/* * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the Apache License 2.0 (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html */ /* * DSA low level APIs are deprecated for public use, but still ok for * internal use. */ #include "internal/deprecated.h" #include <openssl/bn.h> #include "internal/cryptlib.h" #include "dsa_local.h" #include "crypto/asn1_dsa.h" #include "crypto/dsa.h" DSA_SIG *DSA_do_sign(const unsigned char *dgst, int dlen, DSA *dsa) { return dsa->meth->dsa_do_sign(dgst, dlen, dsa); } #ifndef OPENSSL_NO_DEPRECATED_3_0 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) ERR_raise(ERR_LIB_DSA, 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 (sig->r == NULL || sig->s == NULL || ossl_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 (!ossl_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 = -1; DSA_SIG sig; if (dsa->params.q != NULL) { sig.r = sig.s = dsa->params.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 ossl_dsa_sign_int(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 (dsa->libctx == NULL || dsa->meth != DSA_get_default_method()) s = DSA_do_sign(dgst, dlen, dsa); else s = ossl_dsa_do_sign_int(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 ossl_dsa_sign_int(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; }