diff options
Diffstat (limited to 'scd/app-openpgp.c')
| -rw-r--r-- | scd/app-openpgp.c | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/scd/app-openpgp.c b/scd/app-openpgp.c index 7bbec03ac..ab57d90e6 100644 --- a/scd/app-openpgp.c +++ b/scd/app-openpgp.c @@ -2061,6 +2061,9 @@ get_prompt_info (app_t app, int chvno, unsigned long sigcount, int remaining) return result; } +#define KDF_DATA_LENGTH_MIN 90 +#define KDF_DATA_LENGTH_MAX 110 + /* Compute hash if KDF-DO is available. CHVNO must be 0 for reset code, 1 or 2 for user pin and 3 for admin pin. */ @@ -2068,21 +2071,33 @@ static gpg_error_t pin2hash_if_kdf (app_t app, int chvno, char *pinvalue, int *r_pinlen) { gpg_error_t err = 0; - void *relptr; + void *relptr = NULL; unsigned char *buffer; size_t buflen; if (app->app_local->extcap.kdf_do && (relptr = get_one_do (app, 0x00F9, &buffer, &buflen, NULL)) - && buflen == 110 && (buffer[2] == 0x03)) + && buflen >= KDF_DATA_LENGTH_MIN && (buffer[2] == 0x03)) { - char *salt; + const char *salt; unsigned long s2k_count; char dek[32]; + int salt_index; - salt = &buffer[(chvno==3 ? 34 : (chvno==0 ? 24 : 14))]; s2k_count = (((unsigned int)buffer[8] << 24) | (buffer[9] << 16) | (buffer[10] << 8) | buffer[11]); + + if (buflen == KDF_DATA_LENGTH_MIN) + salt_index =14; + else if (buflen == KDF_DATA_LENGTH_MAX) + salt_index = (chvno==3 ? 34 : (chvno==0 ? 24 : 14)); + else + { + err = gpg_error (GPG_ERR_INV_DATA); + goto leave; + } + + salt = &buffer[salt_index]; err = gcry_kdf_derive (pinvalue, strlen (pinvalue), GCRY_KDF_ITERSALTED_S2K, DIGEST_ALGO_SHA256, salt, 8, @@ -2094,12 +2109,12 @@ pin2hash_if_kdf (app_t app, int chvno, char *pinvalue, int *r_pinlen) memcpy (pinvalue, dek, *r_pinlen); wipememory (dek, *r_pinlen); } - - xfree (relptr); - } + } else *r_pinlen = strlen (pinvalue); + leave: + xfree (relptr); return err; } |