diff options
Diffstat (limited to 'g10/pkglue.c')
| -rw-r--r-- | g10/pkglue.c | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/g10/pkglue.c b/g10/pkglue.c index 747159759..e89f3647e 100644 --- a/g10/pkglue.c +++ b/g10/pkglue.c @@ -47,6 +47,41 @@ get_mpi_from_sexp (gcry_sexp_t sexp, const char *item, int mpifmt) } +gcry_mpi_t +get_sos_from_sexp (gcry_sexp_t sexp, const char *item) +{ + gcry_sexp_t list; + size_t buflen; + void *p0; + gcry_mpi_t sos; + unsigned int nbits; + unsigned char *p; + + list = gcry_sexp_find_token (sexp, item, 0); + log_assert (list); + p0 = gcry_sexp_nth_buffer (list, 1, &buflen); + log_assert (p0); + nbits = buflen*8; + p = p0; + + if (nbits >= 8 && !(*p & 0x80)) + if (--nbits >= 7 && !(*p & 0x40)) + if (--nbits >= 6 && !(*p & 0x20)) + if (--nbits >= 5 && !(*p & 0x10)) + if (--nbits >= 4 && !(*p & 0x08)) + if (--nbits >= 3 && !(*p & 0x04)) + if (--nbits >= 2 && !(*p & 0x02)) + if (--nbits >= 1 && !(*p & 0x01)) + --nbits; + + sos = gcry_mpi_set_opaque (NULL, p0, nbits); + log_assert (sos); + gcry_sexp_release (list); + gcry_mpi_set_flag (sos, GCRYMPI_FLAG_USER2); + return sos; +} + + static byte * get_data_from_sexp (gcry_sexp_t sexp, const char *item, size_t *r_size) { @@ -360,7 +395,7 @@ pk_encrypt (pubkey_algo_t algo, gcry_mpi_t *resarr, gcry_mpi_t data, /* Get the shared point and the ephemeral public key. */ shared = get_data_from_sexp (s_ciph, "s", &nshared); - public = get_mpi_from_sexp (s_ciph, "e", GCRYMPI_FMT_OPAQUE); + public = get_sos_from_sexp (s_ciph, "e"); if (DBG_CRYPTO) { log_debug ("ECDH ephemeral key:"); |