// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)

/*

 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>

 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>

 * Copyright (C) 2015 Huawei Inc.

 * Copyright (C) 2017 Nicira, Inc.

 */

#undef _GNU_SOURCE

#include <stdio.h>

#include <string.h>

#include <errno.h>

#include <inttypes.h>

#include <linux/kernel.h>

#include "libbpf.h"

#include "libbpf_internal.h"

#ifndef ENOTSUPP

#define ENOTSUPP  524

#endif

/* make sure libbpf doesn't use kernel-only integer typedefs */

#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64

#define ERRNO_OFFSET(e)   ((e) - __LIBBPF_ERRNO__START)

#define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c)

#define NR_ERRNO  (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START)

static const char *libbpf_strerror_table[NR_ERRNO] = {

  [ERRCODE_OFFSET(LIBELF)]  = "Something wrong in libelf",

  [ERRCODE_OFFSET(FORMAT)]  = "BPF object format invalid",

  [ERRCODE_OFFSET(KVERSION)]  = "'version' section incorrect or lost",

  [ERRCODE_OFFSET(ENDIAN)]  = "Endian mismatch",

  [ERRCODE_OFFSET(INTERNAL)]  = "Internal error in libbpf",

  [ERRCODE_OFFSET(RELOC)]   = "Relocation failed",

  [ERRCODE_OFFSET(VERIFY)]  = "Kernel verifier blocks program loading",

  [ERRCODE_OFFSET(PROG2BIG)]  = "Program too big",

  [ERRCODE_OFFSET(KVER)]    = "Incorrect kernel version",

  [ERRCODE_OFFSET(PROGTYPE)]  = "Kernel doesn't support this program type",

  [ERRCODE_OFFSET(WRNGPID)] = "Wrong pid in netlink message",

  [ERRCODE_OFFSET(INVSEQ)]  = "Invalid netlink sequence",

  [ERRCODE_OFFSET(NLPARSE)] = "Incorrect netlink message parsing",

};

int libbpf_strerror(int err, char *buf, size_t size)

{

  int ret;

  if (!buf || !size)

    return libbpf_err(-EINVAL);

  err = err > 0 ? err : -err;

  if (err < __LIBBPF_ERRNO__START) {

    ret = strerror_r(err, buf, size);

    buf[size - 1] = '\0';

    return libbpf_err_errno(ret);

  }

  if (err < __LIBBPF_ERRNO__END) {

    const char *msg;

    msg = libbpf_strerror_table[ERRNO_OFFSET(err)];

    ret = snprintf(buf, size, "%s", msg);

    buf[size - 1] = '\0';

    /* The length of the buf and msg is positive.

     * A negative number may be returned only when the

     * size exceeds INT_MAX. Not likely to appear.

     */

    if (ret >= size)

      return libbpf_err(-ERANGE);

    return 0;

  }

  ret = snprintf(buf, size, "Unknown libbpf error %d", err);

  buf[size - 1] = '\0';

  if (ret >= size)

    return libbpf_err(-ERANGE);

  return libbpf_err(-ENOENT);

}

const char *libbpf_errstr(int err)

{

  static __thread char buf[12];

  if (err > 0)

    err = -err;

  switch (err) {

  case -E2BIG:    return "-E2BIG";

  case -EACCES:   return "-EACCES";

  case -EADDRINUSE: return "-EADDRINUSE";

  case -EADDRNOTAVAIL:  return "-EADDRNOTAVAIL";

  case -EAGAIN:   return "-EAGAIN";

  case -EALREADY:   return "-EALREADY";

  case -EBADF:    return "-EBADF";

  case -EBADFD:   return "-EBADFD";

  case -EBUSY:    return "-EBUSY";

  case -ECANCELED:  return "-ECANCELED";

  case -ECHILD:   return "-ECHILD";

  case -EDEADLK:    return "-EDEADLK";

  case -EDOM:   return "-EDOM";

  case -EEXIST:   return "-EEXIST";

  case -EFAULT:   return "-EFAULT";

  case -EFBIG:    return "-EFBIG";

  case -EILSEQ:   return "-EILSEQ";

  case -EINPROGRESS:  return "-EINPROGRESS";

  case -EINTR:    return "-EINTR";

  case -EINVAL:   return "-EINVAL";

  case -EIO:    return "-EIO";

  case -EISDIR:   return "-EISDIR";

  case -ELOOP:    return "-ELOOP";

  case -EMFILE:   return "-EMFILE";

  case -EMLINK:   return "-EMLINK";

  case -EMSGSIZE:   return "-EMSGSIZE";

  case -ENAMETOOLONG: return "-ENAMETOOLONG";

  case -ENFILE:   return "-ENFILE";

  case -ENODATA:    return "-ENODATA";

  case -ENODEV:   return "-ENODEV";

  case -ENOENT:   return "-ENOENT";

  case -ENOEXEC:    return "-ENOEXEC";

  case -ENOLINK:    return "-ENOLINK";

  case -ENOMEM:   return "-ENOMEM";

  case -ENOSPC:   return "-ENOSPC";

  case -ENOTBLK:    return "-ENOTBLK";

  case -ENOTDIR:    return "-ENOTDIR";

  case -ENOTSUPP:   return "-ENOTSUPP";

  case -ENOTTY:   return "-ENOTTY";

  case -ENXIO:    return "-ENXIO";

  case -EOPNOTSUPP: return "-EOPNOTSUPP";

  case -EOVERFLOW:  return "-EOVERFLOW";

  case -EPERM:    return "-EPERM";

  case -EPIPE:    return "-EPIPE";

  case -EPROTO:   return "-EPROTO";

  case -EPROTONOSUPPORT:  return "-EPROTONOSUPPORT";

  case -ERANGE:   return "-ERANGE";

  case -EROFS:    return "-EROFS";

  case -ESPIPE:   return "-ESPIPE";

  case -ESRCH:    return "-ESRCH";

  case -ETXTBSY:    return "-ETXTBSY";

  case -EUCLEAN:    return "-EUCLEAN";

  case -EXDEV:    return "-EXDEV";

  default:

    snprintf(buf, sizeof(buf), "%d", err);

    return buf;

  }

}

static inline __u32 get_unaligned_be32(const void *p)

{

  __be32 val;

  memcpy(&val, p, sizeof(val));

  return be32_to_cpu(val);

}

static inline void put_unaligned_be32(__u32 val, void *p)

{

  __be32 be_val = cpu_to_be32(val);

  memcpy(p, &be_val, sizeof(be_val));

}

#define SHA256_BLOCK_LENGTH 64

#define Ch(x, y, z) (((x) & (y)) ^ (~(x) & (z)))

#define Maj(x, y, z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))

#define Sigma_0(x) (ror32((x), 2) ^ ror32((x), 13) ^ ror32((x), 22))

#define Sigma_1(x) (ror32((x), 6) ^ ror32((x), 11) ^ ror32((x), 25))

#define sigma_0(x) (ror32((x), 7) ^ ror32((x), 18) ^ ((x) >> 3))

#define sigma_1(x) (ror32((x), 17) ^ ror32((x), 19) ^ ((x) >> 10))

static const __u32 sha256_K[64] = {

  0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1,

  0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,

  0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786,

  0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,

  0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147,

  0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,

  0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b,

  0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,

  0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a,

  0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,

  0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,

};

#define SHA256_ROUND(i, a, b, c, d, e, f, g, h)                                \

  {                                                                      \

    __u32 tmp = h + Sigma_1(e) + Ch(e, f, g) + sha256_K[i] + w[i]; \

    d += tmp;                                                      \

    h = tmp + Sigma_0(a) + Maj(a, b, c);                           \

  }

static void sha256_blocks(__u32 state[8], const __u8 *data, size_t nblocks)

{

  while (nblocks--) {

    __u32 a = state[0];

    __u32 b = state[1];

    __u32 c = state[2];

    __u32 d = state[3];

    __u32 e = state[4];

    __u32 f = state[5];

    __u32 g = state[6];

    __u32 h = state[7];

    __u32 w[64];

    int i;

    for (i = 0; i < 16; i++)

      w[i] = get_unaligned_be32(&data[4 * i]);

    for (; i < ARRAY_SIZE(w); i++)

      w[i] = sigma_1(w[i - 2]) + w[i - 7] +

             sigma_0(w[i - 15]) + w[i - 16];

    for (i = 0; i < ARRAY_SIZE(w); i += 8) {

      SHA256_ROUND(i + 0, a, b, c, d, e, f, g, h);

      SHA256_ROUND(i + 1, h, a, b, c, d, e, f, g);

      SHA256_ROUND(i + 2, g, h, a, b, c, d, e, f);

      SHA256_ROUND(i + 3, f, g, h, a, b, c, d, e);

      SHA256_ROUND(i + 4, e, f, g, h, a, b, c, d);

      SHA256_ROUND(i + 5, d, e, f, g, h, a, b, c);

      SHA256_ROUND(i + 6, c, d, e, f, g, h, a, b);

      SHA256_ROUND(i + 7, b, c, d, e, f, g, h, a);

    }

    state[0] += a;

    state[1] += b;

    state[2] += c;

    state[3] += d;

    state[4] += e;

    state[5] += f;

    state[6] += g;

    state[7] += h;

    data += SHA256_BLOCK_LENGTH;

  }

}

void libbpf_sha256(const void *data, size_t len, __u8 out[SHA256_DIGEST_LENGTH])

{

  __u32 state[8] = { 0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,

         0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19 };

  const __be64 bitcount = cpu_to_be64((__u64)len * 8);

  __u8 final_data[2 * SHA256_BLOCK_LENGTH] = { 0 };

  size_t final_len = len % SHA256_BLOCK_LENGTH;

  int i;

  sha256_blocks(state, data, len / SHA256_BLOCK_LENGTH);

  memcpy(final_data, data + len - final_len, final_len);

  final_data[final_len] = 0x80;

  final_len = roundup(final_len + 9, SHA256_BLOCK_LENGTH);

  memcpy(&final_data[final_len - 8], &bitcount, 8);

  sha256_blocks(state, final_data, final_len / SHA256_BLOCK_LENGTH);

  for (i = 0; i < ARRAY_SIZE(state); i++)

    put_unaligned_be32(state[i], &out[4 * i]);

}