Commit 5721ec22 authored by Nick Mathewson's avatar Nick Mathewson 🦀
Browse files

pem_decode(): Tolerate CRLF line endings 

Fixes bug 33032; bugfix on 0.3.5.1-alpha when we introduced our own
PEM decoder.
parent b9c7c61e

changes/bug33032

0 → 100644
+6 −0
Original line number Diff line number Diff line 
  o Minor bugfixes (key portability):

    - When reading PEM-encoded key data, tolerate CRLF line-endings even if

      we are not running on Windows. Previously, non-Windows hosts

      would reject these line-endings in certain positions, making

      certain key files hard to move from one host to another.

      Fixes bug 33032; bugfix on 0.3.5.1-alpha.

src/lib/encoding/pem.c

+7 −1
Original line number Diff line number Diff line
@@ -85,13 +85,19 @@ pem_decode(uint8_t *dest, size_t destlen, const char *src, size_t srclen, 
  src = eat_whitespace_eos(src, eos);



  char *tag = NULL;

  tor_asprintf(&tag, "-----BEGIN %s-----\n", objtype);

  tor_asprintf(&tag, "-----BEGIN %s-----", objtype);

  if ((size_t)(eos-src) < strlen(tag) || fast_memneq(src, tag, strlen(tag))) {

    tor_free(tag);

    return -1;

  }

  src += strlen(tag);

  tor_free(tag);

  /* At this point we insist on spaces (including CR), then an LF. */

  src = eat_whitespace_eos_no_nl(src, eos);

  if (src == eos || *src != '\n') {

    /* Extra junk at end of line: this isn't valid. */

    return -1;

  }



  // NOTE lack of trailing \n.  We do not enforce its presence.

  tor_asprintf(&tag, "\n-----END %s-----", objtype);

src/test/test_pem.c

+30 −0
Original line number Diff line number Diff line
@@ -115,8 +115,38 @@ test_crypto_pem_decode(void *arg) 
  ;

}



static void

test_crypto_pem_decode_crlf(void *arg)

{

  (void)arg;

  char crlf_version[4096];

  uint8_t buf[4096];



  /* Convert 'expected' to a version with CRLF instead of LF. */

  const char *inp = expected;

  char *outp = crlf_version;

  while (*inp) {

    if (*inp == '\n') {

      *outp++ = '\r';

    }

    *outp++ = *inp++;

  }

  *outp = 0;



  /* Decoding should succeed (or else we have bug 33032 again) */

  int n = pem_decode(buf, sizeof(buf),

                     crlf_version, strlen(crlf_version),

                     "WOMBAT QUOTE");

  tt_int_op(n, OP_EQ, strlen(example_pre));

  tt_mem_op(buf, OP_EQ, example_pre, n);



 done:

  ;

}



struct testcase_t pem_tests[] = {

  { "encode", test_crypto_pem_encode, 0, NULL, NULL },

  { "decode", test_crypto_pem_decode, 0, NULL, NULL },

  { "decode_crlf", test_crypto_pem_decode_crlf, 0, NULL, NULL },

  END_OF_TESTCASES

};