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clientserver.c
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clientserver.c
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/*
* The socket based protocol for setting up a connection with rsyncd.
*
* Copyright (C) 1998-2001 Andrew Tridgell <tridge@samba.org>
* Copyright (C) 2001-2002 Martin Pool <mbp@samba.org>
* Copyright (C) 2002-2022 Wayne Davison
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, visit the http://fsf.org website.
*/
#include "rsync.h"
#include "itypes.h"
#include "ifuncs.h"
extern int quiet;
extern int dry_run;
extern int output_motd;
extern int list_only;
extern int am_sender;
extern int am_server;
extern int am_daemon;
extern int am_root;
extern int msgs2stderr;
extern int rsync_port;
extern int protect_args;
extern int ignore_errors;
extern int preserve_xattrs;
extern int kluge_around_eof;
extern int munge_symlinks;
extern int open_noatime;
extern int sanitize_paths;
extern int numeric_ids;
extern int filesfrom_fd;
extern int remote_protocol;
extern int protocol_version;
extern int io_timeout;
extern int no_detach;
extern int write_batch;
extern int old_style_args;
extern int default_af_hint;
extern int logfile_format_has_i;
extern int logfile_format_has_o_or_i;
extern char *bind_address;
extern char *config_file;
extern char *logfile_format;
extern char *files_from;
extern char *tmpdir;
extern char *early_input_file;
extern struct chmod_mode_struct *chmod_modes;
extern filter_rule_list daemon_filter_list;
#ifdef ICONV_OPTION
extern char *iconv_opt;
extern iconv_t ic_send, ic_recv;
#endif
extern uid_t our_uid;
extern gid_t our_gid;
char *auth_user;
char *daemon_auth_choices;
int read_only = 0;
int module_id = -1;
int pid_file_fd = -1;
int early_input_len = 0;
char *early_input = NULL;
pid_t namecvt_pid = 0;
struct chmod_mode_struct *daemon_chmod_modes;
#define EARLY_INPUT_CMD "#early_input="
#define EARLY_INPUT_CMDLEN (sizeof EARLY_INPUT_CMD - 1)
/* module_dirlen is the length of the module_dir string when in daemon
* mode and module_dir is not "/"; otherwise 0. (Note that a chroot-
* enabled module can have a non-"/" module_dir these days.) */
char *module_dir = NULL;
unsigned int module_dirlen = 0;
char *full_module_path;
static int rl_nulls = 0;
static int namecvt_fd_req = -1, namecvt_fd_ans = -1;
#ifdef HAVE_SIGACTION
static struct sigaction sigact;
#endif
static item_list gid_list = EMPTY_ITEM_LIST;
/* Used when "reverse lookup" is off. */
const char undetermined_hostname[] = "UNDETERMINED";
/**
* Run a client connected to an rsyncd. The alternative to this
* function for remote-shell connections is do_cmd().
*
* After negotiating which module to use and reading the server's
* motd, this hands over to client_run(). Telling the server the
* module will cause it to chroot/setuid/etc.
*
* Instead of doing a transfer, the client may at this stage instead
* get a listing of remote modules and exit.
*
* @return -1 for error in startup, or the result of client_run().
* Either way, it eventually gets passed to exit_cleanup().
**/
int start_socket_client(char *host, int remote_argc, char *remote_argv[],
int argc, char *argv[])
{
int fd, ret;
char *p, *user = NULL;
/* This is redundant with code in start_inband_exchange(), but this
* short-circuits a problem in the client before we open a socket,
* and the extra check won't hurt. */
if (**remote_argv == '/') {
rprintf(FERROR,
"ERROR: The remote path must start with a module name not a /\n");
return -1;
}
if ((p = strrchr(host, '@')) != NULL) {
user = host;
host = p+1;
*p = '\0';
}
fd = open_socket_out_wrapped(host, rsync_port, bind_address, default_af_hint);
if (fd == -1)
exit_cleanup(RERR_SOCKETIO);
#ifdef ICONV_CONST
setup_iconv();
#endif
ret = start_inband_exchange(fd, fd, user, remote_argc, remote_argv);
return ret ? ret : client_run(fd, fd, -1, argc, argv);
}
static int exchange_protocols(int f_in, int f_out, char *buf, size_t bufsiz, int am_client)
{
int remote_sub = -1;
int our_sub = get_subprotocol_version();
output_daemon_greeting(f_out, am_client);
if (!am_client) {
char *motd = lp_motd_file();
if (motd && *motd) {
FILE *f = fopen(motd, "r");
while (f && !feof(f)) {
int len = fread(buf, 1, bufsiz - 1, f);
if (len > 0)
write_buf(f_out, buf, len);
}
if (f)
fclose(f);
write_sbuf(f_out, "\n");
}
}
/* This strips the \n. */
if (!read_line_old(f_in, buf, bufsiz, 0)) {
if (am_client)
rprintf(FERROR, "rsync: did not see server greeting\n");
return -1;
}
if (sscanf(buf, "@RSYNCD: %d.%d", &remote_protocol, &remote_sub) < 1) {
if (am_client)
rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n", buf);
else
io_printf(f_out, "@ERROR: protocol startup error\n");
return -1;
}
if (remote_sub < 0) {
if (remote_protocol >= 30) {
if (am_client)
rprintf(FERROR, "rsync: the server omitted the subprotocol value: %s\n", buf);
else
io_printf(f_out, "@ERROR: your client omitted the subprotocol value: %s\n", buf);
return -1;
}
remote_sub = 0;
}
daemon_auth_choices = strchr(buf + 9, ' ');
if (daemon_auth_choices) {
char *cp;
daemon_auth_choices = strdup(daemon_auth_choices + 1);
if ((cp = strchr(daemon_auth_choices, '\n')) != NULL)
*cp = '\0';
} else if (remote_protocol > 31) {
if (am_client)
rprintf(FERROR, "rsync: the server omitted the digest name list: %s\n", buf);
else
io_printf(f_out, "@ERROR: your client omitted the digest name list: %s\n", buf);
return -1;
}
if (protocol_version > remote_protocol) {
protocol_version = remote_protocol;
if (remote_sub)
protocol_version--;
} else if (protocol_version == remote_protocol) {
if (remote_sub != our_sub)
protocol_version--;
}
#if SUBPROTOCOL_VERSION != 0
else if (protocol_version < remote_protocol) {
if (our_sub)
protocol_version--;
}
#endif
if (protocol_version >= 30)
rl_nulls = 1;
return 0;
}
int start_inband_exchange(int f_in, int f_out, const char *user, int argc, char *argv[])
{
int i, modlen;
char line[BIGPATHBUFLEN];
char *sargs[MAX_ARGS];
int sargc = 0;
char *p, *modname;
assert(argc > 0 && *argv != NULL);
if (**argv == '/') {
rprintf(FERROR,
"ERROR: The remote path must start with a module name\n");
return -1;
}
if (!(p = strchr(*argv, '/')))
modlen = strlen(*argv);
else
modlen = p - *argv;
modname = new_array(char, modlen+1+1); /* room for '/' & '\0' */
strlcpy(modname, *argv, modlen + 1);
modname[modlen] = '/';
modname[modlen+1] = '\0';
if (!user)
user = getenv("USER");
if (!user)
user = getenv("LOGNAME");
if (exchange_protocols(f_in, f_out, line, sizeof line, 1) < 0)
return -1;
if (early_input_file) {
STRUCT_STAT st;
FILE *f = fopen(early_input_file, "rb");
if (!f || do_fstat(fileno(f), &st) < 0) {
rsyserr(FERROR, errno, "failed to open %s", early_input_file);
return -1;
}
early_input_len = st.st_size;
if (early_input_len > (int)sizeof line) {
rprintf(FERROR, "%s is > %d bytes.\n", early_input_file, (int)sizeof line);
return -1;
}
if (early_input_len > 0) {
io_printf(f_out, EARLY_INPUT_CMD "%d\n", early_input_len);
while (early_input_len > 0) {
int len;
if (feof(f)) {
rprintf(FERROR, "Early EOF in %s\n", early_input_file);
return -1;
}
len = fread(line, 1, early_input_len, f);
if (len > 0) {
write_buf(f_out, line, len);
early_input_len -= len;
}
}
}
fclose(f);
}
server_options(sargs, &sargc);
if (sargc >= MAX_ARGS - 2)
goto arg_overflow;
sargs[sargc++] = ".";
if (!old_style_args)
snprintf(line, sizeof line, " %.*s/", modlen, modname);
while (argc > 0) {
if (sargc >= MAX_ARGS - 1) {
arg_overflow:
rprintf(FERROR, "internal: args[] overflowed in do_cmd()\n");
exit_cleanup(RERR_SYNTAX);
}
if (strncmp(*argv, modname, modlen) == 0 && argv[0][modlen] == '\0')
sargs[sargc++] = modname; /* we send "modname/" */
else {
char *arg = *argv;
int extra_chars = *arg == '-' ? 2 : 0; /* a leading dash needs a "./" prefix. */
/* If --old-args was not specified, make sure that the arg won't split at a mod name! */
if (!old_style_args && (p = strstr(arg, line)) != NULL) {
do {
extra_chars += 2;
} while ((p = strstr(p+1, line)) != NULL);
}
if (extra_chars) {
char *f = arg;
char *t = arg = new_array(char, strlen(arg) + extra_chars + 1);
if (*f == '-') {
*t++ = '.';
*t++ = '/';
}
while (*f) {
if (*f == ' ' && strncmp(f, line, modlen+2) == 0) {
*t++ = '[';
*t++ = *f++;
*t++ = ']';
} else
*t++ = *f++;
}
*t = '\0';
}
sargs[sargc++] = arg;
}
argv++;
argc--;
}
sargs[sargc] = NULL;
if (DEBUG_GTE(CMD, 1))
print_child_argv("sending daemon args:", sargs);
io_printf(f_out, "%.*s\n", modlen, modname);
/* Old servers may just drop the connection here,
rather than sending a proper EXIT command. Yuck. */
kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0;
while (1) {
if (!read_line_old(f_in, line, sizeof line, 0)) {
rprintf(FERROR, "rsync: didn't get server startup line\n");
return -1;
}
if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
auth_client(f_out, user, line+18);
continue;
}
if (strcmp(line,"@RSYNCD: OK") == 0)
break;
if (strcmp(line,"@RSYNCD: EXIT") == 0) {
/* This is sent by recent versions of the
* server to terminate the listing of modules.
* We don't want to go on and transfer
* anything; just exit. */
exit(0);
}
if (strncmp(line, "@ERROR", 6) == 0) {
rprintf(FERROR, "%s\n", line);
/* This is always fatal; the server will now
* close the socket. */
return -1;
}
/* This might be a MOTD line or a module listing, but there is
* no way to differentiate it. The manpage mentions this. */
if (output_motd)
rprintf(FINFO, "%s\n", line);
}
kluge_around_eof = 0;
if (rl_nulls) {
for (i = 0; i < sargc; i++) {
if (!sargs[i]) /* stop at --secluded-args NULL */
break;
write_sbuf(f_out, sargs[i]);
write_byte(f_out, 0);
}
write_byte(f_out, 0);
} else {
for (i = 0; i < sargc; i++)
io_printf(f_out, "%s\n", sargs[i]);
write_sbuf(f_out, "\n");
}
if (protect_args)
send_protected_args(f_out, sargs);
if (protocol_version < 23) {
if (protocol_version == 22 || !am_sender)
io_start_multiplex_in(f_in);
}
free(modname);
return 0;
}
#if defined HAVE_SETENV || defined HAVE_PUTENV
static int read_arg_from_pipe(int fd, char *buf, int limit)
{
char *bp = buf, *eob = buf + limit - 1;
while (1) {
int got = read(fd, bp, 1);
if (got != 1) {
if (got < 0 && errno == EINTR)
continue;
return -1;
}
if (*bp == '\0')
break;
if (bp < eob)
bp++;
}
*bp = '\0';
return bp - buf;
}
#endif
void set_env_str(const char *var, const char *str)
{
#ifdef HAVE_SETENV
if (setenv(var, str, 1) < 0)
out_of_memory("set_env_str");
#else
#ifdef HAVE_PUTENV
char *mem;
if (asprintf(&mem, "%s=%s", var, str) < 0)
out_of_memory("set_env_str");
putenv(mem);
#else
(void)var;
(void)str;
#endif
#endif
}
#if defined HAVE_SETENV || defined HAVE_PUTENV
static void set_envN_str(const char *var, int num, const char *str)
{
#ifdef HAVE_SETENV
char buf[128];
(void)snprintf(buf, sizeof buf, "%s%d", var, num);
if (setenv(buf, str, 1) < 0)
out_of_memory("set_env_str");
#else
#ifdef HAVE_PUTENV
char *mem;
if (asprintf(&mem, "%s%d=%s", var, num, str) < 0)
out_of_memory("set_envN_str");
putenv(mem);
#endif
#endif
}
void set_env_num(const char *var, long num)
{
#ifdef HAVE_SETENV
char val[64];
(void)snprintf(val, sizeof val, "%ld", num);
if (setenv(var, val, 1) < 0)
out_of_memory("set_env_str");
#else
#ifdef HAVE_PUTENV
char *mem;
if (asprintf(&mem, "%s=%ld", var, num) < 0)
out_of_memory("set_env_num");
putenv(mem);
#endif
#endif
}
/* Used for "early exec", "pre-xfer exec", and the "name converter" script. */
static pid_t start_pre_exec(const char *cmd, int *arg_fd_ptr, int *error_fd_ptr)
{
int arg_fds[2], error_fds[2], arg_fd;
pid_t pid;
if ((error_fd_ptr && pipe(error_fds) < 0) || pipe(arg_fds) < 0 || (pid = fork()) < 0)
return (pid_t)-1;
if (pid == 0) {
char buf[BIGPATHBUFLEN];
int j, len, status;
if (error_fd_ptr) {
close(error_fds[0]);
set_blocking(error_fds[1]);
}
close(arg_fds[1]);
arg_fd = arg_fds[0];
set_blocking(arg_fd);
len = read_arg_from_pipe(arg_fd, buf, BIGPATHBUFLEN);
if (len <= 0)
_exit(1);
set_env_str("RSYNC_REQUEST", buf);
for (j = 0; ; j++) {
len = read_arg_from_pipe(arg_fd, buf, BIGPATHBUFLEN);
if (len <= 0) {
if (!len)
break;
_exit(1);
}
set_envN_str("RSYNC_ARG", j, buf);
}
dup2(arg_fd, STDIN_FILENO);
close(arg_fd);
if (error_fd_ptr) {
dup2(error_fds[1], STDOUT_FILENO);
close(error_fds[1]);
}
status = shell_exec(cmd);
if (!WIFEXITED(status))
_exit(1);
_exit(WEXITSTATUS(status));
}
if (error_fd_ptr) {
close(error_fds[1]);
*error_fd_ptr = error_fds[0];
set_blocking(error_fds[0]);
}
close(arg_fds[0]);
arg_fd = *arg_fd_ptr = arg_fds[1];
set_blocking(arg_fd);
return pid;
}
#endif
static void write_pre_exec_args(int write_fd, char *request, char **early_argv, char **argv, int exec_type)
{
int j = 0;
if (!request)
request = "(NONE)";
write_buf(write_fd, request, strlen(request)+1);
if (early_argv) {
for ( ; *early_argv; early_argv++)
write_buf(write_fd, *early_argv, strlen(*early_argv)+1);
j = 1; /* Skip arg0 name in argv. */
}
if (argv) {
for ( ; argv[j]; j++)
write_buf(write_fd, argv[j], strlen(argv[j])+1);
}
write_byte(write_fd, 0);
if (exec_type == 1 && early_input_len)
write_buf(write_fd, early_input, early_input_len);
if (exec_type != 2) /* the name converter needs this left open */
close(write_fd);
}
static char *finish_pre_exec(const char *desc, pid_t pid, int read_fd)
{
char buf[BIGPATHBUFLEN], *bp, *cr;
int j, status = -1, msglen = sizeof buf - 1;
if (read_fd >= 0) {
/* Read the stdout from the program. This it is only displayed
* to the user if the script also returns an error status. */
for (bp = buf, cr = buf; msglen > 0; msglen -= j) {
if ((j = read(read_fd, bp, msglen)) <= 0) {
if (j == 0)
break;
if (errno == EINTR)
continue;
break; /* Just ignore the read error for now... */
}
bp[j] = '\0';
while (1) {
if ((cr = strchr(cr, '\r')) == NULL) {
cr = bp + j;
break;
}
if (!cr[1])
break; /* wait for more data before we decide what to do */
if (cr[1] == '\n') {
memmove(cr, cr+1, j - (cr - bp));
j--;
} else
cr++;
}
bp += j;
}
*bp = '\0';
close(read_fd);
} else
*buf = '\0';
if (wait_process(pid, &status, 0) < 0
|| !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
char *e;
if (asprintf(&e, "%s returned failure (%d)%s%s%s\n%s",
desc, status, status < 0 ? ": " : "",
status < 0 ? strerror(errno) : "",
*buf ? ":" : "", buf) < 0)
return "out_of_memory in finish_pre_exec\n";
return e;
}
return NULL;
}
static int path_failure(int f_out, const char *dir, BOOL was_chdir)
{
if (was_chdir)
rsyserr(FLOG, errno, "chdir %s failed", dir);
else
rprintf(FLOG, "normalize_path(%s) failed\n", dir);
io_printf(f_out, "@ERROR: chdir failed\n");
return -1;
}
static int add_a_group(int f_out, const char *gname)
{
gid_t gid, *gid_p;
if (!group_to_gid(gname, &gid, True)) {
rprintf(FLOG, "Invalid gid %s\n", gname);
io_printf(f_out, "@ERROR: invalid gid %s\n", gname);
return -1;
}
gid_p = EXPAND_ITEM_LIST(&gid_list, gid_t, -32);
*gid_p = gid;
return 0;
}
#ifdef HAVE_GETGROUPLIST
static int want_all_groups(int f_out, uid_t uid)
{
const char *err;
if ((err = getallgroups(uid, &gid_list)) != NULL) {
rsyserr(FLOG, errno, "%s", err);
io_printf(f_out, "@ERROR: %s\n", err);
return -1;
}
return 0;
}
#elif defined HAVE_INITGROUPS
static struct passwd *want_all_groups(int f_out, uid_t uid)
{
struct passwd *pw;
gid_t *gid_p;
if ((pw = getpwuid(uid)) == NULL) {
rsyserr(FLOG, errno, "getpwuid failed");
io_printf(f_out, "@ERROR: getpwuid failed\n");
return NULL;
}
/* Start with the default group and initgroups() will add the rest. */
gid_p = EXPAND_ITEM_LIST(&gid_list, gid_t, -32);
*gid_p = pw->pw_gid;
return pw;
}
#endif
static int rsync_module(int f_in, int f_out, int i, const char *addr, const char *host)
{
int argc;
char **argv, **orig_argv, **orig_early_argv, *module_chdir;
char line[BIGPATHBUFLEN];
#if defined HAVE_INITGROUPS && !defined HAVE_GETGROUPLIST
struct passwd *pw = NULL;
#endif
uid_t uid;
int set_uid;
char *p, *err_msg = NULL;
char *name = lp_name(i);
int use_chroot = lp_use_chroot(i); /* might be 1 (yes), 0 (no), or -1 (unset) */
int ret, pre_exec_arg_fd = -1, pre_exec_error_fd = -1;
int save_munge_symlinks;
pid_t pre_exec_pid = 0;
char *request = NULL;
set_env_str("RSYNC_MODULE_NAME", name);
#ifdef ICONV_OPTION
iconv_opt = lp_charset(i);
if (*iconv_opt)
setup_iconv();
iconv_opt = NULL;
#endif
/* If reverse lookup is disabled globally but enabled for this module,
* we need to do it now before the access check. */
if (host == undetermined_hostname && lp_reverse_lookup(i))
host = client_name(client_addr(f_in));
set_env_str("RSYNC_HOST_NAME", host);
set_env_str("RSYNC_HOST_ADDR", addr);
if (!allow_access(addr, &host, i)) {
rprintf(FLOG, "rsync denied on module %s from %s (%s)\n",
name, host, addr);
if (!lp_list(i))
io_printf(f_out, "@ERROR: Unknown module '%s'\n", name);
else {
io_printf(f_out,
"@ERROR: access denied to %s from %s (%s)\n",
name, host, addr);
}
return -1;
}
if (am_daemon > 0) {
rprintf(FLOG, "rsync allowed access on module %s from %s (%s)\n",
name, host, addr);
}
if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) {
if (errno) {
rsyserr(FLOG, errno, "failed to open lock file %s",
lp_lock_file(i));
io_printf(f_out, "@ERROR: failed to open lock file\n");
} else {
rprintf(FLOG, "max connections (%d) reached\n",
lp_max_connections(i));
io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n",
lp_max_connections(i));
}
return -1;
}
read_only = lp_read_only(i); /* may also be overridden by auth_server() */
auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD ");
if (!auth_user) {
io_printf(f_out, "@ERROR: auth failed on module %s\n", name);
return -1;
}
set_env_str("RSYNC_USER_NAME", auth_user);
module_id = i;
if (lp_transfer_logging(module_id) && !logfile_format)
logfile_format = lp_log_format(module_id);
if (log_format_has(logfile_format, 'i'))
logfile_format_has_i = 1;
if (logfile_format_has_i || log_format_has(logfile_format, 'o'))
logfile_format_has_o_or_i = 1;
uid = MY_UID();
am_root = (uid == ROOT_UID);
p = *lp_uid(module_id) ? lp_uid(module_id) : am_root ? NOBODY_USER : NULL;
if (p) {
if (!user_to_uid(p, &uid, True)) {
rprintf(FLOG, "Invalid uid %s\n", p);
io_printf(f_out, "@ERROR: invalid uid %s\n", p);
return -1;
}
set_uid = 1;
} else
set_uid = 0;
p = *lp_gid(module_id) ? conf_strtok(lp_gid(module_id)) : NULL;
if (p) {
/* The "*" gid must be the first item in the list. */
if (strcmp(p, "*") == 0) {
#ifdef HAVE_GETGROUPLIST
if (want_all_groups(f_out, uid) < 0)
return -1;
#elif defined HAVE_INITGROUPS
if ((pw = want_all_groups(f_out, uid)) == NULL)
return -1;
#else
rprintf(FLOG, "This rsync does not support a gid of \"*\"\n");
io_printf(f_out, "@ERROR: invalid gid setting.\n");
return -1;
#endif
} else if (add_a_group(f_out, p) < 0)
return -1;
while ((p = conf_strtok(NULL)) != NULL) {
#if defined HAVE_INITGROUPS && !defined HAVE_GETGROUPLIST
if (pw) {
rprintf(FLOG, "This rsync cannot add groups after \"*\".\n");
io_printf(f_out, "@ERROR: invalid gid setting.\n");
return -1;
}
#endif
if (add_a_group(f_out, p) < 0)
return -1;
}
} else if (am_root) {
if (add_a_group(f_out, NOBODY_GROUP) < 0)
return -1;
}
module_dir = lp_path(module_id);
if (*module_dir == '\0') {
rprintf(FLOG, "No path specified for module %s\n", name);
io_printf(f_out, "@ERROR: no path setting.\n");
return -1;
}
if (use_chroot < 0) {
if (strstr(module_dir, "/./") != NULL)
use_chroot = 1; /* The module is expecting a chroot inner & outer path. */
else if (chroot("/") < 0) {
rprintf(FLOG, "chroot test failed: %s. "
"Switching 'use chroot' from unset to false.\n",
strerror(errno));
use_chroot = 0;
} else {
if (chdir("/") < 0)
rsyserr(FLOG, errno, "chdir(\"/\") failed");
use_chroot = 1;
}
}
if (use_chroot) {
if ((p = strstr(module_dir, "/./")) != NULL) {
*p = '\0'; /* Temporary... */
if (!(module_chdir = normalize_path(module_dir, True, NULL)))
return path_failure(f_out, module_dir, False);
*p = '/';
if (!(p = normalize_path(p + 2, True, &module_dirlen)))
return path_failure(f_out, strstr(module_dir, "/./"), False);
if (!(full_module_path = normalize_path(module_dir, False, NULL)))
full_module_path = module_dir;
module_dir = p;
} else {
if (!(module_chdir = normalize_path(module_dir, False, NULL)))
return path_failure(f_out, module_dir, False);
full_module_path = module_chdir;
module_dir = "/";
module_dirlen = 1;
}
} else {
if (!(module_chdir = normalize_path(module_dir, False, &module_dirlen)))
return path_failure(f_out, module_dir, False);
full_module_path = module_dir = module_chdir;
}
set_env_str("RSYNC_MODULE_PATH", full_module_path);
if (module_dirlen == 1) {
module_dirlen = 0;
set_filter_dir("/", 1);
} else
set_filter_dir(module_dir, module_dirlen);
p = lp_filter(module_id);
parse_filter_str(&daemon_filter_list, p, rule_template(FILTRULE_WORD_SPLIT),
XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3);
p = lp_include_from(module_id);
parse_filter_file(&daemon_filter_list, p, rule_template(FILTRULE_INCLUDE),
XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
p = lp_include(module_id);
parse_filter_str(&daemon_filter_list, p,
rule_template(FILTRULE_INCLUDE | FILTRULE_WORD_SPLIT),
XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES);
p = lp_exclude_from(module_id);
parse_filter_file(&daemon_filter_list, p, rule_template(0),
XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS);
p = lp_exclude(module_id);
parse_filter_str(&daemon_filter_list, p, rule_template(FILTRULE_WORD_SPLIT),
XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES);
log_init(1);
#if defined HAVE_SETENV || defined HAVE_PUTENV
if ((*lp_early_exec(module_id) || *lp_prexfer_exec(module_id)
|| *lp_postxfer_exec(module_id) || *lp_name_converter(module_id))
&& !getenv("RSYNC_NO_XFER_EXEC")) {
set_env_num("RSYNC_PID", (long)getpid());
/* For post-xfer exec, fork a new process to run the rsync
* daemon while this process waits for the exit status and
* runs the indicated command at that point. */
if (*lp_postxfer_exec(module_id)) {
pid_t pid = fork();
if (pid < 0) {
rsyserr(FLOG, errno, "fork failed");
io_printf(f_out, "@ERROR: fork failed\n");
return -1;
}
if (pid) {
int status;
close(f_in);
if (f_out != f_in)
close(f_out);
if (wait_process(pid, &status, 0) < 0)
status = -1;
set_env_num("RSYNC_RAW_STATUS", status);
if (WIFEXITED(status))
status = WEXITSTATUS(status);
else
status = -1;
set_env_num("RSYNC_EXIT_STATUS", status);
if (shell_exec(lp_postxfer_exec(module_id)) < 0)
status = -1;
_exit(status);
}
}
/* For early exec, fork a child process to run the indicated
* command and wait for it to exit. */
if (*lp_early_exec(module_id)) {
int arg_fd;
pid_t pid = start_pre_exec(lp_early_exec(module_id), &arg_fd, NULL);
if (pid == (pid_t)-1) {
rsyserr(FLOG, errno, "early exec preparation failed");
io_printf(f_out, "@ERROR: early exec preparation failed\n");
return -1;
}
write_pre_exec_args(arg_fd, NULL, NULL, NULL, 1);
if (finish_pre_exec("early exec", pid, -1) != NULL) {
rsyserr(FLOG, errno, "early exec failed");
io_printf(f_out, "@ERROR: early exec failed\n");
return -1;
}
}
/* For pre-xfer exec, fork a child process to run the indicated
* command, though it first waits for the parent process to
* send us the user's request via a pipe. */
if (*lp_prexfer_exec(module_id)) {
pre_exec_pid = start_pre_exec(lp_prexfer_exec(module_id), &pre_exec_arg_fd, &pre_exec_error_fd);
if (pre_exec_pid == (pid_t)-1) {
rsyserr(FLOG, errno, "pre-xfer exec preparation failed");
io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n");
return -1;
}
}
if (*lp_name_converter(module_id)) {
namecvt_pid = start_pre_exec(lp_name_converter(module_id), &namecvt_fd_req, &namecvt_fd_ans);
if (namecvt_pid == (pid_t)-1) {
rsyserr(FLOG, errno, "name-converter exec preparation failed");
io_printf(f_out, "@ERROR: name-converter exec preparation failed\n");
return -1;
}
}
}
#endif
if (early_input) {
free(early_input);
early_input = NULL;
}
if (use_chroot) {
if (chroot(module_chdir)) {
rsyserr(FLOG, errno, "chroot(\"%s\") failed", module_chdir);
io_printf(f_out, "@ERROR: chroot failed\n");
return -1;
}
module_chdir = module_dir;
}
if (!change_dir(module_chdir, CD_NORMAL))
return path_failure(f_out, module_chdir, True);
if (module_dirlen)
sanitize_paths = 1;
if ((munge_symlinks = lp_munge_symlinks(module_id)) < 0)
munge_symlinks = !use_chroot || module_dirlen;
if (munge_symlinks) {
STRUCT_STAT st;
char prefix[SYMLINK_PREFIX_LEN]; /* NOT +1 ! */
strlcpy(prefix, SYMLINK_PREFIX, sizeof prefix); /* trim the trailing slash */
if (do_stat(prefix, &st) == 0 && S_ISDIR(st.st_mode)) {
rprintf(FLOG, "Symlink munging is unsafe when a %s directory exists.\n",
prefix);