/* $NetBSD: params.c,v 1.29 2016/12/11 00:34:39 alnsn Exp $ */ /*- * Copyright (c) 2002, 2003 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Roland C. Dowdeswell. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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 #ifndef lint __RCSID("$NetBSD: params.c,v 1.29 2016/12/11 00:34:39 alnsn Exp $"); #endif #include #include #include #include #include #include #include #include #include #include "params.h" #include "pkcs5_pbkdf2.h" #include "utils.h" #include "cgdconfig.h" #include "extern.h" static void params_init(struct params *); static void print_kvpair_cstr(FILE *, int, const char *, const char *); static void print_kvpair_string(FILE *, int, const char *, const string_t *); static void print_kvpair_int(FILE *, int, const char *, size_t); static void print_kvpair_b64(FILE *, int, int, const char *, bits_t *); static void spaces(FILE *, int); /* keygen defaults */ #define DEFAULT_SALTLEN 128 #define DEFAULT_ITERATION_TIME 2000000 /* 1 second in microseconds */ /* crypto defaults functions */ static struct crypto_defaults { char alg[32]; int keylen; } crypto_defaults[] = { { "aes-cbc", 128 }, { "aes-xts", 256 }, { "3des-cbc", 192 }, { "blowfish-cbc", 128 } }; static int crypt_defaults_lookup(const char *); struct params * params_new(void) { struct params *p; p = emalloc(sizeof(*p)); params_init(p); return p; } static void params_init(struct params *p) { p->algorithm = NULL; p->ivmeth = NULL; p->key = NULL; p->keylen = (size_t)-1; p->bsize = (size_t)-1; p->verify_method = VERIFY_UNKNOWN; p->dep_keygen = NULL; p->keygen = NULL; } void params_free(struct params *p) { if (!p) return; string_free(p->algorithm); string_free(p->ivmeth); keygen_free(p->dep_keygen); keygen_free(p->keygen); } struct params * params_combine(struct params *p1, struct params *p2) { struct params *p; if (p1) p = p1; else p = params_new(); if (!p2) return p; if (p2->algorithm) string_assign(&p->algorithm, p2->algorithm); if (p2->ivmeth) string_assign(&p->ivmeth, p2->ivmeth); if (p2->keylen != (size_t)-1) p->keylen = p2->keylen; if (p2->bsize != (size_t)-1) p->bsize = p2->bsize; if (p2->verify_method != VERIFY_UNKNOWN) p->verify_method = p2->verify_method; p->dep_keygen = keygen_combine(p->dep_keygen, p2->dep_keygen); keygen_addlist(&p->keygen, p2->keygen); /* * at this point we should have moved all allocated data * in p2 into p, so we can free it. */ free(p2); return p; } int params_filldefaults(struct params *p) { size_t i; if (p->verify_method == VERIFY_UNKNOWN) p->verify_method = VERIFY_NONE; if (!p->ivmeth) p->ivmeth = string_fromcharstar("encblkno1"); if (p->keylen == (size_t)-1) { i = crypt_defaults_lookup(string_tocharstar(p->algorithm)); if (i != (size_t)-1) { p->keylen = crypto_defaults[i].keylen; } else { warnx("could not determine key length for unknown " "algorithm \"%s\"", string_tocharstar(p->algorithm)); return -1; } } return 0; } /* * params_verify traverses the parameters and all of the keygen methods * looking for inconsistencies. It outputs warnings on non-fatal errors * such as unknown encryption methods, but returns failure on fatal * conditions such as a PKCS5_PBKDF2 keygen without a salt. It is intended * to run before key generation. */ int params_verify(const struct params *p) { static const char *encblkno[] = { "encblkno", "encblkno1", "encblkno8" }; static size_t i; const char *meth; if (!p->algorithm) { warnx("unspecified algorithm"); return 0; } /* * we only warn for the encryption method so that it is possible * to use an older cgdconfig(8) with a new kernel that supports * additional crypto algorithms. */ if (crypt_defaults_lookup(string_tocharstar(p->algorithm)) == -1) warnx("unknown algorithm \"%s\"(warning)", string_tocharstar(p->algorithm)); /* same rationale with IV methods. */ if (!p->ivmeth) { warnx("unspecified IV method"); return 0; } meth = string_tocharstar(p->ivmeth); for (i = 0; i < __arraycount(encblkno); i++) if (strcmp(encblkno[i], meth) == 0) break; if (i == __arraycount(encblkno)) warnx("unknown IV method \"%s\" (warning)", meth); if (p->keylen == (size_t)-1) { warnx("unspecified key length"); return 0; } return keygen_verify(p->keygen); } struct params * params_algorithm(string_t *in) { struct params *p = params_new(); p->algorithm = in; return p; } struct params * params_ivmeth(string_t *in) { struct params *p = params_new(); p->ivmeth = in; return p; } struct params * params_keylen(size_t in) { struct params *p = params_new(); p->keylen = in; return p; } struct params * params_bsize(size_t in) { struct params *p = params_new(); p->bsize = in; return p; } struct params * params_verify_method(string_t *in) { struct params *p = params_new(); const char *vm = string_tocharstar(in); if (!strcmp("none", vm)) p->verify_method = VERIFY_NONE; if (!strcmp("disklabel", vm)) p->verify_method = VERIFY_DISKLABEL; if (!strcmp("ffs", vm)) p->verify_method = VERIFY_FFS; if (!strcmp("re-enter", vm)) p->verify_method = VERIFY_REENTER; if (!strcmp("mbr", vm)) p->verify_method = VERIFY_MBR; if (!strcmp("gpt", vm)) p->verify_method = VERIFY_GPT; string_free(in); if (p->verify_method == VERIFY_UNKNOWN) warnx("params_setverify_method: unrecognized " "verify method \"%s\"", vm); return p; } struct params * params_keygen(struct keygen *in) { struct params *p = params_new(); p->keygen = in; return p; } struct params * params_dep_keygen(struct keygen *in) { struct params *p = params_new(); p->dep_keygen = in; return p; } struct keygen * keygen_new(void) { struct keygen *kg; kg = emalloc(sizeof(*kg)); kg->kg_method = KEYGEN_UNKNOWN; kg->kg_iterations = (size_t)-1; kg->kg_salt = NULL; kg->kg_key = NULL; kg->kg_cmd = NULL; kg->next = NULL; return kg; } void keygen_free(struct keygen *kg) { if (!kg) return; bits_free(kg->kg_salt); bits_free(kg->kg_key); string_free(kg->kg_cmd); keygen_free(kg->next); free(kg); } /* * keygen_verify traverses the keygen structures and ensures * that the appropriate information is available. */ int keygen_verify(const struct keygen *kg) { if (!kg) return 1; switch (kg->kg_method) { case KEYGEN_PKCS5_PBKDF2_OLD: if (kg->kg_iterations == (size_t)-1) { warnx("keygen pkcs5_pbkdf2 must provide `iterations'"); return 0; } if (kg->kg_key) warnx("keygen pkcs5_pbkdf2 does not need a `key'"); if (!kg->kg_salt) { warnx("keygen pkcs5_pbkdf2 must provide a salt"); return 0; } if (kg->kg_cmd) warnx("keygen pkcs5_pbkdf2 does not need a `cmd'"); break; case KEYGEN_PKCS5_PBKDF2_SHA1: if (kg->kg_iterations == (size_t)-1) { warnx("keygen pkcs5_pbkdf2/sha1 must provide `iterations'"); return 0; } if (kg->kg_key) warnx("keygen pkcs5_pbkdf2/sha1 does not need a `key'"); if (!kg->kg_salt) { warnx("keygen pkcs5_pbkdf2/sha1 must provide a salt"); return 0; } if (kg->kg_cmd) warnx("keygen pkcs5_pbkdf2/sha1 does not need a `cmd'"); break; case KEYGEN_STOREDKEY: if (kg->kg_iterations != (size_t)-1) warnx("keygen storedkey does not need `iterations'"); if (!kg->kg_key) { warnx("keygen storedkey must provide a key"); return 0; } if (kg->kg_salt) warnx("keygen storedkey does not need `salt'"); if (kg->kg_cmd) warnx("keygen storedkey does not need `cmd'"); break; case KEYGEN_RANDOMKEY: case KEYGEN_URANDOMKEY: if (kg->kg_iterations != (size_t)-1) warnx("keygen [u]randomkey does not need `iterations'"); if (kg->kg_key) warnx("keygen [u]randomkey does not need `key'"); if (kg->kg_salt) warnx("keygen [u]randomkey does not need `salt'"); if (kg->kg_cmd) warnx("keygen [u]randomkey does not need `cmd'"); break; case KEYGEN_SHELL_CMD: if (kg->kg_iterations != (size_t)-1) warnx("keygen shell_cmd does not need `iterations'"); if (kg->kg_key) warnx("keygen shell_cmd does not need `key'"); if (kg->kg_salt) warnx("keygen shell_cmd does not need `salt'"); if (!kg->kg_cmd) { warnx("keygen shell_cmd must provide a `cmd'"); return 0; } break; } return keygen_verify(kg->next); } struct keygen * keygen_generate(int method) { struct keygen *kg; kg = keygen_new(); if (!kg) return NULL; kg->kg_method = method; return kg; } /* * keygen_filldefaults walks the keygen list and fills in * default values. The defaults may be either calibrated * or randomly generated so this function is designed to be * called when generating a new parameters file, not when * reading a parameters file. */ int keygen_filldefaults(struct keygen *kg, size_t keylen) { if (!kg) return 0; switch (kg->kg_method) { case KEYGEN_RANDOMKEY: case KEYGEN_URANDOMKEY: case KEYGEN_SHELL_CMD: break; case KEYGEN_PKCS5_PBKDF2_OLD: case KEYGEN_PKCS5_PBKDF2_SHA1: kg->kg_salt = bits_getrandombits(DEFAULT_SALTLEN, 1); kg->kg_iterations = pkcs5_pbkdf2_calibrate(BITS2BYTES(keylen), DEFAULT_ITERATION_TIME); if (kg->kg_iterations < 1) { warnx("could not calibrate pkcs5_pbkdf2"); return -1; } break; case KEYGEN_STOREDKEY: /* Generate a random stored key */ kg->kg_key = bits_getrandombits(keylen, 1); if (!kg->kg_key) { warnx("can't generate random bits for storedkey"); return -1; } break; default: return -1; } return keygen_filldefaults(kg->next, keylen); } struct keygen * keygen_combine(struct keygen *kg1, struct keygen *kg2) { if (!kg1 && !kg2) return NULL; if (!kg1) kg1 = keygen_new(); if (!kg2) return kg1; if (kg2->kg_method != KEYGEN_UNKNOWN) kg1->kg_method = kg2->kg_method; if (kg2->kg_iterations != (size_t)-1 && kg2->kg_iterations > 0) kg1->kg_iterations = kg2->kg_iterations; if (kg2->kg_salt) bits_assign(&kg1->kg_salt, kg2->kg_salt); if (kg2->kg_key) bits_assign(&kg1->kg_key, kg2->kg_key); if (kg2->kg_cmd) string_assign(&kg1->kg_cmd, kg2->kg_cmd); return kg1; } struct keygen * keygen_method(string_t *in) { struct keygen *kg = keygen_new(); const char *kgm = string_tocharstar(in); if (!strcmp("pkcs5_pbkdf2", kgm)) kg->kg_method = KEYGEN_PKCS5_PBKDF2_OLD; if (!strcmp("pkcs5_pbkdf2/sha1", kgm)) kg->kg_method = KEYGEN_PKCS5_PBKDF2_SHA1; if (!strcmp("randomkey", kgm)) kg->kg_method = KEYGEN_RANDOMKEY; if (!strcmp("storedkey", kgm)) kg->kg_method = KEYGEN_STOREDKEY; if (!strcmp("urandomkey", kgm)) kg->kg_method = KEYGEN_URANDOMKEY; if (!strcmp("shell_cmd", kgm)) kg->kg_method = KEYGEN_SHELL_CMD; string_free(in); if (kg->kg_method == KEYGEN_UNKNOWN) warnx("unrecognized key generation method \"%s\"", kgm); return kg; } struct keygen * keygen_set_method(struct keygen *kg, string_t *in) { return keygen_combine(kg, keygen_method(in)); } struct keygen * keygen_salt(bits_t *in) { struct keygen *kg = keygen_new(); kg->kg_salt = in; return kg; } struct keygen * keygen_iterations(size_t in) { struct keygen *kg = keygen_new(); kg->kg_iterations = in; return kg; } void keygen_addlist(struct keygen **l, struct keygen *e) { struct keygen *t; if (*l) { t = *l; for (;t->next; t = t->next) ; t->next = e; } else { *l = e; } } struct keygen * keygen_key(bits_t *in) { struct keygen *kg = keygen_new(); kg->kg_key = in; return kg; } struct keygen * keygen_cmd(string_t *in) { struct keygen *kg = keygen_new(); kg->kg_cmd = in; return kg; } struct params * params_fget(FILE *f) { struct params *p; p = cgdparsefile(f); if (!p) return NULL; /* * We deal with the deprecated keygen structure by prepending it * to the list of keygens, so that the rest of the code does not * have to deal with this backwards compat issue. The deprecated * ``xor_key'' field may be stored in p->dep_keygen->kg_key. If * it exists, we construct a storedkey keygen struct as well. Also, * default the iteration count to 128 as the old code did. */ if (p->dep_keygen) { if (p->dep_keygen->kg_iterations == (size_t)-1) p->dep_keygen->kg_iterations = 128; p->dep_keygen->next = p->keygen; if (p->dep_keygen->kg_key) { p->keygen = keygen_generate(KEYGEN_STOREDKEY); p->keygen->kg_key = p->dep_keygen->kg_key; p->dep_keygen->kg_key = NULL; p->keygen->next = p->dep_keygen; } else { p->keygen = p->dep_keygen; } p->dep_keygen = NULL; } return p; } struct params * params_cget(const char *fn) { struct params *p; FILE *f; char filename[MAXPATHLEN]; if ((f = fopen(fn, "r")) == NULL && fn[0] != '/') { snprintf(filename, sizeof(filename), "%s/%s", CGDCONFIG_DIR, fn); fn = filename; f = fopen(fn, "r"); } if (f == NULL) { warn("failed to open params file \"%s\"", fn); return NULL; } p = params_fget(f); (void)fclose(f); return p; } #define WRAP_COL 50 #define TAB_COL 8 static void spaces(FILE *f, int len) { while (len-- > 0) (void)fputc(' ', f); } static void print_kvpair_cstr(FILE *f, int ts, const char *key, const char *val) { spaces(f, ts); (void)fprintf(f, "%s %s;\n", key, val); } static void print_kvpair_string(FILE *f, int ts, const char *key, const string_t *val) { print_kvpair_cstr(f, ts, key, string_tocharstar(val)); } static void print_kvpair_int(FILE *f, int ts, const char *key, size_t val) { char *tmp; if (!key || val == (size_t)-1) return; if (asprintf(&tmp, "%zu", val) == -1) err(1, NULL); print_kvpair_cstr(f, ts, key, tmp); free(tmp); } /* * prints out a base64 encoded k-v pair to f. It encodes the length * of the bitstream as a 32bit unsigned integer in network byte order * up front. */ static void print_kvpair_b64(FILE *f, int curpos, int ts, const char *key, bits_t *val) { string_t *str; int i; int len; int pos; const char *out; if (!key || !val) return; str = bits_encode(val); out = string_tocharstar(str); len = strlen(out); spaces(f, ts); (void)fprintf(f, "%s ", key); curpos += ts + strlen(key) + 1; ts = curpos; for (i=0, pos=curpos; i < len; i++, pos++) { if (pos > WRAP_COL) { (void)fprintf(f, " \\\n"); spaces(f, ts); pos = ts; } (void)fputc(out[i], f); } (void)fprintf(f, ";\n"); string_free(str); } int keygen_fput(struct keygen *kg, int ts, FILE *f) { int curpos = 0; if (!kg) return 0; (void)fprintf(f, "keygen "); curpos += strlen("keygen "); switch (kg->kg_method) { case KEYGEN_STOREDKEY: (void)fprintf(f, "storedkey "); curpos += strlen("storedkey "); print_kvpair_b64(f, curpos, 0, "key", kg->kg_key); break; case KEYGEN_RANDOMKEY: (void)fprintf(f, "randomkey;\n"); break; case KEYGEN_URANDOMKEY: (void)fprintf(f, "urandomkey;\n"); break; case KEYGEN_PKCS5_PBKDF2_OLD: (void)fprintf(f, "pkcs5_pbkdf2 {\n"); print_kvpair_int(f, ts, "iterations", kg->kg_iterations); print_kvpair_b64(f, 0, ts, "salt", kg->kg_salt); (void)fprintf(f, "};\n"); break; case KEYGEN_PKCS5_PBKDF2_SHA1: (void)fprintf(f, "pkcs5_pbkdf2/sha1 {\n"); print_kvpair_int(f, ts, "iterations", kg->kg_iterations); print_kvpair_b64(f, 0, ts, "salt", kg->kg_salt); (void)fprintf(f, "};\n"); break; default: warnx("keygen_fput: %d not a valid method", kg->kg_method); break; } return keygen_fput(kg->next, ts, f); } int params_fput(struct params *p, FILE *f) { int ts = 0; /* tabstop of 0 spaces */ print_kvpair_string(f, ts, "algorithm", p->algorithm); print_kvpair_string(f, ts, "iv-method", p->ivmeth); print_kvpair_int(f, ts, "keylength", p->keylen); print_kvpair_int(f, ts, "blocksize", p->bsize); switch (p->verify_method) { case VERIFY_NONE: print_kvpair_cstr(f, ts, "verify_method", "none"); break; case VERIFY_DISKLABEL: print_kvpair_cstr(f, ts, "verify_method", "disklabel"); break; case VERIFY_FFS: print_kvpair_cstr(f, ts, "verify_method", "ffs"); break; case VERIFY_REENTER: print_kvpair_cstr(f, ts, "verify_method", "re-enter"); break; case VERIFY_MBR: print_kvpair_cstr(f, ts, "verify_method", "mbr"); break; case VERIFY_GPT: print_kvpair_cstr(f, ts, "verify_method", "gpt"); break; default: warnx("unsupported verify_method (%d)", p->verify_method); return -1; } return keygen_fput(p->keygen, TAB_COL, f); } int params_cput(struct params *p, const char *fn) { FILE *f; if (fn && *fn) { if ((f = fopen(fn, "w")) == NULL) { warn("could not open outfile \"%s\"", fn); return -1; } } else { f = stdout; } return params_fput(p, f); } static int crypt_defaults_lookup(const char *alg) { unsigned i; for (i=0; i < (sizeof(crypto_defaults) / sizeof(crypto_defaults[0])); i++) if (!strcmp(alg, crypto_defaults[i].alg)) return i; return -1; }