sslinfo contrib module - information about current SSL certificate

Author: Victor Wagner <vitus@cryptocom.ru>
This commit is contained in:
Peter Eisentraut 2006-09-04 15:07:46 +00:00
parent c8041474ee
commit 6dc920de59
6 changed files with 505 additions and 3 deletions

View File

@ -1,4 +1,4 @@
# $PostgreSQL: pgsql/contrib/Makefile,v 1.66 2006/05/30 13:25:57 momjian Exp $
# $PostgreSQL: pgsql/contrib/Makefile,v 1.67 2006/09/04 15:07:46 petere Exp $
subdir = contrib
top_builddir = ..
@ -36,6 +36,10 @@ WANTED_DIRS = \
userlock \
vacuumlo
ifeq ($(with_openssl),yes)
WANTED_DIRS += sslinfo
endif
# Missing:
# adddepend \ (does not have a makefile)
# mSQL-interface \ (requires msql installed)

9
contrib/sslinfo/Makefile Normal file
View File

@ -0,0 +1,9 @@
subdir = contrib/sslinfo
top_builddir = ../..
include $(top_builddir)/src/Makefile.global
MODULES = sslinfo
DATA_built = sslinfo.sql
DOC = README.pgsslinfo
include ../contrib-global.mk

View File

@ -0,0 +1,121 @@
sslinfo - information about current SSL certificate for PostgreSQL
==================================================================
Copyright (c) 2006 Cryptocom LTD
Author: Victor Wagner <vitus@cryptocom.ru>
E-Mail of Cryptocom OpenSSL development group: <openssl@cryptocom.ru>
1. Notes
--------
This extension won't build unless your PostgreSQL server is configured
with --with-openssl. Information provided with these functions would
be completely useless if you don't use SSL to connect to database.
2. Functions Description
------------------------
2.1. ssl_is_used()
~~~~~~~~~~~~~~~~~~
ssl_is_used() RETURNS boolean;
Returns TRUE, if current connection to server uses SSL and FALSE
otherwise.
2.2. ssl_client_cert_present()
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ssl_client_cert_present() RETURNS boolean
Returns TRUE if current client have presented valid SSL client
certificate to the server and FALSE otherwise (e.g., no SSL,
certificate hadn't be requested by server).
2.3. ssl_client_serial()
~~~~~~~~~~~~~~~~~~~~~~~~
ssl_client_serial() RETURNS numeric
Returns serial number of current client certificate. The combination
of certificate serial number and certificate issuer is guaranteed to
uniquely identify certificate (but not its owner -- the owner ought to
regularily change his keys, and get new certificates from the issuer).
So, if you run you own CA and allow only certificates from this CA to
be accepted by server, the serial number is the most reliable (albeit
not very mnemonic) means to indentify user.
2.4. ssl_client_dn()
~~~~~~~~~~~~~~~~~~~~
ssl_client_dn() RETURNS text
Returns the full subject of current client certificate, converting
character data into the current database encoding. It is assumed that
if you use non-Latin characters in the certificate names, your
database is able to represent these characters, too. If your database
uses the SQL_ASCII encoding, non-Latin characters in the name will be
represented as UTF-8 sequences.
The result looks like '/CN=Somebody /C=Some country/O=Some organization'.
2.5. ssl_issuer_dn()
~~~~~~~~~~~~~~~~~~~~
Returns the full issuer name of the client certificate, converting
character data into current database encoding.
The combination of the return value of this function with the
certificate serial number uniquely identifies the certificate.
The result of this function is really useful only if you have more
than one trusted CA certificate in your server's root.crt file, or if
this CA has issued some intermediate certificate authority
certificates.
2.6. ssl_client_dn_field()
~~~~~~~~~~~~~~~~~~~~~~~~~~
ssl_client_dn_field(fieldName text) RETURNS text
This function returns the value of the specified field in the
certificate subject. Field names are string constants that are
converted into ASN1 object identificators using the OpenSSL object
database. The following values are acceptable:
commonName (alias CN)
surname (alias SN)
name
givenName (alias GN)
countryName (alias C)
localityName (alias L)
stateOrProvinceName (alias ST)
organizationName (alias O)
organizationUnitName (alias OU)
title
description
initials
postalCode
streetAddress
generationQualifier
description
dnQualifier
x500UniqueIdentifier
pseudonim
role
emailAddress
All of these fields are optional, except commonName. It depends
entirely on your CA policy which of them would be included and which
wouldn't. The meaning of these fields, howeer, is strictly defined by
the X.500 and X.509 standards, so you cannot just assign arbitrary
meaning to them.
2.7 ssl_issuer_field()
~~~~~~~~~~~~~~~~~~~
ssl_issuer_field(fieldName text) RETURNS text;
Does same as ssl_client_dn_field, but for the certificate issuer
rather than the certificate subject.

339
contrib/sslinfo/sslinfo.c Normal file
View File

@ -0,0 +1,339 @@
/*
* module for PostgreSQL to access client SSL certificate information
*
* Copyright (c) Cryptocom LTD, 2006
* Written by Victor B. Wagner <vitus@cryptocom.ru>
* This file is distributed under BSD-style license.
*/
#include "postgres.h"
#include "fmgr.h"
#include "utils/numeric.h"
#include "libpq/libpq-be.h"
#include "miscadmin.h"
#include "utils/builtins.h"
#include "mb/pg_wchar.h"
#include <openssl/x509.h>
#include <openssl/asn1.h>
PG_MODULE_MAGIC;
Datum ssl_is_used(PG_FUNCTION_ARGS);
Datum ssl_client_cert_present(PG_FUNCTION_ARGS);
Datum ssl_client_serial(PG_FUNCTION_ARGS);
Datum ssl_client_dn_field(PG_FUNCTION_ARGS);
Datum ssl_issuer_field(PG_FUNCTION_ARGS);
Datum ssl_client_dn(PG_FUNCTION_ARGS);
Datum ssl_issuer_dn(PG_FUNCTION_ARGS);
Datum X509_NAME_field_to_text(X509_NAME *name, text *fieldName);
Datum X509_NAME_to_text(X509_NAME *name);
Datum ASN1_STRING_to_text(ASN1_STRING *str);
/*
* Indicates whether current session uses SSL
*
* Function has no arguments. Returns bool. True if current session
* is SSL session and false if it is local or non-ssl session.
*/
PG_FUNCTION_INFO_V1(ssl_is_used);
Datum ssl_is_used(PG_FUNCTION_ARGS)
{
PG_RETURN_BOOL(MyProcPort->ssl !=NULL);
}
/*
* Indicates whether current client have provided a certificate
*
* Function has no arguments. Returns bool. True if current session
* is SSL session and client certificate is verified, otherwise false.
*/
PG_FUNCTION_INFO_V1(ssl_client_cert_present);
Datum ssl_client_cert_present(PG_FUNCTION_ARGS)
{
PG_RETURN_BOOL(MyProcPort->peer != NULL);
}
/*
* Returns serial number of certificate used to establish current
* session
*
* Function has no arguments. It returns the certificate serial
* number as numeric or null if current session doesn't use SSL or if
* SSL connection is established without sending client certificate.
*/
PG_FUNCTION_INFO_V1(ssl_client_serial);
Datum ssl_client_serial(PG_FUNCTION_ARGS)
{
Datum result;
Port *port = MyProcPort;
X509 *peer = port->peer;
ASN1_INTEGER *serial = NULL;
BIGNUM *b;
char *decimal;
if (!peer)
PG_RETURN_NULL();
serial = X509_get_serialNumber(peer);
b = ASN1_INTEGER_to_BN(serial, NULL);
decimal = BN_bn2dec(b);
BN_free(b);
result = DirectFunctionCall3(numeric_in,
CStringGetDatum(decimal),
ObjectIdGetDatum(0),
Int32GetDatum(-1));
OPENSSL_free(decimal);
return result;
}
/*
* Converts OpenSSL ASN1_STRING structure into text
*
* Converts ASN1_STRING into text, converting all the characters into
* current database encoding if possible. Any invalid characters are
* replaced by question marks.
*
* Parameter: str - OpenSSL ASN1_STRING structure. Memory managment
* of this structure is responsibility of caller.
*
* Returns Datum, which can be directly returned from a C language SQL
* function.
*/
Datum ASN1_STRING_to_text(ASN1_STRING *str)
{
BIO *membuf = NULL;
size_t size, outlen;
char *sp;
char *dp;
text *result;
membuf = BIO_new(BIO_s_mem());
BIO_set_close(membuf, BIO_CLOSE);
ASN1_STRING_print_ex(membuf,str,
((ASN1_STRFLGS_RFC2253 & ~ASN1_STRFLGS_ESC_MSB)
| ASN1_STRFLGS_UTF8_CONVERT));
outlen = 0;
BIO_write(membuf, &outlen, 1);
size = BIO_get_mem_data(membuf, &sp);
dp = pg_do_encoding_conversion(sp, size-1, PG_UTF8, GetDatabaseEncoding());
outlen = strlen(dp);
result = palloc(VARHDRSZ + outlen);
memcpy(VARDATA(result), dp, outlen);
if (dp != sp)
pfree(dp);
BIO_free(membuf);
VARATT_SIZEP(result) = outlen + VARHDRSZ;
PG_RETURN_TEXT_P(result);
}
/*
* Returns specified field of specified X509_NAME structure
*
* Common part of ssl_client_dn and ssl_issuer_dn functions.
*
* Parameter: X509_NAME *name - either subject or issuer of certificate
* Parameter: text fieldName - field name string like 'CN' or commonName
* to be looked up in the OpenSSL ASN1 OID database
*
* Returns result of ASN1_STRING_to_text applied to appropriate
* part of name
*/
Datum X509_NAME_field_to_text(X509_NAME *name, text *fieldName)
{
char *sp;
char *string_fieldname;
char *dp;
size_t name_len = VARSIZE(fieldName) - VARHDRSZ;
int nid, index, i;
ASN1_STRING *data;
string_fieldname = palloc(name_len + 1);
sp = VARDATA(fieldName);
dp = string_fieldname;
for (i = 0; i < name_len; i++)
*dp++ = *sp++;
*dp = '\0';
nid = OBJ_txt2nid(string_fieldname);
if (nid == NID_undef)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid X.509 field name: \"%s\"",
string_fieldname)));
pfree(string_fieldname);
index = X509_NAME_get_index_by_NID(name, nid, -1);
if (index < 0)
return (Datum)0;
data = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, index));
return ASN1_STRING_to_text(data);
}
/*
* Returns specified field of client certificate distinguished name
*
* Receives field name (like 'commonName' and 'emailAddress') and
* returns appropriate part of certificate subject converted into
* database encoding.
*
* Parameter: fieldname text - will be looked up in OpenSSL object
* identifier database
*
* Returns text string with appropriate value.
*
* Throws an error if argument cannot be converted into ASN1 OID by
* OpenSSL. Returns null if no client certificate is present, or if
* there is no field with such name in the certificate.
*/
PG_FUNCTION_INFO_V1(ssl_client_dn_field);
Datum ssl_client_dn_field(PG_FUNCTION_ARGS)
{
text *fieldname = PG_GETARG_TEXT_P(0);
Datum result;
if (!(MyProcPort->peer))
PG_RETURN_NULL();
result = X509_NAME_field_to_text(X509_get_subject_name(MyProcPort->peer), fieldname);
if (!result)
PG_RETURN_NULL();
else
return result;
}
/*
* Returns specified field of client certificate issuer name
*
* Receives field name (like 'commonName' and 'emailAddress') and
* returns appropriate part of certificate subject converted into
* database encoding.
*
* Parameter: fieldname text - would be looked up in OpenSSL object
* identifier database
*
* Returns text string with appropriate value.
*
* Throws an error if argument cannot be converted into ASN1 OID by
* OpenSSL. Returns null if no client certificate is present, or if
* there is no field with such name in the certificate.
*/
PG_FUNCTION_INFO_V1(ssl_issuer_field);
Datum ssl_issuer_field(PG_FUNCTION_ARGS)
{
text *fieldname = PG_GETARG_TEXT_P(0);
Datum result;
if (!(MyProcPort->peer))
PG_RETURN_NULL();
result = X509_NAME_field_to_text(X509_get_issuer_name(MyProcPort->peer), fieldname);
if (!result)
PG_RETURN_NULL();
else
return result;
}
/*
* Equivalent of X509_NAME_oneline that respects encoding
*
* This function converts X509_NAME structure to the text variable
* converting all textual data into current database encoding.
*
* Parameter: X509_NAME *name X509_NAME structure to be converted
*
* Returns: text datum which contains string representation of
* X509_NAME
*/
Datum X509_NAME_to_text(X509_NAME *name)
{
BIO *membuf = BIO_new(BIO_s_mem());
int i,nid,count = X509_NAME_entry_count(name);
X509_NAME_ENTRY *e;
ASN1_STRING *v;
const char *field_name;
size_t size,outlen;
char *sp;
char *dp;
text *result;
BIO_set_close(membuf, BIO_CLOSE);
for (i=0; i<count; i++)
{
e = X509_NAME_get_entry(name, i);
nid = OBJ_obj2nid(X509_NAME_ENTRY_get_object(e));
v = X509_NAME_ENTRY_get_data(e);
field_name = OBJ_nid2sn(nid);
if (!field_name)
field_name = OBJ_nid2ln(nid);
BIO_printf(membuf, "/%s=", field_name);
ASN1_STRING_print_ex(membuf,v,
((ASN1_STRFLGS_RFC2253 & ~ASN1_STRFLGS_ESC_MSB)
| ASN1_STRFLGS_UTF8_CONVERT));
}
i=0;
BIO_write(membuf, &i, 1);
size = BIO_get_mem_data(membuf, &sp);
dp = pg_do_encoding_conversion(sp, size-1, PG_UTF8, GetDatabaseEncoding());
BIO_free(membuf);
outlen = strlen(dp);
result = palloc(VARHDRSZ + outlen);
memcpy(VARDATA(result), dp, outlen);
/* pg_do_encoding_conversion has annoying habit of returning
* source pointer */
if (dp != sp)
pfree(dp);
VARATT_SIZEP(result) = outlen + VARHDRSZ;
PG_RETURN_TEXT_P(result);
}
/*
* Returns current client certificate subject as one string
*
* This function returns distinguished name (subject) of the client
* certificate used in the current SSL connection, converting it into
* the current database encoding.
*
* Returns text datum.
*/
PG_FUNCTION_INFO_V1(ssl_client_dn);
Datum ssl_client_dn(PG_FUNCTION_ARGS)
{
if (!(MyProcPort->peer))
PG_RETURN_NULL();
return X509_NAME_to_text(X509_get_subject_name(MyProcPort->peer));
}
/*
* Returns current client certificate issuer as one string
*
* This function returns issuer's distinguished name of the client
* certificate used in the current SSL connection, converting it into
* the current database encoding.
*
* Returns text datum.
*/
PG_FUNCTION_INFO_V1(ssl_issuer_dn);
Datum ssl_issuer_dn(PG_FUNCTION_ARGS)
{
if (!(MyProcPort->peer))
PG_RETURN_NULL();
return X509_NAME_to_text(X509_get_issuer_name(MyProcPort->peer));
}

View File

@ -0,0 +1,29 @@
SET search_path = public;
CREATE OR REPLACE FUNCTION ssl_client_serial() RETURNS numeric
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', 'ssl_client_serial';
CREATE OR REPLACE FUNCTION ssl_is_used() RETURNS boolean
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', 'ssl_is_used';
CREATE OR REPLACE FUNCTION ssl_client_cert_present() RETURNS boolean
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', 'ssl_client_cert_present';
CREATE OR REPLACE FUNCTION ssl_client_dn_field(text) RETURNS text
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', 'ssl_client_dn_field';
CREATE OR REPLACE FUNCTION ssl_issuer_field(text) RETURNS text
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', 'ssl_issuer_field';
CREATE OR REPLACE FUNCTION ssl_client_dn() RETURNS text
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', 'ssl_client_dn';
CREATE OR REPLACE FUNCTION ssl_issuer_dn() RETURNS text
LANGUAGE C STRICT
AS 'MODULE_PATHNAME', 'ssl_issuer_dn';

View File

@ -13,7 +13,7 @@
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/miscadmin.h,v 1.188 2006/08/15 18:26:59 tgl Exp $
* $PostgreSQL: pgsql/src/include/miscadmin.h,v 1.189 2006/09/04 15:07:46 petere Exp $
*
* NOTES
* some of the information in this file should be moved to other files.
@ -131,7 +131,7 @@ extern DLLIMPORT int NBuffers;
extern int MaxBackends;
extern DLLIMPORT int MyProcPid;
extern struct Port *MyProcPort;
extern DLLIMPORT struct Port *MyProcPort;
extern long MyCancelKey;
extern char OutputFileName[];