add ability export PKCS7 to DER

resources/crypto.h

@@ -1,3 +1,5 @@
+void CRYPTO_free(void *addr);
+
 typedef struct crypto_ex_data_st CRYPTO_EX_DATA;
 struct crypto_ex_data_st {
   struct stack_st_void *sk;

resources/openssl.h

@@ -6,4 +6,4 @@ void OPENSSL_add_all_algorithms_conf(void);
 void OPENSSL_add_all_algorithms_noconf(void);
 
 void ERR_load_crypto_strings(void);
-void ERR_free_strings(void);
+void ERR_free_strings(void);

src/OpenSSL/BIO.php

@@ -196,33 +196,60 @@ class BIO extends CBackedObjectWithOwner
     const FLAG_RWS = self::FLAG_READ | self::FLAG_WRITE | self::FLAG_IO_SPECIAL;
     const FLAG_SHOULD_RETRY = 0x08;
 
-
-    public static function new()
+    /**
+     * Create new memory based BIO
+     *
+     * @return BIO
+     */
+    public static function new(): BIO
     {
         $ffi = OpenSSL::getFFI();
         $bio = $ffi->BIO_new($ffi->BIO_s_mem());
         return new BIO($ffi, $bio);
     }
 
-    public static function buffer(string $data)
+    /**
+     * Create new memory based BIO pre-filled with data
+     *
+     * @param string $data
+     * @return BIO
+     */
+    public static function buffer(string $data): BIO
     {
         $ffi = OpenSSL::getFFI();
         $bio = $ffi->BIO_new_mem_buf($data, strlen($data));
         return new BIO($ffi, $bio);
     }
 
-    public static function open($fileName, $flags)
+    /**
+     * Create new file BIO with given mode
+     *
+     * @param string $fileName which file to open
+     * @param string $mode mode to open file with see fopen(3)
+     * @return BIO
+     * @see fopen
+     */
+    public static function open(string $fileName, string $mode): BIO
     {
         $ffi = OpenSSL::getFFI();
-        $bio = $ffi->BIO_new_file($fileName, $flags);
+        $bio = $ffi->BIO_new_file($fileName, $mode);
         return new BIO($ffi, $bio);
     }
 
+    /**
+     * @inheritDoc
+     */
     protected function freeObject()
     {
         $this->ffi->BIO_free($this->cObj);
     }
 
+    /**
+     * Write given data to BIO, returns amount of bytes written
+     *
+     * @param string $data
+     * @return int
+     */
     function write(string $data): int
     {
         $len = $this->ffi->BIO_write($this->cObj, $data, strlen($data));
@@ -241,11 +268,22 @@ class BIO extends CBackedObjectWithOwner
         return $len;
     }
 
+    /**
+     * Get type of BIO, indicating if this is e.g. a file see BIO::TYPE_* constants
+     *
+     * @return int
+     */
     function getType(): int
     {
         return $this->ffi->BIO_method_type($this->cObj);
     }
 
+    /**
+     * Read from BIO
+     *
+     * @param int $chunkSize max amount of bytes to read in this operation
+     * @return string
+     */
     function read(int $chunkSize = 4096): string
     {
         $data = OpenSSL\C\Memory::new($chunkSize);
@@ -265,6 +303,11 @@ class BIO extends CBackedObjectWithOwner
         return $data->string($len);
     }
 
+    /**
+     * Get location in file pointer, this only works with file BIO's
+     *
+     * @return int
+     */
     function tell()
     {
         if (($this->getType() & self::TYPE_FILE) !== self::TYPE_FILE) {
@@ -280,7 +323,10 @@ class BIO extends CBackedObjectWithOwner
         return $pos;
     }
 
-    function reset()
+    /**
+     * Reset position in BIO
+     */
+    function reset(): void
     {
         $res = (int)$this->ctrl(self::CTRL_RESET, 0, null);
 
@@ -295,6 +341,11 @@ class BIO extends CBackedObjectWithOwner
         throw new RuntimeException("Failed to reset BIO");
     }
 
+    /**
+     * Seek in BIO, only works on file BIO's
+     *
+     * @param int $offset
+     */
     function seek(int $offset)
     {
         if (($this->getType() & self::TYPE_FILE) !== self::TYPE_FILE) {
@@ -308,12 +359,25 @@ class BIO extends CBackedObjectWithOwner
         }
     }
 
+    /**
+     * returns true if we're at EOF of this BIO
+     *
+     * @return bool
+     */
     function eof(): bool
     {
         return (int)$this->ctrl(self::CTRL_EOF, 0, null) === 1;
     }
 
-    function ctrl($prop, ?int $larg, $parg)
+    /**
+     * Send control command to BIO
+     *
+     * @param int $prop
+     * @param int $larg
+     * @param mixed $parg
+     * @return mixed
+     */
+    function ctrl(int $prop, int $larg = 0, $parg = null)
     {
         return $this->ffi->BIO_ctrl($this->cObj, $prop, $larg, $parg);
     }

src/OpenSSL/PKCS7.php

@@ -36,8 +36,20 @@ class PKCS7 extends OpenSSL\C\CBackedObjectWithOwner
         if (!in_array($type, [PKCS7::NID_DIGEST, self::NID_SIGNED, self::NID_SIGNED_AND_ENVELOPED])) {
             throw new \RuntimeException("Can only verify signed or digested data");
         }
+    }
 
+    public function toDER(): string
+    {
+        $buf = $this->ffi->new("uint8_t*");
+        $ptr = FFI::addr($buf);
+        $len = $this->ffi->i2d_PKCS7($this->cObj, $ptr);
+        if ($len < 0) {
+            throw new \RuntimeException("Failed to create DER from PKCS7 object");
+        }
 
+        $val = FFI::string($buf, $len);
+        $this->ffi->CRYPTO_free($buf);
+        return $val;
     }
 
     public function freeObject()
@@ -54,16 +66,16 @@ class PKCS7 extends OpenSSL\C\CBackedObjectWithOwner
 
     public static function loadFromDER(string $der): PKCS7
     {
-        $pkcs = static::new();
-        $pkcs->loadDER($der);
-        return $pkcs;
-    }
-
-    private function loadDER(string $der)
-    {
+        $ffi = OpenSSL::getFFI();
         $derLen = strlen($der);
         $mem = Memory::buffer($der);
-        $this->ffi->d2i_PKCS7(FFI::addr($this->cObj), $mem->pointer(), $derLen);
+        $res = $ffi->d2i_PKCS7(null, $mem->pointer(), $derLen);
+
+        if ($res === null) {
+            throw new \RuntimeException("Failed loading DER");
+        }
+
         $mem->freed();
+        return new static($ffi, $res);
     }
 }

tests/PKCS7Test.php

@@ -4,6 +4,7 @@ namespace Cijber\OpenSSL\Tests;
 
 use Cijber\OpenSSL\PKCS7;
 use PHPUnit\Framework\TestCase;
+use RuntimeException;
 
 class PKCS7Test extends TestCase
 {
@@ -14,9 +15,20 @@ class PKCS7Test extends TestCase
         unset($pkcs7);
     }
 
-    public function testLoadDER() {
+    public function testLoadDER()
+    {
         $der = file_get_contents(__DIR__ . "/data/pkcs7/1.RSA");
         $pkcs7 = PKCS7::loadFromDER($der);
+        $newDer = $pkcs7->toDER();
+        $this->assertEquals($der, $newDer);
         $this->assertEquals(PKCS7::NID_SIGNED, $pkcs7->getType());
     }
+
+    public function testLoadingGarbageDER()
+    {
+        $this->expectException(RuntimeException::class);
+        $this->expectExceptionMessage("Failed loading DER");
+
+        PKCS7::loadFromDER("blaat");
+    }
 }