summaryrefslogtreecommitdiff
path: root/src/main.c
blob: 91ec457290e23430fb0ba175b1e7f008e1dc8a44 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
/*
 * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora team.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of Osmora nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
#include <assert.h>
#include <unistd.h>
#include <info.h>
#if defined(__x86_64__)
#include <accel.h>
#endif  /* defined(__x86_64__) */

#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__
#error "Big endian machines not supported yet"
#endif

#if defined(__x86_64__)
#define cpuid(level, a, b, c, d)					\
  __asm__ __volatile__ ("cpuid\n\t"					\
			: "=a" (a), "=b" (b), "=c" (c), "=d" (d)	\
			: "0" (level))
#endif

#define flip_block(TMP_VAR, TYPE, BUF, POS)         \
        TMP_VAR = *(TYPE *)&BUF[POS];               \
        TMP_VAR = ~TMP_VAR;                         \
        *(TYPE *)&BUF[POS] = TMP_VAR;               \

static char *
read_file(const char *fname, size_t *size_out)
{
    FILE *fp;
    char *buf;
    size_t bufsize;

    if (access(fname, F_OK) != 0) {
        fprintf(stderr, "%s does not exist!\n", fname);
        return NULL;
    }

    fp = fopen(fname, "r");

    /* Get file size */
    fseek(fp, 0, SEEK_END);
    bufsize = ftell(fp);
    fseek(fp, 0, SEEK_SET);

    buf = malloc(bufsize);
    fread(buf, sizeof(char), bufsize, fp);
    fclose(fp);

    *size_out = bufsize;

    return buf;
}

static void
writeback_file(const char *fname, const char *buf, size_t buf_size)
{
    FILE *fp;

    fp = fopen(fname, "w");
    fwrite(buf, buf_size, sizeof(char), fp);
    fclose(fp);
}

#if defined(__x86_64__)
static inline bool
is_sse3_supported(void)
{
    uint32_t ecx, unused;

    cpuid(0x0000001, unused, unused, ecx, unused);
    return (ecx & (1 << 0)) != 0;
}

static inline bool
is_sse2_supported(void)
{
    uint32_t edx, unused;
    cpuid(0x0000001, unused, unused, unused, edx);
    return (edx & (1 << 26)) != 0;
}

static inline bool
is_avx_supported(void)
{
    uint32_t ecx, unused;
    cpuid(0x0000001, unused, unused, ecx, unused);
    return (ecx & (1 << 28)) != 0;
}

static void
amd64_cpu_tests(struct cpu_info *info)
{
    bool sse3_supported;

    sse3_supported = false;

    if (is_sse3_supported()) {
        printf("[?]: SSE3 supported, may use as optimization\n");
        sse3_supported = true;
        info->has_sse3 = 1;
    }

    if (!sse3_supported) {
        if (is_sse2_supported()) {
            printf("[?]: SSE2 supported, may use as optimization\n");
            info->has_sse2 = 1;
        }
    }

    if (is_avx_supported()) {
        printf("[?]: AVX supported, may use as optimization\n");
        info->has_avx = 1;
    }
}
#endif  /* defined(__x86_64__) */

static char *
encrypt(const struct cpu_info *info, char *buf, size_t buf_size)
{
    size_t current_pos;
    size_t step;
    uint64_t tmp;

    current_pos = 0;
    step = 8;           /* Start at 8 bytes (64 bits) */

#if defined(__x86_64__)
    if (info->has_sse2 || info->has_sse3) {
        step = 16;         /* Start at 16 bytes (128 bits) */
    }
    if (info->has_avx) {
        step = 32;
    }
#endif  /* defined(__x86_64__) */

    while (current_pos < buf_size) {
        /* Ensure we aren't over 16 bytes and a power of two */
        if (step != 1) {
            assert((step & 1) == 0 && step <= 32);
        }

        /* Ensure we don't cause any overflows */
        while (((current_pos + step) >= buf_size) && step > 1)
            /* Essentially divide the step by 2, just faster */
            step >>= 1;

        switch (step) {
        case 32:
            accel_invert256((uintptr_t)buf + current_pos);
            break;
        case 16:
            accel_invert128((uintptr_t)buf + current_pos);
            break;
        case 8:
            flip_block(tmp, uint64_t, buf, current_pos);
            break;
        case 4:
            flip_block(tmp, uint32_t, buf, current_pos);
            break;
        case 2:
            flip_block(tmp, uint16_t, buf, current_pos);
            break;
        case 1:
            flip_block(tmp, uint8_t, buf, current_pos);
            break;
        }

        current_pos += step;
    }
}

int
main(int argc, const char **argv)
{
    size_t buf_size;
    char *buf;
    struct cpu_info info = { 0 };

    if (argc < 2) {
        fprintf(stderr, "Usage: %s <file>\n", argv[0]);
        return 1;
    }

#if defined(__x86_64__)
    amd64_cpu_tests(&info);
#endif  /* __x86_64__ */

    buf = read_file(argv[1], &buf_size);
    if (buf == NULL) {
        return 1;
    }

    encrypt(&info, buf, buf_size);
    writeback_file(argv[1], buf, buf_size);
    free(buf);

    return 0;
}