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- /* LibTomCrypt, modular cryptographic library -- Tom St Denis
- *
- * LibTomCrypt is a library that provides various cryptographic
- * algorithms in a highly modular and flexible manner.
- *
- * The library is free for all purposes without any express
- * guarantee it works.
- */
- #include "tomcrypt.h"
-
- /**
- @file no_prng.c
- NO PRNG, Steffen Jaeckel
- */
-
- #ifdef LTC_PKCS_1
-
- typedef struct
- {
- struct ltc_prng_descriptor desc;
- char name[64];
- unsigned char entropy[1024];
- unsigned long len;
- unsigned long offset;
- } no_prng_desc_t;
-
- /**
- Start the PRNG
- @param prng [out] The PRNG state to initialize
- @return CRYPT_OK if successful
- */
- int no_prng_start(prng_state *prng)
- {
- no_prng_desc_t *no_prng = (no_prng_desc_t*) prng;
- LTC_ARGCHK(no_prng != NULL);
- LTC_ARGCHK(no_prng->name == (char*)no_prng + offsetof(no_prng_desc_t, name));
- no_prng->len = 0;
- no_prng->offset = 0;
-
- return CRYPT_OK;
- }
-
- /**
- Add entropy to the PRNG state
- @param in The data to add
- @param inlen Length of the data to add
- @param prng PRNG state to update
- @return CRYPT_OK if successful
- */
- int no_prng_add_entropy(const unsigned char *in, unsigned long inlen, prng_state *prng)
- {
- no_prng_desc_t *no_prng = (no_prng_desc_t*) prng;
- LTC_ARGCHK(no_prng != NULL);
- LTC_ARGCHK(no_prng->name == (char*)no_prng + offsetof(no_prng_desc_t, name));
- LTC_ARGCHK(in != NULL);
- LTC_ARGCHK(inlen <= sizeof(no_prng->entropy));
-
- no_prng->len = MIN(inlen, sizeof(no_prng->entropy));
- memcpy(no_prng->entropy, in, no_prng->len);
- no_prng->offset = 0;
-
- return CRYPT_OK;
-
- }
-
- /**
- Make the PRNG ready to read from
- @param prng The PRNG to make active
- @return CRYPT_OK if successful
- */
- int no_prng_ready(prng_state *prng)
- {
- LTC_ARGCHK(prng != NULL);
-
- return CRYPT_OK;
- }
-
- /**
- Read from the PRNG
- @param out Destination
- @param outlen Length of output
- @param prng The active PRNG to read from
- @return Number of octets read
- */
- unsigned long no_prng_read(unsigned char *out, unsigned long outlen, prng_state *prng)
- {
- no_prng_desc_t *no_prng = (no_prng_desc_t*) prng;
- LTC_ARGCHK(no_prng != NULL);
- LTC_ARGCHK(no_prng->name == (char*)no_prng + offsetof(no_prng_desc_t, name));
- LTC_ARGCHK(out != NULL);
-
- outlen = MIN(outlen, no_prng->len - no_prng->offset);
- memcpy(out, &no_prng->entropy[no_prng->offset], outlen);
- no_prng->offset += outlen;
-
- return outlen;
- }
-
- /**
- Terminate the PRNG
- @param prng The PRNG to terminate
- @return CRYPT_OK if successful
- */
- int no_prng_done(prng_state *prng)
- {
- LTC_UNUSED_PARAM(prng);
- return CRYPT_OK;
- }
-
- /**
- Export the PRNG state
- @param out [out] Destination
- @param outlen [in/out] Max size and resulting size of the state
- @param prng The PRNG to export
- @return CRYPT_OK if successful
- */
- int no_prng_export(unsigned char *out, unsigned long *outlen, prng_state *prng)
- {
- LTC_UNUSED_PARAM(out);
- LTC_UNUSED_PARAM(outlen);
- LTC_UNUSED_PARAM(prng);
- return CRYPT_OK;
- }
-
- /**
- Import a PRNG state
- @param in The PRNG state
- @param inlen Size of the state
- @param prng The PRNG to import
- @return CRYPT_OK if successful
- */
- int no_prng_import(const unsigned char *in, unsigned long inlen, prng_state *prng)
- {
- LTC_UNUSED_PARAM(in);
- LTC_UNUSED_PARAM(inlen);
- LTC_UNUSED_PARAM(prng);
- return CRYPT_OK;
- }
-
- /**
- PRNG self-test
- @return CRYPT_OK if successful, CRYPT_NOP if self-testing has been disabled
- */
- int no_prng_test(void)
- {
- return CRYPT_OK;
- }
-
- static const struct ltc_prng_descriptor no_prng_desc =
- {
- NULL, 0,
- &no_prng_start,
- &no_prng_add_entropy,
- &no_prng_ready,
- &no_prng_read,
- &no_prng_done,
- &no_prng_export,
- &no_prng_import,
- &no_prng_test
- };
-
- struct ltc_prng_descriptor* no_prng_desc_get(void)
- {
- no_prng_desc_t* no_prng = XMALLOC(sizeof(*no_prng));
- LTC_ARGCHK(no_prng != NULL);
- XMEMCPY(&no_prng->desc, &no_prng_desc, sizeof(no_prng_desc));
- LTC_ARGCHK(snprintf(no_prng->name, sizeof(no_prng->name), "no_prng@%p", no_prng) < (int)sizeof(no_prng->name));
- no_prng->desc.name = no_prng->name;
- return &no_prng->desc;
- }
-
- void no_prng_desc_free(struct ltc_prng_descriptor* prng)
- {
- no_prng_desc_t *no_prng = (no_prng_desc_t*) prng;
- LTC_ARGCHK(no_prng != NULL);
- LTC_ARGCHK(no_prng->name == (char*)no_prng + offsetof(no_prng_desc_t, name));
- XFREE(no_prng);
- }
-
- #endif
-
-
- /* ref: $Format:%D$ */
- /* git commit: $Format:%H$ */
- /* commit time: $Format:%ai$ */
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