From 106a0afc5a8819d6f7fc450c66caa5919681cdd5 Mon Sep 17 00:00:00 2001
From: Nayna Jain <nayna@linux.ibm.com>
Date: Tue, 3 Nov 2020 21:07:21 +0000
Subject: [PATCH] pkcs7: provide fuzz harness

This allows for pkcs7 fuzz testing with OSS-Fuzz.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
---
 programs/fuzz/.gitignore         |  1 +
 programs/fuzz/CMakeLists.txt     |  1 +
 programs/fuzz/fuzz_pkcs7.c       | 19 +++++++++++++++++++
 programs/fuzz/fuzz_pkcs7.options |  2 ++
 4 files changed, 23 insertions(+)
 create mode 100644 programs/fuzz/fuzz_pkcs7.c
 create mode 100644 programs/fuzz/fuzz_pkcs7.options

diff --git a/programs/fuzz/.gitignore b/programs/fuzz/.gitignore
index 5dc096055..34e3ed088 100644
--- a/programs/fuzz/.gitignore
+++ b/programs/fuzz/.gitignore
@@ -1,6 +1,7 @@
 fuzz_client
 fuzz_dtlsclient
 fuzz_dtlsserver
+fuzz_pkcs7
 fuzz_privkey
 fuzz_pubkey
 fuzz_server
diff --git a/programs/fuzz/CMakeLists.txt b/programs/fuzz/CMakeLists.txt
index c7fcd356b..7747744cd 100644
--- a/programs/fuzz/CMakeLists.txt
+++ b/programs/fuzz/CMakeLists.txt
@@ -12,6 +12,7 @@ set(executables_no_common_c
     fuzz_x509crl
     fuzz_x509crt
     fuzz_x509csr
+    fuzz_pkcs7
 )
 
 set(executables_with_common_c
diff --git a/programs/fuzz/fuzz_pkcs7.c b/programs/fuzz/fuzz_pkcs7.c
new file mode 100644
index 000000000..960007d7a
--- /dev/null
+++ b/programs/fuzz/fuzz_pkcs7.c
@@ -0,0 +1,19 @@
+#include <stdint.h>
+#include "mbedtls/pkcs7.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#ifdef MBEDTLS_PKCS7_C
+    mbedtls_pkcs7 pkcs7;
+
+    mbedtls_pkcs7_init( &pkcs7 );
+
+    mbedtls_pkcs7_parse_der( &pkcs7, Data, Size );
+
+    mbedtls_pkcs7_free( &pkcs7 );
+#else
+    (void) Data;
+    (void) Size;
+#endif
+
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_pkcs7.options b/programs/fuzz/fuzz_pkcs7.options
new file mode 100644
index 000000000..0824b19fa
--- /dev/null
+++ b/programs/fuzz/fuzz_pkcs7.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65535