diff options
| author | Richard Levitte <levitte@openssl.org> | 2020-07-27 22:02:07 +0200 |
|---|---|---|
| committer | Pauli <paul.dale@oracle.com> | 2020-08-01 11:51:20 +1000 |
| commit | 1dbf4537738d86d8078b74c89e38b6ed0b2b1196 (patch) | |
| tree | 43e414c0958f6dbd04050b1cc8deb34e39f3a74a /crypto/bio | |
| parent | 3c033c5bfed214b02c0f041239d1cb8a4e27fd82 (diff) | |
DESERIALIZER: Make OSSL_DESERIALIZER_from_{bio,fp} use BIO_tell() / BIO_seek()
Depending on the BIO used, using BIO_reset() may lead to "interesting"
results. For example, a BIO_f_buffer() on top of another BIO that
handles BIO_reset() as a BIO_seek(bio, 0), the deserialization process
may find itself with a file that's rewound more than expected.
Therefore, OSSL_DESERIALIZER_from_{bio,fp}'s behaviour is changed to
rely purely on BIO_tell() / BIO_seek(), and since BIO_s_mem() is used
internally, it's changed to handle BIO_tell() and BIO_seek() better.
This does currently mean that OSSL_DESERIALIZER can't be easily used
with streams that don't support BIO_tell() / BIO_seek().
Fixes #12541
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/12544)
Diffstat (limited to 'crypto/bio')
| -rw-r--r-- | crypto/bio/bss_mem.c | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/crypto/bio/bss_mem.c b/crypto/bio/bss_mem.c index 4043043626..d9580e6d37 100644 --- a/crypto/bio/bss_mem.c +++ b/crypto/bio/bss_mem.c @@ -176,6 +176,7 @@ static int mem_buf_free(BIO *a) /* * Reallocate memory buffer if read pointer differs + * NOT FOR RDONLY */ static int mem_buf_sync(BIO *b) { @@ -247,12 +248,18 @@ static long mem_ctrl(BIO *b, int cmd, long num, void *ptr) long ret = 1; char **pptr; BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr; - BUF_MEM *bm; + BUF_MEM *bm, *bo; /* bio_mem, bio_other */ + long off, remain; - if (b->flags & BIO_FLAGS_MEM_RDONLY) + if (b->flags & BIO_FLAGS_MEM_RDONLY) { bm = bbm->buf; - else + bo = bbm->readp; + } else { bm = bbm->readp; + bo = bbm->buf; + } + off = bm->data - bo->data; + remain = bm->length; switch (cmd) { case BIO_CTRL_RESET: @@ -270,6 +277,18 @@ static long mem_ctrl(BIO *b, int cmd, long num, void *ptr) } } break; + case BIO_C_FILE_SEEK: + if (num < 0 || num > off + remain) + return -1; /* Can't see outside of the current buffer */ + + bm->data = bo->data + num; + bm->length = bo->length - num; + bm->max = bo->max - num; + off = num; + /* FALLTHRU */ + case BIO_C_FILE_TELL: + ret = off; + break; case BIO_CTRL_EOF: ret = (long)(bm->length == 0); break; |