summaryrefslogtreecommitdiffstats
path: root/lib/fuzzing/fuzz_ndr_X.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/fuzzing/fuzz_ndr_X.c')
-rw-r--r--lib/fuzzing/fuzz_ndr_X.c337
1 files changed, 337 insertions, 0 deletions
diff --git a/lib/fuzzing/fuzz_ndr_X.c b/lib/fuzzing/fuzz_ndr_X.c
new file mode 100644
index 0000000..a3fb984
--- /dev/null
+++ b/lib/fuzzing/fuzz_ndr_X.c
@@ -0,0 +1,337 @@
+/*
+ Unix SMB/CIFS implementation.
+ Fuzzer for pidl-generated NDR pipes.
+ Copyright (C) Andrew Tridgell 2003
+ Copyright (C) Jelmer Vernooij 2006
+ Copyright (C) Andrew Bartlett 2019
+ Copyright (C) Catalyst.NET Ltd 2019
+
+ 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 "system/filesys.h"
+#include "system/locale.h"
+#include "librpc/ndr/libndr.h"
+#include "librpc/gen_ndr/ndr_dcerpc.h"
+#include "util/byteorder.h"
+#include "fuzzing/fuzzing.h"
+
+extern const struct ndr_interface_table FUZZ_PIPE_TABLE;
+
+#define FLAG_NDR64 4
+
+enum {
+ TYPE_STRUCT = 0,
+ TYPE_IN,
+ TYPE_OUT
+};
+
+/*
+ * header design (little endian):
+ *
+ * struct {
+ * uint16_t flags;
+ * uint16_t function_or_struct_no;
+ * };
+ */
+
+/*
+ * We want an even number here to ensure 4-byte alignment later
+ * not just for efficieny but because the fuzzers are known to guess
+ * that numbers will be 4-byte aligned
+ */
+#define HEADER_SIZE 4
+
+#define INVALID_FLAGS (~(FLAG_NDR64 | 3))
+
+static const struct ndr_interface_call *find_function(
+ const struct ndr_interface_table *p,
+ unsigned int function_no)
+{
+ if (function_no >= p->num_calls) {
+ return NULL;
+ }
+ return &p->calls[function_no];
+}
+
+/*
+ * Get a public structure by number and return it as if it were
+ * a function.
+ */
+static const struct ndr_interface_call *find_struct(
+ const struct ndr_interface_table *p,
+ unsigned int struct_no,
+ struct ndr_interface_call *out_buffer)
+{
+ const struct ndr_interface_public_struct *s = NULL;
+
+ if (struct_no >= p->num_public_structs) {
+ return NULL;
+ }
+
+ s = &p->public_structs[struct_no];
+
+ *out_buffer = (struct ndr_interface_call) {
+ .name = s->name,
+ .struct_size = s->struct_size,
+ .ndr_pull = s->ndr_pull,
+ .ndr_push = s->ndr_push,
+ .ndr_print = s->ndr_print
+ };
+ return out_buffer;
+}
+
+
+static NTSTATUS pull_chunks(struct ndr_pull *ndr_pull,
+ const struct ndr_interface_call_pipes *pipes)
+{
+ enum ndr_err_code ndr_err;
+ uint32_t i;
+
+ for (i=0; i < pipes->num_pipes; i++) {
+ while (true) {
+ void *saved_mem_ctx;
+ uint32_t *count;
+ void *c;
+
+ c = talloc_zero_size(ndr_pull, pipes->pipes[i].chunk_struct_size);
+ if (c == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+ /*
+ * Note: the first struct member is always
+ * 'uint32_t count;'
+ */
+ count = (uint32_t *)c;
+
+ saved_mem_ctx = ndr_pull->current_mem_ctx;
+ ndr_pull->current_mem_ctx = c;
+ ndr_err = pipes->pipes[i].ndr_pull(ndr_pull, NDR_SCALARS, c);
+ ndr_pull->current_mem_ctx = saved_mem_ctx;
+
+ if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+ talloc_free(c);
+ return ndr_map_error2ntstatus(ndr_err);
+ }
+ if (*count == 0) {
+ talloc_free(c);
+ break;
+ }
+ talloc_free(c);
+ }
+ }
+
+ return NT_STATUS_OK;
+}
+
+static void ndr_print_nothing(struct ndr_print *ndr, const char *format, ...)
+{
+ /*
+ * This is here so that we walk the tree but don't output anything.
+ * This helps find buggy ndr_print routines
+ */
+
+ /*
+ * TODO: consider calling snprinf() to find strings without NULL
+ * terminators (for example)
+ */
+}
+
+
+int LLVMFuzzerTestOneInput(uint8_t *data, size_t size) {
+ uint8_t type;
+ int pull_push_print_flags;
+ uint16_t fuzz_packet_flags, function;
+ TALLOC_CTX *mem_ctx = NULL;
+ uint32_t ndr_flags = 0;
+ struct ndr_push *ndr_push;
+ enum ndr_err_code ndr_err;
+ struct ndr_interface_call f_buffer;
+ const struct ndr_interface_call *f = NULL;
+ NTSTATUS status;
+
+/*
+ * This allows us to build binaries to fuzz just one target function
+ *
+ * In this mode the input becomes the 'stub data', there is no prefix.
+ *
+ * There is no NDR64 support in this mode at this time.
+ */
+#if defined(FUZZ_TYPE) && defined(FUZZ_FUNCTION)
+#undef HEADER_SIZE
+#define HEADER_SIZE 0
+ fuzz_packet_flags = 0;
+ type = FUZZ_TYPE;
+ function = FUZZ_FUNCTION;
+#else
+ if (size < HEADER_SIZE) {
+ /*
+ * the first few bytes decide what is being fuzzed --
+ * if they aren't all there we do nothing.
+ */
+ return 0;
+ }
+
+ fuzz_packet_flags = SVAL(data, 0);
+ if (fuzz_packet_flags & INVALID_FLAGS) {
+ return 0;
+ }
+
+ function = SVAL(data, 2);
+
+ type = fuzz_packet_flags & 3;
+
+#ifdef FUZZ_TYPE
+ /*
+ * Fuzz targets should have as small an interface as possible.
+ * This allows us to create 3 binaries for most pipes,
+ * TYPE_IN, TYPE_OUT and TYPE_STRUCT
+ *
+ * We keep the header format, and just exit early if it does
+ * not match.
+ */
+ if (type != FUZZ_TYPE) {
+ return 0;
+ }
+#endif
+#endif
+
+ switch (type) {
+ case TYPE_STRUCT:
+ pull_push_print_flags = NDR_SCALARS|NDR_BUFFERS;
+ f = find_struct(&FUZZ_PIPE_TABLE, function, &f_buffer);
+ break;
+ case TYPE_IN:
+ pull_push_print_flags = NDR_IN;
+ f = find_function(&FUZZ_PIPE_TABLE, function);
+ break;
+ case TYPE_OUT:
+ pull_push_print_flags = NDR_OUT;
+ f = find_function(&FUZZ_PIPE_TABLE, function);
+ break;
+ default:
+ return 0;
+ }
+
+ if (f == NULL) {
+ return 0;
+ }
+ if (fuzz_packet_flags & FLAG_NDR64) {
+ ndr_flags |= LIBNDR_FLAG_NDR64;
+ }
+
+ mem_ctx = talloc_init("ndrfuzz");
+
+ {
+ /*
+ * f->struct_size is well-controlled, it is essentially
+ * defined in the IDL
+ */
+ uint8_t st[f->struct_size];
+
+ DATA_BLOB blob = data_blob_const(data + HEADER_SIZE,
+ size - HEADER_SIZE);
+ struct ndr_pull *ndr_pull = ndr_pull_init_blob(&blob,
+ mem_ctx);
+
+ if (ndr_pull == NULL) {
+ perror("ndr_pull_init_blob");
+ TALLOC_FREE(mem_ctx);
+ return 0;
+ }
+
+ /*
+ * We must initialise the buffer (even if we would
+ * prefer not to for the sake of eg valgrind) as
+ * otherwise the special handler for 'out pointer with
+ * [size_is()] refers to in value with [ref]' fails to
+ * trigger
+ */
+ memset(st, '\0', sizeof(st));
+
+ ndr_pull->flags |= LIBNDR_FLAG_REF_ALLOC;
+ ndr_pull->global_max_recursion = 128;
+
+ if (type == TYPE_OUT) {
+ status = pull_chunks(ndr_pull,
+ &f->out_pipes);
+ if (!NT_STATUS_IS_OK(status)) {
+ TALLOC_FREE(mem_ctx);
+ return 0;
+ }
+ }
+
+ ndr_err = f->ndr_pull(ndr_pull,
+ pull_push_print_flags,
+ st);
+ if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+ TALLOC_FREE(mem_ctx);
+ return 0;
+ }
+
+ if (type == TYPE_IN) {
+ status = pull_chunks(ndr_pull,
+ &f->in_pipes);
+ if (!NT_STATUS_IS_OK(status)) {
+ TALLOC_FREE(mem_ctx);
+ return 0;
+ }
+ }
+
+ ndr_push = ndr_push_init_ctx(mem_ctx);
+ if (ndr_push == NULL) {
+ TALLOC_FREE(mem_ctx);
+ return 0;
+ }
+
+ ndr_push->flags |= ndr_flags;
+
+ /*
+ * Now push what was pulled, just in case we generated an
+ * invalid structure in memory, this should notice
+ */
+ ndr_err = f->ndr_push(ndr_push,
+ pull_push_print_flags,
+ st);
+ if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+ TALLOC_FREE(mem_ctx);
+ return 0;
+ }
+
+ {
+ struct ndr_print *ndr_print = talloc_zero(mem_ctx, struct ndr_print);
+ ndr_print->print = ndr_print_nothing;
+ ndr_print->depth = 1;
+
+ /*
+ * Finally print (to nowhere) the structure, this may also
+ * notice invalid memory
+ */
+ f->ndr_print(ndr_print,
+ f->name,
+ pull_push_print_flags,
+ st);
+ }
+ }
+ TALLOC_FREE(mem_ctx);
+
+ return 0;
+}
+
+
+int LLVMFuzzerInitialize(int *argc, char ***argv)
+{
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 21:16:05 +0000