbuf canon_hostname;
struct strbuf ip_address;
struct strbuf tcp_port;
unsigned int hostname_lookup_done:1;
unsigned int saw_extended_args:1;
};
static void lookup_hostname(struct hostinfo *hi);
static const char *get_canon_hostname(struct hostinfo *hi)
{
lookup_hostname(hi);
return hi->canon_hostname.buf;
}
static const char *get_ip_address(struct hostinfo *hi)
{
lookup_hostname(hi);
return hi->ip_address.buf;
}
static void logreport(int priority, const char *err, va_list params)
{
switch (log_destination) {
case LOG_DESTINATION_SYSLOG: {
char buf[1024];
vsnprintf(buf, sizeof(buf), err, params);
syslog(priority, "%s", buf);
break;
}
case LOG_DESTINATION_STDERR:
/*
* Since stderr is set to buffered mode, the
* logging of different processes will not overlap
* unless they overflow the (rather big) buffers.
*/
fprintf(stderr, "[%"PRIuMAX"] ", (uintmax_t)getpid());
vfprintf(stderr, err, params);
fputc('\n', stderr);
fflush(stderr);
break;
case LOG_DESTINATION_NONE:
break;
case LOG_DESTINATION_UNSET:
BUG("log destination not initialized correctly");
}
}
__attribute__((format (printf, 1, 2)))
static void logerror(const char *err, ...)
{
va_list params;
va_start(params, err);
logreport(LOG_ERR, err, params);
va_end(params);
}
__attribute__((format (printf, 1, 2)))
static void loginfo(const char *err, ...)
{
va_list params;
if (!verbose)
return;
va_start(params, err);
logreport(LOG_INFO, err, params);
va_end(params);
}
static void NORETURN daemon_die(const char *err, va_list params)
{
logreport(LOG_ERR, err, params);
exit(1);
}
struct expand_path_context {
const char *directory;
struct hostinfo *hostinfo;
};
static size_t expand_path(struct strbuf *sb, const char *placeholder, void *ctx)
{
struct expand_path_context *context = ctx;
struct hostinfo *hi = context->hostinfo;
switch (placeholder[0]) {
case 'H':
strbuf_addbuf(sb, &hi->hostname);
return 1;
case 'C':
if (placeholder[1] == 'H') {
strbuf_addstr(sb, get_canon_hostname(hi));
return 2;
}
break;
case 'I':
if (placeholder[1] == 'P') {
strbuf_addstr(sb, get_ip_address(hi));
return 2;
}
break;
case 'P':
strbuf_addbuf(sb, &hi->tcp_port);
return 1;
case 'D':
strbuf_addstr(sb, context->directory);
return 1;
}
return 0;
}
static const char *path_ok(const char *directory, struct hostinfo *hi)
{
static char rpath[PATH_MAX];
static char interp_path[PATH_MAX];
size_t rlen;
const char *path;
const char *dir;
dir = directory;
if (daemon_avoid_alias(dir)) {
logerror("'%s': aliased", dir);
return NULL;
}
if (*dir == '~') {
if (!user_path) {
logerror("'%s': User-path not allowed", dir);
return NULL;
}
if (*user_path) {
/* Got either "~alice" or "~alice/foo";
* rewrite them to "~alice/%s" or
* "~alice/%s/foo".
*/
int namlen, restlen = strlen(dir);
const char *slash = strchr(dir, '/');
if (!slash)
slash = dir + restlen;
namlen = slash - dir;
restlen -= namlen;
loginfo("userpath <%s>, request <%s>, namlen %d, restlen %d, slash <%s>", user_path, dir, namlen, restlen, slash);
rlen = snprintf(rpath, sizeof(rpath), "%.*s/%s%.*s",
namlen, dir, user_path, restlen, slash);
if (rlen >= sizeof(rpath)) {
logerror("user-path too large: %s", rpath);
return NULL;
}
dir = rpath;
}
}
else if (interpolated_path && hi->saw_extended_args) {
struct strbuf expanded_path = STRBUF_INIT;
struct expand_path_context context;
context.directory = directory;
context.hostinfo = hi;
if (*dir != '/') {
/* Allow only absolute */
logerror("'%s': Non-absolute path denied (interpolated-path active)", dir);
return NULL;
}
strbuf_expand(&expanded_path, interpolated_path,
expand_path, &context);
rlen = strlcpy(interp_path, expanded_path.buf,
sizeof(interp_path));
if (rlen >= sizeof(interp_path)) {
logerror("interpolated path too large: %s",
interp_path);
return NULL;
}
strbuf_release(&expanded_path);
loginfo("Interpolated dir '%s'", interp_path);
dir = interp_path;
}
else if (base_path) {
if (*dir != '/') {
/* Allow only absolute */
logerror("'%s': Non-absolute path denied (base-path active)", dir);
return NULL;
}
rlen = snprintf(rpath, sizeof(rpath), "%s%s", base_path, dir);
if (rlen >= sizeof(rpath)) {
logerror("base-path too large: %s", rpath);
return NULL;
}
dir = rpath;
}
path = enter_repo(dir, strict_paths);
if (!path && base_path && base_path_relaxed) {
/*
* if we fail and base_path_relaxed is enabled, try without
* prefixing the base path
*/
dir = directory;
path = enter_repo(dir, strict_paths);
}
if (!path) {
logerror("'%s' does not appear to be a git repository", dir);
return NULL;
}
if ( ok_paths && *ok_paths ) {
const char **pp;
int pathlen = strlen(path);
/* The validation is done on the paths after enter_repo
* appends optional {.git,.git/.git} and friends, but
* it does not use getcwd(). So if your /pub is
* a symlink to /mnt/pub, you can whitelist /pub and
* do not have to say /mnt/pub.
* Do not say /pub/.
*/
for ( pp = ok_paths ; *pp ; pp++ ) {
int len = strlen(*pp);
if (len <= pathlen &&
!memcmp(*pp, path, len) &&
(path[len] == '\0' ||
(!strict_paths && path[len] == '/')))
return path;
}
}
else {
/* be backwards compatible */
if (!strict_paths)
return path;
}
logerror("'%s': not in whitelist", path);
return NULL; /* Fallthrough. Deny by default */
}
typedef int (*daemon_service_fn)(const struct argv_array *env);
struct daemon_service {
const char *name;
const char *config_name;
daemon_service_fn fn;
int enabled;
int overridable;
};
static int daemon_error(const char *dir, const char *msg)
{
if (!informative_errors)
msg = "access denied or repository not exported";
packet_write_fmt(1, "ERR %s: %s", msg, dir);
return -1;
}
static const char *access_hook;
static int run_access_hook(struct daemon_service *service, const char *dir,
const char *path, struct hostinfo *hi)
{
struct child_process child = CHILD_PROCESS_INIT;
struct strbuf buf = STRBUF_INIT;
const char *argv[8];
const char **arg = argv;
char *eol;
int seen_errors = 0;
*arg++ = access_hook;
*arg++ = service->name;
*arg++ = path;
*arg++ = hi->hostname.buf;
*arg++ = get_canon_hostname(hi);
*arg++ = get_ip_address(hi);
*arg++ = hi->tcp_port.buf;
*arg = NULL;
child.use_shell = 1;
child.argv = argv;
child.no_stdin = 1;
child.no_stderr = 1;
child.out = -1;
if (start_command(&child)) {
logerror("daemon access hook '%s' failed to start",
access_hook);
goto error_return;
}
if (strbuf_read(&buf, child.out, 0) < 0) {
logerror("failed to read from pipe to daemon access hook '%s'",
access_hook);
strbuf_reset(&buf);
seen_errors = 1;
}
if (close(child.out) < 0) {
logerror("failed to close pipe to daemon access hook '%s'",
access_hook);
seen_errors = 1;
}
if (finish_command(&child))
seen_errors = 1;
if (!seen_errors) {
strbuf_release(&buf);
return 0;
}
error_return:
strbuf_ltrim(&buf);
if (!buf.len)
strbuf_addstr(&buf, "service rejected");
eol = strchr(buf.buf, '\n');
if (eol)
*eol = '\0';
errno = EACCES;
daemon_error(dir, buf.buf);
strbuf_release(&buf);
return -1;
}
static int run_service(const char *dir, struct daemon_service *service,
struct hostinfo *hi, const struct argv_array *env)
{
const char *path;
int enabled = service->enabled;
struct strbuf var = STRBUF_INIT;
loginfo("Request %s for '%s'", service->name, dir);
if (!enabled && !service->overridable) {
logerror("'%s': service not enabled.", service->name);
errno = EACCES;
return daemon_error(dir, "service not enabled");
}
if (!(path = path_ok(dir, hi)))
return daemon_error(dir, "no such repository");
/*
* Security on the cheap.
*
* We want a readable HEAD, usable "objects" directory, and
* a "git-daemon-export-ok" flag that says that the other side
* is ok with us doing this.
*
* path_ok() uses enter_repo() and does whitelist checking.
* We only need to make sure the repository is exported.
*/
if (!export_all_trees && access("git-daemon-export-ok", F_OK)) {
logerror("'%s': repository not exported.", path);
errno = EACCES;
return daemon_error(dir, "repository not exported");
}
if (service->overridable) {
strbuf_addf(&var, "daemon.%s", service->config_name);
git_config_get_bool(var.buf, &enabled);
strbuf_release(&var);
}
if (!enabled) {
logerror("'%s': service not enabled for '%s'",
service->name, path);
errno = EACCES;
return daemon_error(dir, "service not enabled");
}
/*
* Optionally, a hook can choose to deny access to the
* repository depending on the phase of the moon.
*/
if (access_hook && run_access_hook(service, dir, path, hi))
return -1;
/*
* We'll ignore SIGTERM from now on, we have a
* good client.
*/
signal(SIGTERM, SIG_IGN);
return service->fn(env);
}
static void copy_to_log(int fd)
{
struct strbuf line = STRBUF_INIT;
FILE *fp;
fp = fdopen(fd, "r");
if (fp == NULL) {
logerror("fdopen of error channel failed");
close(fd);
return;
}
while (strbuf_getline_lf(&line, fp) != EOF) {
logerror("%s", line.buf);
strbuf_setlen(&line, 0);
}
strbuf_release(&line);
fclose(fp);
}
static int run_service_command(struct child_process *cld)
{
argv_array_push(&cld->args, ".");
cld->git_cmd = 1;
cld->err = -1;
if (start_command(cld))
return -1;
close(0);
close(1);
copy_to_log(cld->err);
return finish_command(cld);
}
static int upload_pack(const struct argv_array *env)
{
struct child_process cld = CHILD_PROCESS_INIT;
argv_array_pushl(&cld.args, "upload-pack", "--strict", NULL);
argv_array_pushf(&cld.args, "--timeout=%u", timeout);
argv_array_pushv(&cld.env_array, env->argv);
return run_service_command(&cld);
}
static int upload_archive(const struct argv_array *env)
{
struct child_process cld = CHILD_PROCESS_INIT;
argv_array_push(&cld.args, "upload-archive");
argv_array_pushv(&cld.env_array, env->argv);
return run_service_command(&cld);
}
static int receive_pack(const struct argv_array *env)
{
struct child_process cld = CHILD_PROCESS_INIT;
argv_array_push(&cld.args, "receive-pack");
argv_array_pushv(&cld.env_array, env->argv);
return run_service_command(&cld);
}
static struct daemon_service daemon_service[] = {
{ "upload-archive", "uploadarch", upload_archive, 0, 1 },
{ "upload-pack", "uploadpack", upload_pack, 1, 1 },
{ "receive-pack", "receivepack", receive_pack, 0, 1 },
};
static void enable_service(const char *name, int ena)
{
int i;
for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
if (!strcmp(daemon_service[i].name, name)) {
daemon_service[i].enabled = ena;
return;
}
}
die("No such service %s", name);
}
static void make_service_overridable(const char *name, int ena)
{
int i;
for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
if (!strcmp(daemon_service[i].name, name)) {
daemon_service[i].overridable = ena;
return;
}
}
die("No such service %s", name);
}
static void parse_host_and_port(char *hostport, char **host,
char **port)
{
if (*hostport == '[') {
char *end;
end = strchr(hostport, ']');
if (!end)
die("Invalid request ('[' without ']')");
*end = '\0';
*host = hostport + 1;
if (!end[1])
*port = NULL;
else if (end[1] == ':')
*port = end + 2;
else
die("Garbage after end of host part");
} else {
*host = hostport;
*port = strrchr(hostport, ':');
if (*port) {
**port = '\0';
++*port;
}
}
}
/*
* Sanitize a string from the client so that it's OK to be inserted into a
* filesystem path. Specifically, we disallow slashes, runs of "..", and
* trailing and leading dots, which means that the client cannot escape
* our base path via ".." traversal.
*/
static void sanitize_client(struct strbuf *out, const char *in)
{
for (; *in; in++) {
if (*in == '/')
continue;
if (*in == '.' && (!out->len || out->buf[out->len - 1] == '.'))
continue;
strbuf_addch(out, *in);
}
while (out->len && out->buf[out->len - 1] == '.')
strbuf_setlen(out, out->len - 1);
}
/*
* Like sanitize_client, but we also perform any canonicalization
* to make life easier on the admin.
*/
static void canonicalize_client(struct strbuf *out, const char *in)
{
sanitize_client(out, in);
strbuf_tolower(out);
}
/*
* Read the host as supplied by the client connection.
*
* Returns a pointer to the character after the NUL byte terminating the host
* argument, or 'extra_args' if there is no host argument.
*/
static char *parse_host_arg(struct hostinfo *hi, char *extra_args, int buflen)
{
char *val;
int vallen;
char *end = extra_args + buflen;
if (extra_args < end && *extra_args) {
hi->saw_extended_args = 1;
if (strncasecmp("host=", extra_args, 5) == 0) {
val = extra_args + 5;
vallen = strlen(val) + 1;
loginfo("Extended attribute \"host\": %s", val);
if (*val) {
/* Split <host>:<port> at colon. */
char *host;
char *port;
parse_host_and_port(val, &host, &port);
if (port)
sanitize_client(&hi->tcp_port, port);
canonicalize_client(&hi->hostname, host);
hi->hostname_lookup_done = 0;
}
/* On to the next one */
extra_args = val + vallen;
}
if (extra_args < end && *extra_args)
die("Invalid request");
}
return extra_args;
}
static void parse_extra_args(struct hostinfo *hi, struct argv_array *env,
char *extra_args, int buflen)
{
const char *end = extra_args + buflen;
struct strbuf git_protocol = STRBUF_INIT;
/* First look for the host argument */
extra_args = parse_host_arg(hi, extra_args, buflen);
/* Look for additional arguments places after a second NUL byte */
for (; extra_args < end; extra_args += strlen(extra_args) + 1) {
const char *arg = extra_args;
/*
* Parse the extra arguments, adding most to 'git_protocol'
* which will be used to set the 'GIT_PROTOCOL' envvar in the
* service that will be run.
*
* If there ends up being a particular arg in the future that
* git-daemon needs to parse specifically (like the 'host' arg)
* then it can be parsed here and not added to 'git_protocol'.
*/
if (*arg) {
if (git_protocol.len > 0)
strbuf_addch(&git_protocol, ':');
strbuf_addstr(&git_protocol, arg);
}
}
if (git_protocol.len > 0) {
loginfo("Extended attribute \"protocol\": %s", git_protocol.buf);
argv_array_pushf(env, GIT_PROTOCOL_ENVIRONMENT "=%s",
git_protocol.buf);
}
strbuf_release(&git_protocol);
}
/*
* Locate canonical hostname and its IP address.
*/
static void lookup_hostname(struct hostinfo *hi)
{
if (!hi->hostname_lookup_done && hi->hostname.len) {
#ifndef NO_IPV6
struct addrinfo hints;
struct addrinfo *ai;
int gai;
static char addrbuf[HOST_NAME_MAX + 1];
memset(&hints, 0, sizeof(hints));
hints.ai_flags = AI_CANONNAME;
gai = getaddrinfo(hi->hostname.buf, NULL, &hints, &ai);
if (!gai) {
struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
inet_ntop(AF_INET, &sin_addr->sin_addr,
addrbuf, sizeof(addrbuf));
strbuf_addstr(&hi->ip_address, addrbuf);
if (ai->ai_canonname)
sanitize_client(&hi->canon_hostname,
ai->ai_canonname);
else
strbuf_addbuf(&hi->canon_hostname,
&hi->ip_address);
freeaddrinfo(ai);
}
#else
struct hostent *hent;
struct sockaddr_in sa;
char **ap;
static char addrbuf[HOST_NAME_MAX + 1];
hent = gethostbyname(hi->hostname.buf);
if (hent) {
ap = hent->h_addr_list;
memset(&sa, 0, sizeof sa);
sa.sin_family = hent->h_addrtype;
sa.sin_port = htons(0);
memcpy(&sa.sin_addr, *ap, hent->h_length);
inet_ntop(hent->h_addrtype, &sa.sin_addr,
addrbuf, sizeof(addrbuf));
sanitize_client(&hi->canon_hostname, hent->h_name);
strbuf_addstr(&hi->ip_address, addrbuf);
}
#endif
hi->hostname_lookup_done = 1;
}
}
static void hostinfo_init(struct hostinfo *hi)
{
memset(hi, 0, sizeof(*hi));
strbuf_init(&hi->hostname, 0);
strbuf_init(&hi->canon_hostname, 0);
strbuf_init(&hi->ip_address, 0);
strbuf_init(&hi->tcp_port, 0);
}
static void hostinfo_clear(struct hostinfo *hi)
{
strbuf_release(&hi->hostname);
strbuf_release(&hi->canon_hostname);
strbuf_release(&hi->ip_address);
strbuf_release(&hi->tcp_port);
}
static void set_keep_alive(int sockfd)
{
int ka = 1;
if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0) {
if (errno != ENOTSOCK)
logerror("unable to set SO_KEEPALIVE on socket: %s",
strerror(errno));
}
}
static int execute(void)
{
char *line = packet_buffer;
int pktlen, len, i;
char *addr = getenv("REMOTE_ADDR"), *port = getenv("REMOTE_PORT");
struct hostinfo hi;
struct argv_array env = ARGV_ARRAY_INIT;
hostinfo_init(&hi);
if (addr)
loginfo("Connection from %s:%s", addr, port);
set_keep_alive(0);
alarm(init_timeout ? init_timeout : timeout);
pktlen = packet_read(0, NULL, NULL, packet_buffer, sizeof(packet_buffer), 0);
alarm(0);
len = strlen(line);
if (len && line[len-1] == '\n')
line[len-1] = 0;
/* parse additional args hidden behind a NUL byte */
if (len != pktlen)
parse_extra_args(&hi, &env, line + len + 1, pktlen - len - 1);
for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
struct daemon_service *s = &(daemon_service[i]);
const char *arg;
if (skip_prefix(line, "git-", &arg) &&
skip_prefix(arg, s->name, &arg) &&
*arg++ == ' ') {
/*
* Note: The directory here is probably context sensitive,
* and might depend on the actual service being performed.
*/
int rc = run_service(arg, s, &hi, &env);
hostinfo_clear(&hi);
argv_array_clear(&env);
return rc;
}
}
hostinfo_clear(&hi);
argv_array_clear(&env);
logerror("Protocol error: '%s'", line);
return -1;
}
static int addrcmp(const struct sockaddr_storage *s1,
const struct sockaddr_storage *s2)
{
const struct sockaddr *sa1 = (const struct sockaddr*) s1;
const struct sockaddr *sa2 = (const struct sockaddr*) s2;
if (sa1->sa_family != sa2->sa_family)
return sa1->sa_family - sa2->sa_family;
if (sa1->sa_family == AF_INET)
return memcmp(&((struct sockaddr_in *)s1)->sin_addr,
&((struct sockaddr_in *)s2)->sin_addr,
sizeof(struct in_addr));
#ifndef NO_IPV6
if (sa1->sa_family == AF_INET6)
return memcmp(&((struct sockaddr_in6 *)s1)->sin6_addr,
&((struct sockaddr_in6 *)s2)->sin6_addr,
sizeof(struct in6_addr));
#endif
return 0;
}
static int max_connections = 32;
static unsigned int live_children;
static struct child {
struct child *next;
struct child_process cld;
struct sockaddr_storage address;
} *firstborn;
static void add_child(struct child_process *cld, struct sockaddr *addr, socklen_t addrlen)
{
struct child *newborn, **cradle;
newborn = xcalloc(1, sizeof(*newborn));
live_children++;
memcpy(&newborn->cld, cld, sizeof(*cld));
memcpy(&newborn->address, addr, addrlen);
for (cradle = &firstborn; *cradle; cradle = &(*cradle)->next)
if (!addrcmp(&(*cradle)->address, &newborn->address))
break;
newborn->next = *cradle;
*cradle = newborn;
}
/*
* This gets called if the number of connections grows
* past "max_connections".
*
* We kill the newest connection from a duplicate IP.
*/
static void kill_some_child(void)
{
const struct child *blanket, *next;
if (!(blanket = firstborn))
return;
for (; (next = blanket->next); blanket = next)
if (!addrcmp(&blanket->address, &next->address)) {
kill(blanket->cld.pid, SIGTERM);
break;
}
}
static void check_dead_children(void)
{
int status;
pid_t pid;
struct child **cradle, *blanket;
for (cradle = &firstborn; (blanket = *cradle);)
if ((pid = waitpid(blanket->cld.pid, &status, WNOHANG)) > 1) {
const char *dead = "";
if (status)
dead = " (with error)";
loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead);
/* remove the child */
*cradle = blanket->next;
live_children--;
child_process_clear(&blanket->cld);
free(blanket);
} else
cradle = &blanket->next;
}
static struct argv_array cld_argv = ARGV_ARRAY_INIT;
static void handle(int incoming, struct sockaddr *addr, socklen_t addrlen)
{
struct child_process cld = CHILD_PROCESS_INIT;
if (max_connections && live_children >= max_connections) {
kill_some_child();
sleep(1); /* give it some time to die */
check_dead_children();
if (live_children >= max_connections) {
close(incoming);
logerror("Too many children, dropping connection");
return;
}
}
if (addr->sa_family == AF_INET) {
char buf[128] = "";
struct sockaddr_in *sin_addr = (void *) addr;
inet_ntop(addr->sa_family, &sin_addr->sin_addr, buf, sizeof(buf));
argv_array_pushf(&cld.env_array, "REMOTE_ADDR=%s", buf);
argv_array_pushf(&cld.env_array, "REMOTE_PORT=%d",
ntohs(sin_addr->sin_port));
#ifndef NO_IPV6
} else if (addr->sa_family == AF_INET6) {
char buf[128] = "";
struct sockaddr_in6 *sin6_addr = (void *) addr;
inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, sizeof(buf));
argv_array_pushf(&cld.env_array, "REMOTE_ADDR=[%s]", buf);
argv_array_pushf(&cld.env_array, "REMOTE_PORT=%d",
ntohs(sin6_addr->sin6_port));
#endif
}
cld.argv = cld_argv.argv;
cld.in = incoming;
cld.out = dup(incoming);
if (start_command(&cld))
logerror("unable to fork");
else
add_child(&cld, addr, addrlen);
}
static void child_handler(int signo)
{
/*
* Otherwise empty handler because systemcalls will get interrupted
* upon signal receipt
* SysV needs the handler to be rearmed
*/
signal(SIGCHLD, child_handler);
}
static int set_reuse_addr(int sockfd)
{
int on = 1;
if (!reuseaddr)
return 0;
return setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
&on, sizeof(on));
}
struct socketlist {
int *list;
size_t nr;
size_t alloc;
};
static const char *ip2str(int family, struct sockaddr *sin, socklen_t len)
{
#ifdef NO_IPV6
static char ip[INET_ADDRSTRLEN];
#else
static char ip[INET6_ADDRSTRLEN];
#endif
switch (family) {
#ifndef NO_IPV6
case AF_INET6:
inet_ntop(family, &((struct sockaddr_in6*)sin)->sin6_addr, ip, len);
break;
#endif
case AF_INET:
inet_ntop(family, &((struct sockaddr_in*)sin)->sin_addr, ip, len);
break;
default:
xsnprintf(ip, sizeof(ip), "<unknown>");
}
return ip;
}
#ifndef NO_IPV6
static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
{
int socknum = 0;
char pbuf[NI_MAXSERV];
struct addrinfo hints, *ai0, *ai;
int gai;
long flags;
xsnprintf(pbuf, sizeof(pbuf), "%d", listen_port);
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
hints.ai_flags = AI_PASSIVE;
gai = getaddrinfo(listen_addr, pbuf, &hints, &ai0);
if (gai) {
logerror("getaddrinfo() for %s failed: %s", listen_addr, gai_strerror(gai));
return 0;
}
for (ai = ai0; ai; ai = ai->ai_next) {
int sockfd;
sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
if (sockfd < 0)
continue;
if (sockfd >= FD_SETSIZE) {
logerror("Socket descriptor too large");
close(sockfd);
continue;
}
#ifdef IPV6_V6ONLY
if (ai->ai_family == AF_INET6) {
int on = 1;
setsockopt(sockfd, IPPROTO_IPV6, IPV6_V6ONLY,
&on, sizeof(on));
/* Note: error is not fatal */
}
#endif
if (set_reuse_addr(sockfd)) {
logerror("Could not set SO_REUSEADDR: %s", strerror(errno));
close(sockfd);
continue;
}
set_keep_alive(sockfd);
if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
logerror("Could not bind to %s: %s",
ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
strerror(errno));
close(sockfd);
continue; /* not fatal */
}
if (listen(sockfd, 5) < 0) {
logerror("Could not listen to %s: %s",
ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
strerror(errno));
close(sockfd);
continue; /* not fatal */
}
flags = fcntl(sockfd, F_GETFD, 0);
if (flags >= 0)
fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc);
socklist->list[socklist->nr++] = sockfd;
socknum++;
}
freeaddrinfo(ai0);
return socknum;
}
#else /* NO_IPV6 */
static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
{
struct sockaddr_in sin;
int sockfd;
long flags;
memset(&sin, 0, sizeof sin);
sin.sin_family = AF_INET;
sin.sin_port = htons(listen_port);
if (listen_addr) {
/* Well, host better be an IP address here. */
if (inet_pton(AF_INET, listen_addr, &sin.sin_addr.s_addr) <= 0)
return 0;
} else {
sin.sin_addr.s_addr = htonl(INADDR_ANY);
}
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0)
return 0;
if (set_reuse_addr(sockfd)) {
logerror("Could not set SO_REUSEADDR: %s", strerror(errno));
close(sockfd);
return 0;
}
set_keep_alive(sockfd);
if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) {
logerror("Could not bind to %s: %s",
ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
strerror(errno));
close(sockfd);
return 0;
}
if (listen(sockfd, 5) < 0) {
logerror("Could not listen to %s: %s",
ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
strerror(errno));
close(sockfd);
return 0;
}
flags = fcntl(sockfd, F_GETFD, 0);
if (flags >= 0)
fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc);
socklist->list[socklist->nr++] = sockfd;
return 1;
}
#endif
static void socksetup(struct string_list *listen_addr, int listen_port, struct socketlist *socklist)
{
if (!listen_addr->nr)
setup_named_sock(NULL, listen_port, socklist);
else {
int i, socknum;
for (i = 0; i < listen_addr->nr; i++) {
socknum = setup_named_sock(listen_addr->items[i].string,
listen_port, socklist);
if (socknum == 0)
logerror("unable to allocate any listen sockets for host %s on port %u",
listen_addr->items[i].string, listen_port);
}
}
}
static int service_loop(struct socketlist *socklist)
{
struct pollfd *pfd;
int i;
pfd = xcalloc(socklist->nr, sizeof(struct pollfd));
for (i = 0; i < socklist->nr; i++) {
pfd[i].fd = socklist->list[i];
pfd[i].events = POLLIN;
}
signal(SIGCHLD, child_handler);
for (;;) {
int i;
check_dead_children();
if (poll(pfd, socklist->nr, -1) < 0) {
if (errno != EINTR) {
logerror("Poll failed, resuming: %s",
strerror(errno));
sleep(1);
}
continue;
}
for (i = 0; i < socklist->nr; i++) {
if (pfd[i].revents & POLLIN) {
union {
struct sockaddr sa;
struct sockaddr_in sai;
#ifndef NO_IPV6
struct sockaddr_in6 sai6;
#endif
} ss;
socklen_t sslen = sizeof(ss);
int incoming = accept(pfd[i].fd, &ss.sa, &sslen);
if (incoming < 0) {
switch (errno) {
case EAGAIN:
case EINTR:
case ECONNABORTED:
continue;
default:
die_errno("accept returned");
}
}
handle(incoming, &ss.sa, sslen);
}
}
}
}
#ifdef NO_POSIX_GOODIES
struct credentials;
static void drop_privileges(struct credentials *cred)
{
/* nothing */
}
static struct credentials *prepare_credentials(const char *user_name,
const char *group_name)
{
die("--user not supported on this platform");
}
#else
struct credentials {
struct passwd *pass;
gid_t gid;
};
static void drop_privileges(struct credentials *cred)
{
if (cred && (initgroups(cred->pass->pw_name, cred->gid) ||
setgid (cred->gid) || setuid(cred->pass->pw_uid)))
die("cannot drop privileges");
}
static struct credentials *prepare_credentials(const char *user_name,
const char *group_name)
{
static struct credentials c;
c.pass = getpwnam(user_name);
if (!c.pass)
die("user not found - %s", user_name);
if (!group_name)
c.gid = c.pass->pw_gid;
else {
struct group *group = getgrnam(group_name);
if (!group)
die("group not found - %s", group_name);
c.gid = group->gr_gid;
}
return &c;
}
#endif
static int serve(struct string_list *listen_addr, int listen_port,
struct credentials *cred)
{
struct socketlist socklist = { NULL, 0, 0 };
socksetup(listen_addr, listen_port, &socklist);
if (socklist.nr == 0)
die("unable to allocate any listen sockets on port %u",
listen_port);
drop_privileges(cred);
loginfo("Ready to rumble");
return service_loop(&socklist);
}
int cmd_main(int argc, const char **argv)
{
int listen_port = 0;
struct string_list listen_addr = STRING_LIST_INIT_NODUP;
int serve_mode = 0, inetd_mode = 0;
const char *pid_file = NULL, *user_name = NULL, *group_name = NULL;
int detach = 0;
struct credentials *cred = NULL;
int i;
for (i = 1; i < argc; i++) {
const char *arg = argv[i];
const char *v;
if (skip_prefix(arg, "--listen=", &v)) {
string_list_append(&listen_addr, xstrdup_tolower(v));
continue;
}
if (skip_prefix(arg, "--port=", &v)) {
char *end;
unsigned long n;
n = strtoul(v, &end, 0);
if (*v && !*end) {
listen_port = n;
continue;
}
}
if (!strcmp(arg, "--serve")) {
serve_mode = 1;
continue;
}
if (!strcmp(arg, "--inetd")) {
inetd_mode = 1;
continue;
}
if (!strcmp(arg, "--verbose")) {
verbose = 1;
continue;
}
if (!strcmp(arg, "--syslog")) {
log_destination = LOG_DESTINATION_SYSLOG;
continue;
}
if (skip_prefix(arg, "--log-destination=", &v)) {
if (!strcmp(v, "syslog")) {
log_destination = LOG_DESTINATION_SYSLOG;
continue;
} else if (!strcmp(v, "stderr")) {
log_destination = LOG_DESTINATION_STDERR;
continue;
} else if (!strcmp(v, "none")) {
log_destination = LOG_DESTINATION_NONE;
continue;
} else
die("unknown log destination '%s'", v);
}
if (!strcmp(arg, "--export-all")) {
export_all_trees = 1;
continue;
}
if (skip_prefix(arg, "--access-hook=", &v)) {
access_hook = v;
continue;
}
if (skip_prefix(arg, "--timeout=", &v)) {
timeout = atoi(v);
continue;
}
if (skip_prefix(arg, "--init-timeout=", &v)) {
init_timeout = atoi(v);
continue;
}
if (skip_prefix(arg, "--max-connections=", &v)) {
max_connections = atoi(v);
if (max_connections < 0)
max_connections = 0; /* unlimited */
continue;
}
if (!strcmp(arg, "--strict-paths")) {
strict_paths = 1;
continue;
}
if (skip_prefix(arg, "--base-path=", &v)) {
base_path = v;
continue;
}
if (!strcmp(arg, "--base-path-relaxed")) {
base_path_relaxed = 1;
continue;
}
if (skip_prefix(arg, "--interpolated-path=", &v)) {
interpolated_path = v;
continue;
}
if (!strcmp(arg, "--reuseaddr")) {
reuseaddr = 1;
continue;
}
if (!strcmp(arg, "--user-path")) {
user_path = "";
continue;
}
if (skip_prefix(arg, "--user-path=", &v)) {
user_path = v;
continue;
}
if (skip_prefix(arg, "--pid-file=", &v)) {
pid_file = v;
continue;
}
if (!strcmp(arg, "--detach")) {
detach = 1;
continue;
}
if (skip_prefix(arg, "--user=", &v)) {
user_name = v;
continue;
}
if (skip_prefix(arg, "--group=", &v)) {
group_name = v;
continue;
}
if (skip_prefix(arg, "--enable=", &v)) {
enable_service(v, 1);
continue;
}
if (skip_prefix(arg, "--disable=", &v)) {
enable_service(v, 0);
continue;
}
if (skip_prefix(arg, "--allow-override=", &v)) {
make_service_overridable(v, 1);
continue;
}
if (skip_prefix(arg, "--forbid-override=", &v)) {
make_service_overridable(v, 0);
continue;
}
if (!strcmp(arg, "--informative-errors")) {
informative_errors = 1;
continue;
}
if (!strcmp(arg, "--no-informative-errors")) {
informative_errors = 0;
continue;
}
if (!strcmp(arg, "--")) {
ok_paths = &argv[i+1];
break;
} else if (arg[0] != '-') {
ok_paths = &argv[i];
break;
}
usage(daemon_usage);
}
if (log_destination == LOG_DESTINATION_UNSET) {
if (inetd_mode || detach)
log_destination = LOG_DESTINATION_SYSLOG;
else
log_destination = LOG_DESTINATION_STDERR;
}
if (log_destination == LOG_DESTINATION_SYSLOG) {
openlog("git-daemon", LOG_PID, LOG_DAEMON);
set_die_routine(daemon_die);
} else
/* avoid splitting a message in the middle */
setvbuf(stderr, NULL, _IOFBF, 4096);
if (inetd_mode && (detach || group_name || user_name))
die("--detach, --user and --group are incompatible with --inetd");
if (inetd_mode && (listen_port || (listen_addr.nr > 0)))
die("--listen= and --port= are incompatible with --inetd");
else if (listen_port == 0)
listen_port = DEFAULT_GIT_PORT;
if (group_name && !user_name)
die("--group supplied without --user");
if (user_name)
cred = prepare_credentials(user_name, group_name);
if (strict_paths && (!ok_paths || !*ok_paths))
die("option --strict-paths requires a whitelist");
if (base_path && !is_directory(base_path))
die("base-path '%s' does not exist or is not a directory",
base_path);
if (log_destination != LOG_DESTINATION_STDERR) {
if (!freopen("/dev/null", "w", stderr))
die_errno("failed to redirect stderr to /dev/null");
}
if (inetd_mode || serve_mode)
return execute();
if (detach) {
if (daemonize())
die("--detach not supported on this platform");
}
if (pid_file)
write_file(pid_file, "%"PRIuMAX, (uintmax_t) getpid());
/* prepare argv for serving-processes */
argv_array_push(&cld_argv, argv[0]); /* git-daemon */
argv_array_push(&cld_argv, "--serve");
for (i = 1; i < argc; ++i)
argv_array_push(&cld_argv, argv[i]);
return serve(&listen_addr, listen_port, cred);
}
