Add selftests to validate the ECDSA signature verification kfuncs introduced in the BPF crypto subsystem. The tests verify both valid signature acceptance and invalid signature rejection using the context-based ECDSA API.
The tests use RFC 6979 test vectors for NIST P-256 (secp256r1) with well-known valid signatures. The algorithm "p1363(ecdsa-nist-p256)" is used to handle standard r||s signature format.
Signed-off-by: Daniel Hodges git@danielhodges.dev --- .../selftests/bpf/prog_tests/ecdsa_verify.c | 96 ++++++++ .../selftests/bpf/progs/ecdsa_verify.c | 228 ++++++++++++++++++ 2 files changed, 324 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/ecdsa_verify.c create mode 100644 tools/testing/selftests/bpf/progs/ecdsa_verify.c
diff --git a/tools/testing/selftests/bpf/prog_tests/ecdsa_verify.c b/tools/testing/selftests/bpf/prog_tests/ecdsa_verify.c new file mode 100644 index 000000000000..d1f83ce08ad6 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/ecdsa_verify.c @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <test_progs.h> +#include "ecdsa_verify.skel.h" + +static void test_ecdsa_verify_valid_signature(void) +{ + struct ecdsa_verify *skel; + int err, prog_fd; + + LIBBPF_OPTS(bpf_test_run_opts, topts); + + skel = ecdsa_verify__open_and_load(); + if (!ASSERT_OK_PTR(skel, "ecdsa_verify__open_and_load")) + return; + + prog_fd = bpf_program__fd(skel->progs.test_ecdsa_verify_valid); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_ecdsa_verify_valid"); + ASSERT_EQ(skel->data->ctx_create_status, 0, "ctx_create_status"); + ASSERT_EQ(skel->data->verify_result, 0, "verify_valid_signature"); + + ecdsa_verify__destroy(skel); +} + +static void test_ecdsa_verify_invalid_signature(void) +{ + struct ecdsa_verify *skel; + int err, prog_fd; + + LIBBPF_OPTS(bpf_test_run_opts, topts); + + skel = ecdsa_verify__open_and_load(); + if (!ASSERT_OK_PTR(skel, "ecdsa_verify__open_and_load")) + return; + + prog_fd = bpf_program__fd(skel->progs.test_ecdsa_verify_invalid); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_ecdsa_verify_invalid"); + ASSERT_NEQ(skel->data->verify_invalid_result, 0, "verify_invalid_signature_rejected"); + + ecdsa_verify__destroy(skel); +} + +static void test_ecdsa_sign_and_verify(void) +{ + struct ecdsa_verify *skel; + int err, prog_fd; + + LIBBPF_OPTS(bpf_test_run_opts, topts); + + skel = ecdsa_verify__open_and_load(); + if (!ASSERT_OK_PTR(skel, "ecdsa_verify__open_and_load")) + return; + + prog_fd = bpf_program__fd(skel->progs.test_ecdsa_sign_verify); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_ecdsa_sign_verify"); + ASSERT_GT(skel->data->sign_result, 0, "sign_returns_signature_size"); + ASSERT_EQ(skel->data->sign_verify_result, 0, "verify_generated_signature"); + + ecdsa_verify__destroy(skel); +} + +static void test_ecdsa_size_queries(void) +{ + struct ecdsa_verify *skel; + int err, prog_fd; + + LIBBPF_OPTS(bpf_test_run_opts, topts); + + skel = ecdsa_verify__open_and_load(); + if (!ASSERT_OK_PTR(skel, "ecdsa_verify__open_and_load")) + return; + + prog_fd = bpf_program__fd(skel->progs.test_ecdsa_size_queries); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_ecdsa_size_queries"); + ASSERT_EQ(skel->data->keysize_result, 256, "keysize_p256"); + ASSERT_EQ(skel->data->digestsize_result, 64, "digestsize_p256"); + ASSERT_EQ(skel->data->maxsize_result, 64, "maxsize_p256"); + + ecdsa_verify__destroy(skel); +} + +void test_ecdsa_verify(void) +{ + if (test__start_subtest("verify_valid_signature")) + test_ecdsa_verify_valid_signature(); + if (test__start_subtest("verify_invalid_signature")) + test_ecdsa_verify_invalid_signature(); + if (test__start_subtest("sign_and_verify")) + test_ecdsa_sign_and_verify(); + if (test__start_subtest("size_queries")) + test_ecdsa_size_queries(); +} diff --git a/tools/testing/selftests/bpf/progs/ecdsa_verify.c b/tools/testing/selftests/bpf/progs/ecdsa_verify.c new file mode 100644 index 000000000000..fb24baf6c437 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/ecdsa_verify.c @@ -0,0 +1,228 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +struct bpf_ecdsa_ctx; +extern struct bpf_ecdsa_ctx * +bpf_ecdsa_ctx_create(const struct bpf_dynptr *algo_name, + const struct bpf_dynptr *public_key, int *err) __ksym; +extern struct bpf_ecdsa_ctx * +bpf_ecdsa_ctx_create_with_privkey(const struct bpf_dynptr *algo_name, + const struct bpf_dynptr *private_key, int *err) __ksym; +extern int bpf_ecdsa_verify(struct bpf_ecdsa_ctx *ctx, + const struct bpf_dynptr *message, + const struct bpf_dynptr *signature) __ksym; +extern int bpf_ecdsa_sign(struct bpf_ecdsa_ctx *ctx, + const struct bpf_dynptr *message, + const struct bpf_dynptr *signature) __ksym; +extern int bpf_ecdsa_keysize(struct bpf_ecdsa_ctx *ctx) __ksym; +extern int bpf_ecdsa_digestsize(struct bpf_ecdsa_ctx *ctx) __ksym; +extern int bpf_ecdsa_maxsize(struct bpf_ecdsa_ctx *ctx) __ksym; +extern void bpf_ecdsa_ctx_release(struct bpf_ecdsa_ctx *ctx) __ksym; + +/* NIST P-256 test vector + * This is a known valid ECDSA signature for testing purposes + */ + +/* Algorithm name for P-256 with p1363 format (standard r||s signature) */ +char algo_p256[] = "p1363(ecdsa-nist-p256)"; + +/* Public key in uncompressed format: 0x04 || x || y (65 bytes) */ +unsigned char pubkey_p256[65] = { + 0x04, /* Uncompressed point indicator */ + /* X coordinate (32 bytes) */ + 0x60, 0xfe, 0xd4, 0xba, 0x25, 0x5a, 0x9d, 0x31, + 0xc9, 0x61, 0xeb, 0x74, 0xc6, 0x35, 0x6d, 0x68, + 0xc0, 0x49, 0xb8, 0x92, 0x3b, 0x61, 0xfa, 0x6c, + 0xe6, 0x69, 0x62, 0x2e, 0x60, 0xf2, 0x9f, 0xb6, + /* Y coordinate (32 bytes) */ + 0x79, 0x03, 0xfe, 0x10, 0x08, 0xb8, 0xbc, 0x99, + 0xa4, 0x1a, 0xe9, 0xe9, 0x56, 0x28, 0xbc, 0x64, + 0xf2, 0xf1, 0xb2, 0x0c, 0x2d, 0x7e, 0x9f, 0x51, + 0x77, 0xa3, 0xc2, 0x94, 0xd4, 0x46, 0x22, 0x99 +}; + +/* Message hash (32 bytes) - SHA-256 of "sample" */ +unsigned char message_hash[32] = { + 0xaf, 0x2b, 0xdb, 0xe1, 0xaa, 0x9b, 0x6e, 0xc1, + 0xe2, 0xad, 0xe1, 0xd6, 0x94, 0xf4, 0x1f, 0xc7, + 0x1a, 0x83, 0x1d, 0x02, 0x68, 0xe9, 0x89, 0x15, + 0x62, 0x11, 0x3d, 0x8a, 0x62, 0xad, 0xd1, 0xbf +}; + +/* Valid signature r || s (64 bytes) */ +unsigned char valid_signature[64] = { + /* r component (32 bytes) */ + 0xef, 0xd4, 0x8b, 0x2a, 0xac, 0xb6, 0xa8, 0xfd, + 0x11, 0x40, 0xdd, 0x9c, 0xd4, 0x5e, 0x81, 0xd6, + 0x9d, 0x2c, 0x87, 0x7b, 0x56, 0xaa, 0xf9, 0x91, + 0xc3, 0x4d, 0x0e, 0xa8, 0x4e, 0xaf, 0x37, 0x16, + /* s component (32 bytes) */ + 0xf7, 0xcb, 0x1c, 0x94, 0x2d, 0x65, 0x7c, 0x41, + 0xd4, 0x36, 0xc7, 0xa1, 0xb6, 0xe2, 0x9f, 0x65, + 0xf3, 0xe9, 0x00, 0xdb, 0xb9, 0xaf, 0xf4, 0x06, + 0x4d, 0xc4, 0xab, 0x2f, 0x84, 0x3a, 0xcd, 0xa8 +}; + +/* Invalid signature (modified r component) for negative test */ +unsigned char invalid_signature[64] = { + /* r component (32 bytes) - first byte modified */ + 0xff, 0xd4, 0x8b, 0x2a, 0xac, 0xb6, 0xa8, 0xfd, + 0x11, 0x40, 0xdd, 0x9c, 0xd4, 0x5e, 0x81, 0xd6, + 0x9d, 0x2c, 0x87, 0x7b, 0x56, 0xaa, 0xf9, 0x91, + 0xc3, 0x4d, 0x0e, 0xa8, 0x4e, 0xaf, 0x37, 0x16, + /* s component (32 bytes) */ + 0xf7, 0xcb, 0x1c, 0x94, 0x2d, 0x65, 0x7c, 0x41, + 0xd4, 0x36, 0xc7, 0xa1, 0xb6, 0xe2, 0x9f, 0x65, + 0xf3, 0xe9, 0x00, 0xdb, 0xb9, 0xaf, 0xf4, 0x06, + 0x4d, 0xc4, 0xab, 0x2f, 0x84, 0x3a, 0xcd, 0xa8 +}; + +/* Private key for signing (32 bytes) - matches the public key above */ +unsigned char privkey_p256[32] = { + 0xc9, 0xaf, 0xa9, 0xd8, 0x45, 0xba, 0x75, 0x16, + 0x6b, 0x5c, 0x21, 0x57, 0x67, 0xb1, 0xd6, 0x93, + 0x4e, 0x50, 0xc3, 0xdb, 0x36, 0xe8, 0x9b, 0x12, + 0x7b, 0x8a, 0x62, 0x2b, 0x12, 0x0f, 0x67, 0x21 +}; + +/* Test results */ +int verify_result = -1; +int verify_invalid_result = -1; +int ctx_create_status = -1; +int sign_result = -1; +int sign_verify_result = -1; +int keysize_result = -1; +int digestsize_result = -1; +int maxsize_result = -1; +unsigned char generated_signature[64] = {0}; + +SEC("syscall") +int test_ecdsa_verify_valid(void *ctx) +{ + struct bpf_ecdsa_ctx *ecdsa_ctx; + struct bpf_dynptr algo_ptr, key_ptr, msg_ptr, sig_ptr; + int err = 0; + + bpf_dynptr_from_mem(algo_p256, sizeof(algo_p256) - 1, 0, &algo_ptr); + bpf_dynptr_from_mem(pubkey_p256, sizeof(pubkey_p256), 0, &key_ptr); + + ecdsa_ctx = bpf_ecdsa_ctx_create(&algo_ptr, &key_ptr, &err); + if (!ecdsa_ctx) { + ctx_create_status = err; + return 0; + } + ctx_create_status = 0; + + bpf_dynptr_from_mem(message_hash, sizeof(message_hash), 0, &msg_ptr); + bpf_dynptr_from_mem(valid_signature, sizeof(valid_signature), 0, &sig_ptr); + + verify_result = bpf_ecdsa_verify(ecdsa_ctx, &msg_ptr, &sig_ptr); + + bpf_ecdsa_ctx_release(ecdsa_ctx); + + return 0; +} + +SEC("syscall") +int test_ecdsa_verify_invalid(void *ctx) +{ + struct bpf_ecdsa_ctx *ecdsa_ctx; + struct bpf_dynptr algo_ptr, key_ptr, msg_ptr, sig_ptr; + int err = 0; + + bpf_dynptr_from_mem(algo_p256, sizeof(algo_p256) - 1, 0, &algo_ptr); + bpf_dynptr_from_mem(pubkey_p256, sizeof(pubkey_p256), 0, &key_ptr); + + ecdsa_ctx = bpf_ecdsa_ctx_create(&algo_ptr, &key_ptr, &err); + if (!ecdsa_ctx) + return 0; + + bpf_dynptr_from_mem(message_hash, sizeof(message_hash), 0, &msg_ptr); + bpf_dynptr_from_mem(invalid_signature, sizeof(invalid_signature), 0, &sig_ptr); + + verify_invalid_result = bpf_ecdsa_verify(ecdsa_ctx, &msg_ptr, &sig_ptr); + + bpf_ecdsa_ctx_release(ecdsa_ctx); + + return 0; +} + +SEC("syscall") +int test_ecdsa_sign_verify(void *ctx) +{ + struct bpf_ecdsa_ctx *sign_ctx, *verify_ctx; + struct bpf_dynptr algo_ptr, privkey_ptr, pubkey_ptr, msg_ptr, sig_ptr; + int err = 0; + + /* Create signing context with private key */ + bpf_dynptr_from_mem(algo_p256, sizeof(algo_p256) - 1, 0, &algo_ptr); + bpf_dynptr_from_mem(privkey_p256, sizeof(privkey_p256), 0, &privkey_ptr); + + sign_ctx = bpf_ecdsa_ctx_create_with_privkey(&algo_ptr, &privkey_ptr, &err); + if (!sign_ctx) { + sign_result = err; + return 0; + } + + /* Sign the message */ + bpf_dynptr_from_mem(message_hash, sizeof(message_hash), 0, &msg_ptr); + bpf_dynptr_from_mem(generated_signature, sizeof(generated_signature), 0, &sig_ptr); + + sign_result = bpf_ecdsa_sign(sign_ctx, &msg_ptr, &sig_ptr); + + bpf_ecdsa_ctx_release(sign_ctx); + + /* If signing succeeded, verify the generated signature */ + if (sign_result > 0 && sign_result <= (int)sizeof(generated_signature)) { + unsigned int sig_size; + + /* Explicitly bound the value for the verifier */ + sig_size = sign_result & 0x3F; /* Max 64 bytes */ + + bpf_dynptr_from_mem(algo_p256, sizeof(algo_p256) - 1, 0, &algo_ptr); + bpf_dynptr_from_mem(pubkey_p256, sizeof(pubkey_p256), 0, &pubkey_ptr); + + verify_ctx = bpf_ecdsa_ctx_create(&algo_ptr, &pubkey_ptr, &err); + if (!verify_ctx) { + sign_verify_result = err; + return 0; + } + + bpf_dynptr_from_mem(message_hash, sizeof(message_hash), 0, &msg_ptr); + bpf_dynptr_from_mem(generated_signature, sig_size, 0, &sig_ptr); + + sign_verify_result = bpf_ecdsa_verify(verify_ctx, &msg_ptr, &sig_ptr); + + bpf_ecdsa_ctx_release(verify_ctx); + } + + return 0; +} + +SEC("syscall") +int test_ecdsa_size_queries(void *ctx) +{ + struct bpf_ecdsa_ctx *ecdsa_ctx; + struct bpf_dynptr algo_ptr, key_ptr; + int err = 0; + + bpf_dynptr_from_mem(algo_p256, sizeof(algo_p256) - 1, 0, &algo_ptr); + bpf_dynptr_from_mem(pubkey_p256, sizeof(pubkey_p256), 0, &key_ptr); + + ecdsa_ctx = bpf_ecdsa_ctx_create(&algo_ptr, &key_ptr, &err); + if (!ecdsa_ctx) + return 0; + + keysize_result = bpf_ecdsa_keysize(ecdsa_ctx); + digestsize_result = bpf_ecdsa_digestsize(ecdsa_ctx); + maxsize_result = bpf_ecdsa_maxsize(ecdsa_ctx); + + bpf_ecdsa_ctx_release(ecdsa_ctx); + + return 0; +} + +char __license[] SEC("license") = "GPL";