/* certreqgen.c - Generate a key and a certification request * Copyright (C) 2002, 2003 Free Software Foundation, Inc. * * This file is part of GnuPG. * * GnuPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * GnuPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA */ /* The format of the native parameter file is follows: o Text only, line length is limited to about 1000 chars. o You must use UTF-8 encoding to specify non-ascii characters. o Empty lines are ignored. o Leading and trailing spaces are ignored. o A hash sign as the first non white space character is a comment line. o Control statements are indicated by a leading percent sign, the arguments are separated by white space from the keyword. o Parameters are specified by a keyword, followed by a colon. Arguments are separated by white space. o The first parameter must be "Key-Type", control statements may be placed anywhere. o Key generation takes place when either the end of the parameter file is reached, the next "Key-Type" parameter is encountered or at the controlstatement "%commit" o Control statements: %echo Print . %dry-run Suppress actual key generation (useful for syntax checking). %commit Perform the key generation. Note that an implicit commit is done at the next "Key-Type" parameter. %certfile Do not write the certificate to the keyDB but to . This must be given before the first commit to take place, duplicate specification of the same filename is ignored, the last filename before a commit is used. The filename is used until a new filename is used (at commit points) and all keys are written to that file. If a new filename is given, this file is created (and overwrites an existing one). Both control statements must be given. o The order of the parameters does not matter except for "Key-Type" which must be the first parameter. The parameters are only for the generated keyblock and parameters from previous key generations are not used. Some syntactically checks may be performed. The currently defined parameters are: Key-Type: Starts a new parameter block by giving the type of the primary key. The algorithm must be capable of signing. This is a required parameter. For now the only supported algorithm is "rsa". Key-Length: Length of the key in bits. Default is 1024. Key-Usage: Space or comma delimited list of key usage, allowed values are "encrypt" and "sign". This is used to generate the KeyUsage extension. Please make sure that the algorithm is capable of this usage. Default is to allow encrypt and sign. Name-DN: subject name This is the DN name of the subject in rfc2253 format. Name-Email: The ist the email address Here is an example: $ cat >foo < #include #include #include #include #include #include #include #include "gpgsm.h" #include #include #include "keydb.h" #include "i18n.h" enum para_name { pKEYTYPE, pKEYLENGTH, pKEYUSAGE, pNAMEDN, pNAMEEMAIL }; struct para_data_s { struct para_data_s *next; int lnr; enum para_name key; union { unsigned int usage; char value[1]; } u; }; struct reqgen_ctrl_s { int lnr; int dryrun; ksba_writer_t writer; }; static const char oidstr_keyUsage[] = "2.5.29.15"; static int proc_parameters (ctrl_t ctrl, struct para_data_s *para, struct reqgen_ctrl_s *outctrl); static int create_request (ctrl_t ctrl, struct para_data_s *para, ksba_const_sexp_t public, struct reqgen_ctrl_s *outctrl); static void release_parameter_list (struct para_data_s *r) { struct para_data_s *r2; for (; r ; r = r2) { r2 = r->next; xfree(r); } } static struct para_data_s * get_parameter (struct para_data_s *para, enum para_name key) { struct para_data_s *r; for (r = para; r && r->key != key; r = r->next) ; return r; } static const char * get_parameter_value (struct para_data_s *para, enum para_name key) { struct para_data_s *r = get_parameter (para, key); return (r && *r->u.value)? r->u.value : NULL; } static int get_parameter_algo (struct para_data_s *para, enum para_name key) { struct para_data_s *r = get_parameter (para, key); if (!r) return -1; if (digitp (r->u.value)) return atoi( r->u.value ); return gcry_pk_map_name (r->u.value); } /* Parse the usage parameter. Returns 0 on success. Note that we only care about sign and encrypt and don't (yet) allow all the other X.509 usage to be specified; instead we will use a fixed mapping to the X.509 usage flags. */ static int parse_parameter_usage (struct para_data_s *para, enum para_name key) { struct para_data_s *r = get_parameter (para, key); char *p, *pn; unsigned int use; if (!r) return 0; /* none (this is an optional parameter)*/ use = 0; pn = r->u.value; while ( (p = strsep (&pn, " \t,")) ) { if (!*p) ; else if ( !ascii_strcasecmp (p, "sign") ) use |= GCRY_PK_USAGE_SIGN; else if ( !ascii_strcasecmp (p, "encrypt") ) use |= GCRY_PK_USAGE_ENCR; else { log_error ("line %d: invalid usage list\n", r->lnr); return -1; /* error */ } } r->u.usage = use; return 0; } static unsigned int get_parameter_uint (struct para_data_s *para, enum para_name key) { struct para_data_s *r = get_parameter (para, key); if (!r) return 0; if (r->key == pKEYUSAGE) return r->u.usage; return (unsigned int)strtoul (r->u.value, NULL, 10); } /* Read the certificate generation parameters from FP and generate (all) certificate requests. */ static int read_parameters (ctrl_t ctrl, FILE *fp, ksba_writer_t writer) { static struct { const char *name; enum para_name key; } keywords[] = { { "Key-Type", pKEYTYPE}, { "Key-Length", pKEYLENGTH }, { "Key-Usage", pKEYUSAGE }, { "Name-DN", pNAMEDN }, { "Name-Email", pNAMEEMAIL }, { NULL, 0 } }; char line[1024], *p; const char *err = NULL; struct para_data_s *para, *r; int i, rc = 0, any = 0; struct reqgen_ctrl_s outctrl; memset (&outctrl, 0, sizeof (outctrl)); outctrl.writer = writer; err = NULL; para = NULL; while (fgets (line, DIM(line)-1, fp) ) { char *keyword, *value; outctrl.lnr++; if (*line && line[strlen(line)-1] != '\n') { err = "line too long"; break; } for (p=line; spacep (p); p++) ; if (!*p || *p == '#') continue; keyword = p; if (*keyword == '%') { for (; *p && !spacep (p); p++) ; if (*p) *p++ = 0; for (; spacep (p); p++) ; value = p; trim_trailing_spaces (value); if (!ascii_strcasecmp (keyword, "%echo")) log_info ("%s\n", value); else if (!ascii_strcasecmp (keyword, "%dry-run")) outctrl.dryrun = 1; else if (!ascii_strcasecmp( keyword, "%commit")) { rc = proc_parameters (ctrl, para, &outctrl); if (rc) goto leave; any = 1; release_parameter_list (para); para = NULL; } else log_info ("skipping control `%s' (%s)\n", keyword, value); continue; } if (!(p = strchr (p, ':')) || p == keyword) { err = "missing colon"; break; } if (*p) *p++ = 0; for (; spacep (p); p++) ; if (!*p) { err = "missing argument"; break; } value = p; trim_trailing_spaces (value); for (i=0; (keywords[i].name && ascii_strcasecmp (keywords[i].name, keyword)); i++) ; if (!keywords[i].name) { err = "unknown keyword"; break; } if (keywords[i].key != pKEYTYPE && !para) { err = "parameter block does not start with \"Key-Type\""; break; } if (keywords[i].key == pKEYTYPE && para) { rc = proc_parameters (ctrl, para, &outctrl); if (rc) goto leave; any = 1; release_parameter_list (para); para = NULL; } else { for (r = para; r && r->key != keywords[i].key; r = r->next) ; if (r) { err = "duplicate keyword"; break; } } r = xtrycalloc (1, sizeof *r + strlen( value )); if (!r) { err = "out of core"; break; } r->lnr = outctrl.lnr; r->key = keywords[i].key; strcpy (r->u.value, value); r->next = para; para = r; } if (err) { log_error ("line %d: %s\n", outctrl.lnr, err); rc = gpg_error (GPG_ERR_GENERAL); } else if (ferror(fp)) { log_error ("line %d: read error: %s\n", outctrl.lnr, strerror(errno) ); rc = gpg_error (GPG_ERR_GENERAL); } else if (para) { rc = proc_parameters (ctrl, para, &outctrl); if (rc) goto leave; any = 1; } if (!rc && !any) rc = gpg_error (GPG_ERR_NO_DATA); leave: release_parameter_list (para); return rc; } /* check whether there are invalid characters in the email address S */ static int has_invalid_email_chars (const char *s) { int at_seen=0; static char valid_chars[] = "01234567890_-." "abcdefghijklmnopqrstuvwxyz" "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; for (; *s; s++) { if (*s & 0x80) return 1; if (*s == '@') at_seen++; else if (!at_seen && !( !!strchr (valid_chars, *s) || *s == '+')) return 1; else if (at_seen && !strchr (valid_chars, *s)) return 1; } return at_seen != 1; } /* Check that all required parameters are given and perform the action */ static int proc_parameters (ctrl_t ctrl, struct para_data_s *para, struct reqgen_ctrl_s *outctrl) { struct para_data_s *r; const char *s; int i; unsigned int nbits; char numbuf[20]; unsigned char keyparms[100]; int rc; ksba_sexp_t public; /* check that we have all required parameters */ assert (get_parameter (para, pKEYTYPE)); /* We can only use RSA for now. There is a with pkcs-10 on how to use ElGamal because it is expected that a PK algorithm can always be used for signing. */ i = get_parameter_algo (para, pKEYTYPE); if (i < 1 || i != GCRY_PK_RSA ) { r = get_parameter (para, pKEYTYPE); log_error (_("line %d: invalid algorithm\n"), r->lnr); return gpg_error (GPG_ERR_INV_PARAMETER); } /* check the keylength */ if (!get_parameter (para, pKEYLENGTH)) nbits = 1024; else nbits = get_parameter_uint (para, pKEYLENGTH); if (nbits < 1024 || nbits > 4096) { /* The BSI specs dated 2002-11-25 don't allow lengths below 1024. */ r = get_parameter (para, pKEYTYPE); log_error (_("line %d: invalid key length %u (valid are %d to %d)\n"), r->lnr, nbits, 1024, 4096); return gpg_error (GPG_ERR_INV_PARAMETER); } /* check the usage */ if (parse_parameter_usage (para, pKEYUSAGE)) return gpg_error (GPG_ERR_INV_PARAMETER); /* check that there is a subject name and that this DN fits our requirements */ if (!(s=get_parameter_value (para, pNAMEDN))) { r = get_parameter (para, pKEYTYPE); log_error (_("line %d: no subject name given\n"), r->lnr); return gpg_error (GPG_ERR_INV_PARAMETER); } /* fixme check s */ /* check that the optional email address is okay */ if ((s=get_parameter_value (para, pNAMEEMAIL))) { if (has_invalid_email_chars (s) || *s == '@' || s[strlen(s)-1] == '@' || s[strlen(s)-1] == '.' || strstr(s, "..")) { r = get_parameter (para, pKEYTYPE); log_error (_("line %d: not a valid email address\n"), r->lnr); return gpg_error (GPG_ERR_INV_PARAMETER); } } sprintf (numbuf, "%u", nbits); snprintf (keyparms, DIM (keyparms)-1, "(6:genkey(3:rsa(5:nbits%d:%s)))", (int)strlen (numbuf), numbuf); rc = gpgsm_agent_genkey (ctrl, keyparms, &public); if (rc) { r = get_parameter (para, pKEYTYPE); log_error (_("line %d: key generation failed: %s\n"), r->lnr, gpg_strerror (rc)); return rc; } rc = create_request (ctrl, para, public, outctrl); xfree (public); return rc; } /* Parameters are checked, the key pair has been created. Now generate the request and write it out */ static int create_request (ctrl_t ctrl, struct para_data_s *para, ksba_const_sexp_t public, struct reqgen_ctrl_s *outctrl) { ksba_certreq_t cr; gpg_error_t err; gcry_md_hd_t md; ksba_stop_reason_t stopreason; int rc = 0; const char *s; unsigned int use; err = ksba_certreq_new (&cr); if (err) return err; rc = gcry_md_open (&md, GCRY_MD_SHA1, 0); if (rc) { log_error ("md_open failed: %s\n", gpg_strerror (rc)); goto leave; } if (DBG_HASHING) gcry_md_start_debug (md, "cr.cri"); ksba_certreq_set_hash_function (cr, HASH_FNC, md); ksba_certreq_set_writer (cr, outctrl->writer); err = ksba_certreq_add_subject (cr, get_parameter_value (para, pNAMEDN)); if (err) { log_error ("error setting the subject's name: %s\n", gpg_strerror (err)); rc = err; goto leave; } s = get_parameter_value (para, pNAMEEMAIL); if (s) { char *buf; buf = xtrymalloc (strlen (s) + 3); if (!buf) { rc = OUT_OF_CORE (errno); goto leave; } *buf = '<'; strcpy (buf+1, s); strcat (buf+1, ">"); err = ksba_certreq_add_subject (cr, buf); xfree (buf); if (err) { log_error ("error setting the subject's alternate name: %s\n", gpg_strerror (err)); rc = err; goto leave; } } err = ksba_certreq_set_public_key (cr, public); if (err) { log_error ("error setting the public key: %s\n", gpg_strerror (err)); rc = err; goto leave; } use = get_parameter_uint (para, pKEYUSAGE); if (use == GCRY_PK_USAGE_SIGN) { /* For signing only we encode the bits: KSBA_KEYUSAGE_DIGITAL_SIGNATURE KSBA_KEYUSAGE_NON_REPUDIATION */ err = ksba_certreq_add_extension (cr, oidstr_keyUsage, 1, "\x03\x02\x06\xC0", 4); } else if (use == GCRY_PK_USAGE_ENCR) { /* For encrypt only we encode the bits: KSBA_KEYUSAGE_KEY_ENCIPHERMENT KSBA_KEYUSAGE_DATA_ENCIPHERMENT */ err = ksba_certreq_add_extension (cr, oidstr_keyUsage, 1, "\x03\x02\x04\x30", 4); } else err = 0; /* Both or none given: don't request one. */ if (err) { log_error ("error setting the key usage: %s\n", gpg_strerror (err)); rc = err; goto leave; } do { err = ksba_certreq_build (cr, &stopreason); if (err) { log_error ("ksba_certreq_build failed: %s\n", gpg_strerror (err)); rc = err; goto leave; } if (stopreason == KSBA_SR_NEED_SIG) { gcry_sexp_t s_pkey; size_t n; unsigned char grip[20], hexgrip[41]; char *sigval; size_t siglen; n = gcry_sexp_canon_len (public, 0, NULL, NULL); if (!n) { log_error ("libksba did not return a proper S-Exp\n"); err = gpg_error (GPG_ERR_BUG); goto leave; } rc = gcry_sexp_sscan (&s_pkey, NULL, public, n); if (rc) { log_error ("gcry_sexp_scan failed: %s\n", gpg_strerror (rc)); goto leave; } if ( !gcry_pk_get_keygrip (s_pkey, grip) ) { rc = gpg_error (GPG_ERR_GENERAL); log_error ("can't figure out the keygrip\n"); gcry_sexp_release (s_pkey); goto leave; } gcry_sexp_release (s_pkey); for (n=0; n < 20; n++) sprintf (hexgrip+n*2, "%02X", grip[n]); rc = gpgsm_agent_pksign (ctrl, hexgrip, NULL, gcry_md_read(md, GCRY_MD_SHA1), gcry_md_get_algo_dlen (GCRY_MD_SHA1), GCRY_MD_SHA1, &sigval, &siglen); if (rc) { log_error ("signing failed: %s\n", gpg_strerror (rc)); goto leave; } err = ksba_certreq_set_sig_val (cr, sigval); xfree (sigval); if (err) { log_error ("failed to store the sig_val: %s\n", gpg_strerror (err)); rc = err; goto leave; } } } while (stopreason != KSBA_SR_READY); leave: gcry_md_close (md); ksba_certreq_release (cr); return rc; } /* Create a new key by reading the parameters from in_fd. Multiple keys may be created */ int gpgsm_genkey (ctrl_t ctrl, int in_fd, FILE *out_fp) { int rc; FILE *in_fp; Base64Context b64writer = NULL; ksba_writer_t writer; in_fp = fdopen (dup (in_fd), "rb"); if (!in_fp) { gpg_error_t tmperr = gpg_error (gpg_err_code_from_errno (errno)); log_error ("fdopen() failed: %s\n", strerror (errno)); return tmperr; } ctrl->pem_name = "CERTIFICATE REQUEST"; rc = gpgsm_create_writer (&b64writer, ctrl, out_fp, &writer); if (rc) { log_error ("can't create writer: %s\n", gpg_strerror (rc)); goto leave; } rc = read_parameters (ctrl, in_fp, writer); if (rc) { log_error ("error creating certificate request: %s\n", gpg_strerror (rc)); goto leave; } rc = gpgsm_finish_writer (b64writer); if (rc) { log_error ("write failed: %s\n", gpg_strerror (rc)); goto leave; } gpgsm_status (ctrl, STATUS_KEY_CREATED, "P"); log_info ("certificate request created\n"); leave: gpgsm_destroy_writer (b64writer); fclose (in_fp); return rc; }