Squashed 'lib/mbedtls/external/mbedtls/' content from commit 2ca6c285a0dd

git-subtree-dir: lib/mbedtls/external/mbedtls
git-subtree-split: 2ca6c285a0dd3f33982dd57299012dacab1ff206
diff --git a/programs/pkey/rsa_decrypt.c b/programs/pkey/rsa_decrypt.c
new file mode 100644
index 0000000..a84af50
--- /dev/null
+++ b/programs/pkey/rsa_decrypt.c
@@ -0,0 +1,172 @@
+/*
+ *  RSA simple decryption program
+ *
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+#include "mbedtls/build_info.h"
+
+#include "mbedtls/platform.h"
+
+#if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_RSA_C) && \
+    defined(MBEDTLS_FS_IO) && defined(MBEDTLS_ENTROPY_C) && \
+    defined(MBEDTLS_CTR_DRBG_C)
+#include "mbedtls/rsa.h"
+#include "mbedtls/entropy.h"
+#include "mbedtls/ctr_drbg.h"
+
+#include <string.h>
+
+#endif
+
+#if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_RSA_C) ||  \
+    !defined(MBEDTLS_FS_IO) || !defined(MBEDTLS_ENTROPY_C) || \
+    !defined(MBEDTLS_CTR_DRBG_C)
+int main(void)
+{
+    mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_RSA_C and/or "
+                   "MBEDTLS_FS_IO and/or MBEDTLS_ENTROPY_C and/or "
+                   "MBEDTLS_CTR_DRBG_C not defined.\n");
+    mbedtls_exit(0);
+}
+#else
+
+
+int main(int argc, char *argv[])
+{
+    FILE *f;
+    int ret = 1;
+    int exit_code = MBEDTLS_EXIT_FAILURE;
+    unsigned c;
+    size_t i;
+    mbedtls_rsa_context rsa;
+    mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
+    mbedtls_entropy_context entropy;
+    mbedtls_ctr_drbg_context ctr_drbg;
+    unsigned char result[1024];
+    unsigned char buf[512];
+    const char *pers = "rsa_decrypt";
+    ((void) argv);
+
+    memset(result, 0, sizeof(result));
+
+    if (argc != 1) {
+        mbedtls_printf("usage: rsa_decrypt\n");
+
+#if defined(_WIN32)
+        mbedtls_printf("\n");
+#endif
+
+        mbedtls_exit(exit_code);
+    }
+
+    mbedtls_printf("\n  . Seeding the random number generator...");
+    fflush(stdout);
+
+    mbedtls_rsa_init(&rsa);
+    mbedtls_ctr_drbg_init(&ctr_drbg);
+    mbedtls_entropy_init(&entropy);
+    mbedtls_mpi_init(&N); mbedtls_mpi_init(&P); mbedtls_mpi_init(&Q);
+    mbedtls_mpi_init(&D); mbedtls_mpi_init(&E); mbedtls_mpi_init(&DP);
+    mbedtls_mpi_init(&DQ); mbedtls_mpi_init(&QP);
+
+    ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func,
+                                &entropy, (const unsigned char *) pers,
+                                strlen(pers));
+    if (ret != 0) {
+        mbedtls_printf(" failed\n  ! mbedtls_ctr_drbg_seed returned %d\n",
+                       ret);
+        goto exit;
+    }
+
+    mbedtls_printf("\n  . Reading private key from rsa_priv.txt");
+    fflush(stdout);
+
+    if ((f = fopen("rsa_priv.txt", "rb")) == NULL) {
+        mbedtls_printf(" failed\n  ! Could not open rsa_priv.txt\n" \
+                       "  ! Please run rsa_genkey first\n\n");
+        goto exit;
+    }
+
+    if ((ret = mbedtls_mpi_read_file(&N, 16, f))  != 0 ||
+        (ret = mbedtls_mpi_read_file(&E, 16, f))  != 0 ||
+        (ret = mbedtls_mpi_read_file(&D, 16, f))  != 0 ||
+        (ret = mbedtls_mpi_read_file(&P, 16, f))  != 0 ||
+        (ret = mbedtls_mpi_read_file(&Q, 16, f))  != 0 ||
+        (ret = mbedtls_mpi_read_file(&DP, 16, f)) != 0 ||
+        (ret = mbedtls_mpi_read_file(&DQ, 16, f)) != 0 ||
+        (ret = mbedtls_mpi_read_file(&QP, 16, f)) != 0) {
+        mbedtls_printf(" failed\n  ! mbedtls_mpi_read_file returned %d\n\n",
+                       ret);
+        fclose(f);
+        goto exit;
+    }
+    fclose(f);
+
+    if ((ret = mbedtls_rsa_import(&rsa, &N, &P, &Q, &D, &E)) != 0) {
+        mbedtls_printf(" failed\n  ! mbedtls_rsa_import returned %d\n\n",
+                       ret);
+        goto exit;
+    }
+
+    if ((ret = mbedtls_rsa_complete(&rsa)) != 0) {
+        mbedtls_printf(" failed\n  ! mbedtls_rsa_complete returned %d\n\n",
+                       ret);
+        goto exit;
+    }
+
+    /*
+     * Extract the RSA encrypted value from the text file
+     */
+    if ((f = fopen("result-enc.txt", "rb")) == NULL) {
+        mbedtls_printf("\n  ! Could not open %s\n\n", "result-enc.txt");
+        goto exit;
+    }
+
+    i = 0;
+
+    while (fscanf(f, "%02X", (unsigned int *) &c) > 0 &&
+           i < (int) sizeof(buf)) {
+        buf[i++] = (unsigned char) c;
+    }
+
+    fclose(f);
+
+    if (i != mbedtls_rsa_get_len(&rsa)) {
+        mbedtls_printf("\n  ! Invalid RSA signature format\n\n");
+        goto exit;
+    }
+
+    /*
+     * Decrypt the encrypted RSA data and print the result.
+     */
+    mbedtls_printf("\n  . Decrypting the encrypted data");
+    fflush(stdout);
+
+    ret = mbedtls_rsa_pkcs1_decrypt(&rsa, mbedtls_ctr_drbg_random,
+                                    &ctr_drbg, &i,
+                                    buf, result, 1024);
+    if (ret != 0) {
+        mbedtls_printf(" failed\n  ! mbedtls_rsa_pkcs1_decrypt returned %d\n\n",
+                       ret);
+        goto exit;
+    }
+
+    mbedtls_printf("\n  . OK\n\n");
+
+    mbedtls_printf("The decrypted result is: '%s'\n\n", result);
+
+    exit_code = MBEDTLS_EXIT_SUCCESS;
+
+exit:
+    mbedtls_ctr_drbg_free(&ctr_drbg);
+    mbedtls_entropy_free(&entropy);
+    mbedtls_rsa_free(&rsa);
+    mbedtls_mpi_free(&N); mbedtls_mpi_free(&P); mbedtls_mpi_free(&Q);
+    mbedtls_mpi_free(&D); mbedtls_mpi_free(&E); mbedtls_mpi_free(&DP);
+    mbedtls_mpi_free(&DQ); mbedtls_mpi_free(&QP);
+
+    mbedtls_exit(exit_code);
+}
+#endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_FS_IO */