We can't always read 6 bytes in an OCSP response: fix so error statuses
[openssl.git] / crypto / ocsp / ocsp_ht.c
index b78cd3709215d2e0c36b8227552de6371f5addf3..af5fc16691d432d4969126a5e64640e4a1775a14 100644 (file)
@@ -1,9 +1,9 @@
 /* ocsp_ht.c */
-/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
- * project 2000.
+/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
+ * project 2006.
  */
 /* ====================================================================
- * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
+ * 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
  *
  */
 
-#include <openssl/asn1.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <ctype.h>
 #include <string.h>
+#include "e_os.h"
+#include <openssl/asn1.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 */
 
-/* Quick and dirty HTTP OCSP request handler.
- * Could make this a bit cleverer by adding
- * support for non blocking BIOs and a few
- * other refinements.
- */
+/* Stateful OCSP request code, supporting non-blocking I/O */
 
-OCSP_RESPONSE *OCSP_sendreq_bio(BIO *b, char *path, OCSP_REQUEST *req)
-{
-       BIO *mem = NULL;
-       char tmpbuf[1024];
-       OCSP_RESPONSE *resp = NULL;
-       char *p, *q, *r;
-       int len, retcode;
-       static char req_txt[] =
-"POST %s HTTP/1.0\r\n\
-Content-Type: application/ocsp-request\r\n\
-Content-Length: %d\r\n\r\n";
-
-       len = i2d_OCSP_REQUEST(req, NULL);
-       if(BIO_printf(b, req_txt, path, len) < 0) {
-               OCSPerr(OCSP_F_OCSP_SENDREQ_BIO,OCSP_R_SERVER_WRITE_ERROR);
-               goto err;
+/* 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);
        }
-       if(i2d_OCSP_REQUEST_bio(b, req) <= 0) {
-               OCSPerr(OCSP_F_OCSP_SENDREQ_BIO,OCSP_R_SERVER_WRITE_ERROR);
-               goto err;
+
+int OCSP_REQ_CTX_set1_req(OCSP_REQ_CTX *rctx, OCSP_REQUEST *req)
+       {
+       static const char req_hdr[] =
+       "Content-Type: application/ocsp-request\r\n"
+       "Content-Length: %d\r\n\r\n";
+        if (BIO_printf(rctx->mem, req_hdr, i2d_OCSP_REQUEST(req, NULL)) <= 0)
+               return 0;
+        if (i2d_OCSP_REQUEST_bio(rctx->mem, req) <= 0)
+               return 0;
+       rctx->state = OHS_ASN1_WRITE;
+       rctx->asn1_len = BIO_get_mem_data(rctx->mem, NULL);
+       return 1;
        }
-       if(!(mem = BIO_new(BIO_s_mem()))) goto err;
-       /* Copy response to a memory BIO: socket bios can't do gets! */
-       while ((len = BIO_read(b, tmpbuf, 1024))) {
-               if(len < 0) {
-                       OCSPerr(OCSP_F_OCSP_SENDREQ_BIO,OCSP_R_SERVER_READ_ERROR);
-                       goto err;
+
+int OCSP_REQ_CTX_add1_header(OCSP_REQ_CTX *rctx,
+               const char *name, const char *value)
+       {
+       if (!name)
+               return 0;
+       if (BIO_puts(rctx->mem, name) <= 0)
+               return 0;
+       if (value)
+               {
+               if (BIO_write(rctx->mem, ": ", 2) != 2)
+                       return 0;
+               if (BIO_puts(rctx->mem, value) <= 0)
+                       return 0;
                }
-               BIO_write(mem, tmpbuf, len);
+       if (BIO_write(rctx->mem, "\r\n", 2) != 2)
+               return 0;
+       return 1;
        }
-       if(BIO_gets(mem, tmpbuf, 512) <= 0) {
-               OCSPerr(OCSP_F_OCSP_SENDREQ_BIO,OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
-               goto err;
+
+OCSP_REQ_CTX *OCSP_sendreq_new(BIO *io, char *path, OCSP_REQUEST *req,
+                                                               int maxline)
+       {
+       static const char post_hdr[] = "POST %s HTTP/1.0\r\n";
+
+       OCSP_REQ_CTX *rctx;
+       rctx = OPENSSL_malloc(sizeof(OCSP_REQ_CTX));
+       rctx->state = OHS_ERROR;
+       rctx->mem = BIO_new(BIO_s_mem());
+       rctx->io = io;
+       rctx->asn1_len = 0;
+       if (maxline > 0)
+               rctx->iobuflen = maxline;
+       else
+               rctx->iobuflen = OCSP_MAX_LINE_LEN;
+       rctx->iobuf = OPENSSL_malloc(rctx->iobuflen);
+       if (!rctx->iobuf)
+               return 0;
+       if (!path)
+               path = "/";
+
+        if (BIO_printf(rctx->mem, post_hdr, path) <= 0)
+               return 0;
+
+       if (req && !OCSP_REQ_CTX_set1_req(rctx, req))
+               return 0;
+
+       return rctx;
        }
-       /* Parse the HTTP response. This will look like this:
-        * "HTTP/1.0 200 OK". We need to obtain the numeric code and
-         * informational message.
-        */
 
+/* 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 = tmpbuf; *p && !isspace((unsigned char)*p); p++) continue;
-       if(!*p) {
-               OCSPerr(OCSP_F_OCSP_SENDREQ_BIO,OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
-               goto err;
-       }
+
+       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_OCSP_SENDREQ_BIO,OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
-               goto err;
-       }
+       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_OCSP_SENDREQ_BIO,OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
-               goto err;
-       }
+       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) goto err;
+
+       if(*r)
+               return 0;
+
        /* Skip over any leading white space in message */
-       while(*q && isspace((unsigned char)*q))  q++;
-       if(!*q) goto err;
-       /* 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_OCSP_SENDREQ_BIO,OCSP_R_SERVER_RESPONSE_ERROR);
-               ERR_add_error_data(4, "Code=", p, ",Reason=", q);
-               goto err;
+       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;
+
        }
-       /* Find blank line marking beginning of content */      
-       while(BIO_gets(mem, tmpbuf, 512) > 0)
+
+int OCSP_sendreq_nbio(OCSP_RESPONSE **presp, OCSP_REQ_CTX *rctx)
        {
-               for(p = tmpbuf; *p && isspace((unsigned char)*p); p++) continue;
-               if(!*p) break;
-       }
-       if(*p) {
-               OCSPerr(OCSP_F_OCSP_SENDREQ_BIO,OCSP_R_NO_CONTENT);
-               goto err;
+       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 2 bytes which
+                * is enough for ASN1 SEQUENCE header and either length field
+                * or at least the length of the length field.
+                */
+               n = BIO_get_mem_data(rctx->mem, &p);
+               if (n < 2)
+                       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)
+                       {
+                       /* If MSB set on initial length octet we can now
+                        * always read 6 octets: make sure we have them.
+                        */
+                       if (n < 6)
+                               goto next_io;
+                       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;
+
+
        }
-       if(!(resp = d2i_OCSP_RESPONSE_bio(mem, NULL))) {
-               OCSPerr(OCSP_F_OCSP_SENDREQ_BIO,ERR_R_NESTED_ASN1_ERROR);
-               goto err;
+
+/* 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;
        }
-       err:
-       BIO_free(mem);
-       return resp;
-}