/* ocsp_ht.c */
/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
* project 2006.
*/
/* ====================================================================
* Copyright (c) 2006 The OpenSSL Project. 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.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* licensing@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED 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 OpenSSL PROJECT OR
* ITS 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.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
#include <openssl/asn1.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <openssl/ocsp.h>
#include <openssl/err.h>
#include <openssl/buffer.h>
#ifdef OPENSSL_SYS_SUNOS
#define strtoul (unsigned long)strtol
#endif /* OPENSSL_SYS_SUNOS */
/* Stateful OCSP request code, supporting non-blocking I/O */
/* Opaque OCSP request status structure */
struct ocsp_req_ctx_st {
int state; /* Current I/O state */
unsigned char *iobuf; /* Line buffer */
int iobuflen; /* Line buffer length */
BIO *io; /* BIO to perform I/O with */
BIO *mem; /* Memory BIO response is built into */
unsigned long asn1_len; /* ASN1 length of response */
};
#define OCSP_MAX_REQUEST_LENGTH (100 * 1024)
#define OCSP_MAX_LINE_LEN 4096;
/* OCSP states */
/* If set no reading should be performed */
#define OHS_NOREAD 0x1000
/* Error condition */
#define OHS_ERROR (0 | OHS_NOREAD)
/* First line being read */
#define OHS_FIRSTLINE 1
/* MIME headers being read */
#define OHS_HEADERS 2
/* OCSP initial header (tag + length) being read */
#define OHS_ASN1_HEADER 3
/* OCSP content octets being read */
#define OHS_ASN1_CONTENT 4
/* Request being sent */
#define OHS_ASN1_WRITE (6 | OHS_NOREAD)
/* Request being flushed */
#define OHS_ASN1_FLUSH (7 | OHS_NOREAD)
/* Completed */
#define OHS_DONE (8 | OHS_NOREAD)
static int parse_http_line1(char *line);
void OCSP_REQ_CTX_free(OCSP_REQ_CTX *rctx)
{
if (rctx->mem)
BIO_free(rctx->mem);
if (rctx->iobuf)
OPENSSL_free(rctx->iobuf);
OPENSSL_free(rctx);
}
OCSP_REQ_CTX *OCSP_sendreq_new(BIO *io, char *path, OCSP_REQUEST *req,
int maxline)
{
static char post_hdr[] = "POST %s HTTP/1.0\r\n"
"Content-Type: application/ocsp-request\r\n"
"Content-Length: %d\r\n\r\n";
OCSP_REQ_CTX *rctx;
rctx = OPENSSL_malloc(sizeof(OCSP_REQ_CTX));
rctx->state = OHS_FIRSTLINE;
rctx->mem = BIO_new(BIO_s_mem());
rctx->io = io;
if (maxline > 0)
rctx->iobuflen = maxline;
else
rctx->iobuflen = OCSP_MAX_LINE_LEN;
rctx->iobuf = OPENSSL_malloc(rctx->iobuflen);
if (!path)
path = "/";
if (BIO_printf(rctx->mem, post_hdr, path,
i2d_OCSP_REQUEST(req, NULL)) <= 0)
{
rctx->state = OHS_ERROR;
return 0;
}
if (i2d_OCSP_REQUEST_bio(rctx->mem, req) <= 0)
{
rctx->state = OHS_ERROR;
return 0;
}
rctx->state = OHS_ASN1_WRITE;
rctx->asn1_len = BIO_get_mem_data(rctx->mem, NULL);
return rctx;
}
/* Parse the HTTP response. This will look like this:
* "HTTP/1.0 200 OK". We need to obtain the numeric code and
* (optional) informational message.
*/
static int parse_http_line1(char *line)
{
int retcode;
char *p, *q, *r;
/* Skip to first white space (passed protocol info) */
for(p = line; *p && !isspace((unsigned char)*p); p++)
continue;
if(!*p)
{
OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
return 0;
}
/* Skip past white space to start of response code */
while(*p && isspace((unsigned char)*p))
p++;
if(!*p)
{
OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
return 0;
}
/* Find end of response code: first whitespace after start of code */
for(q = p; *q && !isspace((unsigned char)*q); q++)
continue;
if(!*q)
{
OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
return 0;
}
/* Set end of response code and start of message */
*q++ = 0;
/* Attempt to parse numeric code */
retcode = strtoul(p, &r, 10);
if(*r)
return 0;
/* Skip over any leading white space in message */
while(*q && isspace((unsigned char)*q))
q++;
if(*q)
{
/* Finally zap any trailing white space in message (include
* CRLF) */
/* We know q has a non white space character so this is OK */
for(r = q + strlen(q) - 1; isspace((unsigned char)*r); r--)
*r = 0;
}
if(retcode != 200)
{
OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_ERROR);
if(!*q)
ERR_add_error_data(2, "Code=", p);
else
ERR_add_error_data(4, "Code=", p, ",Reason=", q);
return 0;
}
return 1;
}
int OCSP_sendreq_nbio(OCSP_RESPONSE **presp, OCSP_REQ_CTX *rctx)
{
int i, n;
const unsigned char *p;
next_io:
if (!(rctx->state & OHS_NOREAD))
{
n = BIO_read(rctx->io, rctx->iobuf, rctx->iobuflen);
if (n <= 0)
{
if (BIO_should_retry(rctx->io))
return -1;
return 0;
}
/* Write data to memory BIO */
if (BIO_write(rctx->mem, rctx->iobuf, n) != n)
return 0;
}
switch(rctx->state)
{
case OHS_ASN1_WRITE:
n = BIO_get_mem_data(rctx->mem, &p);
i = BIO_write(rctx->io,
p + (n - rctx->asn1_len), rctx->asn1_len);
if (i <= 0)
{
if (BIO_should_retry(rctx->io))
return -1;
rctx->state = OHS_ERROR;
return 0;
}
rctx->asn1_len -= i;
if (rctx->asn1_len > 0)
goto next_io;
rctx->state = OHS_ASN1_FLUSH;
(void)BIO_reset(rctx->mem);
case OHS_ASN1_FLUSH:
i = BIO_flush(rctx->io);
if (i > 0)
{
rctx->state = OHS_FIRSTLINE;
goto next_io;
}
if (BIO_should_retry(rctx->io))
return -1;
rctx->state = OHS_ERROR;
return 0;
case OHS_ERROR:
return 0;
case OHS_FIRSTLINE:
case OHS_HEADERS:
/* Attempt to read a line in */
next_line:
/* Due to &%^*$" memory BIO behaviour with BIO_gets we
* have to check there's a complete line in there before
* calling BIO_gets or we'll just get a partial read.
*/
n = BIO_get_mem_data(rctx->mem, &p);
if ((n <= 0) || !memchr(p, '\n', n))
{
if (n >= rctx->iobuflen)
{
rctx->state = OHS_ERROR;
return 0;
}
goto next_io;
}
n = BIO_gets(rctx->mem, (char *)rctx->iobuf, rctx->iobuflen);
if (n <= 0)
{
if (BIO_should_retry(rctx->mem))
goto next_io;
rctx->state = OHS_ERROR;
return 0;
}
/* Don't allow excessive lines */
if (n == rctx->iobuflen)
{
rctx->state = OHS_ERROR;
return 0;
}
/* First line */
if (rctx->state == OHS_FIRSTLINE)
{
if (parse_http_line1((char *)rctx->iobuf))
{
rctx->state = OHS_HEADERS;
goto next_line;
}
else
{
rctx->state = OHS_ERROR;
return 0;
}
}
else
{
/* Look for blank line: end of headers */
for (p = rctx->iobuf; *p; p++)
{
if ((*p != '\r') && (*p != '\n'))
break;
}
if (*p)
goto next_line;
rctx->state = OHS_ASN1_HEADER;
}
/* Fall thru */
case OHS_ASN1_HEADER:
/* Now reading ASN1 header: can read at least 6 bytes which
* is more than enough for any valid ASN1 SEQUENCE header
*/
n = BIO_get_mem_data(rctx->mem, &p);
if (n < 6)
goto next_io;
/* Check it is an ASN1 SEQUENCE */
if (*p++ != (V_ASN1_SEQUENCE|V_ASN1_CONSTRUCTED))
{
rctx->state = OHS_ERROR;
return 0;
}
/* Check out length field */
if (*p & 0x80)
{
n = *p & 0x7F;
/* Not NDEF or excessive length */
if (!n || (n > 4))
{
rctx->state = OHS_ERROR;
return 0;
}
p++;
rctx->asn1_len = 0;
for (i = 0; i < n; i++)
{
rctx->asn1_len <<= 8;
rctx->asn1_len |= *p++;
}
if (rctx->asn1_len > OCSP_MAX_REQUEST_LENGTH)
{
rctx->state = OHS_ERROR;
return 0;
}
rctx->asn1_len += n + 2;
}
else
rctx->asn1_len = *p + 2;
rctx->state = OHS_ASN1_CONTENT;
/* Fall thru */
case OHS_ASN1_CONTENT:
n = BIO_get_mem_data(rctx->mem, &p);
if (n < (int)rctx->asn1_len)
goto next_io;
*presp = d2i_OCSP_RESPONSE(NULL, &p, rctx->asn1_len);
if (*presp)
{
rctx->state = OHS_DONE;
return 1;
}
rctx->state = OHS_ERROR;
return 0;
break;
case OHS_DONE:
return 1;
}
return 0;
}
/* Blocking OCSP request handler: now a special case of non-blocking I/O */
OCSP_RESPONSE *OCSP_sendreq_bio(BIO *b, char *path, OCSP_REQUEST *req)
{
OCSP_RESPONSE *resp = NULL;
OCSP_REQ_CTX *ctx;
int rv;
ctx = OCSP_sendreq_new(b, path, req, -1);
do
{
rv = OCSP_sendreq_nbio(&resp, ctx);
} while ((rv == -1) && BIO_should_retry(b));
OCSP_REQ_CTX_free(ctx);
if (rv)
return resp;
return NULL;
}