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

git-subtree-dir: lib/mbedtls/external/mbedtls
git-subtree-split: 2ca6c285a0dd3f33982dd57299012dacab1ff206

1 files changed, 633 insertions, 0 deletions

diff --git a/library/hmac_drbg.c b/library/hmac_drbg.c
new file mode 100644
index 00000000000..90174d5d17d
--- /dev/null
+++ b/library/hmac_drbg.c
@@ -0,0 +1,633 @@
+/*
+ *  HMAC_DRBG implementation (NIST SP 800-90)
+ *
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+/*
+ *  The NIST SP 800-90A DRBGs are described in the following publication.
+ *  http://csrc.nist.gov/publications/nistpubs/800-90A/SP800-90A.pdf
+ *  References below are based on rev. 1 (January 2012).
+ */
+
+#include "common.h"
+
+#if defined(MBEDTLS_HMAC_DRBG_C)
+
+#include "mbedtls/hmac_drbg.h"
+#include "mbedtls/platform_util.h"
+#include "mbedtls/error.h"
+
+#include <string.h>
+
+#if defined(MBEDTLS_FS_IO)
+#include <stdio.h>
+#endif
+
+#include "mbedtls/platform.h"
+
+/*
+ * HMAC_DRBG context initialization
+ */
+void mbedtls_hmac_drbg_init(mbedtls_hmac_drbg_context *ctx)
+{
+    memset(ctx, 0, sizeof(mbedtls_hmac_drbg_context));
+
+    ctx->reseed_interval = MBEDTLS_HMAC_DRBG_RESEED_INTERVAL;
+}
+
+/*
+ * HMAC_DRBG update, using optional additional data (10.1.2.2)
+ */
+int mbedtls_hmac_drbg_update(mbedtls_hmac_drbg_context *ctx,
+                             const unsigned char *additional,
+                             size_t add_len)
+{
+    size_t md_len = mbedtls_md_get_size(ctx->md_ctx.md_info);
+    unsigned char rounds = (additional != NULL && add_len != 0) ? 2 : 1;
+    unsigned char sep[1];
+    unsigned char K[MBEDTLS_MD_MAX_SIZE];
+    int ret = MBEDTLS_ERR_MD_BAD_INPUT_DATA;
+
+    for (sep[0] = 0; sep[0] < rounds; sep[0]++) {
+        /* Step 1 or 4 */
+        if ((ret = mbedtls_md_hmac_reset(&ctx->md_ctx)) != 0) {
+            goto exit;
+        }
+        if ((ret = mbedtls_md_hmac_update(&ctx->md_ctx,
+                                          ctx->V, md_len)) != 0) {
+            goto exit;
+        }
+        if ((ret = mbedtls_md_hmac_update(&ctx->md_ctx,
+                                          sep, 1)) != 0) {
+            goto exit;
+        }
+        if (rounds == 2) {
+            if ((ret = mbedtls_md_hmac_update(&ctx->md_ctx,
+                                              additional, add_len)) != 0) {
+                goto exit;
+            }
+        }
+        if ((ret = mbedtls_md_hmac_finish(&ctx->md_ctx, K)) != 0) {
+            goto exit;
+        }
+
+        /* Step 2 or 5 */
+        if ((ret = mbedtls_md_hmac_starts(&ctx->md_ctx, K, md_len)) != 0) {
+            goto exit;
+        }
+        if ((ret = mbedtls_md_hmac_update(&ctx->md_ctx,
+                                          ctx->V, md_len)) != 0) {
+            goto exit;
+        }
+        if ((ret = mbedtls_md_hmac_finish(&ctx->md_ctx, ctx->V)) != 0) {
+            goto exit;
+        }
+    }
+
+exit:
+    mbedtls_platform_zeroize(K, sizeof(K));
+    return ret;
+}
+
+/*
+ * Simplified HMAC_DRBG initialisation (for use with deterministic ECDSA)
+ */
+int mbedtls_hmac_drbg_seed_buf(mbedtls_hmac_drbg_context *ctx,
+                               const mbedtls_md_info_t *md_info,
+                               const unsigned char *data, size_t data_len)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
+    if ((ret = mbedtls_md_setup(&ctx->md_ctx, md_info, 1)) != 0) {
+        return ret;
+    }
+
+#if defined(MBEDTLS_THREADING_C)
+    mbedtls_mutex_init(&ctx->mutex);
+#endif
+
+    /*
+     * Set initial working state.
+     * Use the V memory location, which is currently all 0, to initialize the
+     * MD context with an all-zero key. Then set V to its initial value.
+     */
+    if ((ret = mbedtls_md_hmac_starts(&ctx->md_ctx, ctx->V,
+                                      mbedtls_md_get_size(md_info))) != 0) {
+        return ret;
+    }
+    memset(ctx->V, 0x01, mbedtls_md_get_size(md_info));
+
+    if ((ret = mbedtls_hmac_drbg_update(ctx, data, data_len)) != 0) {
+        return ret;
+    }
+
+    return 0;
+}
+
+/*
+ * Internal function used both for seeding and reseeding the DRBG.
+ * Comments starting with arabic numbers refer to section 10.1.2.4
+ * of SP800-90A, while roman numbers refer to section 9.2.
+ */
+static int hmac_drbg_reseed_core(mbedtls_hmac_drbg_context *ctx,
+                                 const unsigned char *additional, size_t len,
+                                 int use_nonce)
+{
+    unsigned char seed[MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT];
+    size_t seedlen = 0;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
+    {
+        size_t total_entropy_len;
+
+        if (use_nonce == 0) {
+            total_entropy_len = ctx->entropy_len;
+        } else {
+            total_entropy_len = ctx->entropy_len * 3 / 2;
+        }
+
+        /* III. Check input length */
+        if (len > MBEDTLS_HMAC_DRBG_MAX_INPUT ||
+            total_entropy_len + len > MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT) {
+            return MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG;
+        }
+    }
+
+    memset(seed, 0, MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT);
+
+    /* IV. Gather entropy_len bytes of entropy for the seed */
+    if ((ret = ctx->f_entropy(ctx->p_entropy,
+                              seed, ctx->entropy_len)) != 0) {
+        return MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED;
+    }
+    seedlen += ctx->entropy_len;
+
+    /* For initial seeding, allow adding of nonce generated
+     * from the entropy source. See Sect 8.6.7 in SP800-90A. */
+    if (use_nonce) {
+        /* Note: We don't merge the two calls to f_entropy() in order
+         *       to avoid requesting too much entropy from f_entropy()
+         *       at once. Specifically, if the underlying digest is not
+         *       SHA-1, 3 / 2 * entropy_len is at least 36 Bytes, which
+         *       is larger than the maximum of 32 Bytes that our own
+         *       entropy source implementation can emit in a single
+         *       call in configurations disabling SHA-512. */
+        if ((ret = ctx->f_entropy(ctx->p_entropy,
+                                  seed + seedlen,
+                                  ctx->entropy_len / 2)) != 0) {
+            return MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED;
+        }
+
+        seedlen += ctx->entropy_len / 2;
+    }
+
+
+    /* 1. Concatenate entropy and additional data if any */
+    if (additional != NULL && len != 0) {
+        memcpy(seed + seedlen, additional, len);
+        seedlen += len;
+    }
+
+    /* 2. Update state */
+    if ((ret = mbedtls_hmac_drbg_update(ctx, seed, seedlen)) != 0) {
+        goto exit;
+    }
+
+    /* 3. Reset reseed_counter */
+    ctx->reseed_counter = 1;
+
+exit:
+    /* 4. Done */
+    mbedtls_platform_zeroize(seed, seedlen);
+    return ret;
+}
+
+/*
+ * HMAC_DRBG reseeding: 10.1.2.4 + 9.2
+ */
+int mbedtls_hmac_drbg_reseed(mbedtls_hmac_drbg_context *ctx,
+                             const unsigned char *additional, size_t len)
+{
+    return hmac_drbg_reseed_core(ctx, additional, len, 0);
+}
+
+/*
+ * HMAC_DRBG initialisation (10.1.2.3 + 9.1)
+ *
+ * The nonce is not passed as a separate parameter but extracted
+ * from the entropy source as suggested in 8.6.7.
+ */
+int mbedtls_hmac_drbg_seed(mbedtls_hmac_drbg_context *ctx,
+                           const mbedtls_md_info_t *md_info,
+                           int (*f_entropy)(void *, unsigned char *, size_t),
+                           void *p_entropy,
+                           const unsigned char *custom,
+                           size_t len)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t md_size;
+
+    if ((ret = mbedtls_md_setup(&ctx->md_ctx, md_info, 1)) != 0) {
+        return ret;
+    }
+
+    /* The mutex is initialized iff the md context is set up. */
+#if defined(MBEDTLS_THREADING_C)
+    mbedtls_mutex_init(&ctx->mutex);
+#endif
+
+    md_size = mbedtls_md_get_size(md_info);
+
+    /*
+     * Set initial working state.
+     * Use the V memory location, which is currently all 0, to initialize the
+     * MD context with an all-zero key. Then set V to its initial value.
+     */
+    if ((ret = mbedtls_md_hmac_starts(&ctx->md_ctx, ctx->V, md_size)) != 0) {
+        return ret;
+    }
+    memset(ctx->V, 0x01, md_size);
+
+    ctx->f_entropy = f_entropy;
+    ctx->p_entropy = p_entropy;
+
+    if (ctx->entropy_len == 0) {
+        /*
+         * See SP800-57 5.6.1 (p. 65-66) for the security strength provided by
+         * each hash function, then according to SP800-90A rev1 10.1 table 2,
+         * min_entropy_len (in bits) is security_strength.
+         *
+         * (This also matches the sizes used in the NIST test vectors.)
+         */
+        ctx->entropy_len = md_size <= 20 ? 16 : /* 160-bits hash -> 128 bits */
+                           md_size <= 28 ? 24 : /* 224-bits hash -> 192 bits */
+                           32;  /* better (256+) -> 256 bits */
+    }
+
+    if ((ret = hmac_drbg_reseed_core(ctx, custom, len,
+                                     1 /* add nonce */)) != 0) {
+        return ret;
+    }
+
+    return 0;
+}
+
+/*
+ * Set prediction resistance
+ */
+void mbedtls_hmac_drbg_set_prediction_resistance(mbedtls_hmac_drbg_context *ctx,
+                                                 int resistance)
+{
+    ctx->prediction_resistance = resistance;
+}
+
+/*
+ * Set entropy length grabbed for seeding
+ */
+void mbedtls_hmac_drbg_set_entropy_len(mbedtls_hmac_drbg_context *ctx, size_t len)
+{
+    ctx->entropy_len = len;
+}
+
+/*
+ * Set reseed interval
+ */
+void mbedtls_hmac_drbg_set_reseed_interval(mbedtls_hmac_drbg_context *ctx, int interval)
+{
+    ctx->reseed_interval = interval;
+}
+
+/*
+ * HMAC_DRBG random function with optional additional data:
+ * 10.1.2.5 (arabic) + 9.3 (Roman)
+ */
+int mbedtls_hmac_drbg_random_with_add(void *p_rng,
+                                      unsigned char *output, size_t out_len,
+                                      const unsigned char *additional, size_t add_len)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
+    size_t md_len = mbedtls_md_get_size(ctx->md_ctx.md_info);
+    size_t left = out_len;
+    unsigned char *out = output;
+
+    /* II. Check request length */
+    if (out_len > MBEDTLS_HMAC_DRBG_MAX_REQUEST) {
+        return MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG;
+    }
+
+    /* III. Check input length */
+    if (add_len > MBEDTLS_HMAC_DRBG_MAX_INPUT) {
+        return MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG;
+    }
+
+    /* 1. (aka VII and IX) Check reseed counter and PR */
+    if (ctx->f_entropy != NULL && /* For no-reseeding instances */
+        (ctx->prediction_resistance == MBEDTLS_HMAC_DRBG_PR_ON ||
+         ctx->reseed_counter > ctx->reseed_interval)) {
+        if ((ret = mbedtls_hmac_drbg_reseed(ctx, additional, add_len)) != 0) {
+            return ret;
+        }
+
+        add_len = 0; /* VII.4 */
+    }
+
+    /* 2. Use additional data if any */
+    if (additional != NULL && add_len != 0) {
+        if ((ret = mbedtls_hmac_drbg_update(ctx,
+                                            additional, add_len)) != 0) {
+            goto exit;
+        }
+    }
+
+    /* 3, 4, 5. Generate bytes */
+    while (left != 0) {
+        size_t use_len = left > md_len ? md_len : left;
+
+        if ((ret = mbedtls_md_hmac_reset(&ctx->md_ctx)) != 0) {
+            goto exit;
+        }
+        if ((ret = mbedtls_md_hmac_update(&ctx->md_ctx,
+                                          ctx->V, md_len)) != 0) {
+            goto exit;
+        }
+        if ((ret = mbedtls_md_hmac_finish(&ctx->md_ctx, ctx->V)) != 0) {
+            goto exit;
+        }
+
+        memcpy(out, ctx->V, use_len);
+        out += use_len;
+        left -= use_len;
+    }
+
+    /* 6. Update */
+    if ((ret = mbedtls_hmac_drbg_update(ctx,
+                                        additional, add_len)) != 0) {
+        goto exit;
+    }
+
+    /* 7. Update reseed counter */
+    ctx->reseed_counter++;
+
+exit:
+    /* 8. Done */
+    return ret;
+}
+
+/*
+ * HMAC_DRBG random function
+ */
+int mbedtls_hmac_drbg_random(void *p_rng, unsigned char *output, size_t out_len)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
+
+#if defined(MBEDTLS_THREADING_C)
+    if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0) {
+        return ret;
+    }
+#endif
+
+    ret = mbedtls_hmac_drbg_random_with_add(ctx, output, out_len, NULL, 0);
+
+#if defined(MBEDTLS_THREADING_C)
+    if (mbedtls_mutex_unlock(&ctx->mutex) != 0) {
+        return MBEDTLS_ERR_THREADING_MUTEX_ERROR;
+    }
+#endif
+
+    return ret;
+}
+
+/*
+ *  This function resets HMAC_DRBG context to the state immediately
+ *  after initial call of mbedtls_hmac_drbg_init().
+ */
+void mbedtls_hmac_drbg_free(mbedtls_hmac_drbg_context *ctx)
+{
+    if (ctx == NULL) {
+        return;
+    }
+
+#if defined(MBEDTLS_THREADING_C)
+    /* The mutex is initialized iff the md context is set up. */
+    if (ctx->md_ctx.md_info != NULL) {
+        mbedtls_mutex_free(&ctx->mutex);
+    }
+#endif
+    mbedtls_md_free(&ctx->md_ctx);
+    mbedtls_platform_zeroize(ctx, sizeof(mbedtls_hmac_drbg_context));
+    ctx->reseed_interval = MBEDTLS_HMAC_DRBG_RESEED_INTERVAL;
+}
+
+#if defined(MBEDTLS_FS_IO)
+int mbedtls_hmac_drbg_write_seed_file(mbedtls_hmac_drbg_context *ctx, const char *path)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    FILE *f;
+    unsigned char buf[MBEDTLS_HMAC_DRBG_MAX_INPUT];
+
+    if ((f = fopen(path, "wb")) == NULL) {
+        return MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
+    }
+
+    /* Ensure no stdio buffering of secrets, as such buffers cannot be wiped. */
+    mbedtls_setbuf(f, NULL);
+
+    if ((ret = mbedtls_hmac_drbg_random(ctx, buf, sizeof(buf))) != 0) {
+        goto exit;
+    }
+
+    if (fwrite(buf, 1, sizeof(buf), f) != sizeof(buf)) {
+        ret = MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
+        goto exit;
+    }
+
+    ret = 0;
+
+exit:
+    fclose(f);
+    mbedtls_platform_zeroize(buf, sizeof(buf));
+
+    return ret;
+}
+
+int mbedtls_hmac_drbg_update_seed_file(mbedtls_hmac_drbg_context *ctx, const char *path)
+{
+    int ret = 0;
+    FILE *f = NULL;
+    size_t n;
+    unsigned char buf[MBEDTLS_HMAC_DRBG_MAX_INPUT];
+    unsigned char c;
+
+    if ((f = fopen(path, "rb")) == NULL) {
+        return MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
+    }
+
+    /* Ensure no stdio buffering of secrets, as such buffers cannot be wiped. */
+    mbedtls_setbuf(f, NULL);
+
+    n = fread(buf, 1, sizeof(buf), f);
+    if (fread(&c, 1, 1, f) != 0) {
+        ret = MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG;
+        goto exit;
+    }
+    if (n == 0 || ferror(f)) {
+        ret = MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
+        goto exit;
+    }
+    fclose(f);
+    f = NULL;
+
+    ret = mbedtls_hmac_drbg_update(ctx, buf, n);
+
+exit:
+    mbedtls_platform_zeroize(buf, sizeof(buf));
+    if (f != NULL) {
+        fclose(f);
+    }
+    if (ret != 0) {
+        return ret;
+    }
+    return mbedtls_hmac_drbg_write_seed_file(ctx, path);
+}
+#endif /* MBEDTLS_FS_IO */
+
+
+#if defined(MBEDTLS_SELF_TEST)
+
+#if !defined(MBEDTLS_MD_CAN_SHA1)
+/* Dummy checkup routine */
+int mbedtls_hmac_drbg_self_test(int verbose)
+{
+    (void) verbose;
+    return 0;
+}
+#else
+
+#define OUTPUT_LEN  80
+
+/* From a NIST PR=true test vector */
+static const unsigned char entropy_pr[] = {
+    0xa0, 0xc9, 0xab, 0x58, 0xf1, 0xe2, 0xe5, 0xa4, 0xde, 0x3e, 0xbd, 0x4f,
+    0xf7, 0x3e, 0x9c, 0x5b, 0x64, 0xef, 0xd8, 0xca, 0x02, 0x8c, 0xf8, 0x11,
+    0x48, 0xa5, 0x84, 0xfe, 0x69, 0xab, 0x5a, 0xee, 0x42, 0xaa, 0x4d, 0x42,
+    0x17, 0x60, 0x99, 0xd4, 0x5e, 0x13, 0x97, 0xdc, 0x40, 0x4d, 0x86, 0xa3,
+    0x7b, 0xf5, 0x59, 0x54, 0x75, 0x69, 0x51, 0xe4
+};
+static const unsigned char result_pr[OUTPUT_LEN] = {
+    0x9a, 0x00, 0xa2, 0xd0, 0x0e, 0xd5, 0x9b, 0xfe, 0x31, 0xec, 0xb1, 0x39,
+    0x9b, 0x60, 0x81, 0x48, 0xd1, 0x96, 0x9d, 0x25, 0x0d, 0x3c, 0x1e, 0x94,
+    0x10, 0x10, 0x98, 0x12, 0x93, 0x25, 0xca, 0xb8, 0xfc, 0xcc, 0x2d, 0x54,
+    0x73, 0x19, 0x70, 0xc0, 0x10, 0x7a, 0xa4, 0x89, 0x25, 0x19, 0x95, 0x5e,
+    0x4b, 0xc6, 0x00, 0x1d, 0x7f, 0x4e, 0x6a, 0x2b, 0xf8, 0xa3, 0x01, 0xab,
+    0x46, 0x05, 0x5c, 0x09, 0xa6, 0x71, 0x88, 0xf1, 0xa7, 0x40, 0xee, 0xf3,
+    0xe1, 0x5c, 0x02, 0x9b, 0x44, 0xaf, 0x03, 0x44
+};
+
+/* From a NIST PR=false test vector */
+static const unsigned char entropy_nopr[] = {
+    0x79, 0x34, 0x9b, 0xbf, 0x7c, 0xdd, 0xa5, 0x79, 0x95, 0x57, 0x86, 0x66,
+    0x21, 0xc9, 0x13, 0x83, 0x11, 0x46, 0x73, 0x3a, 0xbf, 0x8c, 0x35, 0xc8,
+    0xc7, 0x21, 0x5b, 0x5b, 0x96, 0xc4, 0x8e, 0x9b, 0x33, 0x8c, 0x74, 0xe3,
+    0xe9, 0x9d, 0xfe, 0xdf
+};
+static const unsigned char result_nopr[OUTPUT_LEN] = {
+    0xc6, 0xa1, 0x6a, 0xb8, 0xd4, 0x20, 0x70, 0x6f, 0x0f, 0x34, 0xab, 0x7f,
+    0xec, 0x5a, 0xdc, 0xa9, 0xd8, 0xca, 0x3a, 0x13, 0x3e, 0x15, 0x9c, 0xa6,
+    0xac, 0x43, 0xc6, 0xf8, 0xa2, 0xbe, 0x22, 0x83, 0x4a, 0x4c, 0x0a, 0x0a,
+    0xff, 0xb1, 0x0d, 0x71, 0x94, 0xf1, 0xc1, 0xa5, 0xcf, 0x73, 0x22, 0xec,
+    0x1a, 0xe0, 0x96, 0x4e, 0xd4, 0xbf, 0x12, 0x27, 0x46, 0xe0, 0x87, 0xfd,
+    0xb5, 0xb3, 0xe9, 0x1b, 0x34, 0x93, 0xd5, 0xbb, 0x98, 0xfa, 0xed, 0x49,
+    0xe8, 0x5f, 0x13, 0x0f, 0xc8, 0xa4, 0x59, 0xb7
+};
+
+/* "Entropy" from buffer */
+static size_t test_offset;
+static int hmac_drbg_self_test_entropy(void *data,
+                                       unsigned char *buf, size_t len)
+{
+    const unsigned char *p = data;
+    memcpy(buf, p + test_offset, len);
+    test_offset += len;
+    return 0;
+}
+
+#define CHK(c)    if ((c) != 0)                          \
+    {                                       \
+        if (verbose != 0)                  \
+        mbedtls_printf("failed\n");  \
+        return 1;                        \
+    }
+
+/*
+ * Checkup routine for HMAC_DRBG with SHA-1
+ */
+int mbedtls_hmac_drbg_self_test(int verbose)
+{
+    mbedtls_hmac_drbg_context ctx;
+    unsigned char buf[OUTPUT_LEN];
+    const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type(MBEDTLS_MD_SHA1);
+
+    mbedtls_hmac_drbg_init(&ctx);
+
+    /*
+     * PR = True
+     */
+    if (verbose != 0) {
+        mbedtls_printf("  HMAC_DRBG (PR = True) : ");
+    }
+
+    test_offset = 0;
+    CHK(mbedtls_hmac_drbg_seed(&ctx, md_info,
+                               hmac_drbg_self_test_entropy, (void *) entropy_pr,
+                               NULL, 0));
+    mbedtls_hmac_drbg_set_prediction_resistance(&ctx, MBEDTLS_HMAC_DRBG_PR_ON);
+    CHK(mbedtls_hmac_drbg_random(&ctx, buf, OUTPUT_LEN));
+    CHK(mbedtls_hmac_drbg_random(&ctx, buf, OUTPUT_LEN));
+    CHK(memcmp(buf, result_pr, OUTPUT_LEN));
+    mbedtls_hmac_drbg_free(&ctx);
+
+    mbedtls_hmac_drbg_free(&ctx);
+
+    if (verbose != 0) {
+        mbedtls_printf("passed\n");
+    }
+
+    /*
+     * PR = False
+     */
+    if (verbose != 0) {
+        mbedtls_printf("  HMAC_DRBG (PR = False) : ");
+    }
+
+    mbedtls_hmac_drbg_init(&ctx);
+
+    test_offset = 0;
+    CHK(mbedtls_hmac_drbg_seed(&ctx, md_info,
+                               hmac_drbg_self_test_entropy, (void *) entropy_nopr,
+                               NULL, 0));
+    CHK(mbedtls_hmac_drbg_reseed(&ctx, NULL, 0));
+    CHK(mbedtls_hmac_drbg_random(&ctx, buf, OUTPUT_LEN));
+    CHK(mbedtls_hmac_drbg_random(&ctx, buf, OUTPUT_LEN));
+    CHK(memcmp(buf, result_nopr, OUTPUT_LEN));
+    mbedtls_hmac_drbg_free(&ctx);
+
+    mbedtls_hmac_drbg_free(&ctx);
+
+    if (verbose != 0) {
+        mbedtls_printf("passed\n");
+    }
+
+    if (verbose != 0) {
+        mbedtls_printf("\n");
+    }
+
+    return 0;
+}
+#endif /* MBEDTLS_MD_CAN_SHA1 */
+#endif /* MBEDTLS_SELF_TEST */
+
+#endif /* MBEDTLS_HMAC_DRBG_C */