| Current Path : /usr/src/lib/libradius/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/lib/libradius/radlib.c |
/*-
* Copyright 1998 Juniper Networks, Inc.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/lib/libradius/radlib.c 234191 2012-04-12 17:49:53Z melifaro $");
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#ifdef WITH_SSL
#include <openssl/hmac.h>
#include <openssl/md5.h>
#define MD5Init MD5_Init
#define MD5Update MD5_Update
#define MD5Final MD5_Final
#else
#define MD5_DIGEST_LENGTH 16
#include <md5.h>
#endif
/* We need the MPPE_KEY_LEN define */
#include <netgraph/ng_mppc.h>
#include <errno.h>
#include <netdb.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "radlib_private.h"
static void clear_password(struct rad_handle *);
static void generr(struct rad_handle *, const char *, ...)
__printflike(2, 3);
static void insert_scrambled_password(struct rad_handle *, int);
static void insert_request_authenticator(struct rad_handle *, int);
static void insert_message_authenticator(struct rad_handle *, int);
static int is_valid_response(struct rad_handle *, int,
const struct sockaddr_in *);
static int put_password_attr(struct rad_handle *, int,
const void *, size_t);
static int put_raw_attr(struct rad_handle *, int,
const void *, size_t);
static int split(char *, char *[], int, char *, size_t);
static void
clear_password(struct rad_handle *h)
{
if (h->pass_len != 0) {
memset(h->pass, 0, h->pass_len);
h->pass_len = 0;
}
h->pass_pos = 0;
}
static void
generr(struct rad_handle *h, const char *format, ...)
{
va_list ap;
va_start(ap, format);
vsnprintf(h->errmsg, ERRSIZE, format, ap);
va_end(ap);
}
static void
insert_scrambled_password(struct rad_handle *h, int srv)
{
MD5_CTX ctx;
unsigned char md5[MD5_DIGEST_LENGTH];
const struct rad_server *srvp;
int padded_len;
int pos;
srvp = &h->servers[srv];
padded_len = h->pass_len == 0 ? 16 : (h->pass_len+15) & ~0xf;
memcpy(md5, &h->out[POS_AUTH], LEN_AUTH);
for (pos = 0; pos < padded_len; pos += 16) {
int i;
/* Calculate the new scrambler */
MD5Init(&ctx);
MD5Update(&ctx, srvp->secret, strlen(srvp->secret));
MD5Update(&ctx, md5, 16);
MD5Final(md5, &ctx);
/*
* Mix in the current chunk of the password, and copy
* the result into the right place in the request. Also
* modify the scrambler in place, since we will use this
* in calculating the scrambler for next time.
*/
for (i = 0; i < 16; i++)
h->out[h->pass_pos + pos + i] =
md5[i] ^= h->pass[pos + i];
}
}
static void
insert_request_authenticator(struct rad_handle *h, int resp)
{
MD5_CTX ctx;
const struct rad_server *srvp;
srvp = &h->servers[h->srv];
/* Create the request authenticator */
MD5Init(&ctx);
MD5Update(&ctx, &h->out[POS_CODE], POS_AUTH - POS_CODE);
if (resp)
MD5Update(&ctx, &h->in[POS_AUTH], LEN_AUTH);
else
MD5Update(&ctx, &h->out[POS_AUTH], LEN_AUTH);
MD5Update(&ctx, &h->out[POS_ATTRS], h->out_len - POS_ATTRS);
MD5Update(&ctx, srvp->secret, strlen(srvp->secret));
MD5Final(&h->out[POS_AUTH], &ctx);
}
static void
insert_message_authenticator(struct rad_handle *h, int resp)
{
#ifdef WITH_SSL
u_char md[EVP_MAX_MD_SIZE];
u_int md_len;
const struct rad_server *srvp;
HMAC_CTX ctx;
srvp = &h->servers[h->srv];
if (h->authentic_pos != 0) {
HMAC_CTX_init(&ctx);
HMAC_Init(&ctx, srvp->secret, strlen(srvp->secret), EVP_md5());
HMAC_Update(&ctx, &h->out[POS_CODE], POS_AUTH - POS_CODE);
if (resp)
HMAC_Update(&ctx, &h->in[POS_AUTH], LEN_AUTH);
else
HMAC_Update(&ctx, &h->out[POS_AUTH], LEN_AUTH);
HMAC_Update(&ctx, &h->out[POS_ATTRS],
h->out_len - POS_ATTRS);
HMAC_Final(&ctx, md, &md_len);
HMAC_CTX_cleanup(&ctx);
HMAC_cleanup(&ctx);
memcpy(&h->out[h->authentic_pos + 2], md, md_len);
}
#endif
}
/*
* Return true if the current response is valid for a request to the
* specified server.
*/
static int
is_valid_response(struct rad_handle *h, int srv,
const struct sockaddr_in *from)
{
MD5_CTX ctx;
unsigned char md5[MD5_DIGEST_LENGTH];
const struct rad_server *srvp;
int len;
#ifdef WITH_SSL
HMAC_CTX hctx;
u_char resp[MSGSIZE], md[EVP_MAX_MD_SIZE];
u_int md_len;
int pos;
#endif
srvp = &h->servers[srv];
/* Check the source address */
if (from->sin_family != srvp->addr.sin_family ||
from->sin_addr.s_addr != srvp->addr.sin_addr.s_addr ||
from->sin_port != srvp->addr.sin_port)
return 0;
/* Check the message length */
if (h->in_len < POS_ATTRS)
return 0;
len = h->in[POS_LENGTH] << 8 | h->in[POS_LENGTH+1];
if (len > h->in_len)
return 0;
/* Check the response authenticator */
MD5Init(&ctx);
MD5Update(&ctx, &h->in[POS_CODE], POS_AUTH - POS_CODE);
MD5Update(&ctx, &h->out[POS_AUTH], LEN_AUTH);
MD5Update(&ctx, &h->in[POS_ATTRS], len - POS_ATTRS);
MD5Update(&ctx, srvp->secret, strlen(srvp->secret));
MD5Final(md5, &ctx);
if (memcmp(&h->in[POS_AUTH], md5, sizeof md5) != 0)
return 0;
#ifdef WITH_SSL
/*
* For non accounting responses check the message authenticator,
* if any.
*/
if (h->in[POS_CODE] != RAD_ACCOUNTING_RESPONSE) {
memcpy(resp, h->in, MSGSIZE);
pos = POS_ATTRS;
/* Search and verify the Message-Authenticator */
while (pos < len - 2) {
if (h->in[pos] == RAD_MESSAGE_AUTHENTIC) {
/* zero fill the Message-Authenticator */
memset(&resp[pos + 2], 0, MD5_DIGEST_LENGTH);
HMAC_CTX_init(&hctx);
HMAC_Init(&hctx, srvp->secret,
strlen(srvp->secret), EVP_md5());
HMAC_Update(&hctx, &h->in[POS_CODE],
POS_AUTH - POS_CODE);
HMAC_Update(&hctx, &h->out[POS_AUTH],
LEN_AUTH);
HMAC_Update(&hctx, &resp[POS_ATTRS],
h->in_len - POS_ATTRS);
HMAC_Final(&hctx, md, &md_len);
HMAC_CTX_cleanup(&hctx);
HMAC_cleanup(&hctx);
if (memcmp(md, &h->in[pos + 2],
MD5_DIGEST_LENGTH) != 0)
return 0;
break;
}
pos += h->in[pos + 1];
}
}
#endif
return 1;
}
/*
* Return true if the current request is valid for the specified server.
*/
static int
is_valid_request(struct rad_handle *h)
{
MD5_CTX ctx;
unsigned char md5[MD5_DIGEST_LENGTH];
const struct rad_server *srvp;
int len;
#ifdef WITH_SSL
HMAC_CTX hctx;
u_char resp[MSGSIZE], md[EVP_MAX_MD_SIZE];
u_int md_len;
int pos;
#endif
srvp = &h->servers[h->srv];
/* Check the message length */
if (h->in_len < POS_ATTRS)
return (0);
len = h->in[POS_LENGTH] << 8 | h->in[POS_LENGTH+1];
if (len > h->in_len)
return (0);
if (h->in[POS_CODE] != RAD_ACCESS_REQUEST) {
uint32_t zeroes[4] = { 0, 0, 0, 0 };
/* Check the request authenticator */
MD5Init(&ctx);
MD5Update(&ctx, &h->in[POS_CODE], POS_AUTH - POS_CODE);
MD5Update(&ctx, zeroes, LEN_AUTH);
MD5Update(&ctx, &h->in[POS_ATTRS], len - POS_ATTRS);
MD5Update(&ctx, srvp->secret, strlen(srvp->secret));
MD5Final(md5, &ctx);
if (memcmp(&h->in[POS_AUTH], md5, sizeof md5) != 0)
return (0);
}
#ifdef WITH_SSL
/* Search and verify the Message-Authenticator */
pos = POS_ATTRS;
while (pos < len - 2) {
if (h->in[pos] == RAD_MESSAGE_AUTHENTIC) {
memcpy(resp, h->in, MSGSIZE);
/* zero fill the Request-Authenticator */
if (h->in[POS_CODE] != RAD_ACCESS_REQUEST)
memset(&resp[POS_AUTH], 0, LEN_AUTH);
/* zero fill the Message-Authenticator */
memset(&resp[pos + 2], 0, MD5_DIGEST_LENGTH);
HMAC_CTX_init(&hctx);
HMAC_Init(&hctx, srvp->secret,
strlen(srvp->secret), EVP_md5());
HMAC_Update(&hctx, resp, h->in_len);
HMAC_Final(&hctx, md, &md_len);
HMAC_CTX_cleanup(&hctx);
HMAC_cleanup(&hctx);
if (memcmp(md, &h->in[pos + 2],
MD5_DIGEST_LENGTH) != 0)
return (0);
break;
}
pos += h->in[pos + 1];
}
#endif
return (1);
}
static int
put_password_attr(struct rad_handle *h, int type, const void *value, size_t len)
{
int padded_len;
int pad_len;
if (h->pass_pos != 0) {
generr(h, "Multiple User-Password attributes specified");
return -1;
}
if (len > PASSSIZE)
len = PASSSIZE;
padded_len = len == 0 ? 16 : (len+15) & ~0xf;
pad_len = padded_len - len;
/*
* Put in a place-holder attribute containing all zeros, and
* remember where it is so we can fill it in later.
*/
clear_password(h);
put_raw_attr(h, type, h->pass, padded_len);
h->pass_pos = h->out_len - padded_len;
/* Save the cleartext password, padded as necessary */
memcpy(h->pass, value, len);
h->pass_len = len;
memset(h->pass + len, 0, pad_len);
return 0;
}
static int
put_raw_attr(struct rad_handle *h, int type, const void *value, size_t len)
{
if (len > 253) {
generr(h, "Attribute too long");
return -1;
}
if (h->out_len + 2 + len > MSGSIZE) {
generr(h, "Maximum message length exceeded");
return -1;
}
h->out[h->out_len++] = type;
h->out[h->out_len++] = len + 2;
memcpy(&h->out[h->out_len], value, len);
h->out_len += len;
return 0;
}
int
rad_add_server(struct rad_handle *h, const char *host, int port,
const char *secret, int timeout, int tries)
{
struct rad_server *srvp;
if (h->num_servers >= MAXSERVERS) {
generr(h, "Too many RADIUS servers specified");
return -1;
}
srvp = &h->servers[h->num_servers];
memset(&srvp->addr, 0, sizeof srvp->addr);
srvp->addr.sin_len = sizeof srvp->addr;
srvp->addr.sin_family = AF_INET;
if (!inet_aton(host, &srvp->addr.sin_addr)) {
struct hostent *hent;
if ((hent = gethostbyname(host)) == NULL) {
generr(h, "%s: host not found", host);
return -1;
}
memcpy(&srvp->addr.sin_addr, hent->h_addr,
sizeof srvp->addr.sin_addr);
}
if (port != 0)
srvp->addr.sin_port = htons((u_short)port);
else {
struct servent *sent;
if (h->type == RADIUS_AUTH)
srvp->addr.sin_port =
(sent = getservbyname("radius", "udp")) != NULL ?
sent->s_port : htons(RADIUS_PORT);
else
srvp->addr.sin_port =
(sent = getservbyname("radacct", "udp")) != NULL ?
sent->s_port : htons(RADACCT_PORT);
}
if ((srvp->secret = strdup(secret)) == NULL) {
generr(h, "Out of memory");
return -1;
}
srvp->timeout = timeout;
srvp->max_tries = tries;
srvp->num_tries = 0;
h->num_servers++;
return 0;
}
void
rad_close(struct rad_handle *h)
{
int srv;
if (h->fd != -1)
close(h->fd);
for (srv = 0; srv < h->num_servers; srv++) {
memset(h->servers[srv].secret, 0,
strlen(h->servers[srv].secret));
free(h->servers[srv].secret);
}
clear_password(h);
free(h);
}
int
rad_config(struct rad_handle *h, const char *path)
{
FILE *fp;
char buf[MAXCONFLINE];
int linenum;
int retval;
if (path == NULL)
path = PATH_RADIUS_CONF;
if ((fp = fopen(path, "r")) == NULL) {
generr(h, "Cannot open \"%s\": %s", path, strerror(errno));
return -1;
}
retval = 0;
linenum = 0;
while (fgets(buf, sizeof buf, fp) != NULL) {
int len;
char *fields[5];
int nfields;
char msg[ERRSIZE];
char *type;
char *host, *res;
char *port_str;
char *secret;
char *timeout_str;
char *maxtries_str;
char *end;
char *wanttype;
unsigned long timeout;
unsigned long maxtries;
int port;
int i;
linenum++;
len = strlen(buf);
/* We know len > 0, else fgets would have returned NULL. */
if (buf[len - 1] != '\n') {
if (len == sizeof buf - 1)
generr(h, "%s:%d: line too long", path,
linenum);
else
generr(h, "%s:%d: missing newline", path,
linenum);
retval = -1;
break;
}
buf[len - 1] = '\0';
/* Extract the fields from the line. */
nfields = split(buf, fields, 5, msg, sizeof msg);
if (nfields == -1) {
generr(h, "%s:%d: %s", path, linenum, msg);
retval = -1;
break;
}
if (nfields == 0)
continue;
/*
* The first field should contain "auth" or "acct" for
* authentication or accounting, respectively. But older
* versions of the file didn't have that field. Default
* it to "auth" for backward compatibility.
*/
if (strcmp(fields[0], "auth") != 0 &&
strcmp(fields[0], "acct") != 0) {
if (nfields >= 5) {
generr(h, "%s:%d: invalid service type", path,
linenum);
retval = -1;
break;
}
nfields++;
for (i = nfields; --i > 0; )
fields[i] = fields[i - 1];
fields[0] = "auth";
}
if (nfields < 3) {
generr(h, "%s:%d: missing shared secret", path,
linenum);
retval = -1;
break;
}
type = fields[0];
host = fields[1];
secret = fields[2];
timeout_str = fields[3];
maxtries_str = fields[4];
/* Ignore the line if it is for the wrong service type. */
wanttype = h->type == RADIUS_AUTH ? "auth" : "acct";
if (strcmp(type, wanttype) != 0)
continue;
/* Parse and validate the fields. */
res = host;
host = strsep(&res, ":");
port_str = strsep(&res, ":");
if (port_str != NULL) {
port = strtoul(port_str, &end, 10);
if (*end != '\0') {
generr(h, "%s:%d: invalid port", path,
linenum);
retval = -1;
break;
}
} else
port = 0;
if (timeout_str != NULL) {
timeout = strtoul(timeout_str, &end, 10);
if (*end != '\0') {
generr(h, "%s:%d: invalid timeout", path,
linenum);
retval = -1;
break;
}
} else
timeout = TIMEOUT;
if (maxtries_str != NULL) {
maxtries = strtoul(maxtries_str, &end, 10);
if (*end != '\0') {
generr(h, "%s:%d: invalid maxtries", path,
linenum);
retval = -1;
break;
}
} else
maxtries = MAXTRIES;
if (rad_add_server(h, host, port, secret, timeout, maxtries) ==
-1) {
strcpy(msg, h->errmsg);
generr(h, "%s:%d: %s", path, linenum, msg);
retval = -1;
break;
}
}
/* Clear out the buffer to wipe a possible copy of a shared secret */
memset(buf, 0, sizeof buf);
fclose(fp);
return retval;
}
/*
* rad_init_send_request() must have previously been called.
* Returns:
* 0 The application should select on *fd with a timeout of tv before
* calling rad_continue_send_request again.
* < 0 Failure
* > 0 Success
*/
int
rad_continue_send_request(struct rad_handle *h, int selected, int *fd,
struct timeval *tv)
{
int n;
if (h->type == RADIUS_SERVER) {
generr(h, "denied function call");
return (-1);
}
if (selected) {
struct sockaddr_in from;
socklen_t fromlen;
fromlen = sizeof from;
h->in_len = recvfrom(h->fd, h->in,
MSGSIZE, MSG_WAITALL, (struct sockaddr *)&from, &fromlen);
if (h->in_len == -1) {
generr(h, "recvfrom: %s", strerror(errno));
return -1;
}
if (is_valid_response(h, h->srv, &from)) {
h->in_len = h->in[POS_LENGTH] << 8 |
h->in[POS_LENGTH+1];
h->in_pos = POS_ATTRS;
return h->in[POS_CODE];
}
}
if (h->try == h->total_tries) {
generr(h, "No valid RADIUS responses received");
return -1;
}
/*
* Scan round-robin to the next server that has some
* tries left. There is guaranteed to be one, or we
* would have exited this loop by now.
*/
while (h->servers[h->srv].num_tries >= h->servers[h->srv].max_tries)
if (++h->srv >= h->num_servers)
h->srv = 0;
if (h->out[POS_CODE] == RAD_ACCESS_REQUEST) {
/* Insert the scrambled password into the request */
if (h->pass_pos != 0)
insert_scrambled_password(h, h->srv);
}
insert_message_authenticator(h, 0);
if (h->out[POS_CODE] != RAD_ACCESS_REQUEST) {
/* Insert the request authenticator into the request */
insert_request_authenticator(h, h->srv);
}
/* Send the request */
n = sendto(h->fd, h->out, h->out_len, 0,
(const struct sockaddr *)&h->servers[h->srv].addr,
sizeof h->servers[h->srv].addr);
if (n != h->out_len)
tv->tv_sec = 1; /* Do not wait full timeout if send failed. */
else
tv->tv_sec = h->servers[h->srv].timeout;
h->try++;
h->servers[h->srv].num_tries++;
tv->tv_usec = 0;
*fd = h->fd;
return 0;
}
int
rad_receive_request(struct rad_handle *h)
{
struct sockaddr_in from;
socklen_t fromlen;
int n;
if (h->type != RADIUS_SERVER) {
generr(h, "denied function call");
return (-1);
}
h->srv = -1;
fromlen = sizeof(from);
h->in_len = recvfrom(h->fd, h->in,
MSGSIZE, MSG_WAITALL, (struct sockaddr *)&from, &fromlen);
if (h->in_len == -1) {
generr(h, "recvfrom: %s", strerror(errno));
return (-1);
}
for (n = 0; n < h->num_servers; n++) {
if (h->servers[n].addr.sin_addr.s_addr == from.sin_addr.s_addr) {
h->servers[n].addr.sin_port = from.sin_port;
h->srv = n;
break;
}
}
if (h->srv == -1)
return (-2);
if (is_valid_request(h)) {
h->in_len = h->in[POS_LENGTH] << 8 |
h->in[POS_LENGTH+1];
h->in_pos = POS_ATTRS;
return (h->in[POS_CODE]);
}
return (-3);
}
int
rad_send_response(struct rad_handle *h)
{
int n;
if (h->type != RADIUS_SERVER) {
generr(h, "denied function call");
return (-1);
}
/* Fill in the length field in the message */
h->out[POS_LENGTH] = h->out_len >> 8;
h->out[POS_LENGTH+1] = h->out_len;
insert_message_authenticator(h,
(h->in[POS_CODE] == RAD_ACCESS_REQUEST) ? 1 : 0);
insert_request_authenticator(h, 1);
/* Send the request */
n = sendto(h->fd, h->out, h->out_len, 0,
(const struct sockaddr *)&h->servers[h->srv].addr,
sizeof h->servers[h->srv].addr);
if (n != h->out_len) {
if (n == -1)
generr(h, "sendto: %s", strerror(errno));
else
generr(h, "sendto: short write");
return -1;
}
return 0;
}
int
rad_create_request(struct rad_handle *h, int code)
{
int i;
if (h->type == RADIUS_SERVER) {
generr(h, "denied function call");
return (-1);
}
h->out[POS_CODE] = code;
h->out[POS_IDENT] = ++h->ident;
if (code == RAD_ACCESS_REQUEST) {
/* Create a random authenticator */
for (i = 0; i < LEN_AUTH; i += 2) {
long r;
r = random();
h->out[POS_AUTH+i] = (u_char)r;
h->out[POS_AUTH+i+1] = (u_char)(r >> 8);
}
} else
memset(&h->out[POS_AUTH], 0, LEN_AUTH);
h->out_len = POS_ATTRS;
clear_password(h);
h->authentic_pos = 0;
h->out_created = 1;
h->bindto = INADDR_ANY;
return 0;
}
void
rad_bind_to(struct rad_handle *h, in_addr_t addr)
{
h->bindto = addr;
}
int
rad_create_response(struct rad_handle *h, int code)
{
if (h->type != RADIUS_SERVER) {
generr(h, "denied function call");
return (-1);
}
h->out[POS_CODE] = code;
h->out[POS_IDENT] = h->in[POS_IDENT];
memset(&h->out[POS_AUTH], 0, LEN_AUTH);
h->out_len = POS_ATTRS;
clear_password(h);
h->authentic_pos = 0;
h->out_created = 1;
return 0;
}
struct in_addr
rad_cvt_addr(const void *data)
{
struct in_addr value;
memcpy(&value.s_addr, data, sizeof value.s_addr);
return value;
}
u_int32_t
rad_cvt_int(const void *data)
{
u_int32_t value;
memcpy(&value, data, sizeof value);
return ntohl(value);
}
char *
rad_cvt_string(const void *data, size_t len)
{
char *s;
s = malloc(len + 1);
if (s != NULL) {
memcpy(s, data, len);
s[len] = '\0';
}
return s;
}
/*
* Returns the attribute type. If none are left, returns 0. On failure,
* returns -1.
*/
int
rad_get_attr(struct rad_handle *h, const void **value, size_t *len)
{
int type;
if (h->in_pos >= h->in_len)
return 0;
if (h->in_pos + 2 > h->in_len) {
generr(h, "Malformed attribute in response");
return -1;
}
type = h->in[h->in_pos++];
*len = h->in[h->in_pos++] - 2;
if (h->in_pos + (int)*len > h->in_len) {
generr(h, "Malformed attribute in response");
return -1;
}
*value = &h->in[h->in_pos];
h->in_pos += *len;
return type;
}
/*
* Returns -1 on error, 0 to indicate no event and >0 for success
*/
int
rad_init_send_request(struct rad_handle *h, int *fd, struct timeval *tv)
{
int srv;
if (h->type == RADIUS_SERVER) {
generr(h, "denied function call");
return (-1);
}
/* Make sure we have a socket to use */
if (h->fd == -1) {
struct sockaddr_in sin;
if ((h->fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) {
generr(h, "Cannot create socket: %s", strerror(errno));
return -1;
}
memset(&sin, 0, sizeof sin);
sin.sin_len = sizeof sin;
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = h->bindto;
sin.sin_port = htons(0);
if (bind(h->fd, (const struct sockaddr *)&sin,
sizeof sin) == -1) {
generr(h, "bind: %s", strerror(errno));
close(h->fd);
h->fd = -1;
return -1;
}
}
if (h->out[POS_CODE] != RAD_ACCESS_REQUEST) {
/* Make sure no password given */
if (h->pass_pos || h->chap_pass) {
generr(h, "User or Chap Password"
" in accounting request");
return -1;
}
} else {
if (h->eap_msg == 0) {
/* Make sure the user gave us a password */
if (h->pass_pos == 0 && !h->chap_pass) {
generr(h, "No User or Chap Password"
" attributes given");
return -1;
}
if (h->pass_pos != 0 && h->chap_pass) {
generr(h, "Both User and Chap Password"
" attributes given");
return -1;
}
}
}
/* Fill in the length field in the message */
h->out[POS_LENGTH] = h->out_len >> 8;
h->out[POS_LENGTH+1] = h->out_len;
/*
* Count the total number of tries we will make, and zero the
* counter for each server.
*/
h->total_tries = 0;
for (srv = 0; srv < h->num_servers; srv++) {
h->total_tries += h->servers[srv].max_tries;
h->servers[srv].num_tries = 0;
}
if (h->total_tries == 0) {
generr(h, "No RADIUS servers specified");
return -1;
}
h->try = h->srv = 0;
return rad_continue_send_request(h, 0, fd, tv);
}
/*
* Create and initialize a rad_handle structure, and return it to the
* caller. Can fail only if the necessary memory cannot be allocated.
* In that case, it returns NULL.
*/
struct rad_handle *
rad_auth_open(void)
{
struct rad_handle *h;
h = (struct rad_handle *)malloc(sizeof(struct rad_handle));
if (h != NULL) {
srandomdev();
h->fd = -1;
h->num_servers = 0;
h->ident = random();
h->errmsg[0] = '\0';
memset(h->pass, 0, sizeof h->pass);
h->pass_len = 0;
h->pass_pos = 0;
h->chap_pass = 0;
h->authentic_pos = 0;
h->type = RADIUS_AUTH;
h->out_created = 0;
h->eap_msg = 0;
}
return h;
}
struct rad_handle *
rad_acct_open(void)
{
struct rad_handle *h;
h = rad_open();
if (h != NULL)
h->type = RADIUS_ACCT;
return h;
}
struct rad_handle *
rad_server_open(int fd)
{
struct rad_handle *h;
h = rad_open();
if (h != NULL) {
h->type = RADIUS_SERVER;
h->fd = fd;
}
return h;
}
struct rad_handle *
rad_open(void)
{
return rad_auth_open();
}
int
rad_put_addr(struct rad_handle *h, int type, struct in_addr addr)
{
return rad_put_attr(h, type, &addr.s_addr, sizeof addr.s_addr);
}
int
rad_put_attr(struct rad_handle *h, int type, const void *value, size_t len)
{
int result;
if (!h->out_created) {
generr(h, "Please call rad_create_request()"
" before putting attributes");
return -1;
}
if (h->out[POS_CODE] == RAD_ACCOUNTING_REQUEST) {
if (type == RAD_EAP_MESSAGE) {
generr(h, "EAP-Message attribute is not valid"
" in accounting requests");
return -1;
}
}
/*
* When proxying EAP Messages, the Message Authenticator
* MUST be present; see RFC 3579.
*/
if (type == RAD_EAP_MESSAGE) {
if (rad_put_message_authentic(h) == -1)
return -1;
}
if (type == RAD_USER_PASSWORD) {
result = put_password_attr(h, type, value, len);
} else if (type == RAD_MESSAGE_AUTHENTIC) {
result = rad_put_message_authentic(h);
} else {
result = put_raw_attr(h, type, value, len);
if (result == 0) {
if (type == RAD_CHAP_PASSWORD)
h->chap_pass = 1;
else if (type == RAD_EAP_MESSAGE)
h->eap_msg = 1;
}
}
return result;
}
int
rad_put_int(struct rad_handle *h, int type, u_int32_t value)
{
u_int32_t nvalue;
nvalue = htonl(value);
return rad_put_attr(h, type, &nvalue, sizeof nvalue);
}
int
rad_put_string(struct rad_handle *h, int type, const char *str)
{
return rad_put_attr(h, type, str, strlen(str));
}
int
rad_put_message_authentic(struct rad_handle *h)
{
#ifdef WITH_SSL
u_char md_zero[MD5_DIGEST_LENGTH];
if (h->out[POS_CODE] == RAD_ACCOUNTING_REQUEST) {
generr(h, "Message-Authenticator is not valid"
" in accounting requests");
return -1;
}
if (h->authentic_pos == 0) {
h->authentic_pos = h->out_len;
memset(md_zero, 0, sizeof(md_zero));
return (put_raw_attr(h, RAD_MESSAGE_AUTHENTIC, md_zero,
sizeof(md_zero)));
}
return 0;
#else
generr(h, "Message Authenticator not supported,"
" please recompile libradius with SSL support");
return -1;
#endif
}
/*
* Returns the response type code on success, or -1 on failure.
*/
int
rad_send_request(struct rad_handle *h)
{
struct timeval timelimit;
struct timeval tv;
int fd;
int n;
n = rad_init_send_request(h, &fd, &tv);
if (n != 0)
return n;
gettimeofday(&timelimit, NULL);
timeradd(&tv, &timelimit, &timelimit);
for ( ; ; ) {
fd_set readfds;
FD_ZERO(&readfds);
FD_SET(fd, &readfds);
n = select(fd + 1, &readfds, NULL, NULL, &tv);
if (n == -1) {
generr(h, "select: %s", strerror(errno));
return -1;
}
if (!FD_ISSET(fd, &readfds)) {
/* Compute a new timeout */
gettimeofday(&tv, NULL);
timersub(&timelimit, &tv, &tv);
if (tv.tv_sec > 0 || (tv.tv_sec == 0 && tv.tv_usec > 0))
/* Continue the select */
continue;
}
n = rad_continue_send_request(h, n, &fd, &tv);
if (n != 0)
return n;
gettimeofday(&timelimit, NULL);
timeradd(&tv, &timelimit, &timelimit);
}
}
const char *
rad_strerror(struct rad_handle *h)
{
return h->errmsg;
}
/*
* Destructively split a string into fields separated by white space.
* `#' at the beginning of a field begins a comment that extends to the
* end of the string. Fields may be quoted with `"'. Inside quoted
* strings, the backslash escapes `\"' and `\\' are honored.
*
* Pointers to up to the first maxfields fields are stored in the fields
* array. Missing fields get NULL pointers.
*
* The return value is the actual number of fields parsed, and is always
* <= maxfields.
*
* On a syntax error, places a message in the msg string, and returns -1.
*/
static int
split(char *str, char *fields[], int maxfields, char *msg, size_t msglen)
{
char *p;
int i;
static const char ws[] = " \t";
for (i = 0; i < maxfields; i++)
fields[i] = NULL;
p = str;
i = 0;
while (*p != '\0') {
p += strspn(p, ws);
if (*p == '#' || *p == '\0')
break;
if (i >= maxfields) {
snprintf(msg, msglen, "line has too many fields");
return -1;
}
if (*p == '"') {
char *dst;
dst = ++p;
fields[i] = dst;
while (*p != '"') {
if (*p == '\\') {
p++;
if (*p != '"' && *p != '\\' &&
*p != '\0') {
snprintf(msg, msglen,
"invalid `\\' escape");
return -1;
}
}
if (*p == '\0') {
snprintf(msg, msglen,
"unterminated quoted string");
return -1;
}
*dst++ = *p++;
}
*dst = '\0';
p++;
if (*fields[i] == '\0') {
snprintf(msg, msglen,
"empty quoted string not permitted");
return -1;
}
if (*p != '\0' && strspn(p, ws) == 0) {
snprintf(msg, msglen, "quoted string not"
" followed by white space");
return -1;
}
} else {
fields[i] = p;
p += strcspn(p, ws);
if (*p != '\0')
*p++ = '\0';
}
i++;
}
return i;
}
int
rad_get_vendor_attr(u_int32_t *vendor, const void **data, size_t *len)
{
struct vendor_attribute *attr;
attr = (struct vendor_attribute *)*data;
*vendor = ntohl(attr->vendor_value);
*data = attr->attrib_data;
*len = attr->attrib_len - 2;
return (attr->attrib_type);
}
int
rad_put_vendor_addr(struct rad_handle *h, int vendor, int type,
struct in_addr addr)
{
return (rad_put_vendor_attr(h, vendor, type, &addr.s_addr,
sizeof addr.s_addr));
}
int
rad_put_vendor_attr(struct rad_handle *h, int vendor, int type,
const void *value, size_t len)
{
struct vendor_attribute *attr;
int res;
if (!h->out_created) {
generr(h, "Please call rad_create_request()"
" before putting attributes");
return -1;
}
if ((attr = malloc(len + 6)) == NULL) {
generr(h, "malloc failure (%zu bytes)", len + 6);
return -1;
}
attr->vendor_value = htonl(vendor);
attr->attrib_type = type;
attr->attrib_len = len + 2;
memcpy(attr->attrib_data, value, len);
res = put_raw_attr(h, RAD_VENDOR_SPECIFIC, attr, len + 6);
free(attr);
if (res == 0 && vendor == RAD_VENDOR_MICROSOFT
&& (type == RAD_MICROSOFT_MS_CHAP_RESPONSE
|| type == RAD_MICROSOFT_MS_CHAP2_RESPONSE)) {
h->chap_pass = 1;
}
return (res);
}
int
rad_put_vendor_int(struct rad_handle *h, int vendor, int type, u_int32_t i)
{
u_int32_t value;
value = htonl(i);
return (rad_put_vendor_attr(h, vendor, type, &value, sizeof value));
}
int
rad_put_vendor_string(struct rad_handle *h, int vendor, int type,
const char *str)
{
return (rad_put_vendor_attr(h, vendor, type, str, strlen(str)));
}
ssize_t
rad_request_authenticator(struct rad_handle *h, char *buf, size_t len)
{
if (len < LEN_AUTH)
return (-1);
memcpy(buf, h->out + POS_AUTH, LEN_AUTH);
if (len > LEN_AUTH)
buf[LEN_AUTH] = '\0';
return (LEN_AUTH);
}
u_char *
rad_demangle(struct rad_handle *h, const void *mangled, size_t mlen)
{
char R[LEN_AUTH];
const char *S;
int i, Ppos;
MD5_CTX Context;
u_char b[MD5_DIGEST_LENGTH], *C, *demangled;
if ((mlen % 16 != 0) || mlen > 128) {
generr(h, "Cannot interpret mangled data of length %lu",
(u_long)mlen);
return NULL;
}
C = (u_char *)mangled;
/* We need the shared secret as Salt */
S = rad_server_secret(h);
/* We need the request authenticator */
if (rad_request_authenticator(h, R, sizeof R) != LEN_AUTH) {
generr(h, "Cannot obtain the RADIUS request authenticator");
return NULL;
}
demangled = malloc(mlen);
if (!demangled)
return NULL;
MD5Init(&Context);
MD5Update(&Context, S, strlen(S));
MD5Update(&Context, R, LEN_AUTH);
MD5Final(b, &Context);
Ppos = 0;
while (mlen) {
mlen -= 16;
for (i = 0; i < 16; i++)
demangled[Ppos++] = C[i] ^ b[i];
if (mlen) {
MD5Init(&Context);
MD5Update(&Context, S, strlen(S));
MD5Update(&Context, C, 16);
MD5Final(b, &Context);
}
C += 16;
}
return demangled;
}
u_char *
rad_demangle_mppe_key(struct rad_handle *h, const void *mangled,
size_t mlen, size_t *len)
{
char R[LEN_AUTH]; /* variable names as per rfc2548 */
const char *S;
u_char b[MD5_DIGEST_LENGTH], *demangled;
const u_char *A, *C;
MD5_CTX Context;
int Slen, i, Clen, Ppos;
u_char *P;
if (mlen % 16 != SALT_LEN) {
generr(h, "Cannot interpret mangled data of length %lu",
(u_long)mlen);
return NULL;
}
/* We need the RADIUS Request-Authenticator */
if (rad_request_authenticator(h, R, sizeof R) != LEN_AUTH) {
generr(h, "Cannot obtain the RADIUS request authenticator");
return NULL;
}
A = (const u_char *)mangled; /* Salt comes first */
C = (const u_char *)mangled + SALT_LEN; /* Then the ciphertext */
Clen = mlen - SALT_LEN;
S = rad_server_secret(h); /* We need the RADIUS secret */
Slen = strlen(S);
P = alloca(Clen); /* We derive our plaintext */
MD5Init(&Context);
MD5Update(&Context, S, Slen);
MD5Update(&Context, R, LEN_AUTH);
MD5Update(&Context, A, SALT_LEN);
MD5Final(b, &Context);
Ppos = 0;
while (Clen) {
Clen -= 16;
for (i = 0; i < 16; i++)
P[Ppos++] = C[i] ^ b[i];
if (Clen) {
MD5Init(&Context);
MD5Update(&Context, S, Slen);
MD5Update(&Context, C, 16);
MD5Final(b, &Context);
}
C += 16;
}
/*
* The resulting plain text consists of a one-byte length, the text and
* maybe some padding.
*/
*len = *P;
if (*len > mlen - 1) {
generr(h, "Mangled data seems to be garbage %zu %zu",
*len, mlen-1);
return NULL;
}
if (*len > MPPE_KEY_LEN * 2) {
generr(h, "Key to long (%zu) for me max. %d",
*len, MPPE_KEY_LEN * 2);
return NULL;
}
demangled = malloc(*len);
if (!demangled)
return NULL;
memcpy(demangled, P + 1, *len);
return demangled;
}
const char *
rad_server_secret(struct rad_handle *h)
{
return (h->servers[h->srv].secret);
}