/* Unix SMB/CIFS implementation. libndr interface Copyright (C) Andrew Tridgell 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 2 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, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* this provides the core routines for NDR parsing functions see http://www.opengroup.org/onlinepubs/9629399/chap14.htm for details of NDR encoding rules */ #include "includes.h" #define NDR_BASE_MARSHALL_SIZE 1024 /* work out the number of bytes needed to align on a n byte boundary */ size_t ndr_align_size(uint32_t offset, size_t n) { if ((offset & (n-1)) == 0) return 0; return n - (offset & (n-1)); } /* initialise a ndr parse structure from a data blob */ struct ndr_pull *ndr_pull_init_blob(const DATA_BLOB *blob, TALLOC_CTX *mem_ctx) { struct ndr_pull *ndr; ndr = talloc(mem_ctx, sizeof(*ndr)); if (!ndr) return NULL; ndr->flags = 0; ndr->data = blob->data; ndr->data_size = blob->length; ndr->offset = 0; ndr->ptr_count = 0; ndr->relative_list = NULL; return ndr; } /* create an ndr sub-context based on an existing context. The new context starts at the current offset, with the given size limit */ NTSTATUS ndr_pull_subcontext(struct ndr_pull *ndr, struct ndr_pull *ndr2, uint32_t size) { NDR_PULL_NEED_BYTES(ndr, size); *ndr2 = *ndr; ndr2->data += ndr2->offset; ndr2->offset = 0; ndr2->data_size = size; ndr2->flags = ndr->flags; return NT_STATUS_OK; } /* advance by 'size' bytes */ NTSTATUS ndr_pull_advance(struct ndr_pull *ndr, uint32_t size) { ndr->offset += size; if (ndr->offset > ndr->data_size) { return ndr_pull_error(ndr, NDR_ERR_BUFSIZE, "ndr_pull_advance by %u failed", size); } return NT_STATUS_OK; } /* set the parse offset to 'ofs' */ NTSTATUS ndr_pull_set_offset(struct ndr_pull *ndr, uint32_t ofs) { ndr->offset = ofs; if (ndr->offset > ndr->data_size) { return ndr_pull_error(ndr, NDR_ERR_BUFSIZE, "ndr_pull_set_offset %u failed", ofs); } return NT_STATUS_OK; } /* save the offset/size of the current ndr state */ void ndr_pull_save(struct ndr_pull *ndr, struct ndr_pull_save *save) { save->offset = ndr->offset; save->data_size = ndr->data_size; } /* restore the size/offset of a ndr structure */ void ndr_pull_restore(struct ndr_pull *ndr, struct ndr_pull_save *save) { ndr->offset = save->offset; ndr->data_size = save->data_size; } /* create a ndr_push structure, ready for some marshalling */ struct ndr_push *ndr_push_init_ctx(TALLOC_CTX *mem_ctx) { struct ndr_push *ndr; ndr = talloc(mem_ctx, sizeof(*ndr)); if (!ndr) { return NULL; } ndr->flags = 0; ndr->alloc_size = NDR_BASE_MARSHALL_SIZE; ndr->data = talloc(ndr, ndr->alloc_size); if (!ndr->data) { return NULL; } ndr->offset = 0; ndr->ptr_count = 0; ndr->relative_list = NULL; return ndr; } /* create a ndr_push structure, ready for some marshalling */ struct ndr_push *ndr_push_init(void) { struct ndr_push *ndr; TALLOC_CTX *mem_ctx = talloc_init("ndr_push_init"); if (!mem_ctx) return NULL; ndr = ndr_push_init_ctx(mem_ctx); if (!ndr) { talloc_destroy(mem_ctx); } return ndr; } /* free a ndr_push structure */ void ndr_push_free(struct ndr_push *ndr) { talloc_destroy(ndr); } /* return a DATA_BLOB structure for the current ndr_push marshalled data */ DATA_BLOB ndr_push_blob(struct ndr_push *ndr) { DATA_BLOB blob; blob.data = ndr->data; blob.length = ndr->offset; return blob; } /* expand the available space in the buffer to 'size' */ NTSTATUS ndr_push_expand(struct ndr_push *ndr, uint32_t size) { if (ndr->alloc_size >= size) { return NT_STATUS_OK; } ndr->alloc_size += NDR_BASE_MARSHALL_SIZE; if (size > ndr->alloc_size) { ndr->alloc_size = size; } ndr->data = talloc_realloc(ndr->data, ndr->alloc_size); if (!ndr->data) { return ndr_push_error(ndr, NDR_ERR_ALLOC, "Failed to push_expand to %u", ndr->alloc_size); } return NT_STATUS_OK; } /* set the push offset to 'ofs' */ NTSTATUS ndr_push_set_offset(struct ndr_push *ndr, uint32_t ofs) { NDR_CHECK(ndr_push_expand(ndr, ofs)); ndr->offset = ofs; return NT_STATUS_OK; } /* push a generic array */ NTSTATUS ndr_push_array(struct ndr_push *ndr, int ndr_flags, void *base, size_t elsize, uint32_t count, NTSTATUS (*push_fn)(struct ndr_push *, int, void *)) { int i; char *p = base; if (!(ndr_flags & NDR_SCALARS)) goto buffers; for (i=0;iprint(ndr, "%s: ARRAY(%d)", name, count); ndr->depth++; for (i=0;idepth--; } void ndr_print_debug_helper(struct ndr_print *ndr, const char *format, ...) _PRINTF_ATTRIBUTE(2,3) { va_list ap; char *s = NULL; int i; va_start(ap, format); vasprintf(&s, format, ap); va_end(ap); for (i=0;idepth;i++) { DEBUG(0,(" ")); } DEBUG(0,("%s\n", s)); free(s); } /* a useful helper function for printing idl structures via DEBUG() */ void ndr_print_debug(void (*fn)(struct ndr_print *, const char *, void *), const char *name, void *ptr) { struct ndr_print *ndr; ndr = talloc_p(NULL, struct ndr_print); if (!ndr) return; ndr->print = ndr_print_debug_helper; ndr->depth = 1; ndr->flags = 0; fn(ndr, name, ptr); talloc_free(ndr); } /* a useful helper function for printing idl unions via DEBUG() */ void ndr_print_union_debug(void (*fn)(struct ndr_print *, const char *, uint32_t, void *), const char *name, uint32_t level, void *ptr) { struct ndr_print *ndr; ndr = talloc_p(NULL, struct ndr_print); if (!ndr) return; ndr->print = ndr_print_debug_helper; ndr->depth = 1; ndr->flags = 0; fn(ndr, name, level, ptr); talloc_free(ndr); } /* a useful helper function for printing idl function calls via DEBUG() */ void ndr_print_function_debug(void (*fn)(struct ndr_print *, const char *, int , void *), const char *name, int flags, void *ptr) { struct ndr_print *ndr; ndr = talloc_p(NULL, struct ndr_print); if (!ndr) return; ndr->print = ndr_print_debug_helper; ndr->depth = 1; ndr->flags = 0; fn(ndr, name, flags, ptr); talloc_free(ndr); } static NTSTATUS ndr_map_error(enum ndr_err_code err) { switch (err) { case NDR_ERR_BUFSIZE: return NT_STATUS_BUFFER_TOO_SMALL; case NDR_ERR_ALLOC: return NT_STATUS_NO_MEMORY; } /* we should all error codes to different status codes */ return NT_STATUS_INVALID_PARAMETER; } /* return and possibly log an NDR error */ NTSTATUS ndr_pull_error(struct ndr_pull *ndr, enum ndr_err_code err, const char *format, ...) _PRINTF_ATTRIBUTE(3,4) { char *s=NULL; va_list ap; va_start(ap, format); vasprintf(&s, format, ap); va_end(ap); DEBUG(3,("ndr_pull_error(%u): %s\n", err, s)); free(s); return ndr_map_error(err); } /* return and possibly log an NDR error */ NTSTATUS ndr_push_error(struct ndr_push *ndr, enum ndr_err_code err, const char *format, ...) _PRINTF_ATTRIBUTE(3,4) { char *s=NULL; va_list ap; va_start(ap, format); vasprintf(&s, format, ap); va_end(ap); DEBUG(3,("ndr_push_error(%u): %s\n", err, s)); free(s); return ndr_map_error(err); } /* handle subcontext buffers, which in midl land are user-marshalled, but we use magic in pidl to make them easier to cope with */ static NTSTATUS ndr_pull_subcontext_header(struct ndr_pull *ndr, size_t sub_size, struct ndr_pull *ndr2) { switch (sub_size) { case 0: { uint32_t size = ndr->data_size - ndr->offset; if (size == 0) return NT_STATUS_OK; NDR_CHECK(ndr_pull_subcontext(ndr, ndr2, size)); break; } case 2: { uint16_t size; NDR_CHECK(ndr_pull_uint16(ndr, &size)); if (size == 0) return NT_STATUS_OK; NDR_CHECK(ndr_pull_subcontext(ndr, ndr2, size)); break; } case 4: { uint32_t size; NDR_CHECK(ndr_pull_uint32(ndr, &size)); if (size == 0) return NT_STATUS_OK; NDR_CHECK(ndr_pull_subcontext(ndr, ndr2, size)); break; } default: return ndr_pull_error(ndr, NDR_ERR_SUBCONTEXT, "Bad subcontext size %d", sub_size); } return NT_STATUS_OK; } /* handle subcontext buffers, which in midl land are user-marshalled, but we use magic in pidl to make them easier to cope with */ NTSTATUS ndr_pull_subcontext_fn(struct ndr_pull *ndr, size_t sub_size, void *base, NTSTATUS (*fn)(struct ndr_pull *, void *)) { struct ndr_pull *ndr2; NDR_ALLOC(ndr, ndr2); NDR_CHECK(ndr_pull_subcontext_header(ndr, sub_size, ndr2)); NDR_CHECK(fn(ndr2, base)); if (sub_size) { NDR_CHECK(ndr_pull_advance(ndr, ndr2->data_size)); } else { NDR_CHECK(ndr_pull_advance(ndr, ndr2->offset)); } return NT_STATUS_OK; } NTSTATUS ndr_pull_subcontext_flags_fn(struct ndr_pull *ndr, size_t sub_size, void *base, NTSTATUS (*fn)(struct ndr_pull *, int , void *)) { struct ndr_pull *ndr2; NDR_ALLOC(ndr, ndr2); NDR_CHECK(ndr_pull_subcontext_header(ndr, sub_size, ndr2)); NDR_CHECK(fn(ndr2, NDR_SCALARS|NDR_BUFFERS, base)); if (sub_size) { NDR_CHECK(ndr_pull_advance(ndr, ndr2->data_size)); } else { NDR_CHECK(ndr_pull_advance(ndr, ndr2->offset)); } return NT_STATUS_OK; } NTSTATUS ndr_pull_subcontext_union_fn(struct ndr_pull *ndr, size_t sub_size, uint32_t level, void *base, NTSTATUS (*fn)(struct ndr_pull *, int , uint32_t , void *)) { struct ndr_pull *ndr2; NDR_ALLOC(ndr, ndr2); NDR_CHECK(ndr_pull_subcontext_header(ndr, sub_size, ndr2)); NDR_CHECK(fn(ndr2, NDR_SCALARS|NDR_BUFFERS, level, base)); if (sub_size) { NDR_CHECK(ndr_pull_advance(ndr, ndr2->data_size)); } else { NDR_CHECK(ndr_pull_advance(ndr, ndr2->offset)); } return NT_STATUS_OK; } /* push a subcontext header */ static NTSTATUS ndr_push_subcontext_header(struct ndr_push *ndr, size_t sub_size, struct ndr_push *ndr2) { switch (sub_size) { case 0: break; case 2: NDR_CHECK(ndr_push_uint16(ndr, ndr2->offset)); break; case 4: NDR_CHECK(ndr_push_uint32(ndr, ndr2->offset)); break; default: return ndr_push_error(ndr, NDR_ERR_SUBCONTEXT, "Bad subcontext size %d", sub_size); } return NT_STATUS_OK; } /* handle subcontext buffers, which in midl land are user-marshalled, but we use magic in pidl to make them easier to cope with */ NTSTATUS ndr_push_subcontext_fn(struct ndr_push *ndr, size_t sub_size, void *base, NTSTATUS (*fn)(struct ndr_push *, void *)) { struct ndr_push *ndr2; ndr2 = ndr_push_init_ctx(ndr); if (!ndr2) return NT_STATUS_NO_MEMORY; ndr2->flags = ndr->flags; NDR_CHECK(fn(ndr2, base)); NDR_CHECK(ndr_push_subcontext_header(ndr, sub_size, ndr2)); NDR_CHECK(ndr_push_bytes(ndr, ndr2->data, ndr2->offset)); return NT_STATUS_OK; } /* handle subcontext buffers for function that take a flags arg */ NTSTATUS ndr_push_subcontext_flags_fn(struct ndr_push *ndr, size_t sub_size, void *base, NTSTATUS (*fn)(struct ndr_push *, int, void *)) { struct ndr_push *ndr2; ndr2 = ndr_push_init_ctx(ndr); if (!ndr2) return NT_STATUS_NO_MEMORY; ndr2->flags = ndr->flags; NDR_CHECK(fn(ndr2, NDR_SCALARS|NDR_BUFFERS, base)); NDR_CHECK(ndr_push_subcontext_header(ndr, sub_size, ndr2)); NDR_CHECK(ndr_push_bytes(ndr, ndr2->data, ndr2->offset)); return NT_STATUS_OK; } /* handle subcontext buffers for function that take a union */ NTSTATUS ndr_push_subcontext_union_fn(struct ndr_push *ndr, size_t sub_size, uint32_t level, void *base, NTSTATUS (*fn)(struct ndr_push *, int, uint32_t, void *)) { struct ndr_push *ndr2; ndr2 = ndr_push_init_ctx(ndr); if (!ndr2) return NT_STATUS_NO_MEMORY; ndr2->flags = ndr->flags; NDR_CHECK(fn(ndr2, NDR_SCALARS|NDR_BUFFERS, level, base)); NDR_CHECK(ndr_push_subcontext_header(ndr, sub_size, ndr2)); NDR_CHECK(ndr_push_bytes(ndr, ndr2->data, ndr2->offset)); return NT_STATUS_OK; } /* mark the start of a structure */ NTSTATUS ndr_pull_struct_start(struct ndr_pull *ndr) { return NT_STATUS_OK; } /* mark the end of a structure */ void ndr_pull_struct_end(struct ndr_pull *ndr) { } /* mark the start of a structure */ NTSTATUS ndr_push_struct_start(struct ndr_push *ndr) { return NT_STATUS_OK; } /* mark the end of a structure */ void ndr_push_struct_end(struct ndr_push *ndr) { } /* pull a relative structure */ NTSTATUS ndr_pull_relative(struct ndr_pull *ndr, const void **buf, size_t size, NTSTATUS (*fn)(struct ndr_pull *, int ndr_flags, void *)) { struct ndr_pull *ndr2; uint32_t ofs; struct ndr_pull_save save; void *p; NDR_ALLOC(ndr, ndr2); NDR_CHECK(ndr_pull_uint32(ndr, &ofs)); if (ofs == 0) { (*buf) = NULL; return NT_STATUS_OK; } ndr_pull_save(ndr, &save); /* the old way of handling relative pointers appears to be wrong, and there doesn't seem to be anything relying on it, but I am keeping the code around in case I missed a critical use for it (tridge, august 2004) */ NDR_CHECK(ndr_pull_set_offset(ndr, ofs)); NDR_CHECK(ndr_pull_subcontext(ndr, ndr2, ndr->data_size - ndr->offset)); /* strings must be allocated by the backend functions */ if (ndr->flags & LIBNDR_STRING_FLAGS) { NDR_CHECK(fn(ndr2, NDR_SCALARS|NDR_BUFFERS, &p)); } else { NDR_ALLOC_SIZE(ndr, p, size); NDR_CHECK(fn(ndr2, NDR_SCALARS|NDR_BUFFERS, p)); } (*buf) = p; ndr_pull_restore(ndr, &save); talloc_free(ndr2); return NT_STATUS_OK; } /* store a token in the ndr context, for later retrieval */ static NTSTATUS ndr_token_store(TALLOC_CTX *mem_ctx, struct ndr_token_list **list, const void *key, uint32_t value) { struct ndr_token_list *tok; tok = talloc_p(mem_ctx, struct ndr_token_list); if (tok == NULL) { return NT_STATUS_NO_MEMORY; } tok->key = key; tok->value = value; DLIST_ADD((*list), tok); return NT_STATUS_OK; } /* retrieve a token from a ndr context */ static uint32_t ndr_token_retrieve(struct ndr_token_list **list, const void *key) { struct ndr_token_list *tok; for (tok=*list;tok;tok=tok->next) { if (tok->key == key) { DLIST_REMOVE((*list), tok); return tok->value; } } return 0; } /* pull a relative object - stage1 called during SCALARS processing */ NTSTATUS ndr_pull_relative1(struct ndr_pull *ndr, const void *p, uint32_t rel_offset) { return ndr_token_store(ndr, &ndr->relative_list, p, rel_offset); } /* pull a relative object - stage2 called during BUFFERS processing */ NTSTATUS ndr_pull_relative2(struct ndr_pull *ndr, const void *p) { uint32_t rel_offset; rel_offset = ndr_token_retrieve(&ndr->relative_list, p); if (rel_offset == 0) { return NT_STATUS_INTERNAL_ERROR; } return ndr_pull_set_offset(ndr, rel_offset); } /* push a relative object - stage1 this is called during SCALARS processing */ NTSTATUS ndr_push_relative1(struct ndr_push *ndr, const void *p) { if (p == NULL) { NDR_CHECK(ndr_push_uint32(ndr, 0)); return NT_STATUS_OK; } NDR_CHECK(ndr_push_align(ndr, 4)); NDR_CHECK(ndr_token_store(ndr, &ndr->relative_list, p, ndr->offset)); return ndr_push_uint32(ndr, 0xFFFFFFFF); } /* push a relative object - stage2 this is called during buffers processing */ NTSTATUS ndr_push_relative2(struct ndr_push *ndr, const void *p) { struct ndr_push_save save; if (p == NULL) { return NT_STATUS_OK; } NDR_CHECK(ndr_push_align(ndr, 4)); ndr_push_save(ndr, &save); ndr->offset = ndr_token_retrieve(&ndr->relative_list, p); if (ndr->offset == 0) { return NT_STATUS_INTERNAL_ERROR; } NDR_CHECK(ndr_push_uint32(ndr, save.offset)); ndr_push_restore(ndr, &save); return NT_STATUS_OK; } /* pull a union from a blob using NDR */ NTSTATUS ndr_pull_union_blob(DATA_BLOB *blob, TALLOC_CTX *mem_ctx, uint32_t level, void *p, NTSTATUS (*fn)(struct ndr_pull *, int ndr_flags, uint32_t, void *)) { struct ndr_pull *ndr; ndr = ndr_pull_init_blob(blob, mem_ctx); if (!ndr) { return NT_STATUS_NO_MEMORY; } return fn(ndr, NDR_SCALARS|NDR_BUFFERS, level, p); } /* pull a struct from a blob using NDR */ NTSTATUS ndr_pull_struct_blob(const DATA_BLOB *blob, TALLOC_CTX *mem_ctx, void *p, NTSTATUS (*fn)(struct ndr_pull *, int , void *)) { struct ndr_pull *ndr; ndr = ndr_pull_init_blob(blob, mem_ctx); if (!ndr) { return NT_STATUS_NO_MEMORY; } return fn(ndr, NDR_SCALARS|NDR_BUFFERS, p); } /* push a struct to a blob using NDR */ NTSTATUS ndr_push_struct_blob(DATA_BLOB *blob, TALLOC_CTX *mem_ctx, void *p, NTSTATUS (*fn)(struct ndr_push *, int , void *)) { NTSTATUS status; struct ndr_push *ndr; ndr = ndr_push_init_ctx(mem_ctx); if (!ndr) { return NT_STATUS_NO_MEMORY; } status = fn(ndr, NDR_SCALARS|NDR_BUFFERS, p); if (!NT_STATUS_IS_OK(status)) { return status; } *blob = ndr_push_blob(ndr); return NT_STATUS_OK; }