boringssl/crypto/x509/by_dir.c
David Benjamin 17cf2cb1d2 Work around language and compiler bug in memcpy, etc.
Most C standard library functions are undefined if passed NULL, even
when the corresponding length is zero. This gives them (and, in turn,
all functions which call them) surprising behavior on empty arrays.
Some compilers will miscompile code due to this rule. See also
https://www.imperialviolet.org/2016/06/26/nonnull.html

Add OPENSSL_memcpy, etc., wrappers which avoid this problem.

BUG=23

Change-Id: I95f42b23e92945af0e681264fffaf578e7f8465e
Reviewed-on: https://boringssl-review.googlesource.com/12928
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2016-12-21 20:34:47 +00:00

454 lines
15 KiB
C

/* crypto/x509/by_dir.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* 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 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.] */
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <openssl/buf.h>
#include <openssl/err.h>
#include <openssl/lhash.h>
#include <openssl/mem.h>
#include <openssl/thread.h>
#include <openssl/x509.h>
#include "../internal.h"
typedef struct lookup_dir_hashes_st {
unsigned long hash;
int suffix;
} BY_DIR_HASH;
typedef struct lookup_dir_entry_st {
char *dir;
int dir_type;
STACK_OF(BY_DIR_HASH) *hashes;
} BY_DIR_ENTRY;
typedef struct lookup_dir_st {
BUF_MEM *buffer;
STACK_OF(BY_DIR_ENTRY) *dirs;
} BY_DIR;
DECLARE_STACK_OF(BY_DIR_HASH)
DECLARE_STACK_OF(BY_DIR_ENTRY)
static int dir_ctrl(X509_LOOKUP *ctx, int cmd, const char *argp, long argl,
char **ret);
static int new_dir(X509_LOOKUP *lu);
static void free_dir(X509_LOOKUP *lu);
static int add_cert_dir(BY_DIR *ctx, const char *dir, int type);
static int get_cert_by_subject(X509_LOOKUP *xl, int type, X509_NAME *name,
X509_OBJECT *ret);
static X509_LOOKUP_METHOD x509_dir_lookup = {
"Load certs from files in a directory",
new_dir, /* new */
free_dir, /* free */
NULL, /* init */
NULL, /* shutdown */
dir_ctrl, /* ctrl */
get_cert_by_subject, /* get_by_subject */
NULL, /* get_by_issuer_serial */
NULL, /* get_by_fingerprint */
NULL, /* get_by_alias */
};
X509_LOOKUP_METHOD *X509_LOOKUP_hash_dir(void)
{
return (&x509_dir_lookup);
}
static int dir_ctrl(X509_LOOKUP *ctx, int cmd, const char *argp, long argl,
char **retp)
{
int ret = 0;
BY_DIR *ld;
char *dir = NULL;
ld = (BY_DIR *)ctx->method_data;
switch (cmd) {
case X509_L_ADD_DIR:
if (argl == X509_FILETYPE_DEFAULT) {
dir = (char *)getenv(X509_get_default_cert_dir_env());
if (dir)
ret = add_cert_dir(ld, dir, X509_FILETYPE_PEM);
else
ret = add_cert_dir(ld, X509_get_default_cert_dir(),
X509_FILETYPE_PEM);
if (!ret) {
OPENSSL_PUT_ERROR(X509, X509_R_LOADING_CERT_DIR);
}
} else
ret = add_cert_dir(ld, argp, (int)argl);
break;
}
return (ret);
}
static int new_dir(X509_LOOKUP *lu)
{
BY_DIR *a;
if ((a = (BY_DIR *)OPENSSL_malloc(sizeof(BY_DIR))) == NULL)
return (0);
if ((a->buffer = BUF_MEM_new()) == NULL) {
OPENSSL_free(a);
return (0);
}
a->dirs = NULL;
lu->method_data = (char *)a;
return (1);
}
static void by_dir_hash_free(BY_DIR_HASH *hash)
{
OPENSSL_free(hash);
}
static int by_dir_hash_cmp(const BY_DIR_HASH **a, const BY_DIR_HASH **b)
{
if ((*a)->hash > (*b)->hash)
return 1;
if ((*a)->hash < (*b)->hash)
return -1;
return 0;
}
static void by_dir_entry_free(BY_DIR_ENTRY *ent)
{
if (ent->dir)
OPENSSL_free(ent->dir);
if (ent->hashes)
sk_BY_DIR_HASH_pop_free(ent->hashes, by_dir_hash_free);
OPENSSL_free(ent);
}
static void free_dir(X509_LOOKUP *lu)
{
BY_DIR *a;
a = (BY_DIR *)lu->method_data;
if (a->dirs != NULL)
sk_BY_DIR_ENTRY_pop_free(a->dirs, by_dir_entry_free);
if (a->buffer != NULL)
BUF_MEM_free(a->buffer);
OPENSSL_free(a);
}
static int add_cert_dir(BY_DIR *ctx, const char *dir, int type)
{
size_t j, len;
const char *s, *ss, *p;
if (dir == NULL || !*dir) {
OPENSSL_PUT_ERROR(X509, X509_R_INVALID_DIRECTORY);
return 0;
}
s = dir;
p = s;
do {
if ((*p == ':') || (*p == '\0')) {
BY_DIR_ENTRY *ent;
ss = s;
s = p + 1;
len = p - ss;
if (len == 0)
continue;
for (j = 0; j < sk_BY_DIR_ENTRY_num(ctx->dirs); j++) {
ent = sk_BY_DIR_ENTRY_value(ctx->dirs, j);
if (strlen(ent->dir) == len &&
strncmp(ent->dir, ss, len) == 0)
break;
}
if (j < sk_BY_DIR_ENTRY_num(ctx->dirs))
continue;
if (ctx->dirs == NULL) {
ctx->dirs = sk_BY_DIR_ENTRY_new_null();
if (!ctx->dirs) {
OPENSSL_PUT_ERROR(X509, ERR_R_MALLOC_FAILURE);
return 0;
}
}
ent = OPENSSL_malloc(sizeof(BY_DIR_ENTRY));
if (!ent)
return 0;
ent->dir_type = type;
ent->hashes = sk_BY_DIR_HASH_new(by_dir_hash_cmp);
ent->dir = OPENSSL_malloc(len + 1);
if (!ent->dir || !ent->hashes) {
by_dir_entry_free(ent);
return 0;
}
strncpy(ent->dir, ss, len);
ent->dir[len] = '\0';
if (!sk_BY_DIR_ENTRY_push(ctx->dirs, ent)) {
by_dir_entry_free(ent);
return 0;
}
}
} while (*p++ != '\0');
return 1;
}
/*
* g_ent_hashes_lock protects the |hashes| member of all |BY_DIR_ENTRY|
* objects.
*/
static struct CRYPTO_STATIC_MUTEX g_ent_hashes_lock =
CRYPTO_STATIC_MUTEX_INIT;
static int get_cert_by_subject(X509_LOOKUP *xl, int type, X509_NAME *name,
X509_OBJECT *ret)
{
BY_DIR *ctx;
union {
struct {
X509 st_x509;
X509_CINF st_x509_cinf;
} x509;
struct {
X509_CRL st_crl;
X509_CRL_INFO st_crl_info;
} crl;
} data;
int ok = 0;
size_t i;
int j, k;
unsigned long h;
unsigned long hash_array[2];
int hash_index;
BUF_MEM *b = NULL;
X509_OBJECT stmp, *tmp;
const char *postfix = "";
if (name == NULL)
return (0);
stmp.type = type;
if (type == X509_LU_X509) {
data.x509.st_x509.cert_info = &data.x509.st_x509_cinf;
data.x509.st_x509_cinf.subject = name;
stmp.data.x509 = &data.x509.st_x509;
postfix = "";
} else if (type == X509_LU_CRL) {
data.crl.st_crl.crl = &data.crl.st_crl_info;
data.crl.st_crl_info.issuer = name;
stmp.data.crl = &data.crl.st_crl;
postfix = "r";
} else {
OPENSSL_PUT_ERROR(X509, X509_R_WRONG_LOOKUP_TYPE);
goto finish;
}
if ((b = BUF_MEM_new()) == NULL) {
OPENSSL_PUT_ERROR(X509, ERR_R_BUF_LIB);
goto finish;
}
ctx = (BY_DIR *)xl->method_data;
hash_array[0] = X509_NAME_hash(name);
hash_array[1] = X509_NAME_hash_old(name);
for (hash_index = 0; hash_index < 2; ++hash_index) {
h = hash_array[hash_index];
for (i = 0; i < sk_BY_DIR_ENTRY_num(ctx->dirs); i++) {
BY_DIR_ENTRY *ent;
size_t idx;
BY_DIR_HASH htmp, *hent;
ent = sk_BY_DIR_ENTRY_value(ctx->dirs, i);
j = strlen(ent->dir) + 1 + 8 + 6 + 1 + 1;
if (!BUF_MEM_grow(b, j)) {
OPENSSL_PUT_ERROR(X509, ERR_R_MALLOC_FAILURE);
goto finish;
}
if (type == X509_LU_CRL && ent->hashes) {
htmp.hash = h;
CRYPTO_STATIC_MUTEX_lock_read(&g_ent_hashes_lock);
if (sk_BY_DIR_HASH_find(ent->hashes, &idx, &htmp)) {
hent = sk_BY_DIR_HASH_value(ent->hashes, idx);
k = hent->suffix;
} else {
hent = NULL;
k = 0;
}
CRYPTO_STATIC_MUTEX_unlock_read(&g_ent_hashes_lock);
} else {
k = 0;
hent = NULL;
}
for (;;) {
char c = '/';
#ifdef OPENSSL_SYS_VMS
c = ent->dir[strlen(ent->dir) - 1];
if (c != ':' && c != '>' && c != ']') {
/*
* If no separator is present, we assume the directory
* specifier is a logical name, and add a colon. We
* really should use better VMS routines for merging
* things like this, but this will do for now... --
* Richard Levitte
*/
c = ':';
} else {
c = '\0';
}
#endif
if (c == '\0') {
/*
* This is special. When c == '\0', no directory
* separator should be added.
*/
BIO_snprintf(b->data, b->max,
"%s%08lx.%s%d", ent->dir, h, postfix, k);
} else {
BIO_snprintf(b->data, b->max,
"%s%c%08lx.%s%d", ent->dir, c, h,
postfix, k);
}
#ifndef OPENSSL_NO_POSIX_IO
# if defined(_WIN32) && !defined(stat)
# define stat _stat
# endif
{
struct stat st;
if (stat(b->data, &st) < 0)
break;
}
#endif
/* found one. */
if (type == X509_LU_X509) {
if ((X509_load_cert_file(xl, b->data,
ent->dir_type)) == 0)
break;
} else if (type == X509_LU_CRL) {
if ((X509_load_crl_file(xl, b->data, ent->dir_type)) == 0)
break;
}
/* else case will caught higher up */
k++;
}
/*
* we have added it to the cache so now pull it out again
*/
CRYPTO_MUTEX_lock_write(&xl->store_ctx->objs_lock);
tmp = NULL;
if (sk_X509_OBJECT_find(xl->store_ctx->objs, &idx, &stmp)) {
tmp = sk_X509_OBJECT_value(xl->store_ctx->objs, idx);
}
CRYPTO_MUTEX_unlock_write(&xl->store_ctx->objs_lock);
/*
* If a CRL, update the last file suffix added for this
*/
if (type == X509_LU_CRL) {
CRYPTO_STATIC_MUTEX_lock_write(&g_ent_hashes_lock);
/*
* Look for entry again in case another thread added an entry
* first.
*/
if (!hent) {
htmp.hash = h;
if (sk_BY_DIR_HASH_find(ent->hashes, &idx, &htmp))
hent = sk_BY_DIR_HASH_value(ent->hashes, idx);
}
if (!hent) {
hent = OPENSSL_malloc(sizeof(BY_DIR_HASH));
if (hent == NULL) {
CRYPTO_STATIC_MUTEX_unlock_write(&g_ent_hashes_lock);
ok = 0;
goto finish;
}
hent->hash = h;
hent->suffix = k;
if (!sk_BY_DIR_HASH_push(ent->hashes, hent)) {
CRYPTO_STATIC_MUTEX_unlock_write(&g_ent_hashes_lock);
OPENSSL_free(hent);
ok = 0;
goto finish;
}
} else if (hent->suffix < k)
hent->suffix = k;
CRYPTO_STATIC_MUTEX_unlock_write(&g_ent_hashes_lock);
}
if (tmp != NULL) {
ok = 1;
ret->type = tmp->type;
OPENSSL_memcpy(&ret->data, &tmp->data, sizeof(ret->data));
/*
* If we were going to up the reference count, we would need
* to do it on a perl 'type' basis
*/
/*
* CRYPTO_add(&tmp->data.x509->references,1,
* CRYPTO_LOCK_X509);
*/
goto finish;
}
}
}
finish:
if (b != NULL)
BUF_MEM_free(b);
return (ok);
}