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

git-subtree-dir: lib/mbedtls/external/mbedtls
git-subtree-split: 2ca6c285a0dd3f33982dd57299012dacab1ff206
diff --git a/tests/suites/test_suite_ecdsa.function b/tests/suites/test_suite_ecdsa.function
new file mode 100644
index 0000000..f16a6d4
--- /dev/null
+++ b/tests/suites/test_suite_ecdsa.function
@@ -0,0 +1,530 @@
+/* BEGIN_HEADER */
+#include "mbedtls/ecdsa.h"
+/* END_HEADER */
+
+/* BEGIN_DEPENDENCIES
+ * depends_on:MBEDTLS_ECDSA_C
+ * END_DEPENDENCIES
+ */
+
+/* BEGIN_CASE */
+void ecdsa_prim_zero(int id)
+{
+    mbedtls_ecp_group grp;
+    mbedtls_ecp_point Q;
+    mbedtls_mpi d, r, s;
+    mbedtls_test_rnd_pseudo_info rnd_info;
+    unsigned char buf[MBEDTLS_MD_MAX_SIZE];
+
+    mbedtls_ecp_group_init(&grp);
+    mbedtls_ecp_point_init(&Q);
+    mbedtls_mpi_init(&d); mbedtls_mpi_init(&r); mbedtls_mpi_init(&s);
+    memset(&rnd_info, 0x00, sizeof(mbedtls_test_rnd_pseudo_info));
+    memset(buf, 0, sizeof(buf));
+
+    TEST_ASSERT(mbedtls_ecp_group_load(&grp, id) == 0);
+    TEST_ASSERT(mbedtls_ecp_gen_keypair(&grp, &d, &Q,
+                                        &mbedtls_test_rnd_pseudo_rand,
+                                        &rnd_info) == 0);
+
+    TEST_ASSERT(mbedtls_ecdsa_sign(&grp, &r, &s, &d, buf, sizeof(buf),
+                                   &mbedtls_test_rnd_pseudo_rand,
+                                   &rnd_info) == 0);
+    TEST_ASSERT(mbedtls_ecdsa_verify(&grp, buf, sizeof(buf), &Q, &r, &s) == 0);
+
+exit:
+    mbedtls_ecp_group_free(&grp);
+    mbedtls_ecp_point_free(&Q);
+    mbedtls_mpi_free(&d); mbedtls_mpi_free(&r); mbedtls_mpi_free(&s);
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void ecdsa_prim_random(int id)
+{
+    mbedtls_ecp_group grp;
+    mbedtls_ecp_point Q;
+    mbedtls_mpi d, r, s;
+    mbedtls_test_rnd_pseudo_info rnd_info;
+    unsigned char buf[MBEDTLS_MD_MAX_SIZE];
+
+    mbedtls_ecp_group_init(&grp);
+    mbedtls_ecp_point_init(&Q);
+    mbedtls_mpi_init(&d); mbedtls_mpi_init(&r); mbedtls_mpi_init(&s);
+    memset(&rnd_info, 0x00, sizeof(mbedtls_test_rnd_pseudo_info));
+    memset(buf, 0, sizeof(buf));
+
+    /* prepare material for signature */
+    TEST_ASSERT(mbedtls_test_rnd_pseudo_rand(&rnd_info,
+                                             buf, sizeof(buf)) == 0);
+    TEST_ASSERT(mbedtls_ecp_group_load(&grp, id) == 0);
+    TEST_ASSERT(mbedtls_ecp_gen_keypair(&grp, &d, &Q,
+                                        &mbedtls_test_rnd_pseudo_rand,
+                                        &rnd_info) == 0);
+
+    TEST_ASSERT(mbedtls_ecdsa_sign(&grp, &r, &s, &d, buf, sizeof(buf),
+                                   &mbedtls_test_rnd_pseudo_rand,
+                                   &rnd_info) == 0);
+    TEST_ASSERT(mbedtls_ecdsa_verify(&grp, buf, sizeof(buf), &Q, &r, &s) == 0);
+
+exit:
+    mbedtls_ecp_group_free(&grp);
+    mbedtls_ecp_point_free(&Q);
+    mbedtls_mpi_free(&d); mbedtls_mpi_free(&r); mbedtls_mpi_free(&s);
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void ecdsa_prim_test_vectors(int id, char *d_str, char *xQ_str,
+                             char *yQ_str, data_t *rnd_buf,
+                             data_t *hash, char *r_str, char *s_str,
+                             int result)
+{
+    mbedtls_ecp_group grp;
+    mbedtls_ecp_point Q;
+    mbedtls_mpi d, r, s, r_check, s_check, zero;
+    mbedtls_test_rnd_buf_info rnd_info;
+
+    mbedtls_ecp_group_init(&grp);
+    mbedtls_ecp_point_init(&Q);
+    mbedtls_mpi_init(&d); mbedtls_mpi_init(&r); mbedtls_mpi_init(&s);
+    mbedtls_mpi_init(&r_check); mbedtls_mpi_init(&s_check);
+    mbedtls_mpi_init(&zero);
+
+    TEST_ASSERT(mbedtls_ecp_group_load(&grp, id) == 0);
+    TEST_ASSERT(mbedtls_ecp_point_read_string(&Q, 16, xQ_str, yQ_str) == 0);
+    TEST_ASSERT(mbedtls_test_read_mpi(&d, d_str) == 0);
+    TEST_ASSERT(mbedtls_test_read_mpi(&r_check, r_str) == 0);
+    TEST_ASSERT(mbedtls_test_read_mpi(&s_check, s_str) == 0);
+    rnd_info.fallback_f_rng = mbedtls_test_rnd_std_rand;
+    rnd_info.fallback_p_rng = NULL;
+    rnd_info.buf = rnd_buf->x;
+    rnd_info.length = rnd_buf->len;
+
+    /* Fix rnd_buf->x by shifting it left if necessary */
+    if (grp.nbits % 8 != 0) {
+        unsigned char shift = 8 - (grp.nbits % 8);
+        size_t i;
+
+        for (i = 0; i < rnd_info.length - 1; i++) {
+            rnd_buf->x[i] = rnd_buf->x[i] << shift | rnd_buf->x[i+1] >> (8 - shift);
+        }
+
+        rnd_buf->x[rnd_info.length-1] <<= shift;
+    }
+
+    TEST_ASSERT(mbedtls_ecdsa_sign(&grp, &r, &s, &d, hash->x, hash->len,
+                                   mbedtls_test_rnd_buffer_rand, &rnd_info) == result);
+
+    if (result == 0) {
+        /* Check we generated the expected values */
+        TEST_EQUAL(mbedtls_mpi_cmp_mpi(&r, &r_check), 0);
+        TEST_EQUAL(mbedtls_mpi_cmp_mpi(&s, &s_check), 0);
+
+        /* Valid signature */
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len,
+                                        &Q, &r_check, &s_check), 0);
+
+        /* Invalid signature: wrong public key (G instead of Q) */
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len,
+                                        &grp.G, &r_check, &s_check), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+
+        /* Invalid signatures: r or s or both one off */
+        TEST_EQUAL(mbedtls_mpi_sub_int(&r, &r_check, 1), 0);
+        TEST_EQUAL(mbedtls_mpi_add_int(&s, &s_check, 1), 0);
+
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r, &s_check), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r_check, &s), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r, &s), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+
+        /* Invalid signatures: r, s or both (CVE-2022-21449) are zero */
+        TEST_EQUAL(mbedtls_mpi_lset(&zero, 0), 0);
+
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &zero, &s_check), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r_check, &zero), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &zero, &zero), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+
+        /* Invalid signatures: r, s or both are == N */
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &grp.N, &s_check), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r_check, &grp.N), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &grp.N, &grp.N), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+
+        /* Invalid signatures: r, s or both are negative */
+        TEST_EQUAL(mbedtls_mpi_sub_mpi(&r, &r_check, &grp.N), 0);
+        TEST_EQUAL(mbedtls_mpi_sub_mpi(&s, &s_check, &grp.N), 0);
+
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r, &s_check), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r_check, &s), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r, &s), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+
+        /* Invalid signatures: r or s or both are > N */
+        TEST_EQUAL(mbedtls_mpi_add_mpi(&r, &r_check, &grp.N), 0);
+        TEST_EQUAL(mbedtls_mpi_add_mpi(&s, &s_check, &grp.N), 0);
+
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r, &s_check), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r_check, &s), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+        TEST_EQUAL(mbedtls_ecdsa_verify(&grp, hash->x, hash->len, &Q,
+                                        &r, &s), MBEDTLS_ERR_ECP_VERIFY_FAILED);
+    }
+
+exit:
+    mbedtls_ecp_group_free(&grp);
+    mbedtls_ecp_point_free(&Q);
+    mbedtls_mpi_free(&d); mbedtls_mpi_free(&r); mbedtls_mpi_free(&s);
+    mbedtls_mpi_free(&r_check); mbedtls_mpi_free(&s_check);
+    mbedtls_mpi_free(&zero);
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ECDSA_DETERMINISTIC */
+void ecdsa_det_test_vectors(int id, char *d_str, int md_alg, data_t *hash,
+                            char *r_str, char *s_str)
+{
+    mbedtls_ecp_group grp;
+    mbedtls_mpi d, r, s, r_check, s_check;
+
+    MD_PSA_INIT();
+
+    mbedtls_ecp_group_init(&grp);
+    mbedtls_mpi_init(&d); mbedtls_mpi_init(&r); mbedtls_mpi_init(&s);
+    mbedtls_mpi_init(&r_check); mbedtls_mpi_init(&s_check);
+
+    TEST_ASSERT(mbedtls_ecp_group_load(&grp, id) == 0);
+    TEST_ASSERT(mbedtls_test_read_mpi(&d, d_str) == 0);
+    TEST_ASSERT(mbedtls_test_read_mpi(&r_check, r_str) == 0);
+    TEST_ASSERT(mbedtls_test_read_mpi(&s_check, s_str) == 0);
+
+    TEST_ASSERT(
+        mbedtls_ecdsa_sign_det_ext(&grp, &r, &s, &d,
+                                   hash->x, hash->len, md_alg,
+                                   mbedtls_test_rnd_std_rand,
+                                   NULL)
+        == 0);
+
+    TEST_ASSERT(mbedtls_mpi_cmp_mpi(&r, &r_check) == 0);
+    TEST_ASSERT(mbedtls_mpi_cmp_mpi(&s, &s_check) == 0);
+
+exit:
+    mbedtls_ecp_group_free(&grp);
+    mbedtls_mpi_free(&d); mbedtls_mpi_free(&r); mbedtls_mpi_free(&s);
+    mbedtls_mpi_free(&r_check); mbedtls_mpi_free(&s_check);
+    MD_PSA_DONE();
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_MD_CAN_SHA256 */
+void ecdsa_write_read_zero(int id)
+{
+    mbedtls_ecdsa_context ctx;
+    mbedtls_test_rnd_pseudo_info rnd_info;
+    unsigned char hash[32];
+    unsigned char sig[200];
+    size_t sig_len, i;
+
+    MD_PSA_INIT();
+
+    mbedtls_ecdsa_init(&ctx);
+    memset(&rnd_info, 0x00, sizeof(mbedtls_test_rnd_pseudo_info));
+    memset(hash, 0, sizeof(hash));
+    memset(sig, 0x2a, sizeof(sig));
+
+    /* generate signing key */
+    TEST_ASSERT(mbedtls_ecdsa_genkey(&ctx, id,
+                                     &mbedtls_test_rnd_pseudo_rand,
+                                     &rnd_info) == 0);
+
+    /* generate and write signature, then read and verify it */
+    TEST_ASSERT(mbedtls_ecdsa_write_signature(&ctx, MBEDTLS_MD_SHA256,
+                                              hash, sizeof(hash),
+                                              sig, sizeof(sig), &sig_len,
+                                              &mbedtls_test_rnd_pseudo_rand,
+                                              &rnd_info) == 0);
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len) == 0);
+
+    /* check we didn't write past the announced length */
+    for (i = sig_len; i < sizeof(sig); i++) {
+        TEST_ASSERT(sig[i] == 0x2a);
+    }
+
+    /* try verification with invalid length */
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len - 1) != 0);
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len + 1) != 0);
+
+    /* try invalid sequence tag */
+    sig[0]++;
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len) != 0);
+    sig[0]--;
+
+    /* try modifying r */
+    sig[10]++;
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len) == MBEDTLS_ERR_ECP_VERIFY_FAILED);
+    sig[10]--;
+
+    /* try modifying s */
+    sig[sig_len - 1]++;
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len) == MBEDTLS_ERR_ECP_VERIFY_FAILED);
+    sig[sig_len - 1]--;
+
+exit:
+    mbedtls_ecdsa_free(&ctx);
+    MD_PSA_DONE();
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_MD_CAN_SHA256 */
+void ecdsa_write_read_random(int id)
+{
+    mbedtls_ecdsa_context ctx;
+    mbedtls_test_rnd_pseudo_info rnd_info;
+    unsigned char hash[32];
+    unsigned char sig[200];
+    size_t sig_len, i;
+
+    MD_PSA_INIT();
+
+    mbedtls_ecdsa_init(&ctx);
+    memset(&rnd_info, 0x00, sizeof(mbedtls_test_rnd_pseudo_info));
+    memset(hash, 0, sizeof(hash));
+    memset(sig, 0x2a, sizeof(sig));
+
+    /* prepare material for signature */
+    TEST_ASSERT(mbedtls_test_rnd_pseudo_rand(&rnd_info,
+                                             hash, sizeof(hash)) == 0);
+
+    /* generate signing key */
+    TEST_ASSERT(mbedtls_ecdsa_genkey(&ctx, id,
+                                     &mbedtls_test_rnd_pseudo_rand,
+                                     &rnd_info) == 0);
+
+    /* generate and write signature, then read and verify it */
+    TEST_ASSERT(mbedtls_ecdsa_write_signature(&ctx, MBEDTLS_MD_SHA256,
+                                              hash, sizeof(hash),
+                                              sig, sizeof(sig), &sig_len,
+                                              &mbedtls_test_rnd_pseudo_rand,
+                                              &rnd_info) == 0);
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len) == 0);
+
+    /* check we didn't write past the announced length */
+    for (i = sig_len; i < sizeof(sig); i++) {
+        TEST_ASSERT(sig[i] == 0x2a);
+    }
+
+    /* try verification with invalid length */
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len - 1) != 0);
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len + 1) != 0);
+
+    /* try invalid sequence tag */
+    sig[0]++;
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len) != 0);
+    sig[0]--;
+
+    /* try modifying r */
+    sig[10]++;
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len) == MBEDTLS_ERR_ECP_VERIFY_FAILED);
+    sig[10]--;
+
+    /* try modifying s */
+    sig[sig_len - 1]++;
+    TEST_ASSERT(mbedtls_ecdsa_read_signature(&ctx, hash, sizeof(hash),
+                                             sig, sig_len) == MBEDTLS_ERR_ECP_VERIFY_FAILED);
+    sig[sig_len - 1]--;
+
+exit:
+    mbedtls_ecdsa_free(&ctx);
+    MD_PSA_DONE();
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_RESTARTABLE */
+void ecdsa_read_restart(int id, data_t *pk, data_t *hash, data_t *sig,
+                        int max_ops, int min_restart, int max_restart)
+{
+    mbedtls_ecdsa_context ctx;
+    mbedtls_ecdsa_restart_ctx rs_ctx;
+    int ret, cnt_restart;
+
+    mbedtls_ecdsa_init(&ctx);
+    mbedtls_ecdsa_restart_init(&rs_ctx);
+
+    TEST_ASSERT(mbedtls_ecp_group_load(&ctx.grp, id) == 0);
+    TEST_ASSERT(mbedtls_ecp_point_read_binary(&ctx.grp, &ctx.Q,
+                                              pk->x, pk->len) == 0);
+
+    mbedtls_ecp_set_max_ops(max_ops);
+
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_ecdsa_read_signature_restartable(&ctx,
+                                                       hash->x, hash->len, sig->x, sig->len,
+                                                       &rs_ctx);
+    } while (ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart);
+
+    TEST_ASSERT(ret == 0);
+    TEST_ASSERT(cnt_restart >= min_restart);
+    TEST_ASSERT(cnt_restart <= max_restart);
+
+    /* try modifying r */
+
+    TEST_ASSERT(sig->len > 10);
+    sig->x[10]++;
+    do {
+        ret = mbedtls_ecdsa_read_signature_restartable(&ctx,
+                                                       hash->x, hash->len, sig->x, sig->len,
+                                                       &rs_ctx);
+    } while (ret == MBEDTLS_ERR_ECP_IN_PROGRESS);
+    TEST_ASSERT(ret == MBEDTLS_ERR_ECP_VERIFY_FAILED);
+    sig->x[10]--;
+
+    /* try modifying s */
+    sig->x[sig->len - 1]++;
+    do {
+        ret = mbedtls_ecdsa_read_signature_restartable(&ctx,
+                                                       hash->x, hash->len, sig->x, sig->len,
+                                                       &rs_ctx);
+    } while (ret == MBEDTLS_ERR_ECP_IN_PROGRESS);
+    TEST_ASSERT(ret == MBEDTLS_ERR_ECP_VERIFY_FAILED);
+    sig->x[sig->len - 1]--;
+
+    /* Do we leak memory when aborting an operation?
+     * This test only makes sense when we actually restart */
+    if (min_restart > 0) {
+        ret = mbedtls_ecdsa_read_signature_restartable(&ctx,
+                                                       hash->x, hash->len, sig->x, sig->len,
+                                                       &rs_ctx);
+        TEST_ASSERT(ret == MBEDTLS_ERR_ECP_IN_PROGRESS);
+    }
+
+exit:
+    mbedtls_ecdsa_free(&ctx);
+    mbedtls_ecdsa_restart_free(&rs_ctx);
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_RESTARTABLE:MBEDTLS_ECDSA_DETERMINISTIC */
+void ecdsa_write_restart(int id, char *d_str, int md_alg,
+                         data_t *hash, data_t *sig_check,
+                         int max_ops, int min_restart, int max_restart)
+{
+    int ret, cnt_restart;
+    mbedtls_ecdsa_restart_ctx rs_ctx;
+    mbedtls_ecdsa_context ctx;
+    unsigned char sig[MBEDTLS_ECDSA_MAX_LEN];
+    size_t slen;
+
+    MD_PSA_INIT();
+
+    mbedtls_ecdsa_restart_init(&rs_ctx);
+    mbedtls_ecdsa_init(&ctx);
+    memset(sig, 0, sizeof(sig));
+
+    TEST_ASSERT(mbedtls_ecp_group_load(&ctx.grp, id) == 0);
+    TEST_ASSERT(mbedtls_test_read_mpi(&ctx.d, d_str) == 0);
+
+    mbedtls_ecp_set_max_ops(max_ops);
+
+    slen = sizeof(sig);
+    cnt_restart = 0;
+    do {
+        ret = mbedtls_ecdsa_write_signature_restartable(&ctx,
+                                                        md_alg,
+                                                        hash->x,
+                                                        hash->len,
+                                                        sig,
+                                                        sizeof(sig),
+                                                        &slen,
+                                                        mbedtls_test_rnd_std_rand,
+                                                        NULL,
+                                                        &rs_ctx);
+    } while (ret == MBEDTLS_ERR_ECP_IN_PROGRESS && ++cnt_restart);
+
+    TEST_ASSERT(ret == 0);
+    TEST_ASSERT(slen == sig_check->len);
+    TEST_ASSERT(memcmp(sig, sig_check->x, slen) == 0);
+
+    TEST_ASSERT(cnt_restart >= min_restart);
+    TEST_ASSERT(cnt_restart <= max_restart);
+
+    /* Do we leak memory when aborting an operation?
+     * This test only makes sense when we actually restart */
+    if (min_restart > 0) {
+        ret = mbedtls_ecdsa_write_signature_restartable(&ctx,
+                                                        md_alg,
+                                                        hash->x,
+                                                        hash->len,
+                                                        sig,
+                                                        sizeof(sig),
+                                                        &slen,
+                                                        mbedtls_test_rnd_std_rand,
+                                                        NULL,
+                                                        &rs_ctx);
+        TEST_ASSERT(ret == MBEDTLS_ERR_ECP_IN_PROGRESS);
+    }
+
+exit:
+    mbedtls_ecdsa_restart_free(&rs_ctx);
+    mbedtls_ecdsa_free(&ctx);
+    MD_PSA_DONE();
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void ecdsa_verify(int grp_id, char *x, char *y, char *r, char *s, data_t *content, int expected)
+{
+    mbedtls_ecdsa_context ctx;
+    mbedtls_mpi sig_r, sig_s;
+
+    mbedtls_ecdsa_init(&ctx);
+    mbedtls_mpi_init(&sig_r);
+    mbedtls_mpi_init(&sig_s);
+
+    /* Prepare ECP group context */
+    TEST_EQUAL(mbedtls_ecp_group_load(&ctx.grp, grp_id), 0);
+
+    /* Prepare public key */
+    TEST_EQUAL(mbedtls_test_read_mpi(&ctx.Q.X, x), 0);
+    TEST_EQUAL(mbedtls_test_read_mpi(&ctx.Q.Y, y), 0);
+    TEST_EQUAL(mbedtls_mpi_lset(&ctx.Q.Z, 1), 0);
+
+    /* Prepare signature R & S */
+    TEST_EQUAL(mbedtls_test_read_mpi(&sig_r, r), 0);
+    TEST_EQUAL(mbedtls_test_read_mpi(&sig_s, s), 0);
+
+    /* Test whether public key has expected validity */
+    TEST_EQUAL(mbedtls_ecp_check_pubkey(&ctx.grp, &ctx.Q),
+               expected == MBEDTLS_ERR_ECP_INVALID_KEY ? MBEDTLS_ERR_ECP_INVALID_KEY : 0);
+
+    /* Verification */
+    int result = mbedtls_ecdsa_verify(&ctx.grp, content->x, content->len, &ctx.Q, &sig_r, &sig_s);
+
+    TEST_EQUAL(result, expected);
+exit:
+    mbedtls_ecdsa_free(&ctx);
+    mbedtls_mpi_free(&sig_r);
+    mbedtls_mpi_free(&sig_s);
+}
+/* END_CASE */