PR: 1794

[openssl.git] / apps / s_client.c

diff --git a/apps/s_client.c b/apps/s_client.c
index 1621a0158a9a11f15fbc31eb023d64e4cb5ac2a7..5c9e1c56a82cf2e32166f8c9dbed98287ce754f3 100644 (file)
--- a/apps/s_client.c
+++ b/apps/s_client.c
@@ -403,18 +403,18 @@ typedef struct srp_arg_st
 
 #define SRP_NUMBER_ITERATIONS_FOR_PRIME 64
 
-static int SRP_Verify_N_and_g(const BIGNUM *N, const BIGNUM *g)
+static int srp_Verify_N_and_g(const BIGNUM *N, const BIGNUM *g)
        {
        BN_CTX *bn_ctx = BN_CTX_new();
        BIGNUM *p = BN_new();
        BIGNUM *r = BN_new();
        int ret =
                g != NULL && N != NULL && bn_ctx != NULL && BN_is_odd(N) &&
-               BN_is_prime_ex(N,SRP_NUMBER_ITERATIONS_FOR_PRIME,bn_ctx,NULL) &&
+               BN_is_prime_ex(N, SRP_NUMBER_ITERATIONS_FOR_PRIME, bn_ctx, NULL) &&
                p != NULL && BN_rshift1(p, N) &&
 
                /* p = (N-1)/2 */
-               BN_is_prime_ex(p,SRP_NUMBER_ITERATIONS_FOR_PRIME,bn_ctx,NULL) &&
+               BN_is_prime_ex(p, SRP_NUMBER_ITERATIONS_FOR_PRIME, bn_ctx, NULL) &&
                r != NULL &&
 
                /* verify g^((N-1)/2) == -1 (mod N) */
@@ -431,6 +431,21 @@ static int SRP_Verify_N_and_g(const BIGNUM *N, const BIGNUM *g)
        return ret;
        }
 
+/* This callback is used here for two purposes:
+   - extended debugging
+   - making some primality tests for unknown groups
+   The callback is only called for a non default group.
+
+   An application does not need the call back at all if
+   only the stanard groups are used.  In real life situations, 
+   client and server already share well known groups, 
+   thus there is no need to verify them. 
+   Furthermore, in case that a server actually proposes a group that
+   is not one of those defined in RFC 5054, it is more appropriate 
+   to add the group to a static list and then compare since 
+   primality tests are rather cpu consuming.
+*/
+
 static int MS_CALLBACK ssl_srp_verify_param_cb(SSL *s, void *arg)
        {
        SRP_ARG *srp_arg = (SRP_ARG *)arg;
@@ -453,11 +468,11 @@ static int MS_CALLBACK ssl_srp_verify_param_cb(SSL *s, void *arg)
                if (srp_arg->debug)
                        BIO_printf(bio_err, "SRP param N and g are not known params, going to check deeper.\n");
 
-/* The srp_moregroups must be used with caution, testing primes costs time. 
+/* The srp_moregroups is a real debugging feature.
    Implementors should rather add the value to the known ones.
    The minimal size has already been tested.
 */
-               if (BN_num_bits(g) <= BN_BITS && SRP_Verify_N_and_g(N,g))
+               if (BN_num_bits(g) <= BN_BITS && srp_Verify_N_and_g(N,g))
                        return 1;
                }       
        BIO_printf(bio_err, "SRP param N and g rejected.\n");
@@ -486,12 +501,6 @@ static char * MS_CALLBACK ssl_give_srp_client_pwd_cb(SSL *s, void *arg)
        return pass;
        }
 
-static char * MS_CALLBACK missing_srp_username_callback(SSL *s, void *arg)
-       {
-       SRP_ARG *srp_arg = (SRP_ARG *)arg;
-       return BUF_strdup(srp_arg->srplogin);
-       }
-
 #endif
        char *srtp_profiles = NULL;
 
@@ -1182,9 +1191,7 @@ bad:
 #ifndef OPENSSL_NO_SRP
         if (srp_arg.srplogin)
                {
-               if (srp_lateuser) 
-                       SSL_CTX_set_srp_missing_srp_username_callback(ctx,missing_srp_username_callback);
-               else if (!SSL_CTX_set_srp_username(ctx, srp_arg.srplogin))
+               if (!srp_lateuser && !SSL_CTX_set_srp_username(ctx, srp_arg.srplogin))
                        {
                        BIO_printf(bio_err,"Unable to set SRP username\n");
                        goto end;