package/utils/uencrypt/src/uencrypt-openssl.c

   1 /* SPDX-License-Identifier: GPL-2.0-or-later
   2  * Copyright (C) 2022-2023 Eneas Ulir de Queiroz
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <string.h>
   8 #include <unistd.h>
   9 #include "uencrypt.h"
  10
  11 const cipher_t *get_default_cipher(void)
  12 {
  13     return EVP_aes_128_cbc();
  14 }
  15
  16 #ifndef USE_WOLFSSL
  17 static void print_ciphers(const OBJ_NAME *name,void *arg) {
  18     fprintf(arg, "\t%s\n", name->name);
  19 }
  20 #endif
  21
  22 const cipher_t *get_cipher_or_print_error(char *name)
  23 {
  24     const EVP_CIPHER *cipher;
  25
  26     if ((cipher = EVP_get_cipherbyname(name)))
  27         return cipher;
  28
  29     fprintf(stderr, "Error: invalid cipher: %s.\n", name);
  30 #ifndef USE_WOLFSSL
  31     fprintf(stderr, "Supported ciphers: \n");
  32     OBJ_NAME_do_all_sorted(OBJ_NAME_TYPE_CIPHER_METH, print_ciphers, stderr);
  33 #endif
  34     return NULL;
  35 }
  36
  37 int get_cipher_ivsize(const cipher_t *cipher)
  38 {
  39     return EVP_CIPHER_iv_length(cipher);
  40 }
  41
  42 int get_cipher_keysize(const cipher_t *cipher)
  43 {
  44     return EVP_CIPHER_key_length(cipher);
  45 }
  46
  47 ctx_t *create_ctx(const cipher_t *cipher, const unsigned char *key,
  48                   const unsigned char *iv, int enc, int padding)
  49 {
  50     EVP_CIPHER_CTX *ctx;
  51     int ret;
  52
  53     ctx = EVP_CIPHER_CTX_new();
  54     if (!ctx) {
  55         fprintf (stderr, "Error: create_ctx: out of memory.\n");
  56         return NULL;
  57     }
  58     ret = EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, enc);
  59     if (!ret) {
  60         fprintf(stderr, "Error:EVP_CipherInit_ex: %d\n", ret);
  61         goto abort;
  62     }
  63     ret = EVP_CIPHER_CTX_set_padding(ctx, padding);
  64     if (!ret) {
  65         fprintf(stderr, "Error:EVP_CIPHER_CTX_set_padding: %d\n", ret);
  66         goto abort;
  67     }
  68
  69     return ctx;
  70
  71 abort:
  72     free_ctx(ctx);
  73     return NULL;
  74 }
  75
  76
  77 int do_crypt(FILE *infile, FILE *outfile, ctx_t *ctx)
  78 {
  79     unsigned char inbuf[CRYPT_BUF_SIZE];
  80     unsigned char outbuf[CRYPT_BUF_SIZE + EVP_MAX_BLOCK_LENGTH];
  81     int inlen, outlen;
  82     int ret;
  83
  84     for (;;) {
  85         inlen = fread(inbuf, 1, CRYPT_BUF_SIZE, infile);
  86         if (inlen <= 0)
  87             break;
  88         ret = EVP_CipherUpdate(ctx, outbuf, &outlen, inbuf, inlen);
  89         if (!ret) {
  90             fprintf(stderr, "Error: EVP_CipherUpdate: %d\n", ret);
  91             return ret;
  92         }
  93         ret = fwrite(outbuf, 1, outlen, outfile);
  94         if (ret != outlen) {
  95             fprintf(stderr, "Error: CipherUpdate short write.\n");
  96             return ret - outlen;
  97         }
  98     }
  99     ret = EVP_CipherFinal_ex(ctx, outbuf, &outlen);
 100     if (!ret) {
 101         fprintf(stderr, "Error: EVP_CipherFinal: %d\n", ret);
 102         return ret;
 103     }
 104     ret = fwrite(outbuf, 1, outlen, outfile);
 105     if (ret != outlen) {
 106         fprintf(stderr, "Error: CipherFinal short write.\n");
 107         return ret - outlen;
 108     }
 109
 110     return 0;
 111 }
 112
 113 void free_ctx(ctx_t *ctx)
 114 {
 115     EVP_CIPHER_CTX_free(ctx);
 116 }