diff options
| author | Janos Follath <janos.follath@arm.com> | 2023-12-27 10:33:00 +0000 |
|---|---|---|
| committer | Dave Rodgman <dave.rodgman@arm.com> | 2024-01-22 15:33:19 +0000 |
| commit | 47ee7708123347a925aac44709e53a13d1c486e8 (patch) | |
| tree | cef1e3f58717334c327671f2b57b56bc1084f0be | |
| parent | e6750b2a0bf750d35172bdef12c2dcfc28213207 (diff) | |
| download | mbedtls-47ee7708123347a925aac44709e53a13d1c486e8.tar.gz | |
RSA: remove unneeded temporaries
Signed-off-by: Janos Follath <janos.follath@arm.com>
| -rw-r--r-- | library/rsa.c | 21 |
1 files changed, 3 insertions, 18 deletions
diff --git a/library/rsa.c b/library/rsa.c index f57909b71..111af680f 100644 --- a/library/rsa.c +++ b/library/rsa.c @@ -1056,18 +1056,9 @@ int mbedtls_rsa_private(mbedtls_rsa_context *ctx, /* Temporaries holding the blinded exponents for * the mod p resp. mod q computation (if used). */ mbedtls_mpi DP_blind, DQ_blind; - - /* Pointers to actual exponents to be used - either the unblinded - * or the blinded ones, depending on the presence of a PRNG. */ - mbedtls_mpi *DP = &ctx->DP; - mbedtls_mpi *DQ = &ctx->DQ; #else /* Temporary holding the blinded exponent (if used). */ mbedtls_mpi D_blind; - - /* Pointer to actual exponent to be used - either the unblinded - * or the blinded one, depending on the presence of a PRNG. */ - mbedtls_mpi *D = &ctx->D; #endif /* MBEDTLS_RSA_NO_CRT */ /* Temporaries holding the initial input and the double @@ -1143,8 +1134,6 @@ int mbedtls_rsa_private(mbedtls_rsa_context *ctx, MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&D_blind, &P1, &Q1)); MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&D_blind, &D_blind, &R)); MBEDTLS_MPI_CHK(mbedtls_mpi_add_mpi(&D_blind, &D_blind, &ctx->D)); - - D = &D_blind; #else /* * DP_blind = ( P - 1 ) * R + DP @@ -1155,8 +1144,6 @@ int mbedtls_rsa_private(mbedtls_rsa_context *ctx, MBEDTLS_MPI_CHK(mbedtls_mpi_add_mpi(&DP_blind, &DP_blind, &ctx->DP)); - DP = &DP_blind; - /* * DQ_blind = ( Q - 1 ) * R + DQ */ @@ -1165,12 +1152,10 @@ int mbedtls_rsa_private(mbedtls_rsa_context *ctx, MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&DQ_blind, &Q1, &R)); MBEDTLS_MPI_CHK(mbedtls_mpi_add_mpi(&DQ_blind, &DQ_blind, &ctx->DQ)); - - DQ = &DQ_blind; #endif /* MBEDTLS_RSA_NO_CRT */ #if defined(MBEDTLS_RSA_NO_CRT) - MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&T, &T, D, &ctx->N, &ctx->RN)); + MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&T, &T, &D_blind, &ctx->N, &ctx->RN)); #else /* * Faster decryption using the CRT @@ -1179,8 +1164,8 @@ int mbedtls_rsa_private(mbedtls_rsa_context *ctx, * TQ = input ^ dQ mod Q */ - MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&TP, &T, DP, &ctx->P, &ctx->RP)); - MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&TQ, &T, DQ, &ctx->Q, &ctx->RQ)); + MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&TP, &T, &DP_blind, &ctx->P, &ctx->RP)); + MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&TQ, &T, &DQ_blind, &ctx->Q, &ctx->RQ)); /* * T = (TP - TQ) * (Q^-1 mod P) mod P |