ucert.c

   1 /*
   2  * Copyright (C) 2018 Daniel Golle <daniel@makrotopia.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 3
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #define _GNU_SOURCE
  15
  16 #include <fcntl.h>
  17 #include <dlfcn.h>
  18 #include <stdio.h>
  19 #include <stdbool.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <getopt.h>
  23 #include <stdint.h>
  24 #include <unistd.h>
  25 #include <inttypes.h>
  26 #include <sys/stat.h>
  27 #include <sys/wait.h>
  28
  29 #include <json-c/json.h>
  30 #include <libubox/blob.h>
  31 #include <libubox/utils.h>
  32 #include <libubox/list.h>
  33 #include <libubox/vlist.h>
  34 #include <libubox/blobmsg_json.h>
  35
  36 #define CERT_BUF_LEN 4096
  37
  38 static enum {
  39         CMD_APPEND,
  40         CMD_DUMP,
  41         CMD_ISSUE,
  42         CMD_REVOKE,
  43         CMD_VERIFY,
  44         CMD_NONE,
  45 } cmd = CMD_NONE;
  46
  47 static bool quiet;
  48
  49 enum cert_attr {
  50         CERT_ATTR_SIGNATURE,
  51         CERT_ATTR_PAYLOAD,
  52         CERT_ATTR_MAX
  53 };
  54
  55 static const struct blob_attr_info cert_policy[CERT_ATTR_MAX] = {
  56         [CERT_ATTR_SIGNATURE] = { .type = BLOB_ATTR_BINARY },
  57         [CERT_ATTR_PAYLOAD] = { .type = BLOB_ATTR_NESTED },
  58 };
  59
  60 enum cert_payload_attr {
  61         CERT_PL_ATTR_CERTTYPE,
  62         CERT_PL_ATTR_CERTID,
  63         CERT_PL_ATTR_VALIDFROMTIME,
  64         CERT_PL_ATTR_EXPIRETIME,
  65         CERT_PL_ATTR_PUBKEY,
  66         CERT_PL_ATTR_KEY_FINGERPRINT,
  67         CERT_PL_ATTR_MAX
  68 };
  69
  70 enum certtype_id {
  71         CERTTYPE_UNSPEC,
  72         CERTTYPE_AUTH,
  73         CERTTYPE_REVOKE
  74 };
  75
  76 static const struct blobmsg_policy cert_payload_policy[CERT_PL_ATTR_MAX] = {
  77         [CERT_PL_ATTR_CERTTYPE] = { .type = BLOBMSG_TYPE_INT8 },
  78         [CERT_PL_ATTR_CERTID] = { .type = BLOBMSG_TYPE_INT64 },
  79         [CERT_PL_ATTR_VALIDFROMTIME] = { .type = BLOBMSG_TYPE_INT64 },
  80         [CERT_PL_ATTR_EXPIRETIME] = { .type = BLOBMSG_TYPE_INT64 },
  81         [CERT_PL_ATTR_PUBKEY] = { .type = BLOBMSG_TYPE_STRING },
  82         [CERT_PL_ATTR_KEY_FINGERPRINT] = { .type = BLOBMSG_TYPE_STRING },
  83 };
  84
  85
  86 static int cert_load(const char *certfile, struct blob_attr *certtb[]) {
  87         FILE *f;
  88         struct blob_buf certbuf;
  89         int ret = 0;
  90         char filebuf[CERT_BUF_LEN];
  91         int len;
  92
  93         blob_buf_init(&certbuf, 0);
  94
  95         f = fopen(certfile, "r");
  96         if (!f)
  97                 return 1;
  98
  99         do {
 100                 len = fread(&filebuf, 1, CERT_BUF_LEN - 1, f);
 101                 blob_put_raw(&certbuf, filebuf, len);
 102         } while(!feof(f) && !ferror(f));
 103
 104         ret = ferror(f);
 105         fclose(f);
 106
 107         if (ret)
 108                 return 1;
 109
 110         blob_parse(certbuf.head, certtb, cert_policy, CERT_ATTR_MAX);
 111
 112         return 0;
 113 }
 114
 115 static int cert_append(const char *certfile, const char *pubkeyfile, const char *sigfile) {
 116         fprintf(stderr, "not implemented\n");
 117         return 1;
 118 }
 119
 120 static int cert_dump(const char *certfile) {
 121         struct blob_attr *certtb[CERT_ATTR_MAX];
 122
 123         if (cert_load(certfile, certtb)) {
 124                 fprintf(stderr, "cannot parse cert\n");
 125                 return 1;
 126         }
 127
 128         return 0;
 129 }
 130
 131 static int cert_issue(const char *certfile, const char *pubkeyfile, const char *seckeyfile) {
 132         fprintf(stderr, "not implemented\n");
 133         return 1;
 134 }
 135
 136 static int cert_process_revoker(const char *certfile) {
 137         fprintf(stderr, "not implemented\n");
 138         return 1;
 139 }
 140
 141 static int cert_verify(const char *certfile, const char *pubkeyfile, const char *pubkeydir, const char *msgfile) {
 142         fprintf(stderr, "not implemented\n");
 143         return 1;
 144 }
 145
 146 static int usage(const char *cmd)
 147 {
 148         fprintf(stderr,
 149                 "Usage: %s <command> <options>\n"
 150                 "Commands:\n"
 151                 "  -A:                  append (needs -c and -p and/or -x)\n"
 152                 "  -D:                  dump\n"
 153                 "  -I:                  issue cert and revoker (needs -c and -p and -s)\n"
 154                 "  -R:                  process revoker certificate (needs -c)\n"
 155                 "  -V:                  verify (needs -c and -p|-P)\n"
 156                 "Options:\n"
 157                 "  -c <file>:           certificate file\n"
 158                 "  -m <file>:           message file (verify only)\n"
 159                 "  -p <file>:           public key file\n"
 160                 "  -P <path>:           public key directory (verify only)\n"
 161                 "  -q:                  quiet (do not print verification result, use return code only)\n"
 162                 "  -s <file>:           secret key file (issue only)\n"
 163                 "  -x <file>:           signature file\n"
 164                 "\n",
 165                 cmd);
 166         return 1;
 167 }
 168
 169 int main(int argc, char *argv[]) {
 170         int ch;
 171         const char *msgfile = NULL;
 172         const char *sigfile = NULL;
 173         const char *pubkeyfile = NULL;
 174         const char *pubkeydir = NULL;
 175         const char *certfile = NULL;
 176         const char *seckeyfile = NULL;
 177
 178         quiet = false;
 179         while ((ch = getopt(argc, argv, "ADIRVc:m:p:P:qs:x:")) != -1) {
 180                 switch (ch) {
 181                 case 'A':
 182                         cmd = CMD_APPEND;
 183                         break;
 184                 case 'D':
 185                         cmd = CMD_DUMP;
 186                         break;
 187                 case 'I':
 188                         cmd = CMD_ISSUE;
 189                         break;
 190                 case 'R':
 191                         cmd = CMD_REVOKE;
 192                         break;
 193                 case 'V':
 194                         cmd = CMD_VERIFY;
 195                         break;
 196                 case 'c':
 197                         certfile = optarg;
 198                         break;
 199                 case 'm':
 200                         msgfile = optarg;
 201                         break;
 202                 case 'p':
 203                         pubkeyfile = optarg;
 204                         break;
 205                 case 'P':
 206                         pubkeydir = optarg;
 207                         break;
 208                 case 's':
 209                         seckeyfile = optarg;
 210                         break;
 211                 case 'q':
 212                         quiet = true;
 213                         break;
 214                 case 'x':
 215                         sigfile = optarg;
 216                         break;
 217                 default:
 218                         return usage(argv[0]);
 219                 }
 220         }
 221
 222         switch (cmd) {
 223         case CMD_APPEND:
 224                 if (certfile && (pubkeyfile || sigfile))
 225                         return cert_append(certfile, pubkeyfile, sigfile);
 226                 else
 227                         return usage(argv[0]);
 228         case CMD_DUMP:
 229                 if (certfile)
 230                         return cert_dump(certfile);
 231                 else
 232                         return usage(argv[0]);
 233         case CMD_ISSUE:
 234                 if (certfile && pubkeyfile && seckeyfile)
 235                         return cert_issue(certfile, pubkeyfile, seckeyfile);
 236                 else
 237                         return usage(argv[0]);
 238         case CMD_REVOKE:
 239                 if (certfile)
 240                         return cert_process_revoker(certfile);
 241                 else
 242                         return usage(argv[0]);
 243         case CMD_VERIFY:
 244                 if (certfile && (pubkeyfile || pubkeydir))
 245                         return cert_verify(certfile, pubkeyfile, pubkeydir, msgfile);
 246                 else
 247                         return usage(argv[0]);
 248         case CMD_NONE:
 249                 return usage(argv[0]);
 250         }
 251
 252         /* unreachable */
 253         return usage(argv[0]);
 254 }