+
+int DSA_sign(int type, const unsigned char *dgst, int dlen, unsigned char *sig,
+ unsigned int *siglen, DSA *dsa)
+ {
+ DSA_SIG *s;
+#ifdef OPENSSL_FIPS
+ if(FIPS_mode() && !(dsa->flags & DSA_FLAG_NON_FIPS_ALLOW))
+ {
+ DSAerr(DSA_F_DSA_SIGN, DSA_R_OPERATION_NOT_ALLOWED_IN_FIPS_MODE);
+ return 0;
+ }
+#endif
+ s=DSA_do_sign(dgst,dlen,dsa);
+ if (s == NULL)
+ {
+ *siglen=0;
+ return(0);
+ }
+ *siglen=i2d_DSA_SIG(s,&sig);
+ DSA_SIG_free(s);
+ return(1);
+ }
+
+int DSA_size(const DSA *r)
+ {
+ int ret,i;
+ ASN1_INTEGER bs;
+ unsigned char buf[4]; /* 4 bytes looks really small.
+ However, i2d_ASN1_INTEGER() will not look
+ beyond the first byte, as long as the second
+ parameter is NULL. */
+
+ i=BN_num_bits(r->q);
+ bs.length=(i+7)/8;
+ bs.data=buf;
+ bs.type=V_ASN1_INTEGER;
+ /* If the top bit is set the asn1 encoding is 1 larger. */
+ buf[0]=0xff;
+
+ i=i2d_ASN1_INTEGER(&bs,NULL);
+ i+=i; /* r and s */
+ ret=ASN1_object_size(1,i,V_ASN1_SEQUENCE);
+ return(ret);
+ }
+
+/* data has already been hashed (probably with SHA or SHA-1). */
+/* returns
+ * 1: correct signature
+ * 0: incorrect signature
+ * -1: error
+ */
+int DSA_verify(int type, const unsigned char *dgst, int dgst_len,
+ const unsigned char *sigbuf, int siglen, DSA *dsa)
+ {
+ DSA_SIG *s;
+ int ret=-1;
+#ifdef OPENSSL_FIPS
+ if(FIPS_mode() && !(dsa->flags & DSA_FLAG_NON_FIPS_ALLOW))
+ {
+ DSAerr(DSA_F_DSA_VERIFY, DSA_R_OPERATION_NOT_ALLOWED_IN_FIPS_MODE);
+ return 0;
+ }
+#endif
+
+ s = DSA_SIG_new();
+ if (s == NULL) return(ret);
+ if (d2i_DSA_SIG(&s,&sigbuf,siglen) == NULL) goto err;
+ ret=DSA_do_verify(dgst,dgst_len,s,dsa);
+err:
+ DSA_SIG_free(s);
+ return(ret);
+ }
+