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2018-07-16EC2M Lopez-Dahab ladder: use it also for ECDSA verifyNicola Tuveri
By default `ec_scalar_mul_ladder` (which uses the Lopez-Dahab ladder implementation) is used only for (k * Generator) or (k * VariablePoint). ECDSA verification uses (a * Generator + b * VariablePoint): this commit forces the use of `ec_scalar_mul_ladder` also for the ECDSA verification path, while using the default wNAF implementation for any other case. With this commit `ec_scalar_mul_ladder` loses the static attribute, and is added to ec_lcl.h so EC_METHODs can directly use it. While working on a new custom EC_POINTs_mul implementation, I realized that many checks (e.g. all the points being compatible with the given EC_GROUP, creating a temporary BN_CTX if `ctx == NULL`, check for the corner case `scalar == NULL && num == 0`) were duplicated again and again in every single implementation (and actually some implementations lacked some of the tests). I thought that it makes way more sense for those checks that are independent from the actual implementation and should always be done, to be moved in the EC_POINTs_mul wrapper: so this commit also includes these changes. Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6690)
2018-07-16EC point multiplication: add `ladder` scaffoldNicola Tuveri
for specialized Montgomery ladder implementations PR #6009 and #6070 replaced the default EC point multiplication path for prime and binary curves with a unified Montgomery ladder implementation with various timing attack defenses (for the common paths when a secret scalar is feed to the point multiplication). The newly introduced default implementation directly used EC_POINT_add/dbl in the main loop. The scaffolding introduced by this commit allows EC_METHODs to define a specialized `ladder_step` function to improve performances by taking advantage of efficient formulas for differential addition-and-doubling and different coordinate systems. - `ladder_pre` is executed before the main loop of the ladder: by default it copies the input point P into S, and doubles it into R. Specialized implementations could, e.g., use this hook to transition to different coordinate systems before copying and doubling; - `ladder_step` is the core of the Montgomery ladder loop: by default it computes `S := R+S; R := 2R;`, but specific implementations could, e.g., implement a more efficient formula for differential addition-and-doubling; - `ladder_post` is executed after the Montgomery ladder loop: by default it's a noop, but specialized implementations could, e.g., use this hook to transition back from the coordinate system used for optimizing the differential addition-and-doubling or recover the y coordinate of the result point. This commit also renames `ec_mul_consttime` to `ec_scalar_mul_ladder`, as it better corresponds to what this function does: nothing can be truly said about the constant-timeness of the overall execution of this function, given that the underlying operations are not necessarily constant-time themselves. What this implementation ensures is that the same fixed sequence of operations is executed for each scalar multiplication (for a given EC_GROUP), with no dependency on the value of the input scalar. Co-authored-by: Sohaib ul Hassan <soh.19.hassan@gmail.com> Co-authored-by: Billy Brumley <bbrumley@gmail.com> Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6690)
2018-07-04[crypto/ec] disable SCA mitigations for curves with incomplete parametersBilly Brumley
Reviewed-by: Rich Salz <rsalz@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6648)
2018-06-21[crypto/ec] don't assume points are of order group->orderBilly Brumley
Reviewed-by: Paul Dale <paul.dale@oracle.com> Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6535)
2018-06-19Implement coordinate blinding for EC_POINTSohaib ul Hassan
This commit implements coordinate blinding, i.e., it randomizes the representative of an elliptic curve point in its equivalence class, for prime curves implemented through EC_GFp_simple_method, EC_GFp_mont_method, and EC_GFp_nist_method. This commit is derived from the patch https://marc.info/?l=openssl-dev&m=131194808413635 by Billy Brumley. Coordinate blinding is a generally useful side-channel countermeasure and is (mostly) free. The function itself takes a few field multiplicationss, but is usually only necessary at the beginning of a scalar multiplication (as implemented in the patch). When used this way, it makes the values that variables take (i.e., field elements in an algorithm state) unpredictable. For instance, this mitigates chosen EC point side-channel attacks for settings such as ECDH and EC private key decryption, for the aforementioned curves. For EC_METHODs using different coordinate representations this commit does nothing, but the corresponding coordinate blinding function can be easily added in the future to extend these changes to such curves. Co-authored-by: Nicola Tuveri <nic.tuv@gmail.com> Co-authored-by: Billy Brumley <bbrumley@gmail.com> Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6501)
2018-05-24Improve compatibility of point and curve checksMatt Caswell
We check that the curve name associated with the point is the same as that for the curve. Fixes #6302 Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6323)
2018-05-09ECDSA: remove nonce padding (delegated to EC_POINT_mul)Billy Brumley
* EC_POINT_mul is now responsible for constant time point multiplication (for single fixed or variable point multiplication, when the scalar is in the range [0,group_order), so we need to strip the nonce padding from ECDSA. * Entry added to CHANGES * Updated EC_POINT_mul documentation - Integrate existing EC_POINT_mul and EC_POINTs_mul entries in the manpage to reflect the shift in constant-time expectations when performing a single fixed or variable point multiplication; - Add documentation to ec_method_st to reflect the updated "contract" between callers and implementations of ec_method_st.mul. Reviewed-by: Richard Levitte <levitte@openssl.org> Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6070)
2018-05-08ec/ec_mult.c: get BN_CTX_start,end sequence right.Andy Polyakov
Triggered by Coverity analysis. Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6190)
2018-05-01Update copyright yearMatt Caswell
Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6145)
2018-04-23Remove superfluous NULL checks. Add Andy's BN_FLG comment.Billy Brumley
Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6009)
2018-04-23Move up check for EC_R_INCOMPATIBLE_OBJECTS and for the point at infinity caseNicola Tuveri
Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6009)
2018-04-23Pass throughNicola Tuveri
Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6009)
2018-04-23ladder description: why it worksBilly Brumley
Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6009)
2018-04-23Address code style commentsNicola Tuveri
Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6009)
2018-04-23Elliptic curve scalar multiplication with timing attack defensesBilly Brumley
Co-authored-by: Nicola Tuveri <nic.tuv@gmail.com> Co-authored-by: Cesar Pereida Garcia <cesar.pereidagarcia@tut.fi> Co-authored-by: Sohaib ul Hassan <soh.19.hassan@gmail.com> Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/6009)
2017-12-07Consistent formatting for sizeof(foo)Rich Salz
Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/4872)
2017-08-30Move the REF_PRINT support from e_os.h to internal/refcount.h.Pauli
Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/4188)
2017-08-30e_os.h removal from other headers and source files.Pauli
Removed e_os.h from all bar three headers (apps/apps.h crypto/bio/bio_lcl.h and ssl/ssl_locl.h). Added e_os.h into the files that need it now. Directly reference internal/nelem.h when required. Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/4188)
2017-06-20Modify Sun copyright to follow OpenSSL styleRich Salz
Approved by Oracle. Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de> (Merged from https://github.com/openssl/openssl/pull/3585)
2017-05-02Fix URL links in commentRich Salz
Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/3365)
2016-11-17Add support for reference counting using C11 atomicsKurt Roeckx
Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Rich Salz <rsalz@openssl.org> GH: #1500
2016-06-01Free tempory data on error in ec_wNAF_mul()Matt Caswell
The ec_wNAF_mul() function allocates some temporary storage that it doesn't always free on an error condition. Reviewed-by: Richard Levitte <levitte@openssl.org>
2016-05-17Copyright consolidation 06/10Rich Salz
Reviewed-by: Richard Levitte <levitte@openssl.org>
2016-03-08Convert CRYPTO_LOCK_EC_* to new multi-threading APIAlessandro Ghedini
Reviewed-by: Matt Caswell <matt@openssl.org> Reviewed-by: Rich Salz <rsalz@openssl.org>
2016-03-05GH616: Remove dead codeRich Salz
Signed-off-by: Rich Salz <rsalz@openssl.org> Reviewed-by: Emilia Käsper <emilia@openssl.org>
2016-02-05GH601: Various spelling fixes.FdaSilvaYY
Signed-off-by: Rich Salz <rsalz@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org>
2016-01-31Add EC_GROUP_order_bits, EC_GROUP_get0_order and EC_GROUP_get0_cofactorDr. Stephen Henson
New functions to return internal pointer for order and cofactor. This avoids the need to allocate a new BIGNUM which to copy the value to. Simplify code to use new functions. Reviewed-by: Rich Salz <rsalz@openssl.org>
2016-01-26Remove /* foo.c */ commentsRich Salz
This was done by the following find . -name '*.[ch]' | /tmp/pl where /tmp/pl is the following three-line script: print unless $. == 1 && m@/\* .*\.[ch] \*/@; close ARGV if eof; # Close file to reset $. And then some hand-editing of other files. Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
2016-01-13Call single parent free_comp routine.Rich Salz
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
2016-01-13Add CRYPTO_EX_DATA; remove EC_EXTRA_DATARich Salz
Add CRYPTO_EX_DATA add EndC_KEY_[gs]et_method, From Roumen Petrov. Had to add various exdata calls to init/copy/free the exdata. Had to remove const from some EC functions because exdata isn't const-correct. :( Also remove EC_EXTRA_DATA and use a union to hold the possible pre-computed values and an enum to tell which value is in the union. (Rich Salz) Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
2015-11-09Continue standardising malloc style for libcryptoMatt Caswell
Continuing from previous commit ensure our style is consistent for malloc return checks. Reviewed-by: Kurt Roeckx <kurt@openssl.org>
2015-09-03remove 0 assignments.Rich Salz
After openssl_zalloc, cleanup more "set to 0/NULL" assignments. Many are from github feedback. Reviewed-by: Tim Hudson <tjh@openssl.org>
2015-05-11Use p==NULL not !p (in if statements, mainly)Rich Salz
Reviewed-by: Tim Hudson <tjh@openssl.org>
2015-05-04Use safer sizeof variant in mallocRich Salz
For a local variable: TYPE *p; Allocations like this are "risky": p = OPENSSL_malloc(sizeof(TYPE)); if the type of p changes, and the malloc call isn't updated, you could get memory corruption. Instead do this: p = OPENSSL_malloc(sizeof(*p)); Also fixed a few memset() calls that I noticed while doing this. Reviewed-by: Richard Levitte <levitte@openssl.org>
2015-05-01free NULL cleanup -- codaRich Salz
After the finale, the "real" final part. :) Do a recursive grep with "-B1 -w [a-zA-Z0-9_]*_free" to see if any of the preceeding lines are an "if NULL" check that can be removed. Reviewed-by: Tim Hudson <tjh@openssl.org>
2015-05-01free null cleanup finaleRich Salz
Don't check for NULL before calling OPENSSL_free Reviewed-by: Richard Levitte <levitte@openssl.org>
2015-04-30free NULL cleanup 7Rich Salz
This gets BN_.*free: BN_BLINDING_free BN_CTX_free BN_FLG_FREE BN_GENCB_free BN_MONT_CTX_free BN_RECP_CTX_free BN_clear_free BN_free BUF_MEM_free Also fix a call to DSA_SIG_free to ccgost engine and remove some #ifdef'd dead code in engines/e_ubsec. Reviewed-by: Richard Levitte <levitte@openssl.org>
2015-04-30free cleanup almost the finaleRich Salz
Add OPENSSL_clear_free which merges cleanse and free. (Names was picked to be similar to BN_clear_free, etc.) Removed OPENSSL_freeFunc macro. Fixed the small simple ones that are left: CRYPTO_free CRYPTO_free_locked OPENSSL_free_locked Reviewed-by: Richard Levitte <levitte@openssl.org>
2015-04-28remove malloc castsRich Salz
Following ANSI C rules, remove the casts from calls to OPENSSL_malloc and OPENSSL_realloc. Reviewed-by: Richard Levitte <levitte@openssl.org>
2015-03-25free NULL cleanup.Rich Salz
This gets EC_GROUP_clear_free EC_GROUP_free, EC_KEY_free, EC_POINT_clear_free, EC_POINT_free Reviewed-by: Kurt Roeckx <kurt@openssl.org>
2015-02-06Live code cleanup: remove #if 1 stuffRich Salz
For code bracketed by "#if 1" then remove the alternate "#else .. #endif" lines. Reviewed-by: Andy Polyakov <appro@openssl.org>
2015-01-22Re-align some comments after running the reformat script.Matt Caswell
This should be a one off operation (subsequent invokation of the script should not move them) Reviewed-by: Tim Hudson <tjh@openssl.org>
2015-01-22Run util/openssl-format-source -v -c .Matt Caswell
Reviewed-by: Tim Hudson <tjh@openssl.org>
2015-01-22Further comment changes for reformat (master)Matt Caswell
Reviewed-by: Tim Hudson <tjh@openssl.org>
2014-12-30mark all block comments that need format preserving so thatTim Hudson
indent will not alter them when reformatting comments Reviewed-by: Rich Salz <rsalz@openssl.org> Reviewed-by: Matt Caswell <matt@openssl.org>
2014-12-08Implement internally opaque bn access from ecMatt Caswell
Reviewed-by: Tim Hudson <tjh@openssl.org>
2014-12-08remove OPENSSL_FIPSAPIDr. Stephen Henson
Reviewed-by: Tim Hudson <tjh@openssl.org>
2014-11-12Fix free of garbage pointer. PR#3595Matt Caswell
Reviewed-by: Emilia Käsper <emilia@openssl.org>
2011-02-14Reorganise ECC code for inclusion in FIPS module.Dr. Stephen Henson
Move compression, point2oct and oct2point functions into separate files. Add a flags field to EC_METHOD. Add a flag EC_FLAGS_DEFAULT_OCT to use the default compession and oct functions (all existing methods do this). This removes dependencies from EC_METHOD while keeping original functionality.
2010-08-26ECC library bugfixes.Bodo Möller
Submitted by: Emilia Kasper (Google)