git/daemon.c
Jonathan Nieder 081f84ee9e daemon: support <directory> arguments again
Ever since v1.7.4-rc0~125^2~8 (daemon: use run-command api for async
serving, 2010-11-04), git daemon spawns child processes instead of
forking to serve requests.  The child processes learn that they are
being run for this purpose from the presence of the --serve command
line flag.

When running with <ok_path> arguments, the --serve flag is treated
as one of the path arguments and the special child behavior does
not kick in.  So the child becomes an ordinary git daemon process,
notices that all the addresses it needs are in use, and exits with
the message "fatal: unable to allocate any listen sockets on port
9418".

Fix it by putting --serve at the beginning of the command line,
where the flag cannot be mistaken for a path argument.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Erik Faye-Lund <kusmabite@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-01-04 11:23:42 -08:00

1237 lines
28 KiB
C

#include "cache.h"
#include "pkt-line.h"
#include "exec_cmd.h"
#include "run-command.h"
#include "strbuf.h"
#include "string-list.h"
#ifndef HOST_NAME_MAX
#define HOST_NAME_MAX 256
#endif
#ifndef NI_MAXSERV
#define NI_MAXSERV 32
#endif
#ifdef NO_INITGROUPS
#define initgroups(x, y) (0) /* nothing */
#endif
static int log_syslog;
static int verbose;
static int reuseaddr;
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"
" [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n"
" [--detach] [--user=<user> [--group=<group>]]\n"
" [<directory>...]";
/* List of acceptable pathname prefixes */
static 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 char *base_path;
static char *interpolated_path;
static int base_path_relaxed;
/* Flag indicating client sent extra args. */
static int saw_extended_args;
/* 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;
static char *hostname;
static char *canon_hostname;
static char *ip_address;
static char *tcp_port;
static void logreport(int priority, const char *err, va_list params)
{
if (log_syslog) {
char buf[1024];
vsnprintf(buf, sizeof(buf), err, params);
syslog(priority, "%s", buf);
} else {
/*
* 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);
}
}
__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);
}
static char *path_ok(char *directory)
{
static char rpath[PATH_MAX];
static char interp_path[PATH_MAX];
char *path;
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);
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);
snprintf(rpath, PATH_MAX, "%.*s/%s%.*s",
namlen, dir, user_path, restlen, slash);
dir = rpath;
}
}
else if (interpolated_path && saw_extended_args) {
struct strbuf expanded_path = STRBUF_INIT;
struct strbuf_expand_dict_entry dict[6];
dict[0].placeholder = "H"; dict[0].value = hostname;
dict[1].placeholder = "CH"; dict[1].value = canon_hostname;
dict[2].placeholder = "IP"; dict[2].value = ip_address;
dict[3].placeholder = "P"; dict[3].value = tcp_port;
dict[4].placeholder = "D"; dict[4].value = directory;
dict[5].placeholder = NULL; dict[5].value = NULL;
if (*dir != '/') {
/* Allow only absolute */
logerror("'%s': Non-absolute path denied (interpolated-path active)", dir);
return NULL;
}
strbuf_expand(&expanded_path, interpolated_path,
strbuf_expand_dict_cb, &dict);
strlcpy(interp_path, expanded_path.buf, PATH_MAX);
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;
}
snprintf(rpath, PATH_MAX, "%s%s", base_path, dir);
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 ) {
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)(void);
struct daemon_service {
const char *name;
const char *config_name;
daemon_service_fn fn;
int enabled;
int overridable;
};
static struct daemon_service *service_looking_at;
static int service_enabled;
static int git_daemon_config(const char *var, const char *value, void *cb)
{
if (!prefixcmp(var, "daemon.") &&
!strcmp(var + 7, service_looking_at->config_name)) {
service_enabled = git_config_bool(var, value);
return 0;
}
/* we are not interested in parsing any other configuration here */
return 0;
}
static int run_service(char *dir, struct daemon_service *service)
{
const char *path;
int enabled = service->enabled;
loginfo("Request %s for '%s'", service->name, dir);
if (!enabled && !service->overridable) {
logerror("'%s': service not enabled.", service->name);
errno = EACCES;
return -1;
}
if (!(path = path_ok(dir)))
return -1;
/*
* 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 -1;
}
if (service->overridable) {
service_looking_at = service;
service_enabled = -1;
git_config(git_daemon_config, NULL);
if (0 <= service_enabled)
enabled = service_enabled;
}
if (!enabled) {
logerror("'%s': service not enabled for '%s'",
service->name, path);
errno = EACCES;
return -1;
}
/*
* We'll ignore SIGTERM from now on, we have a
* good client.
*/
signal(SIGTERM, SIG_IGN);
return service->fn();
}
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(&line, fp, '\n') != EOF) {
logerror("%s", line.buf);
strbuf_setlen(&line, 0);
}
strbuf_release(&line);
fclose(fp);
}
static int run_service_command(const char **argv)
{
struct child_process cld;
memset(&cld, 0, sizeof(cld));
cld.argv = argv;
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(void)
{
/* Timeout as string */
char timeout_buf[64];
const char *argv[] = { "upload-pack", "--strict", NULL, ".", NULL };
argv[2] = timeout_buf;
snprintf(timeout_buf, sizeof timeout_buf, "--timeout=%u", timeout);
return run_service_command(argv);
}
static int upload_archive(void)
{
static const char *argv[] = { "upload-archive", ".", NULL };
return run_service_command(argv);
}
static int receive_pack(void)
{
static const char *argv[] = { "receive-pack", ".", NULL };
return run_service_command(argv);
}
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 char *xstrdup_tolower(const char *str)
{
char *p, *dup = xstrdup(str);
for (p = dup; *p; p++)
*p = tolower(*p);
return dup;
}
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;
}
}
}
/*
* Read the host as supplied by the client connection.
*/
static void parse_host_arg(char *extra_args, int buflen)
{
char *val;
int vallen;
char *end = extra_args + buflen;
if (extra_args < end && *extra_args) {
saw_extended_args = 1;
if (strncasecmp("host=", extra_args, 5) == 0) {
val = extra_args + 5;
vallen = strlen(val) + 1;
if (*val) {
/* Split <host>:<port> at colon. */
char *host;
char *port;
parse_host_and_port(val, &host, &port);
if (port) {
free(tcp_port);
tcp_port = xstrdup(port);
}
free(hostname);
hostname = xstrdup_tolower(host);
}
/* On to the next one */
extra_args = val + vallen;
}
if (extra_args < end && *extra_args)
die("Invalid request");
}
/*
* Locate canonical hostname and its IP address.
*/
if (hostname) {
#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(hostname, 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));
free(ip_address);
ip_address = xstrdup(addrbuf);
free(canon_hostname);
canon_hostname = xstrdup(ai->ai_canonname ?
ai->ai_canonname : ip_address);
freeaddrinfo(ai);
}
#else
struct hostent *hent;
struct sockaddr_in sa;
char **ap;
static char addrbuf[HOST_NAME_MAX + 1];
hent = gethostbyname(hostname);
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));
free(canon_hostname);
canon_hostname = xstrdup(hent->h_name);
free(ip_address);
ip_address = xstrdup(addrbuf);
#endif
}
}
static int execute(void)
{
static char line[1000];
int pktlen, len, i;
char *addr = getenv("REMOTE_ADDR"), *port = getenv("REMOTE_PORT");
if (addr)
loginfo("Connection from %s:%s", addr, port);
alarm(init_timeout ? init_timeout : timeout);
pktlen = packet_read_line(0, line, sizeof(line));
alarm(0);
len = strlen(line);
if (pktlen != len)
loginfo("Extended attributes (%d bytes) exist <%.*s>",
(int) pktlen - len,
(int) pktlen - len, line + len + 1);
if (len && line[len-1] == '\n') {
line[--len] = 0;
pktlen--;
}
free(hostname);
free(canon_hostname);
free(ip_address);
free(tcp_port);
hostname = canon_hostname = ip_address = tcp_port = NULL;
if (len != pktlen)
parse_host_arg(line + len + 1, pktlen - len - 1);
for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
struct daemon_service *s = &(daemon_service[i]);
int namelen = strlen(s->name);
if (!prefixcmp(line, "git-") &&
!strncmp(s->name, line + 4, namelen) &&
line[namelen + 4] == ' ') {
/*
* Note: The directory here is probably context sensitive,
* and might depend on the actual service being performed.
*/
return run_service(line + namelen + 5, s);
}
}
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--;
free(blanket);
} else
cradle = &blanket->next;
}
static char **cld_argv;
static void handle(int incoming, struct sockaddr *addr, socklen_t addrlen)
{
struct child_process cld = { 0 };
char addrbuf[300] = "REMOTE_ADDR=", portbuf[300];
char *env[] = { addrbuf, portbuf, NULL };
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) {
struct sockaddr_in *sin_addr = (void *) addr;
inet_ntop(addr->sa_family, &sin_addr->sin_addr, addrbuf + 12,
sizeof(addrbuf) - 12);
snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d",
ntohs(sin_addr->sin_port));
#ifndef NO_IPV6
} else if (addr && addr->sa_family == AF_INET6) {
struct sockaddr_in6 *sin6_addr = (void *) addr;
char *buf = addrbuf + 12;
*buf++ = '['; *buf = '\0'; /* stpcpy() is cool */
inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf,
sizeof(addrbuf) - 13);
strcat(buf, "]");
snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d",
ntohs(sin6_addr->sin6_port));
#endif
}
cld.env = (const char **)env;
cld.argv = (const char **)cld_argv;
cld.in = incoming;
cld.out = dup(incoming);
if (start_command(&cld))
logerror("unable to fork");
else
add_child(&cld, addr, addrlen);
close(incoming);
}
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;
};
#ifndef NO_IPV6
static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
{
int socknum = 0;
int maxfd = -1;
char pbuf[NI_MAXSERV];
struct addrinfo hints, *ai0, *ai;
int gai;
long flags;
sprintf(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)) {
close(sockfd);
continue;
}
if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
close(sockfd);
continue; /* not fatal */
}
if (listen(sockfd, 5) < 0) {
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++;
if (maxfd < sockfd)
maxfd = sockfd;
}
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)) {
close(sockfd);
return 0;
}
if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) {
close(sockfd);
return 0;
}
if (listen(sockfd, 5) < 0) {
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);
}
}
}
}
/* if any standard file descriptor is missing open it to /dev/null */
static void sanitize_stdfds(void)
{
int fd = open("/dev/null", O_RDWR, 0);
while (fd != -1 && fd < 2)
fd = dup(fd);
if (fd == -1)
die_errno("open /dev/null or dup failed");
if (fd > 2)
close(fd);
}
#ifdef NO_POSIX_GOODIES
struct credentials;
static void drop_privileges(struct credentials *cred)
{
/* nothing */
}
static void daemonize(void)
{
die("--detach not supported on this platform");
}
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;
}
static void daemonize(void)
{
switch (fork()) {
case 0:
break;
case -1:
die_errno("fork failed");
default:
exit(0);
}
if (setsid() == -1)
die_errno("setsid failed");
close(0);
close(1);
close(2);
sanitize_stdfds();
}
#endif
static void store_pid(const char *path)
{
FILE *f = fopen(path, "w");
if (!f)
die_errno("cannot open pid file '%s'", path);
if (fprintf(f, "%"PRIuMAX"\n", (uintmax_t) getpid()) < 0 || fclose(f) != 0)
die_errno("failed to write pid file '%s'", path);
}
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);
return service_loop(&socklist);
}
int main(int argc, 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;
git_extract_argv0_path(argv[0]);
for (i = 1; i < argc; i++) {
char *arg = argv[i];
if (!prefixcmp(arg, "--listen=")) {
string_list_append(&listen_addr, xstrdup_tolower(arg + 9));
continue;
}
if (!prefixcmp(arg, "--port=")) {
char *end;
unsigned long n;
n = strtoul(arg+7, &end, 0);
if (arg[7] && !*end) {
listen_port = n;
continue;
}
}
if (!strcmp(arg, "--serve")) {
serve_mode = 1;
continue;
}
if (!strcmp(arg, "--inetd")) {
inetd_mode = 1;
log_syslog = 1;
continue;
}
if (!strcmp(arg, "--verbose")) {
verbose = 1;
continue;
}
if (!strcmp(arg, "--syslog")) {
log_syslog = 1;
continue;
}
if (!strcmp(arg, "--export-all")) {
export_all_trees = 1;
continue;
}
if (!prefixcmp(arg, "--timeout=")) {
timeout = atoi(arg+10);
continue;
}
if (!prefixcmp(arg, "--init-timeout=")) {
init_timeout = atoi(arg+15);
continue;
}
if (!prefixcmp(arg, "--max-connections=")) {
max_connections = atoi(arg+18);
if (max_connections < 0)
max_connections = 0; /* unlimited */
continue;
}
if (!strcmp(arg, "--strict-paths")) {
strict_paths = 1;
continue;
}
if (!prefixcmp(arg, "--base-path=")) {
base_path = arg+12;
continue;
}
if (!strcmp(arg, "--base-path-relaxed")) {
base_path_relaxed = 1;
continue;
}
if (!prefixcmp(arg, "--interpolated-path=")) {
interpolated_path = arg+20;
continue;
}
if (!strcmp(arg, "--reuseaddr")) {
reuseaddr = 1;
continue;
}
if (!strcmp(arg, "--user-path")) {
user_path = "";
continue;
}
if (!prefixcmp(arg, "--user-path=")) {
user_path = arg + 12;
continue;
}
if (!prefixcmp(arg, "--pid-file=")) {
pid_file = arg + 11;
continue;
}
if (!strcmp(arg, "--detach")) {
detach = 1;
log_syslog = 1;
continue;
}
if (!prefixcmp(arg, "--user=")) {
user_name = arg + 7;
continue;
}
if (!prefixcmp(arg, "--group=")) {
group_name = arg + 8;
continue;
}
if (!prefixcmp(arg, "--enable=")) {
enable_service(arg + 9, 1);
continue;
}
if (!prefixcmp(arg, "--disable=")) {
enable_service(arg + 10, 0);
continue;
}
if (!prefixcmp(arg, "--allow-override=")) {
make_service_overridable(arg + 17, 1);
continue;
}
if (!prefixcmp(arg, "--forbid-override=")) {
make_service_overridable(arg + 18, 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_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 (inetd_mode) {
if (!freopen("/dev/null", "w", stderr))
die_errno("failed to redirect stderr to /dev/null");
}
if (inetd_mode || serve_mode)
return execute();
if (detach) {
daemonize();
loginfo("Ready to rumble");
}
else
sanitize_stdfds();
if (pid_file)
store_pid(pid_file);
/* prepare argv for serving-processes */
cld_argv = xmalloc(sizeof (char *) * (argc + 2));
cld_argv[0] = argv[0]; /* git-daemon */
cld_argv[1] = "--serve";
for (i = 1; i < argc; ++i)
cld_argv[i+1] = argv[i];
cld_argv[argc+1] = NULL;
return serve(&listen_addr, listen_port, cred);
}