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FFI can't resolve C symbols from SSL library.

Posted: Tue Jun 27, 2017 4:09 pm
by Ranguna259
I downloaded a precompiled openSSL dll and tested it with luajit 2.1.0-beta2 with the following code copied from stackoverflow:

Code: Select all

local ffi = require "ffi"
local ssl = ffi.load "ssl"

ffi.cdef[[
  typedef struct bio_st BIO;
  typedef struct bio_method_st BIO_METHOD;
  BIO *BIO_new(BIO_METHOD *type);
  BIO *BIO_new_mem_buf(void *buf, int len);
  typedef struct evp_pkey_ctx_st EVP_PKEY_CTX;
  typedef struct evp_pkey_st EVP_PKEY;
  typedef struct engine_st ENGINE;
  EVP_PKEY *EVP_PKEY_new(void);
  void EVP_PKEY_free(EVP_PKEY *key);
  typedef struct rsa_st RSA;
  typedef int pem_password_cb(char *buf, int size, int rwflag, void *userdata);
  RSA * PEM_read_bio_RSAPrivateKey(BIO *bp, RSA **rsa, pem_password_cb *cb, void *u);
  int EVP_PKEY_set1_RSA(EVP_PKEY *pkey,RSA *key);
  EVP_PKEY_CTX *EVP_PKEY_CTX_new(EVP_PKEY *pkey, ENGINE *e);
  int EVP_PKEY_CTX_ctrl(EVP_PKEY_CTX *ctx, int keytype, int optype, int cmd, int p1, void *p2);
  typedef struct x509_st X509;
  X509 *PEM_read_bio_X509(BIO *bp, X509 **x, pem_password_cb *cb, void *u);
  EVP_PKEY * X509_get_pubkey(X509 *x);
  void X509_free(X509 *a);
  int EVP_PKEY_encrypt_init(EVP_PKEY_CTX *ctx);
  int EVP_PKEY_encrypt(EVP_PKEY_CTX *ctx, unsigned char *out, size_t *outlen, const unsigned char *in, size_t inlen);
  int EVP_PKEY_decrypt_init(EVP_PKEY_CTX *ctx);
  int EVP_PKEY_decrypt(EVP_PKEY_CTX *ctx, unsigned char *out, size_t *outlen, const unsigned char *in, size_t inlen);
]]

function encrypt(publicPEM, body)
  local bioIn = ffi.new("unsigned char[?]", #publicPEM)
  ffi.copy(bioIn, publicPEM, #publicPEM)
  local bio = ffi.C.BIO_new_mem_buf(bioIn, -1)
  local x509 = ffi.C.PEM_read_bio_X509(bio, nil, nil, nil)
  ffi.gc(x509, ffi.C.X509_free)
  local pKey = ffi.C.X509_get_pubkey(x509)
  local ctx = ffi.C.EVP_PKEY_CTX_new(pKey, nil)
  ffi.C.EVP_PKEY_encrypt_init(ctx)

  -- Adds OEAP padding
  ffi.C.EVP_PKEY_CTX_ctrl(ctx, 6, -1, 4097, 4, null)

  -- Get the length
  local outputLength = ffi.new("size_t[1]")
  ffi.C.EVP_PKEY_encrypt(ctx, nil, outputLength, body, #body)

  -- Encrypt into outputBuffer
  local outputBuffer = ffi.new("unsigned char[?]", outputLength[0])
  ffi.C.EVP_PKEY_encrypt(ctx, outputBuffer, outputLength, body, #body)

  -- Turn it into a string
  return ffi.string(outputBuffer, outputLength[0])
end

function decrypt(privatePEM, body)
  local bioIn = ffi.new("unsigned char[?]", #privatePEM)
  ffi.copy(bioIn, privatePEM, #privatePEM)
  local bio = ffi.C.BIO_new_mem_buf(bioIn, -1)
  if not bio then
    return nil
  end
  local rsa = ffi.C.PEM_read_bio_RSAPrivateKey(bio, nil, nil, nil)
  local pKey = ffi.C.EVP_PKEY_new()

  ffi.C.EVP_PKEY_set1_RSA(pKey, rsa)
  ctx = ffi.C.EVP_PKEY_CTX_new(pKey, nil)
  ffi.C.EVP_PKEY_decrypt_init(ctx)

  -- Adds OEAP padding
  ffi.C.EVP_PKEY_CTX_ctrl(ctx, 6, -1, 4097, 4, null)

  -- Get the length
  local outputLength = ffi.new("size_t[1]")
  ffi.C.EVP_PKEY_decrypt(ctx, nil, outputLength, body, #body)

  -- Decrypt into outputBuffer
  local outputBuffer = ffi.new("unsigned char[?]", outputLength[0])
  ffi.C.EVP_PKEY_decrypt(ctx, outputBuffer, outputLength, body, #body)

  -- Turn it into a string
  return ffi.string(outputBuffer, outputLength[0])
end

io.write("Result: "..tostring(decrypt([[-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
]], encrypt([[-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
]], "hello world"))).."\n")
Luajit succesfully loads, encrypts and decrypts the message but if I try to do the same thing with LÖVE, it fails with the following error:

Code: Select all

Error: main.lua:33: cannot resolve symbol 'BIO_new_mem_buf': The specified procedure could not be found.


stack traceback:
	[C]: in function '__index'
	main.lua:33: in function 'encrypt'
	main.lua:99: in function 'load'
	[string "boot.lua"]:439: in function <[string "boot.lua"]:435>
	[C]: in function 'xpcall'
This is my love:
RSA.love
(1.23 MiB) Downloaded 270 times
I belive it is windows only as it uses dlls.

Why can't LÖVE's jit load SSL's library and my locally installed jit can ?

Re: FFI can't resolve C symbols from SSL library.

Posted: Tue Jun 27, 2017 5:37 pm
by raidho36
I think you're supposed to call library functions via library handle, not ffi.C which is for standard library functions.

Re: FFI can't resolve C symbols from SSL library.

Posted: Tue Jun 27, 2017 5:45 pm
by Ranguna259
Changed ffi.C.BIO_new_mem_buf to ssl.BIO_new_mem_buf and I get the same error.
I belive ffi isn't even loading the library for some reason.

Re: FFI can't resolve C symbols from SSL library.

Posted: Tue Jun 27, 2017 5:49 pm
by zorg
Just to make sure, you are putting the dll in your löve executable's folder, and not your project's code/save folders, right?

Re: FFI can't resolve C symbols from SSL library.

Posted: Tue Jun 27, 2017 5:56 pm
by Ranguna259
I wasn't, tried copying the dlls to LÖVE's executable's folder and it gives me the same error.