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Diffstat (limited to 'source3/registry/reg_parse_prs.c')
| -rw-r--r-- | source3/registry/reg_parse_prs.c | 445 |
1 files changed, 445 insertions, 0 deletions
diff --git a/source3/registry/reg_parse_prs.c b/source3/registry/reg_parse_prs.c new file mode 100644 index 0000000..feec7cb --- /dev/null +++ b/source3/registry/reg_parse_prs.c @@ -0,0 +1,445 @@ +/* + Unix SMB/CIFS implementation. + Samba memory buffer functions + Copyright (C) Andrew Tridgell 1992-1997 + Copyright (C) Luke Kenneth Casson Leighton 1996-1997 + Copyright (C) Jeremy Allison 1999 + Copyright (C) Andrew Bartlett 2003. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "includes.h" +#include "reg_parse_prs.h" +#include "rpc_dce.h" + +#undef DBGC_CLASS +#define DBGC_CLASS DBGC_RPC_PARSE + +/******************************************************************* + Debug output for parsing info + + XXXX side-effect of this function is to increase the debug depth XXXX. + +********************************************************************/ + +void prs_debug(prs_struct *ps, int depth, const char *desc, const char *fn_name) +{ + DEBUG(5+depth, ("%s%06x %s %s\n", tab_depth(5+depth,depth), ps->data_offset, fn_name, desc)); +} + +/** + * Initialise an expandable parse structure. + * + * @param size Initial buffer size. If >0, a new buffer will be + * created with talloc(). + * + * @return False if allocation fails, otherwise True. + **/ + +bool prs_init(prs_struct *ps, uint32_t size, TALLOC_CTX *ctx, bool io) +{ + ZERO_STRUCTP(ps); + ps->io = io; + ps->bigendian_data = RPC_LITTLE_ENDIAN; + ps->align = RPC_PARSE_ALIGN; + ps->is_dynamic = False; + ps->data_offset = 0; + ps->buffer_size = 0; + ps->data_p = NULL; + ps->mem_ctx = ctx; + + if (size != 0) { + ps->buffer_size = size; + ps->data_p = (char *)talloc_zero_size(ps->mem_ctx, size); + if(ps->data_p == NULL) { + DEBUG(0,("prs_init: talloc fail for %u bytes.\n", (unsigned int)size)); + return False; + } + ps->is_dynamic = True; /* We own this memory. */ + } else if (MARSHALLING(ps)) { + /* If size is zero and we're marshalling we should allocate memory on demand. */ + ps->is_dynamic = True; + } + + return True; +} + +/******************************************************************* + Delete the memory in a parse structure - if we own it. + + NOTE: Contrary to the somewhat confusing naming, this function is not + intended for freeing memory allocated by prs_alloc_mem(). + That memory is also attached to the talloc context given by + ps->mem_ctx, but is only freed when that talloc context is + freed. prs_mem_free() is used to delete "dynamic" memory + allocated in marshalling/unmarshalling. + ********************************************************************/ + +void prs_mem_free(prs_struct *ps) +{ + if(ps->is_dynamic) { + TALLOC_FREE(ps->data_p); + } + ps->is_dynamic = False; + ps->buffer_size = 0; + ps->data_offset = 0; +} + +/******************************************************************* + Allocate memory when unmarshalling... Always zero clears. + ********************************************************************/ + +#if defined(PARANOID_MALLOC_CHECKER) +char *prs_alloc_mem_(prs_struct *ps, size_t size, unsigned int count) +#else +char *prs_alloc_mem(prs_struct *ps, size_t size, unsigned int count) +#endif +{ + char *ret = NULL; + + if (size && count) { + /* We can't call the type-safe version here. */ + ret = (char *)_talloc_zero_array(ps->mem_ctx, size, count, + "parse_prs"); + } + return ret; +} + +/******************************************************************* + Return the current talloc context we're using. + ********************************************************************/ + +TALLOC_CTX *prs_get_mem_context(prs_struct *ps) +{ + return ps->mem_ctx; +} + +/******************************************************************* + Attempt, if needed, to grow a data buffer. + Also depends on the data stream mode (io). + ********************************************************************/ + +bool prs_grow(prs_struct *ps, uint32_t extra_space) +{ + uint32_t new_size; + + ps->grow_size = MAX(ps->grow_size, ps->data_offset + extra_space); + + if(ps->data_offset + extra_space <= ps->buffer_size) + return True; + + /* + * We cannot grow the buffer if we're not reading + * into the prs_struct, or if we don't own the memory. + */ + + if(UNMARSHALLING(ps) || !ps->is_dynamic) { + DEBUG(0,("prs_grow: Buffer overflow - unable to expand buffer by %u bytes.\n", + (unsigned int)extra_space)); + return False; + } + + /* + * Decide how much extra space we really need. + */ + + extra_space -= (ps->buffer_size - ps->data_offset); + if(ps->buffer_size == 0) { + + /* + * Start with 128 bytes (arbitrary value), enough for small rpc + * requests + */ + new_size = MAX(128, extra_space); + + ps->data_p = (char *)talloc_zero_size(ps->mem_ctx, new_size); + if(ps->data_p == NULL) { + DEBUG(0,("prs_grow: talloc failure for size %u.\n", (unsigned int)new_size)); + return False; + } + } else { + /* + * If the current buffer size is bigger than the space needed, + * just double it, else add extra_space. Always keep 64 bytes + * more, so that after we added a large blob we don't have to + * realloc immediately again. + */ + new_size = MAX(ps->buffer_size*2, + ps->buffer_size + extra_space + 64); + + ps->data_p = talloc_realloc(ps->mem_ctx, + ps->data_p, + char, + new_size); + if (ps->data_p == NULL) { + DEBUG(0,("prs_grow: Realloc failure for size %u.\n", + (unsigned int)new_size)); + return False; + } + + memset(&ps->data_p[ps->buffer_size], '\0', (size_t)(new_size - ps->buffer_size)); + } + ps->buffer_size = new_size; + + return True; +} + +/******************************************************************* + Get the data pointer (external interface). +********************************************************************/ + +char *prs_data_p(prs_struct *ps) +{ + return ps->data_p; +} + +/******************************************************************* + Get the current data size (external interface). + ********************************************************************/ + +uint32_t prs_data_size(prs_struct *ps) +{ + return ps->buffer_size; +} + +/******************************************************************* + Fetch the current offset (external interface). + ********************************************************************/ + +uint32_t prs_offset(prs_struct *ps) +{ + return ps->data_offset; +} + +/******************************************************************* + Set the current offset (external interface). + ********************************************************************/ + +bool prs_set_offset(prs_struct *ps, uint32_t offset) +{ + if ((offset > ps->data_offset) + && !prs_grow(ps, offset - ps->data_offset)) { + return False; + } + + ps->data_offset = offset; + return True; +} + +/******************************************************************* + Append the data from a buffer into a parse_struct. + ********************************************************************/ + +bool prs_copy_data_in(prs_struct *dst, const char *src, uint32_t len) +{ + if (len == 0) + return True; + + if(!prs_grow(dst, len)) + return False; + + memcpy(&dst->data_p[dst->data_offset], src, (size_t)len); + dst->data_offset += len; + + return True; +} + +/******************************************************************* + Align a the data_len to a multiple of align bytes - filling with + zeros. + ********************************************************************/ + +bool prs_align(prs_struct *ps) +{ + uint32_t mod = ps->data_offset & (ps->align-1); + + if (ps->align != 0 && mod != 0) { + uint32_t extra_space = (ps->align - mod); + if(!prs_grow(ps, extra_space)) + return False; + memset(&ps->data_p[ps->data_offset], '\0', (size_t)extra_space); + ps->data_offset += extra_space; + } + + return True; +} + +/****************************************************************** + Align on a 8 byte boundary + *****************************************************************/ + +bool prs_align_uint64(prs_struct *ps) +{ + bool ret; + uint8_t old_align = ps->align; + + ps->align = 8; + ret = prs_align(ps); + ps->align = old_align; + + return ret; +} + +/******************************************************************* + Ensure we can read/write to a given offset. + ********************************************************************/ + +char *prs_mem_get(prs_struct *ps, uint32_t extra_size) +{ + if(UNMARSHALLING(ps)) { + /* + * If reading, ensure that we can read the requested size item. + */ + if (ps->data_offset + extra_size > ps->buffer_size) { + DEBUG(0,("prs_mem_get: reading data of size %u would overrun " + "buffer by %u bytes.\n", + (unsigned int)extra_size, + (unsigned int)(ps->data_offset + extra_size - ps->buffer_size) )); + return NULL; + } + } else { + /* + * Writing - grow the buffer if needed. + */ + if(!prs_grow(ps, extra_size)) + return NULL; + } + return &ps->data_p[ps->data_offset]; +} + +/******************************************************************* + Change the struct type. + ********************************************************************/ + +void prs_switch_type(prs_struct *ps, bool io) +{ + if ((ps->io ^ io) == True) + ps->io=io; +} + +/******************************************************************* + Stream a uint16. + ********************************************************************/ + +bool prs_uint16(const char *name, prs_struct *ps, int depth, uint16_t *data16) +{ + char *q = prs_mem_get(ps, sizeof(uint16_t)); + if (q == NULL) + return False; + + if (UNMARSHALLING(ps)) { + if (ps->bigendian_data) + *data16 = RSVAL(q,0); + else + *data16 = SVAL(q,0); + } else { + if (ps->bigendian_data) + RSSVAL(q,0,*data16); + else + SSVAL(q,0,*data16); + } + + DEBUGADD(5,("%s%04x %s: %04x\n", tab_depth(5,depth), ps->data_offset, name, *data16)); + + ps->data_offset += sizeof(uint16_t); + + return True; +} + +/******************************************************************* + Stream a uint32. + ********************************************************************/ + +bool prs_uint32(const char *name, prs_struct *ps, int depth, uint32_t *data32) +{ + char *q = prs_mem_get(ps, sizeof(uint32_t)); + if (q == NULL) + return False; + + if (UNMARSHALLING(ps)) { + if (ps->bigendian_data) + *data32 = RIVAL(q,0); + else + *data32 = IVAL(q,0); + } else { + if (ps->bigendian_data) + RSIVAL(q,0,*data32); + else + SIVAL(q,0,*data32); + } + + DEBUGADD(5,("%s%04x %s: %08x\n", tab_depth(5,depth), ps->data_offset, name, *data32)); + + ps->data_offset += sizeof(uint32_t); + + return True; +} + +/******************************************************************* + Stream a uint64_struct + ********************************************************************/ +bool prs_uint64(const char *name, prs_struct *ps, int depth, uint64_t *data64) +{ + if (UNMARSHALLING(ps)) { + uint32_t high, low; + + if (!prs_uint32(name, ps, depth+1, &low)) + return False; + + if (!prs_uint32(name, ps, depth+1, &high)) + return False; + + *data64 = ((uint64_t)high << 32) + low; + + return True; + } else { + uint32_t high = (*data64) >> 32, low = (*data64) & 0xFFFFFFFF; + return prs_uint32(name, ps, depth+1, &low) && + prs_uint32(name, ps, depth+1, &high); + } +} + +/****************************************************************** + Stream an array of uint8s. Length is number of uint8s. + ********************************************************************/ + +bool prs_uint8s(bool charmode, const char *name, prs_struct *ps, int depth, uint8_t *data8s, int len) +{ + int i; + char *q = prs_mem_get(ps, len); + if (q == NULL) + return False; + + if (UNMARSHALLING(ps)) { + for (i = 0; i < len; i++) + data8s[i] = CVAL(q,i); + } else { + for (i = 0; i < len; i++) + SCVAL(q, i, data8s[i]); + } + + DEBUGADD(5,("%s%04x %s: ", tab_depth(5,depth), ps->data_offset ,name)); + if (charmode) + print_asc(5, (unsigned char*)data8s, len); + else { + for (i = 0; i < len; i++) + DEBUGADD(5,("%02x ", data8s[i])); + } + DEBUGADD(5,("\n")); + + ps->data_offset += len; + + return True; +} |