/*
* Copyright (C) 2013-2016 Nikos Mavrogiannopoulos
* Copyright (C) 2016 Red Hat, Inc.
*
* 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 2 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, see .
*/
#include
#include
#include
#include
#include
#include
#include
#include
#include
/* for recvmsg */
#include
#include
#include
#include
#include
#include
#include "common.h"
#include "defs.h"
#include "common/base64-helper.h"
int saved_argc = 0;
char **saved_argv = NULL;
const char *_vhost_prefix(const char *name)
{
static char tmp[128];
snprintf(tmp, sizeof(tmp), "vhost:%s: ", name);
return tmp;
}
/* A hash of the input, to a 20-byte output. The goal is one-wayness.
*/
static void safe_hash(const uint8_t *data, unsigned data_size, uint8_t output[20])
{
struct sha1_ctx ctx;
sha1_init(&ctx);
sha1_update(&ctx, data_size, data);
sha1_digest(&ctx, 20, output);
}
char *calc_safe_id(const uint8_t *data, unsigned size, char *output, unsigned output_size)
{
uint8_t safe_id[20];
safe_hash(data, size, safe_id);
oc_base64_encode((char*)safe_id, 20, output, output_size);
return output;
}
/* Note that meaning slightly changes depending on whether we are
* referring to the cookie or the session itself.
*/
const char *ps_status_to_str(int status, unsigned cookie)
{
switch (status) {
case PS_AUTH_COMPLETED:
if (cookie)
return "authenticated";
else
return "connected";
case PS_AUTH_INIT:
case PS_AUTH_CONT:
return "authenticating";
case PS_AUTH_INACTIVE:
return "pre-auth";
case PS_AUTH_FAILED:
return "auth failed";
default:
return "unknown";
}
}
const char *cmd_request_to_str(unsigned _cmd)
{
cmd_request_t cmd = _cmd;
static char tmp[32];
switch (cmd) {
case AUTH_COOKIE_REP:
return "auth cookie reply";
case AUTH_COOKIE_REQ:
return "auth cookie request";
case RESUME_STORE_REQ:
return "resume data store request";
case RESUME_DELETE_REQ:
return "resume data delete request";
case RESUME_FETCH_REQ:
return "resume data fetch request";
case RESUME_FETCH_REP:
return "resume data fetch reply";
case CMD_UDP_FD:
return "udp fd";
case CMD_TUN_MTU:
return "tun mtu change";
case CMD_TERMINATE:
return "terminate";
case CMD_SESSION_INFO:
return "session info";
case CMD_BAN_IP:
return "ban IP";
case CMD_BAN_IP_REPLY:
return "ban IP reply";
case CMD_LATENCY_STATS_DELTA:
return "latency stats delta";
case CMD_SEC_CLI_STATS:
return "sm: worker cli stats";
case CMD_SEC_AUTH_INIT:
return "sm: auth init";
case CMD_SEC_AUTH_CONT:
return "sm: auth cont";
case CMD_SEC_AUTH_REPLY:
return "sm: auth rep";
case CMD_SEC_DECRYPT:
return "sm: decrypt";
case CMD_SEC_SIGN:
return "sm: sign";
case CMD_SEC_SIGN_DATA:
return "sm: sign data";
case CMD_SEC_SIGN_HASH:
return "sm: sign hash";
case CMD_SEC_GET_PK:
return "sm: get pk";
case CMD_SECM_SESSION_CLOSE:
return "sm: session close";
case CMD_SECM_SESSION_OPEN:
return "sm: session open";
case CMD_SECM_SESSION_REPLY:
return "sm: session reply";
case CMD_SECM_BAN_IP:
return "sm: ban IP";
case CMD_SECM_BAN_IP_REPLY:
return "sm: ban IP reply";
case CMD_SECM_CLI_STATS:
return "sm: main cli stats";
case CMD_SECM_LIST_COOKIES:
return "sm: list cookies";
case CMD_SECM_LIST_COOKIES_REPLY:
return "sm: list cookies reply";
case CMD_SECM_STATS:
return "sm: stats";
case CMD_SECM_RELOAD:
return "sm: reload";
case CMD_SECM_RELOAD_REPLY:
return "sm: reload reply";
default:
snprintf(tmp, sizeof(tmp), "unknown (%u)", _cmd);
return tmp;
}
}
const char *discon_reason_to_str(unsigned reason)
{
static char tmp[32];
switch (reason) {
case 0:
case REASON_ANY:
return "unspecified";
case REASON_USER_DISCONNECT:
return "user disconnected";
case REASON_TEMP_DISCONNECT:
return "anyconnect client disconnected";
case REASON_SERVER_DISCONNECT:
return "server disconnected";
case REASON_IDLE_TIMEOUT:
return "idle timeout";
case REASON_DPD_TIMEOUT:
return "DPD timeout";
case REASON_ERROR:
return "unspecified error";
case REASON_SESSION_TIMEOUT:
return "session timeout";
case REASON_HEALTH_PROBE:
return "TCP health probe";
default:
snprintf(tmp, sizeof(tmp), "unknown (%u)", reason);
return tmp;
}
}
unsigned int discon_reason_to_log_level(unsigned int reason)
{
switch (reason) {
case 0:
case REASON_ANY:
case REASON_HEALTH_PROBE:
return LOG_DEBUG;
case REASON_USER_DISCONNECT:
case REASON_TEMP_DISCONNECT:
case REASON_SERVER_DISCONNECT:
case REASON_IDLE_TIMEOUT:
case REASON_DPD_TIMEOUT:
case REASON_ERROR:
case REASON_SESSION_TIMEOUT:
default:
return LOG_INFO;
}
}
ssize_t force_write(int sockfd, const void *buf, size_t len)
{
int left = len;
int ret;
const uint8_t *p = buf;
while (left > 0) {
ret = write(sockfd, p, left);
if (ret == -1) {
if (errno != EAGAIN && errno != EINTR)
return ret;
else
ms_sleep(50);
}
if (ret > 0) {
left -= ret;
p += ret;
}
}
return len;
}
ssize_t force_read(int sockfd, void *buf, size_t len)
{
int left = len;
int ret;
uint8_t *p = buf;
while (left > 0) {
ret = read(sockfd, p, left);
if (ret == -1) {
if (errno != EAGAIN && errno != EINTR)
return ret;
} else if (ret == 0) {
assert(left != 0); /* ensured by the while */
errno = ENOENT;
return -1;
}
if (ret > 0) {
left -= ret;
p += ret;
}
}
return len;
}
ssize_t force_read_timeout(int sockfd, void *buf, size_t len, unsigned sec)
{
int left = len;
int ret;
uint8_t *p = buf;
struct pollfd pfd;
while (left > 0) {
if (sec > 0) {
pfd.fd = sockfd;
pfd.events = POLLIN;
pfd.revents = 0;
do {
ret = poll(&pfd, 1, sec * 1000);
} while (ret == -1 && errno == EINTR);
if (ret == -1 || ret == 0) {
errno = ETIMEDOUT;
return -1;
}
}
ret = read(sockfd, p, left);
if (ret == -1) {
if (errno != EAGAIN && errno != EINTR)
return ret;
} else if (ret == 0) {
assert(left != 0);
errno = ENOENT;
return -1;
}
if (ret > 0) {
left -= ret;
p += ret;
}
}
return len;
}
void set_non_block(int fd)
{
int val, ret;
val = fcntl(fd, F_GETFL, 0);
ret = fcntl(fd, F_SETFL, val | O_NONBLOCK);
if (ret == -1) {
/* We log but we do not fail; this seems to be failing when we test
* on 32-bit mode container over a 64-bit kernel. I believe this is related to that:
* https://patchwork.kernel.org/project/qemu-devel/patch/20200331133536.3328-1-linus.walleij@linaro.org/
*/
int e = errno;
syslog(LOG_ERR, "set_non_block: %s", strerror(e));
}
}
void set_block(int fd)
{
int val, ret;
val = fcntl(fd, F_GETFL, 0);
ret = fcntl(fd, F_SETFL, val & (~O_NONBLOCK));
if (ret == -1) {
int e = errno;
syslog(LOG_ERR, "set_non_block: %s", strerror(e));
}
}
ssize_t recv_timeout(int sockfd, void *buf, size_t len, unsigned sec)
{
int ret;
struct pollfd pfd;
pfd.fd = sockfd;
pfd.events = POLLIN;
pfd.revents = 0;
do {
ret = poll(&pfd, 1, sec * 1000);
} while (ret == -1 && errno == EINTR);
if (ret == -1 || ret == 0) {
errno = ETIMEDOUT;
return -1;
}
return recv(sockfd, buf, len, 0);
}
ssize_t recvmsg_timeout(int sockfd, struct msghdr * msg, int flags,
unsigned sec)
{
int ret;
if (sec) {
struct pollfd pfd;
pfd.fd = sockfd;
pfd.events = POLLIN;
pfd.revents = 0;
do {
ret = poll(&pfd, 1, sec * 1000);
} while (ret == -1 && errno == EINTR);
if (ret == -1 || ret == 0) {
errno = ETIMEDOUT;
return -1;
}
}
do {
ret = recvmsg(sockfd, msg, flags);
} while (ret == -1 && errno == EINTR);
return ret;
}
int forward_msg(void *pool, int ifd, uint8_t icmd, int ofd, uint8_t ocmd, unsigned timeout)
{
struct iovec iov[3];
char data[5];
uint32_t length;
ssize_t left;
uint8_t rcmd;
struct msghdr hdr;
int ret;
iov[0].iov_base = &rcmd;
iov[0].iov_len = 1;
iov[1].iov_base = &length;
iov[1].iov_len = 4;
memset(&hdr, 0, sizeof(hdr));
hdr.msg_iov = iov;
hdr.msg_iovlen = 2;
ret = recvmsg_timeout(ifd, &hdr, 0, timeout);
if (ret == -1) {
int e = errno;
syslog(LOG_ERR, "%s:%u: recvmsg: %s", __FILE__, __LINE__,
strerror(e));
return ERR_BAD_COMMAND;
}
if (ret == 0) {
return ERR_PEER_TERMINATED;
}
if (rcmd != icmd) {
syslog(LOG_ERR, "%s:%u: expected %d, received %d", __FILE__,
__LINE__, (int)rcmd, (int)icmd);
return ERR_BAD_COMMAND;
}
data[0] = ocmd;
memcpy(&data[1], &length, 4);
/* send headers */
ret = force_write(ofd, data, 5);
if (ret != 5) {
syslog(LOG_ERR, "%s:%u: cannot send headers: %s", __FILE__,
__LINE__, strerror(errno));
return ERR_BAD_COMMAND;
}
left = length;
while (left > 0) {
char buf[1024];
ret = recv(ifd, buf, sizeof(buf), 0);
if (ret == -1 || ret == 0) {
if (errno == EAGAIN || errno == EINTR)
continue;
syslog(LOG_ERR, "%s:%u: cannot send between descriptors: %s", __FILE__,
__LINE__, strerror(errno));
return ERR_BAD_COMMAND;
}
ret = force_write(ofd, buf, ret);
if (ret == -1 || ret == 0) {
syslog(LOG_ERR, "%s:%u: cannot send between descriptors: %s", __FILE__,
__LINE__, strerror(errno));
return ERR_BAD_COMMAND;
}
left -= ret;
}
return 0;
}
/* Sends message + socketfd */
int send_socket_msg(void *pool, int fd, uint8_t cmd,
int socketfd, const void *msg,
pack_size_func get_size, pack_func pack)
{
struct iovec iov[3];
struct msghdr hdr;
union {
struct cmsghdr cm;
char control[CMSG_SPACE(sizeof(int))];
} control_un;
struct cmsghdr *cmptr;
void *packed = NULL;
uint32_t length32;
size_t length = 0;
int ret;
memset(&hdr, 0, sizeof(hdr));
iov[0].iov_base = &cmd;
iov[0].iov_len = 1;
if (msg)
length = get_size(msg);
if (length >= UINT32_MAX)
return -1;
length32 = length;
iov[1].iov_base = &length32;
iov[1].iov_len = 4;
hdr.msg_iov = iov;
hdr.msg_iovlen = 2;
if (length > 0) {
packed = talloc_size(pool, length);
if (packed == NULL) {
syslog(LOG_ERR, "%s:%u: memory error", __FILE__,
__LINE__);
return -1;
}
iov[2].iov_base = packed;
iov[2].iov_len = length;
ret = pack(msg, packed);
if (ret == 0) {
syslog(LOG_ERR, "%s:%u: packing error", __FILE__,
__LINE__);
ret = -1;
goto cleanup;
}
hdr.msg_iovlen++;
}
if (socketfd != -1) {
hdr.msg_control = control_un.control;
hdr.msg_controllen = sizeof(control_un.control);
cmptr = CMSG_FIRSTHDR(&hdr);
cmptr->cmsg_len = CMSG_LEN(sizeof(int));
cmptr->cmsg_level = SOL_SOCKET;
cmptr->cmsg_type = SCM_RIGHTS;
memcpy(CMSG_DATA(cmptr), &socketfd, sizeof(int));
}
do {
ret = sendmsg(fd, &hdr, 0);
} while (ret == -1 && errno == EINTR);
if (ret < 0) {
int e = errno;
syslog(LOG_ERR, "%s:%u: %s", __FILE__, __LINE__, strerror(e));
}
cleanup:
if (length > 0)
safe_memset(packed, 0, length);
talloc_free(packed);
return ret;
}
int recv_msg_headers(int fd, uint8_t *cmd, unsigned timeout)
{
struct iovec iov[3];
char buffer[5];
uint32_t l32;
struct msghdr hdr;
int ret;
iov[0].iov_base = buffer;
iov[0].iov_len = 5;
memset(&hdr, 0, sizeof(hdr));
hdr.msg_iov = iov;
hdr.msg_iovlen = 1;
ret = recvmsg_timeout(fd, &hdr, 0, timeout);
if (ret == -1) {
int e = errno;
syslog(LOG_WARNING, "%s:%u: recvmsg: %s", __FILE__, __LINE__,
strerror(e));
return ERR_BAD_COMMAND;
}
if (ret == 0) {
return ERR_PEER_TERMINATED;
}
*cmd = buffer[0];
memcpy(&l32, &buffer[1], 4);
return l32;
}
int recv_msg_data(int fd, uint8_t *cmd, uint8_t *data, size_t data_size,
int *received_fd)
{
struct iovec iov[3];
uint32_t l32;
struct msghdr hdr;
union {
struct cmsghdr cm;
char control[CMSG_SPACE(sizeof(int))];
} control_un;
struct cmsghdr *cmptr;
int ret;
iov[0].iov_base = cmd;
iov[0].iov_len = 1;
iov[1].iov_base = &l32;
iov[1].iov_len = 4;
memset(&hdr, 0, sizeof(hdr));
hdr.msg_iov = iov;
hdr.msg_iovlen = 2;
hdr.msg_control = control_un.control;
hdr.msg_controllen = sizeof(control_un.control);
ret = recvmsg_timeout(fd, &hdr, 0, MAIN_SEC_MOD_TIMEOUT);
if (ret == -1) {
int e = errno;
syslog(LOG_ERR, "%s:%u: recvmsg: %s", __FILE__, __LINE__,
strerror(e));
return ERR_BAD_COMMAND;
}
if (ret == 0) {
return ERR_PEER_TERMINATED;
}
/* try to receive socket (if any) */
if (received_fd != NULL) {
*received_fd = -1;
if ((cmptr = CMSG_FIRSTHDR(&hdr)) != NULL
&& cmptr->cmsg_len == CMSG_LEN(sizeof(int))) {
if (cmptr->cmsg_level != SOL_SOCKET
|| cmptr->cmsg_type != SCM_RIGHTS) {
syslog(LOG_ERR,
"%s:%u: recvmsg returned invalid msg type",
__FILE__, __LINE__);
return ERR_BAD_COMMAND;
}
if (CMSG_DATA(cmptr))
memcpy(received_fd, CMSG_DATA(cmptr), sizeof(int));
}
}
if (l32 > data_size) {
syslog(LOG_ERR, "%s:%u: recv_msg_data: received more data than expected", __FILE__,
__LINE__);
ret = ERR_BAD_COMMAND;
goto cleanup;
}
ret = force_read_timeout(fd, data, l32, MAIN_SEC_MOD_TIMEOUT);
if (ret < l32) {
int e = errno;
syslog(LOG_ERR, "%s:%u: recvmsg: %s", __FILE__,
__LINE__, strerror(e));
ret = ERR_BAD_COMMAND;
goto cleanup;
}
ret = l32;
cleanup:
if (ret < 0 && received_fd != NULL && *received_fd != -1) {
close(*received_fd);
*received_fd = -1;
}
return ret;
}
int recv_socket_msg(void *pool, int fd, uint8_t cmd,
int *socketfd, void **msg, unpack_func unpack,
unsigned timeout)
{
struct iovec iov[3];
uint32_t length;
uint8_t rcmd;
struct msghdr hdr;
uint8_t *data = NULL;
union {
struct cmsghdr cm;
char control[CMSG_SPACE(sizeof(int))];
} control_un;
struct cmsghdr *cmptr;
int ret;
PROTOBUF_ALLOCATOR(pa, pool);
iov[0].iov_base = &rcmd;
iov[0].iov_len = 1;
iov[1].iov_base = &length;
iov[1].iov_len = 4;
memset(&hdr, 0, sizeof(hdr));
hdr.msg_iov = iov;
hdr.msg_iovlen = 2;
hdr.msg_control = control_un.control;
hdr.msg_controllen = sizeof(control_un.control);
ret = recvmsg_timeout(fd, &hdr, 0, timeout);
if (ret == -1) {
int e = errno;
syslog(LOG_ERR, "%s:%u: recvmsg: %s", __FILE__, __LINE__,
strerror(e));
return ERR_BAD_COMMAND;
}
if (ret == 0) {
return ERR_PEER_TERMINATED;
}
if (rcmd != cmd) {
syslog(LOG_ERR, "%s:%u: expected %d, received %d", __FILE__,
__LINE__, (int)rcmd, (int)cmd);
return ERR_BAD_COMMAND;
}
/* try to receive socket (if any) */
if (socketfd != NULL) {
if ((cmptr = CMSG_FIRSTHDR(&hdr)) != NULL
&& cmptr->cmsg_len == CMSG_LEN(sizeof(int))) {
if (cmptr->cmsg_level != SOL_SOCKET
|| cmptr->cmsg_type != SCM_RIGHTS) {
syslog(LOG_ERR,
"%s:%u: recvmsg returned invalid msg type",
__FILE__, __LINE__);
return ERR_BAD_COMMAND;
}
if (CMSG_DATA(cmptr))
memcpy(socketfd, CMSG_DATA(cmptr), sizeof(int));
else
*socketfd = -1;
} else {
*socketfd = -1;
}
}
if (length > 0 && msg) {
data = talloc_size(pool, length);
if (data == NULL) {
ret = ERR_MEM;
goto cleanup;
}
ret = force_read_timeout(fd, data, length, timeout);
if (ret < length) {
int e = errno;
syslog(LOG_ERR, "%s:%u: recvmsg: %s", __FILE__,
__LINE__, strerror(e));
ret = ERR_BAD_COMMAND;
goto cleanup;
}
*msg = unpack(&pa, length, data);
if (*msg == NULL) {
syslog(LOG_ERR, "%s:%u: unpacking error", __FILE__,
__LINE__);
ret = ERR_MEM;
goto cleanup;
}
}
ret = 0;
cleanup:
talloc_free(data);
if (ret < 0 && socketfd != NULL && *socketfd != -1) {
close(*socketfd);
*socketfd = -1;
}
return ret;
}
void _talloc_free2(void *ctx, void *ptr)
{
talloc_free(ptr);
}
void *_talloc_size2(void *ctx, size_t size)
{
return talloc_size(ctx, size);
}
/* like recvfrom but also returns the address of our interface.
*
* @def_port: is provided to fill in the missing port number
* in our_addr.
*/
ssize_t oc_recvfrom_at(int sockfd, void *buf, size_t len, int flags,
struct sockaddr * src_addr, socklen_t * addrlen,
struct sockaddr * our_addr, socklen_t * our_addrlen,
int def_port)
{
int ret;
char cmbuf[256];
struct iovec iov = { buf, len };
struct cmsghdr *cmsg;
struct msghdr mh = {
.msg_name = src_addr,
.msg_namelen = *addrlen,
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_control = cmbuf,
.msg_controllen = sizeof(cmbuf),
};
do {
ret = recvmsg(sockfd, &mh, 0);
} while (ret == -1 && errno == EINTR);
if (ret < 0) {
return -1;
}
/* find our address */
for (cmsg = CMSG_FIRSTHDR(&mh); cmsg != NULL;
cmsg = CMSG_NXTHDR(&mh, cmsg)) {
#if defined(IP_PKTINFO)
if (cmsg->cmsg_level == IPPROTO_IP
&& cmsg->cmsg_type == IP_PKTINFO) {
struct in_pktinfo *pi = (void *)CMSG_DATA(cmsg);
struct sockaddr_in *a = (struct sockaddr_in *)our_addr;
if (*our_addrlen < sizeof(struct sockaddr_in)
|| pi == NULL)
return -1;
a->sin_family = AF_INET;
memcpy(&a->sin_addr, &pi->ipi_addr,
sizeof(struct in_addr));
a->sin_port = htons(def_port);
*our_addrlen = sizeof(struct sockaddr_in);
break;
}
#elif defined(IP_RECVDSTADDR)
if (cmsg->cmsg_level == IPPROTO_IP
&& cmsg->cmsg_type == IP_RECVDSTADDR) {
struct in_addr *pi = (void *)CMSG_DATA(cmsg);
struct sockaddr_in *a = (struct sockaddr_in *)our_addr;
if (*our_addrlen < sizeof(struct sockaddr_in)
|| pi == NULL)
return -1;
a->sin_family = AF_INET;
memcpy(&a->sin_addr, &pi->s_addr,
sizeof(struct in_addr));
a->sin_port = htons(def_port);
*our_addrlen = sizeof(struct sockaddr_in);
break;
}
#endif
#ifdef IPV6_RECVPKTINFO
if (cmsg->cmsg_level == IPPROTO_IPV6
&& cmsg->cmsg_type == IPV6_PKTINFO) {
struct in6_pktinfo *pi = (void *)CMSG_DATA(cmsg);
struct sockaddr_in6 *a =
(struct sockaddr_in6 *)our_addr;
if (*our_addrlen < sizeof(struct sockaddr_in6)
|| pi == NULL)
return -1;
a->sin6_family = AF_INET6;
memcpy(&a->sin6_addr, &pi->ipi6_addr,
sizeof(struct in6_addr));
a->sin6_port = htons(def_port);
*our_addrlen = sizeof(struct sockaddr_in6);
break;
}
#endif
}
*addrlen = mh.msg_namelen;
return ret;
}
#ifndef HAVE_STRLCPY
/*
* Copyright (c) 1998 Todd C. Miller
*
* 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.
*
* Copyright 2006 The FreeRADIUS server project
*/
/*
* Copy src to string dst of size siz. At most siz-1 characters
* will be copied. Always NUL terminates (unless siz == 0).
* Returns strlen(src); if retval >= siz, truncation occurred.
*/
size_t oc_strlcpy(char *dst, char const *src, size_t siz)
{
char *d = dst;
char const *s = src;
size_t n = siz;
/* Copy as many bytes as will fit */
if (n != 0 && --n != 0) {
do {
if ((*d++ = *s++) == 0)
break;
} while (--n != 0);
}
/* Not enough room in dst, add NUL and traverse rest of src */
if (n == 0) {
if (siz != 0)
*d = '\0'; /* NUL-terminate dst */
while (*s++) ;
}
return (s - src - 1); /* count does not include NUL */
}
#endif