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libgcrypt/v9-0001-SP800-90A-Deterministic-Random-Bit-Generator.patch
Ismail Dönmez 1521b4e1a9 Accepting request 247239 from home:vitezslav_cizek:branches:devel:libraries:c_c++ 
- fix an issue in DRBG patchset
  * size_t type is 32-bit on 32-bit systems
- fix a potential NULL pointer deference in DRBG patchset
  * patches from https://bugs.g10code.com/gnupg/issue1701
- added v9-0001-SP800-90A-Deterministic-Random-Bit-Generator.patch
- added v9-0007-User-interface-to-DRBG.patch
- removed v7-0001-SP800-90A-Deterministic-Random-Bit-Generator.patch
- removed v7-0007-User-interface-to-DRBG.patch
- add a subpackage for CAVS testing
  * add cavs_driver.pl and cavs-test.sh from the kernel cavs package
  * added drbg_test.patch

OBS-URL: https://build.opensuse.org/request/show/247239
OBS-URL: https://build.opensuse.org/package/show/devel:libraries:c_c++/libgcrypt?expand=0&rev=61
2014-09-02 17:36:56 +00:00

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From 6e04a47db68a0ae3947dbd5bfdb8c228ddb83c0e Mon Sep 17 00:00:00 2001
From: Stephan Mueller <smueller@chronox.de>
Date: Mon, 1 Sep 2014 17:53:33 +0200
Subject: [PATCH v9 1/7] SP800-90A Deterministic Random Bit Generator
This is a clean-room implementation of the DRBG defined in SP800-90A.
All three viable DRBGs defined in the standard are implemented:
* HMAC: This is the leanest DRBG and compiled per default
* Hash: The more complex DRBG can be enabled at compile time
* CTR: The most complex DRBG can also be enabled at compile time
The DRBG implementation offers the following:
* All three DRBG types are implemented with a derivation function.
* All DRBG types are available with and without prediction resistance.
* All SHA types of SHA-1, SHA-256, SHA-384, SHA-512 are available for
* the HMAC and Hash DRBGs.
* All AES types of AES-128, AES-192 and AES-256 are available for the
* CTR DRBG.
* A self test is implemented with drbg_healthcheck().
* The FIPS 140-2 continuous self test is implemented.
* Additional cipher primitives, such as Serpent or Twofish, can be
* added to the DRBG without changing the implementation. The only
* change necessary is to the DRBG definition given in the cores[]
* array.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
random/drbg.c | 2364 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 2364 insertions(+)
create mode 100644 random/drbg.c
diff --git a/random/drbg.c b/random/drbg.c
new file mode 100644
index 0000000..8733f85
--- /dev/null
+++ b/random/drbg.c
@@ -0,0 +1,2364 @@
+/*
+ * DRBG: Deterministic Random Bits Generator
+ * Based on NIST Recommended DRBG from NIST SP800-90A with the following
+ * properties:
+ * * CTR DRBG with DF with AES-128, AES-192, AES-256 cores
+ * * Hash DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * HMAC DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores
+ * * with and without prediction resistance
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2014
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ *
+ * gcry_control GCRYCTL_DRBG_REINIT
+ * ================================
+ * This control request re-initializes the DRBG completely, i.e. the entire
+ * state of the DRBG is zeroized (with two exceptions listed in
+ * GCRYCTL_DRBG_SET_ENTROPY).
+ *
+ * The control request takes the following values which influences how the DRBG
+ * is re-initialized:
+ * * __u32 flags: This variable specifies the DRBG type to be used for the
+ * next initialization. If set to 0, the previous DRBG type is
+ * used for the initialization. The DRBG type is an OR of the
+ * mandatory flags of the requested DRBG strength and DRBG
+ * cipher type. Optionally, the prediction resistance flag
+ * can be ORed into the flags variable. For example:
+ * - CTR-DRBG with AES-128 without prediction resistance:
+ * DRBG_CTRAES128
+ * - HMAC-DRBG with SHA-512 with prediction resistance:
+ * DRBG_HMACSHA512 | DRBG_PREDICTION_RESIST
+ * * struct drbg_string *pers: personalization string to be used for
+ * initialization.
+ * * struct drbg_test_data *test: TEST parameter only -- should be NULL in
+ * normal use -- parameter sets predefined
+ * "entropy"
+ * The variable of flags is independent from the pers/perslen variables. If
+ * flags is set to 0 and perslen is set to 0, the current DRBG type is
+ * completely reset without using a personalization string.
+ *
+ * DRBG Usage
+ * ==========
+ * The SP 800-90A DRBG allows the user to specify a personalization string
+ * for initialization as well as an additional information string for each
+ * random number request. The following code fragments show how a caller
+ * uses the kernel crypto API to use the full functionality of the DRBG.
+ *
+ * Usage without any additional data
+ * ---------------------------------
+ * gcry_randomize(outbuf, OUTLEN, GCRY_STRONG_RANDOM);
+ *
+ *
+ * Usage with personalization string during initialization
+ * -------------------------------------------------------
+ * struct drbg_string pers;
+ * char personalization[11] = "some-string";
+ *
+ * drbg_string_fill(&pers, personalization, strlen(personalization));
+ * // The reset completely re-initializes the DRBG with the provided
+ * // personalization string without changing the DRBG type
+ * ret = gcry_control(GCRYCTL_DRBG_REINIT, 0, &pers, NULL);
+ * gcry_randomize(outbuf, OUTLEN, GCRY_STRONG_RANDOM);
+ *
+ *
+ * Usage with additional information string during random number request
+ * ---------------------------------------------------------------------
+ * struct drbg_string addtl;
+ * char addtl_string[11] = "some-string";
+ *
+ * drbg_string_fill(&addtl, addtl_string, strlen(addtl_string));
+ * // The following call is a wrapper to gcry_randomize() and returns
+ * // the same error codes.
+ * gcry_randomize_drbg(outbuf, OUTLEN, GCRY_STRONG_RANDOM, &addtl);
+ *
+ *
+ * Usage with personalization and additional information strings
+ * -------------------------------------------------------------
+ * Just mix both scenarios above.
+ *
+ *
+ * Switch the DRBG type to some other type
+ * ---------------------------------------
+ * // Switch to CTR DRBG AES-128 without prediction resistance
+ * ret = gcry_control(GCRYCTL_DRBG_REINIT, DRBG_NOPR_CTRAES128, NULL, NULL);
+ * gcry_randomize(outbuf, OUTLEN, GCRY_STRONG_RANDOM);
+ */
+
+#include <sys/types.h>
+#include <asm/types.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdint.h>
+
+#include <config.h>
+
+#include "g10lib.h"
+#include "random.h"
+#include "rand-internal.h"
+#include "../cipher/bithelp.h"
+
+/******************************************************************
+ * Common data structures
+ ******************************************************************/
+
+struct drbg_state;
+
+struct drbg_core
+{
+ u_int32_t flags; /* flags for the cipher */
+ __u8 statelen; /* maximum state length */
+ __u8 blocklen_bytes; /* block size of output in bytes */
+ int backend_cipher; /* libgcrypt backend cipher */
+};
+
+struct drbg_state_ops
+{
+ gpg_err_code_t (*update) (struct drbg_state * drbg,
+ struct drbg_string * seed, int reseed);
+ gpg_err_code_t (*generate) (struct drbg_state * drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string * addtl);
+};
+
+struct drbg_state
+{
+ unsigned char *V; /* internal state 10.1.1.1 1a) */
+ unsigned char *C; /* hash: static value 10.1.1.1 1b)
+ * hmac / ctr: key */
+ size_t reseed_ctr; /* Number of RNG requests since last reseed --
+ * 10.1.1.1 1c) */
+ unsigned char *scratchpad; /* some memory the DRBG can use for its
+ * operation -- allocated during init */
+ int seeded:1; /* DRBG fully seeded? */
+ int pr:1; /* Prediction resistance enabled? */
+ int fips_primed:1; /* Continuous test primed? */
+ unsigned char *prev; /* previous output value of drbg_blocklen for
+ * FIPS 140-2 continuous test */
+ /* Taken from libgcrypt ANSI X9.31 DRNG: We need to keep track of the
+ * process which did the initialization so that we can detect a fork.
+ * The volatile modifier is required so that the compiler does not
+ * optimize it away in case the getpid function is badly attributed. */
+ pid_t seed_init_pid;
+ const struct drbg_state_ops *d_ops;
+ const struct drbg_core *core;
+ struct drbg_test_data *test_data;
+};
+
+enum drbg_prefixes
+{
+ DRBG_PREFIX0 = 0x00,
+ DRBG_PREFIX1,
+ DRBG_PREFIX2,
+ DRBG_PREFIX3
+};
+
+#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
+
+/***************************************************************
+ * Backend cipher definitions available to DRBG
+ ***************************************************************/
+
+static const struct drbg_core drbg_cores[] = {
+ {
+ /* Hash DRBGs */
+ .flags = DRBG_HASHSHA1,
+ .statelen = 55, /* 440 bits */
+ .blocklen_bytes = 20,
+ .backend_cipher = GCRY_MD_SHA1,
+ },
+ {
+ .flags = DRBG_HASHSHA256,
+ .statelen = 55, /* 440 bits */
+ .blocklen_bytes = 32,
+ .backend_cipher = GCRY_MD_SHA256,
+ },
+ {
+ .flags = DRBG_HASHSHA384,
+ .statelen = 111, /* 888 bits */
+ .blocklen_bytes = 48,
+ .backend_cipher = GCRY_MD_SHA384,
+ },
+ {
+ .flags = DRBG_HASHSHA512,
+ .statelen = 111, /* 888 bits */
+ .blocklen_bytes = 64,
+ .backend_cipher = GCRY_MD_SHA512,
+ },
+ {
+ /* HMAC DRBGs */
+ .flags = DRBG_HASHSHA1 | DRBG_HMAC,
+ .statelen = 20, /* block length of cipher */
+ .blocklen_bytes = 20,
+ .backend_cipher = GCRY_MD_SHA1,
+ },
+ {
+ .flags = DRBG_HASHSHA256 | DRBG_HMAC,
+ .statelen = 32, /* block length of cipher */
+ .blocklen_bytes = 32,
+ .backend_cipher = GCRY_MD_SHA256,
+ },
+ {
+ .flags = DRBG_HASHSHA384 | DRBG_HMAC,
+ .statelen = 48, /* block length of cipher */
+ .blocklen_bytes = 48,
+ .backend_cipher = GCRY_MD_SHA384,
+ },
+ {
+ .flags = DRBG_HASHSHA512 | DRBG_HMAC,
+ .statelen = 64, /* block length of cipher */
+ .blocklen_bytes = 64,
+ .backend_cipher = GCRY_MD_SHA512,
+ },
+ {
+ /* block ciphers */
+ .flags = DRBG_CTRAES | DRBG_SYM128,
+ .statelen = 32, /* 256 bits as defined in 10.2.1 */
+ .blocklen_bytes = 16,
+ .backend_cipher = GCRY_CIPHER_AES128,
+ },
+ {
+ /* block ciphers */
+ .flags = DRBG_CTRAES | DRBG_SYM192,
+ .statelen = 40, /* 320 bits as defined in 10.2.1 */
+ .blocklen_bytes = 16,
+ .backend_cipher = GCRY_CIPHER_AES192,
+ },
+ {
+ /* block ciphers */
+ .flags = DRBG_CTRAES | DRBG_SYM256,
+ .statelen = 48, /* 384 bits as defined in 10.2.1 */
+ .blocklen_bytes = 16,
+ .backend_cipher = GCRY_CIPHER_AES256,
+ },
+};
+
+/******************************************************************
+ ******************************************************************
+ ******************************************************************
+ * Generic DRBG code
+ ******************************************************************
+ ******************************************************************
+ ******************************************************************/
+
+/******************************************************************
+ * Generic helper functions
+ ******************************************************************/
+
+#if 0
+#define dbg(x) do { log_debug x; } while(0)
+#else
+#define dbg(x)
+#endif
+
+int drbg_healthcheck (void);
+
+static inline void *
+drbg_malloc (size_t len)
+{
+ void *buf;
+ buf = xmalloc_secure (len);
+ if (buf)
+ memset (buf, 0, len);
+ return buf;
+}
+
+static inline __u8
+drbg_statelen (struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return drbg->core->statelen;
+ return 0;
+}
+
+static inline __u8
+drbg_blocklen (struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return drbg->core->blocklen_bytes;
+ return 0;
+}
+
+static inline __u8
+drbg_keylen (struct drbg_state *drbg)
+{
+ if (drbg && drbg->core)
+ return (drbg->core->statelen - drbg->core->blocklen_bytes);
+ return 0;
+}
+
+static inline size_t
+drbg_max_request_bytes (void)
+{
+ /* SP800-90A requires the limit 2**19 bits, but we return bytes */
+ return (1 << 16);
+}
+
+static inline size_t
+drbg_max_addtl (void)
+{
+ /* SP800-90A requires 2**35 bytes additional info str / pers str */
+#ifdef __LP64__
+ return (1UL<<35);
+#else
+ /*
+ * SP800-90A allows smaller maximum numbers to be returned -- we
+ * return SIZE_MAX - 1 to allow the verification of the enforcement
+ * of this value in drbg_healthcheck_sanity.
+ */
+ return (SIZE_MAX - 1);
+#endif
+}
+
+static inline size_t
+drbg_max_requests (void)
+{
+ /* SP800-90A requires 2**48 maximum requests before reseeding */
+#ifdef __LP64__
+ return (1UL<<48);
+#else
+ return SIZE_MAX;
+#endif
+}
+
+/*
+ * Return strength of DRBG according to SP800-90A section 8.4
+ *
+ * flags: DRBG flags reference
+ *
+ * Return: normalized strength value or 32 as a default to counter
+ * programming errors
+ */
+static inline unsigned short
+drbg_sec_strength (u_int32_t flags)
+{
+ if ((flags & DRBG_HASHSHA1) || (flags & DRBG_SYM128))
+ return 16;
+ else if (flags & DRBG_SYM192)
+ return 24;
+ else if ((flags & DRBG_SYM256) || (flags & DRBG_HASHSHA256) ||
+ (flags & DRBG_HASHSHA384) || (flags & DRBG_HASHSHA512))
+ return 32;
+ else
+ return 32;
+}
+
+/*
+ * FIPS 140-2 continuous self test
+ * The test is performed on the result of one round of the output
+ * function. Thus, the function implicitly knows the size of the
+ * buffer.
+ *
+ * @drbg DRBG handle
+ * @buf output buffer of random data to be checked
+ *
+ * return:
+ * false on error
+ * true on success
+ */
+static gpg_err_code_t
+drbg_fips_continuous_test (struct drbg_state *drbg, const unsigned char *buf)
+{
+ gpg_err_code_t ret = 0;
+ /* skip test if we test the overall system */
+ if (drbg->test_data)
+ return 1;
+ /* only perform test in FIPS mode */
+ if (0 == fips_mode ())
+ return 1;
+ if (!drbg->fips_primed)
+ {
+ /* Priming of FIPS test */
+ memcpy (drbg->prev, buf, drbg_blocklen (drbg));
+ drbg->fips_primed = 1;
+ /* return false due to priming, i.e. another round is needed */
+ return 0;
+ }
+ ret = memcmp (drbg->prev, buf, drbg_blocklen (drbg));
+ memcpy (drbg->prev, buf, drbg_blocklen (drbg));
+ /* the test shall pass when the two compared values are not equal */
+ return ret != 0;
+}
+
+static inline void drbg_cpu_to_be32(uint32_t val, unsigned char *buf)
+{
+ struct s {
+ uint32_t conv;
+ };
+ struct s *conversion = (struct s *) buf;
+
+ conversion->conv = be_bswap32(val);
+}
+
+static void
+drbg_add_buf (unsigned char *dst, size_t dstlen,
+ unsigned char *add, size_t addlen)
+{
+ /* implied: dstlen > addlen */
+ unsigned char *dstptr, *addptr;
+ unsigned int remainder = 0;
+ size_t len = addlen;
+
+ dstptr = dst + (dstlen - 1);
+ addptr = add + (addlen - 1);
+ while (len)
+ {
+ remainder += *dstptr + *addptr;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--;
+ dstptr--;
+ addptr--;
+ }
+ len = dstlen - addlen;
+ while (len && remainder > 0)
+ {
+ remainder = *dstptr + 1;
+ *dstptr = remainder & 0xff;
+ remainder >>= 8;
+ len--;
+ dstptr--;
+ }
+}
+
+/* Helper variables for read_cb().
+ *
+ * The _gcry_rnd*_gather_random interface does not allow to provide a
+ * data pointer. Thus we need to use a global variable for
+ * communication. However, the then required locking is anyway a good
+ * idea because it does not make sense to have several readers of (say
+ * /dev/random). It is easier to serve them one after the other. */
+static unsigned char *read_cb_buffer; /* The buffer. */
+static size_t read_cb_size; /* Size of the buffer. */
+static size_t read_cb_len; /* Used length. */
+
+/* Callback for generating seed from kernel device. */
+static void
+drbg_read_cb (const void *buffer, size_t length, enum random_origins origin)
+{
+ const unsigned char *p = buffer;
+
+ (void) origin;
+ gcry_assert (read_cb_buffer);
+
+ /* Note that we need to protect against gatherers returning more
+ * than the requested bytes (e.g. rndw32). */
+ while (length-- && read_cb_len < read_cb_size)
+ read_cb_buffer[read_cb_len++] = *p++;
+}
+
+static inline int
+drbg_get_entropy (struct drbg_state *drbg, unsigned char *buffer, size_t len)
+{
+ int rc = 0;
+
+ /* Perform testing as defined in 11.3.2 */
+ if (drbg->test_data && drbg->test_data->fail_seed_source)
+ return -1;
+
+ read_cb_buffer = buffer;
+ read_cb_size = len;
+ read_cb_len = 0;
+#if USE_RNDLINUX
+ rc = _gcry_rndlinux_gather_random (drbg_read_cb, 0, len,
+ GCRY_VERY_STRONG_RANDOM);
+#elif USE_RNDUNIX
+ rc = _gcry_rndunix_gather_random (read_cb, 0, length,
+ GCRY_VERY_STRONG_RANDOM);
+#elif USE_RNDW32
+ do
+ {
+ rc = _gcry_rndw32_gather_random (read_cb, 0, length,
+ GCRY_VERY_STRONG_RANDOM);
+ }
+ while (rc >= 0 && read_cb_len < read_cb_size);
+#else
+ rc = -1;
+#endif
+ return rc;
+}
+
+/******************************************************************
+ * CTR DRBG callback functions
+ ******************************************************************/
+
+static gpg_err_code_t drbg_gcry_sym (struct drbg_state *drbg,
+ const unsigned char *key,
+ unsigned char *outval,
+ const struct drbg_string *buf);
+
+/* BCC function for CTR DRBG as defined in 10.4.3 */
+static gpg_err_code_t
+drbg_ctr_bcc (struct drbg_state *drbg,
+ unsigned char *out, const unsigned char *key,
+ struct drbg_string *in)
+{
+ gpg_err_code_t ret = GPG_ERR_GENERAL;
+ struct drbg_string *curr = in;
+ size_t inpos = curr->len;
+ const unsigned char *pos = curr->buf;
+ struct drbg_string data;
+
+ drbg_string_fill (&data, out, drbg_blocklen (drbg));
+
+ /* 10.4.3 step 1 */
+ memset (out, 0, drbg_blocklen (drbg));
+
+ /* 10.4.3 step 2 / 4 */
+ while (inpos)
+ {
+ short cnt = 0;
+ /* 10.4.3 step 4.1 */
+ for (cnt = 0; cnt < drbg_blocklen (drbg); cnt++)
+ {
+ out[cnt] ^= *pos;
+ pos++;
+ inpos--;
+ /* the following branch implements the linked list
+ * iteration. If we are at the end of the current data
+ * set, we have to start using the next data set if
+ * available -- the inpos value always points to the
+ * current byte and will be zero if we have processed
+ * the last byte of the last linked list member */
+ if (0 == inpos)
+ {
+ curr = curr->next;
+ if (NULL != curr)
+ {
+ pos = curr->buf;
+ inpos = curr->len;
+ }
+ else
+ {
+ inpos = 0;
+ break;
+ }
+ }
+ }
+ /* 10.4.3 step 4.2 */
+ ret = drbg_gcry_sym (drbg, key, out, &data);
+ if (ret)
+ return ret;
+ /* 10.4.3 step 2 */
+ }
+ return 0;
+}
+
+
+/*
+ * scratchpad usage: drbg_ctr_update is interlinked with drbg_ctr_df
+ * (and drbg_ctr_bcc, but this function does not need any temporary buffers),
+ * the scratchpad is used as follows:
+ * drbg_ctr_update:
+ * temp
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * note: the cipher writing into this variable works
+ * blocklen-wise. Now, when the statelen is not a multiple
+ * of blocklen, the generateion loop below "spills over"
+ * by at most blocklen. Thus, we need to give sufficient
+ * memory.
+ * df_data
+ * start: drbg->scratchpad +
+ * drbg_statelen(drbg) + drbg_blocklen(drbg)
+ * length: drbg_statelen(drbg)
+ *
+ * drbg_ctr_df:
+ * pad
+ * start: df_data + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ * iv
+ * start: pad + drbg_blocklen(drbg)
+ * length: drbg_blocklen(drbg)
+ * temp
+ * start: iv + drbg_blocklen(drbg)
+ * length: drbg_satelen(drbg) + drbg_blocklen(drbg)
+ * note: temp is the buffer that the BCC function operates
+ * on. BCC operates blockwise. drbg_statelen(drbg)
+ * is sufficient when the DRBG state length is a multiple
+ * of the block size. For AES192 (and maybe other ciphers)
+ * this is not correct and the length for temp is
+ * insufficient (yes, that also means for such ciphers,
+ * the final output of all BCC rounds are truncated).
+ * Therefore, add drbg_blocklen(drbg) to cover all
+ * possibilities.
+ */
+
+/* Derivation Function for CTR DRBG as defined in 10.4.2 */
+static gpg_err_code_t
+drbg_ctr_df (struct drbg_state *drbg, unsigned char *df_data,
+ size_t bytes_to_return, struct drbg_string *addtl)
+{
+ gpg_err_code_t ret = GPG_ERR_GENERAL;
+ unsigned char L_N[8];
+ /* S3 is input */
+ struct drbg_string S1, S2, S4, cipherin;
+ struct drbg_string *tempstr = addtl;
+ unsigned char *pad = df_data + drbg_statelen (drbg);
+ unsigned char *iv = pad + drbg_blocklen (drbg);
+ unsigned char *temp = iv + drbg_blocklen (drbg);
+ size_t padlen = 0;
+ unsigned int templen = 0;
+ /* 10.4.2 step 7 */
+ unsigned int i = 0;
+ /* 10.4.2 step 8 */
+ const unsigned char *K = (unsigned char *)
+ "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"
+ "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
+ unsigned char *X;
+ size_t generated_len = 0;
+ size_t inputlen = 0;
+
+ memset (pad, 0, drbg_blocklen (drbg));
+ memset (iv, 0, drbg_blocklen (drbg));
+ memset (temp, 0, drbg_statelen (drbg));
+
+ /* 10.4.2 step 1 is implicit as we work byte-wise */
+
+ /* 10.4.2 step 2 */
+ if ((512 / 8) < bytes_to_return)
+ return GPG_ERR_INV_ARG;
+
+ /* 10.4.2 step 2 -- calculate the entire length of all input data */
+ for (; NULL != tempstr; tempstr = tempstr->next)
+ inputlen += tempstr->len;
+ drbg_cpu_to_be32 (inputlen, &L_N[0]);
+
+ /* 10.4.2 step 3 */
+ drbg_cpu_to_be32 (bytes_to_return, &L_N[4]);
+
+ /* 10.4.2 step 5: length is size of L_N, input_string, one byte, padding */
+ padlen = (inputlen + sizeof (L_N) + 1) % (drbg_blocklen (drbg));
+ /* wrap the padlen appropriately */
+ if (padlen)
+ padlen = drbg_blocklen (drbg) - padlen;
+ /* pad / padlen contains the 0x80 byte and the following zero bytes, so
+ * add one for byte for 0x80 */
+ padlen++;
+ pad[0] = 0x80;
+
+ /* 10.4.2 step 4 -- first fill the linked list and then order it */
+ drbg_string_fill (&S1, iv, drbg_blocklen (drbg));
+ drbg_string_fill (&S2, L_N, sizeof (L_N));
+ drbg_string_fill (&S4, pad, padlen);
+ S1.next = &S2;
+ S2.next = addtl;
+
+ /* Splice in addtl between S2 and S4 -- we place S4 at the end of the
+ * input data chain. As this code is only triggered when addtl is not
+ * NULL, no NULL checks are necessary.*/
+ tempstr = addtl;
+ while (tempstr->next)
+ tempstr = tempstr->next;
+ tempstr->next = &S4;
+
+ /* 10.4.2 step 9 */
+ while (templen < (drbg_keylen (drbg) + (drbg_blocklen (drbg))))
+ {
+ /* 10.4.2 step 9.1 - the padding is implicit as the buffer
+ * holds zeros after allocation -- even the increment of i
+ * is irrelevant as the increment remains within length of i */
+ drbg_cpu_to_be32 (i, iv);
+ /* 10.4.2 step 9.2 -- BCC and concatenation with temp */
+ ret = drbg_ctr_bcc (drbg, temp + templen, K, &S1);
+ if (ret)
+ goto out;
+ /* 10.4.2 step 9.3 */
+ i++;
+ templen += drbg_blocklen (drbg);
+ }
+
+ /* 10.4.2 step 11 */
+ /* implicit key len with seedlen - blocklen according to table 3 */
+ X = temp + (drbg_keylen (drbg));
+ drbg_string_fill (&cipherin, X, drbg_blocklen (drbg));
+
+ /* 10.4.2 step 12: overwriting of outval */
+
+ /* 10.4.2 step 13 */
+ while (generated_len < bytes_to_return)
+ {
+ short blocklen = 0;
+ /* 10.4.2 step 13.1 */
+ /* the truncation of the key length is implicit as the key
+ * is only drbg_blocklen in size -- check for the implementation
+ * of the cipher function callback */
+ ret = drbg_gcry_sym (drbg, temp, X, &cipherin);
+ if (ret)
+ goto out;
+ blocklen = (drbg_blocklen (drbg) <
+ (bytes_to_return - generated_len)) ?
+ drbg_blocklen (drbg) : (bytes_to_return - generated_len);
+ /* 10.4.2 step 13.2 and 14 */
+ memcpy (df_data + generated_len, X, blocklen);
+ generated_len += blocklen;
+ }
+
+ ret = 0;
+
+out:
+ memset (iv, 0, drbg_blocklen (drbg));
+ memset (temp, 0, drbg_statelen (drbg));
+ memset (pad, 0, drbg_blocklen (drbg));
+ return ret;
+}
+
+/*
+ * update function of CTR DRBG as defined in 10.2.1.2
+ *
+ * The reseed variable has an enhanced meaning compared to the update
+ * functions of the other DRBGs as follows:
+ * 0 => initial seed from initialization
+ * 1 => reseed via drbg_seed
+ * 2 => first invocation from drbg_ctr_update when addtl is present. In
+ * this case, the df_data scratchpad is not deleted so that it is
+ * available for another calls to prevent calling the DF function
+ * again.
+ * 3 => second invocation from drbg_ctr_update. When the update function
+ * was called with addtl, the df_data memory already contains the
+ * DFed addtl information and we do not need to call DF again.
+ */
+static gpg_err_code_t
+drbg_ctr_update (struct drbg_state *drbg,
+ struct drbg_string *addtl, int reseed)
+{
+ gpg_err_code_t ret = GPG_ERR_GENERAL;
+ /* 10.2.1.2 step 1 */
+ unsigned char *temp = drbg->scratchpad;
+ unsigned char *df_data = drbg->scratchpad + drbg_statelen (drbg) +
+ drbg_blocklen (drbg);
+ unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
+ unsigned int len = 0;
+ struct drbg_string cipherin;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset (temp, 0, drbg_statelen (drbg) + drbg_blocklen (drbg));
+ if (3 > reseed)
+ memset (df_data, 0, drbg_statelen (drbg));
+
+ /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
+ /* TODO use reseed variable to avoid re-doing DF operation */
+ (void) reseed;
+ if (addtl && 0 < addtl->len)
+ {
+ ret = drbg_ctr_df (drbg, df_data, drbg_statelen (drbg), addtl);
+ if (ret)
+ goto out;
+ }
+
+ drbg_string_fill (&cipherin, drbg->V, drbg_blocklen (drbg));
+ /* 10.2.1.3.2 step 2 and 3 -- are already covered as we memset(0)
+ * all memory during initialization */
+ while (len < (drbg_statelen (drbg)))
+ {
+ /* 10.2.1.2 step 2.1 */
+ drbg_add_buf (drbg->V, drbg_blocklen (drbg), &prefix, 1);
+ /* 10.2.1.2 step 2.2 */
+ /* using target of temp + len: 10.2.1.2 step 2.3 and 3 */
+ ret = drbg_gcry_sym (drbg, drbg->C, temp + len, &cipherin);
+ if (ret)
+ goto out;
+ /* 10.2.1.2 step 2.3 and 3 */
+ len += drbg_blocklen (drbg);
+ }
+
+ /* 10.2.1.2 step 4 */
+ temp_p = temp;
+ df_data_p = df_data;
+ for (len = 0; len < drbg_statelen (drbg); len++)
+ {
+ *temp_p ^= *df_data_p;
+ df_data_p++;
+ temp_p++;
+ }
+
+ /* 10.2.1.2 step 5 */
+ memcpy (drbg->C, temp, drbg_keylen (drbg));
+ /* 10.2.1.2 step 6 */
+ memcpy (drbg->V, temp + drbg_keylen (drbg), drbg_blocklen (drbg));
+ ret = 0;
+
+out:
+ memset (temp, 0, drbg_statelen (drbg) + drbg_blocklen (drbg));
+ if (2 != reseed)
+ memset (df_data, 0, drbg_statelen (drbg));
+ return ret;
+}
+
+/*
+ * scratchpad use: drbg_ctr_update is called independently from
+ * drbg_ctr_extract_bytes. Therefore, the scratchpad is reused
+ */
+/* Generate function of CTR DRBG as defined in 10.2.1.5.2 */
+static gpg_err_code_t
+drbg_ctr_generate (struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ gpg_err_code_t ret = 0;
+ unsigned int len = 0;
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset (drbg->scratchpad, 0, drbg_blocklen (drbg));
+
+ /* 10.2.1.5.2 step 2 */
+ if (addtl && 0 < addtl->len)
+ {
+ addtl->next = NULL;
+ ret = drbg_ctr_update (drbg, addtl, 2);
+ if (ret)
+ return ret;
+ }
+
+ /* 10.2.1.5.2 step 4.1 */
+ drbg_add_buf (drbg->V, drbg_blocklen (drbg), &prefix, 1);
+ drbg_string_fill (&data, drbg->V, drbg_blocklen (drbg));
+ while (len < buflen)
+ {
+ unsigned int outlen = 0;
+ /* 10.2.1.5.2 step 4.2 */
+ ret = drbg_gcry_sym (drbg, drbg->C, drbg->scratchpad, &data);
+ if (ret)
+ goto out;
+ outlen = (drbg_blocklen (drbg) < (buflen - len)) ?
+ drbg_blocklen (drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test (drbg, drbg->scratchpad))
+ {
+ /* 10.2.1.5.2 step 6 */
+ drbg_add_buf (drbg->V, drbg_blocklen (drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.2.1.5.2 step 4.3 */
+ memcpy (buf + len, drbg->scratchpad, outlen);
+ len += outlen;
+ /* 10.2.1.5.2 step 6 */
+ if (len < buflen)
+ drbg_add_buf (drbg->V, drbg_blocklen (drbg), &prefix, 1);
+ }
+
+ /* 10.2.1.5.2 step 6 */
+ if (addtl)
+ addtl->next = NULL;
+ ret = drbg_ctr_update (drbg, addtl, 3);
+
+out:
+ memset (drbg->scratchpad, 0, drbg_blocklen (drbg));
+ return ret;
+}
+
+static struct drbg_state_ops drbg_ctr_ops = {
+ .update = drbg_ctr_update,
+ .generate = drbg_ctr_generate,
+};
+
+/******************************************************************
+ * HMAC DRBG callback functions
+ ******************************************************************/
+
+static gpg_err_code_t drbg_gcry_hmac (struct drbg_state *drbg,
+ const unsigned char *key,
+ unsigned char *outval,
+ const struct drbg_string *buf);
+
+static gpg_err_code_t
+drbg_hmac_update (struct drbg_state *drbg,
+ struct drbg_string *seed, int reseed)
+{
+ gpg_err_code_t ret = GPG_ERR_GENERAL;
+ int i = 0;
+ struct drbg_string seed1, seed2, cipherin;
+
+ if (!reseed)
+ {
+ /* 10.1.2.3 step 2 already implicitly covered with
+ * the initial memset(0) of drbg->C */
+ memset (drbg->C, 0, drbg_statelen (drbg));
+ memset (drbg->V, 1, drbg_statelen (drbg));
+ }
+
+ /* build linked list which implements the concatenation and fill
+ * first part*/
+ drbg_string_fill (&seed1, drbg->V, drbg_statelen (drbg));
+ /* buffer will be filled in for loop below with one byte */
+ drbg_string_fill (&seed2, NULL, 1);
+ seed1.next = &seed2;
+ /* seed may be NULL */
+ seed2.next = seed;
+
+ drbg_string_fill (&cipherin, drbg->V, drbg_statelen (drbg));
+ /* we execute two rounds of V/K massaging */
+ for (i = 2; 0 < i; i--)
+ {
+ /* first round uses 0x0, second 0x1 */
+ unsigned char prefix = DRBG_PREFIX0;
+ if (1 == i)
+ prefix = DRBG_PREFIX1;
+ /* 10.1.2.2 step 1 and 4 -- concatenation and HMAC for key */
+ seed2.buf = &prefix;
+ ret = drbg_gcry_hmac (drbg, drbg->C, drbg->C, &seed1);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 2 and 5 -- HMAC for V */
+ ret = drbg_gcry_hmac (drbg, drbg->C, drbg->V, &cipherin);
+ if (ret)
+ return ret;
+
+ /* 10.1.2.2 step 3 */
+ if (!seed || 0 == seed->len)
+ return ret;
+ }
+ return 0;
+}
+
+/* generate function of HMAC DRBG as defined in 10.1.2.5 */
+static gpg_err_code_t
+drbg_hmac_generate (struct drbg_state *drbg,
+ unsigned char *buf,
+ unsigned int buflen, struct drbg_string *addtl)
+{
+ gpg_err_code_t ret = 0;
+ unsigned int len = 0;
+ struct drbg_string data;
+
+ /* 10.1.2.5 step 2 */
+ if (addtl && 0 < addtl->len)
+ {
+ addtl->next = NULL;
+ ret = drbg_hmac_update (drbg, addtl, 1);
+ if (ret)
+ return ret;
+ }
+
+ drbg_string_fill (&data, drbg->V, drbg_statelen (drbg));
+ while (len < buflen)
+ {
+ unsigned int outlen = 0;
+ /* 10.1.2.5 step 4.1 */
+ ret = drbg_gcry_hmac (drbg, drbg->C, drbg->V, &data);
+ if (ret)
+ return ret;
+ outlen = (drbg_blocklen (drbg) < (buflen - len)) ?
+ drbg_blocklen (drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test (drbg, drbg->V))
+ continue;
+
+ /* 10.1.2.5 step 4.2 */
+ memcpy (buf + len, drbg->V, outlen);
+ len += outlen;
+ }
+
+ /* 10.1.2.5 step 6 */
+ if (addtl)
+ addtl->next = NULL;
+ ret = drbg_hmac_update (drbg, addtl, 1);
+
+ return ret;
+}
+
+static struct drbg_state_ops drbg_hmac_ops = {
+ .update = drbg_hmac_update,
+ .generate = drbg_hmac_generate,
+};
+
+/******************************************************************
+ * Hash DRBG callback functions
+ ******************************************************************/
+
+/*
+ * scratchpad usage: as drbg_hash_update and drbg_hash_df are used
+ * interlinked, the scratchpad is used as follows:
+ * drbg_hash_update
+ * start: drbg->scratchpad
+ * length: drbg_statelen(drbg)
+ * drbg_hash_df:
+ * start: drbg->scratchpad + drbg_statelen(drbg)
+ * length: drbg_blocklen(drbg)
+ */
+/* Derivation Function for Hash DRBG as defined in 10.4.1 */
+static gpg_err_code_t
+drbg_hash_df (struct drbg_state *drbg,
+ unsigned char *outval, size_t outlen,
+ struct drbg_string *entropy)
+{
+ gpg_err_code_t ret = 0;
+ size_t len = 0;
+ unsigned char input[5];
+ unsigned char *tmp = drbg->scratchpad + drbg_statelen (drbg);
+ struct drbg_string data1;
+
+ memset (tmp, 0, drbg_blocklen (drbg));
+
+ /* 10.4.1 step 3 */
+ input[0] = 1;
+ drbg_cpu_to_be32 ((outlen * 8), &input[1]);
+
+ /* 10.4.1 step 4.1 -- concatenation of data for input into hash */
+ drbg_string_fill (&data1, input, 5);
+ data1.next = entropy;
+
+ /* 10.4.1 step 4 */
+ while (len < outlen)
+ {
+ short blocklen = 0;
+ /* 10.4.1 step 4.1 */
+ ret = drbg_gcry_hmac (drbg, NULL, tmp, &data1);
+ if (ret)
+ goto out;
+ /* 10.4.1 step 4.2 */
+ input[0]++;
+ blocklen = (drbg_blocklen (drbg) < (outlen - len)) ?
+ drbg_blocklen (drbg) : (outlen - len);
+ memcpy (outval + len, tmp, blocklen);
+ len += blocklen;
+ }
+
+out:
+ memset (tmp, 0, drbg_blocklen (drbg));
+ return ret;
+}
+
+/* update function for Hash DRBG as defined in 10.1.1.2 / 10.1.1.3 */
+static gpg_err_code_t
+drbg_hash_update (struct drbg_state *drbg, struct drbg_string *seed,
+ int reseed)
+{
+ gpg_err_code_t ret = 0;
+ struct drbg_string data1, data2;
+ unsigned char *V = drbg->scratchpad;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ memset (drbg->scratchpad, 0, drbg_statelen (drbg));
+ if (!seed)
+ return GPG_ERR_INV_ARG;
+
+ if (reseed)
+ {
+ /* 10.1.1.3 step 1: string length is concatenation of
+ * 1 byte, V and seed (which is concatenated entropy/addtl
+ * input)
+ */
+ memcpy (V, drbg->V, drbg_statelen (drbg));
+ drbg_string_fill (&data1, &prefix, 1);
+ drbg_string_fill (&data2, V, drbg_statelen (drbg));
+ data1.next = &data2;
+ data2.next = seed;
+ }
+ else
+ {
+ drbg_string_fill (&data1, seed->buf, seed->len);
+ data1.next = seed->next;
+ }
+
+ /* 10.1.1.2 / 10.1.1.3 step 2 and 3 */
+ ret = drbg_hash_df (drbg, drbg->V, drbg_statelen (drbg), &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- concatenation */
+ prefix = DRBG_PREFIX0;
+ drbg_string_fill (&data1, &prefix, 1);
+ drbg_string_fill (&data2, drbg->V, drbg_statelen (drbg));
+ data1.next = &data2;
+ /* 10.1.1.2 / 10.1.1.3 step 4 -- df operation */
+ ret = drbg_hash_df (drbg, drbg->C, drbg_statelen (drbg), &data1);
+
+out:
+ memset (drbg->scratchpad, 0, drbg_statelen (drbg));
+ return ret;
+}
+
+/* processing of additional information string for Hash DRBG */
+static gpg_err_code_t
+drbg_hash_process_addtl (struct drbg_state *drbg, struct drbg_string *addtl)
+{
+ gpg_err_code_t ret = 0;
+ struct drbg_string data1, data2;
+ struct drbg_string *data3;
+ unsigned char prefix = DRBG_PREFIX2;
+
+ /* this is value w as per documentation */
+ memset (drbg->scratchpad, 0, drbg_blocklen (drbg));
+
+ /* 10.1.1.4 step 2 */
+ if (!addtl || 0 == addtl->len)
+ return 0;
+
+ /* 10.1.1.4 step 2a -- concatenation */
+ drbg_string_fill (&data1, &prefix, 1);
+ drbg_string_fill (&data2, drbg->V, drbg_statelen (drbg));
+ data3 = addtl;
+ data1.next = &data2;
+ data2.next = data3;
+ data3->next = NULL;
+ /* 10.1.1.4 step 2a -- cipher invocation */
+ ret = drbg_gcry_hmac (drbg, NULL, drbg->scratchpad, &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.4 step 2b */
+ drbg_add_buf (drbg->V, drbg_statelen (drbg),
+ drbg->scratchpad, drbg_blocklen (drbg));
+
+out:
+ memset (drbg->scratchpad, 0, drbg_blocklen (drbg));
+ return ret;
+}
+
+/*
+ * Hashgen defined in 10.1.1.4
+ */
+static gpg_err_code_t
+drbg_hash_hashgen (struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen)
+{
+ gpg_err_code_t ret = 0;
+ unsigned int len = 0;
+ unsigned char *src = drbg->scratchpad;
+ unsigned char *dst = drbg->scratchpad + drbg_statelen (drbg);
+ struct drbg_string data;
+ unsigned char prefix = DRBG_PREFIX1;
+
+ /* use the scratchpad as a lookaside buffer */
+ memset (src, 0, drbg_statelen (drbg));
+ memset (dst, 0, drbg_blocklen (drbg));
+
+ /* 10.1.1.4 step hashgen 2 */
+ memcpy (src, drbg->V, drbg_statelen (drbg));
+
+ drbg_string_fill (&data, src, drbg_statelen (drbg));
+ while (len < buflen)
+ {
+ unsigned int outlen = 0;
+ /* 10.1.1.4 step hashgen 4.1 */
+ ret = drbg_gcry_hmac (drbg, NULL, dst, &data);
+ if (ret)
+ goto out;
+ outlen = (drbg_blocklen (drbg) < (buflen - len)) ?
+ drbg_blocklen (drbg) : (buflen - len);
+ if (!drbg_fips_continuous_test (drbg, dst))
+ {
+ drbg_add_buf (src, drbg_statelen (drbg), &prefix, 1);
+ continue;
+ }
+ /* 10.1.1.4 step hashgen 4.2 */
+ memcpy (buf + len, dst, outlen);
+ len += outlen;
+ /* 10.1.1.4 hashgen step 4.3 */
+ if (len < buflen)
+ drbg_add_buf (src, drbg_statelen (drbg), &prefix, 1);
+ }
+
+out:
+ memset (drbg->scratchpad, 0, (drbg_statelen (drbg) + drbg_blocklen (drbg)));
+ return ret;
+}
+
+/* generate function for Hash DRBG as defined in 10.1.1.4 */
+static gpg_err_code_t
+drbg_hash_generate (struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ gpg_err_code_t ret = 0;
+ unsigned char prefix = DRBG_PREFIX3;
+ struct drbg_string data1, data2;
+ union
+ {
+ unsigned char req[8];
+ uint64_t req_int;
+ } u;
+
+ /*
+ * scratchpad usage: drbg_hash_process_addtl uses the scratchpad, but
+ * fully completes before returning. Thus, we can reuse the scratchpad
+ */
+ /* 10.1.1.4 step 2 */
+ ret = drbg_hash_process_addtl (drbg, addtl);
+ if (ret)
+ return ret;
+ /* 10.1.1.4 step 3 -- invocation of the Hashgen function defined in
+ * 10.1.1.4 */
+ ret = drbg_hash_hashgen (drbg, buf, buflen);
+ if (ret)
+ return ret;
+
+ /* this is the value H as documented in 10.1.1.4 */
+ memset (drbg->scratchpad, 0, drbg_blocklen (drbg));
+ /* 10.1.1.4 step 4 */
+ drbg_string_fill (&data1, &prefix, 1);
+ drbg_string_fill (&data2, drbg->V, drbg_statelen (drbg));
+ data1.next = &data2;
+ ret = drbg_gcry_hmac (drbg, NULL, drbg->scratchpad, &data1);
+ if (ret)
+ goto out;
+
+ /* 10.1.1.4 step 5 */
+ drbg_add_buf (drbg->V, drbg_statelen (drbg),
+ drbg->scratchpad, drbg_blocklen (drbg));
+ drbg_add_buf (drbg->V, drbg_statelen (drbg), drbg->C, drbg_statelen (drbg));
+ u.req_int = be_bswap64(drbg->reseed_ctr);
+ drbg_add_buf (drbg->V, drbg_statelen (drbg), u.req, sizeof (u.req));
+
+out:
+ memset (drbg->scratchpad, 0, drbg_blocklen (drbg));
+ return ret;
+}
+
+/*
+ * scratchpad usage: as update and generate are used isolated, both
+ * can use the scratchpad
+ */
+static struct drbg_state_ops drbg_hash_ops = {
+ .update = drbg_hash_update,
+ .generate = drbg_hash_generate,
+};
+
+/******************************************************************
+ * Functions common for DRBG implementations
+ ******************************************************************/
+
+/*
+ * Seeding or reseeding of the DRBG
+ *
+ * @drbg: DRBG state struct
+ * @pers: personalization / additional information buffer
+ * @reseed: 0 for initial seed process, 1 for reseeding
+ *
+ * return:
+ * 0 on success
+ * error value otherwise
+ */
+static gpg_err_code_t
+drbg_seed (struct drbg_state *drbg, struct drbg_string *pers, int reseed)
+{
+ gpg_err_code_t ret = 0;
+ unsigned char *entropy = NULL;
+ size_t entropylen = 0;
+ struct drbg_string data1;
+
+ /* 9.1 / 9.2 / 9.3.1 step 3 */
+ if (pers && pers->len > (drbg_max_addtl ()))
+ {
+ dbg (("DRBG: personalization string too long %lu\n", pers->len));
+ return GPG_ERR_INV_ARG;
+ }
+ if (drbg->test_data && drbg->test_data->testentropy)
+ {
+ drbg_string_fill (&data1, drbg->test_data->testentropy->buf,
+ drbg->test_data->testentropy->len);
+ dbg (("DRBG: using test entropy\n"));
+ }
+ else
+ {
+ /* Gather entropy equal to the security strength of the DRBG.
+ * With a derivation function, a nonce is required in addition
+ * to the entropy. A nonce must be at least 1/2 of the security
+ * strength of the DRBG in size. Thus, entropy * nonce is 3/2
+ * of the strength. The consideration of a nonce is only
+ * applicable during initial seeding. */
+ entropylen = drbg_sec_strength (drbg->core->flags);
+ if (!entropylen)
+ return GPG_ERR_GENERAL;
+ if (0 == reseed)
+ /* make sure we round up strength/2 in
+ * case it is not divisible by 2 */
+ entropylen = ((entropylen + 1) / 2) * 3;
+ dbg (("DRBG: (re)seeding with %lu bytes of entropy\n", entropylen));
+ entropy = drbg_malloc (entropylen);
+ if (!entropy)
+ return GPG_ERR_ENOMEM;
+ ret = drbg_get_entropy (drbg, entropy, entropylen);
+ if (ret)
+ goto out;
+ drbg_string_fill (&data1, entropy, entropylen);
+ }
+
+ /* concatenation of entropy with personalization str / addtl input)
+ * the variable pers is directly handed by the caller, check its
+ * contents whether it is appropriate */
+ if (pers && pers->buf && 0 < pers->len && NULL == pers->next)
+ {
+ data1.next = pers;
+ dbg (("DRBG: using personalization string\n"));
+ }
+
+ ret = drbg->d_ops->update (drbg, &data1, reseed);
+ dbg (("DRBG: state updated with seed\n"));
+ if (ret)
+ goto out;
+ drbg->seeded = 1;
+ /* 10.1.1.2 / 10.1.1.3 step 5 */
+ drbg->reseed_ctr = 1;
+
+out:
+ if (entropy)
+ xfree (entropy);
+ return ret;
+}
+
+/*************************************************************************
+ * exported interfaces
+ *************************************************************************/
+
+/*
+ * DRBG generate function as required by SP800-90A - this function
+ * generates random numbers
+ *
+ * @drbg DRBG state handle
+ * @buf Buffer where to store the random numbers -- the buffer must already
+ * be pre-allocated by caller
+ * @buflen Length of output buffer - this value defines the number of random
+ * bytes pulled from DRBG
+ * @addtl Additional input that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ *
+ * return: generated number of bytes
+ */
+static gpg_err_code_t
+drbg_generate (struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ gpg_err_code_t ret = GPG_ERR_INV_ARG;
+
+ if (0 == buflen || !buf)
+ {
+ dbg (("DRBG: no buffer provided\n"));
+ return ret;
+ }
+ if (addtl && NULL == addtl->buf && 0 < addtl->len)
+ {
+ dbg (("DRBG: wrong format of additional information\n"));
+ return ret;
+ }
+
+ /* 9.3.1 step 2 */
+ if (buflen > (drbg_max_request_bytes ()))
+ {
+ dbg (("DRBG: requested random numbers too large %u\n", buflen));
+ return ret;
+ }
+ /* 9.3.1 step 3 is implicit with the chosen DRBG */
+ /* 9.3.1 step 4 */
+ if (addtl && addtl->len > (drbg_max_addtl ()))
+ {
+ dbg (("DRBG: additional information string too long %lu\n",
+ addtl->len));
+ return ret;
+ }
+ /* 9.3.1 step 5 is implicit with the chosen DRBG */
+ /* 9.3.1 step 6 and 9 supplemented by 9.3.2 step c -- the spec is a
+ * bit convoluted here, we make it simpler */
+ if ((drbg_max_requests ()) < drbg->reseed_ctr)
+ drbg->seeded = 0;
+
+ if (drbg->pr || !drbg->seeded)
+ {
+ dbg (("DRBG: reseeding before generation (prediction resistance: %s, state %s)\n", drbg->pr ? "true" : "false", drbg->seeded ? "seeded" : "unseeded"));
+ /* 9.3.1 steps 7.1 through 7.3 */
+ ret = drbg_seed (drbg, addtl, 1);
+ if (ret)
+ return ret;
+ /* 9.3.1 step 7.4 */
+ addtl = NULL;
+ }
+
+ if (addtl && addtl->buf)
+ {
+ dbg (("DRBG: using additional information string\n"));
+ }
+
+ /* 9.3.1 step 8 and 10 */
+ ret = drbg->d_ops->generate (drbg, buf, buflen, addtl);
+
+ /* 10.1.1.4 step 6, 10.1.2.5 step 7, 10.2.1.5.2 step 7 */
+ drbg->reseed_ctr++;
+ if (ret)
+ return ret;
+
+ /* 11.3.3 -- re-perform self tests after some generated random
+ * numbers, the chosen value after which self test is performed
+ * is arbitrary, but it should be reasonable */
+ /* Here we do not perform the self tests because of the following
+ * reasons: it is mathematically impossible that the initial self tests
+ * were successfully and the following are not. If the initial would
+ * pass and the following would not, the system integrity is violated.
+ * In this case, the entire system operation is questionable and it
+ * is unlikely that the integrity violation only affects to the
+ * correct operation of the DRBG.
+ */
+#if 0
+ if (drbg->reseed_ctr && !(drbg->reseed_ctr % 4096))
+ {
+ dbg (("DRBG: start to perform self test\n"));
+ ret = drbg_healthcheck ();
+ if (ret)
+ {
+ log_fatal (("DRBG: self test failed\n"));
+ return ret;
+ }
+ else
+ {
+ dbg (("DRBG: self test successful\n"));
+ }
+ }
+#endif
+
+ return ret;
+}
+
+/*
+ * Wrapper around drbg_generate which can pull arbitrary long strings
+ * from the DRBG without hitting the maximum request limitation.
+ *
+ * Parameters: see drbg_generate
+ * Return codes: see drbg_generate -- if one drbg_generate request fails,
+ * the entire drbg_generate_long request fails
+ */
+static gpg_err_code_t
+drbg_generate_long (struct drbg_state *drbg,
+ unsigned char *buf, unsigned int buflen,
+ struct drbg_string *addtl)
+{
+ gpg_err_code_t ret = 0;
+ unsigned int slice = 0;
+ unsigned char *buf_p = buf;
+ unsigned len = 0;
+ do
+ {
+ unsigned int chunk = 0;
+ slice = ((buflen - len) / drbg_max_request_bytes ());
+ chunk = slice ? drbg_max_request_bytes () : (buflen - len);
+ ret = drbg_generate (drbg, buf_p, chunk, addtl);
+ if (ret)
+ return ret;
+ buf_p += chunk;
+ len += chunk;
+ }
+ while (slice > 0 && (len < buflen));
+ return ret;
+}
+
+/*
+ * DRBG uninstantiate function as required by SP800-90A - this function
+ * frees all buffers and the DRBG handle
+ *
+ * @drbg DRBG state handle
+ *
+ * return
+ * 0 on success
+ */
+static gpg_err_code_t
+drbg_uninstantiate (struct drbg_state *drbg)
+{
+ if (!drbg)
+ return GPG_ERR_INV_ARG;
+ if (drbg->V)
+ xfree (drbg->V);
+ drbg->V = NULL;
+ if (drbg->C)
+ xfree (drbg->C);
+ drbg->C = NULL;
+ drbg->reseed_ctr = 0;
+ if (drbg->scratchpad)
+ xfree (drbg->scratchpad);
+ drbg->scratchpad = NULL;
+ drbg->seeded = 0;
+ drbg->pr = 0;
+ drbg->fips_primed = 0;
+ if (drbg->prev)
+ xfree (drbg->prev);
+ drbg->prev = NULL;
+ drbg->seed_init_pid = 0;
+ return 0;
+}
+
+/*
+ * DRBG instantiation function as required by SP800-90A - this function
+ * sets up the DRBG handle, performs the initial seeding and all sanity
+ * checks required by SP800-90A
+ *
+ * @drbg memory of state -- if NULL, new memory is allocated
+ * @pers Personalization string that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ * @coreref reference to core
+ * @flags Flags defining the requested DRBG type and cipher type. The flags
+ * are defined in drbg.h and may be XORed. Beware, if you XOR multiple
+ * cipher types together, the code picks the core on a first come first
+ * serve basis as it iterates through the available cipher cores and
+ * uses the one with the first match. The minimum required flags are:
+ * cipher type flag
+ *
+ * return
+ * 0 on success
+ * error value otherwise
+ */
+static gpg_err_code_t
+drbg_instantiate (struct drbg_state *drbg, struct drbg_string *pers,
+ int coreref, int pr)
+{
+ gpg_err_code_t ret = GPG_ERR_ENOMEM;
+ unsigned int sb_size = 0;
+
+ if (!drbg)
+ return GPG_ERR_INV_ARG;
+
+ dbg (("DRBG: Initializing DRBG core %d with prediction resistance %s\n",
+ coreref, pr ? "enabled" : "disabled"));
+ drbg->core = &drbg_cores[coreref];
+ drbg->pr = pr;
+ drbg->seeded = 0;
+ if (drbg->core->flags & DRBG_HMAC)
+ drbg->d_ops = &drbg_hmac_ops;
+ else if (drbg->core->flags & DRBG_HASH_MASK)
+ drbg->d_ops = &drbg_hash_ops;
+ else if (drbg->core->flags & DRBG_CTR_MASK)
+ drbg->d_ops = &drbg_ctr_ops;
+ else
+ return GPG_ERR_GENERAL;
+ /* 9.1 step 1 is implicit with the selected DRBG type -- see
+ * drbg_sec_strength() */
+
+ /* 9.1 step 2 is implicit as caller can select prediction resistance
+ * and the flag is copied into drbg->flags --
+ * all DRBG types support prediction resistance */
+
+ /* 9.1 step 4 is implicit in drbg_sec_strength */
+
+ /* no allocation of drbg as this is done by the kernel crypto API */
+ drbg->V = drbg_malloc (drbg_statelen (drbg));
+ if (!drbg->V)
+ goto err;
+ drbg->C = drbg_malloc (drbg_statelen (drbg));
+ if (!drbg->C)
+ goto err;
+ drbg->prev = drbg_malloc (drbg_blocklen (drbg));
+ if (!drbg->prev)
+ goto err;
+ drbg->fips_primed = 0;
+ /* scratchpad is only generated for CTR and Hash */
+ if (drbg->core->flags & DRBG_HMAC)
+ sb_size = 0;
+ else if (drbg->core->flags & DRBG_CTR_MASK)
+ sb_size = drbg_statelen (drbg) + drbg_blocklen (drbg) + /* temp */
+ drbg_statelen (drbg) + /* df_data */
+ drbg_blocklen (drbg) + /* pad */
+ drbg_blocklen (drbg) + /* iv */
+ drbg_statelen (drbg) + drbg_blocklen(drbg); /* temp */
+ else
+ sb_size = drbg_statelen (drbg) + drbg_blocklen (drbg);
+
+ if (0 < sb_size)
+ {
+ drbg->scratchpad = drbg_malloc (sb_size);
+ if (!drbg->scratchpad)
+ goto err;
+ }
+ dbg (("DRBG: state allocated with scratchpad size %u bytes\n", sb_size));
+
+ /* 9.1 step 6 through 11 */
+ ret = drbg_seed (drbg, pers, 0);
+ if (ret)
+ goto err;
+
+ dbg (("DRBG: core %d %s prediction resistance successfully initialized\n",
+ coreref, pr ? "with" : "without"));
+ return 0;
+
+err:
+ drbg_uninstantiate (drbg);
+ return ret;
+}
+
+/*
+ * DRBG reseed function as required by SP800-90A
+ *
+ * @drbg DRBG state handle
+ * @addtl Additional input that is mixed into state, may be NULL -- note
+ * the entropy is pulled by the DRBG internally unconditionally
+ * as defined in SP800-90A. The additional input is mixed into
+ * the state in addition to the pulled entropy.
+ *
+ * return
+ * 0 on success
+ * error value otherwise
+ */
+static gpg_err_code_t
+drbg_reseed (struct drbg_state *drbg, struct drbg_string *addtl)
+{
+ gpg_err_code_t ret = 0;
+ ret = drbg_seed (drbg, addtl, 1);
+ return ret;
+}
+
+/******************************************************************
+ * *****************************************************************
+ ******************************************************************
+ * libgcrypt integration code
+ ******************************************************************
+ ******************************************************************
+ ******************************************************************/
+
+/***************************************************************
+ * libgcrypt backend functions to the RNG API code
+ ***************************************************************/
+
+/* global state variable holding the current instance of the DRBG -- the
+ * default DRBG type is defined in _gcry_drbg_init */
+static struct drbg_state *gcry_drbg = NULL;
+GPGRT_LOCK_DEFINE (drbg_gcry_lock);
+
+static inline void
+drbg_lock (void)
+{
+ gpg_err_code_t rc;
+ rc = gpgrt_lock_lock (&drbg_gcry_lock);
+ if (rc)
+ log_fatal ("failed to acquire the RNG lock: %s\n", gpg_strerror (rc));
+}
+
+static inline void
+drbg_unlock (void)
+{
+ gpg_err_code_t rc;
+ rc = gpgrt_lock_unlock (&drbg_gcry_lock);
+ if (rc)
+ log_fatal ("failed to release the RNG lock: %s\n", gpg_strerror (rc));
+}
+
+/****** helper functions where lock must be held by caller *****/
+
+/* Check whether given flags are known to point to an applicable DRBG */
+static gpg_err_code_t
+drbg_algo_available (u_int32_t flags, int *coreref)
+{
+ int i = 0;
+ for (i = 0; ARRAY_SIZE (drbg_cores) > i; i++)
+ {
+ if ((drbg_cores[i].flags & DRBG_CIPHER_MASK) ==
+ (flags & DRBG_CIPHER_MASK))
+ {
+ *coreref = i;
+ return 0;
+ }
+ }
+ return GPG_ERR_GENERAL;
+}
+
+static gpg_err_code_t
+_gcry_drbg_init_internal (int full, u_int32_t flags, struct drbg_string *pers)
+{
+ gpg_err_code_t ret = 0;
+ static u_int32_t oldflags = 0;
+ int coreref = 0;
+ int pr = 0;
+ /* TODO what shall we do with the full variable? */
+ (void) full;
+
+ /* If a caller provides 0 as flags, use the flags of the previous
+ * initialization, otherwise use the current flags and remember them
+ * for the next invocation
+ */
+ if (0 == flags)
+ flags = oldflags;
+ else
+ oldflags = flags;
+
+ ret = drbg_algo_available (flags, &coreref);
+ if (ret)
+ return ret;
+
+ if (NULL != gcry_drbg)
+ {
+ drbg_uninstantiate (gcry_drbg);
+ }
+ else
+ {
+ gcry_drbg = drbg_malloc (sizeof (struct drbg_state));
+ if (!gcry_drbg)
+ return GPG_ERR_ENOMEM;
+ }
+ if (flags & DRBG_PREDICTION_RESIST)
+ pr = 1;
+ ret = drbg_instantiate (gcry_drbg, pers, coreref, pr);
+ if (ret)
+ fips_signal_error ("DRBG cannot be initialized");
+ else
+ gcry_drbg->seed_init_pid = getpid ();
+ return ret;
+}
+
+/************* calls available to common RNG code **************/
+
+/*
+ * Initialize one DRBG invoked by the libgcrypt API
+ *
+ * Function uses the kernel crypto API cra_name to look up
+ * the flags to instantiate the DRBG
+ */
+void
+_gcry_drbg_init (int full)
+{
+ /* default DRBG */
+ u_int32_t flags = DRBG_NOPR_HMACSHA256;
+ drbg_lock ();
+ _gcry_drbg_init_internal (full, flags, NULL);
+ drbg_unlock ();
+}
+
+/*
+ * Backend handler function for GCRYCTL_DRBG_REINIT
+ *
+ * Select a different DRBG type and initialize it.
+ * Function checks whether requested DRBG type exists and returns an error in
+ * case it does not. In case of an error, the previous instantiated DRBG is
+ * left untouched and alive. Thus, in case of an error, a DRBG is always
+ * available, even if it is not the chosen one.
+ *
+ * Re-initialization will be performed in any case regardless whether flags
+ * or personalization string are set.
+ *
+ * If flags == 0, do not change current DRBG
+ * If parsonalization string is NULL or its length is 0, re-initialize without
+ * personalization string
+ *
+ * If test_data is provided, the "entropy" is provided instead of using
+ * the noise source.
+ */
+gpg_err_code_t
+_gcry_drbg_reinit (u_int32_t flags, struct drbg_string *pers,
+ struct drbg_test_data *test_data)
+{
+ gpg_err_code_t ret = GPG_ERR_GENERAL;
+ dbg (("DRBG: reinitialize internal DRBG state with flags %u\n", flags));
+ drbg_lock ();
+ gcry_drbg->test_data = test_data;
+ ret = _gcry_drbg_init_internal (1, flags, pers);
+ drbg_unlock ();
+ return ret;
+}
+
+/* Try to close the FDs of the random gather module. This is
+ * currently only implemented for rndlinux. */
+void
+_gcry_drbg_close_fds (void)
+{
+#if USE_RNDLINUX
+ drbg_lock ();
+ _gcry_rndlinux_gather_random (NULL, 0, 0, 0);
+ drbg_unlock ();
+#endif
+}
+
+/* Print some statistics about the RNG. */
+void
+_gcry_drbg_dump_stats (void)
+{
+ /* Not yet implemented. */
+ /* Maybe dumping of reseed counter? */
+}
+
+/* This function returns true if no real RNG is available or the
+ * quality of the RNG has been degraded for test purposes. */
+int
+_gcry_drbg_is_faked (void)
+{
+ return 0; /* Faked random is not allowed. */
+}
+
+/* Add BUFLEN bytes from BUF to the internal random pool. QUALITY
+ * should be in the range of 0..100 to indicate the goodness of the
+ * entropy added, or -1 for goodness not known. */
+gcry_error_t
+_gcry_drng_add_bytes (const void *buf, size_t buflen, int quality)
+{
+ gpg_err_code_t ret = 0;
+ struct drbg_string seed;
+ (void) quality;
+ if (NULL == gcry_drbg)
+ return GPG_ERR_GENERAL;
+ drbg_string_fill (&seed, (unsigned char *) buf, buflen);
+ drbg_lock ();
+ ret = drbg_reseed (gcry_drbg, &seed);
+ drbg_unlock ();
+ return ret;
+}
+
+/* This function is to be used for all types of random numbers, including
+ * nonces
+ */
+void
+_gcry_drbg_randomize (void *buffer, size_t length,
+ enum gcry_random_level level)
+{
+ (void) level;
+ drbg_lock ();
+ if (NULL == gcry_drbg)
+ {
+ fips_signal_error ("DRBG is not initialized");
+ goto bailout;
+ }
+
+ /* As reseeding changes the entire state of the DRBG, including any
+ * key, either a re-init or a reseed is sufficient for a fork */
+ if (gcry_drbg->seed_init_pid != getpid ())
+ {
+ /* We are in a child of us. Perform a reseeding. */
+ if (drbg_reseed (gcry_drbg, NULL))
+ {
+ fips_signal_error ("reseeding upon fork failed");
+ log_fatal ("severe error getting random\n");
+ goto bailout;
+ }
+ }
+ /* potential integer overflow is covered by drbg_generate which
+ * ensures that length cannot overflow an unsigned int */
+ if (0 < length)
+ {
+ if (!buffer)
+ goto bailout;
+ if (drbg_generate_long (gcry_drbg, buffer, (unsigned int) length, NULL))
+ log_fatal ("No random numbers generated\n");
+ }
+ else
+ {
+ struct drbg_gen *data = (struct drbg_gen *) buffer;
+ /* catch NULL pointer */
+ if (!data || !data->outbuf)
+ {
+ fips_signal_error ("No output buffer provided");
+ goto bailout;
+ }
+ gcry_drbg->test_data = data->test_data;
+ if (drbg_generate_long (gcry_drbg, data->outbuf, data->outlen,
+ data->addtl))
+ log_fatal ("No random numbers generated\n");
+ }
+bailout:
+ drbg_unlock ();
+ return;
+
+}
+
+/***************************************************************
+ * Self-test code
+ ***************************************************************/
+
+/*
+ * Test vectors from
+ * http://csrc.nist.gov/groups/STM/cavp/documents/drbg/drbgtestvectors.zip
+ */
+
+struct drbg_test_vector
+{
+ u_int32_t flags;
+ unsigned char *entropy;
+ size_t entropylen;
+ unsigned char *entpra;
+ unsigned char *entprb;
+ size_t entprlen;
+ unsigned char *addtla;
+ unsigned char *addtlb;
+ size_t addtllen;
+ unsigned char *pers;
+ size_t perslen;
+ unsigned char *expected;
+ size_t expectedlen;
+};
+
+struct drbg_test_vector drbg_test_pr[] = {
+ {
+ .flags = (DRBG_PR_HASHSHA256),
+ .entropy = (unsigned char *)
+ "\x5d\xf2\x14\xbc\xf6\xb5\x4e\x0b\xf0\x0d\x6f\x2d"
+ "\xe2\x01\x66\x7b\xd0\xa4\x73\xa4\x21\xdd\xb0\xc0"
+ "\x51\x79\x09\xf4\xea\xa9\x08\xfa\xa6\x67\xe0\xe1"
+ "\xd1\x88\xa8\xad\xee\x69\x74\xb3\x55\x06\x9b\xf6",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\xef\x48\x06\xa2\xc2\x45\xf1\x44\xfa\x34\x2c\xeb"
+ "\x8d\x78\x3c\x09\x8f\x34\x72\x20\xf2\xe7\xfd\x13"
+ "\x76\x0a\xf6\xdc\x3c\xf5\xc0\x15",
+ .entprb = (unsigned char *)
+ "\x4b\xbe\xe5\x24\xed\x6a\x2d\x0c\xdb\x73\x5e\x09"
+ "\xf9\xad\x67\x7c\x51\x47\x8b\x6b\x30\x2a\xc6\xde"
+ "\x76\xaa\x55\x04\x8b\x0a\x72\x95",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\x3b\x14\x71\x99\xa1\xda\xa0\x42\xe6\xc8\x85\x32"
+ "\x70\x20\x32\x53\x9a\xbe\xd1\x1e\x15\xef\xfb\x4c"
+ "\x25\x6e\x19\x3a\xf0\xb9\xcb\xde\xf0\x3b\xc6\x18"
+ "\x4d\x85\x5a\x9b\xf1\xe3\xc2\x23\x03\x93\x08\xdb"
+ "\xa7\x07\x4b\x33\x78\x40\x4d\xeb\x24\xf5\x6e\x81"
+ "\x4a\x1b\x6e\xa3\x94\x52\x43\xb0\xaf\x2e\x21\xf4"
+ "\x42\x46\x8e\x90\xed\x34\x21\x75\xea\xda\x67\xb6"
+ "\xe4\xf6\xff\xc6\x31\x6c\x9a\x5a\xdb\xb3\x97\x13"
+ "\x09\xd3\x20\x98\x33\x2d\x6d\xd7\xb5\x6a\xa8\xa9"
+ "\x9a\x5b\xd6\x87\x52\xa1\x89\x2b\x4b\x9c\x64\x60"
+ "\x50\x47\xa3\x63\x81\x16\xaf\x19",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\xbe\x13\xdb\x2a\xe9\xa8\xfe\x09\x97\xe1\xce\x5d"
+ "\xe8\xbb\xc0\x7c\x4f\xcb\x62\x19\x3f\x0f\xd2\xad"
+ "\xa9\xd0\x1d\x59\x02\xc4\xff\x70",
+ .addtlb = (unsigned char *)
+ "\x6f\x96\x13\xe2\xa7\xf5\x6c\xfe\xdf\x66\xe3\x31"
+ "\x63\x76\xbf\x20\x27\x06\x49\xf1\xf3\x01\x77\x41"
+ "\x9f\xeb\xe4\x38\xfe\x67\x00\xcd",
+ .addtllen = 32,
+ .pers = NULL,
+ .perslen = 0,
+ },
+ {
+ .flags = (DRBG_PR_HMACSHA256),
+ .entropy = (unsigned char *)
+ "\x13\x54\x96\xfc\x1b\x7d\x28\xf3\x18\xc9\xa7\x89"
+ "\xb6\xb3\xc8\x72\xac\x00\xd4\x59\x36\x25\x05\xaf"
+ "\xa5\xdb\x96\xcb\x3c\x58\x46\x87\xa5\xaa\xbf\x20"
+ "\x3b\xfe\x23\x0e\xd1\xc7\x41\x0f\x3f\xc9\xb3\x67",
+ .entropylen = 48,
+ .entpra = (unsigned char *)
+ "\xe2\xbd\xb7\x48\x08\x06\xf3\xe1\x93\x3c\xac\x79"
+ "\xa7\x2b\x11\xda\xe3\x2e\xe1\x91\xa5\x02\x19\x57"
+ "\x20\x28\xad\xf2\x60\xd7\xcd\x45",
+ .entprb = (unsigned char *)
+ "\x8b\xd4\x69\xfc\xff\x59\x95\x95\xc6\x51\xde\x71"
+ "\x68\x5f\xfc\xf9\x4a\xab\xec\x5a\xcb\xbe\xd3\x66"
+ "\x1f\xfa\x74\xd3\xac\xa6\x74\x60",
+ .entprlen = 32,
+ .expected = (unsigned char *)
+ "\x1f\x9e\xaf\xe4\xd2\x46\xb7\x47\x41\x4c\x65\x99"
+ "\x01\xe9\x3b\xbb\x83\x0c\x0a\xb0\xc1\x3a\xe2\xb3"
+ "\x31\x4e\xeb\x93\x73\xee\x0b\x26\xc2\x63\xa5\x75"
+ "\x45\x99\xd4\x5c\x9f\xa1\xd4\x45\x87\x6b\x20\x61"
+ "\x40\xea\x78\xa5\x32\xdf\x9e\x66\x17\xaf\xb1\x88"
+ "\x9e\x2e\x23\xdd\xc1\xda\x13\x97\x88\xa5\xb6\x5e"
+ "\x90\x14\x4e\xef\x13\xab\x5c\xd9\x2c\x97\x9e\x7c"
+ "\xd7\xf8\xce\xea\x81\xf5\xcd\x71\x15\x49\x44\xce"
+ "\x83\xb6\x05\xfb\x7d\x30\xb5\x57\x2c\x31\x4f\xfc"
+ "\xfe\x80\xb6\xc0\x13\x0c\x5b\x9b\x2e\x8f\x3d\xfc"
+ "\xc2\xa3\x0c\x11\x1b\x80\x5f\xf3",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = (unsigned char *)
+ "\x64\xb6\xfc\x60\xbc\x61\x76\x23\x6d\x3f\x4a\x0f"
+ "\xe1\xb4\xd5\x20\x9e\x70\xdd\x03\x53\x6d\xbf\xce"
+ "\xcd\x56\x80\xbc\xb8\x15\xc8\xaa",
+ .perslen = 32,
+ },
+ {
+ .flags = (DRBG_PR_CTRAES128),
+ .entropy = (unsigned char *)
+ "\x92\x89\x8f\x31\xfa\x1c\xff\x6d\x18\x2f\x26\x06"
+ "\x43\xdf\xf8\x18\xc2\xa4\xd9\x72\xc3\xb9\xb6\x97",
+ .entropylen = 24,
+ .entpra = (unsigned char *)
+ "\x20\x72\x8a\x06\xf8\x6f\x8d\xd4\x41\xe2\x72\xb7"
+ "\xc4\x2c\xe8\x10",
+ .entprb = (unsigned char *)
+ "\x3d\xb0\xf0\x94\xf3\x05\x50\x33\x17\x86\x3e\x22"
+ "\x08\xf7\xa5\x01",
+ .entprlen = 16,
+ .expected = (unsigned char *)
+ "\x5a\x35\x39\x87\x0f\x4d\x22\xa4\x09\x24\xee\x71"
+ "\xc9\x6f\xac\x72\x0a\xd6\xf0\x88\x82\xd0\x83\x28"
+ "\x73\xec\x3f\x93\xd8\xab\x45\x23\xf0\x7e\xac\x45"
+ "\x14\x5e\x93\x9f\xb1\xd6\x76\x43\x3d\xb6\xe8\x08"
+ "\x88\xf6\xda\x89\x08\x77\x42\xfe\x1a\xf4\x3f\xc4"
+ "\x23\xc5\x1f\x68",
+ .expectedlen = 64,
+ .addtla = (unsigned char *)
+ "\x1a\x40\xfa\xe3\xcc\x6c\x7c\xa0\xf8\xda\xba\x59"
+ "\x23\x6d\xad\x1d",
+ .addtlb = (unsigned char *)
+ "\x9f\x72\x76\x6c\xc7\x46\xe5\xed\x2e\x53\x20\x12"
+ "\xbc\x59\x31\x8c",
+ .addtllen = 16,
+ .pers = (unsigned char *)
+ "\xea\x65\xee\x60\x26\x4e\x7e\xb6\x0e\x82\x68\xc4"
+ "\x37\x3c\x5c\x0b",
+ .perslen = 16,
+ },
+};
+
+struct drbg_test_vector drbg_test_nopr[] = {
+ {
+ .flags = DRBG_NOPR_HASHSHA256,
+ .entropy = (unsigned char *)
+ "\x73\xd3\xfb\xa3\x94\x5f\x2b\x5f\xb9\x8f\xf6\x9c"
+ "\x8a\x93\x17\xae\x19\xc3\x4c\xc3\xd6\xca\xa3\x2d"
+ "\x16\xfc\x42\xd2\x2d\xd5\x6f\x56\xcc\x1d\x30\xff"
+ "\x9e\x06\x3e\x09\xce\x58\xe6\x9a\x35\xb3\xa6\x56",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\x71\x7b\x93\x46\x1a\x40\xaa\x35\xa4\xaa\xc5\xe7"
+ "\x6d\x5b\x5b\x8a\xa0\xdf\x39\x7d\xae\x71\x58\x5b"
+ "\x3c\x7c\xb4\xf0\x89\xfa\x4a\x8c\xa9\x5c\x54\xc0"
+ "\x40\xdf\xbc\xce\x26\x81\x34\xf8\xba\x7d\x1c\xe8"
+ "\xad\x21\xe0\x74\xcf\x48\x84\x30\x1f\xa1\xd5\x4f"
+ "\x81\x42\x2f\xf4\xdb\x0b\x23\xf8\x73\x27\xb8\x1d"
+ "\x42\xf8\x44\x58\xd8\x5b\x29\x27\x0a\xf8\x69\x59"
+ "\xb5\x78\x44\xeb\x9e\xe0\x68\x6f\x42\x9a\xb0\x5b"
+ "\xe0\x4e\xcb\x6a\xaa\xe2\xd2\xd5\x33\x25\x3e\xe0"
+ "\x6c\xc7\x6a\x07\xa5\x03\x83\x9f\xe2\x8b\xd1\x1c"
+ "\x70\xa8\x07\x59\x97\xeb\xf6\xbe",
+ .expectedlen = 128,
+ .addtla = (unsigned char *)
+ "\xf4\xd5\x98\x3d\xa8\xfc\xfa\x37\xb7\x54\x67\x73"
+ "\xc7\xc3\xdd\x47\x34\x71\x02\x5d\xc1\xa0\xd3\x10"
+ "\xc1\x8b\xbd\xf5\x66\x34\x6f\xdd",
+ .addtlb = (unsigned char *)
+ "\xf7\x9e\x6a\x56\x0e\x73\xe9\xd9\x7a\xd1\x69\xe0"
+ "\x6f\x8c\x55\x1c\x44\xd1\xce\x6f\x28\xcc\xa4\x4d"
+ "\xa8\xc0\x85\xd1\x5a\x0c\x59\x40",
+ .addtllen = 32,
+ .pers = NULL,
+ .perslen = 0,
+ },
+ {
+ .flags = DRBG_NOPR_HMACSHA256,
+ .entropy = (unsigned char *)
+ "\x8d\xf0\x13\xb4\xd1\x03\x52\x30\x73\x91\x7d\xdf"
+ "\x6a\x86\x97\x93\x05\x9e\x99\x43\xfc\x86\x54\x54"
+ "\x9e\x7a\xb2\x2f\x7c\x29\xf1\x22\xda\x26\x25\xaf"
+ "\x2d\xdd\x4a\xbc\xce\x3c\xf4\xfa\x46\x59\xd8\x4e",
+ .entropylen = 48,
+ .expected = (unsigned char *)
+ "\xb9\x1c\xba\x4c\xc8\x4f\xa2\x5d\xf8\x61\x0b\x81"
+ "\xb6\x41\x40\x27\x68\xa2\x09\x72\x34\x93\x2e\x37"
+ "\xd5\x90\xb1\x15\x4c\xbd\x23\xf9\x74\x52\xe3\x10"
+ "\xe2\x91\xc4\x51\x46\x14\x7f\x0d\xa2\xd8\x17\x61"
+ "\xfe\x90\xfb\xa6\x4f\x94\x41\x9c\x0f\x66\x2b\x28"
+ "\xc1\xed\x94\xda\x48\x7b\xb7\xe7\x3e\xec\x79\x8f"
+ "\xbc\xf9\x81\xb7\x91\xd1\xbe\x4f\x17\x7a\x89\x07"
+ "\xaa\x3c\x40\x16\x43\xa5\xb6\x2b\x87\xb8\x9d\x66"
+ "\xb3\xa6\x0e\x40\xd4\xa8\xe4\xe9\xd8\x2a\xf6\xd2"
+ "\x70\x0e\x6f\x53\x5c\xdb\x51\xf7\x5c\x32\x17\x29"
+ "\x10\x37\x41\x03\x0c\xcc\x3a\x56",
+ .expectedlen = 128,
+ .addtla = NULL,
+ .addtlb = NULL,
+ .addtllen = 0,
+ .pers = (unsigned char *)
+ "\xb5\x71\xe6\x6d\x7c\x33\x8b\xc0\x7b\x76\xad\x37"
+ "\x57\xbb\x2f\x94\x52\xbf\x7e\x07\x43\x7a\xe8\x58"
+ "\x1c\xe7\xbc\x7c\x3a\xc6\x51\xa9",
+ .perslen = 32,
+ },
+ {
+ .flags = DRBG_NOPR_CTRAES128,
+ .entropy = (unsigned char *)
+ "\xc0\x70\x1f\x92\x50\x75\x8f\xcd\xf2\xbe\x73\x98"
+ "\x80\xdb\x66\xeb\x14\x68\xb4\xa5\x87\x9c\x2d\xa6",
+ .entropylen = 24,
+ .expected = (unsigned char *)
+ "\x97\xc0\xc0\xe5\xa0\xcc\xf2\x4f\x33\x63\x48\x8a"
+ "\xdb\x13\x0a\x35\x89\xbf\x80\x65\x62\xee\x13\x95"
+ "\x7c\x33\xd3\x7d\xf4\x07\x77\x7a\x2b\x65\x0b\x5f"
+ "\x45\x5c\x13\xf1\x90\x77\x7f\xc5\x04\x3f\xcc\x1a"
+ "\x38\xf8\xcd\x1b\xbb\xd5\x57\xd1\x4a\x4c\x2e\x8a"
+ "\x2b\x49\x1e\x5c",
+ .expectedlen = 64,
+ .addtla = (unsigned char *)
+ "\xf9\x01\xf8\x16\x7a\x1d\xff\xde\x8e\x3c\x83\xe2"
+ "\x44\x85\xe7\xfe",
+ .addtlb = (unsigned char *)
+ "\x17\x1c\x09\x38\xc2\x38\x9f\x97\x87\x60\x55\xb4"
+ "\x82\x16\x62\x7f",
+ .addtllen = 16,
+ .pers = (unsigned char *)
+ "\x80\x08\xae\xe8\xe9\x69\x40\xc5\x08\x73\xc7\x9f"
+ "\x8e\xcf\xe0\x02",
+ .perslen = 16,
+ },
+};
+
+
+/*
+ * Tests implement the CAVS test approach as documented in
+ * http://csrc.nist.gov/groups/STM/cavp/documents/drbg/DRBGVS.pdf
+ */
+
+/*
+ * CAVS test
+ */
+static gpg_err_code_t
+drbg_healthcheck_one (struct drbg_test_vector *test)
+{
+ gpg_err_code_t ret = GPG_ERR_ENOMEM;
+ struct drbg_state *drbg = NULL;
+ struct drbg_test_data test_data;
+ struct drbg_string addtl, pers, testentropy;
+ int coreref = 0;
+ int pr = 0;
+ unsigned char *buf = drbg_malloc (test->expectedlen);
+
+ if (!buf)
+ return GPG_ERR_ENOMEM;
+ ret = drbg_algo_available (test->flags, &coreref);
+ if (ret)
+ goto outbuf;
+
+ drbg = drbg_malloc (sizeof (struct drbg_state));
+ if (!drbg)
+ goto outbuf;
+
+ if (test->flags & DRBG_PREDICTION_RESIST)
+ pr = 1;
+
+ test_data.testentropy = &testentropy;
+ drbg_string_fill (&testentropy, test->entropy, test->entropylen);
+ drbg->test_data = &test_data;
+ drbg_string_fill (&pers, test->pers, test->perslen);
+ ret = drbg_instantiate (drbg, &pers, coreref, pr);
+ if (ret)
+ goto outbuf;
+
+ drbg_string_fill (&addtl, test->addtla, test->addtllen);
+ if (test->entpra)
+ {
+ drbg_string_fill (&testentropy, test->entpra, test->entprlen);
+ drbg->test_data = &test_data;
+ }
+ drbg_generate_long (drbg, buf, test->expectedlen, &addtl);
+
+ drbg_string_fill (&addtl, test->addtlb, test->addtllen);
+ if (test->entprb)
+ {
+ drbg_string_fill (&testentropy, test->entprb, test->entprlen);
+ drbg->test_data = &test_data;
+ }
+ drbg_generate_long (drbg, buf, test->expectedlen, &addtl);
+
+ ret = memcmp (test->expected, buf, test->expectedlen);
+
+ drbg_uninstantiate (drbg);
+outbuf:
+ xfree (buf);
+ if (drbg)
+ xfree (drbg);
+ return ret;
+}
+
+/*
+ * Tests as defined in 11.3.2 in addition to the cipher tests: testing
+ * of the error handling.
+ *
+ * Note, testing the reseed counter is not done as an automatic reseeding
+ * is performed in drbg_generate when the reseed counter is too large.
+ */
+static gpg_err_code_t
+drbg_healthcheck_sanity (struct drbg_test_vector *test)
+{
+ unsigned int len = 0;
+ struct drbg_state *drbg = NULL;
+ gpg_err_code_t ret = GPG_ERR_GENERAL;
+ gpg_err_code_t tmpret = GPG_ERR_GENERAL;
+ struct drbg_test_data test_data;
+ struct drbg_string addtl, testentropy;
+ int coreref = 0;
+ unsigned char *buf = NULL;
+ size_t max_addtllen, max_request_bytes;
+
+ /* only perform test in FIPS mode */
+ if (0 == fips_mode ())
+ return 0;
+
+ buf = drbg_malloc (test->expectedlen);
+ if (!buf)
+ return GPG_ERR_ENOMEM;
+ tmpret = drbg_algo_available (test->flags, &coreref);
+ if (tmpret)
+ goto outbuf;
+ drbg = drbg_malloc (sizeof (struct drbg_state));
+ if (!drbg)
+ goto outbuf;
+
+ /* if the following tests fail, it is likely that there is a buffer
+ * overflow and we get a SIGSEV */
+ ret = drbg_instantiate (drbg, NULL, coreref, 1);
+ if (ret)
+ goto outbuf;
+ max_addtllen = drbg_max_addtl ();
+ max_request_bytes = drbg_max_request_bytes ();
+ /* overflow addtllen with additonal info string */
+ drbg_string_fill (&addtl, test->addtla, (max_addtllen + 1));
+ len = drbg_generate (drbg, buf, test->expectedlen, &addtl);
+ if (len)
+ goto outdrbg;
+
+ /* overflow max_bits */
+ len = drbg_generate (drbg, buf, (max_request_bytes + 1), NULL);
+ if (len)
+ goto outdrbg;
+ drbg_uninstantiate (drbg);
+
+ /* test failing entropy source as defined in 11.3.2 */
+ test_data.testentropy = NULL;
+ test_data.fail_seed_source = 1;
+ drbg->test_data = &test_data;
+ tmpret = drbg_instantiate (drbg, NULL, coreref, 0);
+ if (!tmpret)
+ goto outdrbg;
+ test_data.fail_seed_source = 0;
+
+ test_data.testentropy = &testentropy;
+ drbg_string_fill (&testentropy, test->entropy, test->entropylen);
+ /* overflow max addtllen with personalization string */
+ tmpret = drbg_instantiate (drbg, &addtl, coreref, 0);
+ if (!tmpret)
+ goto outdrbg;
+
+ /* test uninstantated DRBG */
+ len = drbg_generate (drbg, buf, (max_request_bytes + 1), NULL);
+ if (len)
+ goto outbuf;
+
+ dbg (("DRBG: Sanity tests for failure code paths successfully completed\n"));
+ ret = 0;
+
+outdrbg:
+ drbg_uninstantiate (drbg);
+outbuf:
+ xfree (buf);
+ if (drbg)
+ xfree (drbg);
+ return ret;
+}
+
+/*
+ * DRBG Healthcheck function as required in SP800-90A
+ *
+ * return:
+ * 0 on success (all tests pass)
+ * >0 on error (return code indicate the number of failures)
+ */
+int
+drbg_healthcheck (void)
+{
+ int ret = 0;
+ ret += drbg_healthcheck_one (&drbg_test_nopr[0]);
+ ret += drbg_healthcheck_one (&drbg_test_nopr[1]);
+ ret += drbg_healthcheck_one (&drbg_test_nopr[2]);
+ ret += drbg_healthcheck_one (&drbg_test_pr[0]);
+ ret += drbg_healthcheck_one (&drbg_test_pr[1]);
+ ret += drbg_healthcheck_one (&drbg_test_pr[2]);
+ ret += drbg_healthcheck_sanity (&drbg_test_nopr[0]);
+ return ret;
+}
+
+/* Run the self-tests. */
+gcry_error_t
+_gcry_drbg_selftest (selftest_report_func_t report)
+{
+ gcry_err_code_t ec;
+ const char *errtxt = NULL;
+ drbg_lock ();
+ if (0 != drbg_healthcheck ())
+ errtxt = "RNG output does not match known value";
+ drbg_unlock ();
+ if (report && errtxt)
+ report ("random", 0, "KAT", errtxt);
+ ec = errtxt ? GPG_ERR_SELFTEST_FAILED : 0;
+ return gpg_error (ec);
+}
+
+/***************************************************************
+ * Cipher invocations requested by DRBG
+ ***************************************************************/
+
+static gpg_err_code_t
+drbg_gcry_hmac (struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *buf)
+{
+ gpg_error_t err;
+ gcry_md_hd_t hd;
+
+ if (key)
+ {
+ err = _gcry_md_open (&hd, drbg->core->backend_cipher, GCRY_MD_FLAG_HMAC);
+ if (err)
+ return err;
+ err = _gcry_md_setkey (hd, key, drbg_statelen (drbg));
+ if (err)
+ return err;
+ }
+ else
+ {
+ err = _gcry_md_open (&hd, drbg->core->backend_cipher, 0);
+ if (err)
+ return err;
+ }
+ for (; NULL != buf; buf = buf->next)
+ _gcry_md_write (hd, buf->buf, buf->len);
+ _gcry_md_final (hd);
+ memcpy (outval, _gcry_md_read (hd, drbg->core->backend_cipher),
+ drbg_blocklen (drbg));
+ _gcry_md_close (hd);
+ return 0;
+}
+
+static gpg_err_code_t
+drbg_gcry_sym (struct drbg_state *drbg, const unsigned char *key,
+ unsigned char *outval, const struct drbg_string *buf)
+{
+ gpg_error_t err;
+ gcry_cipher_hd_t hd;
+
+ err =
+ _gcry_cipher_open (&hd, drbg->core->backend_cipher, GCRY_CIPHER_MODE_ECB,
+ 0);
+ if (err)
+ return err;
+ if (drbg_blocklen (drbg) !=
+ _gcry_cipher_get_algo_blklen (drbg->core->backend_cipher))
+ return -GPG_ERR_NO_ERROR;
+ if (drbg_blocklen (drbg) < buf->len)
+ return -GPG_ERR_NO_ERROR;
+ err = _gcry_cipher_setkey (hd, key, drbg_keylen (drbg));
+ if (err)
+ return err;
+ /* in is only component */
+ _gcry_cipher_encrypt (hd, outval, drbg_blocklen (drbg), buf->buf, buf->len);
+ _gcry_cipher_close (hd);
+ return 0;
+}
--
1.9.3
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