aseprite/third_party/curl/lib/krb4.c
2011-06-02 21:03:03 -03:00

432 lines
12 KiB
C

/* This source code was modified by Martin Hedenfalk <mhe@stacken.kth.se> for
* use in Curl. Martin's latest changes were done 2000-09-18.
*
* It has since been patched away like a madman by Daniel Stenberg to make it
* better applied to curl conditions, and to make it not use globals, pollute
* name space and more.
*
* Copyright (c) 1995, 1996, 1997, 1998, 1999 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* Copyright (c) 2004 - 2010 Daniel Stenberg
* 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 "setup.h"
#ifndef CURL_DISABLE_FTP
#ifdef HAVE_KRB4
#include <stdlib.h>
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#include <string.h>
#include <krb.h>
#include <des.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h> /* for getpid() */
#endif
#include "urldata.h"
#include "curl_base64.h"
#include "ftp.h"
#include "sendf.h"
#include "krb4.h"
#include "inet_ntop.h"
#include "curl_memory.h"
/* The last #include file should be: */
#include "memdebug.h"
#define LOCAL_ADDR (&conn->local_addr)
#define REMOTE_ADDR conn->ip_addr->ai_addr
#define myctladdr LOCAL_ADDR
#define hisctladdr REMOTE_ADDR
struct krb4_data {
des_cblock key;
des_key_schedule schedule;
char name[ANAME_SZ];
char instance[INST_SZ];
char realm[REALM_SZ];
};
#ifndef HAVE_STRLCPY
/* if it ever goes non-static, make it Curl_ prefixed! */
static size_t
strlcpy (char *dst, const char *src, size_t dst_sz)
{
size_t n;
char *p;
for (p = dst, n = 0;
n + 1 < dst_sz && *src != '\0';
++p, ++src, ++n)
*p = *src;
*p = '\0';
if(*src == '\0')
return n;
else
return n + strlen (src);
}
#else
size_t strlcpy (char *dst, const char *src, size_t dst_sz);
#endif
static int
krb4_check_prot(void *app_data, int level)
{
app_data = NULL; /* prevent compiler warning */
if(level == PROT_CONFIDENTIAL)
return -1;
return 0;
}
static int
krb4_decode(void *app_data, void *buf, int len, int level,
struct connectdata *conn)
{
MSG_DAT m;
int e;
struct krb4_data *d = app_data;
if(level == PROT_SAFE)
e = krb_rd_safe(buf, len, &d->key,
(struct sockaddr_in *)REMOTE_ADDR,
(struct sockaddr_in *)LOCAL_ADDR, &m);
else
e = krb_rd_priv(buf, len, d->schedule, &d->key,
(struct sockaddr_in *)REMOTE_ADDR,
(struct sockaddr_in *)LOCAL_ADDR, &m);
if(e) {
struct SessionHandle *data = conn->data;
infof(data, "krb4_decode: %s\n", krb_get_err_text(e));
return -1;
}
memmove(buf, m.app_data, m.app_length);
return m.app_length;
}
static int
krb4_overhead(void *app_data, int level, int len)
{
/* no arguments are used, just init them to prevent compiler warnings */
app_data = NULL;
level = 0;
len = 0;
return 31;
}
static int
krb4_encode(void *app_data, const void *from, int length, int level, void **to,
struct connectdata *conn)
{
struct krb4_data *d = app_data;
*to = malloc(length + 31);
if(!*to)
return -1;
if(level == PROT_SAFE)
/* NOTE that the void* cast is safe, krb_mk_safe/priv don't modify the
* input buffer
*/
return krb_mk_safe((void*)from, *to, length, &d->key,
(struct sockaddr_in *)LOCAL_ADDR,
(struct sockaddr_in *)REMOTE_ADDR);
else if(level == PROT_PRIVATE)
return krb_mk_priv((void*)from, *to, length, d->schedule, &d->key,
(struct sockaddr_in *)LOCAL_ADDR,
(struct sockaddr_in *)REMOTE_ADDR);
else
return -1;
}
static int
mk_auth(struct krb4_data *d, KTEXT adat,
const char *service, char *host, int checksum)
{
int ret;
CREDENTIALS cred;
char sname[SNAME_SZ], inst[INST_SZ], realm[REALM_SZ];
strlcpy(sname, service, sizeof(sname));
strlcpy(inst, krb_get_phost(host), sizeof(inst));
strlcpy(realm, krb_realmofhost(host), sizeof(realm));
ret = krb_mk_req(adat, sname, inst, realm, checksum);
if(ret)
return ret;
strlcpy(sname, service, sizeof(sname));
strlcpy(inst, krb_get_phost(host), sizeof(inst));
strlcpy(realm, krb_realmofhost(host), sizeof(realm));
ret = krb_get_cred(sname, inst, realm, &cred);
memmove(&d->key, &cred.session, sizeof(des_cblock));
des_key_sched(&d->key, d->schedule);
memset(&cred, 0, sizeof(cred));
return ret;
}
#ifdef HAVE_KRB_GET_OUR_IP_FOR_REALM
int krb_get_our_ip_for_realm(char *, struct in_addr *);
#endif
static int
krb4_auth(void *app_data, struct connectdata *conn)
{
int ret;
char *p;
unsigned char *ptr;
size_t len;
KTEXT_ST adat;
MSG_DAT msg_data;
int checksum;
u_int32_t cs;
struct krb4_data *d = app_data;
char *host = conn->host.name;
ssize_t nread;
int l = sizeof(conn->local_addr);
struct SessionHandle *data = conn->data;
CURLcode result;
if(getsockname(conn->sock[FIRSTSOCKET],
(struct sockaddr *)LOCAL_ADDR, &l) < 0)
perror("getsockname()");
checksum = getpid();
ret = mk_auth(d, &adat, "ftp", host, checksum);
if(ret == KDC_PR_UNKNOWN)
ret = mk_auth(d, &adat, "rcmd", host, checksum);
if(ret) {
infof(data, "%s\n", krb_get_err_text(ret));
return AUTH_CONTINUE;
}
#ifdef HAVE_KRB_GET_OUR_IP_FOR_REALM
if(krb_get_config_bool("nat_in_use")) {
struct sockaddr_in *localaddr = (struct sockaddr_in *)LOCAL_ADDR;
struct in_addr natAddr;
if(krb_get_our_ip_for_realm(krb_realmofhost(host),
&natAddr) != KSUCCESS
&& krb_get_our_ip_for_realm(NULL, &natAddr) != KSUCCESS)
infof(data, "Can't get address for realm %s\n",
krb_realmofhost(host));
else {
if(natAddr.s_addr != localaddr->sin_addr.s_addr) {
char addr_buf[128];
if(Curl_inet_ntop(AF_INET, natAddr, addr_buf, sizeof(addr_buf)))
infof(data, "Using NAT IP address (%s) for kerberos 4\n", addr_buf);
localaddr->sin_addr = natAddr;
}
}
}
#endif
if(Curl_base64_encode(conn->data, (char *)adat.dat, adat.length, &p) < 1) {
Curl_failf(data, "Out of memory base64-encoding");
return AUTH_CONTINUE;
}
result = Curl_ftpsendf(conn, "ADAT %s", p);
free(p);
if(result)
return -2;
if(Curl_GetFTPResponse(&nread, conn, NULL))
return -1;
if(data->state.buffer[0] != '2'){
Curl_failf(data, "Server didn't accept auth data");
return AUTH_ERROR;
}
p = strstr(data->state.buffer, "ADAT=");
if(!p) {
Curl_failf(data, "Remote host didn't send adat reply");
return AUTH_ERROR;
}
p += 5;
len = Curl_base64_decode(p, &ptr);
if(len > sizeof(adat.dat)-1) {
free(ptr);
len=0;
}
if(!len || !ptr) {
Curl_failf(data, "Failed to decode base64 from server");
return AUTH_ERROR;
}
memcpy((char *)adat.dat, ptr, len);
free(ptr);
adat.length = len;
ret = krb_rd_safe(adat.dat, adat.length, &d->key,
(struct sockaddr_in *)hisctladdr,
(struct sockaddr_in *)myctladdr, &msg_data);
if(ret) {
Curl_failf(data, "Error reading reply from server: %s",
krb_get_err_text(ret));
return AUTH_ERROR;
}
krb_get_int(msg_data.app_data, &cs, 4, 0);
if(cs - checksum != 1) {
Curl_failf(data, "Bad checksum returned from server");
return AUTH_ERROR;
}
return AUTH_OK;
}
struct Curl_sec_client_mech Curl_krb4_client_mech = {
"KERBEROS_V4",
sizeof(struct krb4_data),
NULL, /* init */
krb4_auth,
NULL, /* end */
krb4_check_prot,
krb4_overhead,
krb4_encode,
krb4_decode
};
static enum protection_level
krb4_set_command_prot(struct connectdata *conn, enum protection_level level)
{
enum protection_level old = conn->command_prot;
DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
conn->command_prot = level;
return old;
}
CURLcode Curl_krb_kauth(struct connectdata *conn)
{
des_cblock key;
des_key_schedule schedule;
KTEXT_ST tkt, tktcopy;
char *name;
char *p;
char passwd[100];
size_t tmp;
ssize_t nread;
enum protection_level save;
CURLcode result;
unsigned char *ptr;
save = krb4_set_command_prot(conn, PROT_PRIVATE);
result = Curl_ftpsendf(conn, "SITE KAUTH %s", conn->user);
if(result)
return result;
result = Curl_GetFTPResponse(&nread, conn, NULL);
if(result)
return result;
if(conn->data->state.buffer[0] != '3'){
krb4_set_command_prot(conn, save);
return CURLE_FTP_WEIRD_SERVER_REPLY;
}
p = strstr(conn->data->state.buffer, "T=");
if(!p) {
Curl_failf(conn->data, "Bad reply from server");
krb4_set_command_prot(conn, save);
return CURLE_FTP_WEIRD_SERVER_REPLY;
}
p += 2;
tmp = Curl_base64_decode(p, &ptr);
if(tmp >= sizeof(tkt.dat)) {
free(ptr);
tmp=0;
}
if(!tmp || !ptr) {
Curl_failf(conn->data, "Failed to decode base64 in reply");
krb4_set_command_prot(conn, save);
return CURLE_FTP_WEIRD_SERVER_REPLY;
}
memcpy((char *)tkt.dat, ptr, tmp);
free(ptr);
tkt.length = tmp;
tktcopy.length = tkt.length;
p = strstr(conn->data->state.buffer, "P=");
if(!p) {
Curl_failf(conn->data, "Bad reply from server");
krb4_set_command_prot(conn, save);
return CURLE_FTP_WEIRD_SERVER_REPLY;
}
name = p + 2;
for(; *p && *p != ' ' && *p != '\r' && *p != '\n'; p++);
*p = 0;
des_string_to_key (conn->passwd, &key);
des_key_sched(&key, schedule);
des_pcbc_encrypt((void *)tkt.dat, (void *)tktcopy.dat,
tkt.length,
schedule, &key, DES_DECRYPT);
if(strcmp ((char*)tktcopy.dat + 8,
KRB_TICKET_GRANTING_TICKET) != 0) {
afs_string_to_key(passwd,
krb_realmofhost(conn->host.name),
&key);
des_key_sched(&key, schedule);
des_pcbc_encrypt((void *)tkt.dat, (void *)tktcopy.dat,
tkt.length,
schedule, &key, DES_DECRYPT);
}
memset(key, 0, sizeof(key));
memset(schedule, 0, sizeof(schedule));
memset(passwd, 0, sizeof(passwd));
if(Curl_base64_encode(conn->data, (char *)tktcopy.dat, tktcopy.length, &p)
< 1) {
failf(conn->data, "Out of memory base64-encoding.");
krb4_set_command_prot(conn, save);
return CURLE_OUT_OF_MEMORY;
}
memset (tktcopy.dat, 0, tktcopy.length);
result = Curl_ftpsendf(conn, "SITE KAUTH %s %s", name, p);
free(p);
if(result)
return result;
result = Curl_GetFTPResponse(&nread, conn, NULL);
if(result)
return result;
krb4_set_command_prot(conn, save);
return CURLE_OK;
}
#endif /* HAVE_KRB4 */
#endif /* CURL_DISABLE_FTP */