CBS_asn1_ber_to_der currently uses heuristics because implicitly-tagged
constructed strings in BER are ambiguous with implicitly-tagged sequences. It's
not possible to convert BER to DER without knowing the schema.
Fortunately, implicitly tagged strings don't appear often so instead split the
job up: CBS_asn1_ber_to_der fixes indefinite-length elements and constructed
strings it can see. Implicitly-tagged strings it leaves uncoverted, but they
will only nest one level down (because BER kindly allows one to nest
constructed strings arbitrarily!).
CBS_get_asn1_implicit_string then performs the final concatenation at parse
time. This isn't much more complex and lets us parse BER more accurately and
also reject a number of mis-encoded values (e.g. constructed INTEGERs are not a
thing) we'd previously let through. The downside is the post-conversion parsing
code must be aware of this limitation of CBS_asn1_ber_to_der. Fortunately,
there's only one implicitly-tagged string in our PKCS#12 code.
(In the category of things that really really don't matter, but I had spare
cycles and the old BER converter is weird.)
Change-Id: Iebdd13b08559fa158b308ef83a5bb07bfdf80ae8
Reviewed-on: https://boringssl-review.googlesource.com/7052
Reviewed-by: Adam Langley <agl@google.com>
There is some messiness around saving and restoring the CBB, but this is
still significantly clearer.
Note that the BUF_MEM_grow line is gone in favor of a fixed CBB like the
other functions ported thus far. This line was never necessary as
init_buf is initialized to 16k and none of our key exchanges get that
large. (The largest one can get is DHE_RSA. Even so, it'd take a roughly
30k-bit DH group with a 30k-bit RSA key.)
Having such limits and tight assumptions on init_buf's initial size is
poor (but on par for the old code which usually just blindly assumed the
message would not get too large) and the size of the certificate chain
is much less obviously bounded, so those BUF_MEM_grows can't easily go.
My current plan is convert everything but those which legitimately need
BUF_MEM_grow to CBB, then atomically convert the rest, remove init_buf,
and switch everything to non-fixed CBBs. This will hopefully also
simplify async resumption. In the meantime, having a story for
resumption means the future atomic change is smaller and, more
importantly, relieves some complexity budget in the ServerKeyExchange
code for adding Curve25519.
Change-Id: I1de6af9856caaed353453d92a502ba461a938fbd
Reviewed-on: https://boringssl-review.googlesource.com/6770
Reviewed-by: Adam Langley <agl@google.com>
These will be needed when we start writing variable-length things to a
CBB.
Change-Id: Ie7b9b140f5f875b43adedc8203ce9d3f4068dfea
Reviewed-on: https://boringssl-review.googlesource.com/6764
Reviewed-by: Adam Langley <agl@google.com>
Rather than the length of the top-level CBB, which is kind of odd when ASN.1
length prefixes are not yet determined, return the number of bytes written to
the CBB so far. This can be computed without increasing the size of CBB at all.
Have offset and pending_*.
This means functions which take in a CBB as argument will not be sensitive to
whether the CBB is a top-level or child CBB. The extensions logic had to be
careful to only ever compare differences of lengths, which was awkward.
The reversal will also allow for the following pattern in the future, once
CBB_add_space is split into, say, CBB_reserve and CBB_did_write and we add a
CBB_data:
uint8_t *signature;
size_t signature_len = 0;
if (!CBB_add_asn1(out, &cert, CBB_ASN1_SEQUENCE) ||
/* Emit the TBSCertificate. */
!CBB_add_asn1(&cert, &tbs_cert, CBS_ASN1_SEQUENCE) ||
!CBB_add_tbs_cert_stuff(&tbs_cert, stuff) ||
!CBB_flush(&cert) ||
/* Feed it into md_ctx. */
!EVP_DigestSignInit(&md_ctx, NULL, EVP_sha256(), NULL, pkey) ||
!EVP_DigestSignUpdate(&md_ctx, CBB_data(&cert), CBB_len(&cert)) ||
/* Emit the signature algorithm. */
!CBB_add_asn1(&cert, &sig_alg, CBS_ASN1_SEQUENCE) ||
!CBB_add_sigalg_stuff(&sig_alg, other_stuff) ||
/* Emit the signature. */
!EVP_DigestSignFinal(&md_ctx, NULL, &signature_len) ||
!CBB_reserve(&cert, &signature, signature_len) ||
!EVP_DigestSignFinal(&md_ctx, signature, &signature_len) ||
!CBB_did_write(&cert, signature_len)) {
goto err;
}
(Were TBSCertificate not the first field, we'd still have to sample
CBB_len(&cert), but at least that's reasonable straight-forward. The
alternative would be if CBB_data and CBB_len somehow worked on
recently-invalidated CBBs, but that would go wrong once the invalidated CBB's
parent flushed and possibly shifts everything.)
And similar for signing ServerKeyExchange.
Change-Id: I7761e492ae472d7632875b5666b6088970261b14
Reviewed-on: https://boringssl-review.googlesource.com/6681
Reviewed-by: Adam Langley <agl@google.com>
Not sure if we want to leave bio.h and bytestring.h's instance as-is, but the
evp.h ones are just baffling.
Change-Id: I485c2e355ba93764da0c4c72c48af48b055a8500
Reviewed-on: https://boringssl-review.googlesource.com/6454
Reviewed-by: Adam Langley <agl@google.com>
Start converting the ones we can right now. Some of the messier ones
resize init_buf rather than assume the initial size is sufficient, so
those will probably wait until init_buf is gone and the handshake's
undergone some more invasive surgery. The async ones will also require
some thought. But some can be incrementally converted now.
BUG=468889
Change-Id: I0bc22e4dca37d9d671a488c42eba864c51933638
Reviewed-on: https://boringssl-review.googlesource.com/6190
Reviewed-by: Adam Langley <alangley@gmail.com>
Also add an assert to that effect.
Change-Id: I1bd0571e3889f1cba968fd99041121ac42ee9e89
Reviewed-on: https://boringssl-review.googlesource.com/5990
Reviewed-by: Adam Langley <agl@google.com>
This is useful to skip an optional element, and mirrors the behaviour of
CBS_get_optional_asn1_octet_string.
Change-Id: Icb538c5e99a1d4e46412cae3c438184a94fab339
Reviewed-on: https://boringssl-review.googlesource.com/5800
Reviewed-by: Adam Langley <agl@google.com>
This begins decoupling the transport from the SSL state machine. The buffering
logic is hidden behind an opaque API. Fields like ssl->packet and
ssl->packet_length are gone.
ssl3_get_record and dtls1_get_record now call low-level tls_open_record and
dtls_open_record functions that unpack a single record independent of who owns
the buffer. Both may be called in-place. This removes ssl->rstate which was
redundant with the buffer length.
Future work will push the buffer up the stack until it is above the handshake.
Then we can expose SSL_open and SSL_seal APIs which act like *_open_record but
return a slightly larger enum due to other events being possible. Likewise the
handshake state machine will be detached from its buffer. The existing
SSL_read, SSL_write, etc., APIs will be implemented on top of SSL_open, etc.,
combined with ssl_read_buffer_* and ssl_write_buffer_*. (Which is why
ssl_read_buffer_extend still tries to abstract between TLS's and DTLS's fairly
different needs.)
The new buffering logic does not support read-ahead (removed previously) since
it lacks a memmove on ssl_read_buffer_discard for TLS, but this could be added
if desired. The old buffering logic wasn't quite right anyway; it tried to
avoid the memmove in some cases and could get stuck too far into the buffer and
not accept records. (The only time the memmove is optional is in DTLS or if
enough of the record header is available to know that the entire next record
would fit in the buffer.)
The new logic also now actually decrypts the ciphertext in-place again, rather
than almost in-place when there's an explicit nonce/IV. (That accidentally
switched in https://boringssl-review.googlesource.com/#/c/4792/; see
3d59e04bce96474099ba76786a2337e99ae14505.)
BUG=468889
Change-Id: I403c1626253c46897f47c7ae93aeab1064b767b2
Reviewed-on: https://boringssl-review.googlesource.com/5715
Reviewed-by: Adam Langley <agl@google.com>
It switched from CBB_remaining to CBB_len partway through review, but
the semantics are still CBB_remaining. Using CBB_len allows the
len_before/len_after logic to continue working even if, in the future,
handshake messages are built on a non-fixed CBB.
Change-Id: Id466bb341a14dbbafcdb26e4c940a04181f2787d
Reviewed-on: https://boringssl-review.googlesource.com/5371
Reviewed-by: Adam Langley <agl@google.com>
One tedious thing about using CBB is that you can't safely CBB_cleanup
until CBB_init is successful, which breaks the general 'goto err' style
of cleanup. This makes it possible:
CBB_zero ~ EVP_MD_CTX_init
CBB_init ~ EVP_DigestInit
CBB_cleanup ~ EVP_MD_CTX_cleanup
Change-Id: I085ecc4405715368886dc4de02285a47e7fc4c52
Reviewed-on: https://boringssl-review.googlesource.com/5267
Reviewed-by: Adam Langley <agl@google.com>
Rather than four massive functions that handle every extension,
organise the code by extension with four smaller functions for each.
Change-Id: I876b31dacb05aca9884ed3ae7c48462e6ffe3b49
Reviewed-on: https://boringssl-review.googlesource.com/5142
Reviewed-by: Adam Langley <agl@google.com>
Some of the documentation had the right explanation but the incorrect
function names attached.
Change-Id: I7b479dae6d71a5ac7bc86df5a3890508c3b3d09f
Reviewed-on: https://boringssl-review.googlesource.com/5090
Reviewed-by: Adam Langley <agl@google.com>
We have need of it internally.
Change-Id: I564af468728b22245e8eab384ea7018b7e88cc86
Reviewed-on: https://boringssl-review.googlesource.com/5022
Reviewed-by: Matt Braithwaite <mab@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Change-Id: Ic82ab5de4e231cdf6230ee7262c3c7539404d4a6
Reviewed-on: https://boringssl-review.googlesource.com/5020
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
This change makes |CBS_get_any_asn1_element| only handle DER elements.
Another function, |CBS_get_any_ber_asn1_element| is exposed internally
for the cases where we need to process BER data.
Change-Id: I544141a1a3d7913986352a8fd9a6d00b9f282652
Reviewed-on: https://boringssl-review.googlesource.com/4994
Reviewed-by: Adam Langley <agl@google.com>
Tag number 31 is a long form tag that requires multiple octets. It
cannot be handled by adding a single uint8. Changed CBB_add_asn1()
to return 0 when it is passed in the extension for tag 31.
Change-Id: Ia33936d4f174d1a7176eb11da0b5c7370efb9416
CBS_get_asn1() and CBS_get_any_asn1_element() only support the single
byte ASN.1 identifier octets (aka short form tags). Tag number 31 is
the start of the multi-byte long form per X.690 section 8.1.2.4.
Change-Id: I892600f4946e880a4ff03d219181116ef04f5372
Reviewed-on: https://boringssl-review.googlesource.com/3241
Reviewed-by: Adam Langley <agl@google.com>
Add some missing headers and ensure each header has a short description. doc.go
gets confused at declarations that break before the first (, so avoid doing
that. Also skip a/an/deprecated: in markupFirstWord and process pipe words in
the table of contents.
Change-Id: Ia08ec5ae8e496dd617e377e154eeea74f4abf435
Reviewed-on: https://boringssl-review.googlesource.com/2839
Reviewed-by: Adam Langley <agl@google.com>
Do away with all those unreadable macros. Also fix many many memory leaks in
the SSL_SESSION reuse case. Add a number of helper functions in CBS to help
with parsing optional fields.
Change-Id: I2ce8fd0d5b060a1b56e7f99f7780997fabc5ce41
Reviewed-on: https://boringssl-review.googlesource.com/1998
Reviewed-by: Adam Langley <agl@google.com>
Companion to CBS_get_asn1_uint64. Also add tests for both the parsing and the
serializing.
Change-Id: Ic5e9a0089c88b300f874712d0e9964cb35a8c40b
Reviewed-on: https://boringssl-review.googlesource.com/1999
Reviewed-by: Adam Langley <agl@google.com>
Intended to make parsing ASN.1 structures with OPTIONAL elements easier. (Just
attempting to parse the next tag doesn't distinguish between a malformed CBS
which has now been partially advanced and an optional tag mismatch.)
Change-Id: Idceb3dfd6ec028e87e1bc5aaddcec177b0c32150
Reviewed-on: https://boringssl-review.googlesource.com/1995
Reviewed-by: Adam Langley <agl@google.com>
Useful for parsing things when you don't know what tag to expect (e.g. a
CHOICE). Also allow its operands to be NULL, so that it can be used to skip
arbitrary elements.
Delete CBS_ASN1_ANY which wasn't doing anything.
Change-Id: I56413e68b4f2e13860ea3e55373d5830713d7e5c
Reviewed-on: https://boringssl-review.googlesource.com/1661
Reviewed-by: Adam Langley <agl@google.com>
Previously, the ASN.1 functions in bytestring were capable of processing
indefinite length elements when the _ber functions were used. That works
well enough for PKCS#3, but NSS goes a bit crazy with BER encoding and
PKCS#12. Rather than complicate the core bytestring functions further,
the BER support is removed from them and moved to a separate function
that converts from BER to DER (if needed).
Change-Id: I2212b28e99bab9fab8c61f80d2012d3e5a3cc2f0
Reviewed-on: https://boringssl-review.googlesource.com/1591
Reviewed-by: Adam Langley <agl@google.com>
This function serialises a PKCS#7 structure containing a number of
certificates.
Change-Id: Iaf15887e1060d5d201d5a3dd3dca8d51105ee6d6
Reviewed-on: https://boringssl-review.googlesource.com/1431
Reviewed-by: Adam Langley <agl@google.com>
This change marks public symbols as dynamically exported. This means
that it becomes viable to build a shared library of libcrypto and libssl
with -fvisibility=hidden.
On Windows, one not only needs to mark functions for export in a
component, but also for import when using them from a different
component. Because of this we have to build with
|BORINGSSL_IMPLEMENTATION| defined when building the code. Other
components, when including our headers, won't have that defined and then
the |OPENSSL_EXPORT| tag becomes an import tag instead. See the #defines
in base.h
In the asm code, symbols are now hidden by default and those that need
to be exported are wrapped by a C function.
In order to support Chromium, a couple of libssl functions were moved to
ssl.h from ssl_locl.h: ssl_get_new_session and ssl_update_cache.
Change-Id: Ib4b76e2f1983ee066e7806c24721e8626d08a261
Reviewed-on: https://boringssl-review.googlesource.com/1350
Reviewed-by: Adam Langley <agl@google.com>
Also fix some DTLS cookie bugs. rcvd_cookie is never referenced after being
saved (and the length isn't saved, so it couldn't be used anyway), and the
cookie verification failed to check the length.
For convenience, add a CBS_mem_equal helper function. Saves a bit of
repetition.
Change-Id: I187137733b069f0ac8d8b1bf151eeb80d388b971
Reviewed-on: https://boringssl-review.googlesource.com/1174
Reviewed-by: Adam Langley <agl@google.com>
Also tidy up some variable names and update RSA_verify call for it no longer
returning -1. Add CBS helper functions for dealing with C strings.
Change-Id: Ibc398d27714744f5d99d4f94ae38210cbc89471a
Reviewed-on: https://boringssl-review.googlesource.com/1164
Reviewed-by: Adam Langley <agl@google.com>
Previously, public headers lived next to the respective code and there
were symlinks from include/openssl to them.
This doesn't work on Windows.
This change moves the headers to live in include/openssl. In cases where
some symlinks pointed to the same header, I've added a file that just
includes the intended target. These cases are all for backwards-compat.
Change-Id: I6e285b74caf621c644b5168a4877db226b07fd92
Reviewed-on: https://boringssl-review.googlesource.com/1180
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
Initial fork from f2d678e6e89b6508147086610e985d4e8416e867 (1.0.2 beta).
(This change contains substantial changes from the original and
effectively starts a new history.)
