pretend-git/daemon.c at master · submitgit/pretend-git · GitHub

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#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

#ifdef NO_INITGROUPS

#define initgroups(x, y) (0) /* nothing */

#endif

static int log_syslog;

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"

" [<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 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)

{

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);

}

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];

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);

snprintf(rpath, PATH_MAX, "%.*s/%s%.*s",

namlen, dir, user_path, restlen, slash);

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);

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 int daemon_error(const char *dir, const char *msg)

{

if (!informative_errors)

msg = "access denied or repository not exported";

packet_write(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 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();

}

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 = CHILD_PROCESS_INIT;

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 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.

static void 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;

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");

}

* 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(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 int execute(void)

{

char *line = packet_buffer;

int pktlen, len, i;

char *addr = getenv("REMOTE_ADDR"), *port = getenv("REMOTE_PORT");

struct hostinfo hi;

hostinfo_init(&hi);

if (addr)

loginfo("Connection from %s:%s", addr, port);

alarm(init_timeout ? init_timeout : timeout);

pktlen = packet_read(0, NULL, NULL, packet_buffer, sizeof(packet_buffer), 0);

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--;

}

if (len != pktlen)

parse_host_arg(&hi, 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);

hostinfo_clear(&hi);

return rc;

}

hostinfo_clear(&hi);

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 = CHILD_PROCESS_INIT;

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->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);

}

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:

strcpy(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;

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)) {

logerror("Could not set SO_REUSEADDR: %s", strerror(errno));

close(sockfd);

continue;

}

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) {

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