dst_api.c

#ifndef LINT static const char rcsid[] = "$Header: /proj/cvs/prod/libbind/dst/dst_api.c,v 1.17 2007/09/24 17:18:25 each Exp $"; #endif /* * Portions Copyright (c) 1995-1998 by Trusted Information Systems, Inc. * * Permission to use, copy modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND TRUSTED INFORMATION SYSTEMS * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL * TRUSTED INFORMATION SYSTEMS BE LIABLE FOR ANY SPECIAL, DIRECT, * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION * WITH THE USE OR PERFORMANCE OF THE SOFTWARE. */ /* * This file contains the interface between the DST API and the crypto API. * This is the only file that needs to be changed if the crypto system is * changed. Exported functions are: * void dst_init() Initialize the toolkit * int dst_check_algorithm() Function to determines if alg is suppored. * int dst_compare_keys() Function to compare two keys for equality. * int dst_sign_data() Incremental signing routine. * int dst_verify_data() Incremental verify routine. * int dst_generate_key() Function to generate new KEY * DST_KEY *dst_read_key() Function to retrieve private/public KEY. * void dst_write_key() Function to write out a key. * DST_KEY *dst_dnskey_to_key() Function to convert DNS KEY RR to a DST * KEY structure. * int dst_key_to_dnskey() Function to return a public key in DNS * format binary * DST_KEY *dst_buffer_to_key() Converst a data in buffer to KEY * int *dst_key_to_buffer() Writes out DST_KEY key matterial in buffer * void dst_free_key() Releases all memory referenced by key structure */ #include "port_before.h" #include <stdio.h> #include <errno.h> #include <fcntl.h> #include <stdlib.h> #include <unistd.h> #include <string.h> #include <memory.h> #include <ctype.h> #include <time.h> #include <sys/param.h> #include <sys/stat.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/nameser.h> #include <resolv.h> #include "dst_internal.h" #include "port_after.h" /* static variables */ static int done_init = 0; dst_func *dst_t_func[DST_MAX_ALGS]; const char *key_file_fmt_str = "Private-key-format: v%s\nAlgorithm: %d (%s)\n"; const char *dst_path = ""; /* internal I/O functions */ static DST_KEY *dst_s_read_public_key(const char *in_name, const u_int16_t in_id, int in_alg); static int dst_s_read_private_key_file(char *name, DST_KEY *pk_key, u_int16_t in_id, int in_alg); static int dst_s_write_public_key(const DST_KEY *key); static int dst_s_write_private_key(const DST_KEY *key); /* internal function to set up data structure */ static DST_KEY *dst_s_get_key_struct(const char *name, const int alg, const int flags, const int protocol, const int bits); /*% * dst_init * This function initializes the Digital Signature Toolkit. * Right now, it just checks the DSTKEYPATH environment variable. * Parameters * none * Returns * none */ void dst_init() { char *s; int len; if (done_init != 0) return; done_init = 1; s = getenv("DSTKEYPATH"); len = 0; if (s) { struct stat statbuf; len = strlen(s); if (len > PATH_MAX) { EREPORT(("%s is longer than %d characters, ignoring\n", s, PATH_MAX)); } else if (stat(s, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode)) { EREPORT(("%s is not a valid directory\n", s)); } else { char *tmp; tmp = (char *) malloc(len + 2); memcpy(tmp, s, len + 1); if (tmp[strlen(tmp) - 1] != '/') { tmp[strlen(tmp) + 1] = 0; tmp[strlen(tmp)] = '/'; } dst_path = tmp; } } memset(dst_t_func, 0, sizeof(dst_t_func)); /* first one is selected */ dst_hmac_md5_init(); } /*% * dst_check_algorithm * This function determines if the crypto system for the specified * algorithm is present. * Parameters * alg 1 KEY_RSA * 3 KEY_DSA * 157 KEY_HMAC_MD5 * future algorithms TBD and registered with IANA. * Returns * 1 - The algorithm is available. * 0 - The algorithm is not available. */ int dst_check_algorithm(const int alg) { return (dst_t_func[alg] != NULL); } /*% * dst_s_get_key_struct * This function allocates key structure and fills in some of the * fields of the structure. * Parameters: * name: the name of the key * alg: the algorithm number * flags: the dns flags of the key * protocol: the dns protocol of the key * bits: the size of the key * Returns: * NULL if error * valid pointer otherwise */ static DST_KEY * dst_s_get_key_struct(const char *name, const int alg, const int flags, const int protocol, const int bits) { DST_KEY *new_key = NULL; if (dst_check_algorithm(alg)) /*%< make sure alg is available */ new_key = (DST_KEY *) malloc(sizeof(*new_key)); if (new_key == NULL) return (NULL); memset(new_key, 0, sizeof(*new_key)); new_key->dk_key_name = strdup(name); if (new_key->dk_key_name == NULL) { free(new_key); return (NULL); } new_key->dk_alg = alg; new_key->dk_flags = flags; new_key->dk_proto = protocol; new_key->dk_KEY_struct = NULL; new_key->dk_key_size = bits; new_key->dk_func = dst_t_func[alg]; return (new_key); } /*% * dst_compare_keys * Compares two keys for equality. * Parameters * key1, key2 Two keys to be compared. * Returns * 0 The keys are equal. * non-zero The keys are not equal. */ int dst_compare_keys(const DST_KEY *key1, const DST_KEY *key2) { if (key1 == key2) return (0); if (key1 == NULL || key2 == NULL) return (4); if (key1->dk_alg != key2->dk_alg) return (1); if (key1->dk_key_size != key2->dk_key_size) return (2); if (key1->dk_id != key2->dk_id) return (3); return (key1->dk_func->compare(key1, key2)); } /*% * dst_sign_data * An incremental signing function. Data is signed in steps. * First the context must be initialized (SIG_MODE_INIT). * Then data is hashed (SIG_MODE_UPDATE). Finally the signature * itself is created (SIG_MODE_FINAL). This function can be called * once with INIT, UPDATE and FINAL modes all set, or it can be * called separately with a different mode set for each step. The * UPDATE step can be repeated. * Parameters * mode A bit mask used to specify operation(s) to be performed. * SIG_MODE_INIT 1 Initialize digest * SIG_MODE_UPDATE 2 Add data to digest * SIG_MODE_FINAL 4 Generate signature * from signature * SIG_MODE_ALL (SIG_MODE_INIT,SIG_MODE_UPDATE,SIG_MODE_FINAL * data Data to be signed. * len The length in bytes of data to be signed. * in_key Contains a private key to sign with. * KEY structures should be handled (created, converted, * compared, stored, freed) by the DST. * signature * The location to which the signature will be written. * sig_len Length of the signature field in bytes. * Return * 0 Successfull INIT or Update operation * >0 success FINAL (sign) operation * <0 failure */ int dst_sign_data(const int mode, DST_KEY *in_key, void **context, const u_char *data, const int len, u_char *signature, const int sig_len) { DUMP(data, mode, len, "dst_sign_data()"); if (mode & SIG_MODE_FINAL && (in_key->dk_KEY_struct == NULL || signature == NULL)) return (MISSING_KEY_OR_SIGNATURE); if (in_key->dk_func && in_key->dk_func->sign) return (in_key->dk_func->sign(mode, in_key, context, data, len, signature, sig_len)); return (UNKNOWN_KEYALG); } /*% * dst_verify_data * An incremental verify function. Data is verified in steps. * First the context must be initialized (SIG_MODE_INIT). * Then data is hashed (SIG_MODE_UPDATE). Finally the signature * is verified (SIG_MODE_FINAL). This function can be called * once with INIT, UPDATE and FINAL modes all set, or it can be * called separately with a different mode set for each step. The * UPDATE step can be repeated. * Parameters * mode Operations to perform this time. * SIG_MODE_INIT 1 Initialize digest * SIG_MODE_UPDATE 2 add data to digest * SIG_MODE_FINAL 4 verify signature * SIG_MODE_ALL * (SIG_MODE_INIT,SIG_MODE_UPDATE,SIG_MODE_FINAL) * data Data to pass through the hash function. * len Length of the data in bytes. * in_key Key for verification. * signature Location of signature. * sig_len Length of the signature in bytes. * Returns * 0 Verify success * Non-Zero Verify Failure */ int dst_verify_data(const int mode, DST_KEY *in_key, void **context, const u_char *data, const int len, const u_char *signature, const int sig_len) { DUMP(data, mode, len, "dst_verify_data()"); if (mode & SIG_MODE_FINAL && (in_key->dk_KEY_struct == NULL || signature == NULL)) return (MISSING_KEY_OR_SIGNATURE); if (in_key->dk_func == NULL || in_key->dk_func->verify == NULL) return (UNSUPPORTED_KEYALG); return (in_key->dk_func->verify(mode, in_key, context, data, len, signature, sig_len)); } /*% * dst_read_private_key * Access a private key. First the list of private keys that have * already been read in is searched, then the key accessed on disk. * If the private key can be found, it is returned. If the key cannot * be found, a null pointer is returned. The options specify required * key characteristics. If the private key requested does not have * these characteristics, it will not be read. * Parameters * in_keyname The private key name. * in_id The id of the private key. * options DST_FORCE_READ Read from disk - don't use a previously * read key. * DST_CAN_SIGN The key must be useable for signing. * DST_NO_AUTHEN The key must be useable for authentication. * DST_STANDARD Return any key * Returns * NULL If there is no key found in the current directory or * this key has not been loaded before. * !NULL Success - KEY structure returned. */ DST_KEY * dst_read_key(const char *in_keyname, const u_int16_t in_id, const int in_alg, const int type) { char keyname[PATH_MAX]; DST_KEY *dg_key = NULL, *pubkey = NULL; if (!dst_check_algorithm(in_alg)) { /*%< make sure alg is available */ EREPORT(("dst_read_private_key(): Algorithm %d not suppored\n", in_alg)); return (NULL); } if ((type & (DST_PUBLIC | DST_PRIVATE)) == 0) return (NULL); if (in_keyname == NULL) { EREPORT(("dst_read_private_key(): Null key name passed in\n")); return (NULL); } else if (strlen(in_keyname) >= sizeof(keyname)) { EREPORT(("dst_read_private_key(): keyname too big\n")); return (NULL); } else strcpy(keyname, in_keyname); /* before I read in the public key, check if it is allowed to sign */ if ((pubkey = dst_s_read_public_key(keyname, in_id, in_alg)) == NULL) return (NULL); if (type == DST_PUBLIC) return pubkey; if (!(dg_key = dst_s_get_key_struct(keyname, pubkey->dk_alg, pubkey->dk_flags, pubkey->dk_proto, 0))) return (dg_key); /* Fill in private key and some fields in the general key structure */ if (dst_s_read_private_key_file(keyname, dg_key, pubkey->dk_id, pubkey->dk_alg) == 0) dg_key = dst_free_key(dg_key); (void)dst_free_key(pubkey); return (dg_key); } int dst_write_key(const DST_KEY *key, const int type) { int pub = 0, priv = 0; if (key == NULL) return (0); if (!dst_check_algorithm(key->dk_alg)) { /*%< make sure alg is available */ EREPORT(("dst_write_key(): Algorithm %d not suppored\n", key->dk_alg)); return (UNSUPPORTED_KEYALG); } if ((type & (DST_PRIVATE|DST_PUBLIC)) == 0) return (0); if (type & DST_PUBLIC) if ((pub = dst_s_write_public_key(key)) < 0) return (pub); if (type & DST_PRIVATE) if ((priv = dst_s_write_private_key(key)) < 0) return (priv); return (priv+pub); } /*% * dst_write_private_key * Write a private key to disk. The filename will be of the form: * K<key->dk_name>+<key->dk_alg+><key-d>k_id.><private key suffix>. * If there is already a file with this name, an error is returned. * * Parameters * key A DST managed key structure that contains * all information needed about a key. * Return * >= 0 Correct behavior. Returns length of encoded key value * written to disk. * < 0 error. */ static int dst_s_write_private_key(const DST_KEY *key) { u_char encoded_block[RAW_KEY_SIZE]; char file[PATH_MAX]; int len; FILE *fp; /* First encode the key into the portable key format */ if (key == NULL) return (-1); if (key->dk_KEY_struct == NULL) return (0); /*%< null key has no private key */ if (key->dk_func == NULL || key->dk_func->to_file_fmt == NULL) { EREPORT(("dst_write_private_key(): Unsupported operation %d\n", key->dk_alg)); return (-5); } else if ((len = key->dk_func->to_file_fmt(key, (char *)encoded_block, sizeof(encoded_block))) <= 0) { EREPORT(("dst_write_private_key(): Failed encoding private RSA bsafe key %d\n", len)); return (-8); } /* Now I can create the file I want to use */ dst_s_build_filename(file, key->dk_key_name, key->dk_id, key->dk_alg, PRIVATE_KEY, PATH_MAX); /* Do not overwrite an existing file */ if ((fp = dst_s_fopen(file, "w", 0600)) != NULL) { int nn; if ((nn = fwrite(encoded_block, 1, len, fp)) != len) { EREPORT(("dst_write_private_key(): Write failure on %s %d != %d errno=%d\n", file, len, nn, errno)); fclose(fp); return (-5); } fclose(fp); } else { EREPORT(("dst_write_private_key(): Can not create file %s\n" ,file)); return (-6); } memset(encoded_block, 0, len); return (len); } /*% * * dst_read_public_key * Read a public key from disk and store in a DST key structure. * Parameters * in_name K<in_name><in_id>.<public key suffix> is the * filename of the key file to be read. * Returns * NULL If the key does not exist or no name is supplied. * NON-NULL Initialized key structure if the key exists. */ static DST_KEY * dst_s_read_public_key(const char *in_name, const u_int16_t in_id, int in_alg) { int flags, proto, alg, len, dlen; int c; char name[PATH_MAX], enckey[RAW_KEY_SIZE], *notspace; u_char deckey[RAW_KEY_SIZE]; FILE *fp; if (in_name == NULL) { EREPORT(("dst_read_public_key(): No key name given\n")); return (NULL); } if (dst_s_build_filename(name, in_name, in_id, in_alg, PUBLIC_KEY, PATH_MAX) == -1) { EREPORT(("dst_read_public_key(): Cannot make filename from %s, %d, and %s\n", in_name, in_id, PUBLIC_KEY)); return (NULL); } /* * Open the file and read it's formatted contents up to key * File format: * domain.name [ttl] [IN] KEY <flags> <protocol> <algorithm> <key> * flags, proto, alg stored as decimal (or hex numbers FIXME). * (FIXME: handle parentheses for line continuation.) */ if ((fp = dst_s_fopen(name, "r", 0)) == NULL) { EREPORT(("dst_read_public_key(): Public Key not found %s\n", name)); return (NULL); } /* Skip domain name, which ends at first blank */ while ((c = getc(fp)) != EOF) if (isspace(c)) break; /* Skip blank to get to next field */ while ((c = getc(fp)) != EOF) if (!isspace(c)) break; /* Skip optional TTL -- if initial digit, skip whole word. */ if (isdigit(c)) { while ((c = getc(fp)) != EOF) if (isspace(c)) break; while ((c = getc(fp)) != EOF) if (!isspace(c)) break; } /* Skip optional "IN" */ if (c == 'I' || c == 'i') { while ((c = getc(fp)) != EOF) if (isspace(c)) break; while ((c = getc(fp)) != EOF) if (!isspace(c)) break; } /* Locate and skip "KEY" */ if (c != 'K' && c != 'k') { EREPORT(("\"KEY\" doesn't appear in file: %s", name)); return NULL; } while ((c = getc(fp)) != EOF) if (isspace(c)) break; while ((c = getc(fp)) != EOF) if (!isspace(c)) break; ungetc(c, fp); /*%< return the charcter to the input field */ /* Handle hex!! FIXME. */ if (fscanf(fp, "%d %d %d", &flags, &proto, &alg) != 3) { EREPORT(("dst_read_public_key(): Can not read flag/proto/alg field from %s\n" ,name)); return (NULL); } /* read in the key string */ fgets(enckey, sizeof(enckey), fp); /* If we aren't at end-of-file, something is wrong. */ while ((c = getc(fp)) != EOF) if (!isspace(c)) break; if (!feof(fp)) { EREPORT(("Key too long in file: %s", name)); return NULL; } fclose(fp); if ((len = strlen(enckey)) <= 0) return (NULL); /* discard \n */ enckey[--len] = '\0'; /* remove leading spaces */ for (notspace = (char *) enckey; isspace((*notspace)&0xff); len--) notspace++; dlen = b64_pton(notspace, deckey, sizeof(deckey)); if (dlen < 0) { EREPORT(("dst_read_public_key: bad return from b64_pton = %d", dlen)); return (NULL); } /* store key and info in a key structure that is returned */ /* return dst_store_public_key(in_name, alg, proto, 666, flags, deckey, dlen);*/ return dst_buffer_to_key(in_name, alg, flags, proto, deckey, dlen); } /*% * dst_write_public_key * Write a key to disk in DNS format. * Parameters * key Pointer to a DST key structure. * Returns * 0 Failure * 1 Success */ static int dst_s_write_public_key(const DST_KEY *key) { FILE *fp; char filename[PATH_MAX]; u_char out_key[RAW_KEY_SIZE]; char enc_key[RAW_KEY_SIZE]; int len = 0; int mode; memset(out_key, 0, sizeof(out_key)); if (key == NULL) { EREPORT(("dst_write_public_key(): No key specified \n")); return (0); } else if ((len = dst_key_to_dnskey(key, out_key, sizeof(out_key)))< 0) return (0); /* Make the filename */ if (dst_s_build_filename(filename, key->dk_key_name, key->dk_id, key->dk_alg, PUBLIC_KEY, PATH_MAX) == -1) { EREPORT(("dst_write_public_key(): Cannot make filename from %s, %d, and %s\n", key->dk_key_name, key->dk_id, PUBLIC_KEY)); return (0); } /* XXX in general this should be a check for symmetric keys */ mode = (key->dk_alg == KEY_HMAC_MD5) ? 0600 : 0644; /* create public key file */ if ((fp = dst_s_fopen(filename, "w+", mode)) == NULL) { EREPORT(("DST_write_public_key: open of file:%s failed (errno=%d)\n", filename, errno)); return (0); } /*write out key first base64 the key data */ if (key->dk_flags & DST_EXTEND_FLAG) b64_ntop(&out_key[6], len - 6, enc_key, sizeof(enc_key)); else b64_ntop(&out_key[4], len - 4, enc_key, sizeof(enc_key)); fprintf(fp, "%s IN KEY %d %d %d %s\n", key->dk_key_name, key->dk_flags, key->dk_proto, key->dk_alg, enc_key); fclose(fp); return (1); } /*% * dst_dnskey_to_public_key * This function converts the contents of a DNS KEY RR into a DST * key structure. * Paramters * len Length of the RDATA of the KEY RR RDATA * rdata A pointer to the the KEY RR RDATA. * in_name Key name to be stored in key structure. * Returns * NULL Failure * NON-NULL Success. Pointer to key structure. * Caller's responsibility to free() it. */ DST_KEY * dst_dnskey_to_key(const char *in_name, const u_char *rdata, const int len) { DST_KEY *key_st; int alg ; int start = DST_KEY_START; if (rdata == NULL || len <= DST_KEY_ALG) /*%< no data */ return (NULL); alg = (u_int8_t) rdata[DST_KEY_ALG]; if (!dst_check_algorithm(alg)) { /*%< make sure alg is available */ EREPORT(("dst_dnskey_to_key(): Algorithm %d not suppored\n", alg)); return (NULL); } if (in_name == NULL) return (NULL); if ((key_st = dst_s_get_key_struct(in_name, alg, 0, 0, 0)) == NULL) return (NULL); key_st->dk_id = dst_s_dns_key_id(rdata, len); key_st->dk_flags = dst_s_get_int16(rdata); key_st->dk_proto = (u_int16_t) rdata[DST_KEY_PROT]; if (key_st->dk_flags & DST_EXTEND_FLAG) { u_int32_t ext_flags; ext_flags = (u_int32_t) dst_s_get_int16(&rdata[DST_EXT_FLAG]); key_st->dk_flags = key_st->dk_flags | (ext_flags << 16); start += 2; } /* * now point to the begining of the data representing the encoding * of the key */ if (key_st->dk_func && key_st->dk_func->from_dns_key) { if (key_st->dk_func->from_dns_key(key_st, &rdata[start], len - start) > 0) return (key_st); } else EREPORT(("dst_dnskey_to_public_key(): unsuppored alg %d\n", alg)); SAFE_FREE(key_st); return (key_st); } /*% * dst_public_key_to_dnskey * Function to encode a public key into DNS KEY wire format * Parameters * key Key structure to encode. * out_storage Location to write the encoded key to. * out_len Size of the output array. * Returns * <0 Failure * >=0 Number of bytes written to out_storage */ int dst_key_to_dnskey(const DST_KEY *key, u_char *out_storage, const int out_len) { u_int16_t val; int loc = 0; int enc_len = 0; if (key == NULL) return (-1); if (!dst_check_algorithm(key->dk_alg)) { /*%< make sure alg is available */ EREPORT(("dst_key_to_dnskey(): Algorithm %d not suppored\n", key->dk_alg)); return (UNSUPPORTED_KEYALG); } memset(out_storage, 0, out_len); val = (u_int16_t)(key->dk_flags & 0xffff); dst_s_put_int16(out_storage, val); loc += 2; out_storage[loc++] = (u_char) key->dk_proto; out_storage[loc++] = (u_char) key->dk_alg; if (key->dk_flags > 0xffff) { /*%< Extended flags */ val = (u_int16_t)((key->dk_flags >> 16) & 0xffff); dst_s_put_int16(&out_storage[loc], val); loc += 2; } if (key->dk_KEY_struct == NULL) return (loc); if (key->dk_func && key->dk_func->to_dns_key) { enc_len = key->dk_func->to_dns_key(key, (u_char *) &out_storage[loc], out_len - loc); if (enc_len > 0) return (enc_len + loc); else return (-1); } else EREPORT(("dst_key_to_dnskey(): Unsupported ALG %d\n", key->dk_alg)); return (-1); } /*% * dst_buffer_to_key * Function to encode a string of raw data into a DST key * Parameters * alg The algorithm (HMAC only) * key A pointer to the data * keylen The length of the data * Returns * NULL an error occurred * NON-NULL the DST key */ DST_KEY * dst_buffer_to_key(const char *key_name, /*!< name of the key */ const int alg, /*!< algorithm */ const int flags, /*!< dns flags */ const int protocol, /*!< dns protocol */ const u_char *key_buf, /*!< key in dns wire fmt */ const int key_len) /*!< size of key */ { DST_KEY *dkey = NULL; int dnslen; u_char dns[2048]; if (!dst_check_algorithm(alg)) { /*%< make sure alg is available */ EREPORT(("dst_buffer_to_key(): Algorithm %d not suppored\n", alg)); return (NULL); } dkey = dst_s_get_key_struct(key_name, alg, flags, protocol, -1); if (dkey == NULL || dkey->dk_func == NULL || dkey->dk_func->from_dns_key == NULL) return (dst_free_key(dkey)); if (dkey->dk_func->from_dns_key(dkey, key_buf, key_len) < 0) { EREPORT(("dst_buffer_to_key(): dst_buffer_to_hmac failed\n")); return (dst_free_key(dkey)); } dnslen = dst_key_to_dnskey(dkey, dns, sizeof(dns)); dkey->dk_id = dst_s_dns_key_id(dns, dnslen); return (dkey); } int dst_key_to_buffer(DST_KEY *key, u_char *out_buff, int buf_len) { int len; /* this function will extrac the secret of HMAC into a buffer */ if (key == NULL) return (0); if (key->dk_func != NULL && key->dk_func->to_dns_key != NULL) { len = key->dk_func->to_dns_key(key, out_buff, buf_len); if (len < 0) return (0); return (len); } return (0); } /*% * dst_s_read_private_key_file * Function reads in private key from a file. * Fills out the KEY structure. * Parameters * name Name of the key to be read. * pk_key Structure that the key is returned in. * in_id Key identifier (tag) * Return * 1 if everthing works * 0 if there is any problem */ static int dst_s_read_private_key_file(char *name, DST_KEY *pk_key, u_int16_t in_id, int in_alg) { int cnt, alg, len, major, minor, file_major, file_minor; int ret, id; char filename[PATH_MAX]; u_char in_buff[RAW_KEY_SIZE], *p; FILE *fp; int dnslen; u_char dns[2048]; if (name == NULL || pk_key == NULL) { EREPORT(("dst_read_private_key_file(): No key name given\n")); return (0); } /* Make the filename */ if (dst_s_build_filename(filename, name, in_id, in_alg, PRIVATE_KEY, PATH_MAX) == -1) { EREPORT(("dst_read_private_key(): Cannot make filename from %s, %d, and %s\n", name, in_id, PRIVATE_KEY)); return (0); } /* first check if we can find the key file */ if ((fp = dst_s_fopen(filename, "r", 0)) == NULL) { EREPORT(("dst_s_read_private_key_file: Could not open file %s in directory %s\n", filename, dst_path[0] ? dst_path : (char *) getcwd(NULL, PATH_MAX - 1))); return (0); } /* now read the header info from the file */ if ((cnt = fread(in_buff, 1, sizeof(in_buff), fp)) < 5) { fclose(fp); EREPORT(("dst_s_read_private_key_file: error reading file %s (empty file)\n", filename)); return (0); } /* decrypt key */ fclose(fp); if (memcmp(in_buff, "Private-key-format: v", 20) != 0) goto fail; len = cnt; p = in_buff; if (!dst_s_verify_str((const char **) (void *)&p, "Private-key-format: v")) { EREPORT(("dst_s_read_private_key_file(): Not a Key file/Decrypt failed %s\n", name)); goto fail; } /* read in file format */ sscanf((char *)p, "%d.%d", &file_major, &file_minor); sscanf(KEY_FILE_FORMAT, "%d.%d", &major, &minor); if (file_major < 1) { EREPORT(("dst_s_read_private_key_file(): Unknown keyfile %d.%d version for %s\n", file_major, file_minor, name)); goto fail; } else if (file_major > major || file_minor > minor) EREPORT(( "dst_s_read_private_key_file(): Keyfile %s version higher than mine %d.%d MAY FAIL\n", name, file_major, file_minor)); while (*p++ != '\n') ; /*%< skip to end of line */ if (!dst_s_verify_str((const char **) (void *)&p, "Algorithm: ")) goto fail; if (sscanf((char *)p, "%d", &alg) != 1) goto fail; while (*p++ != '\n') ; /*%< skip to end of line */ if (pk_key->dk_key_name && !strcmp(pk_key->dk_key_name, name)) SAFE_FREE2(pk_key->dk_key_name, strlen(pk_key->dk_key_name)); pk_key->dk_key_name = (char *) strdup(name); /* allocate and fill in key structure */ if (pk_key->dk_func == NULL || pk_key->dk_func->from_file_fmt == NULL) goto fail; ret = pk_key->dk_func->from_file_fmt(pk_key, (char *)p, &in_buff[len] - p); if (ret < 0) goto fail; dnslen = dst_key_to_dnskey(pk_key, dns, sizeof(dns)); id = dst_s_dns_key_id(dns, dnslen); /* Make sure the actual key tag matches the input tag used in the filename */ if (id != in_id) { EREPORT(("dst_s_read_private_key_file(): actual tag of key read %d != input tag used to build filename %d.\n", id, in_id)); goto fail; } pk_key->dk_id = (u_int16_t) id; pk_key->dk_alg = alg; memset(in_buff, 0, cnt); return (1); fail: memset(in_buff, 0, cnt); return (0); } /*% * Generate and store a public/private keypair. * Keys will be stored in formatted files. * * Parameters & *\par name Name of the new key. Used to create key files *\li K<name>+<alg>+<id>.public and K<name>+<alg>+<id>.private. *\par bits Size of the new key in bits. *\par exp What exponent to use: *\li 0 use exponent 3 *\li non-zero use Fermant4 *\par flags The default value of the DNS Key flags. *\li The DNS Key RR Flag field is defined in RFC2065, * section 3.3. The field has 16 bits. *\par protocol *\li Default value of the DNS Key protocol field. *\li The DNS Key protocol field is defined in RFC2065, * section 3.4. The field has 8 bits. *\par alg What algorithm to use. Currently defined: *\li KEY_RSA 1 *\li KEY_DSA 3 *\li KEY_HMAC 157 *\par out_id The key tag is returned. * * Return *\li NULL Failure *\li non-NULL the generated key pair * Caller frees the result, and its dk_name pointer. */ DST_KEY * dst_generate_key(const char *name, const int bits, const int exp, const int flags, const int protocol, const int alg) { DST_KEY *new_key = NULL; int dnslen; u_char dns[2048]; if (name == NULL) return (NULL); if (!dst_check_algorithm(alg)) { /*%< make sure alg is available */ EREPORT(("dst_generate_key(): Algorithm %d not suppored\n", alg)); return (NULL); } new_key = dst_s_get_key_struct(name, alg, flags, protocol, bits); if (new_key == NULL) return (NULL); if (bits == 0) /*%< null key we are done */ return (new_key); if (new_key->dk_func == NULL || new_key->dk_func->generate == NULL) { EREPORT(("dst_generate_key_pair():Unsupported algorithm %d\n", alg)); return (dst_free_key(new_key)); } if (new_key->dk_func->generate(new_key, exp) <= 0) { EREPORT(("dst_generate_key_pair(): Key generation failure %s %d %d %d\n", new_key->dk_key_name, new_key->dk_alg, new_key->dk_key_size, exp)); return (dst_free_key(new_key)); } dnslen = dst_key_to_dnskey(new_key, dns, sizeof(dns)); if (dnslen != UNSUPPORTED_KEYALG) new_key->dk_id = dst_s_dns_key_id(dns, dnslen); else new_key->dk_id = 0; return (new_key); } /*% * Release all data structures pointed to by a key structure. * * Parameters *\li f_key Key structure to be freed. */ DST_KEY * dst_free_key(DST_KEY *f_key) { if (f_key == NULL) return (f_key); if (f_key->dk_func && f_key->dk_func->destroy) f_key->dk_KEY_struct = f_key->dk_func->destroy(f_key->dk_KEY_struct); else { EREPORT(("dst_free_key(): Unknown key alg %d\n", f_key->dk_alg)); } if (f_key->dk_KEY_struct) { free(f_key->dk_KEY_struct); f_key->dk_KEY_struct = NULL; } if (f_key->dk_key_name) SAFE_FREE(f_key->dk_key_name); SAFE_FREE(f_key); return (NULL); } /*% * Return the maximim size of signature from the key specified in bytes * * Parameters *\li key * * Returns * \li bytes */ int dst_sig_size(DST_KEY *key) { switch (key->dk_alg) { case KEY_HMAC_MD5: return (16); case KEY_HMAC_SHA1: return (20); case KEY_RSA: return (key->dk_key_size + 7) / 8; case KEY_DSA: return (40); default: EREPORT(("dst_sig_size(): Unknown key alg %d\n", key->dk_alg)); return -1; } } /*! \file */

↑ V597 The compiler could delete the 'memset' function call, which is used to flush 'in_buff' buffer. The memset_s() function should be used to erase the private data.

↑ V597 The compiler could delete the 'memset' function call, which is used to flush 'key_st' object. The memset_s() function should be used to erase the private data.

↑ V597 The compiler could delete the 'memset' function call, which is used to flush 'encoded_block' buffer. The memset_s() function should be used to erase the private data.

↑ V597 The compiler could delete the 'memset' function call, which is used to flush 'f_key' object. The memset_s() function should be used to erase the private data.