/*
* This file is part of the Sofia-SIP package
*
* Copyright (C) 2005 Nokia Corporation.
*
* Contact: Pekka Pessi <pekka.pessi@nokia.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
*/
/**@CFILE auth_module.c
* @brief Authentication verification module
*
* The authentication module provides server or proxy-side authentication
* verification for network elements like registrars, presence servers, and
* proxies.
*
* @author Pekka Pessi <Pekka.Pessi@nokia.com>.
*
* @date Created: Wed Apr 11 15:14:03 2001 ppessi
*/
#include "config.h"
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <sofia-sip/auth_digest.h>
#include "iptsec_debug.h"
#if HAVE_FUNC
#elif HAVE_FUNCTION
#define __func__ __FUNCTION__
#else
static char const __func__[] = "auth_mod";
#endif
#include <sofia-sip/su_debug.h>
#include <sofia-sip/su_wait.h>
#include <sofia-sip/su_alloc.h>
#include <sofia-sip/su_string.h>
#include <sofia-sip/su_tagarg.h>
#include <sofia-sip/base64.h>
#include <sofia-sip/su_md5.h>
#include <sofia-sip/msg_parser.h>
#include <sofia-sip/msg_date.h>
#include "sofia-sip/auth_module.h"
#include "sofia-sip/auth_plugin.h"
#define APW_HASH(apw) ((apw)->apw_index)
char const auth_internal_server_error[] = "Internal server error";
static void auth_call_scheme_destructor(void *);
static void auth_md5_hmac_key(auth_mod_t *am);
#ifdef __clang__
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wunused-function"
#endif
HTABLE_PROTOS_WITH(auth_htable, aht, auth_passwd_t, usize_t, unsigned);
HTABLE_BODIES_WITH(auth_htable, aht, auth_passwd_t, APW_HASH,
usize_t, unsigned);
#ifdef __clang__
#pragma clang diagnostic pop
#endif
/**Allocate an authentication module instance.
*
* The function auth_mod_alloc() allocates an authentication module object.
*
*/
auth_mod_t *auth_mod_alloc(auth_scheme_t *scheme,
tag_type_t tag, tag_value_t value, ...)
{
auth_mod_t *am = NULL;
if ((am = su_home_new(scheme->asch_size))) {
am->am_scheme = scheme;
su_home_destructor(am->am_home, auth_call_scheme_destructor);
}
return am;
}
/**Initialize an authentication module instance.
*
* The function auth_mod_init_default() initializes an authentication module
* object used to authenticate the requests.
*
* @param am
* @param base
* @param root
* @param tag,value,... tagged argument list
*
* @TAGS
* AUTHTAG_REALM(), AUTHTAG_OPAQUE(), AUTHTAG_DB(), AUTHTAG_QOP(),
* AUTHTAG_ALGORITHM(), AUTHTAG_EXPIRES(), AUTHTAG_NEXT_EXPIRES(),
* AUTHTAG_BLACKLIST(), AUTHTAG_FORBIDDEN(), AUTHTAG_ANONYMOUS(),
* AUTHTAG_FAKE(), AUTHTAG_ALLOW(), AUTHTAG_REMOTE(), and
* AUTHTAG_MASTER_KEY().
*
* @return 0 if successful
* @return -1 upon an error
*/
int auth_init_default(auth_mod_t *am,
auth_scheme_t *base,
su_root_t *root,
tag_type_t tag, tag_value_t value, ...)
{
int retval = 0;
ta_list ta;
char const *realm = NULL, *opaque = NULL, *db = NULL, *allows = NULL;
char const *qop = NULL, *algorithm = NULL;
unsigned expires = 60 * 60, next_expires = 5 * 60;
unsigned max_ncount = 0;
unsigned blacklist = 5;
int forbidden = 0;
int anonymous = 0;
int fake = 0;
url_string_t const *remote = NULL;
char const *master_key = "fish";
char *s;
ta_start(ta, tag, value);
/* Authentication stuff */
tl_gets(ta_args(ta),
AUTHTAG_REALM_REF(realm),
AUTHTAG_OPAQUE_REF(opaque),
AUTHTAG_DB_REF(db),
AUTHTAG_QOP_REF(qop),
AUTHTAG_ALGORITHM_REF(algorithm),
AUTHTAG_EXPIRES_REF(expires),
AUTHTAG_NEXT_EXPIRES_REF(next_expires),
AUTHTAG_MAX_NCOUNT_REF(max_ncount),
AUTHTAG_BLACKLIST_REF(blacklist),
AUTHTAG_FORBIDDEN_REF(forbidden),
AUTHTAG_ANONYMOUS_REF(anonymous),
AUTHTAG_FAKE_REF(fake),
AUTHTAG_ALLOW_REF(allows),
AUTHTAG_REMOTE_REF(remote),
AUTHTAG_MASTER_KEY_REF(master_key),
TAG_NULL());
if (!realm) realm = "*";
if (!allows) allows = "ACK, BYE, CANCEL";
am->am_realm = su_strdup(am->am_home, realm);
am->am_opaque = su_strdup(am->am_home, opaque);
am->am_db = su_strdup(am->am_home, db);
s = su_strdup(am->am_home, allows);
if (s)
msg_commalist_d(am->am_home, &s, &am->am_allow, NULL);
am->am_expires = expires;
am->am_next_exp = next_expires;
am->am_max_ncount = max_ncount;
am->am_blacklist = blacklist;
am->am_forbidden = forbidden;
am->am_anonymous = anonymous;
am->am_fake = fake;
am->am_remote = url_hdup(am->am_home, (url_t *)remote);
am->am_algorithm = algorithm ? su_strdup(am->am_home, algorithm) : "MD5";
am->am_nextnonce = !algorithm || su_casematch(algorithm, "MD5");
if (next_expires == 0)
am->am_nextnonce = 0;
am->am_qop = su_strdup(am->am_home, qop);
if (master_key) {
su_md5_t md5[1];
su_md5_init(md5);
su_md5_strupdate(md5, master_key);
su_md5_strupdate(md5, "70P 53KR37");
su_md5_digest(md5, am->am_master_key);
}
auth_md5_hmac_key(am);
/* Make sure that we have something
that can be used to identify credentials */
if (am->am_opaque && strcmp(am->am_opaque, "*") == 0) {
#ifndef HOST_NAME_MAX
#define HOST_NAME_MAX 255
#endif
char hostname[HOST_NAME_MAX + 1];
su_md5_t md5[1];
uint8_t hmac[6];
gethostname(hostname, sizeof hostname);
auth_md5_hmac_init(am, md5);
su_md5_strupdate(md5, hostname);
su_md5_update(md5, ":", 1);
if (am->am_remote)
url_update(md5, am->am_remote);
auth_md5_hmac_digest(am, md5, hmac, sizeof hmac);
base64_e(hostname, sizeof hostname, hmac, sizeof hmac);
am->am_opaque = su_strdup(am->am_home, hostname);
if (!am->am_opaque) {
retval = -1;
SU_DEBUG_1(("%s: cannot create unique identifier\n", __func__));
}
}
if (retval < 0)
;
else if (db) {
retval = auth_readdb(am);
if (retval == -1) {
int err = errno;
SU_DEBUG_1(("auth-module: %s: %s\n", am->am_db, strerror(err)));
errno = err;
}
}
else {
retval = auth_htable_resize(am->am_home, am->am_users, 0);
}
ta_end(ta);
return retval;
}
/** Destroy (a reference to) an authentication module. */
void auth_mod_destroy(auth_mod_t *am)
{
su_home_unref(am->am_home);
}
/** Call scheme-specific destructor function. */
static void auth_call_scheme_destructor(void *arg)
{
auth_mod_t *am = arg;
am->am_scheme->asch_destroy(am);
}
/** Do-nothing destroy function.
*
* The auth_destroy_default() is the default member function called by
* auth_mod_destroy().
*/
void auth_destroy_default(auth_mod_t *am)
{
}
/** Create a new reference to authentication module. */
auth_mod_t *auth_mod_ref(auth_mod_t *am)
{
return (auth_mod_t *)su_home_ref(am->am_home);
}
/** Destroy a reference to an authentication module. */
void auth_mod_unref(auth_mod_t *am)
{
su_home_unref(am->am_home);
}
/** Get authenticatin module name. @NEW_1_12_4. */
char const *auth_mod_name(auth_mod_t *am)
{
return am ? am->am_scheme->asch_method : "<nil>";
}
/** Initialize a auth_status_t stucture.
*
* @retval NULL upon an error
* @relates auth_status_t
*/
auth_status_t *auth_status_init(void *p, isize_t size)
{
return auth_status_init_with(p, size, 500, auth_internal_server_error);
}
/** Initialize a auth_status_t stucture.
*
* @retval NULL upon an error
* @relates auth_status_t
*/
auth_status_t *auth_status_init_with(void *p,
isize_t size,
int status,
char const *phrase)
{
auth_status_t *as;
if (!p || size < (sizeof *as))
return NULL;
if (size > INT_MAX) size = INT_MAX;
as = memset(p, 0, size);
as->as_home->suh_size = (int)size;
/* su_home_init(as->as_home); */
as->as_status = status, as->as_phrase = phrase;
return as;
}
/** Allocate a new auth_status_t structure. @relates auth_status_t */
auth_status_t *auth_status_new(su_home_t *home)
{
auth_status_t *as = su_home_clone(home, (sizeof *as));
if (as) {
as->as_status = 500;
as->as_phrase = auth_internal_server_error;
}
return as;
}
/** Create a new reference to an auth_status_t structure.
* @relates auth_status_t
*/
auth_status_t *auth_status_ref(auth_status_t *as)
{
return (auth_status_t *)su_home_ref(as->as_home);
}
/** Destroy (a reference to) an auth_status_t structure. @relates auth_status_t
*/
void auth_status_unref(auth_status_t *as)
{
su_home_unref(as->as_home);
}
/** Authenticate user.
*
* The function auth_mod_method() invokes scheme-specific authentication
* operation where the user's credentials are checked using scheme-specific
* method. The authentication result along with an optional challenge header
* is stored in the @a as structure.
*
* @param am pointer to authentication module object [in]
* @param as pointer to authentication status structure [in/out]
* @param credentials pointer to a header with user's credentials [in]
* @param ach pointer to a structure describing challenge [in]
*
* The @a ach structure defines what kind of response and challenge header
* is returned to the user. For example, a server authentication is
* implemented with 401 response code and phrase along with WWW-Authenticate
* header template in the @a ach structure.
*
* The auth_mod_method() returns the authentication result in the
* #auth_mod_t @a as structure. The @a as->as_status describes the result
* as follows:
* - <i>as->as_status == 0</i> authentication is successful
* - <i>as->as_status == 100</i> authentication is pending
* - <i>as->as_status >= 400</i> authentication fails,
* return as_status as an error code to client
*
* When the authentication is left pending, the client must set the
* as_callback pointer in @a as structure to an appropriate callback
* function. The callback is invoked when the authentication is completed,
* either successfully or with an error.
*
* Note that the authentication module may generate a new challenge each
* time authentication is used (e.g., Digest using MD5 algorithm). Such a
* challenge header is stored in the @a as->as_response return-value field.
*
* @note The authentication plugin may use the given reference to @a as, @a
* credentials and @a ach structures until the asynchronous authentication
* completes. Therefore, they should not be allocated from stack unless
* application uses strictly synchronous authentication schemes only (Basic
* and Digest).
*
* @note This function should be called auth_mod_check().
*/
void auth_mod_verify(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *credentials,
auth_challenger_t const *ach)
{
char const *wildcard, *host;
if (!am || !as || !ach)
return;
wildcard = strchr(am->am_realm, '*');
host = as->as_domain;
/* Initialize per-request realm */
if (as->as_realm)
;
else if (!wildcard) {
as->as_realm = am->am_realm;
}
else if (!host) {
return; /* Internal error */
}
else if (strcmp(am->am_realm, "*") == 0) {
as->as_realm = host;
}
else {
/* Replace * with hostpart */
as->as_realm = su_sprintf(as->as_home, "%.*s%s%s",
(int)(wildcard - am->am_realm), am->am_realm,
host,
wildcard + 1);
}
am->am_scheme->asch_check(am, as, credentials, ach);
}
/** Make a challenge header.
*
* This function invokes plugin-specific member function generating a
* challenge header. Client uses the challenge header contents when
* prompting the user for a username and password then generates its
* credential header using the parameters given in the challenge header.
*
* @param am pointer to authentication module object
* @param as pointer to authentication status structure (return-value)
* @param ach pointer to a structure describing challenge
*
* The auth_mod_challenge() returns the challenge header, appropriate
* response code and reason phrase in the #auth_status_t structure. The
* auth_mod_challenge() is currently always synchronous function.
*/
void auth_mod_challenge(auth_mod_t *am,
auth_status_t *as,
auth_challenger_t const *ach)
{
if (am && as && ach)
am->am_scheme->asch_challenge(am, as, ach);
}
/** Cancel asynchronous authentication.
*
* The auth_mod_cancel() function cancels a pending authentication.
* Application can reclaim the authentication status, credential and
* challenger objects by using auth_mod_cancel().
*/
void auth_mod_cancel(auth_mod_t *am, auth_status_t *as)
{
if (am && as)
am->am_scheme->asch_cancel(am, as);
}
/** Do-nothing cancel function.
*
* The auth_cancel_default() is the default member function called by
* auth_mod_cancel().
*/
void auth_cancel_default(auth_mod_t *am, auth_status_t *as)
{
}
/* ====================================================================== */
/* Basic authentication scheme */
static void auth_method_basic_x(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *au,
auth_challenger_t const *ach);
auth_scheme_t auth_scheme_basic[1] =
{{
"Basic", /* asch_method */
sizeof (auth_mod_t), /* asch_size */
auth_init_default, /* asch_init */
auth_method_basic_x, /* asch_check */
auth_challenge_basic, /* asch_challenge */
auth_cancel_default, /* asch_cancel */
auth_destroy_default /* asch_destroy */
}};
/**Authenticate a request with @b Basic authentication.
*
* This function reads user database before authentication, if needed.
*/
static
void auth_method_basic_x(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *au,
auth_challenger_t const *ach)
{
if (am) {
auth_readdb_if_needed(am);
auth_method_basic(am, as, au, ach);
}
}
/** Authenticate a request with @b Basic authentication scheme.
*
*/
void auth_method_basic(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *au,
auth_challenger_t const *ach)
{
char *userpass, buffer[128];
size_t n, upsize;
char *pass;
auth_passwd_t *apw;
if (!as->as_realm)
return;
userpass = buffer, upsize = sizeof buffer;
for (au = auth_mod_credentials(au, "Basic", NULL);
au;
au = auth_mod_credentials(au->au_next, "Basic", NULL)) {
if (!au->au_params)
continue;
n = base64_d(userpass, upsize - 1, au->au_params[0]);
if (n >= upsize) {
void *b = realloc(userpass == buffer ? NULL : userpass, upsize = n + 1);
if (b == NULL)
break;
base64_d(userpass = b, upsize - 1, au->au_params[0]);
}
userpass[n] = 0;
if (!(pass = strchr(userpass, ':')))
continue;
*pass++ = '\0';
SU_DEBUG_5(("auth_method_basic: %s => %s:%s\n",
au->au_params[0], userpass, pass));
if (!(apw = auth_mod_getpass(am, userpass, as->as_realm)))
continue;
if (strcmp(apw->apw_pass, pass))
continue;
as->as_user = apw->apw_user;
as->as_anonymous = apw == am->am_anon_user;
as->as_ident = apw->apw_ident;
as->as_match = (msg_header_t *)au;
as->as_status = 0; /* Successful authentication! */
break;
}
if (userpass != buffer)
free(userpass);
if (au)
return;
if (auth_allow_check(am, as))
auth_challenge_basic(am, as, ach);
}
/** Construct a challenge header for @b Basic authentication scheme. */
void auth_challenge_basic(auth_mod_t *am,
auth_status_t *as,
auth_challenger_t const *ach)
{
as->as_status = ach->ach_status;
as->as_phrase = ach->ach_phrase;
as->as_response = msg_header_format(as->as_home, ach->ach_header,
"Basic realm=\"%s\"", as->as_realm);
}
/* ====================================================================== */
/* Digest authentication scheme */
static void auth_method_digest_x(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *au,
auth_challenger_t const *ach);
auth_scheme_t auth_scheme_digest[1] =
{{
"Digest", /* asch_method */
sizeof (auth_mod_t), /* asch_size */
auth_init_default, /* asch_init */
auth_method_digest_x, /* asch_check */
auth_challenge_digest, /* asch_challenge */
auth_cancel_default, /* asch_cancel */
auth_destroy_default /* asch_destroy */
}};
struct nonce {
msg_time_t issued;
uint32_t count;
uint16_t nextnonce;
uint8_t digest[6];
};
#define AUTH_DIGEST_NONCE_LEN (BASE64_MINSIZE(sizeof (struct nonce)) + 1)
/** Authenticate a request with @b Digest authentication scheme.
*
* This function reads user database before authentication, if needed.
*/
static
void auth_method_digest_x(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *au,
auth_challenger_t const *ach)
{
if (am) {
auth_readdb_if_needed(am);
auth_method_digest(am, as, au, ach);
}
}
/** Authenticate a request with @b Digest authentication scheme.
*/
void auth_method_digest(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *au,
auth_challenger_t const *ach)
{
as->as_allow = as->as_allow || auth_allow_check(am, as) == 0;
if (as->as_realm)
au = auth_digest_credentials(au, as->as_realm, am->am_opaque);
else
au = NULL;
if (as->as_allow) {
SU_DEBUG_5(("%s: allow unauthenticated %s\n", __func__, as->as_method));
as->as_status = 0, as->as_phrase = NULL;
as->as_match = (msg_header_t *)au;
return;
}
if (au) {
auth_response_t ar[1] = {{ sizeof(ar) }};
auth_digest_response_get(as->as_home, ar, au->au_params);
as->as_match = (msg_header_t *)au;
auth_check_digest(am, as, ar, ach);
}
else {
/* There was no matching credentials, send challenge */
SU_DEBUG_5(("%s: no credentials matched\n", __func__));
auth_challenge_digest(am, as, ach);
}
}
/** Verify digest authentication */
void auth_check_digest(auth_mod_t *am,
auth_status_t *as,
auth_response_t *ar,
auth_challenger_t const *ach)
{
char const *a1;
auth_hexmd5_t a1buf, response;
auth_passwd_t *apw;
char const *phrase;
msg_time_t now = msg_now();
if (am == NULL || as == NULL || ar == NULL || ach == NULL) {
if (as) {
as->as_status = 500, as->as_phrase = "Internal Server Error";
as->as_response = NULL;
}
return;
}
phrase = "Bad authorization";
#define PA "Authorization missing "
if ((!ar->ar_username && (phrase = PA "username")) ||
(!ar->ar_nonce && (phrase = PA "nonce")) ||
(!ar->ar_uri && (phrase = PA "URI")) ||
(!ar->ar_response && (phrase = PA "response")) ||
/* (!ar->ar_opaque && (phrase = PA "opaque")) || */
/* Check for qop */
(ar->ar_qop &&
((ar->ar_auth &&
!su_casematch(ar->ar_qop, "auth") &&
!su_casematch(ar->ar_qop, "\"auth\"")) ||
(ar->ar_auth_int &&
!su_casematch(ar->ar_qop, "auth-int") &&
!su_casematch(ar->ar_qop, "\"auth-int\"")))
&& (phrase = PA "has invalid qop"))) {
assert(phrase);
SU_DEBUG_5(("auth_method_digest: 400 %s\n", phrase));
as->as_status = 400, as->as_phrase = phrase;
as->as_response = NULL;
return;
}
if (as->as_nonce_issued == 0 /* Already validated nonce */ &&
auth_validate_digest_nonce(am, as, ar, now) < 0) {
as->as_blacklist = am->am_blacklist;
auth_challenge_digest(am, as, ach);
return;
}
if (as->as_stale) {
auth_challenge_digest(am, as, ach);
return;
}
apw = auth_mod_getpass(am, ar->ar_username, ar->ar_realm);
if (apw && apw->apw_hash)
a1 = apw->apw_hash;
else if (apw && apw->apw_pass)
auth_digest_a1(ar, a1buf, apw->apw_pass), a1 = a1buf;
else
auth_digest_a1(ar, a1buf, "xyzzy"), a1 = a1buf, apw = NULL;
if (ar->ar_md5sess)
auth_digest_a1sess(ar, a1buf, a1), a1 = a1buf;
auth_digest_response(ar, response, a1,
as->as_method, as->as_body, as->as_bodylen);
if (!apw || strcmp(response, ar->ar_response)) {
if (am->am_forbidden) {
as->as_status = 403, as->as_phrase = "Forbidden";
as->as_response = NULL;
as->as_blacklist = am->am_blacklist;
}
else {
auth_challenge_digest(am, as, ach);
as->as_blacklist = am->am_blacklist;
}
SU_DEBUG_5(("auth_method_digest: response did not match\n" VA_NONE));
return;
}
assert(apw);
as->as_user = apw->apw_user;
as->as_anonymous = apw == am->am_anon_user;
as->as_ident = apw->apw_ident;
if (am->am_nextnonce || am->am_mutual)
auth_info_digest(am, as, ach);
if (am->am_challenge)
auth_challenge_digest(am, as, ach);
SU_DEBUG_7(("auth_method_digest: successful authentication\n" VA_NONE));
as->as_status = 0; /* Successful authentication! */
as->as_phrase = "";
}
/** Construct a challenge header for @b Digest authentication scheme. */
void auth_challenge_digest(auth_mod_t *am,
auth_status_t *as,
auth_challenger_t const *ach)
{
char const *u, *d;
char nonce[AUTH_DIGEST_NONCE_LEN];
auth_generate_digest_nonce(am, nonce, sizeof nonce, 0, msg_now());
u = as->as_uri;
d = as->as_pdomain;
as->as_response =
msg_header_format(as->as_home, ach->ach_header,
"Digest"
" realm=\"%s\","
"%s%s%s"
"%s%s%s"
" nonce=\"%s\","
"%s%s%s"
"%s" /* stale */
" algorithm=%s"
"%s%s%s",
as->as_realm,
u ? " uri=\"" : "", u ? u : "", u ? "\"," : "",
d ? " domain=\"" : "", d ? d : "", d ? "\"," : "",
nonce,
am->am_opaque ? " opaque=\"" : "",
am->am_opaque ? am->am_opaque : "",
am->am_opaque ? "\"," : "",
as->as_stale ? " stale=true," : "",
am->am_algorithm,
am->am_qop ? ", qop=\"" : "",
am->am_qop ? am->am_qop : "",
am->am_qop ? "\"" : "");
if (!as->as_response)
as->as_status = 500, as->as_phrase = auth_internal_server_error;
else
as->as_status = ach->ach_status, as->as_phrase = ach->ach_phrase;
}
/** Construct a info header for @b Digest authentication scheme. */
void auth_info_digest(auth_mod_t *am,
auth_status_t *as,
auth_challenger_t const *ach)
{
if (!ach->ach_info)
return;
if (am->am_nextnonce) {
char nonce[AUTH_DIGEST_NONCE_LEN];
auth_generate_digest_nonce(am, nonce, sizeof nonce, 1, msg_now());
as->as_info =
msg_header_format(as->as_home, ach->ach_info, "nextnonce=\"%s\"", nonce);
}
}
/* ====================================================================== */
/* Password database */
su_inline void
auth_htable_append_local(auth_htable_t *pr, auth_passwd_t *apw);
/** Get an passwd entry for user. */
auth_passwd_t *auth_mod_getpass(auth_mod_t *am,
char const *user,
char const *realm)
{
auth_passwd_t *apw, **slot;
unsigned hash;
if (am == NULL || user == NULL)
return NULL;
hash = msg_hash_string(user);
for (slot = auth_htable_hash(am->am_users, hash);
(apw = *slot);
slot = auth_htable_next(am->am_users, slot)) {
if (hash != apw->apw_index)
continue;
if (strcmp(user, apw->apw_user))
continue;
if (realm && apw->apw_realm[0] && strcmp(realm, apw->apw_realm))
continue;
break; /* Found it */
}
return apw;
}
/** Add a password entry. */
auth_passwd_t *auth_mod_addpass(auth_mod_t *am,
char const *user,
char const *realm)
{
auth_passwd_t *apw, **slot;
unsigned index;
if (am == NULL || user == NULL)
return NULL;
index = msg_hash_string(user);
for (slot = auth_htable_hash(am->am_users, index);
(apw = *slot);
slot = auth_htable_next(am->am_users, slot)) {
if (index != apw->apw_index)
continue;
if (strcmp(user, apw->apw_user))
continue;
if (realm && strcmp(realm, apw->apw_realm))
continue;
break; /* Found it */
}
if (realm == NULL)
realm = "";
if (!apw) {
size_t ulen = strlen(user) + 1, rlen = strlen(realm) + 1;
size_t size = sizeof *apw + ulen + rlen;
apw = su_alloc(am->am_home, size);
if (apw) {
memset(apw, 0, sizeof *apw);
apw->apw_index = index;
apw->apw_user = memcpy((char *)(apw + 1), user, ulen);
apw->apw_realm = memcpy((char *)apw->apw_user + ulen, realm, rlen);
if (!auth_htable_is_full(am->am_users)) {
*slot = apw, am->am_users->aht_used++;
} else {
if (auth_htable_resize(am->am_home, am->am_users, 0) < 0)
su_free(am->am_home, apw), apw = NULL;
else
auth_htable_append(am->am_users, apw);
}
}
}
return apw;
}
static ssize_t readfile(su_home_t *, FILE *,
void **contents, int add_trailing_lf);
static int auth_readdb_internal(auth_mod_t *am, int always);
/** Read authentication database */
int auth_readdb(auth_mod_t *am)
{
return auth_readdb_internal(am, 1);
}
/** Read authentication database only when needed */
int auth_readdb_if_needed(auth_mod_t *am)
{
struct stat st[1];
if (!am->am_stat || !am->am_db)
return 0;
if (stat(am->am_db, st) != -1 &&
st->st_dev == am->am_stat->st_dev &&
st->st_ino == am->am_stat->st_ino &&
st->st_size == am->am_stat->st_size &&
memcmp(&st->st_mtime, &am->am_stat->st_mtime,
(sizeof st->st_mtime)) == 0)
/* Nothing has changed or passwd file is removed */
return 0;
return auth_readdb_internal(am, 0);
}
#if HAVE_FLOCK
#include <sys/file.h>
#endif
/* This is just a magic value */
#define auth_apw_local ((void *)(intptr_t)auth_readdb_internal)
/** Read authentication database */
static
int auth_readdb_internal(auth_mod_t *am, int always)
{
FILE *f;
char *data, *s;
size_t len, i, n, N;
ssize_t slen;
auth_passwd_t *apw;
if (!am->am_stat)
am->am_stat = su_zalloc(am->am_home, sizeof (*am->am_stat));
f = fopen(am->am_db, "rb");
if (f) {
void *buffer = NULL;
auth_passwd_t *fresh = NULL;
#if HAVE_FLOCK
int locked;
/* Obtain shared lock on the database file */
if (flock(fileno(f), LOCK_SH | (always ? 0 : LOCK_NB)) == 0) {
locked = 1;
} else {
locked = 0;
if (errno == ENOLCK) {
;
}
else if (errno == EWOULDBLOCK) {
SU_DEBUG_3(("auth(%s): user file \"%s\" is busy, trying again later\n",
am->am_scheme->asch_method, am->am_db));
fclose(f);
return always ? -1 : 0;
}
else {
SU_DEBUG_3(("auth(%s): flock(\"%s\"): %s (%u)\n",
am->am_scheme->asch_method, am->am_db,
strerror(errno), errno));
fclose(f);
return always ? -1 : 0;
}
}
#endif
if (am->am_stat)
stat(am->am_db, am->am_stat); /* too bad if this fails */
slen = readfile(am->am_home, f, &buffer, 1);
#if HAVE_FLOCK
/* Release shared lock on the database file */
if (locked && flock(fileno(f), LOCK_UN) == -1) {
SU_DEBUG_0(("auth(%s): un-flock(\"%s\"): %s (%u)\n",
am->am_scheme->asch_method, am->am_db, strerror(errno), errno));
fclose(f);
return -1;
}
#endif
fclose(f);
if (slen < 0)
return -1;
len = (size_t)slen;
/* Count number of entries in new buffer */
for (i = am->am_anonymous, s = data = buffer;
s < data + len;
s += n + strspn(s + n, "\r\n")) {
n = strcspn(s, "\r\n");
if (*s != '#' && *s != '\n' && *s != '\r')
i++;
}
N = i, i = 0;
if (N > 0) {
size_t size = (N * 5 + 3) / 4;
if (auth_htable_resize(am->am_home, am->am_users, size) < 0 ||
!(fresh = su_zalloc(am->am_home, sizeof(*fresh) * N))) {
su_free(am->am_home, buffer);
return -1;
}
}
if (am->am_anonymous) {
assert(i < N);
apw = fresh + i++;
apw->apw_index = msg_hash_string("anonymous");
apw->apw_user = "anonymous";
apw->apw_pass = "";
apw->apw_realm = "";
am->am_anon_user = apw;
if (auth_htable_is_full(am->am_users))
auth_htable_resize(am->am_home, am->am_users, 0);
auth_htable_append_local(am->am_users, apw);
}
apw = NULL;
for (data = buffer, s = data;
s < data + len && i < N;
s += n + strspn(s + n, "\r\n")) {
char *user, *pass, *realm, *ident;
n = strcspn(s, "\r\n");
if (*s == '#')
continue;
user = s;
s[n++] = '\0';
if (!(pass = strchr(user, ':')))
continue;
*pass++ = '\0';
if (!*pass || !*user)
continue;
if ((realm = strchr(pass, ':')))
*realm++ = '\0';
else
realm = "";
if ((ident = strchr(realm, ':')))
*ident++ = '\0';
else
ident = "";
apw = fresh + i++;
apw->apw_index = msg_hash_string(user);
apw->apw_user = user;
apw->apw_ident = ident;
/* Check for htdigest format */
if (span_hexdigit(realm) == 32 && realm[32] == '\0') {
apw->apw_realm = pass;
apw->apw_hash = realm;
} else {
apw->apw_pass = pass;
apw->apw_realm = realm;
}
if (auth_htable_is_full(am->am_users))
auth_htable_resize(am->am_home, am->am_users, 0);
auth_htable_append_local(am->am_users, apw);
}
assert(i <= N);
N = i;
/* Remove from hash those entries that were read from old passwd file */
for (i = 0; i < am->am_local_count; i++) {
if (am->am_locals[i].apw_type == auth_apw_local)
auth_htable_remove(am->am_users, &am->am_locals[i]);
}
if (am->am_locals)
su_free(am->am_home, am->am_locals); /* Free old entries */
if (am->am_buffer)
su_free(am->am_home, am->am_buffer); /* Free old passwd file contents */
SU_DEBUG_5(("auth(%s): read %u entries from \"%s\"\n",
am->am_scheme->asch_method, (unsigned)N, am->am_db));
am->am_locals = fresh;
am->am_local_count = N;
am->am_buffer = buffer;
return 0;
}
return -1;
}
/** Append to hash, remove existing local user */
su_inline void
auth_htable_append_local(auth_htable_t *aht, auth_passwd_t *apw)
{
auth_passwd_t **slot;
apw->apw_type = auth_apw_local;
/* Append to hash */
for (slot = auth_htable_hash(aht, apw->apw_index);
*slot;
slot = auth_htable_next(aht, slot)) {
if (strcmp((*slot)->apw_user, apw->apw_user) == 0) {
if ((*slot)->apw_type == auth_apw_local) {
(*slot)->apw_type = NULL;
assert(aht->aht_used > 0); aht->aht_used--;
apw->apw_extended = (*slot)->apw_extended;
*slot = NULL;
break;
}
else {
/* We insert local before external entry */
auth_passwd_t *swap = apw;
apw = *slot;
*slot = swap;
}
}
}
aht->aht_used++; assert(aht->aht_used <= aht->aht_size);
*slot = apw;
}
static
ssize_t readfile(su_home_t *home,
FILE *f,
void **contents,
int add_trailing_lf)
{
/* Read in whole (binary!) file */
char *buffer = NULL;
long size;
size_t len;
/* Read whole file in */
if (fseek(f, 0, SEEK_END) < 0 ||
(size = ftell(f)) < 0 ||
fseek(f, 0, SEEK_SET) < 0 ||
(long)(len = (size_t)size) != size ||
size + 2 > SSIZE_MAX) {
SU_DEBUG_1(("%s: unable to determine file size (%s)\n",
__func__, strerror(errno)));
return -1;
}
if (!(buffer = su_alloc(home, len + 2)) ||
fread(buffer, 1, len, f) != len) {
SU_DEBUG_1(("%s: unable to read file (%s)\n", __func__, strerror(errno)));
if (buffer)
su_free(home, buffer);
return -1;
}
if (add_trailing_lf) {
/* Make sure that the buffer has trailing newline */
if (len == 0 || buffer[len - 1] != '\n')
buffer[len++] = '\n';
}
buffer[len] = '\0';
*contents = buffer;
return (ssize_t)len;
}
/* ====================================================================== */
/* Helper functions */
/** Check if request method is on always-allowed list.
*
* @return 0 if allowed
* @return 1 otherwise
*/
int auth_allow_check(auth_mod_t *am, auth_status_t *as)
{
char const *method = as->as_method;
int i;
if (method && strcmp(method, "ACK") == 0) /* Hack */
return as->as_status = 0;
if (!method || !am->am_allow)
return 1;
if (am->am_allow[0] && strcmp(am->am_allow[0], "*") == 0)
return as->as_status = 0;
for (i = 0; am->am_allow[i]; i++)
if (strcmp(am->am_allow[i], method) == 0)
return as->as_status = 0;
return 1;
}
/** Find a credential header with matching scheme and realm. */
msg_auth_t *auth_mod_credentials(msg_auth_t *auth,
char const *scheme,
char const *realm)
{
char const *arealm;
for (;auth; auth = auth->au_next) {
if (!su_casematch(auth->au_scheme, scheme))
continue;
if (!realm)
return auth;
arealm = msg_header_find_param(auth->au_common, "realm=");
if (!arealm)
continue;
if (arealm[0] == '"') {
/* Compare quoted arealm with unquoted realm */
int i, j;
for (i = 1, j = 0; arealm[i] != 0; i++, j++) {
if (arealm[i] == '"' && realm[j] == 0)
return auth;
if (arealm[i] == '\\' && arealm[i + 1] != '\0')
i++;
if (arealm[i] != realm[j])
break;
}
} else {
if (strcmp(arealm, realm) == 0)
return auth;
}
}
return NULL;
}
/** Find a Digest credential header with matching realm and opaque. */
msg_auth_t *auth_digest_credentials(msg_auth_t *auth,
char const *realm,
char const *opaque)
{
char const *arealm, *aopaque;
for (;auth; auth = auth->au_next) {
if (!su_casematch(auth->au_scheme, "Digest"))
continue;
if (realm) {
int cmp = 1;
arealm = msg_header_find_param(auth->au_common, "realm=");
if (!arealm)
continue;
if (arealm[0] == '"') {
/* Compare quoted arealm with unquoted realm */
int i, j;
for (i = 1, j = 0, cmp = 1; arealm[i] != 0; i++, j++) {
if (arealm[i] == '"' && realm[j] == 0) {
cmp = 0;
break;
}
if (arealm[i] == '\\' && arealm[i + 1] != '\0')
i++;
if (arealm[i] != realm[j])
break;
}
}
else {
cmp = strcmp(arealm, realm);
}
if (cmp)
continue;
}
if (opaque) {
int cmp = 1;
aopaque = msg_header_find_param(auth->au_common, "opaque=");
if (!aopaque)
continue;
if (aopaque[0] == '"') {
/* Compare quoted aopaque with unquoted opaque */
int i, j;
for (i = 1, j = 0, cmp = 1; aopaque[i] != 0; i++, j++) {
if (aopaque[i] == '"' && opaque[j] == 0) {
cmp = 0;
break;
}
if (aopaque[i] == '\\' && aopaque[i + 1] != '\0')
i++;
if (aopaque[i] != opaque[j])
break;
}
} else {
cmp = strcmp(aopaque, opaque);
}
if (cmp)
continue;
}
return auth;
}
return NULL;
}
/** Generate nonce parameter.
*
* @param am pointer to authentication module object
* @param buffer string buffer for nonce [OUT]
* @param bsize size of buffer [IN]
* @param nextnonce true if this is a "nextnonce" [IN]
* @param now current time [IN]
*/
isize_t auth_generate_digest_nonce(auth_mod_t *am,
char buffer[],
size_t bsize,
int nextnonce,
msg_time_t now)
{
struct nonce nonce[1] = {{ 0 }};
su_md5_t md5[1];
am->am_count += 3730029547U; /* 3730029547 is a prime */
nonce->issued = now;
nonce->count = am->am_count;
nonce->nextnonce = nextnonce != 0;
/* Calculate HMAC of nonce data */
auth_md5_hmac_init(am, md5);
su_md5_update(md5, nonce, offsetof(struct nonce, digest));
auth_md5_hmac_digest(am, md5, nonce->digest, sizeof nonce->digest);
return base64_e(buffer, bsize, nonce, sizeof(nonce));
}
/** Validate nonce parameter.
*
* @param am pointer to authentication module object
* @param as authentication status structure [OUT]
* @param ar decoded authentication response from client [IN]
* @param now current time [IN]
*/
int auth_validate_digest_nonce(auth_mod_t *am,
auth_status_t *as,
auth_response_t *ar,
msg_time_t now)
{
struct nonce nonce[1] = {{ 0 }};
su_md5_t md5[1];
uint8_t hmac[sizeof nonce->digest];
unsigned expires;
/* Check nonce */
if (!ar->ar_nonce) {
SU_DEBUG_5(("auth_method_digest: no nonce\n" VA_NONE));
return -1;
}
if (base64_d((void*)nonce, (sizeof nonce), ar->ar_nonce) != (sizeof nonce)) {
SU_DEBUG_5(("auth_method_digest: too short nonce\n" VA_NONE));
return -1;
}
/* Calculate HMAC over decoded nonce data */
auth_md5_hmac_init(am, md5);
su_md5_update(md5, nonce, offsetof(struct nonce, digest));
auth_md5_hmac_digest(am, md5, hmac, sizeof hmac);
if (memcmp(nonce->digest, hmac, sizeof nonce->digest)) {
SU_DEBUG_5(("auth_method_digest: bad nonce\n" VA_NONE));
return -1;
}
as->as_nonce_issued = nonce->issued;
as->as_nextnonce = nonce->nextnonce != 0;
expires = nonce->nextnonce ? am->am_next_exp : am->am_expires;
if (nonce->issued > now ||
(expires && nonce->issued + expires < now)) {
SU_DEBUG_5(("auth_method_digest: nonce expired %lu seconds ago "
"(lifetime %u)\n",
now - (nonce->issued + expires), expires));
as->as_stale = 1;
}
if (am->am_max_ncount && ar->ar_nc) {
unsigned long nc = strtoul(ar->ar_nc, NULL, 10);
if (nc == 0 || nc > am->am_max_ncount) {
SU_DEBUG_5(("auth_method_digest: nonce used %s times, max %u\n",
ar->ar_nc, am->am_max_ncount));
as->as_stale = 1;
}
}
/* We should also check cnonce, nc... */
return 0;
}
/* ====================================================================== */
/* HMAC routines */
static
void auth_md5_hmac_key(auth_mod_t *am)
{
size_t i;
uint8_t ipad[SU_MD5_DIGEST_SIZE];
uint8_t opad[SU_MD5_DIGEST_SIZE];
assert(SU_MD5_DIGEST_SIZE == sizeof am->am_master_key);
/* Derive HMAC ipad and opad from master key */
for (i = 0; i < sizeof am->am_master_key; i++) {
ipad[i] = am->am_master_key[i] ^ 0x36;
opad[i] = am->am_master_key[i] ^ 0x5C;
}
/* Pre-calculate sum of ipad */
su_md5_init(&am->am_hmac_ipad);
su_md5_update(&am->am_hmac_ipad, ipad, sizeof ipad);
/* Pre-calculate sum of opad */
su_md5_init(&am->am_hmac_opad);
su_md5_update(&am->am_hmac_opad, opad, sizeof opad);
}
void auth_md5_hmac_init(auth_mod_t *am, struct su_md5_t *imd5)
{
*imd5 = am->am_hmac_ipad;
}
void auth_md5_hmac_digest(auth_mod_t *am, struct su_md5_t *imd5,
void *hmac, size_t size)
{
uint8_t digest[SU_MD5_DIGEST_SIZE];
su_md5_t omd5[1];
/* inner sum */
su_md5_digest(imd5, digest);
*omd5 = am->am_hmac_opad;
su_md5_update(omd5, digest, sizeof *digest);
/* outer sum */
if (size == sizeof digest) {
su_md5_digest(omd5, hmac);
}
else {
su_md5_digest(omd5, digest);
if (size > sizeof digest) {
memset((char *)hmac + (sizeof digest), 0, size - sizeof digest);
size = sizeof digest;
}
memcpy(hmac, digest, size);
}
}
/* ====================================================================== */
/* Compatibility interface */
void auth_mod_method(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *credentials,
auth_challenger_t const *ach)
{
auth_mod_verify(am, as, credentials, ach);
}
void auth_mod_check_client(auth_mod_t *am,
auth_status_t *as,
msg_auth_t *credentials,
auth_challenger_t const *ach)
{
auth_mod_verify(am, as, credentials, ach);
}
void auth_mod_challenge_client(auth_mod_t *am,
auth_status_t *as,
auth_challenger_t const *ach)
{
auth_mod_challenge(am, as, ach);
}