summaryrefslogtreecommitdiffstats
path: root/debian/vendor-h2o/deps/picotls/deps/cifra/src/drbg.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--debian/vendor-h2o/deps/picotls/deps/cifra/src/drbg.c434
1 files changed, 0 insertions, 434 deletions
diff --git a/debian/vendor-h2o/deps/picotls/deps/cifra/src/drbg.c b/debian/vendor-h2o/deps/picotls/deps/cifra/src/drbg.c
deleted file mode 100644
index ae79067..0000000
--- a/debian/vendor-h2o/deps/picotls/deps/cifra/src/drbg.c
+++ /dev/null
@@ -1,434 +0,0 @@
-/*
- * cifra - embedded cryptography library
- * Written in 2016 by Joseph Birr-Pixton <jpixton@gmail.com>
- *
- * To the extent possible under law, the author(s) have dedicated all
- * copyright and related and neighboring rights to this software to the
- * public domain worldwide. This software is distributed without any
- * warranty.
- *
- * You should have received a copy of the CC0 Public Domain Dedication
- * along with this software. If not, see
- * <http://creativecommons.org/publicdomain/zero/1.0/>.
- */
-
-#include "drbg.h"
-#include "handy.h"
-#include "bitops.h"
-#include "sha2.h"
-#include "tassert.h"
-
-#include <string.h>
-
-#define MAX_DRBG_GENERATE 0x10000ul
-
-static void hash_df(const cf_chash *H,
- const void *in1, size_t nin1,
- const void *in2, size_t nin2,
- const void *in3, size_t nin3,
- const void *in4, size_t nin4,
- uint8_t *out, size_t nout)
-{
- uint8_t counter = 1;
- uint32_t bits_to_return = nout * 8;
- uint8_t cbuf[4];
- uint8_t block[CF_MAXHASH];
-
- write32_be(bits_to_return, cbuf);
-
- while (nout)
- {
- /* Make a block. This is the hash of:
- * counter || bits_to_return || in1 || in2 || in3 | in4
- */
- cf_chash_ctx ctx;
- H->init(&ctx);
- H->update(&ctx, &counter, sizeof counter);
- H->update(&ctx, cbuf, sizeof cbuf);
- H->update(&ctx, in1, nin1);
- H->update(&ctx, in2, nin2);
- H->update(&ctx, in3, nin3);
- H->update(&ctx, in4, nin4);
- H->digest(&ctx, block);
-
- size_t take = MIN(H->hashsz, nout);
- memcpy(out, block, take);
- out += take;
- nout -= take;
-
- counter += 1;
- }
-}
-
-void cf_hash_drbg_sha256_init(cf_hash_drbg_sha256 *ctx,
- const void *entropy, size_t nentropy,
- const void *nonce, size_t nnonce,
- const void *persn, size_t npersn)
-{
- mem_clean(ctx, sizeof *ctx);
-
- /* 1. seed_material = entropy_input || nonce || personalization_string
- * 2. seed = Hash_df(seed_material, seedlen)
- * 3. V = seed */
- hash_df(&cf_sha256,
- entropy, nentropy,
- nonce, nnonce,
- persn, npersn,
- NULL, 0,
- ctx->V, sizeof ctx->V);
-
- /* 4. C = Hash_df(0x00 || V, seedlen) */
- uint8_t zero = 0;
- hash_df(&cf_sha256,
- &zero, sizeof zero,
- ctx->V, sizeof ctx->V,
- NULL, 0,
- NULL, 0,
- ctx->C, sizeof ctx->C);
-
- /* 5. reseed_counter = 1 */
- ctx->reseed_counter = 1;
-}
-
-/* Add out += in, mod 2^nout.
- * Runs in time dependent on nout and nin, but not the contents of out or in.
- */
-static void add(uint8_t *out, size_t nout, const uint8_t *in, size_t nin)
-{
- assert(nout >= nin);
-
- uint16_t carry = 0;
- int oi, ii;
-
- for (oi = nout - 1, ii = nin - 1;
- oi >= 0;
- ii--, oi--)
- {
- carry += out[oi];
- if (ii >= 0)
- carry += in[ii];
- out[oi] = carry & 0xff;
- carry >>= 8;
- }
-}
-
-static void hash_process_addnl(const cf_chash *H,
- const void *input, size_t ninput,
- uint8_t *V, size_t nV)
-{
- if (!ninput)
- return;
-
- /* 2.1. w = Hash(0x02 || V || additional_input) */
- uint8_t two = 2;
- uint8_t w[CF_MAXHASH];
- cf_chash_ctx ctx;
- H->init(&ctx);
- H->update(&ctx, &two, sizeof two);
- H->update(&ctx, V, nV);
- H->update(&ctx, input, ninput);
- H->digest(&ctx, w);
-
- /* 2.2. V = (V + w) mod 2 ^ seedlen */
- add(V, nV, w, H->hashsz);
-}
-
-static void hash_generate(const cf_chash *H,
- uint8_t *data, size_t ndata, /* initialised with V */
- void *out, size_t nout)
-{
- cf_chash_ctx ctx;
- uint8_t w[CF_MAXHASH];
- uint8_t *bout = out;
- uint8_t one = 1;
-
- while (nout)
- {
- /* 4.1. w = Hash(data) */
- H->init(&ctx);
- H->update(&ctx, data, ndata);
- H->digest(&ctx, w);
-
- /* 4.2. W = W || w */
- size_t take = MIN(H->hashsz, nout);
- memcpy(bout, w, take);
- bout += take;
- nout -= take;
-
- /* 4.3. data = (data + 1) mod 2 ^ seedlen */
- add(data, ndata, &one, sizeof one);
- }
-}
-
-static void hash_step(const cf_chash *H,
- uint8_t *V, size_t nV,
- const uint8_t *C, size_t nC,
- uint32_t *reseed_counter)
-{
- /* 4. h = Hash(0x03 || V) */
- uint8_t h[CF_MAXHASH];
- uint8_t three = 3;
- cf_chash_ctx ctx;
-
- H->init(&ctx);
- H->update(&ctx, &three, sizeof three);
- H->update(&ctx, V, nV);
- H->digest(&ctx, h);
-
- /* 5. V = (V + h + C + reseed_counter) mod 2 ^ seedlen */
- uint8_t reseed_counter_buf[4];
- write32_be(*reseed_counter, reseed_counter_buf);
-
- add(V, nV, h, H->hashsz);
- add(V, nV, C, nC);
- add(V, nV, reseed_counter_buf, sizeof reseed_counter_buf);
-
- /* 6. reseed_counter = reseed_counter + 1 */
- *reseed_counter = *reseed_counter + 1;
-}
-
-/* This is Hash_DRBG_Generate_algorithm.
- * nout is a maximum of MAX_DRBG_GENERATE */
-static void hash_gen_request(cf_hash_drbg_sha256 *ctx,
- const void *addnl, size_t naddnl,
- void *out, size_t nout)
-{
- uint8_t data[440/8]; /* a temporary copy of V, which gets incremented by generate */
-
- assert(!cf_hash_drbg_sha256_needs_reseed(ctx));
-
- hash_process_addnl(&cf_sha256, addnl, naddnl, ctx->V, sizeof ctx->V);
- assert(sizeof data == sizeof ctx->V);
- memcpy(data, ctx->V, sizeof ctx->V);
- hash_generate(&cf_sha256, data, sizeof data, out, nout);
- hash_step(&cf_sha256, ctx->V, sizeof ctx->V, ctx->C, sizeof ctx->C, &ctx->reseed_counter);
-}
-
-void cf_hash_drbg_sha256_gen_additional(cf_hash_drbg_sha256 *ctx,
- const void *addnl, size_t naddnl,
- void *out, size_t nout)
-{
- uint8_t *bout = out;
-
- /* Generate output in requests of MAX_DRBG_GENERATE in size. */
- while (nout != 0)
- {
- size_t take = MIN(MAX_DRBG_GENERATE, nout);
- hash_gen_request(ctx, addnl, naddnl, bout, take);
- bout += take;
- nout -= take;
-
- /* Add additional data only once. */
- addnl = NULL;
- naddnl = 0;
- }
-}
-
-void cf_hash_drbg_sha256_gen(cf_hash_drbg_sha256 *ctx,
- void *out, size_t nout)
-{
- cf_hash_drbg_sha256_gen_additional(ctx,
- NULL, 0,
- out, nout);
-}
-
-void cf_hash_drbg_sha256_reseed(cf_hash_drbg_sha256 *ctx,
- const void *entropy, size_t nentropy,
- const void *addnl, size_t naddnl)
-{
- /* 1. seed_material = 0x01 || V || entropy_input || additional_input
- * 2. seed = Hash_df(seed_material, seedlen)
- * 3. V = seed */
- uint8_t one = 1;
- /* stash V in C, because it cannot alias output */
- memcpy(ctx->C, ctx->V, sizeof ctx->C);
- hash_df(&cf_sha256,
- &one, sizeof one,
- ctx->C, sizeof ctx->C,
- entropy, nentropy,
- addnl, naddnl,
- ctx->V, sizeof ctx->V);
-
- /* 4. C = Hash_df(0x00 || V, seedlen) */
- uint8_t zero = 0;
- hash_df(&cf_sha256,
- &zero, sizeof zero,
- ctx->V, sizeof ctx->V,
- NULL, 0,
- NULL, 0,
- ctx->C, sizeof ctx->C);
-
- /* 5. reseed_counter = 1 */
- ctx->reseed_counter = 1;
-}
-
-uint32_t cf_hash_drbg_sha256_needs_reseed(const cf_hash_drbg_sha256 *ctx)
-{
- /* we need reseeding after 2 ^ 32 - 1 requests. */
- return ctx->reseed_counter == 0;
-}
-
-/* --- HMAC_DRBG --- */
-
-/* provided_data is in1 || in2 || in3.
- * K is already scheduled in ctx->hmac. */
-static void hmac_drbg_update(cf_hmac_drbg *ctx,
- const void *in1, size_t nin1,
- const void *in2, size_t nin2,
- const void *in3, size_t nin3)
-{
- cf_hmac_ctx local;
- const cf_chash *H = ctx->hmac.hash;
- uint8_t new_key[CF_MAXHASH];
- uint8_t zero = 0;
-
- /* 1. K = HMAC(K, V || 0x00 || provided_data) */
- local = ctx->hmac;
- cf_hmac_update(&local, ctx->V, H->hashsz);
- cf_hmac_update(&local, &zero, sizeof zero);
- cf_hmac_update(&local, in1, nin1);
- cf_hmac_update(&local, in2, nin2);
- cf_hmac_update(&local, in3, nin3);
- cf_hmac_finish(&local, new_key);
- cf_hmac_init(&ctx->hmac, H, new_key, H->hashsz);
- mem_clean(new_key, sizeof new_key);
-
- /* 2. V = HMAC(K, V) */
- local = ctx->hmac;
- cf_hmac_update(&local, ctx->V, H->hashsz);
- cf_hmac_finish(&local, ctx->V);
-
- /* 3. if (provided_data = null) then return K and V */
- if (nin1 == 0 && nin2 == 0 && nin3 == 0)
- return;
-
- /* 4. K = HMAC(K, V || 0x01 || provided_data) */
- uint8_t one = 1;
- local = ctx->hmac;
- cf_hmac_update(&local, ctx->V, H->hashsz);
- cf_hmac_update(&local, &one, sizeof one);
- cf_hmac_update(&local, in1, nin1);
- cf_hmac_update(&local, in2, nin2);
- cf_hmac_update(&local, in3, nin3);
- cf_hmac_finish(&local, new_key);
- cf_hmac_init(&ctx->hmac, H, new_key, H->hashsz);
- mem_clean(new_key, sizeof new_key);
-
- /* 5. V = HMAC(K, V) */
- local = ctx->hmac;
- cf_hmac_update(&local, ctx->V, H->hashsz);
- cf_hmac_finish(&local, ctx->V);
-}
-
-void cf_hmac_drbg_init(cf_hmac_drbg *ctx,
- const cf_chash *hash,
- const void *entropy, size_t nentropy,
- const void *nonce, size_t nnonce,
- const void *persn, size_t npersn)
-{
- mem_clean(ctx, sizeof *ctx);
-
- assert(hash->hashsz <= CF_MAXHASH);
-
- /* 2. Key = 0x00 00 ... 00
- * 3. V = 0x01 01 ... 01 */
- uint8_t initial_key[CF_MAXHASH];
- memset(initial_key, 0x00, hash->hashsz);
- memset(ctx->V, 0x01, hash->hashsz);
- cf_hmac_init(&ctx->hmac, hash, initial_key, hash->hashsz);
-
- /* 1. seed_material = entropy_input || nonce || personalization_string
- * 4. (Key, V) = HMAC_DRBG_Update(seed_material, Key, V) */
- hmac_drbg_update(ctx, entropy, nentropy, nonce, nnonce, persn, npersn);
-
- /* 5. reseed_counter = 1 */
- ctx->reseed_counter = 1;
-}
-
-uint32_t cf_hmac_drbg_needs_reseed(const cf_hmac_drbg *ctx)
-{
- return ctx->reseed_counter == 0;
-}
-
-static void hmac_drbg_generate(cf_hmac_drbg *ctx,
- const void *addnl, size_t naddnl,
- void *out, size_t nout)
-{
- /* 1. If reseed_counter > reseed_interval, then return an indication
- * that a reseed is required */
- assert(!cf_hmac_drbg_needs_reseed(ctx));
-
- /* 2. If additional_input != null, then
- * (Key, V) = HMAC_DRBG_Update(additional_input, Key, V)
- */
- if (naddnl)
- hmac_drbg_update(ctx, addnl, naddnl, NULL, 0, NULL, 0);
-
- /* 3. temp = Null
- * 4. While (len(temp) < requested_number_of_bits) do:
- * 4.1. V = HMAC(Key, V)
- * 4.2. temp = temp || V
- * 5. returned_bits = leftmost(temp, requested_number_of_bits)
- *
- * We write the contents of temp directly into the caller's
- * out buffer.
- */
- uint8_t *bout = out;
- cf_hmac_ctx local;
-
- while (nout)
- {
- local = ctx->hmac;
- cf_hmac_update(&local, ctx->V, ctx->hmac.hash->hashsz);
- cf_hmac_finish(&local, ctx->V);
-
- size_t take = MIN(ctx->hmac.hash->hashsz, nout);
- memcpy(bout, ctx->V, take);
- bout += take;
- nout -= take;
- }
-
- /* 6. (Key, V) = HMAC_DRBG_Update(additional_input, Key, V) */
- hmac_drbg_update(ctx, addnl, naddnl, NULL, 0, NULL, 0);
-
- /* 7. reseed_counter = reseed_counter + 1 */
- ctx->reseed_counter++;
-}
-
-void cf_hmac_drbg_gen_additional(cf_hmac_drbg *ctx,
- const void *addnl, size_t naddnl,
- void *out, size_t nout)
-{
- uint8_t *bout = out;
-
- while (nout != 0)
- {
- size_t take = MIN(MAX_DRBG_GENERATE, nout);
- hmac_drbg_generate(ctx, addnl, naddnl, bout, take);
- bout += take;
- nout -= take;
-
- /* Add additional data only once. */
- addnl = NULL;
- naddnl = 0;
- }
-}
-
-void cf_hmac_drbg_gen(cf_hmac_drbg *ctx, void *out, size_t nout)
-{
- cf_hmac_drbg_gen_additional(ctx,
- NULL, 0,
- out, nout);
-}
-
-void cf_hmac_drbg_reseed(cf_hmac_drbg *ctx,
- const void *entropy, size_t nentropy,
- const void *addnl, size_t naddnl)
-{
- /* 1. seed_material = entropy_input || additional_input
- * 2. (Key, V) = HMAC_DRBG_Update(seed_material, Key, V) */
- hmac_drbg_update(ctx, entropy, nentropy, addnl, naddnl, NULL, 0);
-
- /* 3. reseed_counter = 1 */
- ctx->reseed_counter = 1;
-}