Add dsa signature alg to fips provider

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10615)

1 files changed, 178 insertions, 1 deletions

diff --git a/crypto/dsa/dsa_sign.c b/crypto/dsa/dsa_sign.c
index 99ef0043eb..d09aaea6db 100644
--- a/crypto/dsa/dsa_sign.c
+++ b/crypto/dsa/dsa_sign.c
@@ -7,9 +7,11 @@
  * https://www.openssl.org/source/license.html
  */
 
+#include <openssl/bn.h>
 #include "internal/cryptlib.h"
 #include "dsa_local.h"
-#include <openssl/bn.h>
+#include "crypto/asn1_dsa.h"
+#include "crypto/dsa.h"
 
 DSA_SIG *DSA_do_sign(const unsigned char *dgst, int dlen, DSA *dsa)
 {
@@ -22,3 +24,178 @@ int DSA_sign_setup(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp)
     return dsa->meth->dsa_sign_setup(dsa, ctx_in, kinvp, rp);
 }
 #endif
+
+DSA_SIG *DSA_SIG_new(void)
+{
+    DSA_SIG *sig = OPENSSL_zalloc(sizeof(*sig));
+    if (sig == NULL)
+        DSAerr(DSA_F_DSA_SIG_NEW, ERR_R_MALLOC_FAILURE);
+    return sig;
+}
+
+void DSA_SIG_free(DSA_SIG *sig)
+{
+    if (sig == NULL)
+        return;
+    BN_clear_free(sig->r);
+    BN_clear_free(sig->s);
+    OPENSSL_free(sig);
+}
+
+DSA_SIG *d2i_DSA_SIG(DSA_SIG **psig, const unsigned char **ppin, long len)
+{
+    DSA_SIG *sig;
+
+    if (len < 0)
+        return NULL;
+    if (psig != NULL && *psig != NULL) {
+        sig = *psig;
+    } else {
+        sig = DSA_SIG_new();
+        if (sig == NULL)
+            return NULL;
+    }
+    if (sig->r == NULL)
+        sig->r = BN_new();
+    if (sig->s == NULL)
+        sig->s = BN_new();
+    if (decode_der_dsa_sig(sig->r, sig->s, ppin, (size_t)len) == 0) {
+        if (psig == NULL || *psig == NULL)
+            DSA_SIG_free(sig);
+        return NULL;
+    }
+    if (psig != NULL && *psig == NULL)
+        *psig = sig;
+    return sig;
+}
+
+int i2d_DSA_SIG(const DSA_SIG *sig, unsigned char **ppout)
+{
+    BUF_MEM *buf = NULL;
+    size_t encoded_len;
+    WPACKET pkt;
+
+    if (ppout == NULL) {
+        if (!WPACKET_init_null(&pkt, 0))
+            return -1;
+    } else if (*ppout == NULL) {
+        if ((buf = BUF_MEM_new()) == NULL
+                || !WPACKET_init_len(&pkt, buf, 0)) {
+            BUF_MEM_free(buf);
+            return -1;
+        }
+    } else {
+        if (!WPACKET_init_static_len(&pkt, *ppout, SIZE_MAX, 0))
+            return -1;
+    }
+
+    if (!encode_der_dsa_sig(&pkt, sig->r, sig->s)
+            || !WPACKET_get_total_written(&pkt, &encoded_len)
+            || !WPACKET_finish(&pkt)) {
+        BUF_MEM_free(buf);
+        WPACKET_cleanup(&pkt);
+        return -1;
+    }
+
+    if (ppout != NULL) {
+        if (*ppout == NULL) {
+            *ppout = (unsigned char *)buf->data;
+            buf->data = NULL;
+            BUF_MEM_free(buf);
+        } else {
+            *ppout += encoded_len;
+        }
+    }
+
+    return (int)encoded_len;
+}
+
+int DSA_size(const DSA *dsa)
+{
+    int ret;
+    DSA_SIG sig;
+
+    sig.r = sig.s = dsa->q;
+    ret = i2d_DSA_SIG(&sig, NULL);
+
+    if (ret < 0)
+        ret = 0;
+    return ret;
+}
+
+void DSA_SIG_get0(const DSA_SIG *sig, const BIGNUM **pr, const BIGNUM **ps)
+{
+    if (pr != NULL)
+        *pr = sig->r;
+    if (ps != NULL)
+        *ps = sig->s;
+}
+
+int DSA_SIG_set0(DSA_SIG *sig, BIGNUM *r, BIGNUM *s)
+{
+    if (r == NULL || s == NULL)
+        return 0;
+    BN_clear_free(sig->r);
+    BN_clear_free(sig->s);
+    sig->r = r;
+    sig->s = s;
+    return 1;
+}
+
+int dsa_sign_int(OPENSSL_CTX *libctx, int type, const unsigned char *dgst,
+                 int dlen, unsigned char *sig, unsigned int *siglen, DSA *dsa)
+{
+    DSA_SIG *s;
+
+    /* legacy case uses the method table */
+    if (libctx == NULL || dsa->meth != DSA_get_default_method())
+        s = DSA_do_sign(dgst, dlen, dsa);
+    else
+        s = dsa_do_sign_int(libctx, dgst, dlen, dsa);
+    if (s == NULL) {
+        *siglen = 0;
+        return 0;
+    }
+    *siglen = i2d_DSA_SIG(s, &sig);
+    DSA_SIG_free(s);
+    return 1;
+}
+
+int DSA_sign(int type, const unsigned char *dgst, int dlen,
+             unsigned char *sig, unsigned int *siglen, DSA *dsa)
+{
+    return dsa_sign_int(NULL, type, dgst, dlen, sig, siglen, dsa);
+}
+
+/* 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;
+    const unsigned char *p = sigbuf;
+    unsigned char *der = NULL;
+    int derlen = -1;
+    int ret = -1;
+
+    s = DSA_SIG_new();
+    if (s == NULL)
+        return ret;
+    if (d2i_DSA_SIG(&s, &p, siglen) == NULL)
+        goto err;
+    /* Ensure signature uses DER and doesn't have trailing garbage */
+    derlen = i2d_DSA_SIG(s, &der);
+    if (derlen != siglen || memcmp(sigbuf, der, derlen))
+        goto err;
+    ret = DSA_do_verify(dgst, dgst_len, s, dsa);
+ err:
+    OPENSSL_clear_free(der, derlen);
+    DSA_SIG_free(s);
+    return ret;
+}
+