diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/libstrongswan/crypto/rsa/rsa_public_key.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/src/libstrongswan/crypto/rsa/rsa_public_key.c b/src/libstrongswan/crypto/rsa/rsa_public_key.c index 2105d8ffe..16ac3bbbd 100644 --- a/src/libstrongswan/crypto/rsa/rsa_public_key.c +++ b/src/libstrongswan/crypto/rsa/rsa_public_key.c @@ -34,6 +34,7 @@ #include "rsa_public_key.h" #include <debug.h> +#include <utils/randomizer.h> #include <crypto/hashers/hasher.h> #include <asn1/asn1.h> #include <asn1/pem.h> @@ -137,6 +138,55 @@ static chunk_t rsaep(const private_rsa_public_key_t *this, chunk_t data) } /** + * Implementation of rsa_public_key_t.eme_pkcs1_encrypt. + */ +static status_t pkcs1_encrypt(private_rsa_public_key_t *this, + chunk_t in, chunk_t *out) +{ + chunk_t em; + u_char *pos; + int padding = this->k - in.len - 3; + + if (padding < 8) + { + DBG1("rsa padding of %d bytes is too small", padding); + return FAILED; + } + em.len = this->k; + em.ptr = pos = malloc(em.len); + + /* add padding according to PKCS#1 7.2.1 1.+2. */ + *pos++ = 0x00; + *pos++ = 0x02; + + /* pad with pseudo random bytes unequal to zero */ + { + randomizer_t *randomizer = randomizer_create(); + + /* pad with pseudo random bytes unequal to zero */ + while (padding--) + { + randomizer->get_pseudo_random_bytes(randomizer, 1, pos); + while (!*pos) + { + randomizer->get_pseudo_random_bytes(randomizer, 1, pos); + } + pos++; + } + randomizer->destroy(randomizer); + } + + /* append the padding terminator */ + *pos++ = 0x00; + + /* now add the data */ + memcpy(pos, in.ptr, in.len); + *out = this->rsaep(this, em); + free(em.ptr); + return SUCCESS; +} + +/** * Implementation of rsa_public_key.verify_emsa_pkcs1_signature. */ static status_t verify_emsa_pkcs1_signature(const private_rsa_public_key_t *this, @@ -376,6 +426,7 @@ private_rsa_public_key_t *rsa_public_key_create_empty(void) private_rsa_public_key_t *this = malloc_thing(private_rsa_public_key_t); /* public functions */ + this->public.pkcs1_encrypt = (status_t (*) (rsa_public_key_t*,chunk_t,chunk_t*))pkcs1_encrypt; this->public.verify_emsa_pkcs1_signature = (status_t (*) (const rsa_public_key_t*,hash_algorithm_t,chunk_t,chunk_t))verify_emsa_pkcs1_signature; this->public.get_modulus = (mpz_t *(*) (const rsa_public_key_t*))get_modulus; this->public.get_keysize = (size_t (*) (const rsa_public_key_t*))get_keysize; |