Files

631 lines
13 KiB
C

/*
* ser2net - A program for allowing telnet connection to serial ports
* Copyright (C) 2001 Corey Minyard <minyard@acm.org>
*
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* This file holds basic utilities used by the ser2net program. */
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <ctype.h>
#include "ser2net.h"
#include "utils.h"
#include "selector.h"
#include "locking.h"
int
strisallzero(char *str)
{
if (*str == '\0')
return 0;
while (*str == '0')
str++;
return *str == '\0';
}
/* Scan for a positive integer, and return it. Return -1 if the
integer was invalid. */
int
scan_int(char *str)
{
int rv = 0;
if (*str == '\0') {
return -1;
}
for (;;) {
switch (*str) {
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
rv = (rv * 10) + ((*str) - '0');
break;
case '\0':
return rv;
default:
return -1;
}
str++;
}
return rv;
}
/* Scan for a network port in the form "[hostname,]x", where the optional
first part is a resolvable hostname, an IPv4 octet, or an IPv6 address.
In the absence of a host specification, a wildcard address is used.
The mandatory second part is the port number or a service name. */
int
scan_network_port(const char *str, struct addrinfo **rai, bool *is_dgram,
bool *is_port_set)
{
char *strtok_data, *strtok_buffer;
char *ip;
char *port;
struct addrinfo hints, *ai;
int family = AF_UNSPEC;
int socktype = SOCK_STREAM;
if (strncmp(str, "ipv4,", 5) == 0) {
family = AF_INET;
str += 5;
} else if (strncmp(str, "ipv6,", 5) == 0) {
family = AF_INET6;
str += 5;
}
if (strncmp(str, "tcp,", 4) == 0) {
str += 4;
} else if (strncmp(str, "udp,", 4) == 0) {
/* Only allow UDP if asked for. */
if (!is_dgram)
return EINVAL;
socktype = SOCK_DGRAM;
str += 4;
}
strtok_buffer = strdup(str);
if (!strtok_buffer)
return ENOMEM;
ip = strtok_r(strtok_buffer, ",", &strtok_data);
port = strtok_r(NULL, "", &strtok_data);
if (port == NULL) {
port = ip;
ip = NULL;
}
memset(&hints, 0, sizeof(hints));
hints.ai_flags = AI_PASSIVE;
hints.ai_family = family;
hints.ai_socktype = socktype;
if (getaddrinfo(ip, port, &hints, &ai)) {
free(strtok_buffer);
return EINVAL;
}
if (is_dgram)
*is_dgram = socktype == SOCK_DGRAM;
if (is_port_set)
*is_port_set = !strisallzero(port);
free(strtok_buffer);
if (*rai)
freeaddrinfo(*rai);
*rai = ai;
return 0;
}
bool
sockaddr_equal(struct sockaddr *a1, socklen_t l1,
struct sockaddr *a2, socklen_t l2,
bool compare_ports)
{
if (l1 != l2)
return false;
if (a1->sa_family != a2->sa_family)
return false;
switch (a1->sa_family) {
case AF_INET:
{
struct sockaddr_in *s1 = (struct sockaddr_in *) a1;
struct sockaddr_in *s2 = (struct sockaddr_in *) a2;
if (compare_ports && s1->sin_port != s2->sin_port)
return false;
if (s1->sin_addr.s_addr != s2->sin_addr.s_addr)
return false;
}
break;
case AF_INET6:
{
struct sockaddr_in6 *s1 = (struct sockaddr_in6 *) a1;
struct sockaddr_in6 *s2 = (struct sockaddr_in6 *) a2;
if (compare_ports && s1->sin6_port != s2->sin6_port)
return false;
if (memcmp(s1->sin6_addr.s6_addr, s2->sin6_addr.s6_addr,
sizeof(s1->sin6_addr.s6_addr)) != 0)
return false;
}
break;
default:
/* Unknown family. */
return false;
}
return true;
}
void
check_ipv6_only(int family, struct sockaddr *addr, int fd)
{
if ((family == AF_INET6)
&& IN6_IS_ADDR_UNSPECIFIED(&(((struct sockaddr_in6 *) addr)->sin6_addr)))
{
int null = 0;
setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &null, sizeof(null));
}
}
struct opensocks *
open_socket(struct addrinfo *ai, void (*readhndlr)(int, void *),
void (*writehndlr)(int, void *), void *data,
unsigned int *nr_fds, void (*fd_handler_cleared)(int, void *))
{
struct addrinfo *rp;
int optval = 1;
int family = AF_INET6; /* Try IPV6 first, then IPV4. */
struct opensocks *fds;
unsigned int curr_fd = 0;
unsigned int max_fds = 0;
for (rp = ai; rp != NULL; rp = rp->ai_next)
max_fds++;
if (max_fds == 0)
return NULL;
fds = malloc(sizeof(*fds) * max_fds);
if (!fds)
return NULL;
restart:
for (rp = ai; rp != NULL; rp = rp->ai_next) {
if (family != rp->ai_family)
continue;
fds[curr_fd].fd = socket(rp->ai_family, rp->ai_socktype,
rp->ai_protocol);
if (fds[curr_fd].fd == -1)
continue;
fds[curr_fd].family = rp->ai_family;
if (fcntl(fds[curr_fd].fd, F_SETFL, O_NONBLOCK) == -1)
goto next;
if (setsockopt(fds[curr_fd].fd, SOL_SOCKET, SO_REUSEADDR,
(void *)&optval, sizeof(optval)) == -1)
goto next;
check_ipv6_only(rp->ai_family, rp->ai_addr, fds[curr_fd].fd);
if (bind(fds[curr_fd].fd, rp->ai_addr, rp->ai_addrlen) != 0)
goto next;
if (rp->ai_socktype == SOCK_STREAM && listen(fds[curr_fd].fd, 1) != 0)
goto next;
sel_set_fd_handlers(ser2net_sel, fds[curr_fd].fd, data,
readhndlr, writehndlr, NULL, fd_handler_cleared);
sel_set_fd_read_handler(ser2net_sel, fds[curr_fd].fd,
SEL_FD_HANDLER_ENABLED);
curr_fd++;
continue;
next:
close(fds[curr_fd].fd);
}
if (family == AF_INET6) {
family = AF_INET;
goto restart;
}
if (curr_fd == 0) {
free(fds);
fds = NULL;
}
*nr_fds = curr_fd;
return fds;
}
int
net_write(int fd, const void *buf, size_t len, int flags,
const struct sockaddr *addr, socklen_t addrlen)
{
if (addr)
return sendto(fd, buf, len, flags, addr, addrlen);
else
return write(fd, buf, len);
}
int
write_full(int fd, char *data, size_t count)
{
ssize_t written;
restart:
while ((written = write(fd, data, count)) > 0) {
data += written;
count -= written;
}
if (written < 0) {
if (errno == EAGAIN)
goto restart;
return -1;
}
return 0;
}
void
write_ignore_fail(int fd, const char *data, size_t count)
{
ssize_t written;
while ((written = write(fd, data, count)) > 0) {
data += written;
count -= written;
}
}
void str_to_argv_free(int argc, char **argv)
{
int i;
if (!argv)
return;
for (i = 0; i < argc; i++) {
if (argv[i])
free(argv[i]);
}
free(argv);
}
enum state {
in_space,
in_parm,
in_squote,
in_dquote,
in_bs, in_bs_hex, in_bs_hex2, in_bs_oct2, in_bs_oct3
};
static int add_to_parm(char **parm, size_t *parmlen, size_t *parmpos, char c)
{
if (*parmpos >= *parmlen) {
char *new_parm = realloc(*parm, *parmlen + 10);
if (!new_parm)
return ENOMEM;
*parmlen += 10;
*parm = new_parm;
}
(*parm)[*parmpos] = c;
(*parmpos)++;
return 0;
}
static int add_parm(int *argc, int *argc_max, char ***argv,
char *parm, size_t len)
{
char *s;
if (*argc >= *argc_max) {
char **new_argv = realloc(*argv, *argc_max + (10 * sizeof(char *)));
if (!new_argv)
return ENOMEM;
*argv = new_argv;
*argc_max += 10;
}
s = malloc(len + 1);
if (!s)
return ENOMEM;
memcpy(s, parm, len);
s[len] = '\0';
(*argv)[*argc] = s;
(*argc)++;
return 0;
}
int fromxdigit(char c)
{
if (c >= '0' && c <= '9')
return c - '0';
else if (c >= 'a' && c <= 'f')
return c - 'a' + 10;
else
return c - 'A' + 10;
}
int str_to_argv(const char *s, int *r_argc, char ***r_argv, char *seps)
{
int argc = 0;
int argc_max = 0;
char **argv = NULL;
enum state state, prev_state = in_parm, prev_bs_state = in_parm;
char *parm = NULL;
size_t parmlen = 0;
size_t parmpos = 0;
int rv = 0;
int c = 0;
if (!seps)
seps = " \f\n\r\t\v";
state = in_space;
for (; *s; s++) {
switch (state) {
case in_space:
if (strchr(seps, *s))
break;
parmpos = 0;
if (*s == '\'') {
prev_state = state;
state = in_squote;
} else if (*s == '"') {
prev_state = state;
state = in_dquote;
} else if (*s == '\\') {
prev_bs_state = state;
state = in_bs;
} else {
rv = add_to_parm(&parm, &parmlen, &parmpos, *s);
if (rv)
goto err;
state = in_parm;
}
break;
case in_parm:
if (strchr(seps, *s)) {
rv = add_parm(&argc, &argc_max, &argv, parm, parmpos);
if (rv)
goto err;
state = in_space;
} else if (*s == '\'') {
prev_state = state;
state = in_squote;
} else if (*s == '"') {
prev_state = state;
state = in_dquote;
} else if (*s == '\\') {
prev_bs_state = state;
state = in_bs;
} else {
rv = add_to_parm(&parm, &parmlen, &parmpos, *s);
if (rv)
goto err;
}
break;
case in_squote:
if (*s == '\'') {
state = prev_state;
} else if (*s == '\\') {
prev_bs_state = state;
state = in_bs;
} else {
rv = add_to_parm(&parm, &parmlen, &parmpos, *s);
if (rv)
goto err;
}
break;
case in_dquote:
if (*s == '"') {
state = prev_state;
} else if (*s == '\\') {
prev_bs_state = state;
state = in_bs;
} else {
rv = add_to_parm(&parm, &parmlen, &parmpos, *s);
if (rv)
goto err;
}
break;
case in_bs:
switch (*s) {
case '\\': c = '\\'; break;
case 'a': c = '\a'; break;
case 'b': c = '\b'; break;
case 'e': c = '\e'; break;
case 'f': c = '\f'; break;
case 'n': c = '\n'; break;
case 'r': c = '\r'; break;
case 't': c = '\t'; break;
case 'v': c = '\v'; break;
case 'x':
c = 0;
state = in_bs_hex;
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
c = *s - '0';
if (*(s + 1) >= '0' && *(s + 1) <= '7')
state = in_bs_oct2;
else
goto add_parm_c;
break;
}
if (state == in_bs)
goto add_parm_c;
break;
case in_bs_hex:
if (!isxdigit(*s)) {
rv = -EINVAL;
goto err;
}
c = fromxdigit(*s);
if (isxdigit(*(s + 1)))
state = in_bs_hex2;
else
goto add_parm_c;
break;
case in_bs_hex2:
c = (c * 16) + fromxdigit(*s);
goto add_parm_c;
case in_bs_oct2:
c = (c * 8) + (*s - '0');
if (*(s + 1) >= '0' && *(s + 1) <= '7')
state = in_bs_oct3;
else
goto add_parm_c;
break;
case in_bs_oct3:
c = (c * 8) + (*s - '0');
goto add_parm_c;
}
continue;
add_parm_c:
rv = add_to_parm(&parm, &parmlen, &parmpos, c);
if (rv)
goto err;
state = prev_bs_state;
}
switch (state) {
case in_space:
break;
case in_parm:
rv = add_parm(&argc, &argc_max, &argv, parm, parmpos);
break;
default:
rv = -EINVAL;
}
err:
free(parm);
if (rv) {
str_to_argv_free(argc, argv);
} else {
*r_argc = argc;
*r_argv = argv;
}
return rv;
}
#include <assert.h>
#ifdef USE_PTHREADS
struct waiter_s {
int set;
pthread_mutex_t lock;
pthread_cond_t cond;
};
waiter_t *alloc_waiter(void)
{
waiter_t *waiter;
waiter = malloc(sizeof(waiter_t));
if (waiter) {
memset(waiter, 0, sizeof(*waiter));
pthread_mutex_init(&waiter->lock, NULL);
pthread_cond_init(&waiter->cond, NULL);
}
return waiter;
}
void free_waiter(waiter_t *waiter)
{
assert(waiter);
assert(waiter->set == 0);
pthread_mutex_destroy(&waiter->lock);
pthread_cond_destroy(&waiter->cond);
free(waiter);
}
void wait_for_waiter(waiter_t *waiter)
{
pthread_mutex_lock(&waiter->lock);
if (!waiter->set)
pthread_cond_wait(&waiter->cond, &waiter->lock);
waiter->set = 0;
pthread_mutex_unlock(&waiter->lock);
}
void wake_waiter(waiter_t *waiter)
{
pthread_mutex_lock(&waiter->lock);
pthread_cond_signal(&waiter->cond);
waiter->set = 1;
pthread_mutex_unlock(&waiter->lock);
}
#else
struct waiter_s {
int set;
};
waiter_t *alloc_waiter(void)
{
waiter_t *waiter;
waiter = malloc(sizeof(waiter_t));
if (waiter)
memset(waiter, 0, sizeof(*waiter));
return waiter;
}
void free_waiter(waiter_t *waiter)
{
assert(waiter);
assert(waiter->set == 0);
free(waiter);
}
void wait_for_waiter(waiter_t *waiter)
{
assert(waiter->set == 1);
waiter->set = 0;
}
void wake_waiter(waiter_t *waiter)
{
waiter->set = 1;
}
#endif