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snmp_openssl.c
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snmp_openssl.c
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/*
* snmp_openssl.c
*
* Portions of this file are subject to the following copyright(s). See
* the Net-SNMP's COPYING file for more details and other copyrights
* that may apply:
*
* Portions of this file are copyrighted by:
* Copyright (c) 2016 VMware, Inc. All rights reserved.
* Use is subject to license terms specified in the COPYING file
* distributed with the Net-SNMP package.
*/
#include <net-snmp/net-snmp-config.h>
#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/net-snmp-features.h>
/** OpenSSL compat functions for apps */
#if defined(NETSNMP_USE_OPENSSL)
#include <string.h>
#include <openssl/dh.h>
#ifndef HAVE_DH_GET0_PQG
void
DH_get0_pqg(const DH *dh, const BIGNUM **p, const BIGNUM **q, const BIGNUM **g)
{
if (p != NULL)
*p = dh->p;
if (q != NULL)
*q = dh->q;
if (g != NULL)
*g = dh->g;
}
#endif
#ifndef HAVE_DH_GET0_KEY
void
DH_get0_key(const DH *dh, const BIGNUM **pub_key, const BIGNUM **priv_key)
{
if (pub_key != NULL)
*pub_key = dh->pub_key;
if (priv_key != NULL)
*priv_key = dh->priv_key;
}
#endif
#ifndef HAVE_DH_SET0_PQG
int
DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g)
{
/* If the fields p and g in d are NULL, the corresponding input
* parameters MUST be non-NULL. q may remain NULL.
*/
if ((dh->p == NULL && p == NULL)
|| (dh->g == NULL && g == NULL))
return 0;
if (p != NULL) {
BN_free(dh->p);
dh->p = p;
}
if (q != NULL) {
BN_free(dh->q);
dh->q = q;
}
if (g != NULL) {
BN_free(dh->g);
dh->g = g;
}
if (q != NULL) {
dh->length = BN_num_bits(q);
}
return 1;
}
#endif
#endif /* defined(NETSNMP_USE_OPENSSL) */
/** TLS/DTLS certificatte support */
#if defined(NETSNMP_USE_OPENSSL) && defined(HAVE_LIBSSL) && !defined(NETSNMP_FEATURE_REMOVE_CERT_UTIL)
netsnmp_feature_require(container_free_all)
netsnmp_feature_child_of(openssl_cert_get_subjectAltNames, netsnmp_unused)
netsnmp_feature_child_of(openssl_ht2nid, netsnmp_unused)
netsnmp_feature_child_of(openssl_err_log, netsnmp_unused)
netsnmp_feature_child_of(cert_dump_names, netsnmp_unused)
#include <ctype.h>
#include <openssl/evp.h>
#include <openssl/ssl.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include <openssl/err.h>
#include <openssl/objects.h>
#include <net-snmp/library/snmp_debug.h>
#include <net-snmp/library/cert_util.h>
#include <net-snmp/library/snmp_openssl.h>
static u_char have_started_already = 0;
/*
* This code merely does openssl initialization so that multilpe
* modules are safe to call netsnmp_init_openssl() for bootstrapping
* without worrying about other callers that may have already done so.
*/
void netsnmp_init_openssl(void) {
/* avoid duplicate calls */
if (have_started_already)
return;
have_started_already = 1;
DEBUGMSGTL(("snmp_openssl", "initializing\n"));
/* Initializing OpenSSL */
#ifdef HAVE_SSL_LIBRARY_INIT
SSL_library_init();
#endif
#ifdef HAVE_SSL_LOAD_ERROR_STRINGS
SSL_load_error_strings();
#endif
ERR_load_BIO_strings();
OpenSSL_add_all_algorithms();
}
/** netsnmp_openssl_cert_get_name: get subject name field from cert
* @internal
*/
/** instead of exposing this function, make helper functions for each
* field, like netsnmp_openssl_cert_get_commonName, below */
static char *
_cert_get_name(X509 *ocert, int which, char **buf, int *len, int flags)
{
X509_NAME *osubj_name;
int space;
char *buf_ptr;
if ((NULL == ocert) || ((buf && !len) || (len && !buf)))
return NULL;
osubj_name = X509_get_subject_name(ocert);
if (NULL == osubj_name) {
DEBUGMSGT(("openssl:cert:name", "no subject name!\n"));
return NULL;
}
/** see if buf is big enough, or allocate buf if none specified */
space = X509_NAME_get_text_by_NID(osubj_name, which, NULL, 0);
if (-1 == space)
return NULL;
++space; /* for NUL */
if (buf && *buf) {
if (*len < space)
return NULL;
buf_ptr = *buf;
}
else {
buf_ptr = calloc(1,space);
if (!buf_ptr)
return NULL;
}
space = X509_NAME_get_text_by_NID(osubj_name, which, buf_ptr, space);
if (len)
*len = space;
return buf_ptr;
}
/** netsnmp_openssl_cert_get_subjectName: get subject name field from cert
*/
char *
netsnmp_openssl_cert_get_subjectName(X509 *ocert, char **buf, int *len)
{
X509_NAME *osubj_name;
int space;
char *buf_ptr;
if ((NULL == ocert) || ((buf && !len) || (len && !buf)))
return NULL;
osubj_name = X509_get_subject_name(ocert);
if (NULL == osubj_name) {
DEBUGMSGT(("openssl:cert:name", "no subject name!\n"));
return NULL;
}
if (buf) {
buf_ptr = *buf;
space = *len;
}
else {
buf_ptr = NULL;
space = 0;
}
buf_ptr = X509_NAME_oneline(osubj_name, buf_ptr, space);
if (len)
*len = strlen(buf_ptr);
return buf_ptr;
}
/** netsnmp_openssl_cert_get_commonName: get commonName for cert.
* if a pointer to a buffer and its length are specified, they will be
* used. otherwise, a new buffer will be allocated, which the caller will
* be responsbile for releasing.
*/
char *
netsnmp_openssl_cert_get_commonName(X509 *ocert, char **buf, int *len)
{
return _cert_get_name(ocert, NID_commonName, buf, len, 0);
}
#ifndef NETSNMP_FEATURE_REMOVE_CERT_DUMP_NAMES
/** netsnmp_openssl_cert_dump_name: dump subject names in cert
*/
void
netsnmp_openssl_cert_dump_names(X509 *ocert)
{
int i, onid;
X509_NAME_ENTRY *oname_entry;
ASN1_STRING *oname_value;
X509_NAME *osubj_name;
const char *prefix_short, *prefix_long;
if (NULL == ocert)
return;
osubj_name = X509_get_subject_name(ocert);
if (NULL == osubj_name) {
DEBUGMSGT(("9:cert:dump:names", "no subject name!\n"));
return;
}
for (i = 0; i < X509_NAME_entry_count(osubj_name); i++) {
oname_entry = X509_NAME_get_entry(osubj_name, i);
netsnmp_assert(NULL != oname_entry);
oname_value = X509_NAME_ENTRY_get_data(oname_entry);
if (oname_value->type != V_ASN1_PRINTABLESTRING)
continue;
/** get NID */
onid = OBJ_obj2nid(X509_NAME_ENTRY_get_object(oname_entry));
if (onid == NID_undef) {
prefix_long = prefix_short = "UNKNOWN";
}
else {
prefix_long = OBJ_nid2ln(onid);
prefix_short = OBJ_nid2sn(onid);
}
DEBUGMSGT(("9:cert:dump:names",
"[%02d] NID type %d, ASN type %d\n", i, onid,
oname_value->type));
DEBUGMSGT(("9:cert:dump:names", "%s/%s: '%s'\n", prefix_long,
prefix_short, ASN1_STRING_get0_data(oname_value)));
}
}
#endif /* NETSNMP_FEATURE_REMOVE_CERT_DUMP_NAMES */
static char *
_cert_get_extension(X509_EXTENSION *oext, char **buf, int *len, int flags)
{
int space;
char *buf_ptr = NULL;
u_char *data;
BIO *bio;
if ((NULL == oext) || ((buf && !len) || (len && !buf)))
return NULL;
bio = BIO_new(BIO_s_mem());
if (NULL == bio) {
snmp_log(LOG_ERR, "could not get bio for extension\n");
return NULL;
}
if (X509V3_EXT_print(bio, oext, 0, 0) != 1) {
snmp_log(LOG_ERR, "could not print extension!\n");
BIO_vfree(bio);
return NULL;
}
space = BIO_get_mem_data(bio, &data);
if (buf && *buf) {
if (*len < space)
buf_ptr = NULL;
else
buf_ptr = *buf;
}
else
buf_ptr = calloc(1,space + 1);
if (!buf_ptr) {
snmp_log(LOG_ERR,
"not enough space or error in allocation for extenstion\n");
BIO_vfree(bio);
return NULL;
}
memcpy(buf_ptr, data, space);
buf_ptr[space] = 0;
if (len)
*len = space;
BIO_vfree(bio);
return buf_ptr;
}
/** netsnmp_openssl_cert_get_extension: get extension field from cert
* @internal
*/
/** instead of exposing this function, make helper functions for each
* field, like netsnmp_openssl_cert_get_subjectAltName, below */
X509_EXTENSION *
_cert_get_extension_at(X509 *ocert, int pos, char **buf, int *len, int flags)
{
X509_EXTENSION *oext;
if ((NULL == ocert) || ((buf && !len) || (len && !buf)))
return NULL;
oext = X509_get_ext(ocert,pos);
if (NULL == oext) {
snmp_log(LOG_ERR, "extension number %d not found!\n", pos);
netsnmp_openssl_cert_dump_extensions(ocert);
return NULL;
}
return oext;
}
/** netsnmp_openssl_cert_get_extension: get extension field from cert
* @internal
*/
/** instead of exposing this function, make helper functions for each
* field, like netsnmp_openssl_cert_get_subjectAltName, below */
static char *
_cert_get_extension_str_at(X509 *ocert, int pos, char **buf, int *len,
int flags)
{
X509_EXTENSION *oext;
if ((NULL == ocert) || ((buf && !len) || (len && !buf)))
return NULL;
oext = X509_get_ext(ocert,pos);
if (NULL == oext) {
snmp_log(LOG_ERR, "extension number %d not found!\n", pos);
netsnmp_openssl_cert_dump_extensions(ocert);
return NULL;
}
return _cert_get_extension(oext, buf, len, flags);
}
/** _cert_get_extension_id: get extension field from cert
* @internal
*/
/** instead of exposing this function, make helper functions for each
* field, like netsnmp_openssl_cert_get_subjectAltName, below */
X509_EXTENSION *
_cert_get_extension_id(X509 *ocert, int which, char **buf, int *len, int flags)
{
int pos;
if ((NULL == ocert) || ((buf && !len) || (len && !buf)))
return NULL;
pos = X509_get_ext_by_NID(ocert,which,-1);
if (pos < 0) {
DEBUGMSGT(("openssl:cert:name", "no extension %d\n", which));
return NULL;
}
return _cert_get_extension_at(ocert, pos, buf, len, flags);
}
#ifndef NETSNMP_FEATURE_REMOVE_OPENSSL_CERT_GET_SUBJECTALTNAMES
/** _cert_get_extension_id_str: get extension field from cert
* @internal
*/
/** instead of exposing this function, make helper functions for each
* field, like netsnmp_openssl_cert_get_subjectAltName, below */
static char *
_cert_get_extension_id_str(X509 *ocert, int which, char **buf, int *len,
int flags)
{
int pos;
if ((NULL == ocert) || ((buf && !len) || (len && !buf)))
return NULL;
pos = X509_get_ext_by_NID(ocert,which,-1);
if (pos < 0) {
DEBUGMSGT(("openssl:cert:name", "no extension %d\n", which));
return NULL;
}
return _cert_get_extension_str_at(ocert, pos, buf, len, flags);
}
#endif /* NETSNMP_FEATURE_REMOVE_OPENSSL_CERT_GET_SUBJECTALTNAMES */
static char *
_extract_oname(const GENERAL_NAME *oname)
{
char ipbuf[60], *buf = NULL, *rtn = NULL;
if (NULL == oname)
return NULL;
switch ( oname->type ) {
case GEN_EMAIL:
case GEN_DNS:
/*case GEN_URI:*/
ASN1_STRING_to_UTF8((unsigned char**)&buf, oname->d.ia5);
if (buf)
rtn = strdup(buf);
break;
case GEN_IPADD:
if (oname->d.iPAddress->length == 4) {
sprintf(ipbuf, "%d.%d.%d.%d", oname->d.iPAddress->data[0],
oname->d.iPAddress->data[1],
oname->d.iPAddress->data[2],
oname->d.iPAddress->data[3]);
rtn = strdup(ipbuf);
}
else if ((oname->d.iPAddress->length == 16) ||
(oname->d.iPAddress->length == 20)) {
char *pos = ipbuf;
int j;
for(j = 0; j < oname->d.iPAddress->length; ++j) {
*pos++ = VAL2HEX(oname->d.iPAddress->data[j]);
*pos++ = ':';
}
*pos = '\0';
rtn = strdup(ipbuf);
}
else
NETSNMP_LOGONCE((LOG_WARNING, "unexpected ip addr length %d\n",
oname->d.iPAddress->length));
break;
default:
DEBUGMSGT(("openssl:cert:san", "unknown/unsupported type %d\n",
oname->type));
break;
}
DEBUGMSGT(("9:openssl:cert:san", "san=%s\n", buf));
if (buf)
OPENSSL_free(buf);
return rtn;
}
#ifndef NETSNMP_FEATURE_REMOVE_OPENSSL_CERT_GET_SUBJECTALTNAMES
/** netsnmp_openssl_cert_get_subjectAltName: get subjectAltName for cert.
* if a pointer to a buffer and its length are specified, they will be
* used. otherwise, a new buffer will be allocated, which the caller will
* be responsbile for releasing.
*/
char *
netsnmp_openssl_cert_get_subjectAltNames(X509 *ocert, char **buf, int *len)
{
return _cert_get_extension_id_str(ocert, NID_subject_alt_name, buf, len, 0);
}
#endif /* NETSNMP_FEATURE_REMOVE_OPENSSL_CERT_GET_SUBJECTALTNAMES */
void
netsnmp_openssl_cert_dump_extensions(X509 *ocert)
{
X509_EXTENSION *extension;
const char *extension_name;
char buf[SNMP_MAXBUF_SMALL], *buf_ptr = buf, *str, *lf;
int i, num_extensions, buf_len, nid;
if (NULL == ocert)
return;
DEBUGIF("9:cert:dump")
;
else
return; /* bail if debug not enabled */
num_extensions = X509_get_ext_count(ocert);
if (0 == num_extensions)
DEBUGMSGT(("9:cert:dump", " 0 extensions\n"));
for(i = 0; i < num_extensions; i++) {
extension = X509_get_ext(ocert, i);
nid = OBJ_obj2nid(X509_EXTENSION_get_object(extension));
extension_name = OBJ_nid2sn(nid);
buf_len = sizeof(buf);
str = _cert_get_extension_str_at(ocert, i, &buf_ptr, &buf_len, 0);
lf = strchr(str, '\n'); /* look for multiline strings */
if (NULL != lf)
*lf = '\0'; /* only log first line of multiline here */
DEBUGMSGT(("9:cert:dump", " %2d: %s = %s\n", i,
extension_name, str));
while(lf) { /* log remaining parts of multiline string */
str = ++lf;
if (*str == '\0')
break;
lf = strchr(str, '\n');
if (NULL == lf)
break;
*lf = '\0';
DEBUGMSGT(("9:cert:dump", " %s\n", str));
}
}
}
static int _htmap[NS_HASH_MAX + 1] = {
0, NID_md5WithRSAEncryption, NID_sha1WithRSAEncryption,
NID_sha224WithRSAEncryption, NID_sha256WithRSAEncryption,
NID_sha384WithRSAEncryption, NID_sha512WithRSAEncryption };
int
_nid2ht(int nid)
{
int i;
for (i=1; i<= NS_HASH_MAX; ++i) {
if (nid == _htmap[i])
return i;
}
return 0;
}
#ifndef NETSNMP_FEATURE_REMOVE_OPENSSL_HT2NID
int
_ht2nid(int ht)
{
if ((ht < 0) || (ht > NS_HASH_MAX))
return 0;
return _htmap[ht];
}
#endif /* NETSNMP_FEATURE_REMOVE_OPENSSL_HT2NID */
/**
* returns allocated pointer caller must free.
*/
int
netsnmp_openssl_cert_get_hash_type(X509 *ocert)
{
if (NULL == ocert)
return 0;
return _nid2ht(X509_get_signature_nid(ocert));
}
/**
* returns allocated pointer caller must free.
*/
char *
netsnmp_openssl_cert_get_fingerprint(X509 *ocert, int alg)
{
u_char fingerprint[EVP_MAX_MD_SIZE];
u_int fingerprint_len, nid;
const EVP_MD *digest;
char *result = NULL;
if (NULL == ocert)
return NULL;
nid = X509_get_signature_nid(ocert);
DEBUGMSGT(("9:openssl:fingerprint", "alg %d, cert nid %d (%d)\n", alg, nid,
_nid2ht(nid)));
if ((-1 == alg) && nid)
alg = _nid2ht(nid);
switch (alg) {
case NS_HASH_MD5:
snmp_log(LOG_ERR, "hash type md5 not yet supported\n");
return NULL;
break;
case NS_HASH_NONE:
snmp_log(LOG_ERR, "hash type none not supported. using SHA1\n");
/* FALLTHROUGH */
case NS_HASH_SHA1:
digest = EVP_sha1();
break;
#ifdef HAVE_EVP_SHA224
case NS_HASH_SHA224:
digest = EVP_sha224();
break;
case NS_HASH_SHA256:
digest = EVP_sha256();
break;
#endif
#ifdef HAVE_EVP_SHA384
case NS_HASH_SHA384:
digest = EVP_sha384();
break;
case NS_HASH_SHA512:
digest = EVP_sha512();
break;
#endif
default:
snmp_log(LOG_ERR, "unknown hash algorithm %d\n", alg);
return NULL;
}
if (_nid2ht(nid) != alg) {
DEBUGMSGT(("openssl:fingerprint",
"WARNING: alg %d does not match cert alg %d\n",
alg, _nid2ht(nid)));
}
if (X509_digest(ocert,digest,fingerprint,&fingerprint_len)) {
binary_to_hex(fingerprint, fingerprint_len, &result);
if (NULL == result)
snmp_log(LOG_ERR, "failed to hexify fingerprint\n");
else
DEBUGMSGT(("9:openssl:fingerprint", "fingerprint %s\n", result));
}
else
snmp_log(LOG_ERR,"failed to compute fingerprint\n");
return result;
}
/**
* get container of netsnmp_cert_map structures from an ssl connection
* certificate chain.
*/
netsnmp_container *
netsnmp_openssl_get_cert_chain(SSL *ssl)
{
X509 *ocert, *ocert_tmp;
STACK_OF(X509) *ochain;
char *fingerprint;
netsnmp_container *chain_map;
netsnmp_cert_map *cert_map;
int i;
netsnmp_assert_or_return(ssl != NULL, NULL);
if (NULL == (ocert = SSL_get_peer_certificate(ssl))) {
/** no peer cert */
snmp_log(LOG_ERR, "SSL peer has no certificate\n");
return NULL;
}
DEBUGIF("9:cert:dump") {
netsnmp_openssl_cert_dump_extensions(ocert);
}
/*
* get fingerprint and save it
*/
fingerprint = netsnmp_openssl_cert_get_fingerprint(ocert, -1);
if (NULL == fingerprint)
return NULL;
/*
* allocate cert map. Don't pass in fingerprint, since it would strdup
* it and we've already got a copy.
*/
cert_map = netsnmp_cert_map_alloc(NULL, ocert);
if (NULL == cert_map) {
free(fingerprint);
return NULL;
}
cert_map->fingerprint = fingerprint;
cert_map->hashType = netsnmp_openssl_cert_get_hash_type(ocert);
chain_map = netsnmp_cert_map_container_create(0); /* no fp subcontainer */
if (NULL == chain_map) {
netsnmp_cert_map_free(cert_map);
return NULL;
}
CONTAINER_INSERT(chain_map, cert_map);
/** check for a chain to a CA */
ochain = SSL_get_peer_cert_chain(ssl);
if ((NULL == ochain) || (0 == sk_num((const void *)ochain))) {
DEBUGMSGT(("ssl:cert:chain", "peer has no cert chain\n"));
}
else {
/*
* loop over chain, adding fingerprint / cert for each
*/
DEBUGMSGT(("ssl:cert:chain", "examining cert chain\n"));
for(i = 0; i < sk_num((const void *)ochain); ++i) {
ocert_tmp = (X509*)sk_value((const void *)ochain,i);
fingerprint = netsnmp_openssl_cert_get_fingerprint(ocert_tmp,
NS_HASH_SHA1);
if (NULL == fingerprint)
break;
cert_map = netsnmp_cert_map_alloc(NULL, ocert);
if (NULL == cert_map) {
free(fingerprint);
break;
}
cert_map->fingerprint = fingerprint;
cert_map->hashType = netsnmp_openssl_cert_get_hash_type(ocert_tmp);
CONTAINER_INSERT(chain_map, cert_map);
} /* chain loop */
/*
* if we broke out of loop before finishing, clean up
*/
if (i < sk_num((const void *)ochain))
CONTAINER_FREE_ALL(chain_map, NULL);
} /* got peer chain */
DEBUGMSGT(("ssl:cert:chain", "found %" NETSNMP_PRIz "u certs in chain\n",
CONTAINER_SIZE(chain_map)));
if (CONTAINER_SIZE(chain_map) == 0) {
CONTAINER_FREE(chain_map);
chain_map = NULL;
}
return chain_map;
}
/*
tlstmCertSANRFC822Name "Maps a subjectAltName's rfc822Name to a
tmSecurityName. The local part of the rfc822Name is
passed unaltered but the host-part of the name must
be passed in lower case.
Example rfc822Name Field: FooBar@Example.COM
is mapped to tmSecurityName: FooBar@example.com"
tlstmCertSANDNSName "Maps a subjectAltName's dNSName to a
tmSecurityName after first converting it to all
lower case."
tlstmCertSANIpAddress "Maps a subjectAltName's iPAddress to a
tmSecurityName by transforming the binary encoded
address as follows:
1) for IPv4 the value is converted into a decimal
dotted quad address (e.g. '192.0.2.1')
2) for IPv6 addresses the value is converted into a
32-character all lowercase hexadecimal string
without any colon separators.
Note that the resulting length is the maximum
length supported by the View-Based Access Control
Model (VACM). Note that using both the Transport
Security Model's support for transport prefixes
(see the SNMP-TSM-MIB's
snmpTsmConfigurationUsePrefix object for details)
will result in securityName lengths that exceed
what VACM can handle."
tlstmCertSANAny "Maps any of the following fields using the
corresponding mapping algorithms:
| rfc822Name | tlstmCertSANRFC822Name |
| dNSName | tlstmCertSANDNSName |
| iPAddress | tlstmCertSANIpAddress |
The first matching subjectAltName value found in the
certificate of the above types MUST be used when
deriving the tmSecurityName."
*/
char *
_cert_get_san_type(X509 *ocert, int mapType)
{
GENERAL_NAMES *onames;
const GENERAL_NAME *oname = NULL;
char *buf = NULL, *lower = NULL;
int count, i;
onames = (GENERAL_NAMES *)X509_get_ext_d2i(ocert, NID_subject_alt_name,
NULL, NULL );
if (NULL == onames)
return NULL;
count = sk_GENERAL_NAME_num(onames);
for (i=0 ; i <count; ++i) {
oname = sk_GENERAL_NAME_value(onames, i);
if (GEN_DNS == oname->type) {
if ((TSNM_tlstmCertSANDNSName == mapType) ||
(TSNM_tlstmCertSANAny == mapType)) {
lower = buf = _extract_oname( oname );
break;
}
}
else if (GEN_IPADD == oname->type) {
if ((TSNM_tlstmCertSANIpAddress == mapType) ||
(TSNM_tlstmCertSANAny == mapType)) {
buf = _extract_oname(oname);
break;
}
}
else if (GEN_EMAIL == oname->type) {
if ((TSNM_tlstmCertSANRFC822Name == mapType) ||
(TSNM_tlstmCertSANAny == mapType)) {
buf = _extract_oname(oname);
lower = strchr(buf, '@');
if (NULL == lower) {
DEBUGMSGT(("openssl:secname:extract",
"email %s has no '@'!\n", buf));
}
else {
++lower;
break;
}
}
}
} /* for loop */
if (lower)
for ( ; *lower; ++lower )
if (isascii(*lower))
*lower = tolower(0xFF & *lower);
DEBUGMSGT(("openssl:cert:extension:san", "#%d type %d: %s\n", i,
oname ? oname->type : -1, buf ? buf : "NULL"));
return buf;
}
char *
netsnmp_openssl_extract_secname(netsnmp_cert_map *cert_map,
netsnmp_cert_map *peer_cert)
{
char *rtn = NULL;
if (NULL == cert_map)
return NULL;
DEBUGMSGT(("openssl:secname:extract",
"checking priority %d, san of type %d for %s\n",
cert_map->priority, cert_map->mapType, peer_cert->fingerprint));
switch(cert_map->mapType) {
case TSNM_tlstmCertSpecified:
rtn = strdup(cert_map->data);
break;
case TSNM_tlstmCertSANRFC822Name:
case TSNM_tlstmCertSANDNSName:
case TSNM_tlstmCertSANIpAddress:
case TSNM_tlstmCertSANAny:
if (NULL == peer_cert) {
DEBUGMSGT(("openssl:secname:extract", "no peer cert for %s\n",
cert_map->fingerprint));
break;
}
rtn = _cert_get_san_type(peer_cert->ocert, cert_map->mapType);
if (NULL == rtn) {
DEBUGMSGT(("openssl:secname:extract", "no san for %s\n",
peer_cert->fingerprint));
}
break;
case TSNM_tlstmCertCommonName:
rtn = netsnmp_openssl_cert_get_commonName(cert_map->ocert, NULL,
NULL);
break;
default:
snmp_log(LOG_ERR, "cant extract secname for unknown map type %d\n",
cert_map->mapType);
break;
} /* switch mapType */
if (rtn) {
DEBUGMSGT(("openssl:secname:extract",
"found map %d, type %d for %s: %s\n", cert_map->priority,
cert_map->mapType, peer_cert->fingerprint, rtn));
if (strlen(rtn) >32) {
DEBUGMSGT(("openssl:secname:extract",
"secName longer than 32 chars! dropping...\n"));
SNMP_FREE(rtn);
}
}
else
DEBUGMSGT(("openssl:secname:extract",
"no map of type %d for %s\n",
cert_map->mapType, peer_cert->fingerprint));
return rtn;
}
int
netsnmp_openssl_cert_issued_by(X509 *issuer, X509 *cert)
{
return (X509_check_issued(issuer, cert) == X509_V_OK);
}
#ifndef NETSNMP_FEATURE_REMOVE_OPENSSL_ERR_LOG
void
netsnmp_openssl_err_log(const char *prefix)
{
unsigned long err;
for (err = ERR_get_error(); err; err = ERR_get_error()) {
snmp_log(LOG_ERR,"%s: %ld\n", prefix ? prefix: "openssl error", err);
snmp_log(LOG_ERR, "library=%d, function=%d, reason=%d\n",
ERR_GET_LIB(err), ERR_GET_FUNC(err), ERR_GET_REASON(err));
}
}
#endif /* NETSNMP_FEATURE_REMOVE_OPENSSL_ERR_LOG */
void
netsnmp_openssl_null_checks(SSL *ssl, int *null_auth, int *null_cipher)
{
const SSL_CIPHER *cipher;
char tmp_buf[128], *cipher_alg, *auth_alg;
if (null_auth)
*null_auth = -1; /* unknown */
if (null_cipher)
*null_cipher = -1; /* unknown */
if (NULL == ssl)
return;
cipher = SSL_get_current_cipher(ssl);
if (NULL == cipher) {
DEBUGMSGTL(("ssl:cipher", "no cipher yet\n"));
return;
}
SSL_CIPHER_description(NETSNMP_REMOVE_CONST(SSL_CIPHER *, cipher), tmp_buf, sizeof(tmp_buf));
/** no \n since tmp_buf already has one */
DEBUGMSGTL(("ssl:cipher", "current cipher: %s", tmp_buf));
/*
* run "openssl ciphers -v eNULL" and "openssl ciphers -v aNULL"
* to see NULL encryption/authentication algorithms. e.g.
*
* EXP-ADH-RC4-MD5 SSLv3 Kx=DH(512) Au=None Enc=RC4(40) Mac=MD5 export
* NULL-SHA SSLv3 Kx=RSA Au=RSA Enc=None Mac=SHA1
*/
if (null_cipher) {
cipher_alg = strstr(tmp_buf, "Enc=");
if (cipher_alg) {
cipher_alg += 4;
if (strncmp(cipher_alg,"None", 4) == 0)
*null_cipher = 1;
else
*null_cipher = 0;
}
}
if (null_auth) {
auth_alg = strstr(tmp_buf, "Au=");
if (auth_alg) {
auth_alg += 3;
if (strncmp(auth_alg,"None", 4) == 0)
*null_auth = 1;
else
*null_auth = 0;
}
}
}
#ifndef HAVE_X509_GET_SIGNATURE_NID
int X509_get_signature_nid(const X509 *x)
{
return OBJ_obj2nid(x->sig_alg->algorithm);
}
#endif
#ifndef HAVE_ASN1_STRING_GET0_DATA
const unsigned char *ASN1_STRING_get0_data(const ASN1_STRING *x)
{
return x->data;
}
#endif
#ifndef HAVE_X509_NAME_ENTRY_GET_OBJECT
ASN1_OBJECT *X509_NAME_ENTRY_get_object(const X509_NAME_ENTRY *ne)
{
if (ne == NULL)
return NULL;
return ne->object;
}
#endif
#ifndef HAVE_X509_NAME_ENTRY_GET_DATA
ASN1_STRING *X509_NAME_ENTRY_get_data(const X509_NAME_ENTRY *ne)
{
if (ne == NULL)
return NULL;
return ne->value;
}
#endif
#ifndef HAVE_TLS_METHOD
const SSL_METHOD *TLS_method(void)
{
return TLSv1_method();
}
#endif