/*      $OpenBSD: base64test.c,v 1.10 2022/09/05 21:06:31 tb Exp $      */
/*
 * Copyright (c) 2014 Joel Sing <jsing@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <openssl/bio.h>
#include <openssl/evp.h>

#include <err.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>

#define BUF_SIZE 128

struct base64_test {
        const unsigned char in[BUF_SIZE];
        const ssize_t in_len;
        const unsigned char out[BUF_SIZE];
        const ssize_t out_len;
        const ssize_t valid_len;
};

/*
 * Many of these tests are based on those found in Go's encoding/base64 tests.
 */
struct base64_test base64_tests[] = {

        /* RFC3548 examples. */
        { "\x14\xfb\x9c\x03\xd9\x7e", 6, "FPucA9l+", 8, 6, },
        { "\x14\xfb\x9c\x03\xd9", 5, "FPucA9k=", 8, 5, },
        { "\x14\xfb\x9c\x03", 4, "FPucAw==", 8, 4, },

        /* RFC4648 examples. */
        { "", 0, "", 0, 0, },
        { "f", 1, "Zg==", 4, 1, },
        { "fo", 2, "Zm8=", 4, 2, },
        { "foo", 3, "Zm9v", 4, 3, },
        { "foob", 4, "Zm9vYg==", 8, 4, },
        { "fooba", 5, "Zm9vYmE=", 8, 5, },
        { "foobar", 6, "Zm9vYmFy", 8, 6, },

        /* Wikipedia examples. */
        { "sure.", 5, "c3VyZS4=", 8, 5, },
        { "sure", 4, "c3VyZQ==", 8, 4, },
        { "sur", 3, "c3Vy", 4, 3, },
        { "su", 2, "c3U=", 4, 2, },
        { "leasure.", 8, "bGVhc3VyZS4=", 12, 8, },
        { "easure.", 7, "ZWFzdXJlLg==", 12, 7, },
        { "asure.", 6, "YXN1cmUu", 8, 6, },

        { "abcd", 4, "YWJjZA==", 8, 4, },

        {
                "Twas brillig, and the slithy toves",
                34,
                "VHdhcyBicmlsbGlnLCBhbmQgdGhlIHNsaXRoeSB0b3Zlcw==",
                48,
                34,
        },
};

#define N_TESTS (sizeof(base64_tests) / sizeof(*base64_tests))

struct base64_test base64_nl_tests[] = {

        /* Corrupt/invalid encodings. */
        { "", -1, "", 0, 0, },
        { "", -1, "!!!!", 4, 0, },
        { "", -1, "====", 4, 0, },
        { "", -1, "x===", 4, 0, },
        { "", -1, "=AAA", 4, 0, },
        { "", -1, "A=AA", 4, 0, },
        { "", -1, "AA=A", 4, 0, },
        { "", -1, "AA==A", 5, 0, },
        { "", -1, "AAA=AAAA", 8, 0, },
        { "", -1, "AAAAA", 5, 0, },
        { "", -1, "AAAAAA", 6, 0, },
        { "", -1, "A=", 2, 0, },
        { "", -1, "A==", 3, 0, },
        { "", -1, "AA=", 3, 0, },
        { "", -1, "AA==", 4, 1, },              /* XXX - output ix 0x0. */
        { "", -1, "AAA=", 4, 2, },              /* XXX - output ix 2x 0x0. */
        { "", -1, "AAAA", 4, 3, },              /* XXX - output ix 3x 0x0. */
        { "", -1, "AAAAAA=", 7, 0, },
        { "", -1, "YWJjZA=====", 11, 0, },


        /* Encodings with embedded CR/LF. */
        { "sure", 4, "c3VyZQ==", 8, 4, },
        { "sure", 4, "c3VyZQ==\r", 9, 4, },
        { "sure", 4, "c3VyZQ==\n", 9, 4, },
        { "sure", 4, "c3VyZQ==\r\n", 10, 4, },
        { "sure", 4, "c3VyZ\r\nQ==", 10, 4, },
        { "sure", 4, "c3V\ryZ\nQ==", 10, 4, },
        { "sure", 4, "c3V\nyZ\rQ==", 10, 4, },
        { "sure", 4, "c3VyZ\nQ==", 9, 4, },
        { "sure", 4, "c3VyZQ\n==", 9, 4, },
        { "sure", 4, "c3VyZQ=\n=", 9, 4, },
        { "sure", 4, "c3VyZQ=\r\n\r\n=", 12, 4, },

        {
                "",
                -1,
                "YWJjZA======================================================"
                "============",
                74,
                0,
        },

        /* OpenSSL-1.1.1d test */
        /* canonical */
        { "", 0, "", 0, 0, },
        /* canonical */
        { "h", 1, "aA==\n", 5, 1, },
        /* canonical */
        { "hello", 5, "aGVsbG8=\n", 9, 5, },
        /* canonical */
        { "hello world!", 12, "aGVsbG8gd29ybGQh\n", 17, 12, },
        /* canonical */
        { "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\xa0\xb0\xc0\xd0\xe0\xf0\x00", 17, "AAECAwQFBgcICaCwwNDg8AA=\n", 25, 17, },
        /* invalid # Missing padding */
        { "", -1, "aGVsbG8", 7, 0, },
        /* invalid */
        { "", -1, "aGVsbG8\n", 8, 0, },
        /* valid # Tolerate missing newline */
        { "hello", -1, "aGVsbG8=", 8, 5, },
        /* invalid # Don't tolerate extra trailing '=' */
        { "", -1, "aGVsbG8==\n", 10, 0, },
        /* invalid */
        { "", -1, "aGVsbG8===\n", 11, 0, },
        /* invalid # Don't tolerate data after '=' */
        { "", -1, "aGV=sbG8=\n", 10, 0, },
        /* valid # Newlines are ignored */
        { "hello", -1, "aGV\nsbG8=\n", 10, 5, },
        /* canonical */
        { "hello", 5, "\x61\x47\x56\x73\x62\x47\x38\x3d\x0a", 9, 5, },
        /* invalid # Invalid characters */
        { "", -1, "\x61\x47\x56\x73\x62\x47\x38\x3d\x0a\x00", 10, 0, },
        /* invalid */
        { "", -1, "\x61\x47\x56\x00\x73\x62\x47\x38\x3d\x0a", 10, 0, },
        /* invalid */
        { "", -1, "\x61\x47\x56\x01\x73\x62\x47\x38\x3d\x0a", 10, 0, },
        /* invalid */
        { "", -1, "\x61\x47\x56\x80\x73\x62\x47\x38\x3d\x0a", 10, 0, },
        /* invalid */
        { "", -1, "\xe1\x47\x56\x73\x62\x47\x38\x3d\x0a", 9, 0, },
        /* canonical */
        { "OpenSSLOpenSSL\n", 15, "T3BlblNTTE9wZW5TU0wK\n", 21, 15, },
        /* valid */
        { "OpenSSLOpenSSL\n", -1, "T3BlblNTTE9wZW5TU0wK", 20, 15, },
        /* invalid # Truncate 1-3 chars */
        { "", -1, "T3BlblNTTE9wZW5TU0w", 19, 0, },
        /* invalid */
        { "", -1, "T3BlblNTTE9wZW5TU0", 18, 0, },
        /* invalid */
        { "", -1, "T3BlblNTTE9wZW5TU", 17, 0, },
        /* invalid */
        { "", -1, "T3BlblNTTE9wZW5TU0wK====", 24, 0, },
        /* invalid */
        { "", -1, "T3BlblNTTE9wZW5TU0wK============================================\n", 65, 0, },
        /* invalid */
        { "", -1, "YQ==YQ==YQ==\n", 13, 0, },
        /* invalid */
        { "", -1, "A", 1, 0, },
        /* invalid */
        { "", -1, "A\n", 2, 0, },
        /* invalid */
        { "", -1, "A=", 2, 0, },
        /* invalid */
        { "", -1, "A==\n", 4, 0, },
        /* invalid */
        { "", -1, "A===\n", 5, 0, },
        /* invalid */
        { "", -1, "A====\n", 6, 0, },
        /* valid */
        { "OpenSSLOpenSSL\n", -1, "T3BlblNTTE9wZW5TU0wK\n\n", 22, 15, },
        /* valid */
        { "OpenSSLOpenSSL\n", -1, "T3BlblNTTE\n9wZW5TU0wK", 21, 15, },
        /* invalid # CVE 2015-0292 */
        { "", -1, "ZW5jb2RlIG1lCg==================================================================\n", 81, 0, },
        /* canonical */
        { "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", 46, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eA==\n", 65, 46, },
        /* valid */
        { "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", -1, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eA\n==\n", 66, 46, },
        /* valid */
        { "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", -1, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eA=\n=\n", 66, 46, },
        /* invalid */
        { "", -1, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eA====\n", 67, 0, },
        /* canonical # Multiline output without padding */
        { "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", 60, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4\neHh4eHh4eHh4eHh4\n", 82, 60, },
        /* canonical # Multiline output with padding */
        { "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", 64, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4\neHh4eHh4eHh4eHh4eHh4eA==\n", 90, 64, },
        /* valid # Multiline output with line break in the middle of a b64 block is accepted */
        { "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", -1, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh\n4eHh4eHh4eHh4eHh4eHh4eA==\n", 90, 64, },
        /* valid # Long lines are accepted */
        { "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", -1, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eA==\n", 89, 64, },
        /* invalid # Multiline input with data after '='. */
        { "", -1, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eA==\neHh4eHh4eHh4eHh4eHh4eHh4\n", 90, 0, },
        /* invalid */
        { "", -1, "eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4eHh4\neA==eHh4eHh4eHh4eHh4eHh4\n", 90, 0, },
        /* valid # B64_EOF ('-') terminates input and trailing bytes are ignored */
        { "OpenSSLOpenSSL\n", -1, "T3BlblNTTE9wZW5TU0wK\n-abcd", 26, 15, },
        /* valid */
        { "OpenSSLOpenSSL\n", -1, "T3BlblNTTE9wZW5TU0wK-abcd", 25, 15, },
};

#define N_NL_TESTS (sizeof(base64_nl_tests) / sizeof(*base64_nl_tests))

struct base64_test base64_no_nl_tests[] = {

        /*
         * In non-newline mode, the output resulting from corrupt/invalid
         * encodings is completely crazy. A number of zero bytes is returned
         * rather than nothing.
         */

        /* Corrupt/invalid encodings. */
        { "", -1, "", 0, 0, },
        { "", -1, "!!!!", 4, 0, },
        { "", -1, "====", 4, 1, },
        { "", -1, "x===", 4, 1, },
        { "", -1, "=AAA", 4, 3, },
        { "", -1, "A=AA", 4, 3, },
        { "", -1, "AA=A", 4, 3, },
        { "", -1, "AA==A", 5, 1, },
        { "", -1, "AAA=AAAA", 8, 6, },
        { "", -1, "AAAAA", 5, 3, },
        { "", -1, "AAAAAA", 6, 3, },
        { "", -1, "A=", 2, 0, },
        { "", -1, "A==", 3, 0, },
        { "", -1, "AA=", 3, 0, },
        { "", -1, "AA==", 4, 1, },
        { "", -1, "AAA=", 4, 2, },
        { "", -1, "AAAA", 4, 3, },
        { "", -1, "AAAAAA=", 7, 3, },
        { "", -1, "YWJjZA=====", 11, 4, },

        /* Encodings with embedded CR/LF. */
        { "sure", 4, "c3VyZQ==", 8, 4, },
        { "sure", 4, "c3VyZQ==\r", 9, 4, },
        { "sure", 4, "c3VyZQ==\n", 9, 4, },
        { "sure", 4, "c3VyZQ==\r\n", 10, 4, },
        { "sure", -1, "c3VyZ\r\nQ==", 10, 0, },
        { "sure", -1, "c3V\ryZ\nQ==", 10, 0, },
        { "sure", -1, "c3V\nyZ\rQ==", 10, 0, },
        { "sure", -1, "c3VyZ\nQ==", 9, 0, },
        { "sure", -1, "c3VyZQ\n==", 9, 0, },
        { "sure", -1, "c3VyZQ=\n=", 9, 0, },
        { "sure", -1, "c3VyZQ=\r\n\r\n=", 12, 0, },

        /*
         * This is invalid, yet results in 'abcd' followed by a stream of
         * zero value bytes.
         */
        {
                "",
                -1,
                "YWJjZA======================================================"
                "============",
                74,
                52,
        },
};

#define N_NO_NL_TESTS (sizeof(base64_no_nl_tests) / sizeof(*base64_no_nl_tests))

static int
base64_encoding_test(int test_no, struct base64_test *bt, int test_nl)
{
        BIO *bio_b64, *bio_mem;
        unsigned char *buf, *out;
        ssize_t i, len, b64len;
        int failure = 0;

        buf = malloc(BUF_SIZE);
        if (buf == NULL)
                errx(1, "malloc");

        bio_b64 = BIO_new(BIO_f_base64());
        if (bio_b64 == NULL)
                errx(1, "BIO_new failed for BIO_f_base64");

        bio_mem = BIO_new(BIO_s_mem());
        if (bio_mem == NULL)
                errx(1, "BIO_new failed for BIO_s_mem");

        bio_mem = BIO_push(bio_b64, bio_mem);

        if (!test_nl)
                BIO_set_flags(bio_b64, BIO_FLAGS_BASE64_NO_NL);

        len = BIO_write(bio_mem, bt->in, bt->in_len);
        if (len != bt->in_len) {
                fprintf(stderr, "FAIL: test %d - only wrote %zd out of %zd "
                    "characters\n", test_no, len, bt->in_len);
                failure = 1;
                goto done;
        }
        if (BIO_flush(bio_mem) < 0) {
                fprintf(stderr, "FAIL: test %d - flush failed\n", test_no);
                failure = 1;
                goto done;
        }

        b64len = 0;
        for (i = 0; i < bt->out_len; i++) {
                if ((!test_nl ||
                    (test_nl && (i % 64 != 0 || i == bt->out_len - 1))) &&
                    (bt->out[i] == '\r' || bt->out[i] == '\n'))
                        continue;
                buf[b64len++] = bt->out[i];
        }
        if (test_nl)
                buf[b64len++] = '\n';

        len = BIO_get_mem_data(bio_mem, &out);

        /* An empty string with NL results in no output, rather than '\n'. */
        if (test_nl && b64len == 1 && len == 0)
                goto done;

        if (len != b64len) {
                fprintf(stderr, "FAIL: test %d - encoding resulted in %zd "
                    "characters instead of %zd\n", test_no, len, b64len);
                failure = 1;
                goto done;
        }

        if (memcmp(buf, out, b64len) != 0) {
                fprintf(stderr, "FAIL: test %d - encoding differs:\n", test_no);
                fprintf(stderr, "  encoding: ");
                for (i = 0; i < len; i++)
                        fprintf(stderr, "%c", out[i]);
                fprintf(stderr, "\n");
                fprintf(stderr, " test data: ");
                for (i = 0; i < bt->out_len; i++)
                        fprintf(stderr, "%c", buf[i]);
                fprintf(stderr, "\n");
                failure = 1;
        }

done:
        BIO_free_all(bio_mem);
        free(buf);

        return failure;
}

static int
base64_decoding_test(int test_no, struct base64_test *bt, int test_nl)
{
        BIO *bio_b64, *bio_mem;
        char *buf, *input;
        ssize_t i, inlen, len;
        int failure = 0;

        buf = malloc(BUF_SIZE);
        if (buf == NULL)
                errx(1, "malloc");

        if ((input = malloc(BUF_SIZE)) == NULL)
                errx(1, "malloc");

        memcpy(input, bt->out, bt->out_len);
        inlen = bt->out_len;
        if (test_nl) {
                memcpy(&input[bt->out_len], "\r\n", 2);
                inlen += 2;
        }

        bio_mem = BIO_new_mem_buf(input, inlen);
        if (bio_mem == NULL)
                errx(1, "BIO_new_mem_buf failed");

        bio_b64 = BIO_new(BIO_f_base64());
        if (bio_b64 == NULL)
                errx(1, "BIO_new failed for BIO_f_base64");

        if (!test_nl)
                BIO_set_flags(bio_b64, BIO_FLAGS_BASE64_NO_NL);

        bio_mem = BIO_push(bio_b64, bio_mem);

        /*
         * If we wrote zero characters then a BIO_read will result in a return
         * value of -1, hence we need to handle this case.
         */
        len = BIO_read(bio_mem, buf, BUF_SIZE);
        if (len != bt->valid_len && (bt->in_len != 0 || len != -1)) {
                fprintf(stderr, "FAIL: test %d - decoding resulted in %zd "
                    "characters instead of %zd\n", test_no, len, bt->valid_len);
                fprintf(stderr, "  input: ");
                for (i = 0; i < inlen; i++)
                        fprintf(stderr, "%c", input[i]);
                fprintf(stderr, "\n");
                fprintf(stderr, "  decoding: ");
                for (i = 0; i < len; i++)
                        fprintf(stderr, "0x%x ", buf[i]);
                fprintf(stderr, "\n");
                failure = 1;
                goto done;
        }

        /* See if we expect this to fail decoding. */
        if (bt->in_len == -1)
                goto done;

        if (memcmp(bt->in, buf, bt->in_len) != 0) {
                fprintf(stderr, "FAIL: test %d - decoding differs:\n", test_no);
                fprintf(stderr, "  decoding: ");
                for (i = 0; i < len; i++)
                        fprintf(stderr, "0x%x ", buf[i]);
                fprintf(stderr, "\n");
                fprintf(stderr, " test data: ");
                for (i = 0; i < bt->in_len; i++)
                        fprintf(stderr, "0x%x ", bt->in[i]);
                fprintf(stderr, "\n");
                failure = 1;
        }

done:
        BIO_free_all(bio_mem);
        free(buf);
        free(input);

        return failure;
}

int
main(int argc, char **argv)
{
        struct base64_test *bt;
        int failed = 0;
        size_t i;

        fprintf(stderr, "Starting combined tests...\n");

        for (i = 0; i < N_TESTS; i++) {
                bt = &base64_tests[i];
                if (bt->in_len != -1)
                        failed += base64_encoding_test(i, bt, 0);
                if (bt->out_len != -1)
                        failed += base64_decoding_test(i, bt, 0);
                if (bt->in_len != -1)
                        failed += base64_encoding_test(i, bt, 1);
                if (bt->out_len != -1)
                        failed += base64_decoding_test(i, bt, 1);
        }

        fprintf(stderr, "Starting NL tests...\n");

        for (i = 0; i < N_NL_TESTS; i++) {
                bt = &base64_nl_tests[i];

                if (bt->in_len != -1)
                        failed += base64_encoding_test(i, bt, 1);
                if (bt->out_len != -1)
                        failed += base64_decoding_test(i, bt, 1);
        }

        fprintf(stderr, "Starting NO NL tests...\n");

        for (i = 0; i < N_NO_NL_TESTS; i++) {
                bt = &base64_no_nl_tests[i];

                if (bt->in_len != -1)
                        failed += base64_encoding_test(i, bt, 0);
                if (bt->out_len != -1)
                        failed += base64_decoding_test(i, bt, 0);
        }

        return failed;
}