freebsd-nq/crypto/heimdal/kdc/connect.c
2005-02-24 22:22:53 +00:00

811 lines
19 KiB
C

/*
* Copyright (c) 1997-2004 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "kdc_locl.h"
RCSID("$Id: connect.c,v 1.90.2.2 2004/04/02 20:50:53 lha Exp $");
/*
* a tuple describing on what to listen
*/
struct port_desc{
int family;
int type;
int port;
};
/* the current ones */
static struct port_desc *ports;
static int num_ports;
/*
* add `family, port, protocol' to the list with duplicate suppresion.
*/
static void
add_port(int family, int port, const char *protocol)
{
int type;
int i;
if(strcmp(protocol, "udp") == 0)
type = SOCK_DGRAM;
else if(strcmp(protocol, "tcp") == 0)
type = SOCK_STREAM;
else
return;
for(i = 0; i < num_ports; i++){
if(ports[i].type == type
&& ports[i].port == port
&& ports[i].family == family)
return;
}
ports = realloc(ports, (num_ports + 1) * sizeof(*ports));
if (ports == NULL)
krb5_err (context, 1, errno, "realloc");
ports[num_ports].family = family;
ports[num_ports].type = type;
ports[num_ports].port = port;
num_ports++;
}
/*
* add a triple but with service -> port lookup
* (this prints warnings for stuff that does not exist)
*/
static void
add_port_service(int family, const char *service, int port,
const char *protocol)
{
port = krb5_getportbyname (context, service, protocol, port);
add_port (family, port, protocol);
}
/*
* add the port with service -> port lookup or string -> number
* (no warning is printed)
*/
static void
add_port_string (int family, const char *port_str, const char *protocol)
{
struct servent *sp;
int port;
sp = roken_getservbyname (port_str, protocol);
if (sp != NULL) {
port = sp->s_port;
} else {
char *end;
port = htons(strtol(port_str, &end, 0));
if (end == port_str)
return;
}
add_port (family, port, protocol);
}
/*
* add the standard collection of ports for `family'
*/
static void
add_standard_ports (int family)
{
add_port_service(family, "kerberos", 88, "udp");
add_port_service(family, "kerberos", 88, "tcp");
add_port_service(family, "kerberos-sec", 88, "udp");
add_port_service(family, "kerberos-sec", 88, "tcp");
if(enable_http)
add_port_service(family, "http", 80, "tcp");
if(enable_524) {
add_port_service(family, "krb524", 4444, "udp");
add_port_service(family, "krb524", 4444, "tcp");
}
#ifdef KRB4
if(enable_v4) {
add_port_service(family, "kerberos-iv", 750, "udp");
add_port_service(family, "kerberos-iv", 750, "tcp");
}
if (enable_kaserver)
add_port_service(family, "afs3-kaserver", 7004, "udp");
#endif
}
/*
* parse the set of space-delimited ports in `str' and add them.
* "+" => all the standard ones
* otherwise it's port|service[/protocol]
*/
static void
parse_ports(const char *str)
{
char *pos = NULL;
char *p;
char *str_copy = strdup (str);
p = strtok_r(str_copy, " \t", &pos);
while(p != NULL) {
if(strcmp(p, "+") == 0) {
#ifdef HAVE_IPV6
add_standard_ports(AF_INET6);
#endif
add_standard_ports(AF_INET);
} else {
char *q = strchr(p, '/');
if(q){
*q++ = 0;
#ifdef HAVE_IPV6
add_port_string(AF_INET6, p, q);
#endif
add_port_string(AF_INET, p, q);
}else {
#ifdef HAVE_IPV6
add_port_string(AF_INET6, p, "udp");
add_port_string(AF_INET6, p, "tcp");
#endif
add_port_string(AF_INET, p, "udp");
add_port_string(AF_INET, p, "tcp");
}
}
p = strtok_r(NULL, " \t", &pos);
}
free (str_copy);
}
/*
* every socket we listen on
*/
struct descr {
int s;
int type;
unsigned char *buf;
size_t size;
size_t len;
time_t timeout;
struct sockaddr_storage __ss;
struct sockaddr *sa;
socklen_t sock_len;
char addr_string[128];
};
static void
init_descr(struct descr *d)
{
memset(d, 0, sizeof(*d));
d->sa = (struct sockaddr *)&d->__ss;
d->s = -1;
}
/*
* re-initialize all `n' ->sa in `d'.
*/
static void
reinit_descrs (struct descr *d, int n)
{
int i;
for (i = 0; i < n; ++i)
d[i].sa = (struct sockaddr *)&d[i].__ss;
}
/*
* Create the socket (family, type, port) in `d'
*/
static void
init_socket(struct descr *d, krb5_address *a, int family, int type, int port)
{
krb5_error_code ret;
struct sockaddr_storage __ss;
struct sockaddr *sa = (struct sockaddr *)&__ss;
int sa_size = sizeof(__ss);
init_descr (d);
ret = krb5_addr2sockaddr (context, a, sa, &sa_size, port);
if (ret) {
krb5_warn(context, ret, "krb5_addr2sockaddr");
close(d->s);
d->s = -1;
return;
}
if (sa->sa_family != family)
return;
d->s = socket(family, type, 0);
if(d->s < 0){
krb5_warn(context, errno, "socket(%d, %d, 0)", family, type);
d->s = -1;
return;
}
#if defined(HAVE_SETSOCKOPT) && defined(SOL_SOCKET) && defined(SO_REUSEADDR)
{
int one = 1;
setsockopt(d->s, SOL_SOCKET, SO_REUSEADDR, (void *)&one, sizeof(one));
}
#endif
d->type = type;
if(bind(d->s, sa, sa_size) < 0){
char a_str[256];
size_t len;
krb5_print_address (a, a_str, sizeof(a_str), &len);
krb5_warn(context, errno, "bind %s/%d", a_str, ntohs(port));
close(d->s);
d->s = -1;
return;
}
if(type == SOCK_STREAM && listen(d->s, SOMAXCONN) < 0){
char a_str[256];
size_t len;
krb5_print_address (a, a_str, sizeof(a_str), &len);
krb5_warn(context, errno, "listen %s/%d", a_str, ntohs(port));
close(d->s);
d->s = -1;
return;
}
}
/*
* Allocate descriptors for all the sockets that we should listen on
* and return the number of them.
*/
static int
init_sockets(struct descr **desc)
{
krb5_error_code ret;
int i, j;
struct descr *d;
int num = 0;
krb5_addresses addresses;
if (explicit_addresses.len) {
addresses = explicit_addresses;
} else {
ret = krb5_get_all_server_addrs (context, &addresses);
if (ret)
krb5_err (context, 1, ret, "krb5_get_all_server_addrs");
}
parse_ports(port_str);
d = malloc(addresses.len * num_ports * sizeof(*d));
if (d == NULL)
krb5_errx(context, 1, "malloc(%lu) failed",
(unsigned long)num_ports * sizeof(*d));
for (i = 0; i < num_ports; i++){
for (j = 0; j < addresses.len; ++j) {
init_socket(&d[num], &addresses.val[j],
ports[i].family, ports[i].type, ports[i].port);
if(d[num].s != -1){
char a_str[80];
size_t len;
krb5_print_address (&addresses.val[j], a_str,
sizeof(a_str), &len);
kdc_log(5, "listening on %s port %u/%s",
a_str,
ntohs(ports[i].port),
(ports[i].type == SOCK_STREAM) ? "tcp" : "udp");
/* XXX */
num++;
}
}
}
krb5_free_addresses (context, &addresses);
d = realloc(d, num * sizeof(*d));
if (d == NULL && num != 0)
krb5_errx(context, 1, "realloc(%lu) failed",
(unsigned long)num * sizeof(*d));
reinit_descrs (d, num);
*desc = d;
return num;
}
/*
* handle the request in `buf, len', from `addr' (or `from' as a string),
* sending a reply in `reply'.
*/
static int
process_request(unsigned char *buf,
size_t len,
krb5_data *reply,
int *sendlength,
const char *from,
struct sockaddr *addr)
{
KDC_REQ req;
Ticket ticket;
krb5_error_code ret;
size_t i;
gettimeofday(&now, NULL);
if(decode_AS_REQ(buf, len, &req, &i) == 0){
ret = as_rep(&req, reply, from, addr);
free_AS_REQ(&req);
return ret;
}else if(decode_TGS_REQ(buf, len, &req, &i) == 0){
ret = tgs_rep(&req, reply, from, addr);
free_TGS_REQ(&req);
return ret;
}else if(decode_Ticket(buf, len, &ticket, &i) == 0){
ret = do_524(&ticket, reply, from, addr);
free_Ticket(&ticket);
return ret;
#ifdef KRB4
} else if(maybe_version4(buf, len)){
*sendlength = 0; /* elbitapmoc sdrawkcab XXX */
do_version4(buf, len, reply, from, (struct sockaddr_in*)addr);
return 0;
} else if (enable_kaserver) {
ret = do_kaserver (buf, len, reply, from, (struct sockaddr_in*)addr);
return ret;
#endif
}
return -1;
}
static void
addr_to_string(struct sockaddr *addr, size_t addr_len, char *str, size_t len)
{
krb5_address a;
if(krb5_sockaddr2address(context, addr, &a) == 0) {
if(krb5_print_address(&a, str, len, &len) == 0) {
krb5_free_address(context, &a);
return;
}
krb5_free_address(context, &a);
}
snprintf(str, len, "<family=%d>", addr->sa_family);
}
/*
* Handle the request in `buf, len' to socket `d'
*/
static void
do_request(void *buf, size_t len, int sendlength,
struct descr *d)
{
krb5_error_code ret;
krb5_data reply;
reply.length = 0;
ret = process_request(buf, len, &reply, &sendlength,
d->addr_string, d->sa);
if(reply.length){
kdc_log(5, "sending %lu bytes to %s", (unsigned long)reply.length,
d->addr_string);
if(sendlength){
unsigned char len[4];
len[0] = (reply.length >> 24) & 0xff;
len[1] = (reply.length >> 16) & 0xff;
len[2] = (reply.length >> 8) & 0xff;
len[3] = reply.length & 0xff;
if(sendto(d->s, len, sizeof(len), 0, d->sa, d->sock_len) < 0) {
kdc_log (0, "sendto(%s): %s", d->addr_string, strerror(errno));
krb5_data_free(&reply);
return;
}
}
if(sendto(d->s, reply.data, reply.length, 0, d->sa, d->sock_len) < 0) {
kdc_log (0, "sendto(%s): %s", d->addr_string, strerror(errno));
krb5_data_free(&reply);
return;
}
krb5_data_free(&reply);
}
if(ret)
kdc_log(0, "Failed processing %lu byte request from %s",
(unsigned long)len, d->addr_string);
}
/*
* Handle incoming data to the UDP socket in `d'
*/
static void
handle_udp(struct descr *d)
{
unsigned char *buf;
int n;
buf = malloc(max_request);
if(buf == NULL){
kdc_log(0, "Failed to allocate %lu bytes", (unsigned long)max_request);
return;
}
d->sock_len = sizeof(d->__ss);
n = recvfrom(d->s, buf, max_request, 0, d->sa, &d->sock_len);
if(n < 0)
krb5_warn(context, errno, "recvfrom");
else {
addr_to_string (d->sa, d->sock_len,
d->addr_string, sizeof(d->addr_string));
do_request(buf, n, 0, d);
}
free (buf);
}
static void
clear_descr(struct descr *d)
{
if(d->buf)
memset(d->buf, 0, d->size);
d->len = 0;
if(d->s != -1)
close(d->s);
d->s = -1;
}
/* remove HTTP %-quoting from buf */
static int
de_http(char *buf)
{
char *p, *q;
for(p = q = buf; *p; p++, q++) {
if(*p == '%' && isxdigit(p[1]) && isxdigit(p[2])) {
unsigned int x;
if(sscanf(p + 1, "%2x", &x) != 1)
return -1;
*q = x;
p += 2;
} else
*q = *p;
}
*q = '\0';
return 0;
}
#define TCP_TIMEOUT 4
/*
* accept a new TCP connection on `d[parent]' and store it in `d[child]'
*/
static void
add_new_tcp (struct descr *d, int parent, int child)
{
int s;
if (child == -1)
return;
d[child].sock_len = sizeof(d[child].__ss);
s = accept(d[parent].s, d[child].sa, &d[child].sock_len);
if(s < 0) {
krb5_warn(context, errno, "accept");
return;
}
if (s >= FD_SETSIZE) {
krb5_warnx(context, "socket FD too large");
close (s);
return;
}
d[child].s = s;
d[child].timeout = time(NULL) + TCP_TIMEOUT;
d[child].type = SOCK_STREAM;
addr_to_string (d[child].sa, d[child].sock_len,
d[child].addr_string, sizeof(d[child].addr_string));
}
/*
* Grow `d' to handle at least `n'.
* Return != 0 if fails
*/
static int
grow_descr (struct descr *d, size_t n)
{
if (d->size - d->len < n) {
unsigned char *tmp;
size_t grow;
grow = max(1024, d->len + n);
if (d->size + grow > max_request) {
kdc_log(0, "Request exceeds max request size (%lu bytes).",
(unsigned long)d->size + grow);
clear_descr(d);
return -1;
}
tmp = realloc (d->buf, d->size + grow);
if (tmp == NULL) {
kdc_log(0, "Failed to re-allocate %lu bytes.",
(unsigned long)d->size + grow);
clear_descr(d);
return -1;
}
d->size += grow;
d->buf = tmp;
}
return 0;
}
/*
* Try to handle the TCP data at `d->buf, d->len'.
* Return -1 if failed, 0 if succesful, and 1 if data is complete.
*/
static int
handle_vanilla_tcp (struct descr *d)
{
krb5_storage *sp;
int32_t len;
sp = krb5_storage_from_mem(d->buf, d->len);
if (sp == NULL) {
kdc_log (0, "krb5_storage_from_mem failed");
return -1;
}
krb5_ret_int32(sp, &len);
krb5_storage_free(sp);
if(d->len - 4 >= len) {
memmove(d->buf, d->buf + 4, d->len - 4);
return 1;
}
return 0;
}
/*
* Try to handle the TCP/HTTP data at `d->buf, d->len'.
* Return -1 if failed, 0 if succesful, and 1 if data is complete.
*/
static int
handle_http_tcp (struct descr *d)
{
char *s, *p, *t;
void *data;
char *proto;
int len;
s = (char *)d->buf;
p = strstr(s, "\r\n");
if (p == NULL) {
kdc_log(0, "Malformed HTTP request from %s", d->addr_string);
return -1;
}
*p = 0;
p = NULL;
t = strtok_r(s, " \t", &p);
if (t == NULL) {
kdc_log(0, "Malformed HTTP request from %s", d->addr_string);
return -1;
}
t = strtok_r(NULL, " \t", &p);
if(t == NULL) {
kdc_log(0, "Malformed HTTP request from %s", d->addr_string);
return -1;
}
data = malloc(strlen(t));
if (data == NULL) {
kdc_log(0, "Failed to allocate %lu bytes",
(unsigned long)strlen(t));
return -1;
}
if(*t == '/')
t++;
if(de_http(t) != 0) {
kdc_log(0, "Malformed HTTP request from %s", d->addr_string);
kdc_log(5, "Request: %s", t);
free(data);
return -1;
}
proto = strtok_r(NULL, " \t", &p);
if (proto == NULL) {
kdc_log(0, "Malformed HTTP request from %s", d->addr_string);
free(data);
return -1;
}
len = base64_decode(t, data);
if(len <= 0){
const char *msg =
" 404 Not found\r\n"
"Server: Heimdal/" VERSION "\r\n"
"Cache-Control: no-cache\r\n"
"Pragma: no-cache\r\n"
"Content-type: text/html\r\n"
"Content-transfer-encoding: 8bit\r\n\r\n"
"<TITLE>404 Not found</TITLE>\r\n"
"<H1>404 Not found</H1>\r\n"
"That page doesn't exist, maybe you are looking for "
"<A HREF=\"http://www.pdc.kth.se/heimdal/\">Heimdal</A>?\r\n";
write(d->s, proto, strlen(proto));
write(d->s, msg, strlen(msg));
kdc_log(0, "HTTP request from %s is non KDC request", d->addr_string);
kdc_log(5, "Request: %s", t);
free(data);
return -1;
}
{
const char *msg =
" 200 OK\r\n"
"Server: Heimdal/" VERSION "\r\n"
"Cache-Control: no-cache\r\n"
"Pragma: no-cache\r\n"
"Content-type: application/octet-stream\r\n"
"Content-transfer-encoding: binary\r\n\r\n";
write(d->s, proto, strlen(proto));
write(d->s, msg, strlen(msg));
}
memcpy(d->buf, data, len);
d->len = len;
free(data);
return 1;
}
/*
* Handle incoming data to the TCP socket in `d[index]'
*/
static void
handle_tcp(struct descr *d, int index, int min_free)
{
unsigned char buf[1024];
int n;
int ret = 0;
if (d[index].timeout == 0) {
add_new_tcp (d, index, min_free);
return;
}
n = recvfrom(d[index].s, buf, sizeof(buf), 0, NULL, NULL);
if(n < 0){
krb5_warn(context, errno, "recvfrom");
return;
} else if (n == 0) {
krb5_warnx(context, "connection closed before end of data after %lu "
"bytes from %s",
(unsigned long)d[index].len, d[index].addr_string);
clear_descr (d + index);
return;
}
if (grow_descr (&d[index], n))
return;
memcpy(d[index].buf + d[index].len, buf, n);
d[index].len += n;
if(d[index].len > 4 && d[index].buf[0] == 0) {
ret = handle_vanilla_tcp (&d[index]);
} else if(enable_http &&
d[index].len >= 4 &&
strncmp((char *)d[index].buf, "GET ", 4) == 0 &&
strncmp((char *)d[index].buf + d[index].len - 4,
"\r\n\r\n", 4) == 0) {
ret = handle_http_tcp (&d[index]);
if (ret < 0)
clear_descr (d + index);
} else if (d[index].len > 4) {
kdc_log (0, "TCP data of strange type from %s", d[index].addr_string);
return;
}
if (ret < 0)
return;
else if (ret == 1) {
do_request(d[index].buf, d[index].len, 1, &d[index]);
clear_descr(d + index);
}
}
void
loop(void)
{
struct descr *d;
int ndescr;
ndescr = init_sockets(&d);
if(ndescr <= 0)
krb5_errx(context, 1, "No sockets!");
while(exit_flag == 0){
struct timeval tmout;
fd_set fds;
int min_free = -1;
int max_fd = 0;
int i;
FD_ZERO(&fds);
for(i = 0; i < ndescr; i++) {
if(d[i].s >= 0){
if(d[i].type == SOCK_STREAM &&
d[i].timeout && d[i].timeout < time(NULL)) {
kdc_log(1, "TCP-connection from %s expired after %lu bytes",
d[i].addr_string, (unsigned long)d[i].len);
clear_descr(&d[i]);
continue;
}
if(max_fd < d[i].s)
max_fd = d[i].s;
if (max_fd >= FD_SETSIZE)
krb5_errx(context, 1, "fd too large");
FD_SET(d[i].s, &fds);
} else if(min_free < 0 || i < min_free)
min_free = i;
}
if(min_free == -1){
struct descr *tmp;
tmp = realloc(d, (ndescr + 4) * sizeof(*d));
if(tmp == NULL)
krb5_warnx(context, "No memory");
else {
d = tmp;
reinit_descrs (d, ndescr);
memset(d + ndescr, 0, 4 * sizeof(*d));
for(i = ndescr; i < ndescr + 4; i++)
init_descr (&d[i]);
min_free = ndescr;
ndescr += 4;
}
}
tmout.tv_sec = TCP_TIMEOUT;
tmout.tv_usec = 0;
switch(select(max_fd + 1, &fds, 0, 0, &tmout)){
case 0:
break;
case -1:
if (errno != EINTR)
krb5_warn(context, errno, "select");
break;
default:
for(i = 0; i < ndescr; i++)
if(d[i].s >= 0 && FD_ISSET(d[i].s, &fds)) {
if(d[i].type == SOCK_DGRAM)
handle_udp(&d[i]);
else if(d[i].type == SOCK_STREAM)
handle_tcp(d, i, min_free);
}
}
}
free (d);
}