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daemon_misc.c
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/*
* Copyright (c) 2024, Klara, Inc.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "config.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <limits.h>
#include <pwd.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "daemon.h"
_Static_assert(sizeof(id_t) <= INT_MAX, "{u,g}id_t larger than expected");
static int daemon_rangelock(struct sess *, const char *, const char *, int);
/* Compatible with smb rsync, just in case. */
#define CONNLOCK_START(conn) ((conn) * 4)
#define CONNLOCK_SIZE(conn) (4)
int
daemon_apply_chmod(struct sess *sess, const char *module,
struct opts *opts)
{
struct daemon_role *role;
const char *chmod, *which;
int rc;
role = (void *)sess->role;
if (opts->sender)
which = "outgoing chmod";
else
which = "incoming chmod";
if (!cfg_has_param(role->dcfg, module, which))
return 1;
rc = cfg_param_str(role->dcfg, module, which, &chmod);
assert(rc == 0);
rc = chmod_parse(chmod, sess);
if (rc != 0) {
daemon_client_error(sess, "%s: failed to parse '%s': %s",
module, which, strerror(rc));
return 0;
}
opts->chmod = chmod;
return 1;
}
int
daemon_apply_chrootopts(struct sess *sess, const char *module,
struct opts *opts, int use_chroot)
{
struct daemon_role *role;
int bnids;
role = (void *)sess->role;
/* If the client requested --numeric-ids, we'll just leave it be. */
if (opts->numeric_ids != NIDS_OFF)
return 1;
/*
* If the parameter's not been specified, then its default depends on
* whether we're chrooted or not. Note that `use_chroot` may be 0, 1,
* or 2, but the distinction between 1 and 2 (must chroot, try chroot)
* does not mattter because the caller shouldn't pass a try chroot if
* the chroot failed.
*/
if (!cfg_has_param(role->dcfg, module, "numeric ids")) {
/*
* The client isn't aware that we're running with --numeric-ids,
* so we had to make this a tri-state to support a mode where we
* still send an empty list.
*/
if (use_chroot)
opts->numeric_ids = NIDS_STEALTH;
else
opts->numeric_ids = NIDS_OFF;
return 1;
}
/*
* Otherwise, we'll defer to a config-set value of numeric ids to
* determine if we're doing it or not.
*/
if (cfg_param_bool(role->dcfg, module, "numeric ids", &bnids) != 0) {
ERR("%s: 'numeric ids' invalid", module);
return 0;
}
if (bnids)
opts->numeric_ids = NIDS_STEALTH;
return 1;
}
int
daemon_apply_ignoreopts(struct sess *sess, const char *module, struct opts *opts)
{
struct daemon_role *role;
role = (void *)sess->role;
if (!opts->ignore_errors &&
cfg_param_bool(role->dcfg, module, "ignore errors",
&opts->ignore_errors) != 0) {
daemon_client_error(sess, "%s: 'ignore errors' invalid");
return 0;
}
if (cfg_param_bool(role->dcfg, module, "ignore nonreadable",
&opts->ignore_nonreadable) != 0) {
daemon_client_error(sess, "%s: 'ignore nonreadable' invalid");
return 0;
}
return 1;
}
static const char *
daemon_fetch_outfmt(const struct sess *sess, void *cookie, char field)
{
struct daemon_role *role;
role = cookie;
switch (field) {
case 'a':
return role->client_addr;
case 'h':
return role->client_host;
case 'm':
return role->module;
case 'P':
return role->module_path;
case 'u':
return role->auth_user;
default:
break;
}
return NULL;
}
int
daemon_apply_xferlog(struct sess *sess, const char *module, struct opts *opts)
{
struct daemon_role *role;
int logging;
role = (void *)sess->role;
if (cfg_param_bool(role->dcfg, module, "transfer logging",
&logging) != 0) {
daemon_client_error(sess, "%s: 'transfer logging' invalid");
return 0;
}
if (!logging) {
opts->outformat = NULL;
} else if (opts->outformat == NULL) {
int rc;
rc = cfg_param_str(role->dcfg, module, "log format", &opts->outformat);
assert(rc == 0);
}
if (opts->outformat != NULL) {
int printflags;
printflags = output(sess, NULL, 0);
if ((printflags & 1) != 0)
sess->itemize = 1;
if ((printflags & 2) != 0)
sess->lateprint = 1;
sess->role->role_fetch_outfmt = daemon_fetch_outfmt;
sess->role->role_fetch_outfmt_cookie = sess->role;
}
return 1;
}
static int
daemon_chuser_resolve_name(const char *name, bool is_gid, id_t *oid)
{
struct passwd *pwd;
struct group *grp;
char *endp;
long long rid;
if (is_gid) {
grp = getgrnam(name);
if (grp != NULL) {
*oid = grp->gr_gid;
return 1;
}
} else {
pwd = getpwnam(name);
if (pwd != NULL) {
*oid = pwd->pw_uid;
return 1;
}
}
errno = 0;
rid = strtoll(name, &endp, 10);
if (errno != 0 || *endp != '\0')
return 0;
if (rid < INT_MIN || rid > INT_MAX)
return 0;
*oid = (id_t)rid;
return 1;
}
int
daemon_chuser_setup(struct sess *sess, const char *module)
{
struct daemon_role *role;
const char *gidstr, *uidstr;
int rc;
role = (void *)sess->role;
role->do_setid = geteuid() == 0;
/* If we aren't root, nothing to do. */
if (!role->do_setid)
return 1;
rc = cfg_param_str(role->dcfg, module, "uid", &uidstr);
assert(rc == 0);
if (!daemon_chuser_resolve_name(uidstr, false, &role->uid)) {
daemon_client_error(sess, "%s: uid '%s' invalid",
module, uidstr);
return 0;
}
if (cfg_has_param(role->dcfg, module, "gid")) {
/* Group specified - it must resolve. */
rc = cfg_param_str(role->dcfg, module, "gid", &gidstr);
assert(rc == 0);
if (!daemon_chuser_resolve_name(gidstr, true, &role->gid)) {
daemon_client_error(sess, "%s: gid '%s' invalid",
module, gidstr);
return 0;
}
return 1;
}
/*
* No group specified; try "nobody", then "nogroup", before erroring
* out.
*/
if (daemon_chuser_resolve_name("nobody", true, &role->gid))
return 1;
else if (daemon_chuser_resolve_name("nogroup", true, &role->gid))
return 1;
daemon_client_error(sess, "%s: no gid specified, cannot find one to use",
module);
return 0;
}
int
daemon_chuser(struct sess *sess, const char *module)
{
struct daemon_role *role;
role = (void *)sess->role;
if (!role->do_setid)
return 1;
if (role->gid != 0 && setgid((gid_t)role->gid) == -1) {
daemon_client_error(sess, "%s: setgid to '%d' failed",
module, role->gid);
return 0;
}
if (role->uid != 0 && setuid((uid_t)role->uid) == -1) {
daemon_client_error(sess, "%s: setuid to '%d' failed",
module, role->uid);
return 0;
}
return 1;
}
void
daemon_client_error(struct sess *sess, const char *fmt, ...)
{
struct daemon_role *role;
char *msg;
va_list ap;
int msgsz;
role = (void *)sess->role;
va_start(ap, fmt);
if ((msgsz = vasprintf(&msg, fmt, ap)) != -1) {
if (!sess->mplex_writes) {
if (!io_write_buf(sess, role->client, "@ERROR ",
sizeof("@ERROR ") - 1) ||
!io_write_line(sess, role->client, msg)) {
ERR("io_write");
}
} else {
if (!io_write_buf_tagged(sess, role->client, msg,
msgsz, IT_ERROR_XFER)) {
ERR("io_write");
} else if(!io_write_buf_tagged(sess, role->client, "\n",
1, IT_ERROR_XFER)) {
ERR("io_write");
}
}
free(msg);
}
va_end(ap);
/*
* We may want to log this to the log file as well, but for now we'll
* settle on just making the client aware.
*/
}
static void
daemon_configure_filter_type(struct daemon_role *role, const char *module,
const char *fparam, enum rule_type type, bool is_file)
{
const char *filter;
int rc;
if (!cfg_has_param(role->dcfg, module, fparam))
return;
rc = cfg_param_str(role->dcfg, module, fparam, &filter);
assert(rc == 0);
if (is_file)
parse_file(filter, type, '\n');
else
parse_rule_words(filter, type, '\n');
}
int
daemon_configure_filters(struct sess *sess, const char *module)
{
struct daemon_role *role;
role = (void *)sess->role;
daemon_configure_filter_type(role, module, "filter", RULE_NONE, false);
daemon_configure_filter_type(role, module, "include from", RULE_INCLUDE,
true);
daemon_configure_filter_type(role, module, "include", RULE_INCLUDE,
false);
daemon_configure_filter_type(role, module, "exclude from", RULE_EXCLUDE,
true);
daemon_configure_filter_type(role, module, "exclude", RULE_EXCLUDE,
false);
return 1;
}
static long
parse_addr(sa_family_t family, const char *strmask, struct sockaddr *maskaddr)
{
void *addr;
if (family == AF_INET) {
struct sockaddr_in *sin = (void *)maskaddr;
addr = &sin->sin_addr;
} else {
struct sockaddr_in6 *sin6 = (void *)maskaddr;
addr = &sin6->sin6_addr;
}
if (inet_pton(family, strmask, addr) != 1)
return 0;
maskaddr->sa_family = family;
return 1;
}
static long
parse_mask(sa_family_t family, const char *strmask, struct sockaddr *maskaddr)
{
char *endp;
unsigned long mask;
errno = 0;
mask = strtoul(strmask, &endp, 10);
if (errno == 0 && *endp == '\0') {
uint8_t *addr;
size_t addrsz, nbytes;
int rem;
/* No sanity checking at all. */
if (family == AF_INET) {
struct sockaddr_in *sin = (void *)maskaddr;
addr = (uint8_t *)&sin->sin_addr;
addrsz = sizeof(sin->sin_addr);
} else {
struct sockaddr_in6 *sin6 = (void *)maskaddr;
addr = (uint8_t *)&sin6->sin6_addr;
addrsz = sizeof(sin6->sin6_addr);
}
memset(addr, 0, addrsz);
/* Invalid... */
if (mask > (addrsz << 3))
return 0;
/*
* We can memset up until the last byte of the mask, then
* set the remainder manually.
*/
nbytes = mask >> 3;
/* Recalculate our last byte's worth, if any. */
rem = mask & 0x07; /* Truncated bits */
mask = ~((1 << (8 - rem)) - 1);
memset(addr, 0xff, nbytes);
if (rem != 0)
addr[nbytes] |= mask;
return 1;
}
/* Must be an address mask... */
if (parse_addr(family, strmask, maskaddr))
return 1;
return 0;
}
static int
masked_match(char *host, struct sockaddr *addr)
{
struct sockaddr_storage hostaddr, maskaddr;
uint8_t *laddr, *maddr, *raddr;
char *strmask;
size_t addrsz;
sa_family_t family;
family = addr->sa_family;
strmask = strrchr(host, '/');
assert(strmask != NULL);
if (!parse_mask(family, strmask + 1, (struct sockaddr *)&maskaddr))
return 0;
*strmask = '\0';
if (!parse_addr(family, host, (struct sockaddr *)&hostaddr))
return 0;
if (family == AF_INET) {
struct sockaddr_in *left, *right, *mask;
left = (struct sockaddr_in *)&hostaddr;
right = (struct sockaddr_in *)addr;
mask = (struct sockaddr_in *)&maskaddr;
laddr = (uint8_t *)&left->sin_addr;
raddr = (uint8_t *)&right->sin_addr;
maddr = (uint8_t *)&mask->sin_addr;
addrsz = sizeof(left->sin_addr);
} else {
struct sockaddr_in6 *left, *right, *mask;
left = (struct sockaddr_in6 *)&hostaddr;
right = (struct sockaddr_in6 *)addr;
mask = (struct sockaddr_in6 *)&maskaddr;
laddr = (uint8_t *)&left->sin6_addr;
raddr = (uint8_t *)&right->sin6_addr;
maddr = (uint8_t *)&mask->sin6_addr;
addrsz = sizeof(left->sin6_addr);
}
/* Finally, compare the two. */
for (size_t i = 0; i < addrsz; i++) {
if (((laddr[i] ^ raddr[i]) & maddr[i]) != 0)
return 0;
}
return 1;
}
static int
daemon_connection_matches_one(const struct sess *sess, char *host)
{
const struct daemon_role *role;
const char *addr, *masked;
role = (void *)sess->role;
if (role->client_host[0] != '\0' &&
rmatch(host, role->client_host, 0) == 0)
return 1;
masked = strrchr(host, '/');
addr = &role->client_addr[0];
if (masked == NULL)
return strcmp(host, addr) == 0;
return masked_match(host, role->client_sa);
}
static int
daemon_connection_matches(struct sess *sess, const char *hostlistp, bool *match,
int *total)
{
char *host, *hostlist;
int cnt;
bool matched;
hostlist = strdup(hostlistp);
if (hostlist == NULL) {
daemon_client_error(sess, "out of memory");
return -1;
}
cnt = 0;
matched = false;
while ((host = strsep(&hostlist, ", \t")) != NULL) {
if (*host == '\0')
continue;
cnt++;
/* Check host */
if (daemon_connection_matches_one(sess, host)) {
matched = true;
break;
}
}
*total = cnt;
*match = matched;
free(hostlist);
return 0;
}
/* Check 'hosts allow' and 'hosts deny' */
int
daemon_connection_allowed(struct sess *sess, const char *module)
{
struct daemon_role *role;
const char *hostlist;
int allowcnt, denycnt, rc;
bool has_deny, matched;
role = (void *)sess->role;
allowcnt = denycnt = 0;
has_deny = cfg_has_param(role->dcfg, module, "hosts deny");
if (cfg_has_param(role->dcfg, module, "hosts allow")) {
rc = cfg_param_str(role->dcfg, module, "hosts allow",
&hostlist);
assert(rc == 0);
/* Fail safe, don't allow if we failed to parse. */
if (daemon_connection_matches(sess, hostlist,
&matched, &allowcnt) == -1) {
daemon_client_error(sess, "failed to process allow host list");
return 0;
}
if (allowcnt > 0) {
if (matched)
return 1;
if (!has_deny) {
daemon_client_error(sess,
"access denied by allow policy from %s [%s]",
role->client_host, role->client_addr);
return 0;
}
}
}
if (has_deny) {
rc = cfg_param_str(role->dcfg, module, "hosts deny",
&hostlist);
assert(rc == 0);
/* Fail safe, don't allow if we failed to parse. */
if (daemon_connection_matches(sess, hostlist,
&matched, &denycnt) == -1) {
daemon_client_error(sess, "failed to process deny host list");
return 0;
}
if (denycnt > 0) {
if (matched) {
daemon_client_error(sess,
"access denied by deny policy from %s [%s]",
role->client_host, role->client_addr);
return 0;
}
} else if (allowcnt > 0) {
/*
* We had an allow list and we thought we had a deny
* list, but we parsed the list only to discover it was
* actually empty. Deny the connection, since they were
* not allowed by the allow list.
*/
daemon_client_error(sess,
"access denied by allow policy from %s [%s]",
role->client_host, role->client_addr);
return 0;
}
}
/* Default policy is to accept all. */
return 1;
}
/*
* Return value of this one is reversed, as we're describing whether the
* connection is being limited from happening or not.
*/
int
daemon_connection_limited(struct sess *sess, const char *module)
{
struct daemon_role *role;
const char *lockf;
int max, rc;
role = (void *)sess->role;
if (cfg_param_int(role->dcfg, module, "max connections", &max) != 0) {
ERRX("%s: 'max connections' invalid", module);
return 1;
}
if (max < 0) {
/* Disabled */
daemon_client_error(sess,
"module '%s' is currently disabled", module);
return 1;
} else if (max == 0) {
/* Unlimited allowed */
return 0;
}
rc = cfg_param_str(role->dcfg, module, "lock file", &lockf);
assert(rc == 0);
if (*lockf == '\0') {
ERR("%s: 'lock file' is empty with 'max connections' in place", module);
return 1;
}
return !daemon_rangelock(sess, module, lockf, max);
}
/*
* Done in the child for both pre-xfer and post-xfer commands
*/
static void
daemon_do_execcmds_common_env(struct daemon_role *role, const char *module)
{
setenv("RSYNC_MODULE_NAME", module, 1);
setenv("RSYNC_MODULE_PATH", role->module_path, 1);
setenv("RSYNC_HOST_ADDR", role->client_addr, 1);
setenv("RSYNC_HOST_NAME", role->client_host, 1);
setenv("RSYNC_USER_NAME",
(role->auth_user != NULL ? role->auth_user : ""), 1);
}
/*
* The reference rsync seems to ignore, e.g., out of memory errors when trying
* to construct the environment, so we'll do the same.
*/
static void
daemon_do_execcmds_num_env(const char *name, unsigned long val)
{
char fmtbuf[32];
int ret;
ret = snprintf(fmtbuf, sizeof(fmtbuf), "%ld", val);
if (ret < 0 || ret >= (int)sizeof(fmtbuf))
return; /* Overflow or error */
setenv(name, fmtbuf, 1);
}
static int
daemon_await_prexfer_env_read(int infd, void *bufp, size_t bufsz)
{
uint8_t *buf = bufp;
size_t offset;
ssize_t readsz;
offset = 0;
while (bufsz != 0) {
readsz = read(infd, &buf[offset], bufsz);
if (readsz <= 0) {
if (readsz == -1 && (errno == EINTR || errno == EAGAIN))
continue;
return 0;
}
offset += readsz;
bufsz -= readsz;
}
return 1;
}
static uint8_t *
daemon_await_prexfer_env(struct daemon_role *role, int infd, size_t *obufsz)
{
uint8_t *penv;
size_t penvsz;
int flags;
/* Blocking would be nice, but it's not mandatory. */
flags = fcntl(infd, F_GETFL);
if (flags != -1 && (flags & O_NONBLOCK) != 0) {
flags &= ~O_NONBLOCK;
(void)fcntl(infd, F_SETFL, flags);
}
if (!daemon_await_prexfer_env_read(infd, &penvsz, sizeof(penvsz)))
_exit(1);
penv = malloc(penvsz);
if (penv == NULL)
_exit(1);
if (!daemon_await_prexfer_env_read(infd, penv, penvsz))
_exit(1);
close(infd);
infd = -1;
*obufsz = penvsz;
return penv;
}
static int
daemon_do_execcmds_pre(struct sess *sess, const char *module, const char *cmd)
{
struct daemon_role *role;
uint8_t *penv;
size_t penvsz;
int fd[2], status;
pid_t pid, ppid;
role = (void *)sess->role;
ppid = getpid();
if (pipe(&fd[0]) == -1)
goto stagefail;
pid = fork();
if (pid == -1)
goto stagefail;
if (pid != 0) {
/* Parent returns, carries on with startup */
close(fd[0]);
role->prexfer_pipe = fd[1];
role->prexfer_pid = pid;
return 1;
}
/* Child awaits environmental information. */
close(fd[1]);
/*
* The reference rsync seems to put this in both the parent and child
* environments if the pre-xfer exec command is set, but it's not clear
* why. We'll keep the transfer process's environment clean to match
* the post-xfer exec handling until we come up with a compelling reason
* to do otherwise (e.g., config vars that might expect RSYNC_PID to be
* populated -- this version of rsync does not yet do var expansion).
*/
daemon_do_execcmds_num_env("RSYNC_PID", ppid);
daemon_do_execcmds_common_env(role, module);
penv = daemon_await_prexfer_env(role, fd[0], &penvsz);
if (penv != NULL) {
char envname[sizeof("RSYNC_ARG") + 6];
const uint8_t *args, *endp, *narg;
int ret;
setenv("RSYNC_ARG0", "rsyncd", 1);
narg = args = penv;
for (size_t i = 0; penvsz != 0; i++) {
/*
* This should always be NUL-terminated, so we shouldn't
* have anything remaining if we hit endp == NULL.
*/
endp = memchr(narg, '\0', penvsz);
if (endp == NULL)
break;
/*
* The first one is actually the request. We took out
* RSYNC_ARG0 above with "rsyncd", but we make up for
* it here by stuffing it into RSYNC_REQUEST.
*/
if (i == 0) {
ret = (int)strlcpy(envname, "RSYNC_REQUEST",
sizeof(envname));
} else {
/* Add it */
ret = snprintf(envname, sizeof(envname),
"RSYNC_ARG%ld", i);
if (ret == -1)
break;
}
/* It should have been wide enough... */
assert(ret < (int)sizeof(envname));
(void)setenv(envname, (const char *)narg, 1);
endp++;
penvsz -= endp - narg;
narg = endp;
}
free(penv);
}
/* Environment is set, let's exec it! */
close(STDIN_FILENO);
close(STDOUT_FILENO);
status = system(cmd);
if (WIFEXITED(status))
status = WEXITSTATUS(status);
else
status = 1;
_exit(status);
stagefail:
daemon_client_error(sess, "%s: failed to stage pre-xfer process",
module);
return 0;
}
static int
daemon_do_execcmds_post(struct sess *sess, const char *module, const char *cmd)
{
pid_t pid, ret;
int status;
pid = fork();
if (pid == -1) {
daemon_client_error(sess, "%s: failed to fork for post-xfer");
return 0;
}
/* Child returns */
if (pid == 0)
return 1;
/* Parent waits */
daemon_do_execcmds_common_env((void *)sess->role, module);
daemon_do_execcmds_num_env("RSYNC_PID", pid);
while ((ret = waitpid(pid, &status, 0)) == -1 &&
errno == EINTR) {
continue; /* Spin */
}
if (ret != pid)
status = -1;
daemon_do_execcmds_num_env("RSYNC_RAW_STATUS", status);
if (WIFEXITED(status))
status = WEXITSTATUS(status);
else
status = -1;
daemon_do_execcmds_num_env("RSYNC_EXIT_STATUS", status);
/* Execute the command, but propagate the child status either way. */
system(cmd);
_exit(status);
}
int
daemon_do_execcmds(struct sess *sess, const char *module)
{
struct daemon_role *role;
const char *cmd;
int rc;
role = (void *)sess->role;
if (!cfg_has_param(role->dcfg, module, "pre-xfer exec") &&
!cfg_has_param(role->dcfg, module, "post-xfer exec"))
return 1;
/*
* We fire up the post-xfer exec command first because it will run in
* our current process and fork off a process to actually handle the
* transfer to reliably grab the final status. Thus, to be able to
* provide a consistent RSYNC_PID to both commands, we need this one to
* fork first -- the other one will fork and handle its command in the
* child instead.
*/
if (cfg_has_param(role->dcfg, module, "post-xfer exec")) {
rc = cfg_param_str(role->dcfg, module, "post-xfer exec", &cmd);
assert(rc == 0);
if (*cmd != '\0' && !daemon_do_execcmds_post(sess, module, cmd))
return 0;
}
if (cfg_has_param(role->dcfg, module, "pre-xfer exec")) {
rc = cfg_param_str(role->dcfg, module, "pre-xfer exec", &cmd);
assert(rc == 0);
if (*cmd != '\0' && !daemon_do_execcmds_pre(sess, module, cmd))
return 0;
}
return 1;
}
static int
daemon_finish_prexfer_write(int outfd, const void *bufp, size_t bufsz)
{
const uint8_t *buf = bufp;
size_t offset;
ssize_t wsz;
offset = 0;
while (bufsz != 0) {
wsz = write(outfd, &buf[offset], bufsz);
if (wsz <= 0) {
if (wsz == -1 && errno == EINTR)
continue;
else if (wsz == -1)
ERR("write");
return 0;
}
offset += wsz;
bufsz -= wsz;
}
return 1;
}
int
daemon_finish_prexfer(struct sess *sess, const char *req, const char *args,
size_t argsz)
{
struct daemon_role *role;
size_t reqsz, totalsz;
pid_t child, ret;
int fd, status;
bool error;
role = (void *)sess->role;
child = role->prexfer_pid;
fd = role->prexfer_pipe;