LCOV - code coverage report
Current view: top level - source3/registry - reg_parse_prs.c (source / functions) Hit Total Coverage
Test: coverage report for master 2b515b7d Lines: 99 170 58.2 %
Date: 2024-02-28 12:06:22 Functions: 16 20 80.0 %

          Line data    Source code
       1             : /*
       2             :    Unix SMB/CIFS implementation.
       3             :    Samba memory buffer functions
       4             :    Copyright (C) Andrew Tridgell              1992-1997
       5             :    Copyright (C) Luke Kenneth Casson Leighton 1996-1997
       6             :    Copyright (C) Jeremy Allison               1999
       7             :    Copyright (C) Andrew Bartlett              2003.
       8             : 
       9             :    This program is free software; you can redistribute it and/or modify
      10             :    it under the terms of the GNU General Public License as published by
      11             :    the Free Software Foundation; either version 3 of the License, or
      12             :    (at your option) any later version.
      13             : 
      14             :    This program is distributed in the hope that it will be useful,
      15             :    but WITHOUT ANY WARRANTY; without even the implied warranty of
      16             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      17             :    GNU General Public License for more details.
      18             : 
      19             :    You should have received a copy of the GNU General Public License
      20             :    along with this program.  If not, see <http://www.gnu.org/licenses/>.
      21             : */
      22             : 
      23             : #include "includes.h"
      24             : #include "reg_parse_prs.h"
      25             : #include "rpc_dce.h"
      26             : 
      27             : #undef DBGC_CLASS
      28             : #define DBGC_CLASS DBGC_RPC_PARSE
      29             : 
      30           0 : static const char *tab_depth(int level, int depth)
      31             : {
      32           0 :         if( CHECK_DEBUGLVL(level) ) {
      33           0 :                 dbgtext("%*s", depth*4, "");
      34             :         }
      35           0 :         return "";
      36             : }
      37             : 
      38             : /*******************************************************************
      39             :  Debug output for parsing info
      40             : 
      41             :  XXXX side-effect of this function is to increase the debug depth XXXX.
      42             : 
      43             : ********************************************************************/
      44             : 
      45          26 : void prs_debug(prs_struct *ps, int depth, const char *desc, const char *fn_name)
      46             : {
      47          26 :         DEBUG(5+depth, ("%s%06x %s %s\n", tab_depth(5+depth,depth), ps->data_offset, fn_name, desc));
      48          26 : }
      49             : 
      50             : /**
      51             :  * Initialise an expandable parse structure.
      52             :  *
      53             :  * @param size Initial buffer size.  If >0, a new buffer will be
      54             :  * created with talloc().
      55             :  *
      56             :  * @return False if allocation fails, otherwise True.
      57             :  **/
      58             : 
      59           8 : bool prs_init(prs_struct *ps, uint32_t size, TALLOC_CTX *ctx, bool io)
      60             : {
      61           8 :         ZERO_STRUCTP(ps);
      62           8 :         ps->io = io;
      63           8 :         ps->bigendian_data = RPC_LITTLE_ENDIAN;
      64           8 :         ps->align = RPC_PARSE_ALIGN;
      65           8 :         ps->is_dynamic = False;
      66           8 :         ps->data_offset = 0;
      67           8 :         ps->buffer_size = 0;
      68           8 :         ps->data_p = NULL;
      69           8 :         ps->mem_ctx = ctx;
      70             : 
      71           8 :         if (size != 0) {
      72           8 :                 ps->buffer_size = size;
      73           8 :                 ps->data_p = (char *)talloc_zero_size(ps->mem_ctx, size);
      74           8 :                 if(ps->data_p == NULL) {
      75           0 :                         DEBUG(0,("prs_init: talloc fail for %u bytes.\n", (unsigned int)size));
      76           0 :                         return False;
      77             :                 }
      78           8 :                 ps->is_dynamic = True; /* We own this memory. */
      79           0 :         } else if (MARSHALLING(ps)) {
      80             :                 /* If size is zero and we're marshalling we should allocate memory on demand. */
      81           0 :                 ps->is_dynamic = True;
      82             :         }
      83             : 
      84           0 :         return True;
      85             : }
      86             : 
      87             : /*******************************************************************
      88             :  Delete the memory in a parse structure - if we own it.
      89             : 
      90             :  NOTE: Contrary to the somewhat confusing naming, this function is not
      91             :        intended for freeing memory allocated by prs_alloc_mem().
      92             :        That memory is also attached to the talloc context given by
      93             :        ps->mem_ctx, but is only freed when that talloc context is
      94             :        freed. prs_mem_free() is used to delete "dynamic" memory
      95             :        allocated in marshalling/unmarshalling.
      96             :  ********************************************************************/
      97             : 
      98           6 : void prs_mem_free(prs_struct *ps)
      99             : {
     100           6 :         if(ps->is_dynamic) {
     101           5 :                 TALLOC_FREE(ps->data_p);
     102             :         }
     103           6 :         ps->is_dynamic = False;
     104           6 :         ps->buffer_size = 0;
     105           6 :         ps->data_offset = 0;
     106           6 : }
     107             : 
     108             : /*******************************************************************
     109             :  Allocate memory when unmarshalling... Always zero clears.
     110             :  ********************************************************************/
     111             : 
     112             : #if defined(PARANOID_MALLOC_CHECKER)
     113           1 : char *prs_alloc_mem_(prs_struct *ps, size_t size, unsigned int count)
     114             : #else
     115             : char *prs_alloc_mem(prs_struct *ps, size_t size, unsigned int count)
     116             : #endif
     117             : {
     118           1 :         char *ret = NULL;
     119             : 
     120           1 :         if (size && count) {
     121             :                 /* We can't call the type-safe version here. */
     122           1 :                 ret = (char *)_talloc_zero_array(ps->mem_ctx, size, count,
     123             :                                                  "parse_prs");
     124             :         }
     125           1 :         return ret;
     126             : }
     127             : 
     128             : /*******************************************************************
     129             :  Return the current talloc context we're using.
     130             :  ********************************************************************/
     131             : 
     132           1 : TALLOC_CTX *prs_get_mem_context(prs_struct *ps)
     133             : {
     134           1 :         return ps->mem_ctx;
     135             : }
     136             : 
     137             : /*******************************************************************
     138             :  Attempt, if needed, to grow a data buffer.
     139             :  Also depends on the data stream mode (io).
     140             :  ********************************************************************/
     141             : 
     142         119 : bool prs_grow(prs_struct *ps, uint32_t extra_space)
     143             : {
     144         119 :         uint32_t new_size;
     145             : 
     146         119 :         ps->grow_size = MAX(ps->grow_size, ps->data_offset + extra_space);
     147             : 
     148         119 :         if(ps->data_offset + extra_space <= ps->buffer_size)
     149           0 :                 return True;
     150             : 
     151             :         /*
     152             :          * We cannot grow the buffer if we're not reading
     153             :          * into the prs_struct, or if we don't own the memory.
     154             :          */
     155             : 
     156           1 :         if(UNMARSHALLING(ps) || !ps->is_dynamic) {
     157           1 :                 DEBUG(0,("prs_grow: Buffer overflow - unable to expand buffer by %u bytes.\n",
     158             :                                 (unsigned int)extra_space));
     159           1 :                 return False;
     160             :         }
     161             : 
     162             :         /*
     163             :          * Decide how much extra space we really need.
     164             :          */
     165             : 
     166           0 :         extra_space -= (ps->buffer_size - ps->data_offset);
     167           0 :         if(ps->buffer_size == 0) {
     168             : 
     169             :                 /*
     170             :                  * Start with 128 bytes (arbitrary value), enough for small rpc
     171             :                  * requests
     172             :                  */
     173           0 :                 new_size = MAX(128, extra_space);
     174             : 
     175           0 :                 ps->data_p = (char *)talloc_zero_size(ps->mem_ctx, new_size);
     176           0 :                 if(ps->data_p == NULL) {
     177           0 :                         DEBUG(0,("prs_grow: talloc failure for size %u.\n", (unsigned int)new_size));
     178           0 :                         return False;
     179             :                 }
     180             :         } else {
     181             :                 /*
     182             :                  * If the current buffer size is bigger than the space needed,
     183             :                  * just double it, else add extra_space. Always keep 64 bytes
     184             :                  * more, so that after we added a large blob we don't have to
     185             :                  * realloc immediately again.
     186             :                  */
     187           0 :                 new_size = MAX(ps->buffer_size*2,
     188             :                                ps->buffer_size + extra_space + 64);
     189             : 
     190           0 :                 ps->data_p = talloc_realloc(ps->mem_ctx,
     191             :                                                 ps->data_p,
     192             :                                                 char,
     193             :                                                 new_size);
     194           0 :                 if (ps->data_p == NULL) {
     195           0 :                         DEBUG(0,("prs_grow: Realloc failure for size %u.\n",
     196             :                                 (unsigned int)new_size));
     197           0 :                         return False;
     198             :                 }
     199             : 
     200           0 :                 memset(&ps->data_p[ps->buffer_size], '\0', (size_t)(new_size - ps->buffer_size));
     201             :         }
     202           0 :         ps->buffer_size = new_size;
     203             : 
     204           0 :         return True;
     205             : }
     206             : 
     207             : /*******************************************************************
     208             :  Get the data pointer (external interface).
     209             : ********************************************************************/
     210             : 
     211          16 : char *prs_data_p(prs_struct *ps)
     212             : {
     213          16 :         return ps->data_p;
     214             : }
     215             : 
     216             : /*******************************************************************
     217             :  Get the current data size (external interface).
     218             :  ********************************************************************/
     219             : 
     220          14 : uint32_t prs_data_size(prs_struct *ps)
     221             : {
     222          14 :         return ps->buffer_size;
     223             : }
     224             : 
     225             : /*******************************************************************
     226             :  Fetch the current offset (external interface).
     227             :  ********************************************************************/
     228             : 
     229          28 : uint32_t prs_offset(prs_struct *ps)
     230             : {
     231          28 :         return ps->data_offset;
     232             : }
     233             : 
     234             : /*******************************************************************
     235             :  Set the current offset (external interface).
     236             :  ********************************************************************/
     237             : 
     238          80 : bool prs_set_offset(prs_struct *ps, uint32_t offset)
     239             : {
     240          80 :         if ((offset > ps->data_offset)
     241          36 :             && !prs_grow(ps, offset - ps->data_offset)) {
     242           0 :                 return False;
     243             :         }
     244             : 
     245          79 :         ps->data_offset = offset;
     246          79 :         return True;
     247             : }
     248             : 
     249             : /*******************************************************************
     250             :  Append the data from a buffer into a parse_struct.
     251             :  ********************************************************************/
     252             : 
     253           0 : bool prs_copy_data_in(prs_struct *dst, const char *src, uint32_t len)
     254             : {
     255           0 :         if (len == 0)
     256           0 :                 return True;
     257             : 
     258           0 :         if(!prs_grow(dst, len))
     259           0 :                 return False;
     260             : 
     261           0 :         memcpy(&dst->data_p[dst->data_offset], src, (size_t)len);
     262           0 :         dst->data_offset += len;
     263             : 
     264           0 :         return True;
     265             : }
     266             : 
     267             : /*******************************************************************
     268             :  Align the data_len to a multiple of align bytes - filling with
     269             :  zeros.
     270             :  ********************************************************************/
     271             : 
     272           9 : bool prs_align(prs_struct *ps)
     273             : {
     274           9 :         uint32_t mod = ps->data_offset & (ps->align-1);
     275             : 
     276           9 :         if (ps->align != 0 && mod != 0) {
     277           0 :                 uint32_t extra_space = (ps->align - mod);
     278           0 :                 if(!prs_grow(ps, extra_space))
     279           0 :                         return False;
     280           0 :                 memset(&ps->data_p[ps->data_offset], '\0', (size_t)extra_space);
     281           0 :                 ps->data_offset += extra_space;
     282             :         }
     283             : 
     284           0 :         return True;
     285             : }
     286             : 
     287             : /******************************************************************
     288             :  Align on a 8 byte boundary
     289             :  *****************************************************************/
     290             : 
     291           0 : bool prs_align_uint64(prs_struct *ps)
     292             : {
     293           0 :         bool ret;
     294           0 :         uint8_t old_align = ps->align;
     295             : 
     296           0 :         ps->align = 8;
     297           0 :         ret = prs_align(ps);
     298           0 :         ps->align = old_align;
     299             : 
     300           0 :         return ret;
     301             : }
     302             : 
     303             : /*******************************************************************
     304             :  Ensure we can read/write to a given offset.
     305             :  ********************************************************************/
     306             : 
     307         218 : char *prs_mem_get(prs_struct *ps, uint32_t extra_size)
     308             : {
     309         218 :         if(UNMARSHALLING(ps)) {
     310             :                 /*
     311             :                  * If reading, ensure that we can read the requested size item.
     312             :                  */
     313         135 :                 if (ps->data_offset + extra_size > ps->buffer_size) {
     314           0 :                         DEBUG(0,("prs_mem_get: reading data of size %u would overrun "
     315             :                                 "buffer by %u bytes.\n",
     316             :                                 (unsigned int)extra_size,
     317             :                                 (unsigned int)(ps->data_offset + extra_size - ps->buffer_size) ));
     318           0 :                         return NULL;
     319             :                 }
     320             :         } else {
     321             :                 /*
     322             :                  * Writing - grow the buffer if needed.
     323             :                  */
     324          83 :                 if(!prs_grow(ps, extra_size))
     325           0 :                         return NULL;
     326             :         }
     327         218 :         return &ps->data_p[ps->data_offset];
     328             : }
     329             : 
     330             : /*******************************************************************
     331             :  Change the struct type.
     332             :  ********************************************************************/
     333             : 
     334           1 : void prs_switch_type(prs_struct *ps, bool io)
     335             : {
     336           1 :         if ((ps->io ^ io) == True)
     337           1 :                 ps->io=io;
     338           1 : }
     339             : 
     340             : /*******************************************************************
     341             :  Stream a uint16.
     342             :  ********************************************************************/
     343             : 
     344          11 : bool prs_uint16(const char *name, prs_struct *ps, int depth, uint16_t *data16)
     345             : {
     346          11 :         char *q = prs_mem_get(ps, sizeof(uint16_t));
     347          11 :         if (q == NULL)
     348           0 :                 return False;
     349             : 
     350          11 :         if (UNMARSHALLING(ps)) {
     351           8 :                 if (ps->bigendian_data)
     352           0 :                         *data16 = RSVAL(q,0);
     353             :                 else
     354           8 :                         *data16 = SVAL(q,0);
     355             :         } else {
     356           3 :                 if (ps->bigendian_data)
     357           0 :                         RSSVAL(q,0,*data16);
     358             :                 else
     359           3 :                         SSVAL(q,0,*data16);
     360             :         }
     361             : 
     362          11 :         DEBUGADD(5,("%s%04x %s: %04x\n", tab_depth(5,depth), ps->data_offset, name, *data16));
     363             : 
     364          11 :         ps->data_offset += sizeof(uint16_t);
     365             : 
     366          11 :         return True;
     367             : }
     368             : 
     369             : /*******************************************************************
     370             :  Stream a uint32.
     371             :  ********************************************************************/
     372             : 
     373         184 : bool prs_uint32(const char *name, prs_struct *ps, int depth, uint32_t *data32)
     374             : {
     375         184 :         char *q = prs_mem_get(ps, sizeof(uint32_t));
     376         184 :         if (q == NULL)
     377           0 :                 return False;
     378             : 
     379         184 :         if (UNMARSHALLING(ps)) {
     380         110 :                 if (ps->bigendian_data)
     381           0 :                         *data32 = RIVAL(q,0);
     382             :                 else
     383         110 :                         *data32 = IVAL(q,0);
     384             :         } else {
     385          74 :                 if (ps->bigendian_data)
     386           0 :                         RSIVAL(q,0,*data32);
     387             :                 else
     388          74 :                         SIVAL(q,0,*data32);
     389             :         }
     390             : 
     391         184 :         DEBUGADD(5,("%s%04x %s: %08x\n", tab_depth(5,depth), ps->data_offset, name, *data32));
     392             : 
     393         184 :         ps->data_offset += sizeof(uint32_t);
     394             : 
     395         184 :         return True;
     396             : }
     397             : 
     398             : /*******************************************************************
     399             :  Stream a uint64_struct
     400             :  ********************************************************************/
     401           0 : bool prs_uint64(const char *name, prs_struct *ps, int depth, uint64_t *data64)
     402             : {
     403           0 :         if (UNMARSHALLING(ps)) {
     404           0 :                 uint32_t high, low;
     405             : 
     406           0 :                 if (!prs_uint32(name, ps, depth+1, &low))
     407           0 :                         return False;
     408             : 
     409           0 :                 if (!prs_uint32(name, ps, depth+1, &high))
     410           0 :                         return False;
     411             : 
     412           0 :                 *data64 = ((uint64_t)high << 32) + low;
     413             : 
     414           0 :                 return True;
     415             :         } else {
     416           0 :                 uint32_t high = (*data64) >> 32, low = (*data64) & 0xFFFFFFFF;
     417           0 :                 return prs_uint32(name, ps, depth+1, &low) &&
     418           0 :                            prs_uint32(name, ps, depth+1, &high);
     419             :         }
     420             : }
     421             : 
     422             : /******************************************************************
     423             :  Stream an array of uint8s. Length is number of uint8s.
     424             :  ********************************************************************/
     425             : 
     426          23 : bool prs_uint8s(bool charmode, const char *name, prs_struct *ps, int depth, uint8_t *data8s, int len)
     427             : {
     428          23 :         int i;
     429          23 :         char *q = prs_mem_get(ps, len);
     430          23 :         if (q == NULL)
     431           0 :                 return False;
     432             : 
     433          23 :         if (UNMARSHALLING(ps)) {
     434          63 :                 for (i = 0; i < len; i++)
     435          46 :                         data8s[i] = CVAL(q,i);
     436             :         } else {
     437          28 :                 for (i = 0; i < len; i++)
     438          22 :                         SCVAL(q, i, data8s[i]);
     439             :         }
     440             : 
     441          23 :         DEBUGADD(5,("%s%04x %s: ", tab_depth(5,depth), ps->data_offset ,name));
     442          23 :         if (charmode)
     443          23 :                 print_asc(5, (unsigned char*)data8s, len);
     444             :         else {
     445           0 :                 for (i = 0; i < len; i++)
     446           0 :                         DEBUGADD(5,("%02x ", data8s[i]));
     447             :         }
     448          23 :         DEBUGADD(5,("\n"));
     449             : 
     450          23 :         ps->data_offset += len;
     451             : 
     452          23 :         return True;
     453             : }

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